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1.
Small ; : e2403486, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-39031678

ABSTRACT

The development of high-performance organic photovoltaic materials is of crucial importance for the commercialization of organic solar cells (OSCs). Herein, two structurally simple donor-π-conjugated linker-acceptor (D-π-A)-configured small-molecule donors with methyl-substituted triphenylamine as D unit, 1,1-dicyanomethylene-3-indanone as A unit, and thiophene or furan as π-conjugated linker, named DTICPT and DTICPF, are developed. DTICPT and DTICPF are facilely prepared via a two-step synthetic process with simple procedures. DTICPF with a furan π-conjugated linker exhibits stronger and broader optical absorption, deeper highest occupied molecular orbital (HOMO) energy levels, and better charge transport, compared to its thiophene analog DTICPT. As a result, vacuum-deposited OSCs based on DTICPF: C70 show an impressive power conversion efficiency (PCE) of 9.36% (certified 9.15%) with short-circuit current density (Jsc) up to 17.49 mA cm-2 (certified 17.56 mA cm-2), which is the highest Jsc reported so far for vacuum-deposited OSCs. Besides, devices based on DTICPT: C70 and DTICPF: C70 exhibit excellent long-term stability under different aging conditions. This work offers important insights into the rational design of D-π-A configured small-molecule donors for high efficient and stable vacuum-deposited OSCs.

2.
Int Immunopharmacol ; 124(Pt B): 111030, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37844463

ABSTRACT

Hypoxic-ischemic encephalopathy (HIE) is a perinatal brain disease caused by hypoxia in neonates. It is one of the leading causes of neonatal death in the perinatal period, as well as disability beyond the neonatal period. Due to the lack of a unified and comprehensive treatment strategy for HIE, research into its pathogenesis is essential. Diallyl disulfide (DADS) is an allicin extract, with detoxifying, antibacterial, and cardiovascular disease protective effects. This study aimed to determine whether DADS can alleviate HIE induced brain damage in rats and oxygen-glucose deprivation (OGD)-induced pyroptosis in PC12 cells, as well as whether it can inhibit pyroptosis via the NLRP3/Caspase-1/IL-1ß signaling pathway. In vivo, DADS significantly reduced the cerebral infarction volume, alleviated inflammatory reaction, reduced astrocyte activation, promoted tissue structure recovery, improved pyroptosis caused by HIE and improved the prognosis following HI injury. In vitro findings indicated that DADS increased cell activity, decreased LDH activity and reduced the expression of pyroptosis-related proteins, including IL-1ß, IL-18, and certain inflammatory factors in PC12 cells caused by OGD. Mechanistically, DADS inhibited pyroptosis and protected against HIE via the NLRP3/Caspase-1/IL-1ß pathway. The specific inhibitor of caspase-1, VX-765, inhibited caspase-1 activation, and IL-1ß expression was determined. Additionally, the overexpression of NLRP3 reversed the protective effect of allicin against OGD-induced pyroptosis. In conclusion, these findings demonstrated that DADS inhibits the NLRP3/Caspase-1/IL-1ß signaling pathway and decreases HI brain damage.


Subject(s)
Hypoxia-Ischemia, Brain , Pyroptosis , Pregnancy , Female , Rats , Animals , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Animals, Newborn , Caspase 1/metabolism , Hypoxia-Ischemia, Brain/pathology , Oxygen/pharmacology , Brain/metabolism , Signal Transduction , Inflammasomes/metabolism
3.
BMC Oral Health ; 23(1): 705, 2023 09 30.
Article in English | MEDLINE | ID: mdl-37777729

