Therapeutic hypothermia after perinatal asphyxia in Vietnam: medium-term outcomes at 18 months - a prospective cohort study.

AIM: To determine neurodevelopmental outcome at 18 months after therapeutic hypothermia for hypoxic-ischaemic encephalopathy (HIE) infants in Vietnam, a low-middle-income country. METHOD: Prospective cohort study investigating outcomes at 18 months in severely asphyxiated outborn infants who underwent therapeutic hypothermia for HIE in Hanoi, Vietnam, during the time period 2016-2019. Survivors were examined at discharge and at 6 and 18 months by a neonatologist, a neurologist and a rehabilitation physician, who were blinded to the infants' clinical severity during hospitalisation using two assessment tools: the Ages and Stages Questionnaire (ASQ) and the Hammersmith Infant Neurological Examination (HINE), to detect impairments and promote early interventions for those who require it. RESULTS: In total, 130 neonates, 85 (65%) with moderate and 45 (35%) with severe HIE, underwent therapeutic hypothermia treatment using phase change material. Forty-three infants (33%) died during hospitalisation and in infancy. Among the 87 survivors, 69 (79%) completed follow-up until 18 months. Nineteen children developed cerebral palsy (8 diplegia, 3 hemiplegia, 8 dyskinetic), and 11 had delayed neurodevelopment. At each time point, infants with a normal or delayed neurodevelopment had significantly higher ASQ and HINE scores (p<0.05) than those with cerebral palsy. CONCLUSION: The rates of mortality and adverse neurodevelopment rate were high and comparable to recently published data from other low-middle-income settings. The ASQ and HINE were useful tools for screening and evaluation of neurodevelopment and neurological function.

High Prevalence of Post-Traumatic Stress Disorder and Psychological Distress Among Healthcare Workers in COVID-19 Field Hospitals: A Cross-Sectional Study from Vietnam.

Objective: To evaluate the prevalence of post-traumatic stress disorder (PTSD) and other psychological disturbances in the Vietnamese healthcare workers (HCWs) at COVID-19 field hospitals. Methods: A cross-sectional study was conducted using the Impact of Event Scale-Revised (IES-R) to measure PTSD and the Depression Anxiety Stress scale (DASS) to measure other psychological disturbances. The anxiety about COVID-19 was evaluated by the fear of COVID-19 (FOC) scale. A self-developed questionnaire was used to assess work conditions and HCW's major concerns and preparedness. Ordinal logistic regression was used to identify factors associated with the severity of PTSD. A structural modeling equation (SEM) model was fitted to examine the correlation between PTSD and other psychological disturbances. Results: A total of 542 HCWs participated in this study. The prevalence of PTSD was 21.2%, most cases were mild. In the ordinal logistic regression analysis, a history of mental illness, poor preparedness, working in a condition with poor resources, a greater number of concerns, and greater fear of COVID-19 were independently associated with higher severity of PTSD. The prevalence of depression, anxiety, and stress was 46.8%, 38.3%, and 60.2, respectively. In the SEM model, PTSD and psychological disturbances had a strong correlation (standardized covariance 0.86). Conclusion: The prevalence of PTSD and other psychological disturbances was alarmingly high among HCWs who worked at COVID-19 field hospitals. The reported associated factors can be useful for policymakers and health authorities in the preparation for future pandemics.

Evaluation of Proliferation and Osteogenic Differentiation of Human Umbilical Cord-Derived Mesenchymal Stem Cells in Porous Scaffolds.

INTRODUCTION: Human umbilical cord-derived mesenchymal stem cells (UCMSCs) are multiple potential stem cells that can differentiate into various kinds of functional cells, including adipocytes, osteoblasts, and chondroblasts. Thus, UCMSCs have recently been used in both stem cell therapy and tissue engineering applications to produce various functional tissues. This study aimed to evaluate the proliferation and differentiation of UCMSCs on porous scaffolds. METHODS: UCMSCs were established in a previous study and kept in liquid nitrogen. They were thawed and expanded in vitro to yield enough cells for further experiments. The cells were characterized as having MSC phenotype. They were seeded onto culture medium-treated porous scaffolds or on non-treated porous scaffolds at different densities of UCMSCs (105, 2.1 × 105, and 5 × 105 cells/0.005 g scaffold). The existence of UCMSCs on the scaffold was evaluated by nucleic staining using Hoechst 33342 dye, while cell proliferation on the scaffold was determined by MTT assay. Osteogenic differentiation was evaluated by changes in cellular morphology, accumulation of extracellular calcium, and expression of osteoblast-specific genes (including runx2, osteopontin (OPN), and osteocalcin (OCN)). RESULTS: The data showed that UCMSCs could attach, proliferate, and differentiate on both treated and non-treated scaffolds but were better on the treated scaffold. At a cell density of 105 cells/0.005 g scaffold, the adherent and proliferative abilities of UCMSCs were higher than that of the other densities after 14 days of culture (p < 0.05). Adherent UCMSCs on the scaffold could be induced into osteoblasts in the osteogenic medium after 21 days of induction. These cells accumulated calcium in the extracellular matrix that was positive with Alizarin Red staining. They also expressed some genes related to osteoblasts, including runx2, OPN, and OCN. CONCLUSION: UCMSCs could adhere, proliferate, and differentiate into osteoblasts on porous scaffolds. Therefore, porous scaffolds (such as Variotis) may be suitable scaffolds for producing bone tissue in combination with UCMSCs.

