Creating allies: qualitative exploration of young women's preferences for PrEP methods and parents' role in PrEP uptake and user support in urban and rural Zambia

BACKGROUND

Zambian adolescent girls and young women (AGYW) have high HIV incidence and face barriers to the use of pre-exposure prophylaxis (PrEP). Parental support improves PrEP use and adherence in some settings, but negative parental attitudes toward HIV prevention may inhibit engagement with AGYW. We explored perceptions of future PrEP methods among AGYW and parents and parent-youth engagement on HIV prevention and PrEP use.

METHODS

We conducted a qualitative descriptive study among AGYW and parents of AGYW in five provinces in Zambia in September-October 2021. We conducted 10 focus group discussions (FGDs) and four in-depth interviews (IDIs) with AGYW participants (n = 87) and seven FGDs and four IDIs among parents of AGYW (n = 62). All FGDs and IDIs were audio-recorded, transcribed verbatim, and analyzed to identify qualitative themes.

RESULTS

Most AGYW participants preferred the discreet nature and longer duration of injectable PrEP compared to the PrEP ring and oral PrEP. Many AGYWs reported inability to disclose PrEP use to their parents due to lack of parental support based on cultural taboos against premarital sex. Nevertheless, AGYW participants said they would like to talk to their parents about PrEP so their parents could support their use. Many parents also described difficulties discussing PrEP with their daughters because of cultural and religious beliefs about abstinence from sex before marriage. However, parents acknowledged that the threat of HIV is real and said they need PrEP knowledge and guidance on speaking with their children about HIV prevention and PrEP.

CONCLUSIONS

Although many parents are currently not playing a role in daughters' decisions about PrEP use, both parents and AGYW are willing to engage with each other on HIV prevention issues. To foster parent-child engagement, HIV prevention programs should not only provide information about PrEP but also address social norms that impede discussion of HIV prevention and equip both parents and AGYW with skills and support for such conversations. Community sensitization is also needed as new PrEP products are introduced, to create an enabling environment for parent-child engagement by increasing awareness, countering misconceptions, and reducing stigma.

Clinical Outcomes of Conservative Treatment for Low-Risk Ductal Carcinoma in Situ: A Systematic Review and Pooled Analysis

AIMS

The current gold standard of treatment for ductal carcinoma in situ (DCIS) is surgical resection with or without adjuvant radiotherapy. However, the increased detection and radical treatment of DCIS did not result in a declined incidence of invasive breast cancers, leading to the debate if DCIS has been overtreated. While ongoing randomised controlled trials on active surveillance of DCIS are still in progress, this systematic review aims to evaluate the best evidence on conservative treatment for DCIS from the literature.

MATERIALS AND METHODS

This systematic review was conducted in line with the PRISMA statement. We included all relevant studies published up to June 2022 for analysis. The primary outcomes were overall survival and breast cancer-specific survival (BCSS) of conservative treatment for DCIS.

RESULTS

Three studies, with a total of 34 007 women with low-risk DCIS, were included in the analysis. Active and conservative treatments both resulted in excellent 10-year BCSS, with no statistically insignificant difference (98.6% versus 96.0%, 31 478 women). One study comparing 5-year BCSS of active and conservative treatments only in subjects aged over 80 years also reported [AQ1]an insignificant difference (98.2% versus 96.0%, 2529 women). One study measuring 5- and 10-year overall survival between the treatment groups also reported [AQ1]an insignificant difference (5-year: 96.2% versus 92.4%; 10-year: 85.6% versus 86.7%, 31 106 women).

CONCLUSION

BCSS between active and conservative treatment for women with low-risk DCIS is both excellent and comparable, suggesting that conservative treatment is a possible alternative without compromising survival.

A Field Test of the NORMAL Job Aid With Community Health Workers in Kenya to Address Contraceptive-Induced Menstrual Changes

INTRODUCTION

Concerns about contraceptive-induced menstrual changes (CIMCs) contribute to nonuse and discontinuation of family planning (FP). Current counseling materials inadequately address these concerns. After obtaining initial feedback, we field-tested an adapted version of the NORMAL job aid that guides community health workers on how to counsel women about CIMCs. The field test aimed to help understand how the job aid was used, the challenges faced in using it, and recommendations to improve the job aid.

METHODS

Sixteen community health volunteers (CHVs) from 2 subcounties in Kenya were trained on the 2-page job aid and given copies of the job aid to use with clients. Six to 8 weeks after the training, we interviewed the CHVs about their experiences using the job aid. The interviews were audio-recorded, transcribed, and analyzed to identify qualitative themes.

RESULTS

All 16 CHVs reported using the job aid each time they counseled. All liked it and said they used it because it gave them new information and made counseling easier. All reported offering the job aid to most clients and that most clients accepted a copy. CHVs noted clients referred their friends and family to them after counseling using the job aid. CHVs said the job aid reduced clients' and their male partners' concerns about CIMCs and helped clients select or switch FP methods. Most CHVs did not have suggestions for improving the job aid.

CONCLUSION

The job aid was highly acceptable to the CHVs who participated in this small assessment. According to the CHVs, it increased counseling effectiveness and may help increase uptake and continued use of FP methods directly through counseling or indirectly through diffusion in the community. Though further research is needed in other settings and to quantify its impact, we recommend this promising job aid be adapted for wider use.

20-MHz phased array ultrasound transducer for in vivo ultrasound imaging of small animals

In vivo ultrasound imaging with phased array transducers is of great importance for both clinical application and biomedical research. In this work, relaxor ferroelectric PMN-0.28PT single crystal with very high piezoelectric constant d₃₃ ≥ 2000 pC/N and electromechanical coupling coefficient k₃₃ ∼ 0.92 is used to fabricate high-frequency phased array transducers. A 128-element 20-MHz phased array transducer is successfully fabricated, and the optimized performance of -6 dB average bandwidth of ∼ 84 % and insertion loss of -43 dB are achieved. The axial and lateral imaging resolutions of the transducer are determined to be 81 µm and 243 µm, respectively. With Verasonics image platform, in vivo fisheye images are acquired, demonstrating the potential application of our developed high-frequency phased array transducer for biomedical research on small animals.

