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41.
For the clarification of pathogenesis and clinical relevance of decreases of the triiodothyronine (T3) level in patients with chronic inflammatory rheumatism in a group of 63 patients with clinically, paraclinically and roentgenologically diagnosed rheumatoid arthritis (59 times) and with SLE (4 times), respectively, parallel were determined parameters of the thyroid gland function and of the rheumatic activity as well as a subtile drug anamnesis for the medication of antirheumatic drugs was established. In 33 of the 63 patients who were included into the study decreases and low normal values, respectively, for the total T3 (TT3 less than 1.5 nmol/l) were found. In comparison to the remaining 30 patients with normal TT3 a typical constellation of paraclinical parameters of the thyroid gland with distinct reduction of TT3 and free T3 (FT3), low normal total T4 (TT4), slight increase of the reverse T3 (rT3), moderate decrease of the basal and stimulated TSH and an only very small restriction of the binding capacity of the thyroid hormone (TBG) were found. A clinically relevant hypothyroidism is thus to be excluded with certainty. Antirheumatic drugs, in particular steroidal ones (glucocorticoids) may on principle also induce such paraclinical constellations, related to the thyroid gland. In our investigations a therapy with antirheumatic drugs is causally scarcely considered, since both in the group of patients with decrease of T3 and without decrease comparable quantities of antirheumatic drugs including glucocorticoids were administered and the cortisol values in the plasma do not differ. The investigations confirm our already formerly expressed supposition that also in rheumatics a "low-T3-syndrome" is existing as it is otherwise described in consumptive extrathyroidal diseases (NTI).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
42.
The ability of a purified major histocompatibility antigen to serve as the target cell antigen for alloreactive CTL (H-2d anti-H-2k) was examined. Tumor cells syngeneic with responding CTL were used as targets following modification with purified alloantigen (H-2Kk). A short incubation of tumor cells with H-2Kk liposomes followed by the addition of polyethylene glycol (PEG) yielded modified tumor cells that were recognized and lysed by CTL. The macrophage-like cell line P388D1 was readily recognized following liposome and PEG modification; apparently because these cells can withstand PEG mediated insertion of H-2Kk and lipid into their membrane. The generation of targets by PEG mediated modification was most efficient using liposomes prepared with an H-2Kk:lipid ratio of about 1:500. H-2Kk containing liposomes prepared with negatively charged phospholipids readily attached to P388D1 cells, however these cells were not targets for CTL unless PEG was added. The specificity of CTL recognition and lysis of liposome modified cells was shown by the reactivity of CTL primed against alloantigens other than H-2Kk and by antibody (anti-H-2Kk) blocking of recognition and lysis. These results demonstrate that purified H-2Kk can serve as the alloantigen for CTL lysis and suggest that the H-2 must be oriented in the target cell lipid bilayer to serve as the alloantigen for CTL mediated target cell lysis.  相似文献   
43.
Distinction of high-grade esthesioneuroblastomas from other poorly differentiated tumors arising in the nasal cavity is an important diagnostic challenge because it determines patient management and prognosis. The human achaete-scute homologue (hASH1) gene is critical in olfactory neuronal differentiation and is expressed in immature olfactory cells; therefore, it could have potential use as a diagnostic marker The aim of the present study was to determine the value of hASH1 messenger RNA (mRNA) levels in differentiating esthesioneuroblastoma from other poorly differentiated tumors. A real-time polymerase chain reaction assay was developed, permitting the comparative determination of hASH1 mRNA levels in triplicate in a double-blind pilot study including 24 frozen cases of esthesioneuroblastoma and poorly differentiated tumors. All 4 positive cases were esthesioneuroblastomas, and all 19 poorly differentiated tumors were negative. In addition, there was an inverse association between the grade of esthesioneuroblastomas and hASH1 mRNA levels. The hASH1 mRNA level might represent a useful tool for distinguishing esthesioneuroblastoma from poorly differentiated tumors of the sinonasal region.  相似文献   
44.
