Biomedical subjects

M S Diocee

Publications and source records attributed to M S Diocee.

6 recordsLinked to original sources

PubMed1993

Fine-needle aspiration biopsies of metastatic neuroendocrine tumors in liver: use of transmission electron microscopy and protein A gold technique in diagnosis.

Five fine-needle aspiration biopsies of liver were studied to evaluate the use of electron microscopy and protein A gold technique in the diagnosis of metastatic neuroendocrine tumors. All five cases had cytologic features suggestive of neuroendocrine tumors and neurosecretory granules on ultrastructural examination. The aspirates were stained by the immunoperoxidase technique and the postembedding protein A gold technique using the antibody to chromogranin A. Three cases were positive for chromogranin A by both immunoperoxidase and protein A gold techniques. Two cases were positive by protein A gold technique and negative by immunoperoxidase technique. Confirmation of neurosecretory granules by immunochemistry is ideal, since ultrastructurally they can be mimicked by other electron-dense inclusions. Advantage of the protein A gold technique is the use of the same material for both ultrastructural evaluation and the protein A gold technique.

Adult↗

PubMed1991

Angiosarcoma of the uterus: a case report.

We are reporting a case of angiosarcoma of the uterus in which the diagnosis was confirmed ultrastructurally by demonstration of Weibel-Palade bodies in the tumor cells. Only 10 cases of this entity have been previously documented in the literature.

Aged↗

PubMed1986

Nonsecretory parathyroid carcinoma of the mediastinum. Light microscopic, immunocytochemical, and ultrastructural features of a case, and review of the literature.

Nonsecretory parathyroid carcinoma is rare, particularly in extracervical sites. The authors present a case of a 51-year-old man with a large mediastinal mass that was found on a chest x-ray. Light and electron microscopy and immunohistochemical analysis of the resected tumor disclosed findings consistent with parathyroid carcinoma. Clinical and laboratory evaluations failed to reveal evidence of hyperparathyroidism. The nonsecretory state of the tumor was further supported by immunoreactivity for parathormone in tissue sections and, at the same time, normal levels of this peptide in serum. Partial shrinkage of the mediastinal mass occurred after 11 months of combined chemotherapy, with subjective improvement. A literature review of both secretory and nonsecretory parathyroid carcinomas was undertaken, revealing similar clinical features with regard to mean age, age range, and sex incidence among both groups.

Follow-Up Studies↗

PubMed1982

Transmission electron microscopy of horse embryos 3-16 days after ovulation.

The 23 embryos were obtained by flushing the reproductive tract. Though the general cytology was observed, most attention was given to the formation of the embryonic capsule. It first appeared as a thin uniform layer on the inner surface of the zona pellucida of embryos recovered from the uterus on Day 6. By Day 8 the capsule was about 1 micron thick and the zona pellucida had been shed. In fixed embryos of 11 days and over the capsule was 3 microns thick and had a finely stippled but otherwise homogeneous appearance.

Animals↗

PubMed1980

Distribution of neurofilaments in myelinated axons of the optic nerve of goldfish (Carassius auratus L.).

Neurofilaments were counted in myelinated axons of the optic nerve of goldfish which were acclimated to 5 degrees and 25 degrees C. The number of neurofilaments increases markedly with increasing axonal size; axons of less than 0.1 micrometer 2 in area contain between 25 and 60 neurofilaments, while in the larger axons of area greater than 1.0 micrometer 2 there are approximately 190. The densities of the neurofilaments in the small axons are noticeably higher than in the larger ones (507 and 160, respectively). A variety of fixation procedures i.e. osmium tetroxide (OsO4) in phosphate buffer, glutaraldehyde (4%) in phosphate buffer or in ethyleneglycol-bis-(beta-aminoethyl ether)-N,N'-tetraacetic acid (EGTA) and piperazine-N-N'-bis-(2-ethanesulphonic acid) (PIPES) and post-fixed with OsO4 had no effect on the numbers of neurofilaments relative to the size of axon. The anaesthetic MS-222 (tricaine methanesulphonate) likewise had no effect on the numbers of neurofilaments. It is proposed that temperature acclimation alters the axon diameter concomitant with an alteration in the number of neurofilaments to fit the new diameter of the axons.

Acclimatization↗

PubMedDate not supplied

Processing fine needle aspiration biopsies for electron microscopic examination. Experience implementing a procedure.

While processing needle rinses from fine needle aspiration biopsy material for electron microscopy, we experienced difficulties not fully outlined previously. Problems in preservation were traced to the time elapsed before glutaraldehyde was added to the needle rinse, which had been held in a physiologic transport medium; a tendency toward hypotonicity of the commercially prepared transport medium; and vigorous handling of the needle rinse. When these problems were dealt with, preservation improved dramatically. The problem of scanty material available for ultrastructural evaluation was dealt with by decreasing the number of smears made and filtering the needle rinse to capture tissue fragments. Implementation of the procedure required leadership, good communication, motivated cytotechnologists and cytopathologists, and continuous supervision and monitoring. In cases with adequately cellular well-preserved material available for electron microscopy, ultrastructural evaluation made a contribution of clinical value to the diagnosis in 48% of cases.

Biopsy, Needle↗