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The deregulation of long noncoding RNAs (lncRNAs) holds great potential in the treatment of multiple cancers, including pancreatic cancer (PC). However, the specific molecular mechanisms by which LINC01133 contributes to pancreatic cancer remain unknown. Subsequent to bioinformatics analysis, we predicted and analyzed differentially expressed lncRNAs, microRNAs, and genes in pancreatic cancer. We determined the expression patterns of LINC01133, miR-1299, and insulin-like growth factor 2 mRNA binding protein 3 (IGF2BP3) in pancreatic cancer cells, and validated their interactions through luciferase reporter and RNA immunoprecipitation assays. We implemented loss-of-function and gain-of-function experiments for LINC01133, miR-1299, and IGF2BP3 to assay their potential effects on pancreatic cancer cell functions. We observed high expression of LINC01133 and IGF2BP3, but low expression of miR-1299, in pancreatic cancer cells. Furthermore, we found that LINC01133 enhances IGF2BP3 through binding with miR-1299. Silencing LINC01133 or IGF2BP3 and/or overexpressing miR-1299 limited pancreatic cancer cell proliferation, invasion, epithelial-mesenchymal transition, and suppressed tumorigenic abilities in mice lacking T cells (nude mice). Overall, our findings identified that silencing LINC01133 downregulates IGF2BP3 by upregulating miR-1299 expression, ultimately leading to the prevention of pancreatic cancer.
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MicroRNAs , Neoplasias Pancreáticas , RNA Longo não Codificante , Animais , Camundongos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Camundongos Nus , Linhagem Celular Tumoral , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Movimento CelularRESUMO
The noncovalent interactions between formamide (FM) and the heteroaromatic compounds (furan and thiophene) were investigated through microwave spectroscopy and theoretical calculations. Each of the investigated complexes exhibits a single rotational spectrum corresponding to the lowest energy structure predicted theoretically. In the detected structures, N-H···O and C-H···O hydrogen bonds dominate the complexation between FM and furan, resulting in a planar configuration. Conversely, a superposed configuration linked by a N-H···π hydrogen bond and CâO···π contact is observed for the FM-thiophene complex. In both cases, hydrogen bonding interactions with N-H as proton donor rank as the dominant forces, and the interaction energy of N-H···O is larger than that of N-H···π. It was found that the electrostatic component is the largest contributor to the attraction between FM and furan, while the dispersion component is the most significant attractive factor in the FM-thiophene complex. These findings highlight the distinct features of hydrogen bonding interactions of amides with heteroaromatics in the studied complexes.
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The C-Hâ¯S-S interactions are fundamentally important to understand the stability of biomacromolecules and their binding with small molecules, but they are still underappreciated. Herein, we characterized the C-Hâ¯S-S interactions in model molecular complexes. The rotational spectra of the complexes of diethyl disulfide with CH2CH2 and CH2CHF were measured and analyzed. All the detected structures are mainly stabilized by a C-Hâ¯S-S hydrogen bond, providing stabilization energies of 2.3-7.2 kJ mol-1. Incidental C-Hâ¯π or C-Hâ¯F interactions enhance the stabilization of the complexes. London dispersion, which accounts for 54%-68% of the total attractions, is the main driving force of stabilization. The provided bonding features of C-Hâ¯S-S are crucial for understanding the stabilizing role of this type of interaction in diverse processes such as supramolecular recognition, protein stability, and enzyme activity.
