Search results for: bovine bone

Authors: Connick K, Lalor R, Murphy A, O’Neill S. M., Rabab S. Zalat, Eman E. El Shanawany

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Cryptosporidium parvum is an opportunistic intracellular parasite that causes mild to severe diarrhea in human and animal populations and is an important zoonotic disease globally. In immunocompromised hosts, infection Canbe life-threatening as no effective treatments are currently available to control infection. To increase our understanding of the mechanisms that play a role in host-parasite interactions at the level of the immune response, we investigated the effects of Cryptosporidium parvum antigen (CPA) on bone marrow-derived (DCS). Herein we examined cytokine secretion and cell surface marker expression on DCs exposed to CPA. We also measured cytokine production in CD4+ cells co-cultured with CPA primed DCs in the presence of anti-CD3. CPA induced a significant increase in the production of interleukin(IL)-12p40, IL-10, IL-6, and TNF-α by DCs and enhanced the expression of the cell surface markers TLR4, CD80, CD86, and MHC11. CPA primed DC co-cultured in the presence of anti-CD3 with CD4+ T-cells inhibited the secretion of Th2 associated cytokines, notably IL-5 and IL-13, with no effects on the secretions of interferon (IFN)-γ, IL-2, IL-17, and IL-10. These findings support studies in the literature that CPA can induce the full maturation of DCs that subsequently initiate Th1 immune responses critical to the resolution of C. parvum infection.

Keywords: cryptosporidium parvum, dendritic cells, IL-12 p70, cell surface marker

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Authors: Adesoji Sodeinde

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Analytical derivatives has recently undergone an explosive growth in areas of separation techniques, likewise in detectability of certain compound/concentrated ions. The gloomy and depressing scenario which charaterized the application of analytical derivatives in areas of water analysis, water cycle and the environment should not be allowed to continue unabated. Due to technological advancement in various chemical/biochemical analysis separation techniques is widely used in areas of medical, forensic and to measure and assesses environment and social-economic impact of alternative control strategies. This technological improvement was dully established in the area of comparison between certain separation/detection techniques to bring about vital result in forensic[as Gas liquid chromatography reveals the evidence given in court of law during prosecution of drunk drivers]. The water quality analysis,pH and water temperature analysis can be performed in the field, the concentration of dissolved free amino-acid [DFAA] can also be detected through separation techniques. Some important derivatives/ions used in separation technique. Water analysis : Total water hardness [EDTA to determine ca and mg ions]. Gas liquid chromatography : innovative gas such as helium [He] or nitrogen [N] Water cycle : Animal bone charcoal,activated carbon and ultraviolet light [U.V light].

Keywords: analytical derivative, environment, water analysis, chemical/biochemical analysis

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Authors: Rima Zakzouk, Yasushi Shimada, Yuan Zhou, Yasunori Sumi, Junji Tagami

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Background and Purpose: Swept source optical coherence tomography (OCT) is an interferometric imaging technique that has been recently used in cariology. In spite of progress made in adhesive dentistry, the composite restoration has been failing due to secondary caries which occur due to environmental factors in oral cavities. Therefore, a precise assessment to effective marginal sealing of restoration is highly required. The aim of this study was evaluating gap formation at composite/cavity walls interface with or without phosphoric acid etching using SS-OCT. Materials and Methods: Round tapered cavities (2×2 mm) were prepared in three locations, mid-coronal, cervical, and root of bovine incisors teeth in two groups (SE and PA Groups). While self-etching adhesive (Clearfil SE Bond) was applied for the both groups, Group PA had been already pretreated with phosphoric acid etching (K-Etchant gel). Subsequently, both groups were restored by Estelite Flow Quick Flowable Composite Resin. Following 5000 thermal cycles, three cross-sectionals were obtained from each cavity using OCT at 1310-nm wavelength at 0°, 60°, 120° degrees. Scanning was repeated after two months to monitor the gap progress. Then the average percentage of gap length was calculated using image analysis software, and the difference of mean between both groups was statistically analyzed by t-test. Subsequently, the results were confirmed by sectioning and observing representative specimens under Confocal Laser Scanning Microscope (CLSM). Results: The results showed that pretreatment with phosphoric acid etching, Group PA, led to significantly bigger gaps in mid-coronal and cervical compared to SE group, while in the root cavity no significant difference was observed between both groups. On the other hand, the gaps formed in root’s cavities were significantly bigger than those in mid-coronal and cervical within the same group. This study investigated the effect of phosphoric acid on gap length progress on the composite restorations. In conclusions, phosphoric acid etching treatment did not reduce the gap formation even in different regions of the tooth. Significance: The cervical region of tooth was more exposing to gap formation than mid-coronal region, especially when we added pre-etching treatment.

Keywords: image analysis, optical coherence tomography, phosphoric acid etching, self-etch adhesives

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Authors: Joulié Aurélien, Jourdain Elsa, Bailly Xavier, Gasqui Patrick, Yang Elise, Leblond Agnès, Rousset Elodie, Sidi-Boumedine Karim

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Q fever is a worldwide zoonosis caused by the gram-negative obligate intracellular bacterium Coxiella burnetii. Following the recent outbreaks in the Netherlands, a hyper virulent clone was found to be the cause of severe human cases of Q fever. In livestock, Q fever clinical manifestations are mainly abortions. Although the abortion rates differ between ruminant species, C. burnetii’s virulence remains understudied, especially in enzootic areas. In this study, the infectious potential of three C. burnetii isolates collected from French farms of small ruminants were compared to the reference strain Nine Mile (in phase II and in an intermediate phase) using an in vivo (CD1 mice) model. Mice were challenged with 105 live bacteria discriminated by propidium monoazide-qPCR targeting the icd-gene. After footpad inoculation, spleen and popliteal lymph node were harvested at 10 days post-inoculation (p.i). The strain invasiveness in spleen and popliteal nodes was assessed by qPCR assays targeting the icd-gene. Preliminary results showed that the avirulent strains (in phase 2) failed to pass the popliteal barrier and then to colonize the spleen. This model allowed a significant differentiation between strain’s invasiveness on biological host and therefore identifying distinct virulence profiles. In view of these results, we plan to go further by testing fifteen additional C. burnetii isolates from French farms of sheep, goat and cattle by using the above-mentioned in vivo model. All 15 strains display distant MLVA (multiple-locus variable-number of tandem repeat analysis) genotypic profiles. Five of the fifteen isolates will bee also tested in vitro on ovine and bovine macrophage cells. Cells and supernatants will be harvested at day1, day2, day3 and day6 p.i to assess in vitro multiplication kinetics of strains. In conclusion, our findings might help the implementation of surveillance of virulent strains and ultimately allow adapting prophylaxis measures in livestock farms.

