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The aim of our study was to investigate gene variants in the long-term outcome of mood disorders. We retrospectively studied a sample of inpatients affected by recurrent and rapid cycling mood disorders. The serotonin transporter gene-linked functional polymorphic region (5-HTTLPR) and the A218C tryptophan hydroxylase (TPH) gene variant were determined using a PCR-based technique. For 5-HTTLPR polymorphism we genotyped 435 inpatients affected by major depressive (n=153), bipolar (n=213) and rapid cycling (n=69) mood disorders and 456 controls; for TPH we genotyped 399 inpatients (MD, n=132; BP, n=203; rapid cycling n=64) and 259 controls. Random Regression Model analysis was used to investigate the longitudinal time course of the illness. 5-HTTLPR and TPH polymorphisms were not associated with mood disorders time course. However we observed an excess of 5-HTTLPR*long alleles among rapid cycling subjects compared to both controls (P=0.018) and remitting mood disorders (P=0.006). TPH frequencies did not differ between mood disorders subtypes. Our results suggest that 5-HTTLPR variants may confer a susceptibility toward rapid cycling mood disorders.  相似文献   
94.
Tryptophan hydroxylase gene and major psychoses   总被引:8,自引:0,他引:8  
Disturbances of the serotoninergic neurotransmitter system have been implicated in the pathogenesis of mood disorders. The tryptophan hydroxylase (TPH) gene, which codes for the rate-limiting enzyme of serotonin biosynthesis, has been recently reported to be associated with bipolar disorder. In this study, we investigated TPH A218C gene variants in a sample of subjects affected by major psychoses. One thousand four hundred and twenty-four inpatients affected by bipolar (n=627), major depressive (n=511), schizophrenic (n=210), delusional (n=48) disorder and psychotic disorder not otherwise specified (n=27) (DSM-IV) were included; all patients and 380 controls were typed for the TPH variants using PCR techniques. A sub-sample of 963 patients was assessed using the Operational Criteria for Psychotic Illness (OPCRIT). TPH variants were not associated with major psychoses, but a trend was observed toward an excess of TPH*A/A in bipolar disorder. The analysis of symptomatology factors did not show any significant difference either; however, a trend was observed for males with the TPH*A genotype to have lower depressive symptoms compared with TPH*C subjects. Possible stratification factors such as current age and age of onset did not affect the observed results. TPH A218C variants are not, therefore, a major liability factor for the symptoms of major psychoses to have in the present sample. TPH*A containing variants may be a protective factor for depressive symptoms among male subjects with mood disorders or for a subtype of mood disorders characterized by a mainly manic form of symptomatology.  相似文献   
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BACKGROUND: Being the rate-limiting enzyme in the biosynthesis of serotonin, the tryptophan hydroxylase gene (TPH) has been considered a possible candidate gene in bipolar and unipolar affective disorders (BPAD and UPAD). Several studies have investigated the possible role of TPH polymorphisms in affective disorders and suicidal behavior. METHODS: The TPH A218C polymorphism has been investigated in 927 patients (527 BPAD and 400 UPAD) and their matched healthy control subjects collected within the European Collaborative Project on Affective Disorders. RESULTS: No difference of genotype distribution or allele distribution was found in BPAD or UPAD. No statistically significant difference was observed for allele frequency and genotypes counts. In a genotype per genotype analysis in UPAD patients with a personal history of suicide attempt, the frequency of the C-C genotype (homozygosity for the short allele) was lower in UPAD patients (24%) than in control subjects (43%) (chi(2) = 4.67, p =.03). There was no difference in allele or genotype frequency between patients presenting violent suicidal behavior (n = 48) and their matched control subjects. CONCLUSIONS: We failed to detect an association between the A218C polymorphism of the TPH gene and BPAD and UPAD in a large European sample. Homozygosity for the short allele is significantly less frequent in a subgroup of UPAD patients with a history of suicide attempt than in control subjects.  相似文献   
