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1.
Environ Monit Assess ; 195(12): 1428, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37938430

RESUMO

Coal and grain complex areas influence the geochemical characterization of REEs through coal mining activities and agricultural production. However, there is a lack of relevant studies. In this study, we investigated the geochemical characterization and risk assessment of REEs in river sediments of the northern Anhui plain, a typical coal-grain composite area. The results showed that the average concentrations of ∑REE in the sediments ranged from 134.7 to 220.3 µg/g, and LREE was significantly enriched. Among the 14 REEs, Gd and Eu were the most enriched, with enrichment factors of 1.792 and 1.764, respectively. In addition, the differences in REEs content and enrichment between different rivers were related to the location of coal mines and the degree of population concentration. The average values of δCe and δEu in the sediments were 0.990 and 1.080, respectively, and most of the sampling sites showed a weak positive Ce, Eu anomaly. The results of Pearson's correlation and RDA redundancy analyses showed that Fe, Al, Mn and sand contributed more to the enrichment of REEs. The river sediments in the whole area had a slight potential ecological risk, with Eu (Er=13.05) and Lu (Er=14.07) having the highest potential risk. The ADD results also showed that the average daily dose of REEs by children was around 2.000 (µg/(kg·day)), which was significantly higher than that of adults. The results of this study can be used as a basis for the prevention and control of REEs in rivers in northern Anhui Province.


Assuntos
Metais Terras Raras , Rios , Adulto , Criança , Humanos , Monitoramento Ambiental , China , Carvão Mineral , Grão Comestível
2.
J Am Chem Soc ; 144(30): 13839-13850, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35862295

RESUMO

Despite their multifaceted advantages, inverted perovskite solar cells (PSCs) still suffer from lower power conversion efficiencies (PCEs) than their regular counterparts, which is largely due to recombination energy losses (Eloss) that arise from the chemical, physical, and energy level mismatches, especially at the interfaces between perovskites and fullerene electron transport layers (ETLs). To address this problem, we herein introduce an aminium iodide derivative of a buckybowl (aminocorannulene) that is molecularly layered at the perovskite-ETL interface. Strikingly, besides passivating the PbI2-rich perovskite surface, the aminocorannulene enforces a vertical dipole and enhances the surface n-type character that is more compatible with the ETL, thus boosting the electron extraction and transport dynamics and suppressing interfacial Eloss. As a result, the champion PSC achieves an excellent PCE of over 22%, which is superior compared to that of the control device (∼20%). Furthermore, the device stability is significantly enhanced, owing to a lock-and-key-like grip on the mobile iodides by the buckybowls and the resultant increase of the interfacial ion-migration barrier. This work highlights the potential of buckybowls for the multifunctional surface engineering of perovskite toward high-performance and stable PSCs.

3.
J Neuroeng Rehabil ; 19(1): 33, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35321725

RESUMO

BACKGROUND: Individuals with unilateral transfemoral amputation are prone to developing health conditions such as knee osteoarthritis, caused by additional loading on the intact limb. Such individuals who can run again may be at higher risk due to higher ground reaction forces (GRFs) as well as asymmetric gait patterns. The two aims of this study were to investigate manipulating step frequency as a method to reduce GRFs and its effect on asymmetric gait patterns in individuals with unilateral transfemoral amputation while running. METHODS: This is a cross-sectional study. Nine experienced track and field athletes with unilateral transfemoral amputation were recruited for this study. After calculation of each participant's preferred step frequency, each individual ran on an instrumented treadmill for 20 s at nine different metronome frequencies ranging from - 20% to + 20% of the preferred frequency in increments of 5% with the help of a metronome. From the data collected, spatiotemporal parameters, three components of peak GRFs, and the components of GRF impulses were computed. The asymmetry ratio of all parameters was also calculated. Statistical analyses of all data were conducted with appropriate tools based on normality analysis to investigate the main effects of step frequency. For parameters with significant main effects, linear regression analyses were further conducted for each limb. RESULTS: Significant main effects of step frequency were found in multiple parameters (P < 0.01). Both peak GRF and GRF impulse parameters that demonstrated significant main effects tended towards decreasing magnitude with increasing step frequency. Peak vertical GRF in particular demonstrated the most symmetric values between the limbs from - 5% to 0% metronome frequency. All parameters that demonstrated significant effects in asymmetry ratio became more asymmetric with increasing step frequency. CONCLUSIONS: For runners with a unilateral transfemoral amputation, increasing step frequency is a viable method to decrease the magnitude of GRFs. However, with the increase of step frequency, further asymmetry in gait is observed. The relationships between step frequency, GRFs, and the asymmetry ratio in gait may provide insight into the training of runners with unilateral transfemoral amputation for the prevention of injury.


