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11.
Five cases of non-molar trophoblastic disease including one placental site trophoblastic tumor (PSTT), two exaggerated placental sites and two choriocarcinomas were compared with each other and with normal chorionic villi and placental site. This involved light microscopic, immunohistochemical and ultrastructural studies. Comparison of PSTT with choriocarcinoma suggested that the former represented a neoplastic transformation of placental site intermediate trophoblast. The PSTT showed a characteristic immunohistochemical distribution of human placental lactogen and human chorionic gonadotropin, resembling that of the placental site intermediate trophoblast. Placental site trophoblastic tumor cells were also characterized ultrastructurally by prominent perinuclear filaments, abundant rough endoplasmic reticulum, or both. Infiltrating intermediate trophoblasts in exaggerated placental sites were similar to PSTT cells rather than normal placental site intermediate trophoblasts. However cells with vacuolated cytoplasm or spindle-shaped intermediate trophoblastic ceils were observed more frequently in the PSTT than the exaggerated placental sites. The intermediate trophoblastic cells in the choriocarcinomas showed a morphologically transitional form from cytotrophoblastic cell to syncytiotrophoblastic cell, but did not share unique ultra-structural similarities with placental site intermediate trophoblasts.  相似文献   
12.
A reliable and reproducible immunofluorescence method is described for the detection of anti-cytoskeleton antibodies in human sera, based on the use of vinblastine-treated peripheral blood mononuclear cells as substrate. Three immunofluorescence patterns associated with antibodies to microfilaments, intermediate filaments and microtubules are readily identified.  相似文献   
13.
The expression of intermediate filament proteins in human endometrial tissue was examined. Desmin was selectively expressed in decidualized stroma, as demonstrated by SDS-PAGE analysis and positive response with a monoclonal antibody specific for desmin in ELISA and in western blot analysis. The same monoclonal antibody specifically stained human decidual cells in decidualized endometrium (secretory endometrium) in formalin-fixed paraffin-embedded sections prepared from diagnostic curettage samples. Desmin was also detected in menstrual fluid. Therefore, desmin might serve as a biochemical and histochemical marker of human decidualized endometrium.  相似文献   
14.
Liver infiltrating lymphocytes (LIL) were isolated from HCV-positive (+) and HCV-negative (–) end-stage livers. Phenotypic analysis and functional studies using proliferative and lymphocytotoxic assays were performed with the isolated LIL. Two CD3+ lymphocyte populations were found in LIL using FITC anti-CD3 monoclonal antibodies (mAb). One was a bright fluorescence intensity population (as in PBL), and the other dim. We calculated the number of FITC-anti-CD3 mAbs bound per lymphocyte on PBL and LIL and found 80,040 ± 4628 and 39,615 ± 3932, respectively. Therefore, HCV+ and HCV– patient PBL contained approximately twice the number of CD3 molecules per cell than patient CD3+ LIL. LIL also contained approximately a threefold higher concentration of TCR+, CD4–CD8–, and CD56,16 (NK) cells than the patient PBL. Thus, a major subset of LIL is phenotypically similar to mouse NK1.1+ intermediate T cells. LIL freshly isolated from HCV+ livers exhibited weak CTL activity against EBV- or Con A-transformed lymphoblast targets infected with vaccinia–HCV recombinant virus (rHCV) or primary hepatocyte cultured cells. However, after in vitro coculture of LIL with rHCV, these cells developed a strong cytotoxicity for the above targets. In contrast, LIL from HCV– livers were not cytotoxic against the same targets. Histochemical studies (in situ) demonstrated that these hepatocytes express CD95, and stains demonstrated apoptosis. The HCV+ hepatocytes also express class I MHC molecules and ICAM-1. The addition of mAb specific for these adhesion molecules inhibited CML activity. Short-term cultured hepatocytes (targets) from HCV+ and HCV– patients produced low levels of cytokines IL-1, IL-2, IL-6, TNF, and IFN- but a high level of IL-8. It is speculated that LIL expressing reduced numbers of CD3 molecules may even function as immune regulators as proposed for intermediate T cells in mice.  相似文献   
15.
A case Is presented of intermediate lymphocytic lymphoma seen In a 53 year old mate, which extensively Infiltrated systemic organs, Including the entire digestive tract from the esophagus to the rectum. Payer's patch Invasion was evident. Multiple Intestinal perforations caused death 5 months later. Surface marker studies suggested the marginal zone origin for this CD2CT B cell malignancy.  相似文献   
16.
Summary When administered microelectrophoretically GABA and piperidine-4-sulphonic acid depolarized the central terminations of muscle group Ia and Ib afferent fibres in the lumbar intermediate nucleus and Clarke's column of cats anaesthetised with pentobarbitone sodium. Both this depolarization, and primary afferent depolarization, generated by impulses in other primary afferent fibres which produce prolonged bicuculline-sensitive inhibition of the firing of group I afferent fibre-excited interneurones in the intermediate nucleus and cells in Clarke's column, are reduced by microelectrophoretic bicuculline methochloride. Systemically administered (±)-baclofen hydrochloride (maximum dose 8 mg kg–1) depressed the monosynaptic excitation of Clarke's column neurones by impulses in muscle and cutaneous afferent fibres. Microelectrophoretically administered (–)-baclofen reduced the bicuculline-sensitive primary afferent depolarization of group I terminations without, however, reducing the depolarizing action of GABA or piperidine-4-sulphonic acid. The depression by (–)-baclofen of the group I monosynaptic excitation of intermediate nucleus neurones is not reduced by concentrations of bicuculline methochloride adequate to suppress prolonged inhibition of these neurones  相似文献   
17.
