Search results for: tissue imaging
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2689

Search results for: tissue imaging

289 Acoustic Radiation Pressure Detaches Myoblast from Culture Substrate by Assistance of Serum-Free Medium

Authors: Yuta Kurashina, Chikahiro Imashiro, Kiyoshi Ohnuma, Kenjiro Takemura

Abstract:

Research objectives and goals: To realize clinical applications of regenerative medicine, a mass cell culture is highly required. In a conventional cell culture, trypsinization was employed for cell detachment. However, trypsinization causes proliferation decrease due to injury of cell membrane. In order to detach cells using an enzyme-free method, therefore, this study proposes a novel cell detachment method capable of detaching adherent cells using acoustic radiation pressure exposed to the dish by the assistance of serum-free medium with ITS liquid medium supplement. Methods used In order to generate acoustic radiation pressure, a piezoelectric ceramic plate was glued on a glass plate to configure an ultrasonic transducer. The glass plate and a chamber wall compose a chamber in which a culture dish is placed in glycerol. Glycerol transmits acoustic radiation pressure to adhered cells on the culture dish. To excite a resonance vibration of transducer, AC signal with 29-31 kHz (swept) and 150, 300, and 450 V was input to the transducer for 5 min. As a pretreatment to reduce cell adhesivity, serum-free medium with ITS liquid medium supplement was spread to the culture dish before exposed to acoustic radiation pressure. To evaluate the proposed cell detachment method, C2C12 myoblast cells (8.0 × 104 cells) were cultured on a ø35 culture dish for 48 hr, and then the medium was replaced with the serum-free medium with ITS liquid medium supplement for 24 hr. We replaced the medium with phosphate buffered saline and incubated cells for 10 min. After that, cells were exposed to the acoustic radiation pressure for 5 min. We also collected cells by using trypsinization as control. Cells collected by the proposed method and trypsinization were respectively reseeded in ø60 culture dishes and cultured for 24 hr. Then, the number of proliferated cells was counted. Results achieved: By a phase contrast microscope imaging, shrink of lamellipodia was observed before exposed to acoustic radiation pressure, and no cells remained on the culture dish after the exposed of acoustic radiation pressure. This result suggests that serum-free medium with ITS liquid inhibits adhesivity of cells and acoustic radiation pressure detaches cells from the dish. Moreover, the number of proliferated cells 24 hr after collected by the proposed method with 150 and 300 V is the same or more than that by trypsinization, i.e., cells were proliferated 15% higher with the proposed method using acoustic radiation pressure than with the traditional cell collecting method of trypsinization. These results proved that cells were able to be collected by using the appropriate exposure of acoustic radiation pressure. Conclusions: This study proposed a cell detachment method using acoustic radiation pressure by the assistance of serum-free medium. The proposed method provides an enzyme-free cell detachment method so that it may be used in future clinical applications instead of trypsinization.

Keywords: acoustic radiation pressure, cell detachment, enzyme free, ultrasonic transducer

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288 Geochemical Characterization for Identification of Hydrocarbon Generation: Implication of Unconventional Gas Resources

Authors: Yousif M. Makeen

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This research will address the processes of geochemical characterization and hydrocarbon generation process occurring within hydrocarbon source and/or reservoir rocks. The geochemical characterization includes organic-inorganic associations that influence the storage capacity of unconventional hydrocarbon resources (e.g. shale gas) and the migration process of oil/gas of the petroleum source/reservoir rocks. Kerogen i.e. the precursor of petroleum, occurs in various forms and types, may either be oil-prone, gas-prone, or both. China has a number of petroleum-bearing sedimentary basins commonly associated with shale gas, oil sands, and oil shale. Taken Sichuan basin as a selected basin in this study, the Sichuan basin has recorded notable successful discoveries of shale gas especially in the marine shale reservoirs within the area. However, a notable discoveries of lacustrine shale in the North-Este Fuling area indicate the accumulation of shale gas within non-marine source rock. The objective of this study is to evaluate the hydrocarbon storage capacity, generation, and retention processes in the rock matrix of hydrocarbon source/reservoir rocks within the Sichuan basin using an advanced X-ray tomography 3D imaging computational technology, commonly referred to as Micro-CT, SEM (Scanning Electron Microscope), optical microscope as well as organic geochemical facilities (e.g. vitrinite reflectance and UV light). The preliminary results of this study show that the lacustrine shales under investigation are acting as both source and reservoir rocks, which are characterized by very fine grains and very low permeability and porosity. Three pore structures have also been characterized in the study in the lacustrine shales, including organic matter pores, interparticle pores and intraparticle pores using x-ray Computed Tomography (CT). The benefits of this study would be a more successful oil and gas exploration and higher recovery factor, thus having a direct economic impact on China and the surrounding region. Methodologies: SRA TOC/TPH or Rock-Eval technique will be used to determine the source rock richness (S1 and S2) and Tmax. TOC analysis will be carried out using a multi N/C 3100 analyzer. The SRA and TOC results were used in calculating other parameters such as hydrogen index (HI) and production index (PI). This analysis will indicate the quantity of the organic matter. Minimum TOC limits generally accepted as essential for a source-rock are 0.5% for shales and 0.2% for carbonates. Contributions: This research could solve issues related to oil potential, provide targets, and serve as a pathfinder to future exploration activity in the Sichuan basin.

Keywords: shale gas, unconventional resources, organic chemistry, Sichuan basin

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287 Fuzzy Optimization for Identifying Anticancer Targets in Genome-Scale Metabolic Models of Colon Cancer

Authors: Feng-Sheng Wang, Chao-Ting Cheng

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Developing a drug from conception to launch is costly and time-consuming. Computer-aided methods can reduce research costs and accelerate the development process during the early drug discovery and development stages. This study developed a fuzzy multi-objective hierarchical optimization framework for identifying potential anticancer targets in a metabolic model. First, RNA-seq expression data of colorectal cancer samples and their healthy counterparts were used to reconstruct tissue-specific genome-scale metabolic models. The aim of the optimization framework was to identify anticancer targets that lead to cancer cell death and evaluate metabolic flux perturbations in normal cells that have been caused by cancer treatment. Four objectives were established in the optimization framework to evaluate the mortality of cancer cells for treatment and to minimize side effects causing toxicity-induced tumorigenesis on normal cells and smaller metabolic perturbations. Through fuzzy set theory, a multiobjective optimization problem was converted into a trilevel maximizing decision-making (MDM) problem. The applied nested hybrid differential evolution was applied to solve the trilevel MDM problem using two nutrient media to identify anticancer targets in the genome-scale metabolic model of colorectal cancer, respectively. Using Dulbecco’s Modified Eagle Medium (DMEM), the computational results reveal that the identified anticancer targets were mostly involved in cholesterol biosynthesis, pyrimidine and purine metabolisms, glycerophospholipid biosynthetic pathway and sphingolipid pathway. However, using Ham’s medium, the genes involved in cholesterol biosynthesis were unidentifiable. A comparison of the uptake reactions for the DMEM and Ham’s medium revealed that no cholesterol uptake reaction was included in DMEM. Two additional media, i.e., a cholesterol uptake reaction was included in DMEM and excluded in HAM, were respectively used to investigate the relationship of tumor cell growth with nutrient components and anticancer target genes. The genes involved in the cholesterol biosynthesis were also revealed to be determinable if a cholesterol uptake reaction was not induced when the cells were in the culture medium. However, the genes involved in cholesterol biosynthesis became unidentifiable if such a reaction was induced.

Keywords: Cancer metabolism, genome-scale metabolic model, constraint-based model, multilevel optimization, fuzzy optimization, hybrid differential evolution

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286 Anti -proliferative and Apoptotic Effects of Selected Saudi Herbs from the Rhamnaceae, Polygonaceae, and Apocynaceae Families Against Various Cancer Cell Lines

Authors: Allulu Yousef Alturki, Raghad Abdullah Alshafi, Sara Abdulaziz Alghashem, Sahar Saleh Alghamdi, Rasha Saad Suliman, Zeyad Alehaideb, Rizwan Ali

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Cancer is recognized as a worldwide public health concern. Therefore, there is a continuous quest to discover new effective medications with less side-effects. In recent years, researchers have shown an increased interest in medicinal plants as several plant species have shown promising biological activities. Thus, we seek to investigate three medicinal herbs that are commonly-found in the Middle Easternregion and yet have not been explored in depth, including plants belonging to the Rhamnaceae, Polygonaceae, and Apocynaceaeplant families. Initially, we investigated using three types of cancer cell lines for breast, colorectal, and liver cancers. We performed high Content Imaging (HCI)-Apoptosis Assay and ApoTox-Glo™ Triplex Assay on KAIMRC2 and HCT8 cell lines. The highest activity of HCI-Apoptosis Assay was with Calligonumcomosum and Ziziphusnummularia in ethanol, followed by Calotropis procera and Ziziphusnummularia in ethyl acetate. The IC50values for the families of Rhamnaceae, Polygonaceae, and Apocynaceae in HepG2 and HCT8 cell lines ranged from 0.089 to 9.84mg/mL and 0.080to 15.08mg/mL, respectively. Further screening was conducted on an additional two cell lines, namely the MDA-MB-231 and KAIMRC2, for selected seven extracts with the highest activity having IC50values ranged from 0.058 to0.51mg/mL and 0.029 to0.19mg/mL, respectively. Continuous scientific investigations to isolate and characterize the potent bioactive phytochemical(s) are warranted. Funding: The authors acknowledge financial support from King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard Health Affairs, Riyadh, Kingdom of Saudi Arabia. Institutional Review Board Statement: The study was approved by the Institutional Review Board of the Institutional Review Board of King Abdullah International Medical Research Center (SP21R/463/12, 24 January 2022). Acknowledgments: The authors want to express their gratitude to the College of Pharmacy (COP) at King Saud bin Abdulaziz University for Health Sciences (KSAU-HS) and King Abdullah International Medical Research Center (KAIMRC) for their continued support.