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Background: While endometriosis is commonly perceived as a benign gynecological condition, its aggressive biological behavior underscores the critical importance of effective postoperative management. Our research is driven by the ultimate goal of improving postoperative recovery, reducing recurrence rates, and enhancing the overall well-being and fertility of individuals affected by endometriosis. To achieve these objectives, this study conducts a systematic assessment of the therapeutic efficacy of traditional Chinese medicine (TCM) in the context of endometriosis through a comprehensive meta-analysis. By rigorously evaluating both the effectiveness and safety of TCM treatments, our research aims to offer valuable insights that can form a solid foundation for informed clinical decision-making in endometriosis management. The potential impact of our findings extends to enhancing the quality of life for patients and addressing fertility concerns, thereby underscoring the clinical relevance and significance of our research endeavors. Methods: We conducted a literature search from January 2000 to May 2022 using the keywords "TCM, endometriosis, efficacy, safety, infertility, and efficacy analysis." The search covered databases [mention specific databases used, e.g., PubMed, Scopus, etc.]. The retrieved studies encompassed the years within the specified time frame (January 2000 to May 2022), providing a comprehensive overview of relevant literature. The risk of bias was assessed utilizing RevMan 5.3 and Stata software. To evaluate literature heterogeneity, we employed the Q-test and assessed heterogeneity (I2). Results: The results demonstrated low heterogeneity in the efficacy of TCM for treating endometriosis (I2 = 13.76%), a similarly low heterogeneity in the pregnancy rate of endometriosis treated with TCM (I2 = 30.54%), and no heterogeneity in the abortion rate for endometriosis treated with TCM (I2 = 0.00%). However, it is noteworthy that the heterogeneity of adverse reactions associated with TCM treatment for endometriosis was relatively high (I2 = 67.11%). Conclusion: The meta-analysis results confirmed that TCM treatment exhibited better efficacy in managing endometriosis, resulting in higher pregnancy rates, lower abortion rates, and a reduced probability of adverse reactions. These findings not only hold promise for improving the overall quality of life for patients but also offer practical implications for clinicians. The positive outcomes suggest that integrating TCM into endometriosis management could be considered as part of a comprehensive approach to enhance treatment effectiveness and minimize adverse effects, thereby providing clinicians and patients with valuable insights for informed decision-making.
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PURPOSE: Children with acute leukemia have suffered from a considerable symptom burden during chemotherapy. However, few studies have focused on exploring the mechanisms among symptoms in children with acute leukemia. Our study aims to explore core symptoms and describe the interrelationships among symptoms in children with acute leukemia during chemotherapy. METHODS: From January 2021 to March 2023, 469 children with acute leukemia were recruited from 20 Chinese cities. The Memorial Symptom Assessment Scale 10-18 (MSAS 10-18) was used to evaluate the prevalence and severity of symptoms during chemotherapy. A network analysis was performed by the R software based on 31 symptoms. Centrality indices and density were used to explore core symptoms and describe interrelationships among symptoms in the network during chemotherapy. RESULTS: Worrying and feeling irritable were the central symptoms across the three centrality indices, including strength, closeness, and betweenness. Lack of energy was the most prevalent symptom; however, it was less central than other symptoms. The density of the "induction and remission" network significantly differed from other cycles' counterparts (p < 0.001). Global strength was greater in the " ≥ 8 years group " network than the " < 8 years group " network (p = 0.023). CONCLUSION: Network analysis provides a novel approach to identifying the core symptoms and understanding the interrelationships among symptoms. Our study indicates the need to assess emotional symptoms in children with acute leukemia during chemotherapy, especially during the induction and remission phases, as well as in older children. Future research is imperative to construct trajectories of dynamic symptom networks and centrality indices in longitudinal data to investigate the causal relationships among symptoms.
