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991.
NAPLES, ITALY     
Purpose : To assess the clinical and biological effect of the preincubation of oocytes in follicular fluid prior to IVF and ICSI cycles. Methods : A series of patients were treated by the preincubation of oocytes in the patients’ follicular fluid for 3 h after oocyte retrieval followed by processing with standard protocols. Control oocytes were preincubated in normal IVF culture medium. Fluorescence techniques were used to examine oocyte mitochondrial membrane potential. Results : Fertilisation, pregnancy, and implantation rates were all significantly improved after the preincubation of oocytes in follicular fluid. Further tests suggested that differences in pH between follicular fluid and artificial culture medium may be critical to these differences. Conclusions : Preincubation of human oocytes in follicular fluid improves the results after IVF. This may be partly due to the use of a non-“physiological” pH in artificial culture media during in vitro fertilisation procedures.  相似文献   
992.
The nonclassical human leukocyte antigen (HLA) class Ib gene HLA-G may be important for the induction and maintenance of immune tolerance between the mother and the semi-allogeneic fetus during pregnancy. Expression of HLA-G can influence cytokine and cytotoxic T-lymphocyte responses. Different HLA-G mRNA isoform expression patterns have been associated with HLA-G polymorphism, especially with a 14-bp insertion deletion polymorphism in the 3' untranslated region (3'UTR) of the HLA-G gene. A significantly high level of interleukin-10 (IL-10) secretion is observed in homozygous +14/+14-bp HLA-G peripheral blood mononuclear cells after lipopolysaccharide (LPS) stimulation. This study finds that polymorphism in the 5' upstream regulatory region (5'URR) of the HLA-G gene may also be implicated in differences in IL-10 secretion. However, this may also be due to linkage disequilibrium with the 14-bp polymorphism. A single-nucleotide polymorphism located -477 bp from the start site of exon 1 had a significant association with IL-10 concentrations but not after correction (p=0.011; pc=0.154). This polymorphism is located next to a heat shock element. Eighteen 5'-URR/3'-UTR HLA-G haplotypes were defined; one common homozygous genotype based on these haplotypes was significantly associated with a high IL-10 level after LPS stimulation compared to certain other genotypes. This study indicates that polymorphism in the 5'-URR of the HLA-G gene may have functional significance, although a new line of investigations is needed to elucidate these findings.  相似文献   
993.
OBJECTIVES: To test the applicability and safety of a standardized diagnostic algorithm in geriatric departments and to define the prevalence of different causes of syncope in older patients. DESIGN: Multicenter cross-sectional observational study. SETTING: In-hospital geriatric acute care departments and outpatient clinics. PARTICIPANTS: Two hundred forty-two patients (aged>or=65, mean+/-standard deviation=79+/-7, range 65-98) consecutively referred for evaluation of transient loss of consciousness to any of six clinical centers participating in the study. Of these, 11 had a syncope-like condition (5 transient ischemic attack; 6 seizures), and 231 had syncope (aged 65-74, n=71; aged>or=75, n=160). MEASUREMENTS: Protocol designed to define etiology and clinical characteristics of syncope derived from European Society of Cardiology Guidelines on syncope. RESULTS: No major complication occurred with use of the protocol. Neurally mediated was the more prevalent form of syncope in this population (66.6%). Cardiac causes accounted for 14.7% of all cases. The neuroreflex form of syncope (vasovagal, situational, and carotid sinus syndrome) was more common in younger than in older patients (62.3% vs 36.2%; P=.001), whereas orthostatic syncope was more frequent in the older than in the younger group (30.5% vs 4.2%; P<.001). In only 10.4% of cases, syncope remained of unexplained origin. After initial evaluation, a definite diagnosis was possible in 40.1% of the cases, and a suspected diagnosis was obtained in 57.9%. Syncope of suspected cardiac origin after initial evaluation was confirmed in 43.7% of cases, and neuromediated causes were confirmed in 83.5% of the cases. CONCLUSION: The protocol is applicable even beyond the age of 90 in geriatric departments. The standardized protocol is associated with a reduction in the frequency of unexplained syncope to about 10%.  相似文献   
994.
OBJECTIVES: (1) To examine the concurrent criterion validity of the modified shuttle walk test (MSWT) by using the 6- (6MWT) and 12-minute walk test (12MWT), (2) to examine the concurrent criterion validity of the estimated maximum oxygen uptake (Vo2max) of the MSWT with actual Vo2max, and (3) to determine test-retest reliability of the MSWT in patients with chronic obstructive pulmonary disease (COPD). DESIGN: Validation study. SETTING: Outpatient pulmonary rehabilitation program. PARTICIPANTS: Thirty clinically stable adults with COPD. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Subjects were randomly assigned to receive either the 6MWT and 12MWT or the MSWT first. The MSWT was repeated 1 week later (N = 30). Estimated Vo2max was calculated, and actual Vo2max was conducted by using the Jones test. Validity of the MSWT was assessed by comparing endurance scores and Vo2max with results from the 6MWT and 12MWT and Jones test, respectively. RESULTS: There was a moderately high correlation between the MSWT and the 6MWT and 12MWT at initial testing (.82 and .74, respectively). Correlation between estimated and actual Vo2max was r equal to .68. Test-retest reliability for the entire sample was high (intraclass correlation coefficient, .88). Results remained quite stable across severity, age, and sex subgroups. CONCLUSIONS: The MSWT is a standardized externally paced submaximal endurance walking test. The results indicate that the MSWT has high concurrent validity and test-retest reliability for patients with COPD.  相似文献   
995.
996.
Antibodies raised against human alpha2-6 and beta2-4 nicotinic receptor subunits were utilized to fractionate (3)H-epibatidine binding in human temporal cortex and striatum. The predominant receptor subtypes in both regions contained alpha4 and beta2 subunits. In normal cortex, 10% of binding was also associated with alpha2 subunits, whereas in the striatum, contributions by alpha6 (17%) and beta3 (23%) were observed. Minimal binding (< or =5%) was associated with alpha3. In Alzheimer's disease and dementia with Lewy bodies, cortical loss of binding was associated with reductions in alpha4 (50%, P < 0.01) and beta2 (30-38%, P < 0.05). In Parkinson's disease and dementia with Lewy bodies, striatal deficits in alpha6 (91 and 59% respectively, P < 0.01) and beta3 (72 and 75%, P < 0.05) tended to be greater than for alpha4 and beta2 (50-58%, P < 0.05). This study demonstrates distinct combinations of subunits contributing to heteromeric nicotinic receptor binding in the human brain that are area/pathway specific and differentially affected by neurodegeneration.  相似文献   
997.
The Italian preadolescent mental health project (PrISMA--Progetto Italiano Salute Mentale Adolescenti) is the first Italian study designed to estimate the prevalence of mental disorders in preadolescents (10-14 years old) living in urban areas, and to analyse the demographic and biological correlates of emotional and behavioural problems. This paper describes the rationale, methods and the analysis plan of the project. The design of the study used a two-stage sampling procedure, one screening stage of emotional and behavioural problems in a large sample of subjects attending public and private schools and a second stage of diagnostic assessment in a sample including all high scorers and a proportion of low scorers. In the screening stage, parents of preadolescents were asked to fill in the Child Behavior Checklist (CBCL), whereas in the second stage preadolescents and their parents were administered the Development and Well Being Assessment for the assessment of mental disorders together with the Strengths and Difficulties Questionnaire and two scales (C-GAS and HoNOSCA) designed to evaluate the functioning of the preadolescent in different areas. Genetic samples were collected during the screening stage, after parents gave their informed written consent. The findings of this study are expected to allow an adequate planning of interventions for the prevention and the treatment of mental disorders in preadolescence as well as efficient health services.  相似文献   
998.
999.
Doxorubicin (DOXO) is an anthracycline antibiotic which is used in the treatment of human malignancies such as leukemia, lymphoma and a number of solid tumors, particularly breast cancer.  相似文献   
1000.