Assuntos
Amputados , Membros Artificiais , Corrida , Amputação Cirúrgica , Fenômenos Biomecânicos , Estudos Transversais , Marcha , Humanos
4.
BMC Genomics ; 22(1): 463, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34157978

RESUMO

BACKGROUND: The amino acid/auxin permease (AAAP) family represents a class of proteins that transport amino acids across cell membranes. Members of this family are widely distributed in different organisms and participate in processes such as growth and development and the stress response in plants. However, a systematic comprehensive analysis of AAAP genes of the pepper (Capsicum annuum) genome has not been reported. RESULTS: In this study, we performed systematic bioinformatics analyses to identify AAAP family genes in the C. annuum 'Zunla-1' genome to determine gene number, distribution, structure, duplications and expression patterns in different tissues and stress. A total of 53 CaAAAP genes were identified in the 'Zunla-1' pepper genome and could be divided into eight subgroups. Significant differences in gene structure and protein conserved domains were observed among the subgroups. In addition to CaGAT1, CaATL4, and CaVAAT1, the remaining CaAAAP genes were unevenly distributed on 11 of 12 chromosomes. In total, 33.96% (18/53) of the CaAAAP genes were a result of duplication events, including three pairs of genes due to segmental duplication and 12 tandem duplication events. Analyses of evolutionary patterns showed that segmental duplication of AAAPs in pepper occurred before tandem duplication. The expression profiling of the CaAAAP by transcriptomic data analysis showed distinct expression patterns in various tissues and response to different stress treatment, which further suggest that the function of CaAAAP genes has been differentiated. CONCLUSIONS: This study of CaAAAP genes provides a theoretical basis for exploring the roles of AAAP family members in C. annuum.


Assuntos
Capsicum , Capsicum/genética , Capsicum/metabolismo , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Ácidos Indolacéticos , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
Inorg Chem ; 60(17): 13269-13277, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34404212

RESUMO

In this study, Cu2Se1-xSx (x = 0.1, 0.3, and 0.5) alloy powders were prepared by the hydrothermal synthesis method. In the subsequent sintering process, the spontaneous in situ phase separation process of the sample forms a two-phase hybrid structure. The generated Cu2S precipitates in the Cu2Se matrix noticeably enhance phonon scattering, which is beneficial for low thermal conductivity without significantly affecting the electrical transport performance. Ultimately, an optimized thermoelectric performance was obtained in Cu2Se0.9S0.1, reaching a peak zT value of 1.43 at 773 K, the optimum value among the Cu-Se-S systems at this temperature.

