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M Bertrand

Publications and source records attributed to M Bertrand.

At least 19 recordsLinked to original sources
PubMed2006

Low negative predictive value of dobutamine stress echocardiography before abdominal aortic surgery.

BACKGROUND: According to previous studies, a negative dobutamine stress echocardiography (DSE) test before major vascular surgery indicates that postoperative myocardial necrosis is very unlikely. We believe that the use of new cardiac troponin assays which can detect small amounts of myocardial necrosis results in a lower DSE negative predictive value for myocardial necrosis. METHODS: A total of 418 consecutive patients were screened using the ACC/AHA Guideline for Perioperative Cardiovascular Evaluation for Noncardiac Surgery before scheduled abdominal aortic surgery. Of these 143 met ACC/AHA criteria for non-invasive testing and underwent DSE. Patients with a negative DSE were deemed to be fit for surgery. A positive DSE led to a coronary angiogram. DSE was negative in 110 (77%) and positive in 33 (23%) patients. Myocardial necrosis was monitored up to the third postoperative day by daily cardiac troponin I (cTnI) measurement and a daily 12-lead ECG. RESULTS: Coronary angiography showed artery stenosis in 27 (84%) of 32 patients with a positive DSE. The negative predictive value of DSE for cTnI elevation was 92.7% (95% CI 86.2-96.8%). This was significantly lower than the lowest value of negative predictive value for myocardial necrosis assessed in previous studies. CONCLUSION: A negative DSE prescribed before scheduled aortic surgery according to ACC/AHA guidelines does not rule out postoperative myocardial necrosis.

Adult↗
PubMed2006

Comparison of liquid chromatography and capillary electrophoresis methods for quantification of sodium residuals.

Liquid chromatography (LC) and capillary electrophoresis (CE) methods were developed to perform the determination of residual sodium in mother liquors and successive washes of an active pharmaceutical ingredient (API). The addition of sodium chloride to the product solution results in rapid and complete crystallization of the API. The LC method was coupled to evaporative light scattering detection (ELSD) while the CE approach was based on indirect UV detection. Both methods were fully validated. Selectivity, response function, trueness, precision, accuracy, linearity and limits of detection (LOD) and quantification (LOQ) were the criteria investigated. The LC-ELSD method was found to be more sensitive than the CE/indirect UV approach. The methods were found to be valid over concentration ranges of 62-500 and 235-1500 ppm for the LC and the CE methods, respectively. Both methods were compared and used for the determination of actual samples coming from different batches of the same API chemical synthesis.

Chromatography, Liquid↗
PubMed2005

Long-term achievement of the therapeutic objectives of lipid-lowering agents in primary prevention patients and cardiovascular outcomes: an observational study.

AIMS: Lowering elevated cholesterol levels reduces cardiovascular (CV) morbidity and mortality. Nonetheless, most patients treated with lipid-lowering agents (LLA) do not reach recommended therapeutic objectives. In a setting of primary care in France, we investigated the association between LDL-cholesterol goal attainment and the occurrence of CV events in primary prevention patients with multiple CV risk factors (> or = 3). According to national guidelines, the therapeutic objective (TO) for such patients is an LDL-cholesterol value below 130 mg/dL. METHODS: 579 patients treated with LLA and with LDL-cholesterol values documented at least once a year over a period of at least 3 years (2000-2002) were allocated to three groups based on the number of years the TO was attained during the follow-up period: in all 3 years (TO+++: n=145), only part of the time (TO intermediate: n=256), and never (TO---: n=178). CV events (angina pectoris, myocardial infarction, heart failure, stroke, peripheral artery disease) occurring during the last year of observation (2002) were retrospectively collected. The occurrence risk (OR) of CV events was assessed based on TO status, with a logistic regression model to adjust for baseline differences in CV risk factors. RESULTS: Only a quarter of patients attained TO during all 3 study years. CV events during the third year of observation occurred in 5.5%, 10.5% and 12.9% of patients in the TO+++, TO intermediate and TO--- groups, respectively. Compared with TO+++ patients, the risk of CV events increased significantly in TO intermediate (OR=2.34, 95% CI=[1.01-5.39]) and TO--- patients (OR=2.99, 95% CI=[1.26-7.08]). CONCLUSION: In real practice, a prolonged attainment of TO is rarely observed in high CV risk patients treated with LLA as primary prevention. Therapeutic failure is related to an increased incidence of cardiovascular morbidity. Our data strongly support the need to improve adherence to treatment guidelines to achieve effective cardiovascular prevention.

