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1.
Summary Immunohistochemical localization of S-100 protein, its and subunits, and glial fibrillary acidic protein (GFAP) in normal and neoplastic salivary glands was studied by the peroxidase-antiperoxidase method and immunoblot analysis. Positive immunostaining for S-100 protein was observed in pleomorphic adenoma, adenolymphoma, tubular adenoma, adenoid cystic carcinoma, acinic cell tumour, adenocarcinoma and carcinoma in pleomorphic adenoma. S-100 protein was localized in myoepithelial cells, epithelial cells of intercalated ducts and serous acinar cells of normal salivary gland. Both and subunits of S-100 protein showed almost identical distribution in normal and neoplastic salivary glands, but skeletal muscle cells were -positive/-negative whereas Schwann cells and fat cells were -negative/-positive in the stroma and neighbouring tissue. GFAP was only found in pleomorphic adenoma and its malignant counterpart. Immunoblot analysis showed that the GFAP-related antigen consisted of several polypeptide bands with a molecular weight ranging between 35,000 to 50,000 daltons.  相似文献   

2.
The S-100 cells in the pituitary glands of adult male Sprague Dawley rats (SDs) and spontaneous dwarf rats (SDRs) were immunohistochemically examined using anti-S-100 and anti-S-100 monoclonal antibodies. The immunoreactive cells against S-100 protein were divided into three subtypes on the basis of their immunore-activity against subunits of S-100 protein: S-100 dominant type (the -type cell), S-100 dominant type (the \-type cell) and immunoreactive against both S-100 and S-100 (the -type cell). In the SD, -type cells represented 26% of the total S-100 immunoreactive cells (S-100 cells) and were localized in the peripheral area of the ventral region of the pituitary gland. This type of cell was observed forming clusters, with more abundant cytoplasm than the -type cell. The proportion of -type cells was 53%. They were diffusely distributed throughout the gland, and their processes were thicker than those of the -type cell. In the SDR, the proportion of -type cells was 55%, and they were observed throughout the gland. In contrast, -type cells totalled 12% and were localized in small areas of the central and peripheral region of the gland. The proportion of -type cells was 21% in the SD and 33% in the SDR and they were observed forming small clusters in both animal groups. The proportion of -type cells compared with the total of S-100-immunoreactive cells was significantly higher (P < 0.05) in the SDR than in the SD, while the proportion of -type cells was markedly lower (P < 0.05).  相似文献   

3.
Effects of G protein subunits from rat brain on cardiac K+ channel was examined in single atrial cells of guinea-pig, using patch clamp techniques. We found that 10 pM concentration of rat brain subunits preparation could activate the atrial muscarine receptor-gated K+ channel (IK.ACh). Neither the detergent, CHAPS, used to suspend nor the boiled preparation activated IK.ACh. Furthermore, preincubation of subunits preparation in Mg2+-free solution, which easily inactivated -GTP-S, did not affect -activation of IK.ACh. We concluded, therefore, that subunits themselves can activate IK.ACh.Supported by the grants from the Ministry of Education, Culture and Science of Japan and from the Calcium Signal Workshop on Cardiovascular Systems  相似文献   

4.
Summary This immunohistochemical study disclosed that 9 of 15 GH secreting pituitary adenomas contained subunit positive cells. These cases also contained PRL positive adenoma cells, but LH was negative. Of these 9 cases, 4 cases showed occasional FSH containing cells, 2 of these also contained a few TSH positive cells. By mirror section technique, variable numbers of adenoma cells were found to contain both GH and subunit. Immunoelectron microscopically, both GH and subunit were localized in secretory granules which suggested their co-release from the tumour cells. The presence of GH and subunit in rough endoplasmic reticulum indicated their active production in the tumour. In the normal adult anterior pituitary gland, about 10% of GH cells contain FSH , and LH subunits and had appearances suggesting the co-production of GH and FSH as well as LH. The colocalization of GH and FSH is considered to be associated with the neoplastic transformation GH cells which possess the intrinsic potentiality of differentiation toward subunit. However, the mechanism for the lack or deficiency of subunits in the neoplastic condition remains to be further investigated.  相似文献   

