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1.
Nat Mater ; 21(1): 54-61, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34608284

RESUMO

The properties of quantum materials are commonly tuned using experimental variables such as pressure, magnetic field and doping. Here we explore a different approach using irreversible, plastic deformation of single crystals. We show that compressive plastic deformation induces low-dimensional superconductivity well above the superconducting transition temperature (Tc) of undeformed SrTiO3, with evidence of possible superconducting correlations at temperatures two orders of magnitude above the bulk Tc. The enhanced superconductivity is correlated with the appearance of self-organized dislocation structures, as revealed by diffuse neutron and X-ray scattering. We also observe deformation-induced signatures of quantum-critical ferroelectric fluctuations and inhomogeneous ferroelectric order using Raman scattering. Our results suggest that strain surrounding the self-organized dislocation structures induces local ferroelectricity and quantum-critical dynamics that strongly influence Tc, consistent with a theory of superconductivity enhanced by soft polar fluctuations. Our results demonstrate the potential of plastic deformation and dislocation engineering for the manipulation of electronic properties of quantum materials.

2.
Opt Express ; 31(15): 24566-24572, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37475280

RESUMO

The application of silicon nanocrystals (Si-NC) is somewhat limited due to their low luminescence intensity. Therefore, it is of interest to investigate methods for enhancing the luminescence intensity of Si-NC. In this study, phosphorus (P)-doped Si-NC with two different doping methods were prepared by electron beam thermal evaporation: in-situ doping (during synthesis) and ex-situ doping (after synthesis). The photoluminescence (PL) intensity and crystallinity of Si-NC can be enhanced through phosphorus doping. Moreover, a comparison between two different methods of Si-NC doping reveals that the luminescence intensity of in-situ P-doped Si-NC is superior to that of ex-situ P-doped Si-NC, which is increased by an order of magnitude compared to the PL intensity of undoped Si-NC.

3.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(4): 689-696, 2023 Aug 18.
Artigo em Zh | MEDLINE | ID: mdl-37534653

RESUMO

OBJECTIVE: To investigate the characteristics of exosomes derived from dental pulp stem cells (DPSCs) in the direction of odontogenic differentiation, to analyze the differences in microRNA expression profile between exosomes derived from undifferentiated and odontogenic DPSCs, and to analyze their possible signal transduction pathways. METHODS: (1) DPSCs were cultured in α minimum Eagle' s medium (α-MEM), and odontogenic DPSCs were cultured in odontogenic differentiation medium for 21 days, using alizarin red staining and alkaline phosphatase staining to identify the odontogenic differentiation. Exosomes from the cell supernatant were isolated respectively, named as dental pulp stem cells-exosomes (DPSCs-Exo) and dental pulp stem cells-odontogenic-exosomes (DPSCs-OD-Exo). The exosomes were identified by transmission electron microscopy, nanoparticle tracking analysis and Western blot. (2) The microRNA expression profiles of DPSCs-Exo and DPSCs-OD-Exo were investigated by microRNA microarray. To validate the result of the microRNA microarray, real-time quantitative polymerase chain reaction (real-time PCR) assay was applied on 3 most significantly differential expressed microRNA. Pathway analysis was taken to detect enriched pathways associated with the predicted target genes of microRNA. RESULTS: (1) The DPSCs were isolated and cultured in vitro showed typical fibroblast-like morphology. The odontogenic differentiated DPSCs were spindle-shaped, polygonal, and uniform in size. Odontogenic differentiation group showed a large number of dark deposits in alizarin red staining and the cells were darkly stained in alkaline phosphatase staining, while the cells in normal culture medium group did not show obvious dyeing. The DPSCs-Exo and DPSCs-OD-Exo had the same morphology, both showed bilayer membrane and cup-shape. The peak sizes of DPSCs-Exo and DPSCs-OD-Exo were (114.67±9.07) nm and (134.00±8.54) nm, respectively. The difference between the two was statistically significant. DPSCs-Exo and DPSCs-OD-Exo both expressed the markers of exosomes, tumor susceptibility gene (TSG)101 and CD63. (2) microRNA microarray results showed that the expression profiles of DPSCs-Exo and DPSCs-OD-Exo were different. Nineteen increased by more than two times, and one decreased by 64%. Real-time PCR results showed that the expression levels of microRNA-1246, microRNA-1246-100-5p and microRNA-1246-494-3p in DPSCs-OD-Exo were significantly up-regulated. The difference was statistically significant. microRNA target prediction database and gene signaling pathway database were used to analyze differentially expressed microRNA, and it was predicted that differentially expressed microRNA could target axis inhibition protein 2(AXIN2) gene and Wnt/ß-catenin signaling pathway. CONCLUSION: DPSCs-OD-Exo and DPSCs-Exo had differences in their microRNA expression profile. Those differentially expressed microRNA may be involved in the regulation of DPSCs odontogenic differentiation.


