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51.

Background

Serotonin plays an important role in treatment of depression. We evaluated the clinical correlates of plasma serotonin levels in depressed patients before and after treatment.

Methods

Study sample comprised of 40 patients diagnosed on ICD-10 diagnostic criteria, and an equal number of healthy matched controls. Subjects were evaluated on Beck''s Depression Inventory (BDI) and Suicide Ideation Scale (SIS), before and after the treatment. Blood samples were collected from all the cases and controls before starting the antidepressant medication with selective serotonin reuptake inhibitors (SSRI''s). Serum serotonin levels were measured before and after treatment.

Result

Significant differences in scores before and after the intervention on BDI, SIS and serotonin levels of cases and controls (p<.000) were noted. Correlation between the serum serotonin levels before and after the treatment, and between the rating scales did not reveal significant association (p > 0.05). Patients with suicidal intentions had lower levels of serotonin. The scores changed after intervention.

Conclusion

Treatment with SSRI''s had shown significant changes in clinical conditions. However these changes did not relate significantly with serum serotonin levels.Key Words: Serotonin, Depression, Selective serotonin reuptake inhibitors  相似文献   
52.
Medium‐chain acyl‐CoA dehydrogenase deficiency (MCADD) represents a potentially fatal fatty acid β‐oxidation disorder. Newborn screening (NBS) by tandem mass spectrometry (MS/MS) has been implemented worldwide, but is associated with unresolved questions regarding population heterogeneity, burden on healthy carriers, cut‐off policies, false‐positive and negative rates. In a retrospective case‐control study, 333 NBS samples showing borderline acylcarnitine patterns but not reaching recall criteria were genotyped for the two most common mutations (c.985A>G/c.199C>T) and compared with genotypes and acylcarnitines of 333 controls, 68 false‐positives, and 34 patients. c.985A>G was more frequently identified in the study group and false‐positives compared to controls (1:4.3/1:2.3 vs. 1:42), whereas c.199C>T was found more frequently only within the false‐positives (1:23). Biochemical criteria were devised to differentiate homozygous (c.985A>G), compound heterozygous (c.985A>G/c.199C>T), and heterozygous individuals. Four false‐negatives were identified because our initial algorithm required an elevation of octanoylcarnitine (C8) and three secondary markers in the initial and follow‐up sample. The new approach allowed a reduction of false‐positives (by defining high cut‐offs: 1.4 μmol/l for C8; 7 for C8/C12) and false‐negatives (by sequencing the ACADM gene of few suspicious samples). Our validation strategy is able to differentiate healthy carriers from patients doubling the positive predictive value (42→88%) and to target NBS to MCADD‐subsets with potentially higher risk of adverse outcome. It remains controversial, if NBS programs should aim at identifying all subsets of all diseases included. Because the natural course of milder variants cannot be assessed by observational studies, our strategy could serve as a general model for evaluation of MS/MS‐based NBS.  相似文献   
53.