Keywords: rhamnaceae, polygonaceae, apocynaceae, natural products

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285 Media Facades Utilization for Sustainable Tourism Promotion in Historic Places: Case Study of the Walled City of Famagusta, North Cyprus

Authors: Nikou Javadi, Uğur Dağlı

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The importance of culture and tourism in the attractiveness and competitiveness of the countries is central, and many regions are evidencing their cultural assets, tangible and intangible, as a means to create comparative advantages in tourism and produce a distinctive place in response to the pressures of globalization. Culture and tourism are interlinked because of their obvious combination and growth potential. Cultural tourism is a crucial global tourism market with fast growing. Regions can develop significant relations between culture and tourism to increase their attractiveness as places to visit, live and invest, increasing their competitiveness. Accordingly, having new and creative approach to historical areas as cultural value-based destinations can improve their conditions to promote tourism. Furthermore, in 21st century, media become the most important factor affecting the development of urban cities, including public places. As a result of the digital revolution, re-imaging and re-linkage public places by media are essential to create more interactions between public spaces and users, interaction media display, and urban screens, one of the most important defined media. This interaction can transform the urban space from being neglected to be more interactive space with users, especially the pedestrians. The paper focuses on The Walled City of Famagusta. As many other historic quarters elsewhere in the world, is in a process, of decay and deterioration, and its functionally distinctive areas are severely threatened by physical, functional, locational, and image obsolescence at varying degrees. So the focus on the future development of this area through tourism promotion can be an appropriate decision for the monument enhancement of the spatial quality in Walled City of Famagusta. In this paper, it is aimed to identify the effects of these new digital factors to transform public spaces especially in historic urban areas to promote creative tourism. Accordingly, two different analysis methods are used as well as a theoretical review. The first is case study on site and the second is Close ended questionnaire, test many concepts raised in this paper. The physical analysis on site carried out in order to evaluate the walled city restoration for touristic purpose. Besides, theoretical review is done in order to provide background to the subject and cleared Factors to attract tourists.

Keywords: historical areas, media façade, sustainable tourism, Walled city of Famagusta

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284 Effect of Self-Lubricating Carbon Materials on the Tribological Performance of Ultra-High Molecular Weight Polyethylene

Authors: Nayeli Camacho, Fernanda Lara-Perez, Carolina Ortega-Portilla, Diego G. Espinosa-Arbelaez, Juan M. Alvarado-Orozco, Guillermo C. Mondragon-Rodriguez

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Ultra-high molecular weight polyethylene (UHMWPE) has been the gold standard material for total knee replacements for almost five decades. Wear damage to UHMWPE articulating surface is inevitable due to the natural sliding and rolling movements of the knee. This generates a considerable amount of wear debris, which results in mechanical instability of the joint, reduces joint mobility, increases pain with detrimental biologic responses, and causes component loosening. The presence of wear particles has been closely related to adverse reactions in the knee joint surrounding tissue, especially for particles in the range of 0.3 to 2 μm. Carbon-based materials possess excellent mechanical properties and have shown great promise in tribological applications. In this study, diamond-like carbon coatings (DLC) and carbon nanotubes (CNTs) were used to decrease the wear rate of ultra-high molecular weight polyethylene. A titanium doped DLC (Ti-DLC) was deposited by magnetron sputtering on stainless steel precision spheres while CNTs were used as a second phase reinforcement in UHMWPE at a concentration of 1.25 wt.%. A comparative tribological analysis of the wear of UHMWPE and UHMWPE-CNTs with a stainless steel counterpart with and without Ti-DLC coating is presented. The experimental wear testing was performed on a pin-on-disc tribometer under dry conditions, using a reciprocating movement with a load of 1 N at a frequency of 2 Hz for 100,000 and 200,000 cycles. The wear tracks were analyzed with high-resolution scanning electron microscopy to determine wear modes and observe the size and shape of the wear debris. Furthermore, profilometry was used to study the depth of the wear tracks and to map the wear of the articulating surface. The wear tracks at 100,000 and 200,000 cycles on all samples were relatively shallow, and they were in the range of average roughness. It was observed that the Ti-DLC coating decreases the mass loss in the UHMWPE and the depth of the wear track. The combination of both carbon-based materials decreased the material loss compared to the system of stainless steel and UHMWPE. Burnishing of the surface was the predominant wear mode observed with all the systems, more subtle for the systems with Ti-DLC coatings. Meanwhile, in the system composed of stainless steel-UHMWPE, the intrinsic surface roughness of the material was completely replaced by the wear tracks.

Keywords: CNT reinforcement, self-lubricating materials, Ti-DLC, UHMWPE tribological performance

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283 Gluten Intolerance, Celiac Disease, and Neuropsychiatric Disorders: A Translational Perspective

Authors: Jessica A. Hellings, Piyushkumar Jani

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Background: Systemic autoimmune disorders are increasingly implicated in neuropsychiatric illness, especially in the setting of treatment resistance in individuals of all ages. Gluten allergy in fullest extent results in celiac disease, affecting multiple organs including central nervous system (CNS). Clinicians often lack awareness of the association between neuropsychiatric illness and gluten allergy, partly since many such research studies are published in immunology and gastroenterology journals. Methods: Following a Pubmed literature search and online searches on celiac disease websites, 40 articles are critically reviewed in detail. This work reviews celiac disease, gluten intolerance and current evidence of their relationship to neuropsychiatric and systemic illnesses. The review also covers current work-up and diagnosis, as well as dietary interventions, gluten restriction outcomes, and future research directions. Results: Gluten allergy in susceptible individuals damages the small intestine, producing a leaky gut and malabsorption state, as well as allowing antibodies into the bloodstream, which attack major organs. Lack of amino acid precursors for neurotransmitter synthesis together with antibody-associated brain changes and hypoperfusion may result in neuropsychiatric illness. This is well documented; however, studies in neuropsychiatry are often small. In the large CATIE trial, subjects with schizophrenia had significantly increased antibodies to tissue transglutaminase (TTG), and antigliadin antibodies, both significantly greater gluten antibodies than in control subjects. On later follow up, TTG-6 antibodies were identified in these subjects’ brains but not in their intestines. Significant evidence mostly from small studies also exists for gluten allergy and celiac-related depression, anxiety disorders, attention-deficit/hyperactivity disorder, autism spectrum disorders, ataxia, and epilepsy. Dietary restriction of gluten resulted in remission in several published cases, including for treatment-resistant schizophrenia. Conclusions: Ongoing and larger studies are needed of the diagnosis and treatment efficacy of the gluten-free diet in neuropsychiatric illness. Clinicians should ask about the patient history of anemia, hypothyroidism, irritable bowel syndrome and family history of benefit from the gluten-free diet, not limited to but especially in cases of treatment resistance. Obtaining gluten antibodies by a simple blood test, and referral for gastrointestinal work-up in positive cases should be considered.

Keywords: celiac, gluten, neuropsychiatric, translational

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282 Protective Effect of Ginger Root Extract on Dioxin-Induced Testicular Damage in Rats

Authors: Hamid Abdulroof Saleh

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Background: Dioxins are one of the most widely distributed environmental pollutants. Dioxins consist of feedstock during the preparation of some industries, such as the paper industry as they can be produced in the atmosphere during the process of burning garbage and waste, especially medical waste. Dioxins can be found in the adipose tissues of animals in the food chain as well as in human breast milk. 2,3,7,8-Tetrachlorodibenzo-pdioxin (TCDD) is the most toxic component of a large group of dioxins. Humans are exposed to TCDD through contaminated food items like meat, fish, milk products, eggs etc. Recently, natural formulations relating to reducing or eliminating TCDD toxicity have been in focus. Ginger rhizome (Zingiber officinale R., family: Zingiberaceae), is used worldwide as a spice. Both antioxidative and androgenic activity of Z. officinale was reported in animal models. Researchers showed that ginger oil has dominative protective effect on DNA damage and might act as a scavenger of oxygen radical and might be used as an antioxidant. Aim of the work: The present study was undertaken to evaluate the toxic effect of TCDD on the structure and histoarchitecture of the testis and the protective role of co-administration of ginger root extract to prevent this toxicity. Materials & Methods: Male adult rats of Sprague-Dawley strain were assigned to four groups, eight rats in each; control group, dioxin treated group (given TCDD at the dose of 100 ng/kg Bwt/day by gavage), ginger treated group (given 50 mg/kg Bwt/day of ginger root extract by gavage), dioxin and ginger treated group (given TCDD at the dose of 100 ng/kg Bwt/day and 50 mg/kg Bwt/day of ginger root extract by gavages). After three weeks, rats were weighed and sacrificed where testis were removed and weighted. The testes were processed for routine paraffin embedding and staining. Tissue sections were examined for different morphometric and histopathological changes. Results: Dioxin administration showed a harmful effects in the body, testis weight and other morphometric parameters of the testis. In addition, it produced varying degrees of damage to the seminiferous tubules, which were shrunken and devoid of mature spermatids. The basement membrane was disorganized with vacuolization and loss of germinal cells. The co-administration of ginger root extract showed obvious improvement in the above changes and showed reversible morphometric and histopathological changes of the seminiferous tubules. Conclusion: Ginger root extract treatment in this study was successful in reversing all morphometric and histological changes of dioxin testicular damage. Therefore, it showed a protective effect on testis against dioxin toxicity.

