Natural Rabies Infection in a Domestic Fowl (Gallus domesticus): A Report from India

Background

Rabies is a fatal encephalitis caused by viruses belonging to the genus Lyssavirus of the family Rhabdoviridae. It is a viral disease primarily affecting mammals, though all warm blooded animals are susceptible. Experimental rabies virus infection in birds has been reported, but naturally occurring infection of birds has been documented very rarely.

Principal Findings

The carcass of a domestic fowl (Gallus domesticus), which had been bitten by a stray dog one month back, was brought to the rabies diagnostic laboratory. A necropsy was performed and the brain tissue obtained was subjected to laboratory tests for rabies. The brain tissue was positive for rabies viral antigens by fluorescent antibody test (FAT) confirming a diagnosis of rabies. Phylogenetic analysis based on nucleoprotein gene sequencing revealed that the rabies virus strain from the domestic fowl belonged to a distinct and relatively rare Indian subcontinent lineage.

Significance

This case of naturally acquired rabies infection in a bird species, Gallus domesticus, being reported for the first time in India, was identified from an area which has a significant stray dog population and is highly endemic for canine rabies. It indicates that spill over of infection even to an unusual host is possible in highly endemic areas. Lack of any clinical signs, and fewer opportunities for diagnostic laboratory testing of suspected rabies in birds, may be the reason for disease in these species being undiagnosed and probably under-reported. Butchering and handling of rabies virus- infected poultry may pose a potential exposure risk.     

The Cdk5 Kinase Downregulates ATP-Gated Ionotropic P2X<Subscript>3</Subscript> Receptor Function Via Serine Phosphorylation

Cdk5 is an endogenous kinase activated by the neuronal-specific protein p35 and implicated in multiple neuronal functions, including modulation of certain pain responses. We investigated whether Cdk5 could regulate ATP-gated P2X₃ receptors that are members of the family of membrane proteins expressed by sensory neurons to transduce nociception in baseline and chronic pain. To study the potential P2X₃ receptor modulation by Cdk5, we co-transfected rat P2X₃ receptors and Cdk5 into HEK cells and observed increased P2X₃ receptor serine phosphorylation together with downregulation of receptor currents only when these genes were transfected together with the gene of the Cdk5 activator p35. The changes in receptor responses were limited to depressed current amplitude as desensitization and recovery were not altered. Transfection of p35 with P2X₃ similarly downregulated receptor responses, suggesting that this phenomenon could be observed even with constitutive Cdk5. The present data indicate a novel target to express the action of Cdk5 on membrane proteins involved in pain perception.     

Removal of Arsenic(III) from Waste Water Using Lactobacillus acidophilus

Lactobacillus acidophilus was used for the removal of As(III) from 50–2000 ppb As(III)-containing water solution. Biosorption of As(III) by L. acidophilus was dependent on concentration (50 to 2000 ppb) and time (0 to 3 h).L. acidophilus(1 mg dry wt/ml) was able to remove 30, 60, 300, 420, 600 ppb As(III) from 50, 100, 500, 1000, and 2000 ppb of As(III)-containing water solution, respectively, within 3 h at pH 7. Moreover, by increasing the biomass of L. acidophilus(2 mg dry wt/ml) removal of As(III) was enhanced 1.66, 1.33, 1.16, 1.42, and 1.33 times, respectively. Fourier transform infrared (FTIR) and electron spectroscopy for chemical analysis (ESCA) spectrum of As(III)-loaded biomass was also investigated. An FTIR sample spectrum of L. acidophilus fresh biomass and As(III)-loaded biomass showed band stretching of fresh and As(III)-loaded biomass for O-H, 3423.43 to 3385.04 cm^?1, and for C-O, 1742.82 to 1731.14 cm^?1, and signified that –OH and –CO groups were also involved in the removal of As(III) from As(III)-containing water solution.     

