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11.
Stephanie M. Lim Aaron C. Brault Geert van Amerongen Angela M. Bosco-Lauth Hannah Romo Varsha D. Sewbalaksing Richard A. Bowen Albert D.M.E. Osterhaus Penelope Koraka Byron E.E. Martina 《Emerging infectious diseases》2015,21(8):1357-1365
West Nile virus (WNV) outbreaks in North America have been characterized by substantial die-offs of American crows (Corvus brachyrhynchos). In contrast, a low incidence of bird deaths has been observed during WNV epidemic activity in Europe. To examine the susceptibility of the western European counterpart of American crows, we inoculated carrion crows (Corvus corone) with WNV strains isolated in Greece (Gr-10), Italy (FIN and Ita09), and Hungary (578/10) and with the highly virulent North American genotype strain (NY99). We also inoculated American crows with a selection of these strains to examine the strains’ virulence in a highly susceptible bird species. Infection with all strains, except WNV FIN, resulted in high rates of death and high-level viremia in both bird species and virus dissemination to several organs. These results suggest that carrion crows are highly susceptible to WNV and may potentially be useful as part of dead bird surveillance for early warning of WNV activity in Europe. 相似文献
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Sydney Wendt Zainub Abdullah Spencer Barrett Cyrus Daruwalla Jonathan A. Go Brandon Le Elijah Li Chelsea Livingston Matthew Miller Lauren Nakhleh Joseph Pecha Shravya Pothula Swetak Pradhan Varsha Sathappan Alay Shah Alan-Michael Sonuyi Peter Ugoh Qiancheng Wang Andrew G. Lee 《Survey of ophthalmology》2021,66(2):354-361
The coronavirus (COVID-19) pandemic temporarily suspended medical student involvement in clinical rotations, resulting in the need to develop virtual clinical experiences. The cancellation of clinical ophthalmology electives and away rotations reduces opportunities for exposure to the field, to network with faculty, conduct research, and prepare for residency applications. We review the literature and discuss the impact and consequences of COVID-19 on undergraduate medical education with an emphasis on ophthalmic undergraduate medical education. We also discuss innovative learning modalities used from medical schools around the world during the COVID-19 pandemic such as virtual didactics, online cases, and telehealth. Finally, we describe a novel, virtual neuro-ophthalmology elective created to educate medical students on neuro-ophthalmology foundational principles, provide research and presentation opportunities, and build relationships with faculty members. These innovative approaches represent a step forward in further improving medical education in ophthalmology during COVID-19 pandemic and beyond. 相似文献
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Gurpreet Kaur Varsha Dogra Rajeev Kumar Sandeep Kumar Gaurav Bhanjana Neeraj Dilbaghi Nitin Kumar Singhal 《International journal of pharmaceutics》2018,535(1-2):95-105
In the present study, we have synthesized mixed cuprous/copper oxide nanosuspensions by metallosurfactant based microemulsion technique. Three metallosurfactants were synthesized which includes two non-ionic double chained metallosurfactants with C12, C16 chains with coordinated copper i.e. Cudda and Cuhexa, respectively. Another cationic double chained metallosurfactant with loosely bound metal (Cuctac) was also prepared. The prepared metallocomplexes were characterized using FTIR, elemental analysis, and NMR. The effect of the position of metallosurfactant in microemulsion on the fabrication and properties of nanosuspensions was elucidated. In this method, no external reducing agent and capping agent were added and tween 80 acted both as reducing and stabilizing agent for the nanoparticles. The synthesized nanoparticles were characterized and it was observed that mixed copper and cuprous oxide particles are present in colloidal suspension for all the three studied metallosurfactants. The kinetics of formation of mixed copper/cuprous oxide nanosuspensions (Ns) and their stability was estimated using Uv-visible spectroscopy. Further, the binding and interactions of copper nanosuspensions with calf Thymus DNA (CT-DNA) were assessed using Uv–vis spectroscopy, circular dichroism and gel electrophoresis. Additionally, the antioxidant activity of the Cu Ns was checked using DPPH assay. The role of positive charge on nanoparticles as evaluated from Zeta potential was responsible for DNA affinity. The DNA conformational changes in the presence of nanosuspensions and relevant scavengers were investigated. Further, the anti-proliferative activity of copper Ns was assessed using HeLa cells and Cuhexa derived Ns were proved to be active with highest activity at a low concentration and were nontoxic towards normal cell lines. In summary, this work demonstrates a softer approach for the synthesis of copper nanosuspensions with a size range of 2–5?nm and evaluated the role of type and structure of metallosurfactant on size, stability of particles and anti-proliferative activity. 相似文献