Assuntos
Exossomos , MicroRNAs , Exossomos/metabolismo , Fosfatase Alcalina/metabolismo , Polpa Dentária/metabolismo , Odontogênese/genética , Diferenciação Celular/fisiologia , MicroRNAs/genética , MicroRNAs/metabolismo , Células-Tronco/metabolismo , Células Cultivadas , Proliferação de Células
4.
Zhonghua Wai Ke Za Zhi ; 61(8): 656-665, 2023 Aug 01.
Artigo em Zh | MEDLINE | ID: mdl-37400208

RESUMO

Objective: To investigate the clinical outcome and preventive effect of polyetheretherketone(PEEK) rod hybrid surgery on proximal junction failure(PJF) after long-segment fusion of adult spinal deformity. Methods: A retrospective study was conducted to analyze patients with degenerative scoliosis/kyphosis who underwent long-segment decompression and fusion surgery at Department of Orthopedics, Peking University First Hospital from January 2017 to December 2021. A total of 75 patients were included in the study, including 14 males and 61 females, aged (67.2±6.8)years (range:55 to 84 years). According to the operation method chosen by the patients, the patients were divided into PEEK rod hybrid group (20 cases) and traditional titanium rod group (55 cases). The general information of the patients was collected, and the coronal and sagittal parameters of the spine were measured before operation, at 1 month after operation, and at the last follow-up. The clinical effect of surgery was judged by the visual analogue scale (VAS) and Oswestry disability index (ODI). Whether proximal junctional kyphosis (PJK) and PJF occurred during the follow-up and the time of occurrence were recorded. Comparisons between groups were performed using independent sample t test, Mann-Whitney U test, χ2 test and Fisher's exact probability method. The data before and after surgery in the same group were compared using the paired sample t test and the Wilcoxon test. Results: There were no significant differences in age, gender, body mass index, bone mineral density, distal instrumented vertebrae, surgical segments, osteotomy method, operation time, and intraoperative bleeding between the two groups (all P>0.05). The follow-up time of the PEEK rod group was shorter(M(IQR)16.5(4.8) vs. 25.0(12.0),Z=-4.230,P<0.01). There were no significant differences in coronal, sagittal parameters, VAS and ODI between the two groups before operation (all P>0.05). Postoperative coronal Cobb angle, pelvic incidence, pelvic tilt, sacral slope, lumbar lordosis, thoracic kyphosis, sagittal vertical axis (SVA), VAS and ODI were significantly improved in both groups(all P<0.05). At the last follow-up, the SVA of the PEEK rod hybrid group was(3.74±2.40)cm, which was significantly lower than that of the titanium rod group (6.28±4.06)cm (t'=-3.318, P=0.002). At the last follow-up, the ODI of the PEEK rod hybrid group was 30.7±6.1, significantly better than the titanium rod group 39.3±17.2(t=-3.203, P=0.046). PJK occurred in 2 patients (10.0%) in the PEEK rod hybrid group, and no PJF phenomenon was observed. In the titanium rod group, 18 patients (32.7%) developed PJK, and 11 patients (20.0%) developed PJF. There was a statistically significant difference in the incidence of PJF between the PEEK rod hybrid group and the titanium rod group (P=0.031). Conclusions: PEEK rod hybrid surgery can achieve good clinical results in the treatment of adult spinal deformities. Compared with traditional titanium rod surgery, it can significantly reduce the incidence of postoperative PJF and improve the clinical function of patients.


Assuntos
Cifose , Fusão Vertebral , Masculino , Feminino , Animais , Humanos , Adulto , Estudos Retrospectivos , Titânio , Cifose/cirurgia , Cifose/etiologia , Sacro , Osteotomia/efeitos adversos , Fusão Vertebral/métodos , Vértebras Lombares , Resultado do Tratamento , Complicações Pós-Operatórias/epidemiologia
5.
Lett Appl Microbiol ; 74(3): 462-469, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34878651

RESUMO

Resuscitation-promoting factors (Rpfs) belong to peptidoglycan hydrolases, which participate in recovery of dormant cells and promoting bacteria growth. In this study, the resuscitation promoting factor rpf2 gene of Rhodococcus erythropolis KB1 was expressed in Escherichia coli and purified by Ni2+ affinity chromatography. The purified recombinant fusion protein Rpf2 showed a closely 50 kDa band on sodium dodecyl sulphate polyacrylamide gel electrophoresis. The protein showed muralytic activity, with a specific activity of 1503 ± 123 U mg-1 when determined with 4-methylumbelliferyl-ß-d-N, N',N″-triacetotri-ylchitoside as substrate. It also showed protease activity when measured with azocasein as substrate, with a specific activity of 1528 ± 411 U mg-1 . The addition of the recombinant Rpf2 protein significantly increased petroleum degradation efficiency of the indigenous micro-organisms and the petroleum degradation rates increased from 30·86 to 43·45%, 45·20 and 49·23% in the treatment groups. The recombinant protein also increased the petroleum-degrading bacterial diversities enriched from the contaminated soils. The cultivable bacterial flora of the treatment groups supplemented with different concentrations of Rpf2 increased from 82 genera in 9 phyla to 116 genera in 16 phyla and 138 genera in 16 phyla respectively. Thirteen extra petroleum-degrading bacteria strains were isolated from the petroleum-contaminated soils in the groups containing the recombinant Rpf2.