5.
Summary The purpose of this study was to ascertain whether the pituitary-adrenal responses to human corticotropin-releasing hormone (hCRH) in non-functioning adrenocortical adenoma would uncover a functional activity in these adrenal nodules. Eleven patients with incidentally discovered silent adrenocortical adenoma and eleven controls were studied. The initial clinical and laboratory examination, including an overnight 1 mg dexamethasone suppression test, revealed no abnormalities in any of the subjects. IR-ACTH and serum steroids (F, S, P, 17OHP, 18OHB, and aldosterone) were normal in both controls and patients. After pulse IV injection of 100 g hCRH, the cortisol response was significantly exaggerated (P=0.01). Stimulated plasma ACTH levels were, however, significantly lower in patients than in controls (P=0.01), indicating counter-feedback regulation of cortisol. The peak cortisol/peak ACTH ratio (Fmax/ACTHmax) in the patients was significantly elevated (26.8±4.37 nmol/ng vs. 14.6±2.16 nmol/ ng,P=0.02). Two further patients with incidentally discovered pre-Cushing's adrenocortical adenoma displayed an even higher ratio (43.5 and 45.5 nmol/ng). In established Cushing's syndrome due to an autonomous adrenocortical adenoma, suppression of ACTH and of the ACTH response to hCRH occurs with a very high basal cortisol/ basal ACTH ratio. Our findings suggest some functional activity even in clinically silent adrenocortical adenoma. Response to hCRH uncovers a continuous spectrum between adrenocortical adenoma, pre-Cushing's, and Cushing's syndrome.Abbreviations ACA adrenocortical adenoma - ACTH adrenocorticotropin - DHEAS Dehydroepiandrosterone sulfate - F cortisol - hCRH human corticotropin releasing hormone - P progesterone - S 11-deoxycortisol - 17OHP 17-hydroxyprogesterone - 18OHB 18-hydroxy-corticosterone  相似文献   

6.
Summary Ten FSH producing pituitary adenomas were studied immunohistochemically. 9 cases were in males, and 7 showed elevated serum FSH levels. Immunohistochemically, all cases showed the presence of -subunit and FSH- subunits in many tumour cells. These two subunits were frequently colocalized in the same cells. However, the expression of LH- subunit was extremely low (1 of 10 cases exhibiting occasional LH- positive tumour cells), although it has been reported that FSH- and LH- subunits are colocalized in the same cells of the normal adult pituitary gland. Immunoelectron microscopically, -subunits and FSH- were present in the secretory granules and suggested the co-release of subunits or secretion of combined form of FSH. In 7 cases, TSH- was positive, and in some cases, TSH- was colocalized in the same tumour cells which contained -subunit and FSH- subunit. A few cases also demonstrated immunoreactivity for PRL and ACTH. Our immunohistochemical studies suggest that FSH adenomas are multihormonal and that there is abnormal gene expression in FSH cells with loss of LH- appearance and co-expression of TSH-.  相似文献   

7.
Activation of vascular-adrenergic receptors prevents an increase in vascular permeability caused by free radicals or inflammatory peptides. Methylxanthines seem to have similar protective effects on vascular endothelium. In the present study we investigated the effect of theophylline on the-adrenergic receptor expression and cAMP concentrations in cultured endothelial and smooth muscle cells from bovine aorta. Comparable values for-receptor density and binding affinity were detected in both cell types. Isoproterenol induced significant downregulation of-receptors in endothelial (BAEC: –60.5%) and smooth muscle cells (BASMC: –52.5%; P < 0.01). Incubation of endothelial cells with theophylline (4 µg/ml and 40 µg/ml) for 24 hours did not affect-receptor expression, whereas in smooth muscle cells the-receptor density was reduced for –31.5% and –28.7, respectively. In endothelial cells a transient effect on cAMP concentrations was observed after stimulation with isoproterenol (1 µM), but no effect was found in theophylline treated endothelial cells. Stimulation of intact smooth muscle cells with isoproterenol and theophylline (4 µg/ml and 40 µg/ml) resulted in a significant increase of cAMP concentrations after 60 and 240 minutes. The present data suggest a novel, celltype specific effect of theophylline on the-adrenergic receptor expression in vascular smooth muscle cells in vitro.  相似文献   

