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1.
Angew Chem Int Ed Engl ; 63(10): e202318564, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38230985

RESUMO

Photoinduced 3D printing based on the reversible addition-fragmentation chain transfer (RAFT) process has emerged as a robust method for creating diverse functional materials. However, achieving precise control over the mechanical properties of these printed objects remains a critical challenge for practical application. Here, we demonstrated a RAFT step-growth polymerization of a bifunctional xanthate and bifunctional vinyl acetate. Additionally, we demonstrated photoinduced 3D printing through RAFT step-growth polymerization with a tetrafunctional xanthate and a bifunctional vinyl acetate. By adjusting the molar ratio of the components in the printing resins, we finely tuned the polymerization mechanism from step-growth to chain-growth. This adjustment resulted in a remarkable range of tunable Young's moduli, ranging from 7.6 MPa to 997.1 MPa. Moreover, post-functionalization and polymer welding of the printed objects with varying mechanical properties opens up a promising way to produce tailor-made materials with specific and tunable properties.

2.
Small ; 19(2): e2205219, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36404124

RESUMO

Lightweight and impact-resistant materials with self-monitoring capability are highly desired for protective applications, but are challenging to be artificially fabricated. Herein, a scalable-manufactured aramid nanofiber (ANF)-based composite combining these key properties is presented. Inspired by the strengthening and toughening mechanisms relying on recoverable interfaces commonly existing in biological composites, mechanically weak but dense hydrogen bonds are introduced into the ANF interfaces to achieve simultaneously enhanced tensile strength (300 MPa), toughness (55 MJ m-3 ), and impact resistance of the nanofibrous composite. The achieved mechanical property combination displays attractive advantages compared with that of most of previously reported nanocomposites. Additionally, the nanofibrous composite is designed with a capability for real-time self-monitoring of its structural safety during both quasi-static tensile and dynamic impact processes, based on the strain/damage-induced resistance variations of a conductive nanowire network inside it. These comprehensive properties enable the present nanofibrous composite with promising potential for protective applications.


Assuntos
Nanofibras , Nanofibras/química , Resistência à Tração
3.
Chemphyschem ; 22(16): 1675-1683, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34142761

RESUMO

The unique physical structure and abundant surface functional groups of MXene make the grafted organic molecules exhibit specific electrical and optical properties. This work reports the results of first-principles calculations to investigate the composite systems formed by different organic molecular monomers, namely acrylic acid (AA), acrylamide (AM), 1-aziridineethanol (1-AD) and glucose, and Ti3 C2 MXene saturated with different functional groups, namely -OH, -O and -F. The results show that the interaction between organic molecules and the MXene surface depends on the type of functional groups of the organic molecules, while the strength of the interaction is determined by the type of surface functional groups and the number of hydrogen bonds. The bare Ti3 C2 and Ti3 C2 (OH)2 can readily form strong chemical and hydrogen bonds with AA and AM molecules, leading to strong adsorption energy and a large amount of charge transfer, while the interaction between organic molecules and MXene saturated by -F or -O groups mainly exhibits physical interactions, accompanied by low adsorption energy and a small amount of charge transfer. This research provides theoretical guidance for the synthesis of high-performance MXene organic composite systems.

4.
Mediators Inflamm ; 2021: 8481013, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803518

RESUMO

Exosomes are membrane-bound extracellular vesicles that are produced in the endosomal compartment of most eukaryotic cells. Containing proteins, RNA, and DNA, exosomes mediate intercellular communication between different cell types by transferring their contents and thus are involved in numerous physiological and pathological processes. T cells are an indispensable part of adaptive immunity, and the functions of T cell-derived exosomes have been widely studied. In the more than three decades since the discovery of exosomes, several studies have revealed that T cell-derived exosomes play a novel role in cell-to-cell signaling, especially in inflammatory responses, autoimmunity, and infectious diseases. In this review, we will summarize the function of T cell-derived exosomes and their therapeutic potential.


