RESUMO
This paper examines a new study on the synergistic effect of magnetic nanoparticles and wormlike micelles (WLMs) on drag reduction. Fe3O4 magnetic nanoparticles (FE-NPs) are utilized to improve the performance of viscoelastic surfactant (VES) solutions used as fracturing fluids. The chemical composition and micromorphology of the FE-NPs were analyzed with FT-IR and an electron microscope. The stability and interaction of the WLM-particle system were studied by zeta potential and cryo-TEM measurements. More importantly, the influences of the temperature, FE-NP concentration, magnetic field intensity, and direction on the drag reduction rate of WLMs were systematically investigated in a circuit pipe flow system with an electromagnetic unit. The experimental results show that a suitable content of magnetic nanoparticles can enhance the settlement stability and temperature resistance of WLMs. A magnetic field along the flow direction of the fracturing fluid can improve the drag reduction performance of the magnetic WLM system. However, under a magnetic field perpendicular to the direction of fluid flow, an additional flow resistance is generated by the vertical chaining behavior of FE-NPs, which is unfavorable for the drag reduction performance of magnetic VES fracturing fluids. This study may shed light on the mechanism of the synergistic drag reduction effects of magnetic nanoparticles and wormlike micelles.
RESUMO
BACKGROUND: Tube dislodgment has been ranked as the top three medical accidents for five years consecutively in Taiwan. Chest tube care accidents affect patient's health and life significantly. Typically, education on chest tube care focuses on the knowledge transmission with limited guiding nursing students in learning clinical reasoning. The Generation Z students prefer mobile devices. It is crucial to incorporate mobile applications to learning. PURPOSE: The purpose of this study was to evaluate effectiveness of the teaching intervention program ("iLearning app for chest tube care") in improving nursing students' clinical reasoning ability and self-directed learning. METHOD: A quasi-experimental study with a cluster sample was used. A total of 107 nursing students were recruited with the intervention group (n = 53) using the "iLearning app" to learn chest tube care, and the comparison group (n = 54) using the "traditional teaching". Data were collected before the intervention, one week and one month after the intervention. RESULT: The result showed that there was no difference in clinical reasoning and self-directed learning between groups before the intervention. However, the intervention group showed significantly higher clinical reasoning and self-directed learning scores than the comparison group (p < .05) one week and one month after the intervention. It indicated that the students' clinical reasoning abilities and self-directed learning improved with implementation of the intervention. CONCLUSION: The results indicated that the "iLearning app" intervention improved the clinical reasoning and self-directed learning in nursing students. This intervention used situated learning with concept mapping to guide student learning and demonstrated effectiveness in improving their clinical reasoning ability. Immediate feedback of the course instructor might trigger deeper learning and self-correction of clinical reasoning. The "iLearning app" could be used as a tool to improve students' clinical reasoning and self-directed learning, and thus enhance lifelong learning.
Assuntos
Tubos Torácicos , Bacharelado em Enfermagem , Estudantes de Enfermagem , Competência Clínica , Humanos , TaiwanRESUMO
Portable/Implantable biomedical applications usually exhibit stringent power budgets for prolonging battery life time, but loose operating frequency requirements due to small bio-signal bandwidths, typically below a few kHz. The use of sub-threshold digital circuits is ideal in such scenario to achieve optimized power/speed tradeoffs. This paper discusses the design of a sub-threshold standard cell library using a standard 0.18-µm CMOS technology. A complete library of 56 standard cells is designed and the methodology is ensured through schematic design, transistor width scaling and layout design, as well as timing, power and functionality characterization. Performance comparison between our sub-threshold standard cell library and a commercial standard cell library using a 5-stage ring oscillator and an ECG designated FIR filter is performed. Simulation results show that our library achieves a total power saving of 95.62% and a leakage power reduction of 97.54% when compared with the same design implemented by the commercial standard cell library (SCL).
