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The effect of the mechanical micro-environment on spinal cord injury (SCI) and treatment effectiveness remains unclear. Currently, there are limited imaging methods that can directly assess the localized mechanical behavior of spinal cords in vivo. In this study, we apply new ultrasound elastography (USE) techniques to assess SCI in vivo at the site of the injury and at the time of one week post injury, in a rabbit animal model. Eleven rabbits underwent laminectomy procedures. Among them, spinal cords of five rabbits were injured during the procedure. The other six rabbits were used as control. Two neurological statuses were achieved: non-paralysis and paralysis. Ultrasound data were collected one week post-surgery and processed to compute strain ratios. Histologic analysis, mechanical testing, magnetic resonance imaging (MRI), computerized tomography and MRI diffusion tensor imaging (DTI) were performed to validate USE results. Strain ratios computed via USE were found to be significantly different in paralyzed versus non-paralyzed rabbits. The myelomalacia histologic score and spinal cord Young's modulus evaluated in selected animals were in good qualitative agreement with USE assessment. It is feasible to use USE to assess changes in the spinal cord of the presented animal model. In the future, with more experimental data available, USE may provide new quantitative tools for improving SCI diagnosis and prognosis. [ABSTRACT FROM AUTHOR]

The effect of the mechanical micro-environment on spinal cord injury (SCI) and treatment effectiveness remains unclear. Currently, there are limited imaging methods that can directly assess the localized mechanical behavior of spinal cords in vivo. In this study, we apply new ultrasound elastography (USE) techniques to assess SCI in vivo at the site of the injury and at the time of one week post injury, in a rabbit animal model. Eleven rabbits underwent laminectomy procedures. Among them, spinal cords of five rabbits were injured during the procedure. The other six rabbits were used as control. Two neurological statuses were achieved: non-paralysis and paralysis. Ultrasound data were collected one week post-surgery and processed to compute strain ratios. Histologic analysis, mechanical testing, magnetic resonance imaging (MRI), computerized tomography and MRI diffusion tensor imaging (DTI) were performed to validate USE results. Strain ratios computed via USE were found to be significantly different in paralyzed versus non-paralyzed rabbits. The myelomalacia histologic score and spinal cord Young's modulus evaluated in selected animals were in good qualitative agreement with USE assessment. It is feasible to use USE to assess changes in the spinal cord of the presented animal model. In the future, with more experimental data available, USE may provide new quantitative tools for improving SCI diagnosis and prognosis. [ABSTRACT FROM AUTHOR]

Ephedrae Herba (Ephedra), known as "MaHuang" in China, is the dried straw stem that is associated with the lung and urinary bladder meridians. At present, more than 60 species of Ephedra plants have been identified, which contain more than 100 compounds, including alkaloids, flavonoids, tannins, sugars, and organic phenolic acids. This herb has long been used to treat asthma, liver disease, skin disease, and other diseases, and has shown unique efficacy in the treatment of COVID-19 infection. Because alkaloids are the main components causing toxicity, the safety of Ephedra must be considered. However, the nonalkaloid components of Ephedra can be effectively used to replace ephedrine extracts to treat some diseases, and reasonable use can ensure the safety of Ephedra. We reviewed the phytochemistry, pharmacology, clinical application, and alkaloid toxicity of Ephedra, and describe prospects for its future development to facilitate the development of Ephedra. [ABSTRACT FROM AUTHOR]

The healing of large bone defects has been investigated for decades due to its complexity and clinical relevance. Ultrasound (US) methods have shown promise in monitoring bone healing, but no quantitative method to assess regenerated bone morphology in US images has been presented yet. In this study, we investigate new US morphometric parameters to quantify bone regeneration in vivo. A segmental tibial defect was surgically created and stabilized in a sheep animal model. US and computed tomography (CT) imaging data were collected two months post-surgery. New bone was assessed, reconstructed and quantified from the US and CT data using 3 morphometric parameters: the new-bone bulk (NBB), new-bone surface (NBS) and new-bone contact (NBC). The distance (mm) between surface reconstructions from repeated US was 0.49 ± 0.30 and from US and CT was 0.89 ± 0.49 . In the mid-shaft of the defected tibia, US measurements of NBB, NBS and NBC were significantly higher than the corresponding CT measurements ( p < 0.001 ). Based on our results, we conclude that US may complement CT to reconstruct and quantify bone regrowth, especially in its early stages. [ABSTRACT FROM AUTHOR]

This study reports the first use of ultrasound (US) elastography for imaging spinal fractures by assessing the mechanical response of the soft tissue at the posterior vertebra boundary to a uniaxial compression in rabbit ex vivo samples. Three-dimensional finite-element (FE) models of the vertebra-soft tissue complex in rabbit samples are generated and analyzed to evaluate the distribution of the axial normal and shear strains at the vertebra-soft tissue interface. Experiments on the same samples are performed to corroborate simulation findings. Results of this study indicate that the distribution of the axial strains manifests as distinct patterns around intact and fractured vertebrae. Numerical characteristics of the axial strain’s spatial distribution are further used to construct two shape descriptors to make inferences on spinal abnormalities: 1) axial normal strain asymmetry for assessing the presence of fractures and 2) principal orientation of axial shear strain concentration regions (shear zones) for measurement of spinous process dislocation. This study demonstrates that axial normal strain and axial shear strain maps obtained via US elastography can provide a new means to detect spine fractures and abnormalities in the selected ex vivo animal models. Spinal fracture detection is important for the assessment of spinal cord injuries and stability. However, identification of spinal fractures using US is currently challenging. Our results show that features resulting from strain elastograms can serve as a useful adjunct to B-mode images in identifying spine fractures in the selected animal samples, and this information could be helpful in clinical settings. [ABSTRACT FROM AUTHOR]

