Household air pollution and childhood stunting in China: A prospective cohort study.

Background: Exposure to air pollution, especially indoor air pollution, was associated with an increased risk of childhood stunting. However, few longitudinal studies have explored the long-term impacts of indoor air pollution from household solid fuel use on child growth. We aimed to investigate the association between household air pollution (HAP) from solid fuel use and childhood stunting in Chinese children. Method: The longitudinal data from the Chinese Family Panel Study over 2010-2018 were included in this study with a total of 6,013 children aged 0-15 years enrolled at baseline. Exposure to HAP was measured as solid fuel use for cooking, while solid fuel was defined as coal and firewood/straw according to the questionnaire survey. Stunting was defined as-2SD below the height-for-age z-score (HAZ) of the reference children. Logistic regression and Cox proportional hazards models with time-varying exposures were employed to estimate the association between childhood stunting and HAP exposure. Results: At baseline, children with exposure to HAP from combusting solid fuels had a relatively higher risk of stunting [OR (95%CI): 1.42 (1.24-1.63)]. Among children without stunning at baseline, those living in households with solid fuel use had a higher stunting risk over an 8-year follow-up [HR (95%CI): 2.05 (1.64-2.57)]. The risk of childhood stunting was increased for those with HAP exposure from firewood/straw combustion or with longer exposure duration [HR (95%CI): 2.21 (1.74-2.79) and 3.01 (2.23-4.08), respectively]. Meanwhile, this risk was significantly decreased among children from households switching from solid fuels to clean fuels [HR (95%CI): 0.53 (0.39-0.70)]. Solid fuel use was suggested to be a mediator of the relationship between poor socioeconomic factors (i.e., household income and parental education level) and childhood stunning, with a mediation effect ranging from 11.25 to 14.26%. Conclusions: HAP exposure from solid fuel use was associated with childhood stunting. Poor parental education and low household income might be socioeconomic factors contributing to solid fuel use. Therefore, household energy policies to facilitate access to clean fuels are urgently needed, especially for low-income and low-educated households.

Identifying the natural and anthropogenic factors influencing the spatial disparity of population hollowing in traditional villages within a prefecture-level city.

In developing countries, the phenomena of rural depopulation have been an intense continuing, which have become a major bottleneck for the sustainable revitalization of traditional villages. However, the factors influencing the spatial disparity of population hollowing (SDPH) in traditional villages within a prefecture-level city have not been fully quantitatively researched. Based on the factors that influence general villages, this study incorporated historical and cultural factors related to traditional village characteristics to construct a targeted influencing factor index system and then identified the key factors by applying the geo-detector method. With the percentage of resident population (PRP) used as a metric, this study examined Lishui, one of China's traditional village agglomeration regions, as an example to explore SDPH in traditional villages. The results of this study were revealed in the following. (1) The average PRP value in traditional villages in Lishui was 0.68, with clear spatial disparities between the northern region (0.73) and the southern region (0.57). (2) The factors driving the SDPH included both natural and anthropogenic factors; of these, altitude, the number of public facilities, and the number of communication base stations were the most significant influencing factors. In contrast, historical and cultural factors have relatively low impacts. (3) The interaction relationships of pair factors were often enhanced on a bivariate basis, with the highest enhanced impact occurring from the interaction of two variables: the degree of intangible cultural inheritance and altitude. (4) The intervals of the variables leading to the hollowing of the population above a moderate level can be detected. This method can effectively analyze the factors influencing SDPH in traditional villages; can help reveal the interaction impact of pair factors; and can help identify the factors' risk intervals.

Continuity of Care Is Associated with Medical Costs and Inpatient Days in Children with Cerebral Palsy.

Background: Children with cerebral palsy (CP) place a considerable burden on medical costs and add to an increased number of inpatient days in Taiwan. Continuity of care (COC) has not been investigated in this population thus far. Materials and Methods: We designed a retrospective population-based cohort study using Taiwan's National Health Insurance Research Database. Patients aged 0 to 18 years with CP catastrophic illness certificates were enrolled. We investigated the association of COC index (COCI) with medical costs and inpatient days. We also investigated the possible clinical characteristics affecting the outcome. Results: Over five years, children with CP with low COCI levels had higher medical costs and more inpatient days than did those with high COCI levels. Younger age at CP diagnosis, more inpatient visits one year before obtaining a catastrophic illness certificate, pneumonia, and nasogastric tube use increased medical expenses and length of hospital stay. Conclusions: Improving COC reduces medical costs and the number of inpatient days in children with CP. Certain characteristics also influence these outcomes.

