400 kHz repetition rate THz-TDS with 24†mW of average power driven by a compact industrial Yb-laser.

We demonstrate a high average power terahertz time-domain spectroscopy (THZ-TDS) set-up based on optical rectification in the tilted-pulse front geometry in lithium niobate at room temperature, driven by a commercial, industrial femtosecond-laser operating with flexible repetition rate between 40 kHz - 400 kHz. The driving laser provides a pulse energy of 41 µJ for all repetition rates, at a pulse duration of 310 fs, allowing us to explore repetition rate dependent effects in our TDS. At the maximum repetition rate of 400 kHz, up to 16.5 W of average power are available to drive our THz source, resulting in a maximum of 24 mW of THz average power with a conversion efficiency of ∼ 0.15% and electric field strength of several tens of kV/cm. At the other available lower repetition rates, we show that the pulse strength and bandwidth of our TDS is unchanged, showing that the THz generation is not affected by thermal effects in this average power region of several tens of watts. The resulting combination of high electric field strength with flexible and high repetition rate is very attractive for spectroscopy, in particular since the system is driven by an industrial and compact laser without the need for external compressors or other specialized pulse manipulation.

Control of the acoustic waves generated by intense laser filamentation in water.

Experiments and simulations are performed to study filamentation and generation of acoustic waves in water by loosely focused multi-millijoules laser pulses. When the laser pulse duration is increased from femtosecond to nanosecond duration, a transition is observed from a filamentary propagation with extended and low energy density deposition to a localized breakdown, related to high energy density deposition. The transition suggests that Kerr self-focusing plays a major role in the beam propagation dynamics. As a result, the shape, the amplitude and the spectrum of the resulting pressure wave present a strong dependence on the laser pulse duration.

IGF-II promotes neuroprotection and neuroplasticity recovery in a long-lasting model of oxidative damage induced by glucocorticoids.

Insulin-like growth factor-II (IGF-II) is a naturally occurring hormone that exerts neurotrophic and neuroprotective properties in a wide range of neurodegenerative diseases and ageing. Accumulating evidence suggests that the effects of IGF-II in the brain may be explained by its binding to the specific transmembrane receptor, IGFII/M6P receptor (IGF-IIR). However, relatively little is known regarding the role of IGF-II through IGF-IIR in neuroprotection. Here, using adult cortical neuronal cultures, we investigated whether IGF-II exhibits long-term antioxidant effects and neuroprotection at the synaptic level after oxidative damage induced by high and transient levels of corticosterone (CORT). Furthermore, the involvement of the IGF-IIR was also studied to elucidate its role in the neuroprotective actions of IGF-II. We found that neurons treated with IGF-II after CORT incubation showed reduced oxidative stress damage and recovered antioxidant status (normalized total antioxidant status, lipid hydroperoxides and NAD(P) H:quinone oxidoreductase activity). Similar results were obtained when mitochondria function was analysed (cytochrome c oxidase activity, mitochondrial membrane potential and subcellular mitochondrial distribution). Furthermore, neuronal impairment and degeneration were also assessed (synaptophysin and PSD-95 expression, presynaptic function and FluoroJade B® stain). IGF-II was also able to recover the long-lasting neuronal cell damage. Finally, the effects of IGF-II were not blocked by an IGF-IR antagonist, suggesting the involvement of IGF-IIR. Altogether these results suggest that, in or model, IGF-II through IGF-IIR is able to revert the oxidative damage induced by CORT. In accordance with the neuroprotective role of the IGF-II/IGF-IIR reported in our study, pharmacotherapy approaches targeting this pathway may be useful for the treatment of diseases associated with cognitive deficits (i.e., neurodegenerative disorders, depression, etc.).

[Potentially inappropriate prescriptions for the elderly: a study of health insurance reimbursements in Southeastern France]. / Prescriptions médicamenteuses potentiellement inadaptées chez les personnes âgées : une étude en Provence-Alpes-Côte d'Azur à partir des données de remboursements de l'Assurance maladie.

