Magnetic and in vitro heating properties of implants formed in situ from injectable formulations and containing superparamagnetic iron oxide nanoparticles (SPIONs) embedded in silica microparticles for magnetically induced local hyperthermia

The biological and therapeutic responses to hyperthermia, when it is envisaged as an anti-tumor treatment modality, are complex and variable. Heat delivery plays a critical role and is counteracted by more or less efficient body cooling, which is largely mediated by blood flow. In the case of magnetically mediated modality, the delivery of the magnetic particles, most often superparamagnetic iron oxide nanoparticles (SPIONs), is also critically involved. We focus here on the magnetic characterization of two injectable formulations able to gel in situ and entrap silica microparticles embedding SPIONs. These formulations have previously shown suitable syringeability and intratumoral distribution in vivo. The first formulation is based on alginate, and the second on a poly(ethylene-co-vinyl alcohol) (EVAL). Here we investigated the magnetic properties and heating capacities in an alternating magnetic field (141 kHz, 12 mT) for implants with increasing concentrations of magnetic microparticles. We found that the magnetic properties of the magnetic microparticles were preserved using the formulation and in the wet implant at 37 degrees C, as in vivo. Using two orthogonal methods, a common SLP (20 Wg(-1)) was found after weighting by magnetic microparticle fraction, suggesting that both formulations are able to properly carry the magnetic microparticles in situ while preserving their magnetic properties and heating capacities. (C) 2010 Elsevier B.V. All rights reserved.

Implementation and evaluation of an internet health site for adolescents in Switzerland.

Ciao is a website specifically designed for young people and focuses mainly on health issues. This report presents the process of setting up the site and a first evaluation undertaken by using two self-administered questionnaires administered via the website itself. It suggests that it is possible to provide young people with authoritative health information and to facilitate their access to counseling and health care facilities by having young people use such a website.

Do pornographic websites influence boys' sexual behavior?

Purpose: To compare the sexual behavior of adolescent males who do and do not watch pornographic websites. Methods: This study was presented as a school survey. Data were drawn from the 2002 Swiss Multicenter Adolescent Survey on Health (SMASH02) database, a survey including 7,548 adolescents age 16-20. The setting was post-mandatory schools in Switzerland. A total of 2,891 male students who connected to the internet in the last 30 days were enrolled and distributed into two groups: boys who deliberately watched pornographic websites in the last 30 days (n ¼ 942; 33%) and boys who did not (n ¼ 1,949; 67%). Socio-demographic characteristics; frequency of connection to the internet; sexual behavior parameters (having a girlfriend and if yes, for more or less than 6 months; having had sexual intercourse; age at first sexual intercourse; use of a condom at last sexual intercourse; number of sexual partners; having made a partner pregnant). Results: A logistic regression was performed using STATA 9.2. The only significant socio-demographic variable was having a low socioeconomic status (adjusted odds ratio [AOR] 1.66); no difference was found for age and academic track between the two groups. Boys who watch pornographic websites were also significantly more likely to connect frequently to the internet (one day a week: AOR 1.75; several days a week: AOR 2.36; every day: AOR 3.11), to have had sexual intercourse (AOR 2.06), and to have had their first sexual intercourse before age 15 (AOR 1.48). The stability of the relationship with their girlfriend did not appear to have any influence on the search for pornography on the internet. Conclusions: About one third of boys in our sample report having accessed pornographic websites in the last 30 days, a proportion similar to other studies. Watching such websites increases with the frequency of connection to the internet and seems to be correlated with an earlier sexual activity debut among adolescent males. However, having had first sexual intercourse before age 15 is the only sexual risk behavior that seems to be increased when watching pornographic websites among boys. Further studies should address the causality of this correlation and the factors influencing the search for pornography on the web among boys, in order to explore some new ways of prevention about sexual risk behaviors. Sources of Support: The SMASH02 survey was carried out with the financial support of the Swiss Federal Office of Public Health and the participating cantons.

The impact of pre- and post-natal contexts on immunity, glucocorticoids and oxidative stress resistance in wild and domesticated grey partridges

