Expression of Four Methionine Sulfoxide Reductases in Staphylococcus aureus

Staphylococcus aureus possesses three MsrA enzymes (MsrA1, MsrA2, MsrA3) that reduce the S-epimer of methionine sulfoxide (MetO) and an MsrB enzyme that reduces R-MetO. The four msr genes are expressed from three different promoters. The msrA1/msrB genes are coexpressed. To determine the expression pattern of msr genes, three independent reporter strains were constructed where msr promoter was cloned in front of a promoterless lacZ and the resulting construct was integrated in the chromosome. Using these strains, it was determined that the msrA1/B expression is significantly higher in S. aureus compared to msrA2 or msrA3. Expression of msrA1/B was highest during stationary phase growth, but the expression of msrA2 and msrA3 was highest during the early to midexponential growth phase. Expression of msrA1/B was induced by oxacillin and the expression of msrA3 was upregulated by salt. Expression of msrA2 remained unchanged under all tested conditions

Slow Flow Past Porous Shell of Variable Permeability with Cavity at the Centre

In this paper slow flow of a viscous, incompressible fluid past a heterogeneous porous spherical shell with cavity is discussed. The permeability of porous sphere is varying with radial distance. Flow outside the porous spherical shell and inside the central cavity region is governed by the Stoke’s equation. Brinkman equation is used to analyze the flow inside the porous region. The boundary conditions used at the interface of porous and clear region are the continuity of velocity and stress. Exact solution of the problem is obtained and relevant quantities such as stream lines, velocity, pressure and drag on surface of the spherical shell are evaluated and exhibited graphically. The effect of various parameters on the flow has been discussed. Obtained results are useful for the flow past porous particles of variable permeability

Dynamic Relationship Study between the Observed Seismicity and Spatiotemporal Pattern of Lineament Changes in Palghar, North Maharashtra (India)

The Palghar region (north Maharashtra, India), located in the northwestern part of the stable continental region of India, experienced a low magnitude earthquake swarm, which was initiated in September 2018 and is continuing to date (as of October 2021). From December 2018 to December 2020, ~5000 earthquakes with magnitudes from M1.2 to M3.8 occurred in a small region of 20 × 10 km2. These earthquakes were probably triggered by fluid migration during seasonal rainfall. In this study, we have used multi-temporal Landsat satellite data of the year 2000, 2015, 2018, 2019, and 2020, extracted lineaments, and studied the changes in frequency and pattern of lineaments before and after the initiation of the swarm in the Palghar region. An increase in the lineament density and amount of rainfall are found to be associated with the increasing frequency of earthquakes

Epstein Barr virus induced pneumonitis: a rare entity in immunocompetent baby

Acute infectious interstitial pneumonitis (IP) (Epstein Barr virus (EBV)-associated IP) in children has been most commonly associated with human immunodeficiency virus (HIV) infection and immunocompromised hosts. Here we report a case of EBV-associated interstitial pneumonitis with cervical lymphadenopathy in an immunocompetent child. Patient underwent extensive routine and serologic workup which revealed positive polymerase chain reaction (PCR) for EBV, pointing towards the diagnosis of EBV induced pneumonitis. It is a very rare entity and is hardly seen among immunocompetent individuals especially young children. The aim of this case report is to bring to our notice that among all described pneumonias, EBV induced pneumonitis can be a possibility while dealing with lung infections

Temporal variations in ⁸⁷Sr/⁸⁶Sr and ε_Nd in sediments of the southeastern Arabian Sea: impact of monsoon and surface water circulation

