Bio-efficacy of different oil carriers in ultra low volume sprayer for management of pod borer,Helicoverpa armigera (Hübner) in pigeonpea ecosystem

A study was conducted to evaluate the bioefficacy of different oil carriers (sunflower oil, seamum oil, neem oil, mineral oil), sugar solution and water formulation to be used in ultra low volume sprayer (ULV) along with rynaxypyr 18.5 SC (Coragen) for the management of pod borer at the Agricultural Research Station, Gulbarga, Karnataka, India during the kharif season of 2011–2012. The results revealed that the sesamum oil carrier fits well with rynaxypyr 18.5 SC and recorded the lowest mean pod borer larval population after last spray (1.0 per five plants) the lowest pod damage (23.20%), grain damage (18.30%) and higher grain yield (9.43?q/ha) with a high B:C ratio of 3.64 in the plot sprayed with the sesamum oil carrier. The findings suggested that the sesamum oil carrier in ULV sprayer is suitable and practicable in pigeonpea ecosystem for effective management of pod borer with no risk of phytotoxicity, spray drift and operational difficulties. The foregoing studies indicated that the performance of sesamum oil carriers was superior to other carriers in terms of suppression of larval population, reduction in pod damage and harnessing higher yield.     

Sodium valproate potentiates staurosporine‐induced apoptosis in neuroblastoma cells via Akt/survivin independently of HDAC inhibition

Sodium valproate (VPA) has been recently identified as a selective class I histone deacetylase (HDAC) inhibitor and explored for its potential as an anti‐cancer agent. The anti‐cancer properties of VPA are generally attributed to its HDAC inhibitory activity indicating a clear overlap of these two actions, but the underlying mechanisms of its anti‐tumor effects are not clearly elucidated. The present study aimed to delineate the molecular mechanism of VPA in potentiating cytotoxic effects of anti‐cancer drugs with focus on inhibition of HDAC activity. Using human neuroblastoma cell lines, SK‐N‐MC, SH‐SY5Y, and SK‐N‐SH, we show that non‐toxic dose (2 mM) of VPA enhanced staurosporine (STS)‐induced cell death as assessed by MTT assay, PARP cleavage, hypodiploidy, and caspase 3 activity. Mechanistically, the effect of VPA was mediated by down regulation of survivin, an anti‐apoptotic protein crucial in resistance to STS‐mediated cytotoxicity, through Akt pathway. Knock down of class I HDAC isoforms remarkably inhibited HDAC activity comparable with that of VPA but had no effect on STS‐induced apoptosis. Moreover, MS‐275, a structurally distinct class I HDAC inhibitor did not affect STS‐mediated apoptosis, nor decrease the levels of survivin and Akt. Valpromide (VPM), an amide analog of VPA that does not inhibit HDAC also potentiated cell death in NB cells associated with decreased survivin and Akt levels suggesting that HDAC inhibition might not be crucial for STS‐induced apoptosis. The study provides new information on the possible molecular mechanism of VPA in apoptosis that can be explored in combination therapy in cancer. J. Cell. Biochem. 114: 854–863, 2013. © 2012 Wiley Periodicals, Inc.     

Tank treading of optically trapped red blood cells in shear flow

Tank-treading (TT) motion is established in optically trapped, live red blood cells (RBCs) held in shear flow and is systematically investigated under varying shear rates, temperature (affecting membrane viscosity), osmolarity (resulting in changes in RBC shape and cytoplasmic viscosity), and viscosity of the suspending medium. TT frequency is measured as a function of membrane and cytoplasmic viscosity, the former being four times more effective in altering TT frequency. TT frequency increases as membrane viscosity decreases, by as much as 10% over temperature changes of only 4°C at a shear rate of ∼43 s⁻¹. A threshold shear rate (1.5 ± 0.3 s⁻¹) is observed below which the TT frequency drops to zero. TT motion is also observed in shape-engineered (spherical) RBCs and those with cholesterol-depleted membranes. The TT threshold is less evident in both cases but the TT frequency increases in the latter cells. Our findings indicate that TT motion is pervasive even in folded and deformed erythrocytes, conditions that occur when such erythrocytes flow through narrow capillaries.     