8.
We studied adhesive properties and physiological activity in vivo of cells from Lewis lung carcinoma and its metastases. These cells differed in tumorogenic activity and metastatic potential in the syngeneic system. In vivo non-metastasizing cells are characterized by a lower content of surface lectins to tetrasaccharides SiaLex [Neu5Ac2-3Gal1-4(Fuc1-3) GlcNAc] and SiaLea [Neu5Ac2-3Gal1-3(Fuc1-4)GlcNAc] and trisaccharide HSO3Lex [HSO32-3Gal1-4(Fuc1-3)GlcNAc] compared to cells forming metastases in the syngeneic system. Metastatic cells with low tumorogenic activity weakly expressed lectins to disaccharide ligands 6-SiaLac [Neu5Ac2-6Gal1-4Glc], 6-HSO3LacNAc, and A-di [GalNAc 1-3Gal] and trisaccharides H-type 1 [Fuc1-2Gal1-3GlcNAc and Lex [Fuc1-3(Gal 1-4)GlcNAc] compared to cells that initiated tumor formation in the syngeneic system (similarly to transplanted tumors). We hypothesized that cell receptors to these carbohydrate determinates are involved in the development and growth of primary tumors, while lectins to SiaLex, SiaLea, and HSO3Lex play a role in the progress of tumor process and metastasizing.  相似文献   

9.
Zusammenfassung Bei Vorliegen einer normalen Diurese wird nach Ureterabklemmung der sog. hohe Ureterdruck, unter osmotischer Diurese der maximale erreicht. Die Differenz von Blutdruck und maximalem Ureterdruck war im Mittel der Versuche um 20 mm Hg kleiner als diejenige des hohen. Die Ursache dafür wird kurz diskutiert.Herrn Prof. Dr.S. Janssen zum 70. Geburtstag gewidmet.  相似文献   

10.
In eukaryotic cells, cAMP regulates many different cellular functions. Its effects are in most cases mediated by cAMP-dependent protein kinases. These consist of two regulatory and two catalytic subunits. In mammals, four different isoforms of cAMP-dependent protein kinases regulatory subunits have been characterized (RI and , RII and ). These four isoforms show a high level of homology and slightly different biochemical properties. In addition to biochemical properties, a different anatomical distribution of the regulatory isoforms may contribute to determine the specificity of diverse cAMP effects. By immunohistochemistry, the distribution of the detergent-insoluble fraction of RI isoform has been examined in rat and mouse brain. Biochemical fractionation shows that a large fraction of both RI and RI isoforms is bound to the cytoskeleton. RI labelling can be observed only in few locations: Purkinje cells, olfactory mitral cells, lateral thalamic neurons, superior olivary complex neurons. These cell populations are involved in the so called Purkinje cell degeneration. On the other hand, RI aggregates have a more widespread distribution, in brain areas involved in visceroemotional control. At the subcellular level, these two subunits show a different pattern of labelling: in most cells a sharply defined clustered labelling is observed for RI isoforms, while the RI isoform presents a weaker, diffuse intracytoplasmic distribution. Competition experiments point to the presence of, as yet unidentified, different and selective anchoring proteins for the two similar RI and isoforms. It is suggested that, as is the case for structural proteins, a different supramolecular organization of similar regulatory proteins may be crucial in order to fulfill different functions.  相似文献   

11.
Recombinant murine interferon (MuIFN-) given i.v. efficiently inhibited both pulmonary arrest and formation of lung colonies of NL-17, a highly metastatic variant of mouse colon adenocarcinoma 26. NL-17 was rather resistant to MuIFN- in vitro and was highly resistant to natural killer cells of mice even though they were treated in vivo with MuIFN-. Platelets isolated from MuIFN--treated mice showed reduced aggregating activity induced by NL-17. Since lung colonization by NL-17 is influenced by platelet aggregation, the inhibition of colonization by MuIFN- could be partly mediated through modification of platelet function in vivo. The effect of MuIFN- on platelet function and its subsequent inhibition of lung colony formation give new insights into the action of recombinant MuIFN-.  相似文献   

