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Reactive oxygen species ( ROS) are required for cellular functioning and are controlled by anti-oxidants. The ROS influence the follicles, oocytes, endometrium, and their environment. The luteinizing hormone surge initiates a massive recruitment of ROS that modulates major reproductive functions namely, oocyte maturation, ovarian steroidogenesis, corpus luteal function, and luteolysis. The anti-oxidant system balances ROS generation and maintains the cellular functions. Both enzymatic and non-enzymatic anti-oxidants namely, vitamins and minerals are present in the follicles and protect the oocytes from the damaging effects of ROS. The overproduction of ROS leads to oxidative stress that affects the quality of oocytes and subsequent anovulation. Although researchers have tried to establish the role of ROS and anti-oxidants in oocyte development, still this aspect needs to be revisited. This review discusses the importance of the ROS and anti-oxidant balance that is required for the development and maturation of oocytes. There are increasing data on the activity of ROS and anti-oxidants in supporting oocyte development and maturation. However, extensive research is required to identify the safe physiological concentration and duration of both the ROS and anti-oxidants that are required to facilitate oocyte development and maturation during in vitro and in vivo conditions. [ABSTRACT FROM AUTHOR]

The aim of this study was to identify potential environmental controls of the asexual phases of reproduction by measuring the rates of asexual reproduction (budding and strobilation) and mortality in naturally occurring populations of Aurelia sp. scyphistomae at different spatial and temporal scales. The percentage cover, density of colonies of Aurelia sp. scyphistomae, and density of the population of two naturally occurring colonies of Aurelia sp. scyphistomae were examined over 2 years in southern Tasmania. Artificial substrates were also deployed to investigate colony dynamics when density dependent effects were reduced. Clear spatial and temporal differences in the population dynamics of the colonies were observed. Density dependent effects controlled budding and recruitment of new scyphistomae to the substrate when populations were dense and space limiting. In contrast, environmental controls of budding and strobilation were more apparent in a colony with significantly greater area of bare substrate and hence room for expansion. Water temperature and rainfall (as a proxy for salinity) were linked to changes in population size. Annual and seasonal differences in population dynamics were not observed in a colony limited by space but were apparent in a colony where space was not limited. When space was removed as a limiting factor by deploying artificial substrates, a seasonal environmental effect on the rate of growth of the colony was observed. These studies suggest that the growth, survival and reproduction of the sessile colonial phase of Aurelia sp. is regulated by a combination of density dependent factors and environmental conditions, which are consequently important to the formation of jellyfish blooms. [ABSTRACT FROM AUTHOR]

Objective:Cathepsins B (CB) and D (CD) belong to a family of protease felt to be important in tumor metastasis and invasion. It has been suggested that both enzymes play a role the progression of epithelial ovarian cancer and they have been investigated as potential biomarkers for ovarian cancer. Our objective was to determine if activity ratios of these two isoforms might enhance their usefulness as biomarkers.Methods:Ovarian cancer cell lines and snap-frozen archived tissue samples were sonicated and cathepsin activities were assayed fluorometrically with cathepsin-specific peptide substrates in combination with specific inhitors. Tissue specimens were divided into four groups: normal ovary, benign neoplasm, early-stage (I/II) cancer, and late-stage (III/IV) cancer. Median CB and CD activity and the ratio of CB to CD (CB/CD) were compared using the Wilcoxon rank sum test. Nonparametric Spearman correlation was used to determine associations between CA-125 and cathepsin activity. Logistic regression was used to test the association between cathepsin activity and malignancy.Results:In cell lines and tissue, CD activity remained relatively constant, while CB activity varied. CB activity was greatest in cancer tissue. Elevated serum CA-125 was associated with elevations in CB activity and CB/CD but not CD activity. Elevated CB activity and CB/CD as well as increasing CA-125 and age are all associated with malignancy. Multiple logistic regression shows that CB activity and age best predict malignancy status.Conclusions:CB activity is associated with invasive ovarian neoplasm. Our results do not suggest that the ratio of activity between CB and CD provides any additional information than CB activity alone. Both tissue CB activity and CB/CD activity ratios correlate with serum levels of CA-125; however there is no correlation between CD activity and CA-125. [ABSTRACT FROM PUBLISHER]

Focuses on the polychaete Platynereis dumerilii, a laboratory animal with spiralian cleavage, lifelong segment proliferation and a mixed benthic/pelagic life cycle. Collection, identification and breeding of the organism; Reproduction; Fertilization; Transformation of the larva.

Evaluates the impact of ascorbic acid doses during luteal phase in infertility treatment. Differences in clinical pregnancy rate and implantation rate of ascorbic acid; Details on the statistical logistic regression analysis between intake groups; Value of intake of vitamin C during luteal phase in infertility treatment.

An immunohistochemical study was made of cathepsin-D protein expression in each of the three main types of uterine cervical carcinoma (squamous carcinoma, adenosquamous carcinoma and adenocarcinoma) with particular reference to lymph node status and prognosis. Of the 61 cases, 54.1% showed cytoplasmic staining in more than 2.5% of tumour cells counted. Cathepsin-D expression was significantly higher in adenocarcinoma (mean -3.128) than in squamous carcinoma and adenosquamous carcinoma (mean −3.709, P=0.047 using logit transformation). Cathepsin-D had no prognostic value in any of the three tumour types. No relationship was found between cathepsin-D staining and lymph node status and there was no advantage in adding cathepsin-D values to lymph node status. These results suggest that immunostaining for cathepsin-D protein expression is unlikely to be of use as a prognostic marker. [ABSTRACT FROM AUTHOR]