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1.
Neural Regen Res ; 16(2): 345-349, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32859795

RESUMO

Methyl-CpG-binding protein 2 (MeCP2) is a well-known transcription repressor, and mutations in MECP2 cause serious neurological disorders. Many studies have suggested that MeCP2 is involved in neural maturation only, and have not reported its role in neural stem cell differentiation. In the present study, we investigated this possible role of MeCP2 in neural stem cells. We used two different differentiation methods to explore how MeCP2 influences neural stem cell differentiation. When we transfected MeCP2-overexpressing lentivirus into neural stem cells, astrocytic differentiation was impaired. This impaired astrocytic differentiation occurred even in conditions of 20% fetal bovine serum, which favored astrocytic differentiation. In addition, miR-132 had the largest expression change after differentiation among several central nervous system related miRNAs. A luciferase assay confirmed that miR-132 directly targeted MeCP2, and that miR-132 was able to reduce MeCP2 expression at both the RNA and protein levels. The upregulation of miR-132 by miRNA mimics promoted astrocytic differentiation, which was fully recovered by MeCP2 overexpression. These results indicate that miR-132 regulates cell lineage differentiation by reducing MeCP2. The study was approved by the Ethics Committee of Shanghai Tenth People's Hospital of TongJi University, China (approval No. SHDSYY-2018-4748) on March 10, 2018.

2.
J Recept Signal Transduct Res ; : 1-8, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33043765

RESUMO

OBJECTIVE: Isoflurane is an extensively used inhalational anesthesia, and its carcinogenic or anti-cancerous effect has been identified recently. However, the specific role of isoflurane in cervical cancer remains unclear. AIM: This study aimed to investigate the function of isoflurane in cervical cancer as well as the underlying mechanism. METHODS: After isoflurane treatment, HeLa cell viability, percentage of apoptotic cells, expression of active caspase-3/9 were examined by CCK-8 assay, Annexin V-FITC/PI double staining, and Western blot analysis, respectively. ROS generation, ratio of NAD+/NADH, and ATP level after isoflurane stimulation were determined using commercial assay kits. Afterwards, activation of AMPK and autophagy was assessed through Western blot analysis and immunofluorescence. Whether AMPK mediated the isoflurane-induced apoptosis and autophagy was explored by adding an AMPK inhibitor (Compound C). The in vivo function of isoflurane was finally investigated on a HeLa cell xenograft model. RESULTS: Isoflurane inhibited cell viability and induced apoptosis evidenced by upregulation of active caspase-3/9 in HeLa cells. Oxidative stress was triggered by isoflurane, as isoflurane elevated ROS level, and lowered ratio of NAD+/NADH and ATP level. Further results showed isoflurane activated the AMPK/mTOR pathway and induced autophagy. In addition, inhibition of AMPK led to ameliorated effects of isoflurane on apoptosis and autophagy. In vivo experiments proved isoflurane could repress tumorigenesis, activate AMPK, and induce autophagy in Xenograft mouse. CONCLUSIONS: Isoflurane activated AMPK to inhibit proliferation and promote apoptosis and autophagy both in vitro and in vivo.

3.
Clin Infect Dis ; 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33044509

RESUMO

BACKGROUND: Shigella is a leading cause of childhood diarrhea and target for vaccine development. Microbiologic and clinical case definitions are needed for pediatric field vaccine efficacy trials. METHODS: We compared characteristics of moderate to severe diarrhea (MSD) cases in the Global Enteric Multicenter Study (GEMS) between children with culture positive Shigella to those with culture-negative, qPCR-attributable Shigella (defined by an ipaH gene cycle threshold <27.9). Among Shigella MSD cases, we determined risk factors for death and derived a clinical severity score. RESULTS: Compared to culture-positive Shigella MSD cases (n=745), culture-negative/qPCR-attributable Shigella cases (n=852) were more likely to be under 12 months, stunted, have a longer duration of diarrhea, and less likely to have high stool frequency or a fever. There was no difference in dehydration, hospitalization, or severe classification from a modified Vesikari score. Twenty-two (1.8%) Shigella MSD cases died within the 14-days after presentation to health facilities, and 59.1% of these deaths were in culture-negative cases. Age < 12 months, diarrhea duration prior to presentation, vomiting, stunting, wasting, and hospitalization were associated with mortality. A model-derived score assigned points for dehydration, hospital admission, and longer diarrhea duration but was not significantly better at predicting 14-day mortality than a modified Vesikari score. CONCLUSIONS: A composite severity score consistent with severe disease or dysentery may be a pragmatic clinical endpoint for severe shigellosis in vaccine trials. Reliance on culture for microbiologic confirmation may miss a substantial number of Shigella cases but is currently required to measure serotype specific immunity.

