BackgroundOur present study was conducted to characterize the phytoconstituents present in the aqueous extract of Momordica charantia and evaluate the antimicrobial efficacy of silver-extract nanoparticles (Ag-Extract-NPs).MethodsSilver nanoparticles (AgNPs) were prepared by reducing AgNO3; and NaBH4 served as reducing agent. After screening of phytochemicals; AgNPs and aqueous extract were mixed thoroughly and then coated by polyaniline. These NPs were characterized by using Visual inspection, UV spectroscopy, FTIR, SEM and TEM techniques. Antimicrobial activities were assessed against Staphylococcus aureus, Salmonella typhi, Escherichia coli and Pseudomonas aeruginosa.ResultsAqueous extract of M. charantia fruits contain alkaloid, phenol, saponin etc. UV–Vis spectrum showed strong absorption peak around 408 nm. The presence of –CH, −NH, −COOH etc. stretching in FTIR spectrum of Ag-Extract-NPs endorsed that AgNPs were successfully capped by bio-compounds. SEM and TEM result revealed that synthesized NPs had particle size 78.5–220 nm. Ag-Extract-NPs showed 34.6 ± 0.8 mm zone of inhibition against E. coli compared to 25.6 ± 0.5 mm for ciprofloxacin. Maximum zone of inhibition for Ag-Extract-NPs were 24.8 ± 0.7 mm, 26.4 ± 0.4 mm, 7.4 ± 0.4 mm for S. aureus, P. aeruginosa and S. typhi. We found that Ag-Extract-NPs have much better antibacterial efficacy than AgNPs and M. charantia extract has individually. It is also noticed that gram negative bacteria (except S. typhi) are more susceptible to Ag-Extract-NPs than gram positive bacteria.ConclusionAg-Extract-NPs showed strong antibacterial activity. In order to make a reliable stand for mankind, further study is needed to consider determining the actual biochemical pathway by which AgNPs-extracts exert their antimicrobial effect.Electronic supplementary materialThe online version of this article (doi:10.1186/s12906-017-1843-8) contains supplementary material, which is available to authorized users.

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Aluminium (Al) toxicity in the soil is an important factor that limits the production of barley in areas with acid soil. Selection and breeding of barley cultivars tolerant to Al toxicity is one of the most useful approaches to increase productivity. A reliable screening system is very important for selecting Al-tolerant plants in a breeding program. Using a hydroponic culture technique in which all the treatments were isolated in order to minimise complex interaction between genotypes, experiments were conducted to distinguish between susceptible and tolerant cultivars. Three different methods were investigated. Two previously reported methods could not provide consistent results or detect the difference between tolerant and susceptible cultivars. A new method was developed as follows: pre-germinated seedlings (2 days at 22°C) were cultured for 3 days in nutrient solution (Al free) followed by 24 h growing in a solution with 50 or 100 µm Al, and then 48 h regrowth in Al free nutrient solution. Following this method, seminal root regrowth length (SRRL) and relative seminal root regrowth length (RSRRL) showed significant differences between tolerant and sensitive cultivars. The SRRL of the most tolerant cultivar, Dayton, was 4–8 times greater than of the sensitive cultivars and about twice as long as of the other tolerant cultivars, FM404 and Brindabella. All the sensitive cultivars showed significantly shorter SRRL or RSRRL. Both SRRL and RSRRL were found to be closely correlated with plant height, plant dry weight, and grain weight in a soil-based experiment. This method was also used to evaluate F2 populations from crosses between tolerant and susceptible cultivars. Both SRRL and RSRRL gave results consistent with the hypothesis that the tolerance was controlled by a single dominant gene.

Background: The presence of ischemic ECG changes on admission has been shown to predict outcome, the relationship between the extent of ECG changes and the risk of cardiac events is still ill   defined. The severity of ST-segment depression on admission ECG has a strong association with   adverse in-hospital outcome in patients with non ST-segment elevation acute coronary syndrome. The study was done to observe the extent of ST-segment depression and in-hospital outcome in patients with non ST-segment elevation acute coronary syndrome.   Methods: This study was conducted in the Department of Cardiology in NICVD Dhaka, from   January 2006 to December 2007. Considering inclusion and exclusion criteria, a total of 183 patients   were evaluated. All the patients were evaluated clinically after admission. ECG, blood biochemistry and echocardiography were done. Patients were categorized into three groups according to the extent   of ST- segment depression.   Results: In this study, analysis of the baseline parameters revealed no statistically significant   difference among the three groups of patients (p>0.05). Mean sum of the ST-segment depression analysis was done and all mean values were more in group III patients. 41.0% patients developed  complications during the study period. Acute LVF (22.9%) was the most common complication   followed by arrhythmia (11.5%), cardiogenic shock (4.4%) and STEMI (2.2%). All the complications were more in group III patients. During this period 6% patients died and more death (12.3%) was observed in group III patients.   Conclusion: The amount of ST-segment depression is a powerful predictor of adverse in-hospital   outcome in patients with non ST-segment elevation acute coronary syndrome DOI: http://dx.doi.org/10.3329/cardio.v5i1.12275 Cardiovasc. j. 2012; 5(1): 62-66