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Antineoplásicos , Leucemia , Criança , Humanos , Povo Asiático , Emoções , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/epidemiologia , Software , Antineoplásicos/uso terapêutico , Leucemia/diagnóstico , Leucemia/tratamento farmacológico , Leucemia/psicologia , Doença Aguda , ChinaRESUMO
BACKGROUND: In the face of unprecedented challenges because of coronavirus disease 2019, interdisciplinary pediatric oncology teams have developed strategies to continue providing high-quality cancer care. This study explored factors contributing to health care resilience as perceived by childhood cancer providers in all resource level settings. METHODS: This qualitative study consisted of 19 focus groups conducted in 16 countries in 8 languages. Seven factors have been previously defined as important for resilient health care including: 1) in situ practical experience, 2) system design, 3) exposure to diverse views on the patient's situation, 4) protocols and checklists, 5) teamwork, 6) workarounds, and 7) trade-offs. Rapid turn-around analysis focused on these factors. RESULTS: All factors of health care resilience were relevant to groups representing all resource settings. Focus group participants emphasized the importance of teamwork and a flexible and coordinated approach to care. Participants described collaboration within and among institutions, as well as partnerships with governmental, private, and nonprofit organizations. Hierarchies were advantageous to decision-making and information dissemination. Clinicians were inspired by their patients and explained creative trade-offs and workarounds used to maintain high-quality care. CONCLUSIONS: Factors previously described as contributing to resilient health care manifested differently in each institution but were described in all resource settings. These insights can guide pediatric oncology teams worldwide as they provide cancer care during the next phases of the pandemic. Understanding these elements of resilience will also help providers respond to inevitable future stressors on health care systems.
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COVID-19 , Neoplasias , Criança , Atenção à Saúde , Humanos , Neoplasias/epidemiologia , Neoplasias/terapia , Pandemias , SARS-CoV-2RESUMO
BACKGROUND: The COVID-19 pandemic has exerted an unprecedented and universal impact on global health system, resulting in noticeable challenges in traditional chronic disease care, of which diabetes was reported to be most influenced by the reduction in healthcare resources in the pandemic. China has the world's largest diabetes population, and current diabetes management in China is unsatisfactory, particularly in rural areas. Studies in developed countries have demonstrated that physician-pharmacist collaborative clinics are efficient and cost-effective for diabetes management, but little is known if this mode could be adapted in primary hospitals in China. The aim of this proposed study is to develop and evaluate physician-pharmacist collaborative clinics to manage type 2 diabetes mellitus (T2DM) in primary hospitals in Hunan province. METHODS: A multi-site randomized controlled trial will be conducted to evaluate the effectiveness and cost-effectiveness of the physician-pharmacist collaborative clinics compared with usual care for Chinese patients with T2DM. Six primary hospitals will participate in the study, which will recruit 600 eligible patients. Patients in the intervention group will receive services from both physicians and pharmacists in the collaborative clinics, while the control group will receive usual care from physicians. Patients will be followed up at the 3rd, 6th, 9th and 12th month. Comparison between the two groups will be conducted by assessing the clinical parameters, process indicators and costs on diabetes. A satisfaction survey will also be carried out at the end of the study. DISCUSSION: If effective, the physician-pharmacist collaborative clinics can be adapted and used in primary hospitals of China to improve glycemic control, enhance medication adherence, decrease incidence of complications and reduce patients' dependence on physicians. Findings from the present study are meaningful for developing evidence-based diabetes care policy in rural China, especially in the COVID-19 pandemic era. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2000031839 , Registered 12 April 2020.
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COVID-19 , Diabetes Mellitus Tipo 2 , Relações Interprofissionais , Farmacêuticos , Médicos , COVID-19/epidemiologia , China/epidemiologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Hospitais , Humanos , Estudos Multicêntricos como Assunto , Pandemias , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
PURPOSE: To validate a simplified Chinese version of the therapy-related symptom checklist for children (TRSC-C) in children with cancer. METHODS: Reliability was assessed by internal consistency and test-retest coefficients. Dimensionality and construct validity were clarified using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Pearson's correlation coefficient was calculated between the TRSC-C and the PedsQL 3.0 cancer model (PedsQL 3.0) and the Lansky Play Performance Scale (LPPS) to test concurrent validity. A Student's t-test was used to compare the scores of the simplified Chinese version of the TRSC-C subscales by gender, age groups, and functional status to test sensitivity of the TRSC-C. RESULTS: A sample of 170 children with cancer was recruited (11.27 ± 2.31 years). Cronbach's alpha (0.89) and interclass correlation coefficient (0.98) were acceptable. Seven factors with eigenvalues >1 explained 56.86% of the total variances. CFA demonstrated an acceptable model (CFI = 0.93, RMSE = 0.04). Concurrent validity was supported by moderate to high correlations between the TRSC-C and both the PedsQL 3.0 (r = -0.71) and LPPS (r = -0.43). The TRSC-C scores significantly differed by age groups and functional status (effect size 0.40-0.93), indicating adequate sensitivity. CONCLUSION: The simplified Chinese version of the TRSC-C demonstrated acceptable reliability, validity, and sensitivity to support its use in clinical practice and future studies.