Assuntos
Fontes de Energia Elétrica , Desenho de Equipamento , Processamento de Sinais Assistido por Computador/instrumentação , Simulação por Computador , Eletricidade , Humanos , Próteses e Implantes , Software , Tecnologia sem FioRESUMO
The aim of the current study was to determine the feasibility, efficacy and safety of ovarian castration by high-intensity focused ultrasound (HIFU) in premenopausal patients with estrogen receptor (ER)(+)/progesterone receptor (PR)(+) breast cancer subsequent to radical mastectomy. A total of 88 premenopausal females with pathologically confirmed ER(+)/PR(+) breast cancer following radical mastectomy were randomly and equally divided into two groups that received HIFU therapy or radiation treatment. HIFU therapy was applied twice at an interval of three days and radiotherapy was administered to a total prescribed dose of D(T) 18 Gy in nine fractions over 11 days. Outcome measures included serum levels of estradiol and estrone, the Kupperman index and the incidence of secondary amenorrhea. Adverse events were monitored and recorded. All patients were followed up for 12 months. Serum levels of estradiol and estrone were comparable prior to treatment between the HIFU and radiation treatment groups. One month following treatment, serum levels of estradiol and estrone were significantly decreased in the two groups, but a greater decline was observed in the HIFU treatment group (P<0.01 and 0.05, respectively). In addition, more patients developed severe menopausal symptoms and amenorrhea in the HIFU therapy group compared with the radiotherapy group (P<0.01 for the two groups). A total of 3 months following treatment, serum levels of estradiol and estrone and the distribution of patients with severe, moderate and mild menopausal symptoms were comparable between the two groups. Following nine menstrual cycles, the incidence of amenorrhea reached 100% in the two groups. HIFU therapy is superior to radiotherapy for ovarian castration in premenopausal females with ER(+)/PR(+) breast cancer subsequent to radical mastectomy in terms of its minimal invasiveness and faster efficacy. HIFU represents a feasible non-surgical approach for ovarian castration.
RESUMO
We reported previously that regenerated Antheraea pernyi silk fibroin (A. pernyi SF) could support the attachment and growth of human bone marrow mesenchymal stem cells (hBMSCs). In this work, the immunosupressive effects of hBMSCs cultured on the A. pernyi SF films on T-cells were investigated in vitro. The production of IL-6, CD80, CD86 and HLA-DR by the hBMSCs was also observed. The study showed that hBMSCs cultured on the regenerated A. pernyi SF films still kept their immunosupression on T-cell proliferation and IL-2 secretion. Moreover, regenerated A. pernyi SF like regenerated Bombyx mori SF and collagen did not elicit T-cell proliferation but it could support the expression of IL-6 and surface antigen of hBMSCs. Regenerated A. pernyi SF can maintain the function of hBMSCs in immunomodulation and cytokines production, which has the potential utility of hBMSCs combined with A. pernyi SF in tissue replacement and repair.
Assuntos
Células da Medula Óssea/imunologia , Fibroínas , Tolerância Imunológica/efeitos dos fármacos , Tolerância Imunológica/imunologia , Terapia de Imunossupressão , Células-Tronco Mesenquimais/imunologia , Animais , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Células da Medula Óssea/metabolismo , Proliferação de Células , Antígenos HLA-DR/metabolismo , Humanos , Interleucina-2/metabolismo , Interleucina-6/metabolismo , Ativação Linfocitária/imunologia , Teste de Materiais , Membranas Artificiais , Células-Tronco Mesenquimais/metabolismo , Mariposas , Linfócitos T/imunologia , Linfócitos T/metabolismoRESUMO
OBJECTIVE: To investigate the efficacy, safety and the life quality improvement of uroacitides injection in the treatment for patients with advanced malignant tumors. METHODS: A total of 160 patients with advanced stage cancers were enrolled into this multicenter, open and non-randomized phase II clinical trial, including cancers of the lung (33 cases), liver (45 cases), breast (17 cases), esophagus (11 cases), stomach (18 cases), colon (19 cases), pancreas (3 cases) and kidney (4 cases), and glioma (10 cases). Uroacitides was administrated in a dose of 300 ml daily via the superior vena cava catheter for consecutive 4-8 weeks. RESULTS: Of the 160 patients, 21 dropped out and one patient died during the trial. Efficacy could be evaluated in 138 patients and safety in 160. The total objective response rate (ORR, CR + PR)) and tumor control rate (CR + PR + MR + SD) of the 138 evaluable patients were 5.8% and 65.2%, respectively. Clinical benefit response (CBR) rate was 57.2%. Major adverse effects were grade I - II and reversible nausea/vomiting (21.9%) and pain (6.3%). CONCLUSION: Uroacitides injection is effective in the control for various kinds of advanced cancers with mild, reversible and tolerable adverse effects, and can also improve the patient's quality of life. It is worth being studied further.
