Diffusion tensor imaging (DTI)can reflect the brain structure and development more quantitatively and intuitively than conventional magnetic resonance sequence by obtaining the diffusion properties of water molecules. In neonatal brain developmental research,DTI could be used to study the developmental regularities of white matter tracts and cerebral structure deformity.It can also help to explore the relationship between white matter microstructure and neurodevelopmental outcome.In the study of brain injury,including premature white matter injury,hypoxic ischemic encephalopathy,neonatal stroke,and so on,DTI can diagnose the brain microstructure injury precisely,evaluate the ef-fectiveness of interventions and predict the long -term neurodevelopmental outcome.DTI may have good prospect in re-search and clinical application on neonatal brain development and injury.

Interest temptation is a relatively hidden improper activity in medical human trials.Improper influence brought by interest temptation mainly displays allure in mind on subjects,which may lead them to make unreal promise.To avoid interest temptation and the undue influence,it needs to essentially distinguish interest temptation and interest sharing,apply different rules to different types of the subjects and strengthen the supervision function of institutional ethics committee.

BACKGROUND: Reports regarding adipose-derived stern cells (ADSCs) differentiation into dopaminergic (DN) neurons are few in addition, there is not experimental evidence of the effect of ADSCs on maintaining the survival of DN neurons.OBJECTIVE: To investigate the effect of glial cell-derived neurokophic factor (GDNF)-modified adipose-derived stem cells on survival of DN neurons under co-cultured condition.DESIGN, TIME AND SETrlNG: The in vitro cytology experiment was conducted at the Institute of Otolaryngology-Head and Neck Surgery and Key Laboratory of Zoonoses of Ministry of Education between March and December 2007.MATERIALS: Wistar rats with 3-weeks-old, or 14 days of pregnancy were provided by Norman Bethune College of Medicine, Jilin University.METHODS: The GDNF recombinant adenovirus was constructed by using pAdTrackCMV and pAdEasy-1 system. DN neurons were obtained from the rostral mesencaphalic tegmentum of Wistar rat embryos by using trypsin and collagenase method. ADSCs isolated from rat inguinal fat pads were digested with collagenase Ⅱ, cultured and passaged in vitro. When the cells reached 60% cenfluency at the 3rd passage, cells were transfectad with 1×109vp/mL of Ad-GDNF for 1 hour and then transferred into growth medium for another 24 hours, and GDNF level in cell supematant was detected by ELISA assay. Meanwhile, the co-cultured of ADSCs and DN neurons were carried out for following 7 days. With GFP-modified ADSCs was served as a control group.MAIN OUTCOME MEASURES: The effect of co-cultured condition on the survival of DN neurons, as well as the differentiation of GDNF-modified ADSCs was detected by immunofluorescence staining.RESULTS: GDNF appeared in ADSCs supematant at 24 hours after Ad-GDNF transfection and reached a peak at 72 hours.There was approximately 80% GFP-positive labeled in ADSCs. The tyrosinase hydroxylase staining results demonstrated that the rate of survival DN neurons were significantly increased than in DA neurons cultured alone, co-cultured group of GFP-modified ADSCs and GDNF-modified ADSCs groups (55%, 15%, 25%, P < 0.01). However, there were no co-expressing TH and GFP positive cells appeared at 7 days of co-culture, which indicated that the co-cultured condition was not available to ADSCs differentiation.CONCLUSION: The co-cultured of GDNF modified ADSCs and DN neurons can promote the survival and growth of cultured DN neurons, however, it can not induce ADSCs differentiate into DN neurons.

