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M Bartoli

Publications and source records attributed to M Bartoli.

At least 37 records · Page 2Linked to original sources
PubMed1996

A novel calmodulin-binding protein, belonging to the WD-repeat family, is localized in dendrites of a subset of CNS neurons.

A rat brain synaptosomal protein of 110,000 M(r) present in a fraction highly enriched in adenylyl cyclase activity was microsequenced (Castets, F., G. Baillat, S. Mirzoeva, K. Mabrouk, J. Garin, J. d'Alayer, and A. Monneron. 1994. Biochemistry. 33:5063-5069). Peptide sequences were used to clone a cDNA encoding a novel, 780-amino acid protein named striatin. Striatin is a member of the WD-repeat family (Neer, E.J., C.J. Schmidt, R. Nambudripad, and T.F. Smith. 1994. Nature (Lond.). 371:297-300), the first one known to bind calmodulin (CaM) in the presence of Ca++. Subcellular fractionation shows that striatin is a membrane-associated, Lubrol-soluble protein. As analyzed by Northern blots, in situ hybridization, and immunocytochemistry, striatin is localized in the central nervous system, where it is confined to a subset of neurons, many of which are associated with the motor system. In particular, striatin is conspicuous in the dorsal part of the striatum, as well as in motoneurons. Furthermore, striatin is essentially found in dendrites, but not in axons, and is most abundant in dendritic spines. We propose that striatin interacts, through its WD-repeat domain and in a CaM/Ca(++)-dependent manner, with one or several members of a surrounding cluster of molecules engaged in a Ca(++)-signaling pathway specific to excitatory synapses.

Adenylyl Cyclases↗
PubMed1995

Myocardial viability: nuclear medicine versus stress echocardiography.

The failure of nonimaging techniques in the identification of myocardial viability has promoted the clinical application of radioisotopic and echocardiographic methods. Unfortunately, none of these techniques provides, per se, a 100% predictive accuracy and only few studies have been based on the postoperative improvement in regional wall motion, the absolute "gold standard" for myocardial viability. The recent thallium-201 protocols (reinjection, late redistribution, rest studies) have provided nuclear cardiology with a cell membrane integrity image able to unmask viable myocardium in more than 85% of viable segments. Sestamibi has been introduced as a nonrecirculating flow tracer able to detect transient ischemia as well as thallium-201. Its main limit, a high sensitivity to intermediate reductions in coronary blood flow, determines a high incidence of false positive studies. Positron emission tomography allows the evaluation of regional myocardial blood flow and metabolism. The marker of viable myocardium is the mismatch between reduced blood flow and normal or increased uptake of 18-F fluorodeoxyglucose. This technique allows the detection of viable tissue in most segments showing improved postoperative function. In our experience, applying a multiparametric approach, rest thallium-201 scan, rest sestamibi, dobutamine, and dipyridamole echocardiography showed a sensitivity and a specificity of 86%, 75%, 82%, 75% and 92%, 84%, 92%, and 89%, respectively, in the detection of residual viability. The main advantages of thallium-201 are reproducibility and standardization; those of stress echo are low cost and availability. In patients with severely depressed ventricular function, positron emission tomography retains a primary role when compared to thallium-201 and stress echocardiography.

Dipyridamole↗
PubMed1994

[In vitro bactericidal activity of seven antibiotics and four combinations against Neisseria meningitidis].

The authors studied, with a time-kill curve method, in a derived Hafiz medium broth the bactericidal effect of 7 antibiotics and 4 associations against N. meningitidis. Their results show a better bactericidal effect for penicillin G, ampicillin and chloramphenicol. Pefloxacin and ceftriaxon are less efficient. The association ampicillin + chloramphenicol in vitro shows no antagonism and has a good bactericidal activity at the early stages of bactericidal killing with N. meningitidis.

Ampicillin↗
PubMed1993

Effects of alpha-human atrial natriuretic peptide in guinea-pig isolated heart.