Effect of a Popular Web Drama Video Series on HIV and Other Sexually Transmitted Infection Testing Among Gay, Bisexual, and Other Men Who Have Sex With Men in Singapore: Community-Based, Pragmatic, Randomized Controlled Trial

Background

Gay, bisexual, and other men who have sex with men (GBMSM) are at disproportionately higher risk of acquiring HIV and other sexually transmitted infections (STI). While HIV/STI testing rates among GBMSM are increasing worldwide, they remain suboptimal in a variety of settings. While many studies have attempted to evaluate the efficacy of a variety of community-based campaigns, including peer and reminder-based interventions on HIV/STI testing, however few have attempted to do so for a web drama series.

Objective

This study evaluates the effectiveness of a popular web drama video series developed by a community-based organization in Singapore for GBMSM on HIV and other STI testing behaviors.

Methods

The study is a pragmatic, randomized controlled trial to evaluate a popular web drama video series developed by a community-based organization in Singapore for GBMSM. A total of 300 HIV-negative, GBMSM men in Singapore aged 18 to 29 years old were recruited and block-randomized into the intervention (n=150) and control arms (n=150). Primary outcomes included changes in self-reported intention to test for, actual testing for, and regularity of testing for HIV, syphilis, chlamydia or gonorrhea, while secondary outcomes include changes in a variety of other knowledge-based and psychosocial measures at the end of the study period.

Results

Overall, 83.3% (125/150) of participants in the intervention arm completed the proof of completion survey, compared to 88.7% (133/150) in the control arm. We found improvements in self-reporting as a regular (at least yearly) tester for HIV (15.9% difference, 95% CI, 3.2% to 28.6%; P=.02), as well as chlamydia or gonorrhea (15.5% difference, 95% CI, 4.2% to 26.9%; P=.009), indicating that the intervention had positively impacted these outcomes compared to the control condition. We also found improvements in participants’ intentions to test for HIV (16.6% difference, 95% CI, 4.3% to 28.9%; P=.009), syphilis (14.8% difference, 95% CI, 3.2% to 26.4%; P=.01), as well as chlamydia or gonorrhea (15.4% difference, 95% CI, 4.2% to 26.6%; P=.008), in the next 3 months, indicating that the intervention was effective in positively impacting intention for HIV and other STI testing among participants.

Conclusions

There are clear benefits for promoting intentions to test regularly and prospectively on a broad scale through this intervention. This intervention also has potential to reach GBMSM who may not have access to conventional HIV and other STI prevention messaging, which have typically been implemented at sex-on-premises venues, bars, clubs, and in sexual health settings frequented by GBMSM. When coupled with community or population-wide structural interventions, the overall impact on testing will likely be significant.

Trial Registration

ClinicalTrials.gov NCT04021953; https://clinicaltrials.gov/ct2/show/NCT04021953

International Registered Report Identifier (IRRID)

RR2-10.1136/bmjopen-2019-033855

Uptake of oral fluid-based HIV self-testing among men who have sex with men and transgender women in Thailand

Background

Suboptimal uptake of HIV testing remains a primary bottleneck to HIV prevention and treatment for men who have sex with men (MSM) and transgender women (TGW) in Thailand. The World Health Organization has recommended HIV self-testing (HIVST) as an additional strategic HIV service. However, HIVST has not been fully endorsed and implemented in many countries in Southeast Asia. The aim of this study was to assess the uptake of oral fluid-based HIVST in MSM and TGW populations in Thailand.

Methods

During 2017 and 2018, we conducted a cross-sectional study using convenience sampling to enroll 2,524 participants from three major urban areas. Participants were recruited during outreach and online activities and were offered unassisted or assisted HIVST, or referral to HIV testing services. A descriptive analysis was performed for summarizing data.

Results

A total of 2,502 participants (1,422 MSM and 1,082 TGW) were included in the analysis with about one-third (36.1%) of them being first-time testers. Among all participants enrolled in the study, a total of 2,486 participants (99.3%) selected HIVST versus referral to HIV testing services. Of those who selected HIVST, 2,095 (84.3%) opted for assisted HIVST while the rest opted for unassisted HIVST: 1,148 of 1,411 MSM (81.4%) and 947 of 1,075 TGW (88.1%) selected assisted HIVST. While no serious adverse events were reported during the study, we found that among 179 participants who needed a confirmatory test and were referred to HIV testing services, 108 (60.3.4%) accessed these later services.

Conclusions

This study demonstrated a high uptake of oral fluid-based HIVST among MSM and TGW populations in Thailand and that HIVST could be scaled up through the national epidemic control program. However, a better understanding of HIV testing-seeking behavior and innovative follow-up solutions are needed to improve and monitor linkages to services for people who undertake HIVST.

Potential interactions between the pathways to diagnosis of HIV and other STIs and HIV self-testing: insights from a qualitative study of gay, bisexual and other men who have sex with men in Singapore

Objectives

This study draws on qualitative insights on the barriers and facilitators to HIV testing, as well as perceptions of HIV self-testing (HIVST), to propose a framework to understand not only the benefits but also potential knock-on implications of introducing HIVST in the context of other STI testing.

Methods

We conducted semistructured, in-depth interviews with 30 gay, bisexual and other men who have sex with men aged 18 and 39 years old in Singapore. Interview topics included barriers and facilitators to HIV and other STI testing, as well as perceptions of HIVST. Interviews were audio-recorded, transcribed, coded and analysed using thematic analysis.

