GPU-enabled real-time optical frequency comb spectroscopy and a photonic readout.

We describe a GPU-enabled approach for real-time optical frequency comb spectroscopy in which data is recorded, Fourier transformed, normalized, and fit at data rates up to 2.2 GB/s. As an initial demonstration we have applied this approach to rapidly interrogate the motion of an optomechanical accelerometer through the use of an electro-optic frequency comb. We note that this approach is readily amenable to both self-heterodyne and dual-comb spectrometers for molecular spectroscopy as well as a photonic readout where the approach's agility, speed, and simplicity are expected to enable future improvements and applications.

Single-modulator, direct frequency comb spectroscopy via serrodyne modulation.

Traditional electro-optic frequency comb spectrometers rely upon the use of an acousto-optic modulator (AOM) to provide a differential frequency shift between probe and local oscillator (LO) legs of the interferometer. Here we show that these modulators can be replaced by an electro-optic phase modulator (EOM) which is driven by a sawtooth waveform to induce serrodyne modulation. This approach enables direct frequency comb spectroscopy to be performed with a single dual-drive Mach-Zehnder modulator (DD-MZM), allowing for lower differential phase noise. Further, this method allows for simpler production of integrated photonic comb spectrometers on the chip scale.

High dynamic range electro-optic dual-comb interrogation of optomechanical sensors.

An interleaved, chirped electro-optic dual comb system is demonstrated for rapid, high dynamic range measurements of cavity optomechanical sensors. This approach allows for the cavity displacements to be interrogated at measurement times as fast as 10 µs over ranges far larger than can be achieved with alternative methods. While the performance of this novel, to the best of our knowledge, readout approach is evaluated with an optomechanical accelerometer, this method has a wide range of applications including temperature, pressure, and humidity sensing as well as acoustics and molecular spectroscopy.

Electro-optic frequency combs for rapid interrogation in cavity optomechanics.

Electro-optic frequency combs were employed to rapidly interrogate an optomechanical sensor, demonstrating spectral resolution substantially exceeding that possible with a mode-locked frequency comb. Frequency combs were generated using an integrated-circuit-based direct digital synthesizer and utilized in a self-heterodyne configuration. Unlike approaches based upon laser locking, the present approach allows rapid, parallel measurements of full optical cavity modes, large dynamic range of sensor displacement, and acquisition across a wide frequency range between DC and 500 kHz. In addition to being well suited to measurements of acceleration, this optical frequency comb-based approach can be utilized for interrogation in a wide range of cavity optomechanical sensors.

Evidence of genetic variability for digestive efficiency in the growing pig fed a fibrous diet.

Energy digestibility in the growing pig increases with BW increase and may differ between breeds of pigs or between lines selected on criteria other than digestion. However, little is known about the variability in energy digestibility within a line or a breed of pigs, especially when fibrous diets are fed. For this purpose, 20 Large White castrated male growing pigs originating from four boars (five per boar), and three to four sows per boar, were fed a high dietary fibre (DF) diet (18% NDF) and measured over 10 consecutive weeks (30 to 95 kg BW range) for their apparent faecal energy, nitrogen and organic matter digestibility. Each week, faeces were totally collected over 5 days and the feed dry matter intake over the same days was recorded. All digestibility coefficients increased regularly (P < 0.001) over the experimental periods or with BW increase (+0.6 point/10 kg BW increase for energy); this rate of increase was not affected by boar origin (no interaction; P > 0.05). The digestibility coefficients were affected by boar origin (P < 0.005 for energy), with about 2 points for energy between the extremes (81.7% v. 79.5%), and there was no marked interaction between boar origin and period. These preliminary results suggest the possibility of selecting growing pigs for an increased digestive efficiency when fed high DF diets.

Gabapentin premedication: assessment of preoperative anxiolysis and postoperative patient satisfaction.