Sr and Nd isotopic composition of silicate fractions of sediments have been measured in two well dated gravity cores from the eastern Arabian Sea archiving a depositional history of ∼29 and ∼40 ka. The 87Sr/86Sr and εNd in the northern core (SS-3104G; 12.8°N, 71.7°E) ranges from 0.71416 to 0.71840 and −8.8 to −12.8; these variations are limited compared to those in the southeastern core (SS-3101G; 6.0°N, 74.0°E), in which they vary from 0.71412 to 0.72069 and −9.0 to −15.2 respectively. This suggests that the variation in the relative proportions of sediments supplied from different sources to the core SS-3104G are limited compared to core SS-3101G. The 87Sr/86Sr and εNd profiles of SS-3101G exhibit two major excursions, ca. 9 ka and 20 ka, coinciding with periods of Holocene Intensified Monsoon Phase (IMP) and the Last Glacial Maximum (LGM) respectively with more radiogenic 87Sr/86Sr and lower εNd during these periods. These excursions have been explained in terms of changes in the erosion patterns in the source regions and surface circulation of the Northern Indian Ocean resulting from monsoon intensity variations. The intensification of North-East (NE) monsoon and associated strengthening of the East Indian Coastal Current in southwest direction during LGM transported sediments with higher 87Sr/86Sr and lower εNd from the western Bay of Bengal to the Arabian Sea. In contrast, enhanced South-West (SW) monsoon at ∼9 ka facilitated the transport of sediments from the northern Arabian Sea, particularly Indus derived, to the southeastern Arabian Sea. This study thus highlights the impact of monsoon variability on erosion patterns and ocean surface currents on the dispersal of sediments in determining the Sr and Nd isotopic composition of sediments deposited in the eastern Arabian Sea during the last ∼40 ka

Upotreba bezstanične matrice iz ošita bivola pri pupčanoj hernioplastici svinja.

Acellularization of xenogenic biomaterials has been highly desired for implantation without considerable adverse inflammatory and immune responses. Therefore, the present study was undertaken to acellularize the diaphragm of buffalo origin and to evaluate the effi cacy of this prepared acellular diaphragm matrix (ADM) scaffolds for the repair of umbilical hernia in pigs. Buffalo diaphragms were acellularized with different concentrations of sodium deoxycholate over a range of periods. Produced ADM scaffolds were used during umbilical hernioplasty in 12 crossbred Landrace pigs. Harvested serum samples on post-implantation days (0, 15 and 30) were subjected to sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) to observe serum protein distribution pattern. Treatment with 2 % sodium deoxycholate lead to complete acellularization of the bubaline diaphragm at 48 h. Microscopic examination of the detergent treated matrix confirmed complete extraction of stromal cells and orderly arranged collagen fibres. All the hernias repaired with ADM remained sound over a period of 3 months. The serum protein distribution on post-implantation day 15 was found different from day zero and becomes normal on day 30. All the hernias implanted with ADM healed completely without graft rejections. The present study suggested that 2 % sodium deoxycholate can be used for complete acellularization of bubaline diaphragm, and produced ADM may be used safely for umbilical hernioplasty in pigs.Bezstanična struktura ksenogenih biomaterijala smatra se povoljnom jer pri implantaciji ne uzrokuje upalne i imunološke reakcije. U ovom je istraživanju proveden postupak dobivanja bezstanične matrice iz ošita (BMO) bivola koji je zatim bio rabljen kao podloga za obnavljanje tkiva pri operaciji pupčane hernije svinja. Gubitak stanične strukture bivoljih ošita proveden je uz pomoć različitih koncentracija natrijeva deoksikolata, primijenjenih u određenim vremenskim razmacima. Proizvedene bezstanične matrice ošita upotrijebljene su pri pupčanoj hernioplastici kod 12 svinja križanaca landras pasmine. Uzorci seruma, prikupljeni 0., 15. i 30. dana nakon implantacije, bili su podvrgnuti natrijev dodecil sulfat-poliakrilamid gel elektroforezi (SDS-PAGE) s ciljem promatranja razdiobe serumskih proteina. Obrada 2 %-tnim natrijevim deoksikolatom dovela je do potpunog gubitka stanične strukture bivoljeg ošita za 48 sati. Mikroskopskim pregledom matrice obrađene detergentom potvrđeno je potpuno uklanjanje stanica strome te uredno raspoređena kolagena vlakna. Mjesta operacije svih hernija kod kojih je upotrijebljena bezstanična matrica ošita ostala su zdrava tijekom 3 mjeseca. Razdioba serumskih proteina 15 dana nakon implantacije bila je različita u odnosu na početni (0.) dan, a 30. dan nakon implantacije vratila se na normalu. Sve hernije operirane uz upotrebu BMO u potpunosti su zacijelile bez odbacivanja presatka. Pomoću 2 % natrijeva deoksikolata postiže se potpuni gubitak stanične strukture bivoljeg ošita koji se može sigurno primijeniti pri pupčanoj hernioplastici svinja

