[Is the coronary artery disease in woman so different from the man]. / La maladie coronaire chez la femme est-elle si différente de celle de l'homme?

Clinical presentation and symptoms of coronary artery disease may vary according to gender. This is not true to the same extent for acute coronary syndromes. The diagnosis is more complex in women because they show less often a typical clinical picture. In spite of these gender-related clinical differences, no diagnostic strategy in the detection of the coronary artery disease is recommended for women. Because "standard" treadmill or bicycle ECG stress test has a low specificity in women, non-invasive imaging (stress echocardiography, myocardial scintigraphy or cardiac magnetic resonance) should be preferred for the evaluation of myocardial ischemia in women.

[Do we have to be scared of chronic constitutional low blood pressure]. / Faut-il avoir peur de la pression artérietlle chronique constitutionnelle basse?

Chronic constitutional low blood pressure entity has been poorly studied. Typically, affects quality of life, because of manifold symptoms. Its mechanisms are not well understood but diminished cerebral blood flow, microcirculation and autonomic deregulation have been documented. Its' treatment is disappointing, without any demonstrated improvement of symptoms or prognosis. Thus, a complete medical examination is needed to exclude any organic cause. If none is found, it is important to reassure the patient and to convince him not to use expensive drugs potentially generative of side effects.

[Stress echocardiography: it is all in the contrast!]. / Echocardiographie de stress: tout est une question de contraste!

The availability of myocardial contrast echocardiography has potential for several applications in coronary disease. Experimental studies have demonstrated a good correlation between measurements of myocardial blood flow and regional contrast intensity, and therefore capabilities of myocardial contrast echocardiography in detecting myocardial ischemia during stress. Recently, clinical studies have confirmed the value of this new technique in comparison with radionuclide imaging.

[Resistant hypertension]. / Hypertension artérielle résistante: quo vadis?

Hypertension is a cardiovascular risk factor which needs a good evaluation before treatment. When this latter is decided, the target is to normalize high blood pressure. This requires a complete information of the patient; the latter will also receive individualized non pharmacological advices and also possibly different antihypertensive drugs. When blood pressure does not normalize, one must check the pressure measurement technique, the compliance to treatment and potential pharmacological interferences. Secondary hypertension is only considered if resistance to therapy cannot be found. It should be remembered that obesity and sleep apnea disorders are responsible of many instances of resistant hypertension.

[Silent myocardial ischaemia: a deafening silence]. / L'ischémie myocardique sitencieuse: un silence assourdissant.

Angina pectoris, whether stable or unstable, is not the most common ischaemic manifestation of coronary heart disease. Silent or asymptomatic ischaemia is the most frequently encountered ischaemic event in coronary heart disease. nevertheless, its prevalence is very variable, depending on the studied population (2-4% in asymptomatic patients, 20-30% after an myocardial infarction, 40-60% in stable angina and 60-80% in unstable angina). In this context, silent ischaemia raises many questions with regards to the rational use of diagnostic tools (stress test, holter electrocardiographic recording and stress imaging tests), their prognostic interpretation and its management.

Unusual presentation of a left ventricular aneurysm.

We report on a case of left ventricular aneurysm in a 42-year-old woman presenting with atypical chest pains. The resting electrocardiogram showed abnormal Q and T negative waves in leads II, III, and aVF. Transthoracic echocardiography revealed an aneurysm on the posterior wall of the left ventricle. Thallium myocardial tomoscintigraphy confirmed the presence of a persistent defect with uneven uptake in the posterior wall, and coronary arteriography showed perfectly normal coronary arteries. A left ventricular aneurysm associated with normal coronary arteries and transient ischemia was diagnosed following a comparison with one of the patient's old electrocardiograms.

Alpha-tocopherol controls cell proliferation in the adult rat dentate gyrus.

The effect of alpha-tocopherol on cell proliferation and proliferated cell survival was investigated in the dentate gyrus of adult rats. Adult rats were supplemented with alpha-tocopherol, injected with 5-bromo-2'-deoxyuridine (BrdU), that is incorporated into DNA during the S-phase, and killed at different time after BrdU injection. The number of newborn cells decreased after alpha-tocopherol supplementation, confirming the hypothesis that alpha-tocopherol is able to depress cell proliferation in vivo. Most newborn cells die within few days; more newborn cells survive in alpha-tocopherol-treated rats, suggesting the hypothesis that alpha-tocopherol decreases cell death.

