Search results for: MG63 cell line

Authors: Anika Pallapothu

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Periodontitis, a severe gum disease, poses a significant threat to the integrity of bone and soft tissues supporting teeth, primarily initiated by bacterial accumulation around the gum line. Conventional treatments like scaling/root planning and plaque removal are widely employed, but integrating modern technologies such as nanotechnology holds promise for innovative therapeutic approaches. This study explores the utilization of silver nanoparticles encapsulated within cellulose nanofiber (CNF) and mesoporous bioactive glass hydrogel matrices for periodontitis management. Silver nanoparticles exhibit potent antimicrobial properties by disrupting microbial cell membranes, inducing reactive oxygen species (ROS) generation, and interfering with vital cellular processes like ATP production and nucleic acid synthesis. Mesoporous bioactive glass, renowned for its high surface area, osteoconductive, and bioactivity, presents a favorable platform for pharmaceutical applications. Incorporating CNF enhances the properties of the hydrogel due to its biocompatibility, biodegradability, and water absorption capacity. The proposed composite material is anticipated to exert beneficial effects in periodontitis treatment by demonstrating antibacterial and anti-inflammatory activities, offering a promising avenue for future therapeutic interventions.

Keywords: periodontitis, cellulose nanofibers, silver nanoparticles, mesoporous bioactive glass, antibacterial activity, anti-inflammatory activity

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Authors: Hala M. El-hanbuli, Mohammed F. Darweesh

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The incidence rates of any tumor vary hugely with geographical location. Basal Cell Carcinoma (BCC) is one of the most common skin cancer that has many histopathologic subtypes. Objective: The aim was to study the histopathological features of BCC cases that were received in the Pathology Department, Kasr El-Aini hospital, Cairo University, Egypt during the period from Jan 2004 to Dec 2013 and to evaluate the clinical characters through the patient data available in the request sheets. Methods: Slides and data of BCC cases were collected from the archives of the pathology department, Kasr El-Aini hospital. Revision of all available slides and histological classification of BCC according to WHO (2006) was done. Results: A total number of 310 cases of BCC representing about 65% from the total number of malignant skin tumors examined during the 10-years duration in the department. The age ranged from 8 to 84 years, the mean age was (55.7 ± 15.5). Most of the patients (85%) were above the age of 40 years. There was a slight male predominance (55%). Ulcerated BCC was the most common gross picture (60%), followed by nodular lesion (30%) and finally the ulcerated nodule (10%). Most of the lesions situated in the high-risk sites (77%) where the nose was the most common site (35%) followed by the periocular area (22%), then periauricular (15%) and finally perioral (5%). No lesion was reported outside the head. The tumor size was less than 2 centimeters in 65% of cases, and from 2-5 centimeters in the lesions' greatest dimension in the rest of cases. Histopathological reclassification revealed that the nodular BCC was the most common (68%) followed by the pigmented nodular (18.75%). The histologic high-risk groups represented (7.5%) about half of them (3.75%) being basosquamous carcinoma. The total incidence for multiple BCC and 2nd primary was 12%. Recurrent BCC represented 8%. All of the recurrent lesions of BCC belonged to the histologic high-risk group. Conclusion: Basal Cell Carcinoma is the most common skin cancer in the 10-year survey. Histopathological diagnosis and classification of BCC cases are essential for the determination of the tumor type and its biological behavior.

Keywords: basal cell carcinoma, high risk, histopathological features, statistical analysis

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Authors: Özlem Ateş Sönmezoğlu, Begüm Terzi, Ahmet Yıldırım, Leyla Gündüz

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Durum wheat quality is defined as its suitability for pasta processing, that is pasta making quality. Another factor that determines the quality of durum wheat is the nutritional value of wheat or its final products. Wheat is a basic source of calories, proteins and minerals for humans in many countries of the world. For this reason, improvement of wheat nutritional value is of great importance. In recent years, deficiencies in protein and micronutrients, particularly in iron and zinc, have seriously increased. Therefore, basic foods such as wheat must be improved for micronutrient content. The effects of some major genes for grain quality established. Gpc-B1 locus is one of the genes increased protein and micronutrients content, and used in improvement studies of durum wheat nutritional value. The aim of this study was to increase the protein content and the micronutrient (Fe, Zn ve Mn) contents of an advanced durum wheat line (TMB 1) that was previously improved for its protein quality. For this purpose, TMB1 advanced durum wheat line were used as the recurrent parent and also, UC1113-Gpc-B1 line containing the Gpc-B1 gene was used as the gene source. In all of the generations, backcrossed plants carrying the targeted gene region were selected by marker assisted selection (MAS). BC4F1 plants MAS method was employed in combination with embryo culture and rapid plant growth in a controlled greenhouse conditions in order to shorten the duration of the transition between generations in backcross breeding. The Gpc-B1 gene was selected specific molecular markers. Since Yr-36 gene associated with Gpc-B1 allele, it was also transferred to the Gpc-B1 transferred lines. Thus, the backcrossed plants selected by MAS are resistance to yellow rust disease. This research has been financially supported by TÜBİTAK (112T910).

Keywords: Durum wheat, Gpc-B1, MAS, Triticum durum, Yr-36

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Authors: Behnaz Jamshidi, Seyed Hassan Hashemabadi

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The main objective of this study is to investigate on pigging operation of two phase flow pipeline and compare the empirical and simulation results for 108 km long , 0.7934 mm (32 inches) diameter sea line of "Phase 1 South Pars Gas Complex", located in south of Iran. The pigging time, pig velocity, the amount of slug and slug catcher pressure were calculated and monitored closely as the key parameters. Simulation was done by "OLGA" dynamic simulation software and obtained results were compared and validated with empirical data in real operation. The relative errors between empirical data and simulation of the process were 3 % and 9 % for pigging time and accumulated slug volume respectively. Simulated pig velocity and changes of slug catcher pressure were consistent with real values, too. It was also found the slug catcher and condensate stabilization units have been adequately sized for gas-liquid separation and handle the slug batch during transient conditions such as pigging and start up.