Keywords: Q fever, invasiveness, ruminant, virulence

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Authors: Himani Sharma, Amit Agrawal

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Stability of the Cassie and Wenzel wetting states depends on intrinsic contact angle and geometric features on a surface that was exploited in capturing biofluids in microwells. However, the mechanism of imbibition of biofluids in the microwells is not well implied in terms of wettability of a substrate. In this work, we experimentally demonstrated filling dynamics in hydrophilic and hydrophobic microwells by protein solutions. Towards this, we utilized lotus leaf as a mold to fabricate microwells on a Polydimethylsiloxane (PDMS) surface. Lotus leaf containing micrometer-sized blunt-conical shaped pillars with a height of 8-15 µm and diameter of 3-8 µm were transferred on to PDMS. Furthermore, PDMS surface was treated with oxygen plasma to render the hydrophilic nature. A 10µL droplets containing fluorescein isothiocyanate (FITC) - labelled bovine serum albumin (BSA) were rested on both hydrophobic (θa = 108o, where θa is the apparent contact angle) and hydrophilic (θa = 60o) PDMS surfaces. A time-dependent fluorescence microscopy was conducted on these modified PDMS surfaces by recording the fluorescent intensity over a 5 minute period. It was observed that, initially (at t=1 min) FITC-BSA was accumulated on the periphery of both hydrophilic and hydrophobic microwells due to incomplete penetration of liquid-gas meniscus. This deposition of FITC-BSA on periphery of microwell was not changed with time for hydrophobic surfaces, whereas, a complete filling was occurred in hydrophilic microwells (at t=5 mins). This attributes to a gradual movement of three-phase contact line along the vertical surface of the hydrophilic microwells as compared to stable pinning in the hydrophobic microwells as confirmed by Surface Evolver simulations. In addition, if the cavities are presented on hydrophobic surfaces, air bubbles will be trapped inside the cavities once the aqueous solution is placed over these surfaces, resulting in the Cassie-Baxter wetting state. This condition hinders trapping of proteins inside the microwells. Thus, it is necessary to impart hydrophilicity to the microwell surfaces so as to induce the Wenzel state, such that, an entire solution will be fully in contact with the walls of microwells. Imbibition of microwells by protein solutions was analyzed in terms fluorescent intensity versus time. The present work underlines the importance of geometry of microwells and surface wettability of substrate in wetting and effective capturing of solid sub-phases in biofluids.

Keywords: BSA, microwells, surface evolver, wettability

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Authors: Dr., Suchita Daokar

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Background: Successful orthodontic treatment has always relied on anchorage. The stability of the implants depends on bone quantity, mini-implant design, and placement conditions. Out of the various methods of gaining stability, Platelet concentrations are gaining popularity for various reasons. PRF is a minimally invasive method, and there are various studies that has shown its role in enhancing the stability of general implants. However, there is no literature found regarding the effect of PRF in enhancing the stability of the orthodontic implant. Therefore, this study aimed to evaluate and assess the efficacy of PRF on the stability of the orthodontic implant. Methods: The study comprised of 9 subjects aged above 18 years of age. The split mouth technique was used; Group A (where implants were coated before insertion) and group B (implant were normally inserted). The stability of the implant was measured using resonance frequency analysis at insertion (T0), 24 hours (T1), 2 weeks (T2), at 4 weeks (T3), at 6 weeks (T4), and 8 weeks (T5) after insertion. Result: Statistically significant findings were found when group A was compared to group B using ANOVA test (p<0.05). The stability of the implant of group A at each time interval was greater than group B. The implant stability was high at T0 and reduces at T2, and increasing through T3 to T5. The stability was highest at T5. Conclusion: A chairside, minimally invasive procedure ofPRF coating on implants have shown promising results in improving the stability of orthodontic implants and providing scope for future studies.

Keywords: Orthodontic implants, stablity, resonance Frequency Analysis, pre

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Authors: H. Bouaziz-Ketata, G. Ben Salah, Z. Aidi, C. Kallel, H. Kammoun, F. Fakhfakh, N. Zeghal

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The present study was performed to evaluate the potential protective effect of Hyparrhenia hirta methanolic extract in NaNO3-induced genotoxic and hematotoxic effects. Male Wistar rats were randomly divided into three groups: a control group and two treated groups during 50 days with NaNO3 administered at a dose of 400 mg kg-1 bw either alone in drinking water or co-administered with Hyparrhenia hirta at a dose of 200 mg kg-1 bw. NaNO3 treatment showed a significant increase in the frequencies of total chromosomal aberrations, aberrant metaphases and micronucleus in bone-marrow cells. In parallel, the NaNO3-treated group showed a significant decrease in red blood cell count, hemoglobin and hematocrit and a significant increase in total white blood cell, in neutrophil and eosinophil counts. Platelet count, mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration remained unchanged in treated groups compared to those of controls. Hyparrhenia hirta methanolic extract appeared to be effective against genotoxic and hematotoxic changes induced by nitrate, as evidenced by the improvement of the markers cited above.

Keywords: Hyparrhenia hirta, sodium nitrate, erythrocytes, genotoxicity

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Authors: Zhen Cao, Yu Zhu, Junxue Fu