ABSTRACT

BACKGROUND: Exopolysaccharides (EPS) are essential constituents of the extracellular matrix within oral biofilms and are significantly influenced by the local microenvironment. This study aimed to investigate the impact of two distinct antimicrobial agents, DJK-5 and chlorhexidine (CHX), on the EPS volume and pH levels in oral biofilms. METHODS: Oral biofilms obtained from two donors were cultured on hydroxyapatite discs for durations of 3 days, 1 week, 2 weeks, 3 weeks, and 4 weeks. Subsequently, these biofilms were subjected to treatment with 10 µg/mL DJK-5 or 2% CHX for 3 min. The impact of these antimicrobial treatments on factors such as the proportion of dead bacterial, in situ pH, and EPS volume within the biofilms was assessed using corresponding fluorescent probes. The examination was carried out utilizing confocal laser scanning microscopy, and the resulting images were analyzed with a focus on the upper and lower layers of the biofilm, respectively. RESULTS: DJK-5 exhibited a more potent bactericidal effect compared to CHX across the 3-day to 4-week duration of the biofilm (P < 0.05). The biofilms were acidic, with the upper layer being less acidic than the lower layer (P < 0.05). Both antimicrobial agents increased the pH, but DJK-5 had a greater effect than CHX (P < 0.05). The volume of EPS was significantly lower in DJK-5 treated biofilms compared to that of CHX, regardless of age or layer (P < 0.05). CONCLUSION: DJK-5 exhibited superior effectiveness in reducing viable bacteria and EPS volume, as well as in raising extracellular pH, as compared to chlorhexidine.


Subject(s)
Biofilms , Chlorhexidine , Humans , Chlorhexidine/pharmacology , Durapatite , Anti-Bacterial Agents/pharmacology , Hydrogen-Ion Concentration
5.
Adv Sci (Weinh) ; 9(26): e2201573, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35859254

ABSTRACT

Power conversion efficiency (PCE) and long-term stability are two vital issues for perovskite solar cells (PSCs). However, there is still a lack of suitable hole transport layers (HTLs) to endow PSCs with both high efficiency and stability. Here, NiOx nanoparticles are promoted as an efficient and 85 °C/85%-stable inorganic HTL for high-performance n-i-p PSCs, with the introduction of perovskite quantum dots (QDs) between perovskite and NiOx as systematic interfacial engineering. The QD intercalation enhances film morphology and assembly regulation of NiOx HTLs . Due to structure-function correlations, hole mobility within NiOx HTL is improved. And the hole extraction from perovskite to NiOx is also facilitated, resulting from reduced trap states and optimized energy level alignments. Hence, the promoted NiOx -based n-i-p PSCs exhibit high PCE (21.59%) and excellent stability (sustaining 85 °C aging in air without encapsulation). Furthermore, encapsulated solar modules with QDs-promoted NiOx HTLs show impressive stability during 85 °C/85% aging test for 1000 hours. With high transparency, QDs-promoted NiOx is also demonstrated to be an advanced HTL for semitransparent PSCs. This work develops promising NiOx inorganic HTL in n-i-p PSCs for manufacturing next-generation photovoltaic devices.

6.
J Am Chem Soc ; 144(24): 10736-10742, 2022 Jun 22.
Article in English | MEDLINE | ID: mdl-35671378

ABSTRACT

Herein, a nitrogen-embedded quintuple [7]helicene (N-Q7H) with an azapentabenzocorannulene core, which can be considered to be a helicene/azacorannulene hybrid π-system, was synthesized from azapentabenzocorannulene in a three-step process. N-Q7H is the first example of a multiple helicene with an azabuckybowl core. Single-crystal X-ray diffractometry unambiguously confirmed the structure of the propeller-shaped hybrid π-system. Owing to nitrogen-atom doping in the multiple helicenes and effective hybridization between the helicene and azacorannulene, N-Q7H exhibits considerably redshifted absorption and emission (yellow-to-green color change and green-to-near-infrared fluorescence change) relative to the azapentabenzocorannulene core. The broad absorption from the ultraviolet-visible to the NIR region is ascribable to the allowed transition between the highest occupied molecular orbital and the lowest unoccupied molecular orbital after symmetry breaking, as revealed by density functional theory calculations. Compared to previous propeller-shaped multiple helicenes with corannulene or hexabenzocoronene (etc.) as cores, N-Q7H demonstrates a significantly higher NIR fluorescence quantum efficiency of 28%. Additionally, the chiral-resolution and redox properties of N-Q7H were investigated. The excellent photophysical and inherent chiral properties of N-Q7H suggest that azapentabenzocorannulene can be used as an outstanding nitrogen-embedded core to construct novel multiple helicenes with wide application potential, including as NIR fluorescent bio-probes.

