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B F Atkinson

Publications and source records attributed to B F Atkinson.

11 recordsLinked to original sources
PubMed1990

Monoclonal antibody-dependent, cell-mediated cytotoxicity against human malignant gliomas.

Two monoclonal antibodies (MAbs), IgG2a MAb ASHG4 and IgG2b MAb ASHE2, were produced in mice immunized with cultured human malignant glioma cells. Both MAbs bound strongly to the surfaces of long-term cultured glioma cells, and MAb ASHE2 also bound strongly to short-term cultured glioma cells. Sections of frozen glioma tissues bound both MAbs strongly, whereas normal brain tissues showed weaker reactivities, and tissues derived from carcinomas of various histological types were completely unreactive. Furthermore, the MAbs did not bind to peripheral blood cells or bone marrow cells. Although both MAbs bound to the same Mr 27,000-29,000 protein, they may detect different or overlapping epitopes on this antigen. Because MAbs ASHE2 and ASHG4 lysed cultured glioma cells with human peripheral blood lymphocytes as effector cells, they are promising reagents for approaches to immunotherapy of human malignant gliomas.

Antibodies, Monoclonal↗
PubMed1989

Monoclonal antibodies with cytotoxic reactivities against human gliomas.

Monoclonal antibodies (MAb's) reactive with human malignant glioma cells were derived from mice inoculated with cells from fresh glioma tissue. Seven MAb's were selected for study based on their high-level binding in immunoperoxidase and immunofluorescence assay to most of the glioma tissues derived from various patients and based on the absence of binding to normal bone marrow cells. Four of the seven MAb's did not bind to any of the four normal brain tissues tested, whereas three MAb's bound to one or two of these tissues. Two MAb's bound to the surfaces of cultured glioma cells in radioimmunoassay. One of these MAb's (AS-AY1, immunoglobulin (Ig)(G1) lysed cultured glioma cells with human lymphocytes or murine macrophages as effector cells; the other MAb (AS-AY2, IgM) was reactive in complement-dependent cytotoxicity assay. These two MAb's therefore seem especially promising reagents in approaches to immunotherapy of human malignant glioma.

Antibodies, Monoclonal↗
PubMed1988

Diagnosis of Pneumocystis carinii pneumonia by cytologic evaluation of Papanicolaou-stained bronchial specimens.

To evaluate the sensitivity and specificity of diagnosing Pneumocystis carinii pneumonia (PCP) by Papanicolaou-stained bronchial brushing and wash/lavage specimens obtained by fiberoptic bronchoscopy, the cytologic preparations and clinical records from 58 immunocompromised patients were reviewed. Bronchial brushings and wash/lavage specimens were examined using methenamine silver (Grocott) and Papanicolaou stains. Pneumocystis carinii pneumonia was recognized with Papanicolaou stain by identifying distinctive alveolar casts, which frequently contained collections of encysted sporozoites. Thirty cases of PCP were identified, and Grocott-stained bronchial wash/lavage specimens were positive in 29 instances (97%). Grocott staining of the transbronchial biopsy was positive for PCP in 18 of 22 specimens (82%). Bronchial brushings were insensitive, yielding a positive specimen in only 30% of cases of PCP. Alveolar casts of PCP were identified by Papanicolaou-stained slides of wash/lavage specimens in 83% of cases of Pneumocystis pneumonia. These proteinaceous alveolar casts were not seen in other pulmonary disorders. Encysted sporozoites were found in 56% of cases in which Papanicolaou-stained alveolar casts were identified. We conclude that the diagnosis of PCP can be made rapidly and reliably on the Papanicolaou-stained bronchial wash/lavage or bronchial brush specimens by detecting the characteristic alveolar casts, which contain P. carinii-encysted sporozoites. The presence of encysted sporozoites within alveolar casts is pathognomonic for PCP, and methenamine silver stains can be eliminated in those cases in which encysted sporozoites are identified.

Bronchoalveolar Lavage Fluid↗
PubMed1987

The fibrolamellar variant of hepatocellular carcinoma. Its association with focal nodular hyperplasia.

A case of fibrolamellar hepatocellular carcinoma (FL-HCC) associated with adjacent focal nodular hyperplasia (FNH) is described. These two regions were adjacent but distinct, both on gross and microscopic examination. Currently, it is unclear whether FL-HCC rarely arises in preexisting FNH, or whether FNH is a typical response to this vascular variant of hepatocellular carcinoma (HCC). The FNH region, which is peripheral, may be biopsied to exclude the underlying carcinoma, and thus lead to inadequate therapy. Previous reports of this association are reviewed.

