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BACKGROUND: We present the first powered prospective study to assess whether sperm aneuploidy can predict the outcome of ICSI. METHODS: Our null hypothesis was that aneuploidy rates (AR) are identical in men who achieve successful (Group A) and unsuccessful (Group B) ICSI outcome. A power calculation yielded a sample number of 56 to achieve 80% power to reject our hypothesis at the 5% significance level. Samples for testing were obtained on the day of embryo transfer and tests were performed on raw pre-preparation samples. Sperm AR of chromosomes 13, 18, 21, X/Y were assessed using fluorescence in-situ hybridization (FISH) techniques (mean of 1223 sperm). RESULTS: There was no significant difference in any patient, seminal, cycle or laboratory characteristic between groups that may have affected outcome. Total AR (2.37 versus 1.18%, P = 0.01), as well as AR of chromosomes 18, X/Y and 18 + X/Y (1.48 versus 0.67%, P = 0.005) were significantly higher in Group B compared with Group A. Regression analysis confirmed these differences to be independent of other variables and showed a 2.6-fold change in odds of achieving a pregnancy for every 1% change in total AR. CONCLUSIONS: Our findings confirm a potential role for aneuploidy testing in the work-up of ICSI patients as a predictor of success, as well as in future genetic counselling. If confirmed, there may also be a place for a study of preimplantation genetic screening to improve ICSI success in men found to have high AR and ICSI failure.  相似文献   

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Different methods for recovering epididymal or testicular spermatozoa have been described and each has its drawbacks and advantages. Percutaneous aspiration of the testis may be the method of choice in cases of irreparable obstructive azoospermia. Using a 21-gauge needle, spermatozoa may be recovered in 96 % of patients. More patients undergoing fine-needle aspiration experienced less pain than expected as compared with those undergoing open biopsy. Microsurgical epididymal sperm aspiration (MESA) is the preferred method in patients with an incomplete work-up because, if indicated, a vasoepididymostomy can be performed concomitantly with a full scrotal exploration. In azoospermic patients with testicular failure, the sperm recovery rate, i.e. the chance of finding at least one spermatozoon, is around 50% after multiple open biopsies. However, the fertilization rates after intracytoplasmic sperm injection (ICSI) are significantly lower than in men with normal spermatogenesis, and complete fertilization failure may occur more frequently. Although the combination of testicular sperm extraction (TESE) and ICSI may be the sole treatment available for infertility because of non-obstructive azoospermia, the overall success rate is limited and ongoing pregnancies are obtained in < or =20% of ICSI cycles. In patients with incomplete Sertoli cell-only syndrome, testicular damage may be limited by use of a selective microsurgical approach; less invasive methods such as fine-needle aspiration are not useful in these patients. Of 14 patients with primary testicular failure as proven by histopathology, only in one case (7.1%) were spermatozoa recovered by multiple aspirations, while in nine cases (64.3%) spermatozoa were recovered by open biopsy. Although the pregnancy rates reported after ICSI with frozen-thawed testicular spermatozoa from patients with primary testicular failure are relatively low, the recovery of testicular spermatozoa by open biopsy followed by cryopreservation may be the method of choice by which to prevent repeat surgery and pointless ovarian stimulation in the female partner.  相似文献   

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In two separate prospectively randomized trials, intracytoplasmicsperm injection (ICSI) cycles were studied in a controlled mannerto monitor the effects of either bovine oviductal epithelialcell co-culture (n = 119) or assisted hatching by zona drilling(n = 100). In the first study, immediately following ICSI, alleggs were placed directly either onto partial monolayers ofbovine oviductal cells or into regular culture medium. Althoughthe embryo developmental rate was apparently compromised inpart by the presence of the co-culture cells, ultimately therewere no significant differences in either the viable pregnancyrate (31.6% co-culture versus 29.0% control) or the embryonicimplantation rate (11.4% co-culture versus 13.6% control). Assistedhatching also had no significant impact on ICSI cycle outcomein terms of either the viable pregnancy rate (30.0% assistedhatching versus 32.0% control) or the embryonic implantationrate (8.5% assisted hatching versus 13.5% control). However,in female patients aged 235 years, assisted hatching appearedto convey a marginally significant benefit in terms of boththe viable pregnancy rate (35.5% assisted hatching versus 11.1%control) and the embryonic implantation rate (103% assistedhatching versus 3.1 % control). It seems that the overall improvementof ICSI cycle outcome cannot be achieved by the general applicationof either co-culture or assisted hatching. Nevertheless, itis possible that there remain specific patient groups that mightbenefit from selected use of either of these modalities.  相似文献   