Keywords: dioxin, ginger, rat, testis

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281 Effect of 8-OH-DPAT on the Behavioral Indicators of Stress and on the Number of Astrocytes after Exposure to Chronic Stress

Authors: Ivette Gonzalez-Rivera, Diana B. Paz-Trejo, Oscar Galicia-Castillo, David N. Velazquez-Martinez, Hugo Sanchez-Castillo

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Prolonged exposure to stress can cause disorders related with dysfunction in the prefrontal cortex such as generalized anxiety and depression. These disorders involve alterations in neurotransmitter systems; the serotonergic system—a target of the drugs that are commonly used as a treatment to these disorders—is one of them. Recent studies suggest that 5-HT1A receptors play a pivotal role in the serotonergic system regulation and in stress responses. In the same way, there is increasing evidence that astrocytes are involved in the pathophysiology of stress. The aim of this study was to examine the effects of 8-OH-DPAT, a selective agonist of 5-HT1A receptors, in the behavioral signs of anxiety and anhedonia as well as in the number of astrocytes in the medial prefrontal cortex (mPFC) after exposure to chronic stress. They used 50 male Wistar rats of 250-350 grams housed in standard laboratory conditions and treated in accordance with the ethical standards of use and care of laboratory animals. A protocol of chronic unpredictable stress was used for 10 consecutive days during which the presentation of stressors such as motion restriction, water deprivation, wet bed, among others, were used. 40 rats were subjected to the stress protocol and then were divided into 4 groups of 10 rats each, which were administered 8-OH-DPAT (Tocris, USA) intraperitoneally with saline as vehicle in doses 0.0, 0.3, 1.0 and 2.0 mg/kg respectively. Another 10 rats were not subjected to the stress protocol or the drug. Subsequently, all the rats were measured in an open field test, a forced swimming test, sucrose consume, and a cero maze test. At the end of this procedure, the animals were sacrificed, the brain was removed and the tissue of the mPFC (Bregma: 4.20, 3.70, 2.70, 2.20) was processed in immunofluorescence staining for astrocytes (Anti-GFAP antibody - astrocyte maker, ABCAM). Statistically significant differences were found in the behavioral tests of all groups, showing that the stress group with saline administration had more indicators of anxiety and anhedonia than the control group and the groups with administration of 8-OH-DPAT. Also, a dose dependent effect of 8-OH-DPAT was found on the number of astrocytes in the mPFC. The results show that 8-OH-DPAT can modulate the effect of stress in both behavioral and anatomical level. Also they indicate that 5-HT1A receptors and astrocytes play an important role in the stress response and may modulate the therapeutic effect of serotonergic drugs, so they should be explored as a fundamental part in the treatment of symptoms of stress and in the understanding of the mechanisms of stress responses.

Keywords: anxiety, prefrontal cortex, serotonergic system, stress

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280 Nanofluidic Cell for Resolution Improvement of Liquid Transmission Electron Microscopy

Authors: Deybith Venegas-Rojas, Sercan Keskin, Svenja Riekeberg, Sana Azim, Stephanie Manz, R. J. Dwayne Miller, Hoc Khiem Trieu

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Liquid Transmission Electron Microscopy (TEM) is a growing area with a broad range of applications from physics and chemistry to material engineering and biology, in which it is possible to image in-situ unseen phenomena. For this, a nanofluidic device is used to insert the nanoflow with the sample inside the microscope in order to keep the liquid encapsulated because of the high vacuum. In the last years, Si3N4 windows have been widely used because of its mechanical stability and low imaging contrast. Nevertheless, the pressure difference between the inside fluid and the outside vacuum in the TEM generates bulging in the windows. This increases the imaged fluid volume, which decreases the signal to noise ratio (SNR), limiting the achievable spatial resolution. With the proposed device, the membrane is fortified with a microstructure capable of stand higher pressure differences, and almost removing completely the bulging. A theoretical study is presented with Finite Element Method (FEM) simulations which provide a deep understanding of the membrane mechanical conditions and proves the effectiveness of this novel concept. Bulging and von Mises Stress were studied for different membrane dimensions, geometries, materials, and thicknesses. The microfabrication of the device was made with a thin wafer coated with thin layers of SiO2 and Si3N4. After the lithography process, these layers were etched (reactive ion etching and buffered oxide etch (BOE) respectively). After that, the microstructure was etched (deep reactive ion etching). Then the back side SiO2 was etched (BOE) and the array of free-standing micro-windows was obtained. Additionally, a Pyrex wafer was patterned with windows, and inlets/outlets, and bonded (anodic bonding) to the Si side to facilitate the thin wafer handling. Later, a thin spacer is sputtered and patterned with microchannels and trenches to guide the nanoflow with the samples. This approach reduces considerably the common bulging problem of the window, improving the SNR, contrast and spatial resolution, increasing substantially the mechanical stability of the windows, allowing a larger viewing area. These developments lead to a wider range of applications of liquid TEM, expanding the spectrum of possible experiments in the field.

Keywords: liquid cell, liquid transmission electron microscopy, nanofluidics, nanofluidic cell, thin films

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279 Assessment of the Efficacy of Routine Medical Tests in Screening Medical Radiation Staff in Shiraz University of Medical Sciences Educational Centers

Authors: Z. Razi, S. M. J. Mortazavi, N. Shokrpour, Z. Shayan, F. Amiri

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Long-term exposure to low doses of ionizing radiation occurs in radiation health care workplaces. Although doses in health professions are generally very low, there are still matters of concern. The radiation safety program promotes occupational radiation safety through accurate and reliable monitoring of radiation workers in order to effectively manage radiation protection. To achieve this goal, it has become mandatory to implement health examination periodically. As a result, based on the hematological alterations, working populations with a common occupational radiation history are screened. This paper calls into question the effectiveness of blood component analysis as a screening program which is mandatory for medical radiation workers in some countries. This study details the distribution and trends of changes in blood components, including white blood cells (WBCs), red blood cells (RBCs) and platelets as well as received cumulative doses from occupational radiation exposure. This study was conducted among 199 participants and 100 control subjects at the medical imaging departments at the central hospital of Shiraz University of Medical Sciences during the years 2006–2010. Descriptive and analytical statistics, considering the P-value<0.05 as statistically significance was used for data analysis. The results of this study show that there is no significant difference between the radiation workers and controls regarding WBCs and platelet count during 4 years. Also, we have found no statistically significant difference between the two groups with respect to RBCs. Besides, no statistically significant difference was observed with respect to RBCs with regards to gender, which has been analyzed separately because of the lower reference range for normal RBCs levels in women compared to men and. Moreover, the findings confirm that in a separate evaluation between WBCs count and the personnel’s working experience and their annual exposure dose, results showed no linear correlation between the three variables. Since the hematological findings were within the range of control levels, it can be concluded that the radiation dosage (which was not more than 7.58 mSv in this study) had been too small to stimulate any quantifiable change in medical radiation worker’s blood count. Thus, use of more accurate method for screening program based on the working profile of the radiation workers and their accumulated dose is suggested. In addition, complexity of radiation-induced functions and the influence of various factors on blood count alteration should be taken into account.

