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Journal of Assisted Reproduction and Genetics - Extracellular vesicles (EVs) secreted by the epididymal epithelium transfer key factors to maturing spermatozoa. Using an in vitro system previously...  相似文献   
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Suppression and subsequent rebound of ovarian activity using a progestin (levonorgestrel; Norplant) versus a GnRH antagonist (antide) was assessed in the domestic cat via fecal estradiol and progesterone metabolite analyses. Following an initial dose-response trial, queens were assigned to one of four treatments: (1) antide, two 6 mg/kg injections 15 days apart (n = 8 cats); (2) levonorgestrel, six silastic rods (36 mg levonorgestrel/rod) implanted for 30 days (n = 8); (3) control injections (n = 5); and (4) control implants (n = 5). Steroid metabolites were quantified from daily fecal samples for 90 days before, 30 days during, and 90 days after treatment. Antide and levonorgestrel inhibited estrous cyclicity in contrast to continued cyclicity in controls. Cats already at estradiol baseline in antide (n = 7) and levonorgestrel (n = 4) groups remained inhibited during treatment. In females with elevated estradiol levels at treatment onset (Day 0), a normal estradiol surge was completed before concentrations declined to baseline (∼Days 5-7) and remained suppressed throughout the remaining treatment period. Additionally, 56% of treatment animals exhibited at least one spontaneous ovulation during the pre-treatment period, but no female ovulated during treatment with levonorgestrel or antide. Antide-treated cats exhibited lower (P < 0.05) baseline estradiol concentrations during treatment compared to pre- and post-treatment. In contrast, levonorgestrel induced elevations in baseline estradiol following treatment compared to pre- and during treatment intervals. Control females showed no change (P > 0.05) in baseline estradiol throughout the study period. All levonorgestrel and antide cats returned to estrus after treatment withdrawal. Results demonstrate that: (1) both antide and levonorgestrel are effective for inducing short-term suppression of follicular recruitment and ovulation in the cat; (2) inhibition is reversible; and (3) GnRH antagonists and progestins differentially regulate basal estradiol secretion. This study also confirmed a relatively high incidence of spontaneous ovulation in the cat, a species generally considered to be an induced ovulator.  相似文献   
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Human herpesvirus type 8, or Kaposi's sarcoma-associated herpesvirus (KSHV), is the only known human g(2) herpesvirus (rhadinovirus) and the most recently discovered tumor virus. KSHV is associated with Kaposi's sarcoma and two other lymphoproliferative disorders in the AIDS setting: primary effusion lymphoma and the plasma cell variant of multicentric Castleman's disease. This review offers an update on the epidemiology and the role of KSHV genes in the development of disease.  相似文献   
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Outcomes after peripheral blood stem cell transplantation (PBSCT) for chronic phase chronic myeloid leukemia (n = 37) were compared with outcomes after bone marrow transplantation (BMT) (n = 54) in the HLA-compatible unrelated donor setting. Median follow-up was 17 months after PBSCT and 29 months after BMT. Both neutrophil and platelet recovery were faster after PBSCT (P <.05). PBSCT was associated with improved immune reconstitution, with higher peripheral blood naive (CD4(+)CD45RA(+)) and memory (CD4(+) CD45RO(+)) helper T cells at 3 months and 12 months after transplantation (P <.03). The cumulative incidence of acute (grades II-IV) and chronic graft-versus-host disease (GVHD) were similar, but BMT was associated with a higher cumulative incidence of severe, acute (grade III-IV) GVHD at 24% as compared with 8% with PBSCT (P <.05). Molecular relapse, defined by 2 consecutive positive polymerase chain reaction assays for bcr-abl within a 4-week interval, occurred in 12 of 45 evaluable patients (27%) after BMT and in 4 of 37 (11%) after PBSCT (not significant). Cytogenetic relapse occurred in 5 of 54 patients after BMT (9%) and in 1 of the 37 (3%) patients after PBSCT (not significant). Seventeen of the 54 patients died after BMT (31%), as compared with 2 of 37 patients after PBSCT (5%). Deaths in the BMT group were associated mainly with infections and severe, acute GVHD. The estimated probability of transplant-related mortality (TRM) and disease-free survival at 1000 days after receiving the transplant were 30% and 64% in the BMT group and 5% and 91% in the PBSCT group (P <.03). Overall survival 1000 days after receiving the transplant was 66% after BMT and 94% after PBSCT (P <.02). In the multivariate analysis, only acute GVHD significantly influenced TRM (P <.01).  相似文献   
