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31.
Schatz O Monini P Bugarini R Neipel F Schulz TF Andreoni M Erb P Eggers M Haas J Buttò S Lukwiya M Bogner JR Yaguboglu S Sheldon J Sarmati L Goebel FD Hintermaier R Enders G Regamey N Wernli M Stürzl M Rezza G Ensoli B 《Journal of medical virology》2001,65(1):123-132
A multicentre study was undertaken to define novel assays with increased inter-assay concordance, sensitivity, specificity and predictive value for serological diagnosis of human herpesvirus type 8 (HHV-8) infection. A total of 562 sera from European and Ugandan human immunodeficiency virus (HIV)-infected or uninfected individuals with or without Kaposi's sarcoma (KS) and blood donors were examined under code by 18 different assays in seven European laboratories. Sera from KS patients and all non-KS sera found positive by at least 70%, 80%, or 90% of the assays were considered "true positive." The validity of the assays was then evaluated by univariate logistic regression analysis. Two immunofluorescence assays (IFA) for detection of antibodies against HHV-8 lytic (Rlyt) or latent (LLANA) antigens and two enzyme-linked-immunosorbent assays (ELISA) (M2, EK8.1) for detection of antibodies against HHV-8 structural proteins were found to be highly concordant, specific, and sensitive, with odds ratios that indicated a high predictive value. When used together, the two IFA (Rlyt-LLANA) showed the best combination of sensitivity (89.1%) and specificity (94.9%). The performance of these assays indicate that they may be used for the clinical management of individuals at risk of developing HHV-8 associated tumours such as allograft recipients. 相似文献
32.
Increased frequency of congenital chromosomal aberrations in female partners of couples undergoing intracytoplasmic sperm injection 总被引:3,自引:7,他引:3
van der Ven K; Peschka B; Montag M; Lange R; Schwanitz G; van der Ven HH 《Human reproduction (Oxford, England)》1998,13(1):48-54
We evaluated the frequency of congenital chromosomal aberrations in a
sample of 305 couples included in an intracytoplasmic sperm injection
(ICSI) programme. Twenty individuals (3.3%) with congenital chromosomal
abnormalities could be identified. The following types of abnormalities
were observed: reciprocal translocations (n = 7), Robertsonian
translocations (n = 3), inversions (n = 3), other structural aberrations (n
= 4) and sex chromosome aberrations (n = 3). The rate of chromosomally
abnormal males (10/305, 3.3%) lay within the expected range for patients
with reduced semen quality. Surprisingly, 50% (10/20) of all abnormal
karyotypes were contributed by the female partner of ICSI patients. These
data confirm the higher incidence of chromosomal aberrations in infertile
populations as compared with the baseline population risk. Additionally,
the data imply that in some cases of male factor infertility a hidden
female chromosomal factor may be present, which cannot be identified by
standard clinical evaluation. In conclusion, we recommend chromosomal
analysis in both partners of couples undergoing ICSI treatment.
相似文献
33.
Identification of a gene disrupted by a microdeletion in a patient with X-linked retinitis pigmentosa (XLRP) 总被引:2,自引:2,他引:2
Roepman R; Bauer D; Rosenberg T; van Duijnhoven G; van de Vosse E; Platzer M; Rosenthal A; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(6):827-833
The gene for the most frequent from of X-linked retinitis pigmentosa
(XLRP), RP3, has been assigned by genetic and physical mapping to a segment
of less than 1000 kbp, which is flanked by the marker DXS1110 and the
ornithine transcarbamylase (OTC) gene. In search of microdeletions, we have
screened the DNA of 30 unrelated patients with XLRP by employing a
representative set of YAC-derived DNA fragments that were generated by
restriction enzyme digestion and PCR amplification. In one of these
patients, a 6.4 kbp microdeletion was detected which was not present in the
DNA of 444 male controls. A cosmid contig spanning the deletion was
constructed and used to isolate cDNAs from retina-specific libraries. Exons
corresponding to these expressed sequences as well as other putative exons
were identified by sequencing more than 30 kbp of the critical region. So
far, no point mutations in these putative exon sequences have been
identified.
相似文献
34.
Positional cloning of the gene for X-linked retinitis pigmentosa 3: homology with the guanine-nucleotide-exchange factor RCC1 总被引:6,自引:7,他引:6
Roepman R; van Duijnhoven G; Rosenberg T; Pinckers AJ; Bleeker-Wagemakers LM; Bergen AA; Post J; Beck A; Reinhardt R; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(7):1035-1041
The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X-
linked RP (XLRP), has been mapped previously to a chromosome interval of
less than 1000 kbp between the DXS1110 marker and the OTC locus at
Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization
(YRH)', we have recently identified a small XLRP associated microdeletion
in this interval, as well as several putative exons including the 3' end of
a gene that was truncated by the deletion. cDNA library screening and
sequencing of a cosmid centromeric to the deletion has now enabled us to
identify numerous additional exons and to detect several point mutations in
patients with XLRP. The predicted gene product shows homology to RCC1, the
guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our
findings suggest that we have cloned the long-sought RP3 gene, and that it
may encode the GEF of a retina-specific GTP-binding protein.
相似文献
35.