Assuntos
Petróleo , Rhodococcus , Poluentes do Solo , Biodegradação Ambiental , Rhodococcus/genética , Solo , Microbiologia do Solo
6.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(10): 1441-1445, 2022 Oct 06.
Artigo em Zh | MEDLINE | ID: mdl-36274611

RESUMO

In this study, the data of pediatric diarrhea clinic of Gansu Provincial Maternal and Child Health Hospital from January 1, 2014 to December 31, 2018 and Tianshui First Hospital from January 1, 2015 to December 31, 2018 were collected. Standardized precipitation index (SPI) and meteorological drought composite index (MCI) were used as drought indicators. Quasi-Poisson generalized additive model was used to analyze the correlation between drought and pediatric diarrhea outpatient visits. During the study period, the dry days in Lanzhou city and Tianshui city were 298 and 379 days according to SPI-1, 303 and 398 days according to MCI, respectively. There were 57 147 and 18 703 cases of diarrhea in children aged 0-6 years in Gansu Provincial Maternal and Child Health Hospital and Tianshui First Hospital, respectively. MCI and SPI (SPI-1) based on monthly precipitation were negatively correlated with the number of pediatric diarrhea outpatients. Compared with the non-drought period, SPI-1 showed the strongest correlation between middle drought and pediatric diarrhea outpatients, with an increase of 13.4% (95%CI: 7.9%-19.3%) and 20.0% (95%CI: 12.7%-27.8%) in Lanzhou city and Tianshui city, respectively. According to MCI, the outpatients with diarrhea in Tianshui children increased by 60.5% (95%CI: 3.4%-149.0%) due to extreme drought.


Assuntos
Diarreia , Pacientes Ambulatoriais , Criança , Humanos , Diarreia/epidemiologia , Cidades , China/epidemiologia
7.
BMC Psychiatry ; 21(1): 550, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34753436

RESUMO

BACKGROUND: Suicidal ideation (SI) affects approximately 30-40% of those with major depressive disorder (MDD). To date, studies have examined the substantial humanistic and economic burden to caregivers of persons with MDD, however little is known of the impact of caring for persons with MDD when SI is present. This study examined the additional burden imposed on caregivers for persons with unipolar depression and SI in five major European countries. METHODS: A retrospective, cross-sectional analysis was conducted in five European countries using 2020 Europe National Health Wellness Survey (France, Germany, Italy, Spain and the United Kingdom) to compare differences in health and economic outcomes between caregivers of adults with unipolar depression and SI (CAUD-SI) and caregivers of adults with unipolar depression without SI (CAUD-nSI). The outcomes assessed included health-related quality of life (HRQoL; Medical Outcomes Study Short Form [SF-12v2]), health status (Short-Form 6 Dimension [SF-6D], EuroQol 5-Dimension 5-Level [EQ-5D-5L]), Work productivity and activity impairment (WPAI) and healthcare resource utilization (HRU). Linear mixed models and generalized linear mixed models adjusted for covariates were used to compare the two groups on outcomes of interest. RESULTS: Of 62,319 respondents, 0.89% (n = 554) were CAUD-SI and 1.34% (n = 837) were CAUD-nSI. In adjusted models, CAUD-SI reported greater humanistic burden than CAUD-nSI, with lower HRQoL (PCS: 42.7 vs. 45.0, p < 0.001 and MCS: 37.5 vs. 38.9, p = 0.007) and health status (SF-6D: 0.57 vs 0.60, p < 0.001 and EQ-5D-5L: 0.58 vs 0.66, p < 001). CAUD-SI respondents reported significantly higher economic burden than CAUD-nSI respondents for WPAI (percent activity impairment: 64.9% vs. 52.5%, p = 0.026) and HRU (provider visits: 10.0 vs. 7.9, p < 0.001, emergency room visits: 1.49 vs. 0.73, p < 0.001 and hospitalizations: 1.03 vs. 0.52, p < 0.001). CONCLUSION: In five European countries, caregivers of adults with depression and SI experience additional humanistic and economic burden than caregivers of adults with depression and no SI. Distinguishing caregiver groupings and their unique burden provide important insights for providing targeted support and interventions for both the patient and caregiver.


Assuntos
Transtorno Depressivo Maior , Qualidade de Vida , Adulto , Efeitos Psicossociais da Doença , Estudos Transversais , Depressão , Transtorno Depressivo Maior/terapia , Europa (Continente) , Humanos , Estudos Retrospectivos , Ideação Suicida
8.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(4): 734-739, 2021 Aug 18.
Artigo em Zh | MEDLINE | ID: mdl-34393237