OBJECTIVE To investigate the effect of mono-2-ethylhexyl phthalate(MEHP) on proliferation of primary neural stem cells(NSCs)of rats and NE-4C cells of mice and on the migration of NE-4C cells and the mechanism. METHODS NE-4C or NSCs were treated with MEHP 1,10,100 and 1000 μmol · L-1 for 72 h,respectively. The cytotoxicity was estimated with the cell counting kit-8 (CCK-8). Cell proliferation was analyzed by EdU assay. The mRNA expression levels of the glucocorticoid receptor(GR),signal transducer and activator of transcription 3(Stat3)and sex determining region Y (SRY)-box 2(Sox2) were detected by qRT-PCR. The protein expression levels of total GR,GRβ, Sox2,Stat3 and p-Stat3 were measured by Western blotting. RESULTS Cell viability of NE-4C cells and NSCs at MEHP 1000μmol·L-1 was significantly decreased,which was 70.3%and 40.0%of the control group, respectively. EdU assay showed that MEHP 100 μmol · L-1 decreased NE-4C cells and NSCs by 74.8%and 12.0%(P<0.05)compared with control. The effect of MEHP on the cell migration of NE-4C was evidenced by the fact that the migration was obviously reduced to (63.4±2.0)%(P<0.05)after treatment with MEHP 100μmol · L-1 for 72 h. The mRNA expression levels associated with proliferation and migration in NE-4C of GR,Stat3 and Sox2 in MEHP 100 μmol · L-1 group were down-regulated to 49.8%,26.0% and 14.0%of control(P<0.05). At MEHP 100μmol · L-1,mRNA of GR, Stat3 and Sox2 in NSCs declined to 10.0%,14.0% and 15.3% of normal control. Western blotting results revealed that protein expressions of GR,GRβ,Sox2 and p-Stat3 were remarkably inhibited by MEHP 100 μmol · L-1 in that the relative expression of NE-4C was 0.92 ± 0.17,0.87 ± 0.35,0.81 ± 0.22 and 0.62 ± 0.24(P<0.05). The corresponding protein expression in NSCs was 0.82 ± 0.20,0.56 ± 0.12,0.84 ± 0.36 and 0.53 ± 0.20(P<0.05)when the cells were treated with MEHP 100μmol · L-1 for 72 h. CONCLUSION MEHP can inhibit the proliferation and migration of NE-4C cells and NSCs possibly by decreasing Stat3 and Sox2 that are mediated by GRβ.

Objective:To investigate the effect of placenta previa attached to cesarean scar for adverse pregnant outcomes in patients with or without placenta accreta spectrum disorders (PAS).Methods:The clinical information of patients with cesarean section history and placenta previa during the perioperative period at Peking University First Hospital from January 1st, 2015 to December 31st, 2020 were collected retrospectively. There were 53 cases without PAS and 172 cases with PAS, 153 cases with abnormally invasive placenta (containing placenta increta and placenta percreta) and 72 cases without PAS or with placenta accreta. The pregnant outcomes including rate of postpartum hemorrhage, transfusion, hysterectomy between the above groups were compared. Multivariate analysis was performed to study the factors significantly associated with PAS.Results:Pregnant women with PAS were at higher risk of adverse pregnant outcomes than those without PAS. Patients with PAS had higher incidences of hysterectomy [12.2% (21/172) vs 0(0/53); P=0.005], postpartum hemorrhage [60.5% (104/172) vs 5.7% (3/53); P<0.01] and blood transfusion [66.9% (115/172) vs 7.5% (4/53); P<0.01]. In the subgroup analysis stratified by the type of PAS, patients with abnormally invasive placenta were at higher risk of hysterectomy [13.7% (21/153) vs 0 (0/72); P<0.01], postpartum hemorrhage [66.7% (102/153) vs 6.9% (5/72); χ2 =70.873, P<0.01] and blood transfusion [74.5% (114/153) vs 6.9% (5/72); χ2 =90.869, P<0.01]. After multiple logistic regression, the type of creta had the positive relation with postpartum hemorrhage ( OR=27.622, 95% CI:9.873~77.280; P<0.01) and blood transfusion ( OR=36.912, 95% CI:13.239~102.922; P<0.01). There were no significant correlations between adverse pregnant outcomes and the type of placenta previa or the times of cesarean section (all P>0.01). Conclusions:Placenta previa attached to cesarean scar without PAS or with placenta accreta could not act as the factor of predicting adverse pregnant outcomes in clinic. Placenta previa attached to cesarean scar with placenta increta or placenta percreta could increase the risk of adverse pregnant outcomes.