Effect of zoledronic acid on functional outcome in cases of pertrochanteric femoral fractures in elderly patients operated with proximal femoral nailing

Background: Osteoporosis is a very common problem in geriatric population and postmenopausal women. Zoledronic acid injection is a very convenient and effective treatment option available for osteoporosis. Our study aimed to study the effect of zoledronic acid on functional outcome and fracture related complications in elderly patients with low energy pertrochanteric femoral fractures who were operated with proximal femoral nail. Methods: This was a case control study. Elderly patients who underwent surgery in the form of proximal femoral nailing for low energy pertrochanteric femoral fractures were included. Injection zoledronic acid was given to every alternate patient who underwent surgery. Radiological healing was evaluated at six weekly intervals for six months and then 12 weekly intervals for one year. The Harris hip score was used to measure the functional outcome of the patient. Results: Effective study population consisted of total 49 patients (25 cases and 24 controls). The mean union time in the cases and the control was 8.76±9.12 weeks and 7.04±1.57 weeks respectively. The mean Harris hip score was 86.742±7.55 in the cases and 84.339±11.20 in the control group. The p value was 0.3815. This study concluded that the two groups had no statistically significant difference between functional outcome and fracture related complications. Conclusions: Zoledronic acid in patients admitted for surgery with osteoporotic fracture does not improve the functional outcome of the patients. It does not affect the mortality of the patients

Significance of Four Methionine Sulfoxide Reductases in Staphylococcus aureus

Staphylococcus aureus is a major human pathogen and emergence of antibiotic resistance in clinical staphylococcal isolates raises concerns about our ability to control these infections. Cell wall-active antibiotics cause elevated synthesis of methionine sulfoxide reductases (Msrs: MsrA1 and MsrB) in S. aureus. MsrA and MsrB enzymes reduce S-epimers and R-epimers of methionine sulfoxide, respectively, that are generated under oxidative stress. In the S. aureus chromosome, there are three msrA genes (msrA1, msrA2 and msrA3) and one msrB gene. To understand the precise physiological roles of Msr proteins in S. aureus, mutations in msrA1, msrA2 and msrA3 and msrB genes were created by site-directed mutagenesis. These mutants were combined to create a triple msrA (msrA1, msrA2 and msrA3) and a quadruple msrAB (msrA1, msrA2, msrA3, msrB) mutant. These mutants were used to determine the roles of Msr proteins in staphylococcal growth, antibiotic resistance, adherence to human lung epithelial cells, pigment production, and survival in mice relative to the wild-type strains. MsrA1-deficient strains were sensitive to oxidative stress conditions, less pigmented and less adherent to human lung epithelial cells, and showed reduced survival in mouse tissues. In contrast, MsrB-deficient strains were resistant to oxidants and were highly pigmented. Lack of MsrA2 and MsrA3 caused no apparent growth defect in S. aureus. In complementation experiments with the triple and quadruple mutants, it was MsrA1 and not MsrB that was determined to be critical for adherence and phagocytic resistance of S. aureus. Overall, the data suggests that MsrA1 may be an important virulence factor and MsrB probably plays a balancing act to counter the effect of MsrA1 in S. aureus.This work was supported in part by a Warner/Fermaturo grant and A.T. Still University Board of Trustees Research Funds, by grant 1R15AI090680-01 from the National Institutes of Health to VKS, and grants from the Kirksville College of Osteopathic Medicine Biomedical Sciences Graduate Program to TRJ and KRB. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript