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In order to explore which amino acids or which blocks of amino acids in the 29 amino acid neuropeptide galanin are important for recognition of the endogenous ligand by galanin receptor subtypes present in the jejunum and in the hypothalamus, respectively, we have carried out L-Ala substitutions of individual amino acids or of blocks of amino acids in the rat galanin sequence and examined the binding of the obtained analogs to the rat hypothalamic and jejunal galanin receptor subtypes. This study reveals that the galanin sequence YLLGPH9–14 is essential for recognition of galanin by both the rat hypothalamic and jejunal galanin receptor subtypes. Substitution of the N-terminal amino acids, GWTL1–4, leads to total loss of affinity of galanin for both hypothalamic and jejunal galanin receptors. The α-helical C-terminal amino acid (25–29) part of galanin has no greater influence on the affinity of galanin to the hypothalamic galanin receptor subtype. L-Ala substitution of the C-terminal amino acids of galanin KHGLT25–29 shows, however, that this C-terminal motif is essential for the recognition by the jejunal galanin receptor subtype, whereas amino acids in the middle portion of galanin NSAG5–8 are of importance for binding to the hypothalamic but not to the jejunal receptor. [Ala5–8] Galanin thus has a more than 100-fold higher affinity to jejunal receptor than to the hypothalamic receptor, while [Ala25–29] galanin has a more than 100-fold higher affinity for the hypothalamic than for jejunal galanin receptor subtypes. pH dependence of the galanin binding to these receptor subtypes is also different. © Munksgaard 1997.  相似文献   
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Objective: To estimate the association between gestational diabetes mellitus (GDM) and adverse pregnancy and neonatal outcomes in Denmark.

Methods: A population-based cohort study including all singleton pregnancies in Denmark from 2004 to 2010 (n?=?403?092). Maternal complications during pregnancy and delivery and fetal complications were classified according to the International Classification of Diseases 10th Revision.

Results: The final study population consisted of 398?623 women. Of these, 9014 (2.3%) had GDM. Data were adjusted for maternal age, parity, smoking, gestational age, birth weight, BMI, gender of the fetus and calendar year. The risk of preeclampsia, caesarean section (both planned and emergency) and shoulder dystocia was increased in women with GDM. In the unadjusted analysis, the risk of thrombosis was increased by a factor 2 in the GDM patients, but in the adjusted analysis this association disappeared. Post-partum hemorrhage was similar in the two groups. The GDM women had an increased risk of giving birth to a macrosomic neonate although the unadjusted analysis did not show any difference between the two groups. Low Apgar score was increased in the GDM, but this association disappeared in the adjusted analysis. Stillbirth was comparable in the two groups.

Conclusions: Women with GDM still have increased incidence of obstetric and neonatal complications, which could imply that treatment of women with GDM should be tightened.  相似文献   
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Introduction and hypothesis

The aim of this study was to evaluate the impact of urogynecological surgery on quality of life based on patient reported outcome measures (PROMs).

Methods

Data were retrieved from the Danish Urogynaecological Database. Inclusion criteria were Danish women undergoing surgery for urinary incontinence (UI) or pelvic organ prolapse (POP) from 2006 to 2011. Using frequency of symptoms and a visual analogue scale (VAS) both pre- and postoperatively, their severity of symptoms and quality of life were measured by questionnaires.

Results

During the study period, 20,629 urogynecological procedures were performed. The questionnaires on severity of symptoms and the VAS had been completed both pre- and postoperatively for approximately one third of women undergoing surgery. For UI surgery, 83 % had improved symptoms, 13 % were unchanged, and 4 % had worse symptoms postoperatively. For POP surgery, 80, 17, and 3 % were improved, unchanged, and worsened, respectively. The postoperative bother of symptoms and interference in everyday life evaluated by VAS were significantly reduced for both UI [preoperative median VAS score 9, postoperative median score 1 (p?<?0.001)] and POP [8 preoperatively and 0 postoperatively (p?<?0.001)].

