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1.
BMC Med Educ ; 23(1): 840, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37936146

RESUMO

BACKGROUND: The effectiveness of team-interaction training has been proven. However, there is a lack of objective and accurate evaluation tools for the impact and benefits of team-interaction training on participants. This study aims to develop and validate a tool for exploring undergraduates' perception of benefits in team-interaction. It can further insight into the perceived benefits of team-interaction training for undergraduates and evaluates the effectiveness of the course, and provides a reference point for the development of university team-interaction training courses. METHODS: This study was conducted in three stages. Phase 1 consisted of item generation: A theoretical framework was crafted based on social cognitive theory, self-efficacy theory, and sports performance models. Fifty-two items were generated based on the theoretical framework, participant interviews, and literature review. After Delphi consultation and pilot tests, 39 items moved on to Phase 2. Phase 2 consisted of forming a preliminary questionnaire: the contents to be included were selected through item analysis and exploratory factor analysis (EFA). A total of 40 classes were selected for EFA. After EFA, a three-factor structure with 25 items was formed. The third stage tested psychometric properties through confirmatory factor analysis (CFA), test-retest reliability, criterion-related validity, and internal consistency. RESULTS: The final PBTITQ consisted of 23 items, each rated from "1" (fully disagree) to "5" (fully agree). EFA and CFA supported the three-factor structure of PBTITQ, which included Cohesion, Communication, and Efficiency. The Cronbach's alpha of the PBTITQ was 0.90, the test-retest reliability was 0.88, and the split-half reliability was 0.81. PBTITQ significantly correlated with the GEQ (r = 0.808, p < 0.05) and the TDM (r = 0.796, p < 0.05). CONCLUSION: The PBTITQ is an effective tool for assessing the perceived benefits of team-interaction training among undergraduates.


Assuntos
Estudantes , Humanos , Reprodutibilidade dos Testes , Estudantes/psicologia , Inquéritos e Questionários , Psicometria , Análise Fatorial
2.
Zhongguo Zhong Yao Za Zhi ; 48(14): 3701-3714, 2023 Jul.
Artigo em Zh | MEDLINE | ID: mdl-37475061

RESUMO

This study aimed to explore the anti-inflammatory material basis and molecular mechanism of Artemisia stolonifera based on the analysis of the chemical components in different extracted fractions of A. stolonifera and their antioxidant and anti-inflammatory effects in combination with network pharmacology and molecular docking. Thirty-two chemical components were identified from A. stolonifera by ultra-performance liquid chromatography coupled to tandem quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS). Among them, there were 7, 21 and 22 compounds in water, n-butanol and ethyl acetate fractions, respectively. The antio-xidant capacity of different extracted fractions was evaluated by measuring their scavenging ability against 1,1-diphenyl-2-picrylhydrazyl radical 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl(DPPH) and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonic acid)(ABTS) free radicals and total antioxidant capacity [ferric reducing antioxidant power(FRAP) assay]. The inflammatory model of RAW264.7 cells was induced by lipopolysaccharide(LPS), and the levels of nitrite oxide(NO), tumor necrosis factor-α(TNF-α), interleukin-6(IL-6) in the supernatant and the mRNA expression of related inflammatory factors in cells were used to evaluate the anti-inflammatory effects. The results revealed that ethyl acetate fraction of A. stolonifera was the optimal antioxidant and anti-inflammatory fraction. By network pharmacology, it was found that flavonoids such as rhamnazin, eupatilin, jaceosidin, luteolin and nepetin could act on key targets such as TNF, serine/threonine protein kinase 1(AKT1), tumor protein p53(TP53), caspase-3(CASP3) and epidermal growth factor receptor(EGFR), and regulate the phosphatidylinositol-3-kinase-protein kinase B(PI3K-AKT) and mitogen-activated protein kinase(MAPK) signaling pathways to exert the anti-inflammatory effects. Molecular docking further indicated excellent binding properties between the above core components and core targets. This study preliminarily clarified the anti-inflammatory material basis and mechanism of ethyl acetate fraction of A. stolonifera, providing a basis for the follow-up clinical application of A. stolonifera and drug development.


