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OPTIMISATION OF TOTAL RNA EXTRACTION FROM BOVINE OOCYTES AND EMBRYOS FOR GENE EXPRESSION STUDIES AND EFFECTS OF CRYOPROTECTANTS ON TOTAL RNA EXTRACTION. - Tï¸ Sï¸¡itologiiï¸ aï¸¡ i genetika
Gene expression is required for understanding bovine oocytes meiotic maturation as well as the potential of embryonic development. In the present study a standardized reagent protocol for total RNA extraction was designed for bovine oocytes and embryos, which is considered specific and less expensive. For such purpose oocytes (n = 795) recovered from about 80 ovaries were divided in three groups: Group 1 modified Trizol (MTP, n = 355); Group 2 Guanidinium thiocyanate protocol (GNTC, n = 140) and Group 3 Commercial Kit protocol (CKP, n = 60). Oocytes belonging to group 1 (n = 100) and 3 (n = 20) were subjected to vitrification using two cryoprotectants 1,2 propandiol (PROH) or Dimethylsulfoxide (DMSO). The 240 remaining oocytes were divided into 3 groups in which 100 were used, in fresh, for in vitro fertilization, and 140 oocytes were vitrified using PROH (n = 70) and DMSO (n = 70) as cryoprotectants, being then fertilized in vitro after thawing. Embryos were used nine days after fertilization. Gene amplification (SDHA, (GAPDH and DNMT1) was performed in oocytes, and gene quantification (DNMT1) in in vitro produced embryos at the stage of blastocyst (n = 10). Efficiency of the extraction was further compared. The purity of all samples to different protocols ranged from 1.10 to 1.25 for GNTC protocol; from 2.05 to 2.63 for the CKP and from 1.50 to 2.11 for the developed MTP, being the last one nearest to the expected purity levels for RNA samples (1.7 to 2.0). On average, for 30 fresh oocytes, from spectrophotometer readings, total RNA concentration was 127.8 Â± 9.3 ng Î¼l(-1) for MTP, against 46.4 Â± 9.5 ng Î¼l(-1) from CKP and 476 Â± 12.9 ng Î¼l(-1) for GNTC protocol. Using the MTP to evaluate RNA in 30 vitrified/thawed oocytes, resulted in a total RNA concentration of 61.3 Â± 3.3 ng Î¼l(-1) and 40.0 Î¼ 12.4 ng Î¼(-1), respectively for DMSO and PROH. Regarding total RNA concentration and purity, in blastocyst stage, more purity was observed in DMSO as compared to PROH (1.8 vs 1.2) (p < 0.05). Better results were also observed on the MTP for gene amplification when compared with the other protocols. For gene quantification, the proposed protocol quantified DNMT1 gene with PCR efficiency (0.933) after normalization against GAPDH and SDHA. Amplification and quantification of genes proved specificity and efficiency of the MTP over the other protocols.
Influence of CO2 and Temperature on Metabolism and Development of Helicoverpa armigera (Noctuidae: Lepidoptera). - Environmental entomology
Climate change will have a major bearing on survival and development of insects as a result of increase in CO2 and temperature. Therefore, we studied the direct effects of CO2 and temperature on larval development and metabolism in cotton bollworm, Helicoverpa armigera (HÃ¼bner). The larvae were reared under a range of CO2 (350, 550, and 750â€‰ppm) and temperature (15, 25, 35, and 45Â°C) regimes on artificial diet. Elevated CO2 negatively affected the larval survival, larval weight, larval period, pupation, and adult emergence, but showed a positive effect on pupal weight, pupal period, and fecundity. Increase in temperature exhibited a negative effect on larval survival, larval period, pupal weights, and pupal period, but a positive effect on larval growth. Pupation and adult emergence were optimum at 25Â°C. Elevated CO2 and temperature increased food consumption and metabolism of larvae by enhancing the activity of midgut proteases, carbohydrases (amylase and cellulase), and mitochondrial enzymes and therefore may cause more damage to crop production. Elevated CO2 and global warming will affect insect growth and development, which will change the interactions between the insect pests and their crop hosts. Therefore, there is need to gain an understanding of these interactions to develop strategies for mitigating the effects of climate change.Â© The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Photodynamic Efficiency: From Molecular Photochemistry to Cell Death. - International journal of molecular sciences
Photodynamic therapy (PDT) is a clinical modality used to treat cancer and infectious diseases. The main agent is the photosensitizer (PS), which is excited by light and converted to a triplet excited state. This latter species leads to the formation of singlet oxygen and radicals that oxidize biomolecules. The main motivation for this review is to suggest alternatives for achieving high-efficiency PDT protocols, by taking advantage of knowledge on the chemical and biological processes taking place during and after photosensitization. We defend that in order to obtain specific mechanisms of cell death and maximize PDT efficiency, PSes should oxidize specific molecular targets. We consider the role of subcellular localization, how PS photochemistry and photophysics can change according to its nanoenvironment, and how can all these trigger specific cell death mechanisms. We propose that in order to develop PSes that will cause a breakthrough enhancement in the efficiency of PDT, researchers should first consider tissue and intracellular localization, instead of trying to maximize singlet oxygen quantum yields in in vitro tests. In addition to this, we also indicate many open questions and challenges remaining in this field, hoping to encourage future research.