4.
Metab Brain Dis ; 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33044640

RESUMO

Ischemic postconditioning (PostC) conventionally refers to a series of brief blood vessel occlusions and reperfusions, which can induce an endogenous neuroprotective effect and reduce cerebral ischemia/reperfusion (I/R) injury. Depending on the site of adaptive ischemic intervention, PostC can be classified as in situ ischemic postconditioning (ISPostC) and remote ischemic postconditioning (RIPostC). Many studies have shown that ISPostC and RIPostC can reduce cerebral IS injury through protective mechanisms that increase cerebral blood flow after reperfusion, decrease antioxidant stress and anti-neuronal apoptosis, reduce brain edema, and regulate autophagy as well as Akt, MAPK, PKC, and KATP channel cell signaling pathways. However, few studies have compared the intervention methods, protective mechanisms, and cell signaling pathways of ISPostC and RIPostC interventions. Thus, in this article, we compare the history, common intervention methods, neuroprotective mechanisms, and cell signaling pathways of ISPostC and RIPostC.

5.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(5): 409-414, 2020 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-33047563

RESUMO

We use a dense and fully connected convolutional network with good feature learning in small samples, to automatically pre-deline CTV of cervical cancer patients based on CT images and evaluate the effect. The CT data of stage IB and IIA postoperative cervical cancer with similar delineation scope were selected to be used to evaluate the pre-sketching accuracy from three aspects:sketching similarity, sketching offset and sketching volume difference. It has been proved that the 8 most representative parameters are superior to those with single network and reported internationally before. Dense V-Net can accurately predict CTV pre-delineation of cervical cancer patients, which can be used clinically after simple modification by doctors.

6.
PLoS Negl Trop Dis ; 14(10): e0008570, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: covidwho-841536

RESUMO

Little is known about the SARS-CoV-2 contamination of environmental surfaces and air in non-health care settings among COVID-19 cases. We explored the SARS-CoV-2 contamination of environmental surfaces and air by collecting air and swabbing environmental surfaces among 39 COVID-19 cases in Guangzhou, China. The specimens were tested on RT-PCR. The information collected for COVID-19 cases included basic demographic, clinical severity, symptoms at onset, radiological testing, laboratory testing and hospital admission. A total of 641 environmental surfaces and air specimens were collected among 39 COVID-19 cases before disinfection. Among them, 20 specimens (20/641, 3.1%) were tested positive from 9 COVID-19 cases (9/39, 23.1%), with 5 (5/101, 5.0%) positive specimens from 3 asymptomatic cases, 5 (5/220, 2.3%) from 3 mild cases, and 10 (10/374, 2.7%) from 3 moderate cases. All positive specimens were collected within 3 days after diagnosis, and 10 (10/42, 23.8%) were found in toilet (5 on toilet bowl, 4 on sink/faucet/shower, 1 on floor drain), 4 (4/21, 19.0%) in anteroom (2 on water dispenser/cup/bottle, 1 on chair/table, 1 on TV remote), 1 (1/8, 12.5%) in kitchen (1 on dining-table), 1 (1/18, 5.6%) in bedroom (1 on bed/sheet pillow/bedside table), 1 (1/5, 20.0%) in car (1 on steering wheel/seat/handlebar) and 3 (3/20, 21.4%) on door knobs. Air specimens in room (0/10, 0.0%) and car (0/1, 0.0%) were all negative. SARS-CoV-2 was found on environmental surfaces especially in toilet, and may survive for several days. We provided evidence of potential for SARS-CoV-2 transmission through contamination of environmental surfaces.

7.
Materials (Basel) ; 13(20)2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33081179

RESUMO

As a representative of the third generation of advanced high strength steel, the quenching and partitioning steel has excellent potential in automobile manufacturing. The characterization and analysis of the mechanical properties and microstructure of the quenching and partitioning steel during deformation is an effective way to explore the microstructure evolution and transformation-induced plasticity effects of complex phase steels. The relationship between the microstructure morphology and mechanical properties of a 1180 MPa-grade quenching and partitioning steel was investigated through interrupted uniaxial tensile tests plus quasi-situ electron backscatter diffraction measurements. A mixture of ferrite, martensite, and retained austenite was observed in the microstructure. It was found that the volume fraction of global retained austenite decreased linearly with the increase of displacement (0 mm-1.05 mm). The evolution of the retained austenite with typical crystal direction ranges with deformation was characterized. Results show that the orientation (111) and (311) account for the highest proportion of retained austenite grains in the undeformed sample and the mechanical stability of the (311) retained austenite grains is the best. Moreover, the retained austenite grains rotated significantly in the early stage of the specimen deformation process (around yielding), and the work hardening of the specimen was weak at this stage, simultaneously.

