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PubMed1992

Localization of ecto-ATPase in rat kidney and isolated renal cortical membrane vesicles.

Brush-border (BBMV) and basolateral membrane vesicles (BLMV) from rat renal cortex exhibit an ecto-ATPase activity that is distinct from other ATPases. We have examined the cellular and regional distribution of this enzyme in rat kidney using antibodies against rat liver ecto-ATPase. In isolated vesicles, the distribution shown by biochemical assays of ATPase activity was confirmed by immunocytochemistry and Western blotting. Indirect immunofluorescence and immunogold labeling showed that brush borders of the S1 and S3 segments of the proximal tubule (PT) were stained, but the S2 segment was negative. Staining was most intense in the S3 segment. The luminal membrane of the initial part of the thin descending limb of Henle also showed a marked staining. Surprisingly, basolateral plasma membranes of PT had no detectable staining. However, the plasma membrane of endothelial cells was heavily stained, both in larger vessels and in peritubular capillaries. Using an antibody against rat thrombomodulin, a marker for endothelial cell plasma membranes, we showed that preparations of BBMV, BLMV, and endocytic vesicles are all contaminated with these membranes. This may explain, at least partially, the biochemically measured ecto-ATPase activity in renal cortical membrane vesicles. Finally, no specific staining in the kidney was found using polyclonal antipeptide antibodies against the "long form" of liver ecto-ATPase, either by immunocytochemistry or by Western blotting. This indicates either that there is no long isoform of the ecto-ATPase in the kidney or that the intracellular domains of the long form are different in the two tissues.

Adenosine Triphosphatases↗
PubMed2003

Modulation of keratin and connexin expression in limbal epithelium expanded on denuded amniotic membrane with and without a 3T3 fibroblast feeder layer.

PURPOSE: Based on the knowledge that limbal epithelial stem cells (SCs) do not express keratin-3 (K3), connexin (Cx)43, and Cx50, a study was conducted to investigate amniotic membrane (AM) culturing conditions that promote limbal SC expansion. METHODS: Human limbal epithelium was expanded on intact and epithelially denuded AM, with or without a 3T3 feeder layer, and subsequently transplanted to nude mice to induce epithelial stratification and differentiation. Immunostaining and Western blot analysis were used to determine protein expression of K3, Cx43, and Cx50. Expression of integrin-alpha3, -beta1, -alpha6, and -beta4 was investigated by immunostaining. RESULTS: Protein levels of K3, Cx43, and Cx50 in limbal epithelium on intact AM was lower than those on denuded AM. Addition of 3T3 to denuded AM increased the level of Cx43 but decreased that of Cx50. After xenotransplantation, the basal layer of the resultant stratified epithelium on intact AM did not express K3, Cx43, and Cx50, whereas that on denuded AM expressed all three markers. The addition of 3T3 resulted in positive staining of Cx43 and K3 but negative staining of Cx50 in the basal epithelium. After stratification, integrin expression was detected at the basal epithelium-amniotic basement membrane interface in all three culture conditions. CONCLUSIONS: Limbal cultures on intact AM retain a limbal epithelial phenotype, whereas those on denuded AM differentiate into a corneal phenotype. The addition of 3T3 slows but does not prevent corneal differentiation on denuded AM. Such a difference may involve integrin-mediated extracellular matrix interactions.

3T3 Cells↗
PubMedDate not supplied

Expression of p53 protein and prognosis in gastric carcinoma.

A study was carried out to assess whether p53 expression is related to tumour type, grade or pathological characteristics, or to prognosis, in gastric cancer. Immunohistochemical studies were performed to detect p53 protein in sections from 55 consecutive gastrectomy or partial gastrectomy specimens. Tumours were classified for T-stage, histopathological grade and pathological characteristics. Immunohistochemical staining detected p53 protein in 11 (19%) of the 55 specimens. There was no statistically significant difference between patients with p53 positively staining tumours and patients with p53 negatively staining tumours with regard to tumour grade, stage or pathological characteristics (lymph-node infiltration, depth of invasion, necrosis, or necrosis of vessels). Survival time was statistically significantly lower in patients with positively staining tumours (mean survival times 12.0 and 23.4 months, respectively). These results suggest that expression of p53 protein is related to poor prognosis in gastric carcinoma.

