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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.
In primary visual cortex of hooded rats, pyramidal cells in layer V may be classified as long, medium, or short, on the basis of the layer in which the apical dendrite terminates. The present study determines which of these types of pyramidal cells project to the superior colliculus. Two different strategies were used to label corticotectal cells with horseradish peroxidase (HRP). In the first set of experiments, a large number of corticotectal cells were labeled by retrograde transport following injection of HRP into the superior colliculus. In the second set of experiments, single unit recording was used to identify corticotectal cells physiologically by antidromic activation from the superior colliculus. These cells were then impaled and labeled by intracellular iontophoresis of HRP. The results from both techniques suggest that only long pyramidal cells send an axon to the superior colliculus. These cells are distinguished by an apical dendrite that extends into layer I. We conclude that in hooded rats corticotectal cells in primary visual cortex are the long pyramids in layer V.  相似文献   
3.
Antigenicity of low molecular weight surfactant species.   总被引:2,自引:0,他引:2       下载免费PDF全文
The authors tested the antigenicity of human lung surfactant isolated from amniotic fluid. Mice and rabbits were immunized. Rabbit polyclonal antisera to these surfactant preparations were absorbed with normal human plasma proteins. Polyclonal antisera reacted with both high molecular weight (35 kd) surfactant apoprotein and to lower molecular weight species, both 18 kd and 9 kd. Mice were used to generate monoclonal antibodies to surfactant. Enzyme-linked immunosorbant assay was used to identify five monoclonal antibodies that reacted with surfactant. By Western blot analysis, all of these recognized a low molecular weight surfactant species (9 kd) that could be either SP-B or SP-C. One reacted with a 37 kd protein in the surfactant preparation, consistent with SP-A. One monoclonal antibody also recognized a higher molecular weight species (44 kd) of unknown origin. The ability of antisera and monoclonal antibodies to inhibit the functional activity of surfactant was assayed using a pulsating bubble surfactometer. Rabbit polyclonal antisera inhibited initial surface adsorption to equilibrium surface tension and increased the minimum surface tension after 1 and 5 minutes of initiation of pulsations. This inhibitory activity of the antisera was noted in divalent F(ab')2 fragments. Monovalent F(ab) fragments and control normal rabbit sera did not inhibit surfactant function in this assay. Of the anti-surfactant monoclonal antibodies that reacted with surfactant by ELISA and Western blot, three inhibited its capacity to lower surface tension on the pulsating bubble apparatus. The other two monoclonal antibodies showed no functional inhibitory activity. It is concluded that both the 35 kd SP-A and the 9 kd proteins of human surfactant are highly immunogenic and partially crossreactive. Resulting antibodies could alter the ability of surfactant to perform its physiologic function, ie, to lower surface tension.  相似文献   
4.
In an ultrastructural study of 37 cases of bronchioloalveolar cell carcinoma (BAC), we identified seven cases (19%) in which Langerhans cells (LC) were closely associated with tumor cells. Serum precipitating antibodies against Aspergillus species and/or thermophilic actinomyces were present in five BAC patients whose tumors contained LC and in six patients whose tumors lacked LC. In a simultaneous study we identified marked atypical bronchiolar and alveolar lining cell hypertrophy and hyperplasma in pulmonary eosinophilic granuloma (PEG). Our data plus current information suggesting that PEG is a form of hypersensitivity pneumonitis support our hypothesis that those cases of BAC in which LC are present may arise in localized or diffuse pulmonary scars caused by PEG.  相似文献   
5.
Prophylactic treatment of very premature infants with human surfactant   总被引:5,自引:0,他引:5  
We undertook a randomized, controlled trial to determine whether human surfactant administered endotracheally at birth to very premature infants (gestational age, 24 to 29 weeks) would prevent the respiratory distress syndrome or reduce its severity. Thirty-one treated infants (birth weight, 938 +/- 286 g) were compared in a blinded fashion with 29 control infants (birth weight, 964 +/- 174 g). The lecithin/sphingomyelin ratio was less than 2 in all infants, and phosphatidylglycerol was not present in amniotic fluid or tracheal fluids at birth, indicating a deficiency of surfactant in the lungs. The principal dependent variables were neonatal death, the incidence of bronchopulmonary dysplasia, and the infant's requirement for respiratory support (and its complications). The surfactant-treated group had significantly fewer deaths than the control group (16 percent vs. 52 percent, P less than 0.001), fewer cases of bronchopulmonary dysplasia (16 percent vs. 31 percent), and significantly fewer cases of pulmonary interstitial emphysema (P less than 0.001) and pneumothorax (P less than 0.02). Prophylactic treatment with human surfactant also substantially reduced the period of neonatal intensive care. We conclude that treatment with human surfactant offers promise for improving the survival of very premature infants with a surfactant deficiency and for reducing the pulmonary sequelae of the respiratory distress syndrome.  相似文献   
6.
7.