Assuntos
Exossomos/fisiologia , Linfócitos T/ultraestrutura , Linfócitos T CD4-Positivos/ultraestrutura , Linfócitos T CD8-Positivos/ultraestrutura , Humanos , Linfócitos T Reguladores/ultraestrutura
5.
Molecules ; 26(18)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34577134

RESUMO

Solid waste silica fume was used to replace fly ash by different ratios to study the early-age hydration reaction and strength formation mechanism of concrete. The change pattern of moisture content in different phases and micro morphological characteristics of concrete at early age were analyzed by low field nuclear magnetic resonance (LF-NMR) and scanning electron microscope (SEM). The results showed that the compressive strength of concrete was enhanced optimally when the replacement ratio of solid waste silica fume was 50%. The results of LF-NMR analysis showed that the water content of modified concrete increased with the increase of solid waste silica fume content. The compressive strength of concrete grew faster within the curing age of 7 d, which means the hydration process of concrete was also faster. The micro morphological characteristics obtained by SEM revealed that the concrete was densest internally when 50% fly ash was replaced by the solid waste silica fume, which was better than the other contents.

6.
J Clin Pharm Ther ; 45(1): 191-198, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31557362

RESUMO

WHAT IS KNOWN AND OBJECTIVE: As terlipressin becomes more widely used in clinical practice, more papers had reported the correlation between hyponatremia and terlipressin treatment. This study was performed to evaluate the clinical characteristics and risk factors of severe hyponatremia in cirrhotic patients treated with terlipressin and the effects of concomitant drugs. METHODS: We conducted a retrospective evaluation of patients with cirrhosis treated with terlipressin at the gastroenterology department of Hospital between 1 January 2016 and 30 June 2018. Patients treated with terlipressin for gastrointestinal bleeding due to peptic ulcer and other non-hepatic factors were excluded. RESULTS AND DISCUSSION: After the patients received terlipressin, their serum sodium concentrations decreased from 138.2 ± 4.3 mmol/L to 129.3 ± 7.2 mmol/L. Statistically significant differences were observed with respect to sex, initial serum sodium concentration, lowest serum sodium concentration, hyponatremia duration and total drug dose. Among the patients with hyponatremia, statistically significant differences in albumin level, serum creatinine level, hyponatremia duration and total drug dose were found between the patients with severe hyponatremia and those with non-severe hyponatremia. Logistic regression analysis revealed that initial serum sodium concentration (odds ratio, 95% confidence interval: 18.475, 3.967-86.035; P = .000) was a risk factor for reduced serum concentration, and that albumin level (1.105, 1.012-1.207; P = .026), serum creatinine level (0.975, 0.952-0.997; P = .028) and hyponatremia duration (1.297, 1.064-1.583; P = .010) were risk factors of severe hyponatremia. WHAT IS NEW AND CONCLUSION: The incidence of severe hyponatremia among patients with cirrhosis who are treated with terlipressin is high. Moreover, higher initial serum sodium concentrations and increased duration of terlipressin administration are associated with a higher the incidence of severe hyponatremia. The initial albumin level is a risk factor for severe hyponatremia as is serum creatinine, although the latter is negatively correlated with the occurrence of the condition.


Assuntos
Hemorragia Gastrointestinal/tratamento farmacológico , Hiponatremia/etiologia , Cirrose Hepática/tratamento farmacológico , Terlipressina/administração & dosagem , Adulto , Idoso , Creatinina/sangue , Relação Dose-Resposta a Droga , Feminino , Hemorragia Gastrointestinal/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Úlcera Péptica/complicações , Úlcera Péptica/tratamento farmacológico , Estudos Retrospectivos , Fatores de Risco , Albumina Sérica Humana/metabolismo , Sódio/sangue , Vasoconstritores/administração & dosagem
7.
Clin Exp Hypertens ; 41(3): 235-243, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29787310