Real-World Cost-Effectiveness Analysis of Gemcitabine and Cisplatin Compared to Docetaxel and Cisplatin Plus Fluorouracil Induction Chemotherapy in Locoregionally Advanced Nasopharyngeal Carcinoma.

BACKGROUND: Addition of gemcitabine and cisplatin (GP) or docetaxel and cisplatin plus fluorouracil (TPF) to concurrent chemoradiotherapy (CCRT) significantly improved survival in locoregionally advanced nasopharyngeal carcinoma (NPC). However, an economic evaluation of these regimens remains unknown. The purpose of this study is to compare the cost-effectiveness of GP versus TPF regimen in the treatment of locoregionally advanced NPC in China. MATERIALS AND METHODS: A comprehensive Markov model was developed to evaluate the health and economic outcomes of GP versus TPF regimen for patients with locoregionally advanced NPC. Baseline and clinical outcome were derived from 158 patients with newly diagnosed stage III-IVA NPC between 2010 and 2015. We evaluated the quality-adjusted life-years (QALYs), costs, and incremental cost-effectiveness ratios (ICERs) from the perspective of the Chinese healthcare system. One-way sensitive analysis explored the impact of uncertainty in key model parameters on results, and probabilistic uncertainty was assessed through a Monte Carlo probabilistic sensitivity analysis. RESULTS: GP regimen provided an additional 0.42 QALYs with incremental cost of $3,821.99, resulting in an ICER of $9,099.98 per QALY versus TPF regimen at the real-world setting. One-way sensitivity analysis found that the results were most sensitive to the cost and proportion of receiving subsequent treatment in two groups. The probability that GP regimen being cost-effective compared with TPF regimen was 86.9% at a willingness-to-pay (WTP) of $31,008.16 per QALY. CONCLUSION: Using real-world data, GP regimen was demonstrated a cost-effective alternative to TFP regimen for patients with locoregionally advanced NPC in China. It provides valuable evidence for clinicians when making treatment decisions to improve the cost-effectiveness of treatment.

An Integrated Framework Based on Full Monte Carlo Simulations for Double-Scattering Proton Therapy.

PURPOSE: We developed an integrated framework that employs a full Monte Carlo (MC) model for treatment-plan simulations of a passive double-scattering proton system. MATERIALS AND METHODS: We have previously validated a virtual machine source model for full MC proton-dose calculations by comparing the percentage of depth-dose curves, spread-out Bragg peaks, and lateral profiles against measured commissioning data. This study further expanded our previous work by developing an integrate framework that facilitates its clinical use. Specifically, we have (1) constructed patient-specific applicator and compensator numerically from the plan data and incorporated them into the beamline, (2) created the patient anatomy from the computed tomography image and established the transformation between patient and machine coordinate systems, and (3) developed a graphical user interface to ease the whole process from importing the treatment plan in the Digital Imaging and Communications in Medicine format to parallelization of the MC calculations. End-to-end tests were performed to validate the functionality, and 3 clinical cases were used to demonstrate clinical utility of the framework. RESULTS: The end-to-end tests demonstrated that the framework functioned correctly for all tested functionality. Comparisons between the treatment planning system calculations and MC results in 3 clinical cases revealed large dose difference up to 17%, especially in the beam penumbra and near the end of beam range. The discrepancy likely originates from a variety of sources, such as the dose algorithms, modeling of the beamline, and the dose metric. The agreement for other regions was acceptable. CONCLUSION: An integrated framework was developed for full MC simulations of double-scattering proton therapy. It can be a valuable tool for dose verification and plan evaluation.

A Multiview Learning Framework With a Linear Computational Cost.

Learning features from multiple views has attracted much research attention in different machine learning tasks, such as multiclass and multilabel classification problems. In this paper, we propose a multiclass multilabel multiview learning framework with a linear computational cost where an example is associated with at least one label and represented by multiple information sources. We simultaneously analyze all features by learning an integrated projection matrix. We can also automatically select more important views for subsequent classifier to predict each class. As the proposed objective function is nonsmooth and difficult to solve, we apply a novel optimization method that converts the multiview learning problem to a set of linear single-view learning problems by bridging our problem to an easily solvable approach. Compared to the conventional methods which learn the entire projection matrix, our algorithm independently optimizes each column of the projection matrix for each class, which can be easily parallelized. In each column optimization, the most computationally intensive step is pure and simple matrix-by-vector multiplication. As a result, our algorithm is much more applicable to large-scale problems than the multiview learning methods with a nonlinear computational cost. Moreover, rigorous convergence proof of the proposed algorithm is also provided. To evaluate the effectiveness of the proposed approach, experimental comparisons are made with state-of-the-art algorithms in multiclass and multilabel classification tasks on many multiview benchmarks. We also report the efficiency comparison results on different numbers of data samples. The experimental results demonstrate that our algorithm can achieve superior performance to all the compared algorithms.

