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PubMed1982

Negative immunoperoxidase staining for lysozyme in nodular subepidermal fibrosis.

Nodular subepidermal fibrosis (NSF) is a clinical entity, the histogenetic origins of which remain unclear. More than 200 such lesions were examined with light microscopy and subdivided into four types based on their relative degree of cellularity. Five examples of each subtype were stained for lysozyme with the peroxidase-antiperoxidase technique. None of the 20 lesions contained cells with lysozyme. We conclude that the basic cell type in NSF is not lysozyme-containing macrophage; it is a different cell, perhaps one of mesenchymal origin.

Histiocytoma, Benign Fibrous↗
PubMed1996

Electron microscopy--tool to diagnostic pathology.

This review suggests electron microscopy applications, particularly for leucocyte surface antigens, tumors and viruses in relation to diagnostic pathology. It also describes the use of conventional staining method such as negative stain and recently developed immunocytochemistry with colloidal gold labelling significantly improved diagnostic value of electron microscopy. The examples have been chosen to demonstrate quantitative aspects in the early recognition of immunopathological states, morphological aspects in identification of both tumors and viruses, preparative techniques of specimens where the method has been widely used and immunogold labelling, including various colloidal gold systems to map specific ligands.

Animals↗
PubMed1997

Vascular endothelial growth factor (VEGF) expression in prostate cancer and benign prostatic hyperplasia.

PURPOSE: Vascular endothelial growth factor (VEGF) is a potent inducer of endothelial cell growth and is expressed at elevated levels in several tumor types. In this study immunohistochemical localization and distribution of isoforms of VEGF were examined in malignant and non-malignant human prostatic tissues. MATERIALS AND METHODS: Immunohistochemical localization of VEGF was performed on thirty well, moderately and poorly differentiated stage D2 prostate cancer specimens and twenty benign prostatic hyperplasia (BPH) specimens. VEGF mRNA was determined by polymerase chain reaction and VEGF protein isoforms were detected by Western blotting of prostate cancer and BPH specimens. RESULTS: Cytoplasmic immunoreactivity for VEGF was detected in tumor cells and peritumoral stromal cells of prostate cancer specimens and in non-malignant glandular epithelial cells and interglandular stromal cells in BPH specimens. Staining was focal with areas of strongly to weakly stained cells adjacent to negatively staining areas. mRNA's for VEGF121, VEGF165 and VEGF189 were present in all benign and malignant prostate specimens. VEGF protein isoforms of molecular sizes corresponding to VEGF165 and VEGF189 were detected in cytosolic extracts of prostate cancers and BPH specimens by Western blotting. In addition, two novel higher molecular weight immunoreactive bands were detected in the prostate specimens. CONCLUSIONS: Widespread distribution of VEGF in prostate cancers and BPH specimens suggest that the VEGF165, VEGF189 isoforms and novel 90 and 110 kD forms detected may contribute to the establishment or progression of these conditions.

Blotting, Western↗
PubMed1997

Utility of Butvar support film and methylamine tungstate stain in three-dimensional electron microscopy: agreement between stain and frozen-hydrated reconstructions.

A random conical tilt reconstruction of negatively stained Saccharomyces cerevisiae fatty acid synthase was used as a model to compute a three-dimensional reconstruction from untilted stain specimens of the molecules in multiple orientations using a three-dimensional projection alignment method. The resulting structure (24 A resolution) has a more uniform resolution than the initial structure and the handedness revealed in the random conical tilt method is preserved. In a similar approach, this model was used to compute a 21-A-resolution frozen-hydrated structure from untilted specimens of the molecules in multiple orientations. Even though the reconstructions are in close agreement, the stain structure appears to enhance the protein density associated with less robust features. These procedures significantly reduce the time and effort required to obtain a three-dimensional reconstruction from frozen-hydrated data with a resolution that is comparable to the best obtained by more laborious methods. The agreement between the stain and frozen-hydrated reconstructions affords convincing evidence concerning the validity of the structure and the information afforded by the two reconstructions significantly enhances the structural analysis of the molecule.

Coloring Agents↗
PubMed1987

A rapid method for staining proteins in acrylamide gels.

A negative staining procedure for the rapid visualization of proteins in acrylamide gels is described. In the absence of proteins, staining of the gel occurs through the reduction of nitroblue tetrazolium by reduced glutathione. No staining occurs in the presence of proteins. The procedure can be completed in 20 min and is at least as sensitive as Coomassie brilliant blue staining.