RESUMO

To determine whether the sympathetic nerve plays a role in the regulation of Na+-H+ exchange (NHE) in the kidney of spontaneously hypertensive rats (SHR), we investigated the expression of NHE and NHE regulatory protein family (NHERF) in the denervated kidneys compared with intact kidneys. Twelve-week-old male SHR and age-matched Wistar Kyoto (WKY) rats were used. SHR were randomly assigned to the renal denervated (RDNX, n = 8) or Sham (n = 8) groups. The protein and mRNA expression of NHE1, NHE3, NHERF1 and NHERF2 were assessed in the kidney of the groups. Following the renal denervation, immunohistochemistry and western blot analysis showed that NHE1 and NHE3 protein were significantly decreased in the kidney compared with Sham group. NHERF1 protein expression was significantly increased in RDNX compared with Sham group, whereas NHERF2 protein expression was significantly decreased after renal denervation. Similar results were observed at the mRNA level of NHE1, NHE3, NHERF1 and NHERF2 expression. The present findings suggest that the renal sympathetic nervous system plays a role in the regulation of NHE1 and NHE3 in the kidney of SHR, and NHERF1 may be involved in the expression of NHE3 in the kidney of SHR.


Assuntos
Hipertensão/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Animais , Rim/inervação , Rim/cirurgia , Masculino , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Trocador 1 de Sódio-Hidrogênio/metabolismo , Trocador 3 de Sódio-Hidrogênio/metabolismo , Simpatectomia/métodos , Sistema Nervoso Simpático/fisiologia
8.
Bioorg Med Chem Lett ; 25(17): 3458-63, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26195136

RESUMO

A series of pyrimidine alkynyl derivatives were designed and synthesized as new Bcr-Abl inhibitors by hybriding the structural moieties from GNF-7, ponatinib and nilotinib. One of the most potent compounds 4e strongly suppresses Bcr-Abl(WT) and Bcr-Abl(T315I) kinase with IC50 values of 5.0 and 9.0 nM, and inhibits the proliferation of K562 and murine Ba/F3 cells ectopically expressing Bcr-Abl(T315I) cells with IC50 values of 2 and 50 nM, respectively. It also displays good pharmacokinetics properties with an oral bioavailability of 35.3% and T(1/2) value of 48.7 h, and demonstrates significantly suppression on tumor growth in xenografted mice of K562 and Ba/F3 cells expressing Bcr-Abl(T315I). These inhibitors may serve as lead compounds for further developing new anticancer drugs overcoming the clinically acquired resistance against current Bcr-Abl inhibitors.


Assuntos
Proteínas de Fusão bcr-abl/antagonistas & inibidores , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Pirimidinas/química , Proliferação de Células , Modelos Moleculares , Mutação
9.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 35(12): 1463-8, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-26882609