Background and purpose:

We showed previously that a new Pt(II) complex ([Pt(O,O′-acac)(γ-acac)(DMS)]) exerted high and fast apoptotic processes in MCF-7 cells. The objective of this study was to investigate the hypothesis that [Pt(O,O′-acac)(γ-acac)(DMS)] is also able to exert anoikis and alter the migration ability of MCF-7 cells, and to show some of the signalling events leading to these alterations.

Experimental approach:

Cells were treated with sublethal doses of [Pt(O,O′-acac)(γ-acac)(DMS)], and the efficiency of colony initiation and anchorage-independent growth was assayed; cell migration was examined by in vitro culture wounding assay. Gelatin zymography for MMP-2 and -9 activities, Western blottings of MMPs, MAPKs, Src, PKC-ε and FAK, after [Pt(O,O′-acac)(γ-acac)(DMS)] treatment, were also performed.

Key results:

Sub-cytotoxic drug concentrations decreased the: (i) anchorage-dependent and -independent growth; (ii) migration ability; and (iii) expression and activity of MMP-2 and MMP-9. [Pt(O,O′-acac)(γ-acac)(DMS)] provoked the generation of reactive oxygen species (ROS), and the activation of p38MAPK, Src and PKC-ε. p38MAPK phosphorylation, cell anoikis and migration due to [Pt(O,O′-acac)(γ-acac)(DMS)] were blocked by PKC-ε inhibition. Furthermore, Src inhibition blocked the [Pt(O,O′-acac)(γ-acac)(DMS)]-provoked activation of PKC-ε, while ROS generation blockage inhibited the activation of Src, and also the decrement of phosphorylated FAK observed in detached [Pt(O,O′-acac)(γ-acac)(DMS)]-treated cells.

Conclusions and implications:

Sublethal concentrations of [Pt(O,O′-acac)(γ-acac)(DMS)] induced anoikis and prevented events leading to metastasis via alterations in cell migration, anchorage independency, stromal interactions and MMP activity. Hence, [Pt(O,O′-acac)(γ-acac)(DMS)] may be a promising therapeutic agent for preventing growth and metastasis of breast cancer.  相似文献   
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