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Biomedical subjects

R Levy

Publications and source records attributed to R Levy.

At least 721 records · Page 40Linked to original sources
PubMed1981

Reactivity of monoclonal antibodies against human leucocyte antigens with lymphocytes of non-human primate origin.

The phylogenetic distribution of antigens present on human lymphocytes was investigated by incubating human or simian cells with murine anti-human monoclonal antibodies and then determining the level of reactivity with a radiolabelled anti-murine IgG reagent. The monoclonal antibodies used were specific for a T-cell antigen, lymphoid and lymphoid:myeloid antigens, Ia antigens, and beta 2 microglobulin. The cells examined included B- and T-lymphoblastoid cell lines and fresh peripheral blood lymphocytes separated by sheep erythrocyte rosetting into T-cell and non T-cell fractions. Results of these studies showed that the antibodies gave complete cross-reactivity with gorilla and chimpanzee cells while B-cell lines of orangutan origin had lost lymphoid and beta 2 microglobulin markers. Gibbon cells and cells of Old World and New World monkeys reacted strongly only with monoclonal antibodies against Ia antigenic determinants. These Ia antigens were found on the non T-cell fraction of fresh peripheral lymphocytes, on B-cell lines and on some virus induced T-cell tumour lines. Immunoprecipitation analysis using the anti-Ia antibodies showed a degree of molecular diversity on owl monkey and marmoset cells compared to the Ia antigens associated with human cells.

Animals↗
PubMed1981

Protective immunity against murine candidiasis elicited by Candida albicans ribosomal fractions.

Candida albicans ribosomes were prepared from mechanically disrupted cells through differential centrifugation and purification in a sucrose-ammonium sulfate solution. The ribosomes were analyzed chemically and physically and exhibited characteristics of eucaryotic ribosomes (78S). ICR female mice were immunized with two subcutaneous inoculations, 2 weeks apart, of 100 microgram of ribosomes (expressed as ribosomal protein). Immunized mice were challenged either intraperitoneally or intravenously with a lethal dose of live C. albicans cells. The 31-day survival rate of immunized mice challenged intraperitoneally was 64% (mean value) versus 27% in controls; in intravenously challenged mice the survival rate of the immunized animals was about 60%, with no survivors among the controls. In intravenously challenged mice, incomplete Freund adjuvant enhanced the protection elicited by the ribosomes. Protection by ribosomal immunization was obtained against challenge doses causing chronic and acute infection.

Animals↗
PubMed1981

Use of thallium-201 redistribution scintigraphy in the preoperative differentiation of reversible and nonreversible myocardial asynergy.

Thallium-201 (201Tl) redistribution scintigraphy might differentiate reversibly from nonreversibly asynergic myocardial segments and thus predict the response of these segments to coronary artery bypass grafting (CABG). To test this hypothesis, 25 consecutive patients undergoing CABG, preoperative stress-redistribution 201Tl scintigraphy, and both pre- and postoperative resting equilibrium radionuclide ventriculography were evaluated. For both types of scintigraphic study, each patient was imaged in the same three views. Because of the effects of CABG on septal motion, this region was considered separately. Postoperative improvement was noted in 54% of 72 preoperative asynergic segments. Improvement was common not only in hypokinetic but also in akinetic and dyskinetic segments, and occurred in a similar proportion of studies performed early (less than 2 weeks) or late (3-6 months) after CABG. Thallium-201 redistribution scintigraphy was highly predictive of the pattern of postoperative asynergy: The redistribution pattern was normal in 90% of segments with reversible asynergy and abnormal in 76% of segments with nonreversible asynergy. The presence or absence of pathologic Q waves was less sensitive in this differentiation. Septal segments, however, frequently demonstrated abnormal wall motion postoperatively, despite normal 201Tl redistribution scintigraphy. Resting left ventricular ejection fraction (LVEF) was generally unchanged postoperatively, but in some patients with multiple areas of reversible asynergy it did improve. Thus, 201Tl redistribution scintigraphy appears to reliably distinguish viable from nonviable asynergic myocardial zones, and predicts the response of these segments to CABG.

Coronary Artery Bypass↗
PubMed1981

Extrapyramidal reactions in Asians.

The authors studied systematically whether 20 Asian patients were more vulnerable to the acute extrapyramidal side effects of neuroleptics than were 20 black and 40 white patients. They found that extrapyramidal reactions were more frequent in the Asian patients and that the difference was statistically significant.

Adult↗
PubMed1981

Computed tomography and the outcome of affective disorder: a follow-up study of elderly patients.

