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971.
Mescaline (3,4,5-trimethoxyphenylethylamine) is an hallucinogenic psychoactive substance present in several species of cacti. Mescaline has a documented use dating back 5700 years. In more recent years, the interest in hallucinogenic designer drugs such as ecstasy has also triggered interest in the naturally occurring mescaline. This study was undertaken to develop a liquid chromatography-tandem mass spectrometry (LC-MS-MS) method for the screening and confirmation of mescaline in human urine samples and to apply this method to routine testing in patient samples. For the screening procedure, chromatographic separation was achieved on a 5-microm HyPURITY C(18) column, using a methanol gradient in ammonium acetate buffer. The MS-MS analysis was performed using selected reaction monitoring; the transitions monitored were m/z 212.3 --> m/z 180.3 for mescaline and m/z 221.3 --> m/z 186.3 for the deuterated internal standard (mescaline-d(9)). The detection limit for mescaline in urine matrix was 3-5 microg/L, the upper limit of quantification was 10,000 microg/L, and the total coefficient of variation for spiked samples containing 10 to 1025 microg/L was < 8.5%. The confirmation procedure included a sample clean-up by solid-phase extraction on a C(18) cartridge, and one extra transition for mescaline (m/z 212.3 --> m/z 195.2) was monitored. The LC-MS-MS method was found to be sensitive and specific for the routine detection of mescaline in urine. Among 462 urine samples collected from young people with alcohol or drug problems, 32% were positive for illicit drugs, but none for mescaline. 相似文献
972.
Leonoor Wijnans Coralie Lecomte Corinne de Vries Daniel Weibel Cormac Sammon Anders Hviid Henrik Svanström Ditte Mølgaard-Nielsen Harald Heijbel Lisen Arnheim Dahlström Jonas Hallgren Par Sparen Poul Jennum Mees Mosseveld Martijn Schuemie Nicoline van der Maas Markku Partinen Silvana Romio Francesco Trotta Carmela Santuccio Angelo Menna Giuseppe Plazzi Keivan Kaveh Moghadam Salvatore Ferro Gert Jan Lammers Sebastiaan Overeem Kari Johansen Piotr Kramarz Jan Bonhoeffer Miriam C.J.M. Sturkenboom 《Vaccine》2013
Background
In August 2010 reports of a possible association between exposure to AS03 adjuvanted pandemic A(H1N1)pdm09 vaccine and occurrence of narcolepsy in children and adolescents emerged in Sweden and Finland. In response to this signal, the background rates of narcolepsy in Europe were assessed to rapidly provide information for signal verification.Methods
We used a dynamic retrospective cohort study to assess the narcolepsy diagnosis rates during the period 2000–2010 using large linked automated health care databases in six countries: Denmark, Finland, Italy, the Netherlands, Sweden and the United Kingdom.Results
Overall, 2608 narcolepsy cases were identified in almost 280 million person years (PY) of follow up. The pooled incidence rate was 0.93 (95% CI: 0. 90–0.97) per 100,000 PY. There were peaks between 15 and 30 year of age (women > men) and around 60 years of age. In the age group 5–19 years olds rates were increased after the start of pandemic vaccination compared to the period before the start of campaigns, with rate ratios (RR) of 1.9 (95% CI: 1.1–3.1) in Denmark, 6.4 (95% CI: 4.2–9.7) in Finland and 7.5 (95% CI: 5.2–10.7) in Sweden. Cases verification in the Netherlands had a significant effect on the pattern of incidence over time.Conclusions
The results of this incidence study provided useful information for signal verification on a population level. The safety signal of increased narcolepsy diagnoses following the start of the pandemic vaccination campaign as observed in Sweden and Finland could be observed with this approach. An increase in narcolepsy diagnoses was not observed in other countries, where vaccination coverage was low in the affected age group, or did not follow influenza A(H1N1)pdm09 vaccination. Patient level analyses in these countries are being conducted to verify the signal in more detail. 相似文献973.
Background
General practitioners often diverge from clinical guidelines regarding spine radiography. This study aimed to identify and describe A) factors general practitioners consider may affect their decisions about ordering plain radiography for back pain and B) barriers to guideline adherence suggested by such factors. 相似文献974.
