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Biomedical subjects

E Klein

Publications and source records attributed to E Klein.

At least 523 records · Page 29Linked to original sources
PubMed1978

Sorbent-filled hollow fibers for hemopurification.

Filled hollow fibers were prepared and evaluated for application in hemosorption. Powdered activated carbon, urease-carbon, and macroporous ion exchange resins were used as fillers in highly permeable cellulose acetate hollow fibers. The carbon-filled hollow fibers had better mass transfer properties than encapsulated carbon in solid form. Zirconium phosphate and 2 synthetic zeolites were tested for ammonium ion adsorption from buffered saline and Ringer's salt solutions. Synthetic zeolites were found to have higher specificity and capacity for ammonium ion adsorption than zirconium phosphate. Projections are that hemosorption devices utilizing urease, carbon, and zeolites could remove all nitrogenous waste metabolites currently being treated only by dialysis. Oxystarch and oxystarch derivatives were tested for direct urea adsorption and were found unsuitable for this application.

Adsorption↗
PubMed1977

Human tumour--lymphocyte interaction in vitro. V. Comparison of the reactivity of tumour-infiltrating, blood and lymph-node lymphocytes with autologous tumour cells.

Lymphocytes prepared from the blood, tumour-draining lymph node and tumour were tested for immune reactivity with freshly isolated autologous tumour cells from biopsies. Reactivity was assessed by the autologous tumour stimulation assay and by lymphocytotoxicity. Activity was found in 6/11 blood preparations, 7/10 lymph nodes and 1/7 tumour-infiltrating lymphocytes in tumour stimulation assays and in 6/19 blood, 8/18 lymph-node and 5/20 tumour-infiltrating lymphocytes in cytotoxicity assays. Tests with material from patients with nasopharyngeal carcinoma showed a higher frequency of cytotoxicity in the tumour-infiltrating lymphocytes than in other solid tumours. There was a correlation between results of the two assays when performed on the same preparations and between the levels of reactivity in lymph node and blood from the same patient. Cytotoxicity in the lymph nodes showed specificity in that cells from a long-term culture (K562) known to be sensitive to natural killer activity and from allogeneic tumour biopsies were only rarely damaged. Cytotoxicity against K562 was more frequently determined in blood lymphocytes. Tumour-infiltrating lymphocytes were non-reactive in patients when the blood and lymph-node lymphocytes were active.

Cytotoxicity, Immunologic↗
PubMed1977

Immunization of mice with syngeneic Moloney lymphoma cells induces separate antibodies against virion envelope glycoprotein and virus-induced cell surface antigens.

Immunization of mice with heavily irradiated syngeneic Moloney lymphoma cells evokes antibodies against the major viral envelope antigen, gp71, and the Moloney virus-induced cell surface antigen (MCSA). A9HT cells, an L-cell subline, react with the antibodies against the viral envelope antigen only; this reaction can be completely inhibited by virus or purified gp71. Reactivity to Moloney lymphoma cells (YAC) was only partially inhibited (maximum 30%) or not at all. This can be attributed to the reaction of the YAC cells with antibodies directed against MCSA, a nonvirion cell surface component according to both biological and biochemical evidence. Antibody-induced capping of gp71 or p15(E) did not change the membrane distribution of MCSA or H-2, indicating that these antigens represent distinct entities on the cell surface. MCSA showed only minimal capping and thereby differed in behavior from both H-2 and virion antigens. gp71 could be capped by the mouse antiserum as revealed by subsequent staining with monospecific anti-gp71 antiserum. Under ordinary test conditions this reactivity is overshadowed by the reaction against MCSA. The lack of MCSA capping reflects a difference in anchorage of this antigen.

Antibodies, Viral↗
PubMed1977

Lymphocyte cytotoxicity against autologous tumour biopsy cells in humans.

