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M T Labro

Publications and source records attributed to M T Labro.

64 records · Page 4Linked to original sources
PubMed1986

Effects of cefotaxime and cefodizime on human granulocyte functions in vitro.

In vitro, cefotaxime and cefodizime enhanced significantly the bactericidal activity of human neutrophils against Staphylococcus aureus P 209 A, but not phagocytosis. The increase was about 150% for cefotaxime and 400% for cefodizime at concentrations as low as 1 mg/l. Furthermore, by two different techniques (NBT and cytochrome C reduction tests) cefotaxime but not cefodizime significantly enhanced superoxide anion production by zymosan-stimulated neutrophils. Other neutrophil functions (chemotaxis and myeloperoxidase-mediated iodination of proteins) were not significantly altered by either antibiotic, even at concentrations as high as 1000 mg/l.

Blood Bactericidal Activity↗
PubMed1986

Synergy between RU 28965 (roxithromycin) and human neutrophils for bactericidal activity in vitro.

The in vitro effects of RU 28965 (roxithromycin), a new semisynthetic macrolide, on human neutrophil activity were compared with those of erythromycin. RU 28965, at a concentration as low as 0.1 microgram/ml, significantly enhanced the phagocytosis and killing of Staphylococcus aureus by neutrophils. Erythromycin displayed a less stimulating effect in a dose-dependent manner. Phagocytosis of Klebsiella pneumoniae was also increased after incubation of neutrophils with RU 28965, but killing was not altered. Neutrophil chemotaxis, myeloperoxidase activity, and O2 consumption were unchanged in the presence of RU 28965.

Blood Bactericidal Activity↗
PubMed1984

Detection of antilymphocyte antibodies in patients with scleroderma using three different techniques.

The occurrence of antilymphocyte antibodies (AL-Ab) was investigated in the sera of 28 patients with scleroderma. By indirect immunofluorescence, we found these Ab in 53% of the sera. Inhibition of E rosette formation and lymphocytotoxicity revealed these Ab in 42% and 14% of the sera respectively. Most of the Ab (93%) reacted at 0 degrees C. These AL-Ab can be separated into several groups depending on their inhibitory activity on the lymphocyte membrane. In some cases, the receptor seems similar to that of sheep red blood cells. The study of the clinical features of the patients showed few differences between the groups with and those without Al-Ab. It must be noted that all the patients with the CREST syndrome (6 cases) possessed Al-Ab.

Antilymphocyte Serum↗
PubMed1983

[Antinuclear, anti-DNA and anti-lymphocyte antibodies in systemic scleroderma. 62 cases].

The authors describe a prospective study of serum immunological abnormalities in 62 cases of systemic sclerodermia. Antinuclear antibodies were found in 67 percent of the cases. Contrary to expectation, the homogenous type was the most common. Anticentromeric antibodies were found in 4 of the 10 CREST syndrome patients. Anti-RNP (2/62) and natural anti-DNA antibodies are rarely found in sclerodermia. Non-cytotoxic anti-lymphocytic antibodies were found in more than half of the serums studied. They were frequently found in the CREST cases and in cases associated with Gougerot-Sjögren syndrome. Their significance is unknown. Lastly, almost all of the cases of systemic sclerodermia showed an immunological serum abnormality.

Antibodies, Antinuclear↗
PubMed1982

Chemokinetic activity of N-formyl-methionyl-leucyl-phenylalanine on human neutrophils, and its modulation by phenylbutazone.

Phenylbutazone (PBZ) is known to inhibit the oriented migration of human polymorphonuclear leukocytes (PMNs) induced by formyl-methionyl-leucyl-phenylalanine (FMLP), and to protect these cells against the deactivation caused by their prior incubation with FMLP. To gain insight into the mechanism of these effects, we measured the oriented PMN migration under agarose induced, in the presence and absence of PBZ, by FMLP, zymosan-activated serum and Klebsiella pneumoniae culture supernatant. The two components of this migration, i.e. the speed (chemokinesis), and direction of locomotion (chemotaxis), were also assessed. At concentrations ranging from 10(-8) to 10(-5) M, FMLP displayed similar chemotactic activity but the speed of PMN locomotion was maximal for 10(-7) M, and lower for concentrations above and below this level. Oriented migration was proportional to the mean cell locomotion speed during the experiments. PBZ inhibited both the oriented migration and locomotion speed induced by 10(-7) M FMLP, but did not affect its chemotactic activity. At concentrations of 10(-6) and 10(-5) M, PBZ increased oriented migration and locomotion speed, again without influencing FMLP chemotactic activity. Oriented migration induced by zymosan-activated serum was not affected by PBZ but the migration induced by Klebsiella pneumoniae culture supernatant diminished slightly. These results demonstrate that PBZ modulates the chemokinetic effect of FMLP on PMNs and thus alters oriented PMN migration.