Is manipulative therapy clinically necessary for relief of neck pain? A systematic review and meta-analysis.

OBJECTIVE: To summarize and critically assess the effificacy of Eastern and Western manipulative therapies for the treatment of neck pain in adults. METHODS: A search of PubMed/MEDLINE, the Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, EMBASE, etc. from their inception date to January 2014 with Chinese, Japanese, and Korean databases. Two reviewers independently selected randomized controlled trials (RCTs) with negative control or blank control, extracted data and assessed methodological quality. Meta-analysis and levels of evidence were performed by Revman5.1 and Grades of Recommendations Assessment, Development and Evaluation (GRADE) approach. RESULTS: Nineteen clinical trials with adequate randomization were included in this review, 11 of them had a low risk of bias. The primary outcome for short-term pain had no significant differences, however, the secondary outcome, only the Numerical Pain Rating Scale (NPRS) score of intermediate-term [n=916, pooled mean differences (MD) =-0.29, P=0.02], the Neck Disability Index (NDI) score of short-term (n=1,145, pooled MD=-2.10, P<0.01), and intermediate-term (n=987, pooled MD=-1.45, P=0.01) were signifificantly reduced with moderate quality evidence. However, it supported the minimally clinically important difference (MCID) of the Visual Analogue Scale and NPRS pain score to be 13 mm, while NDI was 3.5 points. The meta-analysis only suggested a trend in favor of manipulative therapy rather than clinical signifificance. CONCLUSIONS: The results do not support the existing evidences for the clinical value of Eastern or Western manipulative therapy for neck pain of short-term follow-up according to MCIDs. The limitations of our review related to blinding, allocation concealment and small sample size.

Experimental Validation of Monte Carlo Simulations Based on a Virtual Source Model for TomoTherapy in a RANDO Phantom.

A virtual source model for Monte Carlo simulations of helical TomoTherapy has been developed previously by the authors. The purpose of this work is to perform experiments in an anthropomorphic (RANDO) phantom with the same order of complexity as in clinical treatments to validate the virtual source model to be used for quality assurance secondary check on TomoTherapy patient planning dose. Helical TomoTherapy involves complex delivery pattern with irregular beam apertures and couch movement during irradiation. Monte Carlo simulation, as the most accurate dose algorithm, is desirable in radiation dosimetry. Current Monte Carlo simulations for helical TomoTherapy adopt the full Monte Carlo model, which includes detailed modeling of individual machine component, and thus, large phase space files are required at different scoring planes. As an alternative approach, we developed a virtual source model without using the large phase space files for the patient dose calculations previously. In this work, we apply the simulation system to recompute the patient doses, which were generated by the treatment planning system in an anthropomorphic phantom to mimic the real patient treatments. We performed thermoluminescence dosimeter point dose and film measurements to compare with Monte Carlo results. Thermoluminescence dosimeter measurements show that the relative difference in both Monte Carlo and treatment planning system is within 3%, with the largest difference less than 5% for both the test plans. The film measurements demonstrated 85.7% and 98.4% passing rate using the 3 mm/3% acceptance criterion for the head and neck and lung cases, respectively. Over 95% passing rate is achieved if 4 mm/4% criterion is applied. For the dose-volume histograms, very good agreement is obtained between the Monte Carlo and treatment planning system method for both cases. The experimental results demonstrate that the virtual source model Monte Carlo system can be a viable option for the accurate dose calculation of helical TomoTherapy.

Comparison of Ray Tracing and Monte Carlo Calculation Algorithms for Thoracic Spine Lesions Treated With CyberKnife-Based Stereotactic Body Radiation Therapy.