As adult stem cells, human mesenchymal stem cells (hMSCs) have the potential for self-replication, renewal, and multidirection differentiation. Their unique biological function determines their wide clinical indications. Researchers can define the quality attributes of hMSCs according to clinical expectations. The quality study of hMSCs should consider microbiological safety, biological safety, cell biological properties, and biological effectiveness. Quality evaluation is a common physical, chemical, and biological evaluation method for hMSCs. Traditional product safety evaluation strategies cannot fully adapt to current technology and product usage characteristics. Researchers have developed new, effective evaluation methods based on current technology. In terms of product efficacy evaluation strategies, an efficacy evaluation system has been gradually established and standardized according to the intended clinical use and based on quality studies, which can enable researchers to evaluate hMSCs products more comprehensively at different stages and processes. In this paper, the progress of quality research and evaluation of human mesenchymal stem cells was reviewed to provide a reference for the utilization of stem cells in the field of regenerative medicine.

In 2023, nonalcoholic fatty liver disease was renamed metabolic dysfunction-associated steatotic liver disease by the American and European liver associations. This new nomenclature recognizes metabolic dysfunction as the central driver of the disease, and the diagnostic criteria now require the presence of hepatic steatosis plus at least one of five cardiometabolic risk factors. B-mode ultrasonography remains the most common and practical method for detecting hepatic steatosis, although newer ultrasound techniques based on attenuation, backscatter, and speed of sound have gained traction as tools to diagnose and quantify hepatic steatosis. Additionally, ultrasound elastography is increasingly used in routine clinical practice to assess liver fibrosis, diagnose cirrhosis, and identify clinically significant portal hypertension.

In 2023, nonalcoholic fatty liver disease was renamed metabolic dysfunction-associated steatotic liver disease by the American and European liver associations. This new nomenclature recognizes metabolic dysfunction as the central driver of the disease, and the diagnostic criteria now require the presence of hepatic steatosis plus at least one of five cardiometabolic risk factors. B-mode ultrasonography remains the most common and practical method for detecting hepatic steatosis, although newer ultrasound techniques based on attenuation, backscatter, and speed of sound have gained traction as tools to diagnose and quantify hepatic steatosis. Additionally, ultrasound elastography is increasingly used in routine clinical practice to assess liver fibrosis, diagnose cirrhosis, and identify clinically significant portal hypertension.

In 2023, nonalcoholic fatty liver disease was renamed metabolic dysfunction-associated steatotic liver disease by the American and European liver associations. This new nomenclature recognizes metabolic dysfunction as the central driver of the disease, and the diagnostic criteria now require the presence of hepatic steatosis plus at least one of five cardiometabolic risk factors. B-mode ultrasonography remains the most common and practical method for detecting hepatic steatosis, although newer ultrasound techniques based on attenuation, backscatter, and speed of sound have gained traction as tools to diagnose and quantify hepatic steatosis. Additionally, ultrasound elastography is increasingly used in routine clinical practice to assess liver fibrosis, diagnose cirrhosis, and identify clinically significant portal hypertension.

In 2023, nonalcoholic fatty liver disease was renamed metabolic dysfunction-associated steatotic liver disease by the American and European liver associations. This new nomenclature recognizes metabolic dysfunction as the central driver of the disease, and the diagnostic criteria now require the presence of hepatic steatosis plus at least one of five cardiometabolic risk factors. B-mode ultrasonography remains the most common and practical method for detecting hepatic steatosis, although newer ultrasound techniques based on attenuation, backscatter, and speed of sound have gained traction as tools to diagnose and quantify hepatic steatosis. Additionally, ultrasound elastography is increasingly used in routine clinical practice to assess liver fibrosis, diagnose cirrhosis, and identify clinically significant portal hypertension.