Whole-genome sequencing of the efficient industrial fuel-ethanol fermentative Saccharomyces cerevisiae strain CAT-1

The Saccharomyces cerevisiae strains widely used for industrial fuel-ethanol production have been developed by selection, but their underlying beneficial genetic polymorphisms remain unknown. Here, we report the draft whole-genome sequence of the S. cerevisiae strain CAT-1, which is a dominant fuel-ethanol fermentative strain from the sugarcane industry in Brazil. Our results indicate that strain CAT-1 is a highly heterozygous diploid yeast strain, and the ~12-Mb genome of CAT-1, when compared with the reference S228c genome, contains ~36,000 homozygous and ~30,000 heterozygous single nucleotide polymorphisms, exhibiting an uneven distribution among chromosomes due to large genomic regions of loss of heterozygosity (LOH). In total, 58 % of the 6,652 predicted protein-coding genes of the CAT-1 genome constitute different alleles when compared with the genes present in the reference S288c genome. The CAT-1 genome contains a reduced number of transposable elements, as well as several gene deletions and duplications, especially at telomeric regions, some correlated with several of the physiological characteristics of this industrial fuel-ethanol strain. Phylogenetic analyses revealed that some genes were likely associated with traits important for bioethanol production. Identifying and characterizing the allelic variations controlling traits relevant to industrial fermentation should provide the basis for a forward genetics approach for developing better fermenting yeast strains.     

Subcellular location of PKA controls striatal plasticity: stochastic simulations in spiny dendrites

Dopamine release in the striatum has been implicated in various forms of reward dependent learning. Dopamine leads to production of cAMP and activation of protein kinase A (PKA), which are involved in striatal synaptic plasticity and learning. PKA and its protein targets are not diffusely located throughout the neuron, but are confined to various subcellular compartments by anchoring molecules such as A-Kinase Anchoring Proteins (AKAPs). Experiments have shown that blocking the interaction of PKA with AKAPs disrupts its subcellular location and prevents LTP in the hippocampus and striatum; however, these experiments have not revealed whether the critical function of anchoring is to locate PKA near the cAMP that activates it or near its targets, such as AMPA receptors located in the post-synaptic density. We have developed a large scale stochastic reaction-diffusion model of signaling pathways in a medium spiny projection neuron dendrite with spines, based on published biochemical measurements, to investigate this question and to evaluate whether dopamine signaling exhibits spatial specificity post-synaptically. The model was stimulated with dopamine pulses mimicking those recorded in response to reward. Simulations show that PKA colocalization with adenylate cyclase, either in the spine head or in the dendrite, leads to greater phosphorylation of DARPP-32 Thr34 and AMPA receptor GluA1 Ser845 than when PKA is anchored away from adenylate cyclase. Simulations further demonstrate that though cAMP exhibits a strong spatial gradient, diffusible DARPP-32 facilitates the spread of PKA activity, suggesting that additional inactivation mechanisms are required to produce spatial specificity of PKA activity.     

Effects of different cryopreservation methods on post-thaw culture conditions of in vitro produced bovine embryos

The aim of this work was to evaluate the effect of cryopreservation protocols on subsequent development of in vitro produced bovine embryos under different culture conditions. Expanded in vitro produced blastocysts (n = 600) harvested on days 7-9 were submitted to controlled freezing [slow freezing group: 10% ethylene glycol (EG) for 10 min and 1.2°C/min cryopreservation]; quick-freezing [rapid freezing group: 10% EG for 10 min, 20% EG + 20% glycerol (Gly) for 30 s]; or vitrification [vitrification group: 10% EG for 10 min, 25% EG + 25% Gly for 30 s] protocols. Control group embryos were not exposed to cryoprotectant or cryopreservation protocols and the hatching rate was evaluated on day 12 post-insemination. In order to evaluate development, frozen-thawed embryos were subjected to granulosa cell co-culture in TCM199 or SOFaa for 4 days. Data were analyzed by PROC MIXED model using SAS Systems for Windows?. Values were significant at p < 0.05. The hatching rate of the control group was 46.09%. In embryos cultured in TCM199, slow freezing and vitrification group hatching rates were 44.65 ± 5.94% and 9.43 ± 6.77%, respectively. In embryos cultured in SOFaa, slow freezing and vitrification groups showed hatching rates of 11.65 ± 3.37 and 8.67 ± 4.47%, respectively. In contrast, the rapid freezing group embryos did not hatch, regardless of culture medium. The slow freezing group showed higher hatching rates than other cryopreservation groups. Under such conditions, controlled freezing (1.2°C/min) can be an alternative to cryopreservation of in vitro produced bovine embryos.     

The role of fluoride on the process of titanium corrosion in oral cavity

Titanium is known to possess excellent biocompatibility as a result of corrosion resistance, lack of allergenicity when compared with many other metals. Fluoride is well known as a specific and effective caries prophylactic agent and its systemic application has been recommended widely over recent decades. Nevertheless, high fluoride concentrations impair the corrosion resistance of titanium. The purpose of this article is to summarize the current data regarding the influence of fluoride on titanium corrosion process in the last 5?years. These data demonstrate noxious effects induced by high fluoride concentration as well as low pH in the oral cavity. Therefore, such conditions should be considered when prophylactic actions are administrated in patients containing titanium implants or other dental devices.     