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Ga-68-labeled radiotracers, particularly used for the detection of neuroendocrine tumors by means of Ga-68-DOTA-TATE or -DOTA-TOC or for the diagnosis of prostate cancer by means of Ga-68-labeled antigens (Ga 68-PSMA), become increasingly important. In addition to the high sensitivity and specificity of these radiopharmaceuticals, the short-lived radionuclide Ga-68 offers almost ideal nuclear characteristics for use in PET. Ga-68 is obtained from a germanium-gallium-generator system, so that the availability of Ga-68-labeled radiotracers is independent of an on-site-cyclotron regardless of the short half-life of Ga-68 of about 68 minutes. Regarding the disposal of the radioactively contaminated waste from the preparation of the radiopharmaceutical, the eluted Ga-68 has to be considered to be additionally contaminated with its parent nuclide Ge-68. Due to this production-related impurity in combination with the short half-life of Ga-68, the radioactive waste has to be considered to be contaminated with Ge-68 and Ga-68 in radioactive equilibrium (hereafter referred to as Ge-68+). As there are no clearance levels for Ge-68+ given in the German Radiation Protection Ordinance, this work presents a method to calculate the missing value basing on a recommendation of the German Radiation Protection Commission in combination with simple geometric models of practical radiation protection. Regarding the relevant exposure scenarios, a limit value for the unrestricted clearance of Ge-68+ of 0.4 Bq/g was determined.  相似文献   
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PURPOSE Adjuvant radiotherapy in the treatment of rectal cancer has been shown to increase long-term morbidity causing severe anorectal dysfunction with physiologic changes whose interaction remains poorly understood. This study examines long-term anorectal morbidity from adjuvant postoperative radiotherapy.METHODS In a prospective study, patients with Dukes B or C rectal carcinoma were randomized to postoperative radiotherapy or no adjuvant treatment after anterior resection. The long-term effect of radiotherapy on anorectal function in a subset of surviving patients was assessed from a questionnaire on subjective symptoms and from physiology laboratory evaluation and flexible sigmoidoscopy.RESULTS Twelve of 15 patients (80 percent) treated with radiotherapy had increased bowel frequency compared with 3 of the 13 patients (23 percent) who did not have radiation therapy (P = 0.003). The former group had loose or liquid stool more often (60 vs. 23 percent, P = 0.05), had fecal incontinence more often (60 vs. 8 percent, P = 0.004), and wore pad more often (47 vs. 0 percent, P = 0.004). They also experienced fecal urgency and were unable to differentiate stool from gas more often. Endoscopy revealed a pale and atrophied mucosa and telangiectasias in the irradiated patients. Anorectal physiology showed a reduced rectal capacity (146 vs. 215 ml, P = 0.03) and maximum squeeze pressure (59 vs. 93 cm H2O, P = 0.003) in the radiotherapy group. Impedance planimetry demonstrated a reduced rectal distensibility in these patients (P < 0.0001).CONCLUSIONS Adjuvant postoperative radiotherapy after anterior resection causes severe long-term anorectal dysfunction, which is mainly the result of a weakened, less sensitive anal sphincter and an undistensible rectum with reduced capacity.  相似文献   
100.
Summary. Mixed cryoglobulinaemia, when not secondary to other well-defined immunological disorders, is commonly associated with hepatitis C virus (HCV) infection. However, a minority of cases lack evidence of HCV infection and are, therefore, defined as 'true essential' mixed cryoglobulinaemias. We thoroughly investigated three such patients to determine the aetiology of this disorder.
Antibodies to HCV (anti-HCV) and HCV RNA, detected by sensitive enzyme-linked immunosorbent and polymerase chain reaction assays in serum and in concentrated cryoglobulins, were repeatedly negative in the three patients. Despite the lack of evidence for HCV infection, two of them were still treated with interferon α -2a assuming unrecognized viral infection. Both patients demonstrated excellent clinical and laboratory responses, but cryoglobulinaemia relapsed after the withdrawal of therapy. At the time of relapse, HCV RNA genomic sequences were detected for the first time in the cryoprecipitates of both patients. In the third case, HCV RNA was demonstrated for the first time during a flare of cryoglobulinaemia coincident with varicella infection. In all three patients anti-HCV antibodies remained negative throughout follow-up.
We conclude that some apparently 'essential' forms of mixed cryoglobulinaemia can be caused by occult HCV infection. Interferon therapy can be taken into consideration in such HCV-negative cases.  相似文献   
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