Flight of an aeroplane with solid-state propulsion.

Since the first aeroplane flight more than 100 years ago, aeroplanes have been propelled using moving surfaces such as propellers and turbines. Most have been powered by fossil-fuel combustion. Electroaerodynamics, in which electrical forces accelerate ions in a fluid1,2, has been proposed as an alternative method of propelling aeroplanes-without moving parts, nearly silently and without combustion emissions3-6. However, no aeroplane with such a solid-state propulsion system has yet flown. Here we demonstrate that a solid-state propulsion system can sustain powered flight, by designing and flying an electroaerodynamically propelled heavier-than-air aeroplane. We flew a fixed-wing aeroplane with a five-metre wingspan ten times and showed that it achieved steady-level flight. All batteries and power systems, including a specifically developed ultralight high-voltage (40-kilovolt) power converter, were carried on-board. We show that conventionally accepted limitations in thrust-to-power ratio and thrust density4,6,7, which were previously thought to make electroaerodynamics unfeasible as a method of aeroplane propulsion, are surmountable. We provide a proof of concept for electroaerodynamic aeroplane propulsion, opening up possibilities for aircraft and aerodynamic devices that are quieter, mechanically simpler and do not emit combustion emissions.

Salvianolic Acid B Inhibits Oxidative Stress in Glomerular Mesangial Cells Alleviating Diabetic Nephropathy by Regulating SIRT3/FOXO1 Signaling.

INTRODUCTION: Oxidative stress is pivotal in advancing diabetic nephropathy (DN). Salvianolic acid B (SAB), derived from Radix Salviae miltiorrhizae, exhibits renoprotective effects. However, the mechanisms underlying its action in DN are not fully elucidated. This study explores SAB's protective effect on DN, focusing on its antioxidative properties in glomerular mesangial cells. METHODS: The renoprotective effects of various SAB dosages on DN rats were assessed by evaluating kidney tissue pathological alterations through hematoxylin and eosin, periodic acid-Schiff, Masson, TUNEL staining, and kidney function through biochemical detection. Cell counting kit-8 and lactate dehydrogenase cytotoxicity assays were utilized to evaluate the viability of high glucose (HG)-induced HBZY-1 cells treated with various SAB dosages. Oxidative stress and inflammation levels were measured using enzyme-linked immunosorbent assay kits. The Sirtuin 3 (SIRT3)/Forkhead box transcription factor O1 (FOXO1) pathway was examined through Western blot and immunohistochemistry. RESULTS: SAB mitigated kidney histopathological alterations and function and cell apoptosis in DN rats at various dosages. It enhanced the activity of glutathione peroxidase and superoxide dismutase while decreasing reactive oxygen species and malondialdehyde levels both in vivo and in vitro. SAB also suppressed the levels of pro-inflammatory cytokines (IL-1ß, IL-6, MCP-1, and TNF-α) and the expression of collagen IV and fibronectin in HG-induced HBZY-1 cells. Furthermore, SAB activated the SIRT3/FOXO1 signaling pathway. CONCLUSION: Our findings suggest that SAB may alleviate oxidative stress in DN both in vivo and in vitro, potentially through the activation of the SIRT3/FOXO1-mediated signaling pathway. This study provides initial insights into the possible antioxidative and renoprotective effects of SAB, indicating its potential utility as a therapeutic agent for DN.

Effect of integrated intervention to prevent child drowning in rural areas of Guangdong, China: a cluster randomized controlled trial.

