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1.
J Inorg Biochem ; 225: 111616, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34555601

RESUMO

Ruthenium-containing complexes have emerged as good alternative to the currently used platinum-containing drugs for malignant tumor therapy. In this work, cytotoxic effects of recently synthesized ruthenium polypyridyl complexes [Ru(bpy)2(CFPIP)](ClO4)2 (bpy = 2,2'-bipyridine, CFPIP = (E)-2-(4-fluorostyryl)-1H-imidazo[4,5-f][1,10]phenanthroline, Ru(II)-1), [Ru(phen)2(CFPIP)](ClO4)2 (phen = 1,10-phenanthroline, Ru(II)-2) and [Ru(dmb)2(CFPIP)](ClO4)2 (dmb = 4,4'-dimethyl-2,2'-bipyridine, Ru(II)-3) toward different tumor cells were investigated in vitro and compared with cisplatin, the most widely used chemotherapeutic drug against hepatocellular carcinoma (HepG-2). The results demonstrate that target complexes show excellent cytotoxicity against HepG-2 cells with low IC50 value of 21.4 ± 1.5, 18.0 ± 2.1 and 22.3 ± 1.7 µM, respectively. It was important noting that target Ru(II) complexes exhibited better antitumor activity than cisplatin (IC50 = 28.5 ± 2.4 µM) against HepG-2 cells, and has no obvious toxicity to normal cell LO2. DNA binding results suggest that Ru(II)-1, Ru(II)-2 and Ru(II)-3 interact with CT DNA (calf thymus DNA) through intercalative mode. Complexes exerted its antitumor activity through increasing anti-migration and inducing cell cycle arrest at the S phase. In addition, the apoptosis was tested by AO (acridine orange)/EB (ethidium bromide) staining and flow cytometry. Mitochondrial membrane potential (MMP), reactive oxygen species (ROS), and colocalization tests were also evaluated by ImageXpress Micro XLS system. Overall, the results show that the ruthenium polypyridyl complexes induce apoptosis in HepG-2 cells through ROS-mediated mitochondria dysfunction pathway.

3.
Andrologia ; 53(9): e14122, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34319588

RESUMO

Radical prostatectomy, radiotherapy and active surveillance are three widely used treatment options for patients with low-risk prostate cancer, but the relative effects are controversial. We searched PubMed, Embase and Web of Science until June 2020, focusing on the studies comparing the effect of radical prostatectomy, radiotherapy and active surveillance in patients with low-risk prostate cancer. Through the random-effects model, dichotomous data were extracted and summarised by odds ratio with a 95% confidence interval. Twenty-two studies containing 185,363 participants were pooled for the comprehensive comparison. The Bayesian mixed network estimate demonstrated the cancer-specific mortality of radical prostatectomy was significantly lower than active surveillance (OR, 0.46; 95% CI 0.34-0.64) and external beam radiation therapy (OR, 0.66; 95% CI 0.46-0.96), but not brachytherapy (OR, 0.63; 95% CI 0.41-1.03). The brachytherapy demonstrated the best treatment ranking probability results in terms of all-cause mortality, while no significant difference was observed when compared with other three treatment modalities. Brachytherapy and radical prostatectomy were associated with a similar risk of cancer-specific mortality, and both of them were significantly superior to active surveillance and external beam radiation therapy; nevertheless, there was no significant difference among the aforementioned treatment methods in all-cause mortality.


Assuntos
Braquiterapia , Neoplasias da Próstata , Teorema de Bayes , Humanos , Masculino , Metanálise em Rede , Prostatectomia , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia
4.
J Magn Reson ; 327: 106975, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33873092

RESUMO

This paper provides a detailed analysis of three common NMR probe circuits (untuned, tuned, and impedance-matched) and studies their effects on multi-pulse experiments, such as those based on the Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence. The magnitude of probe dynamics effects on broadband refocusing pulses are studied as a function of normalized RF bandwidth. Finally, the probe circuit models are integrated with spin dynamics simulations to design hardware-specific RF excitation and refocusing pulses for optimizing user-specified metrics such as signal-to-noise ratio (SNR) in grossly inhomogeneous fields. Preliminary experimental results on untuned probes are also presented.