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Neonatal glucose levels correlate negatively with umbilical cord levels of C-peptide, a polypeptide secreted with insulin. In other words, neonatal hypoglycemia results from excessive insulin secretion from fetal/neonatal beta cells. Given that insulin causes fat to be stored rather than to be used for energy, one would expect that chronic hyperinsulinemia would result in large-for-gestational-age neonates. The finding that many small-for-gestational-age neonates have hypoglycemia suggests that the stimulus for insulin production occurs close to delivery. We postulated that a potent stimulation of maternal insulin production close to delivery would also provide a potent stimulus for fetal and neonatal insulin production, causing neonatal hypoglycemia. This study has evaluated 155 mothers with markers of excessive insulin production (such as acanthosis or grade III obesity), or with situations characterized by increased insulin requirements (such as an invasive bacterial infection or use of systemic corticosteroid within a week before delivery; or sedentariness or high-carbohydrate intake within 24 h before delivery) and their 158 neonates who were screened for glycemic levels at 1, 2 and 4 h after birth. The minimum glucose level was correlated to the maternal parameters, and to classical predictors of neonatal hypoglycemia, such as low-birth weight and preterm delivery. The only independent predictors were sedentariness and high-carbohydrate intake within 24 h before delivery. The risk of neonatal hypoglycemia increased five-fold with sedentariness, 11-fold with high-carbohydrate intake, and 329-fold with both risk factors. The risk of neonatal hypoglycemia seems to be highly influenced by maternal lifestyle within 24 h before delivery. Controlled randomized trials may help determine whether a controlled carbohydrate diet combined with regular physical activity close to delivery can prevent neonatal hypoglycemia and all its severe complications to the newborn.  相似文献   

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This study examined developmental timing of brain lesion effects on children's attention skills. The sample of 138 children, 10-16 years at assessment, were grouped based on developmental timing of brain lesion: (1) Congenital; (2) Perinatal; (3) Infancy; (4) Preschool; (5) Middle Childhood; (6) Late Childhood. Children with lesions in infancy or earlier demonstrated global attention problems, while children with lesions in middle childhood performed closer to normal expectations. This pattern of results was particularly evident for encoding and shifting attention. Findings highlight vulnerability of the immature brain to lesions and identify critical periods in development for attention skills.  相似文献   

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Assisted reproductive technology is an evolving area, and several adjuvant procedures have been created to increase a couple''s chance of conceiving. For male infertility, the current challenges are to properly accommodate old and new techniques that are both cost-effective and evidence-based. In this context, urologists are expected to diagnose, counsel, provide medical or surgical treatment whenever possible and/or correctly refer male patients for assisted conception. Urologists are sometimes part of a multiprofessional team in an assisted reproduction unit and are responsible for the above-cited tasks as well as the surgical retrieval of sperm from either the epididymides or testicles. We present a comprehensive review of the surgical treatment options for infertile males, including the perioperative planning and prognostic aspects, with an emphasis on the role of microsurgery in the optimization of treatment results. This review also discusses current techniques for sperm retrieval that are used in association with assisted reproductive technology and includes sperm retrieval success rates according to the technique and the type of azoospermia. New insights are provided with regard to each surgical treatment option in view of the availability of assisted conception to overcome male infertility.  相似文献   

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Current outcome prediction in critically ill patients relies on the art of clinical judgement and/or the science of prognostication using illness severity scores. The biochemical processes underlying critical illness have increasingly been unravelled. Several biochemical markers reflecting the process of inflammation, immune dysfunction, impaired tissue oxygenation and endocrine alterations have been evaluated for their predictive power in small subpopulations of critically ill patients. However, none of these parameters has been validated in large populations of unselected ICU patients as has been done for the illness severity and organ failure scores. A simple biochemical predictor of ICU mortality will probably remain elusive because the processes underlying critical illness are very complex and heterogeneous. Future prognostic models will need to be far more sophisticated.  相似文献   

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In Europe up to one in four couples experience difficulty conceiving and in half of these cases the problem has been attributed to sub or infertility in the male partner. The development of assisted reproductive technologies (ART) such as in vitro fertilization and intra-cytoplasmic spermatozoa injection has allowed some such couples to achieve a pregnancy. Concerns have been raised over the increasing use of ART not least because of the discovery of elevated levels of DNA damage in sperm from subfertile men. The impact of damaged DNA originating in the male germ line is poorly understood, but is thought to contribute to early pregnancy loss (recurrent miscarriage), placental problems and have a long-term impact on the health of the offspring. DNA repair is essential for meiotic recombination and correction of DNA damage in germ cells and proteins involved in all the major repair pathways are expressed in the testis. In this review, we will consider evidence that the production of sperm containing damaged DNA can be the result of suboptimal DNA repair and/or a mild environmental insult, such as heat stress, and how studies in mice may give us insight into the origins and consequences of DNA damage in human sperm.  相似文献   