6.
Qual Life Res ; 30(5): 1249-1265, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33459972

RESUMO

PURPOSE: Chemotherapy exerts adverse effects on physical, psychological and social functioning in women with breast cancer, which may trigger adaptive activities. For a better understanding of the experience of symptoms associated with chemotherapy and the development of targeted interventions, this study aimed to (a) explore the patient experience of chemotherapy, (b) identify patients' strategies to cope with the side effects and distress and (c) explore the link between their experience and coping strategies. METHODS: Qualitative studies were included if they explored the experience or coping strategies of women with breast cancer receiving chemotherapy. Instruments from the Joanna Briggs Institute were used to critically appraise the methodological quality, extract data and aggregate findings from the included studies. RESULTS: Twelve studies presenting findings from 184 women with breast cancer who had received chemotherapy were included in this review. Three synthesized findings were identified from 8 categories based on 91 original findings: (1) Women living with chemotherapy experienced various stressful side effects, and their lives were changed. (2) Supportive care to address needs is essential to help women get through this difficult time. (3) They engaged in numerous types of coping strategies to deal with side effects and adapt to this difficult journey. Moreover, the link between experience of chemotherapy and coping strategies is based on the Lazarus' stress and coping theory. CONCLUSIONS: Although the experience of women with breast cancer undergoing chemotherapy is individualized, we concluded that the distressing experience related to chemotherapy as a stimulus was viewed as a stressor that demands coping or adaptation. Based on the Lazarus stress and coping theory, the ability of a woman to appraise how chemotherapy changed her life and how she appraises her resources to cope with chemotherapy are essential. The results highlight that pre-chemotherapy care programmes, information support systems, social support groups and individual effective coping strategies are helpful in reducing treatment-related distress levels and enhance self-care effects at home.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Qualidade de Vida/psicologia , Adulto , Idoso , Neoplasias da Mama/psicologia , Feminino , Humanos , Pessoa de Meia-Idade , Pesquisa Qualitativa
7.
Int J Nurs Pract ; 27(3): e12886, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32926505

RESUMO

BACKGROUND: Child health research comprises complex ethical considerations. Understanding the extent to which the ethical process is reported in child health research is needed to improve reporting. AIMS: To identify reportage of ethical considerations in child health research in leading nursing and paediatric journals. METHODS: All child health research published between 2015 and 2019 in 10 leading nursing journals and two paediatric journals were retrieved and critically appraised for the reportage of informed consent and ethical approval. RESULTS: Eight hundred and fifty-one child health research papers were included. Although 544 (79.9%) of the prospective studies mentioned informed consent, only 300 (55.2%) reported that written informed consent was obtained from the participants. Overall, 748 (87.9%) of child health research papers noted obtaining research ethics committee approval. Articles that mentioned financial support were significantly more likely to report informed consent and ethical approval than unfunded studies (all P < 0.001). Prospective studies showed higher rates of reportage of ethical approval compared to retrospective studies (P = 0.027). Rates of child consent (assent) obtained in different age groups of children ranged from 29.6% to 66.3%. CONCLUSION: Despite improvements in the reportage of ethical review and approval processes in child health research, consistent and transparent reports are still lacking.


Assuntos
Pesquisa Biomédica , Saúde da Criança , Ética em Enfermagem , Enfermagem Pediátrica/ética , Publicações Periódicas como Assunto , Criança , Humanos , Consentimento Livre e Esclarecido , Fator de Impacto de Revistas , Estudos Retrospectivos
8.
Biol Reprod ; 103(4): 866-879, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32582940

RESUMO

Fetal growth restriction (FGR) is a condition in which a newborn fails to achieve his or her prospective hereditary growth potential. This condition is associated with high newborn mortality, second only to that associated with premature birth. FGR is associated with maternal, fetal, and placental abnormalities. Although the placenta is considered to be an important organ for supplying nutrition for fetal growth, research on FGR is limited, and treatment through the placenta remains challenging, as neither proper uterine intervention nor its pathogenesis have been fully elucidated. Yes-associated protein (YAP), as the effector of the Hippo pathway, is widely known to regulate organ growth and cancer development. Therefore, the correlation of the placenta and YAP was investigated to elucidate the pathogenic mechanism of FGR. Placental samples from humans and mice were collected for histological and biomechanical analysis. After investigating the location and role of YAP in the placenta by immunohistochemistry, we observed that YAP and cytokeratin 7 have corresponding locations in human and mouse placentas. Moreover, phosphorylated YAP (p-YAP) was upregulated in FGR and gradually increased as gestational age increased during pregnancy. Cell function experiments and mRNA-Seq demonstrated impaired YAP activity mediated by extracellular signal-regulated kinase inhibition. Established FGR-like mice also recapitulated a number of the features of human FGR. The results of this study may help to elucidate the association of FGR development with YAP and provide an intrauterine target that may be helpful in alleviating placental dysfunction.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Movimento Celular/fisiologia , Fatores de Transcrição/metabolismo , Trofoblastos/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Linhagem Celular , Embrião de Mamíferos/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Humanos , Indazóis/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Piperazinas/farmacologia , Placenta , Gravidez , Fatores de Transcrição/genética , Regulação para Cima , Proteínas de Sinalização YAP
9.
Support Care Cancer ; 28(9): 4327-4336, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31912364