Keywords: sea line, pigging, slug catcher, two-phase flow, dynamic simulation

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Authors: Saiful Islam, Deuk Jong Bae

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The purpose of this study is to examine citizen satisfaction and competitiveness of a Public Private Partnership project. The study focuses on PPP in the transport sector and investigates the New Bundang Subway Line (NBL) in South Korea as the object of a case study. Most PPP studies are dominated by the study of public and private sector interests, which are classified in to three major areas comprising of policy, finance, and management. This study will explore the user perspective by assessing customer satisfaction upon NBL cost and service quality, also the competitiveness of NBL compared to other alternative transport modes which serve the Jeongja – Gangnam trip or vice versa. The regular Bundang Subway Line, New Bundang Subway Line, bus and private vehicle are selected as the alternative transport modes. The study analysed customer satisfaction of NBL and citizen’s preference of alternative transport modes based on a survey in Bundang district, South Korea. Respondents were residents and employees who live or work in Bundang city, and were divided into the following areas Pangyo, Jeongjae – Sunae, Migeun – Ori – Jukjeon, and Imae – Yatap – Songnam. The survey was conducted in January 2015 for two weeks, and 753 responses were gathered. By applying the Hedonic Utility approach, the factors which affect the frequency of using NBL were found to be overall customer satisfaction, convenience of access, and the socio economic demographic of the individual. In addition, by applying the Analytic Hierarchy Process (AHP) method, criteria factors influencing the decision to select alternative transport modes were identified. Those factors, along with the author judgement of alternative transport modes, and their associated criteria and sub-criteria produced a priority list of user preferences regarding their alternative transport mode options. The study found that overall the regular Bundang Subway Line (BL), which was built and operated under a conventional procurement method was selected as the most preferable transport mode due to its cost competitiveness. However, on the sub-criteria level analysis, the NBL has competitiveness on service quality, particularly on journey time. By conducting a sensitivity analysis, the NBL can become the first choice of transport by increasing the NBL’s degree of weight associated with cost by 0,05. This means the NBL would need to reduce either it’s fare cost or transfer fee, or combine those two cost components to reduce the total of the current cost by 25%. In addition, the competitiveness of NBL also could be obtained by increasing NBL convenience through escalating access convenience such as constructing an additional station or providing more access modes. Although these convenience improvements would require a few extra minutes of journey time, the user found this to be acceptable. The findings and policy suggestions can contribute to the next phase of NBL development, showing that consideration should be given to the citizen’s voice. The case study results also contribute to the literature of PPP projects specifically from a user side perspective.

Keywords: public private partnership, customer satisfaction, public transport, new Bundang subway line

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Authors: Zahraa Al Ali, Ammar Abulibdeh, Talal Al-Awadhi, Midhun Mohan, Mohammed Al-Barwani, Mohammed Al-Barwani, Sara Al Nabbi, Meshal Abdullah

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This study aims to evaluate the performance and effectiveness of six spectral water indices - derived from Multispectral sentinel-2 data - to detect soil moisture and inundated area in arid regions to be used as an indicator of mudflow phenomena to predict high-risk areas. Herein, the validation of the performance of spectral indices was conducted using threshold method, spectral curve performance, and soil-line method. These indirect validation techniques play a key role in saving time, effort, and cost, particularly for large-scale and inaccessible areas. It was observed that the Normalized Difference Water Index (NDWI), Modified Normalized Difference Water Index (mNDWI), and RSWIR indices have the potential to detect soil moisture and inundated areas in arid regions. According to the temporal spectral curve performance, the spectral characteristics of water and soil moisture were distinct in the Near infrared (NIR), Short-wave Infrared (SWIR1,2) bands. However, the rate and degree differed between these bands, depending on the amount of water in the soil. Furthermore, the soil line method supported the appropriate selection of threshold values to detect soil moisture. However, the threshold values varied with location, time, season, and between indices. We concluded that considering the factors influencing the behavior of water and soil reflectivity could support decision-makers in identifying high-risk mudflow locations.

Keywords: spectral reflectance curve, soil-line method, spectral indices, Shaheen cyclone

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Authors: Halima Albalushi, Mohadese Boroojerdi, Murtadha Alkhabori

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Introduction: Maintenance of stem cell properties during culture necessitates the recreation of the natural cell niche. Studies reported the promising outcome of mesenchymal stem cells (MSC) properties maintenance after using extracellular matrix such as CELLstart™, which is the recommended coating material for stem cells cultured in serum-free and xeno-free conditions. Laminin-521 is known as a crucial adhesion protein, which is found in natural stem cell niche, and plays an important role in facilitating the maintenance of self-renewal, pluripotency, standard morphology, and karyotype of human pluripotent stem cells (PSCs). The aim of this study is to investigate the effects of Laminin-521 on human umbilical cord-derived mesenchymal stem cells (UC-MSC) characteristics as a step toward clinical application. Methods: Human MSC were isolated from the umbilical cord via the explant method. Umbilical cord-derived-MSC were cultured in serum-free and xeno-free conditions in the presence of Laminin-521 for six passages. Cultured cells were evaluated by morphology and expansion index for each passage. Phenotypic characterization of UC-MSCs cultured on Laminin-521 was evaluated by assessment of cell surface markers. Results: Umbilical cord derived-MSCs formed small colonies and expanded as a homogeneous monolayer when cultured on Laminin-521. Umbilical cord derived-MSCs reached confluence after 4 days in culture. No statistically significant difference was detected in all passages when comparing the expansion index of UC-MSCs cultured on LN-521 and CELLstart™. Phenotypic characterization of UC-MSCs cultured on LN-521 using flow cytometry revealed positive expression of CD73, CD90, CD105 and negative expression of CD34, CD45, CD19, CD14 and HLA-DR.Conclusion: Laminin-521 is comparable to CELLstart™ in supporting UC-MSCs expansion and maintaining their characteristics during culture in xeno-free and serum-free culture conditions.

Keywords: mesenchymal stem cells, culture, laminin-521, xeno-free serum-free

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Authors: Sanjay Kumar Behera, Kanhu Charan Patra

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A GIS-based method has been applied for the determination of soil erosion and sediment yield in a small watershed in Ong River basin, Odisha, India. The method involves spatial disintegration of the catchment into homogenous grid cells to capture the catchment heterogeneity. The gross soil erosion in each cell was calculated using Universal Soil Loss Equation (USLE) by carefully determining its various parameters. The concept of sediment delivery ratio is used to route surface erosion from each of the discretized cells to the catchment outlet. The process of sediment delivery from grid cells to the catchment outlet is represented by the topographical characteristics of the cells. The effect of DEM resolution on sediment yield is analyzed using two different resolutions of DEM. The spatial discretization of the catchment and derivation of the physical parameters related to erosion in the cell are performed through GIS techniques.

