1,982 research outputs found
Temperature Dependence of a Sub-wavelength Compact Graphene Plasmon-Slot Modulator
We investigate a plasmonic electro-optic modulator with an extinction ratio
exceeding 1 dB/um by engineering the optical mode to be in-plane with the
graphene layer, and show how lowering the operating temperature enables steeper
switching. We show how cooling Graphene enables steeping thus improving dynamic
energy consumption. Further, we show that multi-layer Graphene integrated with
a plasmonic slot waveguide allows for in-plane electric field components, and
3-dB device lengths as short as several hundred nanometers only. Compact
modulators approaching electronic length-scales pave a way for ultra-dense
photonic integrated circuits with smallest footprint
Christmas Disease (Hemophilia B) A Case Report
We report a 25 years old man developed Haemarthrosis of left hip joint with a history of recurrent swelling and pain in multiple joints and prolonged bleeding following minor trauma since childhood. Subsequent investigations revealed Christmas disease (Haemophilia B). Hemophilia B is an X-linked bleeding disorder. This case emphasises the importance of considering a diagnosis of haemophilia in a man with unexplained bleeding, even in the absence of a positive family history. DOI: 10.3329/bsmmuj.v2i2.4766 BSMMU J 2009; 2(2): 90-9
A modified routine analysis of arsenic content in drinking-water in Bangladesh by hydride generation-atomic absorption spectrophotometry.
The high prevalence of elevated levels of arsenic in drinking-water in many countries, including Bangladesh, has necessitated the development of reliable and rapid methods for the determination of a wide range of arsenic concentrations in water. A simple hydride generation-atomic absorption spectrometry (HG-AAS) method for the determination of arsenic in the range of microg/L to mg/L concentrations in water is reported here. The method showed linearity over concentrations ranging from 1 to 30 microg/L, but requires dilution of samples with higher concentrations. The detection limit ranged from 0.3 to 0.5 microg/L. Evaluation of the method, using internal quality-control (QC) samples (pooled water samples) and spiked internal QC samples throughout the study, and Standard Reference Material in certain lots, showed good accuracy and precision. Analysis of duplicate water samples at another laboratory also showed good agreement. In total, 13,286 tubewell water samples from Matlab, a rural area in Bangladesh, were analyzed. Thirty-seven percent of the water samples had concentrations below 50 microg/L, 29% below the WHO guideline value of 10 microg/L, and 17% below 1 microg/L. The HG-AAS was found to be a precise, sensitive, and reasonably fast and simple method for analysis of arsenic concentrations in water samples
TAT-peptide conjugated repurposing drug against SARS-CoV-2 main protease (3CLpro): potential therapeutic intervention to combat COVID-19
The Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that originated in Chinese city of Wuhan has caused around 906,092 deaths and 28,040,853 confirmed cases worldwide (WHO, 11 September, 2020). In a life-threatening situation, where there is no specific and licensed anti-COVID-19 vaccine or medicine available; the repurposed drug might act as a silver bullet. Currently, more than 211 vaccines, 80 antibodies, 31 antiviral drugs, 35 cell-based, 6 RNA-based and 131 other drugs are in clinical trials. It is therefore utter need of the hour to develop an effective drug that can be used for the treatment of COVID-19 before a vaccine can be developed. One of the best-characterized and attractive drug targets among coronaviruses is the main protease (3CL^{pro}). Therefore, the current study focuses on the molecular docking analysis of TAT-peptide^{47–57} (GRKKRRQRRRP)-conjugated repurposed drugs (i.e., lopinavir, ritonavir, favipiravir, and hydroxychloroquine) with SARS-CoV-2 main protease (3CL^{pro} to discover potential efficacy of TAT-peptide (TP) - conjugated repurposing drugs against SARS-CoV-2. The molecular docking results validated that TP-conjugated ritonavir, lopinavir, favipiravir, and hydroxychloroquine have superior and significantly enhanced interactions with the target SARS-CoV-2 main protease. In-silico approach employed in this study suggests that the combination of the drug with TP is an excelling alternative to develop a novel drug for the treatment of SARS-CoV-2 infected patients. The development of TP based delivery of repurposing drugs might be an excellent approach to enhance the efficacy of the existing drugs for the treatment of COVID-19. The predictions from the results obtained provide invaluable information that can be utilized for the choice of candidate drugs for in vitro, in vivo and clinical trials. The outcome from this work prove crucial for exploring and developing novel cost-effective and biocompatible TP conjugated anti-SARS-CoV-2 therapeutic agents in immediate future
