Collagen-Based Scaffolds for Cell Therapies in the Injured Brain

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Carriers in Cell-Based Therapies for Neurological Disorders

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Regulatory Compliance when the Rule of Law Is Weak: Evidence from China’s Environmental Reform

What drives regulatees’ behaviors when the institution of law is weak? This study seeks to answer the question by examining environmental regulation enforcement in China. Based on survey and interview data on Hong Kong-owned manufacturing enterprises in the Pearl River Delta Region, Guangdong Province, we found that their decisions to adopt basic and proactive environmental management practices were less driven by concerns for legality than by their perceptions of the regulators’ actions and gestures. Enterprises adopted basic environmental practices to avoid potential punishment and more proactive practices to avoid potentially arbitrary impositions from regulatory officials. Regulated enterprises were more likely to adopt both basic and proactive environmental practices if they had less difficulties in understanding the enforced regulations. These findings suggest important ways in which regulatory compliance behaviors in a developmental context may differ from those in Western countries.postprin

Overestimation of peer smoking prevalence predicts smoking initiation among primary school students in Hong Kong

Purpose: To investigate the relationship between perceived prevalence of smoking and smoking initiation among Hong Kong primary second- to fourth-grade-students. Methods: A cohort of 2,171 students was surveyed in 2006 and again in 2008. Students who perceived ever-smoking prevalence in peers as "none" or "some" were considered as correct (reference group), whereas those who perceived it as "half" (overestimation) or "most/all" (gross overestimation) were considered as incorrect. Results: At baseline, overestimation was found to be cross-sectionally associated with ever-smoking (p < .01). At follow-up, 7.2% of never-smoking students with incorrect estimation at baseline had started smoking, which was 79% (95% confidence interval: 3%-213%), greater than that of 3.7% for those with correct estimation. Among the never-smoking students with incorrect estimation, subsequent correct estimation was associated with 70% (95% confidence interval: 47%-83%) lower risk of smoking initiation compared with persistent incorrect estimation. Conclusion: Overestimation of the prevalence of peer smoking predicted smoking initiation among children. Interventions should be carried out to evaluate whether correcting children's overestimation of peer smoking could reduce smoking initiation. © 2011 Society for Adolescent Health and Medicine.postprin

Lutein enhances survival and reduces neuronal damage in cerebral and retinal ischemia/reperfusion injury

Poster session 3: NeuroprotectionConference theme: Translational Neuroscience: From Molecules To ManPurpose Stroke is one of the leading causes of death worldwide. Protective agents that could diminish the injuries induced by cerebral ischemia/reperfusion (I/R) are crucial to alleviate the detrimental outcome of stroke. Retinal I/R also occurs in many ocular diseases and leads to neuronal death and therefore blindness. Lutein, a safe and potent antioxidant, is known to protect the retina in age-related macular degeneration. The aim of this study is to investigate the protective roles of lutein in cerebral and retinal I/R injury. Methods Two-hour cerebral ischemia was induced by unilateral middle cerebral artery occlusion (MCAo) in mice. Either lutein (0.2mg/kg) or vehicle was given to mice intraperitoneally 1hr after MCAo and 1hr after reperfusion. Neurological deficits were evaluated at 22hr after reperfusion while survival rate was assessed daily until 7 days after reperfusion. Flash electroretinogram (flash ERG) was taken to assess retinal function. After sacrifice, mouse brains were cut into 2mm-thick coronal slices and stained with 2% 2,3,5-triphenyltetrazolium chloride to determine the infarct size after MCAo. Eyes were also enucleated. Paraffin-embedded brain and retinal sections were prepared for TUNEL assay and immunohistochemistry. Protein lysate was collected for Western blotting experiments. Lutein's effect on Müller cells was further evaluated using a model of cobalt chloride-induced hypoxia in immortalized rat Müller cells (rMC-1). Results Higher survival rate, better neurological scores, smaller infarct area and smaller infarct volume were noted in the lutein-treated group. Immunohistochemistry data showed a decrease of immunoreactivity of nitrotyrosine, poly(ADP-ribose) and NFkB in the lutein-treated brains. Western blotting data showed decreased levels of Cox-2, pERK, and pIkB, but increased levels of Bcl-2, heat shock protein 70 and pAkt in the lutein-treated brains. In the retina, severe cell loss in retinal ganglion cell (RGC) layer was noted after I/R injury. Increased oxidative stress was observed in the injured retina. Lutein treatment protected RGC as well as decreased oxidative stress in I/R retina. Lutein treatment also minimized the deterioration of b-wave/a-wave ratio and oscillatory potentials in flash ERG as well as inhibited the up-regulation of GFAP in retinal I/R injury. In the cultured Müller cells, lutein treatment reduced level of nuclear NF-kB together with decreased levels of IL-1b and Cox- 2. Conclusions Post-treatment of lutein protected both the brain and retina from I/R injury. The neuroprotective effect of lutein was associated with reduced oxidative stress. Less production of pro-inflammatory factors from Müller cells suggested an anti-inflammatory role of lutein in retinal ischemic/hypoxic injury. Our results suggest that lutein could diminish the deleterious outcomes of cerebral and retinal I/R probably by its antiapoptotic, anti-oxidative and anti-inflammatory properties. Lutein may have a therapeutic role in protecting the brain in stroke and inner retina in eye diseases with acute ischemia.published_or_final_versio