Assuntos
Artemisia , Medicamentos de Ervas Chinesas , Antioxidantes/farmacologia , Antioxidantes/química , Simulação de Acoplamento Molecular , Farmacologia em Rede , Fosfatidilinositol 3-Quinases , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Medicamentos de Ervas Chinesas/farmacologia , Interleucina-6
3.
Plant Dis ; 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36548919

RESUMO

Cynanchum stauntonii is a perennial herb plant of the Asclepiadaceae family. The dried roots and rhizomes have been used as medicine in China for 1500 years and are considered a remedy for cough and phlegm. In recent years, the wild C. stauntonii resources have not been sufficient for market demand, therefore, a large artificial cultivation area was established in Xinzhou, Tuanfeng and Macheng in Hubei province. In March and April 2022, serious outbreaks of seedling blight were observed in C. stauntonii in Xinzhou county (N30°48'12″, E114°49'24″), and the disease occurred on 10 to 15% of plants in five C. stauntonii nursery beds. Early symptoms included withered tips, chlorosis, stunting, yellow leaves and leaf drop, and later, seedlings die in patches. To determine the causal agent of disease, pieces (5 mm × 5 mm) of diseased tissue at the junction of disease and healthy tissue were surface disinfected by soaking in 75% ethanol for 3 min, rinsed three times with sterilized water, and pieces were placed on PDA at 25°C. Fungal isolates obtained were yellow-brown at the center and pink to white toward the periphery, and dark red pigments were observed in the agar. Isolates were cultured in synthetic low nutrient agar (SNA) and carnation leaf agar to observe the spore morphology. The macroconidia were sickle-shaped with 3-4 septate, with sizes of 30.26±2.36×3.77±0.53 µm on SNA and 33.52±2.20×3.81±0.48 µm on carnation leaf agar (n=30). Morphological characteristics of the isolates were consistent with those of Fusarium sp in the Fusarium Laboratory Manual (Leslie et al. 2006). Furthermore, the genomic DNA from a representative isolate BQ-2 was extracted, the ITS, TEF-1α, RPB1 and RPB2 genes were amplified with primers ITS1/ITS4, EF1/EF2, Fa/G2R and 5F2/7cr, respectively (Zhang et al. 2022). BLAST analysis showed that the ITS (ON935780.1), TEF-1α (OP985126.1), RPB1 (OP985125.1) and RPB2 (OP985124.1) amplicon sequence were 99.44%, 98.94%, 99.88% and 100% identical to the sequences of F. tricinctum strain (KU350724.1, AB674264.1, LC701712.1, MW474678.1), respectively. A phylogenetic tree constructed based on a concatenated sequence (ITS, TEF-1α, RPB1, RPB2) using the neighbor-joining and maximum likelihood method in MEGA7 revealed that BQ-2 grouped with concatenated sequences from four representative F. tricinctum isolates in GenBank. Based on the morphological characteristics and molecular identification, the strain BQ-2 was identified as F. tricinctum. For pathogenicity tests, 5 mm pieces of a BQ-2 colony on PDA were placed on excised leaves of healthy C. stauntonii wounded with a needle (n=5) and kept at 25±2℃. Leaves treated PDA were used as a control (Li et al.2020). After three days inoculation, the mycelia proliferated and began to infect leaf tissues. Ten days later, large parts of the detached leaves were extensively infested with the pathogen and brown. For live plant inoculation, stem bases of five healthy seedlings were punctured with sterile needle and then inoculated with BQ-2 mycelia from PDA. Controls were treated with only PDA. The seedlings began wilting after three days and at five days showed typical disease symptoms, similar to those observed in the field. The controls were asymptomatic. The pathogen was reisolated from the diseased tissues, and the colonies and microscopic characteristics were similar to those of BQ-2. To the best of our knowledge, this is the first report of F. tricinctum causing seedling blight on C. stauntonii in China. This report will provide resources and reference for controlling the increased incidence and economic losses of seedling blight on C. stauntonii.

4.
J Ethnopharmacol ; 331: 118344, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38754641

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Dermatophytes are notorious pathogens capable of infecting various mammals skin, posing serious threats to human health and overall life quality worldwide. Artemisia argyi has been recorded and applied for over a thousand years to treat skin itching. Although it has the potential to be developed as a plant-based antifungal agent, it's antifungal activity and action mechanism of active ingredients are still unclear. AIM OF THE STUDY: The aim of this study was to investigate the chemical composition, antifungal activity against skin fungi, and potential mechanisms of Artemisia argyi essential oil (AEO). MATERIALS AND METHODS: The chemical composition of AEO was analyzed by gas chromatography-mass spectrometry (GC-MS) firstly. Flat growth restraint and double half dilution tests was performed to evaluate AEO antifungal activity against Microsporum gypseum, Trichophyton mentagrophytes, and Trichophyton rubrum. And then, the physiological mechanism of AEO inhibiting dermatophytes was systematically explored through scanning electron microscopy, relative conductivity, membrane leakage, ROS content, and antioxidant enzyme activity. Finally, the main pathways were screened through transcriptome sequencing, while the related genes expression levels and enzyme activity were validated. RESULTS: Monoterpenes and sesquiterpenoids were the most highly representative class of AEO. AEO had powerful antifungal activity against M. gypseum, T. mentagrophytes, and T. rubrum, with minimum inhibitory concentration (MIC) values of 0.6, 1.2, and 1.2 µL/mL, respectively. Moreover, AEO can also damage the cell membrane integrity of T. mentagrophytes, resulting in cellular extravasation of intracellular substances. Transcriptome analysis revealed that the main target of AEO is to inhibit electron transfer and oxidative phosphorylation during respiration, ultimately leading to obstruction of normal ATP synthesis and energy metabolism in mitochondria. And a large amount of ROS will generate due to the incompletely catalysis of oxygen under mitochondrial complexes. Coupled with the decrease of antioxidant enzyme (SOD, POD) activity, excessive accumulation of ROS will cause serious oxidative damage to cells and eventually exhibiting antifungal activity against dermatophytes. CONCLUSIONS: The present study demonstrated that Artemisia argyi was a valuable source of active compounds with antifungal activity. These findings support AEO as a potential agent to inhibit dermatophytes and prevent related dermatophytoses.


