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1.
Eur Heart J ; 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32588060

RESUMO

AIM: The present study aimed to assess the benefits of two-stent techniques for patients with DEFINITION criteria-defined complex coronary bifurcation lesions. METHODS AND RESULTS: In total, 653 patients with complex bifurcation lesions at 49 international centres were randomly assigned to undergo the systematic two-stent technique (two-stent group) or provisional stenting (provisional group). The primary endpoint was the composite of target lesion failure (TLF) at the 1-year follow-up, including cardiac death, target vessel myocardial infarction (TVMI), and clinically driven target lesion revascularization (TLR). The safety endpoint was definite or probable stent thrombosis. At the 1-year follow-up, TLF occurred in 37 (11.4%) and 20 (6.1%) patients in the provisional and two-stent groups, respectively [77.8%: double-kissing crush; hazard ratio (HR) 0.52, 95% confidence interval (CI) 0.30-0.90; P = 0.019], largely driven by increased TVMI (7.1%, HR 0.43, 95% CI 0.20-0.90; P = 0.025) and clinically driven TLR (5.5%, HR 0.43, 95% CI 0.19-1.00; P = 0.049) in the provisional group. At the 1 year after indexed procedures, the incidence of cardiac death was 2.5% in the provisional group, non-significant to 2.1% in the two-stent group (HR 0.86, 95% CI 0.31-2.37; P = 0.772). CONCLUSION: For DEFINITION criteria-defined complex coronary bifurcation lesions, the systematic two-stent approach was associated with a significant improvement in clinical outcomes compared with the provisional stenting approach. Further study is urgently warranted to identify the mechanisms contributing to the increased rate of TVMI after provisional stenting. STUDY REGISTRATION: http://www.clinicaltrials.com; Identifier: NCT02284750.

3.
ACS Nano ; 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32574035

RESUMO

Carbon nanotube (CNT) field-effect transistor (FET)-based biosensors have shown great potential for ultrasensitive biomarker detection, but challenges remain, which include unsatisfactory sensitivity, difficulty in stable functionalization, incompatibility with scalable fabrication, and nonuniform performance. Here, we describe ultrasensitive, label-free, and stable FET biosensors built on polymer-sorted high-purity semiconducting CNT films with wafer-scale fabrication and high uniformity. With a floating gate (FG) structure using an ultrathin Y2O3 high-κ dielectric layer, the CNT FET biosensors show amplified response and improved sensitivity compared with those sensors without Y2O3, which is attributed to the chemical gate-coupling effect dominating the sensor response. The CNT FG-FETs are modified to selectively detect specific disease biomarkers, namely, DNA sequences and microvesicles, with theoretical record detection limits as low as 60 aM and 6 particles/mL, respectively. Furthermore, the biosensors exhibit highly uniform performance over the 4 in. wafer as well as superior bias stress stability. The FG CNT FET biosensors could be extended as a universal biosensor platform for the ultrasensitive detection of multiple biological molecules and applied in highly integrated and multiplexed all CNT-FET-based sensor architectures.

4.
Int J Mol Med ; 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32582981

RESUMO

Diabetes­associated cognitive decline is a recently identified a potential complication of diabetes. The present study was designed to examine the effects of troxerutin, a potent antioxidant, on cognitive function in rats with streptozotocin­induced diabetes and to further explore the potential underlying mechanisms. Cognitive functions were investigated by the Morris water maze test. The malondialdehyde (MDA) level and superoxide dismutase (SOD) activity in the hippocampus were assessed as the parameters of oxidative stress. Subunits of the NADPH oxidase (NOX) expression and nuclear factor erythroid 2­related factor 2/antioxidant responsive element (Nrf2/ARE) signaling pathway were detected to explore the potential underlying mechanisms. The water maze test revealed that troxerutin significantly improved cognitive impairment in diabetic rats. Troxerutin treatment attenuated oxidative stress in the hippocampus of diabetic rats, as evidenced by the decreased MDA level and the increased SOD activity. Moreover, troxerutin activated the Nrf2/ARE signaling pathway via Nrf2 nuclear translocation in the cells in the hippocampus of diabetic rats. Troxerutin elevated the expression levels of the antioxidant enzymes, heme oxygenase­1 (HO­1) and NAD(P)H:quinone oxidoreductase (NQO1), and decreased the expression levels of the NOX subunits, gp91phox, p47phox and p22phox. On the whole, these findings demonstrate that troxerutin exerts neuroprotective effects against diabetes­associated cognitive decline by suppressing oxidative stress in the hippocampus of rats with streptozotocin­induced diabetes. Troxerutin may thus prove to be a potential therapeutic medicine for the treatment of diabetes­associated cognitive decline.