RESUMO

PURPOSE: Chemotherapy-induced alopecia is a common and emotionally traumatic side effect on breast cancer patients. In order to make up for the deficiency of measuring tools in China, our study aims at translating the chemotherapy-induced alopecia distress scale (CADS) into Chinese and evaluating the psychometric properties of the Chinese version of CADS (CADS-C) in breast cancer patients. METHODS: The validity and reliability of CADS-C were measured by a questionnaire survey among 301 breast cancer patients from Chinese mainland. Construct validity was assessed through factor analysis and contrasted group comparisons. The validity of the content was examined by an experts group. The internal consistency and test-retest reliability were evaluated by calculating Cronbach's alpha and the intraclass correlation coefficient. RESULTS: The content validity index was 0.94; a structure with three factors was revealed by exploratory factor analysis which explained 65.40% of the variance and proved by confirmatory factor analysis. The contrasted group comparisons showed significant differences among different degrees of alopecia. The average variance extracted and composite reliability and correlations between CADS and body image, quality of life and self-esteem proved the convergent validity. The Cronbach's alpha and the intraclass correlation coefficient of the total scale were 0.90 and 0.89 respectively, indicating satisfactory internal consistency and time stability. CONCLUSION: The scale appears to be a reliable and valid tool to measure chemotherapy-induced alopecia distress among breast cancer patients in China.


Assuntos
Alopecia/induzido quimicamente , Alopecia/psicologia , Antineoplásicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Psicometria/métodos , Adulto , Idoso , Antineoplásicos/administração & dosagem , Povo Asiático , Imagem Corporal , Estudos Transversais , Análise Fatorial , Feminino , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Reprodutibilidade dos Testes , Tradução
10.
J Nurs Scholarsh ; 52(6): 688-695, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32890425

RESUMO

PURPOSE: The confidence in a study will be reduced due to the incorrect representation of statistical results. However, it is unknown to what extent p values are incorrectly represented in published nursing journals. The study aims to evaluate the articles in 30 nursing journals in terms of the error in reporting of p values (p = .000). DESIGN AND METHODS: This was a bibliometric analysis. All papers published in 10 leading nursing journals (between 2015 and 2019), the 10 bottom nursing journals (2019), and 10 selected key nursing journals (2019) indexed in the Science Citation Index Journal Citation Reports were reviewed to detect errors in reporting of p values (p = .000). RESULTS: A total of 3,788 papers were reviewed. Notably, it was found that 93.3% (28/30) of the nursing journals contained incorrect representation of p values (p = .000). The reporting rate of these journals ranges from 0% to 57.1%, with an overall rate of 12.8% (486/3,788). In addition, the rate of incorrect representation of p values (p = .000) showed no statistically significant difference between different publication years (Χ2 = 4.976, p = .290). However, the rate of reporting was different between study types, journals, and regions (p = .007, p = .020, and p < .001, respectively). CONCLUSIONS: The incorrect representation of p values is common in nursing journals. CLINICAL RELEVANCE: We recommend that both publishers and researchers be responsible for preventing statistical errors in manuscripts. Furthermore, various kinds of statistical training methods should be adopted to ensure that nurses and journal reviewers have enough statistical literacy.


