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101.
The question of payment to egg donors has recently focused the attention of both the Human Fertilisation and Embryology Authority (HFEA) and licensed clinics. An acute shortage of egg donors and the rising costs of assisted conception treatment are matters of grave concern to many patients. To understand the emotional and social effects of egg sharing and egg donation, we conducted a survey of attitudes in a group of women who had some knowledge or experience of egg donation. A total of 750 questionnaires were sent out of which 217 were returned within the specified time limit. From these, 107 respondents had experience of egg donation and 110 had made enquiries about donation. The data from these questionnaires were collated and tabulated by the National Opinion Polls (NOP) Research Group. An analysis of the data produced the following key findings: (i) donating or sharing eggs is a social issue, 94% discuss it with partners/family/friends; (ii) altruistic motives are not the prerogative of non-patient volunteers-egg share donors felt that helping the childless was as important as having a chance of in-vitro fertilization (IVF) for themselves; (iii) the treatment procedure causes the most anxiety for egg donors. The recipients were most concerned about delays, donor characteristics and how the eggs were allocated; (iv) most respondents (65%) with prior experience of egg sharing would do it again - 63% of egg share donors, 72% of egg share recipients; (v) cash rewards to egg donors and outright advertising for donors were rejected by 64 and 62% of the sample respectively; and (vi) counselling was highly valued and there were no instances of 'shattered lives' after treatment. The findings do not support the recently announced intentions of the HFEA to disallow payment to gamete donors on the grounds of devalued consent. There is no precedent in modern medicine for egg sharing. The patients surveyed drew a clear distinction between egg sharing and financial rewards. As long as egg donation is not covered by the National Health Service, it is fairer to offer egg sharing than to refuse treatment to those unable to pay.   相似文献   
102.
In the post-Human Genome Project era, the debate on the concept of race/ethnicity and its implications for biomedical research are dependent on two critical issues: whether and how to classify individuals and whether biological factors play a role in health disparities. The advent of reliable estimates of genetic (or biogeographic) ancestry has provided this debate with a quantitative and more objective tool. The estimation of genetic ancestry allows investigators to control for population stratification in association studies and helps to detect biological causation behind population-specific differences in disease and drug response. New techniques such as admixture mapping can specifically detect population-specific risk alleles for a disease in admixed populations. However, researchers have to be mindful of the correlation between genetic ancestry and socioeconomic and environmental factors that could underlie these differences. More importantly, researchers must avoid the stigmatization of individuals based on perceived or real genetic risks. The latter point will become increasingly sensitive as several 'for profit companies' are offering ancestry and genetic testing directly to consumers and the consequences of the spread of the services of these companies are still unforeseeable.  相似文献   
103.
Mitotane is often considered the front-line hormonal therapyof adrenocortical carcinoma (ACC). An illustrative case concerningthis issue and the rationale to ponder other alternatives isreported. A 69 year-old woman, diagnosed with ACC was admittedwith hypertensive crisis, supraventricular tachycardia, congestiveheart-failure, diarrhoea and rabdomyolisis. Two years earlier,she had undergone  相似文献   
104.
105.
Bacterial vaginosis (BV) is considered as a trigger for an inflammatory response that could promote adverse pregnancy outcome (APO). We hypothesized that BV-related inflammation could be counterbalanced by anti-inflammatory and mucosal homeostatic responses that could participate in pregnancy outcomes.A total of 402 vaginal self-samples from pregnant women in their first trimester were screened by Nugent score. In this population, we enrolled 23 pregnant women with BV but without APO, 5 pregnant women with BV and developing APO, 21 pregnant women with intermediate flora, and 28 random control samples from pregnant women without BV or APO.BV without APO in pregnant women was associated with 28-fold interleukin-8, 5-fold interleukin-10, and 40-fold interleukin-22 increases in expression compared to controls. BV associated with APO in pregnant women shared 4-fold increase in tumor necrosis factor, 100-fold decrease in interleukin-10, and no variation in interleukin-22 expressions compared to controls. Next-generation sequencing of vaginal microbiota revealed a shift from obligate anaerobic bacteria dominance in BV without APO pregnant women to Lactobacillus dominance microbiota in BV with APO.Our results show that the anti-inflammatory and mucosal homeostatic responses to BV may determine outcome of pregnancy in the setting of BV possibly through effects on the vaginal microbiota.  相似文献   
106.