Alterations of Young's modulus (YM) and Poisson's ratio (PR) in biological tissues are often early indicators of the onset of pathological conditions. Knowledge of these parameters has been proven to be of great clinical significance for the diagnosis, prognosis and treatment of cancers. Currently, however, there are no non-invasive modalities that can be used to image and quantify these parameters in vivo without assuming incompressibility of the tissue, an assumption that is rarely justified in human tissues. In this paper, we developed a new method to simultaneously reconstruct YM and PR of a tumor and of its surrounding tissues based on the assumptions of axisymmetry and ellipsoidal-shape inclusion. This new, non-invasive method allows the generation of high spatial resolution YM and PR maps from axial and lateral strain data obtained via ultrasound elastography. The method was validated using finite element (FE) simulations and controlled experiments performed on phantoms with known mechanical properties. The clinical feasibility of the developed method was demonstrated in an orthotopic mouse model of breast cancer. Our results demonstrate that the proposed technique can estimate the YM and PR of spherical inclusions with accuracy higher than 99% and with accuracy higher than 90% in inclusions of different geometries and under various clinically relevant boundary conditions. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to determine reference values for oxygen saturation (SpO2 ) in neonates at mild and moderate altitudes.Methods: Our study included 41 097 consecutively born, asymptomatic neonates from 35 hospitals, located in Yunnan, China, with altitudes ranging from 267 to 2202 m. Pre-and post-ductal SpO2 of each neonate was measured at 24 hours of age and before hospital discharge. All study participants, according to the altitude of birth, were categorised into three groups: low (0-500 m), mild (500-1500 m) and moderate altitude (1500-2500 m).Results: Every 1000-m increase in altitude was associated with a 1.54 per cent decrease in mean SpO2 . The means of pre-ductal SpO2 at low, mild and moderate groups were 97.9%, 96.4% and 95.5%, respectively. We used the 2.5th percentile of SpO2 distribution as the cut-off for neonatal SpO2 screening and defined new cut-off values of ≤93% for mild altitudes, ≤92% for moderate altitudes and no adjustment for low altitudes.Conclusion: We recommend revised cut-off values for neonatal SpO2 at mild and moderate altitudes and provide new values for paediatricians to refer to when screening neonates for severe congenital heart or lung diseases. [ABSTRACT FROM AUTHOR]

Background: Crowdsourcing method is an excellent tool for developing tailored interventions to improve sexual health. We evaluated the implementation of an innovation contest for sexual health promotion in China.Methods: We organized an innovation contest over three months in 2014 for Chinese individuals < 30 years old to submit images for a sexual health promotion campaign. We solicited entries via social media and in-person events. The winning entry was adapted into a poster and distributed to STD clinics across Guangdong Province. In this study, we evaluated factors associated with images that received higher scores, described the themes of the top five finalists, and evaluated the acceptability of the winning entry using an online survey tool.Results: We received 96 image submissions from 76 participants in 10 Chinese provinces. Most participants were youth (< 25 years, 85%) and non-professionals (without expertise in medicine, public health, or media, 88%). Youth were more likely to submit high-scoring entries. Images from professionals in medicine, public health, or media did not have higher scores compared to images from non-professionals. Participants were twice as likely to have learned about the contest through in-person events compared to social media. We adapted and distributed the winning entry to 300 STD clinics in 22 cities over 2 weeks. A total of 8338 people responded to an acceptability survey of the finalist entry. Among them, 79.8% endorsed or strongly endorsed being more willing to undergo STD testing after seeing the poster.Conclusions: Innovation contests may be useful for soliciting images as a part of comprehensive sexual health campaigns in low- and middle-income countries. [ABSTRACT FROM AUTHOR]

The inter-fragmentary gap size (IFGS) is a critical factor affecting the propensity of bone healing. In this paper, we present a study to analyze ultrasound strain elastographic numerical features in samples with distinct IFGS using both simulations and experiments. Six fractured rabbit hind leg samples in total were used in this study with controlled IFGS of 1 mm, 5 mm and 1 cm. For the simulation, computed tomography (CT) scans of all six samples were used to create solid models. Finite element analysis (FEA) and subsequent elastography simulations were performed on the 3D models to produce tensorial strain field data. Features of bony fragment separation were defined on different strain components and computed for strains segmented at varying thresholds to evaluate their performance in estimating the IFGS. A threshold for each strain component was then determined, based on which extra 3D features of interest were defined and extracted from the segmented strain data. Then, all 3D features were compared statistically among the three nominal groups. Additional simulations and experiments of axial shear strain elastography (ASSE) on the median coronal plane of the same samples were also performed. Our results indicate that coronal plane axial shear (CPAS) strain elastography produces a separation feature which is statistically correlated with the IFGS, and that our elastography simulation module is effective in predicting the CPAS elastographic strain behavior for different IFGS. [ABSTRACT FROM AUTHOR]

The mechanical behavior of long bones and fractures has been under investigation for many decades due to its complexity and clinical relevance. In this paper, we report a new subject-specific methodology to predict and analyze the mechanical behavior of the soft tissue at a bone interface with the intent of identifying the presence and location of bone abnormalities with high accuracy, spatial resolution, and contrast. The proposed methodology was tested on both intact and fractured rabbit femur samples with finite element-based 3-D simulations, created from actual femur computed tomography data, and ultrasound elastography experiments. The results included in this study demonstrate that elastographic strains at the bone/soft tissue interface can be used to differentiate fractured femurs from the intact ones on a distribution level. These results also demonstrate that coronal plane axial shear strain creates a unique contrast mechanism that can be used to reliably detect fractures (both complete and incomplete) in long bones. Kruskal–Wallis test further demonstrates that the contrast measure for the fracture group (simulation: 2.1286±0.2206; experiment: 2.7034 ± 1.0672) is significantly different from that for the intact group (simulation: 0 ± 0; experiment: 1.1540±0.6909) when using coronal plane axial shear strain elastography ($p$ < 0.01). We conclude that: 1) elastography techniques can be used to accurately identify the presence and location of fractures in a long bone and 2) the proposed model-based approach can be used to predict and analyze strains at a bone fracture site and to better interpret experimental elastographic data. [ABSTRACT FROM AUTHOR]

A fast and robust image registration algorithm for high-dimensional brain Magnetic Resonance images was developed based on the statistical deformation models (SDMs). This model learns deformation fields and achieves fast and robust registration by greatly reducing transformation dimensionality. This model is trained via principal component analysis (PCA), which suffers from large transformation dimensionality and small samples. For the high-dimensional image registration, the dimensions of the deformation fields are huge, the basic functions computed from PCA cannot represent deformation fields well. Therefore, we proposed a local SDM (LSDM) in this paper to solve the aforementioned problems. We divided the images into several small parts, in which the dimensions of the deformation fields are greatly reduced. Then, we trained the LSDM using the deformation fields between sample images and a selected template by applying PCA in each small part. Given that the dimension of eigenvectors of LSDM decreases much more than that of SDM, the orthonormal basis functions of LSDM represent the deformation fields more accurately than those of SDM. We obtained the total deformation fields for warping the image by integrating the deformation fields of all LSDMs. Using the manually labeled MR images of different people, we demonstrated that LSDM could greatly reduce the image registration time while maintaining favorable registration accuracy. [ABSTRACT FROM AUTHOR]