Stereotactic body radiation therapy (SBRT) is an emerging technology for the treatment of spinal metastases, although the dosimetric impact of the calculation method on spinal dose distribution is unknown. This study attempts to determine whether CyberKnife (CK)-based SBRT using a Ray Tracing (RyTc) algorithm is comparable dosimetrically to that of Monte Carlo (MC) for thoracic spinal lesions. Our institutional CK-based SBRT database for thoracic spinal lesions was queried and a cohort was generated. Patients were planned using RyTc and MC algorithms using the same beam angles and monitor units. Dose-volume histograms of the planning target volume (PTV), spinal cord, esophagus, and skin were generated, and dosimetric parameters were compared. There were 37 patients in the cohort. The average percentage volume of PTV covered by the prescribed dose with RyTc and MC algorithms was 91.1% and 80.4%, respectively (P < .001). The difference in average maximum spinal cord dose between RyTc and MC plans was significant (1126 vs 1084 cGy, P = .004), with the MC dose ranging from 18.7% below to 13.8% above the corresponding RyTc dose. A small reduction in maximum skin dose was also noted (P = .017), although no difference was seen in maximum esophageal dose (P = .15). Only PTVs smaller than 27 cm(3) were found to correlate with large (>10%) changes in dose to 90% of the volume (P = .014), while no correlates with the average percentage volume of PTV covered by the prescribed dose were demonstrated. For thoracic spinal CK-based SBRT, RyTc computation may overestimate the MC calculated average percentage volume of PTV covered by the prescribed dose and have unpredictable effects on doses to organs at risk, particularly the spinal cord. In this setting, use of RyTc optimization should be limited and always verified with MC.

Light-activated sealing of skin wounds.

BACKGROUND AND OBJECTIVES: We have developed a light-activated technology for rapidly sealing skin surgical wounds called photochemical tissue bonding (PTB). The goals of this study were to evaluate parameters influencing PTB in order to optimize its clinical efficacy and to determine whether PTB can be used to seal wounds in moderately to highly pigmented skin. STUDY DESIGN/MATERIALS AND METHODS: Application of Rose Bengal (RB) followed by exposure to 532 nm was used to seal linear incisions (1.5 mm deep, 2 cm long) in lightly pigmented (Yorkshire) and darkly pigmented (Yucatan) swine skin. The force required to open the seal (the bonding strength) was measured by in situ tensiometry. Reflectance spectra, epidermal transmission spectra, and histology were used to characterize the skin. The relationships of RB concentration and fluence to bonding strength were established in Yorkshire skin. Surface temperature was measured during irradiations and cooling was used while sealing incisions in Yucatan skin. Monte Carlo simulations were carried out to estimate the effect of epidermal melanin on the power absorbed in the dermis at the incision interface. RESULTS: The lowest fluence, 25 J/cm(2), delivered at an irradiance of 0.5 W/cm(2) substantially increased the bonding strength (∼ 10-fold) compared to controls in Yorkshire swine skin. Increasing the fluence to 100 J/cm(2) enhanced bonding strength by a further 1.5-fold. Application of 0.1% RB for 2 minutes produced the greatest bonding strength using 100 J/cm(2) and limited the penetration of RB to an ∼ 50 µm band on the dermal incision wall. Reflectance spectra indicated that Yorkshire skin had minimal melanin and that Yucatan skin was a good model for highly pigmented human skin. In Yucatan skin, the bonding strength increased 1.7-fold using 0.1% RB and 200 J/cm(2) at 1.5 W/cm(2) with cooling and epinephrine. Monte Carlo simulation indicated that absorption of 532 nm light by epidermal melanin in dark skin decreased the power absorbed along the incision in the dermis by a factor of 2.7. CONCLUSIONS: These results suggest that in lightly pigmented skin the PTB treatment time can be shortened without compromising the bonding strength. Sealing incisions using PTB in moderately and highly pigmented skin will require a careful balance of irradiance and cooling.

Phototoxicity is not associated with photochemical tissue bonding of skin.

BACKGROUND AND OBJECTIVE: We have developed a light-activated method called photochemical tissue bonding (PTB) for closing wounds using green light and a photosensitizing dye (Rose Bengal-RB) to initiate photochemical crosslinking of wound surface proteins. These studies were designed to determine whether RB causes phototoxicity during closure of skin incisions with PTB. STUDY DESIGN/MATERIALS AND METHODS: RB phototoxicity was evaluated after sealing incisions in porcine skin ex vivo and rabbit skin in vivo using PTB (1 mM RB, 100 J/cm(2), 532 nm, 0.3 or 0.5 W/cm(2).) Dead cells were identified by pyknotic nuclei and eosinophilic cytoplasm on H&E-stained sections. The influence on RB phototoxicity of penetration of RB into the wound wall (by confocal microscopy), RB concentration in the tissue (by extraction), and fluence of 532 nm reaching depths in skin (calculated from skin optical properties) were investigated. RESULTS: No significant differences were found in the percent dead cells in PTB-treated and control incisions in porcine skin at 24 hours or in rabbit skin at 2 hours and 3 and 7 days after surgery. RB was retained in a approximately 100 microm wide band next to the wound wall. The mean RB concentration within this band was 0.42+/-0.03 mM. Monte Carlo modeling of light distribution indicated that the fluence rate decreased from the subsurface peak to 0.5 W/cm(2) in the mid-dermis (approximately 350 microm.) In vitro RB phototoxicity to dermal fibroblasts yielded an LD(50) of 0.50+/-0.09 J/cm(2) when the cells contained 0.46 mM RB. CONCLUSIONS: PTB does not cause phototoxicity when used to repair skin wounds even though the RB concentration and 532 nm fluence in the mid-dermis during PTB are much greater than the LD(50) for RB phototoxicity in vitro. These results indicate that phototoxicity is not a concern when using PTB for tissue repair.