5.
Adv Healthc Mater ; 10(11): e2100024, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33890420

RESUMO

Scaffolds for tissue engineering aim to mimic the native extracellular matrix (ECM) that provides physical support and biochemical signals to modulate multiple cell behaviors. However, the majority of currently used biomaterials are oversimplified and therefore fail to provide a niche required for the stimulation of tissue regeneration. In the present study, 3D decellularized ECM (dECM) scaffolds derived from mesenchymal stem cell (MSC) spheroids and with intricate matrix composition are developed. Specifically, application of macromolecular crowding (MMC) to MSC spheroid cultures facilitate ECM assembly in a 3D configuration, resulting in the accumulation of ECM and associated bioactive components. Decellularized 3D dECM constructs produced under MMC are able to adequately preserve the microarchitecture of structural ECM components and are characterized by higher retention of growth factors. This results in a stronger proangiogenic bioactivity as compared to constructs produced under uncrowded conditions. These dECM scaffolds can be homogenously populated by endothelial cells, which direct the macroassembly of the structures into larger cell-carrying constructs. Application of empty scaffolds enhances intrinsic revascularization in vivo, indicating that the 3D dECM scaffolds represent optimal proangiogenic bioactive blocks for the construction of larger engineered tissue constructs.


Assuntos
Células-Tronco Mesenquimais , Engenharia Tecidual , Células Endoteliais , Matriz Extracelular , Células-Tronco , Tecidos Suporte
6.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(2): 311-315, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-33812392

RESUMO

OBJECTIVE: To investigate the clinical features and prognostic factors of acute lymphoblastic leukemia (ALL) children with P2RY8-CRLF2 gene rearrangement. METHODS: A total of 108 children with B-cell ALL (B-ALL) were diagnosed and systematically treated according to Chinese Children's Leukemia Group (CCLG) -ALL 2008 in our hospital from January 2016 to December 2016. The 108 patients were divided into two groups according to the result of mutiplex polymerase chain reaction: group with P2RY8-CRLF2 gene rearrangement and group without P2RY8-CRLF2 gene rearrangement. The ALL children with P2RY8-CRLF2 gene rearrangement were all treated by CCLG-ALL 2008 high-risk group (HR) regimens, and the ALL children in group without P2RY8-CRLF2 gene rearrangement received different intensity chemotherapy according to clinical risk classification. RESULTS: Five (4 male and 1 female) out of 108 patients with B-ALL had P2RY8-CRLF2 gene rearrangement. In the 5 B-ALL patients with P2RY8-CRLF2 gene rearrangement, the median age of the was 4 (2-6) years old and the median WBC count was 26.2 (2.46-525.1)×109/L. These patients presented different immunophenotype, including 3 cases of common B-ALL and 2 cases of pre B-ALL. Four patients carried a normal karyotype and 1 patient carried 46, XY, der (20) [22]/46, XY[2]. For the children with P2RY8-CRLF2 gene rearrangement, 1 patient (20%) could not achieve complete remission (CR), and minimal residual disease (MRD) of 2 patients (40%) was higher than 1% on day 33 of induction chemotherapy; while in group without P2RY8-CRLF2 gene rearrangement, all the patient achieved CR, and MRD in 6 patients (5.8%) was higher than 1% on day 33 of induction chemotherapy. The 3 year event-free survival (EFS) of ALL children in group with P2RY8-CRLF2 gene rearrangement was significantly lower than that in group without P2RY8-CRLF2 gene rearrangement (60.0%±21.9% vs 85.9%±3.9%) (P<0.05). CONCLUSION: The early treatment response and prognosis of ALL children with P2RY8-CRLF2 gene rearrangement are worse, and more effective protocol is needed for this subtype patients.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Rearranjo Gênico , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Prognóstico , Receptores de Citocinas/genética , Receptores Purinérgicos P2Y/genética
7.
Biomaterials ; 272: 120765, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33780686