Assuntos
Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Metiltransferases/uso terapêutico , Peptídeos/uso terapêutico , Fenilacetatos/uso terapêutico , Neoplasias da Mama/sangue , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Antígeno CA-19-9/sangue , Antígeno Carcinoembrionário/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Cateterismo Venoso Central , Neoplasias Colorretais/sangue , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/patologia , Metiltransferases/administração & dosagem , Metiltransferases/efeitos adversos , Metiltransferases/antagonistas & inibidores , Náusea/induzido quimicamente , Estadiamento de Neoplasias , Peptídeos/administração & dosagem , Peptídeos/efeitos adversos , Fenilacetatos/administração & dosagem , Fenilacetatos/efeitos adversos , Qualidade de Vida , Indução de Remissão , Terapia de Salvação , Resultado do Tratamento , Vômito/induzido quimicamente , alfa-Fetoproteínas/metabolismoRESUMO
This study is to investigate the effect of curcumin on the induction of glutathione S-transferases (GST) and NADP(H):quinone oxidoreductase (NQO) and explore their possible molecular mechanism. The activity of GST, NQO and cellular reduced glutathione (GSH) content were measured by spectrophotometrical methods. Cellular changes in the distribution of NF-E2 related factor 2 (Nrf2) were detected by Western blotting analysis. Nrf2-AREs (antioxidant-responsive elements) binding activity was examined by electrophoretic mobility shift assay (EMSA). Treatment of HT-29 human colon adenocarcinoma cells with curcumin dramatically induced the activity of GST and NQO at the range of 10-30 micromol x L(-1). Curcumin exposure caused a significant increase in cellular GSH content rapidly as early as 3 h. Moreover, curcumin triggered the accumulation of Nrf2 in nucleus, and increased Nrf2 content in ARE complexes. These results demonstrated that induction of GST and NQO activity by curcumin may be mediated by translocation of transcription factor Nrf2 from cytoplasm to nuclear and increased binding activity of Nrf2-ARE complexes.
Assuntos
Humanos , Antineoplásicos , Farmacologia , Antioxidantes , Metabolismo , Núcleo Celular , Metabolismo , Curcumina , Farmacologia , Indução Enzimática , Glutationa , Metabolismo , Glutationa Transferase , Metabolismo , Células HT29 , NAD(P)H Desidrogenase (Quinona) , Metabolismo , Fator 2 Relacionado a NF-E2 , Metabolismo , Elementos de Resposta , Transdução de SinaisRESUMO
Silk fibroin of the silkworm Bombyx mori has been studied extensively, while the research on Antheraea pernyi silk fibroin (A. pernyi SF) in biomaterials is only at an early stage. In this study, the attachment, morphology, growth and phenotype of human bone marrow derived mesenchymal stem cells (hBMSCs) cultured on the regenerated A. pernyi SF films were studied in vitro. The results indicated that the attachment of hBMSCs on the regenerated A. pernyi SF films was almost the same as that on the collagen films. MTT and cell counting analyses demonstrated that the growth of hBMSCs on the regenerated A. pernyi SF films was better than that on controls. Moreover, electron scanning microscopy and fluorescence-activated cell sorting assays showed that the regenerated A. pernyi SF supported hBMSCs growth and functional maintenance compared with the controls. These data suggest that the regenerated A. pernyi SF, like Bombyx mori silk fibroin (B. mori SF) and collagen, can support hBMSCs attachment, growth and phenotypic maintenance, and has better biocompatibilities for hBMSCs in vitro culture.