5.
J Agric Food Chem ; 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32578426

RESUMO

Hydroxytyrosol (HT) is a natural antioxidant with many associated health benefits. In this study, we established efficient enzymatic cascades for the synthesis of hydroxytyrosol (HT) from biobased L-tyrosine. Firstly, the dopamine-mediated route for HT production was investigated. The combination of native hydroxylase (HpaBC) from Escherichia coli and L-DOPA decarboxylase (DODC) from Pseudomonas putida could efficiently convert 5 mM L-tyrosine into dopamine with conversion above 90%. However, further incorporation of monoamine oxidase (MAO) from Micrococcus luteus and phenylacetaldehyde reductase (PAR) from Solanum lycopersicum only resulted in 3.47 mM HT with 69.4% conversion. Therefore, a second enzyme cascade that comprises HpaBC from E. coli, L-amino acid deaminase (LAAD) from Proteus mirabilis, α-keto-acid decarboxylase (ARO10) from Saccharomyces cerevisiae and PAR from S. Lycopersicum was designed. This enzymatic route showed higher catalytic activity and efficiently synthesize HT. 24.27 mM HT was obtained from 25 mM L-tyrosine with high conversion of 97.1%, and 32.35 mM HT was produced using 50 mM L-tyrosine, which represent the highest HT titer using L-tyrosine as substrate reported to date. In summary, we have developed a green and sustainable platform for efficient HT enzymatic synthesis.

6.
J Exp Bot ; 2020 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-32474603

RESUMO

The function of KNOTTED ARABIDOPSIS THALIANA7 (KNAT7) transcription factor is still unclear since it appears either as a negative or a positive regulator for secondary cell wall deposition with its loss-of-function mutant displaying thicker interfascicular and xylary fiber cell walls but thinner vessel cell walls in inflorescence stems. To explore the exact function of KNAT7, Class II KNOTTED1-like homeobox (KNOXII) genes including KNAT3, KNAT4 and KNAT5 were studied together. By chimeric repressor technology, we found that both KNAT3 and KNAT7 repressors exhibited a similar dwarf phenotype. Both KNAT3 and KNAT7 genes were expressed in the inflorescence stems and the knat3 knat7 double mutant exhibited a dwarf phenotype similar to the repressor lines. Stem cross-section of knat3 knat7 displayed an enhanced irregular xylem phenotype as compared to the single mutants, and its cell wall thickness in xylem vessels and interfascicular fibers were significantly reduced. Cell wall chemical composition analysis revealed that syringyl lignin significantly decreased while guaiacyl lignin increased in the knat3 knat7 double mutant. Coincidently, transcriptome of knat3 knat7 showed that most lignin pathway genes were activated, whereas syringyl lignin related gene Ferulate 5-Hydroxylase (F5H) was obviously downregulated. Protein interaction analysis discovered that KNAT3 and KNAT7 can form a heterodimer, and KNAT3, but not KNAT7, can interact with the key second cell wall formation transcription factors NST1/2, which suggests that the KNAT3 NST1/2 heterodimer complex regulates F5H to promote syringyl lignin synthesis. These results indicate that KNAT3 and KNAT7 synergistically work together to promote secondary cell wall biosynthesis.

