LN-5 antibody against human macrophages cross-reacts with routinely processed human sebaceous glands.

LN-5 monoclonal antibody against human macrophages was found to selectively stain human sebaceous glands in formalin-fixed, paraffin-embedded skin samples. Undifferentiated sebocyte progenitors were negative, and only sebocytes from the onset of their differentiation revealed positive cytoplasmic immunofluorescence. Since there are very few selective and easy-to-use markers of sebaceous glands, LN-5 antibody can offer a simple and relatively specific way to detect human sebocytes from the onset of their differentiation in routinely processed material, both freshly prepared and archival.

Cyclin D1 and D3 expression in melanocytic skin lesions.

Cyclins, cyclin-dependent kinases, as well as proteins cooperating with them are responsible for cell cycle regulation which is crucial for normal development, injury repair, and tumorigenesis. D-type cyclins regulate G1 cell cycle progression by enhancing the activities of cyclin-dependent kinases, and their expression is frequently altered in tumors. Disturbances in cyclin expression were also reported in melanocytic skin lesions. The objective of the study was to evaluate the expression of cyclins D1 and D3 in common, dysplastic, and malignant melanocytic skin lesions. Forty-eight melanocytic skin lesions including common nevi (10), dysplastic nevi (24), and melanomas (14) were diagnosed by dermoscopy and excised. Expression of cyclin D1 and D3 was detected by immunohistochemistry and quantified as percentage of immunostained cell nuclei in each sample. In normal skin, expression of cyclins D1 and D3 was not detected. The mean percentage of cyclin D1-positive nuclei was 7.75% for melanoma samples, 5% for dysplastic nevi samples, and 0.34% for common nevi samples. For cyclin D3, the respective values were 17.8, 6.4, and 1.8%. Statistically significant differences in cyclin D1 expression were observed between melanomas and common nevi as well as between dysplastic and common nevi (p = 0.0001), but not between melanomas and dysplastic nevi. Cyclin D3 expression revealed significant differences between all investigated lesion types (p = 0.0000). The mean cyclin D1 and D3 scores of melanomas with Breslow thickness <1 mm and >1 mm were not significantly different. G1/S abnormalities are crucial for the progression of malignant melanoma, and enhanced cyclin D1 and D3 expression leading to increased melanocyte proliferation is observed in both melanoma and dysplastic nevi. In histopathologically ambiguous cases, lower cyclin D3 expression in dysplastic nevi can be a diagnostic marker for that lesion type.

[Histological examination of specimens obtained during autopsy of the exhumed corpse of general Wladyslaw Sikorski]. / Badanie histologiczne wycinków pobranych podczas sekcji ekshumowanych zwlok generala Wladyslawa Sikorskiego.

The authors present the results of histological examinations of tissue specimens obtained during autopsy of the exhumed corpse of general Wladyslaw Sikorski. In spite of the level of corpse decomposition, the connective tissue stroma was preserved in virtually every specimen.

Microvessel density and area in pituitary microadenomas.

Microvessel density (MVD) and area (MVA) were assessed in 53 clinically silent pituitary microadenomas and in surrounding normal pituitary tissue using CD34 immunostaining and digital image analysis system. Twenty-one microadenomas (40%) were avascular; in the others, both MVD and MVA were significantly lower than in the normal pituitary tissue. No significant differences in MVD and MVA were found between hormonally immunonegative and immunopositive tumors or between different hormonal subtypes of immunopositive microadenomas. In microadenomas and in normal pituitary tissue, MVD and MVA were not significantly influenced by age or sex. These results suggest that pituitary adenomas at early developmental stage are either avascular or significantly less vascular than normal pituitary tissue and that differences in vascularity of pituitary adenomas associated with the variables of sex, age, clinical presentation and immunohistochemical phenotype reported in the literature can evolve with tumor growth and possibly acquire statistical significance in large macroadenomas.

Development of mature lamellar bone with a hematopoietic compartment in an aortic valve homograft.