Conclusions

Based on PROMs, surgery for UI and POP is effective in alleviating symptoms associated with UI or POP, and it can improve quality of life in symptomatic women. Pre- and postoperative questionnaires are useful tools in assessing symptomatic outcome measures after surgery.  相似文献   
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The role of hepatitis B virus (HBV) genotypes in the outcome of acute HBV infection is unclear. In this study, we aimed to evaluate the clinical and virological features of patients with hepatitis B-related acute liver failure (HBV-ALF) in the US. Clinical and laboratory features of consecutive patients with HBV-ALF from the US ALF Study Group were analysed. Prevalence of HBV genotypes, precore stop (G1896A) and core promoter dual (T1762A, A1764T) variants among patients with HBV-ALF were compared with a cohort of 530 patients with chronic HBV infection. Thirty-four HBV-ALF patients were studied: mean age 41 years, 56% men, 25 had detectable HBV-DNA. HBV genotypes A, B, C and D were found in 36, 24, 8 and 32% patients, respectively. Precore stop and core promoter dual variants were detected in 32 and 44% of patients, respectively. Twenty-three (68%) patients survived: 14 after liver transplant, nine without transplant. Older age was the only independent factor associated with poor outcome. Compared with patients with chronic HBV infection, patients with ALF were more likely to be non-Asians (88% vs 44%, P = 0.005) and to have genotype D (32% vs 10%, P < 0.01). A higher prevalence of HBV genotype D persisted even after matching for race and HBeAg status (32% vs 16%, P = 0.007). We concluded that HBV genotype D was more frequently found in patients with HBV-ALF than those with chronic HBV infection in the US. Further studies are needed to determine if HBV genotypes play a role in the outcome of acute HBV infection.  相似文献   
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[structure: see text] Chloral hydrate is used medically as a sedative or hypnotic and as a rubefacient in topical preparations, and it is often given to children as a sedative during dental and other medical procedures. Chloral hydrate is used as a central nervous system depressant and sedative in veterinary medicine and as a general anesthetic in cattle and horses. It is a byproduct of the chlorination of water and has been detected in plant effluent after the bleaching of softwood pulp. Chloral, the anhydrous form of chloral hydrate, is used as a synthetic intermediate in the production of insecticides and herbicides. Chloral hydrate was nominated for study by the Food and Drug Administration based upon widespread human exposure and its potential hepatotoxicity and the toxicity of related chemicals. A dietary control component was incorporated in response to concerns within the regulatory community relating to increased background neoplasm incidences in rodent strains used for toxicity testing and to the proposed use of dietary restriction to control background neoplasm incidence in rodent cancer studies. Male B6C3F1 mice (ad libitum-fed or dietary-controlled) received chloral hydrate (99% pure) by gavage for 2 years. 2-YEAR STUDY IN MALE MICE: Groups of 120 male mice received chloral hydrate in distilled water by gavage at doses of 0, 25, 50, or 100 mg/kg 5 days per week for 104 to 105 weeks. Each dose group was divided into two dietary groups of 60 mice. The ad libitum-fed mice had free access to feed, and the dietary-controlled mice received feed in measured daily amounts calculated to maintain body weight on a previously computed idealized body weight curve. Twelve mice from each diet and dose group were evaluated at 15 months. SURVIVAL, FEED CONSUMPTION, AND BODY WEIGHTS: Survival of dosed groups of ad libitum-fed and dietary-controlled mice was similar to that of the corresponding vehicle controls. When compared to the ad libitum-fed groups, dietary control significantly increased survival in the vehicle controls and 25 and 50 mg/kg groups. Mean body weights of all dosed groups were similar to those of the vehicle control groups throughout the study. The dietary-controlled mice were successfully maintained at or near their target idealized body weights. There was less individual variation in body weights in the dietary-controlled groups than in the corresponding ad libitum-fed groups. Feed consumption by 25 and 50 mg/kg ad libitum-fed mice was generally similar to that by the vehicle controls throughout the study. Feed consumption by 100 mg/kg ad libitum-fed mice was slightly less than that by the vehicle controls throughout the study. HEPATIC ENZYME ANALYSIS: Chloral hydrate did not significantly induce either lauric acid 4-hydroxylase activity or CYP4A immunoreactive protein in any of the dosed groups of ad libitum-fed mice. However, 100 mg/kg did significantly induce both lauric acid 4-hydroxylase activity and CYP4A immunoreactive protein in the dietary-controlled mice. Moreover, the induction response profile of CYP4A was similar to the increase in the incidence of liver neoplasms at 2 years in the dietary-controlled mice with the major effect occurring in the 100 mg/kg group. The serum enzymes alanine aminotransferase, amylase, aspartate aminotransferase, and lactate dehydrogenase were also assayed at 2 years. In the ad libitum-fed groups there was a significant