7.
Cell Commun Signal ; 20(1): 84, 2022 06 10.
Article in English | MEDLINE | ID: mdl-35689269

ABSTRACT

BACKGROUND: Neonatal hypoxic-ischemic brain injury (HIE) is caused by perinatal asphyxia, which is associated with various confounding factors. Although studies on the pathogenesis and treatment of HIE have matured, sub-hypothermia is the only clinical treatment available for HIE. Previous evidence indicates that chlorogenic acid (CGA) exerts a potential neuroprotective effect on brain injury. However, the role of CGA on neonatal HI brain damage and the exact mechanism remains elusive. Here, we investigate the effects of CGA on HI models in vivo and in vitro and explore the underlying mechanism. METHODS: In the in vivo experiment, we ligated the left common carotid artery of 7-day-old rats and placed the rats in a hypoxic box for 2 h. We did not ligate the common carotid artery of the pups in the sham group since they did not have hypoxia. Brain atrophy and infarct size were evaluated by Nissl staining, HE staining and 2,3,5-triphenyltetrazolium chloride monohydrate (TTC) staining. Morris Water Maze test (MWM) was used to evaluate neurobehavioral disorders. Western-blotting and immunofluorescence were used to detect the cell signaling pathway. Malondialdehyde (MDA) content test, catalase (CAT) activity detection and Elisa Assay was used to detect levels of inflammation and oxidative stress. in vitro experiments were performed on isolated primary neurons. RESULT: In our study, pretreatment with CGA significantly decreased the infarct volume of neonatal rats after HI, alleviated brain edema, and improved tissue structure in vivo. Moreover, we used the Morris water maze to verify CGA's effects on enhancing the learning and cognitive ability and helping to maintain the long-term spatial memory after HI injury. However, Sirt1 inhibitor EX-527 partially reversed these therapeutic effects. CGA pretreatment inhibited neuronal apoptosis induced by HI by reducing inflammation and oxidative stress. The findings suggest that CGA potentially activates Sirt1 to regulate the Nrf2-NF-κB signaling pathway by forming complexes thereby protecting primary neurons from oxygen-glucose deprivation (OGD) damage. Also, CGA treatment significantly suppresses HI-induced proliferation of glial. CONCLUSION: Collectively, this study uncovered the underlying mechanism of CGA on neonatal HI brain damage. CGA holds promise as an effective neuroprotective agent to promote neonatal brain recovery from HI-induced injury. Video Abstract.


Subject(s)
Brain Injuries , Hypoxia-Ischemia, Brain , Neuroprotective Agents , Animals , Animals, Newborn , Brain/metabolism , Brain Injuries/drug therapy , Brain Injuries/metabolism , Brain Injuries/pathology , Chlorogenic Acid/metabolism , Chlorogenic Acid/pharmacology , Chlorogenic Acid/therapeutic use , Hypoxia-Ischemia, Brain/complications , Hypoxia-Ischemia, Brain/drug therapy , Hypoxia-Ischemia, Brain/metabolism , Infarction/drug therapy , Infarction/metabolism , Infarction/pathology , Inflammation/metabolism , Ischemia/metabolism , NF-E2-Related Factor 2/metabolism , NF-kappa B/metabolism , Neuroprotective Agents/metabolism , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Rats , Rats, Sprague-Dawley , Signal Transduction , Sirtuin 1/metabolism
8.
Angew Chem Int Ed Engl ; 61(33): e202204334, 2022 Aug 15.
Article in English | MEDLINE | ID: mdl-35698274

ABSTRACT

Herein, a hetero(S,N)-quintuple [9]helicene (SNQ9H) molecule with an azacorannulene core was synthesized, currently representing the highest hetero-helicene reported in the field of multiple [n]helicenes. X-ray crystallography indicated that SNQ9H includes not only a propeller-shaped conformer SNQ9H-1, but also an unforeseen quasi-propeller-shaped conformer SNQ9H-2. Different conformers were observed for the first time in multiple [n≥9]helicenes, likely owing to the doping of heteroatomic sulfurs in the helical skeletons. Remarkably, the ratio of SNQ9H-1 to SNQ9H-2 can be regulated in situ by the reaction temperature. Experimental studies on the photophysical and redox properties of SNQ9H and theoretical calculations clearly demonstrated that the electronic structures of SNQ9H depend on their molecular conformations. The strategy of introducing heteroatomic sulfurs into the helical skeleton may be useful in constructing various conformers of higher multiple [n]helicenes in the future.

