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2.
Phys Rev Lett ; 131(9): 093401, 2023 Sep 01.
Article En | MEDLINE | ID: mdl-37721832

Circular Rydberg atoms (CRAs), i.e., Rydberg atoms with maximal orbital momentum, are highly promising for quantum computation, simulation, and sensing. They combine long natural lifetimes with strong interatomic interactions and coupling to electromagnetic fields. Trapping individual CRAs is essential to harness these unique features. We report the first demonstration of CRAs laser trapping in a programmable array of optical bottle beams. We observe the decay of a trapped rubidium circular level over 5 ms using a novel optical detection method. This first optical detection of alkali CRAs is both spatially and level selective. We finally observe the mechanical oscillations of the CRAs in the traps. This work opens the route to the use of circular levels in quantum devices. It is also promising for quantum simulation and information processing using the full extent of Rydberg manifolds.

3.
Infect Dis Now ; 52(8): 432-440, 2022 Nov.
Article En | MEDLINE | ID: mdl-36116761

OBJECTIVES: To determine the predictors of a positive SARS-CoV-2 test in a pediatric ambulatory setting. PATIENTS AND METHODS: We performed a cross-sectional prospective study (November 2020-February 2022) of 93 ambulatory settings in France. We included symptomatic children < 15 years old tested for SARS-CoV-2. For each period corresponding to the spread of the original strain and its variants (period 1: original strain; period 2: Alpha, period 3: Delta; period 4: Omicron), we used a multivariate analysis to estimate adjusted odds ratios (aORs) associated with COVID-19 among age, signs, symptoms or contact, and 95 % confidence intervals (95CIs). RESULTS: Of 5,336 children, 13.9 % (95CI 13.0-14.8) had a positive test. During the first three periods, the positivity rate ranged from 5.6 % (95CI 4.6-6.7) to 12.6 % (95CI 10.8-14.6). The main factors associated with a positive test were contact with an infected adult at home or outside the home (aOR 11.5 [95CI 4.9-26.9] to 38.9 [95CI 19.3-78.7]) or an infected household child (aOR 15.0 [95CI 4.8-47.1] to 28.4 [95CI 8.7-92.6]). By contrast, during period 4, aORs for these predictors were substantially lower (2.3 [95CI 1.1-4.5] to 5.5 [95CI 3.2-7.7]), but the positivity rate was 45.7 % (95CI 42.3-49.2). CONCLUSIONS: In pediatric ambulatory settings, before the Omicron period, the main predictor of a positive test was contact with an infected person. During the Omicron period, the odds of these predictors were substantially lower while the positivity rate was higher. An accurate diagnostic strategy should only rely on testing and not on age, signs, symptoms or contact.


COVID-19 , SARS-CoV-2 , Adult , Humans , Child , Adolescent , COVID-19/diagnosis , COVID-19/epidemiology , Cross-Sectional Studies , Prospective Studies
4.
Infect Dis Now ; 52(3): 130-137, 2022 May.
Article En | MEDLINE | ID: mdl-35172217

BACKGROUND: Beyond sex, age, and various comorbidities, geographical origin and socioeconomic deprivation are associated with Coronavirus Disease (COVID-19) morbidity and mortality in the general population. We aimed to assess factors associated with severe forms of COVID-19 after a hospital emergency department visit, focusing on socioeconomic factors. METHODS: Patients with laboratory-confirmed COVID-19 attending the emergency department of Béclère Hospital (France) in March-April 2020 were included. Postal addresses were used to obtain two geographical deprivation indices at the neighborhood level. Factors associated with hospitalization and factors associated with adverse outcomes, i.e. mechanical ventilation or death, were studied using logistic and Cox analyses, respectively. RESULTS: Among 399 included patients, 321 were hospitalized. Neither geographical origin nor socioeconomic deprivation was associated with any of the outcomes. Being male, older, overweight or obese, diabetic, or having a neuropsychiatric disorder were independent risk factors for hospitalization. Among 296 patients hospitalized at Béclère Hospital, 91 experienced an adverse outcome. Older age, being overweight or obese, desaturation and extent of chest CT scan lesions>25% at admission (aHR: 2.2 [95% CI: 1.3-3.5]) and higher peak CRP levels and acute kidney failure (aHR: 2.0 [1.2-3.3]) during follow-up were independently associated with adverse outcomes, whereas treatment with hydrocortisone reduced the risk of mechanical ventilation or death by half (aHR: 0.5 [0.3-0.8]). CONCLUSION: No association between geographical origin or socioeconomic deprivation and the occurrence of a severe form of COVID-19 was observed in our population after arrival to the emergency department. Empirical corticosteroid use with hydrocortisone had a strong protective impact.


