2,750 research outputs found

    THE EFFECT OF PRETREATMENT WITH TOLL-LIKE RECEPTOR 4 ANTAGONIST RESATORVID ON METHOTREXATE-INDUCED LIVER INJURY IN RATS: HISTOPATHOLOGICAL STUDY

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    Objective: This research aims to evaluate the histopathological changes after pretreatment with resatorvid against methotrexate induced-liver injury.Methods: 28 male albino-wistar rats divided into random 4 groups (7 rats in each). Control group: Rats left untreated. Vehicle pre-treated group: Rats were administered dimethyl sulfoxide (DMSO) followed by methotrexate (MTX). Methotrexate treated group: Rats left untreated then administered MTX. Resatorvid pre-treated group: Rats were administered resatorvid followed by MTX. 24 h after the end of treatment, the animals were sacrificed. Liver tissue samples dissected out immediately and fixed in 10% formalin. The traditional procedures (paraffin-embedded method) was used to prepare liver tissue for microscopic evaluation by none alcoholic fatty liver disease (NAFLD) Activity Score Components.Results: Liver tissue sections of MTX-treated group show moderate-to-severe steatosis of hepatic cells and micro- and macro- hepatocellular fatty degeneration and giant fatty cysts with chronic inflammatory cells infiltration. While liver tissue sections of the resatorvid pre-treated group show moderate hepatic cellular fatty degeneration, with a decreased number of fatty cysts chains and the inflammation disappeared.Conclusion: Resatorvid hepatoprotective effect against MTX-induced injury was promising throughout resolving the accompanying inflammation and partial restoring histopathological fatty alterations

    Identifying Difficult exercises in an eTextbook Using Item Response Theory and Logged Data Analysis

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    The growing dependence on eTextbooks and Massive Open Online Courses (MOOCs) has led to an increase in the amount of students' learning data. By carefully analyzing this data, educators can identify difficult exercises, and evaluate the quality of the exercises when teaching a particular topic. In this study, an analysis of log data from the semester usage of the OpenDSA eTextbook was offered to identify the most difficult data structure course exercises and to evaluate the quality of the course exercises. Our study is based on analyzing students' responses to the course exercises. We applied item response theory (IRT) analysis and a latent trait mode (LTM) to identify the most difficult exercises .To evaluate the quality of the course exercises we applied IRT theory. Our findings showed that the exercises that related to algorithm analysis topics represented the most difficult exercises, and there existing six exercises were classified as poor exercises which could be improved or need some attention.Comment: 6 pages,5 figure

    Correlation of ABO Blood Groups and Rh Factor with The Severity of Generalized Chronic Periodontitis: Across Sectional Study in Riyadh, Saudi Arabia

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    BACKGROUND: The development of periodontal diseases depends on the presence of causative microorganisms, host immunity and risk factors. Although variability present among the types of periodontal diseases, all are represented to a shared interaction between host and bacteria. ABO blood groups are the most investigated erythrocyte antigen system. However, limited investigations have been conducted to explore the alliance between ABO blood groups and periodontal diseases. AIM: Our purpose was to explore any possible association between the severity of chronic periodontitis with ABO blood groups and Rh factor. METHODS: A cross-sectional study was carried out on 205 patients out of 1126 generalised chronic periodontitis patients (GCP) who were referred to Al-Farabi Colleges, Riyadh, Saudi Arabia. They were categorized into; group I (mild), group II (moderate) and group III (sever). RESULTS: The patients with blood group O were at a greater risk to develop GCP irrespective of its severity, followed by those with blood group A, B, and AB. The dispensation of the Rh factor in all groups exhibited a significantly greater distribution of Rh positive. CONCLUSION: Genetic factors such as ABO blood group antigens may act as a risk influencer that affects the progression and severity of the chronic periodontitis