BACKGROUND: Drowning is the leading cause of death for children under the age of 15 years in Guangdong Province, China. This serious public health issue also exists in low- and middle-income countries (LMICs), which have few value-integrated intervention programs. The current study presents an integrated intervention project that aims to explore an effective pattern of prevention for child drowning in rural areas and feasibility to perform in other LMICs. METHODS: We conducted a cluster randomized controlled trial by comparing the incidence of non-fatal drowning among children in two groups in rural areas of southern China. We recruited the participants in two phases and reached a total of 10 687 students from 23 schools at two towns in Guangdong Province, China. At the first and second phases, 8966 and 1721 students were recruited, respectively. RESULTS: The final evaluation questionnaires were collected after 18 months of integrated intervention, where we obtained 9791 data from Grades 3-9. The incidence of non-fatal drowning between the intervention and control groups after intervention did not differ significantly from the baseline according to the total number of students, male students, female students and Grades 6-9 [0.81; 95% confidence interval (CI): [0.66, 1.00]; p = 0.05, 1.17; 95% CI: [0.90, 1.51]; p = 0.25, 1.40; 95% CI: [0.97, 2.02]; p = 0.07 and 0.97; 95% CI: [0.70, 1.34]; p = 0.86], except for Grades 3-5 (1.36; 95% CI: [1.02, 1.82]; p = 0.037). The study observed a significantly positive benefit of awareness and risk behaviours of non-fatal drowning between the intervention and control groups (0.27, 95% CI: [0.21, 0.33]; p = 0.00, -0.16; 95% CI: [-0.24, -0.08]; p = 0.00). CONCLUSIONS: The integrated intervention exerted a significant impact on the prevention and management of child non-fatal drowning, especially in rural areas.

Iron-Catalyzed Highly Enantioselective Hydrogenation of Alkenes.

Here, we reported for the first time an iron-catalyzed highly enantioselective hydrogenation of minimally functionalized 1,1-disubstituted alkenes to access chiral alkanes with full conversion and excellent ee. A novel chiral 8-oxazoline iminoquinoline ligand and its iron complex have been designed and synthesized. This protocol is operationally simple by using 1 atm of hydrogen gas and shows good functional group tolerance. A primary mechanism has been proposed by the deuterium-labeling experiments.

Trends and external causes of traumatic brain injury and spinal cord injury mortality in south China, 2014-2018: an ecological study.

BACKGROUND: The epidemiological evidence of traumatic brain injury (TBI) and spinal cord injury (SCI) mortality in mainland China is lacking. We aimed to assess the trends of TBI and SCI mortality, and their association with sex, age, location and external causes of injury in south China. METHODS: Mortality data were derived from the Disease Surveillance Points (DSPs) system of Guangdong province between 2014 and 2018. We examined the trends in mortality with Cochran-Armitage trend test, and the association between the socio-demographic factors and the TBI and SCI mortality by using negative binomial models. Subgroup analysis was performed by stratifying the external causes of TBI and SCI. RESULTS: The age-standardized TBI mortality remained relatively stable (from 11.6 to 15.4 per 100,000), while the SCI mortality increased by 148.3% from 2014 to 2018. Compared with females and urban residents, the adjusted mortality rate ratios of males and rural residents were 2.3 and 2.0 for TBI, and 2.2 and 4.6 for SCI, respectively. TBI and SCI mortality increased substantially with age. Motor vehicle crashes and falls were the leading causes of TBI mortality in residents aged under 75 years and over 75 years, respectively. Falls were the most important external cause for SCI death of all ages. CONCLUSIONS: Being male, rural and elderly residents are at higher risk of dying from TBI and SCI. The substantial burden of TBI and SCI caused by road traffic crashes and falls has called for the urgent need to improve injury prevention, pre-hospital aid, hospital treatment and recovery.

An exploratory model for the non-fatal drowning risks in children in Guangdong, China.

BACKGROUND: Drowning is a leading cause of accidental death in children under 14 years of age in Guangdong, China. We developed a statistical model to classify the risk of drowning among children based on the risk factors. METHODS: A multiple-stage cluster random sampling was employed to select the students in Grades 3 to 9 in two townships in Qingyuan, Guangdong. Questionnaire was a self-reported measure consisting of general information, knowledge, attitudes and activities. A univariate logistic regression model was used to preliminarily select the independent variables at a P value of 0.1 for multivariable model. Three-quarters of the participants were randomly selected as a training sample to establish the model, and the remaining were treated as a testing sample to validate the model. RESULTS: A total of 8390 children were included in this study, about 12.18% (1013) experienced drowning during the past one year. In the univariate logistic regression model, introvert personality, unclear distributions of water areas on the way to school, and bad relationships with their classmates and families were positively associated with drowning. However, females, older age and lower swimming skills were negatively associated with drowning. After employing the prediction model with these factors to estimate drowning risk of the students in the testing samples, the results of Hosmer-Lemeshow tests showed non-significant differences between the predictive results and actual risk (χ2 = 5.97, P = 0.65). CONCLUSIONS: Male, younger children, higher swimming skills, bad relationship with their classmates and families, introvert personality and unclear distributions of water areas on the way to school were important risk factors of non-fatal drowning among children. The prediction model based on these variables has an acceptable predictive ability.