Assuntos
Antifúngicos , Artemisia , Arthrodermataceae , Óleos Voláteis , Fosforilação Oxidativa , Estresse Oxidativo , Artemisia/química , Antifúngicos/farmacologia , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Arthrodermataceae/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fosforilação Oxidativa/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Cromatografia Gasosa-Espectrometria de Massas
5.
Front Pharmacol ; 15: 1371811, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38957384

RESUMO

Objective: The study was designed to develop and validate a new drug clinical trial participation feelings questionnaire (DCTPFQ) for cancer patients. Methods: Data collection and analysis involved a combination of qualitative and quantitative methods. There were two phases to this study. Phase Ⅰ involved developing a questionnaire to establish a list of items to be included in the pool: A theoretical framework was constructed based on the transitions theory and the Roper-Logan-Tierney theory. After incorporating a theoretical framework, interviewing participants, and reviewing the literature, 44 items were generated. After a Delphi consultation and a pilot test, 36 items proceeded to item analysis and exploratory factor analysis (EFA), and a four-factor structure with 21 items was formed. Confirmatory factor analysis (CFA), test-retest reliability, criteria-related validity, and internal consistency tests were conducted in phase II to examine the psychometric properties. Results: There were 21 items on the DCTPFQ, ranging from 1 (fully disagree) through 5 (fully agree). As a result of EFA and CFA, the four factors of DCTPFQ could be verified, including cognitive engagement, subjective experience, medical resources, and relatives and friends' support. Test-retest reliability of the DCTPFQ was 0.840, and Cronbach's alpha was 0.934. DCTPFQ is significantly correlated with the Fear of Progression Questionnaire-short form (r = 0.731, p < 0.05) and the Mishel's Uncertainty in Illness Scale (r = 0.714, p < 0.05). Conclusion: The DCTPFQ is a useful tool for measuring the drug clinical trial participation feelings among cancer patients.

6.
Chin J Nat Med ; 22(1): 47-61, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38278559

RESUMO

Artemisia argyi (A. argyi), a plant with a longstanding history as a raw material for traditional medicine and functional diets in Asia, has been used traditionally to bathe and soak feet for its disinfectant and itch-relieving properties. Despite its widespread use, scientific evidence validating the antifungal efficacy of A. argyi water extract (AAWE) against dermatophytes, particularly Trichophyton rubrum, Trichophyton mentagrophytes, and Microsporum gypseum, remains limited. This study aimed to substantiate the scientific basis of the folkloric use of A. argyi by evaluating the antifungal effects and the underlying molecular mechanisms of its active subfraction against dermatophytes. The results indicated that AAWE exhibited excellent antifungal effects against the three aforementioned dermatophyte species. The subfraction AAWE6, isolated using D101 macroporous resin, emerged as the most potent subfraction. The minimum inhibitory concentrations (MICs) of AAWE6 against T. rubrum, M. gypseum, and T. mentagrophytes were 312.5, 312.5, and 625 µg·mL-1, respectively. Transmission electron microscopy (TEM) results and assays of enzymes linked to cell wall integrity and cell membrane function indicated that AAWE6 could penetrate the external protective barrier of T. rubrum, creating breaches ("small holes"), and disrupt the internal mitochondrial structure ("granary"). Furthermore, transcriptome data, quantitative real-time PCR (RT-qPCR), and biochemical assays corroborated the severe disruption of mitochondrial function, evidenced by inhibited tricarboxylic acid (TCA) cycle and energy metabolism. Additionally, chemical characterization and molecular docking analyses identified flavonoids, primarily eupatilin (131.16 ± 4.52 mg·g-1) and jaceosidin (4.17 ± 0.18 mg·g-1), as the active components of AAWE6. In conclusion, the subfraction AAWE6 from A. argyi exerts antifungal effects against dermatophytes by disrupting mitochondrial morphology and function. This research validates the traditional use of A. argyi and provides scientific support for its anti-dermatophytic applications, as recognized in the Chinese patent (No. ZL202111161301.9).