Prevalence of HCV and HIV infections in 2005-Earthquake-affected areas of Pakistan
<p>Abstract</p> <p>Background</p> <p>On October 8, 2005, an earthquake of magnitude 7.6 hit the Northern parts of Pakistan. In the post-earthquake scenario, overcrowding, improper sewage disposal, contamination of food and drinking water, hasty surgical procedures, and unscreened blood transfusions to earthquake victims most likely promotes the spread of infections already prevalent in the area.</p> <p>Objective</p> <p>The objective of the study reported here was to determine the prevalence of Human Immunodeficiency and Hepatitis C viruses (respectively, HIV and HCV) in the earthquake-affected communities of Pakistan. The samples were analyzed 2 months and then again 11 months after the earthquake to estimate the burden of HIV and HCV in these areas, and to determine any rise in the prevalence of these viral infections as a result of the earthquake.</p> <p>Methods</p> <p>Blood samples were initially collected during December, 2005 to March 2006, from 245 inhabitants of the earthquake-affected areas. These samples were screened for HCV and HIV, using immunochromatography and Enzyme-Linked Immuno-Sorbent Assay (ELISA).</p> <p>Results</p> <p>Out of 245 samples tested, 8 (3.26%) were found positive for HCV, and 0 (0.0%) for HIV, indicating the existence of HCV infection in the earthquake-stricken areas. The same methods were used to analyze the samples collected in the second round of screening in the same area, in September, 2006 – 11 months after the earthquake. This time 290 blood samples were collected, out of which 16 (5.51%) samples were positive for HCV, and 0 for HIV.</p> <p>Conclusion</p> <p>A slightly higher prevalence of HCV was recorded 11 months after the earthquake; this increase, however, was not statistically significant. None of the study participants was found HIV-infected.</p
Isorhamnetin induces apoptosis and suppresses metastasis of human endometrial carcinoma Ishikawa cells via endoplasmic reticulum stress promotion and matrix metalloproteinase-2/9 inhibition in vitro and in vivo
Endometrial cancer (EC) is a very common female cancer which has attracted more and more attention. According to the individual patient’s condition, the current treatment of EC patients is mainly based on surgery, which is supplemented by chemotherapy, radiotherapy, and endocrine intervention. However, these existing treatment strategies also have some inevitable limitations. Therefore, it is particularly important to find an active ingredient with low toxicity and a high safety profile against EC. Isorhamnetin is a flavonoid known to be present in a variety of plants, such as sea buckthorn, dry willow, and wolfberry. In recent years, the anti-tumor effects of isorhamnetin have been reported. In our study, isorhamnetin was shown to induce apoptosis in Ishikawa cells by inducing the endogenous mitochondrial apoptotic pathway and exogenous death receptor pathway, promoting the endoplasmic reticulum stress-related pathway, and activating the corresponding markers of UPR response. In addition, isorhamnetin affected the expression of MMP2 and MMP9-related proteins in vitro and in vivo and eventually repressed metastasis. Therefore, isorhamnetin can be used as a promising medicinal material for the treatment of EC
Prevalence and predictors of binge eating disorder symptoms among a sample of university students in Bangladesh: a cross-sectional survey
Background and Aims:Â There is a dearth of information about binge eating disorder (BED) among Bangladeshi university students, who may be more susceptible to BED due to the rise in unhealthy lifestyles and food habits. Therefore, the purpose of this study was to assess the prevalence and associated factors of BED symptoms among Bangladeshi university students.
Methods: Students (N = 525) from three public universities in Bangladesh participated in this cross-sectional study between November 2022 and March 2023. Face-to-face interviews were conducted using a structured paper-based questionnaire that included two validated survey tools; the binge eating disorder screener and the patient health questionnaire-9. To identify the factors associated with BED symptoms, multiple logistic regression analysis was conducted, with sociodemographic and behavioral information (e.g., age, sex, smoking status, etc.) considered as covariates.
Results: The prevalence of BED symptoms among participants (mean age 21.28 years, 50.3% male and 49.7% female) was 20.6%. Male students had a 2.28 times higher likelihood of having BED symptoms compared to female counterparts (adjusted odds ratio [AOR] = 2.28; 95% CI: 1.33−3.89). Older students (AOR = 3.56, 95% CI: 1.80−7.05), students who were overweight or obese (AOR = 3.32, 95% CI: 1.87−5.89), and students reporting higher depressive symptoms (AOR = 2.69, 95% CI: 1.66−4.35) were at greater risk for developing BED compared to their respective counterparts.
