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Biomedical subjects

C Henry

Publications and source records attributed to C Henry.

At least 73 records · Page 4Linked to original sources
PubMed1997

Preliminary clinical experience with the first dual chamber pacemaker defibrillator.

The lack of specificity of VT detection is a significant shortcoming of current ICDs. In a French multicenter study, 18 patients underwent implantation of the Defender 9001 (ELA Medical), an ICD utilizing dual chamber pacing and arrhythmia detection. Over a mean follow-up period of 7.1 +/- 4.5 months, 176 tachycardia episodes recorded in the device memory were analyzed, and physician diagnosis was compared with that by the device. All 122 VT/VF episodes were correctly diagnosed, as were 51 of 53 supraventricular tachyarrhythmias. Two episodes of AF with rapid regular ventricular rates were treated as VT, and a third episode, treated as VT, could not be diagnosed with certainty. A dual chamber pacemaker defibrillator offers improved diagnostic specificity without loss of sensitivity, in addition to the hemodynamic benefit of dual chamber pacing.

Adolescent↗
PubMed1997

Is bronchial hyperresponsiveness more frequent in women than in men? A population-based study.

To test the hypothesis that a greater proportion of women than men react to methacholine challenge and investigate the possible reasons for any differences observed, we recruited 495 subjects 20 to 44 yr of age (50.9% male) in Paris and 304 subjects (51.3% male) in Montpellier (France), as part of the European Community Respiratory Health Survey. The proportion of responders (PD20 < or = 4 mg methacholine) was 33.7% in women and 11.9% in men (odds ratio = 3.8; 95% confidence interval = 2.4-6.0) in Paris and 43.2% in women and 29.5% in men (odds ratio = 1.8; 95% confidence interval = 1.1-2.9) in Montpellier. These differences could not be explained by asthma, respiratory symptoms, atopy, or lung function parameters. In stepwise logistic regressions including sex, asthma, and asthma-like symptoms, nasal allergies, atopy, baseline FEV1, FEV1%pred, FVC, and FEV1%FVC, the odds-ratios for the effect of female sex on PD20 < or = 4 mg methacholine were 5.2 (3.0-9.0) in Paris and 2.2 (1.2-3.8) in Montpellier. Reacting to low doses of methacholine (PD20 < or = 0.5 mg) was associated with asthma and atopy in both men and women. In contrast, reacting to doses between 0.5 and 4 mg was associated with asthma and atopy only in men and with heavy tobacco consumption only in women. We conclude that the excess of hyperresponsiveness in women is not due to their having smaller lung size or airway caliber than men and may be related to a greater susceptibility to smoking.

Adult↗
PubMed1996

Transient neonatal elevation in hypothalamic estrogen receptor mRNA in prenatally-stressed male rats.

Prenatal stress in rats has been found to alter the sexual dimorphism of brain structures and the sexual behavior of male offspring, pointing to an impaired masculinization of the brain during the perinatal period of brain sexual differentiation. Masculinization of the brain depends on the presence during this critical period of three main elements: adequate levels of testosterone, aromatase activity (locally converting testosterone to estradiol), and brain estrogen receptor (ER) density. In the present study, we measured by reverse transcription-polymerase chain reaction (RT-PCR) the levels of ER messenger RNA (mRNA) expression in the hypothalamus of either prenatally-stressed or control male rats at postnatal (P) days 3, 12 and 90. During the early postnatal period (P3), hypothalamic ER mRNA expression was higher in prenatally stressed male rats (6.12 +/- 0.37) than in controls (4.51 +/- 0.55) (P = 0.015). This difference was not, however, found at a later developmental stage (P12, 5.39 +/- 0.65 versus 5.39 +/- 0.47) or in adult animals (P90, 6.79 +/- 1.55 versus 7.07 +/- 1.11). This transient elevation of hypothalamic ER mRNA expression resembles the developmental profile of ER mRNA in females. These observations support the idea that androgens play a pivotal role in the demasculinization process, and suggest that testosterone production or aromatization is reduced in prenatally-stressed males during the perinatal period of sexual differentiation, leading to a transient upregulation of unstimulated estrogen receptors.

Animals↗
PubMed1996

Postnatal ontogeny of dopamine D3 receptors in the mouse brain: autoradiographic evidence for a transient cortical expression.

