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51.
Helmut Brunner Werner Schaeg Ursula Brück Ulrich Schummer Hans-Gerd Schiefer 《Medical microbiology and immunology》1977,163(1):25-35
A radioimmunoassay (RIA) which depends on the property of protein A ofStaphylococcus aureus to combine with the Fc-fragment of immunoglobulins was developed.This technique was employed to measure antibodies in human and various animal sera. It could be demonstrated that the staphylococcal RIA was at least as sensitive as the previously described radioimmunoprecipitation technique in detecting antibodies toM.pneumoniae in human sera. In addition, antibodies toM.pneumoniae could be demonstrated in sera of hamsters intranasally inoculated with the organisms. Antibodies could also be demonstrated in rabbit sera after immunization withM.pneumoniae. The test proved to be considerably more sensitive than conventional tests for detection of antibodies to the organisms. The test requires only small amounts of reagents and is relatively inexpensive.The results were presented in a preliminary form at the annual meeting of the Local Branch of the American Society for Microbiology, Frankfurt, March 1976 and the 77th ordinary meeting of the Society for General Microbiology, Glasgow, September 1976 相似文献
52.
Spök A Gaugitsch H Laffer S Pauli G Saito H Sampson H Sibanda E Thomas W van Hage M Valenta R 《International archives of allergy and immunology》2005,137(2):167-180
The prevalence of allergic diseases has been increasing continuously and, accordingly, there is a great desire to evaluate the allergenic potential of components in our daily environment (e.g., food). Although there is almost no scientific evidence that genetically modified organisms (GMOs) exhibit increased allergenicity compared with the corresponding wild type significant concerns have been raised regarding this matter. In principle, it is possible that the allergenic potential of GMOs may be increased due to the introduction of potential foreign allergens, to potentially upregulated expression of allergenic components caused by the modification of the wild type organism or to different means of exposure. According to the current practice, the proteins to be introduced into a GMO are evaluated for their physiochemical properties, sequence homology with known allergens and occasionally regarding their allergenic activity. We discuss why these current rules and procedures cannot predict or exclude the allergenicity of a given GMO with certainty. As an alternative we suggest to improve the current evaluation by an experimental comparison of the wild-type organism with the whole GMO regarding their potential to elicit reactions in allergic individuals and to induce de novo sensitizations. We also recommend that the suggested assessment procedures be equally applied to GMOs as well as to natural cultivars in order to establish effective measures for allergy prevention. 相似文献
53.
Hinney A Antwerpen B Geller F Schäfer H Siegfried W Goldschmidt H Remschmidt H Ziegler A Hebebrand J 《Molecular genetics and metabolism》2002,76(2):152-156
In light of evidence of linkage of obesity to chromosome 2q31-q37, we hypothesized that the calpain-10 gene 'high-risk' haplotype combination for non-insulin-dependent diabetes mellitus (NIDDM) is involved in early onset obesity. We screened the NIDDM 'high-risk'-haplotype combination formed by the alleles 112 and 121 of the polymorphisms UCSNP-43, -19, and -63 in 166 families consisting of an extremely obese child or adolescent (mean BMI percentile: 99.3+/-1.38), one or more obese sibs (mean BMI percentile: 97.42+/-2.88), and both of their parents. Genotyping for three calpain-10 gene polymorphisms was performed by polymerase chain reaction (PCR) with (a) length polymorphism detection (UCSNP-19) or (b) allele-specific PCR (UCSNP-43 and -63). To allow for correct haplotype assignment all individuals were additionally genotyped for two microsatellite markers (D2S125 and D2S2338). We followed a hierarchical test procedure. As the first step, model-free linkage analysis was performed using maximum likelihood binomial statistics. The second stage consisted of a one-sided asymptotic pedigree disequilibrium test for the UCSNP-43 and on an exploratory level for the other SNP-markers and all haplotypes formed by the three SNPs. The final stage investigated the reported haplotype combination. We failed to detect an initial linkage of obesity to this region (LOD score <0.4). All subsequent exploratory analyses were negative. Our analysis of the relationship between the NIDDM 'high-risk' haplotype combination and extreme early onset obesity revealed no evidence for linkage and association. 相似文献
54.