Sustained Delivery of Bioactive GDNF from Collagen and Alginate-Based Cell-Encapsulating Gel Promoted Photoreceptor Survival in an Inherited Retinal Degeneration Model

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Secondhand Smoke Exposure and Health Services Use among Adolescent Current Smokers

Background:To investigate the associations of secondhand smoke (SHS) exposure with medical consultation and hospitalisation among adolescents in Hong Kong.Methods:A total of 35827 secondary 1 (US grade 7) to secondary 5 students from 85 randomly selected schools completed an anonymous questionnaire on smoking, SHS at home, SHS outside home, medical consultation in the past 14 days, hospitalisation in the past 12 months, and socio-demographic characteristics. Current smoking was defined as any smoking in the past 30 days. SHS exposure was classified as none (reference), 1-4 and 5-7 days/week. Logistic regression yielded adjusted odds ratios (AORs) for medical consultation and hospitalisation in relation to SHS exposure at home and outside home in current smokers. Analyses were also done among never-smokers for comparison.Results:Among all students, 15.9% had medical consultation and 5.2% had been hospitalised. Any SHS exposure at home was associated with AORs (95% CI) for medical consultation and hospitalisation of 1.69 (1.14-2.51) and 2.85 (1.47-5.52) in current smokers, and 1.03 (0.91-1.15) and 1.25 (1.02-1.54) in never-smokers, respectively, (P<0.01 for interaction between smoking status and SHS exposure at home). SHS exposure outside home was generally not associated with medical consultation and hospitalisation in smokers and never-smokers.Conclusions:SHS exposure at home was associated with health services use among adolescent current smokers. Adolescent smokers should be aware of the harm of SHS in addition to that from their own smoking. The evidence helps health care professionals to advise adolescent smokers to avoid SHS exposure and stop smoking. © 2013 Wang et al.published_or_final_versio

Whole-body MRI for preventive health screening:A systematic review of the literature

Background The yield of whole-body MRI for preventive health screening is currently not completely clear. Purpose To systematically review the prevalence of whole-body MRI findings in asymptomatic subjects. Study Type Systematic review and meta-analysis. Subjects MEDLINE and Embase were searched for original studies reporting whole-body MRI findings in asymptomatic adults without known disease, syndrome, or genetic mutation. Twelve studies, comprising 5373 asymptomatic subjects, were included. Field Strength/Sequence 1.5T or 3.0T, whole-body MRI. Assessment The whole-body MRI literature findings were extracted and reviewed by two radiologists in consensus for designation as either critical or indeterminate incidental finding. Statistical Tests Data were pooled using a random effects model on the assumption that most subjects had 5-year) verification of negative findings. Only one study reported false-negative findings, with a proportion of 2.0%. Data Conclusion Prevalence of critical and indeterminate incidental whole-body MRI findings in asymptomatic subjects is overall substantial and with variability dependent to some degree on the protocol. Verification data are lacking. The proportion of false-positive findings appears to be substantial. Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;50:1489-1503

Exercise-Induced Changes in Exhaled NO Differentiates Asthma With or Without Fixed Airway Obstruction From COPD With Dynamic Hyperinflation.

Asthmatic patients with fixed airway obstruction (FAO) and patients with chronic obstructive pulmonary disease (COPD) share similarities in terms of irreversible pulmonary function impairment. Exhaled nitric oxide (eNO) has been documented as a marker of airway inflammation in asthma, but not in COPD. To examine whether the basal eNO level and the change after exercise may differentiate asthmatics with FAO from COPD, 27 normal subjects, 60 stable asthmatics, and 62 stable COPD patients were studied. Asthmatics with FAO (n = 29) were defined as showing a postbronchodilator FEV(1)/forced vital capacity (FVC) ≤70% and FEV(1) less than 80% predicted after inhaled salbutamol (400 μg). COPD with dynamic hyperinflation (n = 31) was defined as a decrease in inspiratory capacity (ΔIC%) after a 6 minute walk test (6MWT). Basal levels of eNO were significantly higher in asthmatics and COPD patients compared to normal subjects. The changes in eNO after 6MWT were negatively correlated with the percent change in IC (r = −0.380, n = 29, P = 0.042) in asthmatics with FAO. Their levels of basal eNO correlated with the maximum mid-expiratory flow (MMEF % predicted) before and after 6MWT. In COPD patients with air-trapping, the percent change of eNO was positively correlated to ΔIC% (rs = 0.404, n = 31, P = 0.024). We conclude that asthma with FAO may represent residual inflammation in the airways, while dynamic hyperinflation in COPD may retain NO in the distal airspace. eNO changes after 6MWT may differentiate the subgroups of asthma or COPD patients and will help toward delivery of individualized therapy for airflow obstruction

Cross-sectional difference in BMI between senior and junior students predicts prospective change in BMI at the school level

Poster Presentation: abstract no. 1196The Conference abstracts's website is located at http://www2.kenes.com/apccn/scientific/Pages/ListofAbstracts.aspxOBJECTIVES: To examine whether cross-sectional BMI difference between senior and junior secondary school students was correlated with prospective changes in BMI at the school level. BACKGROUND: Schools are known to exert prospective influences on adolescent BMI. The school effects may also be reflected in cross-sectional BMI differences between senior and junior students in each school. Schools could quickly be identified for weight-control interventions if such cross-sectional differences could predict prospective changes in BMI. METHODS: In the Hong Kong Student …postprin