107.
AIM: To investigate the prognostic role of genomic stability and copy number alterations (CNAs) pancreatic neuroendocrine tumors (PanNETs).METHODS: A high-resolution array-based comparative genomic hybridization approach was utilized in order to investigate and quantify chromosomal aberrations in a panel of 37 primary PanNET and 11 metastatic samples. DNA samples were extracted from formalin-fixed and paraffin-embedded tumor specimen. Genomic findings were correlated with histopathological and immunohistochemical data. Moreover, the dataset was subjected to employing an unsupervised hierarchical clustering analysis approach utilizing Euclidean distance and average linkage and associations between genomically defined tumor groups and recurrent CNAs or clinicopathological features of the study group were assessed.RESULTS: Numerous chromosomal aberrations were recurrently detected in both, primary tumor samples and metastases. Copy number gains were most frequently observed at 06p22.2-p22.1 (27.1%), 17p13.1 (20.8%), 07p21.3-p21.2 (18.8%), 09q34.11 (18.8%). Genomic losses were significantly less frequent and the only recurrent aberration affected 08q24.3 (6.3%). Moreover, we detected a high degree of genomic heterogeneity between primary tumors and metastatic lesions. Unsupervised hierarchical clustering of loci affected by CNAs in more than 3 primary tumor samples revealed two genetically distinct tumor groups as well as two chromosomal clusters of genomic imbalances indicating a small subset of tumors with common molecular features (13.5%). Aberrations affecting 6p22.2-22.1, 8q24.3, 9q34.11 and 17p13.1 (P = 0.011; 0.003; 0.003; 0.001), were significantly associated with a poorer survival prognosis.CONCLUSION: This study suggests that several frequent CNAs in numerous candidate regions are involved in the pathogenesis and metastatic progression of PanNET.  相似文献   
108.
Initial studies have shown that recombinant human interleukin-6 (rhIL- 6) induces anemia. Until now, the pathophysiologic mechanism of this induced anemia has been unknown. To unravel the underlying mechanism, we examined 15 cancer patients receiving rhIL-6 as an antitumor immunotherapy in a phase II study. rhIL-6 was administered subcutaneously at 150 micrograms once daily for 6 consecutive weeks. Various hematologic and biochemical parameters were measured weekly during rhIL-6 treatment and 4 weeks after rhIL-6 discontinuation. To determine plasma volume and red blood cell (RBC) volume, radioisotope dilution assays with labeled autologous RBCs and with human serum albumin were performed before rhIL-6 administration and on day 8 of rhIL-6 therapy. Hemoglobin levels decreased (mean change +/- SE) 7% +/- 1.5% within 3 days after the start of rhIL-6 therapy (P < .0001) and 19% +/- 2% at week 4. Levels had normalized at follow-up. The plasma volume increased 18% +/- 5% during the first week of rhIL-6 administration (P < .003), whereas RBC volume remained unaffected. The mean RBC corpuscular volume remained unchanged for 2 weeks and then began to decrease slowly, reaching its nadir at week 6 (5% +/- 1%; P < .01). Serum iron levels decreased 65% +/- 12% at week 4 (P < .002) and then returned to initial baseline values. Erythropoietin levels increased rapidly up to 68% at week 3 (P < .0001) and had normalized 4 weeks after rhIL-6 therapy. Levels of serum albumin, prealbumin, and transferrin decreased (P < .0001, P < .003, and P < .0001, respectively), whereas levels of serum amyloid A (P < .003), C-reactive protein, haptoglobin, and alpha-1-antitrypsin (P < .0001) increased during rhIL-6 treatment. All levels returned to pretreatment values after discontinuation of rhIL-6. No alterations in reticulocyte counts, serum lactic dehydrogenase levels, and bilirubin levels were observed. A 6-week regimen of subcutaneous rhIL-6 results in a rapid dilution anemia, caused by an acute and significant increase in plasma volume and followed by hypoferremia. This anemia is reversible after the cessation of rhIL-6 treatment.  相似文献   
109.