Adult↗
PubMed1991

[Ultrastructural and immunohistochemical study of experimental atherosclerosis in Japanese quails].

A marked plaque was produced at the tunica intima of the ascending aorta in all of the Japanese quails of 9 weeks old which fed on atherogenic diet containing 2% cholesterol for 8 weeks, while no structural changes of aortic wall were observed in Japanese quails which fed on normal basic food for the same period. The media of aorta in normal quails consist of smooth muscle cells, myofibroblast-like cells (MF) cells), and many successive elastic membranes. At the atherosclerotic lesion, many MF cells migrated from media into intima, and a part of smooth muscle cells were also differentiated to MF cells. Moreover, the most migrating MF cells differentiated to foam cells at the intimal thickness regions, and a few other MF cells also differentiated into endothelial cells of newly forming capillaries. By the immunohistochemical stainings, medial smooth muscle cells were negatively stained with anti-vimentin antibody, and the majority of cells in the intima (MF cells, foam cells, and endothelial cells) contained vimentin filaments. These results indicate that MF cells play a very important role in the development of atherosclerosis in Japanese quail. The morphologicals study offers some new insights into the evaluation of Japanese quails as an animal model of atherosclerosis.

Animals↗
PubMedDate not supplied

Prognostic significance of heat shock protein 27 (HSP27) in patients with oral squamous cell carcinoma.

Heat shock proteins (HSPs) have been defined as proteins induced by heat shock and other environmental and pathophysiologic stress. Heat shock protein 27 (HSP27) is one of the small heat shock proteins. HSP27 is implicated in protein-protein interactions such as folding, translocation, and prevention of inappropriate protein aggregation. Many of their functions suggest that they play important roles in cancers. Archival tissues from 40 patients with oral squamous cell carcinoma who received primary surgical resection were examined for HSP27 by immunohistochemistry and correlated with clinical stage, lymph node metastasis, histological grade and survival period. HSP27 expression was positive staining (+) in 20 (50%), weak or negative staining (-) in 20 (50%) of total 40 cases. There was no correlation between HSP27 expression and clinical stage, lymph node metastasis and histological grade. However, when compared with clinicopathological features, the expression of HSP27 correlated inversely with survival period. This study suggests that the expression of HSP27 is frequently promoted in patients with oral squamous cell carcinoma and should be considered an independent prognostic factor of oral squamous cell carcinoma patients.

Aged↗
PubMed2000

[Analysis of the expression of BMP-2,3,4,5 in nerve sheath tumors of maxillofacial region].

OBJECTIVE: The aim of present study is to elucidate the relationship between the members of BMP family and the neoplasms of peripheral nerve. METHODS: Eight cases of schwannoma and three cases of malignant schwannoma were collected and all samples were fixed with 10% neutral formalin and embedded in paraffin wax. Five microns thickness sections were prepared for staining with haematoxylin and eosin for histopathological assessment and processed for in situ hybridization for assessing the mRNA transcriptions of BMP-2,3,4,5. Sections of osteosarcoma that previously demonstrated consistent expression of BMP-2 mRNA were included in each batch of staining to serve as positive control. RESULTS: The results showed that all of the neoplastic lesions of nerve sheath showed a consistent expression of BMP-2,3,4,5. The positive signals of benign lesions were obviously increased in the palisading area or the area of accumulated cells. There was no detectable staining in the matrix of tumour and collagenous fiber. The staining intensity was relatively and slightly weak in cells of Antoni B tissue when compared with Antoni A tissue. Nevertheless, the tumour cells in Antoni B tissue also showed BMP-2,3,4 and 5 positively staining. The fibroblasts of schwannoma were negatively stained. The malignant lesions showed higher expression signals of BMPs than benign lesions. CONCLUSION: The results can be concluded that the selected members of BMPs may be involved in the process of growth and progression of the neoplasms of peripheral nerve.

Adult↗
PubMed1979

A histochemical study of the neuro-muscular spindles in the tongue of some rodents.