Results

For HIV testing, participants cited the perceived risk of acquiring, susceptibility to and symptoms of HIV as internal motivators, while social influence and accessibility of HIV testing services were external motivators. For STI testing, perceived symptoms and partner notification of STI were reported as internal and external motivators, respectively. Availability of bundle tests, starting a new relationship and instances of mandatory testing motivated both simultaneous HIV and other STI testing. The fear of a positive diagnosis and lack of confidentiality were cited as internal and external barriers to HIV testing, respectively, while low perceived severity of other STI and the cost of STI tests were cited as internal and external barriers to other STI testing, respectively. We identified pathways to HIV and other STI testing and discussed how the introduction of HIVST may reduce opportunities for other STI testing.

Conclusions

The findings of this study suggest that introducing HIVST might weaken linkages to other STI testing if alternative strategies of promoting other STI testing are not simultaneously implemented. We recommend that future interventions address both the risks of HIV and other STI simultaneously, and that structural interventions promoting HIV and other STI preventions be balanced accordingly.

Laparoscopic transgastric resection of gastroduodenal intussusception due to gastric leiomyoma

Gastric leiomyoma of the antrum intussuscepted into first part of the duodenum is a rare complication. We report here an 80-year-old woman who presented at the Sarawak General Hospital, Kuching, Sarawak, Malaysia with early satiety and epigastric fullness for 3 months. She had no prior medical or surgical history other than an uneventful open cholecystectomy. Upper endoscopy showed a large submucosal mass in the first part of duodenum with pyloric converging gastric folds. Computed tomography scan of the abdomen showed a gastroduodenal intussusception with a 4x6cm mass at the junction between the first and second part of duodenum. Laparoscopic transgastric resection was performed. Histopathological examination of the resected specimen confirmed leiomyoma. She remained well at 43 months follow-up.

Chemsex among gay, bisexual, and other men who have sex with men in Singapore and the challenges ahead: A qualitative study

BACKGROUND

Sexualised substance use, or 'chemsex' has been shown to be a major factor driving the syndemic of HIV/AIDS in communities of gay, bisexual, and other men who have sex with men (GBMSM) around the world. However, there is a paucity of research on chemsex among GBMSM in Singapore due to punitive drug laws and the criminalisation of sexual behaviour between men. This qualitative descriptive study is the first to explore perceptions towards, motivators to engaging in, and the barriers to addressing the harms associated with chemsex among GBMSM in Singapore.

METHODS

We conducted 30 semi-structured in-depth interviews with self-identifying GBMSM between the ages of 18-39 in Singapore following a purposive sampling strategy. Interview topics included participants' perceptions of drug use among GBMSM in Singapore, perceptions towards chemsex, reasons for drug use and chemsex, and recommendations to address the harms associated with chemsex in Singapore. Interviews were audio-recorded, transcribed, coded, and analysed using thematic analysis.

RESULTS

Participants reported that it was common to encounter chemsex among GBMSM in Singapore as it could be easily accessed or initiated using social networking phone apps. Enhancement and prolongation of sexual experiences, fear of rejection from sexual partners and peers, and its use as a means of coping with societal rejection were three main reasons cited for engaging in chemsex. The impact of punitive drug laws on disclosure and stigmatisation of GBMSM who use drugs were reported to be key barriers towards addressing chemsex. Participants suggested using gay-specific commercial venues as avenues for awareness and educational campaigns, and social media to reach out to younger GBMSM.

CONCLUSIONS

This study highlights the complexities behind chemsex use among GBMSM in Singapore, and the range of individual to institutional factors to be addressed. We recommend that community-based organisations and policy-makers find ways to destigmatise discussion of chemsex and provide safe spaces to seek help for drug use.

Anodic aluminum oxide-epoxy composite acoustic matching layers for ultrasonic transducer application

The goal of this work is to demonstrate the application of anodic aluminum oxide (AAO) template as matching layer of ultrasonic transducer. Quarter-wavelength acoustic matching layer is known as a vital component in medical ultrasonic transducers to compensate the acoustic impedance mismatch between piezoelectric element and human body. The AAO matching layer is made of anodic aluminum oxide template filled with epoxy resin, i.e. AAO-epoxy 1-3 composite. Using this composite as the first matching layer, a ∼12MHz ultrasonic transducer based on soft lead zirconate titanate piezoelectric ceramic is fabricated, and pulse-echo measurements show that the transducer exhibits very good performance with broad bandwidth of 68% (-6dB) and two-way insertion loss of -22.7dB. Wire phantom ultrasonic image is also used to evaluate the transducer's performance, and the results confirm the process feasibility and merit of AAO-epoxy composite as a new matching material for ultrasonic transducer application. This matching scheme provides a solution to address the problems existing in the conventional 0-3 composite matching layer and suggests another useful application of AAO template.

Low-field Switching Four-state Nonvolatile Memory Based on Multiferroic Tunnel Junctions

Multiferroic tunneling junction based four-state non-volatile memories are very promising for future memory industry since this kind of memories hold the advantages of not only the higher density by scaling down memory cell but also the function of magnetically written and electrically reading. In this work, we demonstrate a success of this four-state memory in a material system of NiFe/BaTiO₃/La_0.7Sr_0.3MnO₃ with improved memory characteristics such as lower switching field and larger tunneling magnetoresistance (TMR). Ferroelectric switching induced resistive change memory with OFF/ON ratio of 16 and 0.3% TMR effect have been achieved in this multiferroic tunneling structure.

An Electronic Nursing Patient Care Plan Helps in Clinical Decision Support

Information technology can help to improve health care delivery. The utilisation of informatics principle enhances the quality of nursing practices through improved communication, documentation and efficiency. The Nursing Profession constitutes 34% of the total workforce in the Hong Kong Hospital Authority (HA) and includes 21,000 nurses in 2012. To enhance the quality of care and patient safety in both hospitals and community care setting, it is essential that an integrated electronic decision support system for nurses is designed to track documentation and support care or service including observations, decisions, actions and outcomes throughout the care process at each point-of-care. The Patient Care Plan project was set up to achieve these objectives. The Project adheres to strict documentation information architecture to ensure data sharing is freely available. Preliminary results showed very promising improvement in clinical care.

