Interactive computerized microscopy as a tool for quantifying vascular remodelling effects of diabetes and V1a receptor antagonist SR 49059 on rat mesenteric arterial bed.

A methodology using interactive computerized microscopy (ICM) was developed to quantify in the mesenteric arterial bed the morphometric changes associated with diabetes and the influence of treatment with SR 49059, an antagonist of vasopressin V1a receptors. Four groups of rats were studied: untreated normal (N) or streptozotocin- (60 mg/kg i.v.) induced diabetic (D), and treated (0.4 mg/g SR 49059 included in food) normal (NT) or diabetic (DT) animals. Treatment was initiated 4 days after diabetes induction and continued for 3 weeks. Nested (hierarchical) analysis of variance of ICM data was performed on raw diameter or after logarithmic normalization of area and nuclei values. Diabetes was associated with an increase in arterial diameters, and in total vessel, wall, media, adventitia, and lumen areas. The same parameters, with the exception of the lumen, were also increased in DT as compared to D. The number of nuclei in the media or adventitia was increased in D as compared to N, and in DT as compared to D. In summary, ICM is allowed to further characterize the vascular mesenteric changes and describe for the first time the enlargement of adventitia associated with diabetes. Our study also suggested that the blockade of Via receptors is unable to prevent diabetes-related vascular changes, although the slight increase in food intake associated with SR 49059 treatment may have had an indirect influence on angiopathy development.

Therapeutic isoniazid monitoring using a simple high-performance liquid chromatographic method with ultraviolet detection.

Simultaneous measurement of isoniazid and its main acetylated metabolite acetylisoniazid in human plasma is realized by high-performance liquid chromatography. The technique used is evaluated by a factorial design of validation that proved to be convenient for routine drug monitoring. Plasma samples are deproteinized by trichloroacetic acid and then the analytes are separated on a microBondapak C18 column (Waters). Nicotinamide is used as an internal standard. The mobile phase is 0.05 M ammonium acetate buffer (pH 6)-acetonitrile (99:1, v/v). The detection is by ultraviolet absorbance at 275 nm. The validation, using the factorial design allows one to: (a) test the systematic factors of bias (linearity and matrix effect); (b) estimate the relative standard deviations (RSDs) related to extraction, measure and sessions assay. The linearity is confirmed to be within a range of 0.5 to 8 microg/ml of isoniazid and 1 to 16 microg/ml of acetylisoniazid. This method shows a good repeatability for both extraction and measurement (RSD INH=3.54% and 3.32%; RSD Ac.INH=0.00% and 5.97%), as well as a good intermediate precision (RSD INH=7.96%; RSD Ac.INH=15.86%). The method is also selective in cases of polytherapy as many drugs are associated (rifampicin, ethambutol, pyrazinamide, streptomycin). The matrix effect (plasma vs. water) is negligible for INH (3%), but statistically significant for Ac.INH (11%). The application of this validation design gave us the possibility to set up an easy and suitable method for INH therapeutic monitoring.

Infrared, raman, and 13C NMR spectra of two crystalline forms of (1R,3S)-3-(p-thioanisoyl)-1,2,2-trimethylcyclopentanecarboxylic acid.

A comparative structural analysis of the two polymorphic forms of (1R,3S)-3-(p-thioanisoyl)-1,2,2-trimethylcyclopentanecarboxylic acid has been performed with infrared, Raman, and 13C NMR spectroscopy. The results are compared with those of the crystallographic and thermal studies on the two forms published in previous papers. The enantiotropism of the polymorphs as well as the differences in the conformation of the carboxyl group and the resulting intermolecular hydrogen bonds were confirmed by the infrared and Raman studies.

Development of spray-dried acetaminophen microparticles using experimental designs.