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Immunoassay, i.e., antigen-antibody reaction, is crucial for disease diagnostics. To achieve the adequate signal of the antigen protein detection, a large amount of sample and long incubation time is needed. However, the amount of protein is usually small at the early stage, which makes it difficult to detect. Unlike cells and DNAs, no valid chemical method exists for protein amplification. Thus, an alternative way to improve the signal is through particle manipulation techniques to concentrate proteins, among which dielectrophoresis (DEP) is an effective one. DEP is a technique that concentrates particles to the designated region through a force created by the gradient in a non-uniform electric field. Since DEP force is proportional to the cube of particle size and square of electric field gradient, it is relatively easy to capture larger particles such as cells. For smaller ones like proteins, a super high gradient is then required. In this work, three-dimensional Ag/SiO2 nanorods arrays, fabricated by an easy physical vapor deposition technique called as oblique angle deposition, have been integrated with a DEP device and created the field gradient as high as of 2.6×10²⁴ V²/m³. The nanorods based DEP device is able to enrich bovine serum albumin (BSA) protein by 1800-fold and the rate has reached 180-fold/s when only applying 5 V electric potential. Based on the above nanorods integrated DEP platform, an immunoassay of mouse immunoglobulin G (IgG) proteins has been performed. Briefly, specific antibodies are immobilized onto nanorods, then IgG proteins are concentrated and captured, and finally, the signal from fluorescence-labelled antibodies are detected. The limit of detection (LoD) is measured as 275.3 fg/mL (~1.8 fM), which is a 20,000-fold enhancement compared with identical assays performed on blank glass plates. Further, prostate-specific antigen (PSA), which is a cancer biomarker for diagnosis of prostate cancer after radical prostatectomy, is also quantified with a LoD as low as 2.6 pg/mL. The time to signal saturation has been significantly reduced to one minute. In summary, together with an easy nanorod fabrication and integration method, this nanorods based DEP platform has demonstrated highly sensitive immunoassay performance and thus poses great potentials in applications for early point-of-care diagnostics.

Keywords: dielectrophoresis, immunoassay, oblique angle deposition, protein concentration

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Authors: Abdulqader Alkhouzaam, Hazim Qiblawey, Majeda Khraisheh

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Membrane treatment for desalination and wastewater treatment is one of the promising solutions to affordable clean water. It is a developing technology throughout the world and considered as the most effective and economical method available. However, the limitations of membranes’ mechanical and chemical properties restrict their industrial applications. Hence, developing novel membranes was the focus of most studies in the water treatment and desalination sector to find new materials that can improve the separation efficiency while reducing membrane fouling, which is the most important challenge in this field. Graphene oxide (GO) is one of the materials that have been recently investigated in the membrane water treatment sector. In this work, ultrafiltration polysulfone (PSF) membranes with high antifouling properties were synthesized by incorporating different loadings of GO. High-oxidation degree GO had been synthesized using a modified Hummers' method. The synthesized GO was characterized using different analytical techniques including elemental analysis, Fourier transform infrared spectroscopy - universal attenuated total reflectance sensor (FTIR-UATR), Raman spectroscopy, and CHNSO elemental analysis. CHNSO analysis showed a high oxidation degree of GO represented by its oxygen content (50 wt.%). Then, ultrafiltration PSF membranes incorporating GO were fabricated using the phase inversion technique. The prepared membranes were characterized using scanning electron microscopy (SEM) and atomic force microscopy (AFM) and showed a clear effect of GO on PSF physical structure and morphology. The water contact angle of the membranes was measured and showed better hydrophilicity of GO membranes compared to pure PSF caused by the hydrophilic nature of GO. Separation properties of the prepared membranes were investigated using a cross-flow membrane system. Antifouling properties were studied using bovine serum albumin (BSA) and humic acid (HA) as model foulants. It has been found that GO-based membranes exhibit higher antifouling properties compared to pure PSF. When using BSA, the flux recovery ratio (FRR %) increased from 65.4 ± 0.9 % for pure PSF to 84.0 ± 1.0 % with a loading of 0.05 wt.% GO in PSF. When using HA as model foulant, FRR increased from 87.8 ± 0.6 % to 93.1 ± 1.1 % with 0.02 wt.% of GO in PSF. The pure water permeability (PWP) decreased with loadings of GO from 181.7 L.m⁻².h⁻¹.bar⁻¹ of pure PSF to 181.1, and 157.6 L.m⁻².h⁻¹.bar⁻¹ with 0.02 and 0.05 wt.% GO respectively. It can be concluded from the obtained results that incorporating low loading of GO could enhance the antifouling properties of PSF hence improving its lifetime and reuse.

Keywords: antifouling properties, GO based membranes, hydrophilicity, polysulfone, ultrafiltration

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Authors: Ibrahim Khalil Ibrahim, Enas Mohamed Shahine, Abeer Shawky El Hadedy, Emmanuel Kamal Aziz Saba, Ghada Salah Attia Hussein

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Osteoarthritis (OA) is a multifactorial disease characterized by a progressive degradation of articular cartilage and is the leading cause of disability in elderly persons. IL-18 contributes to the destruction of cartilage and bone in the disease process of arthritis. The aim of the study was to investigate the role of IL-18 in primary knee OA patients. Serum level of IL-18 was assessed by enzyme-linked immunosorbent assay in 30 primary knee OA patients and compared to 20 age and gender-matched healthy volunteers as a control group. Radiographic severity of OA was assessed by Kellgren and Lawrence (KL) global scale. Pain, stiffness and functional assessment were done using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). OA patients had significantly higher serum IL-18 level than in control group (420.93 ± 345.4 versus 151.03 ± 144.16 pg/ml, P=0.001). Serum level of IL-18 was positively correlated with KL global scale (P=0.001). There were no statistically significant correlations between serum level of IL-18 and pain, stiffness, function subscales and total WOMAC index scores among the studied patients. In conclusions, IL-18 has a role in the pathogenesis of OA and it is positively correlated with the radiographic damage of OA.

Keywords: Interlukin-18, knee osteoarthritis, primary osteoarthritis, WOMAC scale

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Authors: Wedad Azhar

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Vitamin D is an essential fat-soluble vitamin that is required for the maintenance of good health. It is obtained either through exposure to sunlight (ultraviolet B radiation) or through dietary sources. The role of vitamin D is beyond bone health. Indeed, it plays a critical role in the immune system and a broad range of organ functions such as the cardiovascular system. Moreover, vitamin D plays a critical role in the endothelial function, which is one of the main indicators of atherosclerosis. This study is investigating the correlation between vitamin D status and endothelial function in preventing and treating atherosclerosis especially in country that has ample of sunshine but yet, Saudis from suffering from this issue vitamin D deficiency and insufficiency. Ninety participants from both genders and aged 40 to 60will be involved. The participants will be categorised into three groups: the control group will be healthy persons, patients at risk of developing atherosclerosis, patients formally diagnosed atherosclerosis. Half of the participants in each group should already have been taking vitamin D supplementations. Fasting blood samples will be taken from the participants for biochemical assays. Endothelial function will be assist by flow-mediated dilation of the brachial artery. Participants will be asked to complete a questionnaire on their social and economic status, education level, daily exposure to sunlight, smoking status, consumption of supplements and medication, and a food frequency of vitamin D intake. The data will be analysed using SPSS.

