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PubMed1990

Free alpha subunit of the pituitary glycoprotein hormones. Measurement in serum and tissue of patients with pituitary tumors.

A solid-phase radioimmunoassay was developed that measures the free alpha subunits of pituitary glycoprotein hormones (alpha PGpHs) and has negligible cross-reactivity with the intact hormones (less than 0.014% for thyroid-stimulating hormone [TSH], less than 0.1% for human chorionic gonadotropin [hCG], 0.8% for luteinizing hormone [LH], and 2.0% for follicle-stimulating hormone [FSH]). The assay is standardized with the alpha subunit of hCG but also reacts well with the alpha subunits of the other glycoprotein hormones (84% for alpha TSH, 77% for alpha FSH, and 64% for alpha LH). Concentrations as low as 0.3 micrograms/L can be reliably measured, and the 97.5% reference range in 27 healthy adults, including postmenopausal females, is less than or equal to 1.2 micrograms/L. Elevated preoperative alpha PGpH concentrations were found in 45 (9.4%) of 479 sera from patients with pituitary adenoma and 3 (4.5%) of 66 patients with nonadenomatous sellar lesions. Postoperative alpha PGpH levels were lower in 30 of 39 adenoma patients and 2 of 3 nonadenoma patients. In five (1%) of the patients with pituitary adenomas, alpha PGpH was the only elevated serum hormone marker. Serum values of alpha PGpH correlate weakly with alpha subunit immunocytochemical staining--95% of those with negative staining have normal alpha PGpH values, but only 18% of those with positive staining have elevated alpha PGpH values.

Adenoma↗
PubMed2000

Phakomatous choristoma: a case report and review of the literature.

Phakomatous choristoma is a rare congenital lesion of the eyelid that can be clinically and/or histologically mistaken for a cyst, cutaneous adnexal neoplasm, or an ocular adnexal oncocytoma. Only 13 such cases have been previously described, mostly in the English language ophthalmic literature. Zimmerman reported the first case in 1971 and proposed the lesion to be of lenticular anlage origin, a theory that has been widely accepted. We report an additional case occurring in an 8-week-old male infant with a firm nodule of the right lower eyelid that was present since birth. A 15 x 12 x 2 mm circumscribed solid nodule with a homogenously white cut surface was surgically excised. Histologically, this lesion was comprised of cuboidal cells forming cystically dilated and irregularly branched ducts and cords within a densely fibrotic stroma. Also present were eosinophilic basement membranelike material, psammoma body-like calcifications and intraluminal degenerated ghost cells. The immunohistochemical profile of the epithelial cells included strong immunoreactivity for vimentin, focal weak staining for S-100, and negative staining for cytokeratin, epithelial membrane antigen, synaptophysin, and chromogranin. The irregularity of the ducts and cords of epithelial cells within the densely fibrotic stroma resembled an infiltrative neoplasm of cutaneous adnexal or lacrimal duct origin. However, the site of involvement, the peculiar basement membrane material, ghost cells, and immunohistochemical profile were features that helped to distinguish phakomatous choristoma from an infiltrative carcinoma. The correct identification of this lesion is essential to avoid an aggressive surgical excision, thus sparing the eyelid and lacrimal system. The purpose of this article is to bring attention to this rare entity, because it has not been described in either the dermatology or dermatopathology literature and furthermore, is not mentioned in any of the major dermatopathology texts.

Choristoma↗
PubMed2007

Metastatic hidradenocarcinoma with demonstration of Her-2/neu gene amplification by fluorescence in situ hybridization: potential treatment implications.

