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L M Weiss

Publications and source records attributed to L M Weiss.

At least 289 records · Page 16Linked to original sources
PubMed1989

Pathologic features of prognostic significance in adrenocortical carcinoma.

There are currently no well-established pathologic prognostic factors helpful in distinguishing low versus high grade adrenocortical carcinomas. The effect of 11 pathologic parameters on survival was investigated in 42 cases of adrenocortical carcinoma. Only one variable, mitotic rate, had a strong statistical association with patient outcome. The 21 patients with carcinomas with greater than 20 mitoses per 50 high power fields (hpf) had a median survival of 14 months, whereas the 21 patients with carcinomas with less than or equal to 20 mitoses had a median survival of 58 months (p less than 0.02). The presence of atypical mitoses, capsular invasion, tumor weight greater than 250 g, and size greater than 10 cm each showed a marginal statistical association with poor survival (p less than 0.06), whereas other features assessed, such as nuclear grade, presence of necrosis or of venous or sinusoidal invasion, character of the tumor cell cytoplasm, or architectural pattern, showed no statistical significance in predicting survival. It is proposed that adrenal cortical carcinomas with greater than 20 mitoses be designated high grade, whereas tumors with less than or equal to 20 mitoses be designated low grade.

Adolescent↗
PubMed1989

Analysis of lymphoepithelioma and lymphoepithelioma-like carcinomas for Epstein-Barr viral genomes by in situ hybridization.

Lymphoepithelioma of the nasopharynx has a strong association with Epstein-Barr virus (EBV). To test the hypothesis that lymphoepithelioma-like carcinomas occurring at other sites are also associated with EBV virus, we used in situ hybridization to analyze 20 cases of lymphoepithelioma and histologically similar lesions and five basaloid squamous cell carcinomas for evidence of EBV genomes. EBV genomes were demonstrated in six of six lymphoepitheliomas of the nasopharynx but in none of five basaloid squamous cell carcinoma. Only one of 14 lymphoepithelioma-like carcinomas was found to contain EBV genomes. The single positive lymphoepithelioma-like carcinoma occurred in the lung of an Asian patient, suggesting that ethnic or geographic influences may be important in determining whether EBV is associated with these nonnasopharyngeal neoplasms. Despite their histologic similarity, most lymphoepithelioma-like carcinomas probably have a different pathogenesis from nasopharyngeal lymphoepithelioma.

Adult↗
PubMed1989

Viral infections.

Explore the source record for details and available documents.

Heart Transplantation↗
PubMed1989

Detection of clonal T-cell receptor gene rearrangements in the peripheral blood of patients with mycosis fungoides/Sezary syndrome.

Involvement of the peripheral blood in mycosis fungoides/Sezary syndrome (MF/SS) has a significant impact upon prognosis, but it is often difficult to distinguish circulating cells of MF/SS from atypical reactive lymphocytes. We compared the standard morphologic method of identifying leukemic cells, the Sezary preparation, to a genotypic method using Southern blot analysis of T-cell receptor gene rearrangements in concurrent blood samples. We studied 26 MF/SS patients, five of them in remission, together with five controls from cases of various non-MF/SS skin diseases. Six of 26 MF/SS patients had morphologically atypical circulating leukocytes (3%, 4%, 5%, 14%, 16%, 19%). Seven of 26 MF/SS patients had clonal T-cell receptor gene rearrangements, including the four patients with the greatest percentages of atypical cells and three patients lacking atypical cells. Six of seven patients had skin disease at the time of sampling, including three with erythroderma, two with generalized thick plaques, and one with generalized patches, while one patient was in clinical remission. All five controls lacked morphologic and genotypic evidence of atypical or clonal T-cells. Relative to genotyping, in our series the Sezary preparation was less sensitive and less specific. There were three apparent false negative results in the Sezary preparations, and two potential false positive (patients with 3% and 4% atypical leukocytes); however, there was agreement between the two techniques in most cases. We conclude that gene rearrangement studies may provide an effective test with which to assess the peripheral blood of MF/SS patients.

Blotting, Southern↗
PubMed1989

Small lymphocytic lymphoma.

