Učinkovitost zatvaranja sisnih kanala kao prevencija novih intramamarnih infekcija u mliječnih krava tijekom suhostaja

The aim of our study was to evaluate the effect of an internal teat sealant infused upon drying off on the incidence of new intra-mammary infections (IMI) during the dry period in dairy cattle. Due to the non-availability of the product on the Indian market, the product was prepared in a laboratory using bismuth subnitrate and liquid paraffin. A total of 64 quarters free from infection on culture were selected for the study at 60 days before the expected date of parturition. The quarters were randomly divided into two groups (group A and group B), with 32 quarters in each group. The group A quarters were infused with teat sealant at the time of drying off, and the quarters in group B were kept as the control and no treatment was provided to them. Milk samples from all the selected quarters were subjected to cultural examination at the time of drying off and 1-3 days post calving. The incidence of new IMI’s between drying off and calving was significantly lower for group A quarters when compared to group B quarters (12.5% vs 34.4%). The incidence of new IMI’s in group A and group B quarters was significantly lower for Streptococcus uberis (3.13% vs 18.75%) and Streptococcus dysgalactiae (3.13% vs 12.5%). The study concluded that infusion of teat sealant at drying off is helpful in lowering the incidence of new IMI’s during the dry period.Cilj ovog istraživanja bio je procijeniti učinak zatvaranja sisnih kanala na incidenciju infekcija vimena (IMI) mliječnih krava za vrijeme suhostaja. Zbog nedostupnosti komercijalnih preparata na indijskom tržištu, proizvod za zatvaranje sisnih kanala je pripravljen u laboratoriju upotrebom bizmut-subnitrata i tekućeg parafina. Za istraživanje su odabrane 64 četvrti vimena u kojima bakteriološkom kulturom nije bilo utvrđene infekcije 60 dana prije očekivanog teljenja. Četvrti su nasumično podijeljene u dvije skupine (skupina A i skupina B) sa po 32 četvrti u svakoj skupini. U skupini A, tijekom suhostaja, kravama su zatvoreni sisni kanali, dok u kontrolnoj skupini B nije proveden nikakav tretman. Uzorci mlijeka iz svih skupina podvrgnuti su testiranju bakteriološkom kulturom u vrijeme suhostaja i 1 – 3 dana poslije teljenja. Incidencija intramamarnih infekcija između suhostaja i teljenja bila je znakovito niža u skupini A u usporedbi sa skupinom B (12,5 % prema 34,4 %). Incidencija novih intramamarnih infekcija u skupinama A i B bila je znakovito niža za Streptococcus uberis (3,13 % prema 18,75 %) i Streptococcus dysgalactiae (3,13 % prema 12,5 %). Rezultati istraživanja pokazuju da zatvaranje sisnih kanala u suhostaju pomaže u smanjivanju incidencije novih intramamarnih infekcija

Bose-Einstein Condensates in Rotating Lattices

Strongly interacting bosons in 2D in a rotating square lattice are investigated via a modified Bose-Hubbard Hamiltonian. Such a system corresponds to a rotating lattice potential imprinted on a trapped Bose-Einstein condensate. Second-order quantum phase transitions between states of different symmetries are observed at discrete rotation rates. For the square lattice we study, there are four possible ground-state symmetries.Comment: 4 pages, 5 figures, Accepted for publication in PRL v2: Replaced phase winding labels with symmetry eigenstate indices, replaced Gaussian Ansatz with more general treatment and other minor change

A hospital based retrospective study on hepatotropic viruses as a cause of acute viral hepatitis in children in Uttarakhand, India

Introduction: Acute viral hepatitis in children is a serious health problem throughout the world. Aims and Objective: To determine the profile of Hepatitis A, B, C and E as a cause of acute viral hepatitis in children in a tertiary care hospital of Uttarakhand, India. Material and Methods: In this retrospective study, data was collected from the records of paediatric patients who underwent testing for one or more of the hepatitis viruses. Serum samples were tested for Anti-HAV IgM and Anti-HEV IgM by Enzyme Linked Immunosorbent Assay (ELISA) and Hepatitis B surface antigen and Anti HCV antibodies by enhanced chemiluminiscence.  Results: Among total of 252 patients suffering from Acute Viral Hepatitis (AVH), males predominated over females with 72.2 % vs. 27.8 %. Hepatitis A virus (72.6 %) was found to be the leading cause of AVH in our hospital followed by HBV (16.7 %), HEV (9.5 %) and the least common was HCV (1.1 %). Co-infection was seen in only 2 cases i.e one as HAV-HEV (0.4%) and other as HAV- HBV (0.4%). Out of all the cases of AVH, 9.5 % were suffering from Acute Hepatic Failure. Hepatitis A virus was found to be the most common cause of acute hepatic failure (50 %), followed by Hepatitis B (37.5 %) and Hepatitis E (12.5 %).  Conclusions: Hepatotropic viruses are quite prevalent in children in our country. Thus to control faeco-orally transmitted viruses i.e Hepatitis A and hepatitis E, awareness about healthy hygienic practices should be emphasized upon. Also hepatitis A vaccination can be recommended to be included in national immunization schedule. To prevent parenterally transmitted viruses like Hepatitis B and hepatitis C, use of sterile needles and syringes while tattooing, ear piercing and avoiding injections through unregistered medical practitioners should be done. Vaccination for hepatitis B should be routinely done