RESUMO

OBJECTIVE: To observe the effects of acupuncture on neurofunction and neuropsychological factors of chronic alcoholic peripheral neuropathy (CAPN) patients. METHODS: Totally 120 CAPN patients were assigned to the common treatment group, acupuncture group A, and acupuncture group B according to random digit table, 40 in each group. All patients recieved conventional drug therapy. Besides, patients in the acupuncture group A were additionally needled at Pishu (BL20), Weishu (BL21), Xuehai (SP10), Yinlingquan (SP9), Zusanli (ST36), Yanglingquan (GB34), Jiexi (ST41), Xuanzhong (GB39), Xiangu (ST43),Taixi (KI3), Quchi (LI11), Waiguan (SJ5), Hegu (LI4), and so on. On these bases patients in the acupuncture group B were needled at Sishencong (EX-HN1), Yintang (EX-HN3), Neiguan (PC6), Taichong (LR3), Sanyinjiao (SP6), and Taiyang (EX-HN5). Acupuncture was performed once a day, 14 times as a course; and then once on every other day, 14 times in total for 4 weeks. All treatment lasted for 8 successive weeks. Neuropathy Impairment Score in the Lower Limbs (NIS-LL), Neurological Severity Score (NSS), Hamilton Depression Scale (HAMD), and Hamilton Anxiety Scale (HAMA) were assessed, motor nerve conduction velocity (MCV) and sensory nerve conduction velocity (SCV) were detected before and after treatment. RESULTS: After 8 weeks of treatment the scores of NIS-LL and NSS significantly decreased in the 3 groups, with statistical difference as compared with before treatment (P < 0.05). Scores of NIS-LL and NSS decreased more in acupuncture groups A and B than in the common treatment group (P < 0.05), and more obvious in acupuncture group B (P < 0.05). Compared with the same group before treatment, MCV and SCV of median nerve, ulnar nerve, common peroneal nerve and tibial nerve increased in acupuncture treatment group A and B after 8-week treatment (P < 0.05). MCV of median nerve, MCV and SCV of common peroneal nerve and tibial nerve significantly increased in the common treatment group (P < 0.05). Compared with the common treatment group, SCV of median nerve, MCV and SCV of ulnar nerve, common peroneal nerve and tibial nerve obviously increased in acupuncture treatment groups A and B after treatment (P < 0.05). MCV of ulnar nerve, MCV and SCV of common peroneal nerve and tibial nerve obviously increased more in acupuncture treatment group A than in acupuncture treatment group B (P < 0.05). At week 8 after treatment scores of HAMD and HAMA were obviously lowered in acupuncture groups A and B, with statistical difference as compared with before treatment (P < 0.05). The scores of HAMD were also decreased in the common treatment group, as compared with before treatment (P < 0.05). At week 8 after treatment scores of HAMD and HAMA were obviously lowered more in acupuncture treatment group B than in acupuncture treatment group A (P < 0.05). CONCLUSION: Acupuncture therapy could effectively improve the neurofunction of CAPN patients, and improve complicated anxiety and depression by additionally needling at Sishencong (EX-HN1), Yintang (EX-HN3), Taichong (LR3), Sanyinjiao (SP6), and Taiyang (EX-HN5).


Assuntos
Terapia por Acupuntura , Transtornos Relacionados ao Uso de Álcool/terapia , Doenças do Sistema Nervoso Periférico/terapia , Pontos de Acupuntura , Ansiedade , Depressão , Transtorno Depressivo , Medicamentos de Ervas Chinesas , Humanos
10.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 39(11): 1105-10, 2014 Nov.
Artigo em Zh | MEDLINE | ID: mdl-25432365

RESUMO

OBJECTIVE: To investigate the eff ect of intestinal trefoil factor (ITF) on the transcriptional activity of ITF promoter and to explore the regulatory mechanism of Janus kinase/signal transducers and activators of transcription (JAK/STAT) on ITF promoter. METHODS: The 5' flanking sequence of the ITF gene was cloned from human whole blood genomic DNA by PCR. ITF promoter fragment was cloned and inserted into the pGL3-Basic vector to construct recombinant vector. ITF promoter vector was stimulated with ITF at various concentrations and the luciferase activity was measured. The JAK-STAT3 signal transduction pathway was then blocked by a specific inhibitor AG490 to determine the signal pathway involved in ITF promoter activity. RESULTS: Restriction endonuclease analysis and DNA sequencing confirmed that the recombinant plasmid, containing ITF promoter, was constructed successfully. After transient transfection, the activity of ITF promoter was increased significantly in the presence of ITF (P<0.05). Blockage of the JAK-STAT3 signal transduction pathway with AG490 significantly reduced the ITF promoter activity (P<0.05). CONCLUSION: ITF increases the transcriptional activity of ITF promoter via the JAK-STAT3 signal transduction pathway.