Epidemiological characteristics of injury mortality in Guangdong Province, China, 2015.

BACKGROUND: As the fourth leading cause of death, injury is an important public health concern in Guangdong Province, China. The epidemiological characteristics of injury mortality is changing along with the social development. This study described the epidemiological characteristics of injury mortality in Guangdong Province by analyzing the death surveillance data in a few areas in Guangdong Province in 2015. METHODS: Using the mortality data from the Disease Surveillance Points (DSP) system, injury deaths were classified according to the International Classification of Disease-10th Revision (ICD-10). The data were stratified by areas (urban/rural), gender, age groups, injury types, and then overall and type-specific injury mortality rates were estimated for the whole Guangdong Province, China. RESULTS: We estimated that about 38,200 individuals died from injury in Guangdong Province in 2015, producing a mortality rate of 43.11/100,000. The overall age-standardized injury mortality in men was higher in rural areas compared with urban areas (41.29/100,000 versus 24.89/100,000). In terms of injury intent, unintentional injuries were the commonnest injury type, which accounted for 83.93% of the overall injury deaths, however, the deaths caused by suicide should not be ignored, which occupied 12.67% of the total injury deaths. In terms of injury cause type, falls, road-traffic accidents, suicide, drowning, and accidental poisoning were the top five leading types of injury deaths. CONCLUSIONS: In Guangdong Province, injury is an important cause of death. Road-traffic accidents, falls, suicide, drowning, and accidental poisoning should be the priorities of intervention. Moreover, in rural areas, the men were the most targeted subpopulation of the prevention activities.

Downregulation of lncRNA XLOC_032768 in diabetic patients predicts the occurrence of diabetic nephropathy.

LncRNA XLOC_032768 is reported to prevent renal tubular epithelial cells from cisplatin-induced apoptosis, suggesting its involvement in the development of kidney injury. The present study aimed to explore the role of XLOC_032768 in diabetic nephropathy (DN). The present study enrolled a total of 140 healthy controls (Control group) and 140 patients with type 2 diabetes (Diabetes group). Expression of XLOC_032768 in plasma from these participants was analyzed by performing RT-qPCR. The 140 diabetic patients were followed up for 5 years to monitor the occurrence of diabetic complications. The role of XLOC_032768 in predicting the occurrence of diabetic complications, including DN, diabetic cardiomyopathy (DC), diabetic retinopathy (DR), and diabetic foot (DF) were analyzed by plotting receiver operating characteristic curves and complication-free curves. On the day of admission, plasma levels of XLOC_032768 were not significantly different between Control and Diabetes groups. During follow-up, a total of 22, 15, 13, and 15 cases were diagnosed as DN, DC, DR, and DF, respectively. On the day of diagnosis, plasma levels of XLOC_032768 were only decreased in DN group, but not in other groups, compared to plasma levels of XLOC_032768 on the day of admission. Using plasma levels of XLOC_032768 on the day of admission as a biomarker, potential DN patients were effectively separated from patients with other potential complications and diabetic patients without complications. The 140 diabetic patients were grouped into high and low XLOC_032768 level groups. It was observed that low XLOC_032768 level group showed increased occurrence of DN, but not other complications, compared to high XLOC_032768 level group. Therefore, the downregulation of lncRNA XLOC_032768 in diabetic patients may predict the occurrence of DN.

Enhancing osseointegration of titanium implants through MC3T3-E1 protein-gelatin polyelectrolyte multilayers.

Titanium and its alloys have found extensive use in the biomedical field, however, implant loosening due to weak osseointegration remains a concern. Improved surface morphology and chemical composition can enhance the osseointegration of the implant. Bioactive molecules have been utilized to modify the surface of the titanium-based material to achieve rapid and efficient osseointegration between the implant and bone tissues. In this study, the bioactive substance MC3T3-E1 protein-gelatin polyelectrolyte multilayers were constructed on the surface of the titanium implants by means of layer-by-layer self-assembly to enhance the strength of the bond between the bone tissue and the implant. The findings of the study indicate that the layer-by-layer self-assembly technique can enhance surface roughness and hydrophilicity to a considerable extent. Compared to pure titanium, the hydrophilicity of TiOH LBL was significantly increased with a water contact angle of 75.0 ± $$ \pm $$ 2.4°. The modified titanium implant exhibits superior biocompatibility and wound healing ability upon co-culture with cells. MC3T3-E1 cells were co-cultured with TiOH LBL for 1, 3, and 5 days and their viability was higher than 85%. In addition, the wound healing results demonstrate that TiOH LBL exhibited the highest migratory ability (243 ± 10 µm). Furthermore, after 7 days of osteogenic induction, the modified titanium implant significantly promotes osteoblast differentiation.

