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Alvine Bissery

Publications and source records attributed to Alvine Bissery.

24 records · Page 2Linked to original sources

Pulmonary nodules: preliminary experience with three-dimensional evaluation.

PURPOSE: To evaluate software designed to calculate pulmonary nodule volume in three dimensions. MATERIALS AND METHODS: Fifty-four solid noncalcified pulmonary nodules measuring 5-18 mm in diameter were studied with computed tomographic (CT) volumetric software. Baseline CT examinations were performed for various indications by using four-detector row multisection CT units, 1.25- or 2.50-mm sections, and a standard reconstruction algorithm. The percentage of successful nodule segmentations, as well as intraobserver variability, interreader agreement, and global repeatability of calculated volumes, was determined on the basis of consecutive measurements performed three times by three different radiologists by using the Bland and Altman method. The software was used to calculate the doubling time of 22 nodules for which a final diagnosis and comparable CT scans were available. RESULTS: Fifty-two (96%) of the 54 nodules were successfully segmented, allowing their volume to be calculated. Repeatability was high: There was no variation in the nine measurements of 35 (67%) of the 52 nodules. The coefficient of variation for the remaining 17 nodules (33%) was 2.26%. Bland and Altman 95% limits of acceptability, calculated on the basis of log-transformed data, yielded a maximum software measurement error of 6.38% of the previous volume measurement. Doubling time ranged from 4 to 188 years for the 13 benign nodules and from 37 to 216 days for the nine malignant nodules. CONCLUSION: Software volumetric analysis yielded repeatable estimates for 96% of the nodules examined. All software-calculated doubling times were in keeping with the benign or malignant nature of the nodules.

Adult↗

Effect of a nationwide program of educational outreach visits to improve the processes of care for patients with type 2 diabetes.

OBJECTIVES: To improve processes of ambulatory care for patients with type 2 diabetes in a nationwide program. METHODS: Interrupted time-series analysis with audits of practice. To implement selected recommendations of national guidelines, educational outreach visits (office visits or phone discussions) were offered to all French physicians who diagnosed one case of type 2 diabetes during a six-month intervention period. Outcome measures were the number of HBA1c measurements recorded monthly in the medical insurance computer database and the proportion of diabetic patients for whom one test had been reimbursed during the previous six months (HBA1c, fasting blood glucose) or previous twelve months (serum cholesterol, serum creatinine, urine microalbumin, electrocardiogram, ophthalmologic examination). RESULTS: A total of 15,522 office visits and 9,062 telephone discussions were performed among 22,940 physicians. The increase in the monthly proportion of the number of HBA1c tests to the total number of laboratory tests was higher during the intervention period than during the preintervention (p value < .0001) and postintervention periods (p value < .001). Between the first audit (n = 651,574) and the third audit (n = 911,871), HBA1c measurements increased from 41.2% to 60.5% and blood glucose measurements performed alone decreased from 38.8% to 18.7%. Urine microalbumin measurements increased from 10.6% before to 15.3% after intervention. Only a slight increase was observed for other tests. CONCLUSIONS: Physician to physician outreach visits can be an effective way to improve the processes of care for diabetes and to routinize nationwide use of practice guidelines.

Ambulatory Care↗

Dual renin-angiotensin system blockade restores blood pressure-renin dependency in individuals with low renin concentrations.

