The further localization of antibody on cemental tissue

In order to increase our understanding of the immunologic aspects of periodontal disease, three groups of extracted human teeth were evaluated for the presence of antibody on the cementum surface. Antibody was demonstrated by direct immunofluorescence using monospecific antibody with human alpha , gamma and upsilon chain activity. The cemental surfaces of teeth with no clinical evidence of periodontal disease or teeth with gingivitis demonstrated no antibody. On the other hand, teeth involved with severe periodontal disease demonstrated positive fluorescence on root surfaces within the pockets, indicating the presence of antibody. No fluorescence was seen below the deepest point of the pocket. Furthermore, we have been studying a component recovered from the surface of teeth exposed to a periodontal pocket. Inhibition studies between serum antibody, extracted antigen and the antigen and antibody on the tooth surface suggest that we are dealing with the same antigen-antibody complex in all cases.

Preparation of rat monoclonal antibodies to epitopes encoded by the viral oncogene (v-fms) of McDonough feline sarcoma virus

The McDonough strain of feline sarcoma virus (SM-FeSV) contains a viral oncogene, v-fms, transduced from cat cellular genetic sequences designated c-fms. Monoclonal antibodies reactive to antigenic determinants encoded by v-fms were prepared by immunizing rats with live, syngeneic SM-FeSV-transformed cells, and fusing splenic lymphocytes from a tumor-bearing animal with cultured rat myeloma cells. Culture supernatants from hybrids producing antibodies to epitopes encoded by v-fms were identified by immunoprecipitation of radiolabeled polypeptides from SM-FeSV-transformed mink cells. Four positive hybrids were cloned twice in soft agar, established as stable lines, and grown in defined serum-free medium to facilitate purification of homogeneous antibodies. The monoclonal antibodies were used to assay SM-FeSV-specific products by "immunoblotting" of electrophoretically separated proteins, and by fixed-cell immunofluorescence.

The inconsistent pattern of thallium defects: a clue to the false positive perfusion scintigram

Exercise thallium myocardial scintigrams were analyzed in 76 consecutive patients with documented normal coronary arteries to identify the factors associated with abnormal or "false positive" studies. The thallium scintigrams had been judged normal in 60 patients (79 percent) and abnormal in 16 (21 percent). Analysis of the location of thallium defects in the 16 patients with abnormal scintigrams revealed a pattern that was consistent with coronary artery disease in 5, including 4 with an abnormal left ventricle, and a pattern that was inconsistent in the other 11. In 9 of these 11 patients the pattern of defects suggested soft tissue attenuation, by the diaphragm in 2 and breast or adipose tissue in 7, whereas in the other 2 patients isolated apical defects were seen. Among exercise myocardial scintigrams performed in 68 randomly selected patients with abnormal coronary arteries, 6 (9 percent) were reported to be normal. In four patients with abnormal scintigrams, the diagnosis of coronary artery disease was based on an inconsistent pattern. In three of these the pattern was related to isolated apical defects and in one it was related to apparent soft tissue attenuation. "Consistent" scintigraphic defects, seen frequently in patients with normal coronary arteries, in whom they are usually associated with an abnormal left ventricle. In patients with normal coronary arteries, "inconsistent" thallium defects are probably related to soft tissue attenuation or to normal apical thinning. Although defects caused by isolated apical abnormalities and soft tissue attenuation are also seen in patients with coronary diseases and add somewhat to scintigraphic sensitivity, they are a rare cause of diagnostic scintigraphic abnormalities in patients with coronary disease. The incidence of false positive thallium scintigrams could be reduced and overall accuracy improved by careful attention to the pattern of thallium defects.

Paraplegia following intrathecal cytosine arabinoside

Paraplegia following prophylactic intrathecal cytosine arabinoside (Ara-C) is described in a patient with acute myelogenous leukemia in remission who received doses of 100 mg/m2/d for 5 consecutive days. Cerebrospinal fluid examination prior to the last dosage of cytosine arabinoside revealed a mononuclear pleocytosis and increased protein. The neurological manifestations developed within one week after the last dose of Ara-C and persisted for over 8 weeks. Administration of intrathecal Ara-C in the same dose over longer intervals within 3-5 days between consecutive doses resulted in mild, transient neurological symptoms (paresthesias) in only one of 30 patients so treated.

Observation of beta-hemolysis among three strains of Streptococcus mutans

Streptococcus mutans is normally alpha- or gamma-hemolytic on blood agar plates. However, three recently isolated S. mutans strains were observed to elicit beta-hemolysis. The production and nature of a hemolytic substance were studied.

Geographic dark posterior fundus patches

Nine cases of a newly recognized, probably not uncommon, anomaly of the retinal pigment epithelium have been observed over a four-year period. The lesions occur predominantly in black subjects. Some degree of hemoglobinopathy was present in all the black patients with geographic dark posterior fundus patches. Almost all of the patients were young (6 to 26 years old) but two were 50 years of age. In three patients the patches grew larger. They did not interfere with vision or visual fields and did not appear to be involved with vitreous abnormalities. Fluorescein angiography was normal. In three patients, an electroretinogram gave subnormal results to all stimulus intensities; it was normal in one patient.