PHARAO laser source flight model: design and performances.

In this paper, we describe the design and the main performances of the PHARAO laser source flight model. PHARAO is a laser cooled cesium clock specially designed for operation in space and the laser source is one of the main sub-systems. The flight model presented in this work is the first remote-controlled laser system designed for spaceborne cold atom manipulation. The main challenges arise from mechanical compatibility with space constraints, which impose a high level of compactness, a low electric power consumption, a wide range of operating temperature, and a vacuum environment. We describe the main functions of the laser source and give an overview of the main technologies developed for this instrument. We present some results of the qualification process. The characteristics of the laser source flight model, and their impact on the clock performances, have been verified in operational conditions.

The resistible growth of health care costs.

Rather than our routinely blamed ageing demography, pharmaceutical promotion and the medical business, not research, are responsible for our ever growing health bill. To keep essential health care affordable, only what has been proved necessary and cost effective should be financed by some kind of risk mutualisation system. Hedonistic care should be left to the free market. From conception to death, a devastating culture of medicalization and therapeutic agressivity has turned naturally inexpensive processes, such as conception, birth, ageing and death, into over-priced medical achievements. The increasing lack of personal and social responsibility triggered by the market, such as junk food, tobacco, drugs, sedentarity or trash media, multiply life-threatening illnesses such as diabetes 2, obesity, cardiovascular diseases and all kinds of cancers. Screenings require millions of participants and intense statistical analysis to prove any efficacy. Screenings, testings and proactive practices make people sick and produce more patients than they save lives , while generating exceptional returns on investments thanks to state and insurance financing; they should be put under public control. New drugs are unaffordable in spite of their dubious efficacy which often relies on biased and underpowered studies. Because they target desperate, debilitating, up to now incurable diseases like metastatic cancers, multiple sclerosis, Alzheimer, polyarthritis, Crohn disease, patients and their families want them by any means and at any price. The answer to the North-South health gap is in a global deal: a declining demographic trend, already well under way and free circulation not only of goods but also of people which would in the long run shape up the age pyramid of a progressively mixed population. That could also save lives at both ends of the human chain: those who die from starvation and those who die from overfeeding.

To screen or not to screen.

All screenings lack efficiency because they rely too often on biaised and underpowered statistics. Healthcare business makes tremendous benefits out of well established and easy profit earning processes from screenings to treatments; therefore patients enlightened consent is under influence. In the wealthiest parts of the world, this field of public health sciences impulses studies with intense statistical analysis of tiny differences. About total and cancer specific death rates, meaningful studies should involve over 1,000,000 people. First, who is going to pay for such studies and, if it takes so many people to be sure, the benefit must be very small. In our lifetime, we believed in many concepts only to realise how wrong we were. This will probably be the case for cancer screening.

Assessment of sensorimotor and cognitive deficits induced by a moderate traumatic injury in the right parietal cortex of the rat.

The purpose of this study was to set-up a battery of behavioral tests to assess sensorimotor and cognitive deficits following a moderate traumatic brain injury (TBI) in rats. Coordinated walking ability was evaluated in an accelerated rotarod test. Vestibulomotor function and fine motor coordination were assessed by using a beam-walking task. Rotarod and beam-walking performances were both altered in injured rats compared to sham-operated and control rats. A more pronounced and longer-lasting deficit was measured in the beam-walking test. Cognitive function was studied by using the Lashley maze paradigm. A spatial localization deficit was significant for 4 weeks posttrauma in TBI rats. The beam-walking task and the Lashley maze are robust and sensitive methods in detecting sensorimotor and cognitive impairment after TBI in rats, respectively. These tests are proposed for evaluating the ability of new pharmacological agents to improve the functional recovery after a TBI in rats.

Inhibition of aflatoxin biosynthesis by phenolic compounds.

The phenolic compounds acetosyringone, syringaldehyde and sinapinic acid inhibited the biosynthesis of aflatoxin B1 (AFB1) by A. flavus. Acetosyringone was the most active among the three compounds, inhibiting aflatoxin level by 82% at 2 m moll-1. The synthesis and accumulation of norsolorinic acid, an aflatoxin biosynthetic intermediate, was also inhibited. These results suggest that at least one step early in the AFB1 biosynthetic pathway is inhibited by the phenolics.

Hepatic ornithine decarboxylase induction by potato glycoalkaloids in rats.

The induction of hepatic ornithine decarboxylase (ODC) activity in rat livers by the potato glycoalkaloids alpha-solanine, alpha-chaconine, and their aglycone solanidine, has been studied. Ip administration of alpha-solanine at 7.5, 15 and 30 mg/kg body weight produced markedly elevated enzyme activity at 4 hr after treatment, with a linear dose response. The increase was four-fold at the lowest dose administered to 12-fold at the highest. ODC activity was measured at 1, 2, 3, 4, 5, 6, 8, and 24hr after alpha-solanine was given. A statistically significant increase in enzyme activity was evident at 3 hr after treatment; maximal activity occurred at 5 hr and was approximately 12 times greater than the dimethylsulphoxide (DMSO) control level. Elevated activities persisted for several hours, decreasing to about one-third of the maximal level at 8 hr. The relative effects of alpha-solanine, alpha-chaconine and solanidine on ODC activities were studied at 4 hr using an equimolar dose of 17 mM/kg body weight. ODC activity induced by alpha-chaconine was higher than that induced by alpha-solanine; the latter activity was two-thirds that of the former. The aglycone solanidine did not induce any increase in activity compared with the DMSO control. ODC activity with dexamethasone, a glucocorticoid, at 4 mg/kg body weight, followed a pattern similar to that of alpha-solanine. However, maximal activity occurred slightly earlier at 4 hr after treatment. The results show that the extent of induced ODC activity depends on the structure of the potato alkaloid.

