The articular cartilage collagen network is an important research focus because network disruption results in cartilage degeneration and patient disability. The recently introduced helium ion microscope (HIM), with its smaller probe size, longer depth of field and charge neutralization, has the potential to overcome the inherent limitations of electron microscopy for visualization of collagen network features, particularly at the nanoscale. In this study, we evaluated the capabilities of the helium ion microscope for high-resolution visualization of the articular cartilage collagen network. Images of rabbit knee cartilage were acquired with a helium ion microscope; comparison images were acquired with a field emission scanning electron microscope (FE-SEM) and a transmission electron microscope (TEM). Sharpness of example high-resolution helium ion microscope and field emission scanning electron microscope images was quantified using the 25-75% rise distance metric. The helium ion microscope was able to acquire high-resolution images with unprecedented clarity, with greater sharpness and three-dimensional-like detail of nanoscale fibril morphologies and fibril connections, in samples without conductive coatings. These nanoscale features could not be resolved by field emission scanning electron microscopy, and three-dimensional network structure could not be visualized with transmission electron microscopy. The nanoscale three-dimensional-like visualization capabilities of the helium ion microscope will enable new avenues of investigation in cartilage collagen network research.

Background There is little data on HIV prevalence, incidence or residual risks for transfusion transmitted HIV infection among Chinese blood donors. Methods Donations from five Chinese blood centers in 2008–2010 were screened using two rounds of ELISA testing for anti-HIV-1/2. A reactive result in either or both rounds led to Western Blot confirmatory testing. HIV prevalence and demographic correlates among first time donors, incidence rate and demographic correlates among repeat donors were examined. Weighted multivariable logistic regression analysis examined correlates of HIV confirmatory status among first time donors. Residual risks for transfusion transmitted HIV infection were evaluated based on incidence among repeat donors. Results Among 821,320 donations, 40% came from repeat donors.1,837 (0.34%) first time and 577 (0.17%) repeat donations screened reactive for anti-HIV-1/2, among which 1,310 and 419 were tested by Western Blot. 233 (17.7%) first time and 44 (10.5%) repeat donations were confirmed positive. Estimated prevalence was 66 infections per 100,000 (95% CI: 59–74) first time donors. Estimated incidence was 9/100,000 (95% CI: 7–12) person-years among repeat donors. Weighted multivariable logistic regression analysis indicate that first time donors 26–45 years old were 1.6–1.8 times likely to be HIV positive than those 25 years and younger. Donors with some college or above education were less likely to be HIV positive than those with middle school education, ORs ranging from 0.35 to 0.60. Minority were 1.6 times likely to be HIV positive than Han majority donors (OR: 1.6; CI: 1.2–2.1). No difference in prevalence was found between gender. Current HIV TTI residual risk was 5.4 (1.2–12.5) infections per million whole blood donations. Conclusion Despite the declining HIV epidemic China, estimated residual risks for transfusion transmitted HIV infection are still high, highlighting the potential blood safety yield of NAT implementation in donation screening.

Background It is important to understand donor return behavior. Converting first time donors to become repeat donors is essential for maintaining an adequate blood supply. Methods Characteristics of 241,552 whole blood (WB) donations from first time (FT) and repeat (RPT) donors who donated in 2008 at the 5 blood centers in China were compared. A subset of 54,394 WB donors who donated between January 1 and March 31, 2008 were analyzed for their return behavior in 2008 following the index donation using logistic regression. Results Of all donations, 64% was from FT donors. Donors with self-reported previous donations tended to be male, older, married, donated larger volume (≥300mL), and were heavier in weight. Among donors who donated from January to March, 2008, 14% returned for subsequent WB donations by the end of 2008. The number of previous donations and blood collection location were the two strongest predictors for making subsequent donations. Donors with 1, 2–3 and more than 3 previous donations were 3.7, 5.7, and 11.0 times more likely to return than FT donors. Those who donated in a blood collection vehicle were 4 times more likely to return than those who donated at a blood center. Being female, younger and of a lower education level (≤ middle school) were positively associated with subsequent return blood donation during the follow-up period observed in this study. Conclusion Most of the Chinese blood supply is from first time donors. Strategies aimed at encouraging current donors to become repeat donors are needed.

Timely donations in response to a disaster are crucial to ensure emergency blood transfusion. The dramatically increased postearthquake donations suggest that Chinese blood centers are capable of handling emergency blood needs. Measures to maintain blood safety should be taken in times of emergency.

