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Biomedical subjects

P Burnat

Publications and source records attributed to P Burnat.

At least 19 recordsLinked to original sources
PubMed2005

Living high-training low altitude training: effects on mucosal immunity.

Secretory immunoglobulin A (sIgA) is the major immunoglobulin of the mucosal immune system. Whereas the suppressive effect of heavy training on mucosal immunity is well documented, little is known regarding the influence of hypoxia exposure on sIgA during altitude training. This investigation examined the impact of an 18-day Living high-training low (LHTL) training camp on sIgA levels in 11 (six females and five males) elite cross-country skiers. Subjects from the control group (n=5) trained and lived at 1,200 m of altitude, whereas, subjects from the LHTL group (n=6) trained at 1,200 m, but lived at a simulated altitude of 2,500, 3,000 and 3,500 m (3x6-day, 11 h day(-1)) in hypoxic rooms. Saliva samples were collected before, after each 6-day phases and 2 weeks thereafter (POST). Salivary sIgA, protein and cortisol were measured. There was a downward trend in sIgA concentrations over the study, which reached significance in LHTL (P<0.01), but not in control (P=0.08). Salivary IgA concentrations were still lower baseline at POST (P<0.05). Protein concentration increased in LHTL (P<0.05) and was negatively correlated with sIgA concentration after the 3,000 and 3,500 m-phase and at POST (P<0.05 all). Cortisol concentrations were unchanged over the study and no relationship was found between cortisol and sIgA. In summary, data were strongly suggestive of a cumulative negative effect of physical exercise and hypoxia on sIgA levels during LHTL training. Two weeks of active recovery did not allow for proper sIgA recovery. The mechanism underlying this depression of sIgA could be mediated by neural factors.

Adult↗
PubMed2005

[Prolonged succinylcholine-induced apnoea associated with cholinesterase silent plasma variant].

Mivacurium and succinylcholine are short-acting neuromuscular blocking drugs. The duration of their action depends on their rapid hydrolysis by plasma cholinesterase or butyrylcholinesterase. More than thirty genetic variants of this enzyme have been described but the atypical variant is the most frequently involved in prolonged apnoea following the administration of these two myorelaxants. We present one case of patient who presented a five hours long apnoea associated with null cholinesterase activity and detection of a butyrylcholinesterase silent variant (Sil-1, 1 for 100,000 persons in population) after sequencing.

Aged↗
PubMed2005

[Is mild hyperhomocysteinemia an additional risk factor of the metabolic syndrome?].

INTRODUCTION: Metabolic syndrome is a cardiovascular risk factors cluster and hyperhomocysteinemia an obvious independant risk factor. OBJECTIVE: To ascertain if hyperhomocysteinemia is associated with the metabolic syndrome. METHODS: "Epimil" is a prospective epidemiologic survey, which began by a cross-sectionnal study of cardiovascular risk factors in a French population, which then will be followed for ten years for supervision and intervention. Initial data collection, blood pressure measurement, ECG and blood samples (biology and DNA) have been performed. For the metabolic syndrome, we used the criterias of the third report of the national cholesterol education program expert panel on detection, evaluation, and treatment of high blood cholesterol in adults (NCEP ATP III). RESULTS: Out of 2045 men aged from 20 to 58 years (37.7+/-8.7 years), 185 (9%) have metabolic syndrome (at least three criterias), 587 (29%) a blood homocysteine>or=12 micromol/L and 202 (10%)>or=15 micromol/L. Homocysteinemia is 10.97+/-5.01 micromol/L for the whole population and doesn't differ with (11.4+/-6 micromol/L) or without (10.9+/-5 micromol/L) the metabolic syndrome, as does its values distribution. It's not correlate with the body mass index, waist and hip measurements, nor with glycemia, HbA1c, insulin resistance and cardiovascular risk markers (CRPus, microalbuminuria). It weakly correlates with systolic and diastolic blood pressure, creatinine clearance, tobacco use, cholesterolemia, triglycerides and free fatty acids but not with HDL and LDL fractions, nor lipoprotein (a). Among this population, it slightly contributes to the ten years vascular risk evaluated according to Framingham equations or Score system. CONCLUSIONS: Homocysteinemia and the prevalence of hyperhomocysteinemia don't differ with or without the metabolic syndrome and doesn't correlate its main criterias.

Adult↗
PubMed2005

Epidemiology of the metabolic syndrome in 2045 French military personnel (EPIMIL study).