Electrophoresis, Polyacrylamide Gel↗
PubMed1995

[Clinical significance of dystrophin positive fibers in Duchenne muscular dystrophy].

Dystrophin is a protein product of the Xp 21 gene which is defective in patients with Duchenne muscular dystrophy (DMD). In immunohistochemical staining of dystrophin, the majority of DMD muscle fibers show negative staining. Nevertheless, biopsy specimens from DMD patients labeled with many different antibodies may show a small number of fibers which are clearly dystrophin positive. This very small percentage of dystrophin-positive fibers (DPF) probably represents somatic reversion, suppression of the DMD gene mutation or alternating splicing of dystrophin mRNA. To determine the significance of isolated DPF in muscle specimens of DMD patients, we examined 30 DMD muscle specimens, aged 4 years to 16 years, by the use of monoclonal antibody against the C-terminal region of dystrophin. Additionally, muscle specimens from 2 normal human controls and 2 mice with X-linked muscular dystrophy were used for positive and negative controls, respectively. Muscle specimens from DMD patients and mdx mice showed almost totally negative dystrophin staining in most of their muscle fibers, but in 20 patients, three was a trace of isolated DPF ranging from 0.06% to 0.77%. DMD patients with no isolated DPF seemed to have higher functional disability. In the whole group of 30 patients, a significant negative correlation was found between the abundance of DPF and clinical functional grading (r = -0.85, p < 0.0001, based on linear regression). It is suggested that even the very low concentrations of dystrophin found in DMD patients may have a favorable functional significance.

Adolescent↗
PubMedDate not supplied

Value of immunoperoxidase staining of thyroglobulin in fine needle aspiration cytology of thyroid diseases.

To elucidate the value of thyroglobulin staining by the immunoperoxidase method in fine needle aspiration cytology of thyroid diseases, it was performed on fine needle aspiration smears of 57 cases of various thyroid diseases. Thirteen of 22 cases (59%) with benign nodular goiter were positive. Eight of 14 cases (57%) with papillary thyroid carcinoma were positive. Among these eight cases with positive staining, seven were at clinical stage II or less. Among the other six cases with negative staining, five cases were in clinical stage III or more. There was a significant relationship between clinical stage and thyroglobulin staining (P < .05). One of 10 cases with thyroid cysts was positive. One of four cases with anaplastic carcinoma was positive. One of two cases with follicular thyroid carcinoma was positive. Two cases of subacute thyroiditis were positive. One case of Hashimoto's thyroiditis was positive. Two cases of metastatic thyroid cancer from the ovary were negative. These results reveal that positive thyroglobulin staining was helpful in defining the source of tissue from the thyroid. However, negative staining could not definitively exclude a thyroid origin. Positive thyroglobulin staining in papillary thyroid carcinoma correlated with less advanced clinical stages.

Biopsy, Needle↗
PubMedDate not supplied

[Effect of the contrast conditions using solutions of phosphotungstic acid on the electron microscopic image of the foot-and-mouth disease virus].

A method of negative staining of foot-and-mouth disease virus preparations permits to obtain separately positive (2% phosphotungstic acid solution, pH 3.0) and negative (2% PTA solution, pH 6.8 +/- 8.0) stainings. When a 3--4% PTA solution, pH 6.8 +/- 8.0 is used, simultaneous positive and negative staining of each virion is possible which characterizes the functional heterogeneity of the virion protein membrane in interaction with PTA anions.

Aphthovirus↗
PubMed2004

Prognostic significance of thyroid transcription factor-1 expression in both early-stage conventional adenocarcinoma and bronchioloalveolar carcinoma of the lung.

