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1.
J Esthet Restor Dent ; 35(2): 303-308, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36573304

RESUMO

OBJECTIVE: This study aimed to explore the influence of smile esthetics on the quality of life in a Han Chinese population. METHODS: A total of 110 Han Chinese volunteers (52 males and 58 females, mean age 26.7 years) were recruited, and frontal images of their smiles were collected. A photoediting program was used to evaluate the following components of smile esthetics: the buccal corridor ratios, the angle between the interpupillary and commissural lines, the number of visible teeth, and width-to-length ratios of the maxillary central incisors. Oral health-related quality of life (OHRQoL) in these volunteers was evaluated using the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) and Oral Health Impact Profile-14 (OHIP-14). Statistical analyses were performed by using Pearson's correlations and multiple linear regression (α = 0.05). RESULTS: Compared to males, females scored higher on psychological impact (p = 0.017). Moreover, the number of visible teeth had a significant effect on social impact, psychological impact and esthetic concern (all p < 0.05). However, the buccal corridor ratios, the angle between the interpupillary and commissural lines, and the width-to-length ratios of the maxillary central incisor did not correlate with the OHRQoL (all p > 0.05). CONCLUSIONS: The number of visible teeth significantly influenced the quality of life in a Han Chinese population. Smile esthetics had a significantly greater psychological impact on females than males. CLINICAL SIGNIFICANCE: This study highlights the effects of smile esthetics on the quality of life in a Han Chinese population. Female patients may raise more esthetic concerns in clinical practice.


Assuntos
Estética Dentária , Qualidade de Vida , Sorriso , Adulto , Feminino , Humanos , Masculino , População do Leste Asiático , Incisivo/anatomia & histologia
2.
Am J Dent ; 35(4): 178-184, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35986932

RESUMO

PURPOSE: To do a systematic review and meta-analysis to determine whether laser treatment affects the bond strength of resin composites to recently bleached enamel. METHODS: This report follows the Preferred Reporting Items for Systematic Reviews and Qualitative Analyses (PRISMA) statement. Medline via PubMed, Embase, Web of Science, and the Cochrane Library databases were searched with no limits on publication year. Two reviewers independently screened all titles and abstracts to perform the study selection, data extraction, and risk-of-bias assessments. A random-effects meta-analysis model was performed using Review Manager software (version 5.3, Cochrane Collaboration). RESULTS: From the 93 records identified, seven articles that met all the inclusion criteria were included in the systematic review, and six studies were included in the meta-analysis. The overall results showed a statistically significant difference in bond strength between the control group and laser-treated group (P= 0.04; mean difference: 5.27; 95% confidence interval: 0.28 to 10.27), favoring the laser-treated group. Subgroup analyses revealed that the tooth source (bovine or human teeth) contributed to the effect of laser treatment on the bleached enamel. CLINICAL SIGNIFICANCE: Laser treatment may increase the bond strength of resin composites to recently bleached enamel. Pretreatment with a laser, preferably with Nd:YAG (1 W, frequency of 10 Hz, irradiation time of 60 seconds) or CO2 lasers (0.5 W, frequency of 10 Hz, irradiation time of 60 seconds), may be recommended to restore the bond strength of recently bleached enamel.


Assuntos
Colagem Dentária , Lasers de Estado Sólido , Animais , Bovinos , Resinas Compostas/química , Colagem Dentária/métodos , Esmalte Dentário , Humanos , Lasers de Estado Sólido/uso terapêutico
3.
J Prosthet Dent ; 123(6): 845-849, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31672423

RESUMO

STATEMENT OF PROBLEM: Various components of smile esthetics have been evaluated. However, whether these components affect smile esthetics in Han Chinese celebrities, dentists, and dental students is unknown. PURPOSE: The purpose of this study was to evaluate the smile esthetics of celebrities, dentists, and dental students in a Han Chinese population. MATERIAL AND METHODS: Frontal images of smiles were obtained from the Internet for the celebrity group, while images of dentists and dental students were collected for the dentist and dental student groups. The buccal and posterior corridor ratios, the alignment discrepancy between the commissural and interpupillary lines, the number of teeth revealed, the width ratio relative to the golden proportion, and the width-to-length ratios of maxillary anterior teeth were calculated by using a photo-editing software program. Statistical analysis was performed by using 2-way ANOVA and the Tukey HSD test (α=.05). RESULTS: Eligible images were obtained for 81 celebrities, 83 dentists, and 78 dental students. The celebrities were found to have the highest buccal and posterior corridor ratios and reveal the least teeth in the smile among the 3 groups (all P<.001). The alignment discrepancy for celebrities was significantly less than that for dental students (P=.025). Moreover, the absolute difference of width ratios from the golden proportion was significantly different from 0 for all groups (all P<.001). CONCLUSIONS: Significant differences were found in the smiles of Han Chinese celebrities, dentists, and dental students in regard to the buccal and posterior corridor ratios, the alignment discrepancy between the commissural and interpupillary lines, and the number of teeth revealed. Chinese celebrities tended to have a smile that displays to the second premolar, with a medium buccal corridor width.