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Lista de Checagem , Neoplasias , Criança , China , Humanos , Neoplasias/diagnóstico , Neoplasias/terapia , Psicometria , Reprodutibilidade dos Testes , Inquéritos e QuestionáriosRESUMO
Food extract supplements, with high functional activity and low side effects, play a recognized role in the adjunctive therapy of human colorectal cancer. The present study reported a new functional beverage, which is a type of Chinese Hakka stir-fried green tea (HSGT) aged for several years. The extracts of the lyophilized powder of five HSGT samples with different aging periods were analyzed with high-performance liquid chromatography. The major components of the extract were found to include polyphenols, catechins, amino acids, catechins, gallic acid and caffeine. The tea extracts were also investigated for their therapeutic activity against human colorectal cancer cells, HT-29, an epithelial cell isolated from the primary tumor. The effect of different aging time of the tea on the anticancer potency was compared. Our results showed that, at the cellular level, all the extracts of the aged teas significantly inhibited the proliferation of HT-29 in a concentration-dependent manner. In particular, two samples prepared in 2015 (15Y, aged for 6 years) and 2019 (19Y, aged for 2 years) exhibited the highest inhibition rate for 48 h treatment (cell viability was 50% at 0.2 mg/mL). Further, all the aged tea extracts examined were able to enhance the apoptosis of HT-29 cells (apoptosis rate > 25%) and block the transition of G1/S phase (cell-cycle distribution (CSD) from <20% to >30%) population to G2/M phase (CSD from nearly 30% to nearly 10%) at 0.2 mg/mL for 24 h or 48 h. Western blotting results also showed that the tea extracts inhibited cyclin-dependent kinases 2/4 (CDK2, CDK4) and CylinB1 protein expression, as well as increased poly ADP-ribose polymerase (PRAP) expression and Bcl2-associated X (Bax)/B-cell lymphoma-2 (Bcl2) ratio. In addition, an upstream signal of one of the above proteins, phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signalling, was found to be involved in the regulation, as evidenced by the inhibition of phosphorylated PI3K and AKT by the extracts of the aged tea. Therefore, our study reveals that traditional Chinese aged tea (HSGT) may inhibit colon cancer cell proliferation, cell-cycle progression and promoted apoptosis of colon cancer cells by inactivating PI3K/AKT signalling.
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Camellia sinensis , Neoplasias do Colo , Neoplasias Colorretais , Humanos , Apoptose , Camellia sinensis/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Fosfatidilinositol 3-Quinase , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2 , Chá/químicaRESUMO
Crystalline block copolymers have been used to prepare plate-like colloidal systems with well-controlled size, shape, and size distribution. The isotropic-to-nematic (I-N) phase transition of the novel plate-like colloidal particle suspensions has been reported previously. In this work, we focus on the characterization of the solution structure of the crystals and the N-phase using small- and ultrasmall-angle X-ray scattering techniques (SAXS/USAXS). The system has polystyrene-block-poly(l-lactide) (PS-b-PLLA) block copolymer single crystals (BCSCs) with different sizes dispersed in p-xylene. These crystals are truncated lozenge in shape and have effective diameters ranging from 550 to 4000 nm with a uniform dry thickness of 18.0 nm. Scattering of the individual crystal in solution can be simplified using a disc model with a core layer of 9-10 nm due to the lower contrast of the tethered PS layer. BCSC suspensions filled in thin quartz capillaries are prepared for monitoring the structural information. SAXS measurements of the isotropic phase show a strong face-to-face correlation, indicating that platelets form small stacked clusters in solutions. The isotropic phase is thus a coexistence of single crystals and the stacked multiple-layered clusters. The face-to-face spacing, d, in the N phases is around 75-90 nm, which increases slightly upon increasing the size of crystals. For a given system, the spacing does not change with increasing concentration under the current experimental conditions. Finally, the possible formation of lamellar domains within the N phase is also discussed due to the lateral attraction of this system. These results demonstrate the importance of the lateral attraction between the polar crystalline PLLA blocks on the formation of the N phase: the BCSCs self-assemble into larger sheets via the lateral attraction, which further enhances the I-N transition.