Keywords: atherosclerosis, endothelial function, nutrition, vitamin D

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Authors: Raman Kumar, Jasgurpreet Singh Chohan, Chander Shekhar Verma

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Today, the manufacturing industries respond rapidly to new demands and compete in this continuously changing environment, thus seeking out new methods allowing them to remain competitive and flexible simultaneously. The aim of the manufacturing organizations is to reduce manufacturing costs and wastes through system simplification, organizational potential, and proper infrastructural planning by using modern techniques like lean manufacturing. In India, large number of medium and large scale manufacturing industries has successfully implemented lean manufacturing techniques. Keeping in view the above-mentioned facts, different tools will be involved in the successful implementation of the lean approach. The present work is focused on the auto part manufacturing industry to improve the performance of the recliner assembly line. There is a number of lean manufacturing tools available, but the experience and complete knowledge of manufacturing processes are required to select an appropriate tool for a specific process. Fishbone diagrams (scrap, inventory, and waiting) have been drawn to identify the root cause of different. Effect of cycle time reduction on scrap and inventory is analyzed thoroughly in the case company. Results have shown that there is a decrease in inventory cost by 7 percent after the successful implementation of the lean tool.

Keywords: lean tool, fish-bone diagram, cycle time reduction, case study

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Authors: Zhengkun Yi

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Surface texture discrimination using artificial tactile sensors has attracted increasing attentions in the past decade as it can endow technical and robot systems with a key missing ability. However, as a major component of texture, roughness has rarely been explored. This paper presents an approach for tactile surface roughness discrimination, which includes two parts: (1) design and fabrication of a bioinspired artificial fingertip, and (2) tactile signal processing for tactile surface roughness discrimination. The bioinspired fingertip is comprised of two polydimethylsiloxane (PDMS) layers, a polymethyl methacrylate (PMMA) bar, and two perpendicular polyvinylidene difluoride (PVDF) film sensors. This artificial fingertip mimics human fingertips in three aspects: (1) Elastic properties of epidermis and dermis in human skin are replicated by the two PDMS layers with different stiffness, (2) The PMMA bar serves the role analogous to that of a bone, and (3) PVDF film sensors emulate Meissner’s corpuscles in terms of both location and response to the vibratory stimuli. Various extracted features and classification algorithms including support vector machines (SVM) and k-nearest neighbors (kNN) are examined for tactile surface roughness discrimination. Eight standard rough surfaces with roughness values (Ra) of 50 μm, 25 μm, 12.5 μm, 6.3 μm 3.2 μm, 1.6 μm, 0.8 μm, and 0.4 μm are explored. The highest classification accuracy of (82.6 ± 10.8) % can be achieved using solely one PVDF film sensor with kNN (k = 9) classifier and the standard deviation feature.

Keywords: bioinspired fingertip, classifier, feature extraction, roughness discrimination

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Authors: Farid Risheq, M. Zaid Alrisheq, Shuaa Al-Sadoon, Karim Al-Faqih, Mays Abdulazeez

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Breast cancer is the most frequently diagnosed cancer worldwide, and a common cause of death among women. Various conventional anatomical imaging tools are utilized for diagnosis, histological assessment and TNM (Tumor, Node, Metastases) staging of breast cancer. Biopsy of sentinel lymph node is becoming an alternative to the axillary lymph node dissection. Advances in 18-Fluoro-Deoxi-Glucose Positron Emission Tomography/Computed Tomography (18FDG-PET/CT) imaging have facilitated breast cancer diagnosis utilizing biological trapping of 18FDG inside lesion cells, expressed as Standardized Uptake Value (SUVmax). Objective: To present the utility of 18FDG uptake PET/CT scans in detecting active extra lymph nodes and distant occult metastases for breast cancer staging. Subjects and Methods: Four female patients were presented with initially classified TNM stages of breast cancer based on conventional anatomical diagnostic techniques. 18FDG-PET/CT scans were performed one hour post 18FDG intra-venous injection of (300-370) MBq, and (7-8) bed/130sec. Transverse, sagittal, and coronal views; fused PET/CT and MIP modality were reconstructed for each patient. Results: A total of twenty four lesions in breast, extended lesions to lung, liver, bone and active extra lymph nodes were detected among patients. The initial TNM stage was significantly changed post 18FDG-PET/CT scan for each patient, as follows: Patient-1: Initial TNM-stage: T1N1M0-(stage I). Finding: Two lesions in right breast (3.2cm2, SUVmax=10.2), (1.8cm2, SUVmax=6.7), associated with metastases to two right axillary lymph nodes. Final TNM-stage: T1N2M0-(stage II). Patient-2: Initial TNM-stage: T2N2M0-(stage III). Finding: Right breast lesion (6.1cm2, SUVmax=15.2), associated with metastases to right internal mammary lymph node, two right axillary lymph nodes, and sclerotic lesions in right scapula. Final TNM-stage: T2N3M1-(stage IV). Patient-3: Initial TNM-stage: T2N0M1-(stage III). Finding: Left breast lesion (11.1cm2, SUVmax=18.8), associated with metastases to two lymph nodes in left hilum, and three lesions in both lungs. Final TNM-stage: T2N2M1-(stage IV). Patient-4: Initial TNM-stage: T4N1M1-(stage III). Finding: Four lesions in upper outer quadrant area of right breast (largest: 12.7cm2, SUVmax=18.6), in addition to one lesion in left breast (4.8cm2, SUVmax=7.1), associated with metastases to multiple lesions in liver (largest: 11.4cm2, SUV=8.0), and two bony-lytic lesions in left scapula and cervicle-1. No evidence of regional or distant lymph node involvement. Final TNM-stage: T4N0M2-(stage IV). Conclusions: Our results demonstrated that 18FDG-PET/CT scans had significantly changed the TNM stages of breast cancer patients. While the T factor was unchanged, N and M factors showed significant variations. A single session of PET/CT scan was effective in detecting active extra lymph nodes and distant occult metastases, which were not identified by conventional diagnostic techniques, and might advantageously replace bone scan, and contrast enhanced CT of chest, abdomen and pelvis. Applying 18FDG-PET/CT scan early in the investigation, might shorten diagnosis time, helps deciding adequate treatment protocol, and could improve patients’ quality of life and survival. Trapping of 18FDG in malignant lesion cells, after a PET/CT scan, increases the retention index (RI%) for a considerable time, which might help localize sentinel lymph node for biopsy using a hand held gamma probe detector. Future work is required to demonstrate its utility.

