Banking of perinatal mesenchymal stem/stromal cells for stem cellbased personalized medicine over lifetime:Matters arising

Mesenchymal stromal/stem cells(MSCs)are currently applied in regenerative medicine and tissue engineering.Numerous clinical studies have indicated that MSCs from different tissue sources can provide therapeutic benefits for patients.MSCs derived from either human adult or perinatal tissues have their own unique advantages in their medical practices.Usually,clinical studies are conducted by using of cultured MSCs after thawing or short-term cryopreserved-then-thawed MSCs prior to administration for the treatment of a wide range of diseases and medical disorders.Currently,cryogenically banking perinatal MSCs for potential personalized medicine for later use in lifetime has raised growing interest in China as well as in many other countries.Meanwhile,this has led to questions regarding the availability,stability,consistency,multipotency,and therapeutic efficiency of the potential perinatal MSC-derived therapeutic products after longterm cryostorage.This opinion review does not minimize any therapeutic benefit of perinatal MSCs in many diseases after short-term cryopreservation.This article mainly describes what is known about banking perinatal MSCs in China and,importantly,it is to recognize the limitation and uncertainty of the perinatal MSCs stored in cryobanks for stem cell medical treatments in whole life.This article also provides several recommendations for banking of perinatal MSCs for potentially future personalized medicine,albeit it is impossible to anticipate whether the donor will benefit from banked MSCs during her/his lifetime.

Use of low-dose computed tomography to assess pulmonary tuberculosis among healthcare workers in a tuberculosis hospital

Background:According to the World Health Organization,China is one of 22 countries with serious tuberculosis(TB)infections and one of the 27 countries with serious multidrug-resistant TB strains.Despite the decline of tuberculosis in the overall population,healthcare workers(HCWs)are still at a high risk of infection.Compared with high-income countries,the TB prevalence among HCWs is higher in low-and middle-income countries.Low-dose computed tomography(LDCT)is becoming more popular due to its superior sensitivity and lower radiation dose.However,there have been no reports about active pulmonary tuberculosis(PTB)among HCWs as assessed with LDCT.The purposes of this study were to examine PTB statuses in HCWs in hospitals specializing in TB treatment and explore the significance of the application of LDCT to these workers.Methods:This study retrospectively analysed the physical examination data of healthcare workers in the Beijing Chest Hospital from September 2012 to December 2015.Low-dose lung CT examinations were performed in all cases.The comparisons between active and inactive PTB according to the CT findings were made using the Pearson chi-square test or the Fisher’s exact test.Comparisons between the incidences of active PTB in high-risk areas and non-high-risk areas were performed using the Pearson chi-square test.Analyses of active PTB were performed according to different ages,numbers of years on the job,and the risks of the working areas.Active PTB as diagnosed by the LDCT examinations alone was compared with the final comprehensive diagnoses,and the sensitivity and positive predictive value were calculated.Results:A total of 1012 participants were included in this study.During the 4-year period of medical examinations,active PTB was found in 19 cases,and inactive PTB was found in 109 cases.The prevalence of active PTB in the participants was 1.24%,0.67%,0.81%,and 0.53%for years 2012 to 2015.The corresponding incidences of active PTB among the tuberculosis hospital participants were 0.86%,0.41%,0.54%,and 0.26%.Most HCWs with active TB(78.9%,15/19)worked in the high-risk areas of the hospital.There was a significant difference in the incidences of active PTB between the HCWs who worked in the high-risk and non-high-risk areas(odds ratio[OR],14.415;95%confidence interval(CI):4.733-43.896).Comparisons of the CT signs between the active and inactive groups via chi-square tests revealed that the tree-in-bud,cavity,fibrous shadow,and calcification signs exhibited significant differences(P=0.000,0.021,0.001,and 0.024,respectively).Tree-in-bud and cavity opacities suggest active pulmonary tuberculosis,whereas fibrous shadow and calcification opacities are the main features of inactive pulmonary tuberculosis.Comparison with the final comprehensive diagnoses revealed that the sensitivity and positive predictive value of the diagnoses of active PTB based on LDCT alone were 100%and 86.4%,respectively.Conclusions:Healthcare workers in tuberculosis hospitals are a high-risk group for active PTB.Yearly LDCT examinations of such high-risk groups are feasible and necessary.