Keywords: blood cell count, mandatory testing, occupational exposure, radiation

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278 Fibrin Glue Reinforcement of Choledochotomy Closure Suture Line for Prevention of Bile Leak in Patients Undergoing Laparoscopic Common Bile Duct Exploration with Primary Closure: A Pilot Study

Authors: Rahul Jain, Jagdish Chander, Anish Gupta

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Introduction: Laparoscopic common bile duct exploration (LCBDE) allows cholecystectomy and the removal of common bile duct (CBD) stones to be performed during the same sitting, thereby decreasing hospital stay. CBD exploration through choledochotomy can be closed primarily with an absorbable suture material, but can lead to biliary leakage postoperatively. In this study we tried to find a solution to further lower the incidence of bile leakage by using fibrin glue to reinforce the sutures put on choledochotomy suture line. It has haemostatic and sealing action, through strengthening the last step of the physiological coagulation and biostimulation, which favours the formation of new tissue matrix. Methodology: This study was conducted at a tertiary care teaching hospital in New Delhi, India, from 2011 to 2013. 20 patients with CBD stones documented on MRCP with CBD diameter of 9 mm or more were included in this study. Patients were randomized into two groups namely Group A in which choledochotomy was closed with polyglactin 4-0 suture and suture line reinforced with fibrin glue, and Group ‘B’ in which choledochotomy was closed with polyglactin 4-0 suture alone. Both the groups were evaluated and compared on clinical parameters such as operative time, drain content, drain output, no. of days drain was required, blood loss & transfusion requirements, length of postoperative hospital stay and conversion to open surgery. Results: The operative time for Group A ranged from 60 to 210 min (mean 131.50 min) and Group B 65 to 300 min (mean 140 minutes). The blood loss in group A ranged from 10 to 120 ml (mean 51.50 ml), in group B it ranged from 10 to 200 ml (mean 53.50 ml). In Group A, there was no case of bile leak but there was bile leak in 2 cases in Group B, minimum 0 and maximum 900 ml with a mean of 97 ml and p value of 0.147 with no statistically significant difference in bile leak in test and control groups. The minimum and maximum serous drainage in Group A was nil & 80 ml (mean 11 ml) and in Group B was nil & 270 ml (mean 72.50 ml). The p value came as 0.028 which is statistically significant. Thus serous leakage in Group A was significantly less than in Group B. The drains in Group A were removed from 2 to 4 days (mean: 3 days) while in Group B from 2 to 9 days (mean: 3.9 days). The patients in Group A stayed in hospital post operatively from 3 to 8 days (mean: 5.30) while in Group B it ranged from 3 to 10 days with a mean of 5 days. Conclusion: Fibrin glue application on CBD decreases bile leakage but in statistically insignificant manner. Fibrin glue application on CBD can significantly decrease post operative serous drainage after LCBDE. Fibrin glue application on CBD is safe and easy technique without any significant adverse effects and can help less experienced surgeons performing LCBDE.

Keywords: bile leak, fibrin glue, LCBDE, serous leak

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277 Structural and Biochemical Characterization of Red and Green Emitting Luciferase Enzymes

Authors: Wael M. Rabeh, Cesar Carrasco-Lopez, Juliana C. Ferreira, Pance Naumov

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Bioluminescence, the emission of light from a biological process, is found in various living organisms including bacteria, fireflies, beetles, fungus and different marine organisms. Luciferase is an enzyme that catalyzes a two steps oxidation of luciferin in the presence of Mg2+ and ATP to produce oxyluciferin and releases energy in the form of light. The luciferase assay is used in biological research and clinical applications for in vivo imaging, cell proliferation, and protein folding and secretion analysis. The luciferase enzyme consists of two domains, a large N-terminal domain (1-436 residues) that is connected to a small C-terminal domain (440-544) by a flexible loop that functions as a hinge for opening and closing the active site. The two domains are separated by a large cleft housing the active site that closes after binding the substrates, luciferin and ATP. Even though all insect luciferases catalyze the same chemical reaction and share 50% to 90% sequence homology and high structural similarity, they emit light of different colors from green at 560nm to red at 640 nm. Currently, the majority of the structural and biochemical studies have been conducted on green-emitting firefly luciferases. To address the color emission mechanism, we expressed and purified two luciferase enzymes with blue-shifted green and red emission from indigenous Brazilian species Amydetes fanestratus and Phrixothrix, respectively. The two enzymes naturally emit light of different colors and they are an excellent system to study the color-emission mechanism of luciferases, as the current proposed mechanisms are based on mutagenesis studies. Using a vapor-diffusion method and a high-throughput approach, we crystallized and solved the crystal structure of both enzymes, at 1.7 Å and 3.1 Å resolution respectively, using X-ray crystallography. The free enzyme adopted two open conformations in the crystallographic unit cell that are different from the previously characterized firefly luciferase. The blue-shifted green luciferase crystalized as a monomer similar to other luciferases reported in literature, while the red luciferases crystalized as an octamer and was also purified as an octomer in solution. The octomer conformation is the first of its kind for any insect’s luciferase, which might be relate to the red color emission. Structurally designed mutations confirmed the importance of the transition between the open and close conformations in the fine-tuning of the color and the characterization of other interesting mutants is underway.

Keywords: bioluminescence, enzymology, structural biology, x-ray crystallography

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276 Magnetic Navigation of Nanoparticles inside a 3D Carotid Model

Authors: E. G. Karvelas, C. Liosis, A. Theodorakakos, T. E. Karakasidis

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Magnetic navigation of the drug inside the human vessels is a very important concept since the drug is delivered to the desired area. Consequently, the quantity of the drug required to reach therapeutic levels is being reduced while the drug concentration at targeted sites is increased. Magnetic navigation of drug agents can be achieved with the use of magnetic nanoparticles where anti-tumor agents are loaded on the surface of the nanoparticles. The magnetic field that is required to navigate the particles inside the human arteries is produced by a magnetic resonance imaging (MRI) device. The main factors which influence the efficiency of the usage of magnetic nanoparticles for biomedical applications in magnetic driving are the size and the magnetization of the biocompatible nanoparticles. In this study, a computational platform for the simulation of the optimal gradient magnetic fields for the navigation of magnetic nanoparticles inside a carotid artery is presented. For the propulsion model of the particles, seven major forces are considered, i.e., the magnetic force from MRIs main magnet static field as well as the magnetic field gradient force from the special propulsion gradient coils. The static field is responsible for the aggregation of nanoparticles, while the magnetic gradient contributes to the navigation of the agglomerates that are formed. Moreover, the contact forces among the aggregated nanoparticles and the wall and the Stokes drag force for each particle are considered, while only spherical particles are used in this study. In addition, gravitational forces due to gravity and the force due to buoyancy are included. Finally, Van der Walls force and Brownian motion are taken into account in the simulation. The OpenFoam platform is used for the calculation of the flow field and the uncoupled equations of particles' motion. To verify the optimal gradient magnetic fields, a covariance matrix adaptation evolution strategy (CMAES) is used in order to navigate the particles into the desired area. A desired trajectory is inserted into the computational geometry, which the particles are going to be navigated in. Initially, the CMAES optimization strategy provides the OpenFOAM program with random values of the gradient magnetic field. At the end of each simulation, the computational platform evaluates the distance between the particles and the desired trajectory. The present model can simulate the motion of particles when they are navigated by the magnetic field that is produced by the MRI device. Under the influence of fluid flow, the model investigates the effect of different gradient magnetic fields in order to minimize the distance of particles from the desired trajectory. In addition, the platform can navigate the particles into the desired trajectory with an efficiency between 80-90%. On the other hand, a small number of particles are stuck to the walls and remains there for the rest of the simulation.

Keywords: artery, drug, nanoparticles, navigation

Procedia PDF Downloads 103
275 Advances in Genome Editing and Future Prospects for Sorghum Improvement: A Review

Authors: Micheale Yifter Weldemichael, Hailay Mehari Gebremedhn, Teklehaimanot Hailesslasie Teklu

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Recent developments in targeted genome editing accelerated genetic research and opened new potentials to improve crops for better yields and quality. Given the significance of cereal crops as a primary source of food for the global population, the utilization of contemporary genome editing techniques like CRISPR/Cas9 is timely and crucial. CRISPR/Cas technology has enabled targeted genomic modifications, revolutionizing genetic research and exploration. Application of gene editing through CRISPR/Cas9 in enhancing sorghum is particularly vital given the current ecological, environmental, and agricultural challenges exacerbated by climate change. As sorghum is one of the main staple foods of our region and is known to be a resilient crop with a high potential to overcome the above challenges, the application of genome editing technology will enhance the investigation of gene functionality. CRISPR/Cas9 enables the improvement of desirable sorghum traits, including nutritional value, yield, resistance to pests and diseases, and tolerance to various abiotic stresses. Furthermore, CRISPR/Cas9 has the potential to perform intricate editing and reshape the existing elite sorghum varieties, and introduce new genetic variations. However, current research primarily focuses on improving the efficacy of the CRISPR/Cas9 system in successfully editing endogenous sorghum genes, making it a feasible and successful undertaking in sorghum improvement. Recent advancements and developments in CRISPR/Cas9 techniques have further empowered researchers to modify additional genes in sorghum with greater efficiency. Successful application and advancement of CRISPR techniques in sorghum will aid not only in gene discovery and the creation of novel traits that regulate gene expression and functional genomics but also in facilitating site-specific integration events. The purpose of this review is, therefore, to elucidate the current advances in sorghum genome editing and highlight its potential in addressing food security issues. It also assesses the efficiency of CRISPR-mediated improvement and its long-term effects on crop improvement and host resistance against parasites, including tissue-specific activity and the ability to induce resistance. This review ends by emphasizing the challenges and opportunities of CRISPR technology in combating parasitic plants and proposing directions for future research to safeguard global agricultural productivity.