Conclusions:Â This study provides new insights into the prevalence of BED symptoms and its contributing factors among Bangladeshi students. Approximately 1-in-5 university students reported having BED symptoms. University students who are older, overweight, or obese, and who report depressive symptoms may be at greatest risk. Future longitudinal studies are needed to determine the causal factors underlying BED. Findings from this study can assist policymakers and public health professionals in developing effective and targeted strategies to mitigate the risks associated with BED among Bangladeshi university students
HIV-1 subtype A infection in a community of intravenous drug users in Pakistan
BACKGROUND: Data on the subtypes of HIV in a population help in predicting the potential foci of epidemic, tracking the routes of infection and following the patterns of the virus' genetic divergence. Globally, the most prevalent HIV infection is the HIV-1 subtype C. In Asia, predominant subtypes of HIV-1 are B, C, and CRF-01AE. During the last few years, HIV prevalence in Pakistan has taken the form of a concentrated epidemic in at least two high risk groups, namely, Intravenous Drug Users (IDUs) and Male Sex Workers (MSWs). Factors that have facilitated the proliferation of HIV infection include transmission through a large number of repatriates and needle-sharing intravenous drug users, unscreened blood transfusions, and sexual illiteracy. The HIV subtypes infecting Pakistani populations have not been explored to date. In this study, we analyzed HIV-1 subtypes from in a high-risk community of IDUs in Karachi, the largest city of Pakistan. METHODS: Samples were collected from 34 IDUs after their informed consent. In addition, the study subjects were administered a questionnaire regarding their sexual behavior and travel history. For HIV analysis, DNA was extracted from the samples and analyzed for HIV types and subtypes using subtype-specific primers in a nested polymerase chain reaction (PCR). The results from this PCR were further confirmed using the Heteroduplex Mobility Assay (HMA). RESULTS: We found HIV-1 subtype A in all the 34 samples analyzed. A few of the study subjects were found to have a history of travel and stay in the United Arab Emirates. The same subjects also admitted to having contact with commercial sex workers during their stay abroad. CONCLUSION: Our study therefore shows clade A HIV-1 to be prevalent among the IDUs in Karachi. As the prevalence of HIV in Pakistan continues to rise, more work needs to be done to track the infection, and to analyze the strains of HIV spreading through the country
Multi-ancestry genetic analysis of gene regulation in coronary arteries prioritizes disease risk loci
Genome-wide association studies (GWASs) have identified hundreds of risk loci for coronary artery disease (CAD). However, non-European populations are underrepresented in GWASs, and the causal gene-regulatory mechanisms of these risk loci during atherosclerosis remain unclear. We incorporated local ancestry and haplotypes to identify quantitative trait loci for expression (eQTLs) and splicing (sQTLs) in coronary arteries from 138 ancestrally diverse Americans. Of 2,132 eQTL-associated genes (eGenes), 47% were previously unreported in coronary artery; 19% exhibited cell-type-specific expression. Colocalization revealed subgroups of eGenes unique to CAD and blood pressure GWAS. Fine-mapping highlighted additional eGenes, including TBX20 and IL5. We also identified sQTLs for 1,690 genes, among which TOR1AIP1 and ULK3 sQTLs demonstrated the importance of evaluating splicing to accurately identify disease-relevant isoform expression. Our work provides a patient-derived coronary artery eQTL resource and exemplifies the need for diverse study populations and multifaceted approaches to characterize gene regulation in disease processes.</p
Multi-ancestry genetic analysis of gene regulation in coronary arteries prioritizes disease risk loci
Genome-wide association studies (GWASs) have identified hundreds of risk loci for coronary artery disease (CAD). However, non-European populations are underrepresented in GWASs, and the causal gene-regulatory mechanisms of these risk loci during atherosclerosis remain unclear. We incorporated local ancestry and haplotypes to identify quantitative trait loci for expression (eQTLs) and splicing (sQTLs) in coronary arteries from 138 ancestrally diverse Americans. Of 2,132 eQTL-associated genes (eGenes), 47% were previously unreported in coronary artery; 19% exhibited cell-type-specific expression. Colocalization revealed subgroups of eGenes unique to CAD and blood pressure GWAS. Fine-mapping highlighted additional eGenes, including TBX20 and IL5. We also identified sQTLs for 1,690 genes, among which TOR1AIP1 and ULK3 sQTLs demonstrated the importance of evaluating splicing to accurately identify disease-relevant isoform expression. Our work provides a patient-derived coronary artery eQTL resource and exemplifies the need for diverse study populations and multifaceted approaches to characterize gene regulation in disease processes.</p
- …