Vascular endothelial growth factor (VEGF) is considered as a prime mediator of angiogenesis and has been implicated in carcinogenesis and metastasis. Various studies examined the relationship between VEGF overexpression with the clinical outcome in patients with osteosarcoma but yielded conflicting results. Electronic databases updated to April 2013 were searched to find relevant studies. A meta-analysis was conducted with eligible studies which quantitatively evaluated the relationship between VEGF overexpression and survival of patients with osteosarcoma. Survival data were aggregated and quantitatively analyzed. We performed a meta-analysis of eight studies that evaluated the correlation between VEGF overexpression and survival in patients with osteosarcoma. Combined hazard ratios suggested that VEGF overexpression had an unfavorable impact on overall survival (hazard ratio (HR) = 1.75, 95% confidence interval (CI): 1.21-2.28) in patients with osteosarcoma for overall populations, 2.37 (1.35-3.39) in Asian studies but not in non-Asian studies (HR = 1.51, 95% CI: 0.89-2.14). No significant heterogeneity was observed among all studies. VEGF overexpression indicates a poor prognosis for patients with osteosarcoma. However, the prognostic value of VEGF on survival in osteosarcoma patients still needs further large-scale prospective trials to be clarified.

The construction of the Qinghai-Tibet railroad provided a unique opportunity to study the relation between intermittent altitude exposure and acute mountain sickness (AMS). For 5 yr, workers spent 7-month periods at altitude interspaced with 5-month periods at sea level; the incidence, severity, and risk factors of AMS were prospectively investigated. Six hundred lowlanders commuted for 5 yr between near sea level and approximately 4500 m and were compared to 600 other lowland workers, recruited each year upon their first ascent to high altitude as newcomers, and to 200 Tibetan workers native to approximately 4500 m. AMS was assessed with the Lake Louise Scoring System. The incidence and severity of AMS in commuters were lower upon each subsequent exposure, whereas they remained similar in newcomers each year. AMS susceptibility was thus lowered by repeated exposure to altitude. Repeated exposure increased resting Sao(2) and decreased resting heart rate. Tibetans had no AMS, higher Sao(2), and lower heart rates. In conclusion, repetitive 7-month exposures increasingly protect lowlanders against AMS, even when interspaced with 5-month periods spent at low altitude, but do not allow attaining the level of adaptation of altitude natives.

It takes ≈24 h to travel the ≈3000-km-long Qinghai–Tibet railroad of which 85% is situated above 4000 m with a pass at 5072 m. Each year about 2 million passengers are rapidly exposed to high altitude traveling on this train. The aim of this study was to quantify the occurrence of altitude illness on the train. Three subject groups were surveyed: 160 Han lowlanders, 62 Han immigrants living at 2200 to 2500 m, and 25 Tibetans living at 3700 to 4200 m. Passengers reached 4768 m from 2808 m in less than 1.5 h, after which 78% of the passengers reported symptoms, 24% reaching the Lake Louise criterion score for AMS. AMS incidence was 31% in nonacclimatized Han compared to 16% in Han altitude residents and 0% in Tibetans. Women and older subjects had a slightly greater risk for AMS. Most cases of AMS were mild and self-limiting, resolving within days upon arrival in Lhasa. Some cases of more severe AMS necessitated medical attention. To curb the health risk of rapid travel to altitude by train, prospective travelers should be better informed, medical train personnel should be well trained, and staged travel with 1 to 2 days at intermediate altitudes should be suggested to nonacclimatized subjects.

Calcium phosphate cement (CPC) has been widely used in orthopedic and dental applications. A critical limitation of CPC is low strength and high susceptibility to severe fracture. Surgeons can use it only to reconstruct non-stress bearing bone, raising the need for a tougher new generation of CPC. Fibers have been used as a reinforcement of CPC to improve the strength of a pure CPC scaffold. The RGD peptides (Arg-Gly-Asp) have been used to improve the biocompatibility of the scaffold, via physical adsorption. The purpose of this study was to develop a novel CPC scaffold reinforced by RGD peptide-bearing chitosan fibers (RGD-fiber-CPC). Our data showed that the RGD-fiber-CPC scaffold had an increased flexural strength, and stimulated new bone formation in an animal model. The RGD-fiber-CPC is a novel bone graft substitute in orthopedic surgery.