BACKGROUND: Current replacement procedures for stenosis or occluded arteries using prosthetic grafts have serious limitations in clinical applications, particularly, endothelialization of the luminal surface is a long-standing unresolved problem.METHOD: We produced a cell-based hybrid vascular graft using a bioink engulfing adipose-derived mesenchymal stromal cells (ADSCs) and a 3D bioprinting process lining the ADSCs on the luminal surface of GORE-Tex grafts. The hybrid graft was implanted as an interposition conduit to replace a 3-cm-long segment of the infrarenal abdominal aorta in Rhesus monkeys. RESULTS: Complete endothelium layer and smooth muscle layer were fully developed within 21 days post-implantation, along with normalized collagen deposition and crosslinking in the regenerated vasculature in all monkeys. The regenerated blood vessels showed normal functionality for the longest observation of more than 1650 days. The same procedure was also conducted in miniature pigs for the interposition replacement of a 10-cm-long right iliac artery and showed the same long-term effective and safe outcome. CONCLUSION This cell-based vascular graft is ready to undergo clinical trials for human patients.

Alzheimer's disease (AD) is one of the major diseases that harmful to healthy elderly, and mild cognitive impairment (MCI) is the early clinical stage of AD. There is a lag in the clinical diagnosis of both diseases. An objective and reliable auxiliary diagnostic method is urgently needed to provide early diagnosis and differential indicators for AD and MCI, to predict the probability of individuals suffering from AD and MCI transforming into AD, and to reduce the overall incidence of AD and reduce the huge medical and economic burden for the country and society. Event-related potential is widely used in AD and MCI, and the resolution at the millisecond level can truly reflect the time course of cognitive processing and the degree of impairment of cognitive function in patients. In this study, we investigated the differences in the amplitude and latency of ERP components in healthy elderly, MCI and AD patients, and the correlation between ERP components and cognitive impairment. Early N170 and P200 showed high sensitivity and specificity in differentiating MCI from healthy elderly or MCI from AD. The late perception-related ERPs also showed high sensitivity and specificity in differentiating healthy elderly from MCI/AD. The differences in ERPs between MCI and AD may be related to the etiology, the degree of disease progression and the site of brain damage. The specific brain mechanism still need to be further explored and will be the focus of future research. With the progress of the research, the relationship between the specific ERP manifestations and the mechanism of brain injury as well as the impairment of cognitive function will be more clear. It is believed that the application of ERP in clinical will bring more benefits to AD and its early clinical MCI.

COVID-19 is caused by the 2019 novel coronavirus, which is characterized by hidden onset, long incubation period, and high contagion. The study found that the COVID-19 not only attacks the respiratory system, but also affects other systems such as the heart, kidney, and digestive tract, and could be combined with multiple system diseases such as acute cerebrovascular disease. If doctors, especially non-infective or respiratory doctors, do not pay great attention to the patient when they are receiving patients, and take good care of them, they may easily cause their own infection. This article summarizes the case of a concealed onset COVID-19 patient with cerebral infarction, which caused a medical staff infection after intravenous thrombolytic therapy, explores its clinical characteristics, treatment process and analyzes its prevention and control links to help the epidemic situation. In the prevention and control, the first-time doctor should pay attention to identification, reduce missed diagnosis, and scientific investigation to reduce occupational infection.