7.
J Cardiothorac Surg ; 15(1): 125, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503651

RESUMO

BACKGROUND: Transthoracic esophagectomy is a crucial independent risk factor for the incidence of postoperative cardiopulmonary complications in elderly or comorbid patients. To reduce postoperative cardiopulmonary complications and promote postoperative recovery. We made an attempt to adopt the single-port inflatable mediastinoscopy combined with laparoscopy for radical esophagectomy in esophageal cancer to observe the clinical application and effect. METHOD: Data of patients with esophageal carcinoma were collected in the Hebei General Hospital from May 2018 to November 2019. The operation time, surgical blood loss, the number of dissected lymph nodes, duration of drainage tube, duration of time on the ventilator, the length of stay in ICU, postoperative complications, the length of postoperative hospital stay were collected to assess the safety and feasibility of the single-port inflatable mediastinoscopy combined with laparoscopy for radical esophagectomy in esophageal cancer. RESULTS: A total of 22 patients with esophageal cancer were analyzed in our research. There were no cases of conversion to thoracotomy、perioperative death or postoperative cardiopulmonary complications. The average operation time of all enrolled patients was 4.26 ± 0.52 h、The surgical blood loss was 142 ± 36.50 ml、The amount of dissected lymph nodes were 21.6 ± 4.2、The duration of drainage tube was 5.8 ± 2.5 days、The duration of time on the ventilator was 6.5 ± 3.4 h、The length of stay in ICU was 1.2 ± 0.4 days、The postoperative hospital stay was 12.6 ± 2.5 days. Among all the enrolled patients, one patient (4.5%) developed anastomotic fistula on the third day after surgery. Anastomotic stricture was found in 5 patients (22.7%). Pleural effusion was found in 4 cases (18.2%). Recurrent laryngeal nerve injury caused hoarseness or cough after drinking water in 3 cases (13.6%).There was one patient (4.5%) of conversion to laparotomy as the patient had serious peritoneal adhesion. All of the patients were discharged successfully. CONCLUSION: Our results showed that this surgery of single-port inflatable mediastinoscopy combined with laparoscopy for radical esophagectomy in esophageal squamous cell carcinoma is safe and feasible. The feasibility and safety could be further and better investigated with a RCT to achieve more conclusive results.

8.
Sci Rep ; 10(1): 8976, 2020 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-32488145

RESUMO

High temperatures (HT) before heading strongly inhibit the development of spikelets in rice. Spermidine (Spd) can improve rice's resistance to HT stress; however, the mechanism underlying this effect has not been elucidated. This study investigated several parameters, including yield, superoxide anion (O2.-), protective enzyme activities, and polyamine content, in a heat-sensitive genotype, Shuanggui 1. The yield and yield components decreased dramatically when subjected to HT stress, while this reduction could be partially recovered by exogenous Spd. Spd also slowed the generation rate of O2.- and increased protective enzyme, superoxide dismutase (SOD) and catalase (CAT) activities both under normal and high temperatures, which suggested that Spd may participate in the antioxidant system. Furthermore, genes involved in polyamine synthesis were analyzed. The results show that HT before heading significantly increased the expression of arginine decarboxylase OsADC1, Spd synthase OsSPDS1 and OsSPDS3 and had little effect on the expression of the S-adenosylmethionine decarboxylase OsSAMDC2 and ornithine decarboxylase OsODC1. In addition, exogenous Spd considerably reduced the expression of OsSAMDC2, OsSPDS1 and OsSPDS3 under HT but not the expression of OsADC1. The above mentioned results indicate that the exogenous Spd could help young rice spikelets to resist HT stress by reducing the expression of OsSAMDC2, OsSPDS1 and OsSPDS3, resulting in higher levels of endogenous Spd and Spm, which were also positively correlated with yield. In conclusion, the adverse effect of HT stress on young spikelets seems to be alleviated by increasing the amounts of Spd and Spm, which provides guidance for adaptation to heat stress during rice production.

