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101.
CD34(+) fibrocytes in normal cervical stroma,cervical intraepithelial neoplasia III,and invasive squamous cell carcinoma of the cervix uteri 总被引:3,自引:0,他引:3
Barth PJ Ramaswamy A Moll R 《Virchows Archiv : an international journal of pathology》2002,441(6):564-568
CD34(+) fibrocytes are widely distributed in normal connective tissues but have been reported to be absent within the stroma associated with invasive carcinomas. In the present study we investigated the presence and distribution of CD34(+) fibrocytes and alpha-smooth muscle actin (alpha-SMA) positive myofibroblasts in cervical intraepithelial neoplasia III (CIN III; n=8), invasive carcinoma of the cervix ( n=18) and adjacent normal cervical stroma. Normal cervical stroma and the stroma adjacent to CIN III disclosed a dense network of CD34(+) fibrocytes, whereas the stroma of invasive carcinoma was virtually free of this cell population. Early stromal invasion by squamous carcinoma was characterized by a focal loss of CD34(+) fibrocytes. alpha-SMA-positive myofibroblasts were not seen in the normal cervical stroma but occurred in six of eight cases of CIN III adjacent to the atypical epithelium. The stroma of invasive carcinoma was made up of large amounts of haphazardly arranged alpha-SMA-positive myofibroblasts. In the setting of the present study, a loss of CD34(+) fibrocytes was specific for stromal alterations associated with invasive carcinoma and proved to be a sensitive tool in detecting small foci of stromal invasion. Therefore, detection of a loss of CD34(+) fibrocytes may constitute an adjunctive tool in detecting (1) early stromal invasion and (2) invasive carcinoma in small biopsy specimens. Moreover, the present study shows that CD34(+) fibrocytes and myofibroblasts play an important role in stromal remodeling associated with invasive squamous cell carcinoma of the cervix. 相似文献
102.
Zelazny AM Ferraro MJ Glennen A Hindler JF Mann LM Munro S Murray PR Reller LB Tenover FC Jorgensen JH 《Journal of clinical microbiology》2005,43(6):2613-2615
A nine-laboratory collaborative study was conducted to select positive and negative quality assessment control strains for the detection of inducible clindamycin resistance in staphylococci. Four strains of Staphylococcus aureus were tested as unknowns on 10 different days in each laboratory using the recently recommended CLSI (formerly NCCLS) disk diffusion method and the inoculum purity control method. Strains contained either macrolide-lincosamide-streptogramin B (MLSB) resistance genes encoded by erm(A) or erm(C) or a macrolide resistance efflux pump encoded by msr(A). Based upon the results of this study, strain UT 32 (now designated ATCC strain BAA-977) containing erm(A) is recommended as the positive control organism for inducible clindamycin resistance. Strain UT 25 (now designated ATCC BAA-976), which harbors the efflux pump encoded by msr(A), is recommended as the negative control organism. 相似文献
103.
Differential expression of beta 1 integrins in nonneoplastic smooth and striated muscle cells and in tumors derived from these cells. 总被引:1,自引:1,他引:1
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G. Mechtersheimer T. Barth A. Quentmeier P. Mller 《The American journal of pathology》1994,144(6):1172-1182
Integrins are a superfamily of transmembrane alpha beta heterodimers that play an important role in cell-matrix and cell-cell interactions by acting as receptors for extracellular matrix proteins and for cell adhesion molecules. Using monoclonal antibodies against beta 1, alpha 1 to alpha 6, and alpha v subunits, the in situ distribution pattern of beta 1 integrins was examined immunohistochemically in nonneoplastic smooth and striated muscle cells and in their tumors. Nonneoplastic smooth muscle cells were beta 1+, alpha 1+, alpha 3+, alpha v+ and, in diverse localizations, also alpha 5+ or even alpha 6+. The expression of the beta 1 chain was conserved in all leiomyomas and leiomyosarcomas. The distribution pattern of the alpha subunits by contrast underwent several changes during malignant transformation of smooth muscle cells. These alterations consisted in a neoexpression of alpha 2, alpha 4, and alpha 6 as well as in an abnormal abrogation of alpha 1 and alpha 3 in some leiomyosarcomas. Except for the absence of alpha 5 in the majority of epithelioid leiomyosarcomas, expression of the alpha 5 and alpha v subunits was mainly conserved. In addition, tumors with epithelioid differentiation differed from typical cases by the absence of alpha 1 and the simultaneous presence of alpha 4. Adult striated muscle cells were beta 1+ but alpha 1- to alpha 6- and alpha v-, whereas fetal striated muscle cells were not only beta 1+ but also alpha 3+/-, alpha 4+/-, alpha 5+ and alpha 6+. In all rhabdomyosarcomas the expression of beta 1 was retained. Furthermore, the majority of cases showed the expression of one or more alpha subunits most of which, ie, alpha 4, alpha 5, and alpha 6, were also found in fetal striated muscle cells. In conclusion, beta 1 integrins exhibited a differential expression pattern along the two lines of myogenic differentiation. This integrin profile underwent characteristic changes during malignant transformation. Nevertheless, the compiled distribution patterns of the alpha 1, alpha 3, and alpha v subunits allowed in most instances the discrimination between tumors of smooth (alpha 1+/alpha 3+/alpha v+) and striated muscle (alpha 1-/alpha 3-/alpha v-) differentiation. 相似文献
104.