An investigation was undertaken to study the Neuro-muscular spindles in the tongue (Rattus rattus rufescens and Suncus murinus) by cholinesterase technique, under maintained pH of 5.2, incubation period 20 h., and temperature 38 degrees C (Rattus) and 39 degrees C (Suncus). Neuro-muscular spindles were observed frequently distributed from anterior to posterior of the tongue and took a little darker stain than the ordinary muscle fibres (negatively stained) while the nerve fibres and ganglia took still darker stain. Nerve fibres (myelinated, non-myelinated and tortuous) were seen penetrating and embracing the muscle spindles and most of them ran parallel to the spindles. Ganglia of various shapes (oval, irregular, elongated and rounded) and sizes (large, Rattus and medium and small, Suncus) were AChE-positive. Ganglia small and medium in size, rounded and elongated in shape were arranged in chain-like fashion on the muscle spindles in Suncus (Fig. 9, 10). The blood vessels (artery, vein, and capillary) were recorded either in close association with the muscle spindles or lying parallel to it. In all cases they were closely related and deeply associate either with the nerve fibres of the plexus of the muscle spindles or with the nerve fibres of the neural network of vessel. Perivascular and perimuscular ganglia with pre- and postganglionic nerve fibres were closely related to each other. Nerve endings, dot-like (Rattus) and bulb-like (Suncus) were occasionally recorded. AChE activity was found randomly in the muscle spindles (Fig. 2, 5.) and in the form of dark brown patches in the ordinary muscle fibres.

Animals↗
PubMed1990

[Large-cell intravascular malignant lymphoma].

Neoplastic angioendotheliosis is a rare, severe, disease characterized by neoplastic proliferation of mononuclear cells within the lumen of small blood vessels. The clinical signs are usually dermatological and neurological. We report the case of a 57 year old woman who died after 20 months of subacute dementia. She had had also transient recurrent episodes of right paresthesiae and paresis. CSF proteins were increased. MRI showed areas of high signal in the white matter. Post-mortem showed widespread ischemic lesions, mainly in the subcortical white matter. Microscopically there was marked proliferation of cells in most CNS blood vessels. Similar cells were present in adrenals, liver, uterus, lungs and kidneys. Immunohistochemical studies showed intensive staining for leukocyte common antigen and negative staining for factor VIII-related antigen, a specific endothelial cell marker.

Brain Neoplasms↗
PubMedDate not supplied

Granular-cell tumor of the breast. A cytologic, immunohistochemical and ultrastructural study of two cases.

Two primary granular-cell tumors of the breast are reported. Cytologically and histologically, these tumors had the classic features of small, eccentrically located nuclei and numerous periodic acid-Schiff-positive cytoplasmic granules. The characteristic cytologic features were best appreciated in touch imprints, not in frozen sections. Immunohistochemically, the tumors demonstrated diffuse cytoplasmic staining for S-100 protein but negative staining for myoglobin. The significance of these immunohistochemical staining characteristics, particularly in evaluating the possible histogenesis of these tumors, is discussed. The ultrastructural features of these two tumors are also presented and compared to findings reported by other investigators.

Adult↗
PubMed1984

Interaction of xenogeneic antiglomerular antibodies with foetal pig tissues.

Rabbit anti-swine-glomerular-immunoglobulin (AG Ig) was administered in utero to 14 pig foetuses 40-103 d post-conception. In nine foetuses AG Ig was injected into the umbilical vein and 60 min later kidneys and other organs were collected. In five others, AG Ig was injected via the intact uterine wall, and the tissues were examined after further 11 or 35 d of uninterrupted pregnancy. No signs of glomerular inflammation were found by light microscopy. In electron microscopy, especially in younger foetuses, focal endothelial defects and subendothelial granular "deposits" were seen in deep glomeruli, but they appeared also in control foetuses of corresponding age. Immunofluorescence microscopy showed a strong diffuse linear positivity of the swine-anti-rabbit-Ig conjugate in the capillary loops of deep juxtamedullary glomeruli irrespective of foetal age and dose of antigen injected. Immature glomeruli and S-bodies yielded a poor to negative staining. Proof of swine Ig was negative in all kidneys as well as the test for rabbit and swine Ig in various other organs. Traces of rabbit Ig were only detected in disseminated platelet aggregates of myocardium in the early post-injection period. Ultrastructural enzyme-antibody assay visualized AG Ig throughout all three layers of glomerular capillary basement membrane, and in the early period signs of transendothelial passage and escape of unbound rabbit Ig molecules were evident. The mesangial matrix, cell membranes, and extraglomerular basement membranes remained all negative. As follows, xenogeneic antiglomerular antibodies specifically react with target structures even at the end of the first third of intrauterine life, afflicted being only the deep mature polyanion-coated glomeruli. The foetal immune system is incapable of an adequate autologous antibody response, and we have failed to find even an early glomerular lesion comparable with the postnatal anti-basement-membrane glomerulonephritis.