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BACKGROUND AND AIMS: Non-response to interferon (IFN) monotherapy is a major therapeutic problem in the management of chronic hepatitis B infection. The efficacy of combination therapy to enhance the immunomodulatory effect of IFN by combining granulocyte-macrophage colony-stimulating factor (GMCSF) or decreasing viral load by adding an antiviral agent such as lamivudine was evaluated prospectively. METHODS: Twenty-four patients with chronic hepatitis B who were non-responders to previous IFN therapy were randomized to receive an IFN and GMCSF (group A, n = 10) or IFN and lamivudine (group B, n = 14) combination for 6 months. The end-of-treatment response was assessed by hepatitis B virus (HBV)-DNA and hepatitis B e antigen (HBeAg) determination. RESULTS: All patients successfully completed both the treatment schedules. The mean age, alanine aminotransferase (ALT) levels, liver histology, HBV-DNA levels and distribution of HBV genotypes were comparable between the two groups. At the end of treatment there was a significant decrease in mean ALT levels. The HBV-DNA and HBeAg loss was seen in six of 10 (60%) patients in group A and in seven of 14 (50%) patients in group B. During a mean follow-up of 15 +/- 3 months, two of six (33%) patients in group A and three of seven (43%) patients in group B relapsed with HBV-DNA and HBeAg positivity, which meant an overall sustained response of 40% and 28%, respectively. None of the factors such as HBV viral load, ALT levels or liver histology could predict the non-response to combination therapy or occurrence of relapse. There was a trend in patients with genotype A compared with genotype D towards non-response to therapy, although the difference was not significant. CONCLUSIONS: The combination of IFN plus GMCSF or lamivudine was effective in non-responders to IFN monotherapy. Larger studies using such combination therapies would be helpful in improving treatment strategies for chronic hepatitis B. 相似文献
18.
Varsha M. Thomas Ryan M. Brown Deborah S. Ashcraft George A. Pankey 《International journal of antimicrobial agents》2019,53(5):663-668
Acinetobacter baumannii is an opportunistic pathogen predominantly associated with nosocomial infections. The World Health Organization's data on antibiotic-resistant ‘priority pathogens’ reports carbapenem-resistant A. baumannii as a pathogen which is in critical need of research and development of new antimicrobials. Emerging resistance against polymyxins, last-resort drugs for carbapenem-resistant A. baumannii, increases the need for new therapeutic approaches such as synergistic combinations. Nisin, an antibacterial peptide produced by the Gram-positive bacteria L. lactis, is a US Food and Drug Administration approved food preservative with bactericidal action predominantly against other Gram-positive bacteria. A 2008 study reported that topical nisin was effective against staphylococcal mastitis in humans. Additionally, nisin has shown activity against Gram-negative bacteria in combination with antimicrobials such as polymyxin B. A recent in vitro study reported that nisin and polymyxin B exhibited synergistic activity against one isolate each of A. baumannii, Acinetobacter lwoffii and Acinetobacter calcoaceticus using time-kill assay and checkerboard technique. We evaluated the synergistic potential of nisin and polymyxin B against 15 unique clinical A. baumannii isolates using time-kill assay. Three of eight (38%) extensively drug-resistant and six of seven (86%) pandrug-resistant A. baumannii isolates showed synergy with one or more combinations of nisin and polymyxin B. The synergy seen with the use of lower concentrations of polymyxin B may help in reducing the dose-dependent side effects. Additional studies involving pharmacokinetics and pharmacodynamics of nisin are required to explore clinical possibilities. 相似文献
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Neeraj Aggarwal Varsha Potdar Neetu Vijay Labanya Mukhopadhyay Biswajyoti Borkakoty S. Manjusree Manohar Lal Choudhary Deepika Chowdhury Riya Verma Sumit Dutt Bhardwaj Neelanjana Sarmah Sreelatha K. H. Prabhat Kumar Nivedita Gupta 《Viruses》2022,14(3)
SARS-CoV-2/influenza virus co-infection studies have focused on hospitalized patients who usually had grave sequelae. Here, we report SARS-CoV-2/influenza virus co-infection cases from both community and hospital settings reported through integrated ILI/SARI (Influenza Like Illness/Severe Acute Respiratory Infection) sentinel surveillance established by the Indian Council of Medical Research. We describe the disease progression and outcomes in these cases. Out of 13,467 samples tested from 4 July 2021–31 January 2022, only 5 (0.04%) were of SARS-CoV-2/influenza virus co-infection from 3 different sites in distinct geographic regions. Of these, three patients with extremes of age required hospital admission, but none required ICU admission or mechanical ventilation. No mortality was reported. The other two co-infection cases from community settings were managed at home. This is the first report on SARS-CoV-2/Influenza virus co-infection from community as well as hospital settings in India and shows that influenza viruses are circulating in the community even during COVID-19. The results emphasize the need for continuous surveillance for multiple respiratory pathogens for effective public health management of ILI/SARI cases in line with the WHO (World Health Organization) recommendations. 相似文献