Keywords: CRISPR/Cas9, genome editing, quality, sorghum, stress, yield

Procedia PDF Downloads 27
274 Envy and Schadenfreude Domains in a Model of Neurodegeneration

Authors: Hernando Santamaría-García, Sandra Báez, Pablo Reyes, José Santamaría-García, Diana Matallana, Adolfo García, Agustín Ibañez

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The study of moral emotions (i.e., Schadenfreude and envy) is critical to understand the ecological complexity of everyday interactions between cognitive, affective, and social cognition processes. Most previous studies in this area have used correlational imaging techniques and framed Schadenfreude and envy as monolithic domains. Here, we profit from a relevant neurodegeneration model to disentangle the brain regions engaged in three dimensions of Schadenfreude and envy: deservingness, morality, and legality. We tested 20 patients with behavioral variant frontotemporal dementia (bvFTD), 24 patients with Alzheimer’s disease (AD), as a contrastive neurodegeneration model, and 20 healthy controls on a novel task highlighting each of these dimensions in scenarios eliciting Schadenfreude and envy. Compared with the AD and control groups, bvFTD patients obtained significantly higher scores on all dimensions for both emotions. Interestingly, the legal dimension for both envy and Schadenfreude elicited higher emotional scores than the deservingness and moral dimensions. Furthermore, correlational analyses in bvFTD showed that higher envy and Schadenfreude scores were associated with greater deficits in social cognition, inhibitory control, and behavior. Brain anatomy findings (restricted to bvFTD and controls) confirmed differences in how these groups process each dimension. Schadenfreude was associated with the ventral striatum in all subjects. Also, in bvFTD patients, increased Schadenfreude across dimensions was negatively correlated with regions supporting social-value rewards, mentalizing, and social cognition (frontal pole, temporal pole, angular gyrus and precuneus). In all subjects, all dimensions of envy positively correlated with the volume of the anterior cingulate cortex, a region involved in processing unfair social comparisons. By contrast, in bvFTD patients, the intensified experience of envy across all dimensions was negatively correlated with a set of areas subserving social cognition, including the prefrontal cortex, the parahippocampus, and the amygdala. Together, the present results provide the first lesion-based evidence for the multidimensional nature of the emotional experiences of envy and Schadenfreude. Moreover, this is the first demonstration of a selective exacerbation of envy and Schadenfreude in bvFTD patients, probably triggered by atrophy to social cognition networks. Our results offer new insights into the mechanisms subserving complex emotions and moral cognition in neurodegeneration, paving the way for groundbreaking research on their interaction with other cognitive, social, and emotional processes.

Keywords: social cognition, moral emotions, neuroimaging, frontotemporal dementia

Procedia PDF Downloads 283
273 Clinical Nursing Experience in Managing a Uterine Cancer Patient with Psychogenic Shock During the Extracorporeal Membrane Oxygenation Weaning Process

Authors: Syue-Wen Lin

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Objective: This article discusses the nursing experience of caring for a uterine cancer patient who experienced cardiogenic shock and was weaned off ECMO. The patient was placed on ECMO due to cardiogenic shock and initially struggled with anxiety caused by the physical discomfort from the disease and multiple medical devices, as well as the isolation in the ICU and restrictions on physical activity. Over time, the patient was able to wean off ECMO and perform daily activities and rehabilitation independently. Methods: The nursing period was from January 6 to January 9. Through observation, direct care, interviews, physical assessments, and case reviews, the intensive care team and bypass personnel conducted a comprehensive assessment using Gordon's 11 functional health patterns. The assessment identified three main nursing health problems: pain, anxiety, and decreased cardiac tissue perfusion. Results: The author consulted a psychologist to employ open communication techniques and empathetic care to build a trusting nurse-patient relationship. A patient-centered intensive cancer care plan was developed. Pain was assessed using a pain scale, and pain medications were adjusted in consultation with a pharmacist. Lavender essential oil therapy, light music, and pillows were used to distract and alleviate pain. The patient was encouraged to express feelings and family members were invited to increase visits and provide companionship to reduce the uncertainty caused by cancer and illness. Vital signs were closely monitored, and nursing interventions were provided to maintain adequate myocardial perfusion. Post-ECMO, the patient was encouraged to engage in rehabilitation and cardiopulmonary training. Conclusion: A key takeaway from the care process is the importance of observing not only the patient's vital signs but also their psychological state, especially when dealing with cancer patients on ECMO. The patient's greatest source of comfort was the presence of family, which helped alleviate anxiety. Healthcare providers play multiple critical roles as advocates, coordinators, educators, and counselors, listening to and accepting the patient’s emotional responses. The report aims to provide clinical cancer nurses with a reference to improve the quality of care and alleviate cancer-related discomfort.

Keywords: ECMO, uterine cancer, palliative care, Gordon's 11 functional health patterns

Procedia PDF Downloads 19
272 Deep Learning for Image Correction in Sparse-View Computed Tomography

Authors: Shubham Gogri, Lucia Florescu

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Medical diagnosis and radiotherapy treatment planning using Computed Tomography (CT) rely on the quantitative accuracy and quality of the CT images. At the same time, requirements for CT imaging include reducing the radiation dose exposure to patients and minimizing scanning time. A solution to this is the sparse-view CT technique, based on a reduced number of projection views. This, however, introduces a new problem— the incomplete projection data results in lower quality of the reconstructed images. To tackle this issue, deep learning methods have been applied to enhance the quality of the sparse-view CT images. A first approach involved employing Mir-Net, a dedicated deep neural network designed for image enhancement. This showed promise, utilizing an intricate architecture comprising encoder and decoder networks, along with the incorporation of the Charbonnier Loss. However, this approach was computationally demanding. Subsequently, a specialized Generative Adversarial Network (GAN) architecture, rooted in the Pix2Pix framework, was implemented. This GAN framework involves a U-Net-based Generator and a Discriminator based on Convolutional Neural Networks. To bolster the GAN's performance, both Charbonnier and Wasserstein loss functions were introduced, collectively focusing on capturing minute details while ensuring training stability. The integration of the perceptual loss, calculated based on feature vectors extracted from the VGG16 network pretrained on the ImageNet dataset, further enhanced the network's ability to synthesize relevant images. A series of comprehensive experiments with clinical CT data were conducted, exploring various GAN loss functions, including Wasserstein, Charbonnier, and perceptual loss. The outcomes demonstrated significant image quality improvements, confirmed through pertinent metrics such as Peak Signal-to-Noise Ratio (PSNR) and Structural Similarity Index (SSIM) between the corrected images and the ground truth. Furthermore, learning curves and qualitative comparisons added evidence of the enhanced image quality and the network's increased stability, while preserving pixel value intensity. The experiments underscored the potential of deep learning frameworks in enhancing the visual interpretation of CT scans, achieving outcomes with SSIM values close to one and PSNR values reaching up to 76.

Keywords: generative adversarial networks, sparse view computed tomography, CT image correction, Mir-Net

Procedia PDF Downloads 153
271 Utilization of Chicken Skin Based Products as Fat Replacers for Improving the Nutritional Quality, Physico-Chemical Characteristics and Sensory Attributes of Beef Fresh Sausage

Authors: Hussein M. H. Mohamed, Hamdy M. B. Zaki

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Fresh sausage is one of the cheapest and delicious meat products that are gaining popularity all over the world. It is considered as a practice of adding value to low-value meat cuts of high fat and connective tissue contents. One of the most important characteristics of fresh sausage is the distinctive marbling appearance between lean and fatty portions, which can be achieved by using animal fat. For achieving the marbling appearance of fresh sausage, a lager amount of fat needs to be used. The use of animal fat may represent a health concern due to its content of saturated fatty acids and trans-fats, which increase the risk of heart diseases. There is a need for reducing the fat content of fresh sausage to obtain a healthy product. However, fat is responsible for the texture, flavor, and juiciness of the product. Therefore, developing reduced-fat products is a challenging process. The main objectives of the current study were to incorporate chicken skin based products (chicken skin emulsion, gelatinized chicken skin, and gelatinized chicken skin emulsion) during the formulation of fresh sausage as fat replacers and to study the effect of these products on the nutritional quality, physicochemical properties, and sensory attributes of the processed product. Three fresh sausage formulae were prepared using chicken skin based fat replacers (chicken skin emulsion, gelatinized chicken skin, and gelatinized chicken skin emulsion) beside one formula prepared using mesenteric beef fat as a control. The proximate composition, fatty acid profiles, Physico-chemical characteristics, and sensory attributes of all formulas were assessed. The results revealed that the use of chicken skin based fat replacers resulted in significant (P < 0.05) reduction of fat contents from 17.67 % in beef mesenteric fat formulated sausage to 5.77, 8.05 and 8.46 in chicken skin emulsion, gelatinized chicken skin, and gelatinized chicken skin emulsion formulated sausages, respectively. Significant reduction in the saturated fatty acid contents and a significant increase in mono-unsaturated, poly-unsaturated, and omega-3 fatty acids have been observed in all formulae processed with chicken skin based fat replacers. Moreover, significant improvements in the physico-chemical characteristics and non-significant changes in the sensory attributes have been obtained. From the obtained results, it can be concluded that the chicken skin based products can be used safely to improve the nutritional quality and physico chemical properties of beef fresh sausages without changing the sensory attributes of the product. This study may encourage meat processors to utilize chicken skin based fat replacers for the production of high quality and healthy beef fresh sausages.

