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51.
The Haemophilus ducreyi outer membrane component DsrA (for ducreyi serum resistance A) is necessary for complete resistance to normal human serum (NHS). When DsrA expression in 19 temporally and geographically diverse clinical isolates of H. ducreyi was examined by Western blotting, 5 of the strains expressed a different immunotype of the DsrA protein (DsrA(II)) than the well-characterized prototypical strain 35000HP (DsrA(I)). The predicted DsrA proteins expressed by the DsrA(II) strains were 100% identical to each other but only 48% identical to that of strain 35000HP. In addition to the DsrA(II) protein, class II strains also expressed variant forms of other outer membrane proteins (OMPs) including NcaA (necessary for collagen adhesion A), DltA (ducreyi lectin A), Hlp (H. ducreyi lipoprotein), major OMP, and/or OmpA2 (for OMP A2) and synthesized a distinct, faster-migrating lipooligosaccharide. Based on these data, strains expressing DsrA(I) were termed class I, and those expressing DsrA(II) were termed class II. Expression of dsrA(II) from strain CIP 542 ATCC in the class I dsrA(I) mutant FX517 (35000HP background), which does not express a DsrA protein, rendered this strain resistant to 50% NHS. This demonstrates that DsrA(II) protein is also critical to serum resistance. Taken together, these results indicate that there are two clonal populations of H. ducreyi. The implications of two classes of H. ducreyi strains differing in important antigenic outer membrane components are discussed. 相似文献
52.
Souriau J Gimenes M Blouin C Benbrik I Benbrik E Churakowskyi A Churakowskyi B 《American journal of medical genetics. Part A》2005,135(3):278-281
Kabuki syndrome (KS) is associated with multiple organ system involvement. Characteristic features include long palpebral fissures with everted lower lids, prominent ears, skeletal abnormalities, mental retardation, and short stature. An increased incidence of infection has been reported in KS, and a few patients have been noted to have immune defects. However, the frequency and severity of the immune deficiency has not been clearly defined. Immunologic evaluation of 19 consecutive individuals with KS was performed at The Children's Hospital of Philadelphia. Decreased IgA levels were noted in 15/19 individuals (79%), 2 of whom had undetectable levels. Eight patients (42%) also had low total IgG levels. Specific IgG subclass abnormalities were found in 6 of 13 patients evaluated. IgM levels were less frequently decreased. One patient failed to generate anti-tetanus antibodies despite immunization. This study suggests that hypogammaglobulinemia is a frequent finding in children with KS. The pattern of antibody abnormalities seen in children with KS resembles common variable immune deficiency (CVID). Due to this increased susceptibility to infection, children with KS should have immunologic evaluations at the time of diagnosis in order to reduce preventable morbidity and mortality. 相似文献
53.
A. Richieri-Costa A. Rogatko R. Levisky N. Finkel O. Frota-Pessoa John M. Opitz 《American journal of medical genetics. Part A》1981,9(2):119-128
We describe clinical and genetic data from the study of two families with 80 members affected with the autosomal dominant, slowly progressive spinal muscular atrophy of late onset (average 48.8 years), first described by Finkel in 1962. Electromyography and muscle biopsy of a number of patients confirmed the neurogenic nature of the condition. Unusual findings in this disorder were cramps, spontaneous fits of suffocation, and symptomatic myotonia. Other manifestations are slow loss of muscle strength and progressive proximal atrophy, which starts in the lower limbs and progresses to the upper limbs; hypoactive or absent tendinous reflexes; and generalized fasciculations. Sensory and cranial nerve function is unimpaired. Probabilities for genetic counseling are evaluated by means of a method adequate to the late-onset nature of the condition. 相似文献
54.
Mariz Vainzof Mayana Zatz Paulo A. Otto John M. Opitz James F. Reynolds 《American journal of medical genetics. Part A》1985,22(1):81-87
Serum creatine-kinase (CK) isoenzyme MB was measured in 53 patients affected by different types of myopathies (20 with Duchenne muscular dystrophy (DMD), eight with the Becker form (BMD), ten with the limb-girdle form (LGMD), six with the facioscapulohumeral form (FSH), and nine affected by polymyositis and in 21 normal control subjects). The aim of this study was to compare each group with the control individuals and to assess the nosologic value of CK-MB activity among some clinically similar dystrophies, which may have an important application for genetic counseling. A statistically significant increased CK-MB activity was found only in the Duchenne and Becker patients when compared with control persons (p < 0.05). When the different groups of patients were compared among themselves, no significant difference was found between DMD and BMD or LGMD and polymyositis. However, a significant difference was found between BMD and LGMD. Based on these data, it is possible, through discriminant analysis, to estimate the relative biochemical probability of an isolated male patient belonging to either group. 相似文献
55.