8.
J Exp Clin Cancer Res ; 39(1): 220, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33081806

RESUMO

An amendment to this paper has been published and can be accessed via the original article.

9.
World J Clin Cases ; 8(19): 4416-4430, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33083401

RESUMO

BACKGROUND: Chronic pancreatitis is associated with pancreatic cancer (PC), although the relationship between acute pancreatitis (AP) and the risk of PC remains unclear due to inconsistent and contradictory results. AIM: To conduct a meta-analysis of retrospective and prospective studies to explore the association between AP and PC risk. METHODS: We first searched original articles on the association of AP with PC using PubMed, Web of Science, Cochrane, and EMBASE databases. Then we calculated the combined overall effect estimates (EEs) between AP and PC risk at a 95% confidence interval (CI) deploying a random-effects model, and assessed heterogeneity using the I 2 test. The combined relative risk with 95%CI was performed to examine the relationship between AP and PC. Publication bias and subgroup analyses were also conducted. Furthermore, we performed sensitivity analysis to explain this heterogeneity. RESULTS: Eleven studies were eligible for inclusion standards in this meta-analysis, resulting in pooled EEs of 2.07 (95%CI: 1.36-2.78) for AP and PC risk. Additionally, five prospective cohort studies reported 103961 patients in the AP group, relative to 1442158 subjects in the control group, with a pooled relative risk of 7.81 (95%CI: 5.00-12.19). We also performed subgroup analyses using different follow-up times and type of research methods (case-control or cohort). Results from analyses of different follow-up times revealed the following pooled effect values: 1-year lag period (EEs = 23.47, 95%CI: 3.26-43.68), 2-year lag period (EEs = 9.82, 95%CI: 3.01-16.64), 5-year lag period (EEs = 2.47, 95%CI: 1.93-3.02), 10-year lag period (EEs = 1.69, 95%CI: 1.26-2.11), and > 10-year lag period (EEs = 1.17, 95%CI: 0.78-1.57). With regards to the methods, the case-control studies recorded EEs = 3.03 (95%CI: -1.02 to 7.08), whereas cohort studies had EEs = 2.09 (95%CI: 1.22-2.97) pooled effect values. CONCLUSION: Overall, our findings indicated an association between AP and PC risk. Based on subgroup analyses, AP is unlikely to be a causal factor for PC.

10.
World J Clin Cases ; 8(19): 4676-4680, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33083433

RESUMO

BACKGROUND: The common treatment for hydrocephalus is insertion of a ventriculoperitoneal shunt. Shunt tube displacement is one of the common complications. Most shunt tube displacements occur in children and has a reportedly lower incidence in adults. CASE SUMMARY: This study reports an adult patient (male, 56 years) who suffered from intracranial aneurysm and subarachnoid hemorrhage and underwent aneurysm clipping following hospitalization. One month post onset of the disease, the patient underwent ventriculoperitoneal shunt due to hydrocephalus. The peritoneal end of the shunt tube was displaced in the peritoneal cavity 9 years after the aneurysm clipping. The peritoneal end of the shunt tube was removed and ventriculoperitoneal shunt was re-performed after anti-inflammatory treatment. CONCLUSION: Shunt tube displacement has a low incidence in adults. In order to avoid shunt tube displacement, there is a need to summarize its causative factors and practice personalized medicine.

11.
Zootaxa ; 4786(1): zootaxa.4786.1.2, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-33056494

RESUMO

The species of Prosoponoides Millidge Russell-Smith, 1992 from China are studied, including one new species, Prosoponoides youyiensis Liu Chen n. sp., and two known species, Prosoponoides hamatum Millidge Russell-Smith, 1992 and Prosoponoides sinense (Chen, 1991). Morphological descriptions and illustrations of P. hamatum and P. youyiensis Liu Chen n. sp. are given, and digital photos of P. sinense are provided.