Assuntos
Estudantes de Odontologia , Dente , Odontólogos , Estética Dentária , Humanos , Sorriso
4.
BMC Oral Health ; 20(1): 218, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32758296

RESUMO

BACKGROUND: The bond strength of resin composites to dentin was reported to be related to either the remaining dentin thickness (RDT) or bleaching treatment. However, information is limited regarding the effects of RDT on the bond strength of bleached dentin. The present study aimed to investigate the effects of RDT on the microshear bond strength (µSBS) of resin cement to bleached dentin. METHODS: A total of 120 dentin specimens were prepared and randomly divided into 2 groups: a bleaching group (group B) and a control group (group C). Hydrogen peroxide with a concentration of 35% (Ultradent, USA) was applied on the dentin surface for 2 × 1 d for group B, while no bleaching treatment was performed for group C. After the treatment, the specimens were finished and polished to obtain different RDTs (2, 1, and 0.5 mm) and divided into 3 groups of 20 specimens each. The bonding procedure was performed using Panavia V5 (Kuraray, Japan) with a bonding area of 0.785 mm2. For each group, half of the specimens were subjected to 5000 thermal cycles (subgroup T), while the other half did not receive thermocycling (subgroup N) (n = 10). The specimens were then subjected to the µSBS test using a universal testing machine. Data were analyzed by a three-way analysis of variance (α = 0.05). The fracture modes of the specimens were confirmed with a measuring microscope. Representative specimens with different fracture modes were observed with scanning electron microscopy (SEM). RESULTS: The µSBS values were significantly affected by bleaching treatment (p < 0.001), whereas no significant effect was observed for thermocycling (p = 0.293). In terms of RDT, a significantly different µSBS value was found among the subgroups with different RDTs in group C (p = 0.003). However, the RDT did not significantly affect the µSBS values of bleached dentin in group B (p = 0.779). The µSBS values were significantly lower in group B than in group C (p < 0.001). A higher percentage of adhesive failure was observed in group B than in group C. CONCLUSION: Based on the present findings, it can be concluded that the RDT did not affect the bond strength of resin cement to bleached dentin. CLINICAL SIGNIFICANCE: Since RDT did not affect the bond strength of resin cement to bleached dentin, bonding procedures should not be performed immediately after intracoronal bleaching, even if the dentin is planned to be removed due to a tooth preparation process.


Assuntos
Colagem Dentária , Clareamento Dental , Resinas Compostas , Dentina , Japão , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento
5.
J Cell Sci ; 130(5): 1003-1015, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28082423

RESUMO

GFP-binding protein (or GBP) has been recently developed in various systems and organisms as an efficient tool to purify GFP-fusion proteins. Due to the high affinity between GBP and GFP or GFP variants, this GBP-based approach is also ideally suited to alter the localization of functional proteins in live cells. In order to facilitate the wide use of the GBP-targeting approach in the fission yeast Schizosaccharomyces pombe, we developed a set of pFA6a-, pJK148- and pUC119-based vectors containing GBP- or GBP-mCherry-coding sequences and variants of inducible nmt1 or constitutive adh1 promoters that result in different levels of expression. The GBP or GBP-mCherry fragments can serve as cassettes for N- or C-terminal genomic tagging of genes of interest. We illustrated the application of these vectors in the construction of yeast strains with Dma1 or Cdc7 tagged with GBP-mCherry and efficient targeting of Dma1- or Cdc7-GBP-mCherry to the spindle pole body by Sid4-GFP. This series of vectors should help to facilitate the application of the GBP-targeting approach in manipulating protein localization and the analysis of gene function in fission yeast, at the level of single genes, as well as at a systematic scale.