Assuntos
Artemisia , Arthrodermataceae , Antifúngicos/farmacologia , Antifúngicos/química , Artemisia/química , Simulação de Acoplamento Molecular , Mitocôndrias , Testes de Sensibilidade Microbiana
7.
J Affect Disord ; 350: 838-846, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38278327

RESUMO

BACKGROUND: The associations of plant-based dietary patterns with depression and anxiety symptoms among older adults have not been extensively studied. Therefore, the purpose of this study was to examine these associations in Chinese older adults. METHODS: Data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) was employed in the present study. The simplified food frequency questionnaire was used to assess the overall plant-based diet index (PDI), healthful plant-based diet index (hPDI), and unhealthful plant-based diet index (uPDI). The Center for Epidemiologic Studies Depression Scale-10 (CES-D-10) was used to evaluate depression symptoms, and the Generalized Anxiety Disorder Scale-7 (GAD-7) was used to assess anxiety symptoms. This study employed logistic regression and linear regression to examine the associations between plant-based dietary patterns and symptoms of depression and anxiety. RESULTS: This study included 11,971 older adults, with a mean age of 83.23 ± 11.10 years. The results indicated that PDI and hPDI were negative associated with depression symptoms (adjusted ß -0.09, 95 % CI -0.11, -0.07) (adjusted ß -0.09, 95 % CI -0.11, -0.07) and anxiety symptoms (adjusted ß -0.03, 95 % CI -0.04, -0.02) (adjusted ß -0.04, 95 % CI -0.05, -0.02), while uPDI was positive associated with depression symptoms (adjusted ß 0.09, 95 % CI 0.07, 0.11) and anxiety symptoms (adjusted ß 0.04, 95 % CI 0.03, 0.05). CONCLUSIONS: The findings from this study have the potential to promote healthy dietary patterns in older adults, and may have implications for the prevention and management of depression and anxiety in this population.


Assuntos
Depressão , Padrões Dietéticos , Humanos , Idoso , Idoso de 80 Anos ou mais , Depressão/epidemiologia , Ansiedade/epidemiologia , Transtornos de Ansiedade/epidemiologia , China/epidemiologia , Dieta
8.
Int J Biol Macromol ; 266(Pt 1): 131169, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554899

RESUMO

Autogenous bone transplantation is a prevalent clinical method for addressing bone defects. However, the limited availability of donor bone and the morbidity associated with bone harvesting have propelled the search for suitable bone substitutes. Bio-inspired scaffolds, particularly those fabricated using electron beam melting (EBM) deposition technology, have emerged as a significant advancement in this field. These 3D-printed titanium alloy scaffolds are celebrated for their outstanding biocompatibility and favorable elastic modulus. Thermosensitive chitosan hydrogel, which transitions from liquid to solid at body temperature, serves as a popular carrier in bone tissue engineering. Icariin (ICA), known for its efficacy in promoting osteoblast differentiation from bone marrow mesenchymal stem cells (BMSCs), plays a crucial role in this context. We developed a system combining a 3D-printed titanium alloy with a thermosensitive chitosan hydrogel, capable of local bone regeneration and integration through ICA delivery. Our in vitro findings reveal that this system can gradually release ICA, demonstrating excellent biocompatibility while fostering BMSC proliferation and osteogenic differentiation. Immunohistochemistry and Micro-CT analyses further confirm the effectiveness of the system in accelerating in vivo bone regeneration and enhancing osseointegration. This composite system lays a significant theoretical foundation for advancing local bone regeneration and integration.


Assuntos
Ligas , Diferenciação Celular , Quitosana , Flavonoides , Hidrogéis , Células-Tronco Mesenquimais , Osseointegração , Osteogênese , Impressão Tridimensional , Alicerces Teciduais , Titânio , Quitosana/química , Quitosana/farmacologia , Titânio/química , Osseointegração/efeitos dos fármacos , Ligas/química , Ligas/farmacologia , Alicerces Teciduais/química , Animais , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , Hidrogéis/química , Hidrogéis/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Engenharia Tecidual/métodos
9.
Sci Rep ; 13(1): 11247, 2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37438416

