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Life Tables of Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae): with a Mathematical Invalidation for Applying the Jackknife Technique to the Net Reproductive Rate
Get PDFLife table data for the melon fly, Bactrocera cucurbitae (Coquillett), reared on cucumber (Cucumis sativus L.) were collected under laboratory and simulated field conditions. Means and standard errors of life table parameters were estimated for two replicates using the jackknife technique. At 25ºC, the intrinsic rates of increase (_r_) found for the two replicates were 0.1354 and 0.1002 day-1, and the net reproductive rates (_R_~0~) were 206.3 and 66.0 offspring, respectively. When the cucumbers kept under simulated field conditions were covered with leaves, the _r_ and _R_~0~ for the two replicates were 0.0935 and 0.0909 day-1, 17.5 and 11.4 offspring, respectively. However, when similar cucumbers were left uncovered, the _r_ and _R_~0~ for the two replicates were 0.1043 and 0.0904 day-1, and 27.7 and 10.1 offspring, respectively. Our results revealed that considerable variability between replicates in both laboratory and field conditions is possible; this variability should be taken into consideration in data collection and application of life tables. Mathematical analysis has demonstrated that applying the jackknife technique results in unrealistic pseudo-_R_~0~ and overestimation of its variance. We suggest that the jackknife technique should not be used for the estimation of variability of _R_~0~
QSAR & DOCKING APPROACH - POTENTIAL WAY TO NEW DRUG DEVELOPMENT
No full textWith today's need for discovering and developing new drug molecules, it is necessary to accept ways to save time and wet lab essentials. To this end, the QSAR and molecular docking approach is used widely by us. This poster describes steps for developing a new or modified moiety of a drug molecule.

Optogenetic control of genetically-targeted pyramidal neuron activity in prefrontal cortex
Get PDFA salient feature of prefrontal cortex organization is the vast diversity of cell types that support the temporal integration of events required for sculpting future responses. A major obstacle in understanding the routing of information among prefrontal neuronal subtypes is the inability to manipulate the electrical activity of genetically defined cell types over behaviorally relevant timescales and activity patterns. To address these constraints, we present here a simple approach for selective activation of prefrontal excitatory neurons in both in vitro and in vivo preparations. Rat prelimbic pyramidal neurons were genetically targeted to express a light-­activated nonselective cation channel, channelrhodopsin-­2, or a light-­driven inward chloride pump, halorhodopsin, which enabled them to be rapidly and reversibly activated or inhibited by pulses of light. These light responsive tools provide a spatially and temporally precise means of studying how different cell types contribute to information processing in cortical circuits. Our customized optrodes and optical commutators for in vivo recording allow for efficient light delivery and recording and can be requested at www.neuro-­cloud.net/nature-precedings/baratta
On the origin of the mitochondrial genetic code: Towards a unified mathematical framework for the management of genetic information
Get PDFThe origin of the genetic code represents one of the most challenging problems in molecular evolution. The genetic code is an important universal feature of extant organisms and indicates a common ancestry of different forms of life on earth. Known variants of the genetic code can be mainly divided in mitochondrial and nuclear classes. Here we provide a new insight on the origin of the mitochondrial genetic code: we found that its degeneracy distribution can be explained by using a mathematical approach recently developed for the description of the Euplotes nuclear variant of the genetic code. The results point to a primeval mitochondrial genetic code composed of four base codons, which we call tesserae, that, among other features, exhibit outstanding error detection capabilities. The theoretical description suggests also a formulation of a plausible biological theory about the origin of protein coding. Such theory is based on the symmetry properties of hypothetical primeval chemical adaptors between nucleic acids and amino acids (ancient tRNA’s). Our paper provides a unified mathematical framework for different hypotheses on the origin of genetic coding. Also, it contributes to revisit our present view about the evolutionary steps that led to extant genetic codes by giving a new first-principles perspective on the difficult problem of the origin of the genetic code, and consequently, on the origin of life on earth
Ajuvant effect of a Synthetic Aluminium - Magnesium Silicate on chloroquine phosphate, against Plasmodium berghei.