BACKGROUND: This study conducted in the region of Provence-Alpes-Côte d'Azur (PACA) sought to assess the feasibility of constructing and using indicators of potentially inappropriate prescriptions for the elderly from health insurance reimbursement data. We present and discuss different indicators of inappropriate prescriptions for people aged 70 years or older (at-risk prescriptions, dangerous or at-risk coprescriptions, absence of necessary coprescriptions) and reports their prevalence in PACA. METHODS: The indicators were constructed from the French list of inappropriate prescriptions, national agency guidelines, and the advice of experts in the field. The indicators selected were applied to the databases of the PACA Salaried Workers' Health Insurance Fund for 2008 for all recipients aged 70 years or older and compared according to age, sex, chronic disease status, and, after standardization for age and sex, according to district of residence. RESULTS: In January 2009, 500,904 recipients aged 70 years or older were identified in the data base of the Salaried Workers' Health Insurance Fund, 60.8% of whom were women and 52.1% of whom had approved coverage for a chronic disease. The potentially inappropriate prescriptions most frequently observed here, in decreasing order, were: prescription of an NSAID without the coprescription of gastric protection (28.1%); long-term benzodiazepine treatment (21.5%); prescription of long half-life benzodiazepine (14.9%), and long-term treatment with NSAIDs (11.6%). Overall, the prevalence of each increased significantly with age and was higher among women and people with chronic diseases. Significant variations were also observed between the different districts of PACA. CONCLUSION: Our results confirm that a substantial proportion of elderly people receive potentially inappropriate prescriptions. They also suggest that health insurance reimbursement data could be used in some prescription domains for monitoring trends in the potentially inappropriate prescriptions in the populations of various territories, provided that specific limitations are considered.

Kidney failure after heart transplantation.

BACKGROUND AND PURPOSE: Heart transplantation is a procedure with a high mortality rate. Altered kidney function (AKF) after a heart transplant is common. The purpose of this study was to determine the incidence of and associated factors for renal dysfunction among patients who underwent heart transplantation in our hospital between January 2006 and November 2008. PATIENTS AND METHODS: This retrospective observational study was performed on all patients receiving a heart transplant between January 1, 2006 and November 15, 2008. The following variables were recorded: patient comorbidities, indication, presurgical urea and creatinine levels, donor variables, surgical procedure, and postoperative features. RESULTS: A total of 54 heart transplantations were performed with 68.5% of patients being male. The average age at transplant was 49.52 years (±13.45 y) and the mean weight 72.5 kg (±14.8 kg). Overall mortality was 28.30%. Of the 54 patients, 70.4% showed AKF during the first week after transplantation; 30.61% were in stage III according to the Acute Kidney Injury classification. There were no statistically significant differences between the group of patients with versus without renal failure, except for the extracorporeal surgery time, which was significantly longer among those patients who had AKF, and glycemia, which was also higher in the immediate postoperative period. Analysis of patient mortality showed no significant differences for the patients with AKF (80% vs 68.4%; P=31). CONCLUSIONS: The rate of acute kidney failure was high (70.4%), as was the use of chronic renal replacement therapy (28.85%), but it decreased considerably when followed over time.

[Impact of the estimation of the medically insured population on the pharmacological prevalence of diabetes at the regional and small area level]. / Impact de l'estimation de la population affiliée à l'assurance-maladie sur le calcul de la prévalence pharmacologique du diabète à l'échelle régionale et territoriale.

