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A Nicolas

Publications and source records attributed to A Nicolas.

At least 181 records · Page 10Linked to original sources

[Pelvic cancer].

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Antineoplastic Agents↗

Advantages of capillary electrophoresis for determination of choline in pharmaceutical preparations.

Assay of choline in pharmaceutical preparations was realized by capillary zone electrophoresis (CZE) coupled with indirect UV detection. The suitability of several background electrolytes was investigated to optimize the separation of choline from other components such as amino acids, betaine and cations. Final operating conditions were as follows: a 75 microns x 50 cm uncoated fused-silica capillary with an electrolyte consisting of 5 mM creatinine pH 3.2, a voltage of 25 kV, a temperature of 25 degrees C and an UV detection at 210 nm. Choline migrates in less than 5 min and full selectivity vs other analytes was achieved. Validation data compared with those obtained with HPLC demonstrated the interest of CZE.

Choline↗

Rapid liquid chromatographic assay of glutathione in cultured cells.

A rapid, sensitive and selective method for the assay of glutathione in cultured cells has been developed using ion-pair reversed phase rapid high performance liquid chromatography. The use of a 4 micron particle, 5 cm long column (Superspher 100 RP 18 end-capped) allowed complete analysis of glutathione within 3 min. A postcolumn derivatization reaction with o-phthalaldehyde and fluorometric detection made the assay fully selective with regard to other endogenous thiols and sensitive (the detection limit was 0.5 ng of glutathione injected). The linearity range was between 0.1 and 2.0 microgram/mL with good repeatability (relative standard deviation less than 5% for the lowest concentration quantitated). Recoveries of GSH from cultured cell samples were above 98%. The rapid analysis enabled the processing of a large number of samples in a short time (up to 20 per hour). The method was applied to the measurement of the intracellular glutathione amount in V79 fibroblasts along cell growth in culture.

Animals↗

Prevalence of headache in a representative sample of the population in a French department (Haute-Vienne-Limousin).

In 1986-1987, a neuroepidemiologic survey was undertaken to study the prevalence of the most frequently encountered neurologic disorders, and in particular headache, in a representative sample of the population in the Haute-Vienne Department (Limousin). A door-to-door survey was made using a protocol developed by the W.H.O. at the beginning of the 1980's. The calculated prevalences (according to Poisson's distribution) per 100,000 inhabitants were 5,059 for nonmigraine headache, and 4,270 for migraine headache. This disorder preferentially affected young adults and essentially involved females. It was the most frequently encountered disorder (50%) during the different surveys of similar methodology.

Adolescent↗

[Blood lactate in the steeplechase horse: triangular and rectangular series of steps during short duration races].

Five steeplechase race horses were observed during incremental and constant-load exercises with the aim of separating effects of work rate and time on blood lactate. Each independent exercise (an incremental and three constant load tests) was a sequence of three two-minute runs, separated by two one-minute rest intervals for jugular blood sampling. The following observations were made: 1. During constant load exercises, in the five horses, blood lactate stabilized below 4 mmol.l-1: lactatemia critical velocity (LVC) = 3.33 +/- 0.16 mmol.l-1. Nevertheless, VCL, critical lactate velocity inducing LVC, was not statistically different from VS4, velocity inducing a 4 mmol.l-1 blood lactate during incremental tests. Remaining reticent on the meaning of "lactate threshold" often attributed to VS4, an incremental exercise thus seemed pertinent for routine long-term surveys of endurance. 2. If delta L is the blood lactate increase within a single short run, delta L increases linearly with running velocity for an incremental test, allowing the calculation of a "null" velocity, the highest velocity for which there is no significant lactate increase. For independent runs, delta L increased exponentially with velocity, with noticeable differences between horses. This individual short-term functional adaptation variability could be considered in assessment and follow-up of race horse fitness.

Animals↗

Expression patterns of L-plastin isoform in normal and carcinomatous breast tissues.

Plastins are members of a family of actin-binding proteins which exhibit a tissue-specific expression pattern. L-plastin, which is specifically expressed in hematopoietic cell lineage, has been proposed to be involved in the control of cell adhesion and motility. This protein is also frequently expressed in cell lines derived from mammary solid tumors and therefore might be involved in cancer invasion and metastasis. We have analysed plastin expression in normal and carcinomatous breast tissues in vivo by immunohistochemistry and immunoblotting approaches using specific plastin isoform antibodies. L-plastin was not detected in normal epithelial cells of the mammary gland whereas a staining of myoepithelial cells was observed in 50% of the cases. In breast carcinomas, a significant immunostaining of malignant epithelial cells was observed in 4 of the 29 cases analysed (13.8%). No correlation between L-plastin expression and tumor size, histological grade or lymph node status was observed. In contrast, L-plastin was found expressed in 4 of the 11 estrogen and progesterone receptors negative tumors (p = 0.039). The potential role of plastin expression in the tumor process is discussed.

Adult↗

[A study of the serological response of Sudanese children to three associated immunizations (measles, tetanus, meningococcal A meningitis) (author's transl)].

The authors first emphasize the efficiency and economic value of associated immunizations in developping countries. They report the first data collected in a campaign of immunization with a single injection of an extemporaneous mixture of antimeasles, antitetanus and antimeningococcal meningitis vaccines. This campaign took place in the Republic of Suddan from may 1976 to july 1977 and concerned 87 children. The specifications of each vaccine as well as the procedures of vaccination and serological control are given. The study of serological rates shows: -- a good response for measles with, in Africa, an optimal âge of 6 months and a new injection 6 months later; -- a low and late antibodies rise in tetanus with a good immunological memory giving way to an acute rise under a 2nd injection one year later; -- an immediate increase of the basic low rate of meningococcic antibodies existing in most Suddanese children before the injection. The authors consider the advantage of using also anti C meningococcal vaccine and to add an inactivated poliomyelitic vaccine. They give notice of the good stability in tropical environment of the vaccinal mixture they used.

Bacterial Vaccines↗