Search PubMed⌕ Search

Biomedical subjects

P Smets

Publications and source records attributed to P Smets.

At least 55 records · Page 3Linked to original sources

Modulation of murine hemopoiesis by repeated injections of a glycoprotein extract from Klebsiella pneumoniae.

RU 41740, an immunomodulating agent extracted from the cell wall of Klebsiella pneumoniae, was tested for its ability to modulate hemopoiesis in mice treated intraperitoneally for ten days. In such conditions, a moderate anemia could be observed, which was rapidly reversible after the end of treatment. This anemia may partly result from a decrease of bone marrow erythroid colony forming units (CFU-E), this being incompletely compensated by the intrasplenic erythropoiesis. Moreover, the amount of granulocytes and their progenitors, i.e. granulocyte/macrophage colony forming cells (GM-CFC), increased both in the bone marrow and spleen. It is proposed that this effect of RU 41740 on granulopoiesis, which could explain the better resistance to infections in treated animals as observed elsewhere, is partly related to an increase of colony stimulating activity (CSA).

Adjuvants, Immunologic↗

Regulation of prostaglandin E2 and plasminogen activator by various immunomodulators in human monocytes.

Mononuclear phagocyte populations and monocytes are able to produce, among numerous substances, a neutral protease, i.e. plasminogen activator (PA) and prostaglandins. Since it has been shown that prostaglandins (PGs) and particularly PGE2 could exert an inhibitory effect on PA production by macrophages, we have measured the in vitro production of PA and PGE2 by monocytes isolated from healthy donors. These monocytes were cultured either in the absence or the presence of various immunomodulators: lipopolysaccharide from E. coli, concanavalin A and RU 41740 or Biostim a broad spectrum immunostimulating agent isolated from Klebsiella pneumoniae (Cassenne Laboratories, France). The production of PGE2 was proportional to the number of monocytes per incubation, and at a given cell concentration varied greatly from one subject to another. When considering PGE2 productions, the type of the response to the different immunomodulators varied from subject to subject and ranged from stimulation to no effect, or even inhibition. Moreover, a statistically significant, inverse relationship exists between the spontaneous production of PGE2 and the effect of each immunomodulator. For a given subject, all agents always acted in the same way and there was an inverse relationship between the effects of the immunomodulators on plasminogen activator and PGE2 production.

Adjuvants, Immunologic↗

Enhanced resistance of mice against influenza virus infection after local administration of glycoprotein extracts from Klebsiella pneumoniae.

RU. 41 740, a glycoprotein extract from Klebsiella pneumoniae O1K2 strain was tested for its ability to enhance resistance of mice against influenza virus infection. Local (aerosol) and systemic (IP) routes of RU. 41 740 administration were compared for their effectiveness in protecting mice. When RU. 41 740 was administered prophylactically (10 mg/kg) via aerosol route (5 consecutive days before challenge), significant protection (P less than 0.0001) was conferred against lethal aerosol inoculation of influenza virus. Treated mice exhibited a reduced mortality, a decreased lung-to-body weight ratio and lower intrapulmonary virus titers. The main glycoprotein soluble fraction (RU. 41 821) was as active as the total glycoprotein extract (P less than 0.0001). Whereas the local (aerosol) route of administration was effective, the systemic (intraperitoneal) route of administration did not confer significant protection against an aerosol inoculum of virus. This finding suggests the important role of local immunity. The levels of interferon in the lavage fluids of immunized and infected mice suggest that interferon is not the main protective mechanism. The enhanced protection observed could be related to an augmented humoral or cell-mediated response within the lung.

Adjuvants, Immunologic↗

High-dose alizapride versus high-dose domperidone: a double-blind comparative study in the management of cis-platinum-induced emesis.