BACKGROUND: Data derived from Health Insurance databases are very useful for health observation. These data are however still underused, particularly for small local areas. This may be partly explained by the lack of reliable data on the number of insured people. Recent simplification of the Répertoire national interrégimes de l'assurance-maladie (RNIAM) indicator (French register of health insurance) gives the opportunity to improve the usefulness of these databases. This indicator specifies the beneficiaries' status towards the General Health Insurance Fund. This study aimed to select the population of beneficiaries, which could be most adequately used to calculate health indicators based on these data. METHODS: Data were collected from the outpatient database of the Southeastern France General Health Fund. We compared beneficiaries' characteristics according to the RNIAM indicator, calculated the annual unadjusted and age-adjusted regional and local prevalence of diabetes mellitus in two different populations: the whole initial beneficiaries database, and the population of "effective" beneficiaries (persons whose reimbursements were effectively managed by the General Health Insurance). RESULTS: The initial database included 4,817,871 beneficiaries. Almost 80% were in the "effective" population, 14% had left the General Health Insurance, or Southeastern France, and 4% were doubles. The annual unadjusted prevalence of diabetes mellitus was 3.31% in the initial database, and more than 20% higher when calculated among "effective" beneficiaries. Impact on aged-adjusted prevalence was less important (+9% at regional level), but the increase varied from 6 to 42% for the small local areas. Impact was much higher on age and gender specific rates. CONCLUSION: When Health Insurance databases are used to calculate health indicators at various geographical levels, only "effective" beneficiaries should be selected. The methodology for determining health indicators might be improved by updating databases (e.g. the date of the RNIAM indicator last update should be added).

Application of the McCluskey Index to predict blood product requirements during liver transplantation.

BACKGROUND: A recent study proposed a risk index (McCluskey index) based on 7 parameters to identify the transfusion needs of patients during surgery and in the first 24 hours postoperation. The initial objective of our study was to validate this predictor for blood product transfusions. PATIENTS AND METHODS: We undertook a retrospective, observational study of all liver transplant patients between January 1, 2005 and December 31, 2006. The following variables were recorded for each patient: age, gender, patient comorbidity, biochemical values prior to liver transplantation, and transfusion needs. RESULTS: Comparing the transfusion needs of those patients with scores <5 with those of scores >/=5, we observed significant differences in terms of the use of red blood cell concentrates, plasma, and platelets, both during the first 24 hours and in the total number. The index sensitivity was 80% (95% confidence interval [CI]: 71.23-88.76), with a specificity of 84.21% (95% CI: 67.81-100), where the positive predictive value was 95.52% (95% CI: 90.57-100.4) and the negative predictive value was 50% (95% CI: 32.67-67.32). CONCLUSION: The McCluskey index showed sufficient sensitivity and specificity to predict which patients will require a massive transfusion.

Active coping style is associated with natural killer cell cytotoxicity in asymptomatic HIV-1 seropositive homosexual men.

The aim of this study was to examine the hypothesis that a psychosocial model was associated with natural killer cell cytotoxicity (NKCC) in HIV-1 infection. A sample of 62 HIV-1 seropositive homosexual men at CDC stages II and III were given a psychosocial battery assessing life stressors, social support, and coping style. A regression model quantifying these variables along with control variables for alcohol use, substance use and nutritional status was estimated. Active coping style was directly and positively associated with NKCC, and trends toward a negative relationship of life stressors and a buffering effect of social support on lives stressors were also observed. The results suggest that (1) control variables should be included with psychosocial models and that (2) psychosocial factors, especially active coping, may have a deterrent effect on loss of NK cell function. Active coping style may merit a specific focus in future research of life stressors and the immune system.

A stress-moderator model of distress in early HIV-1 infection: concurrent analysis of life events, hardiness and social support.

A stress moderator framework was employed to investigate the relationship of negative life events, hardiness and social support to psychological distress among 67 asymptomatic HIV-1 seropositive gay males. Both main effects and stress moderator (interaction) models were evaluated. Main effects were found for negative life events and social support but not hardiness (either as commitment or overall hardiness); no moderator effects emerged. Results were the same whether events were quantified as negative impact or as number of events, and were in the predicted direction--life events associated with greater distress, social support with less distress. The present study replicates for early HIV-1 infection findings obtained in non-HIV-infected samples about the influence on psychological distress of negative life events and social support. Methodological limitations, possible explanations for the absence of stress moderator effects, and clinical implications of the findings are discussed.