Get PDFAbstract effect of a synthetic Aluminium - Magnesium Silicate (AMS) on antiplasmodial activity of chloroquine was tested. Plasmodium berghei-infected mice were treated with 7 mg/kg, 5 mg/kg and 3 mg/kg chloroquine, respectively. The two subgroups in each experiment were treated with chloroquine alone and with chloroquine in AMS respectively. Parasitaemia (%) of the group treated with 7 mg/kg was higher than that of the control. At 5 mg/kg, chloroquine treatment significantly reduced parasitaemia from 3.60 to 2.46 (P =0.01). Incorporating chloroquine in AMS significantly improved its ability to reduce P. berghei parasitaemia at 5 mgkg and at 3 mg/kg, from 2.46 0.21 to 1.57 0.25 (P = 0.01) and from 3.82 0.06 to 2.12 0.08 (P =0.01 ). It also increased mortality of mice treated at 7 mg/kg from 20 to 80 %
Unique for human centromeric regions of interphase chromatin homing (CENTRICH) govern dynamic features of chromatin fractal globules
No full textWe report the results of the genome-wide alignment of inter- and intra-chromosomal chromatin interactions within the context of interphase chromatin binding to nuclear lamina and nucleolus. For all human chromosomes, a significant correlation exists between binding of chromosomal loci to nuclear lamina and segregation into spatially-defined distinct compartments of genome-wide chromatin interactions identified by Hi-C method. We report identification of near-centromeric intergenic regions on human chromosomes (chr2; chr10; chr17; chr1), which are highly enriched for interphase chromatin homing sites and function as attractors of long-range physical interactions (Centromeric Regions of Interphase Chromatin Homing, CENTRICH). CENTRICH are engaged in 397-1526 pair-wise interactions per 1 Kb distance, which represents 199 - 716-fold enrichment of interphase chromatin homing sites compared to genome-wide average (2-tail Fisher's exact test p values range 2.10E-101 - 1.08E-292). CENTRICH represent unique for human highly homologous DNA sequences of 3.9 - 22.4 Kb in size which are: 1) associated with nucleolus; 2) exhibit remarkably diverse regulatory protein contexts of chromatin state maps; 3) bind multiple intergenic disease-associated genomic loci (IDAGL) with documented long-range enhancer activities and established links to increased risk of developing epithelial malignancies and other common human disorders. For cancer, coronary artery disease, and type 2 diabetes, there is a statistically significant inverse correlation between the genome-wide association studies (GWAS)-defined odds ratios of increased risk of a disease and distances of SNP loci homing sites to the middle-point genomic coordinates of CENTRICH. We conclude that interactions with nucleolus and nuclear lamina may have a physiologically and pathologically significant global impact on 3D genome architecture by governing a dynamic transition of large segments of interphase human chromosomes from the open loop to folded fractal globule conformations. We propose that emergence of CENTRICH in genome's architecture during the evolution contributes to distinct phenotypic features of H.sapiens
When Spandrels Become Arches: Neural crosstalk and the evolution of consciousness
Get PDFOnce cognition is recognized as having a 'dual' information source, the information theory chain rule implies that isolating coresident information sources from crosstalk requires more metabolic free energy than permitting correlation. This provides conditions for an evolutionary exaptation leading to the rapid, shifting global neural broadcasts of consciousness. The argument is quite analogous to the well-studied exaptation of noise to trigger stochastic resonance amplification in neurons and neuronal subsystems. Astrobiological implications are obvious
Neural Coding of Green Flash in Retinal Bipolar Pathways
Get PDFWhat visual information do the graded potentials among retinal bipolar pathways actually transmit from photoreceptors to ganglion cells? The answer does not exist. Even the graded electric signals have not been understood completely. Here, this paper tries to analyze the encoding mechanisms of graded signals among the parallel bipolar pathways in response to brief green flash. The typical ON, OFF and ON-OFF bipolar cells simultaneously abstracted vectors from green flash stimulus with sine-like functions on their dendritic plane. Atypical bipolar cell had the synchronously monopolar response in contrast to the bipolar responses of typical bipolar cells, they also annotated green flash with facilitated stochastic (asynchronous and rate-coded) responses. Some complex ON-OFF bipolar cells with large voltage-gated Na+ current could generate high-frequent asynchronous responses, others had synchronous ON-OFF responses to green flash. The green flash was synchronously and asynchronously represented by the multiple-dimension signaling space among the parallel bipolar pathways. These results unraveled the multiple-dimension neural codes for brief green flash, demonstrated the superior encoding capability of parallel bipolar pathways, and suggested the electrophysiological mechanisms of vision such as color space
Oxidative Stress and Mitochondrial Injury in Chronic Multisymptom Conditions: From Gulf War Illness to Autism Spectrum Disorder
Get PDFBackground: Overlapping chronic multisymptom illnesses (CMI) include Chronic Fatigue Syndrome (CFS), fibromyalgia, irritable bowel syndrome, multiple chemical sensitivity, and Gulf War illness (GWI), and subsets of autism spectrum disorder (ASD). GWI entails a more circumscribed set of experiences that may provide insights of relevance to overlapping conditions.
Objectives: To consolidate evidence regarding a role for oxidative stress and mitochondrial dysfunction (OSMD), as primary mediators in CMI, using GWI as a departure point.
Methods: Exposure relations, character, timecourse and multiplicity of symptoms, and objective correlates of GWI are compared to expectation for OSMD. Objective correlates of OSMD in GWI and overlapping conditions are examined. 
Discussion: OSMD is an expected consequence of known GWI exposures; is compatible with symptom characteristics observed; and accords with objective markers and health conditions linked to GWI, extending to autoimmune disease and infection. Emergent triangulating evidence directly supports OSMD in multisymptom “overlap” CMI conditions, with similarities to, and diagnosed at elevated rates in, GWI, suggesting a common role in each. 
Conclusions: GWI is compatible with a paradigm by which uncompensated exposure to oxidative/nitrative stressors accompanies and triggers mitochondrial dysfunction, cell energy compromise, and multiple downstream effects such as vulnerability to autoantibodies. This promotes a profile of protean symptoms with variable latency emphasizing but not confined to energy-demanding post-mitotic tissues, according with (and accounting for) known properties of multisystem overlap conditions. This advances understanding of GWI; health conditions attending GWI at elevated rates; and overlap conditions like CFS and ASD, providing prospects for vulnerability assessment, mitigation of progression, treatment, and future prevention – with implications germane to additive and excessive environmental oxidative stressor exposures in the civilian setting.

Using TreeBASE from R
Get PDFI introduce an R package allowing programmatic access to the phylogenetic data in the TreeBASE archive and highlight why this is important