Keywords: chicken skin emulsion, fresh sausage, gelatinized chicken skin, gelatinized chicken skin emulsion

Procedia PDF Downloads 126
270 Development of Perovskite Quantum Dots Light Emitting Diode by Dual-Source Evaporation

Authors: Antoine Dumont, Weiji Hong, Zheng-Hong Lu

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Light emitting diodes (LEDs) are steadily becoming the new standard for luminescent display devices because of their energy efficiency and relatively low cost, and the purity of the light they emit. Our research focuses on the optical properties of the lead halide perovskite CsPbBr₃ and its family that is showing steadily improving performances in LEDs and solar cells. The objective of this work is to investigate CsPbBr₃ as an emitting layer made by physical vapor deposition instead of the usual solution-processed perovskites, for use in LEDs. The deposition in vacuum eliminates any risk of contaminants as well as the necessity for the use of chemical ligands in the synthesis of quantum dots. Initial results show the versatility of the dual-source evaporation method, which allowed us to create different phases in bulk form by altering the mole ratio or deposition rate of CsBr and PbBr₂. The distinct phases Cs₄PbBr₆, CsPbBr₃ and CsPb₂Br₅ – confirmed through XPS (x-ray photoelectron spectroscopy) and X-ray diffraction analysis – have different optical properties and morphologies that can be used for specific applications in optoelectronics. We are particularly focused on the blue shift expected from quantum dots (QDs) and the stability of the perovskite in this form. We already obtained proof of the formation of QDs through our dual source evaporation method with electron microscope imaging and photoluminescence testing, which we understand is a first in the community. We also incorporated the QDs in an LED structure to test the electroluminescence and the effect on performance and have already observed a significant wavelength shift. The goal is to reach 480nm after shifting from the original 528nm bulk emission. The hole transport layer (HTL) material onto which the CsPbBr₃ is evaporated is a critical part of this study as the surface energy interaction dictates the behaviour of the QD growth. A thorough study to determine the optimal HTL is in progress. A strong blue shift for a typically green emitting material like CsPbBr₃ would eliminate the necessity of using blue emitting Cl-based perovskite compounds and could prove to be more stable in a QD structure. The final aim is to make a perovskite QD LED with strong blue luminescence, fabricated through a dual-source evaporation technique that could be scalable to industry level, making this device a viable and cost-effective alternative to current commercial LEDs.

Keywords: material physics, perovskite, light emitting diode, quantum dots, high vacuum deposition, thin film processing

Procedia PDF Downloads 159
269 Nacre Deposition Rate in Japanese and Hybrid Mother Oysters, Pinctada Fucata, and Its Relationship with Their Respective Pearls

Authors: Gunawan Muhammad, Takashi Atsumi, Akira Komaru

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Pinctada fucata has been the most important pearl culture species in Japan and known as Japanese Akoya Pearl Oyster. However, during summer 1994, mass mortality devastated pearl culture in most parts of Japan. Therefore, pearl farmers started to import Chinese Pearl Oysters from Hainan Island that came from the same species because they are believed to be more resistant towards high water temperature, despite their lack of ability in producing high-quality pearls. The local farmers were then hybridized Japanese and Chinese pearl oysters and currently known as Hybrid pearl oysters, as an attempt to produce a new oyster's strain which is more resistant towards high temperature but also able to produce higher quality pearls. However, despite both strains were implanted by mantle tissues from the same group of donors, the thickness of pearl nacre produced by both strains was different, even though tablet thickness shows a rather similar pattern. Hence, this leads to a question of whether mother oysters play a major role in both nacre deposition rate and tablet thickness of pearls or not. This study first describes the nacre deposition rate of the shells of Japanese and Hybrid mother oysters towards the water temperature condition in Ago Bay, Mie Prefecture, Japan. Later, a comparative study was conducted among 4 shell positions that had been chosen according to the mantle tissue location and shell growth directions. A correlative study was then taken between shells and pearls nacre deposition rate to know whether mother oyster ability in depositing nacre on their shells is related to that of pearls. All the four shell positions were significantly different in shell nacre growth rate (Kruskal-Wallis, p-value < 0.05), and the third position have faster nacre growth among the other three both in Japanese and Hybrid strains, especially in warm temperature. The ability to deposit nacre between Japanese and Hybrid during warm water conditions (August and September) is also significantly different in almost all positions (Mann Whitney U, p-value < 0.01), Japanese oyster growth faster than Hybrid in all four positions. This leads to a different total growth among the two strains and a higher possibility of thicker nacre thickness in Japanese shell nacre. Tablet thickness is significantly different among all positions of shells (Kruskal-Wallis, p-value < 0.01), the 2nd position deposited rather thinner tablet thickness than the other three, including on the 6th month of culture which is more desirable in producing pearls with good luster. This result gives us new information that pearl growth rate is highly affected by the mother oysters; however, nacre tablet thickness might be the result of the shell matrix expressed by different mantle position from donor oysters.

Keywords: nacre, deposition, biomineralization, pearl aquaculture, pearl oyster, Akoya pearl, pearl

Procedia PDF Downloads 135
268 Use of Satellite Altimetry and Moderate Resolution Imaging Technology of Flood Extent to Support Seasonal Outlooks of Nuisance Flood Risk along United States Coastlines and Managed Areas

Authors: Varis Ransibrahmanakul, Doug Pirhalla, Scott Sheridan, Cameron Lee

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U.S. coastal areas and ecosystems are facing multiple sea level rise threats and effects: heavy rain events, cyclones, and changing wind and weather patterns all influence coastal flooding, sedimentation, and erosion along critical barrier islands and can strongly impact habitat resiliency and water quality in protected habitats. These impacts are increasing over time and have accelerated the need for new tracking techniques, models and tools of flood risk to support enhanced preparedness for coastal management and mitigation. To address this issue, NOAA National Ocean Service (NOS) evaluated new metrics from satellite altimetry AVISO/Copernicus and MODIS IR flood extents to isolate nodes atmospheric variability indicative of elevated sea level and nuisance flood events. Using de-trended time series of cross-shelf sea surface heights (SSH), we identified specific Self Organizing Maps (SOM) nodes and transitions having a strongest regional association with oceanic spatial patterns (e.g., heightened downwelling favorable wind-stress and enhanced southward coastal transport) indicative of elevated coastal sea levels. Results show the impacts of the inverted barometer effect as well as the effects of surface wind forcing; Ekman-induced transport along broad expanses of the U.S. eastern coastline. Higher sea levels and corresponding localized flooding are associated with either pattern indicative of enhanced on-shore flow, deepening cyclones, or local- scale winds, generally coupled with an increased local to regional precipitation. These findings will support an integration of satellite products and will inform seasonal outlook model development supported through NOAAs Climate Program Office and NOS office of Center for Operational Oceanographic Products and Services (CO-OPS). Overall results will prioritize ecological areas and coastal lab facilities at risk based on numbers of nuisance flood projected and inform coastal management of flood risk around low lying areas subjected to bank erosion.

Keywords: AVISO satellite altimetry SSHA, MODIS IR flood map, nuisance flood, remote sensing of flood

Procedia PDF Downloads 138
267 Occult Haemolacria Paradigm in the Study of Tears

Authors: Yuliya Huseva

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To investigate the contents of tears to determine latent blood. Methods: Tear samples from 72 women were studied with the microscopy of tears aspirated with a capillary and stained by Nocht and with a chemical method of test strips with chromogen. Statistical data processing was carried out using statistical packages Statistica 10.0 for Windows, calculation of Pearson's chi-square test, Yule association coefficient, the method of determining sensitivity and specificity. Results:, In 30.6% (22) of tear samples erythrocytes were revealed microscopically. Correlations between the presence of erythrocytes in the tear and the phase of the menstrual cycle has been discovered. In the follicular phase of the cycle, erythrocytes were found in 59.1% (13) people, which is significantly more (x2=4.2, p=0.041) compared to the luteal phase - in 40.9% (9) women. In the first seven days of the follicular phase of the menstrual cycle the erythrocytes were predominanted of in the tears of women examined testifies in favour of the vicarious bleeding from the mucous membranes of extragenital organs in sync with menstruation. Of the other cellular elements in tear samples with latent haemolacria, neutrophils prevailed - in 45.5% (10), while lymphocytes were less common - in 27.3% (6), because neutrophil exudation is accompanied by vasodilatation of the conjunctiva and the release of erythrocytes into the conjunctival cavity. It was found that the prognostic significance of the chemical method was 0.53 of the microscopic method. In contrast to microscopy, which detected blood in tear samples from 30.6% (22) of women, blood was detected chemically in tears of 16.7% (12). An association between latent haemolacria and endometriosis was found (k=0.75, p≤0.05). Microscopically, in the tears of patients with endometriosis, erythrocytes were detected in 70% of cases, while in healthy women without endometriosis - in 25% of cases. The proportion of women with erythrocytes in tears, determined by a chemical method, was 41.7% among patients with endometriosis, which is significantly more (x2=6.5, p=0.011) than 11.7% among women without endometriosis. The data obtained can be explained by the etiopathogenesis of the extragenital endometriosis which is caused by hematogenous spread of endometrial tissue into the orbit. In endometriosis, erythrocytes are found against the background of accumulations of epithelial cells. In the tear samples of 4 women with endometriosis, glandular cuboidal epithelial cells, morphologically similar to endometrial cells, were found, which may indicate a generalization of the disease. Conclusions: Single erythrocytes can normally be found in the tears, their number depends on the phase of the menstrual cycle, increasing in the follicular phase. Erythrocytes found in tears against the background of accumulations of epitheliocytes and their glandular atypia may indicate a manifestation of extragenital endometriosis. Both used methods (microscopic and chemical) are informative in revealing latent haemolacria. The microscopic method is more sensitive, reveals intact erythrocytes, and besides, it provides information about other cells. At the same time, the chemical method is faster and technically simpler, it determines the presence of haemoglobin and its metabolic products, and can be used as a screening.

