Abstract In this paper, the penetration resistance of 6061 aluminum plates to explosively formed projectiles (EFPs) at the incidence angles of 0°, 15°, 30°, and 45° was studied. The penetration process was roughly divided into three typical stages—the plastic flanging stage of the target, the righting stage of the projectile, and the plug formation stage of the target. Through the energy analysis, the energy consumption of the aluminum plate increased with the increase in the incidence angle during the entire penetration process. Through the microscopic analysis of the perforated wall surface of the aluminum plate, it was found that there were distinct boundaries and differences between the plastic reaming zone and the punching plug fracture zone.. Overall, four kinds of classification modes were proposed for the damage of the aftereffect plate, which provides a method to evaluate the aftereffect of EFP oblique penetration into 6061 aluminum plates.

RESUMO Introdução O treino de resistência é considerado um meio eficaz para aumento de força e a velocidade. Objetivo Explorar as repercussões do treino de resistência aquática sobre a estabilidade dinâmica dos atletas de vôlei. Métodos 20 atletas de primeiro nível nacionais de vôlei masculino, foram divididos aleatoriamente em um grupo de treinamento para controle e outro grupo experimental com reforço utilizando treino de resistência aquático. O tempo do experimento foi de 10 semanas. Ao final, foram comparadas força muscular do membro inferior, capacidade de salto, estabilidade dinâmica, dor muscular. Foram verificados também os efeitos residuais em seis semanas após o término do experimento. Resultados O grupo de treino de resistência aquática parou de treinar por 6 semanas, com pico de torque a 60°/s, 180°s de extensão relativa do joelho, a altura de salto, o balanço completo dos braços e as três fases do salto em altura foram significativamente melhores do que o teste primário; a velocidade de entrada na água na direção vertical também foi significativamente melhor uma semana após o treinamento. Conclusão O treino de resistência aquático pode melhorar significativamente a estabilidade dinâmica dos membros inferiores e seu efeito pode ser mantido até 6 semanas após o término. Recomenda-se aplicar o treino de aprimoramento da resistência para manter o condicionamento físico, especialmente por longos períodos. Nível de evidência II; Estudos Terapêuticos - Investigação de Resultados.

ABSTRACT Introduction Resistance training is considered a practical pathway for increasing strength and speed. Objective Explore the aquatic resistance training on the dynamic stability in volleyball athletes. Methods Using aquatic resistance training reinforcement, 20 first-level national male volleyball athletes were randomly divided into control and experimental groups. The time of the experiment was ten weeks. In the end, lower limb muscle strength, jumping ability, dynamic stability, and muscle pain were compared. Residual effects were also checked six weeks after the end of the experiment. Results The aquatic resistance training group stopped training for six weeks, peak torque at 60°/s, 180°s of relative knee extension, jump height, full arm swing, and all three phases of the high jump were significantly better than the preliminary test; water entry speed in the vertical direction was also significantly better one week after training. Conclusion Aquatic resistance training can significantly improve the dynamic stability of the lower limbs, and its effect can be maintained up to 6 weeks after completion. It is recommended to apply resistance enhancement training to maintain fitness, especially for long periods. Evidence Level II; Therapeutic Studies - Investigating the result.

RESUMEN Introducción El entrenamiento de resistencia se considera una forma eficaz de aumentar la fuerza y la velocidad. Objetivo Explorar las repercusiones del entrenamiento de resistencia acuática en la estabilidad dinámica de los atletas de voleibol. Métodos 20 atletas masculinos de voleibol de primer nivel nacional, fueron divididos aleatoriamente en un grupo de entrenamiento de control y otro grupo experimental con refuerzo mediante entrenamiento de resistencia acuática. El tiempo del experimento fue de 10 semanas. Al final, se comparó la fuerza muscular de las extremidades inferiores, la capacidad de salto, la estabilidad dinámica y el dolor muscular. También se comprobaron los efectos residuales a las seis semanas de finalizar el experimento. Resultados El grupo de entrenamiento de resistencia acuática dejó de entrenar durante 6 semanas, el pico máximo de torque a 60°/s, la extensión relativa de la rodilla a 180°s, la altura del salto, el balanceo completo del brazo y las tres fases del salto de altura fueron significativamente mejores que en la prueba primaria; la velocidad de entrada al agua en la dirección vertical también fue significativamente mejor una semana después del entrenamiento. Conclusión El entrenamiento de resistencia acuática puede mejorar significativamente la estabilidad dinámica de los miembros inferiores y su efecto puede mantenerse hasta 6 semanas después de su realización. Se recomienda aplicar un entrenamiento de mejora de la resistencia para mantener la forma física, especialmente durante largos periodos. Nivel de evidencia II; Estudios terapéuticos - Investigación de resultados.