Background: Recreational drug use has increased considerably among Chinese men who have sex with men (MSM). The phenomenon has the potentially to increase HIV transmission among Chinese MSM. The aims of this study were: 1) to investigate the prevalence of recreational drug use among Chinese MSM, and 2) to explore the correlation between gay smartphone based sex-seeking applications (gay apps), HIV/STIs testing, group sex, commercial sex, sexual roles and poppers use among Chinese MSM. Methods: MSM who were born biologically male, were at least 16 years of age and had engaged in anal sex with a man at least once were recruited through a nation-wide online survey in 2014. Information regarding socio-demographics, risk behaviors, recreational drug use, HIV and other STIs testing history and gay app use were collected. Univariate and multivariate analysis were used to determine factors associated with recreational drug use among Chinese MSM. Results: Among 1424 participating MSM, 1100 (77.3%) reported ever using recreational drugs in their lifetime. In the last 12 months, 303 (21.3%) used poppers, 34 (2.4%) used crystal meth and 15 (1.0%) used ecstasy. The mean age of respondents was 25.6±6.8 years, 72.9% identified as gay, 41.3% were students, and 83.8% had never been married. Multiple logistic regression models revealed that compared with non-popper users, popper users were more likely to have been tested for HIV (adjusted OR (aOR) = 1.50, 95% CI: 1.15–1.96) and other STIs (aOR = 1.65, 95% CI: 1.26–2.17). In addition, popper users were more likely to engage in group sex (aOR = 2.63, 95% CI:1.80–3.86), commercial sex (aOR = 1.86, 95% CI:1.13–3.06) and used gay mobile apps to seek sexual partners (aOR = 2.10, 95% CI:1.58–2.80). Conclusion: Chinese MSM has a high rate of recreational drug use, including poppers. Public health programs serving MSM may consider integrating intervention programs to decrease recreational drug use related harms. [ABSTRACT FROM AUTHOR]

Introduction: China is amidst a sexual revolution, with changing sexual practices and behaviors. Sex–seeking mobile phone applications (gay apps) that allow multiple people to meet up quickly may facilitate group sex. This study was therefore undertaken to evaluate group sex among Chinese MSM and to better understand factors associated with group sex. Methods: An online survey was conducted from September-October 2014, collecting data on socio-demographics, sexual behaviors, use of gay apps and occurrence of group sex among Chinese MSM. Univariate and multivariable logistic regressions were used to compare group sex and non-group sex participants. Results: Of the 1,424 MSM, the majority were under 30 years old (77.5%), unmarried (83.9%), and were gay apps users (57.9%). Overall, 141 (9.9%) participants engaged in group sex in the last 12 months. Multivariate analyses showed that men living with HIV, engaged in condomless anal intercourse with men, and used gay apps were more likely to engage in group sex, with adjusted ORs of 3.74 (95% CI 1.92–7.28), 2.88 (95% CI 2.00–4.16) and 1.46 (95% CI: 1.00–2.13), respectively. Among gay app users, the likelihood of group sex increases with the number of sex partners and the number of sex acts with partners met through a gay app. Conclusions: Chinese MSM who engage in group sex are also more likely to engage in other risky sexual behaviors, and gay app use may facilitate group sex. Further research is needed among MSM who engage in group sex in order to target interventions and surveillance. [ABSTRACT FROM AUTHOR]

Background: HIV prevalence has increased rapidly among men who have sex with men (MSM) in China reaching alarmingly high levels in some cities. Bisexual MSM have potential to transmit HIV and syphilis to their female partners through condomless vaginal intercourse (CVI). Thus, estimation of the burden of CVI and identification of its associates seemed necessary to control this cross-gender transmission. Method: In a cross-sectional study, using respondent-driven-sampling and snowball sampling, 2958 MSM were recruited from seven Chinese cities, interviewed and tested for HIV and syphilis. Descriptive analysis of the socio-demographic and behaviors followed by simple and multiple logistic regressions [adjusted for income, city, race and social network size to determine adjusted odds ratio (aOR)] were performed using SAS-9.1. Results: Among participating MSM, 19.03% were engaged in CVI. Prevalence of HIV and syphilis among participants involved in CVI were 5.86% and 14.74% respectively. MSM who were older [aOR for aged 40–49 = 2.60 (95% CI: 1.54–4.37)], married [aOR = 6.13 (4.95–7.58)], attended primary school or below [aOR = 3.86 (2.26–6.69)], met male partners at spa/bathhouse/sauna/massage parlor [aOR = 3.52 (2.62–4.72)] and had heterosexual orientation [aOR = 13.81 (7.14–26.70)] were more likely to have CVI. Furthermore, correct knowledge regarding HIV [aOR = 0.70 (0.55, 0.88)] and exposure to HIV prevention interventions [aOR = 0.67 (0.54, 0.82)] were negatively associated with CVI. Conclusions: CVI was found to be common among MSM in China. To minimize the transmission of HIV and syphilis from bisexual MSM to their relatively female partners, targeted interventions should specifically focus on bisexual MSM especially the older and married subgroups. [ABSTRACT FROM AUTHOR]

