Effect of Maternal Exposure of Fluoride on Biometals and Oxidative Stress Parameters in Developing CNS of Rat

Excessive intake of essential elements agitates elemental homeostasis resulting in their heterogeneous distribution. Distraction of these elements in central nervous system (CNS) have been demonstrated in many neurological disorders, which are vital in generating free radicals, causing oxidative stress, and contributing to neuronal maladies. The developing CNS is highly vulnerable to environmental agents, including fluoride. Fluorosis is one such disorder ensued from excessive consumption of fluoride containing water and/or foods that poses a greater threat to the life. Present study offers perturbations caused by fluoride toxicity on the level of biometal and antioxidant homeostasis and their interactions. Pregnant Wistar rats were exposed to 100- and 200-ppm fluoride (F⁻) in drinking water and controls with tap water. The pups born to them were used for the study. On 21st postnatal day, the concentration of fluoride, biometals, and oxidative stress markers were determined in discrete regions of CNS. The levels of fluoride, copper, and iron increased whereas manganese and zinc were decreased considerably. Among antioxidant enzymes, catalase, superoxide dismutase, and glutathione peroxidase were decreased and lipid peroxidation was increased with regional alterations. The correlation coefficient values among oxidative stress markers and biometals were either positive or negative and showed less significance during correlation. The results confirm that the fluoride provoked oxidative stress and biometal deformations are synergistic that successively governs the neuronal damage and developing CNS no longer prevents exacerbations of fluoride.     

Germline recombination in a novel Cre transgenic line,Prl3b1‐Cre mouse

Spermatogenesis is a complex and highly regulated process by which spermatogonial stem cells differentiate into spermatozoa. To better understand the molecular mechanisms of the process, the Cre/loxP system has been widely utilized for conditional gene knockout in mice. In this study, we generated a transgenic mouse line that expresses Cre recombinase under the control of the 2.5 kbp of the Prolactin family 3, subfamily b, member 1 (Prl3b1) gene promoter (Prl3b1‐cre). Prl3b1 was initially reported to code for placental lactogen 2 (PL‐2) protein in placenta along with increased expression toward the end of pregnancy. PL‐2 was found to be expressed in germ cells in the testis, especially in spermatocytes. To analyze the specificity and efficiency of Cre recombinase activity in Prl3b1‐cre mice, the mice were mated with reporter R26GRR mice, which express GFP ubiquitously before and tdsRed exclusively after Cre recombination. The systemic examination of Prl3b1‐cre;R26GRR mice revealed that tdsRed‐positive cells were detected only in the testis and epididymis. Fluorescence imaging of Prl3b1‐cre;R26GRR testes suggested that Cre‐mediated recombination took place in the germ cells with approximately 74% efficiency determined by in vitro fertilization. In conclusion, our results suggest that the Prl3b1‐cre mice line provides a unique resource to understand testicular germ‐cell development. genesis 54:389–397, 2016. © 2016 Wiley Periodicals, Inc.     

Methyl parathion induced alterations in monoaminergic system of developing rat pups

Methyl parathion induced alterations in the level of monoamines, viz. norepinephrine, dopamine and serotonin were studied in discrete regions of developing central nervous system of rat pups. A significant decrease in the level of monoamines noticed in methyl parathion toxicosis may be related to the altered neuronal activity and inefficiency, leading to depression and impairment in various behavioural activities. In contrast to AChE inhibition, monoamine oxidase (MAO) activity showed an increasing trend and it could cause deamination of catecholamines and accumulation of its metabolites. This suggests that an increased AChE inhibition may indirectly stimulate MAO activity in developing rat pups exposed to methyl parathion.     

Clearance of Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV) and immunological changes in experimentally injected Macrobrachium rosenbergii

Macrobrachium rosenbergii was experimentally challenged with Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV) to study the clearance of these viruses and consequent changes in various immunological parameters. The healthy animals were injected MrNV and XSV intramuscularly and various organ samples such as gill tissue, head soft tissue, pleopods and intestine were collected at different time intervals of 3, 5, 10, 15, 25, 50, 75 and 100 d post-infection (p.i.) to study the viral clearance. Tissue tropism and clearing of MrNV and XSV were confirmed by RT-PCR, nested RT-PCR and bioassay. These 2 viruses failed to cause mortality or clinical signs of disease in injected adult prawns during the experimental period of 100 days. The result of RT-PCR analysis revealed that all the organs showed positive for both viruses by single step RT-PCR on 3, 5 and 10 d p.i., positive by nested RT-PCR on 15 and 20 d p.i. and all the organs became negative at 25 d p.i. onwards. The viral inoculum prepared from the tissue of MrNV and XSV-injected M. rosenbergii at 3, 5, 10, 15 and 20 d p.i. caused 100% mortality in post-larvae of M. rosenbergii at 9, 8, 7, 10 and 10 d p.i., respectively whereas the inoculum prepared at 25, 50 and 100 d p.i. failed to cause significant mortality in post-larvae of prawn. Immunological parameters such as proPO, superoxide anion, SOD, THC, clotting time and oxyhemocyanin were determined in MrNV and XSV-injected prawns and significant differences in some of the immunological parameters were found in the early days p.i. and became insignificant in the later days p.i.     