Abstract:Background

Single-stranded (ss)RNA viruses are thought to evolve rapidly due to an inherently high mutation rate. However, it remains unclear how ssRNA viruses adapt to novel environments and/or how many and what types of substitutions are needed to facilitate this evolution. In this study, we followed the adaptation of the ssRNA bacteriophage Qβ using thermally adapted Escherichia coli as a host, which can efficiently grow at temperatures between 37.2 and 45.3 °C. This made it possible to evaluate Qβ adaptation to the highest known temperature that supports growth, 45.3 °C. We found that Qβ was capable of replication at this temperature; within 114 days (~1260 generations), we detected more than 34 novel point mutations in the genome of the thermally adapted Qβ population, representing 0.8% of the total Qβ genome. In addition, we returned the 45.3 °C-adapted Qβ populations to 37.2 °C and passaged them for 8 days (~124 generations). We found that the reverse-adapted Qβ population showed little to no decrease in fitness. These results indicate that Qβ can evolve in response to increasing temperatures in a short period of time with the accumulation of point mutations.

:Ceramic factory workers are potentially at risk to develop occupational respiratory diseases due to chronic inhalation of dust particles generated in the ceramic factory. A cross-sectional descriptive study was carried out to assess the respiratory and other health problems among the workers of Mirpur Ceramic Works Limited, Dhaka, Bangladesh during the period of April to June, 2011. Among 200 participants, 132 (66%) were males and 68 (34%) were females. Less than one-third of the workers were habituated to use personal protective equipments (PPE), while more than two-third were not habituated. Nearly half (45.5%) of the workers were suffering from at least one respiratory problem and of them 86.8% (P = 0.001) had problems after joining the factory. Of the respiratory sufferers 27% had chronic bronchitis, 20% bronchial asthma, 1% pulmonary tuberculosis, and 0.5% had silicosis. A significant numbers (60.5%) of workers were suffering from other health problems along with or without respiratory problems, in terms of musculoskeletal pain, back pain, headache, dermatitis, anaemia and fever. The prevalence of respiratory problems was significantly higher among non-users of PPE than PPE users (P = 0.006), and it was found to be higher with the increased of job duration. The study showed the notable higher prevalence of respiratory problems among the workers exposed to ceramic dust, although the other potential environmental confounding factors could not be ruled out in the analysis. Obligatory use of PPE by all workers and health education to increase awareness among the workers might have role to reduce the prevalence.

BackgroundFollowing the outbreak of the COVID-19 pandemic, the government of Bangladesh implemented strict non-therapeutic measures, i.e., “social distancing,” “lockdown,” “work from home,” in the first quarter of 2020. Like other professionals, teachers at schools, colleges and universities were confined within households. However, the introduction of online education imposed an additional burden on teachers along with growing household responsibilities, thus, affecting their psychological state.AimsThis study was aimed to explore the prevalence of mental health problems among teachers in Bangladesh and to identify the associated risk factors.MethodsThis web-based cross-sectional study was conducted during the second wave of COVID-19 pandemic in Bangladesh. Data were collected from 381 teachers working at schools, colleges, and universities between 01 August and 29 August 2021 by administering a self-reported e-questionnaire using Google Form, where the mental health of teachers was assessed by depression, anxiety, and stress scale. Data were analyzed using IBM SPSS Statistics (Version 26) and STATA Version 16, and multiple linear regression was executed to predict mental health problems among teachers.ResultsThe findings indicate that the overall prevalence of depression, anxiety, and stress among teachers was 35.4%, 43.7%, and 6.6%, respectively. The prevalence was higher among male and older teachers than among their female and younger colleagues. The findings further showed that place of residence, institution, self-reported health, usage of social and electronic media, and fear of COVID-19 significantly influenced the mental health status of teachers.ConclusionIt is strongly recommended that the government and policymakers provide proper mental health services to teachers in order to reduce mental health problems and thus sustain the quality of education during and after the pandemic.