Hallmans G Zhang JX Lundin E Stattin P Johansson A Johansson I Hultén K Winkvist A Aman P Lenner P Adlercreutz H 《The Proceedings of the Nutrition Society》2003,62(1):193-199
Rye bran contains a high content not only of dietary fibre, but also of plant lignans and other bioactive compounds in the so-called dietary fibre complex. Blood concentrations of lignans such as enterolactone have been used as biomarkers of intake of lignan-rich plant food. At present,evidence from studies in human subjects does not warrant the conclusion that rye, whole grains orphyto-oestrogens protect against cancer. Some studies, however, have pointed in that direction,especially in relation to cancers of the upper digestive tract. A number of prospective epidemiological studies have clearly shown a protective effect of wholegrain cereals against myocardial infarctions. A corresponding protective effect against diabetes and ischaemic stroke(brain infarct) has also been demonstrated. It seems reasonable to assume that these protective effects are associated with one or more factors in the dietary fibre complex. 相似文献
975.
Lindbäck H Lindbäck J Tegnell A Janzon R Vene S Ekdahl K 《Emerging infectious diseases》2003,9(4):438-442
Dengue fever (DF) has become common in western travelers to the tropics. To improve the basis for travel advice, risk factors and dengue manifestations were assessed in 107 Swedish patients for whom DF was diagnosed after return from travel in 1998 and 1999. Patient data were compared with data on a sample of all Swedish travelers to dengue-endemic countries in the same years. Only three of the patients had received pretravel advice concerning DF from their physicians. Hemorrhagic manifestations were common (21 of 74 patients) but caused no deaths. Risk factors for a DF diagnosis were travel to the Malay Peninsula (odds ratio [OR] 4.95; confidence interval [CI] 2.92 to 8.46), age 15-29 years (OR 3.03; CI 1.87 to 4.92), and travel duration >25 days (OR 8.75; CI 4.79 to 16.06). Pretravel advice should be given to all travelers to DF-endemic areas, but young persons traveling to southern and Southeast Asia for >3 weeks (who constituted 31% of the patients in our study) may be more likely to benefit by adhering to it. 相似文献
976.
Agartz I Brag S Franck J Hammarberg A Okugawa G Svinhufvud K Bergman H 《Alcohol and alcoholism (Oxford, Oxfordshire)》2003,38(1):71-78
AIMS: The brain volume of chronic drinkers is known to partially recover with abstinence from alcohol. To investigate the relative contribution of grey and white brain matter to this process, magnetic resonance imaging and brain tissue segmentation was used to study brain tissue in acute alcohol withdrawal and abstinence in seven alcohol-dependent men. METHODS: The patients were studied on three occasions; within 48 h after the last drink and approximately one month and two and a half months later. Total brain tissue class volumes [grey matter (GM) and white matter (WM) and cerebrospinal fluid (CSF)] were measured. Eleven healthy volunteers were scanned twice to serve as a control group. The alcohol-dependent patients were investigated with regard to drinking variables, neuropsychological performance and blood biochemistry. RESULTS: In the alcohol-dependent patients, intracranial volume and total GM volume did not change between scan occasions, except in a single patient who demonstrated a GM increase of 4.8% (4.2% relative volume) between scans 2 and 3. For all patients, the increase in total WM volume ranged between 1.9 and 22.4% (absolute volumes) and 2.1 and 21.2% (relative volumes). Between scans 2 and 3, the increase in total WM volume ranged between 0.3 and 13.2% (absolute volumes), and between 1.5 and 14.0% (relative volumes). One patient resumed drinking and was investigated a second time during acute withdrawal. In this patient, the measured decrease of 8.1 and 8.5% of absolute and relative WM volumes corresponded to the size of the volume increase between scans 1 and 2. CSF, GM and WM volumes in the healthy subjects were constant over time. CONCLUSIONS: The results demonstrate that changes in brain volume during short-term abstinence in chronic alcohol-dependent patients are confined to the WM. The time limit of WM volume restitution is variable and continues longer than 3 weeks after withdrawal. 相似文献
977.