Assuntos
Janus Quinases/metabolismo , Peptídeos/metabolismo , Regiões Promotoras Genéticas , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Humanos , Transfecção , Fator Trefoil-2 , Tirfostinas
11.
Sci Total Environ ; 946: 174326, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38950631

RESUMO

A significant reduction in carbon dioxide (CO2) emissions caused by transportation is essential for attaining sustainable urban development. Carbon concentrations from road traffic in urban areas exhibit complex spatial patterns due to the impact of street configurations, mobile sources, and human activities. However, a comprehensive understanding of these patterns, which involve complex interactions, is still lacking due to the human perspective of road interface characteristics has not been taken into account. In this study, a mobile travel platform was constructed to collect both on-road navigation Street View Panoramas (OSVPs) and the corresponding CO2 concentrations. >100 thousand sample pairs that matched "street view-CO2 concentration" were obtained, covering 675.8 km of roads in Shenzhen, China. In addition, four ensemble learning (EL) models were utilized to establish nonlinear connections between the semantic and object features of streetscapes and CO2 concentrations. After performing EL fusion modeling, the predictive R2 in the test set exceeded 90 %, and the mean absolute error (MAE) was <3.2 ppm. The model was applied to Baidu Street View Panoramas (BSVPs) in Shenzhen to generate a map of average on-road CO2 with a 100 m resolution, and the Local Indicator of Spatial Association (LISA) was then used to identify high CO2 intensity spatial clusters. Additionally, the Light Gradient Boost-SHapley Additive exPlanation (LGB-SHAP) analysis revealed that vertically planted trees can reduce CO2 emissions from on-road sources. Moreover, the factors that affect on-road CO2 exhibit interaction and threshold effects. Street View Panoramas (SVPs) and Artificial Intelligence (AI) were adopted here to enhance the spatial measurement of on-road CO2 concentrations and the understanding of driving factors. Our approach facilitates the assessment and design of low-emission transportation in urban areas, which is critical for promoting sustainable traffic development.

12.
Pharmazie ; 68(5): 365-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23802435

RESUMO

Allopurinol is a popular and widely-prescribed anti-hyperuricemic agent that has been implicated in drug interactions with substrates of several cytochrome P450 (CYP) enzymes. The effect of repeated allopurinol administration (20 mg/kg, once daily for 14 days) on metabolic activity of CYP was assessed in rats. This was a randomized, double-blind, two-way crossover study with a 4-week washout period between phases. The substrates used in this study were phenacetin (CYP1A2), tolbutamide (CYP2C9), omeprazole (CYP2C19) and dextromethorphan (CYP2D6). Validated HPLC-MS/MS was used to quantify all compounds. Our study showed that allopurinol administration inhibited CYP1A2 activity, causing a significant increase in AUC (0-infinity) (P < 0.01) and t1/2 (P < 0.05) of phenacetin, and a distinct decline in CL (P < 0.01). However, there were no significant differences of another three probe drugs in plasma concentrations and the corresponding pharmacokinetic parameters between the allopurinol-treated and normal saline-treated rats. The findings in this study suggested that allopurinol could inhibit CYP1A2 but did not influence CYP2C9, CYP2C19 and CYP2D6 enzymes.


Assuntos
Alopurinol/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Inibidores Enzimáticos/farmacologia , Animais , Área Sob a Curva , Meia-Vida , Indicadores e Reagentes , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Masculino , Oxirredução , Preparações Farmacêuticas/metabolismo , Farmacocinética , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
13.
Discov Oncol ; 14(1): 40, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37012515

RESUMO

INTRODUCTION: Triple-negative breast cancer (TNBC) is currently the most malignant subtype of breast cancer without effective targeted therapies. DNAJB4 (Dnaj heat shock protein family (Hsp40) member B4) is a member of the human heat shock protein family (Hsp40). The clinical significance of DNAJB4 in breast cancer has been reported in our previous study. However, the biological function of DNAJB4 in TNBC cell apoptosis remains unclear to date. METHODS: The expression of DNAJB4 in normal breast cells, breast cancer cells, four-paired TNBC tissues, and adjacent noncancerous tissues was quantified by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assay. The role of DNAJB4 in TNBC cell apoptosis was investigated using a number of gain- and loss-of-function in vitro and in vivo assays. The underlying molecular mechanisms in TNBC cell apoptosis were elucidated via Western blot assay. RESULTS: DNAJB4 expression was significantly downregulated in TNBC tissues and cell lines. DNAJB4 knockdown inhibited TNBC cell apoptosis and promoted tumorigenicity in vitro and in vivo, but DNAJB4 overexpression resulted in the opposite. Mechanically, DNAJB4 knockdown inhibited TNBC cell apoptosis through suppression of the Hippo signaling pathway, and the result was reversed after DNAJB4 overexpression. CONCLUSIONS: DNAJB4 promotes TNBC cell apoptosis by activating the Hippo signaling pathway. Therefore, DNAJB4 may act as a prognostic biomarker and therapeutic target for TNBC.

