Acinetobacter baumannii has been identified by the Infectious Diseases Society of America as one of the six pathogens that cause majority of hospital infections. Increased resistance of A. baumannii even to the latest generation of β-lactams like carbapenem is an immediate threat to mankind. As inner-membrane fraction plays a significant role in survival of A. baumannii, we investigated the inner-membrane fraction proteome of carbapenem-resistant strain of A. baumannii using Differential In-Gel Electrophoresis (DIGE) followed by DeCyder, Progenesis and LC-MS/MS analysis. We identified 19 over-expressed and 4 down-regulated proteins (fold change>2, p <0.05) in resistant strain as compared to reference strain. Some of the upregulated proteins in resistant strain and their association with carbapenem resistance in A. baumannii are: i) β-lactamases, AmpC and OXA-51: cleave and inactivate carbapenem ii) metabolic enzymes, ATP synthase, malate dehydrogenase and 2-oxoglutarate dehydrogenase: help in increased energy production for the survival and iii) elongation factor Tu and ribosomal proteins: help in the overall protein production. Further, entry of carbapenem perhaps is limited by controlled production of OmpW and low levels of surface antigen help to evade host defence mechanism in developing resistance in A. baumannii . Present results support a model for the importance of proteins of inner-membrane fraction and their synergistic effect in the mediation of resistance of A. baumannii to carbapenem.

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Comprehensive molecular characterization of DEC pathotypes, their incidence estimates, and antibiogram patterns will help in ascertaining better diagnostic and therapeutic measures in management of diarrheal diseases.

Diarrheal diseases are responsible for a significant proportion of mortality and morbidity all around the globe. The contribution of viruses to gastroenteritis incidences in humans is well established. In the present study, we have studied the prevalence of rotavirus, norovirus and enterovirus in Himachal Pradesh, a north Indian state. A total of 287 (111 children and 176 adults) stool samples of gastroenteritis patients were screened for the viruses using RT-PCR method. 34.5 % samples were positive for the viral pathogens of gastroenteritis. Rotavirus was the predominant virus detected in the study with 49.5 and 14.8 % positivity in children and adults, respectively. Enterovirus was present in 5.6 % cases whereas norovirus had least prevalence (1.4 %). Co infection (rotavirus and enterovirus) was witnessed at the prevalence rate of 0.6 %. Among different age groups, the prevalence of studied viruses was highest in the children belonging to the age groups of \5 years. Rotavirus infections were found to be significantly associated with vomiting and trend of higher rates of fever and dehydration was seen in children along with diarrhea. Seasonal distribution shows circulation of diarrheagenic viruses throughout the year. This is the first report of prevalence of various diarrheagenic viruses circulating in this region. The outcome of the study from this cohort provides a baseline data which can be used to design the preventive strategies in the otherwise unexplored state of Himachal Pradesh.

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Objectives: Nanoparticles synthesis via green approach is a scorching theme of research nowadays as it minimizes the use of harmful chemicals. Not much work has been done on bio reduction of copper salts; therefore our present work was focused on green synthesis of copper oxide nanoparticles using leaf extract of Callistemon viminalis. Methods: Bio reduction method was used for preparation of copper oxide nanoparticles using Callistemon viminalis leaf extract. Synthesis was carried out at three different temperatures namely 4ºC, room temperature and 60ºC. Results: Completion of reaction occurred at 60ºC and reduced copper oxide particles were further characterized by ultra violet spectroscopy, dynamic light scattering technique, fourier transform infrared spectroscopy, X-ray diffraction and photoluminescence spectroscopy. The antibacterial evaluation of nanoparticles was done against standard bacterial strains Acinetobacter baumannii and Escherichia coli. Synthesized copper oxide nanoparticles were found to exhibit antibacterial activity in both pathogenic strains. Conclusion: Overall we can conclude that bio reduction is facilitated at 60ºC and it is rapid, simple, inexpensive and effective way of producing antibacterial copper oxide nanoparticles.

Acinetobacter baumannii has emerged as one of the six most important drug-resistant microbes in the world. Resistance by A. baumannii to β-lactams and in particular to meropenem is a serious concern. In this connection, it is essential to understand the changes in the outer membrane proteome of A. baumannii in the initial stages of resistance. For this we have chosen one low resistant strain with minimal inhibitory concentration (MIC) of 32 μg/ml and one intermediate strain with very low MIC of 0.8 μg/ml of meropenem and compared their outer membrane profiles with that of sensitive strain, ATCC 19606 of A. baumannii. Decreased expression of porins, transporters and increased production of metabolic enzymes like Succinyl-CoA synthetase, enoyl-CoA hydratase is a common feature in both intermediate strain and low resistant strains. Interestingly, the differential protein expression levels showed a direct relationship with increasing meropenem resistance. It is clear that initial exposure to meropenem resistance drives A. baumannii to restrict the production of CarO and transporters, while the upregulation of genes of altered CarO, metabolic enzymes, peroxidines and antioxidant protein assist in the survival of the bacterium. Because of these unique features of adaptation combined with high metabolic changes in response to antibiotic pressure, A. baumannii poses challenges in therapeutic strategies