A double-blind, randomized crossover trial was carried out in 44 cancer patients receiving chemotherapy with cis-platinum to compare the anti-emetic effectiveness and tolerance of alizapride and domperidone given in high dosage. Patients received 5 administrations of either 4 mg alizapride/kg body weight or 0.6 mg domperidone/kg during a chemotherapy session and then the alternative anti-emetic during the next session. Treatment order was randomized. Patients were followed-up for 12 hours and details recorded of the total time during which there was some nausea, the duration of mild and severe nausea, and the number of episodes of mild and severe vomiting. A note was also made of the duration of mild and moderate sedation, and the incidence and severity of any other side-effects either probably or possibly related to anti-emetic medication. The investigator gave an overall assessment of the severity of nausea and vomiting experienced during each chemotherapy session and an opinion on the comparative effectiveness of the two anti-emetics. At the end of the two sessions, patients were asked to state a preference, if any, for one or other treatment and to select which they would like to have for their next chemotherapy session. The results showed that whilst both alizapride and domperidone appeared to be equally effective in limiting mild nausea, alizapride was significantly better in preventing severe nausea and episodes of vomiting. In those cases where a positive choice between treatments was made, alizapride was considered to be significantly better than domperidone by the investigator and more patients preferred alizapride and would select it for their next session.(ABSTRACT TRUNCATED AT 250 WORDS)

Antiemetics↗

Opposite effects of a glucocorticoid and an immunostimulating agent on prostaglandin production by two different cell types.

Studies were performed to investigate the effects of several agents known to modulate wound healing on prostaglandin production by mouse embryo fibroblasts and adult thymic phagocytic cells in culture. Dexamethasone (10(-6)M) induced in both cell types a significant inhibition of the production of PGE2 and 6 keto PGF1 alpha, and a moderate inhibition of PGF2 alpha. Using an antiglucocorticoid compound, RU 38486, we were able to demonstrate that the inhibition of PG secretion represents a classical receptor-mediated effect of the steroid. In contrast, LPS and RU 41740 (5 micrograms/ml) induced a significant stimulation of PGE2 and 6-keto-PGF1 alpha secretion in the two types of cells. These results suggest that agents which modulate in different ways the process of tissue repair have opposite effects on PG production by cells involved in inflammatory and/or immunological reactions.

6-Ketoprostaglandin F1 alpha↗

Tiapride versus placebo: a double-blind comparative study in the management of Huntington's chorea.

A double-blind, placebo-controlled, crossover trial was carried out in 29 patients with Huntington's chorea to evaluate the effectiveness and tolerance of high doses of tiapride in the management of neurological symptoms. Patients were allocated at random into 3 groups to receive 3 g tiapride daily for two periods of 3 weeks either preceded, interrupted or followed by a 3-week period on placebo. Patients were assessed on entry and at the end of each treatment period using a battery of tests designed to measure choreatic movements, motor skills, recognition and reaction times, and mental state. Twenty-three patients completed the trial; only 2 of the 6 drop-outs withdrew because of drug-related side-effects (sedation and extrapyramidal signs). The results showed that tiapride treatment significantly improved choreatic movements and motor skills and these findings were supported by the objective psychometric measurements. Overall evaluation of effectiveness by the physician and patients indicated the significant superiority of tiapride over placebo. Treatment was generally well tolerated and although there were significantly more reports of sedation and extrapyramidal signs whilst patients were receiving tiapride, these effects were rated as mild in most cases and did not interfere with treatment.

Benzamides↗

[Activation of murine B lymphocytes by RU 41740, a glycoprotein extract from Klebsiella pneumoniae].

RU 41740, a glycoprotein extract from K. pneumoniae K2O1 strain, is an immune modulating compound which has been shown to reduce infectious episodes in deficient patients. Data from experimental designs suggest that RU 41740 could affect several target cells, such as T cells, B cells or macrophages. In the present report we show that RU 41740 is a selective B cell activator. It induces blast transformation in normal and nude mouse spleen cells and does not activate mouse T lymphocytes to proliferate. Activation of mouse spleen cells by RU 41740 is not affected by removal of adherent cells. RU 41740 also activates immunoglobulin secretion by murine B lymphocytes. Incubating spleen cells from C3H/HeJ mice with RU 41740 results in cell proliferation and activation of antibody forming cells. This suggests that B cell activation is not due to LPS contamination.

