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1.
Ann Vasc Surg ; 99: 82-88, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37952569

RESUMO

BACKGROUND: To evaluate the midterm clinical efficacy of paclitaxel drug-coated balloons (DCBs) in the treatment of femoral artery TransAtlantic Inter-Society Consensus (TASC) grades C/D lesions. METHODS: The clinical data of 73 cases with TASC grades C/D lesions of femoral artery treated with paclitaxel DCBs at the Department of Vascular Surgery, the First Hospital of Fujian Medical University from August 2016 to January 2020 were retrospectively analyzed. The primary endpoint was the primary patency rate. The secondary endpoints were freedom from reintervention, Rutherford classification, ankle-brachial index (ABI), amputation events, and all-cause death. RESULTS: A total of 73 cases of limb lesions received endoluminal treatment. The mean age of the patients including 49 males and 24 females was (72.66 ± 11.1) years, with an initial Rutherford classification of 2-5 and an ABI of 0.4 ± 0.1. The mean Rutherford classification was 3.70 ± 0.95. The mean lesion length was (25.75 ± 9.67) cm, including 61.64% chronic occlusive lesions and 27.39% stenotic lesions, the remaining 10.97% were mixed lesions, containing multiple segments of stenosis and chronic total occlusion lesions. 43.8% of the lesions were associated with severe calcification. Stent implantation rate was 8%. Overall mortality at follow-up was 4% at 1 year and 8% at 2 years, and no amputations seen. The ABI was 0.83 ± 0.07 at 1-year follow-up and 0.78 ± 0.05 at 2-year follow-up. The Kaplan-Meier survival curve predicted the 1-year phase I patency rate was 75.3% ± 5% and the 2-year patency rate was 63.3% ± 5.7%. Freedom from target lesion revascularization was 78.4 ± 4.9% at 1 year and 69.2% ± 3.6% at 2 years. Logistic regression analysis showed that diabetes mellitus, severe calcification, chronic renal insufficiency, and restenosis were the significant factors affecting the patency of target lesions. CONCLUSIONS: Paclitaxel DCBs in the treatment of femoral artery with TASC grades C/D lesions can achieve relatively satisfactory midterm clinical safety and efficacy results, provided there is an acceptable result on completion angiogram.


Assuntos
Angioplastia com Balão , Doença Arterial Periférica , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia , Doença Arterial Periférica/etiologia , Angioplastia com Balão/efeitos adversos , Stents , Paclitaxel/efeitos adversos , Grau de Desobstrução Vascular
2.
Planta ; 257(5): 85, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36944703

RESUMO

MAIN CONCLUSION: PPO was purified from Cistanche deserticola, and its enzymatic characteristics were clarified. It was found that microwave treatment was an efficient way to inactivate PPO. Polyphenol oxidase (PPO) from Cistanche deserticola was obtained and purified through an acetone precipitation and anion exchange column, the enzymatic characteristics and inactivation kinetics of PPO were studied. The specific activity of PPO was 73135.15 ± 6625.7 U/mg after purification, the purification multiple was 48.91 ± 4.43 times, and the recovery was 30.96 ± 0.27%. The molecular weight of the PPO component is about 66 kDa by SDS-PAGE analysis. The optimum substrate of PPO was catechol (Vmax = 0.048 U/mL, Km = 21.70 mM) and the optimum temperature and pH were 30 °C and 7, respectively. When the temperature is above 50 °C, pH < 3 or pH > 10, the enzyme activity can be significantly inhibited. The first-order kinetic fitting shows that microwave inactivation has lesser k values, larger D values and shorter t1/2. It was found that microwave treatment is considered as an efficient and feasible way to inactive PPO by comparing the Z values and Ea values of the two thermal treatments.