Keywords: DEM, GIS, sediment delivery ratio, sediment yield, soil erosion

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Authors: Shima Fasahat

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This research is an experimental research which was done about microbial fuel cells in order to study them for electricity generating and wastewater treatment. These days, it is very important to find new, clean and sustainable ways for energy supplying. Because of this reason there are many researchers around the world who are studying about new and sustainable energies. There are different ways to produce these kind of energies like: solar cells, wind turbines, geothermal energy, fuel cells and many other ways. Fuel cells have different types one of these types is microbial fuel cell. In this research, an MFC was built in order to study how it can be used for electricity generating and wastewater treatment. The microbial fuel cell which was used in this research is a reactor that has two tanks with a catalyst solution. The chemical reaction in microbial fuel cells is a redox reaction. The microbial fuel cell in this research is a two chamber MFC. Anode chamber is an anaerobic one (ABR reactor) and the other chamber is a cathode chamber. Anode chamber consists of stabilized sludge which is the source of microorganisms that do redox reaction. The main microorganisms here are: Propionibacterium and Clostridium. The electrodes of anode chamber are graphite pages. Cathode chamber consists of graphite page electrodes and catalysts like: O₂, KMnO₄ and C₆N₆FeK₄. The membrane which separates the chambers is Nafion117. The reason of choosing this membrane is explained in the complete paper. The main goal of this research is to generate electricity and treating wastewater. It was found that when you use electron receptor compounds like: O_2, MnO₄, C₆N₆FeK₄ the velocity of electron receiving speeds up and in a less time more current will be achieved. It was found that the best compounds for this purpose are compounds which have iron in their chemical formula. It is also important to pay attention to the amount of nutrients which enters to bacteria chamber. By adding extra nutrients in some cases the result will be reverse.  By using ABR the amount of chemical oxidation demand reduces per day till it arrives to a stable amount.

Keywords: anaerobic baffled reactor, bioenergy, electrode, energy efficient, microbial fuel cell, renewable chemicals, sustainable

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Authors: Aditi Mittal, Nishit Gupta, Tina Dadu, Anil Handoo

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Introduction: Hematopoietic stem cell transplantation (HSCT) is a curative treatment done for hematologic malignancies and other clinical conditions. Its main objective is to reconstitute the hematopoietic system of the recipient by administering an infusion of donor hematopoietic stem cells. Transplant engraftment is the first sign of bone marrow recovery. The main objective of this study is to assess immature platelet fraction (IPF) and immature reticulocyte fraction (IRF) as early indicators of post-hematopoietic stem cell transplant engraftment. Methods: Patients of all age groups and both genders undergoing both autologous and allogeneic transplants were included in the study. All the CBC samples were run on Mindray CAL-8000 (BC-6800 plus; Shenzhen, China) analyser and assessed for IPF and IRF. Neutrophil engraftment was defined as the first of three consecutive days with an ANC >0.5 x 109/L and platelet engraftment with a count >20 x 109/L. The cut-off values for IRF were calculated as 13.5% with a CV of 5% and for IPF was 19% with a CV of 12%. Results: The study sample comprised 200 patients, of whom 116 had undergone autologous HSCT, and 84 had undergone allogeneic HSCT. We observed that IRF anticipated the neutrophil recovery by an average of 5 days prior to IPF. Though there was no significant variation in IPF and IRF for the prediction of platelet recovery, IRF was preceded by 1 or 2 days to IPF in 25% of cases. Conclusions: Both IPF and IRF can be used as reliable parameters as predictors for post-transplant engraftment; however, IRF seems to be more reliable than IPF as a simple, inexpensive, and widely available tool for predicting marrow recovery several days before engraftment.

Keywords: transplantation, stem cells, reticulocyte, engraftment

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Authors: Vishnu Varthan Vaithiyalingam Jagannathan, Lakshmi Karunanidhi Santhanalakshmi, Srividya Ammayappan Rajam

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Formononetin is the O-Methoxy Flavonol that has many pharmacological activities, which belongs to the flavonoid family. In the current study, activity of this molecule was evaluated in lung cancer cell lines. In general, flavonoids possess certain anticancer mechanism. Being a flavonoid subfamily, this molecule was subjected to evaluate cytotoxicity assay by MTT ((3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide)) stain, mode of cell death assay stained by acridine orange and ethidium bromide and Evaluation of Apoptosis pathway (extrinsic or intrinsic) by Caspase 3/7 stain and Rhodamine-123 stain. From the results, we could able to confirm that the investigatory molecule formononetin has anticancer activity and in future, the study will propose to evaluate the formononetin action against genetic changes occurs during lung cancer progression.

Keywords: Caspase 3/7, formononetin, lung cancer, Rhodamine-123

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Authors: Abdul Matin, Muhammad Ajmal, Uzma Yunus, Noaman-ul Haq, Hafiz M. Shohaib, Ambreen G. Muazzam

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Carbon nanoparticles (CNPs) have unique properties that are useful for the diagnosis and treatment of cancer due to their precise properties like small size (ideal for delivery within the body) stability in solvent and tunable surface chemistry for targeted delivery. Here, highly fluorescent, monodispersed and water-soluble CNPs were synthesized directly from a suitable carbohydrate source (glucose and sucrose) by one-step acid assisted ultrasonic treatment at 35 KHz for 4 hours. This method is green, simple, rapid and economical and can be used for large scale production and applications. The average particle sizes of CNPs are less than 10nm and they emit bright and colorful green-blue fluorescence under the irradiation of UV-light at 365nm. The CNPs were characterized by scanning electron microscopy, fluorescent spectrophotometry, Fourier transform infrared spectrophotometry, ultraviolet-visible spectrophotometry and TGA analysis. Fluorescent CNPs were used as fluorescent probe and nano-carriers for anticancer drug. Functionalized CNPs (with ethylene diamine) were attached with anticancer drug-Methotrexate. In vitro bioactivity and biocompatibility of CNPs-drug conjugates was evaluated by LDH assay and Sulforhodamine B assay using human lung carcinoma cell lines (H157). Our results reveled that CNPs showed biocompatibility and CNPs-anticancer drug conjugates have shown potent cytotoxic effects and high antitumor activities in lung cancer cell lines. CNPs are proved to be excellent substitute for conventional drug delivery cargo systems and anticancer therapeutics in vitro. Our future studies will be more focused on using the same nanoparticles in vivo model system.