Allicin, a major ingredient of fresh garlic extract that is produced during the crushing of garlic cloves, exerts various beneficial biological effects, including a broad spectrum of antimicrobial activity, antihyperlipidaemic and antihypertensive effects. However, how allicin affects the immune system is less well known, and its effect on human T cells has never been studied. Here, we examined the in-vitro effects of allicin on the functioning of T cells related to their entry to inflamed extravascular sites. We found that allicin (20-100 microm) inhibits the SDF-1alpha (CXCL12)-induced T cell migration through fibronectin (FN), and that this inhibition is mediated by the down-regulation of (i) the reorganization of cortical actin and the subsequent T cell polarization, and (ii) T cell adhesion to FN. Moreover, allicin also inhibited T cell adhesion to endothelial cells and transendothelial migration. The mechanisms underlying these inhibitory effects of allicin are associated with its ability to down-regulate the phosphorylation of Pyk2, an intracellular member of the focal adhesion kinases, and to reduce the expression of the VCAM-1- and FN-specific alpha4beta1-integrin (VLA-4). The ability of allicin to down-regulate these chemokine-induced and VLA-4-mediated T cell functions explains its beneficial biological effects in processes where T cells play an important role and suggests that allicin may be used therapeutically with chronic inflammatory diseases.  相似文献   
45.
The genetic transformation of plastids of higher plants has developed into a powerful approach for both basic research and biotechnology. Due to the high copy number of the plastid genome per plastid and per cell, repeated cycles of shoot regeneration under conditions selective for the modified plastid chromosome are required to obtain transformants entirely lacking wild-type plastid genomes. The presence of promiscuous plastid DNA in nuclear and/or mitochondrial genomes that generally contaminate even gradient-purified plastid fractions reduces the applicability of the highly sensitive PCR approach to monitor the absence of residual wild-type plastid chromosomes in transformed lines. It is therefore difficult, or even impossible, to assess reliably the hetero- or homoplastomic state of plastid transformants in this manner. By analysing wild-type and transplastomic mutants of tobacco, we demonstrate that separation of plastid chromosomes isolated from gradient-purified plastid fractions by pulsed-field gel electrophoresis can overcome the problem of (co)amplification of interfering promiscuous plastid DNA. PCR analyses with primers specific for plastid, mitochondrial and nuclear genes reveal an impressive purity of such plastid DNA fractions at a detection limit of less than one wild-type plastid chromosome copy per ten transplastomic cells.  相似文献   
46.
Human recombinant neutralizing antibodies against hantaan virus G2 protein   总被引:13,自引:0,他引:13  
Koch J  Liang M  Queitsch I  Kraus AA  Bautz EK 《Virology》2003,308(1):64-73
Old world hantaviruses, causing hemorrhagic fever with renal syndrome (HFRS), still present a public health problem in Asia and Eastern Europe. The majority of cases has been recorded in China. The aim of our study was to generate human recombinant neutralizing antibodies to a hantavirus by phage display technology. To preserve the structural identity of viral protein, the panning procedure was performed on native Hantaan (HTN) (76-118) virus propagated in Vero-E6 cells. In total, five complete human recombinant IgG antibodies were produced in a baculovirus expression system. All of them were able to completely neutralize HTN, and Seoul (SEO) virus in a plaque reduction neutralization test (PRNT). Three of these antibodies could also completely neutralize Dobrava (DOB) virus but not Puumala (PUU) virus. All antibodies bind to Hantaan virus G2 protein localized in the virus envelope. The sequence areas within the HTN (76-118)-G2 protein detected by five selected antibodies were mapped using peptide scans. Two partial epitopes, 916-KVMATIDSF-924 and 954-LVTKDIDFD-963, were recognized, which presumably are of paramount importance for docking of the virus to host cell receptors. A consensus motif 916-KVXATIXSF-924 could be identified by mutational analysis. The neutralizing antibodies to the most widely distributed hantaviruses causing HFRS might be promising candidates for the development of an agent for prevention and treatment of HFRS in patients.  相似文献   
47.
48.