The aim of the present investigation has been to ascertain whether or not atrial natriuretic peptides (ANP) can exert a direct effect on myocardial contractility. Alpha-human ANP (alpha-hANP) concentrations ranging from 1 pM to 50 nM have been used to perfuse guinea-pig isolated hearts in a non-recirculating Langendorff apparatus. A dual concentration-related effect has been induced by alpha-hANP on myocardial function. A maximal increase of +LV dP/dtmax (+56%; P < 0.001) has been observed when guinea-pig hearts were perfused with 100 pM alpha-hANP, whereas a 25% decrease (P < 0.01) occurred with 50 nM alpha-hANP. Similar effects have also been induced by alpha-hANP on the coronary flow rate (CFR). A significant CFR increase (maximal at 10 pM alpha-hANP) was induced by picomolar concentrations of alpha-hANP, whereas a progressive decrease, which was maximal (-28%; P < 0.01) at 50 nM alpha-hANP, was observed with nanomolar concentrations of the peptide. No effects have been observed on heart rate. These results suggest that ANP has direct effects on both vascular and myocardial muscle cells. Coronary vasoconstriction induced by nanomolar concentrations of ANP can contribute to the cardiodepression, whereas ANP in picomolar concentrations can induce a coronary vasodilation which is not coupled with the enhanced myocardial contractility. The latter is the likely expression of a direct effect of the peptide on myocardial function.

Animals↗
PubMed1993

Does the myocardium become "stunned" after episodes of angina at rest, angina on effort, and coronary angioplasty?

To assess whether myocardial stunning occurs after brief periods of ischemia, global and regional ventricular function assessed by radionuclide angiography was studied in 52 patients. Patients were divided into 3 groups according to the type of ischemic episodes. Group 1 consisted of 15 patients studied before, during and after episodes of angina at rest. Seventeen patients studied immediately before and after coronary angioplasty constituted group 2. Group 3 consisted of 20 patients with stable angina studied before, during and after exercise-induced ischemia. Medical therapy was discontinued 48 hours before the study in all patients except those undergoing coronary angioplasty who were receiving diltiazem 180 mg/day. No difference in baseline ejection fraction was found between groups, whereas peak filling rate was statistically lower in group 3 patients. Evidence of left ventricular dysfunction during ischemia was seen in patients in groups 1 and 3, whereas transient ischemia was documented by ST-segment displacement and/or typical chest pain during balloon inflation in group 2. Persistence of systolic or diastolic dysfunction was not observed in any of the 3 groups in the recovery phase after ischemia. In conclusion, transient ischemia caused either by a primary reduction in oxygen supply (angina at rest, coronary angioplasty) or by an increase in oxygen demand (angina on effort) did not reproduce the phenomenon of systolic and diastolic stunning observed in animal experiments, although in all patients the ischemia was of sufficient duration and severity to induce marked ventricular dysfunction. The search for stunned myocardium should be extended to other different clinical models characterized by prolonged ischemia such as unstable angina or myocardial infarction.

Aged↗
PubMed1993

Ischemia on effort is not a determinant of stunned myocardium in man: a radioisotopic study based on quantitative evaluation of ventricular dynamics.

To assess whether myocardial stunning occurs following brief episodes of effort ischemia, ventricular function was assessed by radionuclide angiography in 29 patients with coronary artery disease. No patient had evidence of previous myocardial infarction. Patients were divided into two groups according to presence of single (14 patients, Group 1) or multi-vessel (15 patients, Group 2) coronary artery disease. Equilibrium radionuclide angiocardiography was performed in the left anterior oblique projection by a small field-of-view gamma-camera. Acquisition were performed at baseline, at peak exercise, then again at 1 and 5 minutes of the recovery phase. For each acquisition, ejection fraction, peak filling rate and wall motion index were measured and compared. No difference in baseline and stress measurements was found between Group 1 and Group 2, except for the wall motion index that was more impaired during ischemia in patients of Group 2. Global and regional indexes of ventricular function did not show significant differences also in the two recovery periods when compared to the relative baseline values. Transient ischemia caused by an increase of oxygen demand did not reproduce the phenomenon of systolic and diastolic stunning observed in animal experiments, although in all patients the ischemia was of sufficient duration and severity to induce transient ventricular dysfunction.