Assuntos
Técnicas Citológicas/métodos , Proteínas de Fluorescência Verde/metabolismo , Schizosaccharomyces/metabolismo , Sequência de Bases , Genes Reporter , Vetores Genéticos/metabolismo , Luciferases/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica , Transporte Proteico , Proteínas Recombinantes de Fusão/metabolismo , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismo , Corpos Polares do Fuso/metabolismo
6.
J Prosthet Dent ; 122(1): 22-30.e5, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30782459

RESUMO

STATEMENT OF PROBLEM: Different finish-line designs have been advocated for tooth preparations of ceramic crowns. However, scientific evidence is lacking to help clinicians make a proper selection. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the effects of finish-line designs on the marginal and internal adaptations of ceramic crowns. MATERIAL AND METHODS: This report follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The literature search was conducted in MEDLINE via the PubMed, Embase, and Web of Science databases with no publication year or language limits. In vitro studies comparing the marginal and internal adaptations of ceramic crowns with rounded shoulder and chamfer finish lines were included in the meta-analysis. RESULTS: Sixteen studies were included in the qualitative synthesis and meta-analyses. Statistical analyses were conducted using the Review Manager Software. Meta-analyses were performed with random-effects models (α=.05). Ceramic crowns with rounded shoulders exhibited significantly better marginal adaptation than those with chamfers (P<.001; mean difference=-7.8; 95% confidence interval=-11.6 to -4.1). Moreover, ceramic crowns with chamfers exhibited significantly better internal adaptation than those with rounded shoulders (P=.020; mean difference=35.0; 95% confidence interval=6.5 to 63.5). CONCLUSIONS: The difference in marginal adaptation of ceramic crowns using 2 finish-line designs was small, and the clinical significance was low, whereas the results of internal adaptation favored the chamfer finish line.


Assuntos
Coroas , Adaptação Marginal Dentária , Cerâmica , Porcelana Dentária , Planejamento de Prótese Dentária , Preparo Prostodôntico do Dente
7.
Adv Exp Med Biol ; 1077: 285-306, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30357694

RESUMO

In order to develop and commercialize for the regenerative medicinal products, smart biomaterials with biocompatibility must be needed. In this chapter, we introduce collagen and hyaluronic acid (HA) as extracellular matrix as well as deal with the molecular mechanism as microenvironment, mechanistic effects, and gene expression. Application of collagen and HA have been reviewed in the area of orthopedics, orthopedics, ophthalmology, dermatology and plastic surgery. Finally, the ongoing and commercial products of collagen and HA for regenerative medicine have been introduced.


Assuntos
Materiais Biocompatíveis , Colágeno/uso terapêutico , Ácido Hialurônico/uso terapêutico , Medicina Regenerativa/tendências , Matriz Extracelular , Humanos
8.
J Org Chem ; 82(23): 12849-12856, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29065266

RESUMO

A protecting-group-free synthetic approach to 1-phenylisoquinolin-4-ols was developed by the intramolecular thermal cyclization of methyl 2-[(diphenylmethylidene)amino]acetates. R1 and R2 substituents were found to affect the required reaction temperatures, time, and yields of the cyclized products. The reactivity of the Schiff bases increased upon introduction of α-benzoyl and α-ester groups (R2). The cyclization yield also depended on the position of the R1 substituents on the phenyl groups.

9.
Cell Physiol Biochem ; 31(4-5): 625-37, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23652646

RESUMO

AIMS: To investigate alterations in protein expression associated with deep brain stimulation (DBS) in an attempt to elucidate possible mechanisms of action . METHODS: Cerebrospinal fluid (CSF), obtained from six Parkinson's disease (PD) patients (pre- and post-DBS) and from six normal healthy controls, was studied for differentially expressed proteins. 2-D DIGE, in combination with MALDI-TOF and TOF-TOF Mass Spectrometry (MS) or ESI-MS, was used to identify the changed proteins (3 PD patients and 3 controls). Selected proteins were further studied using western blotting (6 PD patients and 6 controls). RESULTS: Twenty-one proteins were identified after MS and protein database interrogation. Apart from apolipoprotein A-I (apoA-I), the expression levels of complement C4 (C4), IgA, tetranectin, and extracellular superoxide dismutase (EC-SOD), detected by western blotting, correlated well with the 2-D DIGE results. In the follow-up period, the expression levels of C4, apoA-I and IgA were stable whereas EC-SOD and tetranectin were significantly elevated. In addition, when DBS was ceased in one patient due to a suicide attempt, the levels of EC-SOD and tetranectin significantly decreased. CONCLUSION: Our preliminary results suggest that variations in the expression levels of EC-SOD and tetranectin in CSF is related to DBS.


