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91.
Recombinant Trypanosoma cruzi antigens and Chagas' disease diagnosis: analysis of a workshop 总被引:1,自引:0,他引:1
M.J. Levin J. Franco da Silveira A.C.C. Frasch M.E. Camargo S. Lafon W.M. Degrave R. Rangel-Aldao 《FEMS microbiology letters》1991,89(1):11-20
Abstract A workshop organized by the Ibero-American Project of Biotechnology evaluated the diagnostic potential of several cloned Trypanosoma cruzi recombinant antigens for Chagas' disease serodiagnosis. A set of recombinants, Antigen 2, Antigen 13, SAPA, H49, A13, JL5, JL7, JL8, JL9, and RA1 provided by three different South American laboratories were probed with a panel of 236 South American serum samples. Antigens JL7, H49, Antigen 2, and A13 scored as the best diagnostic recombinant reagents. The results suggested that the main advantage of using cloned peptides for chronic Chagas' disease diagnosis resided in their highly specific immunoreactive properties. 相似文献
92.
C F Hildebolt S Molnar M Elvin-Lewis J K McKee 《American journal of physical anthropology》1988,75(1):1-14
In previous epidemiological studies, it has been suggested that geochemical factors besides fluoride may affect the prevalences of dental diseases. Our objective in this study was to determine whether the prevalences of periodontal diseases, coronal caries, and root caries for prehistoric inhabitants vary between geochemical regions of the state of Missouri. Burial sites were located on unique maps that depict geochemical variation among regions of the state. Data on dental caries and alveolar bone loss were gathered from 179 of the best preserved skeletal remains of the Late Woodland (A.D. 400-900) and Mississippian (A.D. 900-1700) periods. Mean caries scores and proportions of individuals with caries were calculated for these geochemical regions. Average alveolar bone loss was regressed on age for the individuals of these regions. Significant differences in caries and bone loss were found between several regions. These differences cannot be adequately explained by fluoride concentrations or by diet. It is suggested that geochemical factors, in addition to fluoride, may have affected the prevalences of dental diseases. 相似文献
93.
P. Jenner H. Taquet A. Mauborgne J. T. Benoliel F. Cesselin S. Rose F. Javoy-Agid Y. Agid C. D. Marsden 《Journal of neurochemistry》1986,47(5):1548-1551
Treatment of common marmosets with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP; 1-4 mg/kg for up to 4 days) caused a profound parkinsonian state. Ten days from the start of MPTP treatment, all animals showed marked motor impairment, consisting of bradykinesia and akinesia, limb rigidity, postural abnormalities, loss of vocalisation and blink reflex, and, on occasions, postural tremor. Measurement of caudate-putamen monoamine content at this time showed a profound loss in 3,4-dihydroxyphenylethylamine, homovanillic acid, and 3,4-dihydroxyphenylacetic acid concentrations. Measurement of neuropeptide concentrations in the caudate-putamen, internal and external segments of the globus pallidus, nucleus accumbens, substantia nigra, frontal cortex, and hippocampus showed met-enkephalin, leu-enkephalin, and cholecystokinin (CCK-8) concentrations to be unaffected by MPTP treatment. There was a small decrease in the substance P content of frontal cortex, but otherwise the content of this neuropeptide was unaltered. Parkinsonism in the marmoset, induced by MPTP treatment 10 days earlier, does not alter neuropeptide concentrations in the manner observed in Parkinson's disease. 相似文献
94.
