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Genome Engineering in Vibrio cholerae: A Feasible Approach to Address Biological Issues  [PDF]
Marie-Eve Val,Ole Skovgaard,Magaly Ducos-Galand,Michael J. Bland,Didier Mazel
PLOS Genetics , 2012, DOI: 10.1371/journal.pgen.1002472
Abstract: Although bacteria with multipartite genomes are prevalent, our knowledge of the mechanisms maintaining their genome is very limited, and much remains to be learned about the structural and functional interrelationships of multiple chromosomes. Owing to its bi-chromosomal genome architecture and its importance in public health, Vibrio cholerae, the causative agent of cholera, has become a preferred model to study bacteria with multipartite genomes. However, most in vivo studies in V. cholerae have been hampered by its genome architecture, as it is difficult to give phenotypes to a specific chromosome. This difficulty was surmounted using a unique and powerful strategy based on massive rearrangement of prokaryotic genomes. We developed a site-specific recombination-based engineering tool, which allows targeted, oriented, and reciprocal DNA exchanges. Using this genetic tool, we obtained a panel of V. cholerae mutants with various genome configurations: one with a single chromosome, one with two chromosomes of equal size, and one with both chromosomes controlled by identical origins. We used these synthetic strains to address several biological questions—the specific case of the essentiality of Dam methylation in V. cholerae and the general question concerning bacteria carrying circular chromosomes—by looking at the effect of chromosome size on topological issues. In this article, we show that Dam, RctB, and ParA2/ParB2 are strictly essential for chrII origin maintenance, and we formally demonstrate that the formation of chromosome dimers increases exponentially with chromosome size.
Neoadjuvant endocrine therapy: clinical and biological issues
IE Smith
Breast Cancer Research , 2007, DOI: 10.1186/bcr1702
Abstract: The results of key randomised trials addressing these issues are reviewed.In the P24 trial for patients not suitable for conservative surgery, neoadjuvant letrozole was shown to achieve a significantly greater clinical overall response rate than tamoxifen (56% versus 36%, P < 0.001) and a significantly better incidence of breast-conserving surgery (45% versus 35%, P = 0.02). In the IMPACT trial, neoadjuvant anastrozole was compared with tamoxifen and the combination (three arms, equivalent to adjuvant ATAC). No significant difference in clinical overall response was seen between the three arms although breast-conserving surgery was considered feasibly significantly more often with anastrozole (46%) than with tamoxifen (22%) or with the combination (26%) (P = 0.03). In the PROACT trial, neoadjuvant anastrozole achieved a higher clinical overall response rate than tamoxifen (50% versus 40%) but this difference was not significant (in the endocrine therapy alone group – excluding patients also treated with chemotherapy). Breast-conserving surgery was achieved significantly more often with anastrozole (43% versus 31%, P = 0.04).The optimum duration of neoadjuvant endocrine therapy prior to surgery has not been established but circumstantial evidence suggests that it is at least 4 months, and probably longer.In the P24 trial and the IMPACT trial, patients with higher levels of ER expression had a significantly higher chance of clinical response. Likewise in both trials, aromatase inhibitors appeared strikingly more effective than tamoxifen in the subgroup of patients with HER2-positive, ER-positive tumours.In the IMPACT trial, the change in proliferation rates after 2 weeks of treatment as measured by Ki67 was significantly greater for anastrozole than for tamoxifen or the combination, reflecting results in the adjuvant ATAC trial, and suggesting that Ki67 might be a better marker for long-term outcome than clinical response. Likewise, long-term follow-up of the IMPACT t
Some Critical Issues of Women Entrepreneurship in Rural India  [PDF]
VIJAY KUMBHAR
European Academic Research , 2013,
Abstract: The aim of this study is to discuss the issues regarding women entrepreneurship in rural India. This paper is mostly based on secondary data and some observations; for the identification of these issues the author has reviewed different research articles and reports. Findings of this study reveal that absence of definite agenda of life, absence of balance between family and career obligations of women, poor degree of financial freedom for women, absence of direct ownership of the property, the paradox of entrepreneurial skill & finance in economically rich and poor women, no awareness about capacities, low ability to bear risk, problems of work with male workers, negligence by financial institutions, lack of self-confidence, lack of professional education, mobility constraints and lack of interaction with successful entrepreneurs are major problems of women entrepreneurship development in India.