Assuntos
Pesquisa em Enfermagem , Relatório de Pesquisa/normas , Estatística como Assunto , Bibliometria , Humanos
11.
BMC Med Educ ; 20(1): 280, 2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32838782

RESUMO

BACKGROUND: Evidence-based practice (EBP) education or training are considered fundamental to building and strengthening an EBP culture, as well as to encouraging evidence-based academic and clinical practice in the nursing community. However, few valid and reliable instruments are available for the assessment of EBP teaching and learning in clinical nurses in China. Translation, reliability, and validity testing of the English Evidence-Based Practice Profile Questionnaire (EBP2Q), which has strong psychometric properties, may encourage evaluation and promote the implementation of EBP in Mainland China. METHODS: Based on established guidelines for the development of questionnaires, the English EBP2Q was translated and cross-culturally adapted. The Chinese version of the EBP2Q (EBP2Q-C) was validated using a sample of 543 nurses. Structural validity was evaluated through exploratory factor analysis and confirmatory factor analysis, and the questionnaire was tested for convergent and criterion validity. The internal consistency and test-retest reliability were also evaluated. RESULTS: The content validity index demonstrated good content validity (≥0.98). An eight-factor structure was obtained in the exploratory factor analysis, and verified by a three-order factor model from the confirmatory factor analysis (χ2/df = 2.001; RMSEA = 0.065; SRMR = 0.077; and CFI = 0.884). The Spearman's rank correlation analysis of the EBP2Q-C with the Evidence-Based Practice Questionnaire showed moderate correlations for Practice (0.58) and Confidence (0.68) and a low correlation for Sympathy (0.32). Criterion validity was demonstrated by significant differences in terms of nurses' highest education, present position, EBP training, involvement in research programs, and level of understanding of English. Both the overall Cronbach's α and the Cronbach's α for the domains exceeded 0.70. The intraclass correlation coefficients for the domains ranged between 0.75 and 0.96, indicating satisfactory repeatability. CONCLUSIONS: Except for the convergent validity of the Sympathy domain, the EBP2Q-C provided evidence of validity and reliability. Therefore, it can be applied in EBP education or training assessment in Mainland China.


Assuntos
Prática Clínica Baseada em Evidências , Traduções , China , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
12.
BMC Plant Biol ; 19(1): 208, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31109298

RESUMO

BACKGROUND: Cotton fiber is a single cell that arises from the epidermis of ovule. It is not only a main economic product of cotton, but an ideal material for studying on the growth and development of plant cell. Our previous study indicated that phytosterol content and the ratio of campesterol to sitosterol fluctuated regularly in cotton fiber development. However, what effects of modified phytosterol content and composition on the growth and development of cotton fiber cell is unknown. In this study, we overexpressed the GhSMT2-1, a cotton homologue of sterol C-24 methyltransferase 2 gene in transgenic upland cotton plants to modify phytosterol content and composition in fiber cells and investigated the changes on fiber elongation and secondary cell wall deposition. RESULTS: GhSMT2-1 overexpression led to changes of phytosterol content and the ratio of campesterol to sitosterol in fiber cell. At the rapid elongation stage of fiber cell, total phytosterol and sitosterol contents were increased while campesterol content was decreased in transgenic fibers when compared to control fibers. Accordingly, the ratio of campesterol to sitosterol declined strikingly. Simultaneously, the transgenic fibers were shorter and thicker than control fibers. Exogenous application of sitosterol or campesterol separately inhibited control fiber cell elongation in cotton ovule culture system in vitro. In addition, campesterol treatment partially rescued transgenic fiber elongation. CONCLUSION: These results elucidated that modification of phytosterol content and composition influenced fiber cell elongation and secondary cell wall formation. High sitosterol or low ratio of campesterol to sitosterol suppresses fiber elongation and/or promote secondary cell wall deposition. The roles of sitosterol and campesterol were discussed in fiber cell development. There might be a specific ratio of campesterol to sitosterol in different developmental stage of cotton fibers, in which GhSMT2-1 play an important role. Our study, at a certain degree, provides novel insights into the regulatory mechanisms of fiber cell development.