10.
Science ; 368(6493): 850-856, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32439787

RESUMO

Single-walled carbon nanotubes (CNTs) may enable the fabrication of integrated circuits smaller than 10 nanometers, but this would require scalable production of dense and electronically pure semiconducting nanotube arrays on wafers. We developed a multiple dispersion and sorting process that resulted in extremely high semiconducting purity and a dimension-limited self-alignment (DLSA) procedure for preparing well-aligned CNT arrays (within alignment of 9 degrees) with a tunable density of 100 to 200 CNTs per micrometer on a 10-centimeter silicon wafer. Top-gate field-effect transistors (FETs) fabricated on the CNT array show better performance than that of commercial silicon metal oxide-semiconductor FETs with similar gate length, in particular an on-state current of 1.3 milliamperes per micrometer and a recorded transconductance of 0.9 millisiemens per micrometer for a power supply of 1 volt, while maintaining a low room-temperature subthreshold swing of <90 millivolts per decade using an ionic-liquid gate. Batch-fabricated top-gate five-stage ring oscillators exhibited a highest maximum oscillating frequency of >8 gigahertz.

11.
ACS Nano ; 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32422043

RESUMO

Monolithic optoelectronic integration based on a single material is a major pursuit in the fields of nanophotonics and nanoelectronics in order to meet the requirements of future fiber-optic telecommunication systems and on-chip optical interconnection systems. However, the incompatibility between silicon-based electronics and germanium or compound semiconductor-based photonics makes it very challenging to realize optoelectronic integration based on a single material. Here, the integration between silicon waveguides and a carbon nanotube (CNT) optoelectronic system is demonstrated. Waveguide-integrated photodetectors based on the CNT exhibit 12.5 mA/W photoresponsivity at 1530 nm, which presents an improvement of 97.6 times enhanced absorption efficiency compared to that without the waveguide. Multiplied output signals of cascading photodetectors are used to control the output of CNT-based logic gates, thereby demonstrating that the CNT-based optoelectronic integration system is compatible with silicon photonics. Our work indicates that carbon nanotubes have the potential for future integration between nanophotonics and nanoelectronics on a single chip.

12.
J Dermatolog Treat ; : 1-5, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32431191

RESUMO

Background: Tacrolimus is a new type immunosuppressant. The aim of this study was to evaluate the effectiveness of topical tacrolimus 0.1% ointment at 2 different frequencies in treating patients with exfoliative cheilitis.Methods: A total of 40 patients with exfoliative cheilitis were randomly divided into the QD group receiving topical tacrolimus 0.1% ointment once a day or the QOD group receiving topical tacrolimus 0.1% ointment once-two-day. Patients were also applied wet dressing of saline twice a day. The effectiveness of treatment was defined as the percentage of improvement in signs or symptoms.Results: 37 patients completed the 2-week treatment. And, a full set was analyzed. The effectiveness of topical tacrolimus 0.1% ointment for relief in objective sign and subjective symptom was 50% and 67.5%% in the QD group, respectively. For the QOD group, the effectiveness of sign and symptom relief was 50% and 73.5%. There was no significant difference of effectiveness between application topical tacrolimus once a day and once 2 days.Conclusion: Our data suggested that application of topical tacrolimus 0.1% ointment once a day and once 2 days had similar clinical effectiveness for sign and symptom relief in patients with exfoliative cheilitis.