RESUMO

Health-related quality of life, sleep quality, morning and evening types, and internet addiction are of significant importance to the development of medical students, yet they have rarely been studied. Taking this into consideration, the study aimed to confirm latent profiles in health-related quality of life, sleep quality, morning and evening types, and internet addiction in medical students and investigate the characteristics of participants in each profile to provide suggestions for students' health. This was an observational cross-sectional study including 1221 medical student subjects at China Medical University in 2019. Multiple correspondence analysis was the initial step to verify the correspondence, dispersion, and approximation of variable categories. Latent profile analysis was used to identify the multiple correspondences between the levels of variables. Three profiles were found, including: (1) The Low sleep quality profile was characterized by the lowest sleep quality among the three existing profiles. (2) The High health-related quality of life and Low internet addiction profile was characterized by the highest level of health-related quality of life but the lowest level of internet addiction. (3) The Low health-related quality of life and High internet addiction profile was characterized by the highest standardized values of internet addiction but the lowest standardized values of health-related quality of life. This study had important implications for improving student health and supported the medical universities and hospitals in implementing targeted policies based on distinctive student characteristics.


Assuntos
Estudantes de Medicina , Humanos , Estudos Transversais , Transtorno de Adição à Internet , Qualidade de Vida , Qualidade do Sono
10.
Nutrients ; 15(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37836557

RESUMO

Unhealthy dietary behaviors and body dissatisfaction are becoming increasingly common among college students. Understanding the association between body image flexibility and intermittent fasting is particularly meaningful, especially for medical college students. This study aimed to investigate the association between body image flexibility and intermittent fasting among medical students. We conducted a cross-sectional study with 5138 medical college students at Jitang College of North China University of Science and Technology. Univariate and multivariate logistic regression were used to evaluate the association between body image flexibility and intermittent fasting. Subgroup analysis and interaction tests were further used to examine the possible interaction between body image flexibility and intermittent fasting. In this study, 1329 (25.87%) students had intermittent fasting behavior. After adjustment for confounding factors, there was a negative association between body image flexibility and intermittent fasting (OR = 0.94, 95%CI = 0.93 to 0.95, p < 0.001). A significant interaction between body image flexibility and intermittent fasting was found in gender, academic year, major, and monthly living expenses (p for interaction < 0.05). E-value analysis suggested there was unlikely to be an unmeasured confounding. This association could contribute to the establishment of personalized health intervention strategies and provide recommendations for promoting the physical and mental health of medical students.


Assuntos
Imagem Corporal , Estudantes de Medicina , Humanos , Imagem Corporal/psicologia , Estudos Transversais , Jejum Intermitente , População do Leste Asiático , China , Universidades
11.
Nanomaterials (Basel) ; 13(12)2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37368298

RESUMO

The emergent optical activity (OA) caused by anisotropic light emitter in microcavities is an important physical mechanism discovered recently, which leads to Rashba-Dresselhaus photonic spin-orbit (SO) coupling. In this study, we report a sharp contrast of the roles of the emergent OA in free and confined cavity photons, by observing the optical chirality in a planar-planar microcavity and its elimination in a concave-planar microcavity, evidenced by polarization-resolved white-light spectroscopy, which agrees well with the theoretical predictions based on the degenerate perturbation theory. Moreover, we theoretically predict that a slight phase gradient in real space can partially restore the effect of the emergent OA in confined cavity photons. The results are significant additions to the field of cavity spinoptronics and provide a novel method for manipulating photonic SO coupling in confined optical systems.

12.
Yao Xue Xue Bao ; 47(2): 158-62, 2012 Feb.
Artigo em Zh | MEDLINE | ID: mdl-22512024

RESUMO

With the excellent merits of wide analytical range, high sensitivity, small sample size, fast analysis speed, good repeatability, simple operation, low mobile phase consumption, as well as its capability of simultaneous isolation and identification, etc, mass spectrometry techniques have become widely used in the area of environmental science, energy chemical industry, biological medicine, and so on. This article reviews the application of mass spectrometry technology in biological sample analysis in the latest three years with the focus on the new applications in pharmacokinetics and bioequivalence, toxicokinetics, pharmacokinetic-pharmacodynamic, population pharmacokinetics, identification and fragmentation pathways of drugs and their metabolites and metabonomics to provide references for further study of biological sample analysis.