By the application of separation techniques in a stepwise manner to mechanically prepared cell suspensions from human tumour biopsies it has been possible to isolate tumour cells having high viability and low contamination with host cells. These tumour cells have been used as targets in 51Cr release cytotoxicity assays using autologous lymphocytes from blood or lymph node as effectors. It has been possible to investigate this reactivity in 30 patients with malignant and four patients with benign tumours. Significant autologous cytotoxicity in the blood lymphocytes was detectable in two of 12 lung tumours, nine of 18 other carcinomas and sarcomas but in none of the benign cases. Cytotoxicity was not limited by the presence of obvious residual disease at the time of operation although reactivity was less frequently detectable in patients with secondary involvement. Reactivity in the tumour-draining lymph nodes largely paralleled that in the blood in the limited number of patients examined. The technical problems encountered during this study and the role of natural cytotoxicity in the interpretation of these data are discussed.

Animals↗
PubMed1977

Characterization of human lymphocyte subpopulations for cytotoxicity against tumor-derived monolayer cultures.

Lymphocyte fractions of three healthy donors were tested for cytotoxicity in a 48-h assay on several tumor-derived lines. Analysis of surface markers indicated that a non-T non-B fraction comprising about 50% Fc-receptor-positive cells was most potent. The cell yield in this fraction was on the average 6.5% of the non-fractionated population. Elimination of Slg positive cells did not influence the cytotoxic potential. Pure T cells isolated with E-rosetting subsequent to passage on nylon wool column had no or very low low cytotoxicity. We had indications that cells without conventional markers--"null" cells--were also cytotoxic.

Cell Line↗
PubMed1977

Natural cytotoxicity in man: activity of lymph node and tumor-infiltrating lymphocytes.

Lymphocytes from blood, lymph node and tumor have been tested for cytotoxicity against the K562 cell line which is known to be highly sensitive to lysis by spontaneously reactive cells. Cytotoxicity was found in all 13 samples from healthy donors and in 17/32 cancer patients. By contrast, activity was determined in only 1/18 lymph node and 1/14 preparations of tumor-infiltrating lymphocytes. Lymph node cells were similarly nonreactive against 3 other cell lines known to be sensitive to natural cytotoxicity. Studies of the composition of the effector populations revealed no absolute deficit of a particular cell type although there were differences between them resulting from the different isolation procedures used. Enrichment of the lymph node population for non-T, non-B lymphocyte was ineffective in inducing cytotoxicity in previously nonreactive samples although this procedure uniformly increased the cytotoxic potential of blood lymphocytes. Tests with blood taken during operation showed that the lack of reactivity in these preparations was unlikely to be a result of the effects of anesthesia or surgery. The reason for the low cytotoxicity in the lymph node and tumor-infiltrating lymphocytes is as yet undefined.

Anesthesia↗
PubMed1977

Establishment in continuous culture of a new type of lymphocyte from a "Burkitt like" malignant lymphoma (line D.G.-75).

The isolation and establishment in vitro of a hitherto undescribed type of lymphocyte designated D.G.-75 is reported. The original inoculum was derived from the pleural effusion of a child with a primary abdominal lymphoma, which clinically and histologically resembled Burkitt's lymphoma. In addition to the absence of the EBV genome and EBV receptors, this line possesses a number of other properties which distinguish it from previously described lymphoblastoid cell lines. It has different growth characteristics and morphology; does not form EAC or E rosettes (representative of B and T) cell surface markers, respectively); possesses IgM-kappa immunoglobulins on the cell surface (B lymphocyte), has an unusually high cap-forming ability and low agglutinability with fluorescent concanavalin A. One homologue of the No.14 chromosome pair possesses extra chromatin material as revealed on chromosome banding. This abnormal chromosome marker is similar to that described in biopsies and cultured tumor cells from patients with African Burkitt's lymphoma.

Agglutination Tests↗
PubMed1977

Pulmonary function in nonsmoking subjects with alpha1 antitrypsin deficiency (MZ phenotype).