Height and body mass index in relation to total mortality 总被引:3,自引:0,他引:3
BACKGROUND: The relation between body mass index (BMI) and mortality is not clear in the literature. An inverse relation between height and mortality has been suggested. We explore these relations in a very large cohort in Norway. METHODS: We studied two million men and women, age 20-74 years, who were measured during 1963-2000. These persons were followed for an average of 22.1 years. We used Cox proportional hazard models in the analyses. Also, the optimal BMI (the BMI at the time of measurement that was subsequently related to the lowest mortality) was estimated. RESULTS: Over the study period, 723,000 deaths were registered. The relative risk of death by BMI showed a J- or U-shaped curve, with the lowest rates of death at BMI between 22.5 and 25.0. In men, the optimal BMI increased from 21.6 when measured at age 20-29 to 24.0 when measured at age 70-74. In women, the optimal BMI was consistently higher, increasing from 22.2 to 25.7. Mortality decreased with increased height in men; in women, mortality decreased with height only up to heights of about 160-164 cm and then increased among the tallest women. CONCLUSIONS: The relation between BMI and mortality was J- or U-shaped, with the "optimal" BMI varying by age and sex. Height was inversely related to mortality in men and in women up to a height of 165 cm. 相似文献
978.
Stefan Kaspers Michael B. Ranke Donald Han Jane Loftus Hartmut Wollmann Anders Lindberg Mathieu Roelants Joris Kleintjens 《Applied health economics and health policy》2013,11(3):237-249
Background
Response to growth hormone (GH) therapy may vary between individual patients. Therefore the use of GH in children should be closely monitored to avoid over, under, or ineffective treatment regimens. The treatment response can be evaluated using growth prediction models. In an effort to improve the accuracy of these prediction models, Ranke et al. (J Clin Endocrinol Metab 95(3):1229–37) proposed a novel ‘data-driven’ approach based on a quantitative analysis of a large cohort of patients from the Pfizer International Growth Database (KIGS) treated with Genotropin (human growth hormone). This model allows physicians to predict and evaluate the level of growth response and responsiveness for their patients so they can adapt treatment accordingly. By comparing the actually observed and the predicted growth response the ability of an individual to respond to GH (responsiveness) can be estimated and further treatment can be adapted accordinglyObjective
To determine the potential population level reduction in the amount of GH used and impact on height outcome of using this data-driven approach to guide treatment decisions, compared to conventional, ‘experience-based’ GH treatment in prepubertal patients with growth hormone deficiency (GHD) or Turner syndrome (TS).Methods
A model was developed to study the height outcome and the total amount of GH used in the presence or absence of data-driven treatment decisions. The proportion of patients for whom height outcome could be improved or GH use could be reduced (i.e. for low compliance, high or low responder) was estimated using the KIGS cohort. The analysis assumed that this segmentation allows physicians to tailor dosage to the individual patient’s needs or even to discontinue therapy when it is not effective. The analysis used a 4-year time horizon, with Germany as an example country, but results are extendable to other countries. Only the total amount of GH used was included, and effects were defined as the height outcome after 4 years.Results
The analysis estimated that an evidence-driven approach may reduce the total amount of GH utilized by 7.0 % over 4 years for the treatment of short stature in prepubertal patients with GHD and TS in Germany. Despite the reduction in drug use the average growth outcomes remained unaffected with the new treatment approach. Univariate and probabilistic sensitivity analyses showed that the results are robust.Conclusions
Our analysis showed that using a data-driven approach to guide treatment decisions for children with GHD or TS is estimated to result in efficiencies in the amount of GH used, without reducing the average growth in the population. 相似文献979.
Thomsen M Fink-Jensen A Woldbye DP Wörtwein G Sager TN Holm R Pepe LM Caine SB 《Psychopharmacology》2008,201(1):43-53
Rationale Dopamine D2-like partial agonists such as aripiprazole have received some attention as potential pharmacotherapies for the
treatment of psychostimulant addiction. However, the preclinical evaluations so far have focused on acute effects of aripiprazole.
