Search PubMed⌕ Search

Biomedical subjects

H Stein

Publications and source records attributed to H Stein.

At least 307 records · Page 17Linked to original sources
PubMed1993

Cultured human NK cells express the Ki-1/CD30 antigen.

In this study we show that in vitro cultured human polyclonal NK cell lines and clones express the Ki-1/CD30 Hodgkin-associated antigen, identified by the BER-H2 monoclonal antibody. The percentage of BER-H2+ cells ranged from 19% to 67% in five polyclonal NK cell lines and was 31% and 20% in two NK clones. The intensity of BER-H2 mAb staining on cultured NK cells was remarkably lower than that found on the L540 Hodgkin's lymphoma cell line. Resting PBL populations that had been enriched for NK cells failed to react with the BER-H2 mAb. Western blot analysis performed on cell lysates from a polyclonal NK cell line and from the NK3.3 NK-like cell line revealed that BER-H2-reactive molecules consisted of two major bands of approximately 110 kD and 100 kD. Two bands displaying an identical electrophoretic mobility were also found in lysates of the L540 cell line. The BER-H2 mAb failed to inhibit the nonspecific activated killer activity of cultured NK cells against both K562 and MeWo tumour target cells. In addition, the BER-H2 mAb was unable to trigger the cytolytic activity of NK cells in a redirected killing assay. The observation that cultured human NK cells express the Ki-1/CD30 antigen may be of relevance for the possible lineage assignment of K11/CD30+ lymphoid cell neoplasia with unrearranged TCR genes.

Blotting, Western↗
PubMed1993

Comparison of computed tomography, endosonography, and intraoperative assessment in TN staging of gastric carcinoma.

From 1986 to 1990 a prospective comparative study was undertaken to compare the relative accuracy of computed tomography, endogastric ultrasonography, and intraoperative surgical assessment in evaluating the depth of invasion (T category) and involvement of lymph nodes (N category) of patients with gastric carcinoma. One hundred and eight consecutive patients, who were treated by total gastrectomy and previously evaluated with computed tomography, endogastric ultrasonography, and intraoperative surgical assessment, entered the study. Results (T and N category) were compared with those of histopathological staging (pT and pN category). T categories were correctly staged in 43% of cases with computed tomography, 86% with endogastric ultrasonography, and 56% with intraoperative surgical assessment. Computed tomography scanning correctly staged 51% of all N1 and N2 lymph nodes compared with 74% for endogastric ultrasonography and 54% for intraoperative surgical assessment. In general, computed tomography was more accurate for advanced stages of cancer and showed a tendency to overstage the T category and understage N category of gastric tumours. By contrast, endogastric ultrasonography was equally accurate for all T categories and showed an understaging for N categories. Intraoperative surgical assessment overstaged early T stages, understaged T4 tumours, and was equally accurate for all grades of N categories. Computed tomography scanning and intraoperative surgical assessment of T and N categories were of little value in staging of gastric carcinoma. Endogastric ultrasonography is more accurate than computed tomography scanning and intraoperative surgical assessment. Therefore endogastric ultrasonography should be introduced in the preoperative assessment of patients with gastric carcinoma.

Adult↗
PubMed1993

Plasma epinephrine appearance and clearance rates in fetal and newborn sheep.

Newborn plasma catecholamine levels are elevated compared to fetal life. Whether this reflects increased catecholamine secretion after birth or decreased clearance is not known. To determine the plasma appearance and clearance rates for catecholamines during the transition to postnatal life, we compared plasma epinephrine appearance and clearance rates in fetal sheep before birth and in newborns after delivery. Plasma epinephrine appearance and clearance rates were measured by radiotracer analysis in eight fetuses at 127 +/- 1 days of gestation and, after cesarean delivery, at 130 +/- 1 days of gestation. There was no difference in plasma epinephrine appearance rate during the fetal (26 +/- 4 ng.kg-1 x min-1) or newborn studies (31 +/- 5 ng.kg-1 x min-1). The fetal plasma epinephrine clearance rate (131 +/- 13 ml.kg-1 x min-1) was significantly higher than newborn plasma epinephrine clearance rate (40 +/- 3 ml.kg-1 x min-1). Thus fetal plasma epinephrine appearance rate is not different from appearance rate in the immediate newborn period when catecholamine levels are higher than during most other physiological circumstances. The increase in circulating catecholamine levels at birth is due in part to a significant decrease in clearance rate. It is likely that removal of the placental contribution to whole body clearance accounts for much of the difference observed in fetal and newborn clearance rates.

