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An energy-saving facade panel for non-residential buildings has been numerically investigated. Structured like a composite Trombe-Michel wall, the panel consists of a glazing, an absorber plate and insulation and contains a dead air space between glazing and absorber, as well as a convection channel between absorber and insulation. The influence of convection channel spacing on both recovery of solar energy during sunshine periods and on heat losses during night hours has been assessed. Two different options have been considered. First, the total panel thickness was maintained, which involves an increase of channel spacing having to be compensated by a corresponding decrease of the insulation thickness. Then, this constraint was removed so that an increase in channel spacing was allowed to entail an equivalent increase of the total panel thickness. The results indicate that large spacing favors energy recovery during sunshine periods for both options and reduces, although only slightly, heat losses during night hours for the second option. In the case of the first option, however, these losses tend to grow when channel spacing increases.

Prostaglandin E2 (PGE2) is known to inhibit peripheral T-lymphocyte and thymocyte proliferation activated by antigens, mitogens or anti-CD3 antibodies. In this study, we have investigated, the effect of PGE2 on thymocyte proliferation induced by the combination of IL-4 plus PMA. PGE2 inhibits the proliferation of thymocytes activated by ConA, whatever the culture period; in contrast PGE2 shifts the kinetics of thymocyte proliferation after stimulation by IL-4 plus PMA, but does not sustain the proliferation beyond day 3. This effect depends upon cell density, IL-4 concentration and on the time that PGE2 is added to the culture. By use of the cAMP inducer, forskolin, or a cAMP analog, db-cAMP, we observed the same results, PGE2 increases the proliferation of CD8+ corticoresistant thymocytes (CRT) activated by IL-4 plus PMA, but inhibits that of CD4+ CRT. These results suggest that PGE2 can regulate thymocyte proliferation differently according to the activation pathway and the thymic subpopulations.

The specificity of anti-phospholipid auto-antibodies present in the serum of systemic lupus erythematosus patients towards the phospholipids has been studied by two different methods. The antibodies have been characterized either after affinity purification or by inhibition experiments. Our results clearly demonstrate that anti-phospholipid auto-antibodies recognize all phospholipids, whatever their polar head.

Recently, a new lymphokine called HILDA (human interleukin for DA cells) has been described and cloned. This cytokine, initially described to be produced by alloreactive T lymphocyte clones grown from a rejected human kidney allograft, is identical to other factors termed D-factor, differentiation-inducing factor, differentiation inhibitory activity, hepatocyte-stimulating factor III, and leukemia inhibitory factor. HILDA/LIF induces various effects on neural, hemopoietic, embryonic cells as well as on bone remodeling and acute phase protein synthesis in hepatocyte. In this study we demonstrate the presence of HILDA/LIF in the urine but not in the serum of kidney graft recipients during acute rejection episodes, whereas this lymphokine was detectable neither in the serum nor in the urine of kidney transplanted patients with stable renal function. These data reinforce the notion of a possible role for this lymphokine in the inflammatory and/or the immune response.

A method allowing the covalent binding of fatty acids to a carrier was developed. The absence of absorbed fatty acids was controlled by HPTLC. Rabbits were immunized with these immunogens. The antibodies obtained were studied by ELISA and were shown to be directed against the fatty acyl chain, whatever its length.

Screening 579 sera specimens obtained in Casablanca (Morocco) we have performed a retrospective seroepidemiological survey with regard to the prevalence of Chlamydia trachomatis involved in genital tract infections. The surveyed populations are divided into 3 groups: 177 patients affected with sexually transmitted diseases (STD), 319 reference patients, 83 maghrebian patients affected with STD but living in France. The study was performed by the indirect microimmunofluorescence technique. The prevalence of Chlamydia trachomatis ranging from 50% in the moroccan reference groupe to about 70% among patients with STD both in Morocco and Bordeaux indicates that Chlamydia trachomatis takes a significant part in STD observed in moroccan populations.