RESUMO

OBJECTIVE: To investigate clinical efficacy and safety of single and double segmental percutaneous lumbar discectomy for young and middle-aged patients with double-segment disc herniation. METHODS: Retrospective analysis was undertaken for 32 young and middle-aged patients with percutaneous endoscopic lumbar discectomy (PELD) in the treatment of double-segment lumbar disc herniation from January 2015 to October 2018 in Peking University First Hospital. In the study, 18 cases were treated with single-segment treatment and 14 cases with double-segment treatment. Visual analogue score (VAS) and oswestry disability index (ODI) assessment were used to compare clinical symptom outcomes before surgery, 3 months after surgery and at the last follow-up. Macnab criteria were used to assess the patients' overall satisfaction after surgery. Imaging parameters included lumbar lordosis, intervertebral height at each segment and endplate angle of lesion segment on the X-ray. And Michigan State University(MSU) rating and Pfirrmann scoring system were used to evaluate the grade of disc herniation and disc degeneration respectively on magnetic resonance imaging (MRI). The perioperative parameters included the surgeon, anesthesia method, operation time, postoperative hospital stay, postoperative bracing time and perioperative complications. RESULTS: The mean follow-up time was (26.78±10.64) months. There was no significant difference in the follow-up time and baseline information between the two groups(P > 0.05). ODI scores 3 months post-operatively and at the last follow-up were lower in the double segment (P < 0.05). The ODI improvement was also more significant in the double-segment group at the last follow-up (P < 0.05). There was no significant difference in radiographic parameters at baseline (P>0.05). MSU scale for the primary segment was significantly lowered after both operations (P < 0.05). MSU scale for secondary segment was significantly lowered in double segment group but not in single segment group. Other imaging parameters were similar between the two groups (P > 0.05). The operation time of the single-segment group was significantly shorter than that of the double-segment group(P < 0.001). No perioperative complications were found in either group, but three patients underwent secondary lumbar surgery during the postoperative follow-up period in the single-segment group. CONCLUSION: For young and middle-aged patients with double-segment disc herniation, this study suggests double-segment PELD may be more advantageous than single-segment PELD in terms of asuring clinical efficacy without increasing perioperative risks.


Assuntos
Discotomia Percutânea , Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Discotomia , Endoscopia , Humanos , Degeneração do Disco Intervertebral/cirurgia , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
9.
Fa Yi Xue Za Zhi ; 37(2): 248-255, 2021 Apr.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-34142488

RESUMO

ABSTRACT: Herbicides are a kind of chemical or biological agents that can effectively destroy or inhibit weed growth. Because of the widespread and frequent use of herbicides, herbicide poisonings have often been reported. At present, the main species reported to have caused poisoning are paraquat, diquat, glyphosate, and glufosinate. The main instrumental analysis method is LC-MS. This paper reviews the research progress on analysis methods of common herbicides in biological material and their application, summarizes the sample pretreatment and instrumental analysis situation of qualitative and quantitative analysis of herbicides in biological material, and collects test data of actual poisoning cases, to provide reference for clinical diagnosis and treatment and forensic identification of herbicide poisoning.


Assuntos
Herbicidas , Cromatografia Líquida , Espectrometria de Massas , Paraquat
10.
Fa Yi Xue Za Zhi ; 37(4): 493-499, 2021 Aug.
Artigo em Zh | MEDLINE | ID: mdl-34726001

RESUMO

ABSTRACT: Objective To study the metabolic transformation pathways of 4F-MDMB-BUTINACA in vivo by establishing zebrafish models. Methods Six adult zebrafish were randomly divided into blank control group and experimental group, with three fish in each group. After the zebrafish in the experimental group were exposed to 1 µg/mL 4F-MDMB-BUTINACA for 24 h, they were transferred to clean water and cleaned three times, then pretreated for instrumental analysis. The zebrafish in blank control group were not exposed to 4F-MDMB-BUTINACA. Mass spectrometry and structural analysis of 4F-MDMB-BUTINACA and its metabolites were conducted by liquid chromatography-high resolution mass spectrometry and Mass Frontier software. Results A total of twenty-six metabolites of 4F-MDMB-BUTINACA were identified in zebrafish, including eighteen phase Ⅰ metabolites and eight phase Ⅱ metabolites. The main metabolic pathways of phase Ⅰ metabolites of 4F-MDMB-BUTINACA in zebrafish were ester hydrolysis, N-dealkylation, oxidative defluorination and hydroxylation, while the main metabolic pathway of phase Ⅱ metabolites was glucuronidation. Conclusion Metabolite Md24 (ester hydrolysis) and Md25 (ester hydrolysis combined with dehydrogenation) would be recommended to be potentially good biomarkers for abuse of 4F-MDMB-BUTINACA.


Assuntos
Canabinoides , Drogas Ilícitas , Animais , Cromatografia Líquida , Microssomos Hepáticos/química , Peixe-Zebra
11.
J Biol Regul Homeost Agents ; 34(4): 1297-1306, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32907315

RESUMO

The aim of this study was to investigate the differential expression of micro ribonucleic acid (miR)- 125b in acute myocardial infarction (AMI) cases, and to explore the mechanism by which it affects cardiac function. Sprague-Dawley rats were used for AMI modeling, and the expression of miR-125b in the myocardial tissues of AMI rats was detected via fluorescence quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Thereafter, the target genes of miR-125b were collected and uploaded to WenGestalt for gene ontology (GO) and pathway enrichment analyses. In-vitro experiments were then applied to determine the p38-sirtuin 1 (Sirt1)-p53 expression change and cardiomyocyte apoptosis under down-regulation of miR-125b. Next, the interaction between miR-125b and its target genes was verified by luciferase reporter gene assay. The expression of miR-125b in the cardiac tissues was decreased in theAMI group compared with that in the Sham group (p<0.05). The luciferase reporter gene assay confirmed that p38 was the target gene of miR-125b. Furthermore, the down-regulated expression of miR-125b in H9C2 cells up-regulated the protein expressions of p38 and phosphorylated p38, thus activating the Sirt1-p53 signaling pathway. Moreover, the down-regulation of miR-125b expression in H9C2 cells gave rise to the elevated apoptosis rate, and the down-regulated expression of miR-125b induced cardiomyocyte apoptosis through activating the p38-Sirt1-p53 signaling pathway.


