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In-vitro fertilization patients (n = 15) at risk of ovarian hyperstimulation syndrome (OHSS) (oestradiol > or =4500 pg/ml on the day of human chorionic gonadotrophin administration and 25 or more follicles of intermediate or large size) underwent aspiration of all follicles and cryopreservation of all fertilized oocytes at the pronuclear stage. Patients were monitored for up to 2 weeks post- retrieval. Subsequent transfer of cryopreserved-thawed embryos was performed in programmed cycles using exogenous oestrogen and progesterone for endometrial preparation. Two patients (13%) developed OHSS necessitating hospitalization and vaginal aspiration of ascitic fluid. Two other patients (13%) developed moderate OHSS requiring ascitic fluid vaginal aspiration in the office setting, with dramatic improvement of the condition. Subsequent transfer of cryopreserved- thawed embryos yielded a clinical pregnancy rate of 58% per transfer and ongoing or delivery rates of 42 and 67% per transfer and per patient respectively. By eliminating pregnancy potential with cryopreservation of all prezygotes and examining the pregnancy potential with subsequent cryopreserved-thawed transfers, it is concluded that OHSS is reduced, but not eliminated for patients at risk. Subsequent transfer of cryopreserved-thawed prezygotes in a programmed cycle with exogenous steroids yields an excellent pregnancy rate.   相似文献   
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Mutations in the gene encoding the isocitrate dehydrogenase 1 gene (IDH1) occur at a high frequency (up to 80%) in many different subtypes of glioma. In this study, we have screened for IDH1 mutations in a cohort of 496 gliomas. IDH1 mutations were most frequently observed in low grade gliomas with c.395G>A (p.R132H) representing >90% of all IDH1 mutations. Interestingly, non‐p.R132H mutations segregate in distinct histological and molecular subtypes of glioma. Histologically, they occur sporadically in classic oligodendrogliomas and at significantly higher frequency in other grade II and III gliomas. Genetically, non‐p.R132H mutations occur in tumors with TP53 mutation, are virtually absent in tumors with loss of heterozygosity on 1p and 19q and accumulate in distinct (gene‐expression profiling based) intrinsic molecular subtypes. The IDH1 mutation type does not affect patient survival. Our results were validated on an independent sample cohort, indicating that the IDH1 mutation spectrum may aid glioma subtype classification. Functional differences between p.R132H and non‐p.R132H mutated IDH1 may explain the segregation in distinct glioma subtypes. © 2010 Wiley‐Liss, Inc.  相似文献   
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To elucidate the molecular mechanisms of spinal fusion with different graft materials during an anterior lumbar interbody fusion, we examined the gene-expression profiles after implantation of equine bone protein extract, rhBMP-2 and autograft using microarray technology and data analysis, including hierarchical clustering, self-organizing maps (SOM), KEGG pathway and Biological process GO analyses in a porcine model. The results suggest that equine bone protein extract exhibited a more similar expression pattern with autograft than that of rhBMP-2. rhBMP-2 recruits progenitor cells, proliferation and differentiation possibly by inducing various factors including PGHS-2, IFGBP-2, VEGF and chemokines and then leads to preferable membranous ossification and bone remodeling. Conversely, equine bone protein extract results in endochondral ossification via upregulation of cartilage-related genes. Ossification by inducing direct osteoblastic differentiation and obviating the cartilaginous intermediate phases may increase spinal fusion rate.  相似文献   
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IntroductionThe free radial forearm (FRFA) flap is universally still considered as the gold standard technique in penile reconstruction. Typically, a considerably large flap is required, often involving almost the entire circumference of the forearm. Partial necrosis may occur at the distal-most (dorsoradial) part of the flap as a result of insufficient perfusion.AimTo describe a new technique using the posterior interosseous artery (PIOA) to supercharge FRFA phalloplasty.MethodsIn a 12-month period, all patients having FRFA flap phalloplasty were enrolled. Perioperative, after complete flap dissection, an indocyanine green perfusion scan was performed. In case of insufficient perfusion at the distalmost part of the flap, a supramicrosurgical anastomosis was performed between the FRFA pedicle and the PIOA (artery only).Main Outcome MeasuresStudied outcomes included the rate of marginal necrosis, surgical time, postoperative posterior interosseous nerve damage and urethral complications (fistula, stenosis or necrosis).ResultsA total of 27 FRFA flap phalloplasties was performed. Anastomosis of the PIOA was needed in 15 cases. No marginal necrosis was observed in these cases. There were no cases of postoperative posterior interosseous nerve damage. There were no significant differences in urethral complications (fistula, stenosis or necrosis) between the 2 groups.Clinical ImplicationsIn selected cases where insufficient perfusion of the