Genetic background, prenatal and post-natal early-life conditions influence the development of interconnected physiological systems and thereby shape the phenotype. Certain combinations of genotypes and pre- and post-natal conditions may provide higher fitness in a specific environmental context. Here, we investigated how grey partridges Perdix perdix of two strains (wild and domesticated) cope physiologically with pre- and post-natal predictable vs. unpredictable food supply. Food unpredictability occurs frequently in wild environments and requires physiological and behavioural adjustments. Well-orchestrated and efficient physiological systems are presumably more vital in a wild environment as compared to captivity. We thus predicted that wild-strain grey partridges have a stronger immunity, glucocorticoid (GC) stress response and oxidative stress resistance (OSR) than domesticated birds, which have undergone adaptations to captivity. We also predicted that wild-strain birds react more strongly to environmental stimuli and, when faced with harsh prenatal conditions, are better able to prepare their offspring for similarly poor post-natal conditions than birds of domesticated origin. We found that wild-strain offspring were physiologically better prepared for stressful situations as compared to the domesticated strain. They had a high GC stress response and a high OSR when kept under predictable food supply. Wild-strain parents reacted to prenatal unpredictable food supply by lowering their offspring's GC stress response, which potentially lowered GC-induced oxidative pressure. No such pattern was evident in the domesticated birds. Irrespective of strain and prenatal feeding scheme, post-natal unpredictable food supply boosted immune indices, and GC stress response was negatively related to antibody response in females and to mitochondrial superoxide production. Wild-strain grey partridge showed fitness-relevant physiological advantages and appeared to prepare their offspring for the prospective environment. Negative relationships between GC stress response, immunity and oxidative indices imply a pivotal role of an organism's oxidative balance and support the importance of considering multiple physiological systems simultaneously.

To use it or not to use it: differences between adolescent males carrying a weapon and those using it in a fight

Purpose Data indicate that 19% of male adolescents living in Switzerland carried a weapon in the last 12 months. The main objective of this research is to compare the characteristics of male adolescents carrying a weapon and having used it in a fight from those who have carried but not used it in the previous 12 months. Methods Data were drawn from the 2002 Swiss Multicenter Adolescent Survey on Health (SMASH02) data base, a survey including 7,548[3,710 males] in-school adolescents aged 16-20 years in Switzerland. Only males declaring having carried a weapon (N = 711; 19.2% of the sample) were included in the analysis. Three groups were created: those not having used a weapon (WO; N = 538 subjects), those having used a weapon in a fight once or twice (W12; N = 127), and those having used a weapon in a fight 3 or more times (W3+; N = 46). Multinomial logistic regression was performed to compare the 3 groups on individual, family, school, and social factors using WO as the reference category. Analyses were performed with STATA9. Results are presented as relative risk ratios (RRR). Results W12 males were significantly more likely to perceive their puberty as advanced compared to their peers (RRR: 2.1), to be foreign born (RRR: 2.6), to live in an urban environment (RRR: 1.9), to be in vocational school (RRR: 4.7), to have a poor school connectedness (RRR: 1.8), to skip classes (RRR: 2.1) and to quarrel while intoxicated (RRR: 5.3). W3+ males were significantly more likely to be foreign born (RRR: 3.6) and to live in an urban environment (RRR: 2.4), to be current users of illegal drugs other than cannabis (RRR: 3.8) and to quarrel while intoxicated (RRR: 4.1). No differences were found between groups for tobacco, alcohol, or cannabis use. Conclusions Within a national sample of Swiss youth aged 16-20 years, almost one fifth of male adolescents have carried a weapon in the previous 12 months. Nevertheless, most of them (75.7%) have never used a weapon in a fight. Whether they carry a weapon for defense purposes or as a manly behavior remains to be elucidated. However, urban foreign-born adolescents who quarrel while intoxicated are the most at risk of using a weapon in a fight, and therefore culturally-sensitive prevention approaches need to be developed to decrease violence in this specific population of youth. Having school problems or using illegal drugs other than cannabis seem to differentiate between those who use it in a fight occasionally (once or twice) and those who do it more often.

Cannabis use as a means of socialization?: new consumption patterns among heavy users

Purpose: After tobacco and alcohol, cannabis is the most used substance among adolescents in Switzerland. Our aim is to assess whether cannabis use has become an ordinary means of socialization. We hypothesize that cannabis consumption has become a normative, although still illegal, behavior. Methods: As part of a larger qualitative study aimed at assessing new ways [patterns] of cannabis consumption, 16 daily cannabis consumers (11 males) and 2 former heavy consumers (both females), aged 15 to 20 years, participated in interviews and focus groups. Data were transcribed verbatim and analyzed using Atlas.ti qualitative analysis software. Results: Most consumers define the beginning of their consumption as a moment when they made new friends. They commonly use cannabis in group settings, which encourages the belief that all adolescents use cannabis. Thus, cannabis is mainly identified as an everyday social act. Joints are smoked like cigarettes: at all times of the day, during or after school or work with peers, often starting at lunch break, and mostly in public places. Friends offer a joint in a group setting, much like beer in a bar, as a means of making contact. Consumption invariably increases while socializing on vacation: "During vacation, we smoke up to 10-15 joints a day; at the end we're just dead." Additionally, in order to obtain cannabis, consumers have to be part of the right networks; they generally have several dealers to assure their supply, buy and sell themselves, or practice group-buying. As a result, all friends or acquaintances of consumers are themselves cannabis users. For instance, 4 boys, who say they are best friends, always smoke together and that, in order to quit, "All four of us should say to ourselves, 'Okay, now, let's all stop smoking'. That would be the only solution. . .but it would be impossible!" The 2 former consumers state that when they started using cannabis, "I found myself little by little in a vicious circle where I saw only people who also smoked". When they quit, they separated from their group of friends: "Either you make new friends who don't smoke or you smoke." Conclusions: Discussions with consumers demonstrate a normative facet of cannabis consumption as part of teenage socialization. Consequently, cannabis consumers develop a significant dependency since a majority of their friends use cannabis and their consumption involves most of their daily social life. Our study highlights the need for clear messages about the harmful aspects of using this substance while also suggesting that cessation efforts should include helping users separate from their consumption milieu. Sources of Support: Dept. of Public Health of the canton of Vaud.