12.
Eighty-nine clinical isolates resistant (n=61) or susceptible (n=28) to imipenem and exhibiting the main patterns of susceptibility to other -lactam agents (wild type pattern, penicillinase pattern, constitutive cephalosporinase pattern) were studied in order to investigate (i) the mechanism of resistance involved and (ii) whether resistance to carbapenems affects the level of resistance to other -lactam agents and, conversely, if resistance to other -lactam agents affects the level of resistance to carbapenems. For this purpose, the presence of OprD protein in the cell wall was detected by Western blot and -lactamase activity by spectrophotometric assay and isoelectric focusing. OprD expression was not detectable in the imipenem-resistant (MIC16 g/ml) strains. It was decreased in half the strains for which MICs of imipenem were 2 to 8 g/ml and was close to a normal level in the most susceptible strains (MIC 1 g/ml), thus demonstrating a direct correlation between the level of susceptibility to imipenem and the level of OprD expression. No imipenemase activity was detected in imipenem-resistant strains. Synergy between imipenem or meropenem and BRL42715 was observed for all of the strains, demonstrating the role of cephalosporinase in carbapenem resistance. Within each pattern of susceptibility, the mean MICs of -lactam agents other than carbapenems were similar, whether the strains were susceptible or resistant to imipenem. Conversely, the mean MICs of imipenem or meropenem for either the imipenem-resistant or the imipenem-susceptible strains were similar, regardless of the susceptibility of these strains to the other -lactam agents. Thus, when several mechanisms of resistance to -lactam agents are present in the same strain ofPseudomonas aeruginosa, there is no additive effect between these mechanisms.  相似文献   

13.
Summary The purpose of the experiments reported below was to examine the response in sporulation medium of the three diploid cell types MAT MAT, MAT MAT (asporogenic diploids) and MAT MAT (sporogenic diploid) to erythromycin, a specific inhibitor of mitochondrial protein synthesis (MPS) in vegetative cultures, and cycloheximide, a specific inhibitor of cytosol protein synthesis (CPS) in vegetative cultures. When MAT MAT diploids are transferred to sporulation medium a significant fraction of total protein synthesis (CPS + MPS) becomes sensitive to erythromycin in contrast to the behavior of MATa MATa and MAT MAT diploids in which the resistance of CPS to erythromycin is maintained. The decompartmentalization of erythromycin sensitivity is thus cell type specific. Erythromycin stimulates total RNA synthesis of MAT MAT cells in sporulation medium but not of MAT MAT and MAT MAT cells. Cycloheximide inhibits protein synthesis and stimulates RNA synthesis in all three diploid cell types. An erythromycin resistant mutant, shown to be due to a mutation of the mitochondrial genome, exhibited only partial resistance of CPS to erythromycin in sporulation medium in the background of the MAT MAT mating type genotype. Total RNA synthesis in this mutant was not stimulated. The results reported indicate that mitochondrial functions during sporulation are not restricted to those involving respiratory metabolism.  相似文献   

14.
Summary A small population of T cells does not express the conventional T cell receptor characterized by the and polypeptide chains (TCR) but instead, two polypeptides termed and (TCR). This alternative receptor is able to recognize antigen. It appears early in T cell ontogeny, but its role in the thymus prior to the availability of TCR remains unclear. In selected sites such as skin or gut TCR predominates in mice which might suggest a role of T cells in the first line of defense against infection, T cells secrete lymphokines and display cytotoxic activity. However, their activation requirements may differ from what is known for T cells since MHC-nonrestricted and also CD4 and CD8 negative T cells have been described. Preferential activation by mycobacterial antigens possibly indicates a special repertoire of the T cells. In various diseases slightly increased numbers of T cells were found, but these preliminary studies have not yet provided evidence for a major pathogenetic role of T cells.List of abbreviations C constant region (immunoglobulin or TCR gene segment) - CD4 cluster of differentiation 4 (mainly on helper cells) - CD8 cluster of differentiation 8 (mainly on cytotoxic cells) - D diversity region (immunoglobulin or TCR gene segment) - DNA desoxyribonucleic acid - IL2 interleukin 2 - J joining region (immunoglobulin or TCR gene segment) - kD kiloDalton - MHC major histocompatibility complex - NK natural killer (cells) - RA rheumatoid arthritis - TCR T cell receptor - V variable region (immunoglobulin or TCR gene segment)  相似文献   