RESUMO

Ischemic stroke, and the consequent brain cell death, is a common cause of death and disability worldwide. Current treatments that primarily aim to relieve symptoms are relatively inefficient in achieving brain tissue regeneration and functional recovery, and thus novel therapeutic options are urgently needed. Although cell-based therapies have shown promise for treating the infarcted brain, a recurring challenge is the inadequate retention and engraftment of transplanted cells at the target tissue, thereby limiting the ultimate therapeutic efficacy. Here, we show that transplantation of preassembled three-dimensional (3D) spheroids of mesenchymal stem cells (MSCs) and vascular endothelial cells (ECs) results in significantly improved cell retention and survival compared with conventional mixed-cell suspensions. The transplanted 3D spheroids exhibit notable neuroprotective, proneurogenic, proangiogenic and anti-scarring potential as evidenced by clear extracellular matrix structure formation and paracrine factor expression and secretion; this ultimately results in increased structural and motor function recovery in the brain of an ischemic stroke mouse model. Therefore, transplantation of MSCs and ECs using the 3D cell spheroid configuration not only reduces cell loss during cell harvesting/administration but also enhances the resultant therapeutic benefit, thus providing important proof-of-concept for future clinical translation.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , AVC Isquêmico , Transplante de Células-Tronco Mesenquimais , Acidente Vascular Cerebral , Animais , Isquemia Encefálica/terapia , Células Endoteliais , Camundongos , Esferoides Celulares , Acidente Vascular Cerebral/terapia
8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(1): 49-55, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-33554796

RESUMO

OBJECTIVE: To investigate the clinical effect and safety of Chinese Children's Leukemia Group (CCLG)-ALL 2008 (high risk group) protocol in the treatment with childhood Mixed phenotype acute leukemia (MPAL). METHODS: The clinical data of 15 new diagnosed patients with MPAL treated in our hospital from January 2013 to December 2017 were retrospectively analyzed, and received CCLG-ALL 2008 (high risk group) protocol chemotherapy. RESULTS: One patient gave up treatment after diagnosed, and 14 children with MPAL after induction remission chemotherapy, 3 patients gave up, and 5 patients received consolidation chemotherapy, and 6 patients received allogeneic hematopoietic stem cell transplantation (allo-HSCT). The complete remission (CR) rate was 85.7% at d33 of induction remission chemotherapy. The serious adverse event and treatment-related mortality (TRM) rate was 71.4% and 14.3%, respectively. The recurrence rate was 21.4% and the median time of relapse was 12(9.7-18.4) months. Except for 4 patients who gave up treatment, the 5-year event-free survival (EFS) rate in the other 11 patients was (54.5±15.0)%. The 5 years EFS of 4 patients who received consolidation chemotherapy was significantly lower than the 6 patients who received allo-HSCT after CR (25.0%±21.7% vs 83.3%±15.2%, P=0.033). CONCLUSION: The CCLG-ALL2008 (for high-risk group) protocol in treatment of children with MPAL can get a high CR rate, but also with a high incidence of SAE. The patients received allo-HSCT after CR may have a good prognosis.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Criança , Intervalo Livre de Doença , Humanos , Fenótipo , Prognóstico , Indução de Remissão , Estudos Retrospectivos
9.
Phytomedicine ; 81: 153412, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33234364

RESUMO

BACKGROUND: Naringenin is naturally isolated from citrus fruits possessing many pharmacological activities. However, little is known about the effect of naringenin on nonalcoholic steatohepatitis (NASH) in the model of metabolic syndrome. PURPOSE: The present study is aimed to investigate the effect of naringenin on NASH in 12-mo-old male ApoE-/- mice and its possible underlying mechanism. METHODS: In vivo, 12-mo-old male ApoE-/- mice were administrated with naringenin by intragastric gavage for 12 weeks. At the end of experiment, the blood samples and liver tissues were collected. Metabolic parameters in serum, levels of triglyceride, cholesterol and hydroxyproline, activities of antioxidant enzymes, and content of inflammatory cytokines (TNF-α and IL-6) in liver were examined by corresponding assay kits. Pathological changes in liver were observed by hematoxylin-eosin, oil red O, masson's trichrome, picro-sirius red and senescence ß-galactosidase staining. Dihydroethidium was used for detection of reactive oxygen species (ROS). In vitro, AML-12 cells were treated with oleic acid in the presence or absence of naringenin for 24 h. Transfection of SIRT1 siRNA was also conducted in vitro. Lipid accumulation, cellular ROS generation, malondialdehyde content, antioxidant enzyme activities and secretion levels of TNF-α and IL-6 were examined. Both in vivo and in vitro, gene expressions were detected by real-time PCR or western blot. RESULTS: Naringenin administration improved metabolic parameters, suppressed hepatic steatosis, regulated expression of genes involved in lipid metabolism (FASN, SCD1, PPARα and CPT1α), reduced hepatic fibrosis and cell senescence, inhibited hepatic inflammation as evidenced by the decreased macrophage recruitment and content of TNF-α and IL-6, and reduced hepatic oxidative stress by suppressing ROS generation and normalizing activities of antioxidant enzymes. Notably, naringenin administration increased hepatic SIRT1 protein expression and activity along with the increased deacetylation of liver kinase B1 (LKB1), PGC1α and NF-κB. In vitro study, the benefits of naringenin on lipid accumulation, oxidative stress and inflammation were diminished by SIRT1 siRNA transfection. CONCLUSIONS: These results indicate that naringenin administration may be a potential curative therapy for NASH treatment and the activation of hepatic SIRT1-mediated signaling cascades is involved in its beneficial effects.