A 44-year-old man was referred for a right chest nodule of 3 months duration. A 'benign' nodule had been excised from this location 8 years prior. On examination, palpable nodes were noted in the right axilla. Radiographic studies were significant only for right axillary lymphadenopathy. Histologically, a nodular dermal proliferation composed of poorly differentiated epithelioid cells in nests and focally forming ducts with pseudopapillary architecture comprised the primary tumor. Features of a clear cell hidradenoma were noted focally. Immunohistochemical (IHC) analysis revealed reactivity for HMW cytokeratins, CK5 and CK7, p53, p63, CEA (focal), androgen receptor, EGFR, estrogen receptor (ER), MUC5AC, and strong/diffuse membranous staining for Her-2/neu. Negative stains included villin, TTF-1, CDX2, S-100 protein, vimentin, gross cystic disease fluid protein 15 (GCDFP-15), mammoglobulin, and MUC2. A wide local excision and axillary node dissection was performed. Metastatic tumor involved nine of 28 nodes. Interphase fluorescence in situ hybridization (FISH) demonstrated chromosomal amplification of the Her-2/neu locus within the tumor and a nodal metastasis. The patient has completed adjuvant and radiotherapy, including trastuzumab, and is asymptomatic. We believe this to be the first demonstration of Her-2/neu amplification in a malignant skin adnexal tumor. In analogy to breast carcinoma, these findings suggest the applicability of trastuzumab for patients with metastatic adnexal carcinomas demonstrating Her-2/neu amplification.

Adenoma, Sweat Gland↗
PubMed2000

Overexpression of vascular endothelial growth factor is responsible for the hematogenous recurrence of early-stage gastric carcinoma.

Vascular endothelial growth factor (VEGF) is crucial for angiogenesis in various malignant tumors. However, it is still unclear whether VEGF is responsible for hematogenous metastasis after the curative resection of gastric carcinoma. In the present study, we evaluated the relevance of VEGF expression to the hematogenous recurrence of stage 1 or 2 primary gastric adenocarcinoma. Among 530 patients, 11 (2.1%) had hematogenous recurrence. Clinicopathological variables were compared between these 11 patients (group R) and 88 patients without intramucosal carcinoma who survived for more than 5 years (group S). Microvessel density (MVD) was assessed immunohistochemically along with VEGF protein expression in all patients from group R and 21 randomly selected patients from group S. There were significant differences in age, tumor size and VEGF expression in tumor tissue between the groups. Positive staining for VEGF protein was observed in all patients of group R, of whom 6 had strongly positive staining. On the other hand, 11 out of 21 patients in group S had positive staining and it was weak in all cases. Both the positive and strongly positive rate were significantly higher in group R than those in group S. There was no significant difference in MVD between the 2 groups (17.7 +/- 11.09/field in group R vs. 14.8 +/- 10. 27/field in group S) and no significant correlation between VEGF expression, MVD and venous invasion, though a weak correlation between the intensity of VEGF staining and MVD was observed (negative staining 12.1 +/- 10.51; weakly positive 16.67 +/- 10.41; strongly positive 19.7 +/- 9.97). Our results suggest that overexpression of VEGF, and not MVD or venous invasion, plays an important role in the hematogenous recurrence of curatively resected gastric carcinoma.

Adult↗
PubMed1994

Immunohistochemical evidence that human pterygia originate from an invasion of vimentin-expressing altered limbal epithelial basal cells.

The goal of this study was to determine the cell origin of human pterygia. In order to determine the origin of these cells, longitudinal cryostat sections through five primary and two recurrent pterygia were studied immunohistochemically by finding limbal basal stem cell staining patterns as defined by monoclonal antibodies AE1 (staining positive) and AE5 (staining negative). In addition, sections were stained with antivimentin antibody. Altered limbal basal cells invading normal cornea along the basement membrane were identified in seven human pterygia with these specific monoclonal antibodies. A group of limbal basal cells (vimentin and AE1 positive) was always present between the dissolved edge of Bowman's layer and vascularized conjunctiva which contained goblet cells. Scattered patches of cells staining positive with both vimentin and AE5 (in addition to their AE1 staining) were also found in conjunctival epithelium growing on corneal basement membrane adjacent to the migrating limbal cells, indicating local infiltration by the altered limbal basal cells. This same pattern was also found in recurrent pterygia. Based on this data we propose that the pathogenesis of pterygia is due to a normal stationary parental limbal epithelial basal cell becoming altered and giving rise to a zone of motile daughter cells, the pterygium cells, which leave the limbal region and migrate as a group centripetally along the corneal basement membrane dissolving Bowman's layer. Since these altered limbal basal cells are found at the microscopic advancing edge over Bowman's layer with no fibroblast mass under them, the pterygium cell apparently precedes the rapid growth of the fibroblasts from the stroma.(ABSTRACT TRUNCATED AT 250 WORDS)