BACKGROUND: Gabapentin reduces anxiety in psychiatric patients. In this prospective, randomized, double-blinded, placebo-controlled study, we investigated whether a single dose of gabapentin as a premedicant reduces preoperative anxiety, and improves patient satisfaction. MATERIALS AND METHODS: After Institutional Review Board approval and written consent, 210 patients were randomly allocated into 3 groups of oral premedication: placebo, hydroxyzine 75 mg, or gabapentin 1200 mg. Anxiety level was assessed 3 times, using a 100-mm visual analogue scale: before premedication, in the preoperative holding area, and just before induction of general anaesthesia. In the postoperative period, patients were asked about their satisfaction with their premedicant. Data were presented as mean +/- SD. VAS scores were analyzed by repeated-measures analysis of variance followed by a Bonferroni test as appropriate. The chi-square test was used to analyze categorical data. All p values less than 0.05 was considered statistically significant. RESULTS: Baseline anxiety was not statistically different among the 3 groups. Anxiety level in the gabapentin group was significantly lower in the holding area, and before induction of anaesthesia (20 mm +/- 21), than in the hydroxyzine group (33 mm +/- 26 ; p = 0.023) and in the placebo group (36 mm +/- 28; p = 0.004). Anxiety decreased significantly overtime only in the gabapentin group. The gabapentin and hydroxyzine groups had a higher proportion of "satisfied or extremely satisfied" patients (73% and 70% respectively) as compared to the placebo group (48%, p = 0.006). CONCLUSION: A single dose of gabapentin has proven to be an effective premedication to reduce preoperative anxiety.

[Assessment of the budgetary impact of treatment guidelines in type II diabetes mellitus in France]. / Evaluation de l'impact budgétaire de l'application des recommandations de bonne pratique dans le diabète de type II en France.

BACKGROUND: Type II diabetes mellitus is associated with an increasing prevalence and incidence, and with a heavy economic burden in Western countries. As a consequence, health authorities consider that avoidance or delay of occurrence of diabetes-related micro- and macro-angiopathic complications is a public health priority, leading to the definition of treatment guidelines. The aim of the study was to assess the budgetary impact of the application of the French guidelines. METHODS: Etiologic cost ratios. RESULTS: Our results conclude that 10% decrease in body mass index (BMI) among overweight patients, smoking cessation, initiation to undertake a preventive treatment with low-dose aspirin, initiation to undertake or intensify blood pressure control, initiation to undertake or intensify lipidic control, and shift to biguanides among overweight patients are factors associated with significant benefits (avoided costs) which compensate for the increase in treatment costs. The main beneficial strategies are, in decreasing order, initiation to undertake a preventive treatment with low-dose aspirin, smoking cessation, and control of BMI. CONCLUSION: Our results support interest in reinforcing the application of current treatment guidelines for type II diabetes mellitus.

Patient-controlled interscalene analgesia after shoulder surgery: catheter insertion by the posterior approach.

Insertion and maintenance of an interscalene catheter is technically challenging using lateral or anterior approaches. We report a technique to provide continuous brachial plexus blockade through a 48-h infusion of ropivacaine 0.1% (5 mL/h with a 5 mL bolus dose, 20-min lockout interval) using a catheter inserted with cannula-over-needle technique on the posterior side of the neck in 120 patients undergoing shoulder surgery. All catheters were successfully placed. There were no technical complications (impossibility to thread catheter, accidental vascular, epidural or subarachnoid location), catheter dislodgment, or analgesic solution leakage. Dysphonia, Horner's syndrome, and difficulty breathing were observed in 12 patients, four patients, and one patient, respectively. One patient complained of minor paresthesia that spontaneously resolved. Three patients complained of cervical pain. Pain scores as well as ropivacaine requirement via a patient-controlled analgesia device were low. Evaluation of acute and nonacute complications in a large-size study is needed to compare efficacy and safety of this approach with existing techniques.

Ketamine does not decrease postoperative pain after remifentanil-based anaesthesia for tonsillectomy in adults.

BACKGROUND: There are conflicting results concerning the pre-emptive effect of ketamine on central sensitization following surgery. The aim of this prospective, randomized, double-blind, placebo-controlled study was to assess the effect of the N-methyl-D-aspartate receptor antagonist ketamine on postoperative morphine consumption and pain score after remifentanil-based anaesthesia in adult patients scheduled for tonsillectomy. METHODS: We studied 40 adult patients undergoing elective tonsillectomy. Total intravenous anaesthesia was induced and maintained with remifentanil (0.125-1.0 microg kg(-1) min(-1)) and propofol target-controlled infusion. Patients in group K received a bolus dose of ketamine 0.5 mg kg(-1) immediately after anaesthetic induction, followed by a continuous infusion of 2 microg kg(-1) min(-1). Saline was administered in the same sequence in group S. Propofol, remifentanil, and the study drug infusions were discontinued at the end of surgery. RESULTS: Intraoperative remifentanil consumption (0.57 +/- 0.18 in group K vs. 0.55 +/- 0.14 microg kg(-1) min(-1) in group S), morphine requirement in the PACU (11 +/- 3 in group K vs. 9 +/- 4 mg in group S) and in the ward (22 +/- 11 in group K vs. 25 +/- 14 mg in group S), median time to first analgesia in the ward (338 +/- 126 in group K vs. 328 +/- 144 min in group S), and VAS pain scores were comparable in both groups. CONCLUSION: Small-dose of ketamine does not seem to be a useful adjunct to remifentanil-based anaesthesia during short, painful surgical procedures.