Aspirine-sensitive asthma (ASA) is a disease defined only by clinical criteria. It is an intrinsic asthma related to a hypersensitivity to aspirin. The illness is linked to abnormalities in platelet and macrophage arachidonic acid metabolism. We assessed in vitro the platelet chemoluminescence (CL) and lymphocyte proliferative response of ASA patients. We observed that platelets from patients and control do not generate any CL in the presence of aspirin. Concerning the proliferative response of lymphocytes, the in vitro effect of aspirin depends upon the origin of the lymphocytes tested. Thus aspirin clearly enhances the proliferative response of lymphocytes from normal subjects but diminishes the thymidine uptake by lymphocytes from ASA patients. This discrepancy in the in vitro response of lymphocytes from normal subjects and patients might be useful for in vitro diagnosis of ASA.

NK activity is regulated by arachidonic acid metabolites. More precisely PGE2 and LTB4 decreases and increases respectively non-MHC-restricted cytotoxicity in humans. We have observed similar data in mice since NK activity was inhibited by PGE2 (10(-6) to 10(-8) M) and enhanced by LTB4 (10(-8) to 10(-12) M). On the other hand when PGE2 and LTB4 were combined during the same assay the lysis percentage was smaller than the one which was induced by PGE2 alone. Because PGE2 increases intracellular cyclic AMP and that LTB4 augments cyclic GMP we used a cAMP inducer (forskolin) and a cGMP analogue (8 Br-cGMP) instead of eicosanoids and we observed similar data (i.e., a decrease of natural killing) as when PGE2 was combined with LTB4. When splenocytes are cultured for 1-4 days alone, cytotoxic activity decreases unless they are cultured in the presence of indomethacin. Cytotoxic activity of spleen cells cultured in the presence of PGE2 or LTB4 is respectively decreased or increased. However, splenocytes that were cultured alone for at least 24 hr were no longer sensitive to inhibition by PGE2 but were still PGE2-sensitive when cultured in the presence of LTB4.

Antibodies were labelled with indium-111 with a view to their use in the radio-immunodetection of cancers. The covalent coupling between indium-111 porphyrin and monoclonal antibodies (IgG and F(ab')2 fragment) was achieved using the ester activated method [N-hydroxy-succinimide/1-ethyl-3-(3-dimethylaminopropyl)carbodiimide]. After purification, this provided conjugated with specific activities of 6 muCi/micrograms Mab (9.3 molecules per Mab) or 1 muCi/microgram (F(ab')2 fragment (1.5 molecule per F(ab')2). ELISA procedures suggested the full retention of immunoreactivity by the radiolabelled antibodies.

Leucocytic Na+ K+ pump activity was assessed in 20 patients with advanced renal failure. Na+ K(+)-ATPase activity was reduced when compared with the values obtained from normal subjects (101.8 +/- 48.6 versus 165.13 +/- 8.9 microM of Pi hr-1.g-1; P less than 0.001) and the mean 86Rb uptake by U 937 cells was depressed by 38% after the addition of patients' sera. Subsequently, patients were put on a diet providing 0.3 g protein/kg body weight daily and supplemented with ketoacids. After three months of dietary treatment Na+ K(+)-ATPase activity increased to 142 +/- 48.3 (P less than 0.01) and reached normal values at the sixth month (162.8 +/- 54.70 microM of Pi hr-1.g-1; P less than 0.001) whereas 86Rb uptake increased by 23 percent when compared to initial values. These data suggest that among the different mechanisms which have been advanced to explain the defects in the Na+ pump observed in uremic patients, circulating inhibitors deriving from alimentary protein intake may affect cation transport.

The sera of systemic lupus erythematosus patients were tested by ELISA for the presence of autoantibodies against all the phospholipids: cardiolipin, phosphatidic acid, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol and phosphatidylserine. The quantity of phospholipid coated (in comparison with that initially deposited) on the microtitration plates was precisely evaluated in order to determine if the results (absorbance values) obtained for each phospholipid could be compared directly. The systemic lupus erythematosus sera tested gave positive results for all the phospholipids. The highest level of autoantibodies was observed with phosphatidic acid followed by phosphatidylserine, phosphatidylinositol, cardiolipin, phosphatidylglycerol, phosphatidylcholine and phosphatidylethanolamine. The sera seemed to contain antibodies directed either against all the 8 phospholipids tested or more specifically against one or two phospholipids. The results were compared with those obtained with 17 healthy sera. Much lower values were obtained for the sera of healthy subjects, the majority of which showed a weak binding, similar for all the phospholipids. These results suggest that the anti-phospholipid autoantibodies present in systemic lupus erythematosus sera are significantly higher than those of healthy subjects. It is concluded that in the investigation of anti-phospholipid antibodies, tests should be carried out for all the phospholipids.