Adult↗
PubMed1987

Purification and amino terminal sequencing of human melanoma nerve growth factor receptor.

The nerve growth factor (NGF) receptor, solubilized with Triton X-100 detergent, has been purified from human melanoma cell line A875. Purification to near-homogeneity was achieved by chromatography on wheat germ agglutinin-agarose, followed by immunoaffinity chromatography on Sepharose columns coupled with anti-NGF receptor monoclonal antibody (MAb). The purified receptor, a 75,000-dalton protein, retains the capacity to bind NGF as well as anti-receptor MAbs. Final purification was achieved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The sequence of amino acid residues at the amino terminus has been determined. Possible sequence homology between the NGF receptor and several other proteins is discussed. Using the purified receptor as immunogen, new MAbs to the NGF receptor have been produced. The NGF receptor was visualized by immunoperoxidase staining in tissue sections of dorsal root ganglia from monkeys.

Amino Acid Sequence↗
PubMed1985

An antimelanoma monoclonal antibody and the histopathology of uveal melanomas.

Monoclonal antibody ME491 identifies a cutaneous melanoma-associated antigen in formaldehyde-fixed, paraffin-embedded tissues. This antibody was applied to tissue sections from 79 cases of formaldehyde-fixed, paraffin-embedded uveal melanomas. Sixty-nine (87.3%) of the 79 cases showed staining by monoclonal antibody ME491, thus demonstrating an antigen shared by cutaneous and uveal melanomas. No relationship between the staining pattern and the patient outcome was detected. Twelve (85.7%) of the 14 cases in which balloon cells were present stained with the antibody. The antibody stained the long posterior ciliary nerve in 12 (38.7%) of 31 cases in which the nerve was present in tissue sections. The antibody cross reacted with the retinal pigment epithelium (16.5% of cases) and a variety of normal nonocular tissues.

Antibodies, Monoclonal↗
PubMedDate not supplied

Invasive cervical thymoma masquerading as a solitary thyroid nodule. Report of a case studied by fine needle aspiration.

A 49-year-old woman underwent fine needle aspiration (FNA) biopsy of a presumed thyroid nodule. The initial cytopathologic interpretation suggested a chronic lymphocytic thyroiditis or a malignant lymphoma. The examination of frozen sections during surgery also suggested the presence of a lymphoma. However, histopathologic examination of permanent sections showed the lesion to be an invasive ectopic lymphocyte-predominant thymoma adjacent to the thyroid. Immunoperoxidase staining of FNA cell block sections and permanent sections showed positivity for keratin, proving the epithelial nature of the elongated and spindle-shaped tumor cells. This case high-lights the need to be aware of unusual lesions that may occur in the area of the thyroid; recognizing the potential diversity of "thyroid" masses that ultimately prove to be of nonthyroid origin should aid in making the correct cytologic differential diagnosis and interpretation of FNA samples obtained from such masses.

Biopsy, Needle↗
PubMedDate not supplied

Melanuria.

The urinary cytologic findings in a patient with metastatic malignant melanoma, diffuse melanosis and melanuria are presented. The melanosis was diagnosed from the clinical appearance of a generalized slate-blue skin discoloration, which is probably caused by dermal deposition of excess melanin pigment. The melanuria was characterized microscopically by the presence of amorphous, dark-brown casts, which stained positively for melanin pigment, and numerous pigment-laden macrophages.

Back Pain↗
PubMedDate not supplied

Psammoma bodies in fine needle aspirate of the thyroid in lymphocytic thyroiditis.

Psammoma bodies are concentric, laminated microcalcifications that are regarded as nearly specific markers in the thyroid gland for the presence of papillary carcinoma. While psammoma bodies have been seen rarely in some benign thyroid diseases, there appear to be no reports of psammoma body formation in lymphocytic or Hashimoto's thyroiditis. We report a case of Hashimoto's thyroiditis in which psammoma bodies were identified in a fine needle aspiration specimen of the thyroid and in histologic sections of the right thyroid lobectomy; papillary carcinoma was not found in either specimen. We conclude that psammoma bodies may be seen in any benign process, such as nodular goiter or lymphocytic thyroiditis, that produces reactive papillary hyperplasia of thyroid epithelium, as well as in papillary carcinoma. However, the finding of psammoma bodies in a fine needle aspirate without corroborating cytologic evidence of papillary cancer is still an indication for surgical removal of the thyroid nodule since these structures are reliable markers for occult papillary carcinoma of the thyroid, despite the rarity of their formation in benign diseases.

Adult↗