Improving osseointegration and antimicrobial properties of titanium implants with black phosphorus nanosheets-hydroxyapatite composite coatings for vascularized bone regeneration.

For decades, titanium implants have shown impressive advantages in bone repair. However, the preparation of implants with excellent antimicrobial properties as well as better osseointegration ability remains difficult for clinical application. In this study, black phosphorus nanosheets (BPNSs) were doped into hydroxyapatite (HA) coatings using electrophoretic deposition. The coatings' surface morphology, roughness, water contact angle, photothermal properties, and antibacterial properties were investigated. The BP/HA coating exhibited a surface roughness of 59.1 nm, providing an ideal substrate for cell attachment and growth. The water contact angle on the BP/HA coating was measured to be approximately 8.55°, indicating its hydrophilic nature. The BPNSs demonstrated efficient photothermal conversion, with a temperature increase of 42.2°C under laser irradiation. The BP/HA composite coating exhibited a significant reduction in bacterial growth, with inhibition rates of 95.6% and 96.1% against Staphylococcus aureus and Escherichia coli. In addition, the cytocompatibility of the composite coating was evaluated by cell adhesion, CCK8 and AM/PI staining; the effect of the composite coating in promoting angiogenesis was assessed by scratch assay, transwell assay, and protein blotting; and the osteoinductivity of the composite coating was evaluated by alkaline phosphatase assay, alizarin red staining, and Western blot. The results showed that the BP/HA composite coating exhibited superior performance in promoting biological functions such as cell proliferation and adhesion, antibacterial activity, osteogenic differentiation, and angiogenesis, and had potential applications in vascularized bone regeneration.

Lymphatic vessels: roles and potential therapeutic intervention in rheumatoid arthritis and osteoarthritis.

Lymphatic vessel networks are a main part of the vertebrate cardiovascular system, which participate in various physiological and pathological processes via regulation of fluid transport and immunosurveillance. Targeting lymphatic vessels has become a potent strategy for treating various human diseases. The presence of varying degrees of inflammation in joints of rheumatoid arthritis (RA) and osteoarthritis (OA), characterized by heightened infiltration of inflammatory cells, increased levels of inflammatory factors, and activation of inflammatory signaling pathways, significantly contributes to the disruption of cartilage and bone homeostasis in arthritic conditions. Increasing evidence has demonstrated the pivotal role of lymphatic vessels in maintaining joint homeostasis, with their pathological alterations closely associated with the initiation and progression of inflammatory joint diseases. In this review, we provide a comprehensive overview of the evolving knowledge regarding the structural and functional aspects of lymphatic vessels in the pathogenesis of RA and OA. In addition, we summarized the potential regulatory mechanisms underlying the modulation of lymphatic function in maintaining joint homeostasis during inflammatory conditions, and further discuss the distinctions between RA and OA. Moreover, we describe therapeutic strategies for inflammatory arthritis based on lymphatic vessels, including the promotion of lymphangiogenesis, restoration of proper lymphatic vessel function through anti-inflammatory approaches, enhancement of lymphatic contractility and drainage, and alleviation of congestion within the lymphatic system through the elimination of inflammatory cells. At last, we envisage potential research perspectives and strategies to target lymphatic vessels in treating these inflammatory joint diseases.

Hyaluronic acid mediated Fe3O4 nanocubes reversing the EMT through targeted cancer stem cell.