Two foci of mature lamellar bone with features of remodeling and with an adjacent hematopoietic compartment were revealed for the first time in an aortic valve homograft by hematoxylin and eosin staining and polarized light microscopy. The valve had been obtained originally from a 52-year-old non-beating-heart donor and implanted as 'fresh antibiotic-preserved' into the left ventricular outflow tract of a 21-year-old man, but was explanted after six years due to valvular insufficiency. The areas close to bone showed the presence of cells resembling osteoblasts, osteoclasts and degenerating chondrocytes. Von Kossa staining disclosed a small area of dystrophic calcification in the vicinity of one bone fragment, whereas the second fragment was accompanied by only weak, diffuse calcification. These findings shows that the formation of ectopic mature bone with secondary development of the hematopoietic compartment can occur in a relatively short time, and suggest that initiators of the process may be present in the grafted valve.

Incidence of pituitary necrotic lesions in autopsy material.

Pituitary necrosis is mostly a result of pituitary haemorrhage or infarct. The frequency of pituitary necrosis in the Polish population has not yet been investigated. Hence, the aim of this study was to estimate the incidence of pituitary necrotic lesions in forensic autopsy material and to assess possible correlations of pituitary necrosis with sex, age, other pituitary pathologies, endocrine disorders and atherosclerosis. Serial sections of 100 human pituitary glands stained with hematoxylin-eosin were examined microscopically. Pituitary necrosis was found in 19 cases (19%), all of them in persons aged > 40 years. The majority of the lesions had relatively large size, occupying 10-50% of the gland. According to family interviews, none of the subjects manifested any clinical symptoms related to pituitary insufficiency, hence al the detected cases can be regarded as subclinical. There was no association of pituitary necrosis occurrence with sex, other pituitary pathologies found upon autopsy, endocrine diseases or cause of death. Only correlations with age and atherosclerosis were statistically significant. This study has shown that subclinical pituitary necrosis is a relatively frequent phenomenon in elderly persons, probably resulting from age-related deterioration in the vascular status.

Macrophage-specific RAM11 monoclonal antibody cross-reacts with basal cells of stratified squamous epithelia.

RAM11 is a mouse monoclonal anti-rabbit macrophage antibody recognizing connective tissue and vascular (atheromatous tissue) macrophages. This study demonstrates a cross-reaction of RAM11 with an unknown antigen in rabbit normal epithelial cells. Formalin-fixed, paraffin sections of the New Zealand White rabbit normal skin, oral mucosa, esophagus, small intestine and lung were immunostained with RAM11 antibody followed by goat anti-mouse Cy-3-conjugated antiglobulin. RAM11-positive immunofluorescence was observed in basal layer cells of stratified squamous epithelia (skin, oral mucosa, esophagus). No RAM11 immunostaining was found in any cells of simple (intestinal, bronchial) epithelia. These findings show that basal cells of stratified squamous keratinized and non-keratinized epithelia of the rabbit express an antigenic epitope which is common with that of macrophage antigen recognized by RAM11 monoclonal antibody.

Increased incidence of pituitary microadenomas in suicide victims.

BACKGROUND: Current data suggest an influence of the hypothalamic-pituitary-adrenal axis on suicidal behavior. The frequency of pituitary adenomas in suicide victims has not yet been investigated. OBJECTIVES: The aim of this study was to assess whether the incidence of pituitary adenomas is correlated with suicide. METHODS: Serial sections of 151 human pituitary glands obtained upon autopsy were examined microscopically. The glands were collected from 70 suicide victims and 81 subjects whose deaths were classified as unexpected or accidental (nonsuicidal group). The sections were stained with hematoxylin-eosin and the presence of adenoma was confirmed by immunostaining for collagen III. RESULTS: In the suicidal group, pituitary microadenomas were found in 32 cases (47.7%), while in the nonsuicidal group microadenomas were detected in 15 cases (18.3%). The observed difference was statistically significant (p = 0.0003). The relative risk ratio of suicide in persons with pituitary adenomas was estimated at 1.9. Logistic regression analysis in a model controlled for age and sex showed that microadenomas constituted a unique risk factor in this model. The immunohistochemical phenotyping revealed a higher percentage of immunopositive (secreting) microadenomas in the nonsuicidal group as compared to the suicidal group (80.0 vs. 59.38%) and a predominance of growth hormone-secreting microadenomas in both groups. However, these differences as well as differences in the hormonal profiles of microadenomas between the groups were not significant. CONCLUSIONS: These results suggest that pituitary adenomas belong to suicide risk factors.