Graphene oxide integrated silicon photonics for detection of vapour phase volatile organic compounds.

The optical response of a graphene oxide integrated silicon micro-ring resonator (GOMRR) to a range of vapour phase Volatile Organic Compounds (VOCs) is reported. The response of the GOMRR to all but one (hexane) of the VOCs tested is significantly higher than that of the uncoated (control) silicon MRR, for the same vapour flow rate. An iterative Finite Difference Eigenmode (FDE) simulation reveals that the sensitivity of the GO integrated device (in terms of RIU/nm) is enhanced by a factor of ~2, which is coupled with a lower limit of detection. Critically, the simulations reveal that the strength of the optical response is determined by molecular specific changes in the local refractive index probed by the evanescent field of the guided optical mode in the device. Analytical modelling of the experimental data, based on Hill-Langmuir adsorption characteristics, suggests that these changes in the local refractive index are determined by the degree of molecular cooperativity, which is enhanced for molecules with a polarity that is high, relative to their kinetic diameter. We believe this reflects a molecular dependent capillary condensation within the graphene oxide interlayers, which, when combined with highly sensitive optical detection, provides a potential route for discriminating between different vapour phase VOCs.

Effects of Senior Simulation Suit Programme on nursing students' attitudes towards older adults: A randomized controlled trial.

BACKGROUND: As populations age worldwide, nursing educational institutions need to train nurses not only to provide health care services specific to the elderly, but also to have a positive attitude as they work. The present study aimed to investigate the efficacy of a Senior Simulation Suit Programme (SSSP). The SSSP, which focused on mimicking the physiological experiences of an 80 year-old person, was hypothesized to increase the wearer's positive attitude towards older adult care. METHODS: A single-blinded, randomized controlled trial was used to evaluate the efficacies of SSSP. One hundred and thirty-nine (139) nursing students were randomly assigned to either SSSP group (n = 69) or to a control group (n = 70) with "placebo clothing", i.e. clothing that mimicked old age but did not actually impair faculties. Two instruments-Kogan Attitudes Towards Old People Scale (KAOP) and a 1-item scale on Willingness To Care for Older People Scale (WCOP)-were used for data collection at baseline and at completion of SSSP. A Chinese version of Palmore's Facts Aging Quiz (C-FAQ) was used to assess nursing students' knowledge about adult care, and a questionnaire was developed to collect demographic information at baseline. RESULTS: No significant difference between the two groups was found. A significant increase of positive attitudes and of willingness to serve older adults was found in both the control group and the group wearing SSSP. CONCLUSION: Both the SSSP and control intervention could improve the attitudes of nursing students towards older adult care. This study suggests that wearing whatever the nursing students associate with being old, will improve their attitude towards older adult care.

2-Chloroacetamidine, a novel immunomodulator, suppresses antigen-induced mouse airway inflammation.

BACKGROUND: Citrullination is a presently under-recognized posttranslational protein modification catalyzed by PAD enzymes. Immune responses to citrullinated neo-epitopes are identified in a growing number of inflammatory and autoimmune diseases. However, the involvement of hypercitrullination in the pathogenesis of bronchial asthma is still unknown. METHODS: As main experimental tool, we examined the effect of 2-chloroacetamidine (2CA), a PAD enzyme inhibitor, on OVA-immunized and airway-challenged BALB/c mice; a commonly used model of allergic airway inflammation. We also measured the effect of 2CA on ex vivo lymphocytes and cell lines. RESULTS: In vivo, 2CA dramatically suppressed lung tissue hypercitrullination, inflammatory cell recruitment, and airway-Th2 cytokine secretion. 2CA also suppressed systemic OVA-specific and total IgE production dramatically, effectively preventing de novo and diminishing established disease without measurably impacting general immunocompetence. In vitro, 2CA markedly inhibited the proliferation of mouse and human T cells with cell cycle block and apoptosis during a limited, postactivation phase. CONCLUSIONS: 2CA acts as narrow-spectrum immunosuppressant that selectively targets lymphocyte populations involved in active inflammatory tissue lesions. If hypercitrullination is generated in patients with asthma, 2CA may represent a novel disease modulator for human asthmatics/allergic diseases.

Condoms used but sex not well protected.