Assuntos
Flavanonas/farmacologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Sirtuína 1/metabolismo , Animais , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , NF-kappa B/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Proteínas Nucleares/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/metabolismo
10.
J Magn Reson ; 322: 106887, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33326918

RESUMO

One hallmark of modern nuclear magnetic resonance spectroscopy is the use of multi-dimensional correlation experiments typically with only spin Hamiltonians. However, spin systems may be affected by interactions and processes that are not controlled through the spin degree of freedom. This paper demonstrates a correlation spectroscopy between two different physical processes, one is NMR spin dynamics, and the other capillary drainage for the study of porous materials. We show that such a correlation experiment produces a joint capillary pressure (Pc) and NMR relaxation (T2) correlation function, Pc-T2 map that probes how pores are connected, an insight not available in conventional NMR or capillary experiments.

11.
Exp Ther Med ; 20(2): 901-909, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32742332

RESUMO

Neonatal vascular ophthalmopathy is a refractory ophthalmologic disease, and is a major cause of blindness. Occurrence of neonatal vascular ophthalmopathy may be associated with Paxillin, a cellular adhesion molecule which promotes the migration of endothelial cells and angiogenesis. To explore the role of PXN in corneal angiogenesis, human umbilical vein endothelial cells were divided into five groups: i) Control group; ii) Empty vector-transfected control group; iii) PXN knockdown group (shPXN group); iv) PXN-negative control (NC) group; and v) PXN over-expressed group (overExp group). PXN protein levels, migration and tube formation were assessed in the different experimental groups. Mice were divided into four groups: i) Control; ii) Model; iii) shPXN; and iv) overExp groups. Tube formation was significantly increased in the overExp group compared with the empty vector-transfected control group (P<0.01). Tube formation was significantly decreased in the shPXN group compared with the PXN-NC group (P<0.01). In mice, blood corpuscles were significantly decreased in the shPXN group. PXN promoted the migration of endothelial cells and corneal angiogenesis. The results of the present study suggest a role for PXN in corneal angiogenesis and provide a theoretical basis and potential target for the treatment of corneal angiogenesis.

12.
Atherosclerosis ; 305: 1-9, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32585463

RESUMO

BACKGROUND AND AIMS: Murine double minute-2 (MDM2) has been poorly studied in cardiovascular diseases. The aim of the present study was to determine the biological role of MDM2 in inflammation activation and mitochondrial damage in human aortic endothelial cells (HAECs) stimulated with oxidized low-density lipoprotein (ox-LDL). METHODS: The expression of MDM2 in the aortas of atherosclerotic mice was determined. An adenoviral vector for MDM2 overexpression and siRNA for MDM2 downregulation were constructed and used to transfect HAECs. The functional changes in HAECs stimulated by ox-LDL were observed. RESULTS: The protein expression of MDM2 was increased in atherosclerotic mice and ox-LDL-treated HAECs. In addition, ox-LDL-induced mRNA expression and secretion of TNF-α, IL-6 and IL-1ß were significantly decreased by MDM2 downregulation and increased by MDM2 overexpression, and activation of NF-κB and caspase-1 was involved in the activity of MDM2. The ox-LDL-induced mitochondrial damage, indicated as increase in mitochondrial ROS production, decrease in mitochondrial membrane potential and elevation of mitochondrial DNA release, was significantly reversed by MDM2 downregulation and worsened by MDM2 overexpression. The ox-LDL-induced activation of TLR9/NF-κB and NLRP3/caspase-1 pathway was inhibited by MDM2 downregulation and worsened by MDM2 overexpression. The aggravation caused by MDM2 overexpression was abolished by mito-TEMPO. Treatment with mito-TEMPO significantly reduced the increase in mRNA expression and secretion of TNF-α, IL-6 and IL-1ß induced by MDM2 overexpression in ox-LDL treated HAECs. CONCLUSIONS: These findings suggest that MDM2 contributes to ox-LDL-induced inflammation via regulating mitochondrial damage.