Assuntos
Eletroforese em Gel Bidimensional , Doença de Parkinson/terapia , Proteoma/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Idoso , Bases de Dados de Proteínas , Estimulação Encefálica Profunda , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/líquido cefalorraquidiano , Proteômica
10.
Acta Pharmacol Sin ; 34(4): 473-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23474709

RESUMO

AIM: To investigate whether multidrug resistance-associated protein 1 (MRP1) was responsible for drug resistence in refractory epilepsy in amygdale kindling rats. METHODS: Rat amygdale kindling was used as a model of refractory epilepsy. The expression of MRP1 mRNA and protein in the brains was examined using RT-PCR and Western blot. MRP1-positive cells in the cortex and hippocampus were studied with immunohistochemical staining. The rats were intraperitoneally injected with phenytoin (50 mg/kg) or carbamazepine (20 mg/kg), and their concentrations in the cortical extracellular fluid were measured using microdialysis and HPLC. Probenecid, a MRP1 inhibitor (40 mmol/L, 50 µL) was administered through an inflow tube into the cortex 30 min before injection of the antiepileptic drugs. RESULTS: The expression of MRP1 mRNA and protein was significantly up-regulated in the cortex and hippocampus in amygdale kindling rats compared with the control group. Furthermore, the number of MRP1-positive cells in the cortex and hippocampus was also significantly increased in amygdale kindling rats. Microdialysis studies showed that the concentrations of phenytoin and carbamazepine in the cortical extracellular fluid were significantly decreased in amygdale kindling rats. Pre-administration of probenecid could restore the concentrations back to their control levels. CONCLUSION: Up-regulation of MRP1 is responsible for the resistance of brain cells to antiepileptic drugs in the amygdale kindling rats.


Assuntos
Anticonvulsivantes/farmacologia , Córtex Cerebral/metabolismo , Líquido Extracelular/metabolismo , Excitação Neurológica/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Animais , Anticonvulsivantes/farmacocinética , Carbamazepina/farmacologia , Córtex Cerebral/efeitos dos fármacos , Epilepsia/tratamento farmacológico , Epilepsia/genética , Epilepsia/metabolismo , Líquido Extracelular/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Excitação Neurológica/efeitos dos fármacos , Excitação Neurológica/genética , Masculino , Microdiálise/métodos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Fenitoína/farmacologia , RNA Mensageiro/genética , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Regulação para Cima/efeitos dos fármacos
11.
Am J Cancer Res ; 13(4): 1329-1346, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168338

RESUMO

Leydig cell tumor is the most frequent non-germ cell tumors of testis. The biggest challenge of using radiotherapy to treat testicular cancer is in effectively killing cancer cells and maintaining reproductive function after treatment. Our recently published article showed that cordycepin could enhance radiosensitivity to induce mouse Leydig tumor cell apoptosis by inducing cell cycle arrest, caspase pathway and endoplasmic reticulum (ER) stress. In the present study, the potency and mechanism of a previous combination treatment protocol on reactive oxygen species (ROS) induction and DNA damage were further investigated. Our results reveal that 25 µM cordycepin plus 4 Gy radiation leads to ROS accumulation accompanied by a decrease in heme oxygenase (HO)-1 protein expression in MA-10 mouse Leydig tumor cells. Subsequently, pronounced DNA damage with phosphorylated H2A histone family member X (γ-H2AX) increase and activation of DNA damage-related signaling pathways including double and single stranded break-induced ataxia telangiectasia mutated (ATM)/checkpoint kinase (Chk)2 and ataxia telangiectasia mutated and Rad3 related (ATR)/Chk1 signaling axes were identified. p53-dependent pathway was then initiated ultimately leading to cell death. Preincubated with free radical scavenger, N-acetylcysteine (NAC), down-regulated γ-H2AX expression in treated cells and partially reduced cell death, indicating that ROS overproduction is involved in combination treatment-induced DNA damage. Furthermore, the combination treatment effectively inhibited tumor growth as reflected in the reduction of tumor volume, size and weight, and high expression level of γ-H2AX in tumor tissue in vivo, suggesting that the combination treatment inhibited tumor growth via causing DNA damage in MA-10 cells. In summary, these results expound that the combination treatment of cordycepin and radiation induces MA-10 mouse Leydig tumor cell death through ROS accumulation and DNA damage. This finding can serve as a reference guideline for future clinical therapy of testicular cancer and provide potential targets for anti-cancer drug design.