• Multi-input convolutional neural network for robust surface detection • Pose estimation integrated with spatial calibration for accurate tracking of ultrasound scans • First 3-D rendering of the full lumbar spine surface from free-hand untracked ultrasound scans using a rabbit animal model in vivo Three-dimensional (3-D) reconstruction of the spine surface is of strong clinical relevance for the diagnosis and prognosis of spine disorders and intra-operative image guidance. In this paper, we report a new technique to reconstruct lumbar spine surfaces in 3-D from non-invasive ultrasound (US) images acquired in free-hand mode. US images randomly sampled from in vivo scans of 9 rabbits were used to train a U-net convolutional neural network (CNN). More specifically, a late fusion (LF)-based U-net trained jointly on B-mode and shadow-enhanced B-mode images was generated by fusing two individual U-nets and expanding the set of trainable parameters to around twice the capacity of a basic U-net. This U-net was then applied to predict spine surface labels in in vivo images obtained from another rabbit, which were then used for 3-D spine surface reconstruction. The underlying pose of the transducer during the scan was estimated by registering stacks of US images to a geometrical model derived from corresponding CT data and used to align detected surface points. Final performance of the reconstruction method was assessed by computing the mean absolute error (MAE) between pairs of spine surface points detected from US and CT and by counting the total number of surface points detected from US. Comparison was made between the LF-based U-net and a previously developed phase symmetry (PS)-based method. Using the LF-based U-net, the averaged number of US surface points across the lumbar region increased by 21.61% and MAE reduced by 26.28% relative to the PS-based method. The overall MAE (in mm) was 0.24 ± 0.29. Based on these results, we conclude that: 1) the proposed U-net can detect the spine posterior arch with low MAE and large number of US surface points and 2) the newly proposed reconstruction framework may complement and, under certain circumstances, be used without the aid of an external tracking system in intra-operative spine applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: In this paper, an effective method is developed to extract coronary vessels from X-ray digital subtraction angiography (DSA). Unlike the traditional image subtraction technique, we used the independent component analysis (ICA) to separate the coronary vessels and backgrounds. Experimental results indicate that the proposed method can achieve better performance than the traditional subtraction technique and the segmentation method. [Copyright &y& Elsevier]

Abstract: A brain image registration algorithm, referred to as RABBIT, is proposed to achieve fast and accurate image registration with the help of an intermediate template generated by a statistical deformation model. The statistical deformation model is built by principal component analysis (PCA) on a set of training samples of brain deformation fields that warp a selected template image to the individual brain samples. The statistical deformation model is capable of characterizing individual brain deformations by a small number of parameters, which is used to rapidly estimate the brain deformation between the template and a new individual brain image. The estimated deformation is then used to warp the template, thus generating an intermediate template close to the individual brain image. Finally, the shape difference between the intermediate template and the individual brain is estimated by an image registration algorithm, e.g., HAMMER. The overall registration between the template and the individual brain image can be achieved by directly combining the deformation fields that warp the template to the intermediate template, and the intermediate template to the individual brain image. The algorithm has been validated for spatial normalization of both simulated and real magnetic resonance imaging (MRI) brain images. Compared with HAMMER, the experimental results demonstrate that the proposed algorithm can achieve over five times speedup, with similar registration accuracy and statistical power in detecting brain atrophy. [Copyright &y& Elsevier]

In China, one of the major problems in upgrading rural health services is the difficulty of communicating between the rural and urban areas. Enabling local agencies to access the Internet in resource-poor areas can provide an efficient means of diffusing current training and information and will have far-reaching policy implications. To test the feasibility of using the Internet to deliver needed health information to the countryside, the UCLA School of Public Health and the Institute of Health Studies of Kunming Medical College (IHS-KMC) collaborated in an experimental website project to improve the quality of reproductive health services to promote women's health in three rural counties of Yunnan. The project involved the county government and the Bureau of Public Health, the Bureau of Family Planning; the Bureau of Education, Women's Federation, and the Maternal and Child Health Station targeting village health workers and teachers; women's cadres. Three counties, matched on socioeconomic status, participated in the study and were randomized to receive three programs. Nanhua County received computer skill training and logistic support including a planning workshop for information diffusion. Mouding County received computers only. Dayao, the control county, did not receive the full program until the conclusion of the project. The study demonstrated that the use of a website to disseminate health information in remote rural areas is not only feasible but that it also will be enthusiastically adopted by local health workers and interested parties. Moreover, the knowledge was diffused from the primary population of village doctors, family planning workers, women's cadres, and teachers to the secondary population of villagers and students. [ABSTRACT FROM AUTHOR]

This paper proposes a new intensity-based similarity metric that can be used for the registration of multimodal images. It combines the robust estimation with both the forward and inverse transformation to reduce the negative effects of outliers in the images. For this purpose, we firstly employ the multiresolution technique to downsample the original images, then resort to the simulated annealing method to initialize the transformation parameters at the coarsest resolution. Finally the Powell method is utilized to obtain the optimal transformation parameters at each resolution. In our experiments, the new method is compared to other popular similarity measures, on the synthetic data as well as the real data, and the experimental results are encouraging. [ABSTRACT FROM AUTHOR]

In this paper, a nonrigid registration method is presented for accommodating local shape variation when matching monomodal images or multimodal images. Affine transformation is adopted in global registration while local deformation is described by a free-form deformation based on a linear singular blending (LSB) B-spline, which can enhance the shape-control capability of the B-spline. This capability is derived from the blending parameters defined at the B-spline control points. The local deformation of images can be controlled by changing positions of the control points or altering values of blending parameters. Two voxel-based similarity measures, the SSD for monomodal images and mutual information for multimodal images are used. Experiments on simulated and real data have been performed to evaluate the accuracy of our method. We have also compared the results of the proposed approach to those obtained by affine and B-spline registration techniques. The results indicate that the proposed method is much better to describe the deformation than the affine algorithm and B-spline techniques. [Copyright &y& Elsevier]

The article explores tobacco control in China as of 2018, focusing on whether or not tobacco crop substitution could aid the cause. Additional topics discussed include how China sets a quota for tobacco leaf production to ensure revenue to the state, the health impact of China's transition to a developed country and world economic power, and social conditions for farmers in China. The WHO (World Health Organization) and the United Nations Development Program are also noted.

Introduction: Low oxygen saturation suggests severe heart or respiratory disease. Most practitioners consider less than 95% as abnormal oxygen saturation in infants. Experts have recommended this cut-off value based on large-sample studies at or near sea level. However, there are few large-sample studies of infants born at low to moderate altitudes. The aim of this study is to determine threshold values of newborn oxygen saturation at low to moderate altitudes. Methods: We included 35 hospitals located in the Yunnan province of China, with altitudes varying from 267 to 2,202 meters. The hospitals recruited 41,097 consecutively born, asymptomatic neonates between Aug. 2015 and Jun. 2016. Obstetric nurses measured pre- and post-ductal oxygen saturation of each baby at 24 hours of age and before hospital discharge. Results: We categorized all births, according to the altitude of birth, into three groups: low altitude (0 to 500 meters), low to moderate altitude (500 to 1,500 meters), and moderate altitude (1,500 to 2,500 meters). The mean of pre-ductal oxygen saturation measured at 24 hours of age was 97.9% at low attitudes, 96.4% at low to moderate altitudes and 95.5% at moderate attitudes. We considered the 2.5th percentile as the cut off threshold, and recommended cut-off values of 95% for low altitudes, 93% for low to moderate altitudes, and 92% for moderate altitudes. Conclusion: These findings provide revised threshold values of oxygen saturation for pediatricians and obstetricians when screening newborns for severe congenital heart and lung disease at low to moderate altitudes. [ABSTRACT FROM AUTHOR]