Abstract Background: UVB irradiation can cause acute damage such as sunburn, or photoaging and melanoma, all of which are major health threats. Objective: This study was designed to investigate the mechanism of skin photoaging induced by UVB radiation in mice through the analysis of the differential expression of miRNAs. Methods: A UVB irradiation photoaging model was constructed. HE and Masson special stains were used to examine the modifications in the epidermis and dermis of mice. The miRNA expression profiles of the mouse skin model exposed to UVB radiation and the normal skin of mice were analyzed using miRNA-sequence analysis. GO and Pathway analysis were employed for the prediction of miRNA targets. Results: A total of 23 miRNAs were evaluated for significantly different expressions in comparison to normal skin. Among them, 7 miRNAs were up-regulated and 16 were down-regulated in the skin with photoaging of mice exposed to UVB irradiation. The differential expression of miRNA is related to a variety of signal transduction pathways, among which mmu-miR-195a-5p and mitogen-activated protein kinase (MAPK) signal pathways are crucial. There was a significant differential expression of miRNA in the skin of normal mice in comparison with the skin with photoaging induced by UVB irradiation. Study limitations: Due to time and energy constraints, the specific protein level verification, MAPK pathway exploration, and miR-195a-5p downstream molecular mechanism need to be further studied in the future. Conclusions: UVB-induced skin photoaging can be diagnosed and treated using miRNA.

A novel recognition method was put forward to identify the producing areas of the flue-cured tobacco leaves rapidly and non-destructively by using a near-infrared (NIR) spectrometer and a multi-layer-extreme learning machine (ML-ELM) algorithm. In contrast to traditional linear discriminant analysis (LDA) and extreme learning machine (ELM) algorithms, the accuracy, sensitivity and specificity were the highest for the proposed ML-ELM algorithm. The ML-ELM models for different producing areas of Yunnan tobacco leaves had the best generalization ability and prediction results. Besides, the above three algorithms were also identified by using the chemical index data. The experimental results indicated that the NIR spectroscopy technology together with ML-ELM algorithm achieved the best prediction performance both using the NIR spectral data and chemical index data. It indicates that the combination of NIR and ML-ELM can recognize different producing areas of Yunnan tobacco leaves rapidly, accurately, and non-destructively.

Abstract To investigate the effect of polyurea on the protective performance of a steel target plate under the combination of shock wave and fragments, the failure characteristics, damage process and micro mechanism of the polyurea coated steel plates with different coating methods under the combination of explosion shock waves and fragments were analyzed through experiments and numerical simulations. The results showed that single-sided coatings aggravated the damage of target plate when the coating thickness was 2 mm. While the polyurea thickness greater than 4 mm could significantly reduce the damage degree of the steel plate. When the polyurea was coated on the double sides, it would aggravate the damage, no matter how thick the polyurea was. Through microscopic research, it was found that the front coated polyurea was severely ablated by detonation products, which greatly reduce its energy absorption efficiency. The polyurea coated on the back underwent tensile fracture under the influence of tensile stress wave. The breaking of intramolecular hydrogen bond of polyurea was the key to the energy absorption of polyurea.

Abstract In this paper, LS-dyna software was used to simulate the charging process of cylindrical shell when EFP has different angles, and some interesting phenomena and laws were found. Cylindrical elastic wave σr was generated when the cylindrical shell was impacted by EFP. The cylindrical elastic wave σr was correlated with the time required for the cylindrical shell charge to be successfully detonated. When the EFP warhead penetration Angle θ ranges from 0° to 10°, the σr increases linearly with (cosθ)-1/2. With the increase of θ, the tangential velocity vy had an obvious effect on the impact of EFP on the cylindrical shell, and the linear relationship between the elastic wave σr and (cosθ)-1/2 does not change. When the θ was greater than 45°, EFP could not successfully impact and detonate the cylindrical shell charge. The EFP velocity was measured by velocity measurement method with an error of 1.3%. The experimental results have strong similarity with the simulation results, indicating that the parameters of the numerical simulation model have good reliability.