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PURPOSE: Cancer survivorship starts at diagnosis. Transition readiness is an important indicator for pediatric cancer survivors to move from pediatric to adult medical care. Appropriate measurement of transition readiness can facilitate better cancer survivorship. This study aimed to translate and validate of the English version of the TRANSITION-Q into Chinese. DESIGN AND METHODS: The translation followed the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) best-practice guidelines for the translation and cultural adaptation of patient-reported outcome measures (PROM). A cross- psychometric testing on reliability and validity were conducted from a convenient sample of Chinese adolescent cancer survivors aged 10-19 years. RESULTS: Two hundred seventy-one pediatric cancer patients were recruited for the psychometric validation. The 14-item Chinese TRANSITION-Q demonstrated adequate reliability. In exploratory factorial analyses and confirmatory factor analysis, a two-factor structure emerged with a variance of 54.78%, demonstrating construct validity. Convergent validity test showed TRANSITION-Q score was significantly positively correlated with self-efficacy (r = -0.84, p = 0.002). The known-group validity demonstrated the older group (age ≥14 years) had a significantly higher mean TRANSITION-Q score than the younger group (age < 14 years) (p = 0.04). CONCLUSION: The Chinese version of the TRANSITION-Q is reliable and valid and can be used in Chinese research and clinical settings. IMPLICATIONS FOR PRACTICE: This scale can be used in Chinese clinical and research settings to investigate understanding of transition readiness in Chinese pediatric cancer survivors.
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Sobreviventes de Câncer , Neoplasias , Transição para Assistência do Adulto , Adolescente , Adulto , Criança , China , Humanos , Neoplasias/diagnóstico , Neoplasias/terapia , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários , TraduçõesRESUMO
A drug delivery system of forsythoside A-loaded exosomes(FTA-Exos) with high biocompatibility and low immunogenicity was established to investigate its impact on the migration of human lung epithelial adenocarcinoma A549 cells. The exosomes from A549 cells were extracted and purified by ultra-high speed centrifugation and ultrafiltration. FTA-Exos were prepared by ultrasonic incubation, and characterized by particle size analysis, transmission electron microscopy, and Western blot assay. The uptake of FTA-Exos by A549 cells was observed under the laser confocal microscope, and the impact of FTA-Exos on the migration of A549 cells was investigated by cell scratch assay. The results showed that the average particle size of the prepared FTA-Exos was(138.90±2.37) nm, which increased slightly after drug loading. The PDI was 0.291±0.013, and the average potential was(-10.1±0.66) mV. The FTA-Exos were spheroidal in appearance as observed by transmission electron microscope, with an obvious saucer-like double-layer membrane. Western blot assay indicated that the specific proteins CD63 and Alix were both expressed in exosomes. The laser confocal microscopy suggested that FTA-Exos were taken up by A549 cells and stably maintained in the cell for 4-8 h, and the fluorescence was significantly enhanced at 4 h. The scratch assay showed that the inhibitory effect of FTA-Exos on the migration of A549 cells was significantly stronger than that of forsythoside A(P < 0.05). In conclusion, the drug delivery system of FTA-Exos established in this study had good stability, reliable preparation process, and potent inhibitory effect on the migration of A549 cells in vitro, which can provide an important reference for subsequent in-depth research and application.