Head Teachers, Women and Hesitation to Discuss Gender Issues  [PDF]
Maria Hedlin
Open Journal of Social Sciences (JSS) , 2017, DOI: 10.4236/jss.2017.56021
Abstract: The purpose of this paper is to explore how a group of Swedish head teachers approaches the importance of gender issues in terms of their work. The empirical material is from so-called research circles, which were part of a gender equality project conducted in southern Sweden. A research circle is similar to a focus group interview. The group, which consists of eight women who were head teachers within compulsory education, met on six occasions. The results show that the women initially expressed strong hesitation about whether discussing gender issues in relation to the role of head teacher was beneficial at all. The entire gender equality project was called into question by the suggestion that the connection between head teacher and gender implied a weakening of women. However, examples of gender playing a role within educational settings were increasingly noted. By highlighting female head teachers ambivalence towards discussing issues related to gender and gender equality, this paper contributes to the discussion about why these issues do not occupy a stronger position within schools. Also, the female head teachers hesitation and ambivalence are connected to the decline in status of the head teacher profession due to the restructuring of education, for which women in educational leadership in Sweden have been blamed.
Violence against Women: Methodological and Ethical Issues  [PDF]
Kaltrina Kelmendi
Psychology (PSYCH) , 2013, DOI: 10.4236/psych.2013.47080
Abstract:

Research on violence against women has improved and provides important information on patterns, prevalence, risk and consequences of this major threat to female well-being. Since the identification of violence against women as a problem worthy of study in 1970, evident progress has been made in understanding physical, psychological and sexual violence against women. However, while methodological improvements appear in later studies, the literature review shows many limitations and restrictions when conducting research on violence against women. The objective of this paper is to review the methodological issues that arise when studying violence against women. The paper focuses first on the history of research on violence against women, by elaborating on each perspective. Second, the paper identifies and describes methodological difficulties when researching violence against women such as methodology, operational definitions of violence, sampling frame and risk factors related to violence. The paper also elaborates on major ethical principles that should be considered and respected when researching violence against women. Finally, the paper recommends certain changes that should be made in order to improve future research on the subject.

Physical Schemata Underlying Biological Pattern Formation - Examples, Issues and Strategies  [PDF]
Herbert Levine,Eshel Ben-Jacob
Quantitative Biology , 2004, DOI: 10.1088/1478-3967/1/2/P01
Abstract: Biological systems excel at building spatial structures on scales ranging from nanometers to kilometers and exhibit temporal patterning from milliseconds to years. One approach that nature has taken to accomplish this relies on the harnessing of pattern-forming processes of non-equilibrium physics and chemistry. For these systems, the study of biological pattern formation starts with placing a biological phenomenon of interest within the context of the proper pattern-formation schema and then focusing on the ways in which control is exerted to adapt the pattern to the needs of the organism. This approach is illustrated by several examples, notably bacterial colonies (diffusive-growth schema) and intracellular calcium waves (excitable-media schema).
Looking good and judging gazes: The relationship between body ideals, body satisfaction and body practices among Norwegian men and women  [PDF]
Mari Rysst, Ingun Grimstad Klepp
Health (Health) , 2012, DOI: 10.4236/health.2012.45042
Abstract: This article compares how people with normal bodies and bodies that deviate from dominant media-depicted body ideals, live with and accept their bodies. Media images of ideal bodies encompass judging gazes. These gazes affect and discipline people and may make it challenging for them to accept their bodies. The data material is part of the interdisciplinary Nordic project called “Beauty comes from within: looking good as a challenge in health promotion”. Based on 20 interviews with Norwegian men and women, of whom 10 have particular appearance-related problems, the article discusses the relationship between the media-depicted body ideals, descriptions by informants of what a good-looking body is, body satisfaction and body practices. The article shows resonance between how people describe good-looking bodies and satisfaction or not with own bodies. Women express more dissatisfaction with their bodies than men, but the article shows that many have strategies for trying to accept their bodies as they are. The comparative perspective highlight that the people having deviant bodies, more than those with normal bodies, balance the idea of “being myself” with the idea of “doing the best out of my (bodily) situation”. Most interestingly, they show that it is harder to accept handicaps that are changeable, like overweight, than harelips, deformed legs and skin injuries. As such, overweight becomes a double burden.
