Comparative analysis of the quality of platelet concentrates produced by apheresis procedures, platelet rich plasma, and buffy coat.

BACKGROUND: Platelet concentrates (PCs) could be prepared using either whole-blood processes or apheresis instruments. During collection, processing and storage, some biochemical and functional changes occur, which may result in quality reduction. Quality evaluation of PCs may be helpful for the precise control of platelet (PLT) inventory to reduce the risk of refractoriness and adverse effects caused by platelet transfusion. STUDY DESIGN AND METHODS: The study was aimed to evaluate the quality of PCs which were produced by five processes: apheresis (AP) procedures (using three different cell separators: Amicus, Trima Accel and MCS+ instruments), platelet rich plasma (PRP), and buffy coat (BC). A total of 100 PCs (20 of each group) were assessed in respect of routine quality control, morphology, size distribution, destroyed and activated platelets, and production of platelet-derived microparticles (PMPs). RESULTS: All PCs have satisfied the recommended quality of volume, platelet count, residual WBC count, residual RBC count, pH, and sterility according to the Chinese Technical Manual. There was no difference among the 5 groups in morphology and size of PLT and PMPs. Dynamic light scattering test showed that apheresis PCs showed peaks around 10-20 nm, but not whole blood-derived PCs. PCs prepared by Amicus had the relatively high percentage of destroyed platelet, activated platelets and PMPs than other groups. DISCUSSION: The data suggested high heterogeneity of PMPs, destroyed and activated platelets in PCs produced by different processes, which might be helpful to manage the platelet inventory for targeted use.

Seroprevalence and risk factors on Syphilis among blood donors in Chengdu, China,from 2005 to 2017.

BACKGROUND: High-risk population of blood donation increases the prevalence of transmit blood-borne diseases and harm the blood safety. Syphilis accounts for approximately 10% of commonly sexually transmitted diseases. The risk factors for blood donors infected with syphilis are also risk factors for other blood borne diseases. The objective of the study is to investigate the seroprevalence and risk factors on syphilis among blood donors, and analyze the donation status of high-risk population. METHODS: A retrospective study was conducted in Chengdu Blood Center during 2005 and 2017. Serological test results of volunteer blood donors were collected. Conditional logistic regression models were performed to investigate syphilis-related risk factors and population attributable risk (PAR) was performed to predict the tendencies of high-risk populations' on risky behaviors. RESULTS: The serological epidemic for syphilis among blood donors in Chengdu showed an upward trend from 2005 to 2017.TP positive blood donors were more likely to have multiple sexual partners and commercial sex (50.6% vs.22.6, 11.1% vs.4.6%). Multiple condition logistic regression model denoted the following risk factors for increasing rates of syphilis infections: multiple sexual partners (OR = 7.1, 95% CI:1.72-6.58), razor reuse (OR = 1.7;, 95% CI:1.01-2.01); ear piercing (OR = 2.7, 95% CI:1.48-3.37); tattoo (OR = 3.3, 95% CI:1.17-6.78); condom occasionally (OR = 2.8, 95% CI:0.68-1.66). The PAR for each of the risk factors were 0.225, 0.144, 0.147, 0.018, 0.129, 0.018, respectively. CONCLUSION: Health consultation and screening of high-risk groups before blood donation need to be further improved. Blood donor recruitment should emphasize on excluding the high-risk donors and recruiting more low-risk blood donors. In addition, this study also shows that sharing cosmetic surgical instrument has been proven to transmit blood-borne diseases. Therefore, the syphilis in blood circulation should not be ignored.

The estimation of prevalence and risk factors of hepatitis B virus infection among blood donors in Chengdu, China.

The reported positive rates of hepatitis B virus surface antigen (HBsAg) among Chinese blood donors generally do not include data from pre-donation rapid tests. The aim of this study was to estimate the prevalence of serologic markers for HBsAg and risk factors among blood donors from Chengdu, China. From April 2010 to March 2011, a total of 16,875 blood donors were enrolled. Data from HBsAg tests before and after donations were collected to estimate the prevalence of HBsAg. A case-control study was conducted in 265 unique HBsAg-positive blood donors and 530 seronegative donors between January 2011 and October 2012. The odds ratio (OR) and 95% confidence interval (CI) were calculated using conditional logistic regression. The population attributable risk (PAR) was estimated. The prevalence of HBsAg was 3.17% (95%CI, 2.91-3.43%). The following risk factors were associated with HBV infection: non-vaccination for HBV (OR = 4.236; 95%CI, 2.72-6.60%), razor sharing (OR = 2.370; 95%CI, 1.46-3.84%), dental treatment (OR = 1.714; 95%CI, 1.21-2.43%), acupuncture (OR = 1.983; 95%CI, 1.20-3.28%), a family history of HBV infection (OR = 2.257; 95%CI, 1.32-3.86%), and endoscopy (OR = 2.17; 95%CI, 1.04-4.51%). The PAR values of the risk factors were 42.77%, 31.78%, 13.68%, 6.18%, 6.09%, and 2.85%, respectively, and the total PAR was 68.78%. The prevalence of HBsAg among Chinese blood donors is still high. HBV vaccinations can provide protection. Blood contact from sharing instruments is still a high risk route of transmission for HBV. Immunization programs and behavioral interventions should be used to prevent blood donation infections and improve blood safety.