dorsoradial part of the flap is present, patients may benefit from arterial supercharging to prevent postoperative marginal necrosis.Strength & LimitationsStrengths include a single surgeon, thus lending continuity of skill and technique, a consecutive series, and 100% short-term follow-up. Limitations include single institution series and a limited number of patients.ConclusionArterial supercharging is effective in improving perfusion of large FRFA flaps used in phalloplasty when dorsoradial hypoperfusion is detected on an indocyanine green perfusion scan. It is a technically challenging addition to the standard technique because of the small size of the vessels, the close relationship between the PIOA and the posterior interosseous nerve, and the vulnerability of the newly constructed intra-flap anastomosis.De Wolf E, Claes K, Sommeling CE, et al. Free Bipedicled Radial Forearm and Posterior Interosseous Artery Perforator Flap Phalloplasty. J Sex Med 2019;16:1111–1117.  相似文献   
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BACKGROUND: The initial rate of plasma HIV-1 RNA (pVL) decline has been proposed as a marker of early efficacy of antiretroviral therapy (ART) and a possible predictor of late efficacy. We compared the rate of pVL decline in patients starting ART with nevirapine (NVP), efavirenz (EFV), or both drugs combined in addition to lamivudine (3TC) and stavudine (d4T). METHODS: Analysis of the viral decay constant (VDc) during the first 2 weeks of treatment in patients enrolled in the 2NN study who remained on allocated treatment. RESULTS: The median VDc (log10 copies per day, [interquartile range]) was similar for NVP (0.30 [0.25-0.36], EFV (0.31 [0.27-0.37]), and NVP + EFV (0.30 [0.27-0.36]). Patients with a baseline pVL >100,000 copies/mL were 8.7 (95% confidence interval [CI]: 6.2-12.3) times more likely to have a VDc >75th percentile. A high VDc was not associated with plasma drug concentration or with a decreased risk of virologic failure at week 48 after the start of therapy (hazard ratio = 0.8, 95% CI: 0.6-1.2). CONCLUSION: NVP, EFV, or NVP + EFV in combination with 3TC and d4T show similar rates of pVL decline during the first 2 weeks of treatment. The VDc with these regimens is not predictive of late virologic efficacy.  相似文献   
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Mechanisms of adeno-associated virus genome encapsidation   总被引:1,自引:0,他引:1  
The defective parvovirus, adeno-associated virus (AAV), is under close scrutiny as a human gene therapy vector. AAV's non-pathogenic character, reliance on helper virus co-infection for replication and wide tissue tropism, make it an appealing vector system. The virus' simplicity and ability to generate high titer vector preparations have contributed to its wide spread use in the gene therapy community. The single stranded AAV DNA genome is encased in a 20-25 nm diameter, icosahedral protein capsid. Assembly of AAV occurs in two distinct phases. First, the three capsid proteins, VP1-3, are rapidly synthesized and assembled into an empty virion in the nucleus. In the second, rate-limiting phase, single-strand genomic DNA is inserted into pre-formed capsids. Our rudimentary knowledge of these two phases comes from radioactive labeling pulse-chase experiments, cellular fractionation and immunocytological analysis of infected cells. Although the overall pattern of virus assembly and encapsidation is known, the biochemical mechanisms involved in these processes are not understood. Elucidation of the processes of capsid assembly and encapsidation may lead to improved vector production. While all of the parvoviruses share the characteristic icosahedral particle, differences in their surface topologies dictate different receptor binding and tissue tropism. Based on the analysis of the molecular structures of the parvoviruses and capsid mutagenesis studies, investigators have manipulated the capsid to change tissue tropism and to target different cell types, thus expanding the targeting potential of AAV vectors.  相似文献   
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Aim: To determine whether growth, feeding tolerance and infectious events of preterm infants is related to the proportion of intake of mother’s own raw milk (maternal milk) versus pooled pasteurized banked breast milk (donor milk). Methods: This is a prospective observational study of 55 premature infants born less than 32 weeks of gestational age admitted to the neonatal intensive care unit at the Children’s Hospital of Toulouse during two 6‐month periods from 2003 to 2005. Enrolled infants were exclusively on enteral feeds with maternal milk ± donor milk. Results: Mean gestational age was 28.6 weeks (SD 1.5) and mean birth weight 1105 grams (SD 282). During the time of exclusively breast milk feeds, weight gain (g/kg/day) was correlated to the proportion of maternal milk consumed (p = 0.0048, r = 0.4). Necrotizing enterocolitis was inversely correlated to the amount of maternal milk. The amount of maternal milk did not impact on infectious events. Conclusion: Mother’s own raw milk improves weight gain compared with donor milk in preterm infants. Lactation strategies should be sought that helps mothers to increase their milk production.  相似文献   
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