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Several new TB vaccines are currently undergoing clinical trials. Among the most promising is a vaccine based upon the modified vaccinia virus Ankara-expressing mycobacterial antigen 85A (MVA85A). Given the widespread use of the current TB vaccine, BCG, many of the new TB vaccines are being tested for their ability to boost BCG-induced immunity. The introduction of a new TB vaccine into routine use would be facilitated by its coadministration with other vaccines as a part of the WHO's Expanded Program on Immunization (EPI). In the article under review the authors tested the immunogenicity of MVA85A given alone or in combination with EPI vaccines to infants in The Gambia. Antigen 85A-specific production of IFN-γ by peripheral blood cells was reduced significantly in infants coimmunized with EPI vaccines compared with infants who received the MVA85A vaccine alone. This study highlights a potentially important issue, which should be addressed prior to the introduction of new TB vaccines and, perhaps, other vaccines that require the induction of a so-called Type 1 T-cell-mediated immune response.  相似文献   

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Parasitology Research - Affiliation of Klára J. Petrželková was incorrectly assigned as 2, 9, 10 in the original version of this article when in fact it should have been 3, 9, 10....  相似文献   

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Unlike traditional interventions, Internet interventions allow for objective tracking and examination of the usage of program components. Student Bodies (SB), an online eating disorder (ED) prevention program, significantly reduced ED attitudes/behaviors in college-aged women with high body image concerns, and reduced the development of EDs in some higher risk subgroups. The authors investigated how adherence measures were associated with ED attitudes and behaviors after treatment. Female SB participants (n = 209) completed the Eating Disorders Examination-Questionnaire (EDE-Q; C. G. Fairburn & S. J. Beglin, 1994) at baseline, posttreatment, and 1-year follow-up. Total weeks participation and frequency of utilizing the online Web pages/journals predicted pre- to posttreatment changes in EDE-Q Restraint but not in other ED symptoms. In participants with some compensatory behaviors, discussion board and booster session use were associated with increased weight/shape concerns during follow-up. In overweight participants, higher online Web page/journal use was related to decreased EDE-Q Eating Concern scores during follow-up. This is the first study to investigate the relationship between adherence to specific program components and outcome in a successful Internet-based intervention. Results can be used to inform future development and tailoring of prevention interventions to maximize effectiveness and facilitate dissemination.  相似文献   

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OBJECTIVE: The objective of this study was to demonstrate the association between quality of life and subsyndromal depression in a primary care clinic in a Brazilian sample. METHODS: This was a cross-sectional study. The cases were divided into three groups according to the severity of depressive symptoms: 1) subjects with major depressive disorder; 2) subjects with subsyndromal depression; 3) subjects without depressive symptoms--controls. The participants completed the World Health Organization Instrument to Assess Quality of Life (WHOQOL-BREF), the Quality of Life--Depression (QLDS), the Centers for Epidemiologic Studies--Depression instrument (CES-D), and the Composite International Diagnostic Interview (CIDI). RESULTS: The sample consisted of 438 primary care users (35.2% of them had subsyndromal depression). The subjects with major depression presented the worst impairment of quality of life, which was measured by the WHOQOL-BREF and the QLDS. The patients with subsyndromal depression had a smaller impact on their quality of life and the subjects without depression presented an even lower impact. The hierarchical linear regression involving demographic variables and the severity of depressive symptoms showed that the severity of depression was the variable with higher correlation with quality of life dimensions, presenting increased variation in the domains (from 9% to 24%). CONCLUSIONS: The results suggest that subsyndromal depression causes impairment of the quality of life in primary care patients of a Brazilian sample.  相似文献   

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Objectives and methodsA wealth of online anxiety information exists but much of it is not evidence-based or well-balanced. This study evaluated anxiety websites (N = 20) on readability, quality, usability, visual design, and content.ResultsOverall, websites were of reasonable quality but only half were considered understandable according to the PEMAT usability scale (70% cutoff value). The average reading level across websites was 11.2 (SMOG), which is higher than NIH recommended grade 6–7 level. Websites had variable design features and a trending association suggested websites with better design come up earlier in search results. The number of topics covered varied across websites and most did not adequately cover all topics of interest. Most websites included information about psychological and self-help treatments, how treatment works, and what treatment entails. The Top 5 websites were: (1) Anxiety BC, (2) ADAA, (3) Mind, (4) Beyond Blue, and (5) Web MD.ConclusionsThis is the first study to evaluate existing anxiety information websites based on the dimensions described above and their relationship to Google search results.Practice implicationsThis study highlights the importance of considering several dimensions in developing mental health resources and provides direction for strategies to improve existing websites and/or develop new resources.  相似文献   

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