COVID-19 , COVID-19/epidemiology , Female , Hospitalization , Hospitals , Humans , Hydrocortisone , Male , Obesity/epidemiology , Overweight , SARS-CoV-2 , Social Factors
5.
Phys Rev Lett ; 124(12): 123201, 2020 Mar 27.
Article En | MEDLINE | ID: mdl-32281867

Rydberg atoms are remarkable tools for quantum simulation and computation. They are the focus of an intense experimental activity, mainly based on low-angular-momentum Rydberg states. Unfortunately, atomic motion and levels lifetime limit the experimental timescale to about 100 µs. Here, we demonstrate two-dimensional laser trapping of long-lived circular Rydberg states for up to 10 ms. Our method is very general and opens many opportunities for quantum technologies with Rydberg atoms. The 10 ms trapping time corresponds to thousands of interaction cycles in a circular-state-based quantum simulator. It is also promising for quantum metrology and quantum information with Rydberg atoms, by bringing atom-field interaction times into unprecedented regimes.

6.
Rev Sci Instrum ; 91(3): 033202, 2020 Mar 01.
Article En | MEDLINE | ID: mdl-32259984

We demonstrate a method for accurately locking the frequency of a continuous-wave laser to an optical frequency comb under conditions where the signal-to-noise ratio is low, too low to accommodate other methods. Our method is typically orders of magnitude more accurate than conventional wavemeters and can considerably extend the usable wavelength range of a given optical frequency comb. We illustrate our method by applying it to the frequency control of a dipole lattice trap for an optical lattice clock, a representative case where our method provides significantly better accuracy than other methods.

7.
Phys Rev Lett ; 123(14): 143001, 2019 Oct 04.
Article En | MEDLINE | ID: mdl-31702181

High-harmonic generation (HHG) is widely used for up-conversion of amplified (near) infrared ultrafast laser pulses to short wavelengths. We demonstrate that Ramsey-comb spectroscopy, based on two such pulses derived from a frequency-comb laser, enables us to observe phase effects in this process with a few mrad precision. As a result, we could perform the most accurate spectroscopic measurement based on light from HHG, illustrated with a determination of the 5p^{6}→5p^{5}8s^{2}[3/2]_{1} transition at 110 nm in ^{132}Xe. We improve its relative accuracy 10^{4} times to a value of 2.3×10^{-10}. This is 3.6 times better than shown before involving HHG, and promising to enable 1S-2S spectroscopy of He^{+} for fundamental tests.

8.
Arch Pediatr ; 22(3): 283-6, 2015 Mar.
Article Fr | MEDLINE | ID: mdl-25524289

Gradenigo syndrome is caused by petrous inflammation, also called petrositis. It includes acute otitis media, diplopia, and homolateral retroorbital pain due to trigeminal and abducens nerve injury. We describe a child with petrositis secondary to acute otitis media. The lack of otoscopic abnormality and the presence of bilateral headache made the diagnostic difficult. After complementary investigations searching for an intracranial process, the diagnosis was made based on brain and skull base dimensional computed tomography.


