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Background

Use of exogenous surfactant in congenital diaphragmatic hernia (CDH) patients is routine in many centers. The authors sought to determine the impact of surfactant use in the premature infant with CDH.

Methods

Data on liveborn infants with CDH from participating institutions were collected prospectively. Surfactant use and timing and outcome data were analyzed retrospectively. The authors evaluated the prenatal diagnosis patients as well. The outcome variable was survival to discharge. Odds ratios with confidence intervals were calculated.

Results

Five hundred ten infants less than 37 weeks’ gestation were entered in the CDH registry. Infants with severe anomalies (n = 80) were excluded. Information on surfactant use was available for 424 patients. Infants receiving surfactant (n = 209) had a greater odds of death than infants not receiving surfactant (n = 215, odds ratio, 2.17, 95% CI: 1.5 to 3.2; P < .01). In prenatally diagnosed infants with immediate distress, there was a trend toward worse survival rates among those receiving surfactant at 1 hour (52 patients) versus those that did not (93 patients; odds ratio, 1.93, 95% CI: 0.96 to 3.9; P < .07).

Conclusions

Surfactant, as currently used, is associated with a lower survival rate in preterm infants with CDH. The use of surfactant replacement in premature infants with CDH can be recommended only within the context of a randomized clinical trial.  相似文献   
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The potential role of tau protein O-glycosylation in Alzheimer's disease   总被引:6,自引:0,他引:6  
Single O-linked N-acetylglucosamine (O-GlcNAc) sugar residues can compete with phosphate groups to occupy specific sites on certain nuclear and cytosolic proteins. Here we show that inhibiting cellular kinase activities resulted in changes in protein O-glycosylation levels in heat-stable cytoskeletal protein fractions derived from primary neuronal cells. As increased phosphorylation of the microtubule-associated protein tau is one of the pathological hallmarks of Alzheimer's disease and glycosylation may play an influential role in this process. We observed a significant decrease in the protein O-GlcNAc glycosylation of a tau-enriched cytoskeletal fraction generated from AD post-mortem brain samples as compared with control, suggesting an inverse relationship between the two post-translational modifications. Finally, cells transfected with the cDNA coding for O-GlcNAc transferase (OGT) displayed altered tau phosphorylation patterns as compared with control cells, suggesting that changes in tau glycosylation may influence its phosphorylation state. The specificity of the changes in the phosphorylation of individual amino acid residues provides evidence for a targeted O-glycosylation of tau.  相似文献   
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INTRODUCTION: Palliative treatment for nondisseminated unresectable peripheral cholangiocarcinoma (PCC) carries a 0% 5-year survival rate. The role of orthotopic liver transplantation (OLT) in these patients is controversial because the survival rate is lower than with other indications for transplantation and the lack of available donor organs. The aim of this paper was to review the Spanish experience in OLT for PCC to identify prognostic factors for survival. METHODS: We retrospectively reviewed 23 patients undergoing OLT in Spain for PCC over a period of 13 years. RESULTS: The actuarial survival rates were 77%, 65%, and 42% at 1, 3, and 5 years, respectively. The main cause of death was tumor recurrence (35%). Prognotic factors for an adverse outcome were pTNM classification (P<.05) in the univariate analysis and perineural invasion (P<.05) and stages III or IVA (P<.05) in the multivariate analysis. CONCLUSIONS: OLT for nondisseminated irresectable PCC displays higher survival rates at 3 and 5 years than palliative treatments, especially for tumors in the initial stages, which means that more information is needed to help better select PCC patients for transplantation.  相似文献   
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Two cases of trisomy 4 mosaicism are reported including one with molecularly confirmed uniparental disomy (UPD) of chromosome 4. Cytogenetic analysis of a chorionic villus sample (CVS) in Case 1 showed complete trisomy 4 in trophoblast and diploidy in chorionic stroma. Amniotic fluid analysis demonstrated a 46,XX complement. After intrauterine fetal death at 30 weeks, molecular analysis confirmed the presence of trisomy 4 of maternal meiotic origin, while fetal tissues showed maternal UPD for chromosome 4. Cultured CVS in Case 2 revealed trisomy 4 in 2/30 cells analyzed. This pregnancy resulted in a healthy livebirth with biparental inheritance of chromosome 4. Molecularly confirmed UPD4 has not been previously reported, and therefore, although the adverse outcome in Case 1 is likely due to the trisomy 4 in the placenta, an imprinting effect associated with UPD4 cannot be excluded.  相似文献   
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BACKGROUND: Cognitive impairment is associated with functional impairment in patients with Alzheimer's disease (AD). Behavioural disturbance is very common in these patients. Nevertheless, there has been very little research into the relations between behavioural disturbance and functional status in AD. The purpose of this study is to investigate the relationship between behavioural disturbance and functional status after taking account of cognitive impairment. MATERIAL AND METHODS: 579 patients were prospectively evaluated at 16 French hospitals, all referents for AD, and were diagnosed with possible or probable AD. These patients were assessed with NeuroPsychiatric Inventory (NPI), cognitive subscales of the Alzheimer's Disease Assessment Scale (ADAS-cog), Clinical Dementia Rating scale (CDR) and Instrumental Activities of Daily Living scale (IADL). RESULTS: The number of men with available data for IADL total score was too small to make any analysis. 'Group A' gathered 256 women for whom the relation between autonomy for Activities of Daily Living (ADL) and the other variables were determined. 'Group B', pooled 85 women for whom relations found were verified. Linear regression was used for the analysis. With age, cognitive impairment allows us to explain best (38%) the loss of autonomy for ADL. CONCLUSION: The role of behavioural disturbances in the loss of autonomy for ADL was not determinant in our study, whereas cognitive impairment and age were better able to determine the loss of autonomy for ADL. Further study is needed to explain the decline of functional status in AD patients.  相似文献   
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