Keywords: carbon nanoparticles, carbon nanoparticles-methotrexate conjugates, human lung carcinoma cell lines, lactate dehydrogenase, methotrexate

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Authors: Vinaya Kambappa, Chinnadurai Mani, Komaraiah Palle

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Non-small cell-lung cancer (NSCLC) cells have increased expression of EGFR, which makes them a potential target for cancer therapy. Based on molecular docking and previous reports, we designed and synthesized quinazoline derivatives as potent EGFR inhibitors. Among the derivatives, three compounds showed good antiproliferative activity against A-549 and H-1299 cells. Furthermore, these compounds inhibited EGFR signaling exhibiting diminishing p-EGFR and its downstream proteins like p-Akt, p-Erk1/2, and p-mTOR; however, it did not alter the levels of EGFR, Akt, Erk1/2 and mTOR proteins. Flow cytometric analysis indicated the accumulation of cells at G1 phase suggesting induction of apoptosis, which was further confirmed by annexin V/propidium iodide staining. Our study suggested that quinazoline scaffold can be developed as novel EGFR kinase inhibitors for cancer therapy.

Keywords: apoptosis, non-small cell-lung cancer cells, EGFR, quinazoline

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Authors: Arnab Sarkar, Michael Huang, Chuang Ren, Jun Li

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The increasing importance of computing in modern society has brought substantial growth in the demand for more computational power. In some problem domains such as scientific simulations, available computational power still sets a limit on what can be practically explored in computation. For many types of code, there is non-uniformity in the utility of computation. That is not every piece of computation contributes equally to the quality of the result. If this non-uniformity is understood well and exploited effectively, we can much more effectively utilize available computing power. In this paper, we discuss a case study of exploring such non-uniformity in a particle-in-cell simulation platform. We find both the existence of significant non-uniformity and that it is generally straightforward to exploit it. We show the potential of order-of-magnitude effective performance gain while keeping the comparable quality of output. We also discuss some challenges in both the practical application of the idea and evaluation of its impact.

Keywords: approximate computing, landau damping, non uniform utility computing, particle-in-cell

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Authors: Natalie Riley, Anita Quigley, Robert M. I. Kapsa, George W. Greene

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As the fields of medicine and bionics grow rapidly in technological advancement, the future and success of it depends on the ability to effectively interface between the artificial and the biological worlds. The biggest obstacle when it comes to implantable, electronic medical devices, is maintaining a ‘clean’, low noise electrical connection that allows for efficient sharing of electrical information between the artificial and biological systems. Implant fouling occurs with the adhesion and accumulation of proteins and various cell types as a result of the immune response to protect itself from the foreign object, essentially forming an electrical insulation barrier that often leads to implant failure over time. Lubricin (LUB) functions as a major boundary lubricant in articular joints, a unique glycoprotein with impressive anti-adhesive properties that self-assembles to virtually any substrate to form a highly ordered, ‘telechelic’ polymer brush. LUB does not passivate electroactive surfaces which makes it ideal, along with its innate biocompatibility, as a coating for implantable bionic electrodes. It is the aim of the study to investigate LUB’s anti-fouling properties and its potential as a safe, bioinspired material for coating applications to enhance the performance and longevity of implantable medical devices as well as reducing the frequency of implant replacement surgeries. Native, bovine-derived LUB (N-LUB) and recombinant LUB (R-LUB) were applied to gold-coated mylar surfaces. Fibroblast, chondrocyte and neural cell types were cultured and grown on the coatings under both passive and electrically stimulated conditions to test the stability and anti-adhesive property of the LUB coating in the presence of an electric field. Lactate dehydrogenase (LDH) assays were conducted as a directly proportional cell population count on each surface along with immunofluorescent microscopy to visualize cells. One-way analysis of variance (ANOVA) with post-hoc Tukey’s test was used to test for statistical significance. Under both passive and electrically stimulated conditions, LUB significantly reduced cell attachment compared to bare gold. Comparing the two coating types, R-LUB reduced cell attachment significantly compared to its native counterpart. Immunofluorescent micrographs visually confirmed LUB’s antiadhesive property, R-LUB consistently demonstrating significantly less attached cells for both fibroblasts and chondrocytes. Preliminary results investigating neural cells have so far demonstrated that R-LUB has little effect on reducing neural cell attachment; the study is ongoing. Recombinant LUB coatings demonstrated impressive anti-adhesive properties, reducing cell attachment in fibroblasts and chondrocytes. These findings and the availability of recombinant LUB brings into question the results of previous experiments conducted using native-derived LUB, its potential not adequately represented nor realized due to unknown factors and impurities that warrant further study. R-LUB is stable and maintains its anti-fouling property under electrical stimulation, making it suitable for electroactive surfaces.

Keywords: anti-fouling, bioinspired, cell attachment, lubricin

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Authors: Tomás Sobrino, Lara García-Varela, Marta Aramburu-Núñez, Mónica Castro, Noemí Gómez-Lado, Mariña Rodríguez-Arrizabalaga, Antía Custodia, Juan Manuel Pías-Peleteiro, José Manuel Aldrey, Daniel Romaus-Sanjurjo, Ángeles Almeida, Pablo Aguiar, Alberto Ouro