Ultrasound poroelastography aims at assessing the poroelastic behavior of biological tissues via estimation of the local temporal axial strains and effective Poisson’s ratios (EPR). Currently, reliable estimation of EPR using ultrasound is a challenging task due to the limited quality of lateral strain estimation. In this paper, we propose a new two-step EPR estimation technique based on dynamic programming elastography (DPE) and Horn-Schunck (HS) optical flow estimation. In the proposed method, DPE is used to estimate the integer axial and lateral displacements while HS is used to obtain subsample axial and lateral displacements from the motion-compensated pre-compressed and post-compressed radio frequency data. Axial and lateral strains are then calculated using Kalman filter-based least square estimation. The proposed two-step technique was tested using finite-element simulations, controlled experiments and in vivo experiments, and its performance was statistically compared with that of analytic minimization (AM) and correlation-based method (CM). Our results indicate that our technique provides EPR elastograms of higher quality and accuracy than those produced by AM and CM. Regarding signal-to-noise ratio and elastographic contrast-to-noise ratio, in simulated data, the proposed method provides an average improvement of 30% and 75%, respectively, with respect to AM and of 100% and 169%, respectively, with respect to CM, whereas, in experiments, the proposed approach provides an average improvement of 30% and 67% with respect to AM and of 230% and 525% with respect to CM. Based on these results, the proposed method may be the preferred one in experimental poroelastography applications. [ABSTRACT FROM PUBLISHER]

ABSTRACT Biological images with significant intensity inhomogeneity are considerably difficult for the tissue segmentation. To overcome the difficulties caused by the intensity inhomogeneity, this study presents a variational level set method to simultaneous bias field estimation and tissue segmentation for images in the presence of intensity inhomogeneity. An energy function is defined in terms of two data fitting terms which incorporate the local clustering properties into the global region information. First, depended on the observed image mode, the local cluster property based on the observed signal is simplified to a criterion function which is similar to the Mumford-Shah model. The local criterion energy is then integrated with a global region measure, which is based on intensity difference of the true signal. The energy is minimized in a variational level set formulation with a regularity term, thus avoiding the expensive computation of the level set reinitialization and keeping the curve close to the signal distance function. Experiment results on biological images show desirable performance and demonstrate the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Abstract: In the study of early brain development, tissue segmentation of neonatal brain MR images remains challenging because of the insufficient image quality due to the properties of developing tissues. Among various brain tissue segmentation algorithms, atlas-based brain image segmentation can potentially achieve good segmentation results on neonatal brain images. However, their performances rely on both the quality of the atlas and the spatial correspondence between the atlas and the to-be-segmented image. Moreover, it is difficult to build a population atlas for neonates due to the requirement of a large set of tissue-segmented neonatal brain images. To combat these obstacles, we present a longitudinal neonatal brain image segmentation framework by taking advantage of the longitudinal data acquired at late time-point to build a subject-specific tissue probabilistic atlas. Specifically, tissue segmentation of the neonatal brain is formulated as two iterative steps of bias correction and probabilistic-atlas-based tissue segmentation, along with the longitudinal atlas reconstructed by the late time image of the same subject. The proposed method has been evaluated qualitatively through visual inspection and quantitatively by comparing with manual delineations and two population-atlas-based segmentation methods. Experimental results show that the utilization of a subject-specific probabilistic atlas can substantially improve tissue segmentation of neonatal brain images. [Copyright &y& Elsevier]

Background: Complications of ventral hernia repair (VHR) may be investigated by computed tomography or ultrasound (US) but neither modality gives a quantifiable metric of repair quality short of identifying hernia recurrence. Platelet-rich plasma (PRP), a growth factor-rich autologous blood product, has been shown to improve incorporation of native tissue with bioprosthetics. In this study, we investigate the effect of PRP on the incorporation and mechanical integrity of a non-crosslinked porcine acellular dermal matrix (pADM) in a rodent model of VHR and the correlative ability of ultrasound shear wave elastography (US-SWE) to assess repair quality.Methods: PRP was isolated from whole blood of Lewis rats. Twenty-eight Lewis rats underwent chronic VHR using either pADM alone or augmented with autologous PRP prior to non-invasive imaging assessment and specimen harvest at either 3 or 6 months. US-SWE was performed to estimate the Young's modulus prior to histological assessment and data from PRP-treated rodents were compared to controls.Results: Implanted pADM was easily distinguishable by US-SWE imaging in all cases analyzed in this study. The mean Young's modulus measured was 1.78 times and 2.54 times higher in PRP-treated samples versus control at 3-month and 6-month time points respectively (p < 0.05). At 3 months, qualitative and quantitative histology revealed decreased inflammation and improved incorporation in PRP-treated samples along the implant/abdominal wall interface. At 6 months, the PRP cohort had no hernia recurrence and preserved ADM integrity from immunologic degradation, while all control animals suffered hernia recurrence (4/6) or extreme ADM thinning (2/6).Conclusion: This study confirms both the efficacy of PRP in augmenting VHR using pADM, as well as the reliability of US-SWE to non-invasively predict the quality of VHR. Although further human studies are necessary, this work supports PRP use to improve VHR outcomes and US-SWE potential for bedside non-invasive hernia characterization. [ABSTRACT FROM AUTHOR]