The expression of dopamine D3 receptors is relatively low in the adult brain and is mainly restricted to the limbic region. We studied here the postnatal development of these receptors in the mouse brain by quantitative autoradiography using [3H](+/-)-7-OH-DPAT as ligand. In all brain regions examined, there was a progressive increase in D3 receptor protein expression from birth to the weaning period, a pattern reminiscent of that of dopamine D2 rather than D1 receptors. In broad outline, the regional distribution of D3 receptors during brain ontogeny resembled that observed in adult animals, the labelling being detected earlier in the structures with the higher density in the adult. The highest and earliest expression of D3 receptors was observed in the islands of Calleja and olfactory tubercle, where [3H]7-OH-DPAT binding was already present at birth. D3 receptors appeared at postnatal day 4 in the nucleus accumbens, at postnatal day 8 in the substantia nigra, in the medial mamillary nucleus and in the anterior thalamic complex, and at postnatal day 11 in the archaeocerebellum. In contrast to other brain structures where the developmental pattern of D3 receptor expression parallelled its distribution and density in the adult brain, there was a transient cortical expression of [3H]7-OH-DPAT binding between postnatal days 6 and 15, confined to a longitudinal strip in the dorso-lateral part of the parietal cortex. This expression had disappeared by postnatal day 21 and was not detected in adult mice. These developmental findings, and particularly the transient cortical expression of functional receptors, point to the involvement of D3 receptors in ontogenic processes.

Animals↗
PubMed1996

Adult bone marrow contains precursors for CD5+ B cells.

To determine directly whether B cell precursors of adult origin are capable of generating CD5+ B cells, we reconstituted neonatal C3H. SCID mice with adult C57BL/6 bone marrow and analyzed splenic B cells 10 months later. Surface staining and flow cytometry revealed that the B cells were of donor origin and that 30% were CD5+. This confirms that in vivo generated CD5+ B cells can be adult derived. After anti-IgM (but not lipopolysaccharide) stimulation in vitro, virtually all of the B cells from the bone marrow-reconstituted mice expressed surface CD5. Sequence analysis of expressed VHDJH genes from the CD5+ B cells present after anti-IgM stimulation revealed a high frequency of N nucleotide addition in CDR3 regions. The presence of N nucleotides indicates that these sequences were derived from CD5+ B cells of adult origin rather than from long-lived fetal precursor B cells present in either the adult bone marrow at the time of transfer or adult spleen. These experiments demonstrate conclusively that adult bone marrow contains precursors for CD5+ B cells and that unlike fetal liver-derived precursors these express terminal deoxynucleotidyl transferase.

Animals↗
PubMed1996

Biological studies of analogues of glucose iodinated in positions 1, 2, or 3.

Analogues of glucose labeled with 123 iodine in positions 1, 2 or 3 have been synthesized. The aim of this study was to examine their biological behavior in four experimental models in order to assess whether they could be used to evaluate the uptake of glucose with single photon emission computed tomography (SPECT). The results obtained have shown that none of these molecules enters the cell using the glucose transporter. Therefore, they cannot be used as tracers of glucose uptake.

Animals↗
PubMed1996

Undertreatment in a nonselected population of adult patients with asthma.

BACKGROUND AND AIM: The question of undertreatment has frequently been raised concerning the management of asthma but, to date, very few studies have been carried out. In those studies that have been performed, the methodology was inadequate because they were conducted on a selected population of patients with asthma or by interviewing doctors. As part of the European Community Respiratory Health Survey, nonselected patients with asthma (22 to 44 years old) in two French cities (Paris and Montpellier), were examined to assess possible undertreatment. METHODS: Patients with asthma were recruited according to a positive response to questions on asthma in a questionnaire and a positive methacholine challenge. The severity of asthma was assessed by a cumulative score, which has previously been shown to be significantly correlated with the validated clinical score of Aas. Patients were asked to attend the clinic and bring with them any medications that they regularly received. The optimal treatment of asthma was based on the International Consensus Report on the Management of Asthma. RESULTS: According to the international guidelines, among the patients who required antiinflammatory treatment, 86.4% were undertreated in Paris and 66.7% were undertreated in Montpellier (p < 0.03, chi square test). Moreover, among the patients with severe asthma, 85% and 60%, respectively, were not receiving an antiinflammatory treatment. CONCLUSION: This study is the first to highlight the magnitude of undertreatment of patients with asthma in a nonselected population.