Otitis Media/complications , Petrositis/etiology , Acute Disease , Female , Humans , Infant
9.
Transl Psychiatry ; 4: e401, 2014 Jun 17.
Article En | MEDLINE | ID: mdl-24937095

In addition to the classical motor symptoms, motivational and affective deficits are core impairments of Parkinson's disease (PD). We recently demonstrated, by lesional approaches in rats, that degeneration of the substantia nigra pars compacta (SNc) dopaminergic (DA) neurons is likely to have a crucial role in the development of these neuropsychiatry symptoms. We have also shown that, as in clinical investigations, chronic treatment with levodopa or the DA D2/D3 receptor (D2/D3R) agonist ropinirole specifically reverses these PD-related motivational deficits. The roles of specific DA receptor subtypes in such reversal effects remain, however, unknown. We therefore investigated here the precise involvement of D1, D2 and D3R in the reversal of the motivational and affective deficits related to SNc DA neuronal loss. Three weeks after bilateral and partial 6-hydroxydopamine (6-OHDA) SNc lesions, rats received 14 daily intraperitoneal administrations of the selective D1R agonist SKF-38393 (2.5 or 3.5 mg kg(-1)), the selective D2R agonist sumanirole (0.1 or 0.15 mg kg(-1)), or the preferring D3R gonist PD-128907 (0.1 or 0.15 mg kg(-1)). Anxiety-, depressive-like and motivated behaviors were assessed in an elevated-plus maze, a forced-swim test, and an operant sucrose self-administration procedure, respectively. All DA agonists attenuated anxiety- and depressive-like behaviors. However, only PD-128907 reversed the motivational deficits induced by 6-OHDA SNc lesions. This effect was blocked by a selective D3R (SB-277011A, 10 mg kg(-1)), but not D2R (L-741,626, 1.5 mg kg(-1)), antagonist. These data provide strong evidence for the role of D3R in motivational processes and identify this receptor as a potentially valuable target for the treatment of PD-related neuropsychiatric symptoms.


Behavior, Animal/drug effects , Dopamine Agonists/pharmacology , Dopamine Antagonists/pharmacology , Dopaminergic Neurons/pathology , Motivation/drug effects , Parkinson Disease/drug therapy , Receptors, Dopamine D3/physiology , Substantia Nigra/injuries , Animals , Disease Models, Animal , Dopamine Agonists/administration & dosage , Dopamine Antagonists/administration & dosage , Rats , Receptors, Dopamine D1/agonists , Receptors, Dopamine D2/agonists , Receptors, Dopamine D3/agonists , Receptors, Dopamine D3/antagonists & inhibitors
10.
Mol Psychiatry ; 19(3): 358-67, 2014 Mar.
Article En | MEDLINE | ID: mdl-23399912

Parkinson's disease (PD) involves the degeneration of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNc) that is thought to cause the classical motor symptoms of this disease. However, motivational and affective impairments are also often observed in PD patients. These are usually attributed to a psychological reaction to the general motor impairment and to a loss of some of the neurons within the ventral tegmental area (VTA). We induced selective lesions of the VTA and SNc DA neurons that did not provoke motor deficits, and showed that bilateral dopamine loss within the SNc, but not within the VTA, induces motivational deficits and affective impairments that mimicked the symptoms of PD patients. Thus, motivational and affective deficits are a core impairment of PD, as they stem from the loss of the major group of neurons that degenerates in this disease (DA SNc neurons) and are independent of motor deficits.


Affect/physiology , Corpus Striatum/physiology , Dopamine/physiology , Dopaminergic Neurons/physiology , Motivation/physiology , Parkinson Disease/physiopathology , Parkinson Disease/psychology , Substantia Nigra/physiology , Ventral Tegmental Area/physiology , Affect/drug effects , Animals , Behavior, Animal/drug effects , Behavior, Animal/physiology , Disease Models, Animal , Dopamine/metabolism , Dopaminergic Neurons/drug effects , Dopaminergic Neurons/metabolism , Male , Microinjections , Motivation/drug effects , Neural Pathways/drug effects , Neural Pathways/physiology , Oxidopamine/administration & dosage , Rats , Substantia Nigra/drug effects , Substantia Nigra/metabolism , Ventral Tegmental Area/drug effects , Ventral Tegmental Area/metabolism
11.
Gynecol Obstet Fertil ; 33(4): 253-8, 2005 Apr.
Article Fr | MEDLINE | ID: mdl-15894212

