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M Paris

Publications and source records attributed to M Paris.

At least 19 recordsLinked to original sources
PubMed2006

First-principles calculations within periodic boundary conditions of the NMR shielding tensor for a transition metal nucleus in a solid state system: The example of 51V in AlVO4.

We present the first density functional theory based calculations of NMR shielding parameters for a transition metal nucleus using periodic boundary conditions. These calculations employ the gauge-including projected augmented-wave pseudopotential approach. The quality of this method is discussed by comparing experimental and calculated chemical shift tensor eigenvalues for the quadrupolar 51V nucleus in the diamagnetic solid-state compound AlVO4. Furthermore, the combination of shielding tensor with fast and accurate projector augmented-wave electric field gradient tensor calculations allows us to determine the relative orientation of these two tensors.

Letter↗
PubMed2006

[Percutaneous treatment of cystic lymphangiomas].

Management of cystic lymphangioma necessitate for optimal diagnosis and treatment the expertise of a trained multidisciplinary team including dermatologists, radiologists, plastic and vascular surgeons. An initial imaging work-up of these lesions by ultrasound Doppler examination and MR imaging are necessary before treatment planning. Depending of the size, the location, the risk for the adjacent organs, a therapeutic decision may be mandatory. Percutaneous sclerotherapy is a safe and efficient treatment. It is the treatment of choice that must be proposed in first intention.

Age Factors↗
PubMed2003

A steady-state model for the evaluation of disk rotational speed influence on RBC kinetic: model presentation.

The physical and biological mechanisms of attached-biomass growth were analyzed and a steady-state model was proposed to determine the soluble carbonaceous removal in an RBC unit for different organic loading rates in the reactor. The objective of the model was the prediction of the organic loading rate corresponding to the maximum removal capacity in the system. A system of equations was solved where the influent soluble carbonaceous substrate concentration was the main variable. Monod's rate law was used for the growth of microorganism: the soluble carbonaceous substrate was the limiting substrate. Endogenous decay was neglected. The influence of disk rotational speed on the RBC removal capacity was investigated, the disk rotational speed being a parameter acting on oxygen transfer in the biofilm. The criteria for the evaluation of the kinetic parameter in the model were proposed.

Bacteria↗
PubMed2003

[Manubrio-sternal arthritis and behcet's disease: report of 3 cases].

Manubrio-sternal joint involvement in arthritis is described and may be evidenced by erosion, reactive sclerosis and ankylosis. Some reports of such involvement appear in the radiological literature in association with psoriatic arthritis and spondylarthropathy. Involvement of the manubrio-sternal joint in Behçet's disease is very uncommon. To our knowledge, only one case has been described. We report a case of manubrio-sternal arthritis in a women with Behçet's disease. Two others cases with suspicion of Behçet's disease are described.

Adult↗
PubMed2002

Breast cancer risk in healthy and symptomatic women: results of a multivariate analysis. A case-control study.

Several risk factors for breast cancer (BC) have been investigated in different reports, but none has been really useful in preventing BC development. The aim of this study was to evaluate the risk of BC in self-selected symptomatic women in comparison with the healthy population residing in an urban area of Italy. A group of 404 women (median age 59 years, range 26-89 years) with confirmed BC (cases) were age-matched with 389 healthy women (Group A), and 391 (Group B) symptomatic non-screened patients without BC, who were referred to our Breast unit. The results of univariate analysis showed a significant (P < 0.01) difference between cases and controls in (1) age at menarche, (2) number of birth and age at first births, (3) lactation and months of lactation, and (4) estrogen replacement therapy (ERT) and duration of ERT. Multivariate analysis using a logistic regression model adjusted for age showed that five independent parameters (no pregnancy, age at first birth > 30 years, no lactation, use of ERT, ERT > 40 months) significantly (P < 0.01) correlated with BC onset. The relative odds ratios (ORs) at 95% confidence interval (95% CI) were 5.25, 2.47, 2.82, 2.80, and 5.56, respectively. The cumulative OR (95% CI) calculated from the observed vs. predicted values was 7.15. No differences (P = NS) were found between groups A and B. In conclusion, in our study population, the prolonged use (> 40 months) of ETR in menopausal women resulted in an increased risk of BC, and represented the only risk factor that could be removed.

Adult↗
PubMed2001

NMR local range investigations in amorphous starchy substrates I. Structural heterogeneity probed by (13)C CP-MAS NMR.