Animals↗
PubMed1993

Tumor viruses in CD30-positive anaplastic large cell lymphomas.

CD30+ anaplastic large cell lymphoma (ALCL) represents a novel lymphoma entity at the borderline between Hodgkin's disease and non-Hodgkin's lymphomas. Phenotypic, genotypic, and karyotypic analyses have shown that ALCL are heterogeneous in cellular origin, and may be conceived as malignancies derived from activated, mainly T- or B-lymphoid cells, in some instances with an immature genotype. Epstein-Barr virus genomes and gene products, most notably the transformation-associated latent membrane protein (LMP), have been detected in a proportion of cases, and some cutaneous ALCL proved to harbor complete or incomplete HTLV-1 proviruses. These findings suggest that both EBV and HTLV-I, which are powerful inducers of CD30 expression in lymphoid cells in vitro, may contribute to the pathoetiology of ALCL.

Aged↗
PubMed1993

Musculoskeletal manifestations of Crohn's disease.

The prevalence of musculoskeletal system complaint and involvement in a group of 54 Crohn's disease patients, with a follow-up of 2 to 40 years, was studied and compared to that of a control group of patients with a similar distribution of sex and age. Twenty-four (44%) with Crohn's disease complained of arthralgia in various joints, but only 7.4% had objective findings compatible with joint pathology such as swelling, tenderness, and decreased range of motion. None of them had any serological or radiological evidences of joint damage. No significant correlation was found between patients' complaints/physical signs and age, sex, duration, or severity of Crohn's disease or mode of medical or surgical treatment. In the control group, 46% complained of arthralgia in various joint. The differences in the percentages of arthralgia between the two groups was not significant, although they differed in location of the affected joint. In the Crohn's disease group, a significantly higher proportion of knee, hip, and wrist involvement was observed, while backache was very common in the control group. It is suggested that arthritis in patients with Crohn's disease is an uncommon finding and that arthralgia is just as prevalent as in a matched control group. The pathogenesis of arthralgia in such a condition may be caused by soft tissue involvement.

Adolescent↗
PubMed1993

Results of early and delayed surgical fixation of hip fractures in the elderly: a comparative retrospective study.

The postoperative course of 555 elderly patients with fractures of the femoral neck was reviewed. Of these, 89% were surgically treated within 24 hours following injury and the remaining within 2-7 days. The postoperative results of patients who underwent reconstructive surgery within 24 hours were significantly better than of those treated later. The overall immediate postoperative mortality in these surgically treated patients was 1.6%, whereas in 56 patients who were treated conservatively the mortality rate was 8.9%. This markedly low mortality was observed in spite of a high percentage of associated diseases in 71.2% of the surgically treated patients. These findings suggest that whenever possible, immediate or early reconstructive surgery of femoral neck fractures in the elderly is the preferred treatment of choice. Early surgical intervention should be pursued and performed following immediate medical evaluation, even in the presence of multiple associated diseases. The contraindication to surgical treatment must be well defined and kept to a bare minimum, since conservative treatment appears to bear a high mortality risk in geriatric patients.

Aged↗
PubMed1993

Epstein-Barr virus and CD30+ malignant lymphomas.

Phenotypic, genotypic, and karyotypic analyses have indicated that Hodgkin's disease and CD30+ anaplastic large cell lymphoma may be conceived as malignancies derived from activated, cytokine-producing lymphoid cells, in many instances with an immature genotype. Most recently, Epstein-Barr virus (EBV) genomes and gene products, most notably the transformation-associated latent membrane protein (LMP), have been detected in approximately 50 and 20% of the cases, respectively. These findings suggest that EBV may superimpose an activated phenotype on an immature lymphoid cell, contributing to the pathoetiology of sizable proportions of these CD30+ malignancies.

Antigens, CD↗
PubMed1993

Comparison of fluorescence polarisation immunoassay (FPIA) and high performance liquid chromatography (HPLC) methods for the measurement of flecainide in human plasma.

The precision and accuracy of HPLC and FPIA for the measurement of flecainide plasma levels were compared below, in and above the therapeutic range (200-1,000 ng/ml). Following a calibration crossover study, five standard plasma solutions of varying flecainide concentrations (SPS) and 99 flecainide containing plasma samples of 24 in-patients (IPS) were analyzed with both methods. The results show that within the range of approximately 500-1,500 ng/ml, the two methods did not differ in either precision (expressed as coefficient of variation, CV) or accuracy (expressed as relative error, RE). Close to the lower limit and below the therapeutic range however, HPLC provided greater precision and accuracy than FPIA.