Assuntos
Gossypium/química , Gossypium/fisiologia , Fitosteróis/química , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Crescimento Celular , Parede Celular , Fibra de Algodão , Gossypium/genética , Metiltransferases/genética , Metiltransferases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia
13.
BMC Med Ethics ; 20(1): 94, 2019 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-31805918

RESUMO

BACKGROUND: Ethical considerations play a prominent role in the protection of human subjects in clinical research. To date the disclosure of ethical protection in clinical research published in the international nursing journals has not been explored. Our research objective was to investigate the reporting of ethical approval and informed consent in clinical research published in leading international nursing journals. METHODS: This is a retrospective observational study. All clinical research published in the five leading international nursing journals from the SCI Journal Citation Reports between 2015 and 2017 were retrieved to evaluate for evidence of ethical review. RESULTS: A total of 2041 citations have been identified from the contents of all the five leading nursing journals that were published between 2015 and 2017. Out of these, 1284 clinical studies have been included and text relating to ethical review has been extracted. From these, most of prospective clinical studies (87.5%) discussed informed consent. Only half of those (52.9%) reported that written informed consent had been obtained; few (3.6%) reported oral consent, and few (6.8%) used other methods such as online consent or completion and return of data collection (such as surveys) to denote assent. Notably, 36.2% of those did not describe the method used to obtain informed consent and merely described that "consent was obtained from participants or participants agreed to join in the research". Furthermore, whilst most of clinical studies (93.7%) mentioned ethical approval; 92.5% of those stated the name of ethical committee and interestingly, only 37.1% of those mentioned the ethical approval reference. The rates of reporting ethical approval were different between different study type, country, and whether financial support was received (all P < 0.05). CONCLUSION: The reporting of ethics in leading international nursing journals demonstrates progress, but improvement of the transparency and the standard of ethical reporting in nursing clinical research is required.


Assuntos
Pesquisa Biomédica , Consentimento Livre e Esclarecido , Cuidados de Enfermagem , Editoração/ética , Confidencialidade/ética , Políticas Editoriais , Publicações Periódicas como Assunto , Estudos Retrospectivos
14.
Cell Physiol Biochem ; 49(2): 578-594, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30165353

RESUMO

BACKGROUND/AIMS: Preeclampsia (PE) has long been assumed to be an ischemic disease of the placenta, although there is limited evidence as to how the ischemia impacts on the placenta. AMP-activated protein kinase (AMPK) is a key regulator of cellular energy metabolism and plays an important role in a variety of ischemic diseases by enhancing energy production. The present study investigated placental metabolism in PE, and the role of AMPK in regulating trophoblast function. METHODS: placentas from normal and PE complicated pregnancies were subjected to GC-MS to identify fatty acids (FA) metabolic fingerprints, and total FA oxidation was assessed by malondialdehyde (MDA) measurement. The AMPK-ACC signaling pathway was assessed by q-PCR and Western Blotting. HTR8/SVneo trophoblast cultures were exposed to different oxygenation conditions to establish an in vitro PE cell model; further analysis by GC-MS for metabolite profiling was then undertaken. Trophoblasts invasion was assessed by a matrigel transwell assay in the presence/absence of AMPK expression and after manipulations of AMPK activity, and then further validated by human villi outgrowth experiments. RESULTS: AMPK phosphorylation and MDA production were significantly elevated in placentas from pregnancies complicated by PE. Metabolism of cis double bond FA was inhibited while trans double bond FA metabolism was promoted in PE placentas. HTR8/SVneo cell culture conditions of persistent low oxygenation mimicked the hyper-activation of AMPK and enhanced the FA oxidation that was observed in PE. AMPK activation impaired trophoblast invasion, while AMPK inhibition promoted trophoblast invasion. CONCLUSION: PE complicated placentas are associated with AMPK hyper-activation and consequent alterations in FA oxidation, which inhibit trophoblast invasion.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Ácidos Graxos/metabolismo , Pré-Eclâmpsia/patologia , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP/genética , Adulto , Movimento Celular , Células Cultivadas , Cobalto/farmacologia , Análise Discriminante , Ácidos Graxos/análise , Feminino , Humanos , Análise dos Mínimos Quadrados , Malondialdeído/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Fosforilação/efeitos dos fármacos , Placenta/citologia , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Gravidez , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Trofoblastos/citologia , Trofoblastos/metabolismo
15.
Org Biomol Chem ; 15(38): 8091-8101, 2017 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-28905964