Hepatocellular carcinoma (HCC) is one of the deadliest tumors in the world with a high rate of recurrence and metastasis. Therefore, the most pressing issue today is the development of new drugs, diagnostic and therapeutic approaches for effective cancer treatment. Cancer stem cells (CSCs) play a pivotal role in tumor recurrence, tumor resistance, and tumor metastasis, which provides a new perspective on the development of liver cancer. In the study, a high-temperature thermal breakdown approach was used to create composite magnetic nanocubes modified by polyethyleneimine (PEI) and hyaluronic acid (HA). The Fe3O4 nanocubes can recognize HCC stem cells via receptor-ligand binding of HA and CD44 (HA receptor). While loading a small molecule LDN193189 inhibited the expression of stemness-related genes OCT4 and Nanog. More crucially, the Fe3O4 nanocubes significantly suppressed HCC cell proliferation and migration by regulating the expression of epithelial-mesenchymal transition (EMT) process markers E-cadherin, Vimentin, and N-cadherin. Dual targeting using magnetic and receptor-mediated targeting improved the uptake of the drug delivery system. Our findings imply that the medication delivery method might be a potential therapeutic strategy for HCC.

Calcium Phosphate Bone Cements Incorporated with Black Phosphorus Nanosheets Enhanced Osteogenesis.

For decades, calcium phosphate bone cements (CPCs) showed impressive advantages for their good biocompatibility, injectability, and osteoconductivity in the bone repair field. However, it is still difficult to prepare CPCs with outstanding antibacterial and self-curing properties, sufficient phosphorus release, and osteoinductivity for clinical application. Herein, we used partially crystallized calcium phosphate and dicalcium phosphate anhydrate particles incorporated with black phosphorous nanosheets to prepare calcium phosphate bone cements (CPCs). The curing time, compressive strength, photothermal properties, and degradation performance of BP/CPC were investigated. In addition, the cytocompatibility and osteoinductivity of BP/CPC were evaluated by cell adhesion, cytotoxicity, alkaline phosphatase detection, alizarin red staining, and western blot assay. The results indicated that BP/CPC showed adjustable curing time, good cytocompatibility, outstanding photothermal properties, and osteoinductivity, suggesting their potential application for bone regeneration.

Absence of toll-like receptor 7 ameliorates survival and reduces intestinal injury in mice after Clostridium difficile infection.

Clostridioides difficile (CD) is a major cause of antibiotic-associated diarrhea and pseudomembranous enteritis. C. difficile infection (CDI) is increasingly present in the community and represents a significant burden on the healthcare system. Identification of novel immune-based therapeutic targets from a better understanding of their molecular pathogenesis is urgently required. Toll-like receptor 7 (TLR7) is an important pattern recognition receptor and function as an immune sensor that can trigger host defenses against pathogens, but the relationship between TLR7 and CDI remains unknown. Here, we reported that the expression levels of TLR7 increased significantly in patients and mice with CDI. Absence of TLR7 in mice with CDI demonstrated enhanced bacterial clearance of intestinal contents and reduced intestinal inflammation, edema, injury and prolonged the survival. TLR7 loss decreased the concentrations of tumor necrosis factor (TNF)-α, interferon (IFN)-γ and IFN-α1 in the intestine and improved tissue damage and inflammation. Flow cytometry and immunofluorescence results indicated that TLR7 enhanced leukocyte recruitment in the infected intestine. In-vitro results have shown that TLR7 impairs the phagocytosis and killing ability of macrophages to CD, prompts reactive oxygen species (ROS) production and accelerates apoptosis. To our knowledge, our study first identified TLR7 as a critical factor that contributes to the immunopathology of CDI, suggesting that targeting TLR7 might serve as a potential treatment for CDI.

Bifunctional electrospun poly (L-lactic acid) membranes incorporating black phosphorus nanosheets and nano-zinc oxide for enhanced biocompatibility and antibacterial properties in catheter materials.