13.
Carbohydr Polym ; 239: 116237, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32414446

RESUMO

Nitrogen fertilizer is an essential nutrient for rice (Oryza sativa L.), especially, for newly bred 'super' rice cultivars with great yield potential. The effects of nitrogen fertilizer (0, 100, 200, 300, 400 kg N ha-1) on the physicochemical properties of two high yielding 'super' rice Yongyou 2640 and Lianjing 7 were investigated in this study. The application of nitrogen fertilizer affects the structure of rice starch, thus changing its functional properties, which ultimately leads to a change in the quality of both rice cultivars. There were dose effects of nitrogen fertilizer on grain quality. Grain quality was improved under moderate nitrogen inputs (100 & 200 kg N ha-1), but deteriorated at excessive nitrogen levels (300 & 400 kg N ha-1). With moderate N application, starch granule size increased and the surface of starch granule became smoother; there were higher proportion of short branch-chain of amylopectin and lower proportion of long branch-chain of amylopectin with low relative crystallinity, lower degree of order of structure and higher content of amorphous structure at the outer region of the starch granules; peak viscosity, hot viscosity, breakdown value were increased while setback and pasting temperature were decreased; gelatinization temperature, gelatinization enthalpy, retrogradation enthalpy, retrogradation percentage, hardness were decreased while viscosity were increased. At excessive nitrogen inputs, the grain quality was deteriorated and the opposite results of structure and physicochemical properties of rice starch were observed. These results indicate that nitrogen fertilizer significantly affected the structure and physicochemical properties of rice starch, and appropriate fertilization would improve rice grain quality.

14.
Artigo em Inglês | MEDLINE | ID: mdl-32462620

RESUMO

Copper (Cu), with many documented cases of Cu toxicity in agriculture lands, is becoming an increasingly common issue in and elsewhere in China. However, fibrous crop such as jute is being used as phytoremediation candidate in Cu-contaminated soils due to its huge biomass. A pot experiment was conducted using four different varieties (HT, C-3, GC, and SH) of jute grown in highly Cu-contaminated soil (2221 mg kg-1), collected from Hubei Province, China. Results from this study showed that C-3 and HT were more resistant to Cu stress, while GC and SH had a serious effect due to high concentration of Cu and a significant decrease in growth and biomass. Furthermore, Cu in roots, leaves, stem core, and bast were higher in C-3 and HT compared with GC and SH. Likewise, at post-harvesting stage, maximum Cu concentration from Cu-contaminated soil was extracted by C-3 and HT while small amount was accumulated by GC and SH. The high content of malondialdehyde (MDA) in the leaves of GC and SH indicated that Cu induced oxidative damage while the antioxidative enzyme activities of superoxidase dismutase (SOD) and peroxidase (POD) were increased to scavenge reactive oxygen species (ROS) formed during oxidative stress in the plants. Conclusively, it can be identified that when grown in Cu-contaminated soil, C-3 and HT have greater ability to grow in polluted soils and possible phytoremediation materials to revoke a large amount of Cu.

15.
Nano Lett ; 20(6): 4354-4361, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32357000

RESUMO

Compared to van der Waals two-dimensional (2D) layers with lateral covalent bonds, metallic bonding systems favor close-packed structures, and thus, free-standing 2D metals have remained, for the most part, elusive. However, a number of theoretical studies suggest a number of metals can exist as 2D materials and a few early experiments support this notion. Here we demonstrate free-standing single-atom-thick crystalline chromium (Cr) suspended membranes using aberration-corrected transmission electron microscopy and image simulations. Density functional theory studies confirm the 2D Cr membranes have an antiferromagnetic ground state making them highly attractive for spintronic applications. Moreover, the work also helps consolidate the existence of a new family of 2D metal layers.

