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S Cornain

Publications and source records attributed to S Cornain.

11 recordsLinked to original sources
PubMed1995

Reduced endothelial cell migratory signal production by endometrial explants from women using Norplant contraception.

Bleeding problems can be one of the major reasons for women to discontinue the use of hormonal contraceptives. Causes of endometrial bleeding can include disturbances in endometrial regeneration and angiogenesis. Endothelial cells migrate and proliferate rapidly as part of the angiogenic process under the influence of appropriate stimuli. The aim of this study is to investigate the production of endothelial cell migratory signals by endometrial explants from women receiving Norplant and to compare it to that of those with a normal menstrual cycle. The subjects were selected from Norplant users with an exposure of 3-9 months. The endothelial cell migratory signal production was assayed using the Folkman method (1989), modified by Rogers (1992). Blood serum concentrations of oestradiol, progesterone and sex hormone binding globulin were monitored for 2 weeks prior to endometrial biopsy. Endothelial cell migration toward endometrial explants of 30 women as control and 46 Norplant acceptors was assayed. The results showed that endothelial cell migratory activity toward endometrial explants from the control group was significantly higher than toward those from Norplant acceptors (z = 3.89, P < 0.001). There were no differences between endometrial endothelial cell migratory activities in Norplant acceptors with bleeding or without bleeding problems.

Adolescent↗
PubMed1987

Immunological changes and recovery in patients with dengue haemorrhagic fever.

In studying the immunological changes in dengue haemorrhagic fever, three phases of investigations had been carried out. During the earlier phase of investigation, significant immunological findings were obtained, namely the elevation of immunoglobulins, activation of complements, formation of circulating-immune-complexes and diminished number of T lymphocytes. The changes tended to recover during the convalescent phase. During the second phase of investigation, the extended studies revealed further confirmation of T cell impairment during the acute phase which tended to recover during the convalescent phase. Elevated number of Fc-receptor- and C3-receptor-bearing cells was also observed in some patients, variedly occurred during the acute or the convalescent phase. Elevated number of B cells was only found in small proportion. Significantly high number of activated RNA-rich lymphocytes was found in almost the half of patients. The virus-lymphocyte interaction has been demonstrated by the detection of viral antigen on the surface of lymphocytes in a proportion of patients. The circulating-immune-complexes was shown to contain viral (DEN-1) antigen. During the third phase of investigation, the impairment of T cells was further analyzed on their regulatory T populations. Impairment of total T lymphocytes, helper-T and suppressor-T was detected during the acute phase and tended to recover during the convalescent phase. The reversed changes occurred on B cells, The immunological changes and recovery are considered to be related to the stimulatory and suppressive effects of the dengue virus and regulatory mechanism.

Antibody Formation↗
PubMed1978

Characteristics and in vitro growth influencing effects of the spleen cell population in a methylcholanthrene induced mouse sarcoma system.

Effects of immunization on the growth of the early passages of two methylcholanthrene induced mouse tumors, MC57 X and MC57 Y, were different. For tumor X, immunization resulted in complete protection, while tumor Y was enhanced. The enhancing effect was individual tumor specific. The spleens of tumor bearing animals were enlarged and the proportion of blasts, EAC- and EA-rosettes were increased. This was the case for the T cell enriched population also. In lesser extent, such findings were also obtained in the lymph nodes. The spleens of control and tumor bearer animals were tested for effect on the in vitro growth of tumor cells. From both sources non-adherent subpopulations enriched in C3 receptor bearing cells substantially reduced the number of tumor cells. Using the T cell fractions, only those derived from tumor bearer spleens were active. The in vitro effects on the growth of the two tumors were cross-reactive. T cells exhibiting growth inhibition in vitro were detectable 13 days after subcutaneous inoculation, when the tumor was already measurable, while earlier the T cells enhanced the growth. The outcome of the in vitro tests reflected only the tumorous status of the animal and did not relate to preimmunization.

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

Sensitization of rat T cells to syngeneic tumor cultures by cocultivation in diffusion chambers.

