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21.
The anxiolytic profile of dexmedetomidine, a novel, highly-selective 2-adrenergic agonist, was examined in rats in the elevated plus-maze test when administered either alone or in combination with the benzodiazepine agonist midazolam. Dexmedetomidine, 0.1–10 µg/kg, was inactive in modifying the rats' behavioral response in this test. Midazolam, 0.1–10 mg/kg, dose-dependently produced an anxiolytic-like profile characterized by an increased time spent in the open arms of the elevated plus-maze. A combination of dexmedetomidine 0.5 µg/kg and midazolam 0.5 mg/kg produced a synergistic interaction. This heterergic interaction of dexmedetomidine on midazolam's anxiolytic-like profile was dose-dependently blocked by pretreatment with an 2-adrenergic antagonist, atipamezole, 10–50 µg/kg, and a benzodiazepine antagonist flumazenil, 1.0 and 10 mg/kg, but not by the 1-adrenergic antagonist, prazosin, 0.1–10 mg/kg. While the transmembrane signal transduction pathways for benzodiazepine- and 2-agonist responses do not share any molecular component, there does appear to be crosstalk between these two systems. These may involve GABA or noradrenergic downstream effects of either dexmedetomidine or midazolam, respectively.  相似文献   
22.
PURPOSE: Gastrointestinal stromal tumors (GISTs) represent a distinctive (but histologically heterogeneous) group of neoplasms, the malignant potential of which is often uncertain. To determine the prognostic relevance of p16INK4 alterations in GISTs, we investigated a larger group of GISTs and correlated the genetic findings with clinicopathological factors and patient survival. MATERIAL AND METHODS: We evaluated the methylation status of the promotor by methylation-specific polymerase chain reaction (PCR), the presence of mutations by PCR-SSCP-sequencing, the loss of heterozygosity at the p16INK4 locus (using the c5.1 marker), and the immunohistochemical expression of p16INK4 protein in 43 GISTs in 39 patients. RESULTS: p16INK4 alterations were found in 25 of 43 GISTs (58.1%), with benign, borderline, or malignant GISTs showing no differences in the type and frequency of alteration. p16INK4 alterations were correlated with a loss of p16INK4 protein expression (P <.01). Patients who had tumors with p16INK4 alterations had a poorer prognosis than patients with tumors without such alterations (P =.02). There was a high predictive value for p16INK4 alterations only in the group of benign and borderline GISTs (P <.01) with regard to clinical outcome. Univariate Cox's proportional hazard regression analysis revealed a strong correlation between p16INK4 alterations, tumor size, mitotic index, and overall survival (P <.02), whereas multivariate Cox's analysis confirmed only p16INK4 alterations as an independent prognostic factor. CONCLUSION: We believe that the evaluation of p16INK4 alteration status is a helpful prognosticator, particularly in the benign and borderline groups of GISTs.  相似文献   
23.
The effect of a high-fat meal on the oral bioavailability of deramciclane 30 mg tablet was evaluated in 18 healthy male volunteers in a randomised, single dose, two-way crossover study. The drug was administered following an overnight fast or a standardised high-fat breakfast. The plasma concentrations of deramciclane and N-desmethylderamciclane were determined by using a validated HPLC-MS -MS/MS method. An effect of food on the bioavailability was indicated if the 90% confidence interval (CI) for the ratio of geometric means of fed and fasted treatments was not contained in the equivalence limit of 0.8-1.25 for AUC and C(max). The ratios of the mean C(max) and AUC(0-infinity) values of deramciclane were 1.24 (90% CI 1.12-1.38) and 1.31 (90% CI 1.21-1.41) in fed versus fasted subjects, which overlapped but exceeded the equivalence limit. In contrast to the parent compound, the 90% CI of the mean ratios for AUC(0-infinity) and C(max) of N-desmethylderamciclane were within the predefined range. The 24 and 31% increase in C(max) and AUC(0-infinity) of deramciclane, respectively, under fed condition is modest and probably has no clinical significance since it is relatively small compared to the inter-individual variability of these parameters.  相似文献   
24.
25.

Objective

To verify whether a multidomain intervention lowers the risk of developing new chronic diseases in older adults.

Methods

Multicenter, double-blind randomized controlled trial started in October 2009, with 2-year follow-up. A total of 1260 people aged 60 to 77?years were enrolled in the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER). Participants were randomly assigned in a 1:1 ratio to a 2-year multidomain intervention (n?=?631) (nutritional guidance, exercise, cognitive training, and management of metabolic and vascular risk factors) or a control group (n?=?629) (general health advice). Data on most common chronic diseases were collected by a physician at baseline and 2?years later.

Results

At 2-year follow-up, the average number of new chronic diseases was 0.47 [standard deviation (SD) 0.7] in the intervention group and 0.58 (SD 0.8) in the control group (P?<?.01). The incidence rate per 100 person-years for developing 1+?new disease(s) was 17.4 [95% confidence interval (CI)?=?15.1-20.1] in the intervention group and 20.5 (95% CI?=?18.0-23.4) in the control group; for developing 2+?new diseases, 4.9 (95% CI?=?3.7-6.4) and 6.1 (95% CI?=?4.8-7.8); and for 3+?new diseases, 0.7 (95% CI?=?0.4-1.5) and 1.8 (95% CI?=?1.1-2.8), respectively. After adjustment for age, sex, education, current smoking, alcohol intake, and the number of chronic diseases at baseline, the intervention group had a hazard ratio ranging from 0.80 (0.66-0.98) for developing 1+?new chronic disease(s) to 0.38 (0.16-0.88) for developing 3+?new chronic diseases compared to the control group.

