122 research outputs found
Molecular docking simulation studies on potent butyrylcholinesterase inhibitors obtained from microbial transformation of dihydrotestosterone
BACKGROUND: Biotransformation is an effective technique for the synthesis of libraries of bioactive compounds. Current study on microbial transformation of dihydrotestosterone (DHT) (1) was carried out to produce various functionalized metabolites. RESULTS: Microbial transformation of DHT (1) by using two fungal cultures resulted in potent butyrylcholinesterase (BChE) inhibitors. Biotransformation with Macrophomina phaseolina led to the formation of two known products, 5α-androstan-3β,17β-diol (2), and 5β-androstan-3α,17β-diol (3), while biotransformation with Gibberella fujikuroi yielded six known metabolites, 11α,17β-dihydroxyandrost-4-en-3-one (4), androst-1,4-dien-3,17-dione (5), 11α-hydroxyandrost-4-en-3,17-dione (6), 11α-hydroxyandrost-1,4-dien-3,17-dione (7), 12β-hydroxyandrost-1,4-dien-3,17-dione (8), and 16α-hydroxyandrost-1,4-dien-3,17-dione (9). Metabolites 2 and 3 were found to be inactive, while metabolite 4 only weakly inhibited the enzyme. Metabolites 5–7 were identified as significant inhibitors of BChE. Furthermore, predicted results from docking simulation studies were in complete agreement with experimental data. Theoretical results were found to be helpful in explaining the possible mode of action of these newly discovered potent BChE inhibitors. Compounds 8 and 9 were not evaluated for enzyme inhibition activity both in vitro and in silico, due to lack of sufficient quantities. CONCLUSION: Biotransformation of DHT (1) with two fungal cultures produced eight known metabolites. Metabolites 5–7 effectively inhibited the BChE activity. Cholinesterase inhibition is among the key strategies in the management of Alzheimer’s disease (AD). The experimental findings were further validated by in silico inhibition studies and possible modes of action were deduced
Outcome of Retinaculotomy for Carpal Tunnel Syndrome
Objective: To evaluate the results of a minimally invasive technique performed for the most prevalent diseasewhich is not dependent on sophisticated instrumentation and results in early return to work.Material and Methods: A total of 52 patients was operated and included in the study. The record of thesepatients was collected on specified proforma.We used the retinaculotomy method performed by 3 surgeons of the same competence level.Results: Total number of patients operated was 52 Male 8 (15%) Female 44 (85%). A total of 48 (92%) patientsimproved (by 4th week in terms of VAS from 6 to 1 or 0). 9% of patients had scar tenderness which improved by 4th week in 100 % patients. Almost all the patients resumed their daily life activities by 4th week.Conclusion: It was concluded from this study that using the mini technique of retinaculotomy the complicationsassociated with the use of the classic open technique can be avoided and patients successfully treated can have an early return to their normal daily life activities
Hemoptysis secondary to rupture of infected aortic aneurysm- a case report
BACKGROUND: Massive hemoptysis is a life-threatening condition and can arise as a complication of various conditions. It rarely occurs as a complication of a ruptured thoracic aortic aneurysm. Even rarer are conditions where pseudoanurysms of aorta result due to infection. CASE PRESENTATION: A 30 year-old female patient presented with left sided chest pain, intermittent fever, cough and massive hemoptysis. A pseudo-aneurysm of proximal descending thoracic aorta at the level of the left Subclavian artery was noted over CT scan. Upon performing a left posterolateral thoracotomy, the aneurysm was seen to have ruptured into the apical segment of left upper lobe, contained mainly by a thrombus. The anterior wall of the pseudoaneurysm was debrided and a bovine pericardial patch was used to repair the aortic defect. Cultures of the tissue obtained showed Enterobacter species, therefore the patient was prescribed 6 weeks of IV antibiotics following surgery. Post-operative CT scan revealed reduced diameter of the aorta. She was discharged in good health and remains well at follow up evaluation. CONCLUSIONS: We present a case of hemoptysis caused by a ruptured descending aorta aneurysm into left lung. The aneurysm was secondary to infection by Enterobacter. Surgical repair of the concerned region of aorta was effective, without any major sequelae. To the best of our knowledge, no such cases have been reported previousl
Tropospheric NO 2
The focus of this study is to assess spatiotemporal variability of tropospheric NO2 over South Asia using data from spaceborne OMI during the past decade (2004–2015). We find an average value of NO2 1.0 ± 0.05 × 1015 molec/cm2 and a significant decadal increase of 14%. The elevating NO2 pollution over the region is linked to rise in motor vehicles and industrial and agricultural activities and increase in biomass fuel usage. The observed seasonality of NO2 is associated with change in meteorological conditions and seasonal cycles of anthropogenic emissions. OMI data reveal a seasonal peak in spring followed by winter largely linked to metrological conditions and anthropogenic emissions from crop residue and biomass burning for heating purpose, and low concentration in summer is mostly attributed to meteorological conditions. Significant increase, up to 42%, in NO2 concentrations over northwestern IGB, is observed connected to large scale postmonsoon crop residue events of 2010 and 2012. It is seen that NO2 is mounting over all the hotspot locations and most of the cities. Dhaka shows the highest increase of 77% followed by Islamabad (69%), Kabul (68%), Korba (64%), Bardhaman (47%), and Lahore (40%). On the contrary, DG Khan has shown negative trend of −11%