Macroeconomic modeling for monetary policy evaluation

We describe some of the main features of the recent vintage macroeconomic models used for monetary policy evaluation. We point to some of the key differences with respect to the earlier generation ofmacro models, and highlight the insights for policy that these new frameworks have to offer. Our discussion emphasizes two key aspects of the new models: the significant role of expectations of future policy actions in the monetary transmission mechanism, and the importance for the central bank of tracking of the flexible price equilibrium values of the natural levels of output and the real interest rate. We argue that both features have important implications for the conduct of monetary policy.

Fecundidad parcial de Caballa del Perú (Scomber japonicus peruanus)

Un nuevo método, el conteo de ovocitos hidratados, se aplica por primera vez para determinar la fecundidad de la caballa peruana (Scomber Japonicus peruanus) . En febrero de 1985, la fecundidad relativa media fue 278 huevos por gramo de hembra y la fecundidad parcial media de la muestra fue 78,174 huevos por hembra. Se muestra que la caballa del Perú es un desovador múltiple.

Intravenous thrombolysis in patients with stroke attributable to small artery occlusion.

BACKGROUND: Intravenous thrombolysis (IVT) for stroke seems to be beneficial independent of the underlying etiology. Recent observations raised concern that IVT might cause harm in patients with strokes attributable to small artery occlusion (SAO). OBJECTIVE: The safety of IVT in SAO-patients is addressed in this study. METHODS: We used the Swiss IVT databank to compare outcome and complications of IVT-treated SAO-patients with IVT-treated patients with other etiologies (non-SAO-patients). Main outcome and complication measures were independence (modified Rankin scale <or=2) at 3 months, intracranial hemorrhage (ICH), and recurrent ischaemic stroke. RESULTS: Sixty-five (6.2%) of 1048 IVT-treated patients had SAO. Amongst SAO-patients, 1.5% (1/65) patients died, compared to 11.2% (110/983) in the non-SAO-group (P = 0.014). SAO-patients reached independence more often than non-SAO-patients (75.4% versus 58.9%; OR 2.14 (95% CI 1.20-3.81; P = 0.001). This association became insignificant after adjustment for age, gender, and stroke severity (OR 1.41 95% CI 0.713-2.788; P = 0.32). Glucose level and (to some degree) stroke severity but not age predicted 3-month-independence in IVT-treated SAO-patients. ICHs (all/symptomatic) were similar in SAO- (12.3%/4.6%) and non-SAO-patients (13.4%/5.3%; P > 0.8). Fatal ICH occurred in 3.3% of the non-SAO-patients but none amongst SAO-patients. Ischaemic stroke within 3 months after IVT reoccurred in 1.5% of SAO-patients and in 2.3% of non-SAO-patients (P = 0.68). CONCLUSION: IVT-treated SAO-patients died less often and reached independence more often than IVT-treated non-SAO-patients. However, the variable 'SAO' was a dependent rather than an independent outcome predictor. The absence of an excess in ICH indicates that IVT seems not to be harmful in SAO-patients.

« Grand livre n° 2 du vaisseau le Superbe, 1774-1775 ».