New hypotheses for the binding mode of 4- and 7-substituted indazoles in the active site of neuronal nitric oxide synthase

Taking into account the potency of 4- and 7-nitro and haloindazoles as nNOS inhibitors previously reported in the literature by our team, a multidisciplinary study, described in this article, has recently been carried out to elucidate their binding mode in the enzyme active site. Firstly, nitrogenous fastening points on the indazole building block have been investigated referring to molecular modeling hypotheses and thanks to the in vitro biological evaluation of N(1)- and N(2)-methyl and ethyl-4-substituted indazoles on nNOS. Secondly, we attempted to confirm the importance of the substitution in position 4 or 7 by a hydrogen bond acceptor group thanks to the synthesis and the in vitro biological evaluation of a new analogous 4-substituted derivative, the 4-cyanoindazole. Finally, by opposition to previous hypotheses describing NH function in position 1 of the indazole as a key fastening point, the present work speaks in favour of a crucial role of nitrogen in position 2.     

Synthesis, SAR, and preliminary mechanistic evaluation of novel antiproliferative N⁶,5'-bis-ureido- and 5'-carbamoyl-N⁶-ureidoadenosine derivatives

We have developed efficient methods for the preparation of N(6),5'-bis-ureidoadenosine derivatives and their 5'-carbamoyl-N(6)-ureido congeners. Treatment of 5'-azido-5'-deoxy-N(6)-(N-alkyl or -arylurea)adenosine derivatives (6a-d) with H(2)/Pd-C or Ph(3)P/H(2)O, followed by N-methyl-p-nitrophenylcarbamate gave N(6),5'-bis-ureido products 7a-d in 49-78% yield. Analogous derivatives in the 5'-carbamoyl-N(6)-ureido series were prepared by treatment of 2',3'-bis-O-TBS-adenosine (11) with N-methyl-p-nitrophenylcarbamate followed by acylation with appropriate isocyanates which gave 13a-d in 45-69% yield. A more versatile route for obtaining potentially vast libraries of compounds from both series was achieved by treatment of 5'-N-methylureido- or 5'-N-methylcarbamoyladenosine derivatives with ethylchlorformate to give N(6)-ethoxycarbonyl derivatives (9 and 14) in 55-63% yields, respectively. Simple heating of 9 or 14 in the presence of primary alkyl- or arylamines gave the corresponding N(6),5'-bis-ureido- or 5'-carbamoyl-N(6)-ureidoadenosine derivatives in good yields (33-72% and 39-83%; 10a-e and 15a-e, respectively). Significant antiproliferative activities (IC(50)≈4-10 μg/mL) were observed for a majority of the N(6),5'-bis-ureido derivatives, whereas the 5'-carbamoyl-N(6)-ureido derivatives were generally less active (IC(50) >100 μg/mL). A 2',3'-O-desilylated derivative (5'-amino-5'-deoxy-5'-N-methylureido-N(6)-(N-phenylcarbamoyl)adenosine, 16) was shown to inhibit binding of 16 of 441 protein kinases to immobilized ATP-binding site ligands by 30-40% in a competitive binding assay at 10 μM. Compound 16 was also shown to bind to bone morphogenetic protein receptor 1b (BMPR1b) with a Kd=11.5 ± 0.7 μM.     

New cytogenetic aberrations found in a case of aggressive retinoblastoma

We describe a case of retinoblastoma with an atypical presentation and previously unreported cytogenetic aberrations. A 19-month-old girl with left intraocular retinoblastoma was treated with enucleation and chemotherapy. The disease showed aggressive evolution within a short period between diagnosis and relapse. Eight months after diagnosis, a new large tumor was present in the orbit of the right eye, with diffuse bone pain, pancytopenia and diffuse infiltration into the bone marrow and the central nervous system. The child did not respond to treatment and died. Cytogenetic studies made with G-banding, FISH and SKY analysis showed chromosomal aberrations commonly associated with retinoblastoma, including del(13q), i(6p), +1, and monosomy 16, along with others that had not been reported previously, including dup(5q), dic(15;22) and add(14q). The new chromosomal aberrations may be related to the aggressiveness of the disease in this case.     

Effects of sow nutrition during gestation on within-litter birth weight variation: a review

The increasing demand for efficiency in pork production requires great specialization of all sectors involved in this activity. In this context, the development of strategies that could reduce undesirable traits related with negative effects on piglet survival and postnatal growth and development are essential for the pig industry. Currently, special attention is given to variation in birth weight, as some evidences suggest an increased within-litter birth weight variation in modern sows. This variation has been shown to be associated with preweaning mortality, variable weights at weaning and deteriorated growth performance, which results in economic losses and lower efficiency. Therefore, understanding the factors that can influence the events that occur during gestation and that have an impact on the fetal growth and development are important to achieve better efficiency and also to develop strategies that can be used to achieve increased within-litter uniformity of piglet birth weight. This study concludes that even at a given placental size, fetal growth may vary because of differences in placental vascularization and efficiency. Feeding extra feed or energy during late gestation only marginally improves birth weight, and positive effects are not consistent between different studies. The detrimental effects of protein restriction on fetal growth during early gestation may be due to altered placental and endometrial angiogenesis and growth, which leads to a reduction in placental-fetal blood flow, nutrient supply from mother to the fetuses and ultimately to fetal growth retardation. The number of studies that attempted to influence within-litter birth weight variation by means of sow nutrition during gestation is limited. Therefore, more research concerning sow nutrition during gestation associated with the provision of balanced diets to meet requirements of the sows and fetuses are still required. This knowledge may subsequently provide starting points for the design of nutritional strategies that can influence within-litter birth variation.     

Employment of a noninvasive magnetic method for evaluation of gastrointestinal transit in rats

ABSTRACT: AC Biosusceptometry (ACB) was previously employed towards recording gastrointestinal motility. Our data show a reliable and successful evaluation of gastrointestinal transit of liquid and solid meals in rats, considering the methods scarcity and number of experiments needed to endorsement of drugs and medicinal plants. ACB permits real time and simultaneous experiments using the same animal, preserving the physiological conditions employing both meals with simplicity and accuracy.