Objective:To explore the effects of cartoon game-style health education combined with group counseling in children with refractory Tourette syndrome (TS) .Methods:Totally 93 children with refractory TS admitted in The First Affiliated Hospital of Zhengzhou University from February 2018 to May 2019 were selected and divided into a combined group, an observation group and a control group, with 31 patients in each group. Patients in the control group received routine pediatric care; patients in the observation group received group counseling on the basis of the control group; patients in the combined group received cartoon game-style health education on the basis of the observation group. Swanson Nolan and Pelham (SNAP-IV) , Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) , Piers-Harris Child Self-Consciousness Scale (PHCCS) , Chinese version- Wechsler Intelligence Scale for Children (C-WISC) , Yale Global Tic Severity Scale (YGTSS) and Inventory of Subjective Life Quality (ISLQ) were used to evaluate the effects of the three groups before and after intervention.Results:After 4 weeks of intervention, the mental disorders, consciousness, clinical symptoms and quality of life were improved in the three groups of children. The SNAP-IV, Y-BOCS, YGTSS and ISLQ scores of the combined group were (21.29±5.15) , (12.93±3.53) , (25.47±4.09) and (48.77±8.81) , respectively, lower than those of the control group and the observation group, and the differences were statistically significant ( P<0.05) . The PHCCS and C-WISC scores of the combined group were (54.07±6.48) and (97.23±5.94) , higher than those of the observation group and the control group, and the differences were statistically significant ( P<0.05) . Conclusions:Cartoon game-style health education combined with group counseling can effectively improve the clinical symptoms of children with refractory TS, mitigate their emotional and psychological disorders, and improve their quality of life.

BACKGROUND:Along with the widespread application of biodegradable materials in the field of medicine and the in-depth research of biomechanics,the drawbacks of traditional medical metal materials are increasingly appearing.In recent years,researchers at home and abroad focus on biodegradable materials that are represented by high molecular polymer to seek new breakthroughs in the field of spinal instability.OBJECTIVE:To investigate biomechanical changes of polylactic acid-polyglycolic acid (PLGA) lumbar interbody fusion cage in the body and discusses its feasibility for treating segmental instability of the spine.METHODS:Forty-two healthy pigs (9 months old) were randomly divided into two groups (n=21),and L4/5 intervertebral disc nucleus pulposus was removed in all animals.In experimental group,PLGA lumbar interbody fusion cage filled with broken bone was implanted;and in control group,autologous bone was implanted.X-ray was performed to observe the fusion of operation segments at 4,12 and 72 weeks postoperatively.Feasibility of fibrous fusion was measured by biomechanical test.Histologically,bone graft fusion at the surgical site and material degradation were detected.RESULTS AND CONCLUSION:(1) Imaging examination:Bone graft fusion in two groups was not visible at 4 weeks after operation.Evidence of increasing fusion was found in the experimental group at 12 weeks after operation;a visible part of the bone bridge was found in the control group,in which there was one case of fusion.Degradation of the fusion cage with one case of fusion in experimental group was found after 72 weeks after operation,and two cases of fusion in the control group.(2) Biomechanical test:There was no difference in the spinal range of motion between the two groups in different states at 4 weeks after operation (P ＞ 0.05).The spinal range values of motion at most of the states at 72 weeks after operation were significantly lower than those at 4 weeks after operation.(3) Cell histology observation:With the passage of time,the materials in the experimental group degraded gradually;new bone grew slowly and then fast,with bone fusion step by step.Fusion results were similar in the two groups.Our experimental findings indicate that the PLGA lumbar fusion cage has good biocompatibility.In addition to the individual state (left flexion),the mechanical properties of the fusion cage are similar to that of autogenous bone,and the fusion cage enables the segmental reconstruction of the pig spine to the maximum extent.

Objective:To determine the molecular role of DNA methyltransferase (DNMT) in kidney tumorigenesis. Methods:Tissue samples consisted of 15 cancer tissues and 15 matched adjacent tissues from clear cell renal cell carcinoma (ccRCC) patients who had undergone nephrectomy in 2012 at the First Affiliated Hospital of Baotou Medical College, Science and Technology University of Inner Mongolia were collected. Real-time PCR, Western blot, combined bisulfite restriction analysis (COBRA) and methylation specific PCR were used in this study. Real-time PCR was used to examine the mRNA expression levels of DNMT. The global methylation level, DNA methylation level, and the expression of the antioncogene RASSF1A in ccRCC tissues were concurrently detected. Results:Both mRNA and protein levels of DNMT3B4, a splice variant of DNMT3B, were elevated in renal cell carcinoma tissue compared with those in con-troll tissue. Additionally, Alu was hypomethylated in ccRCC tissue (0.106±0.04) compared with control tissue (0.115±0.03) (P<0.05). Fur-thermore, the methylation of the promoter for RASSF1A, a tumor-suppressor gene, moderately increased in renal cell carcinoma tis-sue. By contrast, RASF1A expression decreased. Conclusion:DNMT3B4 overexpression may play an important role in human kidney tu-morigenesis via chromosomal instability and the decreased expression of RASSF1A.