Zinc, an essential trace element, plays a critical role in normal growth and development, cellular integrity and many biological functions, including protein synthesis and nucleic acid metabolism. Since all these are involved in cell division and growth, zinc is believed to be important for foetal growth and development. Zinc requirement is increased during pregnancy but the lack of a valid indicator precludes a true estimate of zinc deficiency in pregnancy even in developed countries. This review examines the possibility that a gestational deficiency of zinc can adversely affect the pregnancy outcome. Preliminary human data suggest a beneficial effect of prenatal zinc supplementation trials in particular on infant's neurobehavioral development. In the light of the currently available information, zinc supplementation at therapeutic load (30 mg/day) as it is proposed for the treatment of hormonal skin disorders to adolescents, cannot be toxic.


Pregnancy Outcome , Zinc , Dietary Supplements , Female , Humans , Nutritional Requirements , Pregnancy , Pregnancy Complications , Prenatal Care , Zinc/administration & dosage , Zinc/adverse effects , Zinc/deficiency
12.
Gynecol Obstet Fertil ; 32(3): 245-50, 2004 Mar.
Article Fr | MEDLINE | ID: mdl-15123124

Considering that young women have a high risk of iron store deficiency, the iron supplementation is largely proposed during pregnancy. However, a selective supplementation reserved to anaemia women, must be preferred to a systematic supplementation which improves biological parameters of mothers but have no effect on newborns. Iron is a potentially toxic element and a not justified, supplementation could expose to high iron level and to an oxidative stress which is also observed in pregnancy pathologies (preeclamptia, gestational diabetes). Furthermore a non controlled increase of erythrocyte mass by iron supplementation could also alter the placenta exchange. As a precaution, iron supplementation may be reserved to anaemia women or with high anaemia risk. For others, nutritional advises must permit to reach iron recommendation.


Anemia, Iron-Deficiency/prevention & control , Dietary Supplements , Iron/administration & dosage , Pregnancy Complications, Hematologic/prevention & control , Adolescent , Adult , Female , Humans , Nutritional Requirements , Pregnancy , Pregnancy Outcome , Prenatal Nutritional Physiological Phenomena
13.
Eur J Clin Nutr ; 58(1): 52-9, 2004 Jan.
Article En | MEDLINE | ID: mdl-14679367

OBJECTIVE: To investigate the possible beneficial effects of a micronutrient supplementation to apparently healthy pregnant women on maternal biological status and new born anthropometric characteristics. SETTING: Departments of Obstetric of the University Hospital of Grenoble (France) and Lyon (France), Laboratoire of Biology of Oxidative Stress, UFR de Pharmacie. Grenoble (France). STUDY DESIGN: Double-blind, randomized placebo-controlled intervention trial. SUBJECTS: A total of 100 apparently healthy pregnant women were recruited at 14+/-2 weeks of gestation to delivery. At the end, they were 65 women to follow out the study. INTERVENTIONS: Daily consumption over gestation of a micronutrients supplement or placebo. MAIN OUTCOME MEASURES: Plasma micronutrient levels and oxidative stress parameters were measured in mothers at 14 and 38 weeks of gestation. New born's anthropometric characteristics were measured at delivery. RESULTS: In the supplemented group, folic acid, vitamin C, E, B2, B6 and beta-carotene levels were higher than in the placebo group. Oxidative stress parameters were not different between the groups. Birth weights were increased by 10% and the number of low newborn weights (<2700 g) decreased significantly when the mother received the supplementation. Maternal plasma Zn levels were positively correlated to the newborn heights. CONCLUSION: A regular intake of a micronutrient supplement at nutritional dose may be sufficient to improve micronutrient status of apparently healthy pregnant women and could prevent low birth weight of newborn.