Aged↗
PubMed2005

Ineffectiveness of lipid-lowering therapy in primary care.

BACKGROUND: Evidence confirms the positive effects of lipid-lowering agents on the risk of cardiovascular disease. Local guidelines in France (AFSSAPS) have defined therapeutic objectives for LDL-cholesterol. These objectives vary with the number of cardiovascular risk factors in addition to dyslipidaemia. We determined the proportions of patients at therapeutic objective in different classes of cardiovascular risk to test the hypothesis that compliance with guidelines varies across the levels of risk. Comparison with international guidelines (ANDEM) was also performed. METHODS: A group of 3173 dyslipidaemic patients treated with lipid-lowering agents and managed by general practitioners was randomly selected from BKL-Thales panel, a French computerized database. For each patient, history of coronary heart disease and the number of cardiovascular risk factors were documented. Compliance with guidelines was assessed from achievement of therapeutic objective. RESULTS: The study population included 79% primary prevention patients (1.6, 25.5, 31.7 and 20.1%, with 1, 2, 3, and >3 risk factors, respectively) and 21.0% secondary prevention patients. Applying AFSSAPS guidelines, the proportions of primary prevention patients not at LDL-cholesterol objectives varied across risk categories (P < 0.0001), from 3.9% for patients with one risk factor to 46.5% for patients with >3 risk factors, and therapeutic failure reached 39.9% in secondary prevention. Only 26% of patients who were at high cardiovascular risk (>3 risk factors or prior coronary heart disease) and not at therapeutic objective received high doses (>standard recommended doses) of lipid-lowering agents in monotherapy. Applying ANDEM guidelines, 74% of secondary prevention patients were not at treatment goal. CONCLUSION: Compliance with guidelines varied inversely with the level of cardiovascular risk. Besides, most patients not at therapeutic objective were not up-titrated. The use of lipid-lowering agents is inadequate, depriving many patients of an effective protection against cardiovascular diseases.

Adult↗
PubMed2003

[Subdural haemorrhage following lumbar spinal drainage during repair of thoraco-abdominal aneurysm].

Physicians in charge of patients undergoing thoracic or thoraco-abdominal aneurysmectomy, frequently use lumbar spinal drainage of the cerebrospinal fluid (CSF) to prevent paraplegia. Whereas the profit of this technique is a much debated question, we report 2 case reports of delayed sub-dural hemorrhage, after lumbar spinal drainage of CSF. Cross clamping of the aorta decreases the spinal cord artery pressure, increases the cerebral pressure and by alterations of distribution of the venous return, is responsible for an increase of the CSF pressure. This increase of the CSF pressure decreases the spinal cord driving pressure. Lumbar spinal drainage of CSF aims to improve the spinal cord driving pressure close to the normal (where driving pressure = aortic pressure - CSF pressure). The two case reports have to be added to the liability of a method of prevention that, as attractive that it is, did not give the proof of its efficiency to decrease the frequency and/or the severity of paraplegia after thoracic or thoraco-abdominal aneurysmectomy. At this time, this technique should be reserved to the patients with documented risk, as it is possible using preoperative spinal cord arteriography. The insertion and the withdrawal of the catheter must be done in the usual conditions of medullar puncture with regard to anticoagulant and antiplatelet agents

Aged↗
PubMed2003

[Regionalization of very preterm birth care sites in Ile-de France in 1998].