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Exossomos , Glicosídeos , HumanosRESUMO
Chronic obstructive pulmonary disease (COPD) is a leading cause of death due to tis high morbidity and mortality. microRNAs have emerged as new biomarkers for the prognosis and diagnosis of patients with COPD. In this study, we aimed to investigate the expression of microRNA-206 (miR-206) in lung tissues from COPD patients and to explore the regulatory role of miR-206 in the human pulmonary microvascular endothelial cells (HPMECs). Our results showed that cigarette smoke extract (CSE) promoted cell apoptosis, increased caspase-3 activity, and upregulated the expression of miR-206 in HPMECs, which was significantly reversed by the miR-206 knockdown. Transfection with miR-206 mimics led to cell apoptosis and was closely related to changes in the protein expression levels of caspase-3, caspase-9, and Bcl-2 in HPMECs. Further bioinformatics prediction analysis revealed that the 3'-untranslated region (3'UTR) of Notch3 and vascular endothelial growth factor-A (VEGFA) harbored miR-206-binding sites, and overexpression of miR-206 repressed the luciferase activity of the vectors containing Notch3 and VEGFA 3'UTR. Overexpression of either Notch3 or VEGFA attenuated miR-206-induced cell apoptosis in HPMECs. More importantly, miR-206 expression was upregulated in the lung tissues from COPD patients and was positively corrected with forced expiratory volume 1% predicted in COPD patients, while Notch3 and VEGFA mRNA levels were downregulated and were negatively correlated with the expression level of miR-206 in the lung tissues from COPD patients. In conclusion, our results showed that miR-206 was upregulated in COPD patients and CSE-treated HPMECs, promoted cell apoptosis via directly targeting Notch3 and VEGFA in HPMECs.
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MicroRNAs/genética , Doença Pulmonar Obstrutiva Crônica/genética , Receptor Notch3/genética , Fumaça/efeitos adversos , Fator A de Crescimento do Endotélio Vascular/genética , Regiões 3' não Traduzidas , Idoso , Estudos de Casos e Controles , Caspase 3/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Receptor Notch3/metabolismo , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
AIMS: To examine the effects of a group-based physical activity intervention on improvement in physical activity and mitigation of symptom distress among pediatric patients with cancer. METHODS: Based on convenience sampling, 57 pediatric patients with cancer admitted to the cancer center were included in the intervention group. The control group included 57 pediatric patients with cancer from two other hospitals matched to the patients in the intervention group by age, sex, and diagnosis. A group-based physical activity program was implemented among the children in the intervention group, whereas the children in the control group received standard care. Physical activity and symptoms were measured using the Children's Leisure Time Activities Study Survey-Chinese and using the Memorial Symptom Assessment Scale 10-18 at baseline and after the 12th exercise session in both the intervention and control groups. RESULTS: The repeated-measures analysis of variance showed that the main intervention effects on the decrease in light-intensity physical activity and increase in moderate-to-vigorous physical activity were significant between the two groups (P < .001). The group-based physical activity intervention could decrease the scores of psychological symptoms (P < .001), Global Distress Index (P < .001), and physical symptoms (P = .01) when comparing the difference between the two groups before and after the intervention. There was no significant difference in the number of symptoms or the total symptom experience score between the two groups. CONCLUSION: These findings suggest that a group-based physical activity intervention can promote physical activity and relieve psychological and physical symptom distress among pediatric patients with cancer.