Gynaecological and Reproductive Health Issues in HIV-Positive Women
CO Agboghoroma
West African Journal of Medicine , 2010,
Abstract: BACKGROUND: Women constitute over 60 percent of the HIVinfected population in sub-saharan Africa. Highly active antiretroviral therapy (HAART) has improved the life span of people living with human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS). Advances in scientific knowledge and management of the HIV-positive pregnant woman have also led to reduction in the risk of motherto- child transmission (MTCT) of HIV. The gynaecological and reproductive health needs and care of the HIV-positive woman are poorly appreciated, suboptimal and largely neglected, with potential to negatively affect their quality of life and efforts at control of the HIV epidemic. OBJECTIVE: To review the contemporary gynaecological and reproductive health problems and management of the HIVpositive woman. METHODS: A review of local and international publications on gynaecology / reproductive health and HIV from indexed / online journals and relevant websites using Pubmed and Google search in the period between 1980 and March 2009. RESULTS: The HIV-positive woman suffers increased frequency and severity of pelvic infections and cervical premalignant and malignant lesions. Relapses and treatment failures of these conditions are common among these patients. Infertility and contraception are also challenges to the HIVpositive woman. Gynaecological and reproductive health care is an integral part of the comprehensive health care needs of the HIV-positive woman. CONCLUSION: In addition to antiretroviral treatment, HIVpositive women should be provided regular screening for sexually transmitted infections (STIs), cervical cytology, counselling and services for infertility and contraception. Appropriate attention to the gynaecological and reproductive health needs of the HIV-positive woman will improve her general health status and quality of life and contribute to reduction in the incidence of HIV infection.
Adverse biological effects of Milan urban PM looking for suitable molecular markers of exposure  [PDF]
Mantecca Paride,Gualtieri Maurizio,Longhin Eleonora,Bestetti Giuseppina
Chemical Industry and Chemical Engineering Quarterly , 2012, DOI: 10.2298/ciceq120206114m
Abstract: The results presented summarise the ones obtained in the coordinated research project Tosca, which extensively analysed the impact of Milan urban PM on human health. The molecular markers of exposure and effects of seasonally and size-fractionated PMs (summer and winter PM10, PM2.5) were investigated in in vitro (human lung cell lines) and in vivo (mice) systems. The results obtained by the analyses of cytotoxic, pro-inflammatory and genotoxic parameters demonstrate that the biological responses are strongly dependent upon the PM samples seasonal and dimensional variability, that ultimately reflect their chemical composition and source. In fact summer PM10, enriched in crustal elements and endotoxins, was the most cytotoxic and pro-inflammatory fraction, while fine winter PMs induced genotoxic effects and xenobiotic metabolizing enzymes (like CYP1B1) production, likely as a consequence of the higher content in combustion derived particles reach in PAHs and heavy toxic metals. These outcomes outline the need of a detailed knowledge of the PMs physico-chemical composition on a local scale, coupled with the biological hazard directly associated to PM exposure. Apparently this is the only way allowing scientists and police-makers to establish the proper relationships between the respirable PM quantity/quality and the health outcomes described by clinicians and epidemiologists.
Inference of complex biological networks: distinguishability issues and optimization-based solutions
Gábor Szederkényi, Julio R Banga, Antonio A Alonso
BMC Systems Biology , 2011, DOI: 10.1186/1752-0509-5-177
Abstract: We claim that another major difficulty for solving these inference problems is the frequent lack of uniqueness of many of these networks, especially when prior assumptions have not been taken properly into account. Our contributions aid the distinguishability analysis of chemical reaction network (CRN) models with mass action dynamics. The novel methods are based on linear programming (LP), therefore they allow the efficient analysis of CRNs containing several hundred complexes and reactions. Using these new tools and also previously published ones to obtain the network structure of biological systems from the literature, we find that, often, a unique topology cannot be determined, even if the structure of the corresponding mathematical model is assumed to be known and all dynamical variables are measurable. In other words, certain mechanisms may remain undetected (or they are falsely detected) while the inferred model is fully consistent with the measured data. It is also shown that sparsity enforcing approaches for determining 'true' reaction structures are generally not enough without additional prior information.The inference of biological networks can be an extremely challenging problem even in the utopian case of perfect experimental information. Unfortunately, the practical situation is often more complex than that, since the measurements are typically incomplete, noisy and sometimes dynamically not rich enough, introducing further obstacles to the structure/parameter estimation process. In this paper, we show how the structural uniqueness and identifiability of the models can be guaranteed by carefully adding extra constraints, and that these important properties can be checked through appropriate computation methods.During the last decade, the wide availability of high-throughput biological data has made it possible to produce new knowledge via a systems biology approach [1-3]. The inference of biochemical networks (i.e. the mathematical mapping of the mole
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