Some aspects of immune response and coagulation disorders are investigated on rabbits infected by two strains of Trypanosoma (Trypanozoon) equiperdum giving diseases with different clinical expression. The study of antibodies to trypanosomes emphasizes the high immunogenicity of specific antigenic type glycoprotein, antigenicity of which seems to inhibit common antigens expression. Significant increase of anti-fibrinogen antibodies is discussed in relation with the presence of autoantibodies frequently discovered along trypanosomiasis. As IgM they contribute to the classical hypermacroglobulinemia of these diseases. Their casual contribution in the contribution in the casual contribution in the observed disorders is argued. The meaning of fibrinolytic system activation which is shown by FDP significant increase is equally argued: secondary fibrinolysis or Hageman Factor activation mediated by immune complexes.

We report two patients with chronic urticaria and serum monoclonal IgM without detectable lymphoid disease. In the 14 cases previously reported, clinical, histologic, and immunologic characteristics appeared very similar. The pathogenesis of this peculiar entity is discussed.

A 59-year-old woman with a history of papillary carcinoma of the thyroid gland developed three reddish nodules on the scalp. A skin biopsy showed a dermal tumor composed of sheets of clearly differentiated thyroid vesicles. Cutaneous metastases of thyroid carcinoma are very rare and this case is the first case confirmed by immunoperoxidase studies using monoclonal antithyroglobulin antibody. Positive reactions were obtained in colloid and at apices of thyrocytes. Monoclonal antibodies to human thyroglobulin may offer a unique opportunity to confirm the tissue origin of cutaneous metastasis.

Endocytosis of radioactive technetium colloïd by murine peritoneal macrophages cultures is measured after incubation. The results show a time and temperature dependant phenomen, reduced by hydrocortisone and inhibitor of glycolysis (NaF). Cytochalasine B and colchicine have no effect on the uptake of Technetium sulfur colloïd. These results suggest that the pinocytosis of technetium colloïd is independent of the actions of microfilaments and microtubules.

Peripheral lymphocyte subpopulations have been quantified by a direct and indirect, immunofluorescence technique, using monoclonal antibodies, in 22 patients with continued heavy drinking, hepatocellular dysfunction (spider angiomata, ascites, and factor V decrease) (group I), in 16 patients with a history of heavy drinking and abstinence maintained for at least 6 months and hepatocellular dysfunction (group II) and in 28 patients admitted for continued heavy drinking, without hepatocellular dysfunction (group III). Sixteen normal subjects were studied as controls. The total number of lymphocytes and T lymphocytes (OKT3+) were significantly reduced (p less than 0.001) in groups I and II. A significant decrease of B lymphocytes was observed in group II (p less than 0.02). The OKT8+ lymphocytes were significantly reduced in group I (p less than 0.01) and in group II (p less than 0.001); the decrease of the OKT4+ lymphocytes was significant in group II (p less than 0.01) only. The OKT4/OKT8 ratio was higher in group I (p less than 0.05) and group II (p less than 0.01) than in the control group. Normal values of total lymphocytes, B lymphocytes, T lymphocytes subsets and OKT4/OKT8 ratio were observed in group III. In group III, the lymphocyte subpopulations and OKT4/OKT8 ratio were similar in patients with or without abnormalities of liver function tests. In group I and II, no correlation was found between the lymphocyte subpopulations or the OKT4/OKT8 ratio and factor V or nutritional status assessed by anthropometrical and biological tests. T-cell imbalance in alcoholic liver disease does not seem to be related to alcohol consumption, factor V decrease or malnutrition.

Peripheral blood T lymphocytes and T cell subsets were explored in 25 patients with chronic urticaria and 25 healthy controls. Thirteen of the patients had lymphocytic or leukocytoclasic vasculitis. An abnormal distribution between helper and suppressor T cell subsets with decreased percentage of helper (OKT4) T cells was found as compared to controls.