Assuntos
Cistanche , Cistanche/metabolismo , Catecol Oxidase/química , Catecol Oxidase/metabolismo , Cinética , Temperatura , Peso Molecular , Concentração de Íons de Hidrogênio
3.
J Cell Physiol ; 234(5): 6611-6623, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30230544

RESUMO

Chloride channel-3 (ClC-3), a member of the ClC family of voltage-gated Cl- channels, is involved in the resistance of tumor cells to chemotherapeutic drugs. Here, we report a new mechanism for ClC-3 in mediating multidrug resistance (MDR). ClC-3 was highly expressed in the P-glycoprotein (P-gp)-dependent human lung adenocarcinoma cell line (A549)/paclitaxel (PTX) and the human breast carcinoma cell line (MCF-7)/doxorubicin (DOX) resistant cells. Changes in the ClC-3 expression resulted in the development of drug resistance in formerly drug-sensitive A549 or MCF-7 cells, and drug sensitivity in formerly drug-resistant A549/Taxol and MCF-7/DOX cells. Double transgenic MMTV-PyMT/CLCN3 mice with spontaneous mammary cancer and ClC-3 overexpression demonstrated drug resistance to PTX and DOX. ClC-3 expression upregulated the expression of MDR1 messenger RNA and P-gp by activating the nuclear factor-κB (NF-κB)-signaling pathway. These data suggest that ClC-3 expression in cancer cells induces MDR by upregulating NF-κB-signaling-dependent P-gp expression involving another new mechanism for ClC-3 in the development of drug resistance of cancers.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Neoplasias da Mama/metabolismo , Canais de Cloreto/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Células MCF-7 , NF-kappa B/metabolismo , Ativação Transcricional/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia
4.
J Asian Nat Prod Res ; 19(8): 793-802, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27848262

RESUMO

In this paper, 17 compounds (1-17) were isolated from the leaves of Hemp (Cannabis sativa f. sativa). Among the isolates, two were determined to be new spirans: cannabispirketal (1), and α-cannabispiranol 4'-O-ß-D-glucopyranose (2) by 1D and 2D NMR spectroscopy, LC-MS, and HRESIMS. The known compounds 7, 8, 10, 13, 15, and 16 were isolated from Hemp (C. sativa f. sativa) for the first time. Furthermore, compounds 8 and 13 were isolated from the nature for the first time. All isolated compounds were evaluated for cytotoxicity on different tissue-derived passage cancer cell lines through cell viability and apoptosis assay. Among these compounds, compounds 5, 9 and 16 exhibited a broad-spectrum antitumor effect via inhibiting cell proliferation and promoting apoptosis. These results obtained have provided valuable clues to the understanding of the cytotoxic profile for these isolated compounds from Hemp (C. sativa f. sativa).


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Cannabis/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Folhas de Planta/química , Compostos de Espiro/isolamento & purificação , Antineoplásicos Fitogênicos/química , Apigenina , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Flavonas , Flavonoides/química , Humanos , Células MCF-7 , Estrutura Molecular , Compostos de Espiro/química
5.
Opt Express ; 22(17): 20924-35, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-25321293

RESUMO

We present a detailed characterization of enhanced 2.0 µm emission and energy transfer processes by codoping Ce3+ in ZBYA: Ho3+/Er3+ glasses under 1550 nm excitation. The measured absorption and emission spectra show that Er3+ ions are efficiently excited by pumping and energy transfer from Er3+: 4I13/2 to Ho3+: 5I7 level. The 2.0 µm emission from the Ho3+: 5I7→5I8 transition is enhanced by codoping Ce3+ (< 0.5 mol %) ions in the Ho3+/Er3+ doped glasses. However, excess Ce3+ ions in the glass network negatively affect the mid-infrared emission. The upconversion luminescence is dominated by Er3+ (667 nm) red emission in the Ho3+/Er3+ doped sample, which is suppressed after introducing Ce3+ ions. The red emission is abnormally dominated by the Ho3+ (650 nm) emission when the ratio of the three ions (Ho3+/Er3+: Ce3+) is 1:1:0.5. These results indicate that Ce3+ ions can enhance Ho3+: 2.0 µm emission by suppressing the upconversion processes. The Ho3+/Er3+/Ce3+ triply-doped ZBYA glass is a promising material for 2.0 µm fiber laser applications.