We studied whether cytokine receptors (Rs) on T cells associate with lipid microdomains ("rafts"). Low-dose phytohemagglutinin (PHA)-stimulated human T cells were separated into cytoplasmic, membrane, and raft fractions by buoyant density centrifugation. Examination of these fractions for the presence of interleukin (IL)-2- and -15R chains and associated signaling molecules by Western blotting revealed marked, selective enrichment of the IL-2/15R beta-chain in rafts before IL-2 stimulation. After IL-2 stimulation, a substantial amount of the beta-chain was found in the membrane fraction. This partial translocation was also observed for the beta-chain-associated molecules JAK-1, p56(lck), and grb-2. Finally, raft disruption with methyl-beta-cyclodextrin (MBCD) attenuated IL-2-induced tyrosine phosphorylation events and selectively decreased the surface expression of the IL-2/15R beta-chain detected by flow cytometry. These results show that the IL-2/15R beta-chain is enriched in rafts obtained from low-dose, PHA-stimulated T cells, that IL-2 binding alters this enrichment, and that this enrichment may be functionally relevant as a possible mechanism to ensure cytokine selectivity and specificity. 相似文献
36.
Moshe Frydman Rachel Straussberg Ruth Shomrat Hans Goebel Cyril Legum Yossi Shiloh 《American journal of medical genetics. Part A》1995,58(3):209-212
A 7-month-old boy with gross motor delay and failure to thrive presented with rhabdomyolysis following an acute asthmatic episode. During hospitalization an electrocardiographic conversion to a Wolff-Parkinson-White type 1 (WPW) pattern took place. Duchenne muscular dystrophy (DMD) was suspected based on elevated creatine kinase (CK) serum levels, muscle biopsy, and family history. The diagnosis was confirmed by molecular analysis, which documented a deletion corresponding to cDNA probe 1-2a in the dystrophin gene, in the propositus and in an affected male cousin of his mother. “Idiopathic” hyperCKemia was found in the propositus, his father, and 5 of his relatives. We suggest that the unusually early and severe manifestations of DMD in this patient may be related to the coincidental inheritance of the maternal DMD gene and of a paternal gene, causing hyperCKemia. © 1995 Wiley-Liss, Inc. 相似文献
37.
C. Hellerbrand F. D. Goebel R. Disko 《European journal of clinical microbiology & infectious diseases》1996,15(11):869-872
The results of serological tests forToxoplasma gondii IgG in 31 HIV-infected patients with toxoplasmic encephalitis (TE) and 49 HIV-infected patients seropositive forToxoplasma gondii but without TE were compared. All patients had a CD4+ lymphocyte count < 1 50/l. Of the TE patients, 22 (71%) were designated as having relatively high IgG levels on the basis of the followingToxoplasma IgG titre combination: Sabin-Feldman test 1256, indirect hemagglutination test 11024, direct agglutination test 114,580. Only 3 patients without TE had relatively high IgG titres. Relatively high IgG titres indicated TE with a positive predictive value of 88% in HIV-infected patients with CD4+ cell counts < 150/l, and could be observed in most patients several months prior to the first clinical and radiological signs of TE. 相似文献
38.
H. Ehrenreich C. Kolmar C. Pittius F. -D. Goebel 《Journal of molecular medicine (Berlin, Germany)》1988,66(4):175-180
Summary Administration of synthetic human corticotropin-releasing factor (hCRF, 2 µg/kg body weight) during simultaneous application of the opioid antagonist naloxone (1.6 mg i.v. bolus, followed by an infusion at a rate of 1.2 mg/h) produced a significant increase in plasma C-peptide levels of six male Type 2 diabetic patients which even exceeded the postprandial values. This stimulatory effect of hCRF/naloxone on plasma C-peptide was less pronounced in six healthy men. hCRF alone did not provoke any reaction of plasma C-peptide in either group.The possibility of a paracrine, CRF-dependent mechanism in pancreatic islets which somehow involves inhibitory opioid receptors is preferentially discussed. Such a mechanism may underlie the stimulatory action of hCRF/naloxone on B cells and would explain the absent reaction of peripheral venous plasma C-peptide to hCRF alone as well as the amplifying effect of simultaneous opioid receptor blockade.Abbreviations ACTH
adrenocorticotropic hormone
- C-peptide
connecting-peptide
- CRF
corticotropin-releasing factor
- hCRF
human CRF
- oCRF
ovine CRF
- min
minutes
- S.D.
standard deviation
- S.E.M.
standard error of the mean
This study was supported by the Deutsche Forschungsgemeinschaft (Go 299/3-2)Dedicated to Professor Dr. N. Zöllner on the occasion of his 65th birthday 相似文献
39.
40.
Kolb-Mäurer A Gentschev I Fries HW Fiedler F Bröcker EB Kämpgen E Goebel W 《Infection and immunity》2000,68(6):3680-3688
Dendritic cells (DCs) are potent antigen-presenting cells and play a crucial role in initiation and modulation of specific immune responses. Various pathogens are able to persist inside DCs. However, internalization of the gram-positive bacterium Listeria monocytogenes into human DCs has not yet been shown. In the present study, we demonstrate that human monocyte-derived immature DCs can efficiently phagocytose L. monocytogenes. This uptake is independent of listerial adhesion factors internalin A and internalin B but requires cytoskeletal motion and factors present in human plasma. A major portion of internalized bacteria is found in membrane-bound phagosomes and is rarely free in the cytosol, as shown by transmission electron microscopy and by using an L. monocytogenes strain expressing green fluorescent protein when in the host cell cytosol. The infection caused maturation of the immature DCs into mature DCs displaying high levels of CD83, CD25, major histocompatibility complex class II, and the CD86 costimulator molecule. This effect appeared to be largely mediated by listerial lipoteichoic acid. Although L. monocytogenes infection is known to induce death in other cell types, infection of human DCs was found to induce necrotic but not apoptotic death in fewer than 20% of DCs. Therefore, the ability of DCs to act as effective antigen-presenting cells for listerial immunity is probably enhanced by their resistance to cell death, as well as their ability to rapidly differentiate into mature, immunostimulatory DCs upon encountering bacteria. 相似文献