Gerhard Neuhser Richard F. Daly Norma C. Magnelli Robert F. Barreras Robert M. Donaldson John M. Opitz 《Clinical genetics》1976,9(1):81-91
The familial occurrence of essential tremor combined with (congenital) nystagmus, duodenal ulceration and a narcolepsy-like sleep disturbance caused by an autosomal dominant gene with high penetrance and fairly uniform expressivity is reported in a family of Swedish-Finnish ancestry. Twelve of 17 affected family members had essential tremor which began between 30-40 years of age and which could be controlled temporarily by alcohol; this resulted in alcoholism in several affected individuals. The most severly affected persons showed cerebellar signs which may reflect a possible pathogenetic relationship of the syndrome to the genetic cerebellar atrophies. Nystagmus, observed in 12 of 17 affected family members (eight of whom were also affected with tremor) usually was congenital and accompanied by refractive errors. Duodenal ulcers occurred almost exclusively in individuals with the neurological syndrome, and preceded its onset in some cases. The ulcer disease therefore seems to be a component manifestation of the syndrome and is interpreted as a pleiotropic effect of the gene which also causes the nystagmus, tremor and sleep disturbance. 相似文献
56.
Roger A. Williamson Michael A. Donlan Cynthia R. Dolan Horace C. Thuline Mary T. Harrison Judith G. Hall John M. Opitz 《American journal of medical genetics. Part A》1981,9(2):105-111
The use of elongated prophase and prometaphase chromosome preparations has allowed detection of an insertion of a small segment of 3q into 11q in a kindred with 4 balanced carriers and 8 unbalanced offspring. Those with partial 3q deletion have a true multiple congenital anomalies/mental retardation (MCA/MR) syndrome with an appearance suggestive of the Schwartz-Jampel syndrome. 相似文献
57.
Prognostic values of galectin-3 and the macrophage migration inhibitory factor (MIF) in human colorectal cancers. 总被引:7,自引:0,他引:7
Hugues Legendre Christine Decaestecker Nathalie Nagy Alain Hendlisz Max-Peter Schüring Isabelle Salmon Hans-Joachim Gabius Jean-Claude Pector Robert Kiss 《Modern pathology》2003,16(5):491-504
This study aims to investigate whether the immunohistochemical levels of expression of galectin-3 and the macrophage migration inhibitory factor (MIF) are associated with prognostic values in human colorectal tumors. This was performed on 99 specimens including 69 colorectal tumors (17 Dukes A, 19 Dukes B, 15 Dukes C and 18 metastatic tumors that we labeled as D), 10 hepatic metastases from colorectal cancers and 20 normal specimens (biopsies). The immunohistochemical levels of expression of MIF and galectin-3 were quantified on routine histological slides by means of computer-assisted microscopy. Separate analyses were performed on epithelial and connective tissue. The levels of expression of both MIF and galectin-3 were very significantly higher in epithelial tumor tissue when compared with normal epithelial specimens. A positive and significant correlation between MIF and galectin-3 expression was evidenced in connective tumor tissue, and in particular in the cases associated with short survival periods (less than 5 years). In the case of the Dukes A or B tumors, we established two new prognostic groups (labeled I and II) on the basis of the levels of galectin-3 expression measured in the tumor epithelium. In the case of the Dukes C or D tumors, we established two other prognostic groups (labeled III and IV) on the basis of the levels of MIF expression measured in the connective tissue. Kaplan-Meyer analyses confirmed the additional prognostic values (as compared with conventional clinical staging) given by this new classification (groups I to IV). They show that the Dukes A or B tumors characterized by low levels of galectin-3 expression in the tumor epithelium are associated with significantly better prognoses than those characterized by high levels. In addition, the Dukes C or D tumors characterized by high levels of MIF expression in the connective tumor tissue are associated with significantly better prognoses than those characterized by low levels. In conclusions, MIF and galectin-3 expression levels in colorectal tumors are related to their levels of biological aggressiveness. These markers could be used to identify patients at risk, for whom more aggressive adjuvant therapy seems to be indicated. 相似文献
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