6.
Opt Lett ; 39(20): 5917-20, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25361119

RESUMO

This work reports the intense emissions at 2.7 and 2.84 µm in a Ho³âº/Er³âº-codoped fluoride glass (ZrF4-BaF2-YF3-AlF3). An extensive transmission spectrum and the absence of strong OH⁻ absorption guarantee the observation of mid-infrared (IR) emissions. For the Ho³âº/Er³âº-codoped sample, the 2.7- and 2.84-µm emissions are 5.8 and 3.8 times higher with larger emission cross-sections (10.2×10⁻²¹ and 9.8×10⁻²¹ cm²), respectively. Meanwhile, other near to middle infrared emissions (1200, 2045 nm emissions from Ho³âº and 980, and 1535 nm emissions from Er³âº ions) are all enhanced. The collective enhanced effect originates from the disappearance of nonradiative decay processes after codping Er³âº and Ho³âº ions. Hence, the advantageous spectroscopic characteristics of Ho³âº/Er³âº-codoped ZBYA glass indicate that this kind of fluoride glass may be an attractive host to develop solid-state lasers for 3 µm.

7.
Opt Lett ; 39(7): 1772-4, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24686601

RESUMO

The room-temperature Stark splitting properties of Yb3+ are practical and valuable for lasers because the working temperature of the gain media intensively increases with the laser output. In this Letter, the room-temperature Stark splitting properties of Yb3+ in several popular laser glasses are contrastively studied. Yb3+-doped germanate (Ge), borate (B), silicate (Si), bismuthate (Bi), tellurite (Te), and fluorophosphate (FP) glasses exhibit large Stark splitting and tend to operate close to the quasi-four-level scheme, whereas phosphate (P) glass shows the weakest Stark splitting and tends to operate close to the quasi-three-level one. Due to the low thermal conductivity of the glass matrix, Yb3+-doped P glass suffers from serious thermal problems and is difficult to achieve high laser output. The Stark splitting is also used to estimate the crystal-field strength of glass hosts and local Yb3+ ligand asymmetry degree. The results show that P glass shows weaker crystal-field effect and lower Yb3+ ligand asymmetry than Ge, Si, and B glasses.

8.
Mol Biol Rep ; 41(11): 7241-54, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25063579

RESUMO

Epidemiological studies have reported the relationship between vacuolating cytotoxin A (vacA) s-/m- region genotypes and duodenal ulcer (DU), but the results remained inconclusive. We performed the present meta-analysis to investigate a more authentic association between vacA s-/m- region genotypes and DU. Literature search was performed by searching Embase, PubMed and ISI Web of Science databases as well as checking references from identified articles, reviews and the abstracts presented at related scientific societies meetings. The association was assessed by combined odds ratio (OR) with 95% confidence interval (CI). A total of 42 studies were included in our final meta-analysis. The combined ORs (95% CIs) showed that vacA s1 (OR = 2.96, 95% CI = 2.34-3.75), m1 (OR = 1.46, 95% CI = 1.05-2.04) and s1m1 (OR = 1.89, 95% CI = 1.47-2.42) were associated with increased DU risk significantly in the overall studied population. Subgroup analyses by ethnicity showed that vacA s1 increased the risk of DU in Asian countries (OR = 1.92, 95% CI = 1.30-2.83), European countries (OR = 3.58, 95% CI = 2.13-6.03) and Latin American countries (OR = 4.20, 95% CI = 2.21-7.98); vacA m1 increased the risk of DU in Latin American countries (OR = 2.98, 95% CI = 1.59-5.56); vacA s1m1 increased the risk of DU in Asian countries (OR = 2.04, 95% CI = 1.12-3.73) and Latin American countries (OR = 2.05, 95% CI = 1.20-3.48); vacA s2m1 increased the risk of DU in Latin American countries (OR = 2.30, 95% CI = 1.17-4.50). The data suggest that genotype testing of vacA s- and m- region will be useful in screening susceptible individuals for DU development.