Keywords: axillary lymph nodes, breast cancer staging, fluorodeoxyglucose positron emission tomography/computed tomography, lymph nodes

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Authors: Melliti Rihab, Zaeid Sonia, Khechine Wiem, Daldoul Amira

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Introduction: Lung cancer is the leading cause of cancer death. Its incidence is increasing, and its prognosis remains pejorative. We present the clinical, pathological, and therapeutic characteristics of bronchopulmonary cancer (BPC) in Tunisia. Methods: Retrospective study including patients followed in the oncology department of the University Hospital of Monastir between April 2014 and December 2021 suffering from lung cancer. Results: These are 117 patients, including 86.3% men and 13.7% women (sex ratio 6.3). The average age was 64 years ± 9 (37-83), with 95.7% being over 50 years old. Patients were smokers in 82% of cases. The clinical signs were dominated by chest pain (27.5%) and dyspnea in 21.1% of cases. In 6 patients, an episode of COVID-19 infection revealed the diagnosis. Half of the patients had a PS between 0 and 1. Small cell lung cancer was present in 18 patients (15.4%). The majority of non small cell lung cancer was of the adenocarcinoma type (68.7%). The diagnosis was late (stage IV) in 62.4% of cases. BPC was metastatic to bone (52%), contralateral lung (25.9%), and brain (27.3%). Patients were oligometastatic in 26% of cases. Surgery and radiotherapy were performed respectively in 14.5% and 23.1% of cases. Three-quarters of the patients had had nutrition (75.2%). The ROS1 mutation was present in 1 patient. PDL-1 expression was >40% in 2 patients. Survival was mean eight months ± 7.4. Conclusion: Lung cancer is diagnosed at a late stage in Tunisia. The lack of molecular study for non-small cell PBC and the lack of marketing authorization for tyrosine kinase inhibitors in Tunisia make the management incomplete.

Keywords: SCLC, NCSLC, ROS1, PDL1

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Authors: So Youn Park, Yi Sle Lee, Ki Whan Hong, Chi Dae Kim

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The role of metabolism in the pathogenesis of osteoarthritis is an emerging field. Metabolic alterations may be a role in osteoarthritis (OA) pathogenesis, and these changes influence joint destruction via several cytokine. Especially, in OA patients, levels of IL-1β are elevated in the synovial fluid, synovial membrane, subchondral bone, and cartilage. The IL-1β is activated by NLRP3 inflammasomes, and NLRP3 inflammasomes are cytosolic complexes that drive the production of other inflammatory cytokines, including IL-1β. In this study, we examined that SIRT1 suppresses IL-1β through inhibiting NLRP3 inflammasomes and SIRT1 ameliorates osteoarthritis. OA fibroblasts were isolated from synovium of OA patients. IL-1β and NLRP3 were detected in synovium of OA patients by immunohistochemistry. Lipopolysaccharides (LPS) stimulated the expression of active IL-1β mRNA in OA fibroblasts and combination of LPS, and adenosine triphosphate increased more the expression of active IL-1β in OA fibroblasts. The level of IL-1β was measured by western blot and ELISA assay. NLRP3 inflammasomes complex were measured by western blot. SIRT1 did not inhibit expression of NLRP3 inflammasome. So caspase-1, apoptotic speck-like protein containing a caspase recruitment domain (ASC) and NLRP3 protein were expressed in OA fibroblasts. But SIRT1 suppressed activation of IL-1β by inhibiting activity of caspase-1 via NLRP3 inflammasome in OA fibroblasts under LPS plus ATP stimulation. These results suggest that SIRT1 is a modulator of NLRP3 inflammasomes in OA fibroblasts and ameliorate IL-1β, so expression of SIRT1 in OA fibroblast may be a potential strategy for OA inflammation treatment.

Keywords: osteoarthritis, inflammasome, SIRT1, IL-1beta

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Authors: Tahir Mehmood, Mumtaz Akhter

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The global need for conflict management is greater now in the early 21st century than ever before. According to UNESCO, half of the world’s 195 countries will have to expand their stock of educationist significantly, some by tens of thousands, if the goal development targets are desired to achieve. Socioeconomic inequities, political instability, demographic changes and crises such as the HIV/AIDs epidemic have engendered huge shortfalls in teacher supply and low teacher quality in many developing countries. Education serves as back bone in development process. Open learning and distance education programs are serving as pivotal part of development process. It is now clear that ‘bricks and mortar’ approaches to expanding teacher education may not be adequate if the current and projected shortfalls in teacher supply and low teacher quality are to be properly addressed. The study is designed to measure the perceptions of teaching learning community about conflict management with special reference to open and distance learning. It was descriptive study which targeted teachers, students, community members and experts. Data analysis was carried out by using statistical techniques served by SPSS. Findings reflected that audience perceives open and distance learning as change agent and as development tool. It is noticed that target audience has driven prominent performance by using facility of open and distance learning.

Keywords: conflict management, open and distance learning, teachers, students

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Authors: Hosamuddin Hamza

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The major concept of 4D printing is self-folding under thermal and humidity changes. This concept relies on understanding how the microstructures of 3D-printed models can undergo spontaneous shape transformation under thermal and moisture changes. The transformation mechanism could be achieved by mixing, in a controllable pattern, a number of materials within the printed model, each with known strain/shrinkage properties. 4D printing has a strong potential to be applied in dentistry as the technology could produce dynamic and adaptable materials to be used as functional objects in the oral environment under the continuously changing thermal and humidity conditions. The motion criteria could override the undesired dimensional changes, thermal instability, polymerization shrinkage and microleakage. 4D printing could produce restorative materials being self-adjusted spontaneously without further intervention from the dentist or patient; that is, the materials could be capable of fixing its failed portions, compensating for some lost tooth structure, while avoiding microleakage or overhangs at the margins. In prosthetic dentistry, 4D printing could provide an option to manage the influence of bone and soft tissue imbalance during mastication (and at rest) with high predictability of the type/direction of forces. It can also produce materials with better fitting and retention characteristics than conventional or 3D-printed materials. Nevertheless, it is important to highlight that 4D-printed objects, having dynamic properties, could provide some cushion as they undergo self-folding compensating for any thermal changes or mechanical forces such as traumatic forces.