The objective of this article is to describe the conditions under which very premature babies were born in the Paris region between June 1 and December 31, 1998, that is to say those born prior to reaching 33 weeks of term (SA) and/or having a birth weight less than 1500 grams. The study looked at all pre-term births, including medical terminations of pregnancy (TOP), occurring in one of the 135 maternity units in the Paris region. Between June 1 and December 31, 1998, 1337 mothers gave birth to babies prior to reaching 33 weeks of term (SA) and/or having a birth weight less than 1500 grams in 84 maternity units in the Paris region, 263 of which had a medical termination of pregnancy (20%). These mothers were older than average for the region (25% were 35 years old or older); 4.3% of them do not have social insurance coverage. The remaining 1074 mothers (excluding TOP) gave birth to 1290 children, of which 202 were stillbirths, 46 died in the labor ward and 1042 were admitted to a neo-natal unit. Of the same group of 1074 mothers, 195 (18%) had a multiple pregnancy--175 twins, 19 triplets, and 1 quadruplet 60% of them (599 women) who had very premature or low birth weight babies (excluding TOPs) delivered them in a tertiary perinatal centre (TPC). This proportion varies according to two variables: 1) the community in which the family lives (40% in the Seine-et-Marne department, the eastern region of Paris and a district without TPCs, to 70% in the Hauts-de-Seine, a northern district), and 2) whether the pregnancy is single (58.8%), twin (72.6%) or triple (84.2%). In utero transfer accounts for 62.7% of the mothers who delivered in TPC, who were transferred prior to delivery. This type of study is useful for measuring the implementation of the regionalisation high-risk perinatal care and access to adequate services. It clearly demonstrates that inequities in access to care exist for women by district of residence.

Adult↗
PubMed2002

Migraine and the risk of cervical artery dissection: a case-control study.

The association between migraine and cervical artery dissection (CAD) was explored in a hospital-based case-control study. Migraine was present in 49.1% (23/47) of patients with CAD and in 21% (11/52) of patients hospitalized for a cerebral ischemic event not related to a CAD (adjusted odds ratio = 3.6; 1.5 to 8.6, p = 0.005). This result supports the hypothesis that an underlying arterial wall disease could be a predisposing condition for migraine.

Adult↗
PubMed2002

Characterization and regulation of a CHO cell line stably expressing human serotonin N-acetyltransferase (EC 2.3.1.87).

Current melatonin research is essentially based on the finding of new molecular tools, including synthetic or natural agonists and antagonists for the melatonin receptors and synthetic inhibitors of the enzymes involved in its biosynthesis. Indeed, the use of these compounds will improve our understanding of some of the numerous mechanisms of action of melatonin. The present report deals with the establishment and description of a new cell line expressing in a stable manner human arylalkylamine-N-acetyltransferase (AANAT, E.C.2.3.1.87). This new cellular system permits one to check the capacity of newly discovered inhibitors to penetrate the cell and reach their target. Some emphasis is put on inhibitors of the bromoacetyltryptamine family since these precursor compounds form in situ bisubstrate inhibitors with strong affinity for the human enzyme. AANAT is known to undergo complex and rapid regulation by a subtle balance between extremely fast catabolism and protection against it, both due to serine phosphorylation. In the present report, this phosphorylation is shown to occur in vitro after incubation with several kinases (rho-kinase, chk-1, protein kinase A) but not with protein kinase C. Phosphorylation enhances the specific activity of the enzyme by a factor of two to five. This phosphorylation is also shown to occur after treatment of the cell with compounds such as forskolin and rolipram that enhance or protect the intracellular pool of cAMP or the cell-permeable cAMP analogue, dioctanoyl-cAMP. The specificity of the cellular model was assessed using a series of substrates and inhibitors of AANAT already described in the literature, and the characteristics of this cellular system are shown to correspond with those reported for the purified enzyme. This cell line was used to screen libraries of compounds in a living system and led to the discovery of several potent specific and non-toxic AANAT inhibitors.

5-Methoxytryptamine↗
PubMed2002

The 5A6A polymorphism in the promoter of the stromelysin-1 (MMP3) gene as a risk factor for restenosis.

