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Z Posalaky

Publications and source records attributed to Z Posalaky.

31 records · Page 2Linked to original sources
PubMed1980

Cell processes in basal cell carcinoma.

Three cell process types are described in basal cell carcinoma. The most abundant are thin processes resembling microvilli; thick processes, mesa-like structures often surmounted by desmosomes; and large bulging processes. Processes occur in the intercellular spaces, and are more numerous in spinocellular cells than in basaloid cells. Despite the abundance of processes in basal cell carcinoma, they do not usually penetrate the basal lamina border of the tumor. This behavior differs from more rapidly invasive squamous cell carcinoma where processes extend through the fragmenting basal lamina into the stroma.

Basal Cell Carcinoma↗
PubMed1980

Granulomatous hepatitis as a manifestation of quinidine hypersensitivity.

Histologic pictures have been conflicting in previous cases of quinidine-associated hepatitis. We report a case of reversible granulomatous hepatitis from quinidine hypersensitivity, with granuloma induction occurring within three days after readministration of quinidine. Fever, urticaria, and mild thrombocytopenia were associated clinical findings. Both light and electron microscopic study results are reported.

Biopsy↗
PubMed1979

Intercellular junctional specializations in human basal cell carcinoma. A freeze-fracture study.

Intercellular junctions of various types were found on the membrane fracture faces of human nodular basal cell carcinoma (BCC) cells. The junctional types represented include desmosomes, tight junctions, and gap junctions. A semiquantitative comparison of undifferentiated and differentiated nodular BCC showed that gap and tight junctions were observed on all exposed membrane fracture interfaces of the differentiated tumors, while only fifty six per cent of the membrane interfaces of the undifferentiated tumor exhibited similar junctional specializations. These membrane specializations may be a partial reflection of differentiation among the different types of BCC and their contribution to the less invasive character of nodular BCC cannot be ruled out.

Basal Cell Carcinoma↗
PubMed1979

Gap junctions between Sertoli and germ cells of rat seminiferous tubules.

Ultrastructural observations of rat seminiferous tubules show clearly the presence of plasma membrane junctions between Sertoli and germ cells in the basal and adluminal compartments. Results obtained from the freeze fracture and thin section techniques were correlated in order to elucidate the nature of these intercellular junctions. We suggest that these intercellular membrane specializations are gap junctions which occur within regions of plasma membrane that also exhibit adherens-like modifications.

Animals↗
PubMed1978

Neuroanatomical and electroencephalographic correlations in Sanfilippo syndrome, type A.

Waking and all-night-sleeping electroencephalographic recordings were obtained on a boy with Sanfilippo disease, type A. The most striking abnormalities were noted during sleep and included (1) lack of progression through normal sleep stages, (2) absence of vertex waves and normal sleep spindles, (3) inability to stage sleep by the usual criteria, and (4) an unusual alteration of low-amplitude (12 to 15 Hz) activity with generalized delta frequencies. Subsequently, neuropathological examination was performed. The electrophysiological phenomena may be correlated with severe cortical involvement.

Basal Ganglia↗
PubMed1978

Development of Sertoli cell junctions in vitro--a freeze-fracture study.

Seminiferous tubules of 1-day-old rats were maintained in organ culture for up to 40 days. Five classes of intercellular junctions between Sertoli cells were observed by the freeze-fracture method as the tissue aged: (a) typical gap junctions; (b) focal tight junctions; (c) macular tight junctions; (d) meandering tight junctions; and (e) extensive tight junctions. The relative proportions of these types of Sertoli cell junctions were quantitated as the organ cultures progressed. The junctional structures observed and classified in organ culture were identical to those seen in vivo, but the timing of their appearance and/or disappearance, as well as their relative proportions, was different from that observed in the developing animal. Extensive tight junctions, with numerous parallel strands, were observed in the 40-day cultures; however, their oblique orientation with respect to the myoid layer was in contrast to the parallel orientation observed in vivo.

Animals↗
PubMed1978

Pigmented penile papules with carcinoma in situ changes.

Benign appearing, multifocal, pigmented penile papules were found in three patients, showing the histopathological and electron microscopic changes of carcinoma in situ. Their clinical appearance, relation to other carcinoma in situ lesions, as well as possible pathogenesis are discussed.

Adult↗
PubMed1977

Intercellular junctional complexes of the rat seminiferous tubules: a freeze-fracture study.

This paper provides a description of the intercellular junctions in the rat testis, as observed using the freeze fracture technique. These intercellular junctions were categorized into four general types: Sertoli cell tight junctions, myoid cell tight junctions, gap junctions, and "heterogeneous junctions." The Sertoli cell tight junctions had a mean depth of 3.1 micron in the basal to apical direction, and contained 25 to 50 (average: 36) parallel rows of particulate sealing elements. The myoid cell tight junction was neither continuous nor extensive, but focal in nature. Interestingly the sealing elements of this junction, like those of the Sertoli cell tight junction, were quite particulate in nature. Typical gap junctions were observed between Sertoli cells where they were intercalated between the parallel rows of the Sertoli cell tight junction. The most interesting observation was the identification of gap junction-like structures, in various stages of formation, on germ cell membrane fracture faces, both in the basal and adluminal compartments. Lastly, the unusual "heterogeneous junction" was observed on large membrane fracture faces in close proximity to cells in the adluminal compartment, presumably between Sertoli cells. These junctions appeared to consist of both tight and gap junction elements.

Animals↗
PubMedDate not supplied

Electron microscopic identification of the colorectal origins of tumor cells in pleural fluid.

Cellular material from metastatic rectal and lung adenocarcinomas was recovered from pleural and pericardial fluids, respectively. It was examined by electron microscopy (EM) to determine if certain ultrastructural features, which are primarily prominent in colorectal adenocarcinomas, were maintained in the tumor cells in metastatic fluid. These features include the presence of microvilli with dense microfilamentous cores that extend deeply into the apical cytoplasm (cytoplasmic rootlets) and an abundance of glycocalyceal bodies. It was found that tumor cells from the patient with a primary rectal adenocarcinoma exhibited these critical distinguishing characteristics. The cells from the lung adenocarcinoma, while containing many well-developed microvilli, did not possess cytoplasmic rootlets or glycocalyceal bodies. In addition, and possibly of more diagnostic significance, is the observation that the presence of microvilli and cytoplasmic rootlets remained evident in tissue pieces and cell blocks initially processed in paraffin and then reembedded for EM.

Adenocarcinoma↗