Objective To explore the difference of social support,self-esteem and marital quality between urban and rural areas and discuss the impact on each other.Methods Chinese marital quality questionnaire,selfesteem scale (SES) and social support rating scale were used to test 386 urban and rural married residents.Results ①The results of descriptive statistics showed that marriage quality,social support and self-esteem of urban and rural residents were (318.46±37.41),(42.44±5.84) and (30.65 ± 3.95) respectively.②There was no significant difference among social support,self-esteem and marital quality in different gender(t =0.41,-0.16,0.03,P＞ 0.05),but had significant difference between urban and rural areas(t=2.83,3.91,5.24,P＜0.01).There were significant differences between social support and marital quality in different age structures(t=5.22,3.85,P＜0.05).There were significant differences between social support and self-esteem in different educational level (t =3.48,4.16,P＜0.01).③Social support,subjective support,objective support and marital quality had positive correlation (r=0.114～0.394,P＜0.05).The degree and character compatibility,communication between couples,resolve conflicts are positively related to support (r=0.308～ 0.476,P＜0.01).④Stepwise multiple regression analysis and structural equation modeling analysis showed that self-esteem played partial intermediary role between social support and marital quality(37.7％),which could explain 26.8％ of marital quality.The social suptort and self-esteem could better predict marital quality.Conclusion The higher social support and self-esteem are,the higher marital quality is.Social support can directly affect the marital quality and indirectly affect marital quality through self-esteem.

Objective To study the effects of AuNPs@PEG-AS1411 nanoparticles on radiosensitization of human uterine cervix cancer HeLa cells.Methods AuNPs were synthesized by citrate reduction method and then functioned with PEG and PEG-AS1411, respectively.CCK-8 assay and colon forming assay were used to detect the acute and chronic toxicity effects of AuNPs on HeLa cells, respectively.At the same time, clonogenic survival assay was applied to measure the cell survival rate of HeLa cells after exposure to AuNPs@PEG and AuNPs@PEG-AS1411 combined with X-ray radiation.The intracellular uptake of AuNPs@PEG and AuNPs@PEG-AS1411 in HeLa cells were detected by ICP-MS.Results The CCK-8 assay showed that AuNPs@PEG and AuNPs@PEG-AS1411 were not toxical on HeLa cells(P ＞0.05).But the clonogenic survival assay showed that AuNPs@PEG and AuNPs@PEG-AS1411 had toxicity on HeLa cells significantly after 10 d(t =4.38-11.60, P ＜ 0.05).AuNPs functioned with AS1411 could increase the cellular uptake of AuNPs.AuNPs@PEG and AuNPs@PEG-AS1411 both had significant radiosensitive effect on HeLa cells (F =7.90,48.23, P ＜ 0.05).The values of SERDo for AuNPs@PEG and AuNPs@PEG-AS1411 were 1.12 and 1.20, respectively, when the concentration of Au was 10 mg/L.Conclusions AuNPs@PEG and AuNPs@PEG-AS1411 could cause chronic toxicity on HeLa cells instead of acute effect.PEGylated AuNPs functioned with AS1411 could enhance the radiosensitivity of HeLa cells in vitro.

