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1.
Aggressive behavior linked to corticotropin-reactive autoantibodies.   总被引:3,自引:0,他引:3  
BACKGROUND: Altered stress response is characteristic for subjects with abnormal aggressive and antisocial behavior, but the underlying biological mechanisms are unclear. We hypothesized that autoantibodies (autoAbs) directed against several stress-related neurohormones may exist in aggressive subjects. METHODS: Using enzyme-linked immunosorbent assay, we studied whether autoAbs directed against corticotropin (ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), oxytocin, and vasopressin are present in serum of male subjects with conduct disorder and prisoners with history of violence. Healthy blood donors served as control subjects. RESULTS: Both conduct disorder and prisoners groups displayed strongly increased levels of ACTH-reactive immunoglobulin G (IgG) and immunoglobulin M (IgM) autoAbs compared with control subjects. Levels of oxytocin-reactive IgM autoAbs were slightly increased in both groups of aggressive subjects, whereas levels of vasopressin-reactive IgG and IgM autoAbs were lower only in conduct disorder. No differences in the levels of alpha-MSH-reactive autoAbs were found between aggressive and control subjects. CONCLUSIONS: High levels of ACTH-reactive autoAbs as well as altered levels of oxytocin- and vasopressin-reactive autoAbs found in aggressive subjects may interfere with the neuroendocrine mechanisms of stress and motivated behavior. Our data suggest a new biological mechanism of human aggressive behavior that involves autoAbs directed against several stress-related neurohormones.  相似文献   
2.
The biodistribution of two recently developed tumour markers, trimethylated (CP(Me)3) and trimethoxylated (CP(OMe)3) carotenoporphyrin, was investigated by means of laser-induced fluorescence (LIF) after i.v. injection into 38 tumour-bearing (MS-2 fibrosarcoma) female Balb/c mice. At 3, 24, 48 or 96 h after administration, the carotenoporphyrin fluorescence was measured in tumoral and peritumoral tissue, as well as in the abdominal, thoracic and cranial cavities. The fluorescence was induced by a nitrogen laser-pumped dye laser, emitting light at 425 nm, and analysed by a polychromator equipped with an image-intensified CCD camera. The fluorescence was evaluated at 490, 655 and 720 nm: the second and third wavelengths represent the carotenoporphyrin (CP)-related peaks, whereas the first one is close to the peak of the tissue autofluorescence. The tumour and the liver were the two tissue types showing the strongest carotenoporphyrin-related fluorescence, whereas the cerebral cortex and muscle consistently exhibited weak substance-related fluorescence. In most tissue types, the fluorescence intensities decreased over time. A few exceptions were observed, notably the liver, in which the intensity remained remarkably constant over the time period investigated.  相似文献   
3.
Irradiation of a cytosolic fraction from vascular smooth muscle in the presence of [3H]felodipine resulted in the labelling of a protein with an apparent molecular weight of 62 kDa. The labelling was seen on UV-irradiation at 360 nm, but not at 254, 278 or at wavelengths above 410 nm. The photolabelling was enhanced in the absence of oxygen. In cytosolic fractions prepared from porcine liver, cardiac and skeletal muscle no photoaffinity labelling of proteins between 90 and 45 kDa could be demonstrated. The results suggest that felodipine is a photoaffinity ligand and that felodipine binds to a soluble protein present in vascular smooth muscle but not in the other tissues tested.  相似文献   
4.
The sequence of structural changes involved in postnatal photoreceptor differentiation, maturation and early degeneration was studied in young Abyssinian cats and kittens with hereditary rod-cone degeneration and compared to maturation in normal controls. In affected cats the earliest change seen was disorientation of outer segment discs in the majority of the rods, while other rods appeared to develop and mature normally. Such disorientation of discs (at oblique angles or parallel to the longitudinal axis of the outer segment, or whorls of discs) is considered as 'immaturity', since controls also showed a substantial number of disoriented rod outer segment discs at this young age. At postnatal day 35 the difference between affected animals and controls was marked with a high frequency of immature appearing rod outer segment discs in affected animals, while all rod outer segment discs were adult-like and arranged in an orderly manner in controls. Cones seemed unaffected at this age. More severe changes in affected rod outer segments in the form of disintegration of discs (vacuolization and clumping of disc material, or formation of debris), which we consider to represent degeneration, were first observed at the time when retinal maturation normally occurs in the cat, i.e. 150 days postnatally. Subsequently a drop-out of rods was seen, primarily of rods with disoriented and disintegrated outer segment discs, followed by a slow, progressive degeneration of rods that had developed and matured normally. Cones appeared normal during the time of retinal development and maturation and it was not until the age of 2-3 years (Narfstr?m and Nilsson, 1986, Incest. Ophthalmol, Vis. Sci. 27, 1569-76) that degenerative changes were seen also in cones.  相似文献   
5.