12.
Med Sci Monit ; 18(7): RA118-25, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22739749

RESUMO

Recent studies substantiate a model of the tunica albuginea of the corpora cavernosa as a bi-layered structure with a 360° complete inner circular layer and a 300° incomplete outer longitudinal coat spanning from the bulbospongiosus and ischiocavernosus proximally and extending continuously into the distal ligament within the glans penis. The anatomical location and histology of the distal ligament invites convincing parallels with the quadrupedal os penis and therefore constitutes potential evidence of the evolutionary process. In the corpora cavernosa, a chamber design is responsible for facilitating rigid erections. For investigating its venous factors exclusively, hemodynamic studies have been performed on both fresh and defrosted human male cadavers. In each case, a rigid erection was unequivocally attainable following venous removal. This clearly has significant ramifications in relation to penile venous surgery and its role in treating impotent patients. One deep dorsal vein, 2 cavernosal veins and 2 pairs of para-arterial veins (as opposed to 1 single vein) are situated between Buck's fascia and the tunica albuginea. These newfound insights into penile tunical, venous anatomy and erection physiology were inspired by and, in turn, enhance clinical applications routinely encountered by physicians and surgeons, such as penile morphological reconstruction, penile implantation and penile venous surgery.


Assuntos
Evolução Biológica , Mamíferos/anatomia & histologia , Mamíferos/fisiologia , Ereção Peniana/fisiologia , Pênis/anatomia & histologia , Pênis/fisiologia , Médicos , Animais , Disfunção Erétil/fisiopatologia , Humanos , Masculino , Pênis/cirurgia
13.
Oncol Lett ; 22(4): 705, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34457060

RESUMO

It has been reported that paclitaxel activates cell cycle arrest and increases caspase protein expression to induce apoptosis in head and neck squamous cell carcinoma (HNSCC) cell lines. However, the potential signaling pathway regulating this apoptotic phenomenon remains unclear. The present study used OEC-M1 cells to investigate the underlying molecular mechanism of paclitaxel-induced apoptosis. Following treatment with paclitaxel, cell viability was assessed via the MTT assay. Necrosis, apoptosis, cell cycle and mitochondrial membrane potential (∆Ψm) were analyzed via flow cytometric analyses, respectively. Western blot analysis was performed to detect the expression levels of proteins associated with the MAPK and caspase signaling pathways. The results demonstrated that low-dose paclitaxel (50 nM) induced apoptosis but not necrosis in HNSCC cells. In addition, paclitaxel activated the c-Jun N-terminal kinase (JNK), but not extracellular signal-regulated kinase or p38 mitogen-activated protein kinase. The paclitaxel-activated JNK contributed to paclitaxel-induced apoptosis, activation of caspase-3, -6, -7, -8 and -9, and reduction of ∆Ψm. In addition, caspase-8 and -9 inhibitors, respectively, significantly decreased paclitaxel-induced apoptosis. Notably, Bid was truncated following treatment with paclitaxel. Taken together, the results of the present study suggest that paclitaxel-activated JNK is required for caspase activation and loss of ∆Ψm, which results in apoptosis of HNSCC cells. These results may provide mechanistic basis for designing more effective paclitaxel-combining regimens to treat HNSCC.