Thyroid transcription factor 1 (TTF-1) is a diagnostic immunohistochemical marker for primary pulmonary neoplasms, but its utility as a prognostic marker is not well established. Surgical specimens from 100 cases of pulmonary adenocarcinoma were retrieved from the hospital computer system, including 50 cases of conventional adenocarcinoma (CA) and 50 cases of bronchioloalveolar adenocarcinoma (BAC) (32 nonmucinous type and 18 mucinous type). Representative sections were immunostained for TTF-1. Positive immunohistochemical study was correlated with other prognostic parameters. In the CA group, strong or moderate TTF-1 expression was seen in 30 of 50 (60%) patients and was associated with significantly better survival compared with those patients having weak staining (7 cases; 14%) or negative staining (13 cases; 26%) (P <0.01; log-rank test). Spearman and Pearson's correlation showed no significant correlation between TTF-1 expression and tumor grade, size, recurrence, or vascular invasion; therefore, TTF-1 was considered an independent predictor of survival. In the BAC group, TTF-1 was strongly expressed in 34 of 50 cases (68%) and was negative in 16 of 50 cases (32%), including 14 mucinous BACs. Although TTF-1 immunoreactivity was not statistically associated with good survival in BAC patients, those patients with strong immunohistochemical expression showed a trend toward longer survival. Our results indicate that TTF-1 positivity is an independent predictor of better survival, especially in patients with CA. Mucinous and nonmucinous BACs exhibit disparate staining patterns with TTF-1, with nonmucinous BAC demonstrating greater positivity. Although nonmucinous BAC patients showing strong positive staining had longer survival, the difference was not statistically significant, which is probably related to the overall good survival of patients with early-stage BAC.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1998

Multiple giant angiomyolipomas with a polygonal epithelioid cell component in tuberous sclerosis: an autopsy case report.

A recent case of angiomyolipoma (AML) with a prominent component of polygonal epithelioid cells is described. A 27-year-old Japanese male with tuberous sclerosis presented with massive abdominal tumors increasing progressively in size. The patient died of respiratory disturbance and the autopsy revealed massive tumors in the bilateral kidneys, liver and lymph nodes, subependymal giant cell glioma of the brain and lymphangiomyomatosis of the lungs. The giant tumors were an unusual type of AML with a component of polygonal epithelioid cells, which showed a hepatocellular carcinoma-like pattern in some areas. Smooth muscle components comprising spindle cells, short or plump spindle cells and polygonal epithelioid cells frequently exhibited positive staining for HMB-45 but negative staining for epithelial cell markers. The unusual AML presented in this case was thought to be of low-grade malignancy and slow growing. It has been suggested that angiomyolipomas with diffuse areas of epithelioid cell component are potentially malignant. Immunostainings positive for HMB-45 but negative for epithelial cell markers are considered to be useful in differentiating AML with polygonal epithelioid cell component from other tumors, especially from renal cell carcinoma and hepatocellular carcinoma.

Adult↗
PubMed1998

Comparison of helisal rapid blood test and 14C-urea breath test in determining Helicobacter pylori status and predicting ulcer disease in dyspeptic patients.

OBJECTIVE: Noninvasive tests for Helicobacter pylori are used increasingly. Our aim was to compare the Helisal Rapid Blood (HRB) test and 14C-urea breath test (UBT) for determining H. pylori status and predicting ulcer disease. METHODS: Three hundred fifty-one consecutive patients with dyspepsia (mean age 40 yr; range 16-77 yr) had an HRB test and UBT followed by endoscopy with biopsies of the antrum and body for histology and antral urease slide test (CLO test). Patients were excluded if they had previously confirmed ulcer disease, gastric surgery, or anti-H. pylori therapy or were taking nonsteroidal anti-inflammatory drugs. RESULTS: Sixty-three percent of the patients were "gold standard" H. pylori positive (positive CLO test, positive staining), 34% were gold standard negative (negative CLO test, negative staining), and 3% had conflicting CLO test and histology. The UBT was superior to HRB for determining H. pylori status (sensitivity 98% vs 92%, p = 0.04; specificity 100% vs 69%, p < 0.001). The specificity of the HRB decreased with increasing patient age (74% for age <46 yr; 57% for age > or =46 yr). A negative UBT was superior to a negative HRB test for predicting the absence of ulcer disease (47% vs 36 %; p < 0.01). A positive UBT was similar to a positive HRB in predicting the presence of ulcer disease (92% vs 84%; p = 0.23). CONCLUSIONS: The HRB test is inferior to the UBT for determining H. pylori status. The tests have a similar ability to predict the presence of ulcer disease when positive, but a negative UBT is a better predictor of the absence of ulcer disease.

Adolescent↗
PubMed1985

Light and electron microscopic localization of the N-terminal fragment of human pro-opiomelanocortin in the human pituitary gland and in neoplasms.