Bioceramics are an important subclass of inorganic, non-metallic biomaterials. Attributing to their bioactivity and the ability to form bonds with native bone, bioceramics are increasingly used in medical implants, especially for bone repair and regeneration. With chemical composition similar to that of native bone, hydroxyapatite (HAp), a type of bioceramics, may impart to biomaterial implants biocompatibility, osteoconductivity, as well as surface properties that are germane to osteointegration at the bone-implant interface. However, porous bioceramics are very brittle and have low fracture toughness and compressive strength, which limits their uses as bulk materials for orthopedic implants. Increasing their mechanical strength by reducing the porosity may prevent tissue infiltration, therefore, bone regeneration. In comparison, polymers may mimic the mechanical properties of native bone, however, may lack the appropriate surface properties to seamlessly integrate with natural bone. There is a critical need to combine the bulk properties of polymers with the surface properties of bioceramics in the design of functional scaffolds for bone tissue engineering. There are several ways to incorporate bioceramics on scaffold surfaces, including plasma spraying, sputter coating, physical adsorption, laser deposition, and biomineralization. Biomineralization, which allows easy fabrication of bioceramics under physiological conditions, provides an effective means to produce bonelike minerals, e.g., HAp, on scaffold surfaces. By following the cascade of biological mineralization in vivo, biomineralization in vitro on polymers may be achieved using several different methods, including immersion in simulated body fluid (SBF), alternative soaking in calcium and phosphate solutions, urea-mediated solution mineralization, enzymatic method, and direct incorporation of HAp nanoparticles into polymers. The uniformity, structure, and composition of the bioceramic coatings can be fine-tuned by governing bimineralization parameters such as composition and concentration of the immersion solution, immersion time, temperature, and agitation. A variety of surface modification techniques can be chosen to functionalize/activate polymer surfaces to facilitate biomineralization. In this review, the mechanism for biomineralization in vivo, different mechanisms and methods for biomineralization in vitro, surface modifications for enhanced biomineralization, polymers for biomineralization, and biomineralization for drug delivery will be discussed in details.

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Our analysis suggests that the characteristics of AP donations in China are different from WB donations and differ among the five Chinese blood centers. Some of the differences are likely due to different recruitment policies. Further studies should be conducted to understand what motivates Chinese blood donors to participate as AP donors.

The extent to which the free-vaccine policy impacts the initiation and completion of a hepatitis B vaccine series is poorly understood. The aim of this study was to evaluate the impact of the free-vaccine policy on hepatitis B vaccination. A provincial survey was conducted in 2006 in Fujian Province, south-east of China, where the free-vaccine policy for hepatitis B was announced in 2002 and implemented in 2003. A total of 1628 children were investigated, and 1443 (88.6%) were included in this analysis. Among the children studied, 55.2% were vaccinated within 24 h of birth, and 76.1% completed the hepatitis B vaccine series on time. The rate of hepatitis B surface antibody positivity increased from 29.9% among children born in 1992 to 90.5% among children born in 2005, while the corresponding HBV infection rate decreased from 30.4% to 1.72%. Logistic regression indicated that, compared to children born between 1996 and 2001, the odds ratios (ORs) for timely initiation were 2.57 (95% confidence interval [CI], 1.71-3.84), 5.24 (95% CI, 3.26-8.43) and 9.06 (95% CI, 4.48-18.34) among children born in 2003, 2004 and 2005, respectively; the corresponding ORs for completing the vaccine series were 4.23 (95% CI, 1.97-9.10), 3.76 (95% CI, 1.81-7.82) and 4.94 (95% CI, 1.74-14.00) among children born in 2003, 2004 and 2005, respectively. Children with delayed vaccine initiation (>24 h after birth) were less likely to complete the vaccine series than those who received a timely first dose (OR = 0.02, 95% CI, 0.005-0.09). The impact of the free-vaccine policy on vaccine initiation and vaccine series completion did not differ by children's residence area (rural vs urban). As hypothesized, the odds of completing the vaccine series increased after the free-vaccine policy was announced in 2002 among children with delayed initiation (>24 h after birth) but not among those with timely initiation (≤ 24 h after birth). In conclusion, the free-vaccine policy significantly improved the timely initiation and completion of the vaccine series. The impact of this policy on completion of the vaccine series was larger among children with delayed vaccine initiation.