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Several studies have demonstrated that a descending dopaminergic pathway innervates the dorsal and the intermediate gray matter of the spinal cord and have suggested that this pathway is involved in pain modulation and in the control of autonomie functions. Other studies have also demonstrated the presence of dopamine (DA) and DA metabolites as well as of DA receptors in the ventral cord. There is also evidence for the implication of DA in the control of motor functions at the spinal level. The occurrence of a dopaminergic innervation in the ventral horn has been, however, disputed until recently. But recent work has demonstrated that the motoneural cell groups in the ventral horn (lamina IX) are a target for descending dopaminergic fibers. In addition, the possibility that DA is a mediator of primary afferent fibers has also been postulated. Finally, the occurrence of dopaminergic cell bodies has been suggested in the spinal cord. This indicates that DA is probably implicated in a complex manner in spinal functions. In the present paper the possible involvement of DA in sensory and in motor functions at spinal level will be discussed in view of neurochemical observations made in polyarthritic rats, in which pain-related behavior and reduction of locomotor activity associated with a marked decrease in mobility, are observed. 相似文献
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Sheela R Geraghty Barbara S Davidson Barbara B Warner Amy L Sapsford Jeanne L Ballard Betsy A List Rachel Akers Ardythe L Morrow 《Journal of human lactation》2005,21(1):59-66
Although there are well-established clinical human milk banks in the United States, there are no milk banks specifically intended to foster research on human milk. The authors' goal was to establish a milk bank with a core data set to support exploratory and hypothesis-driven studies on human milk. Donations to the Cincinnati Children's Research Human Milk Bank are accepted within the context of ongoing, hypothesis-driven research or on an ad hoc basis. Donors must give informed consent, and scientists wishing to use the samples must have Institutional review board approval for their use. Development of more research human milk banks can potentially provide resources for multidisciplinary collaboration and advance the study of human milk and lactation. 相似文献
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Ana L Hermogenes Michael Richardson Arinos Magalhaes Armando Yarleque Edith Rodriguez Eladio F Sanchez 《Toxicon》2006,47(4):490-494
Lachesis venom plasminogen activator (LV-PA) is a 33-kDa serine proteinase isolated from bushmaster (Lachesis muta muta) snake venom, which activates the fibrinolytic system in vitro. This study has examined the effect of the plasma proteinase inhibitor alpha2-macroglobulin (alpha2-M) towards LV-PA and compares it with the effect on tissue type plasminogen activator (t-PA). The proteolytic activity of LV-PA alone or previously incubated with human plasminogen (Plg) on the large molecular mass protein substrates, dimethylcasein (DMC) and fibrinogen (Fg) was completely inhibited by human alpha2-M. However, the synthetic peptides Tos-Gly-Pro-Lys-pNA and H-D-Pro-Phe-Arg-pNA (S-2302) were hydrolyzed with almost no reduction in rate. At pH 7.4 and 37 degrees C the proteinase (0.15 microM over 15 min) interacted with alpha2-M, and each mole of alpha2-M bound 2 mol of enzyme. Sodium dodecyl sulfate gel electrophoresis of reduced samples showed that the interaction of alpha2-M with either LV-PA or t-PA preincubated with Plg resulted in the formation of approximately 90 kDa fragments and high molecular mass complexes (Mr 180 kDa), generated by the incubation mixture (LV-PA or t-PA) and Plg. The data suggest that LV-PA is a direct-type PA and its fibrinolytic effect can be reduced by alpha2-M in vivo. 相似文献
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Adolf Pfefferbaum Edith V. Sullivan Margaret J. Rosenbloom Paula K. Shear Daniel H. Mathalon Kelvin O. Lim 《Psychiatry Research: Neuroimaging》1993,50(4):257-274
This cross-sectional study used a semi-automated analysis technique to quantify regional brain cerebrospinal fluid (CSF) volumes derived from computed tomography (CT) in 84 healthy men ranging from 21 to 82 years of age and 28 patients meeting Research Diagnostic Criteria for alcohol dependence. The goals were to replicate an earlier CT study of an independent sample of alcoholic and control subjects (Pfefferbaum et al., 1988a; Zipursky et al., 1988) and to compare CT assessments of brain changes with magnetic resonance imaging (MRI) assessments made in the same alcoholic patients (Pfefferbaum et al., 1992). Regional brain changes associated with normal aging were derived by regression analysis, using CT data collected from the healthy control subjects. As in the earlier CT study and in the concurrent MRI study, ventricular and sulcal CSF volumes in alcoholic patients were greater than would be expected for their age. Furthermore, the present CT study replicated the previous CT and MRI findings of a positive relationship between age and CSF volume enlargement in alcoholic patients over and above the normal age-related increase in CSF volume, suggesting greater vulnerability of the aging brain to alcohol. Comparison of CT-and MRI-derived estimates of ventricular and cortical sulcal volume revealed high correlations (>0.80). MRI and CT produced similar absolute ventricular volumes, while MRI produced larger sulcal volume estimates than did CT. The difference in sulcal volume estimate may be due to differences between CT and MRI in slice thickness and sensitivity to partial volume effects. 相似文献