Diagnosis of coronary artery disease in patients with permanent cardiac pacemaker by dobutamine stress echocardiography or exercise thallium-201 myocardial tomography.

This study evaluated the use of dobutamine stress echocardiography and exercise thallium-201 myocardial computed tomography (CT) in the diagnosis of coronary artery disease (CAD) in patients with permanent transvenous pacemaker with the electrode implanted in the right ventricle (RV). Twenty-nine consecutive patients with pacemaker underwent dobutamine stress echocardiography, exercise thallium-201 myocardial CT, and coronary arteriography over a period of 8 +/- 1 days. None of these patients had suffered a myocardial infarction (MI). The cardiac rhythm of every patient was electrically paced during echocardiography and tomography. Sixteen (55%) patients showed CAD on angiography (stenosis > or = 50% of the luminal diameter of a major epicardial vessel). The detection sensitivity for CAD was 94% for the tomography and 88% for the echocardiography (P = NS). The difference between the sensitivities of the two techniques in detecting CAD based on the affected coronary artery was not statistically significant. Of the 13 patients without CAD, tomography showed a positive result in nine cases, i.e., a specificity of 31%, whereas echocardiography showed a positive result in only one case, i.e., a specificity of 92% (P < 0. 01). Exercise thallium-201 myocardial computed tomography produces an increased rate of false-positive results in patients with permanent transvenous cardiac pacemaker (PCP) implanted in the right ventricle (RV). Dobutamine stress echocardiography can thus be used to reduce considerably the level of false-positive results in these patients and still retain a detection sensitivity for CAD equal to that of myocardial tomography.

Spatial learning affects immature granule cell survival in adult rat dentate gyrus.

Neurogenesis occurs throughout life in mammalian dentate gyrus. The effect of learning on newborn cell survival was studied in rat. Rats were trained on a hippocampus-dependent spatial learning task by using Morris water maze. Neurogenesis was evaluated by 5-bromo-2'deoxyuridine administered before learning. Several newborn cells expressed the immature neuron marker TOAD-64. The main findings were as follows: (1) the survival of newborn cells was enhanced by learning at early stage of differentiation; (2) the newborn cells saved by learning were mainly located in the rostral part of external blade of granule cell layer and (3) there was a correlation between the actual individual learning and newborn cell survival.

Clinical study to investigate the predictive parameters for the onset of atrial fibrillation in patients with essential hypertension.

BACKGROUND: The risk factors involved in the onset of atrial fibrillation (AF) are well known, but the predictive clinical and paraclinical parameters for the onset of AF in hypertensive patients have not been investigated specifically. METHODS AND RESULTS: We retrospectively analyzed 97 consecutive patients with hypertension and no known history of AF or cardiovascular events who attended the cardiology outpatient clinic. The analysis was based on clinical data, the noninvasive ambulatory 24-hour measurement of blood pressure (AMBP), a standard 12-lead electrocardiogram, and a Doppler echocardiogram. After a mean follow-up of 25 +/- 3 months, 19 (19. 5%) patients had AF, 3 (15.8%) of whom had a cerebrovascular accident. The patients with AF were older than the others and their AMBP showed higher mean systolic diurnal and nocturnal blood pressures, though no differences in the clinical blood pressure readings were present. On the electrocardiogram, the maximum duration of the P wave and its dispersion were more prolonged in the patients with AF. On the Doppler echocardiogram, left ventricular mass and left atrial dimension were higher in the patients with AF, and the A-wave velocity of diastolic mitral flow was reduced in these patients. In the multivariate analysis, age (odds ratio 3.28, P <.001), diurnal systolic blood pressure (odds ratio 1.35, P <.01) and nocturnal systolic blood pressure (odds ratio 1.16, P <.01), maximum duration of the P wave (odds ratio 2.09, P <.01), dispersion of the P wave (odds ratio 2.52, P <.001), echocardiographic left ventricular mass (odds ratio 1.43, P <.01), left atrial dimension (odds ratio 2.81, P <.001), and velocity of the A wave (odds ratio 2. 24, P <.01) were independent predictors for the onset of AF. After correction for age, maximum duration of the P wave (odds ratio 1.34, P <.01), dispersion of the P wave (odds ratio 1.63, P <.001), and the velocity of the A wave (odds ratio 1.42, P <.01) remained independent predictors for the onset of AF. CONCLUSIONS: In patients with hypertension, age and the level of diurnal and nocturnal systolic blood pressures measured by 24-hour AMBP are important independent predictors for the onset of AF. Independent of age, increases in left atrial dimension and left ventricular mass, prolongation of the maximum duration and dispersion of the P wave and reduced A-wave velocity are also predictors for the onset of AF.