Gut microbiome,diet, and conservation of endangered langurs in Sri Lanka

Understanding the mechanisms by which organisms respond to environmental change is critical to conservation biology. Recent research indicates that the gut microbiome may mediate mammalian responses to the environment and can be used as a biomarker to understand host ecological strategies. Here, we explore the relationship between the gut microbiome, host dietary niche, and potential resilience to habitat alteration using two closely related, sympatric non-human primate species: the tufted gray langur (Semnopithecus priam) and the purple-faced langur (Semnopithecus vetulus). The gray langur is suspected to be a habitat generalist less perturbed by anthropogenic disturbance, while the purple-faced langur is suspected to be a specialist more sensitive to disturbance. To test these characterizations, we assessed the gut microbiome using 16S rRNA gene amplicon sequencing of fecal samples collected from Kaludiyapokuna Forest Reserve, Sri Lanka (gray langur n = 50 samples, purple-faced langur n = 7 samples). Our results demonstrate that despite strong gut microbial similarities, gray langurs had a more diverse gut microbiome that harbored Prevotella and Akkermansia, taxa involved in starch degradation, while the purple-faced langur gut microbiome harbored Roseburia, Clostridium, and Ruminococcus, taxa involved in processing plant structural carbohydrates. Compared to related species in other locations, both Sri Lankan langurs harbored more pathogenic bacteria. These differences suggest that gray langurs have more generalist diets, making them more resilient to anthropogenic change, but also indicate that they are not impervious to human encroachment. Our findings suggest that microbiome analyses are an important tool for langur ecology and conservation, and should be integrated into ongoing studies.     

Effects of NR1H3 Genetic Variation on the Expression of Liver X Receptor α and the Progression of Alzheimer's Disease

Alzheimer''s disease (AD) has been postulated to involve defects in the clearance of amyloid-β (Aβ). Activation of liver X receptor α (LXRα) increases the expression of apolipoprotein E (ApoE) as well as cholesterol transporters ABCA1 and ABCG1, leading to augmented clearance of Aβ. We have previously shown that the C allele of rs7120118 in the NR1H3 gene encoding LXRα reduces the risk of AD. Here, we wanted to assess whether the rs7120118 variation affects the progression of AD and modulates the expression of NR1H3 and its downstream targets APOE, ABCA1 and ABCG1.We utilized tissue samples from the inferior temporal cortex of 87 subjects, which were subdivided according to Braak staging into mild, moderate and severe AD groups on the basis of AD-related neurofibrillary pathology. APOE ε4 allele increased soluble Aβ42 levels in the tissue samples in a dose-dependent manner, but did not affect the expression status of APOE. In contrast, the CC genotype of rs7120118 was underrepresented in the severe group, although this result did not reach statistical significance. Also, patients with the CC genotype of rs7120118 showed significantly decreased soluble Aβ42 levels as compared to the patients with TT genotype. Although the severity of AD did not affect NR1H3 expression, the mRNA levels of NR1H3 among the patients with CT genotype of rs7120118 were significantly increased as compared to the patients with TT genotype. These results suggest that genetic variation in NR1H3 modulates the expression of LXRα and the levels of soluble Aβ42.     

CD24 Expression Identifies Teratogen-Sensitive Fetal Neural Stem Cell Subpopulations: Evidence from Developmental Ethanol Exposure and Orthotopic Cell Transfer Models

Background

Ethanol is a potent teratogen. Its adverse neural effects are partly mediated by disrupting fetal neurogenesis. The teratogenic process is poorly understood, and vulnerable neurogenic stages have not been identified. Identifying these is a prerequisite for therapeutic interventions to mitigate effects of teratogen exposures.

Methods

We used flow cytometry and qRT-PCR to screen fetal mouse-derived neurosphere cultures for ethanol-sensitive neural stem cell (NSC) subpopulations, to study NSC renewal and differentiation. The identity of vulnerable NSC populations was validated in vivo, using a maternal ethanol exposure model. Finally, the effect of ethanol exposure on the ability of vulnerable NSC subpopulations to integrate into the fetal neurogenic environment was assessed following ultrasound guided, adoptive transfer.

Results

Ethanol decreased NSC mRNAs for c-kit, Musashi-1and GFAP. The CD24⁺ NSC population, specifically the CD24⁺CD15⁺ double-positive subpopulation, was selectively decreased by ethanol. Maternal ethanol exposure also resulted in decreased fetal forebrain CD24 expression. Ethanol pre-exposed CD24⁺ cells exhibited increased proliferation, and deficits in cell-autonomous and cue-directed neuronal differentiation, and following orthotopic transplantation into naïve fetuses, were unable to integrate into neurogenic niches. CD24^depleted cells retained neurosphere regeneration capacity, but following ethanol exposure, generated increased numbers of CD24⁺ cells relative to controls.

Conclusions

Neuronal lineage committed CD24⁺ cells exhibit specific vulnerability, and ethanol exposure persistently impairs this population’s cell-autonomous differentiation capacity. CD24⁺ cells may additionally serve as quorum sensors within neurogenic niches; their loss, leading to compensatory NSC activation, perhaps depleting renewal capacity. These data collectively advance a mechanistic hypothesis for teratogenesis leading to microencephaly.     