The (13)C CP-MAS (Cross Polarization and Magic Angle Spinning) NMR signatures of a series of amorphous and semi-crystalline samples prepared from various starchy substrates (native potato starch, amylopectin, amylose) following different techniques of preparation (casting, freeze drying, solvent exchange) are compared. Decompositions of the C1 resonance spectra reveal the existence of four or five main types of alpha(1-4) linkages, which can be quantified. The influence of the intrinsic primary structure (linear or branched) and of the preparation procedure on conformational changes and resulting crystallinity are interpreted in terms of distributions of average glycosidic linkages dihedral angles (Phi, Psi). The role of hydration is also considered. An improved understanding at different structural levels is obtained in relation to local and intermediate range orders. Such information may be useful for the understanding of the structural evolution of a large variety of starchy substrates before or after treatments widely used in industrial processes.

Amylopectin↗
PubMed2001

NMR local range investigations in amorphous starchy substrates: II-Dynamical heterogeneity probed by (1)H/(13)C magnetization transfer and 2D WISE solid state NMR.

In the preceding paper, we have investigated the structural heterogeneous character of a series of amorphous samples prepared from various starchy substrates (native potato starch, amylopectin and amylose) following different techniques of preparation (casting, freeze drying and solvent exchange). Spectral decompositions of the C1 resonances of the (13)C CP-MAS (Cross Polarization and Magic Angle Spinning) spectra under (1)H decoupling have shown the existence of five main types of alpha(1-4) linkages. In this part, 2D solid state NMR WISE experiments and the (13)C/(1)H magnetization transfer in CP as a local probe for both structures and dynamics were used. The (13)C CP magnetization curves versus contact time of each C1 component in each recorded spectrum were fitted with an analytic function taking into account two (1)H reservoirs. Interpretation of the characteristic times derived from fitting yields some improvements on the knowledge of the heterogeneity of the samples and on the water molecules distribution.

Amylopectin↗
PubMed2001

Cryopreservation of mouse ovarian tissue following prolonged exposure to an Ischemic environment.

In cases in which ovarian tissue is to be cryopreserved for tissue or gene banking it is important to maintain its integrity and viability. This study examined how delays between the death of an animal and the collection/cryopreservation of its ovarian tissue influenced follicle viability. Mouse ovaries were placed in PBS+antibiotic (in vitro) or left within the body (in situ) at room temperature for 0, 3, 6, 12, or 24 h following the death of the donor. These ovaries were cryopreserved at 1 degrees C/min on dry ice or in a -84 degrees C freezer using a passive cooling device or by conventional slow cooling (0.3 degrees C/min). The ovaries were grafted under the kidney capsule of ovariectomized recipient mice and collected 2 weeks later, and the size and number of follicles were determined. Cryopreserved ovarian tissue grafted immediately after the death of the donor contained numerous viable and healthy follicles independent of the cooling procedure (dry ice, 134 +/- 32; -84 degrees C, 165 +/- 54; slow, 214 +/- 55 follicles per half ovary). Tissues stored in vitro before cryopreservation retained viable follicles up to 12 h after death (dry ice, 30 +/- 15; -84 degrees C, 86 +/- 45; slow, 93 +/- 33), whereas tissue left in situ had significantly reduced follicle numbers within 3 h of death (dry ice, 36 +/- 12; -84 degrees C, 19 +/- 6; slow, 28 +/- 7). No significant difference was found between the cooling rates tested, indicating that a passive cooling container which cools at 1 degrees C/min is a suitable alternative to conventional slow cooling. We conclude that ovarian tissues for cryobanking should be cryopreserved as soon as possible after collection or death of the animal to ensure maximal follicular survival.

Animals↗
PubMed2001

Vapornomics.

Explore the source record for details and available documents.

Biotechnology↗
PubMed2001

Comparison of the effects of in vitro and in situ storage on the viability of mouse ovarian tissue collected after death.

Ovarian tissues, collected or salvaged from endangered species at the time of gonadectomy or following their death, are being transported to genebanks for storage with the assumption that they will (subsequently) yield sufficient numbers of germ cells to help preserve the species. The present study aimed to quantify the impact of delays in collecting and/or processing ovarian tissue on the number of follicles in this tissue that remained normal after grafting. The study compared the viability of ovarian tissue stored in vitro (in phosphate-buffered saline) versus in situ (in the body) either on ice or at room temperature for 0 (non-stored fresh grafts), 3, 6, 12, 24 or 48 h. The conditions of storage had significant effects on the total number of morphologically normal follicles, with significantly more follicles in grafts developing from in vitro-stored tissue than in situ-stored tissue. Storage temperature and duration of storage, but not the storage temperature alone, influenced follicle survival. Tissue that was grafted immediately after collection (0 h) was best, but normal follicles were recovered in grafts stored in vitro (on ice or at room temperature) or in situ (on ice only) for up to 48 h before grafting. The rate of follicle loss over time was very rapid, with approximately 50% fewer follicles in grafts derived from tissue stored for only 3 h compared with non-stored fresh grafts (0 h). The results show that viable ovarian tissue can be salvaged from animals up to 48 h after death; however, in order to best protect the follicle population, the ovaries should be removed from the animal's body as soon as possible.