15.
The contribution of induction and stable derepression of chromosomal class I -lactamases to -lactam antibiotic resistance was studied in clinical isolates ofPseudomonas aeruginosa collected from patients treated with -lactam antibiotics. Multiple isolates from the same patient were characterized by O-serotyping as a primary screen, combined with pyocin typing. Sonicated extracts of cells were assayed for chromosomal and plasmid-mediated -lactamases by isoelectric focusing and cloxacillin inhibition studies. The specific -lactamase activity, basal and induced, with cefoxitin was determined to differentiate strains with inducible or derepressed production of the enzyme. Beta-lactamase induction was performed in each strain against the -lactam agents used in the therapy of each patient. The observations showed that induction against older penicillins such as penicillin, amoxicillin, and amoxicillin/clavulanate resulted in a moderate to strong increase in -lactamase activity, whereas the results obtained with first-generation cephalosporins varied with the -lactam agent tested. Third-generation cephalosporins were weak inducers of -lactamases, and their use as therapy preceded the appearance of strains that produce chromosomal group I -lactamases constitutively. These strains showed a remarkable reduction in sensitivity to ureidopenicillins, carboxipenicillins, third-generation cephalosporins, and monobactams, but not to carbapenems.  相似文献   

16.
    
We examined the effects of transforming growth factor-1 (TGF1) and a neutralizing monoclonal antibody on two phases of early chick embryo development: gastrulation and chondrogenesis. We carried out experiments in vivo and in vitro on mesoderm cells from the gastrulating embryo at day 1, and on sclerotome cells from day 3 embryos, having previously shown that this factor is present among these cells at these stages of development. Addition of the antibody to cultures of these cells produced a dose-dependent decrease in cell outgrowth and spreading and concomitantly reduced fibronectin deposition. In vivo studies of the effects of TGF1 on mesoderm during gastrulation were carried out by grafting beads carrying this agent into gastrulating embryos. We used beads of ion-exchange resin as well as hydrolysed polyacrylamide, and found that the grafts produced an accumulation of mesoderm cells around the implant and, at later stages, the formation of enlarged somites. There was no effect on embryonic axis formation. Studies of bromodeoxyuridine (BrdU) incorporation indicated that the mesoderm accumulation was due, at least in part, to an increase in cell proliferation. However, examination of the effect of TGF1 on BrdU incorporation by mesoderm during gastrulation and sclerotome cells in vitro indicated in inhibition of cell proliferation, an inconsistency explained in terms of the variation between the in vivo and in vitro conditions. We conclude that TGF1 is both appropriately located, and is able, to influence cell proliferation among the mesodermal cell populations during early development, and that this effect contributes to the overall control of mesodermal morphogenesis. Chondrogenesis was studied in vitro using micromass cocultures of sclerotome cells with notochordon a permeable substratum. Under these conditions, the addition of TGF1 caused an increase in the deposition of Alcian blue-stainable material, indicating a stimulation of chondrogenesis. We suggest that this result, coupled with the previous demonstration that TGF1 is present among the sclerotome cells in the embryo at this time, supports the contention that this factor exerts a regulatory effect on sclerotome cell differentiation.  相似文献   

17.
Summary The mengovirus-induced 250 S RNA polymerase structure was separated from the bulk of the soluble protein and membrane particulates by two cycles of sucrose gradient centrifugation. After labeling cells 2–5 hours after infection the major polypeptides detected were capsid polypeptides and and polypeptides F and G. Intermediate amounts of capsid precursor s and capsid polypeptide were also present. Small amounts of capsid precursors A, B, and D1 and stable polypeptide E were also detected. About 18–20 per cent of the labeled protein associated with the 250 S polymerase structure was present in mengovirus particles which cosediment with the polymerase preparation. After removal of these virus particles by CsCl gradient centrifugation the RNA-associated proteins recovered in the CsCl gradient pellet contained polypeptides , , and , capsid precursors A and B and the stable polypeptides E, F, and G. The capsid polypeptide is sharply reduced in amount and the reduction can be accounted for the by percent of mengovirus contaminating the polymerase structure. This polypeptide composition resembles the composition of poliovirus procapsid polypeptides in that it contains precursor capsid polypeptides and a low amount of capsid polypeptides .This work was initially presented at the 1973 FASEB Meeting in Atlantic City, New Jersey, and taken, in part, from the doctoral dissertation of W. T.Loesch, Jr.  相似文献   