increase in aspartate aminotransferase activity in the 50 mg/kg group. There were no other significant effects in any dosed group, but in general the dietary-controlled groups exhibited lower values than the corresponding ad libitum-fed groups. ORGAN WEIGHTS AND PATHOLOGY FINDINGS: The heart weight of ad libitum-fed male mice administered 100 mg/kg and the kidney weights of 50 and 100 mg/kg ad libitum-fed mice were significantly less than those of the vehicle controls at 2 years. The liver weights of all dosed groups of ad libitum-fed and dietary-controlled mice were greater than those of the vehicle control groups at 2 years, but the increases were not statistically significant. The incidence of hepatocellular adenoma or carcinoma (combined) in ad libitum-fed mice administered 25 mg/kg was significantly greater than that in the vehicle controls at 2 years. The incidences of hepatocellular carcinoma and of hepatocellular adenoma or carcinoma (combined) occurred with positive trends in dietary-controlled male mice at 2 years, and the incidence of hepatocellular carcinoma in 100 mg/kg dietary-controlled mice was significantly increased. CONCLUSIONS: Under the conditions used in this 2-year gavage study, there was some evidence of carcinogenic activity of chloral hydrate in male B6C3F1 mice based on increased incidences of hepatocellular adenoma or carcinoma (combined) in ad libitum-fed mice and on increased incidences of hepatocellular carcinoma in dietary-controlled mice. In the dietary-controlled mice, induction of enzymes associated with peroxisome proliferation was observed at higher doses.  相似文献   
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Background Lymphatic mapping and sentinel lymphadenectomy (LM/SL) provide important prognostic information for patients with early-stage melanoma. Although the use of this technique in patients with thin melanomas (1.00 mm) is not routine, risk factors that may predict sentinel lymph node (SLN) positivity in this patient population are under investigation. We sought to determine whether mitotic rate (MR) is associated with SLN positivity in thin-melanoma patients and, therefore, whether it may be used to risk-stratify and select patients for LM/SL.Methods Clinical and histopathologic variables were reviewed for 181 patients with thin melanomas who underwent LM/SL from January 1996 through January 2004. Univariate and multivariate logistic regression analyses were performed to identify factors associated with SLN positivity. Risk groups were defined on the basis of the development of a classification tree.Results The overall SLN positivity rate was 5%. All patients with positive SLNs had an MR of >0. By univariate analysis, MR and thickness were significant predictors of SLN positivity. The association between MR and SLN positivity remained significant controlling for each of the other variables evaluated. On the basis of a classification tree, patients with an MR >0 and tumor thickness .76 mm were identified as a higher-risk group, with an SLN positivity rate of 12.3%.Conclusions In patients with thin melanomas, MR >0 seems to be a significant predictor of SLN positivity that may be used to risk-stratify and select patients for LM/SL. To confirm these results, the predictive value of MR for SLN positivity needs to be validated in other populations of thin-melanoma patients.Published by Springer Science+Business Media, Inc. © 2005 The Society of Surgical Oncology, Inc.  相似文献   
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Background Isolated hepatic perfusion has been used in patients with colorectal cancer (CRC) metastatic to the liver. We sought to determine whether perfusion with antisense oligodeoxynucleotides results in the downregulation of β-catenin and whether this improves tumor response to isolated limb perfusion (ILP) in a heterotopic model of human CRC.Methods Adenomatous polyposis coli–mutant human CRC xenografts were implanted into athymic rats. Animals were randomized to the following groups: (1) no treatment, (2) control ILP, (3) melphalan ILP, (4) ILP with antisense specific for β-catenin, (5) ILP with nonspecific antisense, and (6) melphalan plus β-catenin–specific antisense ILP. Tumor response and Western blot analysis of protein expression were evaluated.Results The maximal decrease (mean ± SE) in tumor volume was 0% ± 10% for no treatment, 19% ± 14% for control ILP, 58% ± 3% for melphalan ILP, 58% ± 9% for β-catenin–specific ILP, 13% ± 19% for nonspecific antisense ILP, and 73% ± 6% for melphalan plus β-catenin–specific ILP (P < .05 for melphalan ILP, β-catenin–specific ILP, and melphalan plus antisense ILP). Tumor regrowth was delayed for 6 days after control ILP, 24 days after melphalan ILP, 20 days after β-catenin–specific ILP, 10 days after nonspecific antisense ILP, and 60 days after melphalan plus β-catenin–specific ILP (P < .05 for melphalan plus β-catenin–specific ILP compared with all others). Western blotting revealed prolonged suppression of β-catenin expression after β-catenin–specific ILP.Conclusions Short-term β-catenin antisense treatment improves tumor response rates after ILP in a rodent model of human CRC.Presented in part at the Surgical Forum of the American College of Surgeons, Chicago, Illinois, October 19–23, 2003.  相似文献   
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