Forty-one subjects from an earlier study, who had undergone computed tomography (CT) during their in-patient care for affective disorder, were followed up clinically for a minimum of one year. Mortality at two years was also determined, and comparisons made with 50 age-matched controls. Those with affective disorder showed a higher mortality than controls, but the difference just failed to reach significance. Within the affective group, however, mortality was significantly higher in patients who had previously shown ventricular enlargement on CT, confirming our earlier suggestion that these patients might have constituted a distinct subgroup. Failure of the affective group to improve performance on a simple cognitive test at follow-up was related to persisting depression. These and other findings are discussed.

Aged↗
PubMed1981

Antibodies to herpes simplex virus in human gingival fluid.

Antibodies to herpes simplex virus were found by immunofluorescent techniques in the gingival fluid of 84.0% of the persons tested. A mixture of IgG and IgA antibodies was demonstrated in 52.3% of the specimens while in 47.7% only IgG antibodies were found. Neutralization of herpes simplex virus infection in Vero cells by the gingival fluid was also demonstrated. No correlation between recurrences of herpes infection and the type of antibodies produced could be established.

Adult↗
PubMed1981

Follow-up observations on the effect of human leukocyte interferon in non-Hodgkin's lymphoma.

Follow-up data for 11 patients with non-Hodgkin's lymphoma treated with partially purified human leukocyte interferon is presented. The interferon preparation used was 0.1% pure and treatment consisted of 5 x 10(6) U given intramuscularly twice daily for 60 injections. One complete, three partial, and three minimal responses were observed in five of seven evaluable patients with nodular non-Hodgkin's lymphoma. Duration of response appears to be from 6 to 12 mo. One patient achieved a second partial response on retreatment with interferon in spite of having received chemotherapy in the interval between interferon treatments. No responses were seen in three patients with rapidly progressive diffuse histiocytic lymphoma. Dose-limiting toxicity is leukopenia, which necessitated modification or cessation of treatment in three patients. Nonhematologic toxicities consisted of fever, malaise, arthralgia, and loss of appetite. In conclusion, interferon has activity against non-Hodgkin's lymphoma, and prior treatment with chemotherapy does not preclude a response to interferon.

Adult↗
PubMed1981

Characterization of antigenic determinants on human myeloid colony forming cells with monoclonal antibodies.

Immunologic characterization of myeloid progenitor cells (CFUGM) provides a new dimension for identification and separation of this hemopoietic cell population from other cells within marrow and peripheral blood. Monoclonal antibodies against human anti Ia-like (HLA-DR) determinants and against T lymphocytes were utilized to more precisely define the cell surface antigenic structure of human CFUGM. Complement-mediated cytotoxicity testing demonstrated the presence of HLA-DR antigens and absence of a T lymphocyte antigen on the clonogenic CFUGM. Similar degrees of cytotoxicity were noted for B lymphocytes and CFUGM using anti HLA-DR monoclonal antibodies. Our studies with the anti T lymphocyte antibody suggest that T lymphocytes may be selectively removed from marrow cells without depletion of myeloid precursor cells.

Antibodies, Monoclonal↗
PubMed1981

The use of a monoclonal anti-idiotype antibody to study the biology of a human B cell lymphoma.

Immunoglobulin was obtained from the tumor cells of a patient with nodular lymphoma by hybridization to mouse myeloma cells. The human immunoglobulin secreted by these hybridoma cells was used as an immunogen to make murine monoclonal antibodies. Antibodies specific for idiotype, mu heavy chain and lambda light chain, were produced. One anti-idiotype antibody was used to document that idiotype-positive cells and low levels of 19S IgM idiotype were present in the patient's blood. The levels of each were found to correlate with the patient's disease activity. The monoclonal anti-idiotype was effective in eliminating idiotype-positive cells in vitro by solid phase absorption or by complement-mediated cytotoxicity. The anti-idiotype was also used to analyze the host's immunologic response to his own tumor idiotype. There was neither a detectable anti-idiotype antibody response produced in vivo nor a detectable population of T cells that expressed idiotype of could bind idiotype.

Animals↗
PubMed1981

In vivo effects of murine hybridoma monoclonal antibody in a patient with T-cell leukemia.

A murine monoclonal antibody directed against a normal T-cell differentiation antigen was given to a patient with adult T-cell leukemia. Immunofluorescence staining showed increased amounts of this antigen on the patient's leukemia cells. Using a competition radioimmunoassay, free antigen was not detectable in the serum prior to therapy. Two courses of in vivo therapy were given using a 1-mg dose. Each produced a prompt and dramatic fall in WBC with return to pretreatment levels over the ensuing 24 hr, a pattern similar to that seen with leukopheresis. After the first dose of antibody, circulating free antigen became detectable in the serum and a transient decline in creatinine clearance was noted. A 5-mg dose of antibody given at that time was ineffective, presumably because it was blocked by free antigen. Antigenic modulation by leukemia cells was found transiently following each course of antibody. A weak and clinically insignificant host antimouse antibody response was found 5 days after the first treatment. The patient tolerated antibody therapy without difficulty. Monoclonal antibodies offer promise as an immunotherapeutic approach to cancer but problems encountered here must be addressed.