18.
To determine the relative presence of TCR+ and TCR+ T cells in synovial tissue from patients with various types of inflammatory synovitis and in tissues from patients with a number of chronic T cell-mediated conditions, we stained frozen tissue sections with monoclonal antibodies in indirect immunofluorescence assays. In tissues obtained from patients with chronic T cell-mediated granulomatous conditions (Wegener's granulomatosis, lymphomatoid granulomatosis, granuloma annulare, Langerhan's cells granulomatosis, pigmented villonodular synovitis, Takayasu's arteritis, and talc granulomatosis), the T cells present were predominantly TCR+, without an increased presence of TCR+ cells. In contrast, 6 of 14 (43%) synovia from patients with rheumatoid arthritis (RA) showed increased TCR+ T cells (3–10 cells/hpf). The RA synovia with increased TCR+ cells present had an increased tissue inflammation score compared to RA synovia with few TCR+ cells [18.6±5.8 versus 11.6±4.2 (mean±SE),P<0.05]. In contrast, synovia from patients with osteoarthritis, systemic lupus erythematosus, and trauma did not show an increased presence of TCR+ T cells. Thus, in cellular inflammatory infiltrates the presence of increased TCR cells is not a component of noninfectious granulomatous inflammation but is found in approximately 40% of RA synovia with high levels of inflammation.  相似文献   

19.
Apart from cellular immunity and immunopathology, various cytokines have been implicated in malaria-associated immunosuppression. In this study, serum levels of transforming growth factor- (TGF-) were determined with an enzyme-linked immunosorbent assay in 37 patients with acutePlasmodium falciparum malaria prior to, during, and after therapy and in 17 healthy controls in Bangkok, Thailand. Patients were treated with artesunate and mefloquine. TGF- serum levels were found decreased prior to treatment (14±11 pg/ml versus 63±15 pg/ml in healthy controls;P<0.05). The serum concentrations of TGF- increased after initiation of treatment and were within normal range on day 21. Serum levels of both tumor necrosis factor-ga (TNF-) and soluble TNF-receptor 55 kDa were inversely correlated to serum levels of TGF- (r= –0.667 andr=}-0.592, n=37; respectively,P < 0.05 for both). No correlation between parasitemia and serum levels of TGF- could be found. The results are compatible with a decreased production and release, an enhanced clearance or utilization, or tissue accumulation of TGF- in acuteP. falciparum malaria.  相似文献   

20.
The Ca2+ channel subunits 1C-a and 1C-b were stably expressed in Chinese hamster ovary (CHO) and human embryonic kidney (HEK) 293 cells. The peak Ba2+ current (I Ba) of these cells was not affected significantly by internal dialysis with 0.1 mM cAMP-dependent protein kinase inhibitor peptide (mPKI), 25 M cAMP-dependent protein kinase catalytic subunit (PKA), or a combination of 25 M PKA and 1 M okadaic acid. The activity of the 1C-b channel subunit expressed stably in HEK 293 cells was depressed by 1 M H 89 and was not increased by superfusion with 5 M forskolin plus 20 M isobutylmethylxanthine (IBMX). The 1C-a·2·2/ complex was transiently expressed in HEK 293 cells; it was inhibited by internal dialysis of the cells with 1 M H 89, but was not affected by internal dialysis with mPKI, PKA or microcystin. Internal dialysis of cells expressing the 1C-a·2·2/ channel with 10 M PKA did not induce facilitation after a 150-ms prepulse to +50 mV. The Ca2+ current (I Ca) of cardiac myocytes increased threefold during internal dialysis with 5 M PKA or 25 M microcystin and during external superfusion with 0.1 M isoproterenol or 5 M forskolin plus 50 M IBMX. These results indicate that the L-type Ca2+ channel expressed is not modulated by cAMP-dependent phosphorylation to the same extent as in native cardiac myocytes.  相似文献   

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