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61.
CONTEXT: Previous studies showed that nerve growth factor (NGF) induces the expression of functional FSH receptors (FSHR) in preantral follicles of the developing rat ovary. OBJECTIVE: The objective of this study was to determine whether NGF can affect granulosa cell (GC) function in human periovulatory follicles using intact human ovaries and isolated human GCs. PATIENTS AND INTERVENTIONS: Human GCs were obtained from in vitro fertilization patients and normal ovaries from women with elective pelvic surgery for nonovarian indications. Results: In normal ovaries, NGF and trkA (NGF's high-affinity receptor) were detected by immunohistochemistry in GCs of preantral and antral follicles. NGF and trkA are also present in thecal cells of antral follicles. Both freshly collected and cultured GCs contained immunoreactive NGF and trkA in addition to their respective mRNAs. Human GCs respond to NGF with increased estradiol (E(2)) secretion and a reduction in progesterone output. Exposure of human GCs to NGF increased FSHR mRNA content within 18 h of treatment, and this effect was blocked by the trk tyrosine kinase blocker K-252a. Also, cells preexposed to NGF released significantly more E(2) in response to hFSH than cells not pretreated with the neurotropin, showing that the NGF-induced increase in FSHR gene expression results in the formation of functional FSHRs. CONCLUSIONS: These results suggest that one of the functions of NGF in the preovulatory human ovary is to increase the secretion of E(2) while preventing early luteinization via an inhibitory effect on progesterone secretion. NGF stimulates E(2) secretion both directly and by increasing the formation of FSHRs.  相似文献   
62.
The balance between excitatory and inhibitory synapses is crucial for normal brain function. Wnt proteins stimulate synapse formation by increasing synaptic assembly. However, it is unclear whether Wnt signaling differentially regulates the formation of excitatory and inhibitory synapses. Here, we demonstrate that Wnt7a preferentially stimulates excitatory synapse formation and function. In hippocampal neurons, Wnt7a increases the number of excitatory synapses, whereas inhibitory synapses are unaffected. Wnt7a or postsynaptic expression of Dishevelled-1 (Dvl1), a core Wnt signaling component, increases the frequency and amplitude of miniature excitatory postsynaptic currents (mEPSCs), but not miniature inhibitory postsynaptic currents (mIPSCs). Wnt7a increases the density and maturity of dendritic spines, whereas Wnt7a-Dvl1-deficient mice exhibit defects in spine morphogenesis and mossy fiber-CA3 synaptic transmission in the hippocampus. Using a postsynaptic reporter for Ca(2+)/Calmodulin-dependent protein kinase II (CaMKII) activity, we demonstrate that Wnt7a rapidly activates CaMKII in spines. Importantly, CaMKII inhibition abolishes the effects of Wnt7a on spine growth and excitatory synaptic strength. These data indicate that Wnt7a signaling is critical to regulate spine growth and synaptic strength through the local activation of CaMKII at dendritic spines. Therefore, aberrant Wnt7a signaling may contribute to neurological disorders in which excitatory signaling is disrupted.  相似文献   
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Centers for Disease Control and Prevention (CDC) has recommended integrating behavioral interventions into medical care settings for persons living with HIV. Delivering an intensive, family-based intervention for mothers living with HIV (MLH) (n = 173) and their adolescent children (n = 116) integrated into medical care was problematic. Despite the fact that nearly half of MLH were recruited at HIV/AIDS clinics, community centers and children’s hospitals were the most popular and most successful sites for the delivery of the intervention. We provide recommendations for how to integrate intensive interventions into medical care, given the needs of MLH, their adolescents, and the organizations serving them.  相似文献   
65.