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Introduction: Alzheimer’s disease (AD) and other tauopathies are primary causes of dementia, causing progressive cognitive deterioration that entails serious repercussions for the patients' performance of daily tasks. Currently, there is no effective approach for the early diagnosis and treatment of AD and tauopathies. This study suggests a theragnostic approach based on the importance of phosphorylated tau protein (p-Tau) in the early pathophysiological processes of AD. We have developed a novel theragnostic monoclonal antibody (mAb) to provide both diagnostic and therapeutic effects. Methods/Results: We have developed a p-Tau mAb, which was doped with deferoxamine for radiolabeling with Zirconium-89 (89Zr) for PET imaging, as well as fluorescence dies for immunofluorescence assays. The p-Tau mAb was evaluated in vitro for toxicity by MTT assay, LDH activity, propidium iodide/Annexin V assay, caspase-3, and mitochondrial membrane potential (MMP) assay in both mouse endothelial cell line (bEnd.3) and cortical primary neurons cell cultures. Importantly, non-toxic effects (up to concentrations of p-Tau mAb greater than 100 ug/mL) were detected. In vivo experiments in the tauopathy model mice (PS19) show that the 89Zr-pTau-mAb and 89Zr-Fragments-pTau-mAb are stable in circulation for up to 10 days without toxic effects. However, only less than 0.2% reached the brain, so further strategies have to be designed for crossing the Brain-Blood-Barrier (BBB). Moreover, an intraparenchymal treatment strategy was carried out. The PS19 mice were operated to implement osmotic pumps (Alzet 1004) at two different times, at 4 and 7 months, to stimulate the controlled release for one month each of the B6 antibody or the IgG1 control antibody. We demonstrated that B6-treated mice maintained their motor and memory abilities significantly compared with IgG1 treatment. In addition, we observed a significant reduction in p-Tau deposits in the brain. Conclusions /Discussion: A theragnostic pTau-mAb was developed. Moreover, we demonstrated that our p-Tau mAb recognizes very-early pathology forms of p-Tau by non-invasive techniques, such as PET. In addition, p-Tau mAb has non-toxic effects, both in vitro and in vivo. Although the p-Tau mAb is stable in circulation, only 0.2% achieve the brain. However, direct intraventricular treatment significantly reduces cognitive impairment in Alzheimer's animal models, as well as the accumulation of toxic p-Tau species.

Keywords: alzheimer's disease, theragnosis, tau, PET, immunotherapy, tauopathies

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Authors: Teka Haile, Behailu Hawulte, Solomon Alemayehu

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Background: HIV virological failure still remains a problem in HV/AIDS treatment and care. This study aimed to describe the prevalence and identify the factors associated with viral non-suppression among HIV-positive adult patients on antiretroviral therapy in Woliso Town, Oromia, Ethiopia. Methods: A retrospective cross-sectional study was conducted among 424 HIV-positive patient’s attending antiretroviral therapy (ART) in Woliso Town during the period from August 25, 2020 to August 30, 2020. Data collected from patient medical records were entered into Epi Info version 2.3.2.1 and exported to SPSS version 21.0 for analysis. Logistic regression analysis was done to identify factors associated with viral load non-suppression, and statistical significance of odds ratios were declared using 95% confidence interval and p-value < 0.05. Results: A total of 424 patients were included in this study. The mean age (± SD) of the study participants was 39.88 (± 9.995) years. The prevalence of HIV viral load non-suppression was 55 (13.0%) with 95% CI (9.9-16.5). Second-line ART treatment regimen (Adjusted Odds Ratio (AOR) = 8.98, 95% Confidence Interval (CI): 2.64, 30.58) and routine viral load testing (AOR = 0.01, 95% CI: 0.001, 0.02) were significantly associated with virological non-suppression. Conclusion: Virological non-suppression was high, which hinders the achievement of the third global 95 target. The second-line regimen and routine viral load testing were significantly associated with virological non-suppression. It suggests the need to assess the effectiveness of antiretroviral drugs for epidemic control. It also clearly shows the need to decentralize third-line ART treatment for those patients in need.

Keywords: virological non-suppression, HIV-positive, ART, Woliso town, Ethiopia

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Authors: Roxane A. Legaie, Kjiana E. Schwab, Caroline E. Gargett

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Studies looking at the changes in gene expression from RNAseq data often make use of linear models. It is also common practice to focus on a subset of data for a comparison of interest, leaving aside the samples not involved in this particular comparison. This work shows the importance of including all observations in the modeling process to better estimate variance parameters, even when the samples included are not directly used in the comparison under test. The human endometrium is a dynamic tissue, which undergoes cycles of growth and regression with each menstrual cycle. The mesenchymal stem cells (MSCs) present in the endometrium are likely responsible for this remarkable regenerative capacity. However recent studies suggest that MSCs also plays a role in the pathogenesis of endometriosis, one of the most common medical conditions affecting the lower abdomen in women in which the endometrial tissue grows outside the womb. In this study we compared gene expression profiles between MSCs and non-stem cell counterparts (‘non-MSC’) obtained from women with (‘E’) or without (‘noE’) endometriosis from RNAseq. Raw read counts were used for differential expression analysis using a linear model with the limma-voom R package, including either all samples in the study or only the samples belonging to the subset of interest (e.g. for the comparison ‘E vs noE in MSC cells’, including only MSC samples from E and noE patients but not the non-MSC ones). Using the full dataset we identified about 100 differentially expressed (DE) genes between E and noE samples in MSC samples (adj.p-val < 0.05 and |logFC|>1) while only 9 DE genes were identified when using only the subset of data (MSC samples only). Important genes known to be involved in endometriosis such as KLF9 and RND3 were missed in the latter case. When looking at the MSC vs non-MSC cells comparison, the linear model including all samples identified 260 genes for noE samples (including the stem cell marker SUSD2) while the subset analysis did not identify any DE genes. When looking at E samples, 12 genes were identified with the first approach and only 1 with the subset approach. Although the stem cell marker RGS5 was found in both cases, the subset test missed important genes involved in stem cell differentiation such as NOTCH3 and other potentially related genes to be used for further investigation and pathway analysis.

Keywords: differential expression, endometriosis, linear model, RNAseq

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Authors: Rupali Mane

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Cadmium sulfide (Cds) thin films were chemically deposited at room temperature, from aqueous ammonia solution using CdCl₂ (Cadmium chloride) as a Cd²⁺ and CS(NH₂)₂ (Thiourea) as S² ion sources. ‘as-deposited’ films were uniform, well adherent to the glass substrate, secularly reflective and yellowish in color. The ‘as-deposited ’Cds layers grew with nano-crystalline in nature and exhibit cubic structure, with blue-shift in optical band gap. The films were annealed in air atmosphere for two hours at different temperatures and further characterized for compositional, structural, morphological and optical properties. The XRD and SEM studies clearly revealed the systematic changes in morphological and structural form of Cds films with an improvement in the crystal quality. The annealed films showed ‘red-shift’ in the optical spectra after thermal treatment. The Thiourea modified CdS film could be good to provide solar cell application.