For several decades, urinary tract infections caused by catheter-associated devices have negatively impacted not only medical device utilization, but also patient health. As such, the creation of catheter materials with both superior biocompatibility and antibacterial properties has become necessary. This study aimed to produce electrospun membranes based on polylactic acid (PLA) with the incorporation of black phosphorus nanosheets (BPNS) and nano-zinc oxide (nZnO) particles, as well as a mixture of both, in order to design bifunctional membranes with enhanced bioactivity and antibacterial features. The optimum spinning process was determined through examination of various PLA mass concentrations, spinning solution propelling speeds, and receiving drum rotating speeds, with emphasis on the mechanical properties of PLA membranes. Additionally, the antibacterial properties and cytocompatibility of the ZnO-BP/PLA antibacterial membranes were explored. Results demonstrated that the ZnO-BP/PLA antibacterial membranes displayed a rich porous structure, with uniform distribution of nZnO particles and BPNS. With the increase of polylactic acid concentration and the decrease of spinning solution advancing and drum rotation speeds, the mechanical properties of the fiber membrane were significantly improved. Furthermore, the composite membranes exhibited remarkable photothermal therapy (PTT) capabilities when aided by the synergistic effect of BP nanosheets and ZnO. This was achieved through near-infrared (NIR) irradiation, which not only dissipated the biofilm but also enhanced the release capability of Zn2+. Consequently, the composite membrane demonstrated an improved inhibitory effect on both Escherichia coli and Staphylococcus aureus. The results of cytotoxicity and adhesion experiments also indicated good cytocompatibility, with cells growing normally on the surface of the ZnO-BP/PLA antibacterial membrane. Overall, these findings validate the utilization of both BPNS and n-ZnO fillers in the creation of novel bifunctional PLA-based membranes, which possess both biocompatibility and antibacterial properties for interventional catheter materials.

Cross-sectional study on prevalence and risk factors for falls among the elderly in communities of Guangdong province, China.

OBJECTIVE: This study aims to investigate the prevalence and risk factors of falls among the elderly in Guangdong, China. METHODS: A cross-sectional study was conducted in six communities of Guangdong province. People over 60 years old were selected with multistage random-cluster sampling. Data on falls within the previous 12 months and fall-related risk factors were collected through a face-to-face interview. RESULTS: The prevalence of falls among older adults was 11.9% (95% CI: 11.0% to 12.8%) among 5374 interviewees. The common injuries caused by falls were bruises/scrapes (40.0%) and fractures (15.5%), and most people fall while doing housework (35.0%). Univariate analysis showed that 14 factors were associated with falls among older adults, including gender, age, residence, occupation, education level, balance ability, situation of cognition, disease, depression, living arrangement, marital status, the behaviour of exercise, drinking and drug use (p<0.05). Multivariate analysis showed that the associated factors of falls among older adults included woman (OR=1.68, 95% CI: 1.40 to 2.02), age from 70 to 79 years (OR=1.31, 95% CI: 1.09 to 1.58), age over 80 (OR=1.63, 95% CI: 1.25 to 2.13), impaired balance ability (OR=1.45, 95% CI: 1.20 to 1.75), exercise several times per month (OR=1.69, 95% CI: 1.13 to 2.53), polypharmacy (OR=1.54, 95% CI: 1.19 to 2.00), cognition impairment (OR=1.35, 95% CI: 1.08 to 1.69), mild depression (OR=1.89, 95% CI: 1.47 to 2.45) and moderate depression (OR=3.07, 95% CI: 1.99 to 4.73). CONCLUSIONS: The hazards caused by falls to the elderly in China cannot be ignored. A multidimensional customised fall prevention programme should be considered to reduce the risk of falls among the elderly based on the results above.

Non-Fatal Drowning Risk Prediction Based on Stacking Ensemble Algorithm.

Drowning is a major public health problem and a leading cause of death in children living in developing countries. We seek better machine learning (ML) algorithms to provide a novel risk-assessment insight on non-fatal drowning prediction. The data on non-fatal drowning were collected in Qingyuan city, Guangdong Province, China. We developed four ML models to predict the non-fatal drowning risk, including a logistic regression model (LR), random forest model (RF), support vector machine model (SVM), and stacking-based model, on three primary learners (LR, RF, SVM). The area under the curve (AUC), F1 value, accuracy, sensitivity, and specificity were calculated to evaluate the predictive ability of the different learning algorithms. This study included a total of 8390 children. Of those, 12.07% (1013) had experienced non-fatal drowning. We found the following risk factors are closely associated with the risk of non-fatal drowning: the frequency of swimming in open water, distance between the school and the surrounding open waters, swimming skills, personality (introvert) and relationality with family members. Compared to the other three base models, the stacking generalization model achieved a superior performance in the non-fatal drowning dataset (AUC = 0.741, sensitivity = 0.625, F1 value = 0.359, accuracy = 0.739 and specificity = 0.754). This study indicates that applying stacking ensemble algorithms in the non-fatal drowning dataset may outperform other ML models.