The clinical course of 54 patients with small lymphocytic lymphoma (SL) was reviewed. The majority of patients had disseminated lymphoma at the time of diagnosis; 14 patients (26%) presented with Ann Arbor stage I and II disease. Five- and 10-year survival for all patients was 76% and 49%. The only clinicopathologic features identified that predicted a shortened survival were the presence or absence of systemic (B) symptoms (15% v 63% at 10 years, P = .01) and a diffuse rather than pseudofollicular nodal architecture (47% v 87% at 10 years, P = .04). Initial bone marrow involvement was not an adverse prognostic factor for patients who presented with stage III and IV disease. Ten patients developed a marked lymphocytosis consistent with progression to a leukemic phase (chronic lymphocytic leukemia [CLL]). These ten patients had a median initial lymphocyte count of 2,790, compared with 1,580 for those patients who did not progress to CLL (P = .0001). Developing CLL did not adversely affect survival (P = .48). Thirty-seven patients were treated with various combinations of radiation and chemotherapy; 17 patients received no initial therapy. Ten-year freedom from relapse (FFR) for stage I and II patients treated with irradiation was 80% and 62%; FFR for stage III and IV treated patients was 11%. Despite the marked differences in FFR, no statistically significant difference in survival could be demonstrated between the various stages. Selected patients with advanced SL received no initial therapy; these patients had a 10-year survival that was not statistically different from the immediately treated stage III and IV patients. Patients with stage I and II SL should be treated with irradiation; prolonged FFR and possibly cure of the disease can be achieved in these patients.

Actuarial Analysis↗
PubMed1989

Numbers of host "helper" T cells and proliferating cells predict survival in diffuse small-cell lymphomas.

Diffuse small-cell lymphomas of B-lineage comprise a group of immunophenotypically related lymphoid malignancies that display variable clinical aggressiveness. We compared a variety of clinical, pathologic, and immunologic characteristics of 64 B-lineage diffuse small-cell lymphomas to patient survival in an effort to define prognostically relevant subtypes of these neoplasms. Neither clinical parameters nor histological subclassification correlated with patient outcome. In contrast, three immunologic features of these lymphomas showed a statistically significant relationship with actuarial survival. Neoplasms that manifested greater than or equal to 25% Ki-67+ cells (proliferation-associated antigen), less than 25% Leu 4+ cells (pan-T antigen), or less than 15% Leu 3+ cells (helper/inducer T-subset antigen) were associated with significantly decreased patient survival as compared to neoplasms with the reverse phenotype (P = .02, P = .003, P = .0005, respectively). Leu 3 findings were of particular importance in initial biopsies (P = .0007), while the Ki-67 findings were significant regardless of time of biopsy (P = .01 for biopsies at diagnosis and P = .004 for other biopsies). These data indicate that immunologic analysis can demonstrate subsets of diffuse small-cell lymphoma with different biologic potential, and suggest that such analysis be included in the routine work-up of patients with this type of neoplasm.

Adult↗
PubMed1989

The expression of a metallothionein-ovine growth hormone fusion gene in transgenic mice does not impair fertility but results in pathological lesions in the liver.

The physiological effects of high serum levels of ovine GH (oGH) were studied in three generations of transgenic mice carrying a metallothionein 1-(MT)oGH fusion gene. Livers of mice expressing oGH were enlarged, irrespective of the level of serum oGH detected. In mice expressing high levels of oGH, direct measurements of hepatocytes in liver sections revealed that cell and nuclear size were abnormally large. Hepatocytes of different transgenic mice varied from 1.4-2.2 times normal size and hepatocyte nuclei varied from 1.7-2.4 times normal size. In addition, intranuclear inclusions were observed in hepatocytes of transgenic mice and their presence was always associated with high serum levels of oGH. In contrast to female transgenic mice containing mouse MT-human, rat, or bovine GH fusion genes female mice containing the MT oGH fusion gene were fertile and their pituitary glands showed synthesis of GH.

Animals↗
PubMed1989

Effect of verapamil on the development of chronic experimental Chagas' disease.