Assuntos
Espectrometria de Massas/métodos , Preparações Farmacêuticas , Animais , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Metabolômica , Preparações Farmacêuticas/química , Farmacocinética , Farmacologia , Equivalência Terapêutica
13.
Medicine (Baltimore) ; 101(28): e29450, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35839002

RESUMO

The optimal treatment strategy for femoral neck fractures remained controversial, especially the Pauwels type III femoral neck fracture of young patients was a challenge. Femoral neck system (FNS) was a newly developed internal fixation for treating femoral neck fracture and this study aimed to compare the biomechanical advantages and disadvantages between FNS and 3 cannulated configuration screws (CCS) with or without an additional medial buttress plate (MBP). In this study, Pauwels type III femoral neck fracture model with an angle of 70° was constructed and 3 different fixation models, FNS, CCS + MBP, CCS alone, were developed. A vertical force of 2100N was applied on the femoral head, then the maximum von Mises stress of whole model, distal femur, femoral head, and internal fixation was recorded, as well as the stress distribution of whole model, proximal fracture section, and internal fixation of the 3 models. Moreover, the maximum displacement of the whole model, distal femur, femoral head, internal fixation, and the relative displacement of the proximal and distal portion was also compared. The maximum von Mises stress value was 318.302 MPa in FNS, 485.226 MPa in CCS + 1/3 plate, and 425.889 MPa in CCS. The FNS showed lowest maximum von Mises stress values in distal part, femoral head, and internal implant. All fixation configurations were observed stress concentrated at the posteroinferior area of cross-section of femoral head and at the fracture section area of implant; however, FNS had more uniform stress distribution. For displacement, the maximum displacement value was 8.5446 mm in FNS, 8.2863 mm in CCS + 1/3 plate, and 8.3590 mm in CCS. However, FNS had higher maximum displacement in femoral head and internal implant, but lower maximum displacement in the distal part of fracture model. The FNS represented a significantly higher relative displacement between the femoral head and distal femur when compared with the other 2 fixation configurations. The newly developed FNS could achieve the dual effect of angular stability and sliding compression for the treatment of Pauwels type III femoral neck fractures, which provided superior biomechanical stability than CCS alone and CCS with additional MBP.


Assuntos
Fraturas do Colo Femoral , Fenômenos Biomecânicos , Parafusos Ósseos , Fraturas do Colo Femoral/cirurgia , Colo do Fêmur/cirurgia , Análise de Elementos Finitos , Fixação Interna de Fraturas , Humanos
14.
Adv Mater ; 34(31): e2200363, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35686916

RESUMO

Obtaining large plastic deformation in polycrystalline van der Waals (vdW) materials is challenging. Achieving such deformation is especially difficult in graphite because it is highly anisotropic. The development of sugar-derived isotropic nanostructured polycrystalline graphite (SINPG) is discussed herein. The structure of this material preserves the high in-plane rigidity and out-of-plane flexibility of graphene layers and enables prominent plasticity by activating the rotation of nanoscale (5-10 nm) grains. Thus, micrometer-sized SINPG samples demonstrate enhanced compressive strengths of up to 3.0 GPa and plastic strains of 30-50%. These findings suggest a new pathway for enabling plastic deformation in otherwise brittle vdW materials. This new class of nanostructured carbon materials is suitable for use in a broad range of fields, from semiconductor to aerospace applications.

15.
J Sep Sci ; 31(20): 3519-26, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18830958

RESUMO

A rapid and simple method has been developed for the screening and identification of natural antioxidants of Flos Lonicerae Japonicae (FLJ), derived from the flower buds of Lonicera japonica. The hypothesis is that upon reaction with 1,1-diphenyl-2-picrylhydrazyl (DPPH), the peak areas (PAs) of compounds with potential antioxidant effects in the HPLC chromatograms will be significantly reduced or disappeared, and the identity confirmation could be achieved by HPLC-DAD-TOF/MS hyphenated technique. Using the proposed approach, about 14 compounds in the FLJ extract were found to possess a potential antioxidant activity. They were identified as chlorogenic acid (1), 1-O-caffeoylquinic acid (1-O-CQA, 2), caffeic acid (4), 4-O-CQA (5), rutin (7), isoquercitrin (8), luteolin-7-O-glucoside (9), lonicerin (10), 4,5-O-dicaffeoylquinic acid (4,5-O-diCQA, 11), 3,5-O-diCQA (12), 1,3-O-diCQA (13), 3,4-O-diCQA (14), 1,4-O-diCQA (16), and luteolin (17). In addition, the free radical scavenging capacities of the available identified compounds were also investigated by HPLC assay. The results indicated that the compounds with PAs significantly decreasing were natural antioxidants, whereas those with PAs not changing presented no activities, which accordingly indicated that this newly proposed method could be widely applied for rapid screening and identification of natural antioxidants from complex matrices including Chinese herbal medicines.