Abstract In this study, through animal experiments, we investigated the effects of Qingli Gandan decoction on the IL-23/IL-17 signalling pathway and the expression of CD4+/IL-17A+ cells in EAU rats. We then predicted the potential mechanisms of the action. First, Lewis rats were divided using the random number table method into a (1) control group, (2) model group and (3) TCM group. The TCM group was given a Qingli Gandan prescription by gavage after an intervention model. Next, blood, aqueous humour and vitreous were collected from each group on days 4, 8, 12, 16 and 20 after immunisation. An enzyme linked immunosorbent assay (ELISA) was used to detect the protein concentrations of IL-17 and IL-23 in a serum, aqueous humour and vitreous of rats on different immunisation days, and the percentage of CD4+/IL-17A+ cells in rat spleen was detected by flow cytometry. The peak concentration of serum IL-17 protein in group 3 was statistically lower than that in group 2 (P < 0.05) on days 4, 8 and 12 of immunisation. However, the peak concentration of serum IL-23 protein in group 3 was statistically lower than in group 2 (P < 0.05) on days 8 and 12 of immunisation; in addition, on days 8 and 12, the protein concentrations of IL-23 and IL-17 in the aqueous humour group 3 were all lower than those in group 2. On days 4, 8 and 12, the protein concentrations of IL-23 and IL-17 in vitreous in group 3 were significantly lower than those in group 2. We found that the proportion of CD4+/IL-17A+ cells in the groups 2 and 3 increased on day 8 compared with group 1 (P < 0.05). The proportion of CD4+/IL-17A+ cells decreased in group 3 compared with group 2 (P < 0.05).At last, we think Qingli Gandan can reduce the onset of EAU in rats and treat it, presumably because of inhibiting the IL-23/IL-17 axis. It may inhibit the expression of CD4+/IL-17A+ cells and play a role in inhibiting the IL-23/IL-17 signalling pathway.

SUMMARY: The Wnt pathway is essential for the initiation of lizard tail regeneration. The regenerated lizard tails exhibit obvious morphological differences compared to the original ones. The expression of Wnt1 and Wnt2b proteins in the regenerating tail of Scincella tsinlingensis was detected by immunohistochemistry and then comparatively analyzed for ultrastructural changes in the original and regenerated spinal cord. The ependymal layer of the original spinal cord was pseudostratified with multiciliated cells and primary monociliated cells, while the cells of the ependymal layer of the regenerated spinal cord were organized in a monolayer with a few biciliated cells. Immunolocalization indicated that Wnt1 and Wnt2b were mainly distributed in the dermis near the original tail stump, spinal cord, and clot-positive migratory cells during Stage I, 0-1 days post-amputation (dpa). Wnt1 and Wnt2b were predominantly detected in the epaxial and hypaxial musculature near the original tail stump, wound epithelium, and spinal cord in the original tail during Stage II, 1-7 dpa. Mesenchymal cells and wound epithelium showed immunostaining during Stage III and IV, 7-15 dpa. The ependymal tubes contained these signaling proteins during Stage V and VI, 20- 30 dpa. Labeling was mainly observed in nearby regenerative blood vessels, ependymal cells, epaxial and hypaxial musculature in the apical epithelial layer (AEC) after 45-160 dpa. These findings indicated that Wnt1 and Wnt2b proteins presented primarily in regenerating epidermis and nerve tissues were a critical signal for tail regeneration in S. tsinlingensis.

RESUMEN: La vía Wnt es esencial para el inicio de la regeneración de la cola del lagarto. Las colas de lagarto regeneradas exhiben diferencias morfológicas obvias en comparación con las originales. La expresión de las proteínas Wnt1 y Wnt2b en la cola en regeneración de Scincella tsinlingensis se detectó mediante inmunohistoquímica y luego se analizaron comparativamente los cambios ultraestructurales en la médula espinal original y regenerada. La capa ependimaria de la médula espinal original se pseudoestratificó con células multiciliadas y células monociliadas primarias, mientras que las células de la capa ependimaria de la médula espinal regenerada se organizaron en monocapa con algunas células bicilicadas. La inmunolocalización indicó que Wnt1 y Wnt2b se distribuyeron principalmente en la dermis cerca del muñón de la cola original, la médula espinal y las células migratorias positivas en el coágulo durante la Etapa I, 0-1 días después de la amputación (dpa). Wnt1 y Wnt2b se detectaron predominantemente en la musculatura epaxial e hipaxial cerca del muñón de la cola original, el epitelio de la herida y la médula espinal en la cola original durante la Etapa II, 1-7 dpa. Las células mesenquimales y el epitelio de la herida mostraron inmunomarcaje durante la Etapa III y IV, 7- 15 dpa. Los tubos ependimarios contenían estas proteínas de señalización durante la Etapa V y VI, 20-30 dpa. El marcaje se observó principalmente en vasos sanguíneos regenerativos cercanos, células ependimarias, musculatura epaxial e hipaxial en la capa epitelial apical (AEC) después de 45-160 dpa. Estos hallazgos indicaron que las proteínas Wnt1 y Wnt2b están presentes principalmente en la epidermis en regeneración y en los tejidos nerviosos y eran una señal crítica para la regeneración de la cola en S. tsinlingensis.

