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PubMed2006

Decreased expression of the adhesion molecule desmoglein-2 is associated with diffuse-type gastric carcinoma.

Desmoglein-2 (Dsg2) is one of the components of the cell-cell adherence junction. We previously reported that loss of heterozygosity at chromosome 18q12, on which the Dsg2 gene exists, is frequently found in diffuse-type gastric cancers. This study investigated the relationship between Dsg2 expression and diffuse-type gastric cancers. A total of 112 primary tumours resected from patients with gastric cancer were stained with a monoclonal antibody against Dsg2 and examined for correlations between the expression of Dsg2 and various clinicopathological factors, including loss of heterozygosity on chromosome 18q and prognosis. Dsg2 is immunolocalised at cell-cell boundaries in normal gastric mucosa. Loss of Dsg2 expression was observed in 33 of 112 gastric tumours. There was a statistically significant correlation between a decrease in Dsg2 staining and loss of tumour differentiation (P < 0.001), tumour macroscopic feature (P < 0.001) and peritoneal dissemination (P = 0.023), and Dsg2-negative staining was correlated significantly with loss of heterozygosity on chromosome 18q12 (P = 0.001). The prognosis of patients with Dsg2-negative tumours was significantly worse than that of those with Dsg2-positive tumours (log rank, P < 0.01), while multivariate analysis revealed that Dsg2 was not an independent prognostic factor. These findings suggest that decreased expression of Dsg2 is associated with diffuse-type gastric cancers and poor prognosis in gastric carcinoma.

Cadherins↗
PubMed2002

Utility of immunohistochemical detection of prostate-specific Ets for the diagnosis of benign and malignant prostatic epithelial lesions.

BACKGROUND: Human prostate-specific Ets (hPSE) belongs to the Ets family. It regulates the proliferation, differentiation, and development of prostate epithelial cells. A recent study showed that hPSE can be detected in normal glands but not in cell lines established from prostate cancer (PCA), suggesting a translational disorder of hPSE from mRNA to protein in PCA. Immunohistochemical detection of hPSE could therefore be another method of differential diagnosis of PCA from other proliferative conditions in the prostate. METHODS: An immunohistochemical detection of hPSE was carried out on the whole mounted prostatectomy specimen obtained from 19 cases with PCA. RESULTS: Basal and secretory luminar cells showed a diffuse cytoplasmic staining for hPSE in normal glands, hyperplastic glands, and prostate intraepithelial neoplasia lesions. Whereas approximately 30% of PCA lesions showed a negative staining for hPSE, the positive rate for hPSE between PCA and benign glands or prostate intraepithelial neoplasia (PIN), was statistically significant (P < 0.05). Staining intensities in normal glands, hyperplastic glands, and PIN lesions were similar, but generally stronger than those in PCA lesions. CONCLUSIONS: Negative immunoreactivity for hPSE strongly suggests malignancy in the prostate glands. Decreased immunoreactivities of glands for hPSE could suggest PCA.

Aged↗
PubMed1978

Isolation of lipopolysaccharides and the effect of polymyxin B on the outer membrane of Corynebacterium autotrophicum.

Lipopolysaccharides (LPS) from Corynebacterium autotrophicum were isolated and analyzed. Autotrophically grown cells contained 2--5 mg of partly purified LPS per g dry weight of lyophilized cells. Serological cross reaction with Lipid A antigen of Salmonella minnesota confirmed the presence of LPS in C. autotrophicum. Electron microscopy of negatively stained Polymyxin B-treated cells showed formation of blebs on the Outer Membrane indicating an interaction of Polymyxin B specifically with LPS. Up to now, no Gram-positive organisms are known which contain any LPS. Thus, C. autotrophicum, though giving opposite results when the Gram-staining reaction was applied by several authors, has to be classified into the group of Gram-negative bacteria.

Cell Wall↗
PubMed1997

Immunohistochemical localization of estrogen receptor in the normal canine female genital tract.

The distribution of estrogen receptor (ER) in the ovaries and uterus was studied throughout the estrous cycle in the bitch. The stage in the estrous cycle of 25 dogs was assessed by gross and histologic appearance of the uterus and ovaries and blood steroid hormone values. Demonstration of ER was performed by an indirect immunohistochemical technique with monoclonal antibodies. ER was found as a red nuclear staining in the surface, crypt, and glandular epithelium; in endometrial stroma cells; and in smooth muscle cells of the tunica muscularis of the uterus. Total scores of ER-positive cells varied during the estrous cycle, with the highest scores in the early proliferative stage and the lowest scores in the early secretory stage of the estrous cycle. These results are in concordance with the observations in other animals and the human uterus. In the canine ovaries, positive staining for ER was present in surface epithelium and subsurface epithelial ingrowths, which is in contrast with negative staining of human ovaries. This study confirms the earlier hypothesis that the epithelial ingrowths in canine ovaries may be responsive to blood steroid hormones.