Objectives We tested the hypothesis that aripiprazole, both as acute and as chronic treatment, would preferentially decrease cocaine
self-administration while sparing behavior maintained by a natural reinforcer, resulting in a shift in the allocation of behavior
from cocaine-taking towards the alternative reinforcer.
Materials and methods Rats were trained to self-administer intravenous cocaine in a concurrent choice procedure, with a palatable food as the competing
reinforcer, under a fixed ratio (FR) 1 FR 5 chain schedule. Aripiprazole was then administered as continuous infusion by osmotic
minipumps for 5 days, during which performance in the choice procedure was assessed daily.
Results An intermediate dose of aripiprazole decreased cocaine self-administration and shifted the cocaine choice curve to the right
as an acute treatment. However, as a chronic treatment, aripiprazole failed to decrease cocaine self-administration or cocaine
choice, despite a dose-dependent decrease in overall response rates and food-maintained behavior.
Conclusions Our results confirm and extend earlier findings and indicate that acute administration of aripiprazole can decrease cocaine
self-administration. However, based on the present data, chronic treatment with aripiprazole does not show much promise as
a potential pharmacotherapy for cocaine addiction. Both acute and chronic treatment data are in agreement with published clinical
findings, suggesting that the concurrent choice procedure in rats has predictive validity of efficacy in humans. 相似文献
980.
Inhaled corticosteroid (ICS) therapy is central to the long-term management of asthma and is extensively used in the management of chronic obstructive pulmonary disease (COPD). While administration via inhalation limits systemic exposure compared with oral or injected corticosteroids and, therefore, the risk of systemic corticosteroid-related adverse effects, concerns over the long-term safety of ICS persist. The assessment of the long-term effects of ICS therapy requires considerable research effort over years or even decades. Surrogate markers/predictors for clinical endpoints such as adrenal crisis, reduced final height and fractures have been identified for use in relatively short-term studies. However, the predictive value of such markers remains questionable.Inhaled budesonide has been available since the early 1980s and there is a considerable evidence base investigating the safety of this agent. To assess the long-term safety of inhaled budesonide therapy in terms of the actual incidence of the clinical endpoints adrenal crisis/insufficiency, reduced final height, fractures and pregnancy complications, we undertook a review of the scientific literature. The external databases BIOSIS, Cochrane Central Register of Controlled Trials, Current Contents, EMBASE, International Pharmaceutical Abstracts and MEDLINE were searched, in addition to AstraZeneca's internal product literature database Planet, up to 29 February 2008. Only original articles of epidemiological studies, national surveys, clinical trials and case reports concerning inhaled budesonide were included.Eight surveys of adrenal crisis were found. The only survey with specified criteria for diagnosis involved 2912 paediatricians and endocrinologists and revealed 33 patients with adrenal crisis associated with ICS therapy; only one patient used budesonide (in co-treatment with fluticasone propionate). In addition, 14 case reports of adrenal crisis in budesonide-treated patients were found. In only two of these, budesonide was used at recommended doses and in the absence of interacting medication.Three retrospective studies and one prospective study assessing final height were found. None of them showed any reduced final height in patients receiving inhaled budesonide during childhood or adolescence.Seventeen epidemiological studies investigating the risk of fractures were found. When adjusting for confounding factors, they did not provide any unequivocal data for an increased fracture risk with budesonide. Four prospective placebo-controlled clinical trials of 2-6 years duration with inhaled budesonide in patients with asthma or COPD were found. None of the studies identified any association between inhaled budesonide and increased risk for fractures.Four studies using data from the Swedish birth and health registries showed there was no increased risk for congenital malformations, cardiovascular defects, decreased gestational age, birth weight or birth length among infants born to women using inhaled budesonide during pregnancy compared with the general population. This was confirmed by five observational studies in Australia, Canada, Hungary, Japan and the US. Similarly, one randomized clinical trial comparing pregnancy outcomes among asthma patients receiving inhaled budesonide or placebo did not demonstrate any difference in outcome of pregnancy.In summary, based on 25 years of experience with different doses and in different populations, inhaled budesonide therapy only in very rare cases appears to be associated with an increased risk of adrenal crisis, reduction in final height, increases in the number of fractures or complications during pregnancy. 相似文献