Assuntos
Proteínas de Bactérias/genética , Úlcera Duodenal/epidemiologia , Úlcera Duodenal/microbiologia , Helicobacter pylori/patogenicidade , Biologia Computacional , Estudos de Associação Genética , Helicobacter pylori/genética , Humanos , Razão de Chances , Fatores de Risco
9.
Food Chem X ; 22: 101269, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38495456

RESUMO

In recent years, the production of prepared and frozen foods has increased with economic development. However, during freezing, moisture migration forms ice crystals that damage food structure and reduce quality. This study investigates moisture migration changes in pre-fermented dough during frozen storage and effectiveness of Citrus fibre (CF) and Soya dietary fibre (SDF) on quality improvement. Pre-fermented frozen dough properties were evaluated at different freezing storage days with CF and SDF. Results showed frozen storage reduced water retention, converting deeply bound water to weakly bound and free water. Freezable water content increased significantly from 53% (fresh) to 56.95% (60d-control), forming disruptive ice crystals in gluten protein structure. SDF had superior water flow restriction compared to CF, preventing large ice crystal accumulation, enhancing water-holding capacity, and maintaining gluten protein structure. These findings lay a theoretical foundation for improving quality and industrial applications of pre-fermented frozen dough.

10.
J Vasc Surg Venous Lymphat Disord ; : 101945, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38972545

RESUMO

OBJECTIVE: This study aimed to evaluate the effectiveness and safety of coils plus glue in slope embankment technology versus coils plus sclerosant in treating reflux-type pelvic venous disorders. METHODS: The analysis included patients diagnosed with reflux-type pelvic venous disorders who were treated with coils plus glue (CPG) or coils plus sclerosant (CPS) from 2019 to 2021. The inclusion criteria were non-cyclic pain lasting more than 6 months, atypical varicose, and transvaginal Doppler ultrasonography (TVDUS) and computed tomographic venography(CTV) confirming the diagnosis and excluding compression factors and other diseases. Propensity score matching was performed at a 1:1.1 ratio based on the following covariates: age, pregnancy, BMI, pretreatment VAS, dysmenorrhea, dyspareunia, urinary urgency, tenesmus, low back pain, vulvar varicosities, vaginal varicosities and lower limb varices. The pain was relieved by embolizing the target lesions with different embolic materials. The efficacy and safety of the different embolization materials were compared by visual analog scale (VAS) and TVDUS examinations at 1, 3, 6, 12, 24, and 36 months. RESULTS: From a total of 495 patients, 88 patients were selected from the CPG group and 77 patients from the CPS group by propensity score matching. The patients were followed up for 36 months. The preoperative VAS score of the Coils Plus Glue(CPG)group was 8 (range 6-8), and the Coils Plus Sclerosant(CPS) score was 8 (range 7-8),P=0.64. The post-embolization VAS score of the CPG group was 2.05±0.37, and the CPS score was 2.14±0.35(P=0.55). A total of 28 cases (16.9%) showed complications, most of which were transient pain after embolization. No serious complications such as coil embolization to the lungs occurred. In addition, the CPG group used fewer coils than the CPS group by using the Slope Embankment Technique(SET) . The mean coil length of the CPG group was 77.18±33.82 cm, and the CPS group was 105.29±71 cm(P=0.001). The CPG group had an average operation time of 44.49±5.72 min, while the CPS group took 43.45±4.18 min on average(P=0.19). The radiation dose of the CPG group was 398.40±76.16mGy, and the radiation dose of the CPS group was 388±44.23mGy(P=0.30). The median recurrence free survival(RFS) of the CPG group was 34.23 months (95% CI 33.2-35.2), and the median RFS of the CPS group was 30.39 months (95% CI 28.2-32.6), LogRank=0.018. CONCLUSIONS: Embolization therapy for refluxing PeVD was safe and effective, and proficient use of SET with coils plus glue increased efficacy and reduced complications.

