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1.
J Clin Med ; 12(24)2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38137759

RESUMO

The adoption of neoadjuvant concurrent chemoradiotherapy (CCRT) has reshaped the therapeutic landscape, but response prediction remains challenging. This study investigates the interaction between pre-CCRT carcinoembryonic antigen (CEA) and post-CCRT hemoglobin (Hb) levels in predicting the response of locally advanced rectal cancer (LARC) to CCRT. Retrospective data from 93 rectal cancer patients receiving neoadjuvant CCRT were analyzed. Univariate analyses assessed clinical factors associated with tumor regression grade (TRG) and T-stage outcomes. Machine learning identified predictive biomarkers. Interaction effects between CEA and Hb were explored through subgroup analyses. Post-CCRT Hb varied between pre-CCRT CEA groups. The interaction between pre-CCRT CEA and post-CCRT Hb influenced TRG. Males with normal pre-CCRT CEA and anemia showed better treatment responses. Females with elevated pre-CCRT CEA and post-CCRT anemia exhibited poorer responses. The interaction effect between them was significant, indicating that their relationship with TRG was not additive. Inflammatory biomarkers, WBC, neutrophil count, and post-CCRT platelet level correlated with CCRT response. Contrasting with previous findings, anemia was a predictor of better treatment response in males with normal pre-CCRT CEA. The interaction between pre-CCRT CEA and post-CCRT Hb levels predicts the response of LARC to CCRT. CEA, Hb, and sex should be considered when assessing treatment response. Inflammatory biomarkers contribute to response prediction. Understanding these complex relationships can enhance personalized treatment approaches in rectal cancer patients.

2.
Environ Monit Assess ; 195(12): 1485, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37971611

RESUMO

Urban populations are exposed to a multitude of traffic-related air pollutants during daily commutes. This study assessed commuters' exposure to volatile organic compounds (VOCs) during bus, motorcycle, and bicycle commuting, and estimated the VOC inhalation dose. Benzene, toluene, ethylbenzene, and xylene (BTEX) were the main compounds detected, contributing 58 - 68% to ΣVOC (sum of the concentrations of all detected VOCs) in different travel modes. The mean ΣVOC exposure concentration was higher for motorcyclists than for cyclists and bus commuters. However, due to cyclists' higher minute ventilation rates and longer exposure time, they had the highest ΣVOC inhalation dose based on both travel time (7.09 ± 2.36 µg min-1) and distance (32.9 ± 10.8 µg km-1). Among the three travel modes, bus commuters had the lowest ΣVOC inhalation dose based on travel time (2.33 ± 1.18 µg min-1) and distance (8.91 ± 4.91 µg km-1), while motorcyclists had a moderate ΣVOC inhalation dose based on travel time (5.08 ± 1.46 µg min-1) and distance (13.4 ± 5.5 µg km-1). Health impact assessment of VOCs showed that cyclists faced the highest carcinogenic and non-carcinogenic risks, while bus commuters experienced the lowest health risk associated with VOC exposure. Our findings underscore the need to consider air quality in transportation infrastructure design and prioritize interventions to safeguard urban commuters' health, particularly cyclists, who are the most vulnerable to the adverse effects of traffic-related air pollutants.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Compostos Orgânicos Voláteis , Monitoramento Ambiental , Meios de Transporte , Emissões de Veículos/análise , Poluentes Atmosféricos/análise , Exposição Ambiental/análise
3.
J Microbiol Immunol Infect ; 56(6): 1207-1213, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37696685

RESUMO

BACKGROUND: Coronavirus disease-2019 (COVID-19) remains a global public health concern, and remdesivir plus dexamethasone combination therapy is suggested for patients with severe disease. However, the factors associated with poor outcomes in these patients remain unclear. We identified the factors associated with poor outcomes in Taiwanese patients with severe COVID-19 treated with remdesivir plus dexamethasone. METHODS: Adults with severe COVID-19 (oxygen saturation <94% on room air or requiring supplemental oxygen) treated with remdesivir and dexamethasone were identified between 1 May and 31 July 2021. The main outcomes were 14-day non-recovery, 28-day mortality, and progression to respiratory failure requiring invasive mechanical ventilation or death in initially non-ventilated patients. The prognostic factors associated with poor outcomes were analyzed by multivariate logistic regression and Cox regression. RESULTS: Of the 110 patients treated with remdesivir and dexamethasone, 57 (51.8%) recovered within 14 days and 6 (5.5%) died within 28 days. Of the 89 initially non-ventilated patients, 12 (13.5%) progressed to respiratory failure or death. Charlson Comorbidity Index, SOFA score, and admission to remdesivir treatment interval were associated with 14-day non-recovery. C-reactive protein level was associated with 28-day mortality. Pneumonia Severity Index and admission to remdesivir treatment interval were associated with progression to respiratory failure requiring invasive mechanical ventilation or death in initially non-ventilated patients. CONCLUSION: High disease severity on admission and delayed initiation of remdesivir therapy were associated with poor outcomes in COVID-19 patients treated with remdesivir and dexamethasone.


Assuntos
COVID-19 , Insuficiência Respiratória , Adulto , Humanos , SARS-CoV-2 , Taiwan , Prognóstico , Antivirais , Tratamento Farmacológico da COVID-19 , Dexametasona/uso terapêutico , Insuficiência Respiratória/tratamento farmacológico
4.
Int J Mol Sci ; 24(18)2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37762330

RESUMO

Interleukin (IL)-8 plays a vital role in regulating inflammation and breast cancer formation by activating CXCR1/2. We previously designed an antagonist peptide, (RF16), to inhibits the activation of downstream signaling pathways by competing with IL-8 in binding to CXCR1/2, thereby inhibiting IL-8-induced chemoattractant monocyte binding. To evaluate the effect of the RF16 peptide on breast cancer progression, triple-negative MDA-MB-231 and ER-positive MCF-7 breast cancer cells were used to investigate whether RF16 can inhibit the IL-8-induced breast cancer metastasis. Using growth, proliferation, and invasiveness assays, the results revealed that RF16 reduced cell proliferation, migration, and invasiveness in MDA-MB-231 cells. The RF16 peptide also regulated the protein and mRNA expressions of epithelial-mesenchymal transition (EMT) markers in IL-8-stimulated MDA-MB-231 cells. It also inhibited downstream IL-8 signaling and the IL-8-induced inflammatory response via the mitogen-activated protein kinase (MAPK) and Phosphoinositide 3-kinase (PI3K) pathways. In the xenograft tumor mouse model, RF16 synergistically reinforces the antitumor efficacy of docetaxel by improving mouse survival and retarding tumor growth. Our results indicate that RF16 significantly inhibited IL-8-stimulated cell growth, migration, and invasion in MDA-MB-231 breast cancer cells by blocking the activation of p38 and AKT cascades. It indicated that the RF16 peptide may serve as a new supplementary drug for breast cancer.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Feminino , Células MDA-MB-231 