Basement Membrane↗
PubMed1995

[A case of angiosarcoma with renal failure caused by recombinant interleukin-2 (rIL-2) and non-steroid anti-inflammatory drug (NSAID)].

A 77-year-old man was diagnosed to have diabetes. He was hospitalized for appetite loss, weight loss (6 kg/3 months) and right femoral pain. An abnormal shadow was noted on chest X-P. On admission, he was alert and there were no abnormal physical findings except limitation in the range of motion in the right lower extremity. His femoral pain was treated by a non-steroid anti-inflammatory drug (NSAID). Right femoral bone biopsy revealed angiosarcoma and staining for factor VIII, with negative staining for epithelial membrane antigen on enzyme assay. Therefore, he received systemic administration of recombinant interleukin-2 (rIL-2). rIL-2 was administered intravenously twice daily at a dose of 40 x 10(4) JRU. The total dosage of rIL-2 amounted to 1200 x 10(4) JRU, but renal failure deteriorated and he died on the 50th hospital day of his second admission. Combination of rIL-2 and NSAID may cause progression of nephropathy.

Aged↗
PubMed1998

[Placental site trophoblastic tumor: a study of clinicopathologic features and differential diagnosis].

OBJECTIVE: To study the clinicopathologic features and differential diagnosis of placental site trophoblastic tumor (PSTT). METHODS: 5 PSTT cases were studied and compared with 10 choriocarcinoma cases and 2 exaggerated placental site (EPS) cases by light and electron microscope examination and immunohistochemical staining. RESULTS: PSTT occurs in reproductive women and often following term deliveries. Amenorrhea and or vaginal bleeding are common presenting symptoms. The serum levels of hCG are often slightly or moderately elevated. Microscopically, PSTT is composed of only one kind of trophoblast cell, displaying extensive invasion of myometrium and vessels without obvious hemorrhage and necrosis. Mitotic figures are not common. Ultrastructure shows that the tumor cells contain prominent paranuclear filaments. Immunohistochemical reaction reveals positive staining for hPL and mostly negative staining for hCG. CONCLUSION: PSTT is a rare trophoblastic tumor with unique microscopic, ultrastructural and immunohistochemical features which can help to differentiate them from other trophoblastic diseases.

Choriocarcinoma↗
PubMed2000

[The status of protein P16 and P53 in the surgical margins of laryngeal carcinoma and the association with local recurrence].

OBJECTIVE: To assess the status of P53 and P16 of surgical margins in laryngeal carcinoma and the association with the local recurrence following surgical treatment METHODS: The status of P53 and P16 of surgical margins in laryngeal carcinoma was studied using immunohistochemistry (IHC) staining method in 100 cases of laryngeal carcinoma. Fifty-two of them had recurrent tumors while 48 cases were free of local recurrence after 5-year follow up. The original tumor sites and T stages, which bear important influence over the risk of local recurrence, were strictly matched between the two groups, and the ages and preoperative doses of radiation were also considered. RESULTS: The percentage of local recurrence was 85% in these patients who showed positive staining for P53 and simultaneous negative staining for P16 in both the cancer tissues and the surgical margins. No association was found between the expression of P53 and P16 and the clinical types or T stages. CONCLUSION: The status of P53 and P16 in combination demonstrated by IHC technique in surgical margins of laryngeal carcinoma may predict the possibility of local recurrence.

Adult↗
PubMed1985

[Histopathological diagnosis of early stages of myocardial infarction--applications of the improved hematoxylin basic fuchsin picric acid (HBFP) staining method to human autopsy hearts].