14.
Natl Sci Rev ; 10(2): nwac195, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36817831

RESUMO

Although short bamboo nodes function in mechanical support and fluid exchange for bamboo survival, their structures are not fully understood compared to unidirectional fibrous internodes. Here, we identify the spatial heterostructure of the bamboo node via multiscale imaging strategies and investigate its mechanical properties by multimodal mechanical tests. We find three kinds of hierarchical fiber reinforcement schemes that originate from the bamboo node, including spatially tightened interlocking, triaxial interconnected scaffolding and isotropic intertwining. These reinforcement schemes, built on porous vascular bundles, microfibers and more-refined twist-aligned nanofibers, govern the structural stability of the bamboo via hierarchical toughening. In addition, the spatial liquid transport associated with these multiscale fibers within the bamboo node is experimentally verified, which gives perceptible evidence for life-indispensable multidirectional fluid exchange. The functional integration of mechanical reinforcement and liquid transport reflects the fact that the bamboo node has opted for elaborate structural optimization rather than ingredient richness. This study will advance our understanding of biological materials and provide insight into the design of fiber-reinforced structures and biomass utilization.

15.
Front Oncol ; 13: 1152013, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37361565

RESUMO

Background: AI-based clinical decision support system (CDSS) has important prospects in overcoming the current informational challenges that cancer diseases faced, promoting the homogeneous development of standardized treatment among different geographical regions, and reforming the medical model. However, there are still a lack of relevant indicators to comprehensively assess its decision-making quality and clinical impact, which greatly limits the development of its clinical research and clinical application. This study aims to develop and application an assessment system that can comprehensively assess the decision-making quality and clinical impacts of physicians and CDSS. Methods: Enrolled adjuvant treatment decision stage early breast cancer cases were randomly assigned to different decision-making physician panels (each panel consisted of three different seniority physicians in different grades hospitals), each physician made an independent "Initial Decision" and then reviewed the CDSS report online and made a "Final Decision". In addition, the CDSS and guideline expert groups independently review all cases and generate "CDSS Recommendations" and "Guideline Recommendations" respectively. Based on the design framework, a multi-level multi-indicator system including "Decision Concordance", "Calibrated Concordance", " Decision Concordance with High-level Physician", "Consensus Rate", "Decision Stability", "Guideline Conformity", and "Calibrated Conformity" were constructed. Results: 531 cases containing 2124 decision points were enrolled; 27 different seniority physicians from 10 different grades hospitals have generated 6372 decision opinions before and after referring to the "CDSS Recommendations" report respectively. Overall, the calibrated decision concordance was significantly higher for CDSS and provincial-senior physicians (80.9%) than other physicians. At the same time, CDSS has a higher " decision concordance with high-level physician" (76.3%-91.5%) than all physicians. The CDSS had significantly higher guideline conformity than all decision-making physicians and less internal variation, with an overall guideline conformity variance of 17.5% (97.5% vs. 80.0%), a standard deviation variance of 6.6% (1.3% vs. 7.9%), and a mean difference variance of 7.8% (1.5% vs. 9.3%). In addition, provincial-middle seniority physicians had the highest decision stability (54.5%). The overall consensus rate among physicians was 64.2%. Conclusions: There are significant internal variation in the standardization treatment level of different seniority physicians in different geographical regions in the adjuvant treatment of early breast cancer. CDSS has a higher standardization treatment level than all physicians and has the potential to provide immediate decision support to physicians and have a positive impact on standardizing physicians' treatment behaviors.