Comparative in vitro cytotoxicity study on uncoated magnetic nanoparticles: effects on cell viability, cell morphology, and cellular uptake

Magnetic iron oxide nanoparticles (MIONPs) must be biocompatible, and a thorough knowledge on their potential cytotoxicity is crucial for their biomedical applications. However, the detailed study about the effects of iron oxide nanoparticles on cell viability, cell morphology, and cellular uptake of different mammalian cells is still insufficient. In this paper, comparative cytotoxicity study of uncoated magnetite nanoparticles at different concentrations was performed on human cervical cancer cell line (HeLa) and immortalized normal human retinal pigment epithelial cell line (RPE). The size, structure, and magnetic behavior of the MIONPs were characterized using transmission electron microscopy (TEM), X-ray diffractometry (XRD), and vibrating sample magnetometry (VSM) respectively. After 24-hour incubation with the MIONPs, the cell viability was determined by live/dead assay, the cell morphology at high magnification was observed under scanning electron microscopy (SEM), and the cellular uptake of MIONPs was measured under TEM and verified by energy-dispersive X-ray spectroscopy (EDX) analysis. Our results indicate that the uncoated MIONPs at a high concentration (0.40 mg/ml) were toxic to both HeLa and RPE cells. However, the cytotoxicity of uncoated MIONPs at low concentrations was cell-type specific, and RPE cells were more susceptible to these MIONPs than HeLa cells. The effects of the MIONPs on cell morphology and the nanoparticles uptake also showed different features between these two cell lines. Hence cell type should be taken into consideration in the in vitro cytotoxicity study of uncoated MIONPs. Additionally, it should be noticed that the cell morphological changes and the uptake of nanoparticles can take place even though no toxic effect of these MIONPs at low concentrations was reflected in the traditional cell viability assay.

Hospitalisation associated with the 2009 H1N1 pandemic and seasonal influenza in Hong Kong, 2005 to 2010

Reliable estimates of the morbidity burden caused by the 2009 pandemic influenza (pH1N1) are important for assessing the severity of the pandemic. Poisson regression models were fitted to weekly numbers of cause-specific hospitalisation in Hong Kong from 2005 to 2010. Excess hospitalisation associated with the 2009 pandemic and seasonal influenza was derived from the model by incorporating the proxy variables of weekly proportions of specimens positive for the pandemic influenza A(H1N1)pdm09, seasonal influenza A (subtypes H3N2 and H1N1) and B viruses. Compared with seasonal influenza, pH1N1 influenza was associated with higher hospitalisation rates for acute respiratory disease (ARD) among children younger than 18 years and adults aged between 18 and 64 years, but among the elderly aged 65 years and older the hospitalisation rates were lower for pH1N1 than for seasonal H3N2 and H1N1 influenza. Hospitalisation rates for chronic diseases associated with pH1N1 influenza were generally higher than those associated with seasonal influenza. The reported hospitalised cases with laboratory-confirmed pandemic infections accounted for only 16% of pH1N1 influenza-associated hospitalisations for ARD in the age group 75 years and older, and 5‒66% of hospitalisations for chronic diseases in those older than 40 years. The 2009 H1N1 influenza pandemic was associated with a dramatically increased risk of hospitalisation among children and young adults. The morbidity burden of pandemic was underreported in old people and in those with chronic conditions.

Hospitalisation associated with the 2009 H1N1 pandemic and seasonal influenza in Hong Kong, 2005 to 2010

Reliable estimates of the morbidity burden caused by the 2009 pandemic influenza (pH1N1) are important for assessing the severity of the pandemic. Poisson regression models were fitted to weekly numbers of cause-specific hospitalisation in Hong Kong from 2005 to 2010. Excess hospitalisation associated with the 2009 pandemic and seasonal influenza was derived from the model by incorporating the proxy variables of weekly proportions of specimens positive for the pandemic influenza A(H1N1)pdm09, seasonal influenza A (subtypes H3N2 and H1N1) and B viruses. Compared with seasonal influenza, pH1N1 influenza was associated with higher hospitalisation rates for acute respiratory disease (ARD) among children younger than 18 years and adults aged between 18 and 64 years, but among the elderly aged 65 years and older the hospitalisation rates were lower for pH1N1 than for seasonal H3N2 and H1N1 influenza. Hospitalisation rates for chronic diseases associated with pH1N1 influenza were generally higher than those associated with seasonal influenza. The reported hospitalised cases with laboratory-confirmed pandemic infections accounted for only 16% of pH1N1 influenza-associated hospitalisations for ARD in the age group 75 years and older, and 5?66% of hospitalisations for chronic diseases in those older than 40 years. The 2009 H1N1 influenza pandemic was associated with a dramatically increased risk of hospitalisation among children and young adults. The morbidity burden of pandemic was underreported in old people and in those with chronic conditions.

Theory and action for effective condom promotion: illustrations from a behavior intervention project for sex workers in singapore

Acquired immunodeficiency virus (AIDS) and sexually transmitted diseases (STD) control programs targeted at sex workers have focused on condom use. Reasons for non-condom use among female brothel-based sex workers in Singapore were found to be low self-efficacy, lack of condom negotiation skills, and barriers such as fear of annoying clients. Green's PRECEDE framework and Bandura's self-efficacy theory were applied to develop a project aimed at equipping sex workers with negotiation skills, overcoming barriers to condom use, and gathering support from brothel keepers and peers. The experimental group showed significant improvements in negotiation skills and outcome behavior of always refusing sex without a condom, that were supported by a decline in gonorrhea incidence. This article describes the application of behavior change and health education theories to achieve reduction in gonorrhea risk.

Effect of influenza on cardiorespiratory and all-cause mortality in Hong Kong, Singapore and Guangzhou

1. Using a common modelling approach, mortality attributable to influenza was higher in the two subtropical cities Guangzhou and Hong Kong than in the tropical city Singapore. 2. The virus activity appeared more synchronised in subtropical cities, whereas seasonality of influenza tended to be less marked in the tropical city. 3. High temperature was associated with increased mortality after influenza infection in Hong Kong, whereas relative humidity was an effect modifier for influenza in Guangzhou. No effect modification was found for Singapore. 4. Seasonal and environmental factors probably play a more important role than socioeconomic factors in regulating seasonality and disease burden of influenza. Further studies are needed in identifying the mechanism behind the regulatory role of environmental factors.