Animals↗
PubMed2001

Cardiac troponin I: its contribution to the diagnosis of perioperative myocardial infarction and various complications of cardiac surgery.

OBJECTIVE: To study the value of assaying cardiac troponin I (cTnI) for the early diagnosis of perioperative myocardial infarction (PMI) and various complications of cardiac surgery. DESIGN: A prospective observational clinical study. SETTING: Biochemical laboratory, anesthesia, and cardiac surgery department of Hôpital Broussais. PATIENTS: Two hundred and sixty consecutive patients undergoing cardiac surgery. INTERVENTIONS: All patients underwent coronary artery bypass grafting and/or valvular surgery under extracorporeal circulation. Per-operative and postoperative follow-up consisted of electrocardiogram, echocardiography (mainly by the transesophageal approach), and serial determinations of biochemical markers such as creatinine kinase-MB isoenzyme (CK-MB) and cTnI. PMI, new ST segment changes, and ventricular arrhythmias were considered postoperative adverse cardiac outcome. MEASUREMENTS AND MAIN RESULTS: CTnI was measured before cardiopulmonary bypass (T0) and 12 and 24 hrs after (T12, T24). CK-MB was measured on arrival in the intensive care unit and on the first postoperative day (D1). Patients were divided into three groups according to the type of surgery: coronary artery bypass graft (CABG), valvular surgery (VS), or both procedures. The plasma CK-MB and cTnI concentrations were high in all patients after extracorporeal circulation because of aortic clamping or cardioplegia. The CK-MB and cTnI values were higher in the VS group than in the CABG group. Values peaked at T12 and fell by T24, except when PMI occurred. Eight patients developed a PMI. Patients with PMI had significantly higher cTnI levels at T12 and T24, and higher CK-MB values at D1 than patients without PMI. Cutoff values of cTnI for diagnosing PMI were >19 microg/L at T12 with 100% sensitivity and 73% specificity, and >36 microg/L at T24, with 100% sensitivity and 93% specificity. Lower cTnI values were highly suggestive of the absence of PMI after CABG and/or VS. Other complications such as ST segment changes, ventricular arrhythmias and cardiac failure were indicated by high cTnI levels at T12 and T24. Myocardial protective measures were associated with a nonsignificant increase in cTnI values. CONCLUSIONS: CTnI is more sensitive and specific than CK-MB for diagnosing PMI and other forms of heart failure after cardiac surgery.

Aged↗
PubMed2001

Motorcycle taxi drivers and sexually transmitted infections in a Peruvian Amazon City.

BACKGROUND: In Iquitos, Peru, motorcycle taxis are a common form of public transportation used both by residents and visitors. GOAL: To evaluate the prevalence of factors associated with sexually transmitted disease risk and of Neisseria gonorrhoeae and Chlamydia trachomatis infections among motorcycle taxi drivers working in Iquitos, Peru. STUDY DESIGN: A convenience sample of motorcycle taxi drivers was recruited through street outreach. Participants were confidentially interviewed and provided urine specimens for gonococcal and chlamydial infection testing. RESULTS: A history of sexually transmitted disease (62%) or symptoms in the past year (35%) and of referral of clients to commercial sex workers (60%) was common. The prevalence of gonococcal or chlamydial infection was 3.5%. CONCLUSIONS: Motorcycle taxi drivers are a major means of public transportation in Iquitos, Peru, have high personal risks for sexually transmitted disease, and interface often with at-risk persons.

Adolescent↗
PubMed1999

Some of the amino acid chemistry going on in the Laboratory of Amino Acids, Peptides and Proteins.

Some of the chemistry of amino acids going on in our laboratory (Laboratoire des Amino acides Peptides et Protéines) is described as well as some mass spectrometry methodology for their characterization particularly on solid supports. Several aspects are presented including: (i) the stereoselective synthesis of natural and unnatural amino acids using 2-hydroxypinan-3-one as chiral auxiliary; (ii) the stereoselective synthesis of natural and unnatural amino acids by deracemization of alpha-amino acids via their ketene derivatives; (iii) the synthesis of alpha-aryl-alpha-amino acids via reaction of organometallics with a glycine cation; (iv) the diastereoselective synthesis of glycosyl-alpha-amino acids; (v) the synthesis of beta-amino acids using alpha-aminopyrrolidinopiperazinediones as chiral templates; (vi) the reactivity of urethane-N-protected N-carboxyanhydrides. To characterize natural and non natural amino acids through their immonium ions by mass spectrometry, some methodology is also described.

Amino Acids↗
PubMed1999

Conversion of failed ileal pouch-anal anastomosis to continent ileostomy.

