Alteration in the in vitro activity of milk leukocytes during different parity in high yielding cross-bred cows

In vitro activity of milk leukocytes (viz. neutrophils, lymphocytes and macrophages) was evaluated in forty-eight (48) clinically healthy high-yielding cross-bred cows of mid-lactation stage (100–200 days of lactation), divided into four groups namely 1st parity (n = 12), 2nd parity (n = 12), 3rd parity (n = 12) and 4th and above parity (n = 12). Milk samples were taken (250 ml/cow) were taken. Milk somatic cell counts (SCC) and differential leukocyte counts (DLC) were performed microscopically. In vitro phagocytic index (PI) of milk neutrophils and macrophages was evaluated by colorimetric nitro blue tetrazolium reductive assay. Mitogen-induced milk lymphocyte blastogenic response was measured by colorimetric MTT (tetrazolium) assay after isolation of the milk leukocytes by density gradient centrifugation. Milk SCC differed significantly (p < 0.01) between different parity. Cows of 4 and above parity showed significantly (p < 0.01) higher milk SCC compared to primiparous cows. There was no significant difference in milk DLC during different parities in high-yielding cross-bred cows. There was a significant (p < 0.01) variation in lymphocyte blastogenesis amongst parity. The highest value of lymphocyte blastogenesis was seen at 3rd parity, whereas lowest value was obtained in the cows of both 1st and 4th or above parity. PI of milk neutrophils did not differ significantly between parity. PI of milk macrophages was significantly (p < 0.01) higher in 3rd parity and lower (p < 0.01) in 1st and 4th parities. The study indicated that depressed activity of milk lymphocytes and macropages was lower and SCC was higher in the cows of 4th and above parity indicating more mammary stress and hence susceptible to udder infection and mastitis. Therefore, better care and managemental interventions should be taken around these periods.     

Synthesis,Characterization and Evaluation of Cytotoxic Activities of Novel Aziridinyl Phosphonic Acid Derivatives

New aziridine 2‐phosphonic acids were prepared by monohydrolysis of the aziridine 2‐phosphonates that were obtained by the modified Gabriel?Cromwell reaction of vinyl phosphonate or α‐tosylvinyl phosphonate with a primary amine or a chiral amine. The cellular cytotoxicity of these compounds was tested against the HCT‐116 colorectal cancer cell lines and the CCD‐18Co normal colon fibroblast lines using the MTT assay. Three of the synthesized phosphonic acid derivatives 2e (ethyl hydrogen {(2S)‐1‐[(1S)‐1‐(naphthalen‐2‐yl)ethyl]aziridin‐2‐yl}phosphonate), 2h (ethyl hydrogen (1‐benzylaziridin‐2‐yl)phosphonate), and 2i (ethyl hydrogen (1‐cyclohexylaziridin‐2‐yl)phosphonate) showed higher cytotoxicity than the reference cancer treatment agent etoposide. Cell death was through a robust induction of apoptosis even more effectively than etoposide, a well‐known apoptosis inducing agent.     

The Structural Basis of the Farnesylated and Methylated KRas4B Interaction with Calmodulin

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Role of putrescine in ovary and embryo development in fruit bat Cynopterus sphinx during embryonic diapause

The aim of this study was to evaluate the effect of putrescine on ovarian activity and the rate of embryonic development in Cynopterus sphinx during delayed development. The result showed the presence of a rate‐limiting enzyme, ornithine decarboxylase‐1, in both ovary and utero‐embryonic unit of C. sphinx suggests a synthesis of putrescine in these sites. The corpus luteum showed increased, whereas utero‐embryonic unit showed decreased production of putrescine during delayed development as compared with the normal development. The bat treated in vivo with putrescine during delayed development showed increase in progesterone and estradiol synthesis, correlated with increased expression of luteinizing hormone receptor, steroidogenic acute receptor protein, and 3β‐hydroxysteroid dehydrogenase through extracellular signal‐regulated kinase (ERK1/2)‐mediated pathway in the ovary; but showed increase in the weight and expression of progesterone receptor (PR), B‐cell lymphoma 2, proliferating cell nucleus antigen, and vascular endothelial growth factor proteins in utero‐embryonic unit. The in vitro treatment of putrescine showed stimulatory whereas treatment with an inhibitor of putrescine, 2‐difluoromethylornithine caused an inhibitory effect on ovarian progesterone synthesis and cell proliferation, and cell survival in the utero‐embryonic unit. In conclusion, the putrescine showed two separate roles during embryonic diapause, high concentration of putrescine in the ovary may support corpus luteum and basal synthesis of progesterone, whereas a low level of putrescine causes retarded embryonic development by inhibiting cell proliferation in the utero‐embryonic unit. The bat treated with putrescine either directly promotes cell proliferation, cell survival, and angiogenic activities or acts indirectly increasing PR on utero‐embryonic unit thereby activating development in delayed embryo in C. sphinx.     