Are there proliferating neuronal precursors in adult rat dorsal root ganglia?

The origin of new neurons in dorsal root ganglia of adult rat was investigated using an experimental model in which postnatal neurogenesis naturally occurring is enhanced and restricted in a brief period of life. Possible mitotic origin of new neurons was investigated by means of 5-bromo-2-deoxyuridine, anti-NF 200 antibody was used to detect if proliferated cells showed a neuronal phenotype. The results suggest that postnatal neurogenesis in dorsal root ganglia could depend only in part on precursor proliferation and that normally new neurons derive from the late differentiation of postmitotic cells.

Postnatal proliferation of DRG non-neuronal cells in vitamin E-deficient rats.

Changes in the number of satellite cells in neuron body sheaths in dorsal root ganglia (DRGs) were studied from 1 to 5 months of age in control and in vitamin E-deficient rats; furthermore, the satellite cell proliferation rate was detected in the same groups of animals with immunohistochemistry for 5-bromo-2'-deoxyuridine (BrdU). The number of satellite cells in sheaths of DRG neurons increased in the period of life considered both in control and in vitamin E-deficient rats. Satellite cell proliferation was observed in both groups, but its rate was found to be higher in vitamin E-deficient rats. The results obtained in control rats confirm that mitotic ability is retained by satellite cells in adulthood and show that at least some of newborn satellite cells add to the pre-existing population. The results obtained in vitamin E-deficient rats suggest that a faster turnover in satellite cell population takes place in these animals and support the idea that vitamin E could be an exogenous factor controlling cell proliferation.

Neurogenesis in the adult rat dentate gyrus is enhanced by vitamin E deficiency.

Neurogenesis occurs throughout adult life in rat dentate gyrus. Factors and mechanisms of adult neurogenesis regulation are not well known. Vitamin E deficiency has been found to deliver a neurogenetic potential in rat dorsal root ganglia. To determine whether the role of tocopherols in adult neurogenesis may be generalized to the central nervous system, changes in adult rat dentate gyrus neurogenesis were investigated in vitamin E deficiency. Neurogenesis was quantitatively studied by determination of the density of 5-bromo-2'-deoxyuridine (BrdU)-labeled cells and by determination of the total number of cells in the granule cell layer. The BrdU-labeled cells were immunocytochemically characterized by demonstration of neuronal marker calbindin D28K. The following results were found: (1) the volume of the granule layer increased in controls from 1 to 5 months of age, mainly due to cell density decrease; (2) the volume increased by a similar amount in vitamin E-deficient rats, mainly because of an increase in cell number; (3) BrdU-positive cells were more numerous in vitamin E-deficient rats in comparison to age-matched controls; (4) the increase in proliferated cells was located in the hilus and in the plexiform layer. This study confirms that neurogenesis occurs within adult dentate gyrus and demonstrates that this process is enhanced in vitamin E deficiency. This finding indicates that vitamin E may be an exogenous factor regulating adult neurogenesis.

Neuron and glial cells in neocortex after methylazoxymethanol treatment in early development.

The quantitative changes were investigated in neuron and glia density in the different cortical layers of the frontal cortex of 3 and 12 month old mice, exposed to methylazoxymethanol on embryonic day 13 (MAM13). No loss of cortical neurons was found between young and adult animals. MAM exposure on the 13th day of development induced a neuron density decrease throughout on the entire cortical depth and did not produce changes in the density of glial cells with respect to the controls and to age. Consequently, at 3 months of age we observe a glia/neuron ratio greater than that of controls and at 12 months a similar value. In the neocortex of MAM-mice at this numerical uniformity of glial cell density, did not correspond to a similar proportional composition: the frequency of the astrocytes is lower, adapting to the decreased neuron density; the greater oligodendrocyte percentage may be related to disturbed layering and to the hyperinnervation of the hypoplastic cortex; the microglia shows a trend similar to that of the controls. These results, together with those of other studies, suggest that prenatal exposure to MAM causes a cortical compensatory response regulating glial cells proliferation.

[Clinical value of measuring systolic arterial blood pressure post-exercise for evaluation and diagnosis of coronary disease: comparative study between women and men]. / Intérêt clinique de la mesure de la pression artérielle systolique dans le post-effort pour l'évaluation et le diagnostic de la maladie coronarienne: étude comparative entre femmes et hommes.