Adult↗
PubMed1996

Initial end-tidal CO2 is markedly elevated during cardiopulmonary resuscitation after asphyxial cardiac arrest.

OBJECTIVES: To compare the initial end-tidal CO2 (PetCO2) during cardiopulmonary resuscitation in asphyxial versus ventricular fibrillatory cardiac arrest. DESIGN: A cohort study. SETTING: University research laboratory. SUBJECTS: Forty domestic piglets. INTERVENTIONS: Asphyxial cardiac arrest was produced by clamping the endotracheal tube in 20 piglets and was continued for 10 minutes after loss of aortic pulsations occurred. Ventricular fibrillation (VF) was induced by applying 60 Hz of alternating current via a pacing wire to the myocardium of the other 20 piglets, and continued for a 15-minute downtime. Cardiopulmonary resuscitation (CPR) was then provided to each group for two minutes, followed by standard advanced cardiac life support protocols. MEASUREMENTS AND MAIN RESULTS: All piglets were instrumented for continuous monitoring of PetCO2, electrocardiogram, central venous pressure, and aortic pressure. PetCO2 of the first breath of CPR was 91 +/- 20 mmHg in the asphyxial group versus 34 +/- 14 mmHg in the VF group (P < 0.001). The asphyxial group continued to exhibit significantly greater PetCO2 for the first five breaths of resuscitation, after which there were no differences. The coronary perfusion pressures during the first breaths of CPR did not differ between the two groups. High initial PetCO2 did not correlate with return of spontaneous circulation. CONCLUSIONS: End-tidal CO2 during the first five breaths of CPR is much higher after an asphyxial cardiac arrest than VF. In each case, the initial PetCO2 appears to reflect alveolar CO2 prior to CPR. After one minute of CPR, PetCO2 is useful in monitoring the effectiveness of CPR.

Animals↗
PubMed1996

Alcohol consumption, gamma-glutamyl transpeptidase (GGT), and pulmonary function: a cross-sectional and longitudinal study in working men.

Epidemiological studies of the relationships between pulmonary function and reported alcohol intake showed inconsistent results. The use of biological markers of alcohol is needed. The objective of this study was to assess the relationships of alcohol consumption, assessed by a standardized questionnaire, and gamma-glutamyl transpeptidase (GGT), to forced expiratory volume in 1 sec (FEV1) level and decline over 10 years, in working men. Three hundred twenty-eight policemen aged 22-55 years were examined in 1980 (first survey) and again in 1990 (second survey). The two cross-sectional analyses used the 1980 data and the 1990 data separately. Longitudinal analysis used 1980 alcohol consumption and GGT values, and 10-year FEV1 decline. In both cross-sectional surveys, elevated alcohol consumption was significantly associated with impaired age-adjusted and height-adjusted FEV1. Further adjustment for smoking habit, education level, and asthmatic status did not alter these results. An increase of 25 g/day of alcohol was associated with 50.0 ml (95% confidence interval: 1.5 to 98.5) and 55.3 ml (95% confidence interval: 7.8 to 102.8) decrease of corresponding multivariate-adjusted FEV1 in 1980 and in 1990, respectively. GGT was also negatively associated with FEV1 in both cross-sectional surveys. Similar patterns of associations were also observed between vital capacity measurements and alcohol variables. In the longitudinal analysis, there was no relationship between either alcohol consumption or GGT and FEV1 decline. Findings suggest that alcohol consumption was associated with impaired lung function, but there was no evidence of accelerated FEV1 decline over 10 years related to alcohol consumption in this "healthy" population of middle-aged men.

Age Factors↗
PubMed1996

[Mortality by respiratory disease in ten European and North American countries (1979-1990)].

The aim of this paper is to compare respiratory mortality, cancer and tuberculosis excluded, in 10 countries during 12 years. Mortality data came from World Health Statistics Annual of the WHO and age adjusted rates were calculated. For all causes respiratory mortality, acute pathologies and chronic obstructions not elsewhere classified, United Kingdom and above all Eire have the highest rates; Italy, France and Germany have the lowest rates; the other countries (Belgium, Denmark, Netherlands, Canada, United States) have rates similar, sometimes equal). For chronic conditions, Denmark has the highest rates, Canada and United States the lowest; Eire and United Kingdom begin a great decrease from 1983. On the whole, differences between countries do not vary very much with the years or the pathologies and the evolution over the time is not very marked apart from some countries.

