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131.
BACKGROUND/OBJECTIVE: The aim of our study was first to investigate if there exists an interaction between nitric oxide (NO) and prostaglandin (PG) generation in the estrogenized rat uterus challenged by lipopolysaccharide (LPS), and, secondly, which isoforms of nitric oxide synthase (NOS) and cyclooxygenase (COX) participate in this process. METHODS: To study the effect of LPS and to characterize the isoenzymes involved in the process, specific inhibitors of iNOS (aminoguanidine) and COX-II (meloxicam, nimesulide) and non-specific of COX (indomethacin) were injected intraperitoneally to determine their effect on NO and PG production, and on NOS and COX expression induced by LPS in estrogenized rat uterus. NO production was measured by arginine-citrulline conversion assay and PGE(2)/PGF(2alpha,)by radioconversion. Enzyme expression was evaluated by Western blot analysis. RESULTS: The present work shows that iNOS inhibitor, aminoguanidine, reduced NO and PGE(2)/PGF(2alpha) production induced by LPS injection. Aminoguanidine exerts its effect over the PG metabolism by inhibiting COX-II activity and expression. On the other hand, both indomethacin, a non-selective PG inhibitor, and meloxicam, a COX-II inhibitor, stimulated NO production and reduced PGE(2)/PGF(2alpha) generation. Indomethacin also reduced COX-II and iNOS expression. CONCLUSION: These results indicate that in the estrogenized rat uterus challenged with LPS, PG and NO interact affecting each other's metabolic pathways. The above findings indicate that the interaction between NOS and COX might be important in the regulation of physiopathologic events during pregnancy.  相似文献   
132.
Spa therapy is an ancient approach to degenerative diseases such as osteoarthritis, but until today this tradition has been predominantly empiric and intuitive and few studies have focused on the biological changes derived from this treatment. We assessed the clinical efficacy and variations in amino acid concentrations in serum samples from patients with knee osteoarthritis who underwent spa therapy and put forward an explanation of their role in clinical improvement. Thirty-one patients with knee osteoarthritis who underwent spa therapy underwent a clinical evaluation, and serum amino acid levels were assayed before and after a cycle of balneotherapy and mud-pack therapy. The thermal treatments were carried out in Sciacca. Analysis of the data showed a significant reduction in pain and improvement in joint motility. Serum concentrations of tryptophan, cysteine and citrulline were significantly higher than at baseline. No significant differences were observed in serum levels of the remaining free amino acids. The results of this study confirm the efficacy of spa therapy in the treatment of osteoarthritis. A possible role for changes in serum amino acid concentration is discussed.  相似文献   
133.
BACKGROUND: In the last 10 years an impressive increase in the frequency of food disorders (bulimia and anorexia) in teenagers has been recorded. Food disorders, present especially in girls, (part of more complex relational-familiar disorders) cause progressive repercussions on the general endocrine structure and in particular on the reproductive system of the subject. The most visible effect of this endocrine perturbation is the block of the ovarian function with secondary amenorrhoea and low levels of gonadotropins and estrogens due to the food disorder. In fact the qualitative and quantitative food deficit is responsible for the interruption of the normal hypothalamic and pituitary pulses regulating the correct monthly process of follicular growth. As in the physiological postmenopausal period, very low plasma levels of 17-b-estradiol (<30 pg/ml) can start the bone resorption with bone loss and/or osteoporosis related to the amount and the time of exposure to low levels of estrogens. Objectives: in our study we evaluate the influence of anorexia and amenorrhoea on bone mineral density. METHODS: We evaluate bone mineral density (BMD) with computerised bone mineralometry (MOC), a dual-energy-X-Ray (DEXA), in 18 women with anorexia nervosa and weight loss, 9-12 months amenorrhoea and with low plasma levels of 17-b-estradiol. The BMD was measured at the lumbar spine (L2-L4) and on total body in all subjects enrolled for this study. RESULTS: All the patients showed a decrease on the lumbar BMD with bone loss (49%) or osteoporosis (51%). On the other side the values of total body BMD were around the normal levels (86%) or showed bone loss (14%). CONCLUSIONS: Our data support the hypothesis that lower estrogenic levels associated with anorexia nervosa have an impact on BMD, especially at lumbar level, with early incidence for quantitative and qualitative lower food intake.  相似文献   
134.