14.
J Dent ; 95: 103318, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32169479

RESUMO

OBJECTIVES: To evaluate the short-term effects of stain-causing beverages on the effectiveness of in-office tooth bleaching. METHODS: Participants were recruited and randomly divided into 3 groups based on beverages used for rinsing during and after the bleaching procedure: group N (tap water, control group), group C (coffee), and group T (tea). Participants were instructed to rinse with the respective solutions for 30 s, 4 times daily for 4 weeks. All participants received two in-office bleaching treatment sessions with 40 % hydrogen peroxide (Opalescence BOOST PF 40 %, Ultradent); the sessions were separated by a 1-week interval. Tooth colour was assessed using a spectrophotometer (Easyshade, Vita ZahnFabrik) before the bleaching procedure (T0), immediately after the first session of bleaching (T1), immediately after the second session of bleaching (T2), as well as one week (T3) and three weeks after (T4) the end of bleaching. Tooth sensitivity (TS) was ranked using a numerical rating scale (NRS) and a visual analogue scale (VAS) at different time points. RESULTS: No significant difference in the whiteness index (W), △E, △a* and △b* values among the 3 groups was observed at any time interval (P for all > 0.05). At T4, the △L* value in group C was significantly lower than that in groups T and N (P = 0.022 and P = 0.001, respectively), though no significant difference in △L* values was observed among the 3 groups at T1 (P = 0.402), T2 (P = 0.643) and T3 (P = 0.177). Additionally, no significant difference was found in the TS values among the 3 groups at any of the evaluation time points (P for all > 0.05). CONCLUSIONS: Exposure to coffee or tea during the bleaching treatment period did not affect the effectiveness of the treatment. However, exposure to coffee after the bleaching treatment did affect the effectiveness of the treatment. Exposure to stain-causing beverages did not affect the bleaching-induced TS (ClinicalTrials.gov Identifier: NCT03933527). CLINICAL SIGNIFICANCE: The consumption of coffee or tea during tooth bleaching may not interfere with the colour change produced by the treatment. However, clinicians should advise their patients to refrain from, at least to some extent, consuming coffee after the bleaching procedure to maintain the effectiveness of the treatment.


Assuntos
Bebidas , Sensibilidade da Dentina , Clareadores Dentários , Clareamento Dental , Corantes , Humanos , Peróxido de Hidrogênio
15.
J Hazard Mater ; 397: 122431, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32438244

RESUMO

The structural and chemical stability of UiO-66-NH2 and its simulated solar irradiation responsive characteristic make it a suitable metal-organic framework (MOF) candidate as photocatalytic material. Platinum nanoparticles (Pt NPs) are typically immobilized in MOF to enhance the photocatalytic efficiency. However, introducing high metal content in MOF with high dispersion is still challenging using conventional methods. In this paper, we present de novo synthesis of Pt@UiO-66-NH2, which can reach a highest metal content of 16 wt% with an average nanoparticle size of around 2 nm as confirmed by ICP-MS analysis and TEM images. The presence of benzoic acid plays multiple important roles in Pt@UiO-66-NH2 formation, including binding formation with Zr clusters, facilitating Pt dispersion, and being a modulator in MOF construction. In addition, the Pt@UiO-66-NH2 is fabricated on the α-Al2O3 substrate as a photocatalytic membrane reactor (PMR) for phenol degradation, which shows over 70 % removal efficiency under light irradiation and H2O2 addition. The recycle test shows that the PMR can maintain high catalytic efficiency. The facile de novo synthesis method proposed in this study enables effective immobilization of high metal content in MOF, and construction of membrane-based photocatalyst for scale-up application.

16.
Oncol Lett ; 18(1): 944-954, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31289573

RESUMO

The incidence of testicular cancer is increasing worldwide. Leydig cell tumors represent one type of sex cord-stromal testis malignancy, which tend to respond unfavorably to chemotherapies. Identifying more efficient treatment strategies is therefore crucial for patients. The present study aimed to investigate the apoptotic effects of arsenic compounds and their underlying mechanisms. The results indicated that sodium arsenite and dimethylarsenic acid induced apoptosis of the murine Leydig tumor cell line, MA-10. These apoptotic effects were characterized morphologically by membrane blebbing and cell detachment assays, biochemically using a cell viability assay, and cytologically by flow cytometry analysis. Western blotting demonstrated that caspases-3, -8 and -9, and poly(ADP-ribose) polymerase protein levels were increased compared with untreated MA-10 cells; however, the caspase inhibitor, Z-VAD-fmk, reversed these effects. In conclusion, the present study has shown that sodium arsenite and dimethylarsenic acid may activate the intrinsic and extrinsic caspase pathways, and induce MA-10 cell apoptosis. These results suggest that sodium arsenite and dimethylarsenic acid may represent novel approaches to treat clinically unmanageable forms of testicular cancer.