Desmin‐related myopathy is a familial or sporadic disease characterized by skeletal muscle weakness and cardiomyopathy as well as the presence of intracytoplasmic aggregates of desmin‐reactive material in the muscle cells. Previously, two kinds of deletions and eight missense mutations have been identified in the desmin gene and proven to be responsible for the disorder. The present study was conducted to determine structural and functional defects in a pathogenic desmin variant that caused a disabling disorder in an isolated case presenting with distal and proximal limb muscle weakness and cardiomyopathy. We identified a novel heterozygous Q389P desmin mutation located at the C‐terminal part of the rod domain as the causative mutation in this case. Transfection of desmin cDNA containing the patient’s mutation into C2.7, MCF7, and SW13 cells demonstrated that the Q389P mutant is incapable of constructing a functional intermediate filament network and has a dominant negative effect on filament formation. We conclude that Q389P mutation is the molecular event leading to the development of desmin‐related myopathy. Hum Mutat 18:388–396, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   
18.
Smooth muscle cells possess a structural lattice composed of two primary parts: the ‘cytoskeleton’ that pervades the cytoplasm and the ‘membrane skeleton’ that provides anchorage for the cytoskeleton and contractile apparatus at the cell surface. The cytoskeleton contains two major components: first, a complement of actin filaments that links the cytoplasmic dense bodies at equispaced intervals in longitudinal fibrils; and second, a network of desmin intermediate filaments that co-distributes with the cytoskeletal actin. The actin filaments of the contractile apparatus are presumed to interface with the cytoskeleton at the cytoplasmic dense bodies and with the longitudinal rib-like arrays of dense plaques of the membrane skeleton that couple to the extracellular matrix. The present report focuses attention on the functional role of intermediate filaments and on the molecular domain structure of the protein calponin, which is found both in the cytoskeleton and the contractile apparatus. New information about the role of intermediate filaments in smooth muscle has come from studies of transgenic mice in which desmin expression has been ablated. These have shown that while desmin is dispensable for normal development and viability its absence has significant consequences for the mechanical properties of muscle tissue. Thus, the visceral smooth muscles develop only 40% of the normal contractile force and the maximal shortening velocity is reduced by 25–40%. Intermediate filaments therefore play an active role in force transmission and do not contribute solely to cell shape maintenance, as has hitherto been presumed. Recent studies on calponin have revealed a second actin binding domain at the C-terminus of the molecule and have also pinpointed an N-terminal domain that shares homology with a growing family of actin binding and signalling molecules. How these newly identified features of calponin relate to its function in vivo remains to be established.  相似文献   
19.
Immunofluorescence studies on Epstein-Barr virus (EBV)-transformed lymphoblastoid cells have previously shown that the latent membrane transforming protein (LMP-1) is found in patch-like inclusions which also immunostain for vimentin. We now show that EBV transformation causes a major reorganization of intermediate filaments, microtubules, mitochondria, and lysosomal elements, which generally become oriented around the microtubule organizing centre. Immunogold electron microscopy shows that LMP-1 is primarily concentrated in secondary lysosomes together with ubiquitin-protein conjugates and heat-shock protein 70. Intermediate filament inclusion formation with the above characteristics may be a general response triggered by other membrane glycoproteins; as seen, for example, in major human neurodegenerative diseases such as diffuse Lewy body disease.  相似文献   
20.
The hunt for genes influencing behavior may be aided by the study of intermediate phenotypes for several reasons. First, intermediate phenotypes may be influenced by only a few genes, which facilitates their detection. Second, many intermediate phenotypes can be measured on a continuous quantitative scale and thus can be assessed in affected and unaffected individuals. Continuous measures increase the statistical power to detect genetic effects (Neale et al., 1994), and allow studies to be designed to collect data from informative subjects such as extreme concordant or discordant pairs. Intermediate phenotypes for discrete traits, such as psychiatric disorders, can be neurotransmitter levels, brain function, or structure. In this paper we conduct a multivariate analysis of data from 111 twin pairs and 34 additional siblings on cerebellar volume, intracranial space, and body height. The analysis is carried out on the raw data and specifies a model for the mean and the covariance structure. Results suggest that cerebellar volume and intracranial space vary with age and sex. Brain volumes tend to decrease slightly with age, and males generally have a larger brain volume than females. The remaining phenotypic variance of cerebellar volume is largely genetic (88%). These genetic factors partly overlap with the genetic factors that explain variance in intracranial space and body height. The applied method is presented as a general approach for the analysis of intermediate phenotypes in which the effects of correlated variables on the observed scores are modeled through multivariate analysis.  相似文献   
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