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31.
Eighty-five young Mauritian Indians, male survivors of premature myocardial infarction (MI) and thus belonging to a high risk group, were compared with 108 stringently selected controls for a possible association between premature MI and an insertion/deletion (I/D) polymorphism in the gene encoding angiotensin I-converting enzyme (ACE). The frequency of the D allele was 0.42 in the MI group and 0.43 in the control group, and thus no association between I/D polymorphism of ACE with susceptibility to early-onset MI was found in this population group. Other gene components of the renin-angiotensin system and lipid metabolism need to be explored to understand the genetic factors involved in causing MI at an early age.  相似文献   
32.
An indirect enzyme‐linked immunosorbent assay (ELISA) has been developed for the specific detection of cow's milk (1–25%) in goat's milk. The test uses polyclonal antibodies raised in rabbits against bovine whey proteins (BWP). The anti‐BWP antibodies were recovered from the crude antiserum by immunoadsorption and elution from a column containing immobilized BWP. The anti‐BWP antibodies were biotinylated and rendered cow's milk specific by mixing them with lyophilized ovine and caprine whey proteins. Streptavidin‐peroxidase was used to detect the biotinylated anti‐BWP antibodies bound to bovine milk proteins immobilized on 96‐well plates. The colour developed by the subsequent enzymic conversion of the substrate gave clear absorbance differences when assaying mixtures of goat's milk containing variable amounts of cow's milk.  相似文献   
33.
A solid phase radioimmunoassay has been compared with an enzyme-linked immunosorbent assay (ELISA) for efficacy in measuring anti-chromatin antibodies. The low backgrounds achieved with the radioimmunoassay method produced a high signal-to-noise ratio and enabled detection of the human test antiserum at a dilution of 1:102,400. By contrast, the ELISA could detect the same antiserum only at a dilution of 1:3200 and above. The radioimmunoassay was consistently more sensitive than the ELISA for detection of anti-chromatin antibodies in a number of human and mouse sera and ascites fluid containing a monoclonal antibody. Factors affecting sensitivity in both assays are discussed.  相似文献   
34.
A significant problem in the immunoassay of angiotensin II is the cross-reactivity of most available antisera with the peptide's metabolic products, (des-Asp1)-angiotensin II and (des-Asp1.Arg2)-angiotensin II. In order to attempt to generate antisera of greater selectivity, a variety of conjugates between angiotensin II or derivative peptides and carrier proteins were examined as immunogens with the aim of generating antisera that would selectively identify the amino terminal region of the peptide. Selectivity for the amino terminus was achieved by either (1) immunization with N-acetylated angiotensin II-amide which had been coupled to rabbit serum albumin by its carboxy terminus, or (2) immunization with angiotensin-(1-7)-heptapeptide which was randomly coupled to thyroglobulin. The antisera produced with the N-acetylated immunogen cross-reacted with the unacetylated ligand (Asn1-Val5)-angiotensin, but did not recognize the human hormone (Asp1,Ile5)-angiotensin. Carboxy-terminal coupling of angiotensin without N-acetylation did not induce selectivity for the amino terminus, nor did a conjugate which was linked to the carrier protein via a diazo bond to His6 of the peptide. These findings may be explained by the fact that N-acetylated angiotensin II resists degradation by amino peptidases and thus retains its structure in the immunogen and by the fact that the (1-7)-heptapeptide has lost the immunodominant carboxy-terminal epitope, thus emphasizing the desired amino terminal determinant.  相似文献   
35.
Reactions of the glia and blood vessels in the sensomotor cortex of adult rats to intraperitoneal injection of angiotensin II were studied electron-microscopically. Repeated injections of the hormone led to edema of increasing severity of the astrocytes, constriction of the lumen of the capillaries, and changes in the structure of their endothelium. It is suggested that these disturbances may be the cause of the cerebrovascular insufficiency and of functional changes in the CNS.Laboratory of Morphology of the Central Nervous System and Laboratory of Experimental Pathology and Therapy of Higher Nervous Activity, Institute of Higher Nervous Activity and Neurophysiology, Academy of Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. S. Rusinov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 11, pp. 615–617, November, 1979.  相似文献   
36.