Assuntos
Células Endoteliais , Lipoproteínas LDL/efeitos adversos , Mitocôndrias/patologia , Proteínas Proto-Oncogênicas c-mdm2/fisiologia , Animais , Células Cultivadas , Humanos , Inflamação , Camundongos , NF-kappa B , Transfecção
13.
J Inorg Biochem ; 208: 111104, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32485635

RESUMO

Ruthenium complexes are expected to be new opportunities for the development of antitumor agents. Herein, four ruthenium polypyridyl complexes ([Ru(bpy)2(CAPIP)](ClO4)2 (Ru(II)-1, bpy = 2,2'-bipyridine; CAPIP = (E)-2-(2-(furan-2-yl)vinyl)-1H-imidazo[4,5-f][1,10]phenanthroline), [Ru(phen)2(CA-PIP)](ClO4)2 (Ru(II)-2, phen = 1,10-phenanthroline), [Ru(dmb)2(CAPIP)](ClO4)2 (Ru(II)-3, dmb = 4,4'-dimethyl-2,2'-bipyridine), [Ru(dmb)2(ETPIP)](ClO4)2 (Ru(II)-4, ETPIP = 2-(4-(thiophen-2-ylethynyl)phenyl)-1H-imidazo[4,5-f][1,10]phen-anthroline)) have been investigated as mitochondria-targeted antitumor metallodrugs. DNA binding studies indicated that target Ru(II) complexes interacts with CT DNA (calf thymus DNA) by an intercalative mode. Cytotoxicity assay results demonstrate that Ru(II) complexes show high cytotoxicity against A549 cells with low IC50 value of 23.6 ± 2.3, 20.1 ± 1.9, 22.7 ± 1.8 and 18.4 ± 2.3 µM, respectively. Flow cytometry and morphological analysis revealed that these Ru(II) complexes can induce apoptosis in A549 cells. Intracellular reactive oxygen species (ROS) and mitochondrial membrane potential were also investigated by ImageXpress Micro XLS system. The experimental results indicate that the reactive oxygen species in A549 cells increased significantly and mitochondrial membrane potential decreased obviously. In addition, colocalization studies shown these complexes could get to the cytoplasm through the cell membrane and accumulate in the mitochondria. Furthermore, Ru(II) complexes can effectively induces cell cycle arrest at the S phase in A549 cells. Finally, cell invasion assay and quantitative studies were also performed to investigate the mechanism of this process. All in together, this study suggested that these Ru(II) complexes could induce apoptosis in A549 cells through cell cycle arrest and ROS-mediated mitochondrial dysfunction pathway.


Assuntos
Antineoplásicos , Complexos de Coordenação , Neoplasias , Piridinas , Rutênio , Células A549 , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Complexos de Coordenação/farmacocinética , Complexos de Coordenação/farmacologia , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Piridinas/química , Piridinas/farmacocinética , Piridinas/farmacologia , Rutênio/química , Rutênio/farmacocinética , Rutênio/farmacologia
14.
Prostaglandins Other Lipid Mediat ; 150: 106464, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32464175