Total population and T cell enriched fractions of rat spleen were cultivated in diffusion chambers implanted intraperitoneally to mice and rats. 10-16% of the input cells were recovered after 5 days. When the chambers were carried in the xenogeneic environment activation occurred as indicated by blastogenesis and non-discriminative cytotoxicity. Specific activation of the T population was induced by mixed lymphocyte-tumor culture in chambers implanted in rats. The presence of tumor cells induced blastogenesis, elevation of the proportion of Fc receptor positive cells and generated cytotoxic cells to the sensitizer tumor. The precursor of cytotoxic cells did not have Fc or C3 receptors since nylon wool colum passed fractions depleted from these cells by elimination of EA- or EAC-rosettes were also activated.

Animals↗
PubMed1977

Fc receptors on human blood B lymphocytes.

The frequency of Fc-receptor positive B lymphocytes in human blood was investigated. Under the conditions used heat-aggregated gammaglobulin binding and EA(ox)-rosette formation labelled the same lymphocyte populations. Using various techniques, double marking and cell separations the proportion of Fc-receptor positive cells within the surface Ig carrying population was estimated to be between 11-8 and 36-2%. The proportion of SIg carrying cells within the population forming EA-rosettes was between 11 and 26-4%. This represents extreme values due to known technical circumstances.

B-Lymphocytes↗
PubMed1976

Search for anti-tumor response in a bone tumor patient with a long clinical history.

Immunological studies are presented on a patient with a long clinical history suggesting the existence of a tumor-specific immune response. His tumor, first considered benign, progressed to a highly malignant osteosarcoma. Cell-mediated immune reactivity against biopsy cells and against tumor extract was detected in vitro by the autologous tumor stimulation test (ATS) and in vivo by the skin test. In one ATS-test with tumor extract, blastogenesis of T-cells was demonstrated. The amount of Ig(s) in consecutive biopsies increased. Biopsies taken in the later period of the disease stimulated only after trypsin treatment. This stimulation was inhibited by autologous serum or acid eluate of the biopsy. The inhibitory factor in the serum was not intact immunoglobin. Blood lymphocytes did not show a discriminatory or disease-related cytotoxicity, either directly or after co-cultivation with the tumor material. Lymphocytes isolated from one biopsy were non-reactive in both the ATS and the cytotoxicity test.

BCG Vaccine↗
PubMed1975

Antibodies and antigen expression in human melanoma detected by the immune adherence test.

By means of a modified immune adherence (IA) technique, sera from melanoma patients were tested for the presence of antimelanoma antibodies. In total 13/73 sera tested showed a positive IA reaction of which 4/6 sera showed a positive reaction in the autologous situation. Sera from 33 patients with other tumors, 7 patients with non-neoplastic diseases and 50 healthy individuals did not show any IA reactivity towards melanoma cells. The reaction seemed to be selectively directed against tumor-associated antigens (TAA) on melanoma cells. No correlation with the stage of the disease could be found. Longitudinal studies indicated that conversions in antibody activity did not correlate with the clinical state of the patients. There was also no correlation with the corresponding in vitro data obtained in cell-mediated immunity tests. Cell lines and short-term cultures originating from tumors from different melanoma patients shared a common antigenicity. The expression of TAA on cells from a melanoma cell line fluctuated significantly during prolonged culture. The expression of TAA was influenced by the culture conditions and the growth state of the cells. A relation between TAA-expression and cell cycle phase was demonstrated.

Antibodies, Neoplasm↗
PubMed1975

Spleen-cell reactivity against transplanted neurogenic rat tumors induced by ethylnitrosourea: uncovering of tumor specificity after removal of complement-receptor-bearing lymphocytes.

Spleen cells from BDIX-rats bearing either GVlAl-tumor (a syngeneic mixed glioma) or NVlAc-tumor (a cloned syngeneic neurinoma of the peripheral nervous system) were cytotoxic to both tumor cells in vitro. However, the tumors displayed individually distinct antigenic specificities by in vivo rejection tests. Their in vitro cross-reactivity disappeared when a particular subpopulation of the spleen cells was used. The procedure of lymphocyte purification included three consecutive steps: treatment with carbonyl iron and magnetism, passage through a nylon wool column, and finally removal of complement receptor-bearing cells present in the colum-excluded population. Cross-reactivity between the syngeneic tumors persisted after the first two steps of lymphocyte purification. In contrast, specific cytotoxic reactions were observed against each individual tumor subsequent to the removal of the remaining C3 receptor-positive but surface Ig-negative cells. While killer cells were present in normal spleen-cell populations, these were almost completely eliminated by passage through the nylon wool column.

Animals↗