Sperm cryopreservation of tiete tetra Brycon insignis (Characiformes): effects of cryoprotectants,extenders, thawing temperatures and activating agents on motility features

The aim of this study was to test the effects of cryoprotectants [dimethyl sulphoxide (DMSO) and methylglycol], extenders (0.9% NaCl, 5% glucose, Beltsville Thawing Solution^? and Merck III^?), thawing temperatures (30 and 60 °C) and activating agents (0.29% NaCl and 1% NaHCO₃) on the cryopreservation process of tiete tetra Brycon insignis sperm. Sperm was loaded in 0.5 mL straws, frozen in nitrogen vapour at ?170 °C and stored in liquid nitrogen. Post‐thaw sperm quality was evaluated in terms of subjective motility rate, quality motility score (0=no movement; 5=rapidly swimming spermatozoa), duration of motility and vitality (eosin–nigrosin staining). Post‐thaw sperm motility rate was greater in methylglycol (76–88%), compared with DMSO (23–59%). In general, the highest quality motility scores were observed when sperm was thawed at 30 °C and triggered in 1% NaHCO₃ (3.5–4.3). Duration of motility was longer when triggered in 1% NaHCO₃ (95–120 s) compared with 0.29% NaCl (69–107 s). Sperm vitality was not affected by any of the parameters tested and varied from 51% to 69% intact sperm. Brycon insignis sperm frozen in methylglycol combined with any of the extenders tested and using the methods described above yields motility above 57% and that should last long enough to fertilize oocytes.     

Winter × spring wheat hybridization - a promising avenue for yield enhancement

Introgression of the winter gene pool into spring wheat is being considered as one of the strategies to break through the yield plateau. However, little information is available on the combining ability of these two important but distinct groups of wheats in Indian conditions. Therefore, the present study was undertaken to determine the combining ability and gene action of yield and yield attributes in winter × spring wheat crosses. Seventy F₁ progenies developed by 14 winter and five spring wheat lines using a line × tester design were evaluated, along with their parents, for yield and yield attributes in a randomized complete block design under field conditions. The mean squares for all the characters studied showed highly significant differences. The mean squares due to female × male interactions were significant for all the characters studied except for grains per ear and grain weight per ear. Additive genetic effects were found to play a key role in controlling the expression of days to heading, plant height and spikelets per ear.‘MV 19’ and ‘Stepniak’/‘Karvuna’ among winter and ‘PBW 65’ among spring wheats were good general combiners for most of the yield attributes studied. The estimates for specific combining ability effects suggested that, although general combining ability (GCA) effects of most winter wheats are either average or poor, their combination can give desirable genotypes with spring wheat parents possessing a high GCA.     

Development of an appropriate procedure for estimation of RUSLE EI30 index and preparation of erosivity maps for Pulau Penang in Peninsular Malaysia

Pluviographic data at 15 min interval from 6 stations in Pulau Penang of Peninsular Malaysia were used to compute rainfall erosivity factor (R) for the revised universal soil loss equation (RUSLE). Three different modelling procedures were applied for the estimation of monthly rainfall erosivity (EI₃₀) values. While storm rainfall (P) and duration (D) data were used in the first approach, the second approach used monthly rainfall for days with rainfall ≥ 10 mm (rain₁₀) and monthly number of days with rainfall ≥ 10 (days₁₀). The third approach however used the Fournier index as the independent variable. Based on the root mean squared error (RMSE) and the percentage error (PE) criteria, models developed using the Fournier index approach was adjudged the best with an average PE value of 0.92 and an average RMSE value of 164.6. Further, this approach was extended to the development of a regional model. Using data from additional sixteen stations and the Fournier index based regional model, EI₃₀ values were computed for each month. ArcView GIS was used to generate monthly maps of EI₃₀ values and also annual rainfall erosivity (R). The rainfall erosivity factor (R) in the region was estimated to vary from 9000 to 14,000 MJ mm ha^− 1 h^− 1 year^− 1.     

Postindustrial melanism in the peppered moth

New data show the geographical pattern of frequency of the melanic morph carbonaria of the peppered moth, Biston betularia, in 1983-84. These frequencies are compared with data from 1952 to 1970. After 20 years of smoke control, the area of high melanic frequency has contracted to the northeast. The change indicates a disadvantage to carbonaria of about 12 percent compared with 20 years ago. Computer simulations, which do not include the assumption of heterozygote advantage, provide a good match to the surface for the period 1952 to 1970, and also the 1983-84 surface. Experiments on visual predation have been criticized as giving unrepresentative estimates of selection but they permit satisfactory simulations to be made.     