The objective of this study was to compare semen quality (sperm density, progressive motility and spermia) between long-term childhood cancer survivors and a control group of males. The second objective was to correlate the semen analysis of the survivors with cancer treatment and endocrine status. The semen quality of 143 survivors (median age, 23.6 years) was compared to 200 men (median age, 27.9 years) who had not been diagnosed with cancer. The cancer-related risk factors and gonadotrophin levels were compared. Overall, 65% of the survivors had abnormal semen analysis compared to 26.5% of the controls (p < 0.0001). Survivors with nonaspermia had lower sperm density than the controls (p < 0.001). Other observed correlations were not significant. Survivors who were treated with alkylating agents were more likely to have abnormal semen analysis (p < 0.008). Follicle-stimulating hormone and luteinising hormone levels were significantly elevated (p < 0.0001) in survivors with abnormal semen analysis. The semen quality parameters, except for low sperm density, did not differ in survivors with nonaspermia compared to the controls. The risk factors included treatment with alkylating agents. Elevated gonadotrophin levels correlated with abnormal semen analysis. All cancer survivors should be made aware of the possibility of suffering from cancer treatment-related infertility.  相似文献   
8.
The new bis-naphthalimide antitumor agent (R,R)2,2-[1,2-ethanediylbis[imino(1-methyl-2.1-ethanediyl)]-bis {5-nitro-1H-benz[de]-isoquinoline-1,3-2H) dione} dimethanesulfonate (DMP 840) was evaluated against parental and multidrug-resistant human KB cell lines in vitro and against these lines growing as xenografts in immunedeprived mice. In vitro, KB8-5 cells were 50-fold resistant to vincristine but only 16-fold resistant to DMP 840 as measured by clonogenic survival. For in vivo evaluation, DMP 840 was given by i. v. injection daily for 9 days or for 5 days/week for 2 consecutive weeks [(dx5)2]. In contrast to the cross-resistance of KB cell lines in vitro, both KB3-1 and KB8-5 tumors were highly and equally sensitive to DMP 840; only KB3-1 xenografts demonstrated sensitivity to vincristine, which was consistent with the in vitro results. DMP 840 was also evaluated against a panel of human tumors comprising colon adenocarcinoma and rhabdomyosarcoma xenografts. Against eight lines of colon adenocarcinoma, DMP 840 caused a high frequency of partial and complete regressions in two lines and significant inhibition of growth in two lines. DMP 840 caused complete regressions in five of six lines of advanced rhabomyosarcomas, demonstrating a broad range of effective dose levels. The pattern of activity against this tumor panel was similar but not identical to that of two inhibitors of topoisomerase I. There was no cross-resistance to DMP 840 in xenografts selected for resistance to vincristine or in a rhabdomyosarcoma selected for resistance to the topoisomerase I inhibitor topotecan. In contrast, a colon tumor selected for topotecan resistance was completely resistant to DMP 840. Slight cross-resistance to DMP 840 was demonstrated in a rhabdomyosarcoma xenograft that was selected for primary resistance to melphalan and was cross-resistant to topoisomerase I inhibitors. The pattern of activity and cross-resistance in these tumors was compared with that shown by two agents that inhibit topoisomerase I: topotecan and CPT-11.This work was supported in part by CA23099, Cancer Center Support (CORE) grant CA21675, The Du Pont Merck Pharmaceutical Company, and by American Lebanese Syrian Associated Charities (ALSAC)  相似文献   
9.
Summary The expression of neuropeptides, and the enzymes nitric oxide synthase and tyrosine hydroxylase were examined in intramural ganglia of human urinary bladder using single label immunocytochemistry. Scattered ganglia composed of between 1–36 neurons (median 4) were observed in all layers of the lateral wall of the bladder. These contained immunoreactivity to vasoactive intestinal peptide, nitric oxide synthase, neuropeptide Y, and galanin. Neurons within the bladder were heterogeneous with regard to their content of these antigens, with the proportion of immunopositive cells ranging from 58–84%. Occasional neurons with immunoreactivity to the catecholamine-synthesizing enzyme, tyrosine hydroxylase, were also observed. No cell somata, however, were immunoreactive for enkephalin, substance P, calcitonin generelated peptide or somatostatin. Varicose terminals entering the ganglia were seen to form pericellular baskets surrounding some of the principal ganglion cells. The most prominent pericellular varicosities were those containing calcitonin gene-related peptide- or vasoactive intestinal peptide-immunoreactivity, followed by those with immunoreactivity for enkephalin, neuropeptide Y, or galanin. Less common were pericellular varicosities with substance P-immunoreactivity, which may represent collateral processes of unmyelinated primary sensory fibres, and presumptive noradrenergic processes containing tyrosine hydroxylase. Some calcitonin gene-related peptide-immunoreactive varicosities constituted a distinct type, terminating as large pericellular boutons 2–4 m in diameter. Fibres containing nitric oxide synthase- or somatostatin-immunoreactivity were not associated with the intramural neurons. The results demonstrate that intrinsic neurons within the human urinary bladder express a number of neuroactive chemicals, and could in principle form circuits with the potential to support integrative activity.  相似文献   
10.
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