BRIT1/MCPH1 Is Essential for Mitotic and Meiotic Recombination DNA Repair and Maintaining Genomic Stability in Mice

BRIT1 protein (also known as MCPH1) contains 3 BRCT domains which are conserved in BRCA1, BRCA2, and other important molecules involved in DNA damage signaling, DNA repair, and tumor suppression. BRIT1 mutations or aberrant expression are found in primary microcephaly patients as well as in cancer patients. Recent in vitro studies suggest that BRIT1/MCPH1 functions as a novel key regulator in the DNA damage response pathways. To investigate its physiological role and dissect the underlying mechanisms, we generated BRIT1 ^−/− mice and identified its essential roles in mitotic and meiotic recombination DNA repair and in maintaining genomic stability. Both BRIT1 ^−/− mice and mouse embryonic fibroblasts (MEFs) were hypersensitive to γ-irradiation. BRIT1 ^−/− MEFs and T lymphocytes exhibited severe chromatid breaks and reduced RAD51 foci formation after irradiation. Notably, BRIT1 ^−/− mice were infertile and meiotic homologous recombination was impaired. BRIT1-deficient spermatocytes exhibited a failure of chromosomal synapsis, and meiosis was arrested at late zygotene of prophase I accompanied by apoptosis. In mutant spermatocytes, DNA double-strand breaks (DSBs) were formed, but localization of RAD51 or BRCA2 to meiotic chromosomes was severely impaired. In addition, we found that BRIT1 could bind to RAD51/BRCA2 complexes and that, in the absence of BRIT1, recruitment of RAD51 and BRCA2 to chromatin was reduced while their protein levels were not altered, indicating that BRIT1 is involved in mediating recruitment of RAD51/BRCA2 to the damage site. Collectively, our BRIT1-null mouse model demonstrates that BRIT1 is essential for maintaining genomic stability in vivo to protect the hosts from both programmed and irradiation-induced DNA damages, and its depletion causes a failure in both mitotic and meiotic recombination DNA repair via impairing RAD51/BRCA2''s function and as a result leads to infertility and genomic instability in mice.     

Surface modified zeolite, a novel carrier material for Azotobacter chroococcum

A new immobilization matrix based on zeolite has been developed to immobilize Azotobacter chroococcum, for fixing nitrogen, with an intention to hold the cells in the root zone of the plants and to protect them under stressful conditions. The matrix has been developed by modifying the surface of the zeolite with surfactant. This enhances the hydrophobicity of the material and also modifies the surface charge, which in turn enhances the immobilization. Surface modified zeolite-A (SMZ-A) has been compared with commercial zeolite-A (CZA) for immobilization efficiency. CZA is non-toxic for A. chroococcum but is inefficient to adsorb the cells whereas SMZ-A showed 100% adsorption of the microbial cells wherein it was observed that for 1 l of broth culture with total viable count of 10⁸ cfu ml⁻¹ cells of A. chroococcum, a minimum dose of 0.7 g SMZ-A and minimum contact time of 10 h is required to achieve 100% adsorption. Adsorption was confirmed by the cell count and light as well as scanning electron microscopy. Most importantly, the cells adsorbed on SMZ-A could fix the atmospheric nitrogen up to 13 mg g⁻¹ sucrose consumed, which was comparable with the control (unadsorbed cells), which confirms the survival and nitrogen fixation activity of the bacteria. Responsible Editor: Euan K. James.     