Background: Crowdsourcing, the process of shifting individual tasks to a large group, may be useful for health communication, making it more people-centered. We aimed to evaluate whether a crowdsourced video is non-inferior to a social marketing video in promoting condom use.Methods: Men who have sex with men (MSM) (≥16 years old, had condomless sex within three months) were recruited and randomly assigned to watch one of the two videos in 2015. The crowdsourced video was developed through an open contest and the social marketing video was designed by using social marketing principles. Participants completed a baseline survey and follow-up surveys at three weeks and three months post-intervention. The outcome was compared with a non-inferiority margin of +10%.Results: Among the 1173 participants, 907 (77%) and 791 (67%) completed the three-week and three-month follow-ups. At three weeks, condomless sex was reported by 146/434 (33.6%) and 153/473 (32.3%) participants in the crowdsourced and social marketing arms, respectively. The crowdsourced intervention achieved non-inferiority (estimated difference: +1.3%, 95%CI: -4.8 to 7.4%). At three months, 196/376 (52.1%) and 206/415 (49.6%) individuals reported condomless sex in the crowdsourced and social-marketing arms (estimated difference: +2.5%, 95%CI: -4.5 to 9.5%). The two arms also had similar HIV testing rates and other condom-related secondary outcomes.Our study demonstrates that crowdsourced message is non-inferior to a social marketing intervention in promoting condom use among Chinese MSM. Crowdsourcing contests could have a wider reach than other approaches and create more people-centered intervention tools for HIV control. [ABSTRACT FROM AUTHOR]

Aims: To examine drug use behavior of clients attending Methadone Maintenance Treatment (MMT) programs and its relationship with the clients’ social network characteristics. Design: Cross-sectional study. Setting: Four MMT clinics in Kunming, Yunnan province, China. Participants: 324 consecutive MMT clients. Measurements: A structured, self-completed questionnaire on background characteristics and existing social network. Current drug use was assessed by urine test for opiate metabolites. Analysis: The association between client's social network characteristics and their own current drug use behavior is analysed using multiple logistic regression adjusting for socio-demographic characteristics. Adjusted odds ratios (AOR) with 95% confidence intervals (CI) are obtained to give the strength of the associations. Findings: MMT clients were more likely to concurrently use heroin while attending MMT if their social network had any of the following characteristics: more than half of the members were older than them (AOR = 1.03, 95% CI = 1.00,1.06), any member had a high level of influence on them (AOR = 6.47, 95% CI = 2.86,14.65) and any member joined them in using drugs (AOR = 1.94, 95% CI = 1.04,3.63). Having a social network member who could provide emotional support (AOR = 0.11, 95% CI = 0.03,0.35), having a spouse and/or child in their social network (AOR = 0.44, 95% CI = 0.24,0.81) and having a social network member with a high level of closeness (AOR = 0.28, 95% CI = 0.09,0.90) were associated with a decreased odds of heroin use. Conclusion: Social networks who could provide MMT clients with emotional support and a close relationship were significant factors for reducing the risk of concurrent drug use among clients attending MMT clinics in Kunming, China. Behavioral interventions should address the role of family and social network members in providing support to these clients. [ABSTRACT FROM AUTHOR]

Background: Despite the reduction in reported incidence of tuberculosis globally, the burden of pulmonary tuberculosis (PTB) remains high in low- and middle- income countries, including China. The current study aims to evaluate the distribution and trend of PTB incidence in Xinjiang, the region with the highest PTB burden in China. Methods: We identified all confirmed PTB case records reported to the Chinese TB Information Management System (TBIMS) between 2011 and 2015. We analyzed these records to measure the annual incidence of reported smear-positive PTB cases in Xinjiang and its trend over time. We also analyzed incidence by gender, residential area, and region. Spatial analysis was used to describe the inter-regional disparity of the disease burden during the study period. Results: We identified 212,216 smear-positive PTB cases between 2011 and 2015. The reported incidence increased from 180.8 cases in 2011 to 195.8 cases in 2015 per 100,000 population. The southern region of Xinjiang had the highest disease burden (257.8/100,000 in 2011 and 312.7/100,000 in 2015). More than 60% cases occurred in persons >45 years, and 76% of cases lived in rural areas. Conclusion: To reach the goal of elimination and control of TB, more comprehensive STOP TB strategies should be implemented in Xinjiang. Residents in the southern region and rural areas of Xinjiang require particular attention. [ABSTRACT FROM AUTHOR]

This paper proposes an infrared target detection algorithm based on lateral inhibition (LI) and singular value decomposition (SVD). Firstly, a local structure descriptor based on SVD of gradient domain is constructed, which reflects basic structures of the local regions of an infrared image. Then, LI network is modified by combining LI with the local structure descriptor for enhancing target and suppressing background. Meanwhile, to calculate lateral inhibition coefficients adaptively, the direction parameters are determined by the dominant orientations obtained from SVD. Experimental results show that, compared with the typical algorithms, the proposed algorithm not only can detect small target or area target under complex backgrounds, but also has excellent abilities of background suppression and target enhancement. [ABSTRACT FROM AUTHOR]

Background: Among Kazakh-Chinese population in Xinjiang province of China, prevalence of obesity and hypertension were 40.1% and 50.3% respectively, the highest across all ethnic groups residing in this pastureland. Despite this, there remained a dearth of information regarding the association between the anthropometric measures [body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR), Waist-to-height ratio (WHtR) etc.] and indicators for hypertension control [achieved levels of systolic and diastolic blood pressures (SBP and DBP), pulse pressure index (PPI), ankle-brachial index (ABI) etc.] among them. Method: A cross-sectional study was conducted in Xinjiang to determine the distribution and inter-relationships of the anthropometric measures and indicators for achieved BP control as well as their predictors among hypertension patients of Kazakh-Chinese ethnicity. Out of 550 randomly selected patients, 516 completed the interview, anthropometry and BP assessments. Results: In the sample population, average SBP, DBP and PP were 156.26±24.40mmHg, 87.55±14.73mmHg and 68.71±19.39mmHg respectively. Bivariate analysis identified age, gender, education, duration of hypertension, WC and BMI being factors influencing the achieved levels of BP. Adjusted multiple linear regression models elicited positive associations of age (βa = 0.152, p = 0.001) and duration of hypertension (βa = 0.132, p = 0.003) with achieved level of SBP as well as BMI (βa = 0.135, p = 0.002) with DBP. Age (βa = 0.207, p<0.001) and WHtR (βa = 0.304, p = 0.005) were positively and WC (βa = -0.406, p<0.001) was negatively associated with PPI. Increasing age (βa = -0.125, p = 0.005), female gender (βa = -0.122, p = 0.005) and 5years’ duration of hypertension (βa = -0.091, p<0.039) were negatively associated with ABI. After adjustment for socio-demographic variables, hypertensive patients with (reference = without) abdominal obesity had 93% (p = 0.013) higher odds of missing the target BP control. Conclusion: Anthropometric measures and indicators for blood pressure control among Kazakh-Chinese patients were far beyond normal. Several anthropometric measures appeared useful for monitoring BP. Using them, regular screening and consequent targeted intervention were required urgently to control hypertension among Kazakh-Chinese. [ABSTRACT FROM AUTHOR]