Resumo Fundamento: A fração de ejeção (FE) tem sido utilizada em análises fenotípicas e na tomada de decisões sobre o tratamento de insuficiência cardíaca (IC). Assim, a FE tornou-se parte fundamental da prática clínica diária. Objetivo: Este estudo tem como objetivo investigar características, preditores e desfechos associados a alterações da FE em pacientes com diferentes tipos de IC grave. Métodos: Foram incluídos neste estudo 626 pacientes com IC grave e classe III–IV da New York Heart Association (NYHA). Os pacientes foram classificados em três grupos de acordo com as alterações da FE, ou seja, FE aumentada (FE-A), definida como aumento da FE ≥10%, FE diminuída (FE-D), definida como diminuição da FE ≥10%, e FE estável (FE-E), definida como alteração da FE <10%. Valores p inferiores a 0,05 foram considerados significativos. Resultados: Dos 377 pacientes com IC grave, 23,3% apresentaram FE-A, 59,5% apresentaram FE-E e 17,2% apresentaram FE-D. Os resultados mostraram ainda 68,2% de insuficiência cardíaca com fração de ejeção reduzida (ICFEr) no grupo FE-A e 64,6% de insuficiência cardíaca com fração de ejeção preservada (ICFEp) no grupo FE-D. Os preditores de FE-A identificados foram faixa etária mais jovem, ausência de diabetes e fração de ejeção do ventrículo esquerdo (FEVE) menor. Já os preditores de FE-D encontrados foram ausência de fibrilação atrial, baixos níveis de ácido úrico e maior FEVE. Em um seguimento mediano de 40 meses, 44,8% dos pacientes foram vítimas de morte por todas as causas. Conclusão: Na IC grave, a ICFEr apresentou maior percentual no grupo FE-A e a ICFEp foi mais comum no grupo FE-D.

Abstract Background: Ejection fraction (EF) has been used in phenotype analyses and to make treatment decisions regarding heart failure (HF). Thus, EF has become a fundamental part of daily clinical practice. Objective: This study aims to investigate the characteristics, predictors, and outcomes associated with EF changes in patients with different types of severe HF. Methods: A total of 626 severe HF patients with New York Heart Association (NYHA) class III–IV were enrolled in this study. The patients were classified into three groups according to EF changes, namely, increased EF (EF-I), defined as an EF increase ≥10%, decreased EF (EF-D), defined as an EF decrease ≥10%, and stable EF (EF-S), defined as an EF change <10%. A p-value lower than 0.05 was considered significant. Results: Out of 377 severe HF patients, 23.3% presented EF-I, 59.5% presented EF-S, and 17.2% presented EF-D. The results further showed 68.2% of heart failure with reduced ejection fraction (HFrEF) in the EF-I group and 64.6% of heart failure with preserved ejection fraction (HFpEF) in the EF-D group. The predictors of EF-I included younger age, absence of diabetes, and lower left ventricular ejection fraction (LVEF). The predictors of EF-D were absence of atrial fibrillation, lower uric acid level, and higher LVEF. Within a median follow-up of 40 months, 44.8% of patients suffered from all-cause death. Conclusion: In severe HF, HFrEF presented the highest percentage in the EF-I group, and HFpEF was most common in the EF-D group.