The association between inflammation, platelets, and patent ductus arteriosus (PDA) has not been studied so far. The purpose of this study was to evaluate whether C-reactive protein (CRP) is related to low platelet count and PDA. This was a retrospective study of 88 infants with a birth weight ≤1500 g and a gestational age ≤30 weeks. Platelet count, CRP, and an echocardiogram were assessed in all infants. The subjects were matched by sex, gestational age, and birth weight. Differences were compared using the χ2, t-test, or Mann–Whitney U-test, as appropriate. Significant variables were entered into a logistic regression model. The association between CRP and platelets was evaluated by correlation and regression analysis. Platelet count (167 000 vs. 213 000 µl?1, p = 0.015) was lower and the CRP (0.45 vs. 0.20 mg/dl, p = 0.002) was higher, and the platelet count correlated inversely with CRP (r = ?0.145, p = 0.049) in the infants with vs. without PDA. Only CRP was independently associated with PDA in a logistic regression model (OR 64.1, 95% confidence interval 1.4–2941, p = 0.033).  相似文献   
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IntroductionScales for predicting venous thromboembolism (VTE) recurrence are useful for deciding the duration of the anticoagulant treatment. Although there are several scales, the most appropriate for our setting has not been identified. For this reason, we aimed to validate the DASH prediction score and the Vienna nomogram at 12 months.MethodsThis was a retrospective study of unselected consecutive VTE patients seen between 2006 and 2014. We compared the ability of the DASH score and the Vienna nomogram to predict recurrences of VTE. The validation was performed by stratifying patients as low-risk or high-risk, according to each scale (discrimination) and comparing the observed recurrence with the expected rate (calibration).ResultsOf 353 patients evaluated, 195 were analyzed, with an average age of 53.5 ± 19 years. There were 21 recurrences in 1 year (10.8%, 95% CI: 6.8%-16%). According to the DASH score, 42% were classified as low risk, and the rate of VTE recurrence in this group was 4.9% (95% CI: 1.3%-12%) vs. the high-risk group that was 15% (95% CI: 9%-23%) (p <.05). According to the Vienna nomogram, 30% were classified as low risk, and the rate of VTE recurrence in the low risk group vs. the high risk group was 4.2% (95% CI:0.5%-14%) vs. 16.2% (95% CI: 9.9%-24.4%) (p <.05).ConclusionsOur study validates the DASH score and the Vienna nomogram in our population. The DASH prediction score may be the most advisable, both because of its simplicity and its ability to identify more low-risk patients than the Vienna nomogram (42% vs. 30%).  相似文献   
68.
Two-field radical lymphadenectomy in the treatment of esophageal carcinoma   总被引:2,自引:0,他引:2  
This paper retrospectively compares post-operative complications, mortality and long-term survival of patients with esophageal carcinoma who were treated with standard esophagectomy or with extended two-field lymph node clearance. Fifty-seven patients with resectable esophageal carcinoma were included in the study. Twenty-eight patients were submitted to a radical two-field esophagectomy and lymphadenectomy, while the remaining 29 were submitted to a standard, more conservative, esophagectomy performed mostly through a transhiatal route. The two groups of patients were similar in all clinical, laboratory and pathologic features. There was a significant lower anastomotic leakage rate in the group of patients submitted to a radical lymph node resection; post-operative respiratory complication rate and mortality were similar in both groups. The overall 5-year survival was 20%. When lymph node resection was performed, the 5-year survival rate rose to 36%; it was 44% when nodal involvement was negative and 19% for N1 patients; when standard esophagectomy was the procedure, these figures were 9% (p < 0.05), and 6% respectively.  相似文献   
69.
DL-alpha-Difluoromethylornithine is an enzyme-activated inhibitor of ornithine decarboxylase and an antagonist of polyamine metabolism that has been successful in clinical trials against West African sleeping sickness caused by Trypanosoma brucei gambiense. Its potential for use against the more virulent East African form of the disease, caused by T. brucei rhodesiense, is not certain. We examined 14 East African clinical isolates from the Kenya Trypanosomiasis Research Institute strain bank plus 2 established isolates for susceptibility to DL-alpha-difluoromethylornithine and to standard trypanocides. Seven of 16 strains were partially or totally refractory to DL-alpha-difluoromethylornithine in our test system. Four strains were also refractory to arsenical drugs, and five were refractory to diamidines. The results indicate that other novel agents or combinations of established agents may be needed for chemotherapy of East African disease.  相似文献   
70.
A mixed keratitis due to Acanthamoeba and Hartmannella species is reported. The patient was a soft contact lens wearer. Early diagnosis was achieved by polymerase chain reaction and culture. The pathogenic potential of the isolated amoebae was proven using cytotoxicity assays. The reported case underlines the difficulties in identifying a corneal amoebic infection. In our case, the early diagnosis of a mixed infection allowed a proper antiamoebic treatment in an early stage of infection. This may have been the reason of a successful outcome after therapy.  相似文献   
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