9.
Nanomaterials (Basel) ; 12(9)2022 Apr 22.
Article in English | MEDLINE | ID: mdl-35564135

ABSTRACT

Due to the partially reduced π-conjugation of the fullerene cage, multi-functionalized fullerene derivatives exhibit remarkable fluorescent properties compared to pristine fullerenes, which have high potential for application in organic light-emitting diodes (OLEDs). In this study two multi-functionalized C70 derivatives, C70(OCH3)10[C(COOEt)2] and C70(OCH3)10[C(COOEt)2]2, with excellent fluorescence properties, were designed and synthesized. Compared with C70(OCH3)10 containing a single kind of functional group, both the C70(OCH3)10[C(COOEt)2] and C70(OCH3)10[C(COOEt)2]2 exhibited enhanced fluorescence properties with blue fluorescence emission. The fluorescence quantum yields of the C70(OCH3)10[C(COOEt)2] and C70(OCH3)10[C(COOEt)2]2 were 1.94% and 2.30%, respectively, which were about ten times higher than that of C70(OCH3)10. The theoretical calculations revealed that the multi-functionalization of the C70 increased the S1-T1 energy gap, reducing the intersystem crossing efficiency, resulting in the higher fluorescence quantum yield of the C70 derivatives. The results indicate that multi-functionalization is a viable strategy to improve the fluorescence of fullerene derivatives.

10.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(3): 273-278, 2022 Mar 15.
Article in English, Chinese | MEDLINE | ID: mdl-35351257

ABSTRACT

OBJECTIVES: To study the application value of metagenomic next-generation sequencing (mNGS) in children with severe infectious diseases. METHODS: An analysis was performed on the clinical data and laboratory test results of 29 children with severe infection who were admitted to the Second Affiliated Hospital of Wenzhou Medical University from June 2018 to December 2020. Conventional pathogen culture was performed for the 29 specimens (27 peripheral blood specimens and 2 pleural effusion specimens) from the 29 children, and mNGS pathogen detection was performed at the same time. RESULTS: Among the 29 children, 2 tested positive by conventional pathogen culture with 2 strains of pathogen, and the detection rate was 7% (2/29); however, 20 children tested positive by mNGS with 38 strains of pathogen, and the detection rate was 69% (20/29). The pathogen detection rate of mNGS was significantly higher than that of conventional pathogen culture (P<0.05), and mNGS could detect the viruses, fungi, and other special pathogens that conventional pathogen culture failed to detect, such as Orientia tsutsugamushi. The univariate analysis showed that gender, routine blood test results, C-reactive protein, procalcitonin, D-dimer, radiological findings, and whether antibiotics were used before admission did not affect the results of mNGS (P>0.05). CONCLUSIONS: Compared with conventional pathogen culture, mNGS is more sensitive for pathogen detection, with fewer interference factors. Therefore, it is a better pathogenic diagnosis method for severe infectious diseases in children.


Subject(s)
Communicable Diseases , Metagenomics , Anti-Bacterial Agents , Child , High-Throughput Nucleotide Sequencing/methods , Humans , Metagenomics/methods , Sensitivity and Specificity
11.
Oxid Med Cell Longev ; 2021: 6654954, 2021.
Article in English | MEDLINE | ID: mdl-34046147

ABSTRACT

Hypoxic-ischemic encephalopathy (HIE) is recognized as the main cause of neonatal death, and efficient treatment strategies remain limited. Given the prevalence of HIE and the associated fatality, further studies on its pathogenesis are warranted. Oxidative stress and neuroinflammatory injury are two important factors leading to brain tissue injury and nerve cell loss in HIE. Neferine, an alkaloid extracted from lotus seed embryo, exerts considerable effects against several diseases such as cancers and myocardial injury. In this study, we demonstrated the neuroprotective effect of neferine on HIE and hypothesized that it involves the inhibition of neuronal pyroptosis, thereby ameliorating neurological inflammation and oxidative stress. We demonstrated that the mRNA levels of proteins associated with pyroptosis including caspase-1, the caspase adaptor ASC, gasdermin D, interleukin- (IL-) 18, IL-1ß, and some inflammatory factors were significantly increased in neonatal HIBD model rats compared to those in the control group. The increase in these factors was significantly suppressed by treatment with neferine. We stimulated PC12 cells with CoCl2 to induce neuronal HIBD in vitro and investigated the relationship between neferine and pyroptosis by altering the expression of the NLRP3 inflammasome. The overexpression of NLRP3 partially reversed the neuroprotective effect of neferine on HIBD, whereas NLRP3 knockdown further inhibited caspase-1 activation and IL-1ß and IL18 expression. In addition, simultaneous alteration of NLRP3 expression induced changes in intracellular oxidative stress levels after HIBD. These findings indicate that neferine ameliorates neuroinflammation and oxidative stress injury by inhibiting pyroptosis after HIBD. Our study provides valuable information for future studies on neferine with respect to neuroinflammation and pyroptosis.