Inactivation of metalloenzymes by food constituents.

Phenylethylaminoalanine (PEAA), derived from biogenic phenylethylamine and dehydroalanine, inhibited the enzymatic activity of the metalloenzyme, carboxypeptidase A (CPA). The inhibition was maximal at pH 7.0 in the pH range 7-8.5. The extent of inhibition increased with time of treatment and PEAA concentration. N-AcetylPEAA did not inhibit the enzyme, suggesting that the free alpha-NH2 group is required for inhibition. PEAA also inactivated the copper enzyme, polyphenol oxidase (tyrosinase). Comparative studies with three other inhibitors, lysinoalanine, ethylenediaminetetraacetic acid and sodium phytate, suggest that the potency of PEAA as an inhibitor of CPA is similar to that of sodium phytate. Of these four inhibitors and three thiol compounds also tested, PEAA was the least and cysteine the most effective against tyrosinase. The pattern of observations in these studies suggests differences in the mechanisms of action of the inhibitors studied. The formation of PEAA, lysinoalanine and sodium phytate in foods is of possible nutritional and toxicological significance.

Inactivation of metalloenzymes by lysinoalanine, phenylethylaminoalanine, alkali-treated food proteins, and sulfur amino acids.

Synthetic lysinoalanine (LAL) may be a more effective inhibitor of the zinc-containing enzyme carboxypeptidase A than is ethylenediamine tetraacetic acid (EDTA). The enzyme is also inactivated by alkali-treated, lysinoalanine-containing food proteins such as casein, high-lysine corn protein, lactalbumin, soy protein isolate, and wheat gluten, and by alkali-treated zein, which contains no lysinoalanine. Zinc sulfate regenerates only part of the enzymatic activity after exposure to the treated proteins. The extent of inhibition increases with protein concentration and time of treatment. Any inhibition due to phytate is distinct from that due to the treatment. Phenylethylaminoalanine (PEAA), derived from biogenic phenylethylamine, inhibited enzymatic activity of the metalloenzyme carboxypeptidase A (CPA). The inhibition was maximal at pH 7.0 in the pH range 7 to 8.5. The extent of inhibition increased with time of treatment and PEAA concentration. N-acetyl-PEAA did not inhibit the enzyme, suggesting that the free alpha-NH2 group is required for inhibition. PEAA, LAL, sodium phytate, and cysteine also inactivated the copper enzyme, polyphenol, oxidase (tyrosinase) which plays a major role in enzymatic (oxidative) browning of foods. Analogous comparative studies with LAL, EDTA, and sodium phytate suggest that the potency of PEAA as an inhibitor of CPA is similar to that of sodium phytate, and that of the four compounds tested, PEAA is least effective against tyrosinase. Related studies of the iron and copper containing enzyme cytochrome C oxidase showed that EDTA was not inhibitory, PEAA was slightly inhibitory, and LAL and sodium phytate were stronger inhibitors. Mechanistic explanations are offered to account for some of these observations. The possible relevance of these findings to in vivo protein digestion, enzymatic (oxidative) browning of foods, and the mechanism of the lysinoalanine effect on kidney cells are also discussed.

Nutritional improvement of soy flour.

Heating soy flour at 45 degrees C in pH 8.5 Tris buffer for 1 hour in the presence of cysteine or N-acetylcysteine followed by dialysis to remove unreacted thiols resulted in the introduction of new half-cystine residues and lowered trypsin inhibitor content from 37.5 to 6.8 or 4.8 mg/g, respectively, compared to only 14.8 mg/g in the absence of sulfhydryl compounds. Presence of cysteine or N-acetylcysteine during treatment increased protein efficiency ratio (PER) from 0.95 to 2.01 or 2.20, respectively. Corresponding values at 65 degrees C are 1.61, 2.43 and 2.02; and at 75 degrees C, 2.14, 2.53 and 3.19, respectively. Proteins are modified through formation of mixed disulfide bonds, which leads to loss of inhibitory activity and increased protein digestibility and nutritive value.

Arteriographic, Doppler and surgical evaluation of aorto iliac disease and arterial insufficiency of the lower limbs.

The authors compare Doppler and arteriography in aorto iliac obstructive disease. Correlation is high and Doppler combined with induced hyperemia gives highly valuable hemodynamic information which are missed at arteriography. In unilateral iliac lesions, surgery could be planed without further arteriographic investigations. In a group of thoroughly investigated patients submitted to surgery. Doppler and arteriography are compared, the anatomical lesions being used as reference; this study stresses the accuracy of Doppler mainly in unilateral iliac and peripheral lesions.