How to determine life expectancy change of air pollution mortality: a time series study

BACKGROUND

Information on life expectancy (LE) change is of great concern for policy makers, as evidenced by discussions of the "harvesting" (or "mortality displacement") issue, i.e. how large an LE loss corresponds to the mortality results of time series (TS) studies. Whereas loss of LE attributable to chronic air pollution exposure can be determined from cohort studies, using life table methods, conventional TS studies have identified only deaths due to acute exposure, during the immediate past (typically the preceding one to five days), and they provide no information about the LE loss per death.

METHODS

We show how to obtain information on population-average LE loss by extending the observation window (largest "lag") of TS to include a sufficient number of "impact coefficients" for past exposures ("lags"). We test several methods for determining these coefficients. Once all of the coefficients have been determined, the LE change is calculated as time integral of the relative risk change after a permanent step change in exposure.

RESULTS

The method is illustrated with results for daily data of non-accidental mortality from Hong Kong for 1985 - 2005, regressed against PM10 and SO2 with observation windows up to 5 years. The majority of the coefficients is statistically significant. The magnitude of the SO2 coefficients is comparable to those for PM10. But a window of 5 years is not sufficient and the results for LE change are only a lower bound; it is consistent with what is implied by other studies of long term impacts.

CONCLUSIONS

A TS analysis can determine the LE loss, but if the observation window is shorter than the relevant exposures one obtains only a lower bound.

Secondhand smoke (SHS) exposures: workplace exposures, related perceptions of SHS risk, and reactions to smoking in catering workers in smoking and nonsmoking premises

INTRODUCTION

Smoke-free workplace legislation often exempts certain venues. Do smoking (exempted) and nonsmoking (nonexempted) catering premises' workers in Hong Kong report different perceptions of risk from and reactions to nearby smoking as well as actual exposure to secondhand smoke (SHS)?

METHODS

In a cross-sectional survey of 204 nonsmoking catering workers, those from 67 premises where smoking is allowed were compared with workers from 36 nonsmoking premises in Hong Kong on measures of perceptions of risk and behavioral responses to self-reported SHS exposure, plus independent exposure assessment using urinary cotinine.

RESULTS

Self-reported workplace SHS exposure prevalence was 57% (95% CI = 49%-65%) in premises prohibiting and 100% (95% CI = 92%-100%) in premises permitting smoking (p < .001). Workers in smoking-permitted premises perceived workplace air quality as poorer (odds ratio [OR] = 9.3, 95% CI = 4.2-20.9) with higher associated risks (OR = 3.7, 95% CI = 1.6-8.6) than workers in smoking-prohibited premises. Workers in smoking-prohibited premises were more bothered by (OR = 0.2, 95% CI = 0.1-0.5) and took more protective action to avoid SHS (OR = 0.2, 95% CI = 0.1-0.4) than workers in smoking-permitted premises. Nonwork exposure was negatively associated with being always bothered by nearby smoking (OR = 0.3, 95% CI = 0.1-0.9), discouraging nearby smoking (OR = 0.5, 95% CI = 0.2-1.1), and discouraging home smoking (OR = 0.4, 95% CI = 0.2-0.9). Urinary cotinine levels were inversely related to workers' avoidance behavior but positively related to their perceived exposure-related risks.

CONCLUSIONS

Different workplace smoking restrictions predicted actual SHS exposure, exposure-related risk perception, and protective behaviors. Workers from smoking-permitted premises perceived greater SHS exposure-related risks but were more tolerant of these than workers in smoking-prohibited premises. This tolerance might indirectly increase both work and nonwork exposures.

Part 5. Public health and air pollution in Asia (PAPA): a combined analysis of four studies of air pollution and mortality

BACKGROUND

In recent years, Asia has experienced rapid economic growth and a deteriorating environment caused by the increasing use of fossil fuels. Although the deleterious effects of air pollution from fossil-fuel combustion have been demonstrated in many Western nations, few comparable studies have been conducted in Asia. Time-series studies of daily mortality in Asian cities can contribute important new information to the existing body of knowledge about air pollution and health. Not only can these studies verify important health effects of air pollution in local regions in Asia, they can also help determine the relevance of existing air pollution studies to mortality and morbidity for policymaking and environmental controls. In addition, the studies can help identify factors that might modify associations between air pollution and health effects in various populations and environmental conditions. Collaborative multicity studies in Asia-especially when designed, conducted, and analyzed using a common protocol-will provide more robust air pollution effect estimates for the region as well as relevant, supportable estimates of local adverse health effects needed by environmental and public-health policymakers.

SPECIFIC OBJECTIVES

The Public Health and Air Pollution in Asia (PAPA*) project, sponsored by the Health Effects Institute, consisted of four studies designed to assess the effects of air pollution on mortality in four large Asian cities, namely Bangkok, in Thailand, and Hong Kong, Shanghai, and Wuhan, in China. In the PAPA project, a Common Protocol was developed based on methods developed and tested in NMMAPS, APHEA, and time-series studies in the literature to help ensure that the four studies could be compared with each other and with previous studies by following an established protocol. The Common Protocol (found at the end of this volume) is a set of prescriptive instructions developed for the studies and used by the investigators in each city. It is flexible enough to allow for adjustments in methods to optimize the fit of health-effects models to each city's data set. It provides the basis for generating reproducible results in each city and for meta-estimates from combined data. By establishing a common methodology, factors that might influence the differences in results from previous studies can more easily be explored. Administrative support was provided to ensure that the highest quality data were used in the analysis. It is anticipated that the PAPA results will contribute to the international scientific discussion of how to conduct and interpret time-series studies of air pollution and will stimulate the development of high-quality routine systems for recording daily deaths and hospital admissions for time-series analysis.