Assuntos
Antioxidantes/análise , Cromatografia Líquida de Alta Pressão/métodos , Indicadores e Reagentes/química , Lonicera/química , Picratos/química , Extratos Vegetais/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Compostos de Bifenilo , Cromatografia Líquida de Alta Pressão/instrumentação , Medicamentos de Ervas Chinesas/química , Sequestradores de Radicais Livres/análise , Radicais Livres/química , Medicina Tradicional Chinesa , Estrutura Molecular , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/instrumentação
16.
Int J Surg ; 53: 5-11, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29555519

RESUMO

BACKGROUND: Intramedullary nailing (IMN) and plate have been reported as two effective devices for treating distal extra-articular fractures. However, reports of complications after fractures with use of different tibial fixation techniques in literature are controversial. Thus, we performed a meta-analysis of randomized controlled trials (RCTs) to compare IMN with plate for evaluating the safety and efficacy. METHODS: The studies were searched from PubMed, Embase, Web of science and the Cochrane Central Register of Controlled Trials by two reviewers up to August 2017. The quality of RCTs was assessed by Cochrane Handbook. Data were extracted from studies and analyzed by Review Manager 5.3. 95% confidence interval (CI) and risk ratio (RR) were calculated for dichotomous data. RESULTS: Eight RCTs with 482 patients were included in the meta-analysis. We found no statistically significant differences between IMN and plate on union time (SMD = -0.20, 95%CI -0.58 to 0.18, P = 0.3), delayed or nonunion (RR = 1.19, 95%CI 0.66 to 2.14, P = 0.56) and malunion (RR = 1.63, 95%CI 1.01 to 2.65, P = 0.05). IMN group had shorter operative time (P < 0.0001) and radiation time (P < 0.0001), lower incidence of wound complications (P = 0.0003) and higher rate of knee pain (P < 0.0001) than the plate group. CONCLUSION: The meta-analysis showed that intramedullary nailing reduced the time of surgery and radiation and the risk of wound complications compared with plate fixation. Furthermore, union time and union complications were common following both treatments. Overall, intramedullary nailing is found to be taken priority for distal tibial metaphyseal fractures. More RCTs are required to support current evidence.


Assuntos
Pinos Ortopédicos , Placas Ósseas , Fixação Intramedular de Fraturas/instrumentação , Fraturas da Tíbia/cirurgia , Adulto , Feminino , Fixação Intramedular de Fraturas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
17.
Medicine (Baltimore) ; 96(17): e6763, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28445306

RESUMO

BACKGROUND: Total joint arthroplasty (TJA) usually results in postoperative bleeding. Some randomized controlled trials (RCTs) and nonrandomized controlled trials (non-RCTs) have been performed to evaluate the effects of epinephrine on postoperative bleeding after TJA. However, this remained controversial about the efficacy and safety of epinephrine for postoperative bleeding in TJA. The objective of our meta-analysis was to compare the overall effect and safety of epinephrine and placebo for postoperative bleeding in TJA. METHODS: PubMed, Embase, and the Cochrane Library were searched to identify potentially relevant articles. RCTs or non-RCTs involving epinephrine and placebo for blood loss in total knee arthroplasty or total hip arthroplasty were included. Our study was performed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. RevMan v5.3 was used to analyze the relevant data. RESULTS: Four RCTs and 1 non-RCT involving 646 participants met the inclusion criteria. The overall pooled results from meta-analysis demonstrated that compared with control groups, epinephrine groups could significantly reduce the postoperative bleeding volume (mean difference [MD] = -168.42, 95% confidence interval [CI]: -272.37 to -64.47, P = 0.001). There was no significant difference in intraoperative bleeding volume between epinephrine and control groups (MD = -12.89, 95% CI: -53.45 to 27.69, P = 0.53). No significant difference was found between 2 groups in terms of postoperative hemoglobin loss (MD = -0.28, 95% CI: -0.66 to 0.10, P = 0.15). Compared with the control groups, no statistically significant difference was found in terms of postoperative transfusion rate in epinephrine groups (relative risk [RR] 0.86, 95% CI: 0.64-1.15, P = 0.31). In addition, the results of the meta-analysis also indicated no significant difference in terms of the incidence rate of deep venous thrombosis (DVT) between 2 groups (RR 0.28, 95% CI: 0.05-1.64, P = 0.16). CONCLUSION: The meta-analysis showed that epinephrine could significantly reduce postoperative bleeding volume in TJA without increasing the incidence of DVT. However, there was no significant reduction in intraoperative bleeding volume, postoperative hemoglobin loss, and transfusion rate after the administration of epinephrine. LIMITATIONS: In this study, a higher heterogeneity and a risk of selection bias may be present in postoperative hemoglobin loss. In addition, the sample size of the included studies was too small, so our findings need to be further validated with more high-quality and larger scale RCTs in the future. SYSTEMATIC REVIEW REGISTRATION NUMBER: None.