Value of FDG PET in assessment of treatment response and surveillance in head-and-neck cancer patients after intensity modulated radiation treatment: a preliminary report.

PURPOSE: [(18)F] fluorodeoxyglucose positron emission tomography (FDG PET) imaging has been shown to be valuable in early detection of persistent and recurrent head-and-neck cancer after treatment. Previous studies have reported its use in patients treated with conventional radiation. Many patients are now treated with intensity-modulated radiation treatment (IMRT). We evaluated the value of FDG PET in the assessment of treatment response and surveillance in head-and-neck cancer patients treated with IMRT. METHODS AND MATERIALS: We performed a retrospective review of 85 head-and-neck cancer patients treated with IMRT at our institution between December 2000 and September 2003 who had FDG PET in their follow-up. Of these, 58 were treated with primary IMRT with or without chemotherapy, and 27 were treated with postoperative IMRT. RESULTS: Sixty-four patients had negative initial FDG PET after treatment. Forty of them, who had 6 to 24 months of follow-up after the imaging study, had no evidence of local or regional recurrence, although three of them developed distant disease. Twenty-one patients had a positive initial FDG PET after treatment, with 11 positive at the primary site, 9 positive in the neck, and 3 positive distantly. Six of 11 patients with a positive FDG PET at the primary site were true positive, and 3 had salvage surgery. Eight of 9 patients positive in the neck had a salvage neck dissection. One had fine needle aspiration of the lymph node with positive cytology but refused surgery later. For patients with follow-up of 6 months and longer, only 1 of 45 patients with a negative initial FDG PET at the primary site developed a local recurrence. None of 49 patients with a negative initial FDG PET in the neck developed a regional recurrence. Two cases are presented in which abnormal FDG PET preceded laryngoscopy or computed tomography in detection of tumor recurrences. CONCLUSIONS: FDG PET is useful in the posttreatment management of head-and-neck cancer patients treated with IMRT. It is highly accurate in the detection of persistent and recurrent disease after treatment and allows salvage treatment to be initiated in a timely manner. It also provides prognostic information concerning the risk of recurrence after curative therapy.

Severity assessment in acute paraquat poisoning by analysis of APACHE II score.

BACKGROUND AND PURPOSE: Several methods have been proposed to predict prognosis in patients with paraquat poisoning, but all have their limitations. This retrospective study evaluated the usefulness of Acute Physiology and Chronic Health Evaluation (APACHE) II scores in risk stratification for patients with paraquat poisoning. METHODS: Data from 58 adults with a diagnosis of paraquat poisoning presenting to a general hospital over a 10-year period were analyzed. APACHE II scores were calculated at 24 hours after admission and data on related parameters during the first 24 hours were collected for study. RESULTS: The overall in-hospital mortality was 72.4% and mortality in the intensive care unit was 82.2%. APACHE II scores were higher in non-survivors (n = 42, 23.3 +/- 12.4) than in survivors (n = 16, 6.7 +/- 4.1; p < 0.001). All 26 patients (44.8%) who received mechanical ventilation died. Of the 32 patients who received hemoperfusion, 25 (78.1%) died. Plasma paraquat concentration, estimated ingested amount of paraquat, and APACHE II score were significantly higher in non-survivors than in survivors (p < 0.05 for all comparisons). There were significant correlations between APACHE II score and the following variables: plasma paraquat concentration, estimated ingested amount of paraquat, and the peak values during the first 24 hours after admission for fraction of inspired oxygen, alveolar-arterial oxygen gradient, aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen, and serum creatinine (p < 0.05 for all comparisons). Higher APACHE II score was associated with greater mortality. All patients who had an APACHE II score greater than 20 died before discharge. CONCLUSIONS: This study has demonstrated that the APACHE II score is positively correlated with plasma paraquat concentration and ingested amount of paraquat. An APACHE II score of 20 or higher is a good predictor of in-hospital mortality.