Mental health problems both precede and follow bullying among adolescents and the effects differ by gender: a cross-lagged panel analysis of school-based longitudinal data in Vietnam.

BACKGROUND: The significant psychosocial harms from bullying among adolescents create major challenges for mental health promotion programs and services in schools. While the negative consequences of bullying victimisation are well known, to date there is scarce empirical analysis of inverse associations, in which mental health problems make children more vulnerable to bullying victimisation and perpetration. Based on a short-term longitudinal study among adolescents in Vietnam, this study examined reciprocal associations between children's depressive symptoms, psychological distress, suicidal ideation and bullying victimisation experiences (i.e., victims or bully-victims). METHODS: Secondary and high school students (n = 1167; age range: 11-16 years old; 55% female) in urban areas in northern Vietnam completed two self-administered questionnaires, 6-months apart in the academic year 2014-2015. Measures estimated bullying victimisation and perpetration in the past 6 months, depressive symptoms, psychological distress, and suicidal ideation. A cross-lagged analysis was performed to test the reciprocal associations. RESULTS: About one-third of students in the sample were involved as victims, bullies or bully-victims at both times, with more males than females reporting these experiences. Females reported a higher level of depressive symptoms than males at Time 1 but not at Time 2. After adjusting for outcome variables and other covariates measured at Time 1, nine of 12 cross-lagged associations across three models were statistically significant, with different patterns for females and males. There were reciprocal associations between bullying victimisation and mental health problems. Bullying victimisation was shown as an independent predictor of subsequent mental health problems; in turn, mental health problems preceded students' experience of becoming victims or bully-victims. Females with mental health problems were more likely to be victims; whereas similarly distressed males were vulnerable to both being bullied and being perpetrators. CONCLUSION: This study is the first of its kind in Vietnam and in the Southeast Asian region to examine reciprocal associations between bullying victimisation and mental health problems among adolescents. Anti-bullying intervention and prevention programs and school-based mental health promotion programs should be integrated and be sensitive to gender differences in order to maximise their impact.

In Vitro Production of Cartilage Tissue from Rabbit Bone Marrow-Derived Mesenchymal Stem Cells and Polycaprolactone Scaffold.

In vitro production of tissues or tissue engineering is a promising approach to produce artificial tissues for regenerative medicine. There are at least three important components of tissue engineering, including stem cells, scaffolds and growth factors. This study aimed to produce cartilage tissues in vitro from culture and chondrogenic differentiation of rabbit bone marrow-derived mesenchymal stem cells (BMMSCs), induced by chondrogenesis medium, on biodegradable polycaprolactone (PCL) scaffolds. BMMSCs were isolated from rabbit bone marrow according to the standard protocol. The adherence, proliferation and differentiation of BMMSCs on scaffolds were investigated using two scaffold systems: PCL scaffolds and collagen-coated PCL (PCL/col) scaffolds. The results showed that BMMSCs could attach and grow on both PCL and PCL/col scaffolds. However, the adhesion efficacy of BMMSCs on the PCL/col scaffolds was significantly better than on PCL scaffolds. Under induced conditions, BMMSCs on PLC/col scaffolds showed increased aggrecan accumulation and upregulated expression of chondrogenesis-associated genes (e.g. collagen type II, collagen type I, aggrecan and collagen type X) after 3, 7, 21 and 28 days of induction. These in vitro cartilage tissues could form mature chondrocyte-like cells after they were grafted into rabbits. The results suggest that use of BMMSCs in combination with polycaprolactone scaffolds and chondrogenesis medium can be a way to form in vitro cartilage tissue.

Analysis of Common ß-Thalassemia Mutations in North Vietnam.