16.
Dent Mater ; 36(7): e229-e240, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32471559

RESUMO

OBJECTIVE: Maxillary sinus floor augmentation (MSFA) is commonly used to increase the alveolar bone height in the posterior maxilla before implant placement. In the present study, we evaluated if the injectable thermosensitive chitosan/ß-sodium glycerophosphate disodium salt hydrate/gelatin (CS/GP/GA) hydrogel carried erythropoietin (EPO) could enhance the new bone formation for MSFA in vivo. METHODS: EPO-CS/GP/GA hydrogel was prepared by ionic crosslinking. Then, characteristics of EPO-CS/GP/GA were evaluated by morphology, injectable property and pH on the gelling time (GT). The release profile of EPO was evaluated by enzyme linked immunosorbent assay (ELISA), and effects of EPO on proliferation and osteoblastic differentiation of bone marrow stromal cells (BMSC) were analyzed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and reverse transcription quantitative real-time PCR (RT-qPCR), respectively. Finally, EPO-CS/GP/GA was injected into the maxillary sinus floor of the rabbit to test the potential application for MSFA. RESULTS: Results showed that GT was decreased with the increase of pH value. The GT was 110±15s at pH 7.0. SEM images showed that the CS/GP/GA hydrogel had a sponge network structure. Results from ELISA assay revealed that the cumulative release of EPO from the EPO-CS/GP/GA hydrogel reached 67% at 4h, and 94% at 15 days. MTT assay showed that EPO within EPO-CS/GP/GA hydrogel could significantly promote proliferation of BMSCs compared to control group (p<0.001) . Results of RT-qPCR assays demonstrated that the expression of Sp7, Runx2, Col I and Alp were significantly increased from EPO-CS/GP/GA group compared to control group on day 14 (p<0.001). Importantly, EPO-CS/GP/GA hydrogel could significantly induce bone formation (81.98mm3) compared with control group (43.11mm3) after 12 weeks post-implantation in vivo. The calculation of thickness of mesenchymal condensation indicated that thickness of mesenchymal condensation was significantly increased from EPO-CS/GP/GA group (∼121.4µm) compared to control group (∼37µm) resulting in enhancing intramembranous ossification. SIGNIFICANCE: The EPO-CS/GP/GA hydrogel provides a novel strategy for MSFA with a minimally invasive way.

17.
ACS Nano ; 14(4): 5099-5110, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32275391

RESUMO

A pioneering epidemic study has revealed a strong association between obesity and the risk of colitis. In this study, a high fat diet was found to significantly aggravate colitis induced by dextran sulfate sodium (DSS). Meanwhile, a high fat diet changed the miRNA profile of the visceral adipose exosomes, switching the exosomes from anti-inflammatory to a pro-inflammatory phenotype. Strikingly, these inflammatory exosomes efficiently circulated into the lamina propria of the intestine, while these exosomes predisposed the intestine to inflammation via promoting macrophage M1 polarization. Mechanistically, the exosomes promoted M1 differentiation at least partially via transferring pro-inflammatory miRNAs, such as miR-155. Moreover, exosome-mediated miR-155 inhibitor delivery significantly prevented DSS-induced colitis. Together, the study has revealed an exosomal pathway of how obesity aggravates colitis and proposes an exosome-based intervention strategy for colitis management.

18.
Int J Syst Evol Microbiol ; 70(3): 1777-1784, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32234113

RESUMO

A Gram-stain-negative, strictly aerobic, oval-shaped, non-motile bacterium with no flagella, designated strain SCR17T, was isolated from a shrimp gill habitat in Tangyin hydrothermal field of Okinawa Trough. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SCR17T formed a lineage within the family 'Rhodobacteraceae', and shared 16S rRNA gene sequence similarity of 93.2-96.2 % to the related genera Aquicoccus and Roseivivax. Strain SCR17T was able to grow with 0-14 % (w/v) NaCl (optimum, 9-10 %). The sole respiratory quinone was ubiquinone-10. The major polar lipids of strain SCR17T comprised phosphatidylcholine (PC), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), an unidentified aminolipid (AL), an unidentified phospholipid (PL) and an unidentified lipid (L). The predominant fatty acids (more than 10 % of the total fatty acids) were C18 : 1ω7c or/and C18 : 1ω6c, anteiso-C15 : 0, C16 : 0 and C19 : 0 cyclo ω8c . The genomic DNA G+C content of strain SCR17T was 67.7 mol%. Based on polyphasic taxonomic analyses, strain SCR17T is considered to represent a novel species in a new genus of the family 'Rhodobacteraceae', for which the name Carideicomes alvinocaridis gen. nov., sp. nov. is proposed. The type strain of Carideicomes alvinocaridis is SCR17T (=JCM 33426T=MCCC 1K03732T). The discovery of a novel host-associated bacterium in hydrothermal fields provides an opportunity for the study of host-bacterial symbiosis in extreme environments.