In previous work, we have shown that the chronic administration of verapamil, a calcium channel blocker, ameliorated the mortality, pathology, and biochemical alterations associated with acute murine Chagas' disease. To extend these studies to an established chronic model, C3H/Hej mice were infected with the Sylvio X10/4 clone. This clone does not cause symptomatic acute disease but does induce cardiac pathology incorporating several pathological features of human chagasic cardiomyopathy. Cardiac pathology was assessed at 60, 90, and 180 days postinfection. There was a significant decrease in the degree of inflammation and fibrosis in the group infected and treated with verapamil. Myocardial beta-adrenergic adenylate cyclase (AC) activity was determined 180 days postinfection. In the infected group not treated with verapamil, there was no significant change in the maximum rate of conversion of ATP to cAMP (Vmax) or in the concentration of agonist giving 50% of Vmax (apparent Kact) for isoproterenol (ISPN)-dependent AC activation. The increase in Vmax for ISPN determined in the presence of 5'-guanylylimidodiphosphate (Gpp[NH]p) was consistently lower in infected than in uninfected mice, suggesting that infection altered the potential synergistic activation of AC by the guanine nucleotide. In the infected group treated with verapamil, there was a slight increase in the Vmax for ISPN. However, there was a marked enhancement of the synergistic contribution of Gpp(NH)p. These observations suggest that verapamil had preserved that aspect of the AC complex mediating guanine nucleotide sensitive activation of AC. Collectively, the observations in the acute and chronic models of murine Chagas' disease suggest that verapamil may be a useful adjunct in treatment.

Adenylyl Cyclases↗
PubMed1989

In situ demonstration of Epstein-Barr viral genomes in viral-associated B cell lymphoproliferations.

Thirteen cases of benign and malignant Epstein-Barr viral (EBV)-associated B cell lymphoproliferations were examined by in situ hybridization studies performed on formalin-fixed, paraffin-embedded tissue sections. EBV nucleic acids were identified in a minority of lymphoid cells in five of six cases of benign infectious mononucleosis studied in tonsil or lymph node specimens. No evidence of EBV was found in two splenectomy specimens from patients with infectious mononucleosis. EBV nucleic acids were identified in one case of fatal, infectious, mononucleosislike immunoblastic proliferation, and were especially concentrated in areas where there were sheets of immunoblasts associated with necrosis. EBV nucleic acids were identified in all four cases of EBV-associated post-transplant lymphoproliferations, including three cases of non-Hodgkin's lymphoma in which a majority of the neoplastic cells contained EBV nucleic acids.

Adolescent↗
PubMed1989

SUP-HD1: a new Hodgkin's disease-derived cell line with lymphoid features produces interferon-gamma.

A new cell line, SUP-HD1, was established from the pleural effusion of a patient with nodular sclerosing Hodgkin's disease (NSHD). The SUP-HD1 cells had the characteristic morphology of Reed-Sternberg cells and contained acid phosphatase and nonspecific esterase. The cells lacked the Epstein-Barr virus (EBV) genome and reacted with monoclonal antibodies (MoAbs) against CD15 (Leu-M1), CD25 (Tac), CD71 (OKT9), Ki67, and HLA-Dr. However, the SUP-HD1 cells were nonreactive with MoAbs that specifically identify T lymphocytes, B lymphocytes, and macrophage/myeloid cells. Karyotype analysis of the cell line showed clonal abnormalities involving 1p13, 7p15, 8q22, and 11q23, chromosomal locations, at which breakpoints have been reported in HD. Southern blot analysis demonstrated rearrangement of the immunoglobulin heavy chain and kappa light chain genes as well as the gene for the beta chain of the T-cell receptor (TCR). Transcriptional analysis showed expression of RNAs for kappa light chain, interferon-gamma (IFN-gamma), and interleukin-2 receptor (IL-2R) but not IL-2. The SUP-HD1 cells lacked cytoplasmic and surface immunoglobulin heavy chain, but a small amount of cytoplasmic kappa light chain was detected. The presence of nuclear factor kappa B (NF kappa B), a B-lymphocyte-associated transcription factor, was demonstrated in stimulated and unstimulated cells. In addition, the SUP-HD1 cell line, produced IFN-gamma, a T-lymphocyte-associated lymphokine. Based on these data, the SUP-HD1 cells appear to be aberrant lymphocytes with characteristics of both activated B and T lymphocytes. Elaboration of lymphokines such as IFN-gamma by the malignant cells may represent one explanation for the unique clinical and pathologic features of HD.