Background: Innovation contests call on non-experts to help solve problems. While these contests have been used extensively in the private sector to increase engagement between organizations and clients, there is little data on the role of innovation contests to promote health campaigns. We implemented an innovation contest in China to increase sexual health awareness among youth and evaluated community engagement in the contest.Methods: The sexual health image contest consisted of an open call for sexual health images, contest promotion activities, judging of entries, and celebrating contributions. Contest promotion activities included in-person and social media feedback, classroom didactics, and community-driven activities. We conducted 19 semi-structured interviews with a purposive sample to ensure a range of participant scores, experts and non-expert participants, submitters and non-submitters. Transcripts of each interview were coded with Atlas.ti and evaluated by three reviewers.Results: We identified stages of community engagement in the contest which contributed to public health impact. Community engagement progressed across a continuum from passive, moderate, active, and finally strong engagement. Engagement was a dynamic process that appeared to have little relationship with formally submitting an image to the contest. Among non-expert participants, contest engagement increased knowledge, healthy attitudes, and empowered participants to share ideas about safe sex with others outside of the contest. Among experts who helped organize the contest, the process of implementing the contest fostered multi-sectoral collaboration and re-oriented public health leadership towards more patient-centered public health campaigns.Conclusion: The results of this study suggest that innovation contests may be a useful tool for public health promotion by enhancing community engagement and re-orienting health campaigns to make them more patient-centered. [ABSTRACT FROM AUTHOR]

Introduction: HIV and syphilis testing rates remain low among men who have sex with men (MSM) in low- and middle-income countries (LMICs). Community engagement has been increasingly used to promote HIV testing among key populations in high-income countries, often in settings with stronger civil society. This study aimed to assess socio-demographic, behavioural, and community engagement factors associated with HIV and syphilis testing among MSM in China. Methods: MSM ≥16 years old who had condomless sex in the past three months were recruited nationwide to complete a cross-sectional online survey in November 2015. Data were collected on socio-demographics, sexual behaviours, HIV testing, syphilis testing, and community engagement in sexual health. We defined community engagement in sexual health using six items assessing awareness and advocacy of sexual health programmes. The underlying factor structure of a 6-item community engagement scale was determined through exploratory factor analysis. Univariate and multivariable logistic regressions identified correlates of HIV and syphilis testing. Results: 1189 MSM were recruited. 54% (647/1189) of men had ever tested for HIV and 30% (354/1189) had ever tested for syphilis. Factor analysis suggested three levels of community engagement (minimal, moderate, and substantial) and this model explained 79.5% of observed variance. A quarter (26%, 312/1189) reported none to minimal engagement, over one half (54%, 644/1189) reported moderate engagement, and a fifth (20%, 233/1189) reported substantial engagement. Multivariable logistic regression showed that MSM with greater community engagement in sexual health were more likely to have ever tested for HIV (substantial vs. no engagement: aOR 7.91, 95% CI 4.98–12.57) and for syphilis (substantial vs. no engagement: aOR 5.35, 95% CI 3.16–9.04). Conclusions: HIV and syphilis testing are suboptimal among MSM in China. Community engagement may be useful for promoting testing in China and should be considered in intervention development and delivery. Further research is needed to better understand the role of LMIC community engagement in HIV interventions. [ABSTRACT FROM AUTHOR]

Medical ultrasound images are corrupted by speckle noise, which is multiplicative. This noise limits the contrast resolution in these images and complicates image-based quantitative measurement and diagnosis. In this study, the speckle noise in the ultrasound image is modeled by local statistics of the intensity distribution. And the non-local mean (NLM) filter is utilized to filter additional noise by applying the redundancy information in noisy images. A hybrid denoising method is proposed in consideration of the characteristics of both the local statistics of speckle noise and the NLM filter. The study combines local statistics with the NLM filter to reduce speckle in ultrasound images. The local statistics of speckle noise is estimated by local patches, while the intensity of the denoising pixel is computed by the weighted average of all the pixels by using the NLM. The weight is determined according to the similarity measures between the intensities of the local patches. The performance of the proposed method is evaluated on synthetic data, simulated images, and real images. Results of quantitative analysis and visual inspection of the synthetic data and of the real images demonstrate that the proposed method outperforms the original NLM, as well as many previously developed methods. [ABSTRACT FROM AUTHOR]

Background: Considering the importance of health literacy (HL) for the maximum yield from the hypertension control programs, development of a reliable and valid instrument of hypertension-related HL is critical. This study aimed to translate and validate the High Blood Pressure-Health Literacy Scale (HBP-HLS) into Chinese (C-HBP-HLS) and evaluate its psychometric properties in Chinese context. Method: Between June 2013 and January 2014, a cross-sectional study was conducted among recruited hypertensive patients belonging to the Han and Kazakh-Chinese communities in Urumqi, Xinjiang, China. Results: A pilot sample (n = 242) was selected for the exploratory factor analysis of the translated and modified instrument. Another sample (n = 308) was recruited for the confirmatory factor analysis. C-HBP-HLS consisted of five dimensions (Print Health Literacy, Medication Label, Understanding Ability, Newest Vital Sign Test, and Avoiding Food Allergy) containing 15 items, accounting for 77.7% of the total variance. The 5-factor model demonstrated a good overall fit. The scale-level content validity index was 0.85. Cronbach’s alpha of the overall scale was 0.78 and test-retest reliability was 0.96. Education level had a strong positive correlation with the scores for items Q1, Q2, and Q3(r = 0.481, 0.492, 0.475, respectively). Health Literacy scores among Kazakh patients were significantly lower than Han (7.13±7.90 vs. 30.10±13.42, Z = -14.573, P<0.001). Conclusion: C-HBP-HLS demonstrated suitable factor structure and robust psychometric properties for measuring health literacy level among hypertensive patients in China. [ABSTRACT FROM AUTHOR]