Assuntos
Células da Medula Óssea/citologia , Células da Medula Óssea/fisiologia , Técnicas de Cultura de Células/métodos , Fibroínas/química , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Mariposas/metabolismo , Seda/química , Engenharia Tecidual/métodos , Animais , Adesão Celular/fisiologia , Proliferação de Células , Células Cultivadas , Teste de Materiais , Membranas ArtificiaisRESUMO
AIM: A study was performed to investigate the impact of comorbid anxiety and depression (CAD) on quality of life (QOL) and cellular immunity changes in patients with digestive tract cancers. METHODS: One hundred and fifty-six cases of both sexes with cancers of the digestive tract admitted between March 2001 and February 2004 in the Department of Medical Oncology, First Affiliated Hospital of Xi'an Jiaotong University were randomly enrolled in the study. Depressive and anxiety disorder diagnoses were assessed by using the Structured Clinical Interview for DSM-IV. All adult patients were evaluated with the Hamilton depressive scale (HAMD, the 24-item version), the Hamilton anxiety scale (HAMA, a modified 14-item version), quality of life questionnaire-core 30 (QLQ-C30), social support rating scale (SSRS), simple coping style questionnaire (SCSQ), and other questionnaires, respectively. In terms of HAMD > or = 20 and HAMA > or = 14, the patients were categorized, including CAD (n = 31) in group A, anxiety disorder (n = 23) in group B, depressive disorder (n = 37) in group C, and non-disorder (n = 65) in group D. Immunological parameters such as T-lymphocyte subsets and natural killer (NK) cell activities in peripheral blood were determined and compared among the four groups. RESULTS: The incidence of CAD was 21.15% in patients with digestive tract cancers. The average scores of social support was 43.67+/-7.05 for 156 cases, active coping 20.34+/-7.33, and passive coping 9.55+/-5.51. Compared with group D, subjective support was enhanced slightly in group A, but social support, objective support, and utilization of support reduced, especially utilization of support with significance (6.16 vs 7.80, P<0.05); total scores of active coping decreased, while passive coping reversed; granulocytes proliferated, monocytes declined, and lymphocytes declined significantly (32.87 vs 34.00, P<0.05); moreover, the percentage of CD3, CD4, CD8 and CD56 in T lymphocyte subsets was in lower level, respectively, and CD56 showed a significant decline in group A (26.02 vs 32.20, P<0.05), however, CD4/CD8 ratio increased. Physical function, role function, fatigue, sleeplessness and constipation had significant changes among different groups by one-way ANOVA, and group A was in poor QOL. It revealed that global health-related quality of life (QL) were positively correlated with active coping and CD56; CAD was negatively correlated with QL, active coping and CD56. Furthermore, the step-wise regression analysis suggested that utilization of support, CD56, active coping, fatigue, sleeplessness and depression were significant factors contributing to QOL. CONCLUSION: CAD, which can impair QOL and cellular immunity, occurs with a higher incidence in patients with digestive tract cancers. Hence, it is essential to improve mental health for them with specifically tailored interventions.
Assuntos
Ansiedade/imunologia , Depressão/imunologia , Neoplasias do Sistema Digestório/imunologia , Neoplasias do Sistema Digestório/psicologia , Qualidade de Vida , Idoso , Ansiedade/epidemiologia , Ansiedade/psicologia , Comorbidade , Depressão/epidemiologia , Depressão/psicologia , Neoplasias do Sistema Digestório/epidemiologia , Feminino , Humanos , Incidência , Células Matadoras Naturais/imunologia , Masculino , Pessoa de Meia-Idade , Apoio Social , Linfócitos T/imunologiaRESUMO
Objective To explore a more reasonable and effective therapeutic regimen and evaluate prognostic factors in hepatoblastoma patients after combined therapy.Methods Sixteen patients diagnosed on hepatoblastoma between Jan.2000 and Nov.2007 were reviewed and followed-up.Resection with chemotherapy was taken among 16 cases.Chemotherapy included pre-operation and post-operation.Five cases were cured by transcatheter arterial chemombolization(TACE).Six cases were cured by single chemotherapy(both TACE and single chemotherapy were taken in 2 cases).Five cases weren't cured by pre-operation chemotherapy.Nine cases were subjected to curative resection,3 cases to alleviative resection,2 cases with single chemotherapy,1 case with single TACE,and 1 case refused operation and left hospital.Their mean survival duration was 13.5 months(3-98 months).SPSS 13.0 software was used to analyze the data.Results The total survival rate of cases as stage Ⅳ as lower than cases as stage Ⅰ,Ⅱand Ⅲ.Both alpha-fetoprotein(AFP)100 000 ?g/L cases had worse survival rate.The prognosis of mixed type was better than fetal type,embryonal type and anaplasia type.The survival rate of cases with standard chemotherapy was higher than cases with unstandard chemotherapy.And the surgical resection cases had better survival chance than non-surgical resection cases.The survival rate of surgical residual cases was worse than non-surgical residual cases.Conclusions Chemotherapy can improve the total survival rate and long-term survival rate of hepatoblastoma patients.TACE is a safe and effective choice for hepatoblastoma patients.We need to be alert and make the diagnosis as early as possibe,and treat it early and properly.