Chromatography, High Pressure Liquid↗
PubMed1993

Evaluation of the use of tannic acid in preparation of the rabbit knee meniscus for scanning electron microscopy.

The femoral faces of medial and lateral menisci of the rabbit knee were structurally reinforced with tannic acid and studied using the scanning electron microscope. Significant improvement in preservation of the meniscal surfaces, as compared to previous studies, was brought about by the structural reinforcement technique. Menisci, although detacted from tibial plateaux, retained well their shape, dimensions, and microarchitecture. Differences in surface morphology between medial and lateral menisci and between longitudinal sectors on menisci were recorded. Appearances of surface irregulatities were reduced to a very low level, and the possibility that this minimum exists in situ is forwarded.

Animals↗
PubMed1992

Expression of p53 protein in invasive colorectal carcinomas of different histologic types.

BACKGROUND: This study was performed to determine whether morphologic differences of colonic cancer types can be related to different genotypes of these tumors. METHODS: Paraffin sections of 76 human invasive colorectal carcinomas were examined for the overexpression of p53 oncoprotein with the avidin-biotin complex-peroxidase staining procedure and CM-1 antiserum, which detects p53 protein in paraffin-embedded material. The tumors were categorized as mucinous (22 cases), most of which originated from adenomas, and nonmucinous, which were subdivided into carcinomas originating from adenoma-carcinoma sequence (ACS) (29 cases) and de novo (DN) carcinomas (25 cases). RESULTS: Nineteen DN carcinomas (76%), 21 ACS carcinomas (72%), and 8 mucinous carcinomas (36%) exhibited detectable amounts of p53 protein in the tumor cell nuclei. Strong overexpression of p53 protein coincided with a high percentage (> 40%) of stained nuclei in 40% of ACS and 48% of DN carcinomas versus 9% of mucinous tumors. The percentage of stained nuclei, intensity of staining, and distribution of the stained areas did not correlate with the grade of differentiation or the invasive edge of the tumors. Along with nuclear staining of the tumor area, a distinct perinuclear staining of normal epithelial cells adjacent to the tumor was observed in 48% of DN, 7% of ACS, and 9% of mucinous carcinomas. CONCLUSIONS: The current results, in combination with the recently published data on Ki-ras and c-myc alterations, indicate that mucinous carcinomas differ from nonmucinous colorectal carcinomas in their genetic lesions.

Adenoma↗
PubMed1992

[The Ilizarov apparatus in pseudoarthrosis of the long bones].

Distraction osteogenesis with the Ilizarov technique is effective in achieving bone healing in both atrophic and infected pseudoarthrosis. In 10 patients with atrophic and 14 with infected pseudoarthrosis treated by this method, solid bone union with reconstruction of anatomical limb length was achieved in all except 1. They ranged in age from 16-80, with a mean of 44. The mean treatment time was 9.4 months for the femur, 4.5 months for the tibia and 8 months for the radius. Patients could be actively rehabilitated all during the course of treatment and they achieved independent ambulation by the time the apparatus was removed. There were no complications.

Adolescent↗
PubMed1992

Heterogeneous Epstein-Barr virus infection patterns in peripheral T-cell lymphoma of angioimmunoblastic lymphadenopathy type.

In this study, 32 cases of T-cell lymphoma of angioimmunoblastic lymphadenopathy type (AILD-TCL) were investigated for their association with Epstein-Barr virus (EBV). For this purpose, three different approaches were applied: polymerase chain reaction (PCR) for the presence of EBV-DNA, in situ hybridization (ISH) for EBV-encoded small nuclear RNAs (EBER), and immunohistology for EBV-encoded latent membrane protein (LMP). PCR and EBER-ISH produced almost identical results, showing that all but one case of AILD-TCL contained EBV genomes. Three distinctive patterns of EBV infection were observed after immunophenotypical characterization of EBER-positive cells: (1) in 26% of the cases, B and T cells were infected, the majority of which were B cells of immunoblastic morphology located in the remnants of lymphoid follicles; (2) in 42% of the cases, the vast majority of infected cells were neoplastic T cells diffusely distributed in the lymph nodes, but infected B cells were also present; and (3) in 32% of the cases, there were only a few infected small lymphoid cells. Detectable LMP was frequent in cases exhibiting patterns 1 and 2. These findings suggest that in AILD-TCL patients, B cells and especially T cells are highly susceptible to a persistent EBV infection, which often leads to a growth advantage of the infected cells. Thus EBV, in conjunction with genetic abnormalities and selective defects of the immune system, might be involved in the pathogenesis of AILD-TCL.