Synthesis and characterization of Î³-ferric oxide nanoparticles and their effect on Solanum lycopersicum. - Environmental science and pollution research international
Î³-Ferric oxide nanoparticles are synthesized through modern and facile ayurvedic route followed by normal and special purification steps, which are both cost-effective and eco-friendly. These synthesized Î³-ferric oxide nanoparticles were applied on Solanum lycopersicum to search the effect on chlorophyll content. This process involves multiple filtration and calcination steps. The synthesized samples were analyzed by X-ray diffraction (XRD), UV-visible (UV-vis) spectroscopy, transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), and particle size analysis (PSA) to identify the purification step's influence on the structural, optical, morphological, magnetic, and particle size properties of ferric oxide nanoparticles (Î³-phase). X-ray diffraction has revealed that ferric oxide nanoparticles have rhombohedral structure of Î±-phase (hematite) in initial purification process later transformed into cubic structure Î³-phase (maghemite). UV-vis spectroscopy analysis has clearly shown that by repetitive purification steps, Î»max has increased from 230 to 340Â nm. TEM result has an intercorrelation with XRD results. Î³-Ferric oxide nanoparticles were tested on Solanum lycopersicum (tomato seeds). The changes in the contents of chlorophyll a, chlorophyll b, and total carotene were studied using spectral measurements at two different dosages-0.5 and 2Â M. As a result, at 0.5-M concentration, magnetic nanoparticles exhibit fruitful results by increasing the crop yield and being more resistant to chlorosis.
Attentional Orienting to Social and Nonsocial Cues in Early Deaf Adults. - Journal of experimental psychology. Human perception and performance
In 2 experiments we investigated attentional orienting to nonpredictive social and nonsocial cues in deaf observers. In Experiment 1a, 22 early deaf adults and 23 hearing controls performed a peripheral shape-discrimination task, while uninformative central gaze cues validly and invalidly cued the location of the target. As an adaptation to the lack of audition, we expected deaf adults to show a larger impact of gaze cuing on attentional orienting compared with hearing controls. However, contrary to our predictions, deaf participants did not respond faster to cued compared with uncued targets (gaze-cuing effect; GCE), and this behavior partly correlated with early sign language acquisition. Experiment 1b showed a reliable GCE in 13 hearing native signers, thus excluding a key role of early sign language acquisition in explaining the lack of GCE in the response times of deaf participants. To test whether the resistance to uninformative central cues extends to nonsocial cues, in Experiment 2 nonpredictive arrow cues were presented to 14 deaf and 14 hearing participants. Both groups of participants showed a comparable arrow-cuing effect. Together, our findings suggest that deafness may selectively limit attentional-orienting triggered by central irrelevant gaze cues. Possible implications for plasticity related to deafness are discussed. (PsycINFO Database Record(c) 2015 APA, all rights reserved).
Metagenomic Assembly and Draft Genome Sequence of an Uncharacterized Prevotella sp. from Nelore Rumen. - Genome announcements
Prevotella is one of the most abundant genera in bovine rumen, although no genome has yet been assembled by a metagenomics approach applied to Brazilian Nelore. We report the draft genome sequence of Prevotella sp., comprising 2,971,040Â bp, obtained using the Illumina sequencing platform. This genome includes 127 contigs and presents a low 48% GC.Copyright Â© 2015 Kishi et al.
Directional dominance on stature and cognition inÂ diverse human populations. - Nature
Homozygosity has long been associated with rare, often devastating, Mendelian disorders, and Darwin was one of the first to recognize that inbreeding reduces evolutionary fitness. However, the effect of the more distant parental relatedness that is common in modern human populations is less well understood. Genomic data now allow us to investigate the effects of homozygosity on traits of public health importance by observing contiguous homozygous segments (runs of homozygosity), which are inferred to be homozygous along their complete length. Given the low levels of genome-wide homozygosity prevalent in most human populations, information is required on very large numbers of people to provide sufficient power. Here we use runs of homozygosity to study 16 health-related quantitative traits in 354,224 individuals from 102 cohorts, and find statistically significant associations between summed runsÂ of homozygosity and four complex traits: height, forced expiratory lung volume in one second, general cognitive ability and educational attainment (P < 1 Ã— 10(-300), 2.1 Ã— 10(-6), 2.5 Ã— 10(-10) and 1.8 Ã— 10(-10), respectively). In each case, increased homozygosity was associated with decreased trait value, equivalent to the offspring of first cousins being 1.2 cm shorter and having 10 months' less education. Similar effect sizes were found across four continental groups and populations with different degrees of genome-wide homozygosity, providing evidence that homozygosity, rather than confounding, directly contributes to phenotypic variance. Contrary to earlier reports in substantially smaller samples, no evidence was seen of an influence of genome-wide homozygosity on blood pressure and low density lipoprotein cholesterol, or ten other cardio-metabolic traits. Since directional dominance is predicted for traits under directional evolutionary selection, this study provides evidence that increased stature and cognitive function have been positively selected in human evolution, whereas many important risk factors for late-onset complex diseases may not have been.