Suramin was used to analyze the growth-effects of blockade of iron uptake on two established human cell lines, U-937 (monocytoid) and K-562 (erythroleukemic). Suramin suppressed cell surface transferrin (Tf) binding and uptake of iron via inhibition of receptor-mediated endocytosis (RME). As a result, both lines accumulated in the S-phase. DNA synthesis and cell division were inhibited in the suramin-treated U-937, but not in K-562. Iron, supplied by a route alternative to Tf-to suramin-suppressed U-937 cells, reinitiated DNA synthesis and cell division, although at a lower level than in control cells. Multiple effects on iron-dependent enzymes and an inhibition of binding of undefined growth factors necessary for the transition through the cell cycle are suggested to be mechanisms by which suramin affects the U-937 cells. The results imply that clinically observed side effects of suramin may be caused by interference with cellular iron metabolism.  相似文献   
6.
A review of hip radiographs of patients with severe hemophilia showed Legg-Calvé-Perthes disease in four of 63 patients examined before the era of specific treatment. In another series of 44 patients receiving prophylactic treatment, there was no evidence of Legg-Calvé-Perthes disease. A case report of a boy with severe hemophilia with hip joint bleeding that caused joint capsule distention and greatly increased intracapsular pressure is presented. Based on our findings, and previously published results, we suggest that Legg-Calvé-Perthes disease in hemophilia is caused by increased intracapsular pressure secondary to hemarthrosis.  相似文献   
7.
Blood cell trauma and postoperative bleeding were studied in 96 patients following coronary artery bypass grafting, with bubble oxygenator used in 47 cases and membrane oxygenator in 49. The haemocompatibility of membrane oxygenators was superior to that of the bubble type, as reflected by less haemolysis, better preservation of platelet function, less release of betathromboglobulin and less degranulation of neutrophil granulocytes. Coronary suction contributed to haemolysis, but did not affect platelet or granulocyte function. Fibrinolysis, postoperative blood loss and need for blood transfusion did not differ between the bubble and membrane oxygenator groups.  相似文献   
8.
We studied 362 fractures of the femur that had occurred during the years 1950-57 and 1973-83, and 849 fractures of the tibia that occurred during the the years 1950-55 and 1980-83. There was an increase in age-specific incidence over aged 60 years. The risk of low-energy femoral shaft fractures also had increased in elderly women. Both fracture types shifted their age- and sex-specific incidence in the direction of a fragility pattern. There was no increase in the incidence of tibial shaft fractures. Fracture type, site, and degree of displacement of the tibial fractures remained unchanged during the 30 years, i.e, they were predominantly distal, longitudinal fractures with moderate displacement.  相似文献   
9.
Cancer incidence of workers in the Swedish petroleum industry.   总被引:3,自引:2,他引:1       下载免费PDF全文
OBJECTIVES: To estimate the risk of cancer due to occupational exposure to petroleum products in the Swedish transport and refinery industries. METHODS: In a retrospective cohort study the cancer incidence in 4128 men and 191 women, who had worked for at least one year in the petroleum industry, was compared with the incidence in the general population. The job titles and employment times for each person were found in personal files in the industries. The men had on average worked in jobs exposed to petroleum for 11.6 years at the end of the observation period. The cases of cancer were identified by record linkage with the Swedish cancer register. RESULTS: In total there were 146 cases of cancer v 157.6 expected (standardised mortality ratio (SMR) 0.93 90% confidence interval (90% CI) 0.80 to 1.1). Operators at refineries had an increased risk of leukaemia (6 cases v 1.7 expected, 90% CI of relative risk (RR) 1.5 to 7.0). Five of the six cases had started to work at the refineries in the 1950s or later. No other significantly increased risk of cancer was found. Distribution workers had a decreased incidence of lung cancer (no cases, 90% CI of RR 0 to 0.4). CONCLUSIONS: Operators at Swedish refineries had an increased risk of leukaemia. A possible cause is exposure to benzene. There was no increased risk of leukaemia in distribution workers. Distribution workers had a decreased risk of lung cancer.  相似文献   
10.
Digital movment analysis (DMA) is a new instrumental approach to assessing oral tardive dyskinesia (TD) by means of digital image processing of a video signal, tracking five paper dots placed around the patient's mouth. A total of 40 schizophrenic patients, 30 with and 10 without TD, were examined twice (with a 3-month interval) with this new device. The patients were further examined with two TD rating scales: the St. Hans Rating Scale for extrapyramidal syndromes (SHRS) and the Abnormal Involuntary Movement Scale (AIMS).The schizophrenic patients accepted the instrumental assessment without any anxiety or resistance. The internal relibility of the apparatus was high, with correlation coefficients of 0.80–0.99. The DMA TD values correlated with the SHRS and AIMS scores with correlation coefficients of 0.48–0.73 indicating an acceptable, although not strong, concurrent validity. Fluctuations occurred from the first to the second examination independent of medication. For these fluctuations no correlation was found between DMA values and rating scores. Finally, the DMA device was able to detect perioral tremor as a sign of parkinsonism.It has been concluded that DMA is a useful supplement to classical TD rating, although further validity evaluation is warranted.  相似文献   
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