METHODS

Mortality data were retrieved from routine databases with underlying causes of death coded using the World Health Organization (WHO) International Classification of Diseases, 9th revision or 10th revision (ICD-9, ICD-10). Air quality measurements included nitrogen dioxide (NO2), sulfur dioxide (SO2), particulate matter with aerodynamic diameter < or = 10 microm (PM10), and ozone (O3) and were obtained from several fixed-site air monitoring stations that were located throughout the metropolitan areas of the four cities and that met the standards of procedures for quality assurance and quality control carried out by local government units in each city. Using the Common Protocol, an optimized core model was established for each city to assess the effects of each of the four air pollutants on daily mortality using generalized linear modeling with adjustments for time trend, seasonality, and other time-varying covariates by means of a natural-spline smoothing function. The models were adjusted to suit local situations by correcting for influenza activity, autocorrelation, and special weather conditions. Researchers in Hong Kong, for example, used influenza activity based on frequency of respiratory mortality; researchers in Hong Kong and Shanghai used autoregressive terms for daily outcomes at lag days; and researchers in Wuhan used additional smoothing for periods with extreme weather conditions.

RESULTS AND DISCUSSION

For mortality due to all natural (nonaccidental) causes at all ages, the effects of air pollutants per 10-microg/m3 increase in concentration was found to be higher in Bangkok than in the three Chinese cities, with the exception of the effect of NO2 in Wuhan. The magnitude of the effects for cardiovascular and respiratory mortality were generally higher than for all natural mortality at all ages. In addition, the effects associated with PM10 and O3 in all natural, cardiovascular; and respiratory mortality were found to be higher in Bangkok than in the three Chinese cities. The explanation for these three findings might be related to consistently higher daily mean temperatures in Bangkok, variations in average time spent outdoors by the susceptible populations, and the fact that less air conditioning is available and used in Bangkok than in the other cities. However, when pollutant concentrations were incorporated into the excess risk estimates through the use of interquartile range (IQR), the excess risk was more comparable across the four cities. We found that the increases in effects among older age groups were greater in Bangkok than in the other three cities. After excluding data on extremely high concentrations of PM10 in Bangkok, the effect estimate associated with PM10 concentrations decreased in Bangkok (suggesting a convex relationship between risk and PM10, where risk levels off at high concentrations) instead of increasing, as it did in the other cities. This leveling off of effect estimates at high concentrations might be related to differences in vulnerability and exposure of the population to air pollution as well as to the sources of the air pollutant. IMPLICATIONS OF THE STUDY: The PAPA project is the first coordinated Asian multicity air pollution study ever published; this signifies the beginning of an era of cooperation and collaboration in Asia, with the development of a common protocol for coordination, data management, and analysis. The results of the study demonstrated that air pollution in Asia is a significant public health burden, especially given the high concentrations of pollutants and high-density populations in major cities. When compared with the effect estimates reported in the research literature of North America and Western Europe, the study's effect estimates for PM10 were generally similar and the effect estimates for gaseous pollutants were relatively higher. In Bangkok, however, a tropical city where total exposures to outdoor pollution might be higher than in most other cities, the observed effects were greater than those reported in the previous (i.e., Western) studies. In general, the results suggested that, even though social and environmental conditions across Asia might vary, it is still generally appropriate to apply to Asia the effect estimates for other health outcomes from previous studies in the West. The results also strongly support the adoption of the global air quality guidelines recently announced by WHO.

Spatial clustering of SARS in Hong Kong

1. Geographic information system (GIS) can be applied during an acute infectious disease outbreak to reveal new geospatial information in addition to standard field epidemiological analyses. 2. When applied in real time during the onset and evolution of an epidemic, GIS can monitor and enhance understanding of the transmission dynamics of an infectious agent, thereby facilitating the design, implementation and evaluation of potential intervention strategies.

Influenza-associated hospitalisation

The disease burden associated with influenza includes not only acute respiratory diseases but also cerebrovascular disease, ischaemic heart disease and diabetes mellitus.

Adult pyloric stenosis masquerading as acute renal failure

Gastric outlet obstruction and in particular, pyloric stenosis, is relatively common in developing countries. Acute clinical presentation is often the manifestation of biochemical and electrolyte changes. The presence of metabolic alkalosis in combination with acute renal failure should alarm us to the possibility of adult pyloric stenosis. We report a case of adult pyloric stenosis that presented as acute renal failure and discuss its pathophysiology.

A review of effects of particulate matter-associated nickel and vanadium species on cardiovascular and respiratory systems

Many epidemiological investigations indicate that excess risks of mortality and morbidity may vary among specific PM(2.5) components. Nickel (Ni) and vanadium (V) particulate metal species may potentially be related to increasing respiratory and cardiovascular mortality and morbidity. This review focuses on exposure concentrations of these two species in various settings, their health effects based on epidemiological and toxicological studies and the underlying mechanisms. The evidence shows that environmental exposure concentrations of Ni and V in general setting are lower than the World Health Organization standard (V, 1 microg/m(3)/day) in 2000, or the European Environment Agency standard (Ni, 1 microg/m(3)/day) in 2003, but their associations with cardiopulmonary diseases can still be found. The toxicological mechanism can be explained by laboratory-based studies. Updated safe guidelines on environmental and human exposure of Ni and V are necessary in order to clarify the associations between them and cardiopulmonary diseases and provide environmental intervention policies.

Grossly delayed graft function in a living related kidney transplant recipient: a case report

Delayed graft function is a potentially challenging problem especially in cadaveric kidney transplant recipients. It adversely impacts long-term graft survival. It is rarely seen in living kidney transplants. Recovery of graft function usually occurs within a month. The chances of recovery of graft function diminish with further prolongation of delayed function. In fact, recovery of graft function after 3 months has rarely been described, we report herein recovery of graft function after 132 days of nonfunction in a living related kidney transplant.

