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181.
OBJECTIVE: To investigate the relationship between overweight and obesity, and mental health problems in Australian 4- to 5-year-old children. METHODS: The study used data from wave 1 (2004) of the Longitudinal Study of Australian Children (LSAC). The participants were 4983 4- to 5-year-old children (2537 boys and 2446 girls) with a mean age of 56.9 months (standard deviation 2.6 months; range 51-67 months). Children were classified as nonoverweight, overweight, and obese on the basis of International Obesity Task Force definitions. Mental health problems were assessed by the Strengths and Difficulties Questionnaire (SDQ) completed by parents and teachers. RESULTS: Although obese 4- to 5-year-old boys had more mental health problems than nonoverweight boys, differences between the groups were small and substantially reduced when analyses controlled for children's sociodemographic characteristics. Parents reported that overweight/obese girls had more peer problems, whereas teachers reported they had more conduct problems. Children in all weight groups had mean scores within the normal range of scores on all the SDQ subscales. CONCLUSIONS: Differences in rates of mental health problems experienced by young children of different weight status appear relatively small. Higher rates of mental health problems experienced by more obese boys may reflect differences in their sociodemographic characteristics rather than their weight status per se. Policies that reduce the number of young children living in poverty or experiencing other adverse social circumstances have the potential to reduce rates of mental health problems experienced by older children with overweight/obesity.  相似文献   
182.
Conditioned stimuli are important for nicotine dependence and may trigger craving and relapse after prolonged nicotine abstinence. However, little is known about the pharmacology of this process. Among the systems that have been shown to play a role in drug-seeking behavior is the endocannabinoid transmission. Therefore, the present study examined the resistance to extinction of drug-seeking behavior elicited by nicotine-associated environmental stimuli and the effects of the selective CB1 cannabinoid antagonist rimonabant (SR141716) on the reinforcing effects of nicotine-related stimuli. Rats were trained to self-administer nicotine (0.03 mg/kg/injection, i.v.) under conditions in which responding was reinforced jointly by response-contingent nicotine injections and stimuli (light and tone). After self-administration acquisition, nicotine was withdrawn and lever pressing was only reinforced by contingent presentation of the audiovisual stimuli. Under such a condition, responding persisted for 3 months, following which nonpresentation of the cues produced a progressive extinction of responding. As expected, rats trained to lever-press for saline injections paired with the audiovisual stimuli did not acquire the self-administration. These findings indicate that the cues required learned association with nicotine to acquire reinforcing properties and to function as conditioned reinforcers. When administered 1 month following nicotine withdrawal, rimonabant (1 mg/kg, i.p.) decreased conditioned behavior. These results showing the persistence of a nicotine-conditioned behavior are congruent with the role of nicotine-related environmental stimuli in nicotine craving in abstinent smokers. Rimonabant, which has been shown previously to reduce nicotine self-administration, may be effective not only as an aid for smoking cessation but also in the maintenance of abstinence.  相似文献   
183.
Purpose: To determine the feasibility of using radiofrequency hyperthermia (RFH) and to enhance the therapeutic effect of herpes simplex virus-thymidine kinase/ganciclovir (HSV-TK/GCV) for the treatment of hepatocellular carcinoma (HCC).

Materials and methods: Human HCC cells (HepG2) were first transfected with lentivirus/luciferase. For both in vitro confirmation and in vivo validation, luciferase-labeled HCC cells and HCC tumour xenografts on mice received different treatments: (i) combination therapy of intratumoral HSV-TK/GCV-mediated gene therapy plus magnetic resonance imaging heating guidewire (MRIHG)-mediated RFH; (ii) gene therapy only; (iii) RFH only; and (iv) phosphate-buffered saline (PBS) as control. Cell proliferation was quantified. Tumour changes were monitored by ultrasound imaging and bioluminescence optical imaging before and at days 7 and 14 after treatments, which were correlated with subsequent histology.