In the chestnut blight fungus Cryphonectria parasitica, as in most fungi, little is known about the efficiency of the asexual transmission of optional mitochondrial plasmids, vertically
through conidia, and horizontally through hyphal anastomoses. In this paper, we show that pCRY1, a circular mitochondrial
plasmid, is transmitted vertically with 100%-efficiency through conidia. Moreover, the plasmid is transmitted horizontally
through hyphal contact from donor strains to vegetatively compatible and most incompatible strains. An allelic difference
between the donor and recipient strain, at only one of the five nuclear incompatibility genes that were tested strongly inhibited,
but did not absolutely prevent, the transfer of pCRY1 through hyphal fusions. In contrast, allelic differences in any one
or several of the other four heterokaryon-compatibility loci suppressed the transmission of the plasmid only partially or
not at all. The plasmid was also transmitted among incompatible strains by protoplast fusion without the concomitant transfer
of mitochondrial DNA (mtDNA). A comparison of plasmid-bearing with plasmid-free isogenic strains revealed that pCRY1 significantly
diminishes the pathogenic potency of some strains of the fungus, but does not affect the virulence of others. Collectively,
the observations indicate that the introduction of deleterious mitochondrial genetic elements into natural populations may
be a means for managing fungal pathogens.
Received: 22 August 1999 / 9 December 1999 相似文献
55.
The position of pulmonary carcinoids within the spectrum of neuroendocrine tumors of the lung and other tissues 总被引:3,自引:0,他引:3
Ullmann R Petzmann S Klemen H Fraire AE Hasleton P Popper HH 《Genes, chromosomes & cancer》2002,34(1):78-85
Bronchopulmonary carcinoids comprise 25% of all human carcinoids. The World Health Organization divides them into typical (TC) and atypical forms (ATC), distinguished by differences in mitotic counts lower or higher than 2/2 mm(2) and the presence or absence of necrosis. The reproducibility of this classification with respect to the borderline cases with 1-2 mitotic counts/2 mm(2) has been questioned. We have analyzed 15 TCs and 20 ATCs by comparative genomic hybridization. Loss of 11q was the most frequent aberration in ATC (55%), but was observed only twice in TC (13%). Deletions of 3p were seen only in ATC (25%). Meta-analysis of our data and data from 218 neuroendocrine tumors and 50 non-small-cell lung carcinomas obtained from the literature revealed differences between carcinoids and carcinomas. For example, loss of 5q is frequent in lung carcinomas (75%) but is rarely seen in carcinoids (1.4%). Deletions of 11q are less frequent in neuroendocrine lung carcinomas than in ATC. To obtain a more objective survey of the relationship of pulmonary carcinoids to other neuroendocrine tumors and lung carcinomas, we created a hierarchical clustering dendrogram. This statistical approach resulted in a clear separation of carcinoids and carcinomas, which both built up different clusters. In summary, this study demonstrates the benefit of chromosomal analysis supplementary to the diagnosis of bronchopulmonary carcinoids. We also identified the feasibility of hierarchical clustering to get some clues on relationship between different tumor types. This study further argues against a transition of ATC to high-grade neuroendocrine lung carcinoma. 相似文献
56.
57.
Volker Hofmann Helmut Ringsdorf Erich Schaumlffel 《Macromolecular chemistry and physics.》1980,181(2):351-366
Poly[2-(methylsulfinyl)ethyl acrylate] ( 1 ) was synthesized as well as derivatives 14C-labelled in side groups ( 6 ) or 14C-labelled in the main chain ( 11 ). Polymer 11 with the 14C-labelled main chain was fractionated by precipitation. The η-M-relation determined by measurements of unlabelled polymers in the ultracentrifuge for comparison was used to establish the viscosimetrically determined molecular weights of the labelled fractions. After intravenous application of aqueous solutions of the polymer in rats the excretion rate up to 72 h after treatment was ascertained to ca. 50%; the concentration in the blood serum was found to be strikingly high. A tendency to reinforced storage in organs of high phagocytose activity by growing molecular weight was observed. The tumor affinity was — if at all — low. 相似文献
58.