Raloxifene protects endothelial cell function against oxidative stress

BACKGROUND AND PURPOSE

Maintaining a delicate balance between the generation of nitric oxide (NO) and removal of reactive oxygen species (ROS) within the vascular wall is crucial to the physiological regulation of vascular tone. Increased production of ROS reduces the effect and/or bioavailability of NO, leading to an impaired endothelial function. This study tested the hypothesis that raloxifene, a selective oestrogen receptor modulator, can prevent endothelial dysfunction under oxidative stress.

EXPERIMENTAL APPROACH

Changes in isometric tension were measured in rat aortic rings. The content of cyclic GMP in aortic tissue was determined by radioimmunoassay. Phosphorylation of endothelial NOS (eNOS) and Akt was assayed by Western blot analysis.

KEY RESULTS

In rings with endothelium, ACh-induced relaxations were attenuated by a ROS-generating reaction (hypoxanthine plus xanthine oxidase, HXXO). The impaired relaxations were ameliorated by acute treatment with raloxifene. HXXO suppressed the ACh-stimulated increase in cyclic GMP levels; this effect was antagonized by raloxifene. The improved endothelial function by raloxifene was abolished by ICI 182,780, and by wortmannin or LY294002. Raloxifene also protected endothelial cell function against H2O2. Raloxifene increased the phosphorylation of eNOS at Ser-1177 and Akt at Ser-473; this effect was blocked by ICI 182,780. Finally, raloxifene was not directly involved in scavenging ROS, and neither inhibited the activity of xanthine oxidase nor stimulated that of superoxide dismutase.

CONCLUSION AND IMPLICATIONS

Raloxifene is effective against oxidative stress-induced endothelial dysfunction in vitro through an ICI 182,780-sensitive mechanism that involves the increased phosphorylation and activity of Akt and eNOS in rat aortae.

Fentanyl dose?response curves when inserting the LMA Classic?laryngeal mask airway

Probit analysis was used to predict an optimal dose of fentanyl, co-administered with propofol 2.5 mg.kg(-1), when inserting the laryngeal mask airway. In all, 21 male and 54 female healthy Chinese patients, aged 18-63 years, requiring anaesthesia for minor surgery were recruited. They were assigned to one of five groups: placebo, 0.5, 1.0, 1.5 and 2.0 microg.kg(-1). Insertion was performed 90 s after administration and insertion conditions assessed using a six-category score. Dose-response curves could only be drawn for swallowing and movement categories, and only the ED(50) could be predicted with certainty. To provide optimal conditions in over 95% of patients, fentanyl doses well above the clinical range were required. A standard fentanyl dose of 1 mug.kg(-1), co-administered with propofol 2.5 mg.kg(-1), provided optimal conditions in 65% of cases. Ninety seconds may have been insufficient time for fentanyl to reach its peak effect.

Non-invasive measurement of reduced ventilation:perfusion ratio and shunt in infants with bronchopulmonary dysplasia: a physiological definition of the disease

BACKGROUND

An objective definition of bronchopulmonary dysplasia (BPD) is required to interpret trial outcomes and provide a baseline for prognostic studies. Current definitions do not quantify disease severity. The cardinal measures of impaired gas exchange are a reduced ventilation:perfusion ratio (V(A):Q) and increased right to left shunt. These can be determined non-invasively by plotting arterial oxygen saturation (Spo(2)) against inspired oxygen pressure (PIo(2)).

AIMS

To describe the reduced V(A):Q and shunt in infants with BPD and evaluate these as graded measures of pulmonary dysfunction.

METHODS

21 preterm infants with BPD were studied. PIo(2) was changed stepwise to vary Spo(2) between 86% and 94%. Pairs of PIo(2) and Spo(2) data points for each infant were plotted and analysed to derive reduced V(A):Q ratio and shunt.

RESULTS

In every infant, the Spo(2) versus PIo(2) curve was shifted to the right of the normal because of a reduced V(A):Q. The mean (SD) shift was 16.5 (4.7) kPa (normal 6 kPa). Varying degrees of shunt were also present, but these were less important in determining Spo(2) within the studied range. The degree of shift was strongly predictive of the PIo(2) required to achieve any Spo(2) within the range 86-94% (R(2)>0.9), permitting shift and V(A):Q to be determined from a single pair of PIo(2) and SpO(2) values in this range.

CONCLUSIONS

The predominant gas exchange impairment in BPD is a reduced V(A):Q, described by the right shift of the Spo(2) versus PIo(2) relationship. This provides a simpler method for defining BPD, which can grade disease severity.

Association between air pollution and general practitioner visits for respiratory diseases in Hong Kong

BACKGROUND

Few studies have explored the relation between air pollution and general practitioner (GP) consultations in Asia. Clinic attendance data from a network of GPs were studied, and the relationship between daily GP consultations for upper respiratory tract infections (URTI) and non-URTI respiratory diseases and daily air pollutant concentrations measured in their respective districts was examined.

METHODS

A time series study was performed in 2000-2002 using data on daily patient consultations in 13 GP clinics distributed over eight districts. A Poisson regression model was constructed using the generalised additive model approach for each GP clinic, and associations with daily numbers of first visits for URTI were sought for daily concentrations of the following air pollutants: SO(2), NO(2), O(3), PM(10,) and PM(2.5). A summary relative risk of first visits to the GP for URTI per unit increase in concentration for each air pollutant was derived using a random effect model. First visits for non-URTI respiratory diseases were analysed in three GP clinics.

RESULTS

Significant associations were observed between first visits for URTI and an increase in the concentrations of NO(2), O(3), PM(10), and PM(2.5). The excess risk was highest for NO(2) (3.0%), followed by O(3) (2.5%), PM(2.5) (2.1%), and PM(10) (2.0%). Similar associations with these air pollutants were found for non-URTI respiratory diseases.

CONCLUSIONS

These results provide further evidence that air pollution contributes to GP visits for URTI and non-URTI respiratory diseases in the community.