Animals↗

Diagnosis of pigeon breeder's disease by indirect immunofluorescence on sections of pigeon oviduct.

A new technique by indirect immunofluorescence on sections of pigeon oviduct, is described as an aid to diagnosis of pigeon breeder's disease. It is easy to do, inexpensive, and permits distinction between affected patients and exposed but unaffected persons. The main allergen, pigeon IgA, participates in the fluorescent responses of the mucous membrane and associated secretions. It has been possible to relate changes in antibody titre with improvement following treatment.

Alveolitis, Extrinsic Allergic↗

Tiapride versus glafenine: a double-blind comparative study in the management of acute rheumatic pain.

A double-blind study was carried out in 42 patients suffering from acute rheumatic pain to compare the analgesic effectiveness and tolerance of tiapride with that of glafenine, a widely used analgesic in Europe. Patients were allocated at random to receive either 100 mg tiapride or 200 mg glafenine 3-times daily over a period of 14 days. Pain intensity was rated daily by the patients using a visual analogue scale and an overall assessment of response to treatment was made by both patients and physician at the end of the study. The results showed that, whilst both treatments resulted in a marked reduction in mean pain scores, pain disappeared completely in 16 (76%) of the 21 patients treated with tiapride compared with 9 (43%) of the 21 receiving glafenine. There was also a significant difference in favour of tiapride in the physician's overall assessment of response which was considered as excellent in 71% of the patients on tiapride compared with 31% receiving glafenine. Both treatments were well tolerated and few side-effects were reported. Drowsiness occurred in 6 patients on tiapride but this was only mild in 5 and moderate in the other patient.

Adult↗

Experience of telecobalt therapy in operable breast cancer at J. Bordet Institute (1969-1975).

Between 1969 and 1975, postoperative radiotherapy was performed at the J. Bordet Institute on 787 stage I-III operable breast cancer patients. Crude 10 years survival rates are respectively 61% for stage I, 59% for stage II and 30% for stage III. The results have been analysed according to clinical characteristics of significant prognostic value and according to the technical conditions of treatment. The status of the axillary nodes appears to be the most important prognostic factor. Radiotherapy to the thoracic wall and lymph drainage areas has varied little throughout the whole period with the dose to the internal mammary chain being the only parameter which varied significantly. Loco-regional recurrences occurred only in 5, 2% of patients without distant metastases appearing previously or during the following year (2.4 for stage I patients). Severe sequelae were seen in only a very few cases. Survival appears significantly correlated with an adequate dose of irradiation to mammary node chain.

Breast Neoplasms↗

Effects of obstructive sleep apneas on transcutaneous oxygen pressure in control infants, siblings of sudden infant death syndrome victims, and near miss infants: comparison with the effects of central sleep apneas.

In order to investigate the effects of obstructive sleep apneas upon transcutaneous PO2 75 polysomnograms, recorded during night sessions in 25 control infants, 25 siblings, and 25 near miss for sudden infant death syndrome (SIDS) infants were studied. These observations were compared with the decreases in transcutaneous PO2 measured during central sleep apneas in the same infants. During a total of 707.6 hours of sleep, 33 obstructive apneas and 1,650 central apneas were recorded. Obstructive apneas were seen in three control infants (three episodes), one sibling (five episodes), and six near miss for SIDS infants (25 episodes). The obstructive apneas tended to be short (less than 10 seconds). Comparatively, the central apneas were equally distributed in the three groups of infants, and only the near miss children presented apneas that lasted as long as 19 seconds. The decrease in transcutaneous PO2 was proportional to the duration of both types of apnea, but for a given duration the decrease in transcutaneous PO2 was significantly greater for the obstructive apneas than for the central apneas (with a mean difference of 7.59 +/- 0.53% PO2. It is concluded that the hypoxic effects of the obstructive apneas might have important clinical implications in infants, such as the near miss for SIDS.

Female↗