Adult↗
PubMed1993

[Evaluation of a micromethod for the bactericidal activity of five disinfectants on 108 hospital strains].

The authors studied 5 disinfectants containing aldehyde and quaternary ammonium against 108 hospital strains. The minimal bactericidal activities (MBC) were determined with a microdilution method and the dilution-neutralization method (AFNOR T 72-150). The microdilution method results were validated using the MBCs of four reference strains tested with the dilution-neutralization method (AFNOR T 72-150). 3 disinfectants proved to be valuable. 1 disinfectant was valuable but with a MBC toward all bacteria only a dilution away from the dilution of use. 1 disinfectant was determined as unsatisfactory as 9.5 p. cent of all strains proved resistant toward it. All disinfectants matched AFNOR standards; but those specifications did not match toward hospital strains. Such an evaluation using a simple and reliable method should be of use.

Acinetobacter↗
PubMed1992

Kinetic changes of ethanolamine base exchange activity and increase of viscosity in sarcolemmal membranes of hamster heart during development of cardiomyopathy.

The activity of the phospholipid base exchange enzyme specific for ethanolamine has been measured in cardiac sarcolemmal membrane preparations from Syrian golden and UM-X7.1 cardiomyopathic hamsters. In Syrian golden hamsters, the Km of the enzyme for ethanolamine does not change with age, whereas it almost doubles in membranes from cardiomyopathic animals, from the 30th to the 150th day of age. During the same period, the membrane cholesterol content increases by 68% in cardiomyopathic hamsters, whereas it does not change significantly in the Syrian golden hamster strain. As a consequence, in the adult animal, the cholesterol to phospholipid ratio and the viscosity of sarcolemmal membranes are higher in UM-X7.1 strain than in Syrian golden hamsters. A cause-consequence relationship between the enzymatic changes and the compositional modifications in the sarcolemma occurring in UM-X7.1 hamsters during the development of cardiomyopathy is proposed.

Animals↗
PubMed1992

[Incidence of nosocomial infections in a military hospital].

Over a 2-year period, 479 cases of nosocomial infections were identified in our hospital by a surveillance method based on the bacteriological laboratory results. The monthly incidence rate ranged from 1.8 to 4 percent of all in-patients. With this method, a 2 percent background noise and a 4 percent alarm threshold could be defined. The most frequent nosocomial infections were urinary tract infections (77 percent), purulent skin infections (12 percent) and septicaemias (10 percent). Compared during 15 days with the most sensitive surveillance method of the National Nosocomial Infections Surveillance System, our method proved insufficient to detect nosocomial lung infections and superficial surgical wound infections. On the other hand, it was highly satisfactory to watch for urinary tract infections and septicaemias. Improvements that would not put a heavy burden on the work of clinical departments are suggested.

Adolescent↗
PubMed1992

The chemoprophylaxis of cerebrospinal meningitis using rifampin in a military population.

Since February 5th 1990, the prevention of secondary cases of cerebrospinal meningitis (CSM) in France has been obtained by the use of rifampin. Following the detection of a case of N. meningitidis of antigenic formula B:NT:P1.15,16 in a military population, 89 contacts subjects received 600 mg rifampin twice a day during 2 days. Meningococcal carriage rate was investigated by nasopharyngeal swab sampling of the 89 subjects and 62 non-contact controls from the same community. Twenty-three days after the initial case of meningitis, carriage rate was 5.6% for treated subjects and 37.1 for controls. Sero-grouping, serotyping and subtyping failed to detect the initial virulent strain; it demonstrated the heterogeneity of circulating strains. Since rifampin-resistant mutants may occur, two strains in the treated group, it is essential that chemoprophylaxis in a community be limited strictly to the contact subjects.

Drug Resistance, Microbial↗
PubMed1991

Diagnosis of tuberculosis by DNA amplification in clinical practice evaluation.