In the early stage of myocardial infarction, the mortality rate is very high and its diagnosis is difficult not only clinically but also pathologically. Hematoxylin basic fuchsin picric acid (HBFP) staining method has been controversial on reliability for the morphologic diagnosis of early stages of myocardial ischemia. We applied HBFP staining method improved hematoxylin staining and differentiating solution to 42 human autopsy hearts. In eight cases with diagnosed acute myocardial infarction clinically and/or pathologically and 4 cases that suffered from post-infarction angina and died suddenly at home or outdoors, HBFP stain showed positive. Other cases, including non-ischemic heart disease and sudden death due to non-cardiac disease and ventricular arrhythmia, were HBFP staining negative. In conclusion, improved HBFP staining method is useful in identifying early myocardial ischemia and extent of early infarcts, and explaining for sudden death due to re-attack of myocardial infarction.

Adolescent↗
PubMed1985

Immunohistochemical localization of keratin in head and neck neoplasms and normal tissues.

Immunohistochemical localization of keratin antigens using keratin antisera and the immunoperoxidase technique have been shown to be helpful in identifying certain epithelial cells. Our study was designed to evaluate the application of this technique to head and neck neoplasms and normal tissues using two keratin antibody preparations. Our data indicate that the keratin antibodies stained normal epithelial structures in the head and neck except for cells with active secretory functions such as mucus, cerumen, or salivary secretion. Neoplasms of the head and neck showed keratin antibody staining for epithelial neoplasms and negative staining for mesenchymal neoplasms. The immunohistologic demonstration of keratin is useful in distinguishing undifferentiated or poorly differentiated epithelial malignancies from sarcomas or lymphomas and demonstrating myo-epithelial cells in salivary neoplasms.

Animals↗
PubMed1985

Ultrastructural localization of human platelet thrombospondin, fibrinogen, fibronectin, and von Willebrand factor in frozen thin section.

We have investigated the localization of thrombospondin (TSP), fibrinogen, fibronectin, and von Willebrand factor in human platelets by transmission electron microscopy of antibody-stained ultrathin frozen sections. In negatively stained thin sections, alpha granules were identified on the basis of their smooth, roughly spherical shape, size, single limiting electron-lucent 100 A membrane, and frequent presence of electron-dense nucleoid. In contrast, mitochondria exhibited characteristic double membranes and cristae. Sections were separately stained with affinity-purified polyclonal antibodies to these proteins as well as with three monoclonal anti-TSP antibodies. Antibody specificity was documented in radioimmunoassays, by immunofluorescent cross-blocking, and by staining of bands of appropriate mobility in Western blots of whole platelets. Bound antibody was visualized using a 5-nm colloidal gold-avidin conjugate. In resting cells, staining of virtually all alpha granules was observed for all four proteins. In contrast, consistent staining was absent from other organelles, including plasma membranes, mitochondria, and vacuolar structures that may represent the open canalicular system.

Animals↗
PubMed1988

[Lectin-binding sugar chain in bladder tumors].

We studied the lectin binding patterns of 40 initial superficial and 10 subsequent invasive bladder tumors by the avidin-biotin-peroxidase complex (ABC) method using the following biotin-labeled lectins: PNA, DBA, UEA-I, BS-I, ConA and WGA. We observed the relationship between lectin binding and subsequent course of initial superficial tumors, grade and stage (T). DBA or WGA staining tumors and Con A negative tumors revealed no recurrence or superficial recurrence. Low grade tumors were DBA or BS-I positive and high grade tumors were ConA positive. Low staging tumors possessed DBA or WGA positiveness and high staging tumors had ConA positiveness. From these results we considered that negative staining of WGA or DBA, or positive staining of ConA was a change accompanying the malignant potentiality.

Adult↗
PubMedDate not supplied

Fine needle aspiration biopsy of hepatocellular carcinoma. Value of immunocytochemical and ultrastructural studies.