Synechococcus elongatus PCC 7942 is more tolerant to chromate as compared to Synechocystis sp. PCC 6803

Two unicellular cyanobacteria Synechocystis sp. PCC 6803 and Synechococcus elongatus PCC 7942 showed contrasting responses to chromate stress with EC₅₀ of 12 ± 2 and 150 ± 15 μM potassium dichromate respectively. There was no depletion of chromate in growth medium in both the cases. Using labeled chromate, very low accumulation (<1 nmol/10⁸ cells) was observed in Synechocystis after incubation for 24 h in light. No accumulation of chromate could be observed in Synechococcus under these conditions. Chromate oxyanion is known to enter the cells using sulfate uptake channels. Therefore, inhibition of sulfate uptake caused by chromate was monitored using ³⁵S labeled sulfate. IC₅₀ values of chromate for ³⁵sulfate uptake were higher in Synechococcus as compared to Synechocystis. The results suggested that the sulfate transporters in Synechococcus have lower affinity to chromate than those from Synechocystis possibly due to differences in affinity of sulfate receptors for chromate. Bioinformatic analyses revealed presence of sulfate and chromate transporters with considerable similarity; however, minor differences in these may play a role in their differential response to chromate. In both cases the IC₅₀ values decreased when sulfate concentration was reduced in the medium indicating competitive inhibition of sulfate uptake by chromate. Interestingly, Synechococcus showed stimulation of growth at concentrations of chromate less than 100 μM, which affected its cell size without disturbing the ultrastructure and thylakoid organization. In Synechocystis, growth with 12 μM potassium dichromate damaged the ultrastructure and thylakoid organization with slight elongation of the cells. The results suggested that Synechococcus possesses efficient strategies to prevent entry and to remove chromate from the cell as compared to Synechocystis. This is the first time a differential response of Synechococcus 7942 and Synechocystis 6803 to chromate is reported. The contrasting characteristics observed in the two cyanobacteria will be useful in understanding the basis of resistance or susceptibility to chromate.     

Prolonged Outbreak of Candida krusei Candidemia in Paediatric Ward of Tertiary Care Hospital

Mycopathologia - A sudden rise of Candida krusei candidemia cases was noticed in our hospital within 1&nbsp;year with maximum cases from paediatric unit. The present study reports the results...     

Mapping of fertility traits in Finnish Ayrshire by genome-wide association analysis

A whole-genome scan using single marker association was used to detect chromosome regions associated with seven female fertility traits in Finnish Ayrshire dairy cattle. The phenotypic data consisted of de-regressed estimated breeding values for 340 bulls which were estimated using a single trait model. Genotypes were obtained with the Illumina BovineSNP50 panel and a total of 35 630 informative, high-quality single nucleotide polymorphism (SNP) markers were used. The association analysis was performed using a mixed-model approach which fitted a fixed effect for each SNP and a random polygenic effect. We detected eleven genome-wide significant associations on eight different chromosomes. With at least chromosome-wise significance after Bonferroni correction, sixteen SNPs on nine chromosomes showed significant associations with one or more fertility traits. The results confirmed quantitative trait loci on three chromosomes (1, 2 and 20) for fertility traits previously reported for the same breed and one on chromosome four previously detected in Holstein cattle.     

Histone octamer trans-transfer: a signature mechanism of ATP-dependent chromatin remodelling unravelled in wheat nuclear extract

Background and Scope

In eukaryotes, chromatin remodelling complexes are shown to be responsible for nucleosome mobility, leading to increased accessibility of DNA for DNA binding proteins. Although the existence of such complexes in plants has been surmised mainly at the genetic level from bioinformatics studies and analysis of mutants, the biochemical existence of such complexes has remained unexplored.

Methods

Histone H1-depleted donor chromatin was prepared by micrococcal nuclease digestion of wheat nuclei and fractionation by exclusion chromatography. Nuclear extract was partially purified by cellulose phosphate ion exchange chromatography. Histone octamer trans-transfer activity was analysed using the synthetic nucleosome positioning sequence in the absence and presence of ATP and its analogues. ATPase activity was measured as ³²Pi released using liquid scintillation counting.

Key Results

ATP-dependent histone octamer trans-transfer activity, partially purified from wheat nuclei using cellulose phosphate, showed ATP-dependent octamer displacement in trans from the H1-depleted native donor chromatin of wheat to the labelled synthetic nucleosome positioning sequence. It also showed nucleosome-dependent ATPase activity. Substitution of ATP by ATP analogues, namely ATPγS, AMP-PNP and ADP abolished the octamer trans-transfer, indicating the requirement of ATP hydrolysis for this activity.

Conclusions

ATP-dependent histone octamer transfer in trans is a recognized activity of chromatin remodelling complexes required for chromatin structure dynamics in non-plant species. Our results suggested that wheat nuclei also possess a typical chromatin remodelling activity, similar to that in other eukaryotes. This is the first report on chromatin remodelling activity in vitro from plants.