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71.
Immunoglobulin A levels in southern elephant seal (Mirounga leonina) milk during the suckling period
ME Marquez NH Slobodianik PA Ronayne de Ferrer AR Carlini DF Vergani GA Daneri 《Canadian Metallurgical Quarterly》1995,112(3):569-572
Immunoglobulin A (IgA) levels in milk samples from southern elephant seals at King George Island, Antarctica are reported. IgA levels were determined throughout the suckling period (approximately 23 days). The IgA concentration in southern elephant seal milk was lower than in other mammals and, unlike most mammalian milk, was not high during early lactation. There was not a definite pattern in IgA levels, which fluctuated within narrow limits throughout the suckling period (mean +/- SD, 30.81 +/- 6.38 mg IgA/100 g milk). If IgG was present, its level was too low to be detected by the method used. This is the first evidence in Southern elephant seal of the possibility of transmission of passive immunity after birth involving secretion of IgA in the milk. 相似文献
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WJ Hoogendijk JS Purba MA Hofman RA de Vos EN Jansen DF Swaab 《Canadian Metallurgical Quarterly》1998,43(12):913-917
BACKGROUND: Depression is frequently encountered in Parkinson's disease (PD). In addition, more than half of the PD patients have a disturbed dexamethasone suppression test, which is associated with increased activity of corticotropin-releasing hormone (CRH) neurons. We recently found an increase in CRH neuron number, CRH-messenger RNA, and vasopressin colocalization in CRH neurons in the paraventricular nucleus (PVN) of depressed patients, which may be involved in the pathogenesis of depression. METHODS: The number of neurons expressing CRH was determined in the PVN of 6 depressed PD patients with a high score (> or = 13) on the Hamilton Depression Rating Scale, 6 nondepressed PD patients, and 6 controls. RESULTS: The three groups did not differ in the number of neurons expressing CRH. CONCLUSIONS: We hypothesize that activation of CRH neurons in the PVN, as we recently observed in idiopathic depression, does not play an essential role in depression in PD. 相似文献
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V Mooser A Maillard C Bonny M Steinmann P Shaw DP Yarnall DK Burns DF Schorderet P Nicod G Waeber 《Canadian Metallurgical Quarterly》1999,55(2):202-208
Islet-brain 1 (IB1), a regulator of the pancreatic beta-cell function in the rat, is homologous to JIP-1, a murine inhibitor of c-Jun amino-terminal kinase (JNK). Whether IB1 and JIP-1 are present in humans was not known. We report the sequence of the 2133-bp human IB1 cDNA, the expression, structure, and fine-mapping of the human IB1 gene, and the characterization of an IB1 pseudogene. Human IB1 is 94% identical to rat IB1. The tissue-specific expression of IB1 in human is similar to that observed in rodent. The IB1 gene contains 12 exons and maps to chromosome 11 (11p11.2-p12), a region that is deleted in DEFECT-11 syndrome. Apart from an IB1 pseudogene on chromosome 17 (17q21), no additional IB1-related gene was found in the human genome. Our data indicate that the sequence and expression pattern of IB1 are highly conserved between rodent and human and provide the necessary tools to investigate whether IB1 is involved in human diseases. 相似文献
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J Meerschaert EA Kelly DF Mosher WW Busse NN Jarjour 《Canadian Metallurgical Quarterly》1999,159(2):619-625
Fibronectin may contribute to asthma pathogenesis by recruitment and activation of inflammatory cells, and by promotion of subepithelial fibrosis. Fibronectin is produced by several types of airway cells, including epithelial cells, fibroblasts, and alveolar macrophages. To test the hypothesis that antigen-induced airway inflammation is associated with increased local generation of fibronectin, segmental bronchoprovocation (SBP) with antigen and saline was performed in 17 atopic patients. Bronchoalveolar lavage (BAL) was performed at 5 min and 48 h after segmental challenge with saline or antigen. Fibronectin concentrations in BAL fluid, measured by enzyme-linked immunosorbent assay (ELISA), increased more than 5-fold 48 h after antigen challenge (65 [47 to 110] versus 407 [240 to 697] ng/ml, median and 25 to 75% interquartiles, p < 0.05). Fibronectin concentrations 48 h after antigen challenge correlated with histamine concentrations 5 min after antigen challenge and numbers of eosinophils, neutrophils, macrophages, and total cells in BAL fluid 48 h after antigen challenge. BAL was more enriched in fibronectin 48 h after challenge than would be predicted solely from increased permeability of plasma proteins. Western blot analysis showed that fibronectin in BAL fluid was largely intact and contained the extra domain-A (ED-A) splice variant of cellular fibronectin, indicative of local production. We conclude that antigen challenge in atopic subjects causes increased production of fibronectin by airway cells and speculate that this response may contribute to airway remodeling in allergic inflammation. 相似文献
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Insulin receptors differing structurally from those in other tissues have been demonstrated in brain from many species. Subtle differences in binding properties have been reported between insulin receptors in brain and other tissues, including differences in affinity of pig brain receptors for human and porcine insulin. Insulin binding has been demonstrated in human cerebral cortex, but insulin binding has not been characterized in other areas of human brain. We have studied the binding of 125I labelled human insulin, and its displacement by unlabelled human and porcine insulin, in homogenates prepared from human hypothalamus, cerebral cortex and cerebellum obtained post-mortem from eight non-diabetic subjects. Specific binding was demonstrated in all brain regions studied, and displacement curves obtained with unlabelled human and porcine insulin were identical. By contrast, unlabelled insulin-like growth factor-1 did not significantly displace 125I labelled human insulin over the same concentration range. We therefore conclude that insulin receptors are widely distributed in human brain and do not differ in their affinity for human and porcine insulin. 相似文献
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BACKGROUND: Infertility is common in Africa, but virtually no data exist on HIV prevalence among infertile women. Mainly anthropological studies in Africa have shown that infertile women have higher risks of marital instability and possibly also have more sexual partners than fertile women. METHOD: This study was conducted in a hospital in northwest Tanzania during 1994 and 1995. Women presenting themselves with infertility problems to the outpatient clinic were interviewed, examined and blood was drawn. Women who came to deliver in the hospital, excluding primiparae, were taken as a control group. The analysis was limited to women > or = 24 years. In total 154 infertile and 259 fertile women were included in the study. RESULTS: HIV prevalence was markedly higher among infertile women than among fertile women: 18.2% and 6.6% respectively (adjusted odds ratio [OR] for age, residence and occupation 2.7; 95%-confidence interval [CI]: 1.4-5.3). Data on past sexual behaviour showed that infertile women had more marital breakdowns, more lifetime sexual partners and a higher level of exposure to sexually transmitted diseases (STD). CONCLUSION: Women with fertility problems appear to have higher HIV prevalence, which justifies more attention for such women in the context of AIDS programmes. In addition, caution is needed when using sentinel surveillance data from antenatal clinics to monitor HIV prevalence. 相似文献
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