Role of Disulfide Bond Rearrangement in Newcastle Disease Virus Entry: A Dissertation

Newcastle disease virus (NDV), an avian paramyxovirus, enters the host cell by fusion of viral and host cell membranes. The fusion of two membranes is mediated by the viral fusion (F) protein. The F protein, like other class I fusion proteins, is thought to undergo major conformational changes during the fusion process. The exact mechanism that leads to major refolding of F protein is not clear. Recently, it has been proposed that disulfide bond reduction in the fusion protein of some viruses may be involved in the conformational changes in fusion proteins. In some viruses, the reduction of disulfide bonds in the fusion protein is mediated by host cell disulfide isomerases belonging to the protein disulfide isomerase (PDI) family. In this study, the role of disulfide bond isomerization in the entry of NDV was analyzed. Using inhibitors of thiol-disulfide isomerases, we found that blocking the reduction of disulfide bonds in the fusion protein inhibited cell-cell fusion as well as virus entry into the host cell. Also, over-expression of isomerases belonging to the PDI family significantly enhanced cell-cell fusion. Taken together, these results suggest that free thiols play an important role in fusion mediated by NDV glycoproteins. Using a thiol specific, membrane impermeable biotin, MPB, we found that free thiols are produced in cell surface-expressed NDV F protein. The production of free thiols was inhibited by inhibitors of thiol-disulfide isomerases. Over-expression of isomerases belonging to the PDI family enhanced detection of free thiols in F protein. In F protein, present in virions or in virus-like particles, free thiols were detected only after the particles were attached to target cells. Taken together, these results suggest that free thiols are produced in F protein and the production of free thiols is mediated by host cell thiol-disulfide isomerases. Using conformation sensitive antibodies, we also studied the conformation of cell surface-expressed F protein in the presence ofthiol-disulfide isomerase inhibitors or in cells over-expressing thiol-disulfide isomerases. In the presence of thiol-disulfide isomerase inhibitors, the cell surface-expressed F protein was in a prefusion conformation while in cells over-expressing thiol-disulfide isomerases the F protein was in a post-fusion conformation. We also correlated the production of free thiols to the conformational changes in F protein. Using temperature-arrested intermediates or F protein with mutations in heptad repeat domains, which are defective in attaining intermediate conformations, we found that free thiols are produced before any of the proposed conformational changes in F protein. Also, the production of free thiols in F protein was found to be independent of its activation by hemagglutinin-neuraminidase (HN) protein. These results suggest that free thiols are probably required for the activation of F protein during membrane fusion

Gendered Portrayals of Domestic Work in Indian Television

Despite the entry of women into the labour force in India, women still participate in paid employment at a low rate; the rate even fell recently from 31% to 24% (ILO, 2013). This represents an alarming need for change in gender roles. The present article focuses on how electronic media content portrays men’s and women’s roles in performing housework. In a study of 30 TV serials that aired from 1990-2016 and 14 old and new TV advertisements, the findings show that mostly women are depicted doing domestic work. Media demonstrates gender disparities between men and women in performing domestic work, which is keeping our society from achieving gender equality. There is a need to reconsider men’s and women’s roles in the family. So, this study suggests that media content should not show biased gender roles. To avoid gender inequality at the micro level, we need to disseminate idealistic content to our nation’s audience. To ensure women’s participation in the work force, men’s involvement in domestic chores needs to be increased; this can also improve the gross domestic productivity of the country

Demographic profile and risk factors associated with dry eye disease in North Western Rajasthan, India

Background: The aim was to study the demographic profile and analyze risk factor associated with dry eye disease in North West Rajasthan, India.Methods: This was a hospital-based study conducted in Department of Ophthalmology, Sardar Patel Medical College, Bikaner, Rajasthan. Sample size of this study was 100 patients. All participants underwent a general ophthalmic assessment including history of any previous ocular and systemic illness along with ocular examination on slit lamp and specific tests for dry eye (Schirmer's test and Tear film break up time) were performed.Results: Dry eye were seen maximum in age group 46 to 60 years (41%), followed by 61-75 years (23%). Female’s preponderance was seen compared with male. Dry eye patients belong from rural areas were (57%) while remaining (43%) from urban areas and among these highest were farmer/labourers (32%). Several known risk factors were found in this study which include post-menopause. Climatic condition like excessive wind, high temperature and computers users had strong association with dry eye. In Systemic disease rheumatoid arthritis was commonly associated with dry eye were. Smoking contact lens use were also associated with increased risk of developing dry eye.Conclusions: Dry eye disease are more common in older age group patients. Female’s preponderance were found in the study especially postmeopausal women. Dry eye disease are more common in patients belongs to rural areas. Risk factor associated with dry eye were Climatic condition like excessive wind, high temperature and computers users, systemic disease like rheumatoid arthritis Smoking, contact lens users

COVID-19: Emerging Challenges for Students in Medicine and Schools in the United States

The coronavirus pandemic has changed the world everywhere, including the lives of high schoolers in America. The sudden sharp rise in coronavirus cases forced the closure of schools in Mid-March to curb the further spread of the virus. Several end-of-the-year celebrations, school activities, and examinations were canceled. At the same time, the cancellations gave a chance for the youth to adapt to uncertain situations and learn adifferent perspective of life. Living in Florida, a state that battles hurricanes for almost half a year, school closures have become the norm: it is not rare for students to be reminded to keep their textbooks and notes home for a week or two. Prepared from past closures due to hurricanes, the school district board already had a virtual school platform, and the principal instructed all students to shift to Zoom and alternative eLearning. However, when the coronavirus pandemic led to the indefinite closure of high schools across the country, thiswas something new, different, and unexpected that school communities had to face

Cost-effectiveness of Training Programmes in Insurance Sector of India

In the present era of globalization, trough competition and advancement of information technology, the paradigm for success has shifted towards intellectual assets. New ways of commerce and management structures are required to effectively exploit intellectual assets foremost to an improved approach on the development of human capital. Training requires substantial allocation of monetary, human and time resources. A systematic evaluation of training programs is the call of the time. The insurance sector has been playing a vital role in the process of economic advancement since independence in India. The objective of the present study is to identify the cost-effectiveness of training programs in the insurance sector in India. A sample of four companies has been randomly selected. This study is descriptive in nature. Secondary data has been analysed. Effectiveness-cost ratios were calculated and inferences have been drawn accordingly. Finding suggests that training programs in public insurance sector is more cost-effective as compared to private insurance sector in India

FORMULATION AND EVALUATION OF HERBAL GEL FOR WOUND HEALING

The aim of the present investigation was to formulate and evaluate the herbal gel containing honey and curcumin for wound healing and antimicrobial potential. Curcumin and honey used in the preparation possess an excellent anti-inflammatory, antioxidant and healing potential. Gelling agent used in this study was Carbopol 934P. In the present study five formulations containing different concentration of carbopol and honey were formulated and optimized. The optimized formulations were selected for further studies. Optimized gel was then loaded with active drug. The formulations were characterized for initial physicochemical parameters i.e. surface pH, spreadability, viscosity and antimicrobial susceptibility test to observe toxicity or side effects. The result revealed that the surface pH was within the range of skin pH. The viscosity and spreadability of the gel was appropriate and zone of inhibition was also satisfactory for optimized formulations G4 and G5. The preparations were stable under normal storage conditions and did not produce any skin irritation, i.e., erythema and oedema for about a month, when applied over the skin