PubMed Health⌕ Search

Biomedical subjects

D Mathieu

Publications and source records attributed to D Mathieu.

At least 235 records · Page 13Linked to original sources

[Cellular effects of anesthetics].

Anesthetic drugs have multiple effects on cellular structures and functions. Among these are membrane perturbations, cell division, DNA synthesis, disruption of microtubules and microfilaments, phagocytosis and cell locomotion. Some of these effects are reversible, and directly correlated to concentration and length of exposure; other, however, seriously compromise cellular integrity and vital functions. A review of the literature and current work are presented.

Anesthetics↗

Immunological studies in human ageing. I. In vitro functions of T cells and polymorphs.

T-cells were investigated by the E rosette assay, PHA stimulation, allogeneic MLC and CML responses, in a group of 100 healthy aged people over 70 years old, and compared to young control individuals less than 45 years old. No major difference was found between the two groups, except for PHA stimulation which was significantly reduced in old individuals when low mitogen concentration was used. These observations suggest that only some T cells subsets are affected by ageing, without modification of the total T lymphocyte number. Contrarily, the phagocytic activities of polymorphonuclear cells assessed in a group of 38 aged people were dramatically decreased, using either the NBT test or a direct phagocytosis assay.

Aged↗

Induction of delta 3(4) ketosteroid synthesis by interferon in mouse adrenal tumour cell cultures.

Interferon, like cholera toxin, induces in mouse adrenal YI cells the production of delta 3(4) ketosteroids. In parallel, cyclic AMP (cAMP) is activated. At high concentrations, mouse but not human interferon induces a cell rounding effect, similar to that obtained with cholera toxin. In YI cells transformed by simian adenovirus 7, production of cAMP is still increased by that of steroids is blocked. The role if interferon in these cellular events is discussed.

Adenoviridae↗

Acute intoxication with diisopyramide: clinical and experimental study by hemoperfusion an Amberlite XAD 4 resin.

Diisopyramide overdose induces an early and severe cardiogenic shock; hemoperfusion on resin (Amberlite XAD 4) is the most efficient treatment. In vitro, 92% of the drug is adsorbed in 240 min. In dog, the plasmatic epuration is 66% with a mean plasma clearance of 74% plasmatic flow. A woman who had absorbed 4.50 g diisopyramide showed an idioventricular rhythm. The cardiac electrical stimulation and positive inotrope drugs were inefficient. Hemoperfusion on resin Amberlite XAD 4 corrected hemodynamic and ECG disturbances in 4 h. The epuration was proved by the decrease of diisopyramide plasma level: 24.4 micrograms/mL before epuration, 1.9 micrograms/mL after epuration, and a mean plasma clearance of 107.8 mL/min (61% of the plasmatic flow). Hemoperfusion of resin (Amberlite XAD 4) is more efficient than hemodialysis (cuprophan) and hemofiltration (polyacrylonitrile). The system that we have used is well tolerated and of low cost.

Animals↗

[Production of O antigens and antibodies during urinary tract infections due to Escherichia coli (author's transl)].

In 138 adults with monomicrobial E. coli urinary tract infections, IgG coated bacteriuria (ACB) are found in 9/10 acute pyelonephritis, 21/24 chronic pyelonephritis, 2/5 acute prostatitis, and in only 6/99 lower UTI. These urinary antibodies are synthetised localy because IgA-S are found in 75%, in the kidney because humoral IgG antibodies are detected in only 40% of the ACB + patients. O6, O18, O22, O75, are the four most frequent O antigens (47,5%) and no difference were found in the distribution of O serotypes according to ACB production or clinical signs. But rough strains are significantly more frequent in pyelonephritis, suggesting a modification of the bacterial wall. The use of ACB test and O serotyping allows a better follow-up of patients, but relapses with ACB- and reinfection with ACB+ show the complexity of the relation host-E. coli.

Acute Disease↗

[Loss of steroidogenesis in a mouse adrenal cell line after simian adenovirus 7 (SA7) transformation].

After transformation by the simian adenovirus 7 (SA7), the Y-1 Mouse adrenal tumor cells are no longer able to produce steroïds either spontaneously, or after specific stimulation. Nevertheless, these stimulations are able to increase the level of cAMP both in transformed and original cell line. The differentiation is associated with an intracellular modification of steroïdogenesis which seems to be localized in the metabolic chain of steroïd synthesis after the increase of the cAMP level.

Adenoviridae↗

[Variations in the phagocytic potency of circulating leukocytes from rats which received a thermal injury. Effects of an immunostimulation with Corynebacterium granulosum (author's transl)].

Experiments were carried out to study in vitro the variations of phagocytic activity of circulating leukocytes from rats which received a thermal injury and were either immunostimulated or not by a single iv injection of C. granulosum. The thermal injury which was applied at about 10 percent of the body surface was of an intermediary type ; it developed towards necrosis before cicatrising on about the 30th day. Phagocytic activity was expressed as the percentage of "active" phagocytes or of those cells which phagocytosed Sta. aureus and S. typhi murium. In not immunostimulated rats, the phagocytic activity was profoundly depressed as a result of the thermal injury ; this was most marked at about 8 days after the thermal injury (close to 38% compared with 80% in control-not-burned-rats). The phagocytic potency or circulating leukocytes from burned and immunostimulated rats corresponded at about the 8th day to that of healthy rats. The reported variations are statistically significant, as assessed by the Student "t" and X2 tests. Our study showed that those rats which were burned in our experimental conditions responded favourably to the immunostimulation. It would be interesting to check whether the use of anaerobic corynebacteria in man could represent an adjunct treatment of those septic complications which are so frequent in severe burns.