AIMS: Intracoronary ultrasound studies in humans show that chronic remodelling rather than neointimal hyperplasia is the mechanism of restenosis. Stent implantation limits this remodelling process and significantly reduces restenosis. MMP3 (Stromelysin-1), a member of the matrix metalloproteinase family may play a role in this remodelling. We used a functional polymorphism (with alleles designated 5A or 6A) in the promoter of the MMP3 gene to examine the possible role of MMP3 in restenosis. METHODS AND RESULTS: Genotypes were determined in a series of consecutive patients who underwent conventional balloon coronary angioplasty without stenting (n=287) or who also had successful implantation of a Palmaz-Schatz stent (stent) (n=198). For all patients restenosis was estimated at 6 months using quantitative computer-assisted angiography. The minimal luminal diameters before and after the procedures did not differ significantly between genotypes. At follow-up in the patients without stent, those with the 6A6A genotype had an increased degree of restenosis after coronary angioplasty compared to those with one or more 5A alleles, with a greater diameter stenosis (52+/-21% vs 45+/-19%, P=0.012), and a greater late loss (0.58+/-0.59 mm vs 0.38+/-0.59 mm, P=0.038). By contrast, in the stented patients MMP3 genotype was not associated with any angiographically determined measure of vessel dimensions. CONCLUSIONS: These data imply the involvement of MMP3 in chronic remodelling after conventional balloon angioplasty, and suggest that the 6A6A MMP3 genotype is a genetic susceptibility factor for restenosis after angioplasty without stenting.

Aged↗
PubMed2002

[Four-bone fusion of the wrist: review of 17 cases at an average 3.4 years follow-up].

PURPOSE OF THE STUDY: We reviewed retrospectively outcome after intracarpal arthrodesis for advanced-stage osteoarthritis of the wrist. MATERIAL AND METHODS: Among the 20 patients who underwent a four-bone fusion between 1989 and 1998 in our unit, 17 were available for analysis. Mean age of the study population was 41.5 years. These young patients had an occupational activity and 80% of them were manual laborers. Preoperatively, pain was the main complaint; 95% of the patients considered pain to be invalidating. Grip force was 48.5% compared to the healthy side. Joint amplitudes were limited in all patients: flexion-extension 85 degrees, radio-ulnar inclination 22.5 degrees with 12.5 degrees for the ulnar side. Mean loss of motion compared with the healthy side was 32.5% for flexion-extension, and 44% for radio-ulnar inclination. The preoperartive radiograph showed degenerated capito-lunate joints in 63% of the cases, degenerative scapho-capital joints in 58% and total loss of the radio-scaphoid joint space in 100%. Degeneration was considered to be global in 58% of the wrists. RESULTS: Mean follow-up for the 17 wrists studied was 3.4 years (range 1-10). At last follow-up, 41% of the wrists were pain free, 24% were painful occasionally, and 35% were bothersome for heavy work. The patients did not express any difficulties in daily activities. Grip force was only slightly improved with a 7.5% gain over the preoperative value. Joint motion at last follow-up was, on the average, 70 degrees flexion-extension (40 degrees flexion and 30 degrees extension) and 35 degrees radio-ulnar inclination (17.5 degrees ulnar). Eleven patients (65%) had resumed their occupational activities at the same level two months after surgery. Outcome was deemed satisfactory by 65% of the patients, fair by 17.5%, and poor by 17.5% (3 patients). Radiological fusion was achieved in 16 wrists at a mean 4.5 weeks. Mean carpal height was 0.42 compared with 0.52 for the healthy side and 0.47 preoperatively. There was no significant relationship between carpal height and poor outcome. DISCUSSION: Data in the literature are in agreement with the good results obtained for pain and activity level despite the inconstant effect on grip force and joint amplitude. CONCLUSION: Four-bone fusion is an effective treatment for patients with advanced-stage osteoarthritis of the wrist where the level of degeneration rules out resection. The consequences of total wrist arthroplasty are much more invalidating.

Adult↗
PubMed2001

Cadmium inhibits epoxidation of diatoxanthin to diadinoxanthin in the xanthophyll cycle of the marine diatom Phaeodactylum tricornutum.

Cd has pleiotropic effects on plant physiology and in particular on photosynthesis. It has not been established yet if Cd alters the functioning of the xanthophyll cycle. To answer this question, an exponentially growing culture of the marine diatom Phaeodactylum tricornutum was incubated with Cd (20 mg/l) for 24 h and irradiated with a light activating the xanthophyll cycle, which in diatoms, consists of the reversible deepoxidation of diadinoxanthin to diatoxanthin. The measurements show that the deepoxidation step is not influenced by Cd. In contrast, the Cd concentration used sharply inhibits the epoxidation of diatoxanthin to diadinoxanthin.