Various polymerase chain reaction (PCR) assays have been devised for the rapid identification of mycobacteria in clinical specimens. To assess the value of such assays in routine laboratory work the results obtained by PCR were compared with those obtained by standard microbiological methods for 514 specimens collected for investigation of mycobacterial infection. Specimens were tested for the presence of Mycobacterium tuberculosis complex and atypical mycobacteria in two assays, one based on amplification of the 65 kDa gene and the other on the IS6110 insertion sequence. For the 489 samples that did not contain inhibitors of the amplification reaction PCR findings correlated well with bacteriological and/or clinical data in 476 (97.4%). 6 PCR results turned out to be false negatives, 3 to be false positives and 4 to be mis-identification of strains. Pre-treatment of samples with guanidium thiocyanate reduced the proportion of false-negative results and of samples that contained inhibitors. This study confirms the potential of DNA amplification for early diagnosis of mycobacterial infections.

DNA Probes↗
PubMed1986

[Proposal for a method of studying the activity of soap or antiseptic against the microbial flora of the hands after a single surgical scrub].

The authors, all members of the Antiseptics group of the Societé Française de Microbiologie, propose a standardised method for the evaluation of the activity of antiseptics on the microbial flora of the hands in the context of surgical scrubbing. This paper defines the aims of the method, its field of application and describes the media and materials required. The various phases of the preliminary study and the definitive trial also described.

Anti-Infective Agents, Local↗
PubMed1984

[In vitro virucidal activity of antiseptics and disinfectants. II. Simple dilution technic].

The simple dilution technique is based on termination of the tested agent's antiviral activity by sudden cold dilution (D). It can be used only if D less than or equal to 10(3) but is the most simple method. We used this technique to study ATS and demonstrate the strong virucidal activity of glutaraldehyde, inefficiency of chlorhexidine digluconate and questionable activity of povidone-iodine and noxythiolin.

Anti-Infective Agents, Local↗
PubMed1975

Histochemical study on systemic amyloid microdeposits with special reference to parathyroid intrafollicular deposits.

This study was carried out in order to define the histochemical behaviour of the substance present in follicles of normal parathyroid glands obtained at routine autopsies. It was noticed that these follicles with typical amyloid staining properties are constantly present in old persons; furthermore the amyloid in question presents histochemical characteristics which identify it as Apudamyloid. With this in mind we studied the possible, concomitant, systemic, amyloid microdeposits; we noticed that intrafollicular Apudamyloid of the parathyroid gland is often encountered together with immune deposits which are sometimes present in the same gland though not necessarily in the follicles.

Aged↗
PubMedDate not supplied

Selective ulnar nerve localization is not essential for axillary brachial plexus block using a multiple nerve stimulation technique.

BACKGROUND AND OBJECTIVES: The multiple-injection technique for axillary block, in which the 4 distal nerves of the plexus are located by a nerve stimulator and separately injected, has been shown to produce a rapid onset and a high success rate. However, this technique may be more difficult and time consuming than other axillary block methods. A simplified multiple-nerve stimulation technique, in which the ulnar nerve was not located, was compared in the present double-blind study to the 4-injection approach. METHODS: Eighty-four patients were randomly allocated to 2 groups. In group IV, all 4 distal nerves of the plexus were located by a nerve stimulator and injections made. In group III, all the nerves but the ulnar were located and injections made. The block was defined as complete when analgesia was present in all the sensory areas distal to the elbow. RESULTS: The time to perform the block was shorter in group III (5 +/- 2 v 8 +/- 3 minutes; P <.001). Block performance pain was lower in group III patients (8 +/- 2 v 13 +/- 2 mm; P <.001). The onset time (15 +/- 6 v 16 +/- 7 minutes) and the frequency (90% v 92%) of complete block were not different between the groups. CONCLUSIONS: A triple-injection method of axillary block in which the ulnar nerve was not purposely located provides a spread and a latency of sensory block equal to that obtained with a 4-injection technique. A shorter performance time is an advantage of this approach.

Adult↗