Chemotaxis, Leukocyte↗
PubMed1981

[Role of Clostridium and its toxin in pseudo-membranous colitis (author's transl)].

At present many authors consider that pseudo-membranous colitis is of bacterial origin. The main pathogenic agent is Clostridium difficile. It is not easy to isolate this organism in the stool, selective media are under study. It liberates a lipo-glycoprotein exotoxin during lysis. It is only partially purified, its structure is not fully elucidated. Its molecular weight is not yet precisely determined. It consists of several polymerised polypeptide fragments of molecular weight 50 000. It is a thermolabile acid and alkaline sensitive cytotoxin which acts on the cell membranes and the ileo-caeco-colonic mucosa of man and animals. Clostridium difficile is transmissible by a small number of high risk carrier subjects who are potentially patients with pseudo-membranous colitis. Antibiotic therapy may lead to unbalance of the ecosystem represented by the bacterial flora of the digestive tract and favour the multiplication of a resistant strain to the administered antibiotic. The appearance of pseudo-membranous colitis requires the association of sufficient bacterial development (equal or greater than 10(7) germs per gram of stools) and the liberation of a cytotoxin. The pathogenic treatment consists of antibiotic therapy by Vancomycin or Metronidazole which seems, at present, the most active on the germs and a toxin absorbent, such as Cholestyramine, Coliptol hydrochloride or Heavy metals.

Animals↗
PubMed1978

A new pattern of non-organ- and non-species-specific anti-organelle antibody detected by immunofluorescence: the mitochondrial antibody number 5.

About 0.1% of the sera in human pathology produce a peculiar, cytoplasmic, non-organ- and non-species-specific fluorescence. This may easily be differentiated from the already described anti-organelle antibodies and, more particularly, from the mitochondrial antibodies of primary biliary cirrhosis. Should rat tissues be used in the immunofluorescence test, fluorescence predominates over the first two portions of the renal proximal tubules (P1 and P2) and the mucous neck cells of the stomach. This pattern may be atrributed to mitochondria, and in particular to their inner membranes by fluorescent staining of the ellipsoid region of the rods and cones of the eyes, and by absorption with purified organelles. To distinguish this antibody from the already described mitochondrial antibodies, this one will be called mitochondrial antibody number 5 (M5). The seven carriers of this antibody suffer from systemic lupus erythematosus or autoimmune haemolytic anaemia. In these cases no diseases of the liver were observed, contrary to other classical mitochondrial antibodies.

Adult↗
PubMedDate not supplied

[Macrolides and immunity].

In order to counteract an ever increasing bacterial resistance, a new trend in antibiotic therapy is to try and obtain compounds with "immunostimulating" properties. Although the macrolides have been known for more than 30 years, their interaction with the host defence system has been poorly investigated. These drugs display an outstanding ability to penetrate and concentrate in phagocytes. Few depressive effects on phagocyte functions have been reported, while some macrolides have been shown to exert an immunostimulating effect in vitro and ex vivo. The data published on this subject are summarized in this review paper. Further studies would be required for a better understanding of structure-immunomodulating activity relationships.

Adjuvants, Immunologic↗
PubMedDate not supplied

Antilymphocyte antibodies in progressive systemic sclerosis.

Sera from 19 patients with scleroderma were tested for antilymphocyte antibodies (ALA) by indirect immunofluorescence assay. ALA were found in 47% of the cases when tested at 0 degrees, and in 27% at 25 degrees C. Anti-T cell specificity was shown after separation of B and T cells. The heterogeneity of the ALA detected was clear both among different patients and in serum from the same patient. A monoclonal antibody (UCHT1) inhibited ALA binding to T cells completely in one case, and partially in another three, implying that with these 4 sera, the lymphocyte receptors for ALA were either identical or very close to the UCHT1 receptor. This study defines another immunological abnormality in scleroderma: the presence of cold-reactive anti-T cell specific ALA. Their pathogenicity requires further investigation.

Antibodies↗