Quantized Vortex States of Strongly Interacting Bosons in a Rotating Optical Lattice

Bose gases in rotating optical lattices combine two important topics in quantum physics: superfluid rotation and strong correlations. In this paper, we examine square two-dimensional systems at zero temperature comprised of strongly repulsive bosons with filling factors of less than one atom per lattice site. The entry of vortices into the system is characterized by jumps of 2 pi in the phase winding of the condensate wavefunction. A lattice of size L X L can have at most L-1 quantized vortices in the lowest Bloch band. In contrast to homogeneous systems, angular momentum is not a good quantum number since the continuous rotational symmetry is broken by the lattice. Instead, a quasi-angular momentum captures the discrete rotational symmetry of the system. Energy level crossings indicative of quantum phase transitions are observed when the quasi-angular momentum of the ground-state changes.Comment: 12 Pages, 13 Figures, Version

Dissecting the Role of Critical Residues and Substrate Preference of a Fatty Acyl-CoA Synthetase (FadD13) of Mycobacterium tuberculosis

Newly emerging multi-drug resistant strains of Mycobacterium tuberculosis (M.tb) severely limit the treatment options for tuberculosis (TB); hence, new antitubercular drugs are urgently needed. The mymA operon is essential for the virulence and intracellular survival of M.tb and thus represents an attractive target for the development of new antitubercular drugs. This study is focused on the structure-function relationship of Fatty Acyl-CoA Synthetase (FadD13, Rv3089) belonging to the mymA operon. Eight site-directed mutants of FadD13 were designed, constructed and analyzed for the structural-functional integrity of the enzyme. The study revealed that mutation of Lys487 resulted in ∼95% loss of the activity thus demonstrating its crucial requirement for the enzymatic activity. Comparison of the kinetic parameters showed the residues Lys172 and Ala302 to be involved in the binding of ATP and Ser404 in the binding of CoenzymeA. The influence of mutations of the residues Val209 and Trp377 emphasized their importance in maintaining the structural integrity of FadD13. Besides, we show a synergistic influence of fatty acid and ATP binding on the conformation and rigidity of FadD13. FadD13 represents the first Fatty Acyl-CoA Synthetase to display biphasic kinetics for fatty acids. FadD13 exhibits a distinct preference for C26/C24 fatty acids, which in the light of earlier reported observations further substantiates the role of the mymA operon in remodeling the cell envelope of intracellular M.tb under acidic conditions. A three-dimensional model of FadD13 was generated; the docking of ATP to the active site verified its interaction with Lys172, Ala302 and Lys487 and corresponded well with the results of the mutational studies. Our study provides a significant understanding of the FadD13 protein including the identification of residues important for its activity as well as in the maintenance of structural integrity. We believe that the findings of this study will provide valuable inputs in the development of inhibitors against the mymA operon, an important target for the development of antitubercular drugs

Hall effects in Bose-Einstein condensates in a rotating optical lattice

Using the Kubo formalism, we demonstrate fractional quantum Hall features in a rotating Bose-Einstein condensate in a co-rotating two-dimensional optical lattice. The co-rotating lattice and trap potential allow for an effective magnetic field and compensation of the centrifugal potential. Fractional quantum Hall features are seen for the single-particle system and for few strongly interacting many-particle systems.Comment: 11 pages, 13 figure

mRNA Structural Constraints on EBNA1 Synthesis Impact on In Vivo Antigen Presentation and Early Priming of CD8(+) T Cells

Recent studies have shown that virally encoded mRNA sequences of genome maintenance proteins from herpesviruses contain clusters of unusual structural elements, G-quadruplexes, which modulate viral protein synthesis. Destabilization of these G-quadruplexes can override the inhibitory effect on self-synthesis of these proteins. Here we show that the purine-rich repetitive mRNA sequence of Epstein-Barr virus encoded nuclear antigen 1 (EBNA1) comprising G-quadruplex structures, limits both the presentation of MHC class I-restricted CD8(+) T cell epitopes by CD11c(+) dendritic cells in draining lymph nodes and early priming of antigen-specific CD8(+) T-cells. Destabilization of the G-quadruplex structures through codon-modification significantly enhanced in vivo antigen presentation and activation of virus-specific T cells. Ex vivo imaging of draining lymph nodes by confocal microscopy revealed enhanced antigen-specific T-cell trafficking and APC-CD8(+) T-cell interactions in mice primed with viral vectors encoding a codon-modified EBNA1 protein. More importantly, these antigen-specific T cells displayed enhanced expression of the T-box transcription factor and superior polyfunctionality consistent with the qualitative impact of translation efficiency. These results provide an important insight into how viruses exploit mRNA structure to down regulate synthesis of their viral maintenance proteins and delay priming of antigen-specific T cells, thereby establishing a successful latent infection in vivo. Furthermore, targeting EBNA1 mRNA rather than protein by small molecules or antisense oligonucleotides will enhance EBNA1 synthesis and the early priming of effector T cells, to establish a more rapid immune response and prevent persistent infection