The multisensory body revealed through its cast shadows. - Frontiers in psychology
One key issue when conceiving the body as a multisensory object is how the cognitive system integrates visible instances of the self and other bodies with one's own somatosensory processing, to achieve self-recognition and body ownership. Recent research has strongly suggested that shadows cast by our own body have a special status for cognitive processing, directing attention to the body in a fast and highly specific manner. The aim of the present article is to review the most recent scientific contributions addressing how body shadows affect both sensory/perceptual and attentional processes. The review examines three main points: (1) body shadows as a special window to investigate the construction of multisensory body perception; (2) experimental paradigms and related findings; (3) open questions and future trajectories. The reviewed literature suggests that shadows cast by one's own body promote binding between personal and extrapersonal space and elicit automatic orienting of attention toward the body-part casting the shadow. Future research should address whether the effects exerted by body shadows are similar to those observed when observers are exposed to other visual instances of their body. The results will further clarify the processes underlying the merging of vision and somatosensation when creating body representations.
Asymmetric processing of mutant factor X Arg386Cys reveals differences between intrinsic and extrinsic pathway activation. - Biochimica et biophysica acta
Alterations in coagulation factor X (FX) activation, mediated by the extrinsic VIIa/tissue factor (FVIIa/TF) or the intrinsic factor IXa/factor VIIIa (FIXa/FVIIIa) complexes, can result in hemorrhagic/prothrombotic tendencies. However, the molecular determinants involved in substrate recognition by these enzymes are poorly defined. Here, we investigated the role of arginine 386 (chymotrypsin numbering c202), a surface-exposed residue on the FX catalytic domain. The naturally occurring FX386Cys mutant and FX386Ala variant were characterized. Despite the unpaired cysteine, recombinant (r)FX386Cys was efficiently secreted (88.6Â±21.3% of rFXwt) and possessed normal clearance in mice. rFX386Cys was also normally activated by FVIIa/TF and displayed intact amidolytic activity. In contrast, rFX386Cys activation by the FIXa/FVIIIa complex was 4.5-fold reduced, which was driven by a decrease in the kcat (1.6âˆ—10(-4)s(-1) vs 5.8âˆ—10(-4)s(-1), rFXwt). The virtually unaltered Km (70.6nM vs 55.6nM, rFXwt) suggested no major alterations in the FX substrate exosite. Functional assays in plasma supplemented with rFX386Cys indicated a remarkable reduction in the thrombin generation rate and thus in coagulation efficiency. Consistently, the rFX386Ala variant displayed similar biochemical features suggesting that global changes at position 386 impact the intrinsic pathway activation. These data indicate that the FXArg386 is involved in FIXa/FVIIIa-mediated FX activation and help in elucidating the bleeding tendency associated with the FX386Cys in a rare FX deficiency case. Taking advantage of the unpaired cysteine, the rFX386Cys mutant may be efficiently targeted by thiol-specific ligands and represent a valuable tool to study FX structure-function relationships both in vitro and in vivo.Copyright Â© 2015. Published by Elsevier B.V.
Somatotopy and temporal dynamics of sensorimotor interactions: evidence from double afferent inhibition. - The European journal of neuroscience
Moving and interacting with the world requires that the sensory and motor systems share information, but while some information about tactile events is preserved during sensorimotor transfer the spatial specificity of this information is unknown. Afferent inhibition (AI) studies, in which corticospinal excitability (CSE) is inhibited when a single tactile stimulus is presented before a transcranial magnetic stimulation pulse over the motor cortex, offer contradictory results regarding the sensory-to-motor transfer of spatial information. Here, we combined the techniques of AI and tactile repetition suppression (the decreased neurophysiological response following double stimulation of the same vs. different fingers) to investigate whether topographic information is preserved in the sensory-to-motor transfer in humans. We developed a double AI paradigm to examine both spatial (same vs. different finger) and temporal (short vs. long delay) aspects of sensorimotor interactions. Two consecutive electrocutaneous stimuli (separated by either 30 or 125Â ms) were delivered to either the same or different fingers on the left hand (i.e. index finger stimulated twice or middle finger stimulated before index finger). Information about which fingers were stimulated was reflected in the size of the motor responses in a time-constrained manner: CSE was modulated differently by same and different finger stimulation only when the two stimuli were separated by the short delay (PÂ =Â 0.004). We demonstrate that the well-known response of the somatosensory cortices following repetitive stimulation is mirrored in the motor cortex and that CSE is modulated as a function of the temporal and spatial relationship between afferent stimuli.Â© 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.
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6501 Windcrest Dr Ste 100 Plano, TX 75024
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