Keywords: tear, blood, microscopy, epitheliocytes

Procedia PDF Downloads 117
266 Medial Temporal Tau Predicts Memory Decline in Cognitively Unimpaired Elderly

Authors: Angela T. H. Kwan, Saman Arfaie, Joseph Therriault, Zahra Azizi, Firoza Z. Lussier, Cecile Tissot, Mira Chamoun, Gleb Bezgin, Stijn Servaes, Jenna Stevenon, Nesrine Rahmouni, Vanessa Pallen, Serge Gauthier, Pedro Rosa-Neto

Abstract:

Alzheimer’s disease (AD) can be detected in living people using in vivo biomarkers of amyloid-β (Aβ) and tau, even in the absence of cognitive impairment during the preclinical phase. [¹⁸F]-MK-6420 is a high affinity positron emission tomography (PET) tracer that quantifies tau neurofibrillary tangles, but its ability to predict cognitive changes associated with early AD symptoms, such as memory decline, is unclear. Here, we assess the prognostic accuracy of baseline [18F]-MK-6420 tau PET for predicting longitudinal memory decline in asymptomatic elderly individuals. In a longitudinal observational study, we evaluated a cohort of cognitively normal elderly participants (n = 111) from the Translational Biomarkers in Aging and Dementia (TRIAD) study (data collected between October 2017 and July 2020, with a follow-up period of 12 months). All participants underwent tau PET with [¹⁸F]-MK-6420 and Aβ PET with [¹⁸F]-AZD-4694. The exclusion criteria included the presence of head trauma, stroke, or other neurological disorders. There were 111 eligible participants who were chosen based on the availability of Aβ PET, tau PET, magnetic resonance imaging (MRI), and APOEε4 genotyping. Among these participants, the mean (SD) age was 70.1 (8.6) years; 20 (18%) were tau PET positive, and 71 of 111 (63.9%) were women. A significant association between baseline Braak I-II [¹⁸F]-MK-6240 SUVR positivity and change in composite memory score was observed at the 12-month follow-up, after correcting for age, sex, and years of education (Logical Memory and RAVLT, standardized beta = -0.52 (-0.82-0.21), p < 0.001, for dichotomized tau PET and -1.22 (-1.84-(-0.61)), p < 0.0001, for continuous tau PET). Moderate cognitive decline was observed for A+T+ over the follow-up period, whereas no significant change was observed for A-T+, A+T-, and A-T-, though it should be noted that the A-T+ group was small.Our results indicate that baseline tau neurofibrillary tangle pathology is associated with longitudinal changes in memory function, supporting the use of [¹⁸F]-MK-6420 PET to predict the likelihood of asymptomatic elderly individuals experiencing future memory decline. Overall, [¹⁸F]-MK-6420 PET is a promising tool for predicting memory decline in older adults without cognitive impairment at baseline. This is of critical relevance as the field is shifting towards a biological model of AD defined by the aggregation of pathologic tau. Therefore, early detection of tau pathology using [¹⁸F]-MK-6420 PET provides us with the hope that living patients with AD may be diagnosed during the preclinical phase before it is too late.

Keywords: alzheimer’s disease, braak I-II, in vivo biomarkers, memory, PET, tau

Procedia PDF Downloads 73
265 Depressive-Like Behavior in a Murine Model of Colorectal Cancer Associated with Altered Cytokine Levels in Stress-Related Brain Regions

Authors: D. O. Miranda, L. R. Azevedo, J. F. C. Cordeiro, A. H. Dos Santos, S. F. Lisboa, F. S. Guimarães, G. S. Bisson

Abstract:

Background: The Colorectal cancer (CRC) is one of the most common cancers and the fourth leading cause of cancer death in the world. The prevalence of psychiatric-disorders among CRC patients, mainly depression, is high, resulting in impaired quality of life and side effects of primary treatment. High levels of proinflammatory cytokines at tumor microenvironment is a feature of CRC and the literature suggests that those mediators could contribute to the development of psychiatric disorders. Nevertheless, the ability of tumor-associated biological processes to affect the central nervous system (CNS) has only recently been explored in the context of symptoms of depression and is still not well understood. Therefore, the aim of the present study was to test the hypothesis that depressive-like behavior in an experimental model of CCR induced by N-methyl-N-nitro-N-nitrosoguanidine (MNNG) was correlated to proinflammatory profile in the periphery and in the brain. Methods: Colorectal carcinogenesis was induced in adult C57BL/6 mice (n=12) by administration of MNNG (5mg/kg, 0.1ml/intrarectal instillation) 2 times a week, for 2 week. Control group (n=12) received saline (0.1ml/intrarectal instillation). Eight weeks after beginning of MNNG administration animals were submitted to the forced swim test (FST) and the sucrose preference test for evaluation, respectively, of depressive- and anhedonia-like behaviors. After behavioral evaluation, the colon was collected and brain regions dissected (cortex-C, striatum-ST and hippocampus-HIP) for posterior evaluation of cytokine levels (IL-1β, IL-10, IL-17, and CX3CL1) by ELISA. Results: MNNG induced depressive-like behavior, represented by increased immobility time in the FST (Student t test, p < 0.05) and lower sucrose preference (Student t test, p < 0.05). Moreover, there were increased levels of IL-1β, IL-17 and CX3CL1 in the colonic tissue (Student t test, p < 0.05) and in the brain (IL-1 β in the ST and HIP, Student t test, p < 0.05; IL-17 and CX3CL1 in the C and HIP, p < 0.05). IL-10 levels, in contrast, were decreased in both the colon (p < 0.05) and the brain (C and HIP, p < 0.05). Conclusions: The results obtained in the present work support the notion that tumor growth induces neuroinflammation in stress-related brain regions and depressive-like behavior, which could be related to the high incidence of depression in colorectal carcinogenesis. This work have important clinical and research implications, taken into account that cytokine levels may be a marker promissory for the developing depression in CRC patients. New therapeutic strategies to assist in alleviating mental suffering in cancer patients might result from a better understanding of the role of cytokines in the pathophysiology of depression in these subjects.

Keywords: cytokines, brain, depression, colorectal cancer

Procedia PDF Downloads 268
264 iPSC-derived MSC Mediated Immunosuppression during Mouse Airway Transplantation

Authors: Mohammad Afzal Khan, Fatimah Alanazi, Hala Abdalrahman Ahmed, Talal Shamma, Kilian Kelly, Mohammed A. Hammad, Abdullah O. Alawad, Abdullah Mohammed Assiri, Dieter Clemens Broering

Abstract:

Lung transplantation is a life-saving surgical replacement of diseased lungs in patients with end-stage respiratory malfunctions. Despite the remarkable short-term recovery, long-term lung survival continues to face several significant challenges, including chronic rejection and severe toxic side-effects due to global immunosuppression. Stem cell-based immunotherapy has been recognized as a crucial immunoregulatory regimen in various preclinical and clinical studies. Despite initial therapeutic outcomes, conventional stem cells face key limitations. The Cymerus™ manufacturing facilitates the production of a virtually limitless supply of consistent human induced pluripotent stem cell (iPSC)-derived mesenchymal stem cells, which could play a key role in selective immunosuppression and graft repair during rejection. Here, we demonstrated the impact of iPSC-derived human MSCs on the development of immune-tolerance and long-term graft survival in mouse orthotopic airway allografts. BALB/c→C57BL/6 allografts were reconstituted with iPSC-derived MSCs (2 million/transplant/ at d0), and allografts were examined for regulatory T cells (Tregs), oxygenation, microvascular blood flow, airway epithelium and collagen deposition during rejection. We demonstrated that iPSC-derived MSC treatment leads to significant increase in tissue expression of hTSG-6 protein, followed by an upregulation of mouse Tregs and IL-5, IL-10, IL-15 cytokines, which augments graft microvascular blood flow and oxygenation, and thereby maintained a healthy airway epithelium and prevented the subepithelial deposition of collagen at d90 post-transplantation. Collectively, these data confirmed that iPSC-derived MSC-mediated immunosuppression has potential to establish immune-tolerance and rescue allograft from sustained hypoxic/ischemic phase and subsequently limits long-term airway epithelial injury and collagen progression, which therapeutically warrant a study of Cymerus iPSC-derived MSCs as a potential management option for immunosuppression in transplant recipients.

Keywords: stem cell therapy, immunotolerance, regulatory T cells, hypoxia and ischemia, microvasculature

Procedia PDF Downloads 156
263 Can Zirconia Wings of Resin Retained Cantilever Bridges Be Effectively Bonded To Tooth Tissue When Compared With Metal Wings In The Anterior Dentition in vivo? - A Systematic Review.