Acute Disease↗
PubMed1995

Prenatal stress in rats facilitates amphetamine-induced sensitization and induces long-lasting changes in dopamine receptors in the nucleus accumbens.

Exposure of rats to restraint stress during late pregnancy produces offspring with a variety of behavioral and neurobiological alterations. It has been suggested that prenatal stress leads to long-lasting changes in the hypothalamo-pituitary-adrenal axis in the offspring. One feature of prenatally-stressed rats is a susceptibility to amphetamine self-administration. Since this behavior has been related to amphetamine-induced sensitization and the activity of the mesolimbic dopamine system, we measured dopamine receptor densities and amphetamine-induced sensitization in these animals. The motor response to the first administration of amphetamine was similar in both prestressed and unstressed groups of adult animals, but after repeated drug injections, behavioral sensitization was observed sooner in the prenatally-stressed rats than in the controls. In separate groups of adult animals, densities of D1, D2 and D3 dopamine receptor subtypes in the striatum and nucleus accumbens were measured in prenatally-stressed and control rats by quantitative autoradiography using [3H]SCH23390, [3H]sulpiride and [3H]7-OH-DPAT as ligands respectively. Prenatal stress was found to produce the following alterations in the adult offspring: (i) no significant change in D1 receptor binding in either striatum or nucleus accumbens; (ii) a significant (+24%) increase in D2 receptor binding in the nucleus accumbens; (iii) a significant decrease in D3 receptor binding in both the shell (-16%) and the core (-26%) of the nucleus accumbens. These observations indicate that prenatal stress induces long-lasting changes in the dopamine sensitivity of the nucleus accumbens and in the capacity to develop amphetamine-induced sensitization in adulthood. The possible relationship between an impaired control of corticosterone secretion in prenatally-stressed animals and long-term changes in the mesolimbic dopamine system is discussed.

Amphetamine↗
PubMed1995

Effects of ibogaine on sensory-motor function, activity, and spatial learning in rats.

Ibogaine, a naturally occurring alkaloid, has been show to reduce naloxone-precipitated withdrawal symptoms from morphine. Given the clinical possibilities, it is important to determine ibogaine's effects on sensory-motor function, activity, learning, and memory. Long-Evans rats injected with doses of 20-60 mg/kg of ibogaine displayed slower response times on sensory and sensory-motor tests and were impaired in performing specific motor reflexes at doses of 40-60 mg/kg. Furthermore, these rats showed a marked reduction in locomotor and nonlocomotor activity, as well as emotionality at doses ranging from 10-40 mg/kg. At the higher doses the rats appeared to be virtually inactive. There were also deficits in learning a spatial location task (a dry-land version of the Morris water-maze). The deficits, however, were probably due to a reduction in locomotor activity and reduction in detection of sensory information. In a final experiment, a single injection of 40 mg/kg of ibogaine had marked deleterious effects on the acquisition of the spatial location task 1 but not 7 days after the injection, even though in this case there were no effects on sensory motor function 1 or 7 days after the injection. Thus, there are severe sensory-motor activity and learning problems while the animal is under the influence of ibogaine (acute effect) as well as long-term consequences on learning without concomitant changes in sensory-motor function.

Animals↗
PubMed1995

[Spontaneous colonic perforations revealing Ehlers-Danlos syndrome type IV].

BACKGROUND: The malignant form of Ehlers-Danlos syndrome type IV owes its bad reputation to a proneness to spontaneous rupture of bowel or large vessels, which may reveal the disease. CASE REPORT: A girl suffered acute rupture of the sigmoid at the age of 5 years and rupture of the left colon, twice, at the age of 11 and 13 years, respectively. These ruptures required colostomy and finally colectomy. A proneness to bruisability, history of dislocation of hips, hypermobile joints, ovarian cysts and some minor abnormalities of her face resembled that of the Ehlers-Danlos syndrome which was confirmed by optic and electronic microscopy of the skin biopsy. CONCLUSION: This is the youngest case of rupture of bowel reported in Ehlers-Danlos syndrome. Long-term prognosis is influenced by repetition of intestinal ruptures and occurrence of vascular complications.