BACKGROUND: The prevailing sodium intake and renin-angiotensin system status influence the blood pressure response to an angiotensin II type 1 (AT1) receptor antagonist or an angiotensin I converting enzyme inhibitor, which is known to be reinforced by a low sodium intake or administration of a diuretic. OBJECTIVE: To investigate the possibility that combining both drugs might be more effective in conditions of high sodium intake than blocking the renin-angiotensin system in a single step. METHODS: In a placebo-controlled, four-period crossover study in 12 normotensive volunteers who received a high sodium chloride intake (more than 250 mmol/day for 6 days), the haemodynamic and renin effects of a single oral dose of irbesartan 150 mg combined with fosinopril 20 mg were compared with those of a usual daily dose of fosinopril (20 mg) and a high dose of irbesartan (300 mg). RESULTS: The changes in blood pressure induced by fosinopril and irbesartan alone were not different from those of placebo, whereas the combination significantly decreased blood pressure. Simultaneously, it increased plasma active renin and prorenin concentrations to a greater extent than did each single-site blocker. CONCLUSION: In low-renin conditions, combined renin-angiotensin system blockade enables the demonstration of a persistent renin-dependency of the blood pressure. Through its more efficient blockade of the renin-angiotensin system, demonstrated by the increase in renin and prorenin, combined renin-angiotensin system blockade is more effective than doubling the usual dose of an AT1 receptor antagonist. This may offer an alternative strategy for treating patients with a range of renin concentrations, and may potentially increase the cardio- and nephrotective benefits through a more complete blockade of the renin-angiotensin system.

Adolescent↗

Physiologic consequences of vasopeptidase inhibition in humans: effect of sodium intake.

The in vivo inhibition of angiotensin-converting enzyme (ACE) and neutral endopeptidase (NEP) were monitored simultaneously by sequentially measuring the urinary excretion of N-Acetyl-Ser-Asp-Lys-Pro and of the atrial natriuretic factor to compare the magnitude and the duration of action of a vasopeptidase inhibitor, omapatrilat, and an ACE inhibitor, fosinopril. Single oral doses of 40 or 80 mg of omapatrilat or 20 mg of fosinopril were administered to 24 normotensive, sodium-depleted or -replete volunteers in a placebo-controlled crossover study. ACE inhibition persisted longer after treatment with omapatrilat than with fosinopril, and there was no major difference between the effects of 40 and 80 mg of omapatrilat. The duration of NEP inhibition by omapatrilat was shorter than that of ACE inhibition. Although omapatrilat effectively inhibited NEP, it had a mild and transient natriuretic effect and did not increase natriuresis more than fosinopril. Omapatrilat induced a decrease in BP and an increase in plasma renin more rapidly and more effectively than fosinopril. The BP and renin effects of omapatrilat persisted despite high sodium intake, which neutralized the effects of fosinopril. The simultaneous inhibition of ACE and NEP may be more effective in reducing BP than the inhibition of ACE alone and less dependent on sodium balance.

Adult↗

Transplantation of cardiac-committed mouse embryonic stem cells to infarcted sheep myocardium: a preclinical study.

BACKGROUND: Heart failure develops after myocardial infarction and is a major cause of morbidity and mortality. The ability to direct differentiation of embryonic stem cells (ESC) towards a cardiomyogenic phenotype makes them an attractive therapeutic option for cardiac repair, but species-specific and individual-specific immunological imprinting remains a hurdle. Our aim was to ascertain whether the purported immune privilege of ESC allows for their cross-species engraftment in a clinically relevant large-animal model. METHODS: We studied engraftment and differentiation of cardiac-committed mouse ESC in 18 sheep in which a myocardial infarction had been induced; nine controls received medium and nine sheep (five of which were immunosuppressed) received ESC. The gain in myocardial function was measured by echocardiography 1 month after cell transplantation. FINDINGS: Cardiac-committed murine ESC engrafted in infarcted myocardium of immunosuppressed and immunocompetent sheep, and differentiated into mature cardiomyocytes that expressed connexins. Colonisation of the scar area by ESC was accompanied by a functional benefit of the damaged myocardium. Left-ventricular ejection fraction deteriorated in the control group by a median of 9.9% (range -20 to 0.3) relative to baseline (p=0.011) whereas in the treated group it improved by 6.6% (-5.7 to 50.8; comparison between groups p=0.002). INTERPRETATION: These findings obtained in a clinically relevant large-animal model of heart failure strengthen the potential therapeutic use of ESC to regenerate the severely dysfunctional myocardium and bring additional evidence for an immune privilege of these cells.

Animals↗