Immunohistochemical localization of the N-terminal fragment (1-76) (NTF) of human pro-opiomelanocortin (POMC) was studied in human adult and fetal pituitary glands, as well as in pituitary adenomas associated with Cushing's syndrome and in ectopic ACTH-producing tumors. Comparison of localization between NTF and ACTH was performed using mirror sections. Our results indicated concomitant localization of NTF and ACTH in the same cells, not only in normal adult and fetal pituitaries but also in pituitary adenomas and ectopic ACTH producing tumours. Specificity of the NTF staining was confirmed by immunoabsorption. Negative staining of the bovine pituitary gland indicated the immunohistochemical localization of N-terminal (1-45) of human POMC as there is a known species difference in the sequence 1-45 between human and the bovine N-terminal fragment. Presence of NTF in cisterna of rough endoplasmic reticulum indicates its production by small cell carcinoma. These findings, together with the previous studies, suggest that the complete form of POMC is produced in the tumours as well as in normal pituitaries.

Adenoma↗
PubMed1985

Immunohistochemical study of so-called sclerosing haemangioma of the lung.

To elucidate the histogenesis of sclerosis haemangioma of the lung, we examined 7 cases with the immunoperoxidase method using antibodies against several useful marker antigens; secretory component (SC), cytokeratins, epithelial membrane antigen (EMA) for epithelial cells, factor VIII related antigens (factor VIII) for endothelial cells, vimentin and desmin for mesenchymal cells. The results were compared with those of histologically normal lung tissues. Both the characteristic round cells arranged in sheets, which are present predominantly in the solid area and are reported to be neoplastic, and the flattened cells lining blood lakes show positive staining for EMA only, with negative staining for the other marker antigens. These observations suggest that these cells are derived from epithelium rather than mesothelium or from endothelium, and are analogous to type I pneumocytes. This conclusion is supported by their immunohistochemical characteristics, in comparison with the localization patterns of the marker antigens in normal lung tissues. However, the lining epithelial cells of papillary projections in the papillary area and of ducts in the solid area stained for SC and cytokeratins as well as EMA, and their immunohistochemical characteristics are analogous to those of bronchiolar epithelial cells or type II pneumocytes in normal lung tissues.

Adult↗
PubMed1999

Localization of Estrone Sulfatase in Human Breast Carcinomas.

We generated anti-human E1-STS monoclonal antibodies to localize estrone sulfatase (E1-STS) in human breast carcinomas. In particular, we examined the MCF-7 clone E3, ZR-75-1, MDA-MB 231, and MDA-MB-468 breast cancer cell lines and 25 breast carcinomas by either immunohistochemistry or Western blotting analysis. Simultaneously, we analyzed histological data, estrogen receptor (ER) status, progesterone receptor (PgR) status and epidermal growth factor receptor (EGFR) in breast tissue. All were surgical specimens from female patients. Nine of 25 carcinomas were obtained from premenopausal women, and 16 carcinomas were obtained frompostmenopausal women. All cell lines demonstrated positive staining for E1-STS.Interestingly, fine granulated staining of E1-STS on the cell membrane was observed. In addition, Western blotting analysis detected a 65 kD protein with an E1-STS specific band in all breast cancer cell lines regardless of the presence orabsence of E2. Twenty-two of 25 (88.0%) carcinomas showed positive staining forE1-STS, whereas negative staining was observed in the interstitial tissue surrounding tumors. In the premenopausal patients, 8 of 10 carcinomas (80.0%) showed positive staining for E1-STS, whereas 14 of 15 carcinomas (93.3%) revealed positive staining in the postmenopausal patients. The frequency of E1-STS expression was relatively higher in postmenopausal patients than in premenopausal patients but not statistically significant. The intensity of immunostaining for E1-STS depended upon the size of the tumor (NS). There was no correlation between E1-STS expression and other parameters. This evidence suggests E1-STS expression may beinvolved in the development of breast cancer. Further studies are necessary to clarify the relationship between E1-STS expression and prognostic factors. Immunoreactive E1-STS may be localized in cancer cells but not in surrounding tissuesin breast cancer.

Journal Article↗
PubMed1997

Increased accumulation of acidic fibroblast growth factor in left ventricular myocytes of patients with idiopathic cardiomyopathy.