SUMMARY: The cutaneous wounds of trunk and tail healing scar-free or with scar were different in lizard species. Full- thickness cutaneous injuries of tail and body of Scincella tsinlingensis were examined by histomorphological and immunohistochemistrical methods. The results showed that all injuries healed without scarring. The process of the wound healing of S. tsinlingensis involved hemostasis, re-epithelialization, proliferation and remodelling, which also could be further subdivided into six stages. Stage I, 0-2 day post wound (dpw), the blood oozed gradually, no obvious wound contraction, minimal blood loss. Stage II, 2-10 dpw, the wound bed covered by the fibrin clot of blood, tissue fluid and tissue debris. Stage III, 7d-15 dpw, the wrinkled wound epitheliums was gradually stratified, and its surface was keratinized and exfoliated. Stage IV, 10-28 dpw, pigment cells were distributed at the boundary between epidermis and dermis, with few blood vessels and no granulation tissue formation. Stage V, 20-70 dpw, opaque scales covered the wound epithelium with randomly scattered melanophores in the base of the epidermis. Stage VI, 45-135 dpw, the epidermis and dermis restored to the thickness of the original skin. Regenerated scales were similar to scales of the uninjured dermis. The positive immunostaining of matrix metalloproteinases-9, cytokeratin 6, alpha smooth muscle actin, caspase 3 and transforming growth factor-β3 showed the specificity of healing period and different stages, which participated in skin wounds healing of S. tsinlingensis.

RESUMEN: En las diferentes especies de lagartos las heridas cutáneas del tronco y la cola sin cicatrices, o con algún tipo de cicatriz son diversas. En este estudio se examinaron las heridas cutáneas de espesor total de la cola y el cuerpo de Scincella tsinlingensis mediante métodos histomorfológicos e inmunohistoquímicos. Los resultados indicaron que todas las lesiones sanaron sin cicatrices visibles. El proceso de cicatrización de heridas de S. tsinlingensis implicó hemostasia, reepitelización, proliferación y remodelación, que también podrían subdividirse en seis etapas. Etapa I, 0-2 días después de la herida (dph), la sangre filtraba gradualmente, sin contracción evidente de la herida, con pérdida mínima de sangre. Etapa II, 2-10 dph, el lecho de la herida estaba cubierto por el coágulo de sangre, líquido tisular y restos tisulares de fibrina. Etapa III, 7-15 dph, los epitelios de la herida se estratificaron gradualmente y su superficie se queratiniza y exfolia. Etapa IV, 10-28 dph, las células pigmentarias se distribuyeron en el límite entre la epidermis y la dermis, con pocos vasos sanguíneos y sin formación de tejido de granulación. Etapa V, 20-70 dph, escamas opacas cubrieron el epitelio de la herida con melanóforos dispersos al azar en la base de la epidermis. Etapa VI, 45-135 dph, la epidermis y la dermis restauradas al grosor de la piel original. Las escamas regeneradas eran similares a las escamas de la dermis sin herida. La inmunotinción positiva de metaloproteinasas- 9 de matriz, citoqueratina 6, actina de músculo liso alfa, caspasa 3 y factor de crecimiento transformante-β3 mostró la especificidad del período de curación y las diferentes etapas, que participaron en la curación de heridas cutáneas de S. tsinlingensis.

Engeletin is a natural derivative of Smilax glabra rhizomilax that exhibits anti-inflammatory activity and suppresses lipid peroxidation. In the present study, we sought to elucidate the mechanistic basis for the neuroprotective and pro-angiogenic activity of engeltin in a human umbilical vein endothelial cells (HUVECs) oxygen-glucose deprivation and reoxygenation (OGD/R) model system and a middle cerebral artery occlusion (MCAO) rat model of cerebral ischemia and reperfusion injury. These analyses revealed that engeletin (10, 20, or 40 mg/kg) was able to reduce the infarct volume, increase cerebral blood flow, improve neurological function, and bolster the expression of vascular endothelial growth factor (VEGF), vasohibin-2 (Vash-2), angiopoietin-1 (Ang-1), phosphorylated human angiopoietin receptor tyrosine kinase 2 (p-Tie2), and platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31) in MCAO rats. Similarly, engeletin (100, 200, or 400 nM) markedly enhanced the migration, tube formation, and VEGF expression of HUVECs in an OGD/R model system, while the VEGF receptor (R) inhibitor axitinib reversed the observed changes in HUVEC tube formation activity and Vash-2, VEGF, and CD31 expression. These data suggested that engeletin exhibited significant neuroprotective effects against cerebral ischemia and reperfusion injury in rats, and improved cerebrovascular angiogenesis by modulating the VEGF/vasohibin and Ang-1/Tie-2 pathways.