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BACKGROUND: Monitoring of circulating tumor cells (CTCs) in blood of carcinoma patients treated with novel compounds may be a measurement of treatment effectiveness. Before it can be used clinically, a reliably method is needed to enumerate CTCs. We compared two methods for CTC enumeration, OnkoQuick and the CellSearch system. METHODS: We drew 22.5 ml of blood into three CellSave tubes from 15 healthy donors and 61 patients with metastatic carcinoma. After pooling, 15 ml was processed with OncoQuick and 7.5 ml with CellSearch. RESULTS: With both methods no CTCs were found in healthy donors. At least one CTC was detected in 14 of 61 patients (23%) with OncoQuick and 33 of 61 patients (54%) with CellSearch (P < 0.0001). The number of CTCs detected was larger for CellSearch (mean 20 CTCs/7.5 ml of blood) than for OncoQuick (3 CTCs/7.5 ml; P < 0.0001). CONCLUSION: The CellSearch system is a more accurate and sensitive method to enumerate CTCs. Further studies are warranted to evaluate CTC enumeration by the CellSearch system as a monitoring tool for the evaluation of the efficacy of novel anticancer agents.  相似文献   
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The polymorphic gene expression of CYP2C19 causes individual variability in drug metabolism and thereby in pharmacologic and toxicologic responses. We genotyped 286 patients and their donors for the CYP2C19 gene who underwent allogeneic transplantation for various diseases and analyzed their outcome. Patients were classified as: poor metabolizers (PMs; 3.1%), intermediate metabolizers (IMs; 24.5%) and extensive metabolizers (EMs; 72.5%). Patients genotyped as PMs had significant higher hepato- and nephrotoxicities compared to IMs or EMs. Maximum bilirubin and serum creatinine levels measured after transplant were approximately twofold higher than those of EMs or IMs. The increased toxicity resulted in an increased 4-year estimate for transplant-related mortality (TRM) with 50+/-18.6% for PMs compared to 25.1+/-3.7% for EMs (P<0.018) and 22.7 +/-5.6% for IMs (P<0.042), whereas no significant influence for relapse rate, overall survival or incidence of acute graft-versus-host disease grade 2-4 were found between the groups. Multivariate analysis including all potential factors that might influence TRM confirmed that the genotype of CYP2C19 is an independent factor, which influenced TRM significantly. These results suggest that genotyping for CYP450 2C19 can help to identify patients with higher risk for TRM.  相似文献   
39.
Diabetes mellitus has been reported to be associated with an increased risk for colorectal cancer. The review analyzes current epidemiological data on the association of diabetes and the risk for colorectal cancer. Hyperinsulinemia, hyperglycemia, and inflammation are suggested to play a key role in the pathophysiology of cancer in diabetes. Data regarding potential treatment-related risks, particularly in conjunction with the use of insulin and insulin analogues, are also presented. Furthermore, the impact of glycemic control and cardiorespiratory fitness on cancer prognosis is considered. Finally, the preventive potential of aspirin and other nonsteroidal anti-inflammatory drugs, and the recommendations concerning colonoscopy-screening are presented.  相似文献   
40.
Atypical chronic myeloid leukemia (aCML) occurs rarely and is associated with a poor prognosis when treated with conventional chemotherapy. We evaluated the outcome of aCML after allogeneic hematopoietic stem cell transplantation (HSCT). Nine patients were transplanted from HLA-identical siblings (n = 4), HLA-compatible unrelated donors (n = 4) or twin brother (n = 1). Median follow-up was 55 months after transplant (range, 9.1-118.1 months). One patient who was transplanted in advanced disease with bone marrow from his twin brother relapsed 19 months post transplant. This patient was successfully retransplanted from the original donor. All patients remained in complete remission. Analysis of the leukocyte chimerism of peripheral white blood cells and bone marrow buffy coat cells by VNTR-polymerase chain reaction (PCR) and single-nucleotide polymorphism real-time PCR revealed complete chimerism in all patients who had received an allogeneic transplant. One patient suffering from cerebral toxoplasmosis died 9 months post transplant. All other patients were alive at the time of analysis. Our findings suggest that the outcome of allogeneic or syngeneic transplantation in patients with aCML may not be worse than the outcome of transplantation for BCR-ABL-positive CML.  相似文献   
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