Barth TF Leithäuser F Döhner H Bentz M Pawlita M Schmid U Möller P 《Virchows Archiv : an international journal of pathology》2000,436(4):357-364
In contrast to primary gastric lymphomas of B-cell type, little is known about primary gastric T-cell lymphomas. We describe
three cases with remarkably similar features: diffuse growth, epitheliotropism, medium too large cell size, high apoptotic
rates, and a CD3+, CD4+, CD8+, CD45RO+ immunophenotype. Clonal TCRγ gene rearrangement was shown in two cases. Epstein-Barr
virus infection was excluded in two cases. Taking advantage of fresh-frozen material, we analyzed two cases further, revealing
CD5–, CD16+, CD56–, CD57–, CD25+, CD30+, CD103 (αEβ7)+, bcl-2 protein+, CD95+, CD95 ligand(L)–. CD95L, however, was detected
in histiocytic and fibroblastoid by stander cells. The lymphomas expressed granzyme B, perforin, and the TIA-1 antigen in
various combinations. All three cases had a very unfavorable clinical course characterized by local recurrence and/or dissemination
to other epithelial sites, leading to death within 6–12 months after the initial diagnosis despite surgery and aggressive
antineoplastic treatment. These data suggest a novel variant of peripheral T-cell lymphoma operationally characterized as
primary gastric, apoptosis-rich, CD103+, EBV-, T-cell lymphoma co-expressing CD4, CD8, CD16 and cytotoxic molecules.
Received: 20 August 1999 / Accepted: 2 November 1999 相似文献
105.
Recombinant troponin I substitution and calcium responsiveness in skinned cardiac muscle 总被引:1,自引:0,他引:1
John D. Strauss Jennifer E. Van Eyk Zacharias Barth Lan Kluwe Rudolf J. Wiesner K. Maéda J. Caspar Rüegg 《Pflügers Archiv : European journal of physiology》1996,431(6):853-862
Using treatment with vanadate solutions, we extracted native cardiac troponin I and troponin C (cTnI and cTnC) from skinned
fibers of porcine right ventricles. These proteins were replaced by exogenously supplied TnI and TnC isoforms, thereby restoring
Ca2+-dependent regulation. Force then depended on the negative logarithm of Ca2+ concentration (pCa) in a sigmoidal manner, the pCa for 50% force development, pCa50, being about 5.5. For reconstitution we used fast-twitch rabbit skeletal muscle TnI and TnC (sTnI and sTnC), bovine cTnI
and cTnC or recombinant sTnIs that were altered by site-directed mutagenesis. Incubation with TnI inhibited isometric tension
in TnI-extracted fibers in the absence of Ca2+, but restoration of Ca2+ dependence required incubation with both TnI and TnC. Relaxation at low Ca2+ levels and the steepness of the force/pCa relation depended on the concentration of exogenously supplied TnI in the reconstitution
solution (range 20–150 μM), while Ca2+ sensitivity, i.e. the pCa50, was dependent on the isoform, and also on the concentration of TnC in the reconstitution solution. At pH 6.7, skinned fibers
reconstituted with optimal concentrations of sTnC and sTnI (120 μM and 150 μM, respectively) were more sensitive to Ca2+ than those reconstituted with cTnC and cTnI (difference in pCa50 approx. 0.2 units). Rabbit sTnI was cloned and expressed in Escherichia coli using a high yield expression plasmid. We introduced point mutations into the TnI inhibitory region comprising the sequence
of the minimal common TnC/actin binding site (-G104-K-F-K-R-P-P-L-R-R-V-R115-). The four mutants produced by substitution of T for P110, G for P110, G for L111, and G for K105 were chosen, based on previous work with synthetic peptides showing that single amino acid substitution in this region diminished
the capacity of these peptides to inhibit acto-S1 ATPase or contraction of skinned fibers. Therefore, all amino acid residues of the inhibitory region are thought to contribute
to biological activity of TnI. However, each of the recombinant TnIs could substitute for endogenous TnI. In combination with
exogenous TnC, Ca2+ dependence could be restored when gly110sTnI, thr110sTnI or gly111sTnI was used for reconstitution. The mutant gly105sTnI, on the other hand, reduced the ability of skinned fibers to relax at low Ca2+ concentrations and it caused an increase in Ca2+ sensitivity.