11.
Foods ; 12(22)2023 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-38002162

RESUMO

Slightly acidic electrolytic water (SAEW) treatment for seed germination is a promising technique for sustainable agriculture. This study investigated the antioxidant activity of germinated sesame seeds treated with SAEW for the first time. Specifically, the impact and correlation of SAEW on the activities of total phenols, total flavonoids, and antioxidant oxidase in sesame seeds were examined. The results showed that SAEW with low ACC inhibited sesame germination, SAEW with high ACC promoted sesame germination, and sesame buds treated with SAEW with 30 mg/L and 50 mg/L ACC showed lower antioxidant activity and total phenolic and flavone content compared to tap water. In contrast, SAEW with 30 mg/L ACC had no significant effect on sesame growth but positively influenced the antioxidant activity of sesame seed germination by promoting phenolic compound synthesis through increased phenylalanine ammonia-lyase (PAL) activity and enhancing antioxidant activity by boosting PAL, polyphenol oxidase (PPO), and peroxidase (POD) activities. Generally, antioxidant ability was the most prominent in SAEW with 30 mg/L ACC, and positive correlations between antioxidation and total phenols and flavonoids content were found in sesame. These findings provide valuable insights into the mechanisms underlying the enhanced antioxidant capacity observed in germinated sesame seeds under SAEW stress.

12.
J Proteomics ; 286: 104952, 2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37390895

RESUMO

Acidic electrolyzed water is a relatively mature bactericide, which has a certain inhibitory effect on a variety of microorganisms, and is widely used in the field of food processing for cleaning, sterilization and disinfection. This study investigated the deactivation mechanisms of Listeria monocytogenes by Tandem Mass Tags quantitative proteomics analysis. Samples were treated through A1S4 (Alkaline electrolytic water treatment for 1 min and Acid electrolytic water treatment for 4 min), S3A1S1 (Acid electrolyzed water treatment 3 min, Alkaline electrolyzed water treatment 1 min and Acid electrolyzed water treatment 1 min), S5 (Acid electrolytic water treatment for 5 min). Proteomic analysis showed that the mechanism of acid alkaline electrolyzed water treatment to eliminate the inactivation of the biofilm of L. monocytogenes was related to protein transcription and extension, RNA processing and synthesis, gene regulation, sugar and amino acid transport and metabolism, signal transduction and ATP binding. The study on the influence mechanism and action mechanism of the combination of acidic and alkaline electrolyzed water to remove L. monocytogenes biofilm is helpful to understand the development of the process of removing biofilm by electrolyzed water, and provides theoretical support for the treatment of other microbial contamination problems in food processing by electrolyzed water.


Assuntos
Microbiologia de Alimentos , Listeria monocytogenes , Listeria monocytogenes/fisiologia , Proteômica , Contagem de Colônia Microbiana , Biofilmes , Álcalis/farmacologia
13.
Zhonghua Gan Zang Bing Za Zhi ; 20(7): 537-41, 2012 Jul.
Artigo em Zh | MEDLINE | ID: mdl-23044241