RESUMO

Elevated inflammation is commonly observed in depression, but whether this association is causal is not determined. Our previous basic research indicated that Dl-3-n-butylphthalide (NBP) possessed an anti-inflammatory effect. Additional recent evidence consistently suggests that depression is associated with lipid metabolism. Therefore, our study performed an untargeted lipidomics approach of ultra-performance liquid chromatography coupled with mass spectrometry (UPLC-MS) to reveal the potential discriminating lipid profile of the hippocampus for NBP involvement in lipopolysaccharide (LPS)-induced depression. Male Sprague-Dawley(SD) rats were randomly allocated to one of three groups (n = 6): control, LPS-induced model of depression (LPS), or NBP involvement in the LPS-induced model of depression (LPS + NBP). Statistical analysis was used to identify differential hippocampus lipids in the LPS, NBP + LPS, and control groups. Our study demonstrated that most of the differentially expressed lipid metabolites were involved in glycerophospholipid metabolism, sphingolipid metabolism, glycerolipid metabolism, and glycosylphosphatidylinositol(GPI)-anchor biosynthesis, which may partially account for the pathophysiological process of depression. However, more pre-clinical and clinical evidence is warranted to determine the extent and consistency of the role of NBP and further elucidate the pathophysiological mechanisms underlying inflammation-induced depression.

15.
Connect Tissue Res ; : 1-9, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32308055

RESUMO

Purpose: Even though differences between deciduous and permanent dentin have been widely studied, their dynamic mechanical behavior has never been compared. The objective of the present study was to quantify the differences between deciduous and permanent dentin under cyclic mechanical loading, which is similar to masticatory stress.Materials and Methods: Deciduous and permanent teeth, respectively from children (9 ~ 12 years old) and young people (18 ~ 25 years old), were wet-sectioned perpendicular to the longitudinal axis and the central specimens of coronal dentin were evaluated by nanoscopic dynamic mechanical analysis (nanoDMA).Results: The average storage, loss, and complex moduli, as well as the hardness of deciduous dentin were significantly (p < 0.05) lower than those of permanent dentin. Moreover, the tan δ value of permanent dentin was significantly (p < 0.05) lower than that of deciduous dentin across the loading frequency range, indicating that viscoelastic behavior and loss of elastic energy were significantly reduced in the stiffer permanent dentin. All the nanoDMA responses showed a significant influence of the dynamic loading frequency (p < 0.05): Both deciduous and permanent dentin showed reduced viscoelasticty with increased loading frequencies.Conclusions: Compared with deciduous dentin, permanent dentin exhibits higher stiffness with reduced energy loss during deformation, and therefore superior mechanical characteristics for the mastication process.

16.
Sci Total Environ ; 726: 138392, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32334351

RESUMO

The aim of this study was to investigate the microbial characteristics and the structural role of exDNA in different size AGSs. Metagenomic results showed that exDNA has a significantly lower GC content, ~46.0%, than the ~65.0% GC of intracellular DNA (inDNA). Taxonomic predictions showed most of the reads from the exDNA that could be taxonomically assigned were from members of the phyla Bacteroidetes (55.0-64.2% of the total exDNA reads). Assigned inDNA reads were mainly from Proteobacteria (50.9-57.8%) or Actinobacteria (18.0-28.0%). Reads mapping showed that exDNA read depths were similar across all predicted open reading frames from assembled genomes that were assigned as Bacteroidetes which is consistent with cell lysis as a source of exDNA. Enrichment of CRISPR-CAS proteins in exDNA reads and CRISPR spacers in Bacteroidetes associated draft genomes suggested that bacteriophage infection may be an important cause of lysis of these cells. A critical role for this exDNA was found using DNase I digestion experiments which showed that the exDNA was vital for the structural stability of relatively small sized AGS but not for the larger sized AGS. The characteristics of exDNA in AGSs revealed in this work provide a new perspective on AGS components and structural stability.


Assuntos
Bacteriófagos , Esgotos , Bactérias , Reatores Biológicos , DNA , Metagenoma
17.
Int J Artif Organs ; : 391398820908877, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32191150

RESUMO

OBJECTIVE: This study aims to evaluate the clinical efficacy and visual function prognosis of macular hole retinal detachment treatment for high myopia by inverting the internal limiting membrane to overlay the macular hole with the assistance of perfluorocarbon liquids. METHODS: A total of 55 high myopia patients, who received macular hole retinal detachment treatment from 2013 to 2016, were included in this study. Among these patients, 38 patients were assigned to the first group and 17 patients (perfluorocarbon liquids) were assigned to the second group. The second group was further divided into two subgroups, according to the overlaying layer number of the internal limiting membrane valve: A group (multiple layers) and B group (single layer). RESULTS: The success rate of the internal limiting membrane inversion and overlaying on the macular hole was 23.68% and 100% in the first and second group, respectively. The differences in macular hole closing rate and postoperative best-corrected visual acuity between these two groups were statistically significant (p < 0.05). Furthermore, the differences in macular morphology recovery between the A and B groups were also statistically significant (p = 0.004 < 0.05). CONCLUSION: Perfluorocarbon liquids play a positive role in the operation process of the internal limiting membrane.

