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Redalyc.Predominant learning styles among pharmacy students at the Federal University of Paraná, Brazil
No full textImprovements to In Vitro Culture Media for Use in Bovine IVF Introduction
No full textAbstract In assisted reproduction of cattle the design and preparation of in vitro culture media has been instrumental in supporting the development of bovine oocytes and embryos. In vitro production (IVP) involves three main sequential steps: oocyte aspiration and in vitro maturation (IVM); in vitro fertilization (IVF); and in vitro culture (IVC) of early pre-implantation embryos. Research on IVC media has aimed to emulate the crucial elements that are present in the oviduct and uterus of female cattle by supplementing with protein and growth factors. As a result, IVP has proven a reliable methodology with an acceptable, if far from remarkable, blastocyst transfer rate of typically 40%. Moreover, the addition to media of defined extracts has gradually replaced that of fetal calf serum, leading to improved embryo viability and cryotolerance. Nevertheless, major advances in the composition of novel media that may facilitate a further increase of blastocyst rate have yet to be realized. Currently, there is considerable variation in the constituents of IVC media used in bovine assisted reproduction. Hence, significant innovations are required in order to not only achieve a greater success rate of IVP and to enhance the cryotolerance of bovine IVF-derived embryos but also to provide a defined IVC medium that may be recognized as a point of reference across the cattle breeding industry. This review examines the progress made to date in IVP to enhance embryo quality and points to future areas for investigation of a 'gold standard' IVC medium. This is a fully defined medium that supports consistently the attainment of a bovine IVP blastocyst rate similar to that achieved using a conventional medium supplemented with serum. Keywords: in vitro; IVF; Culture; Oocyte; Embryo; Blastocyst; Oviduct; Bovine The emerging trend in bovine assisted reproduction in recent years is that in vitro production (IVP) is increasingly overtaking multi-ovulation embryo transfer as the technology of choice in several countries, including Brazil In terms of embryo production costs, Galli et al. Despite such advantages over MOET, IVF remains a relatively inefficient process with blastocyst rates of around 40% An experimental approach has been successful in designing and generating various culture media based on an understanding of embryonic development in the female reproductive tract. Ovum-pick up technique allows the collection of bovine immature oocytes without the stimulation of gonadotropin hormones. These immature oocytes are then subjected to in vitro culture when they are influenced by various proteins and growth factors Development of Defined In Vitro Culture Media Bone morphogenetic protein 15 and fibroblast growth factor regulate the function of cumulus cells and increase embryo quality Annex Publishers | www.annexpublishers.com Currently, a dependency on the addition of sera continues since an innovative medium that provides a complete substitute for IVM has yet to be introduced for use in bovine IVP. Previously, Holm et al. [30] attained a high percentage of blastocysts from defined IVC medium; however, they concluded that FCS is essential for IVM. Lee et al. [37] developed a defined IVC medium by supplementing with non-essential and essential amino acids, but the blastocyst rates in this study did not reach above 40%. In addition, Neira et al. [16] designed a fully defined culture medium with the addition of a range of recombinant growth factors and cytokines; however, the blastocyst rates (ranging from 20 to 48%) that resulted from using the defined medium were no greater than those from non-defined culture medium supplemented with FCS. It may therefore be concluded that semi-defined in vitro media have been prepared successfully but that a fully defined in vitro medium remains to be formulated. Commensurate with the advancement in cryopreservation technology, a modification to IVC media is critical in order to improve the survival rates of IVP embryos post cryopreservation [40] reported a high mean pregnancy rate of 48.8% after the transfer of vitrified embryos. IVF technology provides the fertilization efficiency of sex-sorted sperm In order to improve the generation of bovine IVP embryos many attempts have been made to develop a suitably supportive IVC medium by the addition of various factors. However, production of bovine embryos by IVF remains sub-optimal. The elimination of batch-to-batch variations in IVP by replacing sera with a novel defined IVC medium has not been fulfilled. To an extent reduction of the use of sera in preparing defined media enhances the cryotolerance of IVP embryos during the cooling and warming processes. Nonetheless, at present the IVP blastocyst yield that is achieved using defined IVC media is unsatisfactory; consequently, the Indeed, the quality of IVP embryos is lower than that of in vivo counterparts The presence of serum in media is the main cause of increased lipid content of IVP embryos Sudano et al
5 Insulin-Like Growth Factor System in HIV/AIDS: A Structure Based Approach to the Design of New Therapeutics
Get PDFEssential Requirements for Data Security in the Context of Software Metrics