RESUMO

OBJECTIVE: To investigate the effects of magnesium isoglycyrrhizinate (MI) on the changes of phospholipase A2 (PLA2) induced during liver tissue injury following limb ischemia/reperfusion (I/R) in rats. METHOD: Twenty-four healthy male Sprague-Dawley rats weighing (230+/-30) g were randomly divided into three groups (n = 8 each) as follows: control (Group C: anesthetization without any ischemia); I/R injury (Group I/R: 4 h ischemia induced by rubber band ligation of the left hind limb around the roots of the hind limb, followed by 6 h of reperfusion, with 1 mL normal saline given via tail vein prior to reperfusion); MI-treated group (Group MI: underwent ischemia and reperfusion, with 1 mL MI (30 mg/kg) infused prior to reperfusion). Levels of TNFa and PLA2 in plasma and liver tissue were measured by enzyme-linked immunosorbent assay (ELISA). Levels of plasma alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine kinase (CK), myeloperoxidase (MPO), and malondialdehyde (MDA), and activities of MPO and MDA in liver tissue were measured by colorimetry. Ultrastructural changes of liver tissue were observed by electron microscopy. RESULTS: The MI group had significantly lower PLA2 and TNFa in liver homogenates and serum than the I/R group (both P less than 0.05). Serum ALT, AST, LDH, and CK were significantly lower in the MI group than in the I/R group (all P less than 0.05), as were the levels of MPO and MDA in liver homogenates and serum (all P less than 0.05). The I/R group showed significantly more liver tissue damage, which appeared to be attenuated in the MI group. CONCLUSION: MI treatment can inhibit the I/R-induced TNFa, PLA2, and MDA in plasma and liver tissue, as well as decrease the I/R-induced MPO activity in rats. Thus, MI may have protective effects against liver tissue injury following limb ischemia/reperfusion.


Assuntos
Fígado/metabolismo , Fosfolipases A2/metabolismo , Traumatismo por Reperfusão/metabolismo , Saponinas/farmacologia , Triterpenos/farmacologia , Animais , Extremidades/irrigação sanguínea , Fígado/efeitos dos fármacos , Fígado/lesões , Masculino , Malondialdeído/metabolismo , Ratos , Ratos Sprague-Dawley
14.
Foods ; 11(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36553813

RESUMO

This study investigated the broad-spectrum bactericidal activity of non-electrolytic hypochlorite water (NEHW) and detected its hydroxyl radical content compared with that of slightly acidic electrolytic water (SAEW). Based on the results of UV scanning and storage stability, higher hypochlorite content and stronger oxidation were found to be responsible for the stronger bactericidal effect of NEHW. NEHW can achieve 99% bacterial disinfection effect by treating with 10 mg/L available chlorine concentration for more than 5 minutes. At the same time, the storage stability of NEHW was higher than that of SAEW. After 20 days of storage under sealed and dark conditions, the pH value only increased by 7.9%, and the effective chlorine concentration remained nearly 80%. The results showed that NEHW had higher germicidal efficacy and storage stability than SAEW.

15.
Artigo em Inglês | MEDLINE | ID: mdl-36308398

RESUMO

High-performance thermal insulating materials are highly desirable in several fields, especially for thermal insulation of buildings to reduce energy consumption. Owing to the remarkable thermal stability, high porosity, low density, and outstanding mechanical features, polyimide (PI) aerogels have attracted great attention. In this work, chemical cross-linked PI (CCPI) aerogels were fabricated via freeze-drying and thermal imidization, which possess outstanding mechanical properties, good thermal stability, and excellent thermal insulation characteristics. The chemically cross-linked structure can effectively inhibit shrinkage, while retaining the structural integrity, resulting in the lower density and lower shrinkage of the materials. In this paper, completely imidized and highly cross-linked polyimide aerogels were synthesized by using p-phenylenediamine (PDA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), and the cross-linker 2,3,6,7,14,15-hexaaminotriptycene (HMT). The CCPI aerogels with excellent properties, such as covalently cross-linked chemical structure, low density (0.069 g/cm3), low volume shrinkage (10%), high decomposition temperature (Td5% = 587 °C), and low thermal conductivity (25 mW m-1K-1) are in high demand in the field of thermal insulation. This work furnishes a new method for the development of polymer-based thermal insulation materials for various prospective applications.