Condom use is often equated to safer sex. The prevalence of condom use during sex work among female sex workers (FSW) in China is high. Condom use, however, co-exists with condom failure and improper use and hence risk of HIV transmission. In a cross-sectional study, we interviewed 195 FSW in Shenzhen, China. The prevalence of condom use in the last episode of sex work was 97.4 %, However, respectively 53.8 and 86.2 % had experienced at least one condition of condom failure that may lead to genital contact (wearing condoms after penetration, condom breakage/slippage, condoms removed by clients) and at least one condition of improper condom use (not removing air from the tip of the condom, not pulling it down to the root of penis and not choosing good quality condoms). Factors of individual level (e.g. never choosing high quality condoms for sex work), inter-personal level (e.g. agreement to have unprotected sex if fond of clients or paid more) and environmental/structural level (e.g. non-availability of condoms) were associated with various types of condom failure and improper use. Although HIV prevention interventions have increased prevalence of condom use among FSW, the risk of HIV transmission may still be high as "unsafe" sex due to condom failure and improper use is prevalent. Interventions promoting safer sex need to address such issues and take socio-ecological factors into account. Condom use during sex work is not equivalent to well protected sex as the protective effects could be compromised by frequent condom failure and improper use.

Referral strategy for early recognition of axial spondyloarthritis: consensus recommendations from the Hong Kong Society of Rheumatology.

Low back pain is one of commonest problems prompting a visit to the family physician. Up to 5% of patients with chronic low back pain in the primary care setting are diagnosed as having spondyloarthritis, which includes the prototype disease ankylosing spondylitis. Making a diagnosis of ankylosing spondylitis is often delayed for years, leading to significant pain, impairment of quality of life, disability and productivity loss. A recent breakthrough in the treatment of spondyloarthritis is the anti-tumor necrosis factor-alpha biologics, which lead to rapid relief of pain and inflammation, and improvement in all clinical parameters of the disease. Patients with early spondyloarthritis often respond better than those with late established disease. With proper recognition of inflammatory back pain, and the use of magnetic resonance imaging, spondyloarthritis can now be diagnosed much earlier before features are evident on plain radiographs. Referral to the rheumatologist based on onset of back pain (> 3 months) before the age of 45 years, and an inflammatory nature of the pain, or the presence of human leukocyte antigen-B27, or sacroiliitis by imaging, have been confirmed in multi-center international studies to be a pragmatic approach to enable early diagnosis of spondyloarthritis. This referral strategy has recently been adopted by the Hong Kong Society of Rheumatology for primary care physicians and non-rheumatology specialists.

Prevalence of seasonal influenza vaccination and associated factors in people with chronic diseases in Hong Kong.

Chronic disease patients are at high risk of developing serious influenza-related complications. This study investigated the prevalence of seasonal influenza vaccination (IV) and associated factors in such patients. A random sample of 704 Chinese adults with chronic disease was anonymously interviewed by telephone; 35·8% of them had ever taken up IV and 22·7% did so during the last flu season. The most frequently mentioned facilitator was recommendation made by a healthcare worker (HCW). Knowledge that IV is required annually, perceived severe health impacts of influenza, and recommendation made by a HCW were positively associated with previous IV and intention to take up IV in the next year, while perceived side-effects was inversely associated with previous IV and intention to take up IV. The coverage of IV in this study population was low. HCWs should clarify IV-related health beliefs in chronic disease patients and actively advise them to take up IV.

Prevalence and determinants of influenza vaccination in the Hong Kong Chinese adult population.

BACKGROUND: The study examined the prevalence and associated factors of influenza vaccination (IV) among the general adult population in Hong Kong. METHODS: A population-based, random telephone survey interviewed 1,102 Hong Kong Chinese adults aged 18-64 years old in 2006. RESULTS: Of all study participants, 95.5% had heard of IV, and only 28.1% had ever received IV. Associated factors included knowledge that IV is required annually, variables related to the Health Belief Model (HBM) (eg, perceived adverse effects, perceived efficacy), and advices given by health care professionals. CONCLUSIONS: The prevalence of IV was moderately low and factors related to the HBM were found predictive of IV.

Psychological factors in association with uptake of voluntary counselling and testing for HIV among men who have sex with men in Hong Kong.