12.
PLoS Genet ; 16(10): e1009068, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33057331

RESUMO

Diphthamide is a unique post-translationally modified histidine residue (His715 in all mammals) found only in eukaryotic elongation factor-2 (eEF-2). The biosynthesis of diphthamide represents one of the most complex modifications, executed by protein factors conserved from yeast to humans. Diphthamide is not only essential for normal physiology (such as ensuring fidelity of mRNA translation), but is also exploited by bacterial ADP-ribosylating toxins (e.g., diphtheria toxin) as their molecular target in pathogenesis. Taking advantage of the observation that cells defective in diphthamide biosynthesis are resistant to ADP-ribosylating toxins, in the past four decades, seven essential genes (Dph1 to Dph7) have been identified for diphthamide biosynthesis. These technically unsaturated screens raise the question as to whether additional genes are required for diphthamide biosynthesis. In this study, we performed two independent, saturating, genome-wide CRISPR knockout screens in human cells. These screens identified all previously known Dph genes, as well as further identifying the BTB/POZ domain-containing transcription factor Miz1. We found that Miz1 is absolutely required for diphthamide biosynthesis via its role in the transcriptional regulation of Dph1 expression. Mechanistically, Miz1 binds to the Dph1 proximal promoter via an evolutionarily conserved consensus binding site to activate Dph1 transcription. Therefore, this work demonstrates that Dph1-7, along with the newly identified Miz1 transcription factor, are likely to represent the essential protein factors required for diphthamide modification on eEF2.

13.
Artigo em Inglês | MEDLINE | ID: mdl-33057677

RESUMO

OBJECTIVES: This study was performed to assess the association between the dissection length-to-descending thoraco-abdominal aorta length ratio (LLR) and abdominal aortic enlargement (AAE) (≥20% increase in total abdominal aortic volume) after thoracic endovascular aortic repair (TEVAR) in patients with type B aortic dissection. METHODS: We retrospectively analysed data from 184 consecutive patients with type B aortic dissection who underwent TEVAR from January 2011 to December 2016 at 4 hospitals as part of the Registry Of type B aortic dissection with Utility of STent graft study. Preoperative and postoperative computed tomography angiography images were reviewed to assess the LLR and AAE. Patients were stratified into tertiles according to the pre-TEVAR LLR: 0.7 to <1.0 (n = 61), 1.0 to <1.2 (n = 61) and 1.2 to <1.6 (n = 62). The thoracic and abdominal aorta were divided by the celiac trunk. The cumulative incidence of AAE was estimated using the Kaplan-Meier method. A multivariable Cox proportional hazards model was used to assess the independent association between the preoperative LLR and the post-TEVAR risk of AAE. The nonlinear relationship between the LLR and the risk of post-TEVAR AAE was fitted by the restricted cubic smoothing spline, and the inflection point on the fitting curve was determined using a piecewise linear regression model. RESULTS: Baseline demographics, clinical features, preoperative anatomic characteristics and implanted devices were similarly distributed among the pre-TEVAR LLR tertile groups. At 24 months post-TEVAR, the estimated cumulative incidence of AAE significantly differed (P < 0.01) by LLR tertile group: 0.10 [95% confidence interval (CI) 0.00-0.21], 0.65 (95% CI 0.45-0.78) and 0.67 (95% CI 0.40-0.82), respectively. The pre-TEVAR LLR was an independent predictor of post-TEVAR AAE [hazard ratio (per unit increase) 1.03, 95% CI 1.01-1.04] following a nonlinear relationship with an inflection point at LLR = 1.0. CONCLUSIONS: The risk of post-TEVAR AAE is highest when the length of the dissection is greater than or equal to the length of the descending aorta (LLR ≥ 1.0).

14.
Head Neck ; 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33058368

RESUMO

BACKGROUND: To assess long-term donor site morbidity after radial forearm free (RFF) flap harvesting. METHODS: Enrolled patients were asked to complete the Disability of the Arm, Shoulder, and Hand (DASH) questionnaire and undergo wrist motion and hand strength examinations at different time points. The data were prospectively collected and retrospectively analyzed. RESULTS: The postoperative DASH score did not return to normal until 24 months after the operation. The mean postoperative wrist motion degree of flexion was significantly decreased compared to the preoperative level and returned to normal at 12 months after the operation. Similar trends were noted regarding extension, radial abduction, and ulnar abduction. The mean postoperative grip strength was significantly decreased compared to the preoperative level and remained dysfunctional at 24 months after the operation. A similar trend was also noted with regard to tip pinch and key pinch. CONCLUSION: The long-term negative effect on hand strength is sustained.