Subject(s)
Benzylisoquinolines/therapeutic use , Brain Damage, Chronic/drug therapy , Brain Diseases/drug therapy , Drugs, Chinese Herbal/therapeutic use , Hypoxia-Ischemia, Brain/drug therapy , Inflammasomes/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Animals , Benzylisoquinolines/pharmacology , Drugs, Chinese Herbal/pharmacology , Humans , Rats , Rats, Sprague-Dawley
12.
Aust Endod J ; 47(2): 122-129, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33729636

ABSTRACT

Stripping perforation is a possible complication in instrumentation of C-shaped canals. This study evaluated the minimum thickness of the root canal wall in C-shaped teeth after instrumentation. Twelve extracted C-shaped mandibular second molars (four teeth of type I, II and III each) were examined by CBCT (voxel size 90 µm) before and after instrumentation with WOG primary file. Micro-CT scans (voxel size 30 µm) were obtained after instrumentation. Percentage of canal wall area touched by the file and minimum thickness of dentine were measured and compared between CBCT and micro-CT. In type I C-shape canals, less than 10% of the canal wall area was touched by the instrument. In ten teeth, the shortest distance to root surface was from the instrumented area; no perforations occurred. CBCT and micro-CT measurements were in good agreement in ten cases; in two teeth, micro-CT revealed considerably shorter distance to root surface. The two shortest distances were 0.27 and 0.41 mm.


Subject(s)
Molar , Spiral Cone-Beam Computed Tomography , Tooth Root , Dentin/diagnostic imaging , Humans , Molar/diagnostic imaging , Tooth Root/anatomy & histology , Tooth Root/diagnostic imaging , X-Ray Microtomography
13.
Odontology ; 109(3): 625-631, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33403470

ABSTRACT

Apical pressure during root canal irrigation is regarded as a key factor affecting the risk of irrigant extrusion. The aim of this study was to examine the effect of apical size on the apical pressure by positive and negative pressure syringe-needle and multisonic negative pressure irrigation. An extracted maxillary first molar with two separate buccal roots, one palatal root and four canals was selected. The roots of the molar were fixed in a specially made apparatus to acquire the apical pressure of the four root canals separately. The apical sizes tested were from sizes 10, 30, 40, 50, 60, 70, 80, 90, 110. Multisonic negative pressure irrigation protocol was as recommended by the manufacturer (45 mL/min), syringe-needle irrigation was done using 30-G side-vented needle 3 mm from the working length at 5 mL/min as a conventional positive pressure irrigation (SNI), and as negative pressure irrigation (NPSNI) using suction. Apical pressure by SNI was measured also at 10 mL/min with an open-ended 30G needle, for the smallest and largest apical sizes. Apical pressures by SNI stayed positive, except when suction was used (NPSNI). The apical pressure by multisonic negative pressure irrigation remained negative in all situations. With increasing apical size, apical pressure by SNI decreased, whereas with multisonic negative pressure irrigation and NPSNI, it was not affected by apical size. Large apical size did not result in higher apical pressure values compared to small apical sizes.