[Congenital achromatopsia: electroretinogram in early diagnosis]. / Achromatopsie congénitale: interêt de l'électrorétinogramme pour le diagnostic précoce.

PURPOSE: Achromatopsia is a hereditary disease responsible for congenital low vision. Patients present with nystagmus, abnormal visual behavior or photophobia. Only the electroretinogram (ERG) can confirm the diagnosis in infants. PATIENTS AND METHODS: Thirty children referred for nystagmus or low vision were included in this retrospective study. A complete ophthalmological examination, an ERG and when possible a color vision test (Ishihara, Farnsworth 15 Hue test) was done. A Ganzfeld ERG was performed in accordance with ISCEV standards in patients more than 6 years of age. In younger patients, a simplified method using electroluminescent diode stimulation was used and a comparative ERG in accordance with ISCEV standards was performed when the patients were old enough. RESULTS: The ERG response was identical in children and adults. It confirmed the diagnosis of achromatopsia: the scotopic components obtained in dark adapted conditions were normal, (scotopic a-wave, b2 wave). The photopic components, recorded in light-adapted conditions, in order to inhibit the scotopic response (photopic wave, b1 wave), were not recordable. The color vision tests confirmed color blindness; however, in some patients color denomination was correct. CONCLUSION: The simplified ERG procedures performed in our series were reliable in detecting achromatopsia. However, it may not be sufficient to discriminate complete from incomplete achromatopsia.

[Labour epidural analgesia in Martinique: evaluation of quality and accessibility to epidural analgesia by the patients in level one obstetric clinic]. / Analgésie péridurale de travail en Martinique: évaluation de la qualité et de l'accessibilité à l'analgésie péridurale par les parturientes dans une clinique obstétricale de niveau 1.

OBJECTIVES: The main aim of this study was to evaluate real-life experience and the quality of labor epidural analgesia (LEA) by the patients, from the anaesthesia consultation to leaving the clinic after childbirth. STUDY DESIGN: Descriptive study. PATIENTS AND METHODS: This study took place over a period of 8 weeks, at the level I obstetric clinic in Martinique. One hundred and thirty-four successive patients completed an anonymous questionnaire following childbirth. RESULTS: During the study period (134 patients completed the questionnaire, corresponding to 100% return) 127 women had asked for LEA (94%), which was possible in 94%, with a patient satisfaction level of 94% and an average mark for quality at 18/20. The quality of information given at the anaesthesia consultation was judged excellent for 97%, and 91% were reassured by the consultation. The delay between the demand and the LEA procedure was less than 15 min in 63%, and in 39% the procedure was done during the night. The procedure was painless in 63%, and 97% of women were ready to begin the same procedure again. CONCLUSION: This study seems to underline the fact that the needs and the acceptability of LEA are the same in Martinique as in mainland France. This study does not support the hypothesis of the cultural barrier to justify the low level of LEA in the Overseas Departments. An obvious result seems to be that good organization of anaesthesia and obstetric services results in a natural increase in LEA demand.

[Economic repercussions of cardiac insufficiency in France]. / Répercussion économique de l'insuffisance cardiaque en France.

The aim of the article is to review economic and public health consequences of congestive heart failure in France. This disease with an increasing prevalence induces for the social security system and the society a high cost; 85 to 93% of this cost are bound to hospitalizations, most of them avoidable. New modalities of care are to be chosen in order to improve the management of heart failure and to contain costs. In this context, multidisciplinary interventions based on patients' education are experimented taking care to assure a greater role to health actors working in the ambulatory sector (GPs, private cardiologists, nurses).

Factors influencing the long-term results of endodontic treatment: a review of the literature.

The purpose of this review of the literature is to examine the factors and their influence on the outcome of endodontic treatments, and also to attempt to have an authors' consensus concerning the impact of these factors on long-term results. The documentary research was conducted using the meta-analysis principles of critical reading of the literature. Two groups of factors can be identified regarding the outcome of endodontic treatments: those which influence the success of the procedure and those which do not significantly affect the success rate. Agreement is obtained in all studies on two major factors, the preoperative periapical status and the apical limit of the obturation, which appear to strongly influence the success of endodontic therapy. This review highlights the methodological problems of retrospective studies and points out the need for consensus regarding the evaluation criteria of root canal therapy.