15.
Med Biol Eng Comput ; 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33064234

RESUMO

Exposure to low-frequency vibration is harmful to human lumbar health. However, the dynamic mechanical properties of lumbar spines with varying degrees of degeneration during time-dependent vibration remain incompletely understood. In this study, four poroelastic finite element models of human L2-L3 spinal motion segments, including the non-degeneration and the mild, moderate, and serious degeneration, were established. One-hour low-frequency vibrations with different frequencies were applied. Then, the dynamic mechanical properties of different degenerated lumbar models under the same vibration and the same lumbar model under vibrations at different frequencies were investigated. The results indicated and implied that the negative influences of 1-h vibration on the dynamic mechanical properties of the non-degenerated and mildly degenerated models were similar, but became obvious for the moderately and seriously degenerated models with time. Therefore, the damage caused by low-frequency vibration on the degenerated spinal motion segments was more serious compared with that on the healthy one. Meanwhile, the dynamic mechanical properties of the same lumbar model under vibrations at different frequencies expressed the negligible differences when the vibration frequency was not close to the lumbar natural frequency. Thus, the effects of the 1-h vibrations at different frequencies on one spinal motion segment were similar. Vibration frequency sensitivity analysis on the dynamic characteristics of human L2-L3 spinal motion segments with different degrees of degeneration.

16.
BMC Surg ; 20(1): 244, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33076895

RESUMO

BACKGROUND: Pediatric inguinal hernia (PIH) is a common disease in children. Laparoscopic hernia repair (LHR) has developed rapidly in recent years, but there are still different opinions compared with traditional open hernia repair (OHR). The purpose of this study was to compare the advantages and disadvantages of LHR and OHR in the treatment of pediatric inguinal hernia. METHODS: We performed a retrospective review of all children (< 14 years) who underwent repair of inguinal hernia in the pediatric surgery center of the Affiliated Hospital of Qingdao University from January 2015 to December 2015. We collected the medical records of all the children and analyzed the clinical characteristics, operation-related information and follow-up. RESULTS: In the OHR group, 202 cases underwent unilateral inguinal hernia repair, and 43 cases underwent bilateral inguinal hernia repair. In the LHR group, 168 cases underwent unilateral inguinal hernia repair, and 136 cases underwent bilateral inguinal hernia repair. There was a significant difference in the operation time between the two groups, but there were no significant differences in postoperative hospitalization time and incidence of ipsilateral recurrent hernia between the two groups. The incidence rates of metachronous contralateral hernia (MCH) and surgical site infection in LHR group were significantly lower than those in the OHR group. CONCLUSION: Our study shows that compared with OHR, LHR has the advantages of concealed incision, minimal invasiveness, reduced operation time, detection of contralateral patent processus vaginalis, and reduced incidence of MCH. In conclusion, LHR is safe and effective in the treatment of pediatric indirect inguinal hernia.

17.
Eur J Med Chem ; : 112917, 2020 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-33077263

RESUMO

Atg4, a pivotal macroautophagy/autophagy-related cysteine protein family, which regulate autophagy through either cleaving Atg8 homologs for its further lipidation or delipidating Atg8 homologs from the autophagosome. There are four homologs, Atg4A, Atg4B, Atg4C, and Atg4D. Among them, an increasing amount of evidence indicates that Atg4B possessed superior catalytic efficiency toward the Atg8 substrate, as well as regulates autophagy process and plays a key role in the development of several human cancers. Recently, efforts have been contributed to the exploration of Atg4B inhibitors or activators. In this review, we comprehensively clarify the function of Atg4B in autophagy and cancer biology, as well as the relationship between pharmacological function and structure-activity of small molecule drugs targeting Atg4B. The development of novel drugs targeting Atg4B could be well applied in the clinical practice.

19.
Sci Rep ; 10(1): 17633, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33077860

RESUMO

The distribution, characteristics of extracellular polymeric substances (EPS) of Phanerochaete chrysosporium under Pb2+ stress and the influence on Pb removal were investigated. Polysaccharides was found to be the main composition in both soluble EPS (SEPS) and bounded EPS (BEPS). More polysaccharides and protein in BEPS were detected with the increased Pb2+ concentration. The ratio of Pb amount distributed in BEPS to the total Pb removed by the fungal biomass gradually decreased from 91.66 to 61.27% in group with 50 mg/L of initial Pb2+, but kept at about 35% or 25% in groups with higher Pb2+. It implies that BEPS played a certain role in the lead removal process, and the role of BEPS was relatively more important in the removal of lower concentration of Pb2+ and in the initial period of Pb removal. With FTIR analysis and Pb2+ adsorption experiment, more effective functional groups and better Pb2+ adsorption capacity was demonstrated in BEPS than in SEPS. SEM-EDS analysis demonstrated that part of Pb immobilized in BEPS was in the form of Pb precipitation. The increased molecular weight in SEPS and more polysaccharides in BEPS were probably beneficial for the adhesion of Pb precipitation.

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