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关键词： Cryopreservation   Oocyte   Cryotech (R)   Mitochondria   Redox state  

摘要： The aim of the present study was to evaluate the effect of vitrification on morphological, biochemical and functional parameters of matured bovine oocytes at different recovery times. To this end, matured bovine oocytes were vitrified using the Cryotech (R) kit (a minimum-volume system) and then incubated in maturation medium for different post-warming durations (0 h, 3 h or 21 h). Morphology, viability and biochemical parameters were assessed at each time point mentioned above and the recovery of the metaphase plate was analyzed at 2 h, 3 h and 4 h post-warming. The vitrification-warming process did not affect the viability or morphology of oocytes at any time point. However, the recovery of the metaphase plate occurred mostly between 3 and 4 h rather than at 2 h after warming (P < 0.05). Both control and vitrified-warmed oocytes showed changes in cytosolic oxidative activity, quantification of active mitochondria, reactive oxygen species (ROS) levels and redox status at the different time points studied (P < 0.05). However, differences between control and vitrified-warmed oocytes were found only in the quantification of active mitochondria and ROS production (P < 0.05). Finally, in vitro fertilization and embryo culture were carried out as functional studies to establish whether vitrification-warming affected oocyte competence, and a significant decrease was found both in the cleavage rate and embryo development (P < 0.05). We concluded that major improvements in oocyte vitrification, at list with Cryotech (R) kit, are still needed to avoid variations in oocyte metabolism which could contribute to the reduction in the developmental competence of bovine oocytes. (C) 2019 Elsevier Inc. All rights reserved.

关键词： Borassus aethiopum Mart   Fresh palm sap   Biochemical and microbiological composition   Nutritional   Burkina Faso  

摘要： The palmyra palm Borassus aethiopum Mart. grow wild and gives natural stands in several localities of central-eastern and eastern regions of Burkina Faso. This work aimed to determine the nutritional, biochemical and microbiological composition of fresh palm sap from B. aethiopum Mart. during the first 4 days of tapping. The composition of palm sap was carried out by HPLC and standard methods. The sap collected during the first 4 days were sugary and contained less alcohol. The mean values of the pH, total and reducing sugars content were 4.84 +/- 0.5, 11.36 +/- 3.97 and 2.93 +/- 1.22% w/v respectively. Sucrose, glucose, fructose and Vitamin C values were 6.75% w/v, 4.99 g/L, 7.09 g/L, 8.93% w/v respectively. Galactose and xylose were not detected. Soluble proteins, arabinose, phenols and ethanol were present in low concentration. Calcium, potassium, magnesium and ammonium were present in palm sap with highest potassium content (13.26 g/L). Lactate (2.41 +/- 0.86 g/L), succinate (2.49 +/- 1.46 g/L), acetate (0.01 +/- 0.006 g/L), malate (0.17 +/- 0.31 g/L), propionate (0.07 +/- 0.04 g/L), citrate (0.19 +/- 0.11 g/L), tartrate (0.08 +/- 0.09 g/L) and pyruvate (0.05 +/- 0.03 g/L) were detected in palm sap. The microbiological analysis of sap gave 1.23 +/- 1.01 x 10(8) cfu/mL for total aerobic flora, 7.27 +/- 1.19 x 10(5) cfu/mL for yeasts, 1.86 +/- 1.63 x 10(7) cfu/mL for lactic acid bacteria and 3.75 +/- 0.75 x 10(5) cfu/mL for acetic acid bacteria. The fresh sap from B. aethiopum presents good nutritional value and its consumption can help to improve dairy food intake of rural population. It can be used for the manufacture of various products like palm wine, syrups, sugars, functional foods, etc.

关键词： CKDu   NCP   BUN   Microalbumin   creatinine  

摘要： Background Chronic Kidney Disease of unknown etiology (CKDu) is prevalent in North Central Province (NCP) of Sri Lanka. Consumption of un-boiled dug well water has been identified as one of the causative factors. This in-vivo study was performed to investigate some of the suspected factors associated with the pathogenesis of CKDu mediated via ground water. Method Rats were given water, collected from high and low disease prevalent areas from the NCP of Sri Lanka and the results compared with those obtained from previously identified low disease prevalent area;Colombo. Blood Urea Nitrogen, creatinine, urinary microalbumin:creatinine ratio together with ALT and AST levels were analyzed and results were compared using one-way ANOVA and paired t-Test. Histopathology was analyzed using non-parametric method. Results Rats that ingested water from New Town Medirigiriya (NTM) from high disease prevalent NCP reported significantly elevated microalbumin:creatinine ratios compared to other water sources after 8 months, whilst boiled water from NTM had been able to significantly reduce it. Histopathological findings after the 14 months experimental period revealed significantly high tubular lesion index in rats that ingested water from NCP compared to Colombo. Rats that ingested water from high disease prevalent Divuldamana (DD) from NCP showed the highest kidney lesion index though the fluoride content was relatively low in this area compared to other water sources from high disease prevalent NCP. Rats that ingested boiled and un-boiled water from NTM also developed severe lesions whilst the group from Colombo reported the lowest. Low disease prevalent area from NCP, Huruluwewa (HW) also reported elevated liver enzymes and altered renal histopathology. Association of Na+:Ca2+ ratio in the disease progression was not reflected by the current study. Compared to Colombo, high fluoride, calcium and sodium contents were observed in water from high disease prevalent areas. All the w

关键词： Apple sunburn   Early detection strategies   Molecular mechanisms response   Hormonal control   Genomic information   Transcriptomic challenges  