[Amplification efficency and optimization of culture conditions of γδ T cells in peripheral blood by different phosphate compounds].

OBJECTIVE: To compare the efficiency of pamidronate (PAM) and isopentenyl pyrophosphate (IPP) to stimulate γδ T cell expansion from human peripheral blood and explore the optimized expansion conditions. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated by Ficoll-Paque gradient centrifugation, and then cultured in RPMI1640 medium supplemented with 10% fetal bovine serum, IPP (1.0, 5.0, 10.0, 15.0 µg/mL) or PAM (2.0, 5.0, 8.0, 12.0 µg/mL), and IL-2 (100.0, 200.0, 500.0 IU/mL). The cells were observed and collected. The number and proportion of CD3⁺TCRδ2⁺ γδ T cells stimulated by PAM or IPP in total lymphocytes were evaluated by flow cytometry and the expansion efficiency was calculated. RESULTS: After 14 days, the ratios of γδ T cells in total lymphocytes in IPP group and PAM group increased to 81.3% and 78.5%, respectively. This indicated that both IPP and PAM could effectively stimulate γδ T cell expansion and there was no significant difference in the efficiency of expansion between the two groups (P>0.05). CONCLUSION: PAM has the similar ability with IPP to stimulate γδ T cell expansion in vitro. PAM could become more economical and practical choice for stimulating γδ T cell expansion.

Prevalence of and risk factors for hepatitis C virus infection among blood donors in Chengdu, China.

The objectives of the study were to estimate the prevalence of anti-hepatitis C virus (HCV) positivity among blood donors from Chengdu, China, and to determine risk factors associated with infection. In this study, data were collected from volunteer blood donors between July 2006 and June 2007. Anti-HCV test was performed in 119,518 donors. To identify risk factors associated with HCV infections a case-control study was conducted in 305 unique HCV-seropositive blood donors and 610 seronegative donors matched for age and sex. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression. The population attributable risk (PAR) to risk factor was estimated according to the Bruzzi's formula. The prevalence of anti-HCV positivity was 0.53% (95% CI: 0.489-0.572%). The final multivariate model included the following independent HCV risk factors: razor sharing (OR=29.16; 95% CI: 12.89-66.00), blood transfusion (OR=20.84; 95% CI: 3.76-115.45), acupuncture (OR=8.01; 95% CI: 3.16-20.30), a history of hospitalization, injections >10 years earlier, a family history of hepatitis B, dental treatment, and ear piercing. The PAR of risk factors are 68.4%, 6.3%, 14.1%, 23.1%, 29.5%, 29.3%, 38.9%, and 27.8%, respectively, and the total PAR is 98.3%. Infection with HCV among blood donors in Chengdu is associated with iatrogenic risk factors and beauty treatment-related risk. Razor sharing is an important risk factor for HCV infection. These results indicate that infection control measures in healthcare settings may reduce the burden of HCV infection and there is a need for development of effective educational programs to improve HCV knowledge among beauty culture professionals, barber cosmetologists, and the general public to avoid risk behaviors.

[Effectiveness of an intervention on sharing razors among rural migrant construction workers].

OBJECTIVE: To evaluate a behavioral intervention designed to reduce share use of razors among rural migrant workers. METHODS: A total of 591 rural migrant construction workers in Chengdu were recruited in a randomized controlled trial. Information and skill training was provided to the intervention group to encourage them to refuse share use of razors. RESULTS: Sixty days after the intervention, 61.38% of workers in the intervention group had refused share use of razors in barber shops, significantly more than those in the control group (22.26%). The odds ratio was 3.647 (95% CI = 2.242, 5.934). The workers in the intervention group showed better knowledge on the concept, transmission and prevention of blood-borne infectious diseases than those in the control group. CONCLUSION: Behavioral intervention is effective in reducing share use of razors in barber shops among rural migrant workers. The intervention may need to be improved for sustaining a long term result.