17.
Med Eng Phys ; 30(8): 1020-3, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18006357

RESUMO

Pulmonary ventilation of patients implanted with a nasogastric tube is often difficult for medical personnel, since air leakage through the facemask and nasogastric tube interface is inevitable. Here we designed and tested a special facemask to improve ventilation in these patients. Forty patients with ASA class I-II were randomly assigned to two groups (study and control, n=20 each patients/group). All patients received abdominal surgery with a nasogastric tube inserted before operation. Before induction arterial lines were set up under local anesthesia. Blood gas samples were taken before, during and 1 min after endotracheal intubation. Haemodynamic data were obtained from the artery lines. Inspiratory and expiratory tidal volumes were measured by the Wright's spirometer connected to the anesthesia machine. For induction we used the new mask for the study group and the conventional mask for the controls. Blood gas values and leakage volumes were compared statistically (unpaired t-test, significant levels set at p<0.05). Air leakage was significantly reduced under the new mask with a concomitant improvement in PaO(2). There was however no change in terms of haemodynamic and PaCO(2) between the two groups. Results indicated the advantage of the new mask for patients with nasogastric tubes.


Assuntos
Intubação Gastrointestinal/métodos , Máscaras , Respiração Artificial/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
18.
IEEE J Biomed Health Inform ; 22(2): 545-551, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28141539

RESUMO

For better treatment outcomes, dentists usually use a set of parameters for orthodontic evaluation. In this study, a new method is proposed to assist dentists in obtaining reliable assessment of these parameters. The proposed method is based on dental panoramic radiographs and can be divided into four stages: image preprocessing, model training, tooth segmentation, and assessment of orthodontic parameters. The image is first normalized and enhanced. Then, the model training stage consists of shape and image model training, energy function training, and weight training. Next, we automatically segment the tooth contours in an energy-minimized manner. Finally, the automatic assessment of orthodontic parameters is carried out. The experimental results show that the average of absolute distance, the Dice similarity coefficient, and the average qualitative score ranged between 4.17 and 6.03, 0.87 and 0.90, as well as 2.58 and 3.12, respectively. The orthodontic assessment also is close to the evaluation of orthodontists. It has been shown that the proposed method can obtain accurate and consistent measurement in helping dentists to obtain an objective treatment evaluation.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Modelos Dentários , Radiografia Panorâmica/métodos , Adolescente , Adulto , Algoritmos , Criança , Humanos , Má Oclusão/diagnóstico por imagem , Adulto Jovem
19.
J Food Drug Anal ; 25(1): 197-205, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28911537

RESUMO

Cordyceps sinensis has various biological and pharmacological functions, and it has been claimed as a tonic supplement for sexual and reproductive dysfunctions for a long time in oriental society. In this article, the in vitro and in vivo effects of C. sinensis and cordycepin on mouse Leydig cell steroidogenesis are briefly described, the stimulatory mechanisms are summarized, and the recent findings related to the alternative substances regulating male reproductive functions are also discussed.


Assuntos
Cordyceps , Animais , Desoxiadenosinas , Masculino , Reprodução
20.
Transl Neurosci ; 8: 9-14, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28400978

RESUMO

AIM: Status epilepticus (SE) results in the generation of reactive oxygen species (ROS), which contribute to seizure-induced brain injury. It is well known that oxidative stress plays a pivotal role in status epilepticus (SE). Thymoquinone (TQ) is a bioactive monomer extracted from black cumin (Nigella sativa) seed oil that has anti-inflammatory, anti-cancer, and antioxidant activity in various diseases. This study evaluated the protective effects of TQ on brain injury in a lithium-pilocarpine rat model of SE and investigated the underlying mechanism related to antioxidative pathway. METHODS: Electroencephalogram and Racine scale were used to value seizure severity. Passive-avoidance test was used to determine learning and memory function. Moreover, anti-oxidative activity of TQ was observed using Western blot and super oxide dismutase (SOD) activity assay. RESULTS: Latency to SE increased in the TQ-pretreated group compared with rats in the model group, while the total power was significantly lower. Seizure severity measured on the Racine scale was significantly lower in the TQ group compared with the model group. Results of behavioral experiments suggest that TQ may also have a protective effect on learning and memory function. Investigation of the protective mechanism of TQ showed that TQ-pretreatment significantly increased the expression of Nrf2, HO-1 proteins and SOD in the hippocampus. CONCLUSION: These findings showed that TQ attenuated brain injury induced by SE via an anti-oxidative pathway.

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