Cadmium↗
PubMed2001

Acute coronary syndrome without ST elevation: implementation of new guidelines.

Unstable angina and non-ST-segment-elevation myocardial infarction have in recent years been recognised as frequent and important clinical manifestations of coronary-artery disease. The European (ESC) and American (ACC/AHA) professional societies last year released guidelines on diagnosis, risk stratification, and treatment of these disorders. These guidelines summarise similarly the current evidence and translate them to clinical practice. Most important changes relate to the inclusion of troponins into the risk stratification algorithm, the addition of low-molecular-weight heparin and glycoprotein IIb/IIIa antagonists to medical treatment, and the role of invasive management for improved long-term outcome. Guidelines are constantly challenged by newly emerging study results. Recently, early invasive management and clopidogrel have been found to exert further benefit to this high-risk group of patients. Accordingly, the societies on both sides of the Atlantic will work together closely to update and implement these guidelines.

Abciximab↗
PubMed2001

An overview of the MAGE gene family with the identification of all human members of the family.

The first human members of the MAGE gene family that have been described are expressed in tumor cells but silent in normal adult tissues except in the male germ line. Hence, they encode strictly tumor-specific antigens that represent attractive targets for cancer immunotherapy. However, other members of the family were recently found to be expressed in normal cells, indicating that the family is larger and more disparate than initially expected. We therefore performed a database screening to identify all of the recorded members of both classes of human MAGE genes. This report provides an overview of the MAGE family and proposes a general nomenclature for all of the MAGE genes identified thus far. We found that the MAGE-D genes were particularly well conserved between man and mouse, suggesting that they exert important functions. In addition, the genomic structure of the MAGE-D genes indicates that one of them corresponds to the founder member of the family, and that all of the other MAGE genes are retrogenes derived from that common ancestral gene. Intriguingly, the COOH-terminal domain of MAGE-D3 was found to be identical to trophinin, a previously described protein believed to be involved in embryo implantation.

Amino Acid Sequence↗
PubMed2001

[Procalcitonin in pyelonephritis and acute community-acquired pneumonia in adults].

OBJECTIVES: Procalcitonin (PCT) is an acute-phase protein involved in the specific inflammatory reaction to severe bacterial or fungal infections. This protein does however lack sensitivity in focal infections. PATIENTS AND METHODS: In this study, we investigated PCT, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), leukocytosis, and fibrinogen levels at admission among adult patients hospitalized for community-acquired pneumonia (n = 33) or pyelonephritis (n = 30) and in a control population (n = 27) of patients with viral infections and non-infectious inflammatory diseases. RESULTS: Median serum PCT in the control group (0.21 ng/ml) was significantly lower than in the pyelonephritis group (0.46 ng/ml, p < 0.0005) or the pneumonia group (0.88 ng/ml, p < 0.0005). In the control group, median CRP was 51.4 ng/l reaching 220 mg/l in the pyelonephritis and 198 mg/l in the pneumonia group (p < 0.0005 in both cases). The other markers of inflammation investigated (leukocytosis, ESR, fibrinogen) did not show such differences between the control group and the sepsis groups. The sensitivity of PCT (threshold 0.5 ng/ml) was 61% for the diagnosis of pneumonia and 44% for the diagnosis of pyelonephritis. Specificity was 92% in both cases. In comparison, the sensitivity of CRP (threshold 50 mg/l) was 94% and 91% for pyelonephritis and pneumonia respectively with a 33% specificity in both cases. CONCLUSION: PCT is a specific but poorly sensitive marker of community-acquired pneumonia and pyelonephritis among adults hospitalized in medical wards.

Adult↗
PubMed2001

Comparison of two platelet glycoprotein IIb/IIIa inhibitors, tirofiban and abciximab, for the prevention of ischemic events with percutaneous coronary revascularization.