RESUMO

Near-infrared (NIR) fluorescent probes are advantageous over visible ones, for they can avoid the interference from the short-wavelength background emission in biological systems. However, there are a very limited number of NIR probes that can specifically label target proteins in living cells. In this work, a series of long-wavelength dyes (N-NIR, S-NIR, and K-NIR) analogous to the novel Changsha NIR family are synthesized conveniently through a new approach that is different from the previously reported one. These three dyes have similar conjugation structures but exhibit tunable photophysical properties. N-NIR and S-NIR have large extinction coefficients over 100 000, and high fluorescence quantum yields. Although NIR absorption and emission of K-NIR are inferior to the former two, it emits in a much longer wavelength region. And all the three dyes can easily pass through the cell membranes to obtain the high-resolution NIR fluorescence images. Furthermore, N-NIR is chosen as the NIR fluorophore to develop a protein-labeling reagent PYBG-D, since it demonstrates the highest fluorescence quantum yield of up to 0.4 (in methanol). PYBG-D is efficiently synthesized through Sonogashira coupling between bromo-substituted N-NIR and alkyne-substituted benzylguanine (PYBG). The conjugate PYBG-D proves to be a specific and efficient label for O6-alkylguanine-DNA alkyltransferase (SNAP-tag) that fused to target proteins in living cells, which contributes to high resolution NIR fluorescence images under a laser confocal microscope.


Assuntos
Corantes Fluorescentes/química , Animais , Técnicas Biossensoriais , Linhagem Celular , Membrana Celular , Sobrevivência Celular , Humanos , Modelos Moleculares , Estrutura Molecular , Conformação Proteica , Espectrofotometria Infravermelho
16.
Artigo em Inglês | MEDLINE | ID: mdl-38517721

RESUMO

The primary goal of rehabilitation for individuals with lower limb amputation, particularly those with unilateral transfemoral amputation (uTFA), is to restore their ability to walk independently. Effective control of the center of pressure (COP) during gait is vital for maintaining balance and stability, yet it poses a significant challenge for individuals with uTFA. This study aims to study the COP during gait in individuals with uTFA and elucidate their unique compensatory strategies. This study involved 12 uTFA participants and age-matched non-disabled controls, with gait and COP trajectory data collected using an instrumented treadmill. Gait and COP parameters between the control limb (CL), prosthetic limb (PL), and intact limb (IL) were compared. Notably, the mediolateral displacement of COP in PL exhibited significant lateral displacement compared to the CL from 30% to 60% of the stance. In 20% to 45% of the stance, the COP forward speed of PL was significantly higher than that of the IL. Furthermore, during the initial 20% of the stance, the vertical ground reaction force of PL was significantly lower than that of IL. Additionally, individuals with uTFA exhibited a distinct gait pattern with altered duration of loading response, single limb support, pre-swing and swing phases, and step time. These findings indicate the adaptability of individuals with uTFA in weight transfer, balance control, and pressure distribution on gait stability. In conclusion, this study provides valuable insights into the unique gait dynamics and balance strategies of uTFA patients, highlighting the importance of optimizing prosthetic design, alignment procedures, and rehabilitation programs to enhance gait patterns and reduce the risk of injuries due to compensatory movements.


Assuntos
Amputados , Membros Artificiais , Humanos , Amputados/reabilitação , Fenômenos Biomecânicos , Marcha/fisiologia , Caminhada/fisiologia , Amputação Cirúrgica
17.
Prosthet Orthot Int ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38330181