Assuntos
Infarto do Miocárdio , Animais , Apoptose/genética , Sistema de Sinalização das MAP Quinases , MicroRNAs/genética , Infarto do Miocárdio/genética , Ratos , Ratos Sprague-Dawley , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
12.
BMC Anesthesiol ; 20(1): 181, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32698766

RESUMO

BACKGROUND: Individualized fluid management (IFM) has been shown to be useful to improve the postoperative outcome of patients undergoing major abdominal surgery. A limited number of clinical studies have been done in orthopaedic patients and have yielded conflicting results. We designed the present study to investigate the clinical impact of IFM in patients undergoing major spine surgery. METHODS: This is a before-after study done in 300 patients undergoing posterior spine arthrodesis. Postoperative outcomes were compared between control group implementing standard fluid management (n = 150) and IFM group (n = 150) guided by fluid protocol based on continuous stroke volume monitoring and optimization. The primary outcome measure was the proportion of patients who developed one or more complications within 30 days following surgery. RESULTS: During surgery, patients received on average the same volume of crystalloids (7.4 vs 7.2 ml/kg/h) and colloids (1.6 vs 1.6 ml/kg/h) before and after the implementation of IFM. During 30 days following surgery, the proportion of patients who developed one or more complications was lower in the IFM group (32 vs 48%, p < 0.01). This difference was mainly explained by a significant decrease in post-operative nausea and vomiting (from 38 to 19%, p < 0.01), urinary tract infections (from 9 to 1%, p < 0.01) and surgical site infections (from 5 to 1%, p < 0.05). Median hospital length of stay was not affected by the implementation of IFM. CONCLUSION: In patients undergoing major spine surgery, the implementation of IFM was associated with a significant decrease in postoperative morbidity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02470221 . Prospectively registered on June 12, 2015.


Assuntos
Hidratação/métodos , Complicações Pós-Operatórias/epidemiologia , Fusão Vertebral/métodos , Volume Sistólico/fisiologia , Adulto , Idoso , Coloides/administração & dosagem , Estudos Controlados Antes e Depois , Soluções Cristaloides/administração & dosagem , Feminino , Humanos , Cuidados Intraoperatórios/métodos , Masculino , Pessoa de Meia-Idade , Náusea e Vômito Pós-Operatórios/epidemiologia , Medicina de Precisão/métodos , Estudos Prospectivos , Coluna Vertebral/cirurgia , Resultado do Tratamento
13.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(1): 102-108, 2020 Sep 30.
Artigo em Zh | MEDLINE | ID: mdl-33550343

RESUMO

OBJECTIVE: To investigate the factors affecting the trueness of finish lines of full crown preparations in digital impressions. METHODS: A full crown preparation of the right maxillary molar was prepared on the standard resin dentition model, the trueness of the finish lines, the full crown preparation in the whole dentition and the isolated full crown preparation were measured respectively. Detection of scanning trueness of the finish lines of the full crown preparation in the whole dentition: (1) Using Imetric scanner to scan the full crown preparation, obtaining STL (Stereo lithographic) format data as the reference true value; (2) Using CEREC Omnicam oral scanner and 3Shape TRIOS oral scanner to scan the full crown preparation, obtaining all the STL format data, import Geomagic Studio 2013 software, extraction of images and data of the complete finish lines or local finish lines (mesial, distal, buccal, lingual) of the full crown preparation, then using the data to 3D Compare Analysis with the reference true value, outputting RMS (root mean square) values which could evaluate the scanning trueness, the lower RMS value was, the lower the trueness was. The detection of scanning trueness of the finish lines of the isolated full crown preparation: (1) the anterior and posterior adjacent teeth of the preparation were removed to establish the model of the isolated full crown preparation; (2) CEREC Omnicam oral scanner and 3Shape TRIOS oral scanner were used to scan the isolated preparations, and each group was repeated 6 times. Data collection and analysis were the same as the first part, that is, detection of scanning trueness of finish lines of the full crown preparation in the whole dentition. RESULTS: In the whole dentition, (1) the RMS value [(44±7) µm] of CEREC Omnicam oral scanner scanning complete finish lines was greater than that of 3Shape TRIOS oral scanner [(35±6) µm](P < 0.05). (2) the RMS values of the mesial [(45±9) µm], buccal [(38±3) µm] and lingual [(40±3) µm] finish lines in CEREC Omnicam oral scanner scanning were all lower than that in distal [(63±7) µm](P < 0.05), and the RMS values in mesial were higher than that in buccal and lingual (P>0.05). The RMS values of 3Shape TRIOS oral scanner scanning mesial and distal finish lines were significantly higher than those of the buccal and lingual side (P>0.05), in which:(45±8) µm in mesial, (50±10) µm in the distal, (33±8) µm in the buccal and (33±6) µm in the lingual side. The RMS value of CEREC Omnicam oral scanner scanning distal finish line was greater than that of 3Shape TRIOS oral scanner (P < 0.05). Without adjacent teeth, (1) the RMS values of the complete finish lines of CEREC Omnicam oral scanner and 3 Shape TRIOS oral scanner were significantly reduced (P < 0.05), including CEREC Omnicam oral scanner (34±3) µm and 3 Shape TRIOS oral scanner (26±4) µm; (2) the RMS values of the buccal and lingual finish lines of CEREC Omnicam oral scanner and 3Shape TRIOS oral scanner showed no significant changes (P>0.05), among which, CEREC Omnicam oral scanner buccal (44±7) µm, lingual (43±3) µm, 3Shape TRIOS oral scanner buccal (29±5) µm, lingual (40±7) µm. The RMS values of CEREC Omnicam oral scanner and 3Shape TRIOS oral scanner were significantly reduced and there was no significant difference between them (P>0.05). CEREC Omnicam oral scanner (32±8) µm and 3Shape TRIOS oral scanner (32±6) µm. The RMS values of the distal finish lines of CEREC Omnicam oral scanner and 3 Shape TRIOS oral scanner also decreased significantly (P < 0.05), and CEREC Omnicam oral scanner (38±3) µm decreased more significantly, similar to 3Shape TRIOS oral scanner (36±1) µm, P>0.05. CONCLUSION: When adjacent teeth exist in the full crown preparation, the mesial and distal parts of the finish line will be blocked by adjacent teeth, which will affect the trueness of the local finish line, and ultimately reduce the trueness of the complete finish line.