Received: 5 October 1995/Received after revision and accepted: 1 December 1995 相似文献
106.
The specificity of the αβ T cell receptor for class I or class II major histocompatibility complex (MHC) molecules determines whether a mature T cell will be of the CD4?CD8+ or CD4+CD8? phenotype, respectively. We show here that a human CD4 transgene can rescue a significant fraction of CD4?CD8+ T cells in β2-microglobulin-deficient mice. Cells with this phenotype could be induced to become potent killers of targets expressing allogeneic MHC antigens, indicating that lineage commitment can precede the rescue of developing cells by the T cell receptor for antigen and the CD4 coreceptor. 相似文献
107.
108.
Prof. H. Hofmann Dr. C. Bothge Dr. S. Haselwarter Prof. L. Heinemann Dr. W. Barth Dr. E. Schüler Prof. U. Laaser Dr. M. Siegel Prof. F. C. Luft Die Intersalt-Forschungsgruppe aus BRD und DDR 《Journal of molecular medicine (Berlin, Germany)》1990,68(13):655-663
Summary The relationships between body mass index (BMI) and age, alcohol consumption, 24-hr urinary electrolyte excretion, and BP were studied in 588 subjects from three German centers participating inIntersalt, a highly standardized, previously reported protocol. Men and women aged 20–59 were sampled in Bernried, FRG; Cottbus, GDR; and Heidelberg, FRG. The subjects from the three centers did not differ in BMI, level of education, physical activity, cigarette- or alcohol-consumption patterns, or urinary Cl excretion. Mean Na excretion was 167, 147, and 172 mmol/24 hr in Bernried, Cottbus, and Heidelberg, while mean K excretion was 72, 55, and 73 mmol/24 hr, respectively. The excretion of these electrolytes was significantly lower in Cottbus than in Bernried or Heidelberg. BMI increased progressively in men with age; in women BMI plateaued until the 5th decade, after which it increased to equal that of men. In individual centers, the excretion of electrolytes was correlated with BML Sodium and chloride excretion were highly correlated. The data from each individual center were fitted to a multiple regression model. Age, BMI, sex, and alcohol consumption entered the model. 相似文献
109.
Wolf-Gerald Hiller Harald Pasch Irene V. Lampe 《Macromolecular chemistry and physics.》1991,192(10):2487-2495
Copolymers of 4-chlorophenyl methacrylate and methyl methacrylate were prepared and investigated by 1H and 13C NMR spectroscopy. The copolymer composition, determined by chlorine analysis, 1H and 13C NMR, was found to be close to the initial composition of the monomer mixture. The sequence analysis was carried out by analyzing the methoxy signals of the 1H NMR spectra. Six out of ten tactic and compositional triads could be resolved. It was found that the copolymers are predominantly syndiotactic and the compositional and tactic triad populations are given. The aromatic carbon atoms are sensitive towards compositional and tactic sequence effects, which results in a switch of the order of the tactic signals at different aromatic carbon atoms. 相似文献
110.
Capsaicin-sensitive non-cholinergic excitatory innervation of the guinea-pig tracheobronchial smooth muscle 总被引:11,自引:0,他引:11
Field stimulation of the isolated main bronchi of the guinea-pig results in a rapid contraction followed by a sustained contractile response. Tetrodotoxin abolished these effects. The first phase was strongly inhibited by hyoscine, indicating that it was mediated mainly by excitation of cholinergic nerves. The lasting contraction was abolished by capsaicin tachyphylaxis but it was resistant to the effects of hyoscine, hexamethonium or physostigmine. It is suggested that capsaicin-sensitive non-cholinergic nerves have major excitatory effect on the guinea-pig bronchial smooth muscle and there is also evidence for their influence on the trachea. 相似文献