OBJECTIVES: To investigate the prevalence and factors associated with uptake of voluntary counselling and testing (VCT) for human immunodeficiency virus (HIV) among men who have sex with men (MSM) in Hong Kong. STUDY DESIGN: Cross-sectional study. METHODS: A total of 389 MSM were recruited from gay venues. An additional 188 MSM were recruited through the Internet. Data were collected via face-to-face interviews using a self-administered anonymous questionnaire or via an electronic questionnaire accessible via local gay-friendly websites. The associations between independent and dependent variables (VCT uptake in lifetime and in last 12 months) were examined by logistic regression models. RESULTS: The prevalence rates for lifetime and 12-month uptake of VCT were 56.5% and 39.4%, respectively. Adjusting for significant background variables, all cognitive variables (attitudes, subjective norms, perceived control and behavioural intention) that were derived from the Theory of Planned Behaviours (TPB) were significantly associated with both lifetime and 12-month uptake of VCT [adjusted odds ratio (AOR) 0.56-4.71, P < 0.05]. Perceived fear of contracting HIV and perceived discrimination towards local MSM were associated with a lower likelihood of 12-month uptake of VCT (AOR 0.63, P < 0.05) and lifetime uptake (AOR 0.65, P < 0.05). In the summary models, variables derived from the TPB (subjective norms, perceived control and behavioural intention) were independently associated with lifetime and 12-month uptake of VCT (OR 0.64-2.78, P < 0.05; OR 2.39-3.21, P < 0.05, respectively). Fear of contracting HIV was associated with VCT uptake in the last 12 months (OR 0.55, P < 0.05). CONCLUSIONS: Psychological factors are associated with VCT uptake. The TPB and other health behavioural theories should be taken into account when designing VCT promotion campaigns.

Monitoring of perceptions, anticipated behavioral, and psychological responses related to H5N1 influenza.

BACKGROUND: The aim of this study was to monitor changes in behavioral and emotional responses to human H5N1 in the community over a 28-month period (from November 2005 to February 2008). METHODS: A total of 3,527 Hong Kong Chinese adults were interviewed by telephone within the framework of six identical cross-sectional surveys carried out during the 28-month study period. Given a hypothetical scenario that two to three new human-to-human H5N1 cases had been reported in Hong Kong, the trends of the respondents in various H5N1-related risk perceptions, anticipated personal psychological responses, and anticipated personal preventive behaviors were investigated. RESULTS: Over time, a decreased proportion of the respondents (1) felt susceptible to contracting H5N1, (2) expected a large outbreak would eventually occur, (3) believed that the impacts of H5N1 were worse than those of severe acute respiratory syndrome (SARS), and (4) anticipated adopting more types of preventive measures and experiencing mental distress in the case of a small-scale outbreak in Hong Kong (AOR from 0.27 to 0.43, p < 0.001), but the public remained vigilant on public health behaviors, such as hand-washing. The prevalence of misconceptions on the mode of transmission declined, but remained high; perceptions on the fatality of H5N1 remained largely underestimated. The SARS experience and unconfirmed beliefs about the transmission modes were associated with variables on anticipated preventive behaviors and emotional distress. CONCLUSION: Starting in 2005 through to 2008, respondents perceived a decreasing level of susceptibility, severity, and anticipated stress towards a hypothetical human-to-human H5N1 outbreak, possibly due to the low efficiency of transmission. The public's general preparedness was still relatively good and rational, even though individual preventive behaviors were less common. However, misconceptions were prevalent among the respondents. Based on these results, public education is warranted to rectify these misconceptions.

Factors in association with acceptability of A/H1N1 vaccination during the influenza A/H1N1 pandemic phase in the Hong Kong general population.

A random population-based telephone survey (n=301) was conducted among the Hong Kong general population in July 2009. Past history of seasonal influenza vaccination (OR=2.59-3.13) was associated with intention to take up A/H1N1 vaccination under three hypothetical scenarios (provided at HK$200). Adjusting background variables, other significant factors were identified by stepwise models: perceived side effects (OR=0.33), family members' recommendations and friends' acceptability toward the vaccine (OR=2.80-4.74). In contrast to other studies on seasonal influenza and A/H1N1 vaccination, perceived susceptibility and perceived severity related to influenza A/H1N1 were non-significant. Cultural differences may therefore exist.

Prevalence of psychological problems and relationships with condom use and HIV prevention behaviors among Chinese female sex workers in Hong Kong.