Biodegradation of methyl parathion and <Emphasis Type="Italic">p</Emphasis>-nitrophenol: evidence for the presence of a <Emphasis Type="Italic">p</Emphasis>-nitrophenol 2-hydroxylase in a Gram-negative <Emphasis Type="Italic">Serratia</Emphasis> sp. strain DS001

A soil bacterium capable of utilizing methyl parathion as sole carbon and energy source was isolated by selective enrichment on minimal medium containing methyl parathion. The strain was identified as belonging to the genus Serratia based on a phylogram constructed using the complete sequence of the 16S rRNA. Serratia sp. strain DS001 utilized methyl parathion, p-nitrophenol, 4-nitrocatechol, and 1,2,4-benzenetriol as sole carbon and energy sources but could not grow using hydroquinone as a source of carbon. p-Nitrophenol and dimethylthiophosphoric acid were found to be the major degradation products of methyl parathion. Growth on p-nitrophenol led to release of stoichiometric amounts of nitrite and to the formation of 4-nitrocatechol and benzenetriol. When these catabolic intermediates of p-nitrophenol were added to resting cells of Serratia sp. strain DS001 oxygen consumption was detected whereas no oxygen consumption was apparent when hydroquinone was added to the resting cells suggesting that it is not part of the p-nitrophenol degradation pathway. Key enzymes involved in degradation of methyl parathion and in conversion of p-nitrophenol to 4-nitrocatechol, namely parathion hydrolase and p-nitrophenol hydroxylase component “A” were detected in the proteomes of the methyl parathion and p-nitrophenol grown cultures, respectively. These studies report for the first time the existence of a p-nitrophenol hydroxylase component “A”, typically found in Gram-positive bacteria, in a Gram-negative strain of the genus Serratia. Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.     

Growth promotion effect of Pichia guilliermondii in chilli and biocontrol potential of Hanseniaspora uvarum against Colletotrichum capsici causing fruit rot

In the present investigation, we have attempted to identify the potential two epiphytic yeast strains for growth promotion and management of chilli fruit rot. Seed treatment with Pichia guilliermondii showed increased seedling vigour index (55%), fresh weight (96%) and dry weight (45%) over untreated control. Furthermore, P. guilliermondii showed higher root colonisation ability, indole-3-acetic acid (IAA) production and phosphate solubilisation ability. On the other hand, seedling dip with Hanseniaspora uvarum induced higher levels of defence-related compounds in chilli seedlings challenge-inoculated with Colletotrichum capsici under glasshouse conditions. Among the different media tested, higher biomass of P. guilliermondii and H. uvarum was obtained in pine juice broth and sugarcane juice broth, respectively. Glycerol buffer formulation showed viability (>70%) of P. guilliermondii up to 4 months and H. uvarum up to 9 months when stored at ambient conditions. Seedling dip and foliar sprays with H. uvarum showed 37– 40% reduction in chilli fruit rot incidence under field conditions. It also showed higher (cumulative) accumulation of defence-related compounds in chilli leaves and ripe fruits under field conditions. The results of current investigation indicated a clear difference among the two epiphytic yeast strains. P. guilliermondii was identified as growth promoter of chilli and H. uvarum as antagonist of chilli fruit rot pathogen, C. capsici.     

Using the TAP component of the antigen-processing machinery as a molecular adjuvant

We hypothesize that over-expression of transporters associated with antigen processing (TAP1 and TAP2), components of the major histocompatibility complex (MHC) class I antigen-processing pathway, enhances antigen-specific cytotoxic activity in response to viral infection. An expression system using recombinant vaccinia virus (VV) was used to over-express human TAP1 and TAP2 (VV-hTAP1,2) in normal mice. Mice coinfected with either vesicular stomatitis virus plus VV-hTAP1,2 or Sendai virus plus VV-hTAP1,2 increased cytotoxic lymphocyte (CTL) activity by at least 4-fold when compared to coinfections with a control vector, VV encoding the plasmid PJS-5. Coinfections with VV-hTAP1,2 increased virus-specific CTL precursors compared to control infections without VV-hTAP1,2. In an animal model of lethal viral challenge after vaccination, VV-hTAP1,2 provided protection against a lethal challenge of VV at doses 100-fold lower than control vector alone. Mechanistically, the total MHC class I antigen surface expression and the cross-presentation mechanism in spleen-derived dendritic cells was augmented by over-expression of TAP. Furthermore, VV-hTAP1,2 increases splenic TAP transport activity and endogenous antigen processing, thus rendering infected targets more susceptible to CTL recognition and subsequent killing. This is the first demonstration that over-expression of a component of the antigen-processing machinery increases endogenous antigen presentation and dendritic cell cross-presentation of exogenous antigens and may provide a novel and general approach for increasing immune responses against pathogens at low doses of vaccine inocula.     

Differential methods of inoculation of plant growth-promoting rhizobacteria induce synthesis of phenylalanine ammonia-lyase and phenolic compounds differentially in chickpca

Foliar spray and micro-injection of plant growth-promoting rhizobacterial species, viz. Pseudomonas fluorescens and P. aeruginosa on chickpea induced synthesis of phenylalanine ammonia-lyase (PAL) when tested against Sclerotinia sclerotiorum. Induction of PAL was also associated with increased synthesis of phenolic compounds such as tannic, gallic, caffeic, chlorogenic and cinnamic acids. Treatment with P. fluorescens was found to be more effective in inducing phenolic compounds as compared to P. aeruginosa. However, persistence of PAL activity was observed more with P. aeruginosa. Although both the inoculation methods were effective, foliar application was found to be superior to micro-injection in terms of rapid PAL activity leading to the synthesis of phenolic compounds.