Animals↗
PubMed1998

Immunolocalization of protease-activated receptor-2 in skin: receptor activation stimulates interleukin-8 secretion by keratinocytes in vitro.

The protease-activated receptor-2 (PAR-2) is a seven transmembrane domain receptor related to the thrombin receptor, which is activated in vitro by cleavage by trypsin. Affinity-purified rabbit IgG raised against a peptide corresponding to the trypsin cleavage site of PAR-2 was used for an immunohistochemical study of skin. The expression of PAR-2 in epidermis was striking, with keratinocytes showing abundant intercellular and cytoplasmic staining. Basal cells showed the strongest staining intensity and the stratum corneum was negative. Staining with control IgG used at the same concentration was consistently negative. The functional expression of PAR-2 by the simian virus transformed human skin keratinocyte cell line SVK14 was demonstrated by Northern blot analysis, flow cytometric analysis and the measurement of intracellular calcium. Treatment of SVK14 with trypsin or a receptor agonist peptide (SLIGKV-NH2) caused a dose-dependent increase in the secretion of the chemokine interleukin-8 (IL-8) in vitro. The effect of the peptide was specific, since control acetylated peptide was without activity. We conclude that PAR-2 is highly expressed by epidermal keratinocytes and receptor activation in vitro leads to increased IL-8 secretion by keratinocytes. These data raise the possibility that PAR-2 may play a role in epidermal homeostasis and inflammatory conditions.

Blotting, Northern↗
PubMed2002

A predominant IgG4 subclass may be responsible for false-negative direct immunofluorescence in bullous pemphigoid.

BACKGROUND: Bullous pemphigoid (BP) is an immune-mediated blistering disease, usually characterized immunopathologically by the linear deposition of IgG and C3 along the basement membrane zone (BMZ) of skin. However, positive deposition of C3 but negative staining for IgG on direct immunofluorescence (DIF) studies has been noted in some patients. METHODS: Twelve patients known to have BP but with absence of staining for IgG were included in this study. Frozen sections of skin specimens from the 12 patients were subjected to IgG DIF, as well as a sandwich double antibody method of staining for IgG, IgG subclasses, and light chains. Enzyme-linked immunosorbent assay (ELISA) using commercially available human IgG subclasses was used to analyze the subclass restriction of FITC-labeled antihuman IgG conjugates. RESULTS: Of the 12 skin specimens with positive C3 and negative IgG on DIF, nine were positive for IgG with the double antibody sandwich method. In addition, all 12 specimens had positive linear staining for the subclass IgG4 along the BMZ with this method. There was no IgG light chain restriction. Two commercially obtained antihuman IgG conjugates, both commonly used in our laboratory for DIF testing, were analyzed for separate IgG subclass specificity by ELISA. Both conjugates showed high reactivity to IgG1 and IgG3 with less reactivity to IgG2 and IgG4. CONCLUSION: These results suggest that the following factors contribute to false-negative staining for IgG on DIF in some BP patients: (i): subthreshold IgG in skin specimens; (ii) limited reactivity of commercial antihuman IgG conjugates to the IgG4 subclass; and (iii) decreased sensitivity of DIF compared with double antibody methods for the detection of IgG. The use of sandwich double antibody immunofluorescence methods to test for IgG and/or IgG subclasses may be helpful in definitively diagnosing BP in patients with negative IgG and positive C3 staining on DIF.

Autoantibodies↗
PubMed1991

Helicobacter pylori in gastric biopsy specimens. Comparison of culture, modified giemsa stain, and immunohistochemistry. A retrospective study.

