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Biomedical subjects

J Dufer

Publications and source records attributed to J Dufer.

At least 55 records · Page 3Linked to original sources
PubMed1983

Cytochemical analysis of human peripheral blood lymphocyte subsets defined by monoclonal antibodies.

Human blood lymphocyte subpopulations, revealed by a panel of commercially available monoclonal antibodies by means of a rosetting technique, were submitted to direct cytochemical analysis and were shown to have distinguishing characteristics. T cells reactive with OKT3 antibody (T3+) displayed higher beta-glucuronidase and dot-like alpha-naphthyl acetate acid esterase (ANAE) activity than T3- cells. Helper/inducer cells (T4+) were characterized by a high level of dot-like ANAE activity, whereas cytotoxic/suppressor cells (T8+) displayed selective naphthol-ASD-chloroacetate esterase activity. These results provide evidence for association of some cytoplasmic enzyme activities with the expression of membrane differentiation markers defined by monoclonal antibodies.

Acid Phosphatase↗
PubMed1980

[DNA synthesis and antibody formation in spleen cells of the mouse after in vivo immunization by Escherichia coli lipopolysaccharide modified by polymyxin B].

The addition of polymyxin B to Escherichia coli lipopolysaccharide alters some properties of this molecule, when injected to the Mouse. Spleen cells DNA synthesis was inhibited and delayed when the other functions tested: specific antibody synthesis ad immunoglobulin synthesis were unchanged. The possible implications of this dissociation are discussed.

Animals↗
PubMed1980

Nonspecific acid esterase activity in human autologous rosette-forming lymphocytes.

Alpha-naphthyl acetate esterase (ANAE) distribution was studied in human peripheral blood total T cells (E-RFC) and in T lymphocyte subpopulation: Autologous rosette-forming cells (A-RFC) obtained in different conditions. The percentage of ANAE localized forms is always lower in A-RFC than in E-RFC, showing an immature state of these autoreactive cells. Among the A-RFC, the percentage of localized forms is correlated with the avidity of cells for autologous erythrocytes, suggesting linkage between A-RFC immaturity and avidity.

Adult↗
PubMed1978

Cytochemical and ultrastructural characters of human peripheral blood lymphocytes according to their surface markers.

The human peripheral blood lymphocytes are characterized by different surface markers: The B lymphocytes by the EAC rosettes and surface immunoglobulin and the T lymphocytes by the E-rosettes. Each lymphoid population has been studied for cytochemical parameters (Acid phosphatase, beta-glucuronidase) by light microscopy and for ultrastructural characteristics by micromanipulation and immunoelectronmicroscopy. It has been shown that the studied enzymes are markers for T cells with high affinity for sheep red blood cells and that the separation of lymphocytes by the rosette techniques leads to homogenous cell populations at the ultrastructural level. A classification of peripheral lymphocytes according to their immunocytochemical profile is discussed.

Acid Phosphatase↗
PubMed1977

[Cytochemical study of leucocytes of DBA/2 Mice after leukemia L1210 tumor graft].

The growth of L 1210 leukemia in DBA/2 strain mouse, provokes in the grafted animals intraleucocytic enzymatic modifications. As increase of acid phosphatase and a decrease of beta-glucuronidase were observed in the lymphocytes, the level of polymorphonuclear non-specific esterase being decreased. The implications of these modifications in the host response toward the tumor is discussed.

Acid Phosphatase↗
PubMed1977

[Technics for the study of a total leukocyte dialysate and its fractions].

The crude dialysate extracted from human white blood cells from a thousand unselected donors were studied by leukocyte migration inhibition test with measles antigen. This dialysate and its fractions eluted from Biogel P4 and P6 chromatography were compared towards rosette restoration test and nucleotide composition.

Cell Migration Inhibition↗
PubMedDate not supplied

Contribution of quantitative cytology to the cytological diagnosis of thyroid neoplasms.

In a previous study we determined that the fine needle aspiration (FNA) biopsy of thyroid produces 16% of false-negative cases (FNC). In order to determine the value of quantitative cytology (QC) as a tool for predicting the FNC result, thirty-seven cases, 18 of which were operated (histologically benign: 13; malignant: 3; atypical adenoma; 2) were examined for quantitative morphologic characteristics. The smears were stained by the Feulgen method and nuclear parameters of morphometry, densitometry and texture were computed by a cell image processor. The system was first taught to recognize the benign and malignant cells from 3 histologically benign and malignant lesions. Thereafter, prospective cases were submitted to decisional analysis. For 10 histologically benign cases, the benign cell rate (bcr) ranged from 65% to 99.4 (95% confidence interval). Among the patients with a cytologically benign lesion (and an unknown histological diagnosis), 2 had a bcr less than 65% and so were not to be regarded as benign. The follow-up of these patients will show whether they represent FNC and whether QC can be of predictive value in assessing the FNC.

Adolescent↗
PubMedDate not supplied

Phagocytosis of the streptococcal preparation OK-432 (picibanil) by non-phagocytic human leukemia K 562 cells and its modulation by tumor cell differentiation.

OK-432, an inactivated and lyophilized preparation of a low-virulence strain of Streptococcus pyogenes induced a phagocytosis process in human erythroleukemic K 562 cells. This process seems to be specific to the cell line, known however as non-phagocytic, and specific to the bacterial preparation. Transmission and scanning electron microscopy confirmed phagocytosis. Increased lysosomal activity was also demonstrated by cytochemical and biochemical criteria. The induction of phagocytosis required an intact cell surface membrane and sialo-glycoproteins seemed to be implied. The phagocytosis was inversely correlated with the erythroid differentiation of the K 562 cell. Hemin-treated K 562 cells and the markedly erythroid K 562 clone showed a decreased level of phagocytosis. The phagocytosis level in a K 562 clone expressing Fc (IgG) receptors was not altered by OK-432. In addition, a weak erythroid K 562 clone expresses the same level of phagocytosis as the total population.

Acid Phosphatase↗