Assuntos
Decápodes/microbiologia , Brânquias/microbiologia , Filogenia , Rhodobacteraceae/classificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Oceano Pacífico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Rhodobacteraceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
19.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(2): 155-159, 2020 Apr 01.
Artigo em Chinês | MEDLINE | ID: mdl-32314888

RESUMO

OBJECTIVE: This work aimed to evaluate the effect of different surface treatments on the shear bond strength of resin nano ceramic to resin cement, thereby providing a theoretical basis for the improvement of clinical application. METHODS: A total of 150 specimens (10 mm×10 mm×3 mm) were milled from resin nano ceramic blocks (Lava Ultimate) using computer-aided design/computer aided manufacturing(CAD/CAM) technology. The specimens were randomly divided into five groups according to the surface treatment performed, as follows: control, sandblasted, sandblasted+silane, hydrofluoric acid, and hydrofluoric acid+silane groups. After the corresponding surface treatment, the specimens were cemented using Single Bond Universal Adhesive and RelyXTM Ultimate ClickerTM adhesive resin cement. All cemented specimens were placed in distilled water for 24 h and 30 days and subjected to a shear bond strength test in a universal testing machine. RESULTS: The surface treatment and water storage periods showed significant effects on bond strength. Surface treatment with sandblasted+silane showed the highest shear strength values among all tested groups, and the difference was statistically significant (P<0.05). A difference was observed between the control and hydrofluoric acid groups, and both had significantly difference compared with other groups (P<0.05). Sandblasted and hydrofluoric acid+silane groups were not statistically different, and both had significantly difference compared with other groups (P<0.05). CONCLUSIONS: The surface of resin nanoceramic treated by sand-blasted, sandblasted+silane, and hydrofluoric acid+silane can improve the bond strength. The sandblasted+silane group had the best the shear bond strength among the groups.


Assuntos
Colagem Dentária , Cimentos de Resina , Cerâmica , Porcelana Dentária , Análise do Estresse Dentário , Teste de Materiais , Resistência ao Cisalhamento , Silanos , Propriedades de Superfície
20.
Protein Pept Lett ; 2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286937

RESUMO

BACKGROUND: The Yes-associated protein (YAP) is a central regulator of Hippo pathway involved in carcinogenesis, which functions through interaction with TEA domain (TEAD) transcription factors. Pharmacological disruption of YAP- TEAD4 complexes has been recognized as a potential therapeutic strategy against diverse cancers by suppressing the oncogenic activity of YAP. OBJECTIVE: We systematically examine the crystal structure of YAP complex with TEAD4 and rationally identify two hotspot segments at the complex interface; they could be exploited as self-inhibitory peptides to target the complex interaction. METHODS: Two peptides, termed PS-1 and PS-2 are split from the interfacial context of YAP protein. Dynamics simulations, energetics analyses and fluorescence polarizations are employed to characterize the intrinsic disorder as well as binding energy/affinity of the two YAP peptides to TEAD4 protein. RESULT: The native conformation of PS-2 peptide is a cyclic loop, which is supposed to be constrained by adding a disulfide bond across the spatially vicinal residue pair Arg87-Phe96 or Met86-Phe95 at the peptide's two ends, consequently resulting in two intramolecular cyclized counterparts of linear PS-2 peptide, namely PS-2(cyc87,96) and PS-2(cyc86,95). The linear PS-2 peptide is determined as a weak binder of TEAD4 (Kd = 190 µM), while the two cyclic PS-2(cyc87,96) and PS-2(cyc86,95) peptides are measured to have moderate or high affinity towards TEAD4 (Kd = 21 and 45 µM, respectively). CONCLUSION: PS-1 and PS-2 peptides are highly flexible and cannot maintain in native active conformation when splitting from the interfacial context, and thus would incur a considerable entropy penalty upon rebinding to the interface. Cyclization does not influence the direct interaction between PS-2 peptide and TEAD4 protein, but can largely reduce the intrinsic disorder of PS-2 peptide in free state and considerably minimize indirect entropy effect upon the peptide binding.

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