Experimental factorial designs were built to investigate the effects of five parameters on production yields and moisture contents of spray-dried products. These factors concerned both the solution feed (drug concentration, colloidal silica concentration and polymer/drug ratio) and the spray dryer (inlet temperature and feed rate). Three formulations containing cellulose derivatives and acetaminophen were tested. The aim of the study was to optimize the operating conditions to maximize production yields while minimizing moisture contents. First screening experiments consisting of fractional factorial designs revealed the most significant factors to be inlet temperature, feed rate and their interaction for both formulations containing sodium carboxymethylcellulose and feed rate and colloidal silica concentration for the formulation containing microcrystalline cellulose. Then, the optimal operating conditions were estimated by response surface methodology. Central rotational composite designs showed quadratic models were adequate. New assays were carried out using these last conditions to evaluate both the repeatability and reproducibility of the spray-drying technique. Yields above 80% and moisture content of approximately 1% were reached. The characterization of microparticles revealed the poor flowability of the spray-dried products due to significant cohesiveness and very small size (less than 55 microm).

Serum zinc and somatic growth in children with growth retardation.

A possible role for zinc deficiency in some cases of growth retardation in southern France was investigated. Control values for zinc for 160 children (age = 12.5 +/- 2.4 yr) are 0.85 +/- 0.22 mg/L (mean +/- 2 SD). Twenty-five children with low serum zinc values (less than 0.63 mg/L) and 25 matched short children with normal serum zinc values (greater than 0.63 mg/L) were studied. Children in the two groups did not differ significantly in age, pubertal development, stature, and weight. For the 25 children whose serum values were low, we found significantly lower values for bone age delay, growth velocity in mm/month, as well as the ratio between calculated growth velocity and theoretical growth velocity for the bone age (so that zincemia was correlated to these parameters in the whole sample of 50 subjects). Nevertheless, no significant difference could be found between the two groups for serum somatomedin C, serum osteocalcin values, and GH responses to the GH stimulatory tests (exercise test, overnight sampling, insulin-induced hypoglycemia, arginine test). Therefore, low serum zinc is associated with a retardation in both somatic growth and pubertal maturation.

Effects of zinc supplementation on blood rheology during exercise.

We previously reported a higher blood viscosity at corrected hematocrit (45%) (explained by a higher value of erythrocyte rigidity) in football players with low serum zinc (Zn) and thus presumably Zn deficiency; subjects with low serum zinc had also an impairment in performance. This interventional study was undertaken in order to assess the effects of zinc supplementation (compared to placebo) on blood rheology and performance either at rest or during exercise. Ten male healthy volunteers (age: 26+/-1.3 yr; weight 67.9+/-2.24 kg; height 177+/-3 cm) received at random order either zinc (20 mg/day) and placebo, according to a double blind cross-over procedure, during seven days. In each case on the eighth day they performed a 25 min submaximal exercise-test. At rest blood viscosity at corrected hematocrit 45% (gamma = 1000 s(-1)) was lower after Zn (3.56+/-0.14 vs. 4.13+/-0.16 mPa.s, p = 0.009), explained by a lower RBC rigidity index 'k' according to Quemada's equation (1.65+/-0.07 vs. 1.84+/-0.08, p = 0.03). Hematocrit and plasma viscosity were unchanged, but RBC aggregation was decreased (laser retrodiffusion-derived aggregation time 'Ta' 3.52+/-0.51 vs. 2.75+/-0.59, p = 0.02). The increase in blood viscosity during exercise is lower after Zn than placebo. Blood viscosity at corrected hematocrit 45% remains unchanged during exercise after Zn, yet it increases after placebo. RBC rigidity index 'k' remains lower during exercise after Zn. The rating of perceived exertion (Borg's scale) at the 20th minute of exercise is lower after zinc (5.6+/-0.4 vs. 6.6+/-0.4, p = 0.008). This study confirms that Zn improves erythrocyte deformability, decreases the exercise-induced acute increase in blood viscosity, and improves exercise tolerance. Since Zn deficiencies are not unfrequent in sportsmen, these findings may be potentially relevant to sports nutrition.

Serum zinc and blood rheology in sportsmen (football players).