Factors related to non-participation in physical activity among the students in Hong Kong

The patterns and determinants of physical inactivity among the Chinese youths are unknown. This study assessed the prevalence and predictors of physical inactivity among students in a Hong Kong university. A cross-sectional survey of year 1 and year 3 Chinese undergraduate students in 1997, using a structured, self-administered questionnaire was carried out. Questionnaires were returned by 64 % (1189/1849) of the students. Thirty-one percent of the respondents did not participate in physical activity. Being female, not a university resident, studying in the Faculty of Arts and rating current health status as poor or very poor were predictors of physical inactivity. No time and no interest were the most common reasons for non-participation in physical activity among the students. This study showed that about one-third of Chinese university students are physically inactive and would gain health benefits from organized intervention. Awareness among the students about the risks of physical inactivity should be enhanced and efforts made to increase physical activity should be reinforced. Factors identified as predictors of physical inactivity should be taken into account in the design of intervention.

Understanding the spatial clustering of severe acute respiratory syndrome (SARS) in Hong Kong

We applied cartographic and geostatistical methods in analyzing the patterns of disease spread during the 2003 severe acute respiratory syndrome (SARS) outbreak in Hong Kong using geographic information system (GIS) technology. We analyzed an integrated database that contained clinical and personal details on all 1,755 patients confirmed to have SARS from 15 February to 22 June 2003. Elementary mapping of disease occurrences in space and time simultaneously revealed the geographic extent of spread throughout the territory. Statistical surfaces created by the kernel method confirmed that SARS cases were highly clustered and identified distinct disease "hot spots." Contextual analysis of mean and standard deviation of different density classes indicated that the period from day 1 (18 February) through day 16 (6 March) was the prodrome of the epidemic, whereas days 86 (15 May) to 106 (4 June) marked the declining phase of the outbreak. Origin-and-destination plots showed the directional bias and radius of spread of superspreading events. Integration of GIS technology into routine field epidemiologic surveillance can offer a real-time quantitative method for identifying and tracking the geospatial spread of infectious diseases, as our experience with SARS has demonstrated.

The use of freeze-dry bovine pericardium (FDBP) in diaphragmatic herniorrhaphy in dogs

A study was conducted to investigate the effectiveness of freeze-dried bovine pericardium (FDBP) as a biomaterial in diaphragmatic herniorrhapy in dogs. Eight adult dogs were randomly selected and divided into two equal groups. In FDBP group, a diaphragmatic defect was induced and repaired with an identical size of FDBP. In the control group, a diaphragmatic wall was incised at three-side border creating a flap and sutured. Grossly, only mild intrathoracic adhesion was observed for most of the animals, and no herniation occured. Microscopically, the biomaterial incorporated into the host's tissue by ingrowth of young muscle fiber and massive new blood vessel formation in between the fibrous tissue.

Binary latent variable modelling and its applicationin the study of air pollution in Hong Kong

A binary latent variable is constructed to account for the correlation between multiple binary outcomes and is treated as a dependent variable in modelling for covariate effects. This modelling method is similar to the structural equation modelling. Three models are considered: (1) all covariates affecting the binary latent variable directly; (2) some covariates affecting the binary latent variable while other affecting the manifestation of the binary outcomes; and (3) no covariates are included. Gibbs sampling, a special case of the Markov Chain Monte Carlo method, is used to estimate the parameters in the models. Simulation studies show that this method is valid and reliable in estimating covariate effects. But Model (1) fitted the data best with lowest value in the deviance information criteria. The method is illustrated by applying it to the data analysis of an environmental air pollution study. The results show that air pollution (i.e. the most versus the least polluted district) (odds ratio 1.20; 95% confidence interval 0.97-1.49; p=0.102), smoking (relative to not smoking) (2.75; 2.21-3.41; p < 0.001) and mosquito coil use (relative to non-use) (1.27; 0.99-1.62; p=0.058) had an impact on the respiratory health of male adults in Hong Kong.

Evaluation of the 1992-1999 World Bank Schistosomiasis Control Project in China

The 1992-1999 World Bank Schistosomiasis Control Project in China contributed significantly to the disease control with its specific strategy and approach. An evaluation was made in this paper based on project control and surveillance data collected from all project provinces systematically year by year. Several indicators were computed, comparison was made using the 1989 survey data as the baseline, and correlation analysis was carried out on prevalence in humans, prevalence in cattle and buffaloes and infection rate of snails. From 1992 to 1998, the overall prevalence in human population, prevalence in children aged 7-14 and prevalence in cattle and buffaloes decreased by 5.74, 59.55 and 62.30%, respectively. Snail areas increased by 14.85% throughout the project period, while snail infection rate and density of infected snails decreased by 68.75 and 44.95%. Hubei province was among all eight provinces the most impressive in schistosomiasis control during the project. Results show that coverage of chemotherapy was among other factors the most directly-related to the prevalence in humans. The drug for chemotherapy-praziquantel was effective for new cases rather than reinfection. As to the overall achievement, most of the objectives set for the project had been achieved, especially the decrease in prevalence, in both human population and cattle and buffaloes. However, the achievement of snail control was not so ideal, which calls for rectification for a more applicable and practical strategy of snail control in China.

As time goes by

The timing of birth-related events may influence neonatal outcome and is often pivotal in medicolegal cases. This prospective observational study determined the variation in displayed time on timepieces in a regional maternity unit which could result in inaccuracies of time documentation. The mean (95% CI) difference between time displayed and true time was sec (+/- 2 min 4 sec) for delivery room clocks and +1 m 8 s (+/- 7 m 12 s) for resuscitation room clocks. The maximum discrepancy between delivery room and resuscitation room clocks was 7 m 52 s. The abilities of staff to estimate the duration of time passed was also assessed. The mean (95% CI) five-minute estimate was 4 m 52 s (+/- 3 m 12 s). These disparities could have considerable medicolegal significance, and should be taken into consideration in risk management studies. Maternity units should move towards synchronising all timepieces. Meanwhile, statements about the precise timing of events should be regarded with suspicion.