Keywords: cadmium sulfide, thin films, nano-crystalline, XRD

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Authors: Hala Obeid

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Among the cities that have been touched by hard events and have been experiencing this polemic of existence, one can quote Beirut. A city that defies and confronts itself for its own existence. Beirut materialized all the social complexity; it has also preserved the memory of a society that has been able to build and reflect a certain unique identity. In spite of its glory, Lebanon’s civil war has marked a turning point in Beirut’s history. It has caused many deaths and opposed religious communities. Once this civil war has ended, the reconstruction of the city center, however, saw the spatial exclusion of manual labor, small local commerce, and middle-class residences. The urban functions that characterized the pre-war center were removed, and the city’s spontaneous evolutions were replaced by a historical urban planning, which neglected the city’s memory and identity. The social and spatial fragmentation that has erupted since the war has led to a breakdown of spatial and social boundaries within the city. The aim of this study is to evaluate the impact of fragmentation and boundaries on the city of Beirut in spatial, social, religious and ethnic terms. The method used in this research is what we call the mixed method which is a combination between the quantitative method and the qualitative one. These two approaches, in this case, do not oppose but complement each other in order to study the city of Beirut physically and socially. The main purpose of the qualitative approach is to describe and analyze the social phenomenon of the fragmentation of the city; this method can be summarized by the field observation and study. While the quantitative approach is based on filling out questionnaires that leads to statistics analyzes. Together, these two approaches will mark the course of the research. As a result, Beirut is not only a divided city but is fragmented spatially into many fragments and socially into many groups. This fragmentation is creating immaterial boundaries between fragments and therefore between groups. These urban and social boundaries are specifically religious and ethnic limits. As a conclusion, one of the most important and discussed boundary in Beirut is a spatial and religious boundary called ‘the green line’ or the demarcation line, a true caesura within the city. It marks the opposition of two urban groups and the aggravated fragmentation between them. This line divided Beirut into two compartments: East Beirut (for Christians) and West Beirut (for Muslims). This green line has become an urban void that holds the past in suspension. Finally, to think of Beirut as an urban unit becomes an insoluble problem.

Keywords: Beirut, boundaries, fragmentation, identity

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Authors: Guillaume Schuchardt, Solenn Berson, Gerard Perrier

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Multi-junction solar cell configurations, where two sub-cells with complementary absorption are stacked and connected in series, offer an exciting approach to tackle the single junction limitations of organic solar cells and improve their power conversion efficiency. However, the augmentation of the number of layers has, as a consequence, to increase the risk of reducing the lifetime of the cell due to the ageing phenomena present at the interfaces. In this work, we study the intrinsic degradation mechanisms, under continuous illumination AM1.5G, inert atmosphere and room temperature, in single and tandem organic solar cells using Impedance Spectroscopy, IV Curves, External Quantum Efficiency, Steady-State Photocarrier Grating, Scanning Kelvin Probe and UV-Visible light.

Keywords: single and tandem organic solar cells, intrinsic degradation mechanisms, characterization: SKP, EQE, SSPG, UV-Visible, Impedance Spectroscopy, optical simulation

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Authors: Sarah Crawford, Gerry Lesley

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This research is a pre-clinical assessment of anti-cancer effects of novel non-steroidal diethyl stilbestrol-like estrogen analogs in estrogen-receptor positive/ progesterone-receptor positive human breast cancer microtumors of MCF 7 cell line. Tamoxifen analog formulation (Tam A1) was used as a single agent or in combination with therapeutic concentrations of 4-hydroxytamoxifen, currently used as a long-term treatment for the prevention of breast cancer recurrence in women with estrogen receptor positive/ progesterone receptor positive malignancies. At concentrations ranging from 30-50 microM, Tam A1 induced microtumor disaggregation and cell death. Incremental cytotoxic effects correlated with increasing concentrations of Tam A1. Live tumor microscopy showed that microtumos displayed diffuse borders and substrate-attached cells were rounded-up and poorly adherent. A complete cytotoxic effect was observed using 40-50 microM Tam A1 with time course kinetics similar to 4-hydroxytamoxifen. Combined treatment with TamA1 (30-50 microM) and 4-hydroxytamoxifen (10-15 microM) induced a highly cytotoxic, synergistic combined treatment response that was more rapid and complete than using 4-hydroxytamoxifen as a single agent therapeutic. Microtumors completely dispersed or formed necrotic foci indicating a highly cytotoxic combined treatment response. Moreover, breast cancer microtumors treated with both 4-hydroxytamoxifen and Tam A1 displayed lower levels of long-term post-treatment regrowth, a critical parameter of primary drug resistance, than observed for 4-hydroxytamoxifen when used as a single agent therapeutic. Tumor regrowth at 6 weeks post-treatment with either single agent 4-hydroxy tamoxifen, Tam A1 or a combined treatment was assessed for the development of drug resistance. Breast cancer cells treated with both 4-hydroxytamoxifen and Tam A1 displayed significantly lower levels of post-treatment regrowth, indicative of decreased drug resistance, than observed for either single treatment modality. The preclinical data suggest that combined treatment involving the use of tamoxifen analogs may be a novel clinical approach for long-term maintenance therapy in patients with estrogen-receptor positive/progesterone-receptor positive breast cancer receiving hormonal therapy to prevent disease recurrence. Detailed data on time-course, IC50 and tumor regrowth assays post- treatment as well as a proposed mechanism of action to account for observed synergistic drug effects will be presented.

Keywords: 4-hydroxytamoxifen, tamoxifen analog, drug-resistance, microtumors

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Authors: Rachida Houssa, Hassan Rhinane, Fadoumo Ali Malouw, Amina Oulmaalem

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Since the early 70s, the Moroccan Atlantic sea was subjected to the pressure of the bottom trawling, one of the most destructive techniques seabed that cause havoc on fishing catch, nonselective, and responsible for more than half of all releases of fish around the world. The present paper aims to map and assess the impact of the activity of the bottom trawling of the Moroccan Atlantic coast. For this purpose, a dataset of thirty years, between 1962 and 1999, from foreign fishing vessels using bottom trawling, has been used and integrated in a GIS. To estimate the extent and the importance of the geographical distribution of the trawling effort, the Moroccan Atlantic area was divided into a grid of cells of 25 km2 (5x5 km). This grid was joined to the effort trawling data, creating a new entity with a table containing spatial overlay grid with the polygon of swept surfaces. This mapping model allowed to quantify the used fishing effort versus time and to generate the trace indicative of trawling efforts on the seabed. Indeed, for a given year, a grid cell may have a swept area equal to 0 (never been touched by the trawl) or 25 km2 (the trawled area is similar to the cell size) or may be 100 km2 indicating that for this year, the scanned surface is four times the cell area. The results show that the total cumulative sum of trawled area is approximately 28,738,326 km2, scattered throughout the Atlantic coast. 95% of the overall trawling effort is located in the southern zone, between 29°N and 20°30'N. Nearly 5% of the trawling effort is located in the northern coastal region, north of 33°N. The center area between 33°N and 29°N is the least swept by Russian commercial vessels because in this region the majority of the area is rocky, and non trawlable.