Probiotics L. acidophilus and B. clausii Modulate Gut Microbiota in Th1- and Th2-Biased Mice to Ameliorate Salmonella Typhimurium-Induced Diarrhea

Gut microbiota play important role in maintaining health. Probiotics are believed to augment it further. We aimed at comparing effects of probiotics, Lactobacillus acidophilus (LA) and Bacillus clausii (BC) (a) on the gut microbiota abundance and diversity and (b) their contributions to control intestinal dysbiosis and inflammation in Th1- and Th2-biased mice following Salmonella infection. We report how could gut microbiota and the differential immune bias (Th1 or Th2) of the host regulate host responses when challenged with Salmonella typhimurium in the presence and absence of either of the probiotics. LA was found to be effective in ameliorating the microbial dysbiosis and inflammation caused by Salmonella infection, in Th1 (C57BL/6) and Th2 (BALB/c)-biased mouse. BC was able to ameliorate Salmonella-induced dysbiosis and inflammation in Th2 but not in Th1-biased mouse. These results may support probiotics LA as a treatment option in the case of Salmonella infection.

     

Deciphering the global phylogeography of a coastal shrub (Scaevola taccada) reveals the influence of multiple forces on contemporary population structure

The phylogeography of coastal plant species is heavily influenced by past sealevel fluctuations, dispersal barriers, and life-history traits, such as long-distance dispersal ability of the propagules. Unlike the widely studied mangroves, phylogeographic patterns have remained mostly obscure for other coastal plant species. In this study, we sampled 42 populations of Scaevola taccada (Gaertn.) Roxb., a coastal shrub of the family Goodeniaceae, from 17 countries across its distribution range. We used five chloroplast DNA (cpDNA) and 14 nuclear microsatellite (simple sequence repeat [SSR]) markers to assess the influence of abiotic factors and population genetic processes on the phylogeographic pattern of the species. Geographical distribution of cpDNA haplotypes suggests that the species originated in Australia, followed by historical dispersal and expansion of its geographic range. Multiple abiotic factors, including the sealevel changes during the Pleistocene, the presence of landmasses like the Malay Peninsula, and contemporary oceanic circulation patterns, restricted gene flow between geographically distinct populations, thereby creating low haplotype diversity and a strong population structure. Population genetic processes acted on these isolated populations, leading to high nuclear genetic diversity and population differentiation, as revealed from analyzing the polymorphic SSR loci. Although genetic divergence was mostly concordant between cpDNA and SSR data, asymmetrical gene flow and ancestral polymorphism could explain the discordance in the detailed genetic structure. Overall, our findings indicate that abiotic factors and population genetic processes interactively influenced the evolutionary history and current phylogeographic pattern of S. taccada across its distribution range.     

Biophysical characterization of anticoagulant hemextin AB complex from the venom of snake Hemachatus haemachatus

Hemextin AB complex from the venom of Hemachatus haemachatus is the first known natural anticoagulant that specifically inhibits the enzymatic activity of blood coagulation factor VIIa in the absence of factor Xa. It is also the only known heterotetrameric complex of two three-finger toxins. Individually only hemextin A has mild anticoagulant activity, whereas hemextin B is inactive. However, hemextin B synergistically enhances the anticoagulant activity of hemextin A and their complex exhibits potent anticoagulant activity. In this study we characterized the nature of molecular interactions leading to the complex formation. Circular dichroism studies indicate the stabilization of β-sheet in the complex. Hemextin AB complex has an increased apparent molecular diameter in both gas and liquid phase techniques. The complex formation is enthalpically favorable and entropically unfavorable with a negative change in the heat capacity. Thus, the anticoagulant complex shows less structural flexibility than individual subunits. Both electrostatic and hydrophobic interactions are important for the complexation; the former driving the process and the latter helping in the stabilization of the tetramer. The tetramer dissociates into dimers and monomers with the increase in the ionic strength of the solution and also with increase in the glycerol concentration in the buffer. The two dimers formed under each of these conditions display distinct differences in their apparent molecular diameters and anticoagulant properties. Based on these results, we have proposed a model for this unique anticoagulant complex.