Maize Brittle stalk2 encodes a COBRA-like protein expressed in early organ development but required for tissue flexibility at maturity

The maize (Zea mays) brittle stalk2 (bk2) is a recessive mutant, the aerial parts of which are easily broken. The bk2 phenotype is developmentally regulated and appears 4 weeks after planting, at about the fifth-leaf stage. Before this time, mutants are indistinguishable from wild-type siblings. Afterward, all organs of the bk2 mutants turn brittle, even the preexisting ones, and they remain brittle throughout the life of the plant. Leaf tension assays and bend tests of the internodes show that the brittle phenotype does not result from loss of tensile strength but from loss in flexibility that causes the tissues to snap instead of bend. The Bk2 gene was cloned by a combination of transposon tagging and a candidate gene approach and found to encode a COBRA-like protein similar to rice (Oryza sativa) BC1 and Arabidopsis (Arabidopsis thaliana) COBRA-LIKE4. The outer periphery of the stalk has fewer vascular bundles, and the sclerids underlying the epidermis possess thinner secondary walls. Relative cellulose content is not strictly correlated with the brittle phenotype. Cellulose content in mature zones of bk2 mature stems is lowered by 40% but is about the same as wild type in developing stems. Although relative cellulose content is lowered in leaves after the onset of the brittle phenotype, total wall mass as a proportion of dry mass is either unchanged or slightly increased, indicating a compensatory increase in noncellulosic carbohydrate mass. Fourier transform infrared spectra indicated an increase in phenolic ester content in the walls of bk2 leaves and stems. Total content of lignin is unaffected in bk2 juvenile leaves before or after appearance of the brittle phenotype, but bk2 mature and developing stems are markedly enriched in lignin compared to wild-type stems. Despite increased lignin in bk2 stems, loss of staining with phloroglucinol and ultraviolet autofluorescence is observed in vascular bundles and sclerid layers. Consistent with the infrared analyses, levels of saponifiable hydroxycinnamates are elevated in bk2 leaves and stems. As Bk2 is highly expressed during early development, well before the onset of the brittle phenotype, we propose that Bk2 functions in a patterning of lignin-cellulosic interactions that maintain organ flexibility rather than having a direct role in cellulose biosynthesis.     

Scavenging effect of Indian grape polyphenols on 2,2'-diphenyl-1-picrylhydrazyl(DPPH) radical by electron spin resonance spectrometry

Antioxidant potency of Indian grape cultivars varying in their skin color, seed and polyphenol content (Bangalore blue, Pandhari sahebi, Sharad seedless and Thompson seedless) and their components (whole grapes, pulp with skin and seeds) was examined as 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity using electron spin resonance spectrometry. The total polyphenols in Indian grapes ranged between 3-51%. Extracted polyphenols caused a concentration dependent and significant loss in DPPH radical signal, similar to known antioxidants-Vitamin C, catechin and procyanidin B3 used as references. Among seedless cultivars, polyphenols from Sharad was more potent as antioxidant than Thompson, showing IC50 values of 1250 +/- 30 and 2650 +/- 125 microg/ml, respectively. The inhibitory effect of polyphenols from seedless grape cultivars was as effective as that of seeded variety. The results indicate that polyphenols extracted from Indian grapes/ components (with /without seeds) exhibited free radical scavenging activity and their chemopreventive properties need to be exploited by in vivo model system.     

Receptor interacting protein 140 regulates expression of uncoupling protein 1 in adipocytes through specific peroxisome proliferator activated receptor isoforms and estrogen-related receptor alpha

Expression of uncoupling protein 1 (Ucp1) mRNA is elevated in differentiated adipocytes derived from brown or white adipose tissue devoid of the nuclear receptor corepressor receptor interacting protein 140 (RIP140). Increased expression is mediated in part by the recruitment of peroxisome proliferator activated receptors alpha and gamma, together with estrogen-related receptor alpha, which functions through a novel binding site on the Ucp1 enhancer. This demonstrates that regulation of Ucp1 expression in the absence of RIP140 involves derepression of at least three different nuclear receptors. The ability to increase expression of Ucp1 by beta-adrenergic signaling is independent of RIP140, as shown by the action of the beta(3)-adrenergic agonist CL 316,243 to stimulate expression in both brown and white adipocytes in the presence and absence of the corepressor. Therefore, the expression of this metabolic uncoupling protein in adipose cells is regulated by inhibition as well as activation of distinct signaling pathways.