Antral biopsy specimens of 302 different endoscopic investigations of 200 patients with non-ulcer dyspepsia were studied for the presence of Helicobacter pylori in order to determine the most sensitive detection method. Part of the biopsy was cultured, and part stained using a modification of the Giemsa stain, and with an immunoperoxidase technique using a polyclonal rabbit anti-H. pylori antiserum. Cross-reactivity of this antiserum with other Campylobacter species was minimal. Material from 244 investigations was studied using all three detection methods. Culture was positive in 44 per cent, Giemsa in 78 per cent, and immunoperoxidase in 89 per cent of these biopsy specimens. Only five positive Giemsa stains with negative immunoperoxidase stain were found, whereas in 32 cases a negative Giemsa stain with a positive immunoperoxidase stain was seen. In the latter cases, the bacterial load was very low. The specimens revealed bacteria only sporadically, always confined to the deep layers of the gastric pits. Culture results correlated significantly with the bacterial load observed in the Giemsa stain. It is concluded that culture of H. pylori is the least sensitive detection method, whereas immunoperoxidase staining is the most sensitive. For daily practice the modified Giemsa stain, however, appears to be sufficient to diagnose the presence of the micro-organism.

Adolescent↗
PubMed1996

A rapid method for the detection of hepatitis C virus RNA by in situ hybridization.

The histologic detection of hepatitis C (Hep C) in paraffin-embedded tissue sections has been problematic. We describe the use of a rapid, i.e., less than 2 hours, in situ hybridization technique to detect Hep C by use of a manual capillary action system (MicroProbe Staining System) and a 24-base synthetic multibiotinylated oligonucleotide antisense probe from the prototype Hep C virus base sequence -16 to -13. This technique is rapid, i.e., it requires a 30-minute hybridization time and easily reproducible, and it uses a nonradioactive detection system, i.e., streptavidin-conjugated horseradish peroxidase. We tested formalin-fixed tissue from explanted human livers and found an overall sensitivity of 69%. Furthermore the technique is highly specific, with negative staining in normal liver tissue from four cases of partial hepatic resection for nontumoric diagnoses and in hepatic tissue obtained from cases of primary biliary cirrhosis, familial amyloidosis, and acute and chronic Budd-Chiari syndrome, for a total of seven confirmed Hep C-negative specimens. Staining with probes for Epstein-Barr virus NotI and EBER sequences was negative in Hep C-positive liver sections from both resected native livers at the time of transplantation and biopsy specimens from post-transplantation patients in whom Hep C has recurred. In those livers staining positively with probe against Hep C, the distribution was both patchy, i.e., staining only fairly well-preserved hepatocytes and not all hepatocytes, and intracytoplasmic, supporting the observations of previously published reports. Finally, the technique was employed on formalin-fixed liver biopsy specimens from four patients with recurrent Hep C; there was repeatedly positive staining in all cases. We think this technique could provide a clinically useful adjunct in the diagnosis of Hep C from formalin-fixed tissue from liver biopsy specimens and that it may be useful in the characterization of the pathophysiologic features of Hep C virus infection.

Base Sequence↗
PubMed1998

Primary mucosal melanomas of the nasal cavity and paranasal sinuses. A clinicopathological analysis of 14 cases.

We present 14 patients with primary sinonasal melanomas (SM) identified from 1984-1997 in our archives (11/14 lateral nose, 1/14 nasal septum, 2/14 paranasal sinuses; 8M/6F, mean age 67.7 years, range 39-88 years). Survival was poor (median 9 months) with death related to extensive local disease and/or widespread hematogenous metastases. The following histological subtypes were identified in descending order: amelanotic small blue cell, pleomorphic, epithelioid, spindle cell and myxoid. High mitotic rate and vascular invasion, absence of tumor-infiltrating lymphocytes and regression were features shared by all SM. Negative staining of B- and T-cell markers, LCA, neuroendocrine markers such as NSE, chromogranin and synaptophysin, and CK-negativity excluded olfactory neuroblastoma, small cell undifferentiated carcinoma, and lymphoma. S-100 protein was expressed in all SM, but demonstrated variable staining intensity with areas of complete negativity. HMB45 was strongly and uniformly (>80%) expressed in all undifferentiated small blue cell SM. The pigmented SM were predominantly HMB45-negative. The strong HMB45 staining in amelanotic small blue cell SM is explained by the reaction of HMB45 antibody with an oncofetal antigen found in immature melanosomes. In these poorly differentiated amelanotic malignant melanomas, antibody to HMB45 proved to be a superb diagnostic marker. We therefore strongly advocate the inclusion of HMB45 antibody in the panel of antibodies for initial work-up of undifferentiated mucosal neoplasms, since a negative S-100 stain in small biopsy material may result in incorrect classification of these neoplasms.