This study proposes a novel adaptive mesh expansion model (AMEM) for liver segmentation from computed tomography images. The virtual deformable simplex model (DSM) is introduced to represent the mesh, in which the motion of each vertex can be easily manipulated. The balloon, edge, and gradient forces are combined with the binary image to construct the external force of the deformable model, which can rapidly drive the DSM to approach the target liver boundaries. Moreover, tangential and normal forces are combined with the gradient image to control the internal force, such that the DSM degree of smoothness can be precisely controlled. The triangular facet of the DSM is adaptively decomposed into smaller triangular components, which can significantly improve the segmentation accuracy of the irregularly sharp corners of the liver. The proposed method is evaluated on the basis of different criteria applied to 10 clinical data sets. Experiments demonstrate that the proposed AMEM algorithm is effective and robust and thus outperforms six other up-to-date algorithms. Moreover, AMEM can achieve a mean overlap error of 6.8% and a mean volume difference of 2.7%, whereas the average symmetric surface distance and the root mean square symmetric surface distance can reach 1.3 mm and 2.7 mm, respectively. [ABSTRACT FROM AUTHOR]

In China, approximately 20 million farmers produce the world's largest share of tobacco. Showing that income from crop substitution can exceed that from tobacco growth is essential to persuading farm families to stop planting tobacco, grown abundantly in Yunnan Province. In the Yuxi Municipality, collaborators from the Yuxi Bureau of Agriculture and the University of California at Los Angeles School of Public Health initiated a tobacco crop substitution project. At 3 sites, 458 farm families volunteered to participate in a new, for-profit cooperative model. This project successfully identified an approach engaging farmers in cooperatives to substitute food crops for tobacco, thereby increasing farmers' annual income between 21% and 110% per acre. (Am J Public Health. 2012;102:1660-1663.) [ABSTRACT FROM AUTHOR]

In China, one of the major problems in upgrading rural health services is the difficulty of communicating between the rural and urban areas. Enabling local agencies to access the Internet in resource-poor areas can provide an efficient means of diffusing current training and information and will have far-reaching policy implications. To test the feasibility of using the Internet to deliver needed health information to the countryside, the UCLA School of Public Health and the Institute of Health Studies of Kunming Medical College (IHS-KMC) collaborated in an experimental website project to improve the quality of reproductive health services to promote women's health in three rural counties of Yunnan. The project involved the county government and the Bureau of Public Health, the Bureau of Family Planning; the Bureau of Education, Women's Federation, and the Maternal and Child Health Station targeting village health workers and teachers; women's cadres. Three counties, matched on socioeconomic status, participated in the study and were randomized to receive three programs. Nanhua County received computer skill training and logistic support including a planning workshop for information diffusion. Mouding County received computers only. Dayao, the control county, did not receive the full program until the conclusion of the project. The study demonstrated that the use of a website to disseminate health information in remote rural areas is not only feasible but that it also will be enthusiastically adopted by local health workers and interested parties. Moreover, the knowledge was diffused from the primary population of village doctors, family planning workers, women's cadres, and teachers to the secondary population of villagers and students. [ABSTRACT FROM AUTHOR]

Three-dimensional reconstruction of vessels from digital X-ray angiographic images is a powerful technique that compensates for limitations in angiography. It can provide physicians with the ability to accurately inspect the complex arterial network and to quantitatively assess disease induced vascular alterations in three dimensions. In this paper, both the projection principle of single view angiography and mathematical modeling of two view angiographies are studied in detail. The movement of the table, which commonly occurs during clinical practice, complicates the reconstruction process. On the basis of the pinhole camera model] and existing optimization methods, an algorithm is developed for 3-D reconstruction of coronary arteries from two uncalibrated monoplane angiographic images. A simple and effective perspective projection model is proposed for the 3-D reconstruction of coronary arteries. A nonlinear optimization method is employed for refinement of the 3-D structure of the vessel skeletons, which takes the influence of table movement into consideration. An accurate model is suggested for the calculation of contour points of the vascular surface, which fully utilizes the information in the two projections. In our experiments with phantom and patient angiograms, the vessel centerlines are reconstructed in 3-D space with a mean positional accuracy of 0.665 mm and with a mean back projection error of 0.259 mm. This shows that the algorithm put forward in this paper is very effective and robust. [ABSTRACT FROM AUTHOR]

We report community-based development of reproductive health indicators for China''s rural areas. To generate these indicators, we sequenced two participatory techniques known as nominal group process and Delphi survey methodology. Nominal group process entailed grassroots reproductive health workers’ generating indicators, followed by refinement and prioritization of these indicators through a consensus-building Delphi process among nationally and internationally known reproductive health experts. Major criteria for the indicators were practicality, feasibility, and measurability within China''s rural areas. We explain the importance of establishing these indicators for application in rural China and other developing countries as a complement to the World Health Organization''s reproductive health indicators for global monitoring; present the identified indicators; and describe lessons learned from field testing in low-, middle-, and high-income counties of China''s countryside. [Copyright &y& Elsevier]

Background: Sex tourism among men who have sex with men (MSM) may exacerbate transmission of HIV and other sexually transmitted infections (STIs). Sex tourism is defined as purchasing sex with gifts or money outside of one's hometown. Our objective was to characterize the frequency, socio-demographic characteristics, and sexual risk behaviors among Chinese MSM sex tourists.Methods: An online, cross-sectional survey for high-risk MSM throughout China was conducted in November 2015 covering sociodemographic characteristics, sexual risk behaviors, and sex tourism. Univariate and multivariable logistic regressions were performed to identify correlates of sex tourism. The mean MSM HIV prevalence of sex tourism journey origins and destinations were compared.Results: Of 1189 MSM who completed the survey, 62 (5%) men identified as sex tourists; among these sex tourists, twenty (32%) traveled primarily to purchase sex and the remainder purchased sex while traveling for another purpose. There was minimal socio-demographic and behavioral difference between the two groups. In multivariable analyses, adjusting for age and income, sex tourism was correlated with high-risk sexual behaviors, higher income (aOR 4.44, 95%CI 1.77-11.18) and living with HIV (aOR 2.79, 95%CI 1.03-7.55). Sex tourism was more often from locations with lower to higher MSM HIV prevalence (mean = 4.47, SD = 2.01 versus mean = 6.86, SD = 5.24).Conclusion: MSM sex tourists were more likely to have risky sexual behaviors and travel to locations with a higher HIV prevalence. MSM sex tourists may be part of core groups that are disproportionately responsible for MSM HIV transmission. Enhanced surveillance and interventions tailored to MSM sex tourists should be considered. [ABSTRACT FROM AUTHOR]