Adult↗
PubMed1988

Utility of combining antigranulocyte with antileukocyte antibodies in differentiating Hodgkin's disease from non-Hodgkin's lymphoma.

The authors have reviewed their experience using the antigranulocyte marker, anti-Leu-M1, in combination with the antileukocyte marker, PD7/26, applied to paraffin sections of malignant lymphomas difficult to subclassify using morphologic criteria. The study group consisted of 73 lymphomas; 53 cases of Hodgkin's disease and 20 cases of non-Hodgkin's lymphoma. Leu-M1 was expressed by the Reed-Sternberg and Hodgkin's cells in 33 (62%) of the cases of Hodgkin's disease. The Reed-Sternberg and lymphocytic and histiocytic (L&H) cells in four cases of lymphocyte-predominant Hodgkin's disease were Leu-M1 negative. The Reed-Sternberg cells and L&H cells expressed leukocyte common antigen, utilizing the monoclonal antibody PD7/26, in seven (13%) of the 53 cases including the four cases of lymphocyte-predominant subtype (three nodular, one diffuse). The Reed-Sternberg-like cells in four (20%) of the cases of non-Hodgkin's lymphoma were stained by anti-Leu-M1 whereas, in 12 cases (60%) these cells were stained by PD7/26. The combination of anti-Leu-M1 and PD7/26 provided more useful information than that provided by anti-Leu-M1 alone by providing immunologic support for the diagnosis of lymphocyte-predominant Hodgkin's disease and by identifying cases which stained with neither antibody. The authors interpret the immunologic findings in the latter cases as equivocal. These studies were most helpful in cases with many atypical cells and provided unequivocal support for the diagnosis of Hodgkin's disease in six of 11 cases of the "syncytial variant," a form of the nodular sclerosing type characterized by cohesive aggregates of Reed-Sternberg cells and lacunar variants, not uncommonly misdiagnosed using only morphologic criteria.

Adult↗
PubMed1988

Isospora belli infection: treatment with pyrimethamine.

Isosporiasis is an uncommon but important diarrheal disease of humans that, like cryptosporidiosis, is life-threatening in patients with the acquired immunodeficiency syndrome (AIDS). Isospora belli infection responds rapidly to therapy with trimethoprim-sulfamethoxazole, but patients with AIDS have a high rate of adverse reactions to this therapy. The cases of two patients with AIDS, sulfonamide allergy, and I. belli infection are reported. They were treated successfully with pyrimethamine alone, 75 mg/d, and recurrence was prevented with daily pyrimethamine therapy, 25 mg/d. In patients with AIDS with sulfonamide allergy or intolerance, pyrimethamine alone seems to be a reasonable alternative therapy for I. belli infection.

Adult↗
PubMed1988

Expression in non-Hodgkin's lymphoma of the bcl-2 protein associated with the t(14;18) chromosomal translocation.

For many non-Hodgkin's lymphomas, the bcl-2 gene has been implicated as a likely proto-oncogene, since it is consistently located at or near the breakpoint sites of t(14;18) chromosomal translocations. To define the role of the protein product of the bcl-2 gene in lymphoid cancers, we used anti-bcl-2 antibodies to perform immunohistochemical studies of frozen sections of 136 tissue specimens affected by lymphoma or non-neoplastic lymphoid disorders. Immunoreactive bcl-2 protein was observed in the neoplastic cells in almost all the follicular lymphomas, whereas no bcl-2 protein was detected in follicles affected by non-neoplastic processes or in normal lymphoid tissue. Every tumor with molecular-genetic evidence of t(14;18) translocation expressed detectable levels of bcl-2 protein, regardless of whether the breakpoint was located in or at a distance from the bcl-2 gene. These data show consistent expression of a proto-oncogenic protein in a large proportion of non-Hodgkin's lymphomas and provide further support of a role for bcl-2 in the pathogenesis of all lymphomas with the t(14;18) karyotypic abnormality. Increased expression of bcl-2 after t(14;18) translocations may be a specific marker for B-cell cancers, and demonstration of the protein with use of anti-bcl-2 antibodies could be useful in the diagnosis of many non-Hodgkin's lymphomas.