Keywords: functional material, self-folding material, 3D printing, 4D printing

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Authors: Brian Chi Yan Cheng, Hui Guo, Tao Su, Xiu‐qiong Fu, Ting Li, Zhi‐ling Yu

Abstract:

Rheumatoid arthritis (RA) affects around 1% of the globe population. Yet, there is still no cure for RA. Toll-like receptor 4 (TLR4) signalling has been found to be involved in the pathogenesis of RA, making it a potential therapeutic target for RA treatment. A herbal formula (RL) consisting of fruits of Rosa Multiflora (Eijitsu rose) and flowers of Lonicera Japonica (Japanese honeysuckle) has been used in treating various inflammatory disorders for more than a thousand year. Both of them are rich sources of nutrients and bioactive phytochemicals, which can be used in producing different food products and supplements. In this study, we would evaluate the anti-arthritic effect of RL on collagen-induced arthritis (CIA) in rats and investigate the involvement of TLR4 signaling in the mode of action of RL. Anti-arthritic efficacy was evaluated using CIA rats induced by bovine type II collagen. The treatment groups were treated with RL (82.5, 165, and 330 mg/kg bw per day, p.o.) or positive control indomethacin (0.25 mg/kg bw per day, p.o.) for 35 days. Clinical signs (hind paw volume and arthritis severity scores), changes in serum inflammatory mediators, pro-/antioxidant status, histological and radiographic changes of joints were investigated. Spleens and peritoneal macrophages were used to determine the effects of RL on innate and adaptive immune responses in CIA rats. The involvement of TLR4 signalling pathways in the anti-arthritic effect of RL was examined in cartilage tissue of CIA rats, murine RAW264.7 macrophages and human THP-1 monocytic cells. The severity of arthritis in the CIA rats was significantly attenuated by RL. Antioxidant status, histological score and radiographic score were efficiently improved by RL. RL could also dose-dependently inhibit pro-inflammatory cytokines in serum of CIA rats. RL significantly inhibited the production of various pro-inflammatory mediators, the expression and/or activity of the components of TLR4 signalling pathways in animal tissue and cell lines. RL possesses anti-arthritic effect on collagen-induced arthritis in rats. The therapeutic effect of RL may be related to its inhibition on pro-inflammatory cytokines in serum. The inhibition of the TAK1/NF-κB and TAK1/MAPK pathways participate in the anti-arthritic effects of RL. This provides a pharmacological justification for the dietary use of RL in the control of various arthritic diseases. Further investigation should be done to develop RL into a anti-arthritic food products and/or supplements.

Keywords: japanese honeysuckle, rheumatoid arthritis, rosa multiflora, rosehip

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Authors: S. Hallal, Z. Chami, A. Hadji-Lehtihet, S. Sokhal-Boudella, A. Berhoune, L. Yargui

Abstract:

Gaucher disease is the most common lysosomal storage in our population, it is due to a deficiency of β –glucosidase acid. The enzyme deficiency causes a pathological accumulation of undegraded substrate in lysosomes. This metabolic overload is responsible for a multisystemic disease with hepatosplenomegaly, anemia, thrombocytopenia, and bone involvement. Neurological involvement is rare. The laboratory diagnosis of Gaucher disease consists of phenotypic diagnosis by determining the enzymatic activity of β - glucosidase by fluorimetric method, a study by genotypic diagnosis in the GBA gene, limiting the search recurrent mutations (N370S, L444P, 84 GG); PCR followed by an enzymatic digestion. Abnormal profiles were verified by sequencing. Monitoring of treated patients is provided by the determination of chitotriosidase. Our experience spaning a period of 6 years (2007-2014) has enabled us to diagnose 78 patients out of a total of 328 requests from the various departments of pediatrics, internal medicine, neurology. Genotypic diagnosis focused on the entire family of 9 children treated at pediatric CHU Mustapha, which help define the clinical form; or 5 of them had type III disease, carrying the L444P mutation in the homozygous state. Three others were composite (N370/L444P) (N370S/other unintended mutation in our study), and only in one family no recurrent mutation has been found. This molecular study permits screening of heterozygous essential for genetic counseling.

Keywords: Gaucher disease, mutations, N370S, L444P

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Authors: Michael Stevens

Abstract:

David Hunter, a musicologist, has suggested that both Beethoven and Handel had chronic lead poisoning from the wine that they drank. These two eminent musical composers had some striking similarities. Beethoven had alcohol dependency and preferred wine, to which lead had been added to improve the taste. Handel was obese due to an eating disorder that included drinking tainted wine after large meals. They both had paresthesia of their extremities that they interpreted as rheumatism. This is a common sensory symptom from chronic lead poisoning. Their differences are marked in that Beethoven was profoundly deaf by the end of his life, whereas Handel had remarkably good hearing. Handel had paresis of three fingers of his right hand, whereas Beethoven lacked any motor symptoms. Beethoven reported recurrent abdominal pain suggestive of lead colic, whereas it can only be inferred that this symptom was present in Handel. Lead poisoning is likely in Handel because his paralysis was consistent with radial nerve involvement in the dominant hand. In addition, it was cured by hot baths, which have been shown to reduce total body lead content by exchanging with iron and calcium ions in water. Although lead produces predominantly motor symptoms in classic or subacute lead poisoning, and sensory symptoms in chronic lead poisoning, lead poisoning causes a variety of symptoms that depending on duration and level of exposure, are extremely variable from person to person. It therefore seems likely that Handel had lead poisoning, but extremely likely that Beethoven did because of the confirmatory finding of high levels of lead deep in his skull bone, which is a good measure of total body burden.

Keywords: beethoven, handel, lead, poisoning

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Authors: L. Siva Rama Krishna, Sriram Venkatesh, M. Sastish Kumar, M. Uma Maheswara Chary

Abstract:

Rapid Prototyping (RP) is a technology that produces models and prototype parts from 3D CAD model data, CT/MRI scan data, and model data created from 3D object digitizing systems. There are several RP process like Stereolithography (SLA), Solid Ground Curing (SGC), Selective Laser Sintering (SLS), Fused Deposition Modelling (FDM), 3D Printing (3DP) among them SLS and FDM RP processes are used to fabricate pattern of custom cranial implant. RP technology is useful in engineering and biomedical application. This is helpful in engineering for product design, tooling and manufacture etc. RP biomedical applications are design and development of medical devices, instruments, prosthetics and implantation; it is also helpful in planning complex surgical operation. The traditional approach limits the full appreciation of various bony structure movements and therefore the custom implants produced are difficult to measure the anatomy of parts and analyse the changes in facial appearances accurately. Cranioplasty surgery is a surgical correction of a defect in cranial bone by implanting a metal or plastic replacement to restore the missing part. This paper aims to do a comparative study on the dimensional error of CAD and SLS RP Models for reconstruction of cranial defect by comparing the virtual CAD with the physical RP model of a cranial defect.