Provient des Archives nationales, MM. 1054

Daily smoking as a marker of weight control practices among female adolescents

Purpose: There is evidence indicating that adolescent females smoke as a way to control weight. The aim of our research is to assess whether daily smoking is a marker for weight control practices among adolescent females. Methods: Data were drawn from the 2002 Swiss Multicenter Adolescent Survey on Health (SMASH02) data base, a survey including 7,548 [3,838 females] in-school adolescents aged 16-20 years in Switzerland. Among females self-reporting BMI (N _ 3,761), two groups were drawn: daily smokers (DS, N _ 1,273) included all those smoking at least 1 cigarette/day and never smokers (NS, N _ 1,888) included all those having never smoked. Former (N _ 177) and occasional (N _ 423) smokers were not included. Groups were compared on weight control practices (being on a diet, self-induced vomiting, use of doctor-prescribed or over-the-counter appetite suppressors) controlling for possible confounding variables (age, BMI, feeling fat, body image, use of other substances, depression, sport practice, academic track and perceived advanced puberty). Analyses were performed with STATA 9. Bivariate analyses are presented as point-prevalence and multivariate analysis (using logistic regression) are presented as adjusted odds ratio (AOR) and [95% confidence interval]. Results: In the bivariate analysis, DS females were significantly more likely (p _ 0.001) than NS to be on a diet (DS: 33.2%, NS: 22.2%), to self-induce vomiting (DS: 9.0%, NS: 3.3%), and to use doctor prescribed (DS: 2.3%, NS: 0.9%) or over-the-counter (DS: 3.2%, NS: 1.2%) appetite suppressors. In the multivariate analysis, DS females were more likely than NS to be on a diet (AOR: 1.40 [1.17/1.68]), to self-induce vomiting (AOR: 2.07 [1.45/2.97]), and to use doctor-prescribed appetite suppressors (AOR: 1.99 [1.00/ 3.96]). Conclusions: Weight control practices are more frequent among female daily smokers than among never smokers. This finding seems to confirm cigarette smoking as a way to control weight among adolescent females. Health professionals should inquire adolescent female smokers about weight control practices, and this association must be kept in mind when discussing tobacco cessation options with adolescent females. Sources of Support: The SMASH02 survey was funded by the Swiss Federal Office of Public Health and the participating cantons.

Is cannabis use a significant exposition to nicotine?

Purpose: Young cannabis users are at increased risk for cigarette initiation and later progression to nicotine dependence. The present study assesses to which extent cannabis users are exposed to nicotine through mulling, a widespread process consisting of mixing tobacco to cannabis for its consumption. Methods: Data are issued from an ongoing observational study taking place in Switzerland. A total of 267 eligible participants (mean age 19 years, 46.4% males) completed an anonymous self-administered questionnaire on their tobacco and cannabis intake in the previous 5 days. They also provided a urine sample that was blindly analyzed for cotinine (a key metabolite of nicotine) using liquid-chromatography coupled mass-spectrometry. After the exclusion of cannabis users not having smoked at least one joint/blunt in which tobacco had been mixed (n _ 2), and participants reporting other sources of nicotine exposition than cigarettes or mulling (n _37), four groups were created: cannabis and cigarette abstainers (ABS, n_ 69), cannabis only smokers (CAS; n _ 33), cigarette only smokers (CIS; n _ 62); and cannabis and cigarette smokers (CCS, n _ 64). Cotinine measures of CAS were compared to those of ABS, CIS and CCS. All comparisons were performed using ANCOVA, controlling for age, gender, ethnicity, BMI and environmental exposure to cigarette smoke in the past month (at home, in school/at work, in social settings). The number of mixed joints/blunts smoked in the previous 5 days was additionally taken into account when comparing CAS to CCS. Cotinine values (ng/ml) are reported as means with 95% confidence interval (95% CI). Results: In the previous 5 days, CAS had smoked on average 10 mixed joints/blunts, CIS 30 cigarettes, and CCS 8 mixed joints/ blunts and 41 cigarettes. Cotinine levels of participants considerably differed between groups. The lowest measure was found among ABS (3.2 [0.5-5.9]), followed in growing order by CAS (294.6 [157.1-432.0]), CIS (362.8 [258.4-467.3]), and CCS (649.9 [500.7-799.2]). In the multivariate analysis, cotinine levels of CAS were significantly higher than those of ABS (p _.001), lower than those of CCS (p _ .003), but did not differ from levels of CIS (p _ .384). Conclusions: Our study reveals cannabis users to be significantly exposed to nicotine through mulling, even after controlling for several possible confounders such as environmental exposure to cigarette smoke. Utmost, mixing tobacco to Poster cannabis can result in a substantial nicotine exposition as cotinine levels from cannabis only smokers were as high as those of moderate cigarette smokers. Our findings also suggest that mulling is adding up to the already important nicotine exposition of cigarettes smokers. Because of the addictiveness of nicotine, mulling should be part of a comprehensive assessment of substance use among adolescents and young adults, especially when supporting their cannabis and cigarette quitting attempts. Sources of Support: This study was funded by the Public Health Service of the Canton de Vaud. Dr. BÊlanger's contribution was possible through grants from the Royal College of Physicians and Surgeons of Canada, the CHUQ/CMDP Foundation and the Laval University McLaughlin program, QuÊbec, Canada.