Available and flexible choice of methods for screening and detecting ß-thalassemia (ß-thal) can promote control of thalassemia in developing countries. In this study, two methods, the amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and reverse dot-blot hybridization assays were developed to detect common ß-thal mutations in 244 thalassemia patients and 152 healthy people in North Vietnam. The most common mutation was codon 26 (G>A), also known as Hb E (HBB: c.79G>A), accounting for 26.4% of the total studied chromosomes, followed by codons 41/42 (-TCTT) (HBB: c.126_129delCTTT) and codon 17 (A>T) (HBB: c.c.52A>T), accounting for 19.4 and 16.4%, respectively. In addition, codon 95 (+A) (HBB: c.c.287_288insA) that is known as the Vietnamese mutation, accounted for 0.6%. Moreover, the heterozygous state of the four mutations was also found in healthy people, of which Hb E was again the most common mutation with a frequency 3.0%. The results of this study provide available methods and indicative data for preventive and control strategies concerning the genetic diagnosis of thalassemia.

Allogeneic Adipose-Derived Mesenchymal Stem Cell Transplantation Enhances the Expression of Angiogenic Factors in a Mouse Acute Hindlimb Ischemic Model.

Cell migration and molecular mechanisms during healing of damaged vascular or muscle tissues are emerging fields of interest worldwide. The study herein focuses on evaluating the role of allogenic adipose-derived mesenchymal stem cells (ADMSCs) in restoring damaged tissues. Using a hindlimb ischemic mouse model, ADMSC-mediated induction of cell migration and gene expression related to myocyte regeneration and angiogenesis were evaluated. ADMSCs were labeled with GFP (ADMSC-GFP). The proximal end of the femoral blood vessel of mice (over 6 months of age) are ligated at two positions then cut between the two ties. Hindlimb ischemic mice were randomly divided into two groups: Group I (n = 30) which was injected with PBS (100 µL) and Group II (n = 30) which was transplanted with ADMSC-GFP (106 cells/100 µL PBS) at the rectus femoris muscle. The migration of ADMSC-GFP in hindlimb was analyzed by UV-Vis system. The expression of genes related to angiogenesis and muscle tissue repair was quantified by real-time RT-PCR. The results showed that ADMSCs existed in the grafted hindlimb for 7 days. Grafted cells migrated to other damaged areas such as thigh and heel. In both groups the ischemic hindlimb showed an increased expression of several angiogenic genes, including Flt-1, Flk-1, and Ang-2. In particular, the expression of Ang-2 and myogenic-related gene MyoD was significantly increased in the ADMSC-treated group compared to the PBS-treated (control) group; the expression increased at day 28 compared to day 3. The other factors, such as VE-Cadherin, HGF, CD31, Myf5, and TGF-ß, were also more highly expressed in the ADMSC-treated group than in the control group. Thus, grafted ADMSCs were able to migrate to other areas in the injured hindlimb, persist for approximately 7 days, and have a significantly positive impact on stimulating expression of myogenic- and angiogenesis-related genes.

Extracellular vesicles of ETV2 transfected fibroblasts stimulate endothelial cells and improve neovascularization in a murine model of hindlimb ischemia.

Ischemia are common conditions related to lack of blood supply to tissues. Depending on the ischemic sites, ischemia can cause different diseases, such as hindlimb ischemia, heart infarction and stroke. This study aims to evaluate how extracellular vesicles (EVs) derived from ETV2 transfected fibroblasts affect endothelial cell proliferation and neovascularization in a murine model of hindlimb ischemia. Human fibroblasts were isolated and cultured under standard conditions and expanded to the 3th passage before use in experiments. Human fibroblasts were transduced with a viral vector containing the ETV2 gene. Transduced cells were selected by puromycin treatment. These cells were further cultured for collection of EVs, which were isolated from culture supernatant. Following co-culture with endothelial cells, EVs were evaluated for their effect on endothelial cell proliferation and were directly injected into ischemic tissues of a murine model of hindlimb ischemia. The results showed that EVs could induce endothelial cell proliferation in vitro and improved neovascularization in a murine model of hindlimb ischemia. Our results suggest that EVs derived from ETV2-transfected fibroblasts can be promising non-cellular products for the regeneration of blood vessels.

ETV-2 activated proliferation of endothelial cells and attenuated acute hindlimb ischemia in mice.

Ischemia is the reduction of blood flow to tissues by injury of blood vessels. Depending on the sites of tissues and grade of ischemia, ischemia can cause many serious complications. This study aimed to evaluate the effects of the E-twenty six (ETS) factor Ets variant 2 (ETV2) gene expression in angiogenesis and the effect of ETV2 gene therapy in a mouse model of hindlimb ischemia. The role of ETV2 on endothelial cell proliferation was evaluated in vitro. Knockdown of ETV2 expression was done using short hairpin RNA (shRNA) lentiviral viral particles. The ETV2 viral vector was injected into the skeletal muscles at the ligated and burned sites of the hindlimb and evaluated for its efficacy as a gene therapy modality for ischemia. Vascular regeneration in mice was indirectly evaluated by changes in mouse survival, necrotic grades of the leg, normal blood oxygen saturation level (SpO2), and blood flow by trypan blue injection assay. Preliminary data showed that ETV2 expression played a role in angiogenesis of endothelial cells. ETV2 overexpression could trigger and stimulate proliferation of skeletal endothelial cells. In vivo knockdown of ETV2 expression inhibited the auto-recovery of ischemic hindlimb, while overexpression of ETV2 helped to rescue leg loss and reduce necrosis, significantly improving angiogenesis in hindlimb ischemia. Our findings demonstrate that ETV2 gene therapy is a potentially effective modality for vascular regeneration.