B-Lymphocytes↗
PubMed1988

Renal cell carcinoma. Prognostic significance of morphologic parameters in 121 cases.

Morphologic parameters were correlated with survival in 121 renal cortical neoplasms including 116 carcinomas and five oncocytomas. An increasing nuclear grade was generally correlated with a significant decrease in disease-free survival although no statistical difference was found between nuclear Grade 1 and 2 tumors. Similarly, a higher stage at diagnosis predicted a shorter disease-free survival. Renal vein invasion adversely affected prognosis only for high nuclear grade carcinomas. Papillary and spindled carcinomas, independent of nuclear grade, were associated with a significant decrease in disease-free survival compared to tumors with a solid pattern. Patients with large neoplasms (greater than 10 cm) had a significantly worse disease-free survival than patients with tumors 10 cm or less. The prognostic significance of tumor cell type is less clear. Patients with oncocytomas had the best disease-free survival compared with patients with tumors of other cell types. However, the difference in survival was not statistically significant for low-grade tumors, suggesting that nuclear grade rather than cell type may be the more important determinant.

Adenoma↗
PubMed1988

Nodular and diffuse types of lymphocyte predominance Hodgkin's disease.

The nodular form of lymphocyte predominance Hodgkin's disease has been shown to be immunophenotypically distinct from the histologically diffuse form and from other types of Hodgkin's disease. We undertook a clinicopathological study of 73 cases to determine whether any clinical differences between the nodular and diffuse subtypes could be discerned. Patients with the diffuse form (n = 41) tended to have a course similar to that of other types of Hodgkin's disease; there were few relapses and only two deaths due to Hodgkin's disease. In contrast, patients with the nodular form (n = 32) had significantly more relapses, which were independent of stage or treatment and equally distributed up to 10 years after initial therapy. Despite the frequent relapses, patients with the nodular form had an indolent course, and there was only one death due to Hodgkin's disease. There were seven fatal second cancers and two non-neoplastic treatment-related deaths, equally distributed between the nodular and diffuse groups. We conclude that nodular lymphocyte predominance Hodgkin's disease may have important clinical as well as immunophenotypic differences from other forms of Hodgkin's disease, and that patients with this condition should be followed carefully because of the possibility of late relapse.

Adolescent↗
PubMed1988

Human thymomas: evidence of immunohistologically defined normal and abnormal microenvironmental differentiation.

Fifteen human thymomas were analyzed by immunoperoxidase studies on frozen and paraffin-embedded tissue sections in an attempt to identify the existence of immunologically defined microenvironments. All nine lymphocyte predominant thymomas contained a predominance of lymphocytes bearing the phenotype of cortical thymocytes and dendritic Class II major histocompatibility complex antigen-positive epithelial cells, thus defining cortical-like microenvironments. Medullary-like foci were also seen in all of these cases. Minor phenotypic abnormalities in Leu-2 and -3 antigen expression were seen in three cases. In contrast, the two epithelial predominant thymomas and four mixed thymomas all exhibited features of aberrant microenvironmental differentiation, with only two cases showing demarcation into cortical and medullary foci. A lack of Class II major histocompatibility complex antigens was associated with a decrease in the lymphoid populations and an increase in Leu-1 antigen expression by T cells of otherwise normal cortical phenotype when lymphocytes were present. In contrast, lack of Class I antigen on epithelial cells was not associated with any abnormality in lymphocyte phenotype or microenvironmental organization. We document for the first time abnormal microenvironments in thymomas that may offer insights into understanding normal thymic differentiation.

Antibodies, Monoclonal↗