Animals↗

Detecting enteropathogenic strains of Escherichia coli of porcine origin. 2. Relationship between O and K antigens and the production of enterotoxin in strains isolated from the piglet after weaning.

The production of enterotoxin by biological tests (Yl adrenal cells and the suckling mouse) has been examined in 96 strains of Escherichia coli, isolated from sick piglets after weaning. There is a good correlation between the presence of the capsular antigen K88 and that of the thermolabile fraction (LT) of the enterotoxin (69.2 per cent of the enteropathogenic strains studied). However, the presence of the thermostable fraction (ST) of the enterotoxin of strains which, according to their serological grouping, possess in theory the two fractions LT + ST or only the ST fraction is only confirmed in a small number of strains (16 per cent) by the biological test.

Animals↗

[Topographic diagnosis of urinary infection by determination of fraction 5 of lactate dehydrogenase].

Amongst the various methods suggested for the topographical diagnosis of urinary tract infection, the study of various fractions of lactico-dehydrogenase in the urine would appear to be particularly valuable. Study of 44 subjects with a significant urinary infection, compared with an identical group of subjects free of urinary infection, showed that in those with pyelonephritis fraction 5 was significantly (p less than 0.001) higher than in those with a lower urinary tract infection. However this was valid only in the absence of renal insufficiency. Combined study of immunological techniques (urinary antibodies revealed by immunofluorescence and serum antibodies) shows that these techniques are complementary and make it possible to exactly localise the site of a urinary tract infection. In relation to immunology, enzymology has the advantage of being suitable for use during periods at which bacteriological examination of the urine is negative, and hence is useful in following the influence of treatment.

Adolescent↗

[Serum and urinary antibodies in pyelonephritis (author's transl)].

Pyelonephritis is accompanied by complex immunological reactions, the study of which is just now being undertaken. Study of 216 patients with a significant monomicrobial urinary infection showed that in more than 95 per cent of cases of Gram negative infection the urine contained IgG type antibodies, often associated with IgA. These antibodies may be easily detected using an immunofluorescent technique, which would appear to be the best method available at present for distinguishing between pyelonephritis and an infection of the lower urinary tract. They may also be found in the serum, though less frequently. Detection by immunofluorescence is markedly more sensitive than using the classical passive haemagglutination technique. The biological significance of these antibodies remains imprecise, and their protective or facilitating role may be discussed. Their specificity must be determined, in order that sequential study of these immunological reactions may be of help in the conduct of treatment.

Antibodies, Bacterial↗

Antibodies in Escherichia coli urinary tract infection.

In 105 adults with E.Coli urinary tract infections, IgG coated bacteriuria was found in 8/9 with acute pyelonephritis (PN), 17/20 with chronic PN, and in only 2/76 with lower UTI. IgA was present in 66% of PN, but IgA secretory piece in less than 10%. These urinary IgG antibodies were, at least in part, synthesised in the kidney because serum IgG antibodies were detected by indirect immunofluorescence in only half the patients. 06, 018, 022 E.Coli serotypes were the three most frequently found O groups, but their prevalence in PN is not significant. The immunology of urinary tract infection (UTI) is still a subject of little interest in adult nephrology; but antibody production is a well-characterised event in pyelonephritis (PN), the study of which seems to be the best indirect procedure for localising the site of UTI. We have analysed the production of urinary and humoral antibodies, and their correlation with E.Coli serotypes in patients with E.Coli UTI.

Adult↗

Detecting enteropathogenic Escherichia coli strains of porcine origin. 1. Correlations between O and K antigens and the enterotoxin production in strains isolated from the newborn piglet.

A study of enterotoxin production by means of biological tests (Y1 adrenal cells and suckling mice) using 67 Escherichia coli strains responsible for diarrhea in newborn piglets, confirmed the advantages of these methods and demonstrated the correlation between antigenic specificity and enterotoxin production. In particular the presence of capsular antigen K 88 is related to the thermolabile (LT) fraction of the enterotoxin in 73.9 % of the enteropathogenic strains studied.

Animals↗

Sclerosed liver hemangioma mimicking malignant tumor at MR imaging: pathologic correlation.

This case report illustrates atypical magnetic resonance (MR) imaging findings in a liver hemangioma mimicking a malignant lesion--lower signal intensity than cerebrospinal fluid on T2-weighted spin-echo images and lack of early enhancement on dynamic contrast material--enhanced gradient-echo images. Pathologic analysis demonstrated nearly total replacement of the vascular cavities by dense fibrous tissue. In this rare, sclerosed form, this lesion could not be defined as a hemangioma with MR imaging.

Adult↗