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INTRODUCTION: A consensus has not yet been reached regarding the indications for orthotopic heart transplantation (OHT) in elderly patients or the age limit contraindicating the procedure. The objective of this study was to assess OHT outcomes to determine whether elderly patients benefit from the procedure. METHODS: From February 1993 to February 2003, 178 OHTs were performed on recipients of mean age 47.4 +/- 15 years (range, 4 to 74) including 80.3% men. The population was divided into two groups: group A included patients >/= 60 years, and group B those younger than that age. Survival was analyzed for the overall population and for both age groups during a 10-year follow-up period. RESULTS: Group A included 36 patients (20.8%) and group B 142 patients (79.2%). Mean age was 63.7 +/- 2.9 years (60 to 74) in A, and 43 +/- 13.9 years (4 to 59) in B. In-hospital mortality was significantly higher among group A (n = 11, 31.4%) compared to B (n = 17, 12.1%, P =.008). Survival at 1, 5, and 10 years was 61.5% +/- 8%, 58.1% +/- 8.3%, and 49.8% +/- 10.5% group A; and 84.2% +/- 3%, 73.7% +/- 4.1%, and 69.9% +/- 4.7 for group B. Elderly patients showed a lower survival rate (49.8%) compared with the younger group (69.9%) at 10-year follow-up (P =.007). Conditional survival at 9 years failed to show significant differences (A 72.2% vs B 79.6%, P =.4). CONCLUSION: In our population, elderly recipients showed a higher in-hospital mortality. However, when the first post-OHT year was excluded, we found similar survival rates for both age groups.  相似文献   
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The aim of present study is to evaluate whether traffic policemen exposed to urban pollutants and possible psycho-social stressors could be at risk of alterations on plasma insulin-like growth factor (IGF-1) levels compared to a control group. Out of a population of 395 Municipal Police employees, the subjects with principal confounding factors (cigarette smoking habits, drinking habits, oral contraceptives being taken, use of paints, solvents and pesticides) were excluded from the study. The remaining traffic policemen were matched with those not exposed by sex, age and length of service; 49 traffic policemen (22 men and 27 women) with outdoor activity exposed to urban pollutants and 49 not exposed subjects (22 men and 27 women) with indoor activity were included in the study. The plasma levels of IGF-1 resulted significantly higher in the male and female traffic policemen compared with control subjects (respectively P<0.001; P<0.001). The authors hypothesise that occupational exposure to chemical stressors, that may interact with possible psycho-social stressors, could cause an alteration on IGF-1 levels in traffic policemen.  相似文献   
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A series of N-(1,2,3,4-tetrahydronaphthalen-1-yl)-4-aryl-1-piperazinealkylamides was prepared and their affinity for serotonin (5-hydroxytryptamine, 5-HT) 5-HT7, 5-HT(1A), and 5-HT(2A) receptors was measured by in vitro binding assays. In relation to 5-HT7 receptor affinity, receptor binding studies indicated that (i) the optimal alkyl chain length was five methylenes, (ii) an unsubstituted 1,2,3,4-tetrahydronaphthalenyl nucleus was preferred, and (iii) the substitution pattern of the aryl ring linked to the piperazine ring played a crucial role. Several compound with high affinity for 5-HT7 receptors were identified. Among them, 4-(2-methoxyphenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazinehexanamide (28), 4-(2-acetylphenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazinehexanamide (34), 4-(2-methylthiophenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazinehexanamide (44), 4-(2-hydroxyphenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazinehexanamide (46), and 4-(2-methylphenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazinehexanamide (49) were assayed for the 5-HT7 receptor-mediated relaxation of substance P-induced guinea pig ileum contraction. Compounds 28, 44, and 49 behaved as full agonists and compound 34 as a partial agonist, whereas derivative 46 acted as an antagonist. Among the compounds presented here, it emerged that 44 was identified as a potent 5-HT7 receptor agonist (Ki = 0.22 nM, EC50 = 2.56 microM), endowed with selectivity over 5-HT(1A) and 5-HT(2A) receptors (200-fold and >1000-fold, respectively).  相似文献   