16.
J Colloid Interface Sci ; 628(Pt A): 247-258, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35932664

RESUMO

Rational design of separators is especially critical to solve the "shuttle effect" of lithium polysulfides (LiPSs) and the sluggish redox kinetics in lithium-sulfur batteries (LSBs). Here, the multi-functional nanocomposite involving Co-doped molybdenum phosphide (Co-MoP) nanofibers and porous carbon nanofibers (PCNFs) is designed and prepared through electro-blow spinning and phosphating process, which possesses multiple adsorption and catalytic sites and is acted as the functional material for LSBs separators. In this multifunctional nanocomposite, the prepared Co-MoP nanofibers can provide internal adsorption and catalytic sites for LiPSs conversion. And the interconnected nitrogen-doped PCNFs can be elaborated an efficient LiPSs mediator and accommodate the huge volume changes in the reaction process for LSBs. Benefiting from the multiple adsorptive and catalytic sites of the developed functional materials, the assembled LSBs with a Co-MoP/PCNFs modified separator display outstanding electrochemical performances, including an admirable capacity retention of 770.4 mAh g-1 after 400 cycles at 1.0 C, only 0.08 % capacity decay per cycle at 2.0 C, rate performance up to 5 C, and also decent areal capacity even under a high sulfur loading of 4.9 mg cm-2. The work provides a facile pathway towards multifunctional separators in LSBs, and it may also help deepen preparation method of MoP through the electrostatic blowing/electrospinning technology in other related energy storage fields.

17.
Sci Rep ; 11(1): 16295, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381068

RESUMO

With the aim for a low-aspect-ratio flying wing configuration, this study explores the influence of wall temperature gradient on the laminar and turbulent boundary layers of aircraft surface and determines the effect on the transition Reynolds number and wall friction drag. A four-equation turbulence model with transition mode is used to numerically simulate the flow around the model. The variation of wall friction coefficient, transition Reynolds number, and turbulent boundary layer flow with wall temperature are emphatically investigated. Results show that when the wall temperature increases from 288 to 500 K, the boundary layer transition Reynolds number for the wing section increased by approximately 28% and the surface friction drags decreases by approximately 10.7%. The hot wall enhances the viscous effects of the laminar temperature boundary layer, reduces the Reynolds shear stress and turbulent kinetic energy, and increases the flow stability. However, the velocity gradient and shear stress in the bottom of the turbulent boundary layer decreases, which leads to reduced friction shear stress on the wall surface. Therefore, for the low-aspect-ratio flying wing model, the hot wall can delay the boundary layer transition and reduce the friction drag coefficient in the turbulent region.

18.
Int J Biol Macromol ; 168: 223-232, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33309660

RESUMO

A novel thermostable xylanase gene from Chaetomium sp. CQ31 was cloned and codon-optimized (CsXynBop). The deduced protein sequence of the gene shared the highest similarity of 75% with the glycoside hydrolase (GH) family 10 xylanase from Achaetomium sp. Xz-8. CsXynBop was over-expressed in Pichia pastoris GS115 by high-cell density fermentation, with the highest xylanase yield of 10,017 U/mL. The recombinant xylanase (CsXynBop) was purified to homogeneity and biochemically characterized. CsXynBop was optimally active at pH 6.5 and 85 °C, respectively, and stable over a broad pH range of 5.0-9.5 and up to 60 °C. The enzyme exhibited strict substrate specificity towards oat-spelt xylan (2, 489 U/mg), beechwood xylan (1522 U/mg), birchwood xylan (1067 U/mg), and showed relatively high activity towards arabinoxylan (1208 U/mg), but exhibited no activity on other tested polysaccharides. CsXynBop hydrolyzed different xylans to yield mainly xylooligosaccharides (XOSs) with degree of polymerization (DP) 2-5. The application of CsXynBop (200 U/g malt) in malt mashing substantially decreased the filtration time and viscosity of malt by 42.3% and 8.6%, respectively. These excellent characteristics of CsXynBop may make it a good candidate in beer industry.