Assuntos
Desenho Assistido por Computador , Dente , Assistência Odontológica , Técnica de Moldagem Odontológica , Humanos , Imageamento Tridimensional , Modelos Dentários , Software
14.
Beijing Da Xue Xue Bao Yi Xue Ban ; 52(6): 1117-1123, 2020 Dec 18.
Artigo em Zh | MEDLINE | ID: mdl-33331324

RESUMO

OBJECTIVE: To explore the conversion of resin monomer, the change of inorganic component and the influencing factors on the oxygen inhibition layer formed on the cured surface of resin cement. METHODS: Three kinds of resin cement were divided into three groups: (1) light-cured group: RelyX Veneer, NX3 (light-cured), Variolink N; (2) dual-cured group: RelyX U200 Automix, NX3 (dual-cured), Multilink Speed; (3) chemically-cured group, and the above 3 types of dual-cured resin cement cured without illumination could be used as chemically-cured resin cement. Each sample was provided with and without oxygen exposure of two matching surfaces, cured respectively, and the variables of light intensity and illumination time were set in the light-cured group and the dual-cured group. Scanning electron microscopy was used to observe the samples' surface morphology. Energy dispersive spectrometer was used to analyze the samples' composition of surface elements. Confocal Raman spectroscopy was used to measure the monomer conversion of resin cement and to obtain the thickness of the oxygen inhibition layer. RESULTS: (1) On the surface of cured resin cement, the weight percentage of oxygen element in the aerobic side was higher than that in the anaerobic side (P < 0.05), and the weight percentage of inorganic element was lower than that in the anaerobic side (P < 0.05). (2) The surface monomer conversion of the cured resin cement on the aerobic surface was significantly lower than that on the anaerobic surface (P < 0.05), and the surface monomer conversion on the aerobic surface and the anaerobic surface was the lowest in the chemically-cured group (P < 0.05), the dual-cured group was the highest (P < 0.05), and the light-cured group was between them. With the increase of light intensity or illumination time, the surface monomer conversion increased (P < 0.05). (3) The thickness of the oxygen inhibition layer was the thickest in the chemically-cured group [(40.27±2.81) µm](P < 0.05), the thinnest in the dual-cured group [(21.87±5.42) µm](P < 0.05) and light-cured group [(23.73±3.84) µm] was between them. With the increase of light intensity or illumination time, the thickness of the oxygen inhibition layer of resin cement decreased (P < 0.05). CONCLUSION: When resin cement is exposed to oxygen, it will form an oxygen inhibition layer, its surface's inorganic filler is less, the surface monomer conversion is lower. The surface monomer conversion and the thickness of oxygen inhibition layer are affected by curing mode and illumination factors.


Assuntos
Oxigênio , Cimentos de Resina , Teste de Materiais
15.
Beijing Da Xue Xue Bao Yi Xue Ban ; 52(1): 43-50, 2020 Feb 18.
Artigo em Zh | MEDLINE | ID: mdl-32071462

RESUMO

OBJECTIVE: To evaluate the uptake of exosomes by stem cells from apical papilla (SCAP), thus to provide experimental basis for mechanism of the exosomes endocytosis by SCAP. METHODS: (1) Exosomes of dental pulp stem cells (DPSCs) were isolated by hypercentrifugation combined with ultrafiltration method. The exosomes were identified by transmission electron microscopy, nanoparticle tracking analysis and western blot. (2) PKH-26 membrane labeling technology was used to mark the DPSCs derived exosomes. The labeled exosomes were co-cultured with SCAP at 37 °C as positive control group, and co-cultured with SCAP at 4 °C as the low-temperature treatment group, while the negative control group was set up. (3) Using clathrin-mediated endocytosis inhibitor chlorpromazine (CPZ, 10 µmol /L) as CPZ group, caveolae-mediated endocytosis Genistein (200 µmol/L) as Genistein group, and macropinocytosis inhibitor LY294002 (50 µmol/L) as LY294002 group to treat the SCAP respectively. Solvent control group (DMSO group) was set. Immunofluorescence staining was used to detect the red fluorescence SCAP and flow cytometry was used to analyze the proportion of SCAP labeled with red fluorescence. RESULTS: (1) The bilayer membrane and cup-shaped appearance of representative exosomes were observed. The peak of the size of DPSCs-derived exosomes was at 144 nm. The exosomes expressed exosomal marker proteins TSG101 and CD63, but not GAPDH which was the cellular internal control protein. (2) Immunofluorescence staining showed that after being co-cultured at 37 °C for 6 hours, red fluorescence could be detected in SCAP but it could not be detected after being co-cultured at 4 °C for 6 hours. After endocytosis inhibition, the red fluorescence in SCAP was reduced. Flow cytometry showed that the proportion of SCAP labeled with red fluorescence in positive group was 35.0%, in negative control group was 0.5%, and in solvent control group was 29.7%, in CPZ group, Genistein group and Genistein group were reduced to 13.7%, 16.6%, and 20.9%, respectively. CONCLUSION: SCAP could uptake the DPSCs derived exosomes, and low temperature could inhibit this process. The exosomes uptake of SCAP was mediated by the clathrin endocytosis pathway, caveolae-mediated endocytosis and macropinocytosis pathway.