Authors: Ariyan S. Araghi, Guy C. Jackson, Stephen J. Bonsor

Abstract:

Materials & Methods: A systematic literature search was undertaken using pre-determined inclusion and exclusion criteria. This review followed the Preferred Reporting Items for Systemic Reviews and Meta-Analysis (PRISMA) statement. Several databases were used to search for randomised control trials and longitudinal cohort studies, which were published less than thirty years ago. A total of 54 studies met the predefined inclusion criteria. Four studies reviewed the success, survival, and failure characteristics of zirconia framework resin retained bridges, whilst two reviewed non-precious metal resin retained bridges. Results: The analysis of the studies revealed an overall survival rate of 95.9% for zirconia-based restorations compared to 90.7% for non-precious metal frameworks. Non-precious metal resin retained bridges displayed a higher overall failure rate of 11.9% compared to 4.6% for zirconia-based restorations in the analysed papers. The most frequent complications were wing debonding for the non-precious metal wing group, whereas substructure fracture and veneering ceramic fracture were more prevalent for the zirconia arm of the study. Conclusion: Both types of resin retained bridges provide effective medium to long-term survival. Zirconia-based frameworks will provide marginally increased success and survival and greatly improved aesthetics. However, catastrophic failure is more likely with zirconia-based restorations. Non-precious metal is time tested but performs worse than its zirconia counterpart with regards to longevity; it does not exhibit the same framework fractures as zirconia. Cement choice and attention to the adhesive bonding systems used appear to be paramount to restoration longevity with both restoration subtypes. Furthermore, improved longevity can be seen when air particle abrasion is incorporated into the adhesive protocol. Within the limitations of this study, it has been determined that zirconia-based resin retained bridges can be effectively used in anterior cantilever bridges. Clinical Significance: Zirconia-based resin retained bridges have been demonstrating promising results in terms of improved success and survival characteristics, together with improved aesthetics when compared to non-precious metal winged resin retained bridges. Their popularity is increasing in the age of digital dentistry as many restorations are manufactured using such technology. It is essential that clinicians understand the limitations of each material type and principles of adhesion to ensure restoration longevity.

Keywords: resin retained bridge, fixed partial denture, zirconia bridge, adhesive bridge

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262 Using the Micro Computed Tomography to Study the Corrosion Behavior of Magnesium Alloy at Different pH Values

Authors: Chia-Jung Chang, Sheng-Che Chen, Ming-Long Yeh, Chih-Wei Wang, Chih-Han Chang

Abstract:

Introduction and Motivation: In recent years, magnesium alloy is used to be a kind of medical biodegradable materials. Magnesium is an essential element in the body and is efficiently excreted by the kidneys. Furthermore, the mechanical properties of magnesium alloy is closest to human bone. However, in some cases magnesium alloy corrodes so quickly that it would release hydrogen on surface of implant. The other product is hydroxide ion, it can significantly increase the local pH value. The above situations may have adverse effects on local cell functions. On the other hand, nowadays magnesium alloy corrode too fast to maintain the function of implant until the healing of tissue. Therefore, much recent research about magnesium alloy has focused on controlling the corrosion rate. The in vitro corrosion behavior of magnesium alloys is affected by many factors, and pH value is one of factors. In this study, we will study on the influence of pH value on the corrosion behavior of magnesium alloy by the Micro-CT (micro computed tomography) and other instruments.Material and methods: In the first step, we make some guiding plates for specimens of magnesium alloy AZ91 by Rapid Prototyping. The guiding plates are able to be a standard for the degradation of specimen, so that we can use it to make sure the position of specimens in the CT image. We can also simplify the conditions of degradation by the guiding plates.In the next step, we prepare the solution with different pH value. And then we put the specimens into the solution to start the corrosion test. The CT image, surface photographs and weigh are measured on every twelve hours. Results: In the primary results of the test, we make sure that CT image can be a way to quantify the corrosion behavior of magnesium alloy. Moreover we can observe the phenomenon that corrosion always start from some erosion point. It’s possibly based on some defect like dislocations and the voids with high strain energy in the materials. We will deal with the raw data into Mass Loss (ML) and corrosion rate by CT image, surface photographs and weigh in the near future. Having a simple prediction, the pH value and degradation rate will be negatively correlated. And we want to find out the equation of the pH value and corrosion rate. We also have a simple test to simulate the change of the pH value in the local region. In this test the pH value will rise to 10 in a short time. Conclusion: As a biodegradable implant for the area with stagnating body fluid flow in the human body, magnesium alloy can cause the increase of local pH values and release the hydrogen. Those may damage the human cell. The purpose of this study is finding out the equation of the pH value and corrosion rate. After that we will try to find the ways to overcome the limitations of medical magnesium alloy.

Keywords: magnesium alloy, biodegradable materials, corrosion, micro-CT

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261 Combined Effect of Vesicular System and Iontophoresis on Skin Permeation Enhancement of an Analgesic Drug

Authors: Jigar N. Shah, Hiral J. Shah, Praful D. Bharadia

Abstract:

The major challenge faced by formulation scientists in transdermal drug delivery system is to overcome the inherent barriers related to skin permeation. The stratum corneum layer of the skin is working as the rate limiting step in transdermal transport and reduce drug permeation through skin. Many approaches have been used to enhance the penetration of drugs through this layer of the skin. The purpose of this study is to investigate the development and evaluation of a combined approach of drug carriers and iontophoresis as a vehicle to improve skin permeation of an analgesic drug. Iontophoresis is a non-invasive technique for transporting charged molecules into and through tissues by a mild electric field. It has been shown to effectively deliver a variety of drugs across the skin to the underlying tissue. In addition to the enhanced continuous transport, iontophoresis allows dose titration by adjusting the electric field, which makes personalized dosing feasible. Drug carrier could modify the physicochemical properties of the encapsulated molecule and offer a means to facilitate the percutaneous delivery of difficult-to-uptake substances. Recently, there are some reports about using liposomes, microemulsions and polymeric nanoparticles as vehicles for iontophoretic drug delivery. Niosomes, the nonionic surfactant-based vesicles that are essentially similar in properties to liposomes have been proposed as an alternative to liposomes. Niosomes are more stable and free from other shortcoming of liposomes. Recently, the transdermal delivery of certain drugs using niosomes has been envisaged and niosomes have proved to be superior transdermal nanocarriers. Proniosomes overcome some of the physical stability related problems of niosomes. The proniosomal structure was liquid crystalline-compact niosomes hybrid which could be converted into niosomes upon hydration. The combined use of drug carriers and iontophoresis could offer many additional benefits. The system was evaluated for Encapsulation Efficiency, vesicle size, zeta potential, Transmission Electron Microscopy (TEM), DSC, in-vitro release, ex-vivo permeation across skin and rate of hydration. The use of proniosomal gel as a vehicle for the transdermal iontophoretic delivery was evaluated in-vitro. The characteristics of the applied electric current, such as density, type, frequency, and on/off interval ratio were observed. The study confirms the synergistic effect of proniosomes and iontophoresis in improving the transdermal permeation profile of selected analgesic drug. It is concluded that proniosomal gel can be used as a vehicle for transdermal iontophoretic drug delivery under suitable electric conditions.

Keywords: iontophoresis, niosomes, permeation enhancement, transdermal delivery

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260 Technology Changing Senior Care

Authors: John Kosmeh

Abstract:

Introduction – For years, senior health care and skilled nursing facilities have been plagued with the dilemma of not having the necessary tools and equipment to adequately care for senior residents in their communities. This has led to high transport rates to emergency departments and high 30-day readmission rates, costing billions of unnecessary dollars each year, as well as quality assurance issues. Our Senior care telemedicine program is designed to solve this issue. Methods – We conducted a 1-year pilot program using our technology coupled with our 24/7 telemedicine program with skilled nursing facilities in different parts of the United States. We then compared transports rates and 30-day readmission rates to previous years before the use of our program, as well as transport rates of other communities of similar size not using our program. This data was able to give us a clear and concise look at the success rate of reducing unnecessary transport and readmissions as well as cost savings. Results – A 94% reduction nationally of unnecessary out-of-facility transports, and to date, complete elimination of 30-day readmissions. Our virtual platform allowed us to instruct facility staff on the utilization of our tools and system as well as deliver treatment by our ER-trained providers. Delay waiting for PCP callbacks was eliminated. We were able to obtain lung, heart, and abdominal ultrasound imaging, 12 lead EKG, blood labs, auscultate lung and heart sounds, and collect other diagnostic tests at the bedside within minutes, providing immediate care and allowing us to treat residents within the SNF. Are virtual capabilities allowed for loved ones, family members, and others who had medical power of attorney to virtually connect with us at the time of visit, to speak directly with the medical provider, providing increased confidence in the decision to treat the resident in-house. The decline in transports and readmissions will greatly reduce governmental cost burdens, as well as fines imposed on SNF for high 30-day readmissions, reduce the cost of Medicare A readmissions, and significantly impact the number of patients visiting overcrowded ERs. Discussion – By utilizing our program, SNF can effectively reduce the number of unnecessary transports of residents, as well as create significant savings from loss of day rates, transportation costs, and high CMS fines. The cost saving is in the thousands monthly, but more importantly, these facilities can create a higher quality of life and medical care for residents by providing definitive care instantly with ER-trained personnel.

Keywords: senior care, long term care, telemedicine, technology, senior care communities

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