[Pharmaco-epidemiological study on antipsychotic drug prescription in French Psychiatry: Patient characteristics, antipsychotic treatment, and care management for schizophrenia]. / Etude pharmaco-épidémiologique de la prescription des antipsychotiques en milieu psychiatrique en France -

UNLABELLED: In 2000, a one week national survey was conducted among 202 psychiatrists (129 participants) in France, from hospitals and clinics, private or public. The first 20 inpatients and 10 outpatients prescribed at least one antipsychotic drug (age range 18-65), were included. The diagnostic procedure was standardized with a structured interview: the Mini International Neuropsychiatric Interview (MINI). A total 2 068 patients were included, among whom 892 (43.1%) reached the criteria of schizophrenia according ICD-10. We present here data on these latter patients. Mean age was 38.8 years; with 38.8% females. Median duration of current antipsychotic treatment was 0.5 year in inpatients and 2 years in outpatients. Median duration of any antipsychotic treatment was 10 years, without difference between groups. Comorbid situations (anxiety disorder, depression and suicidal risk) were found in 33.1% of schizophrenic patients, with higher frequency among inpatients in private hospitals (54.8%) than in other groups. 46.8% patients were prescribed at least 2 neuroleptics, and 73.6% at least one non-neuroleptic drugs. Cyamemazine accounted for 16.6% of all neuroleptics drugs, and 56% of patients were prescribed an atypical antipsychotic (risperidone, olanzapine, amisulpride or clozapine). Atypical drugs accounted for 59.4% of patients who were prescribed only one neuroleptic drug. Inpatients had more neuroleptics coprescription than outpatients (mean 1.8 vs 1.4 drugs), with higher daily dose. In addition, inpatients had more other psychotropics prescribed (mean 1.5 vs 1.1 drugs). Overall, more other psychotropic drugs were prescribed among patients with -, than those without - comorbid situations (1.7 vs 1.2 drugs). Median time since admission, at the time of the study, were similar in private and public hospitals (107 vs 99 days) but maximal time since admission was respectively 2.8 and 48.9 years. Visit frequency for outpatients was more than one every two weeks for 43.1% in private and 24.7% in public clinics. Among inpatients only we found a difference between private and public hospitals for polypharmacy of non neuroleptics psychotropics, (mean 1.9 vs 1.5). In outpatients, long acting depot accounted for 26.6% of neuroleptics treatments in public clinics and 15.4% in private clinics. Finally, we found that polypharmacy among outpatients increased with duration of antipsychotic treatment. CONCLUSION: in France, important differences are reported in antipsychotic prescription for schizophrenia between in- and outpatients. Current antipsychotic prescription is more recent in inpatients than in outpatients, with similar duration of overall antipsychotic treatment. Inpatients have more drug prescription, antipsychotics and other psychotropics, than outpatients. Differences are less important between private and public providers. Inpatients in private hospitals receive more non neuroleptic drugs than in public hospitals, and depot antipsychotics are more used among patients of public clinics. Long term inpatients are found in public hospitals only. Outpatients follow up is more intensive in private than in public clinics.

[Economic assessments of head and neck cancers: a review]. / Evaluations economiques des cancers de la tête et du cou: un etat des lieux.

The aim of this study is to perform a review of the literature on economic studies in the area of head and neck cancer (including the cancers of the buccal cavity, the larynx, and the pharynx). French and international literature (as reported on Medline and OHE-IFPMA databases) has been reviewed. This research demonstrated the lack of economic data in this field. In France, only one study was found, assessing the cost of the treatment of head and neck cancer in hospital to 29 billions French Francs including 2.3 billions linked to head and neck cancer. This relative indifference is possibly due to the heterogeneity and the low incidence of the studied pathologies. In addition, the research highlighted the great interest of dealing with quality of life in such physically and psychologically disabling illnesses. To facilitate the decision making and to allow optimal resource allocation in the area of costly health strategies, we should develop in France an economic evaluation of the head and neck cancer, while taking care of integrating the notion of quality of life into the analysis.

Aqueous flare induced by heparin-surface-modified poly(methyl methacrylate) and acrylic lenses implanted through the same-size incision in patients with diabetes.