Assuntos
Exossomos , Papila Dentária , Endocitose , Células Epiteliais , Células-Tronco
16.
Zhongguo Zhong Yao Za Zhi ; 45(19): 4792-4797, 2020 Oct.
Artigo em Zh | MEDLINE | ID: mdl-33164447

RESUMO

"Shengdeng" is a traditional Tibetan medicine, which has many synonyms. It is complex in origin and serious in mi-xing. In order to clarify the origin of "Shengdeng" and its medicinal use, this paper makes a textual research on the name, variety and efficacy of "Shengdeng" by consulting Tibetan medicine classics such as The Four Medical Trantras and Jingzhu Materia Medica, combined with modern literature of Tibetan medicine. It is clear that the synonyms, primitive species, mainstream varieties and functions of Tibetan medicine "Shengdeng". The collation and analysis of the literature shows that "Shengdeng" has effects of treating rheumatism, drying "Huangshui", detumescence and relieving pain, and is mainly used for the treatment of rheumatoid arthritis in Tibetan medicine. Its original varieties include 14 species of plants belonging to 6 families: Spicaceae, Rhamnaceae, Cephalotaxus, Leguminosae, Hematoxylaceae and Taxaceae. Combined with the collection of legal standards at all levels, the distribution of resources and the application of clinical prescriptions, it is considered that the mainstream species of "Shengdeng" are Rhamnella gilgitica, Xanthoceras sorbifolia, Rhamnus parvifolia. As a substitute, Acacia catechu is also widely used in clinic. The literature review and variety textual research on Tibetan medicine "Shengdeng" is helpful to improve the safety, effectiveness and quality controllability of its clinical application, and provide scientific basis for its further standard setting, pharmacodynamics research, new drug development and so on.


Assuntos
Fabaceae , Plantas Medicinais , Rhamnaceae , Dessecação , Medicina Tradicional Tibetana
17.
J Cell Biochem ; 120(3): 4333-4341, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30260036

RESUMO

Itraconazole is an FDA-approved antifungal agent, which has been reported to possess promising anticancer activities in recent years. This study investigates the antiproliferative effects of itraconazole on pancreatic cancer cells and the molecular mechanism of its apoptosis-inducing effects. In this study, our results showed that itraconazole inhibited the growth of pancreatic cancer cells in vitro, and it also significantly inhibited the tumor growth of CFPAC-1 xenografts in vivo. Itraconazole induced apoptosis through ROS generation and mitochondrial membrane depolarization. A Bak-1 activation dependent apoptosis was identified in CFPAC-1 cells. These data suggested that itraconazole exhibited antiproliferative effects in pancreatic cancer cells by inducing apoptosis through Bak-1 activation.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Itraconazol/farmacologia , Neoplasias Pancreáticas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Neoplasias Pancreáticas/patologia , Espécies Reativas de Oxigênio/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Water Sci Technol ; 79(10): 2005-2012, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31294717

RESUMO

Polyvinyl alcohol (PVA) is the main pollutant in printing and dyeing wastewaters. This pollutant exhibits great demand, poor biodegradability and refractory degradation. In this study, PVA wastewater treatment experiments were conducted in a stably operating baffled anaerobic bioreactor (ABR) by using simulated PVA wastewater. The PVA degradation pathway and mechanism of the mixed dominant PVA-degrading bacterial strains were identified through the analysis of their degradation products. From the results, we inferred that PVA was degraded in a stepwise process under the synergistic action of different extracellular and intracellular enzymes produced by the mixed dominant PVA-degrading bacterial strains. In this process, PVA was first degraded into ketones, fatty acids and alcohols. It was then regenerated into acetic acid, hydrogen and carbon dioxide. Finally, these substances could be further utilized by methanogens. PVA was thus degraded completely. This study may serve as a reference for future works on the degradation of PVA in the ecological environment. It may also guide the sustainable development of PVA.