Child, Preschool↗
PubMed1995

Prevalence of asthma and asthma-like symptoms in three French cities.

BACKGROUND: This study is part of the European Community Respiratory Health Survey (ECRHS), which uses a common methodology in different areas throughout the world. This paper describes the prevalences of reported asthma, asthma-like symptoms and nasal allergies, their relationships to age group and sex, and the relationships of asthma-like symptoms to current asthma, in the general population aged 20-44 years of three French urban areas. METHODS: The study population of 2804 subjects in Grenoble, 3774 in Montpellier and 3152 in Paris (18th district), randomly selected from electoral rolls, answered a postal questionnaire (stage I of ECRHS). The response rates were 77.8%, 68.6% and 74.4%, respectively. RESULTS: The prevalences were approximately 14% for wheezing, 16% for chest tightness and 4.5% for nocturnal shortness of breath in the three areas. Asthma attacks in the last 12 months were reported by 2.7% of subjects in Grenoble, 3.5% of subjects in Montpellier and 4.0% of subjects in Paris (P = 0.02). For nasal allergies, the prevalences were 28.0%, 34.3% and 30.8%, respectively (P < 0.001). Asthma was inversely correlated to age (higher prevalence in the youngest) but was not related to sex. Neither age distribution nor sex ratio explained the differences between areas. Among the asthma-like symptoms, wheezing and nocturnal shortness of breath correlated strongly with asthma, chest tightness correlated moderately and nocturnal coughing correlated poorly. CONCLUSION: The prevalences observed were higher than expected from previous comparable French studies in young adults. These results are consistent with the hypothesis of a recent increase of asthma and allergies.

Adult↗
PubMed1995

Experimental models, protocols, and reference values for evaluation of iodinated analogues of glucose.

For an iodinated analogue of glucose to be useful for evaluating glucose uptake using single-photon emission computed tomography (SPECT), it must enter the cell via the same transporter as glucose and accumulate within the cell without being degraded. The biological behavior of the iodinated tracer must therefore be similar to that of 2-deoxy-D(-)[1-14C]-glucose (2-DG). In the present study, four experimental models (biodistribution in mouse, isolated rat heart, human erythrocytes in suspension and cultured neonatal rat cardiomyocytes) have been chosen and protocols have been set up which allow for the examination of small quantities of iodinated analogues of glucose. The uptakes of 2-DG and of L(-)[1-14C]-glucose have been measured in these models to establish reference values which will be compared with uptake values for iodinated analogues of glucose.

Animals↗
PubMed1995

Peak expiratory flow rate variability in population surveys. Does the number of assessments matter?

We investigated the effect of reducing the number of daily peak expiratory flow (PEF) measurements on (1) the amplitude of PEF variability and (2) the relationships of this amplitude to bronchial reactivity to methacholine. One hundred seventeen workers (mean age = 38.7 years +/- 9.5; men = 86.3%) recorded their highest of three PEF measurements, every 3 waking hours, ie, 5 times a day, for 7 days, each using a newly purchased peak flowmeter (Vitalograph), and underwent methacholine challenge tests. The variability of PEF of each subject was expressed using the three sets of indices: amp%mean, ie, highest of the daily measurements considered minus the lowest/mean x 100, averaged over 6 days from the second to the seventh, amp%highest (same as amp%mean, but with the highest daily measurements as denominators) and SD%mean (calculated initially as single measures using the data of the 6 days considered, with standard deviation (SD) of each subject's PEF measurements). For each set, we used the indices constructed with the five daily measurements of each day (gold standard), with the first, third, fourth, and fifth, the first, third, and fourth, the first and third, and the first and fourth. The PEF variability was significantly reduced when reducing the number of daily measurements, only when the amp%mean and the amp%highest sets were used. No decrease was observed with the SD%mean set of indices, and SD%mean constructed with the first, third, fourth, and fifth daily measurement was satisfactory. Whatever the sort of index used, three daily measurements were sufficient to identify the group of subjects with excessive variability in relation to methacholine reactivity.

Adult↗