Requirement for DARPP-32 in progesterone-facilitated sexual receptivity in female rats and mice

DARPP-32, a dopamine- and adenosine 3',5'-monophosphate (cAMP)-regulated phosphoprotein (32 kilodaltons in size), is an obligate intermediate in progesterone (P)-facilitated sexual receptivity in female rats and mice. The facilitative effect of P on sexual receptivity in female rats was blocked by antisense oligonucleotides to DARPP-32. Homozygous mice carrying a null mutation for the DARPP-32 gene exhibited minimal levels of P-facilitated sexual receptivity when compared to their wild-type littermates. P significantly increased hypothalamic cAMP levels and cAMP-dependent protein kinase activity. These increases were not inhibited by a D1 subclass dopamine receptor antagonist. P also enhanced phosphorylation of DARPP-32 on threonine 34 in the hypothalamus of mice. DARPP-32 activation is thus an obligatory step in progestin receptor regulation of sexual receptivity in rats and mice.     

Effect of wheat bran supplementation on blood sugar,glycosylated protein and serum lipids in NIDDM subjects

Wheat bran supplementation (11 gm per day) was carried out for a period of two months in 30 maturity onset diebetics. The efficacy of bran supplementation was monitored by measuring the fasting and 2 h post prandial blood sugar levels, glycosylated serum protein levels, glycosylated albumin levels and serum lipid and lipoprotein cholesterol levels. The results indicated a transient reduction in fasting and 2 h post prandial blood sugar levels after one month's bran therapy. No appreciable changes in the serum glycosylated protein levels, glycosylated albumin levels, serum lipids and lipoprotein cholesterol levels were observed during the period of supplementation.Abbreviations TC total cholesterol - HDL-C high density lipoprotein cholesterol - LDL-C low density lipoprotein cholesterol - VLDL-C Very low density lipoprotein cholesterol - TG triglycerides - PL phospholipids - FFA free fatty acids - G-Alb glycosylated albumin - GSP glycosylated serum proteins - NIDDM Non Insulin Dependent Diabetes Melitus     

Prevalence of rotavirus A infection and the detection of type G3P[11] strain in ruminants in Yobe state,Nigeria

Rotaviruses have a worldwide distribution and the infection is associated with diarrhea in young of ruminants as well as children. However, limited data exist on its prevalence and types in Yobe state, Nigeria. Detection of rotavirus A and types in ruminant population in Yobe state was the aim of the study. A total of 470 diarrheic fecal samples were collected and tested for rotavirus and types using serology and molecular techniques respectively. A prevalence rate of 2.98% (14/470) was found in the three species with specific rates of 2.9% (6/202), 3.8% (6/158), and 1.8% (2/110) in goat, sheep, and cattle respectively. The prevalence rates of 3.6% (12/331), 1.2% (1/84), and 1.8% (1/55) were for those aged < 1–3, 4–6, and 7–9 months old, respectively, while 4.9% (9/185) and 1.7% (5/285) were in males and females respectively. Rotavirus genes VP7 and VP4 were detected in 2 (14.3%) out of the 14 ELISA-positive samples while deduced amino acid sequences of the major variable regions revealed the genes to belong to types G3P[11] strain. Significant association was found between the infection and sex (P < 0.05) unlike in the species and age groups of the ruminants. The circulation of rotavirus virus in ruminants and type G3P[11] in cattle has been confirmed in the study. Hence, there is a need for continuous surveillance, awareness campaign, and assessment of the economic losses and public health implications of rotavirus infection in Nigeria.

     

鸽毛滴虫外泌体的分离鉴定及蛋白质谱分析

旨在研究鸽毛滴虫是否分泌外泌体及虫源外泌体的蛋白组成和功能,为探索外泌体在鸽毛滴虫寄生过程中的作用奠定基础。采集鸽毛滴虫感染个体口腔及咽部病灶处样本,进行分离培养及纯化,使用显微镜鉴定虫体形态,提取DNA并比对其序列,确定培养物是否为鸽毛滴虫虫株;通过对培养液上清进行超速离心,透射电子显微镜、Western blot技术和纳米颗粒追踪分析（nanoparticle tracking analysis,NTA）鉴定培养液上清中是否含有虫源外泌体;最后通过Label-free技术分析虫源外泌体的蛋白质谱表达。结果显示,虫体具有明显的毛滴虫形态及特征,与鸽毛滴虫ITS1/5.8S/ITS2基因比对率达98%。从虫体培养液中提取的囊泡经透射电子显微镜观察具有明显的茶托样结构;NTA结果显示,粒径集中于125.1 nm,峰值粒径为132.3 nm,占比99.3%;CD63和TSG101等外泌体标记蛋白的条带明显,表明提取物为外泌体。质谱结果显示,烯醇酶、3-磷酸甘油醛-脱氢酶、磷酸甘油酸变位酶和延伸因子为表达量较高的蛋白质。GO功能注释显示外泌体蛋白富集到细胞内和胞浆等细胞组分,发挥GTP连接和GTP酶活性功能,参与小GTPase介导的信号转导与糖酵解等过程。KEGG通路富集表明,虫源外泌体蛋白主要富集于代谢途径、糖酵解/糖异生、抗生素的生物合成和次级代谢产物的生物合成等通路。本研究发现鸽毛滴虫可以分泌外泌体,并对虫源外泌体进行蛋白质谱分析,提示虫源外泌体中的蛋白质在寄生虫的能量代谢、信号转导及生物合成等过程中发挥重要作用。