Birth Weight/drug effects , Dietary Supplements , Infant, Newborn/growth & development , Micronutrients/administration & dosage , Nutritional Status , Adult , Anthropometry , Double-Blind Method , Female , Health Status , Humans , Infant, Low Birth Weight , Micronutrients/blood , Oxidative Stress/drug effects , Placebos , Pregnancy , Pregnancy Complications/prevention & control , Pregnancy Outcome , Zinc/administration & dosage , Zinc/blood
15.
Gynecol Obstet Fertil ; 28(7-8): 509-17, 2000.
Article Fr | MEDLINE | ID: mdl-10996962

Several studies have shown that estrogen replacement therapy protects postmenopausal women against coronary artery disease. This protective effect has been ascribed to the hormone's effect on serum lipids, as well as a direct action on the vascular wall. Concurrent administration of a progestin to protect women from the risk of endometrial hyperplasia may alter the protective effects of estrogen. The aim of this study was to assess the evolution of the endothelial function in postmenopausal women given a sequential combination of oral 2 mg estradiol valerate for 11 days, followed by 2 mg estradiol valerate associated with 1 mg cyproterone acetate for ten days (Climène). Each 21-day sequence was followed by a seven-day treatment-free interval. The women received a three-month treatment course. Thirty-one healthy postmenopausal women participated in the study (median age: 51 years; range: 45-59 years). Flow-mediated dilatation (FMD), a reflection of endothelium-dependent vasomotor function, increased from 8.47% at baseline (range: 4.57-11.02%) to 9.64% (range: 7.07-13.12%) at the end of the first treatment cycle; i.e., a 15% increase over baseline (P < 0.0001). FMD further increased after three treatment cycles to 10.59% (range: 8.09-15.22%); i.e., a 28.6% increase over baseline (P < 0.0001). FMD at the end of the first combined sequence or after the 11 days of estradiol only were similar (delta = 0.25%; range: -2.31-5.81%; not significant). In conclusion, in postmenopausal women, a three-month sequential treatment combining estradiol valerate and estradiol valerate plus cyproterone acetate (Climène) has beneficial effects on endothelial function as demonstrated by the evolution of the FMD. There was no decrease in the effect of estradiol on FMD when cyproterone acetate was added to estradiol.


Cyproterone Acetate/administration & dosage , Endothelium, Vascular/drug effects , Endothelium, Vascular/physiology , Estradiol/analogs & derivatives , Estradiol/administration & dosage , Postmenopause , Progesterone Congeners/administration & dosage , Arteries/drug effects , Arteries/physiology , Cyproterone Acetate/therapeutic use , Estradiol/therapeutic use , Estrogen Replacement Therapy , Estrogens, Conjugated (USP)/administration & dosage , Estrogens, Conjugated (USP)/therapeutic use , Female , Humans , Middle Aged , Progesterone Congeners/therapeutic use , Vasodilation
16.
J Reprod Med ; 45(6): 498-500, 2000 Jun.
Article En | MEDLINE | ID: mdl-10900585

BACKGROUND: Limb-girdle muscular dystrophy is a muscular disease determined genetically. Few papers have been published on this disorder in pregnancy. Several authors reported on delivery by cesarean section because of the risk of dystocia. CASE: A woman with limb-girdle muscular dystrophy had two pregnancies with normal vaginal delivery and follow-up. No obstetric complications related to the disease occurred. CONCLUSION: A trial of labor is possible in patients with limb-girdle muscular dystrophy if no obstetric contraindications exist.


Delivery, Obstetric , Muscular Dystrophies , Obstetric Labor Complications , Trial of Labor , Adult , Female , Humans , Infant, Newborn , Leg , Male , Pregnancy
18.
Lipids ; 33(8): 765-71, 1998 Aug.
Article En | MEDLINE | ID: mdl-9727606