Nonfatal child pedestrian injury in two urban cities of Guangdong Province, China: results from a cross-sectional survey.

OBJECTIVE: To describe the epidemiological characteristics of nonfatal child pedestrian injuries and provide information to help understand an important public-health problem. METHODS: This was a school-based, cross-sectional questionnaire survey. The sample (42 750 children) was obtained from two urban cities of Guangdong Province, China, using multi-stage randomized sampling. Information was collected by the respondents self-reporting in the classroom. RESULTS: The incidence rate of nonfatal child pedestrian injuries in the cities was 2.0%. Boys had a higher incidence rate (2.6%) than girls (1.4%). Compared to other children, those aged 10 years are at the highest risk. The primary places of occurrence were sidewalks, residential roads, and crosswalks. High-risk behavior of the children immediately prior to injury included mid-block crossings, playing on roads, and crossing on red lights. The major vehicles that caused pedestrian injuries were bicycles, car or vans, and motorcycles. Bruises, fractures, and injuries to the internal organs were the top three types of injuries. Almost 40% of victims were hospitalized, and nearly 30% of the victims suffered long-term disabilities. CONCLUSION: This study shows that nonfatal child pedestrian injuries are a very serious public-health problem in the urban cities of Guangdong. Based on the epidemiological characteristics, prevention strategies and further research should be carried out to reduce the occurrence of injuries.

[Association between distorted weight perception and suicide ideation among normal weight adolescents].

OBJECTIVE: To explore the relationship between distorted weight perception and suicide ideation among normal weight adolescents in Guangdong province. METHODS: This study used the data of Guangdong Provincial Youth Health Risk Behavior Survey in 2004 and 2007. To identify the association between distorted weight perception and suicide ideation, a logistic regression analysis was performed. The effects of age, economic status, mother's education, mental health, and depression were also adjusted. RESULTS: A total of 12 729 people participated in this study, 6096 males and 6633 females. The prevalence of suicide ideation among normal weight adolescents was 13.58% (1729/12 729) in the past 12 months, with higher prevalence in girls (16.15%, 1071/6633) than that in boys (10.79%, 658/6096) (χ(2) = 77.71, P = 0.00). It was common that the adolescents misperceived their weight. Only 44.93% (5719/12 729) of normal weight students correctly perceived their body weight while 43.52% (5540/12 729) of them overestimated their weight and 11.43% (1455/12 729) underestimated their weight. The distorted weight perception in girls (65.58%, 4350/6633) was higher than that in boys (43.39%, 2645/6096) (χ(2) = 993.91, P = 0.00). Distorted weight perception was significantly associated with suicide ideation after controlling for factors age, economic status, mother's education, mental health, and depression. The students who overestimate their body weight were more likely to have suicide ideation than that who correctly perceived their weight (OR = 1.43, 95%CI: 1.27 - 1.61). CONCLUSION: The prevalence of distorted weight perception was high and it significantly associated with suicide ideation.

Absence of Toll-like receptor 7 protects mice against Pseudomonas aeruginosa pneumonia.

Toll-like receptor 7 (TLR7) is a sensor of microbial ssRNA that participates in the immune response process in many diseases. We herein sought to establish the role of TLR7 in Pseudomonas aeruginosa pneumonia. Pneumonia model was created by intratracheally injecting Pseudomonas aeruginosa and the effects of TLR7 on survival, bacterial burden, lung pathology, cytokine and chemokine production, and pulmonary leukocyte recruitment were measured after Pseudomonas aeruginosa challenge. TLR7 expression was significantly elevated in WT mice after Pseudomonas aeruginosa infection. TLR7-/- mice demonstrated enhanced survival, bacterial clearance, leukocyte infiltration, and macrophages phagocytic activity, and decreased pathology and capillary leakage. Besides, improved survival and bacterial clearance were observed in WT mice treated with TLR7 antagonist IRS661. More importantly, lack of TLR7 suppressed pro-inflammatory cytokine production and induced anti-inflammatory cytokine production in mice lungs. Finally, neutralized IL-10 damaged the bacterial clearance ability of TLR7 deficient mice, leading to decreased survival. Collectively, absence of TLR7 provided protective effects during Pseudomonas aeruginosa pneumonia and suggested that TLR7 could act as a novel immune target to treat clinical cases with Pseudomonas aeruginosa pneumonia.