Keywords: GIS, Moroccan Atlantic Ocean, seabed, trawling

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Authors: Mahya Naghipoor

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Purpose: Non-small cell lung cancer (NSCLC) is the most common lung cancer type. Epidermal growth factor receptor (EGFR) mutation is the main reason which causes NSCLC. Computed tomography (CT) is used for diagnosis and prognosis of lung cancers because of low price and little invasion. Semantic analyses of qualitative CT features are based on visual evaluation by radiologist. However, the naked eye ability may not assess all image features. On the other hand, radiomics provides the opportunity of quantitative analyses for CT images features. The aim of this review study was comparing accuracy of semantic and radiomics features in prognosis of EGFR mutation in NSCLC. Methods: For this purpose, the keywords including: non-small cell lung cancer, epidermal growth factor receptor mutation, semantic, radiomics, feature, receiver operating characteristics curve (ROC) and area under curve (AUC) were searched in PubMed and Google Scholar. Totally 29 papers were reviewed and the AUC of ROC analyses for semantic and radiomics features were compared. Results: The results showed that the reported AUC amounts for semantic features (ground glass opacity, shape, margins, lesion density and presence or absence of air bronchogram, emphysema and pleural effusion) were %41-%79. For radiomics features (kurtosis, skewness, entropy, texture, standard deviation (SD) and wavelet) the AUC values were found %50-%86. Conclusions: In conclusion, the accuracy of radiomics analysis is a little higher than semantic in prognosis of EGFR mutation in NSCLC.

Keywords: lung cancer, radiomics, computer tomography, mutation

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Authors: Saskya E. Carrera P., Ben Hankamer, Melanie Oey

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The green alga C. reinhardtii provides a platform for the cheap, scalable, and safe production of complex proteins. Despite gene expression in photosynthetic organisms being tightly regulated by light, most expression studies have analysed chloroplast recombinant protein production under constant light. Here the influence of illumination time and intensity on GFP and a GFP-PlyGBS (bacterial-lysin) fusion protein expression was investigated. The expression of both proteins was strongly influenced by the light regime (6-24 hr illumination per day), the light intensity (0-450 E m⁻²s⁻¹) and growth condition (photoautotrophic, mixotrophic and heterotrophic). Heterotrophic conditions resulted in relatively low recombinant protein yields per unit volume, despite high protein yields per cell, due to low growth rates. Mixotrophic conditions exhibited the highest yields at 6 hrs illumination at 200µE m⁻²s⁻¹ and under continuous low light illumination (13-16 mg L⁻¹ GFP and 1.2-1.6 mg L⁻¹ GFP-PlyGBS), as these conditions supported good cell growth and cellular protein yields. A ~23-fold increase in protein accumulation per cell and ~9-fold increase L⁻¹ culture was observed compared to standard constant 24 hr illumination for GFP-PlyGBS. The highest yields under photoautotrophic conditions were obtained under 9 hrs illumination (6 mg L⁻¹ GFP and 2.1 mg L⁻¹ GFP-PlyGBS). This represents a ~4-fold increase in cellular protein accumulation for GFP-PlyGBS. On a volumetric basis the highest yield was at 15 hrs illumination (~2-fold increase L⁻¹ over the constant light for GFP-PlyGBS). Optimising illumination conditions to balance growth and protein expression can thus significantly enhance overall recombinant protein production in C. reinhardtii cultures.

Keywords: chlamydomonas reinhardtii, light, mixotrophic, recombinant protein

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Authors: R. Alramyan, S. Alsalamah, R. Alrashed, R. Alakel, F. Altheyeb, M. Alessa

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Background: Nutritional support with total parenteral nutrition (TPN) is usually commenced with hematopoietic stem cell transplantation (HSCT) patients. However, it has its benefits and risks. Complications related to central venous catheter such as infections, and metabolic disturbances, including abnormal liver function, is usually of concern in such patients. Methods: A retrospective charts review of all pediatric patients who underwent HSCT between the period 2015-2018 in a tertiary hospital in Riyadh, Saudi Arabia. Patients' demographics, types of conditioning, type of nutrition, and patients' outcomes were collected. Statistical analysis was conducted using SPSS version 22. Frequencies and percentages were used to describe categorical variables. Mean, and standard deviation were used for continuous variables. A P value of less than 0.05 was considered as statically significant. Results: a total of 162 HSCTs were identified during the period mentioned. Indication of allogenic transplant included hemoglobinopathy in 50 patients (31%), acute lymphoblastic leukemia in 21 patients (13%). TPN was used in 96 patients (59.30%) for a median of 14 days, nasogastric tube feeding (NGT) in 16 (9.90%) patients for a median of 11 days, and 71 of patients (43.80%) were able to tolerate oral feeding. Out of the 96 patients (59.30%) who were dependent on TPN, 64 patients (66.7%) had severe mucositis in comparison to 17 patients (25.8%) who were either on NGT or tolerated oral intake. (P-value= 0.00). Sinusoidal obstruction syndrome (SOS) was seen in 14 patients (14.6%) who were receiving TPN compared to none in non-TPN patients (P=value 0.001). Moreover, majority of patients who had SOS received myeloablative conditioning therapy for non-malignant disease (hemoglobinopathy). However, there were no statistically significant differences in Graft-vs-Host Disease (both acute and chronic), bacteremia, and patient outcome between both groups. Conclusions: Nutritional support using TPN is used in majority of patients, especially post-myeloablative conditioning associated with severe mucositis. TPN was associated with VOD, especially in hemoglobinopathy patients who received myeloablative therapy. This may emphasize on use of preventative measures such as fluid restriction, use of diuretics, or defibrotide in high-risk patients.