CONTEXT: The Metabolic syndrome is considered to be an important public health problem, but few epidemiological studies have defined the present situation in France. EPIMIL is a prospective epidemiological study that began on February 1, 2003. SUBJECTS AND METHODS: This study was designed to identify the clinical and laboratory parameters of metabolic syndrome and cardiovascular risk factors in a population of 2045 male military personnel based in the Paris region. The initial 1-year cross-sectional study will be followed by a 10-year follow-up and patient care. RESULTS: The 2045 subjects included 185 (9%) presented at least 3 of the 5 NCEP ATP III criteria defining metabolic syndrome. They were significantly older (42.2 +/- 8.5 yrs) than the other subjects (37.3 +/- 8.7 yrs, P<0.001), had a higher BMI (29.5 +/- 3.4 vs 24.8 +/- 2.9 kg/m2, P<0.001) and a greater body weight at age 20 (75.4 +/- 11 vs 70.4 +/- 8.5 kg, P<0.01). Smoking, little physical activity and family histories of diabetes and arterial hypertension were more frequent in these men. While levels of the cholesterol and CRP us were higher, Lp(a) and homocysteine concentrations were normal. Plasma insulin and BMI (r = 0.456 P<0.0001) and plasma insulin and waist circumference (r = 0.446 P<0.0001) were well correlated. Lastly, plasma insulin, free fatty acids and cardiovascular risk increased steadily with the increase in the number of metabolic syndrome criteria. CONCLUSIONS: These results in a large and particularly uniform population of men show the prevalence of metabolic syndrome in adult men, and demonstrate its link with insulin resistance. Men with several risk factors require specific care, particularly for hypertension and dyslipidemia; the effectiveness of this care will be evaluated during the follow-up period.

Adult↗
PubMed2004

Intense training: mucosal immunity and incidence of respiratory infections.

This investigation examined the impact of a multistressor situation on salivary immunoglobulin A (sIgA) levels, and incidence of upper respiratory tract infection (URTI) during the French commando training (3 weeks of training followed by a 5-day combat course). For the URTI, the types of symptoms were classified according to the anatomical location of the infection. Saliva samples were collected (8 a.m.) from 21 males [21 (2) years] before entry into the commando training, the morning following the 3 weeks of training, after the 5-day combat course, and after 1 week of recovery. sIgA, protein and cortisol concentrations were measured. Symptoms of URTI were recorded during the study from health logs and medical examinations. After the 3 weeks of training, the sIgA concentration was not changed, although it was reduced after the 5-day course [from 120 (14) mg l(-1) to 71 (9) mg l(-1), P<0.01]. It returned to pre-training levels within a week of recovery. The incidence of URTI increased during the trial (chi(2)=53.48; P<0.01), but was not related to sIgA. Among the 30 episodes of URTI reported, there were 12 rhino-pharyngitis, 6 bronchitis, 5 tonsillitis, 4 sinusitis and 3 otitis. Cortisol levels were raised after the 3-week training (P<0.01), dropping below baseline after the combat course (P<0.01). Stressful situations have an adverse effect on mucosal immunity and incidence of URTI. However, the relationship between sIgA and illness remained unclear. The large proportion of rhino-pharyngitis indicated that the nasopharyngeal cavity is at a higher risk of infection.

Adaptation, Physiological↗
PubMed2000

High-performance liquid chromatographic determination of cotinine in urine in isocratic mode.

A simple procedure for the determination of cotinine, major metabolite of nicotine in urine, is described. The assay involved a liquid-liquid extraction with dichloromethane in alkaline environment. The extract was dried at ambient temperature under a gentle stream of nitrogen. The residue was dissolved in 300 microl of mobile phase and 30 microl aliquot was injected via an automatic sampler into the liquid chromatograph and eluted with the mobile phase (10-9%, v/v methanol and acetonitrile, respectively in potassium dihydrogenphosphate buffer adjusted to pH 3.4) at a flow rate of 1 ml/min on a C8 Symmetry cartridge column (5 microm, 150 mm x 3.9 mm, Waters) at 25 degrees C. The eluate was detected at 260 nm. Internal standard was 2-phenylimidazole. Sensitive and specific, this technique was performed to test urine of diabetic patients (smokers and non-smokers) admitted in an endocrinology service. Urinary cotinine seems to be a better marker of smoking status than thiocyanates.

Calibration↗
PubMed1998

[Hereditary xanthinuria, rare cause of hypo-uric acidemia. 2 cases].

BACKGROUND: Hypouricemia can be observed in uncommon situations as in our two patients with hereditary xanthinuria. CASE REPORTS: In the first case, hereditary xanthinuria was discovered in a 36-year-old man when routine tests revealed hypouricemia. In the second case, a 76-year-old woman, hypouricemia was also a fortuitous discovery. She had major xanthinuria and a radiotranslucid lithiasis in the right kidney. DISCUSSION: Hereditary xanthinuria is characterized by hypouricemia, low urinary urate excretion and increased concentration of xanthine and to a lesser extent hypoxanthine. The disease results from a defect in xanthine oxidase and is considered to be transmitted by autosomal recessive heredity. This rare metabolic disorder is more often asymptomatic and detected by routine chemistry. Development of xanthine lithiasis is directly related to the low solubility of xanthine and is the main complication of the disease, occurring in 30-40% of patients. There is no effective treatment and the only useful measure is to prevent xanthine urolithiasis by maintaining urinary output above 2 l/day.