Assuntos
Biodegradação Ambiental , Reatores Biológicos , Álcool de Polivinil , Bactérias , Águas Residuárias
19.
Beijing Da Xue Xue Bao Yi Xue Ban ; 51(5): 893-899, 2019 Oct 18.
Artigo em Zh | MEDLINE | ID: mdl-31624395

RESUMO

OBJECTIVE: To evaluate the change of cell surface CXC chemokine receptor 4 (CXCR4) expression of stem cells from apical papilla (SCAP) after the inhibition of endocytotic pathway, thus to provide experimental basis for the mechanism of SCAP migration. METHODS: The immunofluorescence analysis was conducted to examine the co-expression of CXCR4 and endocytotic compartments, including early endosomes, recycling endosomes and lysosomes in SCAP. Several Rab proteins were applied as markers of organelles in the endocytotic pathway, including Rab5 for early endosomes, Rab11A for recycling endosomes, and Lamp1 for lysosomes. The co-localization of CXCR4 with these endodontic compartments was further observed by proximity ligation assay (PLA). SCAP was treated with two kinds of endocytotic inhibitors, Blebbistatin and Dynasore, at a concentration of 80 µmol/L, respectively. The conditioning time was 1 hour. Flow cytometry was carried out to evaluate the proportion of SCAP that expressed CXCR4 on cell surface. The data were analysed by analysis of variance (ANOVA). RESULTS: The red staining of CXCR4 on immunofluorescence confocal microscopy predominantly overlapped with the green staining of Rab5 and Rab11A, and partly overlapped with Lamp1. It indicated that most CXCR4 molecules were located in early endosomes and recycling endosomes, and some were located in lysosomes. The PLA results revealed that the co-localizaiton of CXCR4 with endocytotic compartments could be observed in early endosomes, recycling endosomes and lysosomes. According to the results of flow cytometry, the proportion of SCAP that expressed CXCR4 on cell surface was as low as 0.13%±0.10%. After the inhibition of endocytosis by pretreating the cells with the following two inhibitors, Blebbistatin and Dynasore, the percentage of SCAP that positively expressed CXCR4 on cell surface was significantly increased to 13.34%±1.31% in Blebbistatin group and 4.03%±0.92% in Dynasore group (F=16.721, P<0.001). Moreover, the number of SCAP that expressed CXCR4 on cell surface in Blebbistatin group was significantly higher than that in Dynasore group (P<0.001). CONCLUSION: The inhibition of endocytotic pathway could increase the number of SCAP that expressed CXCR4 on cell surface, and provide potency for the migration of SCAP.


Assuntos
Endocitose , Receptores CXCR4 , Endossomos , Lisossomos , Células-Tronco
20.
Beijing Da Xue Xue Bao Yi Xue Ban ; 50(2): 347-351, 2018 Apr 18.
Artigo em Zh | MEDLINE | ID: mdl-29643538

RESUMO

OBJECTIVE: To investigate the clinical effectiveness of polytheretherketone (PEEK) cages assisted anterior cervical discetomy and fusion (ACDF) to treat cervical spondylosis with sympathetic symptoms. METHODS: Retrospective analysis was undertaken for 39 patients who were diagnosed as cervical spondylosis with sympathetic symptoms and underwent ACDF with PEEK cages. Radiographs obtained before surgery, after surgery, and at the final follow-up were assessed for quality of fusion. The following criteria were used for assessing radiographic success of fusion: (1) endplate obliterated with no lucent lines; (2) obliteration of disc space by bony trabeculae; (3) less than 2°of intervertebral motion or 2 mm of motion between the spinous processes at the operated segment on flexion-extension lateral radiographs. The sympathetic symptoms including vertigo, headache, tinnitus, nausea and vomiting, heart throb, hypomnesia and gastroenterological discomfort were scored by 20-point system preoperatively, 2 months postoperatively and at the final follow-up. The recovery rate and clinical satisfaction rate were also evaluated. Surgical complications were also assessed. RESULTS: They were followed up for at least one year. The mean follow-up was 15.6 months. Radiographs of the cervical spine at the last follow-up revealed a solid fusion with no signs of a pseudoarthrosis in 36 cases. In two patients delayed union and bony fusion were achieved at the end of 9 and 11 months. Pseudoarthosis was found in 1 case but the patient had no symptoms. The score of sympathetic symptoms before surgery, 2 months after surgery and at the final follow-up were 8.4±1.0,2.2±0.3,and 2.4±0.3, respectively. There were 22 excellent cases, 15 good cases, 1 fair case and 1 bad case in terms of RR. Good to excellent results were attained in 95% of theses patients. The sympathetic symptoms improved in all the patients and the score was significantly improved after surgery. There was one patient who had cerebral spinal fluid leakage but he recovered one week after surgery. Two patients felt a mild swallowing discomfort, but it disappeared within one month after surgery. Subcutaneous hematoma occurred in one patient due to obstructed drainage. It was cleared two days after surgery. CONCLUSION: Cervical spondylosis patients with sympathetic symptoms may be managed successfully with ACDF using PEEK cages. Successful clinical results regarding symptom improvement and general satisfaction with the surgical procedure depend not only on obtaining successful decompression and radiographic fusion but also on patient selection.


Assuntos
Discotomia , Fusão Vertebral , Espondilose/cirurgia , Vértebras Cervicais/cirurgia , Descompressão Cirúrgica , Humanos , Masculino , Náusea , Procedimentos Neurocirúrgicos , Radiografia , Estudos Retrospectivos , Espondilose/diagnóstico por imagem , Resultado do Tratamento , Vômito
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