BACKGROUND/AIMS: Interferon alpha (IFN-alpha) therapy for chronic hepatitis C may trigger induction of autoimmunity against several organs. Immune reactions against distinct adrenocortical protein antigens involved in adrenal autoimmune disease have not been reported to date. Therefore, we investigated the development of highly sensitive and specific adrenal autoantibodies in patients with chronic hepatitis C in response to IFN-alpha treatment. In addition, we studied induction of pancreatic islet and thyroid autoantibodies. PATIENTS/METHODS: Sera of 75 patients (42 males, 33 females; mean age 47 (13) years) were analysed before, during, and after IFN-alpha therapy (9-18x10(6) IE/week; mean duration 8.3 (3.5) months). Autoantibodies (Abs) to adrenal 21-hydroxylase (21OH-Abs), and to islet glutamic acid decarboxylase (GAD65-Abs) and protein tyrosine phosphatase (IA2-Abs) were determined by a radiobinding assay using (35)S labelled protein generated by an in vitro translation system. Thyroid antibodies were measured by a commercially available ELISA. RESULTS: Thirteen of 75 patients were initially positive for some of the autoantibodies. During or after IFN-alpha therapy, 3/62 initially negative patients (4.8%) developed 21OH-Abs. GAD65-Abs or IA2-Abs appeared in 5/62 and 1/62 patients, respectively (9.7% in total). In 12/62 patients (19.4%), thyroid specific antibodies appeared. In none of the 21OH-Ab positive subjects was adrenal dysfunction observed, and no patient with islet autoantibodies developed diabetes mellitus or impaired glucose tolerance. CONCLUSIONS: IFN-alpha induces 21OH-Abs in some cases, while islet and thyroid specific autoantibodies are more frequently found. However, our results indicate for the first time that the adrenal cortex also has to be considered as a potential target of IFN-alpha related autoimmunity.  相似文献   
110.
Church  WR; Bhushan  FH; Mann  KG; Bovill  EG 《Blood》1989,74(7):2418-2425
Vitamin K deficiency or administration of vitamin K antagonists results in the biosynthesis of abnormal des-gamma-carboxy forms of the vitamin K-dependent proteins. Monoclonal antibody H-11 binds several vitamin K- dependent proteins at a determinant that includes the first two residues of gamma-carboxyglutamic acid. Antibody H-11 binds fully carboxylated prothrombin and protein C in the presence of EDTA but binding is inhibited by the divalent metal ions, calcium, magnesium, and manganese. By contrast, des-gamma-carboxy prothrombin and protein C bind antibody H-11 the same in the presence of EDTA or calcium ion. Antibody H-11 thus appears to bind a conserved antigenic site containing gamma-carboxyglutamic acid that in the presence of divalent metal ion undergoes a conformational transition. This ability of antibody H-11 to bind des-gamma-carboxy prothrombin and protein C in the presence of calcium ion allowed the development of an immunoassay for these proteins in plasma. Prothrombin and protein C from stably anticoagulated individuals receiving warfarin were characterized by their ability to bind antibody H-11 in the presence of calcium ion. Binding of prothrombin and protein C to antibody H-11 in the presence of calcium correlated temporally with warfarin administration. The inability of calcium ion to inhibit binding of antibody H-11 to abnormal prothrombin and protein C in plasma suggests that the circulating forms of both proteins following warfarin administration cannot undergo the metal ion-dependent conformational transition that includes sequence residues 1 through 12.  相似文献   
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