We measured pulmonary functions in 10 nonsmoking asymptomatic subjects, ages 40.5 years +/- 9.2 years, with alpha1 antitrypsin heterozygous deficiency (phenotype MZ). The subjects were longstanding residents of the greater Los Angeles area. The range of physiologic studies and per cent of normal predicted values were forced vital capacity (FVC), 2.8 to 7.0 liters (86 to 124 per cent predicted); ratio of the forced expiratory volume in 1 second to the FVC, 70 to 86 per cent (86 to 104 per cent predicted); the ratio of the residual volume to total lung capacity, 28 to 44 per cent (94 to 119 per cent predicted); total lung capacity, 4.8 to 9.8 liters (80 to 119 per cent predicted); flow at 50 per cent FVC, 3.1 to 7.8 liters per second (69 to 140 per cent); and volume of isoflow, 7.3 to 26 per cent of forced vital capacity (38 to 137 per cent predicted). In eight patients studied, static deflation pressure volume curves were normal, and at respiratory rate of 60 breaths/min the ratio of dynamic compliance to static compliance did not fall below 84 per cent. We have found that these nonsmoking heterozygotes with alpha1 antitrypsin deficiency have normal pulmonary functions (within 1.67 SD of predicted mean).

Adult↗
PubMed1977

Immune surveillance against virus-induced tumors and nonrejectability of spontaneous tumors: contrasting consequences of host versus tumor evolution.

Spontaneous tumours are defined as tumors that develop in the absence of all experimental interference. In contrast to the widely documented, strong rejection reactions against most virus-induced tumors, spontaneous tumors evoke little or no detectable rejection reaction in intact or preimmunized syngeneic hosts. The difference can be viewed in relation to the contrasting natural history of the two conditions. Spontaneous tumors evolve in several steps, as a fule. "Tumor progression" is a microevolutionary process at the level of the somatic tissue where successive clonal variants replace each other. Each new variant gains the upper hand due to its greater independence of some restricting host mechanism. Independence of immune restrictions must be part of this process. Host selection for immune resistance apparently plays no major role here, presumably because most of the naturally occurring tumors arise after the host has passed the peak of its reproductive period. Protection against the oncogenic effects of ubiquitous tumor viruses is, on the other hand, the result of host selection for immune mechanisms favoring prompt rejection of virus-transformed cells. This is neither synonymous with nor related to protection against the viral infection per se, which is frequently successful and usually quite harmless. A certain relationship can be perceived between the degree of viral ubiquity and the strength of immune protection against the corresponding tumor cells. Natural selection for host recognition of commonly occurring, virally induced changes in neoplastic cell membranes can be surmised to occur, at least in part, by the fixation of appropriate immune responsiveness (Ir) genes. The role of Ir genes for tumor recognition can be approached by the genetic analysis of the F1 hybrid resistance effect. Unresponsiveness to spontaneous tumors may be overcome by target-cell modification, e.g., by chemical coupling, somatic cell hybridization, or viral "xenogenization".

Animals↗
PubMed1977

Ventilatory response and drive in acute and chronic obstructive pulmonary disease.

We measured hypercapnic ventilatory responses using the rebreathing technique and ventilatory drive using mouth occlusion pressure in 15 normal subjects (6 with added external inspiratory resistance), 11 asthmatics, and 17 patients with chronic obstructive pulmonary disease (9 with chronic CO2 retention and 8 with normal values for arterial pco2). normal subjects, obstructed normal subjects, asthmatics, and patients with chronic obstructive pulmonary disease without CO2 retention had overlapping ventilatory responses. Ventilatory drive was increased in asthmatics and obstructed normal subject. Patients with chronic obstructive pulmonary disease without CO2 retention maintained a ventilatory drive similar to that of normal subjects, whereas patients with chronic obstructive pulmonary disease with chronic CO2 retention demonstrated blunted ventilatory drives as a group, even though 5 of 9 had normal drives. Patients with CO2 retention also had the greatest obstruction when compared to other groups. In some patients, chronic CO2 retention is primarily a consequence of mechanical end-organ limitation rather than a blunted neurorespiratory center output. Acute airway obstruction is associated with an increased drive, which may become reduced with chronic obstruction.

Acute Disease↗