    Resilience to flash floods in wetland communities of northeastern Bangladesh

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    Globally, a number of catastrophic hydrometeorological hazards occurred in 2017 among which the monsoon floods in South Asia was particularly disastrous, killing nearly 1200 people in India, Nepal and Bangladesh. The wetland region (Haor) of northeastern (NE) Bangladesh was severely affected by flash floods early in 2017, affecting nearly 1 million households and damaging US $450 million worth of rice crops. This study investigates how the NE Bangladesh experienced the 2017 flash floods, and to what degree the wetland communities are vulnerable and resilience to flash floods. Focus group discussion, key informant interviews, and household questionnaire surveys (n = 80) were applied in the study area of Sunamganj district. Results from statistical analyses and regression modelling reveal that poor people are particularly vulnerable to floods but they are also more adaptive and thus resilient; middle-income households are vulnerable as they are hesitant to take up any jobs and accept flood relief; and rich households, despite being less adaptive, are able to recover from flood disasters because of wealth. This study reveals that resilience also stems from deep religious faith in the Haor inhabitants that supports communities to move on by accepting that most natural calamities such as flash floods are divine tests. This study also finds that women are particularly vulnerable and less resilient as they are not normally allowed to work outside of their homes and beyond the Haor communities due to cultural and religious reasons

    Markers characterizing corneal damage during aging of rat

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    Aging is a biological phenomenon that involves an increase of oxidative stress associated with gradual degradation of the structure and function of the cornea. Gender differences and subsequent deterioration of cornea is an interesting topic, especially yet few data are available concerning the impact of age, especially on the corneal. One hundred male and female Wistar albino rats ages 3, 6, 18, 24, and 30 months (n=10 equal for male and female) were used. At the time interval, cornea were investigated by light and transmission electron microscopy (TEM), immunohistochemistry of caspase 3 (casp3), glial fibrillar acidic protein(GFAP) and CD45 and  flow cytometry of DNA, bcl-2-like protein 4 (BAX), transforming growth factor beta (TGF-β) and Cd45 (lymphocyte common antigen). Light and TEM investigation  revealed apparent deterioration of atrophy of corneal epithelium with vesicular vacuolar degeneration, hyalinization of stromal collagen fibrils and swelling and degeneration of the endothelial lining the descemet's membrane. There was apparent loss of keratocytes within corneal stroma. Immunohistochemistry of casp 3 and CD45 were markedly increased manifesting cell damage. GFAP showed apparent reduction of innervation of corneal stroma and endothelium layer. Flow cytometry of DNA, Bax and TGF revealed increased apoptic cell death of cornea of 30M-old rats. We concluded that aging contributed to an apparent increase of cellular damage of different corneal region associated with alterations of cell markers

    Environmental life cycle assessment and techno-economic analysis of triboelectric nanogenerators

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    As the world economy grows and industrialization of the developing countries increases, the demand for energy continues to rise. Triboelectric nanogenerators (TENGs) have been touted as having great potential for low-carbon, non-fossil fuel energy generation. Mechanical energies from, amongst others, body motion, vibration, wind and waves are captured and converted by TENGs to harvest electricity, thereby minimizing global fossil fuel consumption. However, only by ascertaining performance efficiency along with low material and manufacturing costs as well as a favorable environmental profile in comparison with other energy harvesting technologies, can the true potential of TENGs be established. This paper presents a detailed techno-economic lifecycle assessment of two representative examples of TENG modules, one with a high performance efficiency (Module A) and the other with a lower efficiency (Module B) both fabricated using low-cost materials. The results are discussed across a number of sustainability metrics in the context of other energy harvesting technologies, notably photovoltaics. Module A possesses a better environmental profile, lower cost of production, lower CO2 emissions and shorter energy payback period (EPBP) compared to Module B. However, the environmental profile of Module B is slightly degraded due to the higher content of acrylic in its architecture and higher electrical energy consumption during fabrication. The end of life scenario of acrylic is environmentally viable given its recyclability and reuse potential and it does not generate toxic gases that are harmful to humans and the environment during combustion processes due to its stability during exposure to ultraviolet radiation. Despite the adoption of a less optimum laboratory manufacturing route, TENG modules generally have a better environmental profile than commercialized Si based and organic solar cells, but Module B has a slightly higher energy payback period than PV technology based on perovskite-structured methyl ammonium lead iodide. Overall, we recommend that future research into TENGs should focus on improving system performance, material optimization and more importantly improving their lifespan to realize their full potential
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