Keywords: rapid prototyping, selective laser sintering, cranial defect, dimensional error

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Authors: Isabel Moscol, Carlos J. Díaz, Ciro Rodríguez

Abstract:

Hip replacement becomes necessary when a person suffers severe pain or considerable functional limitations and the best option to enhance their quality of life is through the replacement of the damaged joint. One of the main components in femoral prostheses is the stem which distributes the loads from the joint to the proximal femur. To preserve more bone stock and avoid weakening of the diaphysis, a short starting stem was selected, generated from the intramedullary morphology of the patient's femur. It ensures the implantability of the design and leads to geometric delimitation for personalized optimization with machine learning (ML) and metaheuristic algorithms. The present study attempts to design a cementless short stem to make the strain deviation before and after implantation close to zero, promoting its fixation and durability. Regression models developed to estimate the percentage change of maximum principal stresses were used as objective optimization functions by the metaheuristic algorithm. The latter evaluated different geometries of the short stem with the modification of certain parameters in oblique sections from the osteotomy plane. The optimized geometry reached a global stress shielding (SS) of 18.37% with a determination factor (R²) of 0.667. The predicted results favour implantability integration in the short stem optimization to effectively reduce SS in the proximal femur.

Keywords: machine learning techniques, metaheuristic algorithms, short-stem design, stress shielding, hip replacement

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Authors: Rima Zakzouk, Yasushi Shimada, Yasunori Sumi, Junji Tagami

Abstract:

Background and purpose: The resin composite has become the main material for the restorations of caries in recent years due to aesthetic characteristics, especially with the development of the adhesive techniques. The quality of adhesion to tooth structures is depending on an exchange process between inorganic tooth material and synthetic resin and a micromechanical retention promoted by resin infiltration in partially demineralized dentin. Optical coherence tomography (OCT) is a noninvasive diagnostic method for obtaining cross-sectional images that produce high-resolution of the biological tissue at the micron scale. The aim of this study was to evaluate the gap formation at adhesive/tooth interface of two-step self-etch adhesives that are preceded with or without phosphoric acid pre-etching in different regions of teeth using SS-OCT. Materials and methods: Round tapered cavities (2×2 mm) were prepared in cervical part of bovine incisors teeth and divided into 2 groups (n=10): first group self-etch adhesive (Clearfil SE Bond) was applied for SE group and second group treated with acid etching before applying the self-etch adhesive for PA group. Subsequently, both groups were restored with Estelite Flow Quick Flowable Composite Resin and observed under OCT. Following 5000 thermal cycles, the same section was obtained again for each cavity using OCT at 1310-nm wavelength. Scanning was repeated after two months to monitor the gap progress. Then the gap length was measured using image analysis software, and the statistics analysis were done between both groups using SPSS software. After that, the cavities were sectioned and observed under Confocal Laser Scanning Microscope (CLSM) to confirm the result of OCT. Results: Gaps formed at the bottom of the cavity was longer than the gap formed at the margin and dento-enamel junction in both groups. On the other hand, pre-etching treatment led to damage the DEJ regions creating longer gap. After 2 months the results showed almost progress in the gap length significantly at the bottom regions in both groups. In conclusions, phosphoric acid etching treatment did not reduce the gap lrngth in most regions of the cavity. Significance: The bottom region of tooth was more exposed to gap formation than margin and DEJ regions, The DEJ damaged with phosphoric acid treatment.

Keywords: optical coherence tomography, self-etch adhesives, bottom, dento enamel junction

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Authors: Hsin-Lien Lin, Ju-Hui Fu

Abstract:

Dendritic cells (DCs) are the major professional antigen-presenting cells for the development of optimal T-cell immunity. DCs can be used as pharmacological targets to screen novel biological modifiers for the treatment of harmful immune responses, such as transplantation rejection. Dryopteris crassirhizoma Nakai (Aspiadaceae) is used for traditional herbal medicine in the region of East Asia. The root of this fern plant has been listed for treating inflammatory diseases. Dryocrassin is the tetrameric phlorophenone component derived from Dryopteris. Here, we tested the immunomodulatory potential of dryocrassin on lipopolysaccharide (LPS)-stimulated activation of mouse bone marrow-derived DCs in vitro and in skin allograft transplantation in vivo. Results demonstrated that dryocrassin reduced the secretion of tumor necrosis factor-α, interleukin-6, and interleukin-12p70 by LPS-stimulated DCs. The expression of LPS-induced major histocompatibility complex class II, CD40, and CD86 on DCs was also blocked by dryocrassin. Moreover, LPS-stimulated DC-elicited allogeneic T-cell proliferation was lessened by dryocrassin. In addition, dryocrassin inhibited LPS-induced activation of IϰB kinase, JNK/p38 mitogen-activated protein kinase, as well as the translocation of NF-ϰB. Treatment with dryocrassin obviously diminished 2,4-dinitro-1-fluorobenzene- induced delayed-type hypersensitivity and prolonged skin allograft survival. Dryocrassin may be one of the potent immunosuppressive agents for transplant rejection through the destruction of DC maturation and function.