Adult↗
PubMed1988

Small cell carcinoma of the ovary. A report of six cases.

Six cases of small cell carcinoma of the ovary are presented. The tumors occurred in women with an average age of 27.5 years. According to the International Federation of Gynecology and Obstetrics (FIGO), two patients had Stage I, three Stage II, and one Stage III disease. The tumors behaved highly malignantly, as four of the patients died from disseminated disease within 20 months. Three of the tumors were found to be associated with elevated serum calcium levels. By light microscopy three of the tumors were originally misinterpreted: one as an undifferentiated tumor, probably of stromal origin; one as a germ cell tumor, probably endodermal sinus tumor; and the third as a granulosa cell tumor. In four tumors examined by electron microscopy, the epithelial nature was confirmed, and three of them contained neuroendocrine granules. Immunocytochemical examination in five cases revealed positive staining for neuron-specific enolase (NSE) and negative staining for beta 2-microglobulin, whereas one case was negative for NSE and positive for beta 2-microglobulin. A positive immunoreaction for parathyroid hormone was observed in three cases (all NSE positive). In two of these a raised serum calcium level was documented. This finding possibly gives a clue to the hypercalcemia so frequently found in these patients.

Adolescent↗
PubMed1988

Ultrastructural analysis of cytochrome oxidase in chick epiphyseal growth plate cartilage.

Histochemical detection of cytochrome oxidase activity in chicken growth plate revealed both positively and negatively stained mitochondria in chondrocytes of all zones, i.e., proliferative, pre-hypertrophic, hypertrophic, and calcifying zones. The proportion of positive to negative cells was lowest in the proliferative zone. As cytodifferentiation progressed, more positively stained cells were present. In positive cells all mitochondria were usually stained, and in negative cells all mitochondria were unstained. A few cells appeared to be in transition and contained both types of mitochondria. The results indicate that chondrocytes utilizing both aerobic and anaerobic metabolism are present in growth plate cartilage and that oxidative metabolism is favored in the more mature cells. The relationship of oxidative metabolism to calcification is discussed.

Animals↗
PubMed1998

Development of Epstein-Barr virus-associated B cell lymphoma after intensive treatment of patients with angioimmunoblastic lymphadenopathy with dysproteinemia.

Evolution of angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) into aggressive B cell lymphoma is thought to be a rare event and the cause of this transformation has not been fully elucidated. We describe two patients with AILD that progressed to aggressive large-cell lymphoma with a B cell phenotype. At presentation, the lymph nodes of both patients showed the typical features of AILD by hematoxylin-eosin staining. Immunohistochemical staining with monoclonal antibodies revealed positive staining of atypical cells with UCHL-1 and negative staining with L-26. In situ hybridization of EBV RNA showed rare positive cells in one patient and was negative in the other patient. At relapse, both patients showed systemic lymph nodes swelling, which is characteristic of diffuse large immunoblastic lymphoma. Single-cell analysis with monoclonal antibodies and immunohistochemical staining showed the monoclonal proliferation of B cells. Southern blot analysis of the lymph nodes showed a rearrangement in both patients of the Ig heavy chain gene and germ line configuration of the T cell receptor beta chain gene. Southern blot analysis using the EBV terminal repeat region probe detected clonal proliferation of EBV in the lymph nodes of both patients. In situ hybridization studies identified considerable EBV mRNA in both patients. These observations suggest that EBV proliferation plays an important role in the development of B cell lymphoma that arises from AILD. We suggest that infection or reactivation of EBV may occur in some patients with AILD, probably due to their immunodeficient state, and that this infection or reactivation is directly involved in the development of B cell lymphoma.

Herpesviridae Infections↗