PURPOSE: We report the results of converting 42 failed ileal pouch-anal anastomoses to a continent ileostomy (using the Barnett modification of the Kock pouch) performed in the course of 1,334 consecutive continent ostomy procedures. METHOD: Results were obtained from a data registry that tracks long-term outcomes of consecutive continent ostomy procedures performed by 12 surgeons in five centers in the United States. RESULTS: Forty of the 42 patients with failed ileal pouch-anal anastomoses have a functioning continent ostomy. Two patients have had pouch excision. Quality of life for the patients with ileal pouch-anal anastomoses as measured by the SF-36 index improved postoperatively. Long-term outcomes for the patients with ileal pouch-anal anastomoses were similar to those for the larger population of patients who underwent the continent ostomy procedure for other reasons. CONCLUSION: Conversion of a failed ileal pouch-anal anastomosis to a continent ileostomy is a satisfactory alternative to the Brooke ileostomy in appropriate cases.

Adult↗
PubMed1999

Does aprotinin modify the effects of ischaemia-reperfusion on the myocardial performance of a blood perfused isolated rabbit heart?

Aprotinin has been reported to influence positively or negatively the process of ischaemia-reperfusion. However, it is a complex drug acting on platelets, neutrophils and coagulation, which may also have a direct effect by inhibiting intracellular proteases and free radical generation. The goal of this study was to determine the direct effects of aprotinin on the myocardial performances of an isolated blood perfused rabbit heart preparation after normothermic global ischaemia. Two groups of 10 hearts were studied. The control group (ischaemia) underwent 30 min of global normothermic ischaemia. In the aprotinin group, (aprotinin) 200 KUI mL-1 of aprotinin was added to the perfusate before ischaemia. Measurements were obtained at base-line, 10, 30 and 60 min after reperfusion. Normothermic ischaemia significantly decreased myocardial performance in both groups. After 60 min reperfusion, myocardial contractility significantly recovered in the aprotinin group compared with the ischaemia group. Aprotinin contributes significantly by limiting the consequences of ischaemia on myocardial performances. This effect may be due to a direct action of the drug because leucocytes and plasma proteins were removed in this preparation.

Animals↗
PubMed1999

Comparison of the acute hemodynamic effects of hypertonic or colloid infusions immediately after mitral valve repair.

OBJECTIVE: To determine the acute hemodynamic effect of hypertonic saline and/or colloid solutions as volume resuscitation in postoperative mitral valve repair patients. DESIGN: Prospective, randomized trial. SETTING: Postoperative cardiac intensive care unit of Broussais Hospital. PATIENTS: Twenty-six patients who underwent mitral valve repair were prospectively studied. Two patients were excluded during the study. INTERVENTIONS: During the immediate postoperative period, when wedge pressure decreases to <8 mm Hg, patients were randomly assigned to receive 250 mL of either hypertonic saline 7.2%-hydroxyethyl starch 6% (molecular weight, 200,000; hydroxyethylation ratio, 0.5) solution (HS-HES group), hypertonic saline 7.2% solution (HS group), or hydroxyethyl starch 6% solution (HES group). The infusion was completed within 15 mins. No additional volume was infused throughout the study. MEASUREMENTS AND MAIN RESULTS: Standard hemodynamic measurements and echocardiographic data demonstrated that HS-HES and HS induced a higher increase in left ventricular end-diastolic area than HES. In the HS-HES and HS groups, systemic vascular resistances decreased significantly and end-systolic area tended to decrease. In the HES group, systemic vascular resistances did not change and end-systolic area tended to increase. Accordingly, ejection fraction increased significantly by 21% and 18% with HS-HES (from 50.5 +/- 5.5 to 61.2 +/- 4.8) and HS (from 49.7 +/- 3.6 to 58.8 +/- 3.3), respectively, and did not change with HES. A major increase in cardiac index was observed after hypertonic solutions infusion, from 2.9 +/- 0.3 to 4.1 +/- 0.4 L/min/m2 in the HS-HES group and from 2.7 +/- 0.3 to 3.8 +/- 0.4 L/min/m2 in the HS group. Then, cardiac index progressively returned to baseline values within the 3 hrs after the infusion. No significant difference was observed between HS-HES and HS. In these groups, plasma sodium increased significantly after the infusion and remained higher than baseline values throughout the study. Adverse events were observed only with hypertonic solution administration: hypotensive episodes, sudden increases in pulmonary capillary wedge pressure, and ventricular arrhythmias. These side effects are likely attributable to a too-high dose and/or rate of infusion. All patients included in the study were discharged from the hospital before the 10th postoperative day. CONCLUSION: We conclude that in patients who have undergone mitral valve repair, postoperative infusion of hypertonic saline solutions increases left ventricular preload and left ventricular ejection fraction. The use of these hypertonic solutions may be of interest in patients with valvular cardiomyopathy. A titrated dose and a low rate of infusion may substantially improve the safety.

Cardiac Surgical Procedures↗