16.
Environ Monit Assess ; 184(3): 1299-310, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21625920

RESUMO

Chagan Lake is located downstream of the Second Songhua River basin in Northeast China. It is one of the top ten inland freshwater lakes, and an important aquatic farm in China. The lake has been receiving large amounts (currently at 1.5 × 10(8) m(3)/a) of water from the river since 1984. This would pose a threat to the aquatic system of the lake because the river was seriously polluted with mercury in 1970s-1980s. The current study is the first to report the total mercury concentrations in fish found in the lake. Mercury concentrations in seven fish species collected from the lake in January 2009 were determined. The related human health risk from fish consumption was also assessed. The average concentration of mercury in the fish was 18.8 µg/kg of wet weight, ranging from 4.5 to 37.6 µg/kg of wet weight. A large difference in the mercury concentrations among the fish species was found. The mercury concentration was found to be higher in carnivorous species and lower in omnivorous and herbivorous species. This demonstrates greater mercury bioaccumulation in fish species at higher trophic levels. Mercury concentrations in fish showed significant positive correlations with age, length, and weight. No significant relationship was found between mercury concentrations in fish and the habitat preferences. Mercury concentrations in fish from the lake were within the limits of the international and national standards of China established for mercury. According to the reference doses established by the United States Environmental Protection Agency, the maximum safe consuming quantity considering all the fish was 297.3 g/day/person, which was more than five times as much as the current quantity (50 g/day/person) consumed by the local residents. This investigation indicates that the historical pollution of the Second Songhua River has not caused mercury bioaccumulation in fish muscle tissue of Chagan Lake. The present consumption of fish from the lake in the local area does not pose a threat to human health.


Assuntos
Peixes/metabolismo , Mercúrio/metabolismo , Músculos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , China , Monitoramento Ambiental , Lagos/química , Mercúrio/análise , Poluentes Químicos da Água/análise
17.
Materials (Basel) ; 15(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36295218

RESUMO

Concrete presents different internal micro-structure and damage characteristics because of the different content of steel fibers and the randomness of its distribution. Therefore, the failure process of steel-fiber-reinforced concrete (SFRC) should be divided into different stages and the damage types should be classified to further clarify the strengthening mechanism of steel fibers. The role of volume fractions of steel fibers in the splitting-tensile strength of concrete was investigated by split tensile tests for concrete with four different volume fractions of steel fibers (0.0%, 1.0%, 1.5%, 2.0%). The acoustic emission energy and horizontal displacement of concrete in the splitting-tensile process were monitored by combing digital image correlation (DIC) and acoustic emission (AE) techniques, and the microscopic failure mechanism of SFRC was analyzed emphatically. The results showed that the addition of steel fibers improved the splitting-tensile strength of concrete. With the increase of the volume fraction of steel fibers, the splitting-tensile strength of concrete increased first and then decreased, and reached the maximum value of 5.294 MPa when the content was 1.5%. It was observed that the overall failure mechanism could be divided into four stages: slow accumulation of elastic energy (I); rapid accumulation of elastic energy (II); rapid accumulation of dissipated energy (III); a slow decrease of elastic energy and a slow increase of dissipated energy (IV). Tensile failure dominated the failure process of concrete splitting-tensile resistance, while there was a part of shear failure.

18.
Adv Mater ; 34(2): e2105299, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34802169

RESUMO

Owing to their outstanding comprehensive performance, polyimide (PI) composite films are widely used on the external surfaces of spacecraft to protect them from the adverse conditions of low Earth orbit (LEO). However, current PI composite films have inadequate mechanical properties and atomic oxygen (AO) resistance. Herein, this work fabricates a new PI-based nanocomposite film with greatly enhanced mechanical properties and AO resistance by integrating mica nanosheets with PI into a unique double-layer nacre-inspired structure with a much higher density of mica nanosheets in the top layer. In addition, the unique microstructure and the intrinsic properties of mica also impart the nanocomposite film with favorable ultraviolet and high-temperature resistance. The comprehensive performance of this material is superior to those of pure PI, single-layer PI-mica, and previously reported PI-based composite films. Thus, the double-layer nanocomposite film displays great potential as an aerospace material for use in LEO.