Animals↗
PubMed2001

Correlation between c-erbB-4 receptor expression and response to gemcitabine-cisplatin chemotherapy in non-small-cell lung cancer.

BACKGROUND: While the overexpression of c-erbB gene family in several malignancies is associated with poorer prognosis, the association between the expression of the cellular markers and the response to chemotherapy is not yet clear. In this study we investigated the expression of c-erbB-4 receptor in NSCLC and correlated it with the response to gemcitabine-cisplatin combination chemotherapy. PATIENTS AND METHODS: Forty-three NSCLC patients with histologically or cytologically proven disease were treated with gemcitabine-cisplatin combination chemotherapy. Immunohistochemical stains for c-erbB-4 receptor were performed in 20 cases on paraffin sections using the avidin-biotin-peroxidase method. RESULTS: Two patients achieved complete response (5%), and 16 achieved partial response (37%) yielding an overall objective response rate of 42%. Minimal response was observed in seven patients (16%) and disease stabilization in 7%. Immunohistochemical stain was positive for the presence of c-erbB-4 receptor in 25% of patients, and negative in 75%. No response was documented in c-erbB-4 positive patients (0 of 5) while an objective response (complete, partial or minimal) was seen in 11 of 15 (73%) c-erbB-4 negative patients. Negative stain for c-erbB-4 significantly favored response to gemcitabine-cisplatin combination (P < 0.01). CONCLUSION: C-erbB-4 expression status showed no correlation with survival and cannot be accepted at this time as a guiding factor for therapeutic management. These interesting results deserve further evaluation in a large-scale prospective trial before treatment recommendations on the basis of c-erbB-4 presence can be finally made.

Adult↗
PubMed1988

Distinction between two molecular species of type V collagen from human post-burn granulation tissues.

Human type V collagen was purified from post-burn granulation tissues, and was demonstrated to exist in two different molecular assemblies consisting of [alpha 1(V)]2 alpha 2(V) and alpha 1(V)alpha 2(V)alpha 3(V) heterotrimers which are designated as type V(112) and V(123) collagens, respectively, in this paper. The two molecular species were separated by salt fractionation at neutral pH under non-denaturing conditions. When crude type V collagen was dialyzed against phosphate-buffered saline at 4 degrees C, mainly collagen V(112) precipitated, leaving collagen V(123) in the solution. Type V(112) collagen, but not type V(123), precipitated at 0.15 M NaCl in 50 mM Tris-HCl buffer (pH 7.5), whereas the type V(123) molecule precipitated at 4.5 M NaCl in the same buffer. When the crude type V collagen was electrophoresed under non-denaturing conditions, two bands were observed; and it was confirmed that the fast-migrating band was composed of [alpha 1(V)]2 alpha 2(V) and the slow-migrating band was alpha 1(V)alpha 2(V)alpha 3(V). Both alpha 1 and alpha 2 chains of V(112) showed biochemical properties that were very similar, if not identical, to those of the corresponding alpha chains of V(123) judging from amino acid compositions, peptide mapping patterns obtained following treatment with cyanogen bromide and lysyl endopeptidase, and periodic acid Schiff and concanavalin A stainings. Alpha 3 chain, in contrast, was distinct from both alpha 1 and alpha 2 chains. The amino acid composition and peptide maps of alpha 3 chain were similar to some extent, but not identical, to those of the alpha 1 chain. The intensity of carbohydrate stainings of the alpha 3 chain was clearly different from that of the alpha 1 chain. The negatively stained segment-long-spacing crystallites of the two molecular species exhibited an identical banding pattern. The crystallite derived from collagen V(112) was usually in a dimeric form exhibiting the C-C terminal junction, but that of collagen V(123) was mostly in a monomeric form. Differences between the two molecular species is ascribed to the presence of the alpha 3 chain in collagen V(123).

Amino Acids↗
PubMed2002

Superficial acral fibromyxoma: report of two cases.

Superficial acral fibromyxoma (SAFM) is a rare soft tissue tumor that has recently been delineated as a separate entity. We report 2 cases of SAFM and discuss its pathological features and differential diagnosis. Both patients had lesions on the toe. In 1 patient, the tumor was found after nail extraction, which had been performed for the treatment of onychomycosis, whereas in the other patient the tumor itself was the reason for seeking dermatological assistance. Biopsies from both cases demonstrated similar features. There was a moderately circumscribed, non-encapsulated tumor extending through the whole dermis. The neoplasm was composed of spindle and stellate cells with slight nuclear atypia arranged in a loose storiform, partly fascicular growth pattern. In 1 case, strands of cells with rather wavy nuclei were seen at the periphery of the tumor. Mitotic figures were scarce. The neoplastic cells were embedded in a myxoid stroma with increased numbers of small blood vessels and scattered mast cells. Immunohistochemically, the tumor cells showed weak focal positivity for CD34 and stained negatively for S-100 protein and alpha-smooth muscle actin. In 1 case epithelial membrane antigen (EMA) was negative, whereas in the second case focal expression of EMA by neoplastic cells was seen. Alcian blue staining revealed abundant mucinous material within the stroma. In conclusion, SAFM represents a distinct entity in the spectrum of cutaneous myxoid tumors. The differential diagnosis of SAFM includes various myxoid neoplasms and tumors with a predilection for distal parts of the extremities.

Aged↗
PubMed1992

Binding and growth-stimulation of cervical cancer cell lines by prolactin.

Two cervical cancer cell lines CC7-T and Si-Ha were employed to observe the relationship between cervical cancer and prolactin. By immunocytochemical and indirect immunofluorescent assays using two prolactin monoclonal antibodies PRL-149 and PRL-151, both cell lines with added prolactin (10 ng/mL) were noted to be positive for PRL-151, but negative for PRL-149. The control cell lines from ovarian cancer and the myeloma lines were both stained negative. By using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, it was noted that CC7-T and Si-Ha grew better in the presence of various added concentrations of prolactin, ranging from 0.1 to 1,000 ng/mL, suggesting that prolactin may enhance the growth of cervical cancer. The degree of stimulation appears to depend on cell differentiation. However, prolactin levels in the cultured supernatant were undetectable by the enzyme immunoassay (EIA) method. We postulate that prolactin can bind and stimulate the growth of some cervical cancer cell lines, probably through the prolactin receptor rather than by autocrine regulation.

Animals↗
PubMed1977

Demonstration of an avian adenovirus as the causative agent of marble spleen disease.

A purification procedure, using chloroform or fluorocarbon extraction and centrifugation on a cushion of cesium chloride (CsCL), was designed to isolate the causative virus of marble spleen disease. Virus was purified, inoculated into turkeys, and subsequently reisolated by purification from the spleen of inoculated turkeys, thus fulfilling Koch's postulates. Splenic antigen was detected by the agar gel precipitin test, and viral inclusions with viral particles were observed by light and electron microscopy. Results of further studies indicated splenic lymphoreticulum cell hyperplasia was a sensitive indicator of marble spleen disease virus (MSDV) infection. Direct fluorescent antibody staining revealed nuclear fluorescence in virus-infected splenic cells from turkeys inoculated with purified MSDV. With negative stain electron microscopy, MSDV was observed to be 90 nm across with an icosahedral capsid composed of 252 capsomeres. This morphologic feature was consistent with that of an avian adenovirus. Serologic evidence for classification of MSDV as an adenovirus was the cross reaction of MSDV antigen with antiserum to turkey adenovirus serotypes TA-1 and TA-2 in the agar gel precipitin test.

Adenoviridae↗
PubMed1980

Immunoelectronmicroscopical investigations on isolated collagen fibrils.

Isolated collagen fibrils treated with type-specific antibodies can be stained using a peroxidase-antibody complex. The staining pattern of the fibrils with this peroxidase-antibody complex is demonstrated and compared with the normal negative staining pattern of the fibrils. The possible binding sites of the anticollagen antibodies on the fibrils is also discussed.

Animals↗
PubMed1991

Increased vasopressin immunoreactivity in the rat brain after a postmortem interval of 6 hours.

Enhanced immunocytochemical staining of vasopressin-containing neurons was observed after incubation of rat brain slices in Ringer medium for 6 h at room temperature, as compared to brain tissue fixed immediately after death. Hypothalamic vasopressin neurons in the supraoptic nucleus, the paraventricular nucleus and the suprachiasmatic nucleus stained more intensely after a postmortem interval of 6 h. Extrahypothalamic vasopressin neurons (VP) in the bed nucleus of the stria terminalis, the medial amygdala and the locus coeruleus proved to be stained as well. Extrahypothalamic VP neurons in the locus coeruleus could, until now, only be visualized after in vivo pretreatment with colchicine. In addition, staining was observed at two new sites, the dorsal raphe nucleus and the lateral septum. Staining of VP was corroborated by application of different antibodies directed against the intact vasopressin molecule as well as by antibodies directed against the other parts of the vasopressin precursor molecule, i.e. neurophysin and glycopeptide. The specificity of the VP-staining was validated by using pre-immune serum and using Brattleboro rat brain tissue, resulting in a negative staining in both cases. Furthermore, homogenated punches of the suprachiasmatic nucleus were submitted to iso-electric focussing on polyacrylamide gel, followed by press blotting and subsequent immunocytochemical staining for vasopressin. Iso-electric foccussing enabled us to characterize and quantify peptides in the suprachiasmatic nucleus. The vasopressin content increased 6 h postmortem, while c-terminal glycopeptide and neurophysin levels remained stable. Similar results were observed in the suprachiasmatic nucleus from decapitated rats whose brains were left intact in the skull for 6 h at room temperature.

Animals↗
PubMed2005

SNARE proteins and caveolin-1 in stallion spermatozoa: possible implications for fertility.

Proteins implicated in the "SNARE hypothesis" for membrane fusion have been characterized in the acrosome of several mammalian species, and a functional role for these proteins during the acrosome reaction has been proposed. We have investigated the presence of SNAREs in equine sperm, using semen samples obtained from stallions with varying fertility. Immunocytochemical analysis revealed that members of different SNARE families can be detected on the acrosome of equine sperm, notably in the acrosomal cap and equatorial segment. These proteins include the t-SNARE syntaxin, the v-SNARE synaptobrevin/VAMP, the calcium sensor synaptotagmin, and the ATPase NSF. Also present is caveolin-1, a component of lipid rafts. Stallions with fertility problems presented the worst quality of sperm and acrosomal membrane, and had less sperm cells stained positively for SNAREs and caveolin-1, than sperm from fertile donors (p < 0.001). Ubiquitin surface staining was also performed and it seemed to inversely correlate with stallion fertility, supporting data obtained with the negative staining technique. A male-related problem was confirmed when mares that had failed to impregnate with samples from an infertile stallion were successfully inseminated with sperm from a fertile donor. Furthermore NSF, synaptotagmin and caveolin-1 staining seemed to be useful in predicting stallion fertility, i.e. significantly more sperm cells stained positively for these proteins in samples from fertile males. Although these results need to be expanded on a larger scale, they suggest that acrosomal and surface staining of equine sperm with novel probes may constitute useful tools in predicting stallion fertility.

Acrosome↗
PubMed1994

Overexpression of p53 protein in adenocarcinoma of the pancreas.

Mutations in the p53 tumor suppressor gene are frequently identified in human neoplasms. These mutations may be associated with stabilization and, therefore, with overexpression of the p53 protein product as determined by immunohistochemical staining. Using a new antigen retrieval method and a polyclonal antibody to p53 (CM-1), the authors examined 48 formalin-fixed paraffin-embedded adenocarcinomas of the pancreas for overexpression of the p53 gene product. These 48 carcinomas were obtained from a series of patients with well-documented clinical histories and extensive follow-up. The carcinomas had been analyzed previously for K-ras gene mutations, tumor ploidy, and tumor proliferating index. Specific diffuse nuclear staining for the p53 protein was identified in 19 of the 48 (40%) infiltrating carcinomas examined. Focal or negative staining was seen in the remaining 29 cases (60%). In addition, 17 of the neoplasms contained synchronous in situ carcinomas; two (12%) of these displayed diffuse nuclear staining for the p53 protein. Overexpression of p53 was associated with aneuploidy (P = .05), which had been a poor prognosticator in this series of adenocarcinomas of the pancreas. Although overexpression of p53 appeared to be associated with poor prognosis (hazard ratio, 1.8; P = .07), this was not statistically significant. Overexpression of p53 was not significantly associated with K-ras oncogene mutations or tumor proliferating index. The authors conclude that overexpression of the p53 protein occurs frequently in invasive adenocarcinomas of the pancreas and in some in situ carcinomas, as well.

Adenocarcinoma↗
PubMed1985

Immunohistochemistry as an aid in the diagnosis of Hirschsprung's disease.

The interpretation of rectal suction mucosal biopsies taken for the purpose of ruling out Hirschsprung's disease (HD) can be especially difficult in neonatal patients because of ganglion cell (GC) immaturity. Acetylcholinesterase histochemistry on frozen sections can be helpful but requires experience and may be complicated by excessive mucosal hemorrhage. The authors retrospectively have studied 27 patients, including 11 patients with HD, on whom conventionally fixed and embedded tissue was available, using an immunoperoxidase system directed against neuron-specific enolase (NSE) and S100 protein. NSE immunostaining produced intense staining of GC perikarya, greatly facilitating recognition of small immature forms. S100 immunostaining also highlighted GC as prominent negative stained cells surrounded by the positivity of Schwann cells. Both stains were helpful in demonstrating the overall pattern of microinnervation and its relationship to possible GC. The authors conclude that NSE and S100 immunostaining may facilitate interpretation of rectal mucosal biopsies when Hirschsprung's disease is being considered as a possibility.

Acetylcholinesterase↗
PubMed1988

Effect of trypsinization on the immunostaining of formalin-fixed, paraffin-embedded tissues.

We have investigated the action of trypsin treatment on formalin-fixed, paraffin-embedded tissue sections prior to immunostaining with a variety of commercially available poly- and monoclonal antibodies commonly used in surgical pathology. Although enzymatic predigestion often markedly reduced the background and enhanced the immunoreaction for certain antibodies, false negative staining or no enhancement of the staining was observed with other antibodies. We conclude that the indiscriminate practice of trypsinization in immunohistochemical procedures could be a significant cause of false negative results and of discrepancies between laboratories. Therefore, each laboratory must develop its own quality control program for variables such as enzymatic predigestion.

Antigen-Antibody Reactions↗
PubMed1985

Electron microscopic studies of lipopolysaccharides from phase I and phase II Coxiella burnetii.

Lipopolysaccharides from phase I (LPSI) Coxiella burnetii Ohio and Nine Mile strains and from phase II (LPSII) Nine Mile stain were negatively and positively and examined with the electron microscope. The ultrastructure of LPSI and LPSII positively stained with uranyl formate or uranyl acetate was ribbon-like. When negatively stained with uranyl acetate, LPSI was ribbon-like but LPSII exhibited hexagonal lattice structures. However, LPSII stained negatively with sodium phosphotungstate and ammonium molybdate exhibited hexagonal lattice ultrastructures which were not identical to those observed when negatively stained with uranyl acetate. The hexagonal lattice structures formed in vitro were due to the interactions of LPSII and the staining reagents rather than to protein-LPS interactions. The differences in the ultrastructures of LPSI and LPSII are undoubtedly based on variations in their chemical composition.

Coxiella↗
PubMed2006

Two sporadic cases of adult-onset progressive mucinous histiocytosis.

Progressive mucinous histiocytosis is a rare, benign, non-Langerhans' cell histiocytosis limited to the skin. Ten cases--all women--in four families and one sporadic case have been described in the literature. The disorder usually begins in childhood and progresses slowly. We report two sporadic cases of adult-onset progressive mucinous histiocytosis in unrelated African-American women, aged 48 and 55 years, respectively, who developed red-brown and flesh-coloured, asymptomatic papules on the face, the arms and the legs without truncal, mucosal or visceral involvement. The lesions showed no spontaneous regression. Both patients lacked associated systemic symptoms, including polyuria, polydipsia or seizures. There was no underlying hyperlipidaemia, paraproteinaemia or lymphoproliferative disease. No family history of similar lesions could be identified. Light microscopy revealed dermal proliferation of spindle-shaped histiocytes with abundant mucin deposition. Electron microscopy demonstrated a high number of myelin figures or zebra bodies in the cytoplasm of histiocytes. On immunohistochemistry, positive staining with macrophage markers--CD68, HAM56 and lysozyme--and factor XIIIa, a transglutaminase present in dermal dendrocytes, and negative staining with Langerhans' cell markers--CD1a and S100--and CD34, a marker present in dermal dendritic cells derived from uncommitted mesenchymal cells, were observed.

Diagnosis, Differential↗
PubMedDate not supplied

Serum level of HER-2/neu in patients with gastric cancer: correlation with HER-2/neu overexpression in gastric carcinoma tissue.

Serum HER-2/neu (c-erbB-2) levels in patients with gastric cancer were evaluated by an enzyme-linked immunosorbent assay and tissue levels of HER-2/neu in the same cohort were determined by immunohistochemistry. Nine (16%) of 57 gastric carcinomas had an overexpression of HER-2/neu detected immunohistochemically. Of these 9 patients, 6 had elevated serum HER-2/neu levels, while 45 of 48 tissue samples with negative staining exhibited normal serum HER-2/neu levels. These results indicated that overall accuracy, positive predictive value, and negative predictive values of their serum measurements were 89, 67 and 94%, respectively. Serum levels of HER-2/neu were correlated with tissue overexpression of HER-2/neu in patients with gastric cancer.

Adenocarcinoma↗