摘要： Climate change negatively influences many human activities and one of the most affected is agriculture. In the apple industry, water availability, elevated temperatures and altered phenology will transform fruit production in traditional growing regions. Extended periods of intense solar radiation and high temperatures during the growing season cause problems in fruit quality increasing losses and reducing sustainability and profitability. Photooxidative and heat stress stimulate sunburn development on apple fruit in the field growing under increasingly stressful conditions. In particular, apples growing in semi-arid conditions are frequently exposed to high solar irradiance and elevated temperature during the growing season that promote the development of sun-related skin disorders. Furthermore, regions that have traditionally not faced sunburn pressure may begin to experience losses in this area. Apple cultivars differ in their susceptibility to sun damage, which is evidenced, in part, by the timing of symptom development and severity. Some studies attribute genotypic variation to physiological and morphological differences while others do to antioxidant-related metabolic differences between them. Here, we discuss the physiological and molecular progress and gaps in knowledge of sunburn damage and the development of sunburn resistance in apple fruit. This information will help develop stronger sunburn mitigation strategies and enhance breeding efforts to address challenges associated with sunburn in apple production.

关键词： GTPase-activating protein (GAP)   dimerization   Ras protein   GTPase Kras (KRAS)   cell signaling   cancer   mitogen-activated protein kinase pathway   neurofibromin   NF1  

摘要： Neurofibromin is a tumor suppressor encoded by the NF1 gene, which is mutated in Rasopathy disease neurofibromatosis type I. Defects in NF1 lead to aberrant signaling through the RAS?mitogen-activated protein kinase pathway due to disruption of the neurofibromin GTPase-activating function on RAS family small GTPases. Very little is known about the function of most of the neurofibromin protein;to date, biochemical and structural data exist only for its GAP domain and a region containing a Sec-PH motif. To better understand the role of this large protein, here we carried out a series of biochemical and biophysical experiments, including size-exclusion chromatography?multiangle light scattering (SEC-MALS), small-angle X-ray and neutron scattering, and analytical ultracentrifugation, indicating that full-length neurofibromin forms a high-affinity dimer. We observed that neurofibromin dimerization also occurs in human cells and likely has biological and clinical implications. Analysis of purified full-length and truncated neurofibromin variants by negative-stain EM revealed the overall architecture of the dimer and predicted the potential interactions that contribute to the dimer interface. We could reconstitute structures resembling high-affinity full-length dimers by mixing N- and C-terminal protein domains in vitro. The reconstituted neurofibromin was capable of GTPase activation in vitro, and co-expression of the two domains in human cells effectively recapitulated the activity of full-length neurofibromin. Taken together, these results suggest how neurofibromin dimers might form and be stabilized within the cell.

关键词： Arsenic   Salinity   Quinoa   Phytostabilization   ROS   Antioxidants  

摘要： Soil salinity and arsenic (As) contamination are serious environmental problems. To investigate the effects of salinity on As uptake and physiological and biochemical attributes of quinoa (Chenopodiwn quinoa Willd.), a hydroponic experiment was performed. One-month old healthy plants of two quinoa genotypes;Vikinga and A7 were transplanted in plastic tubs containing half strength Hoagland's nutrient solution. Plants were exposed to different levels of As (0, 150 and 300 mu M), salinity (0, 150 and 300 mM) and their combinations (150 mu M As + 300 mM NaCI;300 mu M As + 300 mM NaCl) for five weeks. Results revealed that combined application of salinity and As caused more pronounced reduction in growth, chlorophyll contents and caused more oxidative damage in both quinoa genotypes. Under combined application of salinity and As, Na+ concentration was increased whereas As content was decreased in plant tissues. Quinoa genotype A7 was more tolerant than Vikinga against salinity, As and their combination perhaps because of less uptake of toxic ions and higher activities of antioxidant enzymes (SOD, CAT, POD). Bioconcentration factor (BCF), translocation factor (TF) and tolerance index (TI) indicated that genotype A7 can be successfully employed for phytostabilization of As contaminated saline soils.

关键词： Common bottlenose dolphin   Pregnancy   Gestation   Biochemistry   Hematology   Tursiops truncatus  

摘要： The physiological demands of pregnancy inevitably result in changes of both biochemical and hematological parameters as the fetus develops. Alterations in blood parameters have been observed to shift according to both trimester and species, to support fetal physiological needs and maternal basal requirements. Establishing normal reference ranges for each stage in gestation is important to facilitate diagnosis of underlying health concerns and prevent over-diagnosing abnormalities. Despite bottlenose dolphins (Tursiops truncatus) being one of the most highly studied cetaceans, the blood profile changes occurring as a result of pregnancy have not been previously described. A retrospective analysis was performed from blood samples obtained from 42 successful pregnancies from 20 bottlenose dolphins in a managed population over 30 years. Samples were compared to non-pregnant states and among trimesters of pregnancy. Blood profile fluctuations occurred throughout gestation, however significant alterations predominantly occurred between the 2nd and 3rd trimester. Hematological changes from the 2nd to the 3rd trimester included a decrease in lymphocytes, decrease in platelet count, and hemoconcentration with increased hematocrit and hemoglobin. Biochemical changes in the 3rd trimester included significant reductions in ALKP (alkaline phosphatase), ALT (alanine aminotransferase) and AST (aspartate aminotransferase) with significant increases observed in albumin, globulins, total protein, cholesterol, triglycerides and CO2. It's important to note that despite significant shifts occurring between the 2nd and 3rd trimester, there was no significant change in platelets, hematocrit, hemoglobin, lymphocytes or CO2 between non-pregnant and 3rd trimester blood samples. The normal reference ranges for each trimester established herein, will enable future identification of abnormalities occurring during pregnancy and help improve our understanding of factors potentially influencing a