18.
World J Clin Cases ; 8(5): 980-985, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32190636

RESUMO

BACKGROUND: Congenital anomalous retinal artery is rare and does not typically affect visual acuity. However, an abnormal artery that passes through and supplies blood to the macular area complicated with branch retinal artery occlusion may negatively impact visual acuity. This study reports an unusual case of anomalous retinal artery combined with retinal artery occlusion. CASE SUMMARY: A 52-year-old male presented with severely reduced vision in the right eye. The fundus examination revealed an anomalous artery, extending from the superior temporal arcade and crossing the macula into the inferior temporal quadrant. The anomalous artery was partially occluded, with a narrowed lumen. A cherry-red spot was observed with whitening of the macular area, suggesting macular edema. Fundus fluorescein angiography revealed disc leakage and a delayed filling time. Optical coherence tomography revealed increased thickness of the neuroretina and underlying layers. The patient was treated with vessel dilation, hyperbaric oxygen, ocular massage, and thrombolytics. Visual acuity of the right eye subsequently improved to 20/200 from hand motion at 4 cm. This improvement in visual acuity persisted when the patient was examined at the 1-mo follow-up visit. The patient was subsequently followed via telephone interview. The information provided via interview indicated that visual acuity in the affected eye was stable up to 6 years from the time of the initial presentation. However, after 3 additional years, the patient was diagnosed with neovascular glaucoma in the right eye, which was subsequently enucleated. CONCLUSION: Although congenital retinal vascular anomaly, including anomalous retinal artery, rarely affects vision, when complicated with branch retinal artery occlusion, the abnormal artery that supplies the macula may severely reduce visual acuity.

19.
Biochem Pharmacol ; 175: 113927, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32217100

RESUMO

Dihydromyricetin (DMY) is the most abundant flavonoid in Ampelopsis grossedentata possessing many pharmacological activities. But less is known about its protective effect against nonalcoholic steatohepatitis (NASH) in the context of metabolic syndrome. The present study is aimed to evaluate the pharmacological effects of DMY on NASH induced by feeding a high fat diet to 12-mo-old male LDLr-/- mice for 12 weeks and its molecular mode of action. At the end of the experiment, the blood samples and liver tissues of mice were collected for analysis. The results showed that DMY treatment improved the steatosis, inflammation and fibrosis which are three main aspects of NASH and some of the metabolic basal characteristics. The underlying mechanisms include regulating key regulators of lipid metabolism, oxidative stress, inflammation and fibrosis. Notably, DMY treatment increased hepatic sirtuin 1 (SIRT1) activity and protein expression. DMY also enhanced deacetylation of liver kinase B1 (LKB1) and nuclear transcription factor kappa B (NF-kB). Furthermore, in cultured hepatocyte cells, the benefits of DMY on lipid accumulation, oxidative stress and inflammation as well as the above related genes were abrogated in hepatocytes transfected with SIRT1 siRNA. These results suggest that modulation of SIRT1-mediated signaling cascades contributes to the amelioration of NASH by DMY and DMY may serve as a potentialtherapeuticcandidate for human NASH.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Flavonóis/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Receptores de LDL/deficiência , Sirtuína 1/metabolismo , Fatores Etários , Animais , Linhagem Celular Transformada , Flavonóis/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/etiologia
20.
NMR Biomed ; 33(12): e4238, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32012371

RESUMO

Multidimensional MR experiments of relaxation and diffusion have been successful for material characterization and have attracted attention recently for biomedical applications. However, such experiments typically require many scans of data acquisition and are time-consuming. This work discusses a method for systematic optimization of the pulse-sequence parameters to obtain optimal resolution within the experimental conditions, such as the number of acquisitions. Other optimization goals can also be incorporated in this framework.

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