Get PDFAbstract By first raising and then dispelling seven common rules about metrics, this paper discusses the requirements and design constraints for a practical system to measure, report and improve data security. Data security will become business-as-usual after the implementation program is completed, but the need for measurement and continuous improvement will persist indefinitely. In other words, we needed more than conventional program or project management metrics. The need for data security metrics was much more pragmatic. Furthermore, intended to embed data security deeper into the academic/corporate culture, meaning that security awareness is an important component. We propose seven rules for data security in the context of Software metrics
Role of diestrus progesterone on endometrial function and conceptus development in cattle
Get PDFAbstract Successful growth and development of the post-hatching blastocyst and pregnancy establishment are a result of the interaction between a competent embryo and a receptive uterine environment. Progesterone (P4) plays a key role in reproductive events associated with establishment and maintenance of pregnancy through its action on the uterine endometrium. Elevated concentrations of circulating P4 in the immediate post-conception period have been associated with an advancement of conceptus elongation, an increase in interferon-tau production and higher pregnancy rates in cattle. The potential beneficial effects of exogenous P4 supplementation on fertility have been acknowledged for a long time but results of supplementation have been inconsistent and may be related to the strategy used to achieve high P4 endogenous concentrations in the animal. This review summarizes recent data highlighting the role of progesterone in regulating uterine function and embryo development in cattle
Leishmania major Ribosomal Proteins Extracts Combined with CpG Oligodeoxynucleotides Become Resistant to Disease Caused by a Secondary Parasite Challenge
Get PDFLeishmaniasis is an increasing public health problem and effective vaccines are not currently available. We have previously demonstrated that vaccination with ribosomal proteins extracts administered in combination of CpG oligodeoxynucleotides protects susceptible BALB/c mice against primary Leishmania major infection. Here, we evaluate the long-term immunity to secondary infection conferred by this vaccine. We show that vaccinated and infected BALB/c mice were able to control a secondary Leishmania major challenge, since no inflammation and very low number of parasites were observed in the site of reinfection. In addition, although an increment in the parasite burden was observed in the draining lymph nodes of the primary site of infection we did not detected inflammatory lesions at that site. Resistance against reinfection correlated to a predominant Th1 response against parasite antigens. Thus, cell cultures established from spleens and the draining lymph node of the secondary site of infection produced high levels of parasite specific IFN-γ in the absence of IL-4 and IL-10 cytokine production. In addition, reinfected mice showed a high IgG2a/IgG1 ratio for anti-Leishmania antibodies. Our results suggest that ribosomal vaccine, which prevents pathology in a primary challenge, in combination with parasite persistence might be effective for long term maintenance of immunity
International Review of Social Research 'I am not Spending on my Appearance'! Examining Self-Evaluated Low-Level Consumers of Clothing and Beauty Care in
No full textAbstract: The purpose of this study is to analyse consumers whose identity is not based on appearance-related consumption, but who want distance themselves from consumers willing to spend on physical appearance. The article examines importance of gender, age and place of residence in explaining self-evaluated low-level consumption of beauty care and clothing, and how the proportions of these consumers have changed between socio-demographic groups. The data consists of three cross-sectional consumption and lifestyle surveys collected in 1999 (N = 2 417), 2004 (N = 3 574) and 2009 (N = 1 202). The results suggest that a significant part of Finnish consumers do not consider beauty care or clothing consumption to be a part of their identity. The results indicate some temporal changes in Finnish consumers' beauty care consumption evaluations. It seems that gender differences have been relatively stable, whereas disparities between consumers of different ages as well as urban and rural consumers have diminished
Chapter Title: Accelerating Entrepreneurs and Ecosystems: The Seed Accelerator Model 2 Accelerating Entrepreneurs and Ecosystems: The Seed Accelerator Model
No full textSemantic Visual Analytics for Today's Programming Courses
No full textABSTRACT We designed and studied an innovative semantic visual learning analytics for orchestrating today's programming classes. The visual analytics integrates sources of learning activities by their content semantics. It automatically processs paper-based exams by associating sets of concepts to the exam questions. Results indicated the automatic concept extraction from exams were promising and could be a potential technological solution to address a real world issue. We also discovered that indexing effectiveness was especially prevalent for complex content by covering more comprehensive semantics. Subjective evaluation revealed that the dynamic concept indexing provided teachers with immediate feedback on producing more balanced exams