Microsporogenesis,Megasporogenesis and the Formation of Male and Female Gametophyte in Coix lacryma-jobi L.

The development of the anther wall follows the monocotyledonous type. During meiotic stages of prophase I, some cytoplasmic channels are observed on the walls between meiotic cells. which divide synchronously. Cytokinesis in the microspore mother cell is of the successive type and gives rise to iscbilateral tetrad. The cell wall between the generative cell and the vegetative cell in early stage shows PAS positive reaction. The mature pollen grain is of 3-celled type. The development of the female gametophyte follows the polygonum-type; the antipodal cells proliferate to form a multicellular tissue mass. Many starch grains are present in the central cell. The nucleus of the mature egg cell is located at the micropylar end; a great deal of starch grains are in the cytoplasm surrounding the nucleus, while vacuoles of various size distribute throughout its cytoplasm but are more and larger at the chalaza,1 end. The nucleus of the synergid cell is located at the micropytar end where a filiform apparatus is formed and many small vacuoles are present at the chalazal part.     

Isoelectrofocusing Electrophoretic Analysis on Soluble Protein of Germinated Embryos and Young Shoots from Different Cytoplasmic Male Sterile Lines and Their Maintainers in Wheat

The soluble proteins of germinated embryos and young shoots in Wheat were studied by means of isoelectrofocusing (IEF) electrophoresis. The materials used were three species of cytoplasmic male-sterile (CMS) lines (Type E, T and A) and their maintainers. The protein quantity of pI 4. 9 in male-fertile materials is higher than the corresponding male-sterile ones; the protein of pI 6.85 is probably the result of gene expression in Timopheevi cytoplasm; the protein of pI 7.6 is a typical band of Jinfeng male-sterile line. Evident differences on soluble protein chromatograms of IEF electrophoresis were observed both in germinated embryos and young shoots which were from different kinds of CMS line, these differences could be used as indexes identifying various CMS lines.     

Biosynthesized nanosilver as anti-oxidant,anti-apoptotic and anti-inflammatory agent against Plasmodium chabaudi infection in the mouse liver

In recent years, the use of plant-mediated nanoparticle synthesis to combat infectious diseases has become increasingly significant. Malaria is one of the world's most infectious diseases caused by Plasmodium species. The antioxidant, anti-apoptotic, and anti-inflammatory properties of nanosilver biosynthesized from Indigofera oblongifolia leaf extracts (NS) against Plasmodium chabaudi infection of the mouse liver were investigated in this research. Male mice were infected with P. chabaudi infected erythrocytes then treated with NS for 7 days. The parasitemia was suppressed by approximately 24, 28, 47 and 75% on days 4, 5, 6 and 7 postinfection, respectively after treatment of mice with NS. Also, NS was able to regulate the leucocytes count and the IL1β and TNF-α-mRNA expression in mice. Ns could increase the antioxidant activity in liver of mice and was able to regulate the apoptotic genes, Bcl2 and Casp3. We showed that NS has antioxidant, anti-apoptotic, and anti-inflammatory properties when it was used to treat the livers of mice infected with P. chabaudi.     

Male infertility is not liked with HSF1, HSF2 and UBE2I gene polymorphisms among Indian subjects

We analysed the polymorphisms at rs78202224 (C/A) for HSF1 gene, rs139496713 (C/T) and rs45504694 (C/A) for HSF2 gene and rs116868327 (G/A) for UBE2I gene in 547 infertile cases (non-obstructive azoospermia = 464, asthenozoospermia = 83) and 419 proven fertile controls of similar age group and ethnicity. SNP genotyping was done using AgenaMassARRY platform (Agena Bioscience, CA). Common, heterozygous, rare genotypes and allelic frequencies were analysed using dominant, recessive and co-dominant models. Data shows no significant association between HSF1, HSF2 polymorphisms and male infertility. However, under dominant (GG vs GA+AA) and co-dominanat (GG vs GA) model, polymorphism at the rs116868327 (G/A) locus in UBE2I gene was found to be linked with asthenozoospermia in males with a significant odd-ratio of 6.91 (confidence interval at 95% was 1.52-31.46; p=0.017). Moreover, frequency of rare allele was higher (2.4%) compared to controls (0.4%). Thus, this data showed a significant risk of developing asthenozoospermic condition in males (Odds ratio= 6.75; Confidence interval at 95%= 1.50-30.49; P= 0.018]. Hence, more number of genotyping studies along with the functional assay in multiple cohorts is needed to validate potential variants associated with male infertility.     

Could leptin be responsible for the reproductive dysfunction in obese men?

Low sperm concentration, increased fraction of morphologically abnormal sperm, and raised levels of markers of oxidative stress are often reported in the seminal plasma of infertile obese males. The precise reason for changes remains unknown. This short review summarises evidence from human and animal studies linking leptin to the reproductive dysfunction reported in obese males and presents a possible mechanism for this based on the available data in the literature. Serum leptin concentrations correlate positively with body fat mass but its precise link to semen abnormalities reported in obese males has yet to be conclusively established. Decreased sperm concentration, increased fraction of morphologically abnormal sperm and increased markers of oxidative stress have been reported following six weeks of daily leptin treatment to normal weight rats. In addition, decreased expression of endogenous antioxidant enzymes and increased expression of respiratory chain enzymes noted in the testes of leptin treated rats increases the propensity to oxidative stress. Besides that, leptin’s interference with histone to protamine transition in the DNA of sperm increases the susceptibility of sperm to free radical attack and may explain the often reported higher DNA fragmentation index in sperm of obese males. Concurrent supplementation of melatonin, a natural anti-oxidant, to these rats prevents the effects of leptin. The role of leptin in obesity-related reproductive dysfunction has to be considered seriously and these effects of leptin might involve increased oxidative stress.     