Base Sequence↗
PubMed1992

Distribution and phenotype of Epstein-Barr virus-harboring cells in Hodgkin's disease.

Distribution and phenotype of Epstein-Barr virus (EBV)-harboring cells were determined in Hodgkin's disease (HD) biopsies by in situ hybridization with [35S]-labeled RNA probes specific for the small EBV-encoded nuclear RNAs, EBER1 and EBER2, in some instances preceded by immunohistology for CD20, CD30, CD45RO, and CD68 antigens, the T-cell receptor beta-chain, and latent membrane antigen (LMP) of EBV. Twenty-three of 46 HD cases displayed EBER transcripts in all Hodgkin and Reed-Sternberg (H-RS) cells, and 18 of these cases showed LMP expression exclusively in neoplastic cells. EBER+ small reactive cells were present in 39 cases in low numbers, and in three cases in abundance. Thus, presence of H-RS cells with or without LMP expression was not accompanied by an unrestricted proliferation of reactive EBER+/LMP- lymphoid cells in the majority of HD patients. Simultaneous in situ hybridization with [35S]-labeled immunoglobulin light chain (IgLC) gene probes and nonisotopically labeled EBER probe showed a phenotype of mature B lymphocytes and a polyclonal composition for a large proportion of the EBER+ small cells. However, in contrast to noninfected cells, CD20 expression was not detectable in many of these cells, which may indicate downregulation of certain differentiation antigens in latently EBV-infected small lymphoid cells in vivo.

Antigens, CD↗
PubMed1992

Response of refractory Hodgkin's disease to monoclonal anti-CD30 immunotoxin.

In Hodgkin's disease, Hodgkin and Reed-Sternberg cells consistently express the antigen CD30. We investigated the possible therapeutic role of an immunotoxin prepared by covalent linking of an anti-CD30 monoclonal antibody (Ber-H2) to saporin (SO6), a type-1 ribosome-inactivating protein. The immunotoxin (0.8 mg/kg in one or two doses) was given to four patients with advanced refractory Hodgkin's disease. In three, there was rapid and substantial reduction in tumour mass (50% to greater than 75%). Clinical responses were transient (6-10 weeks). In-vivo binding of the immunotoxin to tumour cells was shown by immunohistology in two patients. Antibodies to both parts of the immunotoxin developed in all patients.

Antibodies, Monoclonal↗
PubMed1992

Patterns of Epstein-Barr virus infection in non-neoplastic lymphoid tissue.

Taking advantage of the abundant expression of the small Epstein-Barr virus (EBV)-encoded RNAs (EBERs) in latently infected cells, we have analyzed 72 normal and hyperplastic lymph nodes and three tonsils of acute infectious mononucleosis (IM) for the presence and distribution of EBV+ cells using EBER-specific in situ hybridization, in some cases combined with immunohistologic demonstration of cell type-characteristic antigens. In IM, large numbers of EBV+ lymphoid B blasts were detectable in extrafollicular areas, whereas germinal centers were generally free of EBV+ cells. In reactive lymph nodes, the frequency of EBV+ cells varied with the degree of lymphoid hyperplasia and underlying immune status. The lowest numbers of EBV+ cells were detected in nonactivated lymph nodes and highest in human immunodeficiency virus-associated lymphadenopathy. If present in these lymph nodes, EBV+ cells were almost exclusively localized to extrafollicular areas, as also observed in IM. However, in contrast to IM, these cells were mainly small lymphocytes. Furthermore, in some instances, occasional scattered EBV+ cells were seen within germinal centers, and in two cases diffuse expansions of EBV+ cells occurred within a single germinal center each, indicating that under certain circumstances EBV+ B lymphocytes may participate in physiologic germinal center reactions. These findings reflect the interference of EBV with physiologic lymphoid differentiation pathways and provide a link to EBV-associated malignant lymphomas with a postulated origin from germinal center cells.

B-Lymphocytes↗