RESUMO

Jumping is involved in a wide range of sports and activities, and foot orthoses (FO) are suggested to enhance performance and prevent injury. The aim of this systematic review was to investigate whether using FO with different modifications affects jump landing biomechanics and improves performance in healthy individuals. The search strategy included 7 databases that identified 19 studies. The study quality was evaluated using a modified Downs and Black index. The primary outcome measures were joint kinematics, kinetics, muscle activity, vertical jump height, and horizontal jump distance. Our findings indicated that incorporating arch support with a rearfoot post and softer forefoot region into FO may improve several biomechanical variables during jump landing activities. Improvements in vertical ground reaction force loading rates, knee and ankle kinematics, and muscle cocontraction during jumping with FO could enhance jumping performance. In addition, improvements in hip, knee, ankle, and tibial kinematics and vertical ground reaction force loading rates during landing could reduce impact forces and related injuries. Although a limited number of studies have addressed the effects of FO on vertical jump height and horizontal jump distance, inserting such FO inside shoes with optimum bending stiffness could facilitate jumping performance. A rigorous exploration of the effect and mechanism of FO designs on jumping performance could benefit jumping-related activities and prevent ankle and knee injuries.

18.
R Soc Open Sci ; 11(3): 231854, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38545618

RESUMO

This study aimed to compare the ground reaction forces (GRFs) and spatio-temporal parameters as well as their asymmetry ratios in gait between individuals wearing a transfemoral prosthetic simulator (TFSim) and individuals with unilateral transfemoral amputation (TFAmp) across a range of walking speeds (2.0-5.5 km h-1). The study recruited 10 non-disabled individuals using TFSim and 10 individuals with unilateral TFAmp using a transfemoral prosthesis. Data were collected using an instrumented treadmill with built-in force plates, and subsequently, the GRFs and spatio-temporal parameters, as well as their asymmetry ratios, were analysed. When comparing the TFSim and TFAmp groups, no significant differences were found among the gait parameters and asymmetry ratios of all tested metrics except the vertical GRFs. The TFSim may not realistically reproduce the vertical GRFs during the weight acceptance and push-off phases. The structural and functional variations in prosthetic limbs and components between the TFSim and TFAmp groups may be primary contributors to the difference in the vertical GRFs. These results suggest that TFSim might be able to emulate the gait of individuals with TFAmp regarding the majority of spatio-temporal and GRF parameters. However, the vertical GRFs of TFSim should be interpreted with caution.

19.
R Soc Open Sci ; 10(3): 221198, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36908994

RESUMO

Understanding the sprinting patterns of individuals with unilateral transfemoral amputation (uTFA) is important for designing improved running-specific prostheses and for prosthetic gait rehabilitation. Continuous relative phase (CRP) analysis acquires clues from movement kinematics and obtains insights into the sprinting coordination of individuals with uTFA. Seven individuals with uTFA sprinted on a 40 m runway. The spatio-temporal parameters, joint and segment angles of the lower limbs were obtained, and CRP analysis was performed on thigh-shank and shank-foot couplings. Subsequently, the asymmetry ratios of the parameters were calculated. Statistical analyses were performed between the lower limbs. Significant differences in the stance time, stance phase percentage, ankle joint angles and CRP of the shank-foot coupling (p < 0.05) were observed between the lower limbs. The primary contributor to these differences could be the structural differences between the lower limbs. Despite the presence of different coordination features in the stance and swing phases between the lower limbs, no significant difference in the coordination patterns of the thigh-shank coupling was observed. This may be a compensation strategy for achieving coordination patterns with improved symmetry between the lower limbs. The results of this study provide novel insights into the sprinting movement patterns of individuals with uTFA.

20.
Materials (Basel) ; 16(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37241381

RESUMO

The CoCrFeNiMn high-entropy alloys were treated by powder-pack boriding to improve their surface hardness and wear resistance. The variation of boriding layer thickness with time and temperature was studied. Then, the frequency factor D0 and diffusion activation energy Q of element B in HEA are calculated to be 9.15 × 10-5 m2/s and 206.93 kJ/mol, respectively. The diffusion behavior of elements in the boronizing process was investigated and shows that the boride layer forms with the metal atoms diffusing outward and the diffusion layer forms with the B atoms diffusing inward by the Pt-labeling method. In addition, the surface microhardness of CoCrFeNiMn HEA was significantly improved to 23.8 ± 1.4 Gpa, and the friction coefficient was reduced from 0.86 to 0.48~0.61.

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