Abstract TBX5 has been linked to Holt-Oram syndrome, with congenital heart defect (CHD) and atrial fibrillation (AF) being two major cardiac phenotypes. However, the prevalence of a TBX5 variation in patients with CHD and AF remains obscure. In this research, by sequencing analysis of TBX5 in 178 index patients with both CHD and AF, a novel heterozygous variation, NM_000192.3: c.577G>T; p.(Gly193*), was identified in one index patient with CHD and AF as well as bicuspid aortic valve (BAV), with an allele frequency of approximately 0.28%. Genetic analysis of the proband’s pedigree showed that the variation co-segregated with the diseases. The pathogenic variation was not detected in 292 unrelated healthy subjects. Functional analysis by using a dual-luciferase reporter assay system showed that the Gly193*-mutant TBX5 protein failed to transcriptionally activate its target genes MYH6 and NPPA. Moreover, the mutation nullified the synergistic transactivation between TBX5 and GATA4 as well as NKX2-5. Additionally, whole-exome sequencing analysis showed no other genes contributing to the diseases. This investigation firstly links a pathogenic variant in the TBX5 gene to familial CHD and AF as well as BAV, suggesting that CHD and AF as well as BAV share a common developmental basis in a subset of patients.

Reperfusion strategies in acute myocardial infarction (AMI) can cause a series of additional clinical damage, defined as myocardial ischemia/reperfusion (I/R) injury, and thus there is a need for effective therapeutic methods to attenuate I/R injury. miR-26a-5p has been proven to be an essential regulator for biological processes in different cell types. Nevertheless, the role of miR-26a-5p in myocardial I/R injury has not yet been reported. We established an I/R injury model in vitro and in vivo. In vitro, we used cardiomyocytes to simulate I/R injury using hypoxia/reoxygenation (H/R) assay. In vivo, we used C57BL/6 mice to construct I/R injury model. The infarct area was examined by TTC staining. The level of miR-26a-5p and PTEN was determined by bioinformatics methods, qRT-PCR, and western blot. In addition, the viability and apoptosis of cardiomyocytes were separately detected by MTT and flow cytometry. The targeting relationship between miR-26a-5p and PTEN was analyzed by the TargetScan website and luciferase reporter assay. I/R and H/R treatment induced myocardial tissue injury and cardiomyocyte apoptosis, respectively. The results showed that miR-26a-5p was down-regulated in myocardial I/R injury. PTEN was found to be a direct target of miR-26a-5p. Furthermore, miR-26a-5p effectively improved viability and inhibited apoptosis in cardiomyocytes upon I/R injury by inhibiting PTEN expression to activate the PI3K/AKT signaling pathway. miR-26a-5p could protect cardiomyocytes against I/R injury by regulating the PTEN/PI3K/AKT pathway, which offers a potential approach for myocardial I/R injury treatment.

ABSTRACT BACKGROUND: Osteosarcoma is the most prevalent malignant bone tumor in children and adolescents. Lung metastases are associated with poor prognosis. OBJECTIVE: The aim here was to explore the prevalence of and risk and prognostic factors for lung metastases in high-grade osteosarcoma patients. DESIGN AND SETTING: Retrospective cohort study based on the Surveillance, Epidemiology and End Results (SEER) database in the United States. METHODS: Data on 1,408 high-grade osteosarcoma patients registered in the SEER database between 2010 and 2015 were extracted. From these, all patients with high-grade osteosarcoma and initial lung metastasis were selected for analysis on risk and prognostic factors for lung metastases. Overall survival was estimated. RESULTS: There were 238 patients (16.90%) with lung metastases at diagnosis. Axial location, tumor size > 10 cm (odds ratio, OR 3.19; 95% confidence interval, CI: 1.58-6.45), higher N stage (OR 4.84; 95% CI: 1.94-12.13) and presence of bone metastases (OR 8.73; 95% CI: 4.37-17.48) or brain metastases (OR 25.63; 95% CI: 1.55-422.86) were significantly associated with lung metastases. Younger age and surgical treatment (hazard ratio, HR 0.46; 95% CI: 0.30-0.71) favored survival. Median survival was prolonged through primary tumor surgery. CONCLUSIONS: The factors revealed here may guide lung metastasis screening and prophylactic treatment for osteosarcoma patients. A primary tumor in an axial location, greater primary tumor size, higher lymph node stage and presence of bone or brain metastases were significantly correlated with lung metastases. The elderly group (≥ 60 years) showed significant correlation with poor overall survival. For improved survival among high-grade osteosarcoma patients with lung metastases, aggressive surgery on the primary tumor site should be encouraged.