Background  

Mandatory vaccination has contributed to the success of immunisation programmes but voluntary vaccination allows people to be responsible for their own health. There are benefits from both policies and the arguments between them remain subject to debate within and without the scientific community, both nationally and internationally. The aim of this study is to assess the opinions of those who actually work in the Vaccination Service.  相似文献   
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55.
Organic peroxides, widely used in the chemical and pharmaceutical industries, can act as skin tumor promoters and cause epidermal hyperplasia. They are also known to trigger free radical generation. The present study evaluated the effect of cumene hydroperoxide (Cum-OOH) on the induction of activator protein-1 (AP-1), which is linked to the expression of genes regulating cell proliferation, growth and transformation. Previously, we reported that topical exposure to Cum-OOH caused formation of free radicals and oxidative stress in the skin of vitamin E-deficient mice. The present study used JB6 P+ mouse epidermal cells and AP-1-luciferase reporter transgenic mice to identify whether exposure to Cum-OOH caused activation of AP-1, oxidative stress, depletion of antioxidants and tumor formation during two-stage carcinogenesis. In vitro studies found that exposure to Cum-OOH reduced the level of glutathione (GSH) in mouse epidermal cells (JB6 P+) and caused the induction of AP-1. Mice primed with dimethyl-benz[a]anthracene (DMBA) were topically exposed to Cum-OOH (82.6 micromol) or the positive control, 12-O-tetradecanoylphorbol-13-acetate (TPA, 17 nmol), twice weekly for 29 weeks. Activation of AP-1 in skin was detected as early as 2 weeks following Cum-OOH or TPA exposure. No AP-1 expression was found 19 weeks after initiation. Papilloma formation was observed in both the DMBA-TPA- and DMBA-Cum-OOH-exposed animals, whereas skin carcinomas were found only in the DMBA-Cum-OOH-treated mice. A greater accumulation of peroxidative products (thiobarbituric acid-reactive substances), inflammation and decreased levels of GSH and total antioxidant reserves were also observed in the skin of DMBA-Cum-OOH-exposed mice. These results suggest that Cum-OOH-induced carcinogenesis is accompanied by increased AP-1 activation and changes in antioxidant status.  相似文献   
56.
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58.
Fat and mineral metabolic balance studies were performed in 25 normal very low-birth-weight infants ( 1500 g at birth) fed either pooled pasteurized human milk supplemented with calcium, phosphorus and magnesium, or a preterm formula. Calcium, phosphorus and magnesium intake were similar in both groups and averaged 100mg/kg/day, 72 mg/kg/day and 8 mg/kg/day, respectively. Calcium and phosphorus retention was higher in the subjects fed fortified human milk than in those receiving a preterm formula (65±14 and 62±9mg/kg/day versus 55±12 and 47±7mg/kg/day respectively). The difference was only significant for phosphorus. Magnesium retention was similar in the two groups and averaged 3 mg/kg/day. Fat intake and absorption was significantly higher in the preterm formula fed group than in the one fed fortified human milk (5.5±0.4 g/kg/day and 88±4% versus 4.2±1 g/kg/day, 79±6% respectively). Assessment of the whole body bone mineral content by dual energy X-ray absorptiometry was performed at 3 and 6 months of age in another group of 25 low-birth-weight infants fed either fortified human milk or a preterm formula. Whole body bone mineral content (BMCt) was low (43.3±30.8 g of hydroxyapatite) at 3 months of age (theoretical term) compared to normal full-term newborns at birth. There was no significant influence of the diet. At 6 months of age, BMCt reached 168.6±36.6g, a value similar to that of full-term newborns, with no significant difference between the two regimen groups. The deficit in the 12 subjects who had a BMCt under 30 g at 3 months of age had been corrected at age 6 months. Premature babies fed a pooled pasteurized human milk enriched with calcium, phosphorus and magnesium favored a better retention of calcium and phosphorus. However, no significant influence of the two diets studied was observed on the gain in BMCt over the first 6 months of life.  相似文献   
59.
慢性疼痛综合征患者常应用非甾体抗炎药( non-steroidal anti-inflammatory drugs,NSAID).许多这类患者有潜在的高血压和冠状动脉疾病.临床试验和系统性分析显示,选择性环氧化酶2抑制剂增加心肌梗死的风险[J].该发现可能导致更普遍地应用非选择性NSAID作为治疗慢性疼痛综合征的替代手...  相似文献   
60.
Hasan  AA; Cines  DB; Ngaiza  JR; Jaffe  EA; Schmaier  AH 《Blood》1995,85(11):3134-3143
An important biologic function of high-molecular-weight kininogen (HK) is to deliver bradykinin (BK) to its cellular receptors. Internalization and degradation of HK may provide a mechanism by which endothelial cells modulate the production of BK and control its activities. Therefore, we investigated the binding and subsequent distribution of biotinylated-HK (biotin-HK) associated with human umbilical vein endothelial cells (HUVEC). HUVEC bound 3 to 4 times more HK and with greater avidity at 1 to 3 hours at 37 degrees C than at 4 degrees C (Bmax = 1.0 +/- 0.02 x 10(7) molecules/cell, kd = 7 +/- 3 nmol/L v Bmax = 2.6 +/- 0.2 x 10(6) molecules/cell, kd = 46 +/- 8 nmol/L). However, there was no evidence that the difference was caused by internalization of HK at the higher temperature. First, the same amount of biotin-HK was associated with nonpermeabilized and permeabilized HUVEC using buffers containing 20 to 50 mumol/L zinc ion in the absence or presence of 2 mmol/L calcium ion. Second, binding of biotin-HK to HUVEC was approximately 92% reversible at 1 hour when the cells were maintained at both 37 degrees C and 4 degrees C. Third, neither chloroquine nor primaquine altered the amount of biotin-HK bound to HUVEC. Fourth, biotin-HK bound to HUVEC was almost completely removed by pronase. Fifth, the nonpermeable dye, crystal violet, almost completely quenched the fluorescence signal emitted by HUVEC-associated fluorescein isothiocyanate (FITC) HK. Finally, the localization of HUVEC-bound FITC-HK was restricted to the membrane as shown by laser scanning confocal microscopy. The expression of HK binding sites had an absolute requirement for metabolic energy, but was not dependent on new protein synthesis. Membrane-bound HK contributed to the anticoagulant nature of endothelial cells by blocking human alpha-thrombin binding and its resultant induction of prostacyclin formation. These studies indicate that HK is not internalized by HUVEC, but remains primarily on cell surfaces to be accessible for BK liberation and to modulate the binding and actions of alpha-thrombin.  相似文献   
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