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Exercício Físico , Neoplasias/reabilitação , Modalidades de Fisioterapia , Ludoterapia , Qualidade de Vida , Adolescente , Criança , Pré-Escolar , Feminino , Hong Kong , Humanos , Masculino , Exercícios de Alongamento Muscular , Neoplasias/psicologia , Educação de Pacientes como Assunto , Pacientes/psicologia , Treinamento Resistido , Esportes , Avaliação de Sintomas , Resultado do Tratamento , CaminhadaRESUMO
The sequential layer by layer self-assembly of block copolymer (BCP) nanopatterns is an effective approach to construct 3D nanostructures. Here large-scale highly ordered metal nano-arrays prepared from solvent annealed thin films of polystyrene-block-poly(2-vinylpyridine) (PS-b-P2VP) diblock copolymer are used to direct the assembly of the same BCP. The influence of initial loading concentration of metal precursor, the type of metal nanoparticle (gold, platinum, and silver), and the nanoparticle-substrate interaction on the directed assembly behavior of the upper BCP layer have been focused. It is found that the upper BCP film can be completely directed by the gold nanoarray with P2VP domain exclusively located between two adjacent gold nanowires or nanodots, which behaves the same way as on the platinum nanoarray. While the silver nanoarray can be destroyed during the upper BCP self-assembly with the silver nanoparticles assembled into the P2VP domain. Based on the discussions of the surface energy of nanoparticles and the interplay between nanoparticle-substrate interaction and nanoparticle-polymer interaction, it is concluded that the effect of immobilization of nanoparticles on the substrate, together with entropy effect to minimize the energetically unfavorable chain stretching contributes to the most effective alignment between each layer.
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Nanopartículas Metálicas/química , Nanofios/química , Poliestirenos/química , Polivinil/química , Ouro/química , Nanopartículas Metálicas/ultraestrutura , Micelas , Nanofios/ultraestrutura , Tamanho da Partícula , Platina/química , Prata/química , Propriedades de Superfície , TermodinâmicaRESUMO
Strain LZ-C, isolated from a petrochemical wastewater discharge site, was found to be resistant to heavy metals and to degrade various aromatic compounds, including naphenol, naphthalene, 2-methylnaphthalene and toluene. Data obtained from 16S rRNA gene sequencing showed that this strain was closely related to Delftia lacustris. The 5,889,360 bp genome of strain LZ-C was assembled into 239 contigs and 197 scaffolds containing 5855 predicted open reading frames (ORFs). Among these predicted ORFs, 464 were different from the type strain of Delftia. The minimal inhibitory concentrations were 4 mM, 30 µM, 2 mM and 1 mM for Cr(VI), Hg(II), Cd(II) and Pb(II), respectively. Both genome sequencing and quantitative real-time PCR data revealed that genes related to Chr, Czc and Mer family genes play important roles in heavy metal resistance in strain LZ-C. In addition, the Na(+)/H(+) antiporter NhaA is important for adaptation to high salinity resistance (2.5 M NaCl). The complete pathways of benzene and benzoate degradation were identified through KEGG analysis. Interestingly, strain LZ-C also degrades naphthalene but lacks the key naphthalene degradation gene NahA. Thus, we propose that strain LZ-C exhibits a novel protein with a function similar to NahA. This study is the first to reveal the mechanisms of heavy metal resistance and salinity tolerance in D. lacustris and to identify a potential 2-methylnaphthalene degradation protein in this strain. Through whole-genome sequencing analysis, strain LZ-C might be a good candidate for the bioremediation of heavy metals and polycyclic aromatic hydrocarbons.
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Delftia/genética , Delftia/metabolismo , Genoma Bacteriano , Metais Pesados/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes do Solo/metabolismo , China , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNARESUMO
In this paper 200 girls with precocious puberty or advanced puberty were clinically sur- veyed, and the literatures of traditional Chinese medicine (TCM) for treating precocious puberty in previ- ous 33 years were retrospectively analyzed. By conjecturing syndromes from symptoms and identifying syndrome types from efficacies of TCM drugs, authors proved that Gan yin deficiency syndrome occupies the same important position as Shen yin deficiency syndrome, or even more important position in syn- drome based treatment of precocious puberty children patients with yin deficiency caused fire hyperactivity syndrome. Therefore, Gan yin deficiency syndrome cannot be neglected in treating precocious puberty pa- tients. Authors further suggested that yin deficiency caused fire hyperactivity syndrome in precocious pu- berty should be exactly described as Gan-Shen yin deficiency caused fire hyperactivity syndrome.