A viscous hydrocolloid (guar gum, GG; 2.5% of the diet) or a steroid sequestrant (cholestyramine; 0.5% of the diet) was included in semipurified diets containing 0.2% cholesterol to compare the cholesterol-lowering effects of each agent in rats. In the present model, GG significantly lowered plasma cholesterol (-25%), especially in the density < 1.040 kg/L fraction, whereas cholestyramine was less potent. Bile acid fecal excretion significantly increased only in rats fed cholestyramine, similar to the cecal bile acid pool; the biliary bile acid secretion was accelerated by GG, but not their fecal excretion, whereas GG effectively enhanced neutral sterol excretion. As a result, the total steroid balance (+13 micromol/d in the control) was shifted toward negative values in rats fed the GG or cholestyramine diets (-27 or -50 micromol/d, respectively). Both agents induced liver 3-hydroxy-3-methylglutaryl-CoA reductase, but cholestyramine was more potent than GG in this respect. The present data suggest that, at a relative low dose in the diet, GG may be more effective than cholestyramine in lowering plasma cholesterol by impairing cholesterol absorption and by accelerating the small intestine/liver cycling of bile acids, which is interestingly, accompanied by reduction of bile acid concentration in the large intestine.


Bile Acids and Salts/metabolism , Cholesterol/metabolism , Dietary Fiber/metabolism , Galactans/metabolism , Mannans/metabolism , Animals , Biliary Tract/metabolism , Body Weights and Measures , Cecum/metabolism , Cholesterol/blood , Cholestyramine Resin/metabolism , Feces/chemistry , Fermentation , Hydrogen-Ion Concentration , Hydroxymethylglutaryl CoA Reductases/metabolism , Lipids/blood , Liver/enzymology , Liver/metabolism , Male , Plant Gums , Rats , Rats, Wistar , Sterols/analysis
19.
Lipids ; 32(9): 953-9, 1997 Sep.
Article En | MEDLINE | ID: mdl-9307936

The effects of partially hydrolyzed, nonviscous, guar gum (PHGG) on cholesterol metabolism and digestive balance have been compared with those of native guar gum (GUAR) in rats adapted to 0.4% cholesterol diets. Both types of guar gum elicited acidic fermentations in the large intestine, but only GUAR effectively lowered plasma cholesterol (P < 0.001), chiefly in the triglyceride-rich lipoprotein fraction. The biliary bile acid excretion was significantly enhanced in rats fed GUAR (P < 0.05), as well as the intestinal and cecal bile acid pool (P < 0.001). In rats fed GUAR and to a lesser extent in those fed PHGG, the fecal excretion of bile acids and neutral sterol was higher than in controls (P < 0.01). The digestive balance (cholesterol intake-steroid excretion) was positive in control rats (+47 mumol/d), whereas it was negative in rats fed GUAR (-20 mumol/d), which could involve a higher rate of endogenous cholesterol synthesis. In rats fed PHGG, the steroid balance remained slightly positive. Liver 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase activity was very low (22 pmol/min/mg protein), owing to cholesterol supplementation, in control rats or in rats fed PHGG, whereas it was markedly higher (+463%) in rats fed GUAR. In conclusion, even if PHGG does alter some parameters of the enterohepatic cycle of cholesterol and bile acids, its effects are not sufficient to elicit a significant cholesterol-lowering effect. The intestinal (ileal or cecal) reabsorption of bile acids was not reduced, but rather increased, by GUAR; nevertheless the intestinal capacities of reabsorption were overwhelmed by the enlargement of the digestive pool of bile acids. In the present model, induction of HMG-CoA reductase probably takes place in the presence of elevated portal bile acid concentrations.


Anticholesteremic Agents/pharmacology , Bile Acids and Salts/metabolism , Cholesterol/metabolism , Galactans/pharmacology , Mannans/pharmacology , Animals , Bile/metabolism , Body Weight , Cecum/growth & development , Cecum/metabolism , Cholesterol/blood , Dietary Fats , Feces , Hydrogen-Ion Concentration , Hydroxymethylglutaryl CoA Reductases/metabolism , Intestinal Absorption , Lipids/analysis , Lipids/blood , Lipoproteins/analysis , Lipoproteins/blood , Liver/chemistry , Liver/enzymology , Liver/metabolism , Male , Organ Size , Plant Gums , Rats , Rats, Wistar
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