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B.B. Damian T.C.S. Bonetti D.D.G. Horovitz 《Brazilian journal of medical and biological research》2015,48(1):25-33
Preimplantation genetic diagnosis (PGD) was originally developed to diagnose
embryo-related genetic abnormalities for couples who present a high risk of a
specific inherited disorder. Because this technology involves embryo selection, the
medical, bioethical, and legal implications of the technique have been debated,
particularly when it is used to select features that are not related to serious
diseases. Although several initiatives have attempted to achieve regulatory
harmonization, the diversity of healthcare services available and the presence of
cultural differences have hampered attempts to achieve this goal. Thus, in different
countries, the provision of PGD and regulatory frameworks reflect the perceptions of
scientific groups, legislators, and society regarding this technology. In Brazil,
several texts have been analyzed by the National Congress to regulate the use of
assisted reproduction technologies. Legislative debates, however, are not conclusive,
and limited information has been published on how PGD is specifically regulated. The
country requires the development of new regulatory standards to ensure adequate
access to this technology and to guarantee its safe practice. This study examined
official documents published on PGD regulation in Brazil and demonstrated how little
direct oversight of PGD currently exists. It provides relevant information to
encourage reflection on a particular regulation model in a Brazilian context, and
should serve as part of the basis to enable further reform of the clinical practice
of PGD in the country. 相似文献
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Past research suggests that as many as 50% of onward human immunodeficiency virus (HIV) transmissions occur during acute and recent HIV infection. It is clearly important to develop interventions which focus on this highly infectious stage of HIV infection to prevent further transmission in the risk networks of acutely and recently infected individuals. Project Protect tries to find recently and acutely infected individuals and prevents HIV transmission in their risk networks. Participants are recruited by community health outreach workers at community-based HIV testing sites and drug users' community venues, by coupon referrals and through referrals from AIDS clinics. When a network with acute/recent infection is identified, network members are interviewed about their risky behaviors, network information is collected, and blood is drawn for HIV testing. Participants are also educated and given prevention materials (condoms, syringes, educational materials); HIV-infected participants are referred to AIDS clinics and are assisted with access to care. Community alerts about elevated risk of HIV transmission are distributed within the risk networks of recently infected. Overall, 342 people were recruited to the project and screened for acute/recent HIV infection. Only six index cases of recent infection (2.3% of all people screened) were found through primary screening at voluntary counseling and testing (VCT) sites, but six cases of recent infection were found through contact tracing of these recently infected participants (7% of network members who came to the interview). Combining screening at VCT sites and contact tracing the number of recently infected people we located as compared to VCT screening alone. No adverse events were encountered. These first results provide evidence for the theory behind the intervention, i.e., in the risk networks of recently infected people there are other people with recent HIV infection and they can be successfully located without increasing stigma for project participants. 相似文献
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Katja T. Turunen Vasiliki Pletsa Panagiotis Georgiadis John K. Triantafillidis Dimitrios Karamanolis 《Nutrition and cancer》2016,68(4):560-567
The aim of the study was to determine the effect of β-glucan on the cytotoxicity and genotoxicity of polypectomized patient's fecal water (FW). Polypectomized volunteers (n = 69) were randomly assigned to consume bread with or without β-glucan, for 3 months. FW was collected at the beginning (t = 0), the 30th and 90th day and 2 wk after the intervention. Cytotoxicity and genotoxicity were estimated on Caco-2 cells, using trypan blue exclusion test and comet assay, respectively. Gastrointestinal symptoms were recorded and subjects kept a 3-day food diary at baseline and after completion. Trypan blue exclusion test revealed cell survival of approximately 87% after incubation with FW. The FW samples showed 49% genotoxicity at the baseline. Genotoxicity in the intervention group decreased during the trial reaching statistical significance on the 90th day compared to control. An increase was noticed 2 wk after the trial, but it still remained significantly lower compared to control. Group-specific analysis for β-glucan also revealed significant decrease in the genotoxicity on the 90th day compared to baseline. β-glucan ingestion in polypectomized patients significantly decreased the genotoxicity of their FW. Our findings suggest that β-glucan consumption could possibly provide protection against colon cancer development. 相似文献
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