Results: In vitro, the lowest cell proliferation was seen in the combination therapy group compared with control groups (29?±?6% vs. 56?±?9%, 93?±?4%, and 100?±?5%, p?p?p?Conclusion: RFH can enhance HSV-TK/GCV-mediated gene therapy of HepG2 cell line and mice human HCC xenografts, which may open new avenues for effective management of HCC using MR/RFH integrated interventional gene therapy.  相似文献   
184.
185.
Background and purposeTumour hypoxia is associated with a poor prognosis in head and neck squamous cell carcinoma (HNSCC), however there is no accepted method for assessing hypoxia clinically. We aimed to conduct a technical validation of a hypoxia gene expression signature using the TaqMan Low Density Array (TLDA) platform to investigate if this approach reliably identified hypoxic tumours.Materials and methodsTumour samples (n = 201) from 80 HNSCC patients were collected prospectively from two centres. Fifty-three patients received pimonidazole prior to surgery. TaqMan Low Density Array-Hypoxia Scores (TLDA-HS) were obtained by quantitative real-time PCR (qPCR) using a 25-gene signature and customised TLDA cards. Assay performance was assessed as coefficient of variation (CoV).ResultsThe assay was sensitive with linear reaction efficiencies across a 4log10 range of inputted cDNA (0.001–10 ng/μl). Intra- (CoV = 6.9%) and inter- (CoV = 2.0%) assay reproducibility were excellent. Intra-tumour heterogeneity was lower for TLDA-HS (23.2%) than for pimonidazole (67.2%) or single gene measurements of CA9 (62.2%), VEGFA (45.0%) or HIG2 (39.4%). TLDA-HS in HNSCC cell lines increased with decreasing pO2. TLDA-HS correlated with Affymetrix U133 Plus 2.0 microarray HS (p < 0.01) and positive pimonidazole scores (p = 0.005).ConclusionsGene expression measurements of hypoxia using a 25-gene signature and TLDA cards are sensitive, reproducible and associated with lower intra-tumour heterogeneity than assaying individual genes or pimonidazole binding. The approach is suitable for further assessment of prognostic and predictive capability in clinical trial material.  相似文献   
186.
187.
Financial health incentives, such as paying people to lose weight, are being widely implemented by Western nations and large corporations. A growing number of studies have tested the impact of incentives on health behaviors, though few have evaluated the approach on a population-scale. In this issue of the Journal of Medical Internet Research, Liu et al add to the evidence-base by examining whether a single incentive can motivate enrollment and engagement in a preventive eHealth program in a sample of 142,726 Canadian adults. While the incentives increased enrollment significantly (by a factor of about 28), a very high level of program attrition was noted (90%). The “foot in the door” incentive technique employed was insufficient; enrollees received incentives for signing-up for, but not for engaging with, the eHealth program. To supplement this technique and drive sustained behavior change, several theoretically- and empirically-based strategies are proposed. Specifically, incentives indexed to behavioral achievements over time are highlighted as one approach to boost engagement in this population in the future.  相似文献   
188.
External ventricular drains (EVD) are essential in the early management of hydrocephalus and elevated intracranial pressure after subarachnoid hemorrhage (SAH). Once in place, management of the EVD is thought to influence long-term patient outcomes, rates of ventriculitis, incidence of delayed cerebral ischemia, need for a ventriculoperitoneal shunt, and intensive care unit (ICU) and hospital length of stay. The available evidence supports adopting early clamp trials and intermittent cerebrospinal fluid (CSF) drainage. However, a recent survey demonstrated that most neurological ICUs employ the opposite approach of continuously open EVDs and gradual weaning. In this article, we review the literature and arguments for and against the different EVD approaches. We conclude that an early clamp trial and intermittent CSF drainage can be safe and result in fewer EVD complications and shorter length of stay. Given the discrepancy between the available evidence and current practice, more studies on the optimal management of EVDs are warranted with the greatest need for multicenter prospective studies.  相似文献   
189.
Background Candida auris is an emerging multidrug-resistant fungal pathogen associated with bloodstream, wound and other infections, especially in critically ill patients. C. auris carriage is persistent and is difficult to eradicate from the hospital environment.AimWe aimed to pilot admission screening for C. auris in intensive care units (ICUs) in England to estimate prevalence in the ICU population and to inform public health guidance.MethodsBetween May 2017 and April 2018, we screened admissions to eight adult ICUs in hospitals with no previous cases of C. auris, in three major cities. Swabs were taken from the nose, throat, axilla, groin, perineum, rectum and catheter urine, then cultured and identified using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS). Patient records were linked to routine ICU data to describe and compare the demographic and health indicators of the screened cohort with a national cohort of ICU patients admitted between 2016 and 2017.ResultsAll C. auris screens for 921 adults from 998 admissions were negative. The upper confidence limit of the pooled prevalence across all sites was 0.4%. Comparison of the screened cohort with the national cohort showed it was broadly similar to the national cohort with respect to demographics and co-morbidities.ConclusionThese findings imply that C. auris colonisation among patients admitted to ICUs in England is currently rare. We would not currently recommend widespread screening for C. auris in ICUs in England. Hospitals should continue to screen high-risk individuals based on local risk assessment.  相似文献   
190.
Abstract

Impending surgery provides a natural stress paradigm within which the effect of stress on cognitive functioning can be assessed. Cardiac patients scheduled for open-heart surgery were tested for cognitive and emotional status on the day before (N = 130) and 7 days after surgery (N = 109). We correlated the self-reported anxiety and depression scores with the performance on 11 neuropsychological tests on both pre-and postoperative examinations. The results indicate that the significantly elevated emotional arousal in these patients has no relevant effect on their cognitive performance. This finding underlines the validity of neuropsychological testing in more acute clinical settings.  相似文献   
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