Assuntos
Chaetomium/enzimologia , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/isolamento & purificação , Sequência de Aminoácidos , Cerveja/microbiologia , Chaetomium/genética , Chaetomium/metabolismo , Clonagem Molecular/métodos , Estabilidade Enzimática , Glucuronatos , Glicosídeo Hidrolases/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Peso Molecular , Oligossacarídeos , Especificidade por Substrato , Xilanos/química , Xilanos/metabolismo
19.
ACS Appl Mater Interfaces ; 13(18): 21286-21298, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33904728

RESUMO

A superflexible hydrophobic silica-based aerogel (FHSA) was prepared via a facile sol-gel process and ambient pressure drying method. The FHSA was treated at different temperatures varying from -196 to 450 °C to evaluate its thermal and mechanical performances. The evolutions of the physical property, hydrophobicity, microstructure, pore structure, and chemical structure of the FHSA with the various treatment temperatures were investigated comprehensively. The structure of the FHSA did not show an obvious change after treatment in the liquid nitrogen. The bulk density of the FHSA increased from 0.047 to 0.077 g cm-3 when the thermal treatment temperature increased from 25 to 450 °C. The specific surface area and pore volume of the FHSA increased with the treatment temperature owing to the decomposition of the organic moieties. The Fourier transform infrared spectra showed that the methyl groups in the FHSA had excellent thermostability up to 400 °C. The water contact angles of the FHSA after treatment at -196, 25, 200, 300, 350, 400, and 450 °C were 131, 151, 162, 150, 132, 119, and 34°, respectively. The thermal conductivity of the FHSA at a low temperature of -10 °C was 0.022 W m-1 K-1. The reversible deformation rate of the FHSA was more than 80% within 100 compression cycles. After treatment in liquid nitrogen, the reversible deformation rate of the FHSA remained at 50%. The synthesis method of the FHSA is simple, the resulting FHSA showed good performance both in thermostability and flexibility, and it is promisingly applied for thermal insulation and sealing in ultralow-temperature environments.

20.
Naunyn Schmiedebergs Arch Pharmacol ; 393(3): 501-510, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31659404

RESUMO

5-Nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB) is a non-specific chloride channel blocker. Peritoneal adhesion is an inevitable complication of abdominal surgery and remains an important clinical problem, leading to chronic pain, intestinal obstruction, and female infertility. The aim of this study is to observe the effects of NPPB on peritoneal adhesions and uncover the underlying mechanism. The formation of postoperative peritoneal adhesions was induced by mechanical injury to the peritoneum of rats. MTT assay and wound-healing assay were used to evaluate proliferation and migration of primary cultured adhesion fibroblasts (AFB) respectively. Whole-cell chloride currents were measured using a fully automated patch-clamp workstation. Cell volume changes were monitored by light microscopy and video imaging. Our results demonstrated that NPPB could significantly prevent the formation of peritoneal adhesion in rats and inhibit the proliferation of AFB in a concentration-dependent manner. NPPB also reduced the migration of AFB cells with an IC50 of 53.09 µM. A 47% hypotonic solution successfully activated the ICl,vol in AFB cells. The current could be blocked by extracellular treatment with NPPB. Moreover, 100 µM NPPB almost completely eliminated the capacity of regulatory volume decrease (RVD) in these cells. These data indicate that NPPB could prevent the formation of postoperative peritoneal adhesions. The possible mechanism may be through the inhibition of the proliferation and migration of AFB cells by modulating ICl,vol and cell volume. These results suggest a potential clinical use of NPPB for preventing the formation of peritoneal adhesions.


Assuntos
Movimento Celular/efeitos dos fármacos , Canais de Cloreto/antagonistas & inibidores , Nitrobenzoatos/uso terapêutico , Peritônio/efeitos dos fármacos , Complicações Pós-Operatórias/tratamento farmacológico , Aderências Teciduais/tratamento farmacológico , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Movimento Celular/fisiologia , Células Cultivadas , Canais de Cloreto/fisiologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Nitrobenzoatos/farmacologia , Peritônio/fisiopatologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Ratos , Ratos Sprague-Dawley , Aderências Teciduais/etiologia , Aderências Teciduais/fisiopatologia
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