Changes in Nine Enzyme Markers for Neurons, Glia, and Endothelial Cells in Agonal State and Huntington''s Disease Caudate Nucleus 总被引:2,自引:2,他引:0
John Butterworth 《Journal of neurochemistry》1986,47(2):583-587
Enzymes considered to be markers for neurons (angiotensin converting enzyme, thermolysin-like metalloendopeptidase, alanine aminopeptidase, and glutamate-oxaloacetate transaminase), glia (glutamine synthetase, pyruvate carboxylase, and beta-glucuronidase), and endothelial cells (alkaline phosphatase and plasminogen activator) were measured in caudate nucleus from 10 sudden death controls, eight agonal state controls, and 16 Huntington's disease patients. Glutamate-oxaloacetate transaminase was slightly reduced by agonal state. The four enzymes with a neuronal distribution were all correlatively reduced in Huntington's disease caudate nucleus. Glutamine synthetase activity was reduced and beta-glucuronidase mean activity increased over twofold in Huntington's disease caudate nucleus, with the two enzyme activities being inversely related. Pyruvate carboxylase was markedly affected by agonal state and was very variable in Huntington's disease caudate nucleus. The two endothelial enzymes were unaltered in Huntington's disease caudate nucleus. The findings are indicative of neuronal loss, an increased proportion of altered glia, and also of maintained vasculature in Huntington's disease caudate nucleus. Measurement of enzyme activities can help to delineate the types of cell altered in Huntington's disease. 相似文献
95.
96.
Cholinergic processes were measured in motor cortex, hippocampus, and striatum of cats in the terminal stages of GM1 gangliosidosis and compared to those of control cats. The greatest difference observed was elevation in the rate of K+-stimulated release of acetylcholine (ACh) from brain slices prepared from affected cats. The K+-stimulated release of endogenous ACh was increased by 31-43% and of newly synthesized ACh by 19-80% in brain slices from different brain regions. All regions that were examined were affected but the greatest effects occurred in cortex. The rate of synthesis of ACh was elevated in cortical and hippocampal slices. Choline acetyltransferase activity in brain regions of cats with GM1 gangliosidosis was not significantly different from that in controls, whereas high-affinity choline transport in cortical synaptosomes was elevated. Muscarinic receptor binding sites were reduced in the cortex, hippocampus, and striatum of GM1 mutant cats, whereas the apparent affinity was not altered. These results indicate that there are major alterations of cholinergic function in the brains of cats with GM1 gangliosidosis. 相似文献
97.
为考察Ca~( )在缺氧性肺动脉高压形成中的作用,我们观察了钙通道阻断剂异搏定对慢性连续性缺氧大鼠肺动脉压及左右心功能的影响。将动物置于模拟海拔5000m高原的低压舱内,腹腔注射异搏定,剂量为4mg/kg BW,每日两次。实验结果表明:异搏定可以减弱缺氧15天所引起的肺动脉压升高和右心功能加强的程度,对颈动脉压及左心功能无明显影响,提示Ca~( )的跨膜内流是构成缺氧性肺动脉高压形成的重要基础之一。我们还比较了异搏定对缺氧持续时间不同(15天、10天、5天)的大鼠肺循环的影响,并讨论了异搏定发生作用的机制。 相似文献
98.
99.
Protoscoleces from human, camel, cattle, sheep, goat (all from Kenya) and buffalo (from India) hydatid cysts were cultured under identical conditions in vitro using the diphasic culture system of Smyth (1979b). Organisms from all sources grew and segmented in culture. Genital anlagen developed in all cultured worms but further genital differentiation occurred only in cultures of cattle (testes) and camel (testes and genital pore) material. The possible significance of these results is discussed in relation to the general epidemiology of hydatid disease and the potential infectivity of the different strains to man. 相似文献
100.
马立克氏病毒单克隆抗体的研究 总被引:1,自引:0,他引:1
获得了4株分泌马立克氏病毒(MDV)特异性单克隆抗体(McAb)的杂交瘤细胞:4BS10对MDV所有毒株呈阳性反应;4CN8 对MDV血清1,3型毒株发生反应;2BN90和4CN24只对MDV血清1型毒株有阳性反应。3个McAb属IgG1,1个为IgG2b,均不中和MDV,免疫扩散试验也无沉淀线。对禽白血病毒(ALV)无交叉反应。 以2BN90和辣根过氧化物酶、异硫氰酸荧光素的结合物进行直接酶联免疫吸附试验和直接荧光抗体试验,均获得成功。抗体滴度前者为1/51,200,后者为1/640。对ALV无交叉反应。 相似文献