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OBJECTIVES: We retrospectively evaluated the relevance of thymidylate synthase (TS) expression in normal colonic mucosa as a predictive factor of toxicity in colorectal cancer patients receiving adjuvant fluorouracil (5-FU)-based chemotherapy. METHODS: TS expression was immunohistochemically assessed on normal colonic mucosa from 50 patients with colorectal cancer Dukes' stages B (15 patients) and C (35 patients) treated with 5-FU-based adjuvant chemotherapy. RESULTS: The incidence of grade 2-3 diarrhea and stomatitis (according to WHO) was demonstrated to be significantly higher in patients with low nuclear TS expression in normal mucosa than in those with high TS expression (p < 0.0001). Moreover, patients with low TS expression in normal colonic mucosa developed weight loss and worsening of the performance status (according to ECOG score) more commonly than patients with high TS expression (p = 0.005 and p = 0.02, respectively). Furthermore, low TS expression in normal colonic mucosa significantly correlated with a higher rate of a delay of chemotherapy courses, dose reduction and treatment discontinuation. CONCLUSIONS: Immunohistochemical TS expression in normal colonic mucosa may represent an important predictive parameter for identifying a subset of patients with a high risk of developing severe 5-FU-related toxicities.  相似文献   
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Activin-A is a growth factor involved in cell growth and differentiation, neuronal survival, early embryonic development and erythropoiesis. Hypoxemia is a specific trigger for increasing activin-A in fetal lamb circulation. We tested the hypothesis that fetal hypoxia induces activin-A secretion in preterm newborn infants. Fifty newborn infants with gestational ages ranging from 26 to 36 wk were enrolled in a prospective study performed at the Pediatrics, Obstetrics and Reproductive Medicine Department, University of Siena, Italy. Heparinized blood samples were obtained from the umbilical vein after cord clamping, immediately after delivery. Activin A, hypoxanthine (Hx), xanthine (Xa) plasma levels and absolute nucleated red blood cell (NRBC) count were measured. Activin-A levels (p < 0.0001) and NRBC (p < 0.0001) were significantly higher in hypoxic than in non hypoxic preterm newborns. Cord activin A levels were significantly related with Hx (taua=0.64, taub=0.64, p < 0.0001) and Xa (taua=0.56, taub=0.57, p < 0.0001) levels, NRBC ((taua=-0.45, taub=-0.46, p < 0.0001) count; pH (taua=-0.47, taub=-0.48, p < 0.0001) and base deficit (taua=-0.36, taub=0.-0.36, p = 0.0002). Preterm newborns with signs of perinatal hypoxia at birth have increased activin-A levels, suggesting that activin-A may reflect indirectly intrauterine hypoxia.  相似文献   
109.
We studied the children of mothers who were confined to bed during pregnancy for more than 15 consecutive days (mean 3.69 months) in the years 1986-1990 (bed rest offspring; BRO). We studied 86 children: 43 BRO and 43 control children. Data were obtained by means of a 20-item questionnaire filled in by the mothers. The BRO group differed from the control group in incidence of allergies (p = 0.005), motion sickness (p = 0.03), and need to be rocked to fall asleep (p = 0.01). More BRO born at term than controls played musical instruments later in life. Two possible explanations for more allergies among the BRO group are the use of beta-stimulating drugs against premature delivery and the effects of prolonged stress on the developing immune system. Understimulation of the developing vestibular system during gestation may affect some aspects of its development and may explain the higher incidence of motion sickness and need for vigorous rocking in BRO.  相似文献   
110.
The objective of the present study was to gain a better understanding of the role played by scarce leptin production in the deranged sexual development observed in patients with thalassemia. We studied 101 patients at different stages of puberty. Patients of both sexes were divided into three groups according to Tanner stages: T1-2 (20 males and 12 females), T3-4 (9 males and 4 females) and T5 (48 males and 8 females). Serum levels of leptin, ferritin, testosterone and estradiol were assessed. Leptin levels were adjusted for body mass index (BMI) using reference ranges stratified on the basis of gender and pubertal development. Deviations from the mean reference values were evaluated by calculating the standard deviation scores. Mean leptin standard deviation scores were significantly lower than expected in pubertal stage T1-2 and T3-4 in males and T3-4 and T5 in females. The peak leptin level was delayed in boys (13 years). In girls, parallelism between leptin and BMI was present until age 7-10 years; thereafter, although BMI constantly increased, leptin levels fell dramatically. Mean ferritin levels were significantly higher in pubertal stage T1-2 among males and in T5 among females. These findings show that in thalassemia adipose tissue is unable to assure adequate leptin production just when the highest leptin secretion is required and suggest that this inappropriate leptin secretion may be a cofactor of the derangement in pubertal timing observed in patients with thalassemia.  相似文献   
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