We aimed at investigating relationships between zinc status, blood rheology and blood glucose during exercise. Twenty-one professional football players underwent a triangular maximal exercise test on cycloergometer, with progressively increasing work loads until VO2max. On the whole these subjects had a low serum zinc because nine of them had a hypozincemia (0.54 +/- 0.01 mg/l) which suggested a zinc deficiency. Subjects with low serum zinc were able to perform a lower power output (123 +/- 8.71 vs. 166.27 +/- 14.84 watts, p = 0.029) and exhibited a higher increase in blood lactate during exercise (7.51 +/- 0.81 vs. 5.57 +/- 0.33 mmol/l, p = 0.024) resulting in a lower 2 mmol lactate threshold (44.7 +/- 3.9% vs. 58.9 +/- 4.8% of maximal power output, p = 0.04). They were less able to maintain their plasma glucose and exhibited a tendency towards hypoglycemia (p = 0.0153). Hypozincemia was associated with a higher viscometric RBC rigidity index (p = 0.0009), and this index was negatively correlated to serum zinc (r = -0.68, p = 0.7 x 10(-3)). Blood viscosity at high shear rate (MT90 viscosimeter) corrected for hematocrit (45%) remained higher during exercise in these hypozincemic subjects (p = 0.003). This study suggests that zinc status may influence blood rheology during exercise, either by its direct action on RBC flexibility (demonstrated in vitro) or by its effect on lactate accumulation which may in turn modify erythrocyte fexibility.

[Analysis of the distribution of HDL-cholesterol and (VLDL + LDL)-cholesterol in hepatic and intestinal disorders]. / Analyse de la répartition du cholestérol des HDL et des (VLDL + LDL) dans des atteintes hépatiques et intestinales.

Total cholesterol (Ch-T), HDL cholesterol (Ch-HDL) and (VLDL + HDL) cholesterol (Ch-(VLDL + LDL) were evaluated in 78 cases of various hepatodigestive diseases (11 icterus, 14 hepatitis, 30 chronic alcoholisms, 8 Crohn's diseases and 15 haemorragic rectocolitis (RCH], and in 76 control subjects. High cholesterol levels were found in icterus, but its distribution between lipoproteic fractions remained unchanged. In the group of hepatitis, a deficit in Ch-(VLDL + LDL) was elicited by a significant decrease of Ch-(VLDL + LDL)/Ch-T ratio. The same was observed in chronic alcoholism. In Crohn's disease the levels of every cholesterol fraction were low, while in RCH they were not significantly different from those of the control group. But, in RCH, the Ch-HDL/Ch-T ratios showed significant low values with concommitant higher values of Ch-(VLDL + LDL)/Ch-HDL ratios, suggesting that, in RCH, the metabolism of cholesterol is unbalanced with a deficit of Ch-HDL. In conclusion, the evaluation of cholesterol in lipoproteic fractions by a simple assay may contribute to specify the diagnostic of these disorders.

Comparison of four methods for digesting food samples for determination of trace levels of cadmium by flameless atomic absorption spectrophotometry.

We compared 4 digestion procedures, namely, sulfuric-nitric acid in an open flask, nitric acid under pressure, sulfuric-nitric acid with refluxing, and nitric-hydrochloric-peroxide with refluxing, for the determination of cadmium by flameless atomic absorption spectrophotometry in 3 foodstuffs: rice, beef, and cream cheese. The foodstuffs were homogenized and divided into several batches for analysis. The results were evaluated using a 2-way cross analysis of variance. The study revealed that the digestion procedure was a highly significant factor (P less than 10(-4] in the analysis of the 3 foods; whereas the nature of the foodstuffs was not significant for rice and meat and only slightly significant (P less than 10(-2] for cream cheese. When the foodstuffs were spiked with a known amount of cadmium, we observed a loss of the metal when the sulfuric-nitric acid procedure in an open flask and the nitric-hydrochloric-peroxide digestion procedure were used. Taken together, the results of the present study indicate that the choice of the reagents used for digestion of foodstuffs is a crucial factor for cadmium determination by flameless atomic absorption spectrophotometry.

Distribution of the amatoxins and phallotoxins in Amanita phalloides. Influence of the tissues and the collection site.