Conclusions

Findings from this randomized controlled trial suggest that a multidomain intervention could reduce the risk of developing new chronic diseases in older people.  相似文献   
26.
OBJECTIVE: The purpose of this study was to evaluate the clinical, pathologic, and imaging features of gastrointestinal stromal tumors that occur in patients with neurofibromatosis. CONCLUSION: Gastrointestinal stromal tumors that occur in patients with neurofibromatosis commonly originate from the proximal small intestine and are often multiple. The cross-sectional imaging appearance of gastrointestinal stromal tumors that occur in patients with neurofibromatosis is similar to that of gastrointestinal stromal tumors that occur in the general population.  相似文献   
27.
High levels of cytokines are risk factors for type 2 diabetes. Therefore, we investigated whether the promoter polymorphisms of the tumor necrosis factor-alpha (TNF-alpha; G-308A) and interleukin 6 (IL-6; C-174G) genes predict the conversion from impaired glucose tolerance (IGT) to type 2 diabetes in the Finnish Diabetes Prevention Study. Altogether, 490 overweight subjects with IGT whose DNA was available were randomly divided into one of the two treatment assignments: the control group and the intensive, individualized diet and exercise intervention group. The -308A allele of the TNF-alpha gene was associated with an approximate twofold higher risk for type 2 diabetes compared with the G-308G genotype (odds ratio 1.80, 95% CI 1.05-3.09; P = 0.034). Subjects with both the A allele of the TNF-alpha gene and the C-174C genotype of the IL-6 gene had a 2.2-fold (CI 1.02-4.85, P = 0.045) higher risk of developing type 2 diabetes than subjects without the risk genotypes. We conclude that the -308A allele of the promoter polymorphism (G-308A) of the TNF-alpha gene is a predictor for the conversion from IGT to type 2 diabetes. Furthermore, this polymorphism seems to have a gene-gene interaction with the C-174C genotype of the IL-6 gene.  相似文献   
28.
29.
Objective: To evaluate the performance of first trimester biochemical markers, pregnancy-associated plasma protein-A (PAPP-A), free beta human chorionic gonadotropin (fβ-hCG), and nuchal translucency (NT) in detection of severe congenital heart defects (CHDs).

Methods: During the study period from 1 January 2008 to 31 December 2011, biochemical markers and NT were measured in 31,144 women as part of voluntary first trimester screening program for Down’s syndrome in Northern Finland. Data for 71 severe CHD cases and 762 controls were obtained from the hospital records and from the National Medical Birth Register, which records the birth of all liveborn and stillborn infants, and from the National Register of Congenital Malformations that receives information about all the CHD cases diagnosed in Finland.

Results: Both PAPP-A and fβ-hCG multiple of median (MoM) values were decreased in all severe CHDs: 0.71 and 0.69 in ventricular septal defects (VSDs), 0.58 and 0.88 in tetralogy of Fallot cases (TOFs), 0.82 and 0.89 in hypoplastic left heart syndromes (HLHSs), and 0.88 and 0.96 in multiple defects, respectively. NT was increased in all study groups except of VSD group. ROC AUC was 0.72 for VSD when combining prior risk with PAPP-A and fβ-hCG. Adding NT did not improve the detection rate. With normal NT but decreased (<0.5 MoM) PAPP-A and fβ-hCG odds ratios for VSD and HLHS were 19.5 and 25.6, respectively.

Conclusions: Maternal serum biochemistry improves the detection of CHDs compared to NT measurement only. In cases with normal NT measurement but low concentrations of both PAPP-A and fβ-hCG, an alert for possible CHD, especially VSD, could be given with thorough examination of fetal heart in later ultrasound scans.  相似文献   

30.
This study investigated changes in perceived depression, anxiety and loneliness during a 16-year follow-up among elderly Jyväskylä residents born in 1914-1923. A further concern was with how perceived atmosphere in the formative environment was reflected in depression, anxiety and loneliness in old age. The first phase of the study took place in 1988 when interviews were conducted with 635 persons (241 men and 394 women). Depression and anxiety were assessed using the Finnish modified version of Beck's 13-item depression scale (RBDI), which was completed fully by 74% of the interviewees. Loneliness was assessed with a single four category item. In the second phase of the study in 1996, interviews were conducted with 410 persons, of whom 94% filled the RBDI questionnaire. In the third phase in 2004, the number of interviewees was 220 and the response rate 82%. There were no significant changes in the number of people with depressive symptomatology and anxiety, except in 1996 when the proportion of men with mild and moderate depression almost doubled. The number of men and women who felt lonely increased significantly during the 16-year follow-up. People who said they were lonely also had more depression and anxiety than others. People who had grown up in warm and safe environment were the most balanced mentally. The presence or absence of warmth and safety in the formative environment is reflected in mental well-being even at a very old age.  相似文献   
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