Keywords: hematopoeitic stem cell transplant, HSCT, stem cell transplant, sinusoidal obstruction syndrome, total parenteral nutrition

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Authors: Rostyslav Horbay, Nick Korolis, Vahid Anvari, Rostyslav Stoika

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Introduction: Giant cancer cells (GCC) are common in all types of cancer, especially after poor therapy. Some specific features of such cells include ~10-fold enlargement, drug resistance, and the ability to propagate similar daughter cells. We used murine NK/Ly lymphoma, an aggressive and fast growing lymphoma model that has already shown drastic changes in GCC comparing to parental cells (chromatin condensation, nuclear fragmentation, tighter OXPHOS/cellular respiration coupling, multidrug resistance). Materials and methods: In this study, we compared morpho-functional changes of GCC that predominantly show either a cytostatic or a cytotoxic effect after treatment with drugs. We studied the effect of a combined cytostatic/cytotoxic drug treatment to determine the correlation of drug efficiency and GCC formation. Doses of G1/S-specific drug paclitaxel/PTX (G2/M-specific, 50 mg/mouse), vinblastine/VBL (50 mg/mouse), and DNA-targeting agents doxorubicin/DOX (125 ng/mouse) and cisplatin/CP (225 ng/mouse) on C57 black mice. Several tests were chosen to estimate morphological and physiological state (propidium iodide, Rhodamine-123, DAPI, JC-1, Janus Green, Giemsa staining and other), which included cell integrity, nuclear fragmentation and chromatin condensation, mitochondrial activity, and others. A single and double factor ANOVA analysis were performed to determine correlation between the criteria of applied drugs and cytomorphological changes. Results: In all cases of treatment, several morphological changes were observed (intracellular vacuolization, membrane blebbing, and interconnected mitochondrial network). A lower gain in ascites (49.97% comparing to control group) and longest lifespan (22+9 days) after tumor injection was obtained with single VBL and single DOX injections. Such ascites contained the highest number of GCC (83.7%+9.2%), lowest cell count number (72.7+31.0 mln/ml), and a strong correlation coefficient between increased mitochondrial activity and percentage of giant NK/Ly cells. A high number of viable GCC (82.1+9.2%) was observed compared to the parental forms (15.4+11.9%) indicating that GCC are more drug resistant than the parental cells. All this indicates that the giant cell formation and its ability to obtain drug resistance is an expanding field in cancer research.

Keywords: ANOVA, cisplatin, doxorubicin, drug resistance, giant cancer cells, NK/Ly lymphoma, paclitaxel, vinblastine

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Authors: Chen-Yu Chen, Wei-Mon Yan, Chi-Nan Lai, Jian-Hao Su

Abstract:

The proton exchange membrane fuel cell (PEMFC) becomes more important as an alternative energy source recently. Maintaining proper water content in the membrane is one of the key requirements for optimizing the PEMFC performance. The planar membrane humidifier has the advantages of simple structure, low cost, low-pressure drop, light weight, reliable performance and good gas separability. Thus, it is a common external humidifier for PEMFCs. In this work, a planar membrane humidifier for kW-scale PEMFCs is developed successfully. The heat and mass transfer of humidifier is discussed, and its performance is analyzed in term of dew point approach temperature (DPAT), water vapor transfer rate (WVTR) and water recovery ratio (WRR). The DPAT of the humidifier with the counter flow approach reaches about 6°C under inlet dry air of 50°C and 60% RH and inlet humid air of 70°C and 100% RH. The rate of pressure loss of the humidifier is 5.0×10² Pa/min at the torque of 7 N-m, which reaches the standard of commercial planar membrane humidifiers. From the tests, it is found that increasing the air flow rate increases the WVTR. However, the DPAT and the WRR are not improved by increasing the WVTR as the air flow rate is higher than the optimal value. In addition, increasing the inlet temperature or the humidity of dry air decreases the WVTR and the WRR. Nevertheless, the DPAT is improved at elevated inlet temperatures or humidities of dry air. Furthermore, the performance of the humidifier with the counter flow approach is better than that with the parallel flow approach. The DPAT difference between the two flow approaches reaches up to 8 °C.

Keywords: heat and mass transfer, humidifier performance, PEM fuel cell, planar membrane humidifier

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Authors: Ahmed M. Haddad, Hadeel S. El-Shaal, Gadallah M. Abu-Elreesh

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Some of filamentous fungi can be used for biodiesel production as they are able to accumulate high amounts of intracellular lipids when grown at stress conditions. Aspergillus fumigatus sp. was isolated from Nile delta soil in Egypt. The fungus was primarily screened for its capacity to accumulate lipids using Nile red staining assay. The fungus could accumulate more than 20% of its biomass as lipids when grown at optimized minimal medium. After lipid extraction, we could use fungal cell debris to remove some heavy metals from contaminated waste water. The fungal cell debris could remove Cd, Cr, and Zn with absorption efficiency of 73%, 83.43%, and 69.39% respectively. In conclusion, the Aspergillus fumigatus isolate may be considered as a promising biodiesel producer, and its biomass waste can be further used for bioremediation of wastewater contaminated with heavy metals.

Keywords: biodiesel, bioremediation, fungi, heavy metals, lipids, oleaginous

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Authors: Yongfang Deng, Dunwen Zuo

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An attempt is made here to join 2024 aluminum alloy plate by friction stir joining (FSJ) using different types of tools. Joint surface morphology was observed, and both arc line spacing and flash were measured. Study is carried out on the effect of pin, shoulder and eccentricity of the tool on the surface topography of the joint and the formation of the joint surface topography is analyzed. It is found that, eccentric squeezing action of the tool is the mainly motive power to form arc lines contour and flash structure. Little flash appears in the advancing side but with severe deformation, while the flash in the retreating side is heavy but with soft deformation. The pin of tool has a deep impact on the flash on the advancing side of the joints. Shoulder can widen the arc lines, refine arcs structure, reduce flash in the retreat side, but will increase the flash in the advancing side. Increasing the amount of eccentricity, it has litter effect on the arc line spacing but will destroy the arc lines morphology in the joint surface and promote the formation of filamentous flash structure in the joint.

Keywords: FSJ, surface morphology, tool, joint

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