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Medicina Tradicional Chinesa , Puberdade Precoce , Deficiência da Energia Yin , Criança , Feminino , Humanos , Estudos Retrospectivos , Síndrome , Deficiência da Energia YangRESUMO
BACKGROUND: Oroxylin A, a natural flavonoid isolated from Scutellariae baicalensis, has been reported to possess a wide spectrum of pharmacologic activities. However, the effects of oroxylin A on liver injury are poor understood. The purpose of this study was to investigate the effects of oroxylin A on acute liver injury in mice induced by lipopolysaccharide and/or D-galactosamine (LPS and/or D-GalN). METHODS: Mice acute liver injury model was induced by LPS (50 µg/kg) and/or GalN (800 mg/kg). Serum alanine aminotransferase, aspartate aminotransferase, and tumor necrosis factor-α levels, hepatic tissue histology, malondialdehyde content, and myeloperoxidase activity were analyzed. Meanwhile, nuclear factor kappa B (NF-κB), heme oxygenase-1 (HO-1), and nuclear factor erythroid2-related factor 2 (Nrf2) expression were detected by Western blotting. RESULTS: The results showed that oroxylin A dose-dependently inhibited LPS and/or GalN-induced serum alanine aminotransferase, aspartate aminotransferase, and tumor necrosis factor-α levels. Hepatic malondialdehyde content and myeloperoxidase activity were also suppressed by oroxylin A. We also found that oroxylin A inhibited LPS and/or GalN-induced toll like receptor 4 (TLR4) expression and NF-κB activation. In addition, oroxylin A upregulated the expression of Nrf2 and HO-1 in a dose-dependent manner. CONCLUSIONS: In conclusion, oroxylin A protected against LPS and/or GalN-induced liver injury through activating Nrf2 and inhibiting TLR4 signaling pathway.
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Flavonoides/uso terapêutico , Falência Hepática Aguda/prevenção & controle , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Flavonoides/farmacologia , Galactosamina/toxicidade , Lipopolissacarídeos/toxicidade , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Camundongos Endogâmicos BALB C , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Peroxidase/metabolismo , Receptor 4 Toll-Like/fisiologia , Fator de Necrose Tumoral alfa/biossínteseRESUMO
Nanotubes have attracted considerable attention due to their unique 1D hollow structure; however, the fabrication of pure nanotubes via block copolymer self-assembly remains a challenge. In this work, the successful preparation of core-shell-corona (CSC) nanotubular micelles with uniform diameter and high aspect ratio is reported, which is achieved via self-assembly of a poly (styrene-b-4-vinyl pyridine-b-ethylene oxide) triblock terpolymer in binary organic solvents with assistance of solution thermal annealing. Via direct visualization of trapped intermediates, the nanotube is believed to be formed via large sphere-large solid cylinderical aggregates-nanotube transformations, wherein the unique solid to hollow transition accompanied with the unidirectional growth is distinct from conventional pathway. In addition, by virtue of the CSC structure, gold nanoparticles are able to be selectively incorporated into different micellar domains of the nanotubes, which may have potential applications in nanoscience and nanotechnology.
Assuntos
Nanotubos/química , Polietilenoglicóis/química , Polímeros/química , Poliestirenos/química , Polivinil/química , Ouro/química , Nanopartículas Metálicas/química , Micelas , Microscopia de Força Atômica , Nanotubos/ultraestrutura , TemperaturaRESUMO
In this work, micelles are formed by gradient copolymer of styrene and methyl methacrylate in acetone-water mixture and their temperature responsiveness is investigated in a narrow range near room temperature. Three different kinds of structural transitions could be induced by temperature: unimers to micelle transition, shrinkage/stretching of micelles, and morphological transition from spherical micelles to vesicles. In addition, a model analysis on the interface of gradient copolymer micelle is made to better understand these phenomena. It is found that both position and composition of the interface could alter in response to the change in temperature. According to the experiments and model analysis, it is proposed that temperature responsiveness might be an intrinsic and universal property of gradient copolymer micelles, which only originates from the gradient structure.