Subject(s)
Root Canal Irrigants , Therapeutic Irrigation , Dental Pulp Cavity , Molar , Root Canal Preparation , Root Canal Therapy , Sodium Hypochlorite , Syringes
14.
Int Immunopharmacol ; 89(Pt B): 107095, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33096360

ABSTRACT

Hypoxia and the resultant decreases in cerebral blood flow in the perinatal period can lead to neonatal hypoxic-ischemic (HI) brain injury, which can, in turn, cause severe disability or even death. However, the efficacy of current treatment strategies remains limited. Several studies have demonstrated that lipoxin A4 (LXA4), as one of the earliest types of endogenous lipid mediators, can inhibit the accumulation of neutrophils, arrest inflammation, and promote the resolution of inflammation. However, research on LXA4 in the nervous system has rarely been carried out. In the present study, we sought to investigate the protective effect of LXA4 on HI brain damage in neonatal rats, as well as the underlying mechanisms. Through experiments conducted using an HI animal model, we found that the LXA4 intervention promoted the recovery of neuronal function and tissue structure following brain injury while maintaining the integrity of the blood-brain barrier in addition to reducing cerebral edema, infarct volume, and inflammatory responses. Our results suggest that LXA4 interfered with neuronal oxygen-glucose deprivation insults, reduced the expression of inflammatory factors, inhibited apoptosis, and promoted neuronal survival in vitro. Finally, the LXA4 intervention attenuated HI-induced activation of inhibitor kappa B (IκB) and degradation of nuclear factor-κB (NF-κB). In conclusion, our data suggest that LXA4 exerts a neuroprotective effect against neonatal HI brain damage through the IκB/NF-κB pathway. Our findings will help inform future studies regarding the effects of LXA4 on neuroinflammation, blood-brain barrier integrity, and neuronal apoptosis.


Subject(s)
Hypoxia-Ischemia, Brain/prevention & control , Inflammation/metabolism , Lipoxins/pharmacology , Neuroprotective Agents/pharmacology , Signal Transduction/drug effects , Animals , Animals, Newborn , Apoptosis/drug effects , Behavior, Animal/drug effects , Blood-Brain Barrier/drug effects , Blood-Brain Barrier/metabolism , Brain Edema/metabolism , Brain Edema/prevention & control , Brain Injuries/etiology , Brain Injuries/metabolism , Brain Injuries/pathology , Brain Injuries/prevention & control , Disease Models, Animal , Hypoxia/complications , Hypoxia-Ischemia, Brain/metabolism , Hypoxia-Ischemia, Brain/pathology , I-kappa B Proteins/metabolism , Injections, Intraventricular , Lipoxins/administration & dosage , Male , NF-kappa B/metabolism , Neurons/drug effects , Neurons/metabolism , Neuroprotective Agents/administration & dosage , Oxidative Stress/drug effects , Primary Cell Culture , Rats , Rats, Sprague-Dawley
15.
J Endod ; 46(4): 531-538, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32081458

ABSTRACT

INTRODUCTION: The suitability of EndoSequence BC Sealer (BC Sealer; Brasseler USA, Savannah, GA) for warm vertical compaction has been questioned. The aim was to evaluate the cytotoxicity and the effect of heating on the physicochemical properties of a new calcium-based root canal sealer (EndoSequence BC Sealer HiFlow [HiFlow]) in comparison with EndoSequence BC Sealer. METHODS: Human periodontal ligament fibroblasts were incubated for 1, 2, or 3 days with material extracts of different concentrations, and cell viability was evaluated by Cell Counting Kit-8 (Enzo Life Sciences Inc, Burlington, Ontario, Canada). The setting time, flow, film thickness, microhardness, radiopacity, and radiopacity of the 2 sealers were measured according to ISO 6786/2012. The continuous changes in viscosity were tested by a stress-controlled rheometer at shear rates ranging from 0.01-10 s-1 and different temperatures, and chemical composition was assessed by Fourier-transform infrared spectroscopy. RESULTS: Cell viability was significantly decreased on day 3 for the 1:4 diluted extract from both materials. The setting time, microhardness, and solubility of HiFlow were similar to BC Sealer at 37°C and 100°C. HiFlow had significantly higher flow and radiopacity than BC Sealer at room temperature (P < .05), and when heated, HiFlow retained its higher flow and lower film thickness (P < .05). Both sealers showed decreasing viscosity with increasing shear rate, and at a shear rate of 0.01 and 0.1 s-1, HiFlow exhibited lower viscosity than BC Sealer at all temperatures measured. The chemical composition of the 2 sealers was not changed by heating. CONCLUSIONS: HiFlow showed better performance on flow/viscosity and film thickness, especially under high temperatures, which are generated by the commonly used warm vertical compaction technique.