PURPOSE: To compare the degree of blood-aqueous barrier (BAB) breakdown in eyes of diabetic patients after phacoemulsification and implantation of heparin-surface-modified poly(methyl methacrylate) (PMMA) or soft hydrophobic acrylic intraocular lenses (IOLs) performed using the same technique with the same incision size to determine the influence of the IOLs on postoperative inflammation independent of other surgical factors. SETTING: Department of Ophthalmology, University of Paris XIII, Bobigny, France. METHODS: In a prospective study, 44 eyes of 31 diabetic patients with or without mild to moderate diabetic retinopathy were randomly assigned to receive an HSM PMMA IOL (22 eyes) or a soft hydrophobic acrylic IOL (22 eyes) after standardized phacoemulsification surgery. Both types of IOLs had a 6.0 mm optic, were inserted unfolded, and were placed in the bag through a calibrated 6.0 mm superior scleral incision. Anterior chamber flare was measured preoperatively and 1, 7, 30, and 240 days postoperatively using the Kowa 500 laser flare meter. RESULTS: The mean flare value was higher on the first postoperative day in both groups. There were no statistically significant between-group differences in flare scores or clinical parameters preoperatively or at any postoperative visit. CONCLUSIONS: No significant difference was observed in inflammation between eyes having HSM PMMA IOL implantation or those having soft hydrophobic acrylic IOL implantation through the same-size incision. This indicates that hydrophobic acrylic and HSM PMMA materials induce the same degree of BAB breakdown after phacoemulsification in eyes of diabetic patients.

Neostigmine added to lidocaine axillary plexus block for postoperative analgesia.

BACKGROUND AND OBJECTIVE: We have assessed the analgesic efficacy and side-effects of neostigmine when added to lidocaine for axillary brachial plexus block, in a prospective, randomized, double-blind, placebo-controlled study. METHODS: We studied 34 ASA I or II patients undergoing elective ambulatory carpal tunnel release. Axillary brachial plexus block was performed using a peripheral nerve stimulator to locate the median nerve. All patients were administered 1.5% lidocaine 450 mg and epinephrine 5 microg mL-1. Patients were allocated randomly to one of two groups. Neostigmine 500 microg was added in group N, and saline 1 mL in group S. RESULTS: The duration of analgesia did not significantly differ between groups [mean (SD)]: 812.5 (456.9) for group S vs. 746.7 (474.1) min for group N (P > 0.05). The need for supplementary analgesia did not significantly differ between groups: 4.4 (1.5) extra doses for group S vs. 3.8 (2.2) extra doses for group N (P > 0.05). Visual analogue pain scores and occurrence of side-effects did not significantly differ between groups. CONCLUSION: Neostigmine does not seem to be of clinical value for peripheral nerve blocks.

Economic assessment of the secondary prevention of ischaemic events with lysine acetylsalicylate.

OBJECTIVE: To analyse the economic benefits, in comparison with placebo, of the secondary prevention of ischaemic stroke and myocardial infarction (MI) with lysine acetylsalicylate (Kardégic) in patients with a history of ischaemic stroke, MI or stable and unstable angina pectoris. DESIGN AND SETTING: This was a modelling study from the perspectives of direct medical costs, the social security system and society in France. METHODS: Efficacy data for the secondary prevention of ischaemic events were derived from the Antiplatelet Trialists' Collaboration meta-analysis on antithrombotics. The rates and costs of ischaemic disease and of serious gastrointestinal adverse affects arising from long term aspirin treatment, as well as the costs of treatment with lysine acetylsalicylate, were taken from published sources, using French data where possible. RESULTS: From the social security perspective, the estimated cost-effectiveness ratios show that the prevention of MI in patients with a history of unstable angina (with a 1-year follow-up) is a cost-saving strategy, with net benefits ranging from $US5703 (1996 prices) per avoided MI for lysine acetylsalicylate 300 mg/day to $US5761 per avoided MI for lysine acetylsalicylate 75 mg/day. The prevention of MI and stroke is also a cost-saving strategy in patients with prior MI [net benefits in a 2-year follow-up (5% discount rate) ranging from $US15 to $US494 per avoided MI and from $US37 to $US1170 per avoided stroke]. This was also true in patients with prior ischaemic stroke (net benefits in a 3-year follow-up ranging from $US610 to $US2082 per avoided MI and from $US176 to $US599 per avoided stroke). Finally, a 4-year follow-up in patients with a history of stable angina pectoris shows that prophylactic treatment with lysine acetylsalicylate is associated with net costs per avoided MI, ranging from $US4375 to $US3608 per avoided event. Sensitivity analysis confirmed that prophylaxis with lysine acetylsalicylate in patients at high risk of cardiovascular and cerebrovascular events results in savings in social security expenditure. CONCLUSIONS: Our results underline the high economic benefit of using lysine acetylsalicylate to prevent secondary ischaemic stroke and MI in patients at high risk of cardiovascular and/or cerebrovascular events, leading to savings for the social security system and society.