Myeloperoxidase (MPO) is an oxidative enzyme expressed in polymorphonuclear leukocytes. It is involved in the defence against periodontal bacteria, and is also able to mediate inflammatory tissue destruction in periodontal disease. A G/A polymorphism in the promoter region of the MPO gene at position -463 has been assumed to exert profound effects on the expression of the enzyme. It is the aim of this study to evaluate whether this polymorphism may influence the risk of periodontal diseases. A total of 3148 subjects were randomly selected from the general population in the SHIP study (Study of Health in Pomerania). Periodontal status, health-related and socio-economic items were assessed. All subjects aged 40-60 years (n = 1103) were included in this study, and 1083 genotyped for the MPO -463 G/A polymorphism by PCR and RFLP methods. The genotype frequencies determined were homozygous wild type G/G 65.9% (95% CI 63.5-68.6), heterozygous A/G 31.4% (28.8-34.4), and homozygous variant A/A 2.7% (2.0-3.8). Only female subjects have a significantly reduced risk of severe periodontal disease when bearing the variant genotypes A/G or A/A. In female subjects the reduction in periodontal risk was significant for non-smokers (OR = 0.48; 95% CI 0.23-0.96); the smoke-related increase in risk was also reduced (OR = 0.50; 95% CI 0.22-1.10). When adjusted for age, smoking, and education the odds ratios were calculated as 0.52 (P = 0.01) and 0.97 (P = 0.90) for female and male subjects, respectively. The results of this study confirm the assumption that the MPO -463A allele variants are protective in the pathogenesis of periodontal diseases. This holds true only with women but not with men. The results are discussed with respect to the known influences of sexual hormones on MPO activity.  相似文献   
49.
The P300-amplitude evoked with an acoustic oddball-paradigm is considered the most stable late event-related potential (ERP). This amplitude-index has become a standard parameter in electrophysiology. Recently, a robust ERP-parameter (NoGo-anteriorization, NGA) has been introduced, which reflects spatial brain electrical changes in relation to execution and inhibition of a motor response elicited with a Continuous Performance Test (CPT). The current study refers to the stability of this new topographical ERP-parameter compared to the stability of the classical P300-amplitude. For that purpose, 12 healthy subjects were investigated with both paradigms during recording of a 21-channel EEG. Analysis of the resulting ERPs revealed a very high stability for both, topographical and amplitude index: In every single subject, the brain electrical fields were characterized by a more anterior location in the NoGo- compared to the Go-condition (=NGA) and by higher amplitudes after target compared to distractor condition. T-tests, analyses of the effect size and of the power revealed equivalent differences between the two contrasting conditions for the topographical compared to the amplitude index. These results indicate that the stability of the topographical ERP-parameters elicited with the CPT is sufficient for an electrophysiological standard-index. The possibility to elicit a robust and specific spatial brain activation with the CPT is an ideal completion to the classical P300 amplitude effect and, therefore, hopefully will be a useful expansion of the standard paradigms in electrophysiological laboratories.  相似文献   
50.
A conventional nested PCR and a real-time LightCycler PCR assay for detection of Coccidioides posadasii DNA were designed and tested in 120 clinical strains. These had been isolated from 114 patients within 10 years in Monterrey, Nuevo Leon, Mexico, known to be endemic for coccidioidomycosis. The gene encoding the specific antigen 2/proline-rich antigen (Ag2/PRA) was used as a target. All strains were correctly identified, whereas DNA from related members of the family Onygenaceae remained negative. Melting curve analysis by LightCycler and sequencing of the 526-bp product of the first PCR demonstrated either 100% identity to the GenBank sequence of the Silveira strain, now known to be C. posadasii (accession number AF013256), or a single silent mutation at position 1228. Length determination of two microsatellite-containing loci (GAC and 621) identified all 120 isolates as C. posadasii. Specific DNA was amplified by conventional nested PCR from three microscopically spherule-positive paraffin-embedded tissue samples, whereas 20 human tissue samples positive for other dimorphic fungi remained negative. Additionally, the safety of each step of a modified commercially available DNA extraction procedure was evaluated by using 10 strains. At least three steps of the protocol were demonstrated to sufficiently kill arthroconidia. This safe procedure is applicable to cultures and to clinical specimens.  相似文献   
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