Over three years, 365 fine needle aspiration biopsies (FNABs) of the liver were performed at Ottawa Civic Hospital. Fifty-nine percent of these aspirates were positive for malignancy. A diagnosis of hepatocellular carcinoma (HCC) was made in 20 liver aspirates. The initial light microscopic diagnoses of HCC were confirmed by immunocytochemical and/or electron microscopic (EM) studies in 16 aspirates. Canalicular pattern of staining with antibody to carcinoembryonic antigen (CEA), positive staining with anticytokeratin AE3 and negative staining with anticytokeratin AE1 supported the diagnosis of HCC. Although alpha-fetoprotein (AFP) expression is relatively specific for HCC, it was positive in only 44% of cases, and the staining was usually focal. EM study confirmed the diagnosis of HCC in seven cases. Based on our findings and published reports, we use a diagnostic panel of antibodies to CEA, AFP and anticytokeratins AE1 and AE3, and/or EM study when there is a suggestion of HCC cytologically or clinically.

Biomarkers, Tumor↗
PubMed2006

Pseudoactinomycotic radiate granules of the gynaecological tract: review of a diagnostic pitfall.

The filamentous bacterium actinomyces can cause serious gynaecological tract infections, including pelvic inflammatory disease (PID) and tubo-ovarian abscess. Thus, definitive diagnosis of actinomycotic granules (AMGs) in gynaecological specimens is clinically important. Non-infectious pseudoactinomycotic radiate granules (PAMRAGs) can mimic the microscopic appearance of AMGs. PAMRAGs may be more common than actinomycotic infections in specimens from patients using intrauterine devices and may be seen in patients with PID. Although the composition and aetiology of PAMRAGs is unclear and variable, a panel of histochemical stains can aid in diagnosis. On haematoxylin and eosin (H&E) stained sections, AMGs show as distinct granules with basophilic peripheral radiating filaments and a dense central eosinophilic core, whereas H&E stained sections of PAMRAGs feature refractile granules with irregular club-like peripheral projections and no central dense core. The filaments of AMGs are Gram positive on Brown and Brenn (B&B) stain and are highlighted with Gomori methenamine silver stain (GMS). They stain negatively with a modified acid fast bacillus (AFB) stain, aiding in the distinction of actinomyces from nocardia. PAMRAGs show negative or non-specific staining with B&B, GMS, and AFB stains. Therefore, knowledge of these staining properties and the distinguishing characteristics of PAMRAGs and AMGs enables recognition of this important diagnostic pitfall.

Actinomycosis↗
PubMed1999

Age-related hippocampal changes in Bcl-2:Bax ratio, oxidative stress, redox-active iron and apoptosis associated with aluminum-induced neurodegeneration: increased susceptibility with aging.

We propose that aging is an important factor in the susceptibility of neurons to oxidative stress and to subsequent apoptosis. In the present report we demonstrate that aged rabbits treated intracisternally with aluminum maltolate exhibit intense intraneuronal silver positivity indicative of the formation of neurofilamentous aggregates, together with oxidative stress. These changes occur in the CA1 region of the hippocampus as well as in cerebral cortical areas. Apoptosis, measured by the TUNEL in situ technique, colocalizes with oxidative stress. Young animals treated with aluminum show few of these alterations, while age-matched controls are essentially negative. Further studies on the time course of these and related changes demonstrate that oxidative stress and redox-active iron accumulation in hippocampal neurons occur very rapidly, within a period of 3 hours, and increased in intensity at 72 hours. Changes suggestive of apoptosis are seen by 24 hours and are pronounced at 72 hours. In aged animals there is an initially intense immunopositivity at 3 hours for Bcl-2, with negative staining for Bax. By 72 hours, when apoptosis is strongly evident, Bcl-2 is negative and Bax strongly positive. In contrast to the aged rabbits, young animals treated similarly with aluminum exhibit much less oxidative stress with no apoptosis, and maintain Bcl-2 immunopositivity and negative Bax staining. Our findings strongly support the key role that oxidative damage plays in the process of neurodegeneration and in the increased vulnerability to aluminum-induced injury in the aged animal. These are novel observations which may have important implications for aiding in our understanding of the pathogenesis of neurodegeneration occurring in Alzheimer's disease.