Temporal patterns and predictors of bullying roles among adolescents in Vietnam: a school-based cohort study.

Although many cross-sectional studies have examined bullying experiences and correlated factors among adolescents in schools, relatively little is known about the extent to which bullying roles are stable or fluid over time. This short-term quantitative longitudinal study in Vietnam examined temporal patterns and predictors of bullying roles over an academic year. A total of 1424 middle and high school students aged 12-17 years completed two anonymous, self-administered questionnaires six months apart in 2014 and 2015. Young people were classified into different bullying roles as follow: not-involved (38.9%), victims only (24%), bullies only (6.6%), and bully-victims (40.4%) across the two times. About 60% of all surveyed students experienced bullying either as victim, bully, or bully-victim during the year. Of these students, nearly three in four indicated unstable bullying roles over time. Multivariate multinomial logistic regressions indicated factors ranging from individual (age, gender, and mental health) to family (social support, parental supervision and monitoring, witnessing parental violence, and conflict with siblings), school (perceived social support, teachers' attempt to stop bullying at school), and peers (social support, students' attempt to stop bullying at school) have significant associations with levels of bullying involvement. Implications for bullying prevention programs nationally and internationally are discussed.

Longitudinal associations between bullying and mental health among adolescents in Vietnam.

OBJECTIVES: This study measured bullying roles across an academic year and examined how change in bullying experiences is associated with symptoms of depression, psychological distress, and suicidal ideation among adolescents in Vietnam. METHODS: 1424 students in middle and high schools completed two self-administered questionnaires, six months apart in 2014-2015. RESULTS: Students who were victimised often and those who were classified as highly involved as both victims and bullies at one or both survey times showed significantly higher levels of depression, psychological distress, and suicidal ideation than other students. The mental health of adolescents who were involved in bullying as a victim or bully remained at low levels was generally similar to those not involved in any bullying. However, females who had stable but low level in victimisation or bully-victim status had worse mental health than males with stable-low-level exposure. CONCLUSION: This is the first longitudinal analysis of bullying among adolescents in Vietnam. Persistent and frequent bullying was strongly linked with poor mental health for males and females. A new observation is that Vietnamese girls appear to be more sensitive to low level but long-term bullying involvement than were boys.

Production of endothelial progenitor cells from skin fibroblasts by direct reprogramming for clinical usages.

Endothelial progenitor cells (EPCs) play an important role in angiogenesis. However, they exist in limited numbers in the human body. This study was aimed to produce EPCs, for autologous transplantation, using direct reprogramming of skin fibroblasts under GMP-compliant conditions. Fibroblasts were collected and cultured from the skin in DMEM/F12 medium supplemented with 5% activated platelet-rich plasma and 1% antibiotic-antimycotic solution. They were then transfected with mRNA ETV2 and incubated in culture medium under hypoxia (5% oxygen) for 14 d. Phenotype analysis of transfected cells confirmed that single-factor ETV2 transfection successfully reprogrammed dermal fibroblasts into functional EPCs. Our results showed that ETV2 mRNA combined with hypoxia can give rise to functional EPCs. The cells exhibited functional phenotypes similar to endothelial cells derived from umbilical cord vein; they expressed CD31 and VEGFR2, and formed capillary-like structures in vitro. Moreover, these EPCs could significantly improve hindlimb ischemia in mouse models. Although the direct conversion efficacy was low (3.12 ± 0.98%), altogether our study demonstrates that functional EPCs can be produced from fibroblasts and can be used in clinical applications.

Isolation of novel triple-reassortant swine H3N2 influenza viruses possessing the hemagglutinin and neuraminidase genes of a seasonal influenza virus in Vietnam in 2010.

Surveillance of swine influenza viruses (SIVs) in 31 pig farms in northern and southern parts of Vietnam was conducted. Six H3N2 influenza A viruses were isolated from a pig farm in southern Vietnam. They were novel genetic reassortants between a triple-reassortant SIV and a human seasonal H3N2 virus. Their hemagglutinin and neuraminidase genes were derived from a human virus circulating around 2004-2006 and the remaining genes from a triple-reassortant SIV that originated in North America. This is the first report describing the isolation of a novel triple-reassortant SIV in Vietnam.