It has been demonstrated that the ratio of the systolic blood pressure post-exercise to that at peak exercise (rSBP) is a criterion for diagnosis and severity of coronary artery disease (CAD) in men. No such demonstration has been attempted in women. We have compared SBP to classical signs of ischemia, such as ST segment depression and angina pectoris, in a group of 788 ambulatory patients of whom 357 were women. All underwent a bicycle ergometric test and a coronary angiogram. The prevalence of CAD at angiography was the same for both genders (women 43.5% and men 47%) with no significant difference in the number of vessels diseased. In patients with CAD, the rSBP was significantly more elevated than in others, at 1 minute (p < 0.01) and even more so at 3 minutes (p < 0.001) post-exercise, with no gender difference. The most discriminating value of rSBP at 3 minutes post-exercise for diagnosis of CAD was situated at 0.91 for sensitivity and specificity (receiver operating characteristic curve analysis). In the whole group sensitivity of rSBP is lower, while the specificity is greater than classical criteria of ischemia. The sensitivity of rSBP is poor for the diagnosis of single vessel disease, but of equal value compared to ST segment depression in the presence of multivessel disease, with no gender difference. The specificity of rSBP is higher than ST segment depression in women (p < 0.001) compared to men (p < 0.05). rSBP has a positive correlation with the number of coronary vessels diseased but not with the extent of ST segment depression. Our study demonstrates that rSBP at 3 minutes post-exercise is a less good diagnostic sign than the classical criteria of myocardial ischemia. However, rSBP has good specificity, particularly in women, thus reducing false positive tests related to ST segment depression. rSBP is also a marker of the severity of coronary artery disease.

Vitamin E affects quantitative age changes in lumbar motoneurons and in their peripheral projections.

Vitamin E deficiency was previously found to induce plastic changes in the number of primary sensory neurons and in motoneuron peripheral field projections. In this work, quantitative changes in motoneurons of lumbar segments, in nerve fibres constituting ventral roots and in innervating leg motor fibres were studied in normal and vitamin E deficient rats from 1 to 5 months of age. The number of lumbar motoneurons was found to decrease, while there were no changes in the number of ventral root fibres. An increase in the number of innervating leg motor fibres was observed during ageing in control rats; in vitamin E deficient rats the number of fibres in the ventral roots did not change, as occurred in controls, but the decrease in the number of motoneurons was smaller and the number of innervating leg motor fibres increased further in comparison to the controls. The findings are consistent with the idea that vitamin E deficiency causes a decrease in motoneuron death or, alternatively, that it induces some process partially compensating naturally occurring motoneuron death.

Quantitative changes in neuron and glial cells of neocortex following prenatal exposure to methylazoxymethanol.

The quantitative changes in neuron and glial cell density were analyzed in different cortical layers from frontal cortex of 3 and 12 months old mice exposed to Methylazoxymethanol (MAM) on embryonic day 15 (MAM 15) or 17 (MAM 17). An increase was found in glial cell density in all cortical layers from 3 months old MAM 17 compared to the age-matched controls. In particular, electron microscopic analysis showed that the only cells to increase in all cortical layers were the microglia cells. When the young and adult mice were compared it was noted that the glia increased significantly in all cortical layers of controls, whereas it did not change the older MAM 17. In the older MAM 15 the increase in glial density was similar to that observed in controls. No loss of cortical neurons was found between young and adult animals. In addition, the different trend of glial cell density between control and MAM 17 mice during aging was accompanied by a decline in the mean nuclear area in neurons of treated mice with respect to the controls. The hypothesis that MAM treatment seems to produce events similar to those normally occurring in aging finds support in the data of glial density and neuron size.

Motor nerve sprouting induction by a nerve explant in normal and vitamin E-deficient rats.

Sprouting induction by a peripheral degenerating nerve has been evaluated in normal and vitamin E-deficient rats. A piece of sural nerve was grafted close to the peroneal nerve of the same animal: at one and two months after grafting thin unmyelinated axons were visible in the graft and they were sometimes functionally active; when nerve explant was frozen before grafting, sprouting induction did not take place either in controls or in vitamin E-deficient animals. No difference was noted in sprouting induction between the two groups, while degeneration showed a different time course. Some hypotheses of possible stimuli of sprouting induction are discussed.