Aging↗
PubMed1997

Keyhole limpet hemocyanin (KLH), I: Reassociation from Immucothel followed by separation of KLH1 and KLH2.

Studies of keyhole limpet hemocyanin (KLH) normally require purification of functional complexes directly from living animals. An alternative procedure is described wherein a commercial preparation of KLH which is fully dissociated into its subunits (Immucothel, biosyn Arzneimittel GmbH) is reassociated in the presence of a high concentration of calcium and magnesium. The reassociation products, when observed by electron microscopy, consist of didecamers, multidecamers and flexible tubules of varying length. The two forms of KLH described previously and designated KLH1 and KLH2, are present in the reassociated mixture as homo-oligomers/polymers and can be separated by selective dissociation of the KLH2 by treatment with 1% ammonium molybdate-0.2% PEG at pH 5.7, followed by gel filtration chromatography in this solution. In addition to discrete elution peaks containing didecameric KLH1 and dissociated subunits of KLH2, a leading peak contains a tubular/polymeric form of KLH1, not previously described. Under negative staining in conditions designed specifically for the creation of 2-dimensional crystals on mica (the negative staining-carbon film procedure), this tubular form of KLH1 can be transformed into a larger diameter multidecameric form, again not previously described for KLH1. The purified KLH2 peak is indistinguishable from subunit material prepared from living animals. This, Immucothel appears to provide a standardized source of subunits suitable for biochemical and structural studies on the two types of KLH.

Animals↗
PubMed1982

Surface activation of carbon film supports for biological electron microscopy.

The effect of glow-discharging on naked carbon-filmed grids has been evaluated. The effect of different locations of the grids within a DC discharge, operated in the normal glow, was analyzed by applying various biological specimens to the grids. Two locations were found to give consistent results: (a) in Crookes dark space, particulate specimens, negatively stained, spread evenly--suggesting a new negative surface charge of the support; (b) below the anode, nucleic acids, selectively (positively) stained, appeared as well spread filaments, indicating a net positive surface charge.

DNA↗
PubMed2001

Ku protein and DNA strand breaks in lip glands of normal and primary Sjögren's syndrome subjects: lack of correlation with apoptosis.

UNLABELLED: The aim was to examine tissue expression of Ku protein in lower lip salivary gland (LSG) biopsies from cases of primary Sjögren's syndrome (SS) and from normal subjects. METHODS: immunohistochemistry was used with antibodies to Ku70/86 and also Ki67, PCNA and p53. In addition, the Klenow method was applied in order to detect evidence of apoptosis. Sections of hyperplastic tonsil served as additional controls. RESULTS: in normal controls, LSG acinar cells stained negatively whereas LSG excretory duct cell nuclei stained positively with Ku and Klenow and occasionally with PCNA but negatively with Ki67 and p53. In LSG focal sialadenitis of SS cases, some lymphocytic cells showed staining with Ku, Ki67, PCNA, Klenow and p53. In addition to duct cell Ku and Klenow as well as PCNA staining which was not much different from normals, a few ductal epithelial and also mononuclear cells stained with p53. In focal sialadenitis, some acinar cells showed staining with PCNA as well as with Klenow. CONCLUSIONS: our findings in LSG biopsies of SS cases added little to an increased understanding about the pathogenetic mechanisms in the development of focal sialadenitis in SS. However, in normal LSG, ductal epithelial but not acinar cells seem to express a constitutively specific Ku protein and Klenow profile, suggestive of DNA strand breaks but not clearly associated with ongoing apoptotic events. It may reflect an enhanced stress response, which may be pathogenetically important in the early events of focal sialadenitis development in primary Sjögren's syndrome.

Antibody Specificity↗