Antibody to Mycoplasma pneumoniae in Nasal Secretions and Sputa of Experimentally Infected Human Volunteers 总被引:8,自引:7,他引:8
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Helmut Brunner Harry B. Greenberg Walter D. James Robert L. Horswood Robert B. Couch Robert M. Chanock 《Infection and immunity》1973,8(4):612-620
After experimental infection with Mycoplasma pneumoniae, 42% of 67 volunteers developed a threefold or greater rise in antibody in nasal secretions as measured by radioimmunoprecipitation. Development of an antibody increase in sputum was detected more often, i.e., in 73% of the volunteers. Each of the antibody increases involved immunoglobulin (Ig) A. Twelve rises in IgG antibody were detected in the specimens which exhibited a rise in IgA antibody. In almost every instance the rise in IgA antibody exceeded that seen with IgG antibody. Analysis of the response to experimental challenge with M. pneumoniae of volunteers with different levels of preexisting respiratory tract IgA antibody suggested that this secretory antibody was related to host resistance to M. pneumoniae disease. Further, respiratory tract IgA antibody appeared to be more directly related to host resistance than was antibody in serum. 相似文献
59.
Dr. med. Gerhard Mall Helmut Reinhard Doris Stopp Johannes Albrecht Rossner 《Virchows Archiv : an international journal of pathology》1980,385(2):169-180
Summary Male Wistar rats were treated with high cortisol doses for 1 week. The dose administered daily was 15 mg per animal in group 1 (7 animals) and 30 mg in group 2 (7 animals). 7 rats served as control group. After cortisol treatment the body weights decreased due to skeletal muscle catabolism and the heart weights increased. Morphometric analysis of the left ventricular posterior papillary muscles gave evidence that the increased heart weights resulted from an increased number of mitochondria and an increased volume of the cytoplasm, whereas the myofibrillar mass was not affected. The surface area of inner mitochondrial membranes (+cristae mitochondriales) per myofibrillar unit volume increased from 15.7 2/3 to 21.3 2/3 in group 1 and 21.4 2/3 in group 2. Ultrastructural changes indicating myocardial cell damage were absent. Similar quantitative results have been reported to occur in the early phase of cardiac overload. For elucidating the hemodynamic effects of glucocorticoid a second experiment was performed: 7 Wistar rats were treated with cortisol in the same way as group 1, 7 others of the same body weight served as control. The systolic arterial pressure was significantly elevated in the cortisol group. Though myocardial tissue is known to be able to accumulate large quantities of glucocorticoids our results indicate that the application of high cortisol doses for a short time does not produce myocardial cell damage and does not suppress the myocardial adaption to the glucocorticoid-induced hypertension, i.e. hypertrophy. On the contrary, it seems to be possible that the adaption process is itself facilitated or accelerated by the presence of high cortisol concentrations in the heart. This thesis is supported by the considerably higher relative heart weights in the cortisol groups and is in agreement with observations reported by other authors.Dedicated to Professor Dr. W. Doerr on the occasion of his 65th birthdayThe results have been partially reported in 1977 (cf. G. Mall and H. Reinhard, Verh. Dtsch. Ges. Path. 61, 445)This investigation was supported by the Sonderforschungsbereich 90 of the Deutsche Forschungsgemeinschaft. 相似文献
60.
Drell A. Bottorff Sukran Parmaksizoglu Edmond G. Lemire John W. Coffin Helmut Bertrand Frank E. Nargang 《Current genetics》1994,26(4):329-335
The cyt-12-12 mutant of Neurospora crassa is characterized by slow growth and a deficiency of spectrophotometrically-detectable cytochromes aa
3
and c. Using a sib-selection procedure we have isolated the cyt-12
+
allele from a cosmid library of N. crassa genomic DNA. Characterization of the cyt-12
+
allele reveals that it encodes the structural gene for cytochrome c. DNA sequence analysis of the cyt-12-12 allele revealed a mutation in the cytochrome c coding sequence that results in replacement of a glycine residue, which is invariant in the cytochrome c of other species, with an aspartic acid. Genetic analysis confirms that cyt-12-12 is allelic with the previously-characterized cyc-1-1 mutant, which was also shown to affect the single locus encoding cytochrome c in N. crassa. We suggest that the amount of functional cytochrome c present in mitochondria influences the level of cytochrome aa
3
. 相似文献