BACKGROUND: In the setting of percutaneous coronary revascularization, agents in the class known as platelet glycoprotein IIb/IIIa inhibitors have significantly reduced the incidence of death or nonfatal myocardial infarction at 30 days. We assessed whether there are differences in safety or efficacy between two such inhibitors, tirofiban and abciximab. METHODS: Using a double-blind, double-dummy design at 149 hospitals in 18 countries, we randomly assigned patients to receive either tirofiban or abciximab before undergoing percutaneous coronary revascularization with the intent to perform stenting. The primary end point was a composite of death, nonfatal myocardial infarction, or urgent target-vessel revascularization at 30 days. The trial was designed and statistically powered to demonstrate the noninferiority of tirofiban as compared with abciximab. RESULTS: The primary end point occurred more frequently among the 2398 patients in the tirofiban group than among the 2411 patients in the abciximab group (7.6 percent vs. 6.0 percent; hazard ratio, 1.26; one-sided 95 percent confidence interval of 1.51, demonstrating lack of equivalence, and two-sided 95 percent confidence interval of 1.01 to 1.57, demonstrating the superiority of abciximab over tirofiban; P=0.038). The magnitude and the direction of the effect were similar for each component of the composite end point (hazard ratio for death, 1.21; hazard ratio for myocardial infarction, 1.27; and hazard ratio for urgent target-vessel revascularization, 1.26), and the difference in the incidence of myocardial infarction between the tirofiban group and the abciximab group was significant (6.9 percent and 5.4 percent, respectively; P=0.04). The relative benefit of abciximab was consistent regardless of age, sex, the presence or absence of diabetes, or the presence or absence of pretreatment with clopidogrel. There were no significant differences in the rates of major bleeding complications or transfusions, but tirofiban was associated with a lower rate of minor bleeding episodes and thrombocytopenia. CONCLUSIONS: Although the trial was intended to assess the noninferiority of tirofiban as compared with abciximab, the findings demonstrated that tirofiban offered less protection from major ischemic events than did abciximab.

Abciximab↗
PubMed2001

The oxygenation variations related to prone positioning during mechanical ventilation: a clinical comparison between ARDS and non-ARDS hypoxemic patients.

OBJECTIVES: To compare, in clinical practice, the oxygenation variations related to prone positioning (PP) during mechanical ventilation in ARDS and non-ARDS hypoxemic patients. DESIGN AND SETTING: Prospective observational study of data on consecutive patients treated with the same protocol in the intensive care unit (ICU) of a university hospital. PATIENTS: From May 1996 to December 1998, 226 PP periods without adjunction of nitric oxide (NO) inhalation and/or almitrine bismesylate infusion, performed in 59 mechanically ventilated hypoxemic patients (arterial oxygen tension/fractional inspired oxygen (PaO2/FIO2) ratio <300 mmHg) with no evidence of left ventricular failure, were included in this study. MEASUREMENTS: Arterial blood gas was measured before the PP, at 1 h from the beginning of the PP, at the end of the PP and 1 h after returning to the supine position. RESULTS: We analyzed 136 PP periods in 34 non-ARDS patients (60.2%) and 90 in 25 ARDS patients. The PP was repeated and the duration of the PP periods was: 10.6+/-0.22 h. The PP during the mechanical ventilation appeared to be safe and well tolerated. A PaO2/FIO2 ratio improvement at the end of the PP period, occurred for 196 periods (86.7%) with a mean PaO2/FIO2 ratio increase of +46.4+/-0.03% at the end of the PP periods compared to the baseline supine value. The PaO2/FIO2 ratio variations at 1 h after the start of the PP, at the end of the PP period and at 1 h after the return to supine were not different in ARDS or non-ARDS hypoxemic patients. The PaO2/FIO2 ratio improvement appeared to be more intense and more rapid in ARDS patients. CONCLUSIONS: In about 90% of periods, PP improved the PaO2/FIO2 ratio in patients with ARDS as well as in hypoxemic patients with non-ARDS. Studies are necessary to determine the impact of PP on survival and the mechanical ventilation duration in ARDS or non-ARDS hypoxemic patients.

Analysis of Variance↗