OBJECTIVEThe objective of this study was to investigate the aspiratory resistance, filtration penetration and their influence factors of N95 filtering-facepiece respirators used widely in China.

METHODSThe total of 6 brands and 21 models of N95 filtering-facepiece respirators which are certified and big sales on the market. The aspiratory resistance and filtration efficiency filter penetration were measured while air pump ran from 10 L/min to 100 L/min using differential pressure gauge and the PortaCount, respectively.

RESULTSThe filtration penetrations for 2 of the 21 models were lower than 95%, and the qualified rate for all models was 90.47%. The filtration penetrations gradually decreased when ventilation flow of air pump increased. The negative correlation was observed between filtration penetration and ventilation flow (r(2) = 0.711, P < 0.05). The resistances of all 21 models of N95 respirators met the requirements of the national standard. The aspiratory resistance started to elevate with the increasing of ventilation flow, and a positive correlation between both (r(2) = 0.878, P < 0.05). Significant differences of filtration penetration and aspiratory resistance were observed among between different brands (P < 0.05) although no differences of filtration penetration existed among different models of one brand (P > 0.05). But the differences of the aspiratory resistance among different models of one brand were statistically significant (P < 0.05).

CONCLUSIONThe aspiratory resistances of all N95 filtering-facepiece respirators used in this study met the requirements of the national standard. And the qualified ratio of filtration penetration of all models was higher than 90%. The influencing factors of aspiratory resistance included materials, size and ventilation flow. And influencing factors for filtration penetration were materials and ventilation flow.

Air Pollutants, Occupational ; China ; Equipment Design ; Filtration ; instrumentation ; Masks ; standards ; Materials Testing ; Respiratory Protective Devices ; standards

Background The clinical effectiveness of soft corneal contact lens for correction of myopia has been confirmed.Theoretically,aspherical soft hydrophilic corneal contact lens has better visual qualify for myopic eyes,and the lenses have been applied widely.But abnormal tear film,even many cornea and conjuctiva diseases caused by soft contact lens have been reported,so the effectiveness and safety of aspherical soft hydrophilic corneal contact lens are worth concerning.Objective This clinical trail was to compare the effectiveness and safety between aspherical and NUV soft hydrophilic contact lens for myopic eyes.Methods A randomized,double-blind and controlled clinical study was performed under the approval of Ethic Committee of Qingdao Municipal Hospital and informed consent of each patient.One hundred and forty eyes of 70 myopic patients were enrolled in QingdaoMunicipal Hospital from July to October,2012.The subjects were randomized into the trial group and control group using random number table.Aspherical soft hydrophilic contact lenses were worn in the trial group and NUV soft hydrophilic contact lenses were worn in the control group.The characteristics of the lens surface,outcomes and the eye number in different scores of ocular signs and symptoms were assessed before and 15 minutes,1 week,2 weeks and 1 month after wearing lenses.Results The sores of humidity of anterior surface,the sediment in anterior and posterior surface are 0 in both lenses in various time points after wearing.The corrected visual acuity of all the subjects were ≥ 1.0.The eye number of 2-3 scores in various ocular signs was 0 in both groups,but the eye number of 1 score in palpebral conjunctival congestion and limbus congestion were more in the trail group than those in the control group in different time points (all at P＜0.05).There were significant differences in corneal fluorescine staining between the groups in different time points (all at P＞0.05).There was no eye for 2-3 scores of eye symptoms in both groups.The eye number for 1 score in foreign body sensation increased in the target-trail group compared to the control group at various time points (P =0.002,0.006,0.005,0.005).However,there was no statistically significant differences in the eye number for 1 score in visual clearness and stability between the two groups at the follow-up duration (all at P＞ 0.05).Conclusions Aspherical soft hydrophilic corneal contact lens has good outcomes in corrected visual acuity for myopia like NUV soft hydrophilic contact lens,but the wearing of aspherical soft hydrophilic corneal contact lens induces more ocular discomfortableness.