The present study investigated the prevalence of psychological problems and their relationships with relevant HIV prevention behaviors among female sex workers (FSWs). An anonymous cross-sectional survey was conducted. With a mapping exercise, 293 Chinese FSWs were recruited from a red-light district in Hong Kong. Results showed high prevalence of psychological problems among FSWs: substance use (40.4%), probable depression (53.9%), self-harm tendencies (34-38%), poor self-esteem (48-52%), and pessimistic future outlook (46-47%). Inconsistent condom use was common (51% with clients, 23% with one-night-stand sex partner, and 73% with boyfriends). Over 70% had not used HIV-related prevention services in the last 6 months. Multivariate analyses indicated that psychological problems were significantly associated with inconsistent condom use and non-use of prevention services. The poor psychological well-beings of FSWs have important public health implications. Relevant professional services should be provided and integrated with HIV prevention efforts.

Marchiafava-Bignami disease with widespread lesions and complete recovery.

MBD is a rare disorder strongly associated with alcoholism. It is characterized pathologically by demyelination and necrosis of the corpus callosum. MBD presents with severe neurologic deficits and significant sequelae developing in most survivors. We report a patient with total clinical recovery. Serial MR imaging demonstrated typical lesions with restricted diffusion in the acute stage and total resolution without atrophy or cystic change.

From gene expression to serum proteins: biomarker discovery in ankylosing spondylitis.

OBJECTIVES: Studying post-infliximab gene expression changes could provide insights into the pathogenesis of ankylosing spondylitis (AS). METHODS: Gene expression changes were screened by microarray on peripheral blood RNA of 16 AS patients at baseline and 2 weeks post-infliximab, and selected results were confirmed by quantitative real-time (qRT)-PCR. Corresponding serum-soluble LIGHT (sLIGHT) was estimated by ELISA and the fold change in sLIGHT was correlated to the fold change in erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and the Bath AS disease activity index. RESULTS: Post-infliximab, 69% of the patients (11/16) achieved an ASAS20 response. Six candidate genes were differentially expressed by microarray; four of which were validated by qRT-PCR. sLIGHT showed the most significant difference. There was good correlation of baseline sLIGHT with CRP (R = 0.60; p = 0.01) and ESR (R = 0.51; p = 0.04). The fold change in sLIGHT correlated with change in both CRP (R = 0.71, p = 0.002) and ESR (R = 0.77, p<0.001). CONCLUSION: LIGHT is significantly downregulated by infliximab. sLIGHT correlated well with changes in inflammatory markers.

Successful treatment of leflunomide-induced acute pneumonitis with cholestyramine wash-out therapy.

Drug-induced acute pneumonitis is a rare but potentially fatal adverse drug reaction. A high index of suspicion is needed for early diagnosis as it mimics community acquired pneumonia and interstitial lung disease that can occur in rheumatoid arthritis. We report a 32-year-old Chinese lady who suffered from leflunomide-induced pneumonitis and improved dramatically after receiving cholestyramine wash-out therapy. This case illustrates the need for clinical alertness to this potentially fatal complication. When in doubt, discontinuation of leflunomide and empirical wash-out therapy should be administered without delay.

Acceptability of A/H1N1 vaccination during pandemic phase of influenza A/H1N1 in Hong Kong: population based cross sectional survey.

OBJECTIVE: To investigate the intention of the Hong Kong general population to take up vaccination against influenza A/H1N1. Setting Cross sectional population based anonymous survey. Participants Random sample of 301 adults interviewed by telephone (response rate 80%). MAIN OUTCOME MEASURE: Intention to take up vaccination against influenza A/H1N1 under five hypothetical scenarios: vaccination is free; vaccination per dosage costs less than $HK100 ( pound8; euro9; $13), $HK101-200, or more than $HK200; and no data are available on the efficacy and safety of the vaccine. Results 45% (n=135) of the participants reported that they would be highly likely take up vaccination if it was free. When vaccination incurred a cost, however, the prevalence of uptake decreased: 36% (n=108) would take up vaccination if it cost less than $HK100, 24% (n=72) if it cost $HK101-200, and 15% (n=45) if it cost more than $HK200; and in absence of proved efficacy and safety decreased to 5% (n=14). Moreover, 32% (n=95) considered universal A/H1N1 vaccination unnecessary. Overall, 39% (n=117) of participants believed that A/H1N1 vaccination would prevent the virus being contracted; 63% (n=189) erroneously believed that efficacy of the vaccine had been confirmed by clinical trials, and 16% (n=49) believed that it is necessary for everyone in Hong Kong to take up vaccination against influenza A/H1N1. Conclusions The uptake of vaccination against influenza A/H1N1 by the general population of Hong Kong is unlikely to be high and would be sensitive to personal cost. Evidence about safety and efficacy is critical in determining the prevalence of uptake of vaccination.