19.
Adv Mater ; 34(43): e2206855, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36082538

RESUMO

Compared with raw rectorite microplatelets (RMs), rectorite nanosheets (RNs) have considerably greater application prospects in the preparation of advanced composite materials because of their larger aspect ratio, higher surface reactivity, and intrinsically superior mechanical and physical properties. However, the difficulty in the efficient preparation of RNs significantly limits their large-scale applications. Here, a scalable poly(vinylpyrrolidone)-assisted stirring approach is developed to prepare ultrathin RNs from the abundant natural RMs. A higher production rate (≈0.675 g h-1 ) is achieved compared with that of most other nanosheets. Additionally, instead of using conventional time- and energy-consuming high-speed centrifugation, an efficient poly(dienedimethylammonium chloride)-assisted sedimentation strategy is proposed here to rapidly separate the exfoliated RNs from the RN dispersion. Then, the RNs are co-assembled with aramid nanofibers (ANFs) into large-scale nacre-mimetic ANF-RN nanopapers with considerably enhanced mechanical, electrical insulating, and high-temperature-resistant properties compared with pure ANF nanopapers and ANF-RM micropapers. Moreover, these properties are superior to those of previously reported ANF-based nanopapers and commercial insulating micropapers.

20.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 31(11): 1479-82, 2011 Nov.
Artigo em Zh | MEDLINE | ID: mdl-22303708

RESUMO

OBJECTIVE: To observe the effects of combination of Lumbrukinase Capsule (LC) and Probucol Tablet (PT) in treating cerebral infarction (CI) patients' unstable atheromatous plaque of the carotid artery. METHODS: 150 patients were randomly assigned to the PT group and the LC group, 75 cases in each. Patients in the PT group took 0.5 g PT each time, twice daily. On the basis of PT, patients in the LC group also took 600 thousand U LC, thrice daily. The treatment course was 12 months for all. The serum levels of TC, TG, HDL-C, LDL-C, fibrinogen (FIB), and changes of the carotid atherosclerotic plaque were measured before treatment, 6 and 12 months after treatment. Meanwhile, adverse events were recorded. RESULTS: The serum levels of TC, TG, and LDL-C were all lower 6 months after treatment than before treatment in the two groups, showing statistical significance (P < 0.05). The serum level of HDL-C was higher 6 months after treatment than before treatment in the two groups, showing no statistical significance (P > 0.05). When compared with before treatment in the same group, the serum level of FIB significantly decreased after treatment. Besides, there was statistical difference between the two groups (P < 0.05). There was no statistical difference in the serum levels of blood lipids or FIB between 12-month treatment and 6-month treatment in the same group (P > 0.05). The plaque effective rate in the LC group was superior to that of the PT group, showing statistical significance (P < 0.01). During the treatment period, the occurrence of cerebrovascular event was lower in the LC group than in the PT group (P < 0.05). Partial patients in the two groups had gastric discomfort. CONCLUSIONS: The combination of LC and PT could prevent and treat arteriosclerosis, stabilize the plaque, effectively lower the occurrence of ischemic events. Its clinical application did not increase the risk of hemorrhage. It was safe and effective, worthy of spreading. It was necessary to further observe whether combination of LC and PT could increase side effects of the digestive tract.


Assuntos
Infarto Cerebral/tratamento farmacológico , Materia Medica/uso terapêutico , Placa Aterosclerótica/tratamento farmacológico , Probucol/uso terapêutico , Serina Endopeptidases/uso terapêutico , Adulto , Idoso , Animais , Produtos Biológicos/uso terapêutico , Doenças das Artérias Carótidas/tratamento farmacológico , Infarto Cerebral/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oligoquetos/enzimologia , Resultado do Tratamento
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