Keywords: dryocrassin, dendritic cells, immunosuppression, skin allograft

Procedia PDF Downloads 386

Authors: Ayat E. Ali, Christeen R. Aziz, Merna A. Helmy, Mohammed M. Malek, Sherif H. El-Gohary

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Goal: Purpose of the project was to make a plastic surgery prediction by using pre-operative images for the plastic surgeries’ patients and to show this prediction on a screen to compare between the current case and the appearance after the surgery. Methods: To this aim, we implemented a software which used data from the internet for facial skin diseases, skin burns, pre-and post-images for plastic surgeries then the post- surgical prediction is done by using K-nearest neighbor (KNN). So we designed and fabricated a smart mirror divided into two parts a screen and a reflective mirror so patient's pre- and post-appearance will be showed at the same time. Results: We worked on some skin diseases like vitiligo, skin burns and wrinkles. We classified the three degrees of burns using KNN classifier with accuracy 60%. We also succeeded in segmenting the area of vitiligo. Our future work will include working on more skin diseases, classify them and give a prediction for the look after the surgery. Also we will go deeper into facial deformities and plastic surgeries like nose reshaping and face slim down. Conclusion: Our project will give a prediction relates strongly to the real look after surgery and decrease different diagnoses among doctors. Significance: The mirror may have broad societal appeal as it will make the distance between patient's satisfaction and the medical standards smaller.

Keywords: k-nearest neighbor (knn), face detection, vitiligo, bone deformity

Procedia PDF Downloads 163

Authors: Ping-Lun Jiang, Hung-Jun Lin, Shen-Fu Lin, Mei-Yin Chien, Ting-Wei Li, Chun-Han Lin, Der-Zen Liu

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Mucosal vaccine induces both mucosal (secretory IgA) and systemic immune responses and it is considered an ideal vaccination strategy for prevention of infectious diseases. One important point to be considered in mucosal vaccination is effective antigen delivery system which can manage effective delivery of antigen to antigen-presenting cells (APCs) of mucosal. In the present study, cationic gelatin nanoparticles were prepared as ideal carriers for more efficient antigen delivery. The average diameter of cationic gelatin nanoparticle was approximate 190 nm, and the zeta potential was about +45 mV, then ovalbumin (OVA) was physically absorbed onto cationic gelatin nanoparticle. The OVA absorption rate was near 95% the zeta potential was about +20 mV. We show that cationic gelatin nanoparticle effectively facilitated antigen uptake by mice bone marrow-derived dendritic cells (mBMDCs) and RAW264.7 cells and induced higher levels of pro-inflammatory cytokines. C57BL/6 mice twice immunized intranasally with OVA-absorbed cationic gelatin nanoparticle induced high levels of OVA-specific IgG in the serum and IgA in their in the nasal and lung wash fluid. These results indicate that nasal administration of cationic gelatin nanoparticles induced both mucosal and systemic immune responses and cationic gelatin nanoparticles might be a potential antigen delivery carrier for further clinical applications.

Keywords: antigen delivery, antigen-presenting cells, gelatin nanoparticle, mucosal vaccine

Procedia PDF Downloads 359

Authors: Suteera Pradubwong, Darawan Augsornwan, Pornpen Pathumwiwathana, Benjamas Prathanee, Bowornsilp Chowchuen

Abstract:

Background: Cleft lip and palate (CLP) congenital anomalies have a high prevalence in the Northeast of Thailand. A care team’s understand of treatment plan would help to guide the family of patients with CLP to achieve the treatment. Objectives: To examine the impact of the empowering volunteer project, established in the northeast Thailand. Materials and Methods: The Empowering Volunteer project was conducted in 2008 under the Tawanchai Royal Granted project. The patients and family’s general information, treatment, the group brainstorming, and satisfaction with the project were analyzed. Results: Participants were 12 children with CLP, their families and five volunteers with CLP; the participating patients were predominantly females and the mean, age was 12.2 years. The treatment comprised of speech training, dental hygiene care, bone graft and orthodontic treatment. Four issues were addressed including: problems in taking care of breast feeding; instructions’ needs for care at birth; difficulty in access information and society impact; and needs in having a network of volunteers. Conclusions: Empowering volunteer is important for holistic care of patients with CLP which provides easy access and multiple channels for patients and their families. It should be developed as part of the self-help and family support group, the development of community based team and comprehensive CLP care program.

Keywords: self-help and family support group, community based model, volunteer, cleft lip-cleft palate

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Authors: Roni Rachel Mendelson, Caileigh Pudela

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Bacillus cereus is a toxin-producing, facultatively anaerobic gram-positive bacterium that is widely distributed environmentally. It can quickly multiply at room temperature with an abundantly present preformed toxin. When ingested, this toxin can cause gastrointestinal illness, which is the commonly known manifestation of the disease. Bacillus cereus sepsis is a disease that is mostly concerning in the population of the immunocompromised patients. One of them is acute lymphoblastic leukemia’s patients during induction. Pediatric acute lymphoblastic leukemia is a common pediatric hematologic malignancy. It is characterized by the rapid proliferation of poorly differentiated lymphoid progenitor cells inside the bone marrow. We present here a 21-month-old boy undergoing induction chemotherapy for acute lymphoblastic leukemia who developed bacillus sepsis bacteremia and, as a result, multi organ failure leading to seizures and multiple strokes. Our case report highlights the extensive overall and neurological damage that can be caused because of bacillus cereus bacteremia, which can lead to higher mortality rate and decreased in survivorship in a highly curable disease. It is very subtle and difficult to recognize and appears to be deteriorating extremely fast. There should be a low threshold for work up and empiric coverage for neutropenic patients during acute lymphoblastic leukemia induction therapy.

Keywords: acute lymphoblastic leukemia, bacillus cereus, immunocompromised, sepsis

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Authors: Mohammad Khan, Arnaud Castel

Abstract:

Concrete viscoelastic properties such as shrinkage, creep, and associated relaxation are important in assessing the risk of cracking during the first few days after placement. This paper investigates the early-age mechanical and viscoelastic properties, restrained shrinkage-induced cracking and time to cracking of concrete incorporating ferronickel slag (FNS) as supplementary cementitious material. Compressive strength, indirect tensile strength and elastic modulus were measured. Tensile creep and drying shrinkage was measured on dog-bone shaped specimens. Restrained shrinkage induced stresses and concrete cracking age were assessed by using the ring test. Results revealed that early-age strength development of FNS blended concrete is lower than that of the corresponding ordinary Portland cement (OPC) concrete. FNS blended concrete showed significantly higher tensile creep. The risk of early-age cracking for the restrained specimens depends on the development of concrete tensile stress considering both restrained shrinkage and tensile creep and the development of the tensile strength. FNS blended concrete showed only 20% reduction in time to cracking compared to reference OPC concrete, and this reduction is significantly lower compared to fly ash and ground granulated blast furnace slag blended concretes at similar replacement level.

Keywords: ferronickel slag, restraint shrinkage, tensile creep, time to cracking

Procedia PDF Downloads 185