Down syndrome and cell-free fetal DNA in archived maternal serum   总被引:6,自引:0,他引:6  
OBJECTIVE: Increased levels of cell-free fetal DNA (f-DNA) in the maternal circulation are a potential noninvasive marker for fetal Down syndrome. Our objectives were to (1) determine whether f-DNA could be quantified by using archived serum and amniotic fluid, (2) examine whether serum f-DNA levels are elevated in Down syndrome pregnancies in a case-control series matched for gestational age and duration of sample storage, and (3) determine whether f-DNA levels are elevated in the amniotic fluid of Down syndrome fetuses. STUDY DESIGN: Eleven serum and six amniotic fluid samples previously collected and stored at -20 degrees C from gravid women carrying a 47,XY,+21 fetus were each paired with five matched control samples of identical specimen type from gravid women carrying a presumed euploid male fetus. f-DNA concentration was quantified blindly by real-time polymerase chain reaction amplification for a Y-chromosome sequence. Matched rank-sum analysis and analysis of variance were used for analysis. RESULTS: The mean observed rank of 5.0 in the Down syndrome group was significantly higher than expected (P 相似文献   
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138.
Serum allopregnanolone in women with postpartum "blues"   总被引:3,自引:0,他引:3  
OBJECTIVE: To relate serum allopregnanolone and progesterone levels postpartum to maternity "blues." METHODS: Forty primiparous, healthy, married women (24-39 years of age; at least 13 years of education) who delivered healthy neonates in the Department of Obstetrics at the University of Pavia entered the present study. Blood samples were drawn at 8:30 AM on postpartum day 3 for measurements of serum allopregnanolone, progesterone, cortisol, prolactin, and estradiol. On the same day, every woman was interviewed using the Hamilton Rating Scale for Depression for psychometric testing and completed a self-administered version of the Stein Questionnaire for symptoms of the "blues." RESULTS: Eighteen of 40 women (45%) experienced maternity "blues" (12 who delivered vaginally and six who delivered by cesarean). Serum allopregnanolone levels were significantly lower in those women experiencing postpartum "blues" with respect to euthymic women (1.1 +/- 0.4 versus 2.3 +/- 1.0 nmol/L; P <.001), whereas progesterone levels did not differ significantly (11.6 +/- 5.6 versus 19.1 +/- 15.6 nmol/L; P >.058). Allopregnanolone and progesterone levels correlated significantly in euthymic women (r =.648; P =.001) but not in those with postpartum "blues" (r =.317; P =.199). There was a significant negative correlation between the Hamilton score and levels of serum allopregnanolone (r = -.62; P =.001) and progesterone (r = -.36; P =.024). CONCLUSION: Serum allopregnanolone levels were detectable postpartum and were significantly decreased in women with maternity "blues."  相似文献   
139.
OBJECTIVE: To describe the age-specific distribution of typhoid fever including the degree of Salmonella typhi bacteremia among patients evaluated at a large private diagnostic center in Bangladesh, a highly endemic area. METHODS: We conducted a prospective-, passive- and laboratory-based study to identify patients with S. typhi bacteremia. Subjects (n = 4,650) from whom blood cultures were obtained during 16-month period were enrolled from private clinics and hospitals throughout Dhaka. Isolation and quantification of S. typhi from blood cultures were performed by the lysis direct plating/ centrifugation method. RESULTS: Bacterial pathogens were recovered from blood of 538 of 4,650 patients (11.6%) evaluated. S. typhi was the single most common pathogen recovered, comprising nearly three-fourths of isolates (72.7%; 391 of 538). Isolation rate of S. typhi was highest in monsoon and summer seasons and lowest in winter months. The majority (54.5%; 213 of 391) of S. typhi isolates were from children who were younger than 5 years, and 27% (105 of 391) were from children in the first 2 years of life. The isolation rate was highest (17.4%, 68 of 486) in the second year of life. The number of bacteria in blood on the basis of colony-forming units per ml of blood by age group was inversely related to age. CONCLUSIONS: Detection of S. typhi bacteremia in young children in Dhaka, Bangladesh, was considerably higher than previously appreciated, with a peak detection rate in children < or =2 years of age, indicating the need to reassess the age-specific burden of typhoid fever in the community on a regional basis. Contrary to current recommendations this study suggests that development of new vaccines should target infants and young children.  相似文献   
140.
A 20-month-old girl successfully underwent repair of pulmonary artery sling through a median sternotomy by division of the left pulmonary artery and its reimplantation into the main pulmonary artery without cardiopulmonary bypass or tracheal reconstruction. The patient is doing well on 18 months follow-up with unobstructed pulmonary blood flow and dramatic reduction of tracheal stenosis. Simple repair of pulmonary artery sling is feasible with good results in selected cases without tracheomalacia.  相似文献   
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