Assuntos
Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Epinefrina/uso terapêutico , Hemorragia Pós-Operatória/tratamento farmacológico , Vasoconstritores/uso terapêutico , Ensaios Clínicos como Assunto , Epinefrina/efeitos adversos , Humanos , Vasoconstritores/efeitos adversos
18.
ACS Appl Mater Interfaces ; 8(9): 6004-10, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26881823

RESUMO

It still remains very challenging to design proper heterostructures to enhance the electrochemical performance of transition metal oxide-based anode materials for lithium-ion batteries. Here, we synthesized the NiCoO2 nanosheets@SnO2 layer heterostructure supported by amorphous carbon nanotubes (ACNTs) which is derived from polymeric nanotubes (PNTs) by a stepwise method. The inner SnO2 layer not only provides a considerable capacity contribution but also produces the extra Li2O to promote the charge process of NiCoO2 and thus results in a rising cycling performance. Combining with the contribution of ACNTs backbone and ultrathin NiCoO2 nanosheets, the specific capacities of these one-dimensional nanostructures show an interesting gradually increasing trend even after 100 cycles at 400 mA g(-1) with a final result of 1166 mAh g(-1). This approach can be an efficient general strategy for the preparation of mixed-metal-oxide one-dimensional nanostructures and this innovative design of hybrid electrode materials provides a promising approach for batteries with improved electrochemical performance.

19.
Appl Spectrosc ; 57(8): 933-42, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14661836

RESUMO

Infrared (IR) spectra of a supramolecular assembly with an azobenzene derivative and intermolecular hydrogen bonds have been measured in the temperature range from 30 to 200 degrees C to investigate heat-induced structural changes and thermal stability. Principal component analysis (PCA) and two kinds of two-dimensional (2D) correlation spectroscopy, variable-variable (VV) 2D and sample-sample (SS) 2D spectroscopy, have been employed to analyze the observed temperature-dependent spectral variations. The PCA and SS 2D correlation analyses have demonstrated that the complete decoupling of hydrogen bonds in the supramolecular assembly occurs between 110 and 115 degrees C, which is in good agreement with the results of a differential scanning calorimetry (DSC) study for the heating process. The PCA of the IR spectra in the region of 3600-3100 cm(-1) has illustrated that there are at least four principal components for the different NH2 and CONH species in the present supramolecular system. The VV 2D correlation spectroscopy study has provided information about the structure and strength of hydrogen bonds of NH2 and CONH groups and their temperature-dependent variations. The different species of hydrogen-bonded NH2 and CONH groups in the supramolecular system can be clarified by the VV 2D correlation analysis. The VV 2D correlation analysis has also revealed the specific order of the temperature-induced changes in the hydrogen bonds of NH2 and CONH groups.


Assuntos
Compostos Azo/química , Análise de Componente Principal , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Temperatura Alta , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Molecular
20.
Cancer Biol Ther ; 12(5): 388-98, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21709440

RESUMO

Epithelial-mesenchymal transition (EMT) is a critical early event in tumorigenesis. The contribution of heparan sulfate (HS) to EMT has not been fully elucidated. HS D-glucosaminyl 3-O-sulfotransferase-3B1 (3-OST-3B1) participates in the final step of HS fine structure biosynthesis, whose involvement in cancer has yet to be determined. This study demonstrated that following treatment with trichostatin-A, a histone deacetylase inhibitor, 3-OST-3B1 gene expression was activated in the pancreatic cancer cell line, PANC-1. By chromatin immunoprecipitation analysis, permissive histone modifications including an increase in histone H3 lysine 9 monoactylation (H3 ac K9) but a decrease in methylated histone H3 (H3 me K9) were observed accompanying transcriptional activation of 3-OST-3B1. Functional, results revealed that increased 3-OST-3B1 levels were involved in the promotion of EMT processes. In vitro studies demonstrated that overexpression of 3-OST-3B1 in both pancreatic cancer cells and vascular endothelial cells could trigger an EMT-like phenotype as evidenced by the up-regulation of Snail at the mRNA and protein level, and its nuclear translocation. And 3-OST-3B1 appeared to be sufficient for the development of a more mesenchymal phenotype in vivo. Together, the results from this study unveiled a distinct function for 3-OST-3B1 as an EMT inducer in cancer and provided a link between histone modification and EMT modulation.


Assuntos
Transição Epitelial-Mesenquimal , Neoplasias Pancreáticas/enzimologia , Sulfotransferases/metabolismo , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Sequência de Bases , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Decitabina , Células Endoteliais/citologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Heparitina Sulfato/biossíntese , Histonas/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Metilação/efeitos dos fármacos , Neoplasias Pancreáticas/genética , RNA Mensageiro/biossíntese , Análise de Sequência de DNA , Fatores de Transcrição da Família Snail , Sulfotransferases/genética , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Ativação Transcricional
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