Subject(s)
Root Canal Filling Materials , Calcium Compounds , Dental Pulp Cavity , Epoxy Resins , Humans , Materials Testing , Ontario , Silicates , Temperature
16.
Aust Endod J ; 46(1): 11-16, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31605428

ABSTRACT

Pulpal calcifications can present problems in endodontic treatment. This micro-CT study examined the removal of calcifications by a multisonic cleaning system in uninstrumented mandibular molar distal canals. The teeth were accessed and distal canals located and their patency ensured. Micro-CT images were obtained, and 15 teeth with distal canal calcifications were selected. The volume of distal canals and calcifications were calculated from the micro-CT images before and after cleaning with the GentleWave system. Calcifications were observed in all thirds of the canals. Attached and free calcification were detected. Root canal volumes were slightly increased after GentleWave treatment, whereas the calcifications were completely or partially removed in all canals. Mean reduction percentage of calcification was 86.4 ± 3.9%, in individual canals from 60% to 100%. Calcifications in the distal canals of mandibular molars could be partially or completely removed by the multisonic cleaning system without instrumentation.


Subject(s)
Dental Pulp Cavity , Root Canal Preparation , Molar , Root Canal Therapy , X-Ray Microtomography
17.
Front Pharmacol ; 11: 585898, 2020.
Article in English | MEDLINE | ID: mdl-33390957

ABSTRACT

Neonatal hypoxic-ischemic encephalopathy (HIE) is a brain injury caused by perinatal asphyxia and is the main cause of neonatal death and chronic neurological diseases. Protection of neuron after hypoxic-ischemic (HI) brain injury is considered as a potential therapeutic target of HI brain injury. To date, there are no effective medicines for neonatal HI brain injury. Lycopene (Lyc), a member of the carotenoids family, has been reported to have anti-oxidative and anti-inflammatory effects. However, its effects and potential mechanisms in HI brain injury have not yet to be systematically evaluated. In this study, we investigated whether Lyc could ameliorate HI brain injury and explored the associated mechanism both in vivo and in vitro experiments. In vivo study, Lyc significantly reduced infarct volume and ameliorated cerebral edema, decreased inflammatory response, promoted the recovery of tissue structure, and improved prognosis following HI brain injury. In vitro study, results showed that Lyc reduced expression of apoptosis mediators in oxygen-glucose deprivation (OGD)-induced primary cortical neurons. Mechanistically, we found that Lyc-induced Nrf2/NF-κB pathway could partially reversed by Brusatol (an Nrf2 inhibitor), indicated that the Nrf2/NF-κB pathway was involved in the therapy of Lyc. In summary, our findings indicate that Lyc can attenuated HI brain injury in vivo and OGD-induced apoptosis of primary cortical neurons in vitro through the Nrf2/NF-κB signaling pathway.

18.
Nanoscale ; 11(9): 3968-3978, 2019 Feb 28.
Article in English | MEDLINE | ID: mdl-30768095

ABSTRACT

GeSe is considered as a potential absorber material for thin film solar cells owing to its ideal band gap, strong light absorption, remarkable air durability, Earth-abundance and non-toxic constituents. However, the high vapor pressure of GeSe at a temperature below its melting point makes it difficult to synthesize a high-quality GeSe film. To alleviate this limitation, in this work, a thermal evaporation combining a novel sandwiching post-annealing method was introduced to deposit high quality GeSe thin films with (100)-orientation. The self-assembling mechanism of the highly oriented GeSe film was carefully investigated by the systematic experiments and confirmed by the lowest total energy of the (100) crystal plane. Finally, the fully-inorganic, low-cost and non-toxic planar device with the superstrate configuration of FTO/TiO2/GeSe/carbon/Ag was also successfully fabricated. Notably, as a result, an impressive open circuit voltage (VOC) of 340 mV (maximum: 456 mV) was achieved, which is the highest VOC of GeSe solar cells reported so far. Furthermore, through current-voltage, capacitance-voltage profiling and drive level capacitance profiling measurements, it was demonstrated that the limiting factors of the GeSe solar cell performance were the narrow depletion width (138 nm) and the drastic recombination at the TiO2/GeSe interface.

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