Adult↗
PubMed1998

High-performance liquid chromatographic determination of modafinil and its two metabolites in human plasma using solid-phase extraction.

A simple procedure for the simultaneous determination of modafinil, its acid and sulfone metabolites in plasma is described. The assay involved an extraction of the drug, metabolites and internal standard from plasma with a solid-phase extraction using C18 cartridges. These compounds were eluted by methanol. The extract was evaporated to dryness at 40 degrees C under a gentle stream of nitrogen. The residue was redissolved in 250 microl of mobile-phase and a 30 microl aliquot was injected via an automatic sampler into the liquid chromatograph and eluted with the mobile-phase (26%, v/v acetonitrile in 0.05 M orthophosphoric acid buffer adjusted to pH 2.6) at a flow-rate of 1.1 ml/min on a C8 Symmetry cartridge column (5 microm, 150 mm x 3.9 mm, Waters) at 25 degrees C. The eluate was detected at 225 nm. Intra-day coefficients of variation ranged from 1.0 to 2.9% and inter-day coefficients from 0.9 to 6.1%. The limits of detection and quantitation of the assay were 0.01 microg/ml and 0.10 microg/ml respectively.

Administration, Oral↗
PubMed1998

[Cholinesterases].

OBJECTIVE: To review current data on butyrylcholinesterase. DATA SOURCES: Search through Medline data bases of articles in French or English. STUDY SELECTION: Original articles and case reports were selected. Letters to editor were excluded. DATA EXTRACTION: The articles were analyzed in order to obtain current data on biochemical structure, action, major pathological variations, especially with regard to the recent informations obtained by molecular biology concerning the identification of genetic variants. DATA SYNTHESIS: Butyrylcholinesterase must be differentiated from acetylcholinesterase, which cannot hydrolyse succinylcholine. The physiological action of butyrylcholinesterase remains unknown, although it can hydrolyse many drugs. Excluding genetical mutations, several physiopathological situations alter butyryl-cholinesterase activity. Butyrylcholinesterase activity assessment does not allow the diagnosis of genetic variants. Whatever the origin, only deficits of more than 50% modify significantly the metabolism of succinylcholine or mivacurium. The diagnosis of a prolonged neuromuscular blockade is obtained with systematic monitoring of the neuromuscular function in case of administration of mivacurium or succinylcholine. Mivacurium should only be re-injected when one response at train of four is obtained. In case of prolonged neuromuscular blockade, the anticholinesterasic agent should not be administered when no response at train of four is obtained. The biochemical methods using inhibitors (dibucaine, fluoride) of the butyrylcholinesterase and a familial study lead to the diagnosis in most cases because the atypical and fluoride variants are the most frequent. When results are doubtful, genetic molecular methods with the use of PCR and restriction enzymes allow a rapid diagnosis.

Acetylcholinesterase↗
PubMed1998

Prolonged mivacurium neuromuscular block in children.

The authors report two cases of prolonged neuromuscular block after administration of mivacurium in children with previously undiagnosed plasma cholinesterase deficiency related to homozygous atypical genotype. Their anaesthetic management is described as well as determination of the phenotype of both children and their family.

Anesthesia Recovery Period↗
PubMed1996

[Ecstasy: psychostimulant, hallucinogen and toxic substance].

MDMA or 3,4-methylenedioxymethamphetamine, more commonly called "ecstasy", is a drug classified as a stupefiant and increasingly used by young people for its stimulant and hallucinogen effects. This popular designer drug is often used in techno or rave parties and perceived by users as relatively harmless. It has however been associated with disorders of thermoregulation and has been the cause of several deaths. In addition, the drug has been shown to destroy serotonin receptors in the brain in the monkey and leads to serious physchiatric disorders and liver damage in man.

Animals↗
PubMed1987

[Phenotype of plasma cholinesterase in prolonged apnea and sensitivity to succinylcholine].

90% of the injected dose of succinylcholine is hydrolysed by serum cholinesterase (E.C.3.I.I.8) Abnormal variants of serum cholinesterase lead to prolonged apnea. This report presents the results of 62 serum cholinesterase phenotyping including 12 cases of prolonged apneas. One clinical case of prolonged apnea in a patient homozygous for the atypical cholinesterase gene is presented with a study of his genealogy. The phenotypes were established on the basis of dibucaïne, fluorure, chloride and propranolol differential inhibition. The frequency and significance of the various phenotypes is discussed.

Anesthesia, General↗