Hexokinase and glucokinase activity in the supernatant of a rabbit liver homogenate obtained at 18,000g was determined by a spectrophotometric method. Preliminary purification to remove low-molecular-weight components by gel filtration on Molselect G-50 dextran was shown to prevent reduction of NADP unconnected with the hexokinase reaction.Presented by Academician of the Academy of Medical Sciences of the USSR V. S. Il'in.Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 7, pp. 891–892, July, 1976.  相似文献   
37.
The expression and cellular localization of angiotensin II (Ang II) and AT(1) receptor proteins were examined in the normal human prostate and benign prostatic hyperplasia (BPH) by immunohistochemistry. In the normal prostate, Ang II immunoreactivity was localized to the basal layer of the epithelium and AT(1) receptor immunostaining was found predominantly on stromal smooth muscle and also on vascular smooth muscle of prostatic blood vessels. Ang II immunoreactivity was markedly increased in hyperplastic acini in BPH compared with acini in the normal prostate (normal: 7.4+/-0.2%, n=5 vs. BPH: 22.7+/-1.9%, n=5, p<0.001). However, AT(1) receptor immunoreactivity was significantly decreased in BPH compared with the normal prostate [normal: 16.4+/-2.2%, n=4 vs. BPH: 9.4+/-1.3%, n=5, p<0.05 (p=0.025)]. The present study demonstrates the presence of Ang II peptide in the basal layer of the epithelium and AT(1) receptors on stromal smooth muscle, suggesting that Ang II may mediate paracrine functions on cellular growth and smooth muscle tone in the human prostate. Furthermore, AT(1) receptor down-regulation in BPH may be due to receptor hyperstimulation by increased local levels of Ang II in BPH. These data extend previous findings in support of the novel concept that overactivity of the renin-angiotensin system (RAS) may be involved in the pathophysiology of BPH.  相似文献   
38.
Summary A technique for culturing small quantities of mammalian cells on modified microscope slides is described. The modified microscope slides were Bellco Glass, Inc., toxoplasmosis slides and the cell cultures used were early passage bovine embryonic lung cells and continuous cell lines of porcine and canine origins. The slide cell cultures were either uninfected or infected with selected viruses or the obligate intracellular protozoanEncephalitozoon caniculi for utilization in direct and indirect fluorescent antibody testing or in peroxidase antiperoxidase immunosorbant assays.  相似文献   
39.
40.
DNA polymorphisms among independent isolates of herpes simplex virus (HSV) type 1 were studied from a 7-year-old male patient with recurrent infections of the skin and internal organs. In the patient's serum, HSV antibodies could not be detected by complement fixation, enzyme-linked immunosorbent assay (ELISA), or neutralization tests. ELISA tests for the presence of antibodies to human immunodeficiency virus were also negative. One HSV isolate was obtained from mesenteric nodes biopsied in 1983; one from skin in 1984; and three (postmortem) from brain, lungs, and liver in 1985. Restriction enzymes Eco RI, Bgl II, Hind III, Kpn I, and Bam H1 digestion patterns of the five isolates were similar. However, Sal I digests of isolates from skin, mesenteric nodes, lungs, and liver showed variations that were distinct from that of the brain isolate. Although Sal I digests of skin, mesenteric nodes, lungs, and liver isolates share a common variation in lacking F and G, the liver isolate can be further differentiated because of the gain of a restriction site on the H fragment. Thus, the three distinct variants observed were the isolates from brain (variant 1); from skin, mesenteric nodes, and lungs (variant 2); and from liver (variant 3). The fragments involved in variations among these isolates (presence or absence of Sal, G and H) are from the unique short and long regions (invariable regions) of the genome and therefore do not show heterogeneity in size. The extent of variation among these isolates is less than that seen among epidemiologically unrelated strains, suggesting that they originated from a single infecting strain, probably the brain isolate.  相似文献   
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