Minimization of total harmonic distortions of cascaded H-bridge multilevel inverter by utilizing bio inspired AI algorithm
Minimizing total harmonic distortion (THD) with less system complexity and computation time is a stringent constraint for many power systems. The multilevel inverter can have low THD when switching angles are selected at the fundamental frequency. For low-order harmonic minimization, selective harmonic elimination (SHE) is the most adopted and proficient technique but it involves the non-linear transcendental equations which are very difficult to solve analytically and numerically. This paper proposes a genetic algorithm (GA)-based optimization technique to minimize the THD of cascaded H-bridge multilevel inverter. The GA is the finest approach for solving such complex equations by obtaining optimized switching angles. The switching angles are calculated by the genetic algorithm by solving the nonlinear transcendental equations. This paper has modeled and simulated a five-level inverter in MATLAB Simulink. The THD comparison is carried out between step modulation method and optimization method. The results reveal that THD has been reduced from 17.88 to 16.74% while third and fifth harmonics have been reduced from 3.24%, 3.7% to 0.84% and 3.3%, respectively. The optimization method along with LC filter significantly improves the power quality providing a complete sinusoidal signal for varying load
Counter electrode materials based on carbon nanotubes for dye-sensitized solar cells
Efficiency, stability, and cost-effectiveness are the prime challenges in research of materials for solar cells. Technologically as well as scientifically, attention gained by dye-sensitized solar cells (DSSCs) stems from their low material and fabrication costs as well as high efficiency projections. The aim of this study is to explore the carbon nanotubes (CNTs) based counter electrode (CE) materials for DSSCs and to reconnoiter the suitable alternative materials in place of noble metals such as Platinum (Pt), and Gold (Au).. Various classes of CE materials based on CNTs including pure single walled, double walled, and multiwalled CNTs, doped CNTs and their hybrid composites with various polymers, and transition metal compounds are discussed comprehensively in light of the research work started since the inspection of DSSCs and CNTs.The properties associated with such materials, including surface morphology, structural determination, thermal stability, and electrochemical activity, are also thoroughly analyzed and compared. This work provides a thorough insight into the possibility of exploiting CNTs as alternative CE materials. In addition to the above, this study also includes the working and brief overview of materials for other components of DSSCs such as photoanode, electrolyte, and sensitizer.
A review of toolkits and case definitions for detecting enteric fever outbreaks in Asian and African countries from 1965-2019
Background: This review assessed the case definitions, diagnostic criteria, antimicrobial resistance, and methods used for enteric fever outbreaks and utilization of any unified outbreak score or checklist for early identification and response in Asia and Africa from 1965-2019.Methods: We searched enteric fever outbreaks using PubMed, Google Scholar, and the Cochrane library. Studies describing a single outbreak event of enteric fever in Asia and Africa from 1965-2019 were reviewed. We excluded case reports, letter to editors, studies reporting typhoid in conjunction with other diseases, the Centers for Disease Control and Prevention (CDC) trip reports, the World Health Organization (WHO) bulletins report, data from mathematical modeling and simulation studies, reviews and ProMed alert. Also, non-typhoidal salmonella outbreaks were excluded.Results: A total of 5063 articles were identified using the key terms and 68 studies were selected for data extraction. Most (48, 71%) outbreaks were from Asian countries, 20 (29%) were reported from Africa. Only 15 studies reported the case definition used for case identification during an outbreak and 8 of those were from Asia. A third (20, 29%) of the studies described antibiotic resistance pattern. 43 (63%) studies contained information regarding the source of the outbreak. Outcomes (hospitalization and deaths) were reported in a quarter of studies. Only 23 (29%) of the studies reported outbreak control strategies while none reported any unified outbreak score or a checklist to identify the outbreak.Conclusion: This review highlights the variability in detection and reporting methods for enteric fever outbreaks in Asia and Africa. No standardized case definitions or laboratory methods were reported. Only a few studies reported strategies for outbreak control. There is a need for the development of a unified outbreak score or a checklist to identify and report enteric fever outbreaks globally
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