Aged↗
PubMed1981

Definition of the high-risk acute lymphoblastic leukemia patient by immunological phenotyping with monoclonal antibodies.

An accurate method of classification of the surface membrane characteristics of blast cells from patients with acute lymphoblastic leukemia would allow a more definitive study of the nature of this disease. Monoclonal antibodies have been produced to the surface antigens of leukemic blasts form a patient with high-risk acute lymphoblastic leukemia. Two antibodies of interest were obtained from this immunization. These two, in combination with a monoclonal antibody with anti-Ia specificity, have been used to obtain surface phenotypes for patients with childhood acute lymphoblastic leukemia. Preliminary results indicate that the definition of a high-risk group, using these antibodies, possible.

Acute Disease↗
PubMed1981

Fatal aplastic anemia due to indomethacin--lymphocyte transformation tests in vitro.

Although indomethacin has been implicated as a possible cause of aplastic anemia on the basis of a few clinical observations, its role has not been definitely established. A case of fatal aplastic anemia is described in which no drugs other than allopurinol and indomethacin were given. Indomethacin was first given four weeks prior to the onset of symptoms. A positive lymphocyte transformation test with indomethacin in vitro further substantiates the potential role of this drug in causing aplastic anemia in a susceptible patient. Fortunately, this seems to be a very rare complication.

Aged↗
PubMed1981

Carcinoma of the cervix in Newark, New Jersey, 1970-76. A very low in situ: invasive ratio.

Both blacks and whites in Newark had significantly lowered incidences of in situ cervical cancer as compared to the Third National Cancer Survey (TNCS) population. In contrast, Newark blacks' invasive cancer rates were higher than those found in any individual geographic area surveyed in TNCS except for Minneapolis as compared to Newark whites, who had lower rates than all individual TNCS areas except Colorado and San Francisco. Newark blacks had a relative risk of 4.0 for invasive cancer as compared to Newark whites, whereas the corresponding relative risk for blacks versus whites in the TNCS population was 2.0. Newark blacks and whites together had the lowest in situ invasive ratio as compared to women in other parts of the United States. The invasive cancer incidence and mortality rates for both Newark blacks and whites were significantly higher than in the Surveillance, Epidemiology and End Results (SEER) population, but incidence:mortality ratios for Newark and SEER were not different. The most likely explanation for the low in situ rates and high invasive rates among Newark blacks is their failure to obtain Papanicolaou (Pap) smears. The low in situ rate among Newark whites in the absence of a high invasive rate is difficult to explain. It seems that the problem among blacks can be alleviated by the widespread use of Pap smears, which reduce the frequency of invasive cancer and the associated mortality.

Adolescent↗
PubMed1980

Inhibition of lymphoma hybrids by human interferon.

A set of stable mouse-human hybrids was constructed from the neoplastic lymphocytes from a patient with nodular lymphoma and from another with chronic lymphocytic leukaemia. Both patients had shown a clinical response to human leucocyte interferon. The same interferon preparation inhibited the growth rate of 14 out of 17 established hybrid cell lines. This system provides evidence of a direct growth inhibitory effect of interferon on neoplastic B lymphocytes. Such a system could be used to predict the sensitivity of a patient's tumour before therapy.

Aged↗
PubMed1980

Immunologic phenotype in 30 patients with diffuse large-cell lymphoma.

Frozen sections of 30 diffuse large-cell ("histiocytic") lymphomas that had arisen in both nodal and extranodal sites were stained with immunoglobulin light-chain and heavy-chain reagents, with nonoclonal antibodies to THAT HAD ARISEN IN BOTH NODAL AND EXTRANODAL SITES WERE STAINED WITH IMMUNOGLOBULIN LIGHT-CHAIN AND HEAVY-CHAIN REAGENTS, WITH MONOCLONAL ANTIBODIES TO T and B-cell antigens, and with an esterase marker for macrophages. Fourteen lymphomas expressed immunoglobulin light chains and were shown to be monoclonal; F(ab')2 fragments were sometimes necessary to demonstrate their monoclonal nature. Mu (IgM) was the most frequently expressed heavy chain, but in many patients other heavy chains were found. None of the lymphomas stained with T-cell antibodies or the esterase; 15 did not stain for immunoglobulin, but 13 of these 15 did express Ia antigen. These immunologic markers identified eight different phenotypes. Retrospective clinical analysis of the patients suggested that those who were immunoglobulin-positive had more advanced disease and shorter survival, but confirmation of the clinical relevance of immunologic phenotype will require prospective studies.

Adult↗