The toxin composition of 25 Amanita phalloides carpophores collected from three sites in Franche-Comté (France) differing in their geological and pedological characteristics was determined and the factors involved in the variations of the toxin concentration in the tissues were identified. The concentrations of the main amatoxins (beta-amanitin, alpha-amanitin, gamma-amanitin) and phallotoxins (phallacidin, phallisacin, phalloidin, phallisin, phalloin) in the six tissues constituting the carpophore, i.e. the cap (C), gills (G), ring (R), stipe (S), bulb (B) and volva (V) were evaluated by using high-performance liquid chromatography. The results analysed statistically showed that the toxin concentrations were tissue dependent, leading to classification of the tissues into two groups (B, V) and (C, G, R, S). The (B, V) group was distinguished by high amounts of phalloidin, phallisin and phallisacin, and the (C, G, R, S) group by the predominance of the amatoxins. The characteristics of the soil of the collection site also affected the toxin concentrations; however, this effect differed from one site to another and was not similar for all the tissues. Finally, the mean toxin profile in the carpophores from the three sites was evaluated. This study underscores the fact that environmental factors and mainly the soil type clearly have an effect on the toxin composition of A. phalloides carpophores.

Variations of lactose and oligosaccharides in milk from women of blood types secretor A or H, secretor Lewis, and secretor H/nonsecretor Lewis during the course of lactation.

Variations of lactose and oligosaccharides in human milk were studied over a 3-month lactation period by dialysis, chromatography on Bio-gel P-2 column, paper chromatography, colorimetric analysis and gas chromatography. Milk samples were collected from donors of various blood and secretor types. An increase in the concentration of lactose was noted: 59.25 +/- 1.61 to 72.17 +/- 1.35 g/l for the group of secretor A secretor Lea Leb individuals, and from 62.25 +/- 1.35 to 73.15 +/- 3.45 g/l for the group of secretor H secretor Lea Leb individuals. A decrease in the concentration of oligosaccharides was also found: from 16.71 +/- 0.99 to 7.90 +/- 1.29 g/l and from 18.51 +/- 0.74 to 7.33 +/- 0.65 g/l, respectively, for these same groups. In secretor H nonsecretor Lewis individuals, the concentration of lactose increased from 67.97 +/- 3.09 to 77.42 +/- 1.88 g/l, and the concentration of oligosaccharides decreased from 13.27 +/- 0.40 to 3.47 +/- 0.33 g/l. Analysis of oligosaccharide composition by chromatography showed that variations are in relation to the secretor Lewis type. All oligosaccharides decreased equally throughout the lactation period, regardless of the blood group. The decrease was more rapid, however, in the nonsecretor Lewis individuals. In these individuals, the absence of certain oligosaccharides is not compensated by an overproduction of the other oligosaccharides present or by biosynthesis of structurally different oligosaccharides. The origin of these oligosaccharides is discussed.

[Comparative study of 2 methods to determine the in vivo bactericidal activity of antiseptics]. / Etude comparative de deux méthodes de détermination de l'activité bactéricide in vivo des antiseptiques.

In France in 1990, there is no standardized method to study the bactericidal activity in vivo of antiseptics. A comparative study of the Williamson-Kligmann techniques (on the epidermis of the forearm) and of the bag of Gaschen (on the hands) has been carried out by using 11 products and 10 volunteers for each of them. On the forearm, the rates of reduction of the number of bacterias numbered in decimal logarithms are significantly much higher to those measured on the hand. After having stated the advantages and drawbacks of each of these two techniques, an account fort the differences in the activity that have been observed is suggested. None of these two techniques is universal and one or the other has to be used according to the therapeutic prescription (antisepsy of the normal skin or of the hands) of the patent medicine.

Variations in oligosaccharides and lactose in human milk during the first week of lactation.