The sterile release method for population control with interspecific competition

A differential equations model of competing species with the release of sterile individuals of one of the species is examined. The system is found to have two positive steady states for certain parameter values; one of these is stable and the other is unstable. The system is quite resilient around the stable steady state. The release of steriles causes the nontarget species to increase in numbers. There exists a value of the release rate above which the pest species collapses to extinction. The existence of the competitor species assists the sterile release program since the pest equilibrium at any release rate is lower with the competitor species present than without it; in addition the release rate required to cause collapse of the pest species is lower with the competitor species present than without it. The effects of the parameters on the ease of eradication were examined. It was found that the ideal competitor species should have a high rate of increase, a large carrying capacity and exert strong competitive depression on the pests. The ideal pest would have a low rate of increase, a low carrying capacity and be a poor competitor.     

Purification and characterization of liver microsomal cytochrome P-450 from untreated male rats

Different forms of cytochrome P-450 from untreated male rats were simultaneously purified to homogeneity using the HPLC technique. The absorption maximum, molecular weight, NH₂-terminal sequence and catalytic activity of them were determined. The NH₂-terminal sequences of six forms of cytochrome P-450 (designated P450 UT-1, UT-2, UT-4, UT-5, UT-7 and UT-8) indicate that these cytochrome P-450 isozymes are of different molecular species. The hydrophobicity values of the NH₂-terminal sequences of P450 UT-1 and P450 UT-8 were lower than that of other forms. P450 UT-8 has the highest molecular weight, 54 000, of the six forms of P-450. P450 UT-2 was active in demethylation of benzphetmaine, 450 UT-4 was active in the metabolism of 7-ethoxycoumarin and p-nitroanisole. P450 UT-1 ad P450 UT-2 were active in the 2α- and 16α-hydroxylation of testosterone, whereas P450 UT-4 was active in the 6β-, 7α- and 15α-hydroxylation of the same steroid. We believe that P450 UT-1, P450 UT-7 and P450 UT-8 are as yet unrecognized forms of cytochrome P-450.     

The 1999 and 2010 WHO reference values for human semen analysis to predict sperm DNA damage: A comparative study

Standard semen parameters are often used to predict male fertility, but whether the 2010 World Health Organization (WHO 2010) thresholds are better predictors than the 1999 thresholds has not been investigated. In this study, we addressed this issue using sperm DNA fragmentation (SDF) as a marker of male fertility in 134 subfertile male individuals. To compare the predictive value of the 1999 thresholds with the 2010 cutoffs, the Youden indices (YIs) of all possible thresholds were calculated using receiver operating characteristic (ROC) curves and compared to each other and to the respective YIs of optimal thresholds. We found that the area under the ROC curves of progressive motility and vitality was the highest among standard semen parameters, and that the YI of both parameters from the 2010 manual was comparable to the respective optimal YIs. In contrast, the threshold of sperm concentration and total sperm number from both WHO recommendations demonstrated low YIs, with substantial differences to the respective optimal YIs. The YIs of normal morphology cutoffs from both WHO manuals were slightly different from each other and from the respective optimal YIs. In conclusion, the 2010 thresholds for progressive motility and vitality are superior to the 1999 thresholds in predicting SDF, whereas the cutoff value of sperm concentration, total sperm number and normal morphology may need further revisions to increase their accuracy.     

Effects of electrical stimulation before or after in vitro fertilization on sperm penetration and pronuclear formation of pig oocytes

The effects of exposure of pig oocytes to an electrical pulse on sperm penetration and pronuclear formation were determined before or after in vitro fertilization (IVF). After in vitro maturation (IVM) or after collection from oviducts of unmated gilts, pig oocytes either were not exposed or were exposed to an electrical pulse (a 10 sec pulse at 4.0 V mm^?1 AC followed by a 30 μsec pulse at 120 V mm^?1 DC), followed 30 min later by IVF. The incidence of male pronuclear formation of both IVM and in vivo-matured oocytes at 12 hr after insemination was decreased from 59% and 100%, respectively, to 2% and 36%, respectively, by the electrical pulse, but the penetration rates (88–100%) and polyspermic rates (79–100%) were not affected by exposure to an electrical pulse. Similarly, when pig IVM oocytes were exposed to an electrical pulse at 6 hr after insemination, electrical activation did not decrease penetration rates (93% vs. 90%), polyspermic rates (83% vs. 91%), or number of spermatozoa in penetrated oocytes (4.0 ± 0.5 vs. 4.6 ± 0.5) but did decrease the rate of male pronuclear formation from 58% to 18%. When oocytes were examined at 6 hr after insemination, 75% of them had been penetrated and resumed meiotic progression, but all sperm heads in penetrated oocytes were fully condensed or only partially decondensed. The percentage of penetrated eggs with multiple female pronuclei was increased when oocytes were exposed to an electrical pulse in all experimental series. In summary, electrical activation of pig oocytes before or just after IVF does not prevent sperm penetration but does inhibit male pronuclear formation and increases the formation of multiple female pronuclei. © 1993 Wiley-Liss, Inc.