To clarify the pathophysiologic role of fibroblast growth factors in idiopathic cardiomyopathy, we evaluated endomyocardial biopsy specimens obtained from 24 patients (nine with hypertrophic cardiomyopathy [HCM], 12 with dilated cardiomyopathy [DCM], and three with hypertensive hypertrophy) and six controls. All the specimens were stained for acidic fibroblast growth factor (aFGF) and basic FGF (bFGF) with immunohistochemistry. In situ hybridization was carried out for detection of aFGF mRNA. The average diameter of the myocytes, the percent area of interstitial fibrosis, and capillary vessel density were assessed in each biopsy specimen with morphometric methods. Positive staining of aFGF was observed in the myocytes of the biopsy specimens taken from 15 of 21 (71%) patients with cardiomyopathy (six of nine HCM, nine of 12 DCM) and all hypertensive hypertrophy patients but in none of the controls (p < 0.01). The average diameter of the myocytes was significantly larger in the patients with positive aFGF staining than in those with negative staining (23.1 +/- 1.5 versus 18.3 +/- 1.2 microm, p < 0.05). The percent area of fibrosis and the density of capillaries did not differ between the two groups. Intense expression of aFGF mRNA was observed in the myocytes from the patients with positive aFGF protein. In conclusion, the expression of FGF was significantly increased in myocytes obtained from the left ventricle of patients with cardiomyopathy. Acidic FGF may contribute to the hypertrophy of myocytes as the repair response to myocardial injury in patients with idiopathic cardiomyopathy.

Adult↗
PubMed1981

Corneal elastosis in lattice corneal dystrophy: a clinicopathologic report.

The corneal button of a patient with lattice corneal dystrophy and the clinical features of elastotic degeneration was subjected to histochemical and electron microscopic examination. The elastotic material possesses distinct clinical and histological characteristics, in particular its ability to autofluorescence. This material stained positive with Verhoeff-van Gieson (elastic stain), negative to alizarin red (calcium stain), and was insensitive to elastase digestion. The characteristic electron microscopic picture of elastotic tissue and amyloid was also found. The clinical implications of elastotic degeneration are discussed.

Cornea↗
PubMed1986

Generalized trichoepitheliomas with alopecia and myasthenia gravis: clinicopathologic and immunohistochemical study and comparison with classic and desmoplastic trichoepithelioma.

We report on a patient with a syndrome characterized by smooth facial papules and nodules; alopecia of the eyebrows, eyelashes, and most body hair; mild alopecia of scalp hair; possibly hypohidrosis; and myasthenia gravis. The clinical, histologic, and immunohistochemical findings are compared with classic and desmoplastic trichoepitheliomas. All fourteen biopsy specimens of the patient showed a lacelike network of basaloid cells with follicular differentiation and a prominent stroma with focal alkaline phosphatase activity, as in fourteen comparison specimens of classic trichoepithelioma. Studies with antikeratin antibodies of various specificities also revealed similar patterns. The tumor cells showed a keratin phenotype characteristic of cells of the infrainfundibular outer root sheath, that is, positive staining with basal keratinocyte markers, negative staining with suprabasal keratinocyte markers, and patchy staining with LP2K (against keratin 19). beta 2-Microglobulin expression was partially or totally absent. It is concluded that the lesions in our patient actually are trichoepitheliomas. The condition may represent a new syndrome that either is closely related to the generalized hair follicle hamartoma (basaloid follicular hamartoma) or is a variant. The finding of generalized trichoepitheliomas with clinical and microscopic alopecia should alert one to the possibility of myasthenia gravis.

Adult↗
PubMed1996

Restoration of the continuity of dog ureter after resection of its 5 cm middle segment.

OBJECTIVE: To evaluate the restoration of the ureter of the dog after resection of a 5 cm-long middle segment. MATERIALS AND METHODS: Eight dogs underwent resection of the middle segment of the ureter, after which a 6-8 F Bard ureteric stent modelling catheter was inserted into both remaining portions of the ureter for 3 months. One month after removal of the stent the animals were killed and their ureters examined both grossly and microscopically. Paraffin-embedded sections were subjected to microscopic and immunohistochemical studies. RESULTS: The continuity of the ureter was restored but the reconstructed segment was narrowed to a variable extent. The wall of the ureter was lined by normal urothelium but consisted of fibrous connective tissue which failed to produce a regular coat. The reconstructed segment showed no smooth muscle cells (negative staining with azan and a negative reaction with monoclonal antibodies against desmin). A few smooth myocytes were found only at the border with intact portions of the ureter. CONCLUSIONS: The surgical procedure resulted in the restoration of ureteric continuity by repair and not by regeneration of its wall.

Animals↗