Variations in oligosaccharides and lactose in human milk were studied in 15 mothers during the first week of lactation. The neuraminyloligosaccharides and heavy neutral oligosaccharides increased slightly from days 2 to 5 postpartum and appeared to decrease until day 7. The lacto-N-difucohexaoses, lacto-N-fucopentaoses, and lacto-N-tetraose increased until day 5 and then decreased. Lactodifucotetraose and the fucosidolactoses decreased substantially until day 5 (p less than 0.05) and appeared to stablize in the following days. Lactose increased until day 5 (p less than 0.05) and continued to increase thereafter. Lactose was negatively correlated with total oligosaccharides (p less than 0.10). The fluctuations observed in total oligosaccharides from days 2 to 5 postpartum and their subsequent stabilization and regular decrease during lactation confirm the hypothesis of Kulski and Hartmann that mammary secretion occurs in three periods: colostrum for the first 36 h postpartum, transitional milk from days 2 to 5 postpartum, and mature milk after day 5. The oligosaccharide variations we found corresponded to those of other milk constituents observed by other authors. The significance of the oligosaccharide variations is discussed.

Discriminant carbohydrate components of human milk according to donor secretor types.

Because of the variability of human milk carbohydrate composition, we determined the discriminant carbohydrate components of the milk of 18 mothers according to their ABH and Lewis secretor types during the first week of lactation. Comparative chromatograms revealed that the presence of neuraminyloligosaccharides is linked to the ABH secretor groups, and that the absence of oligosaccharides with Lea or Leb specificity is linked to the Lewis nonsecretor types. The study of carbohydrate composition according to donor secretor types consisted of measuring 16 variables from 69 samples. Analysis of variance showed significant differences between groups: high levels of N-acetylneuraminic acid and low levels of galactose distinguished ABH secretors from nonsecretors (p less than 0.001). In the ABH secretor groups, A and H secretors had higher N-acetylglucosamine contents than B and AB secretors (p less than 0.001) and lower galactose levels (p less than 0.001). The Lewis secretor groups were distinguished by significantly higher fucose levels (p less than 0.001). The ABH(+)Le(a-b-) group had higher lactose contents than the other groups (p less than 0.01).

[Adsorbed plant extracts, use of extracts of dried seeds of Orthosiphon stamineus benth]. / Elaboration d'extraits végétaux adsorbés, réalisation d'extraits secs d'Orthosiphon stamineus benth.

The work presented is related to the elaboration and the control of spray dried vegetable extracts of Orthosiphon Stamineus Benth. From these studies, it feasibility of the spray dried extracts. The best result concerning a pulverulent structure and the stability under moisture conditions is obtained using Aerosil 200. Pharmacological studies on rats have shown a diuretic activity under our experimental conditions with alcoholic and water extracts.

Diurnal variations and within the feed in lactose and oligosaccharides of human milk.

Variations of lactose and oligosaccharides in human milk were studied during the day and the feed, by dialysis, chromatography on Bio-gel P-2 column, paper chromatography, colorimetric analysis and gas chromatography. Progressive changes were found during the day, but not during the feed. A diurnal variation in milk lactose was seen, which was the inverse of the oligosaccharides. Significant negative correlations between lactose and oligosaccharides were seen in the afternoon and evening (p less than 0.05). The minimal mean value of lactose at 19.00 h is 58.64 +/- 5.28 g/l and the maximal mean values of oligosaccharides was 17.93 +/- 2.28 g/l. The data are discussed with regard to other milk constituents and to their possible physiological relevance.

[Blood levels of dehydroepiandrosterone sulfate (DHEA-S) and the risk of breast cancer]. / Taux sanguin du sulfate de la déhydroépiandrostérone (DHEA-S) et risque de cancer du sein.

In North American women at low or high risk of developing breast cancer, as assessed by an epidemiologic questionnaire, the plasma concentration of dehydroepiandrosterone sulfate shows a statistically significant circannual variation. In adolescents, in all seasons, circulating dehydroepiandrosterone sulfate is a classifier of the risk of developing breast cancer, a relatively low concentration of this hormone being associated with an increased risk.

[Radioprotective agents derived from benzonitrile]. / Agents radioprotecteurs dérivés du benzonitrile.

Benzonitriles have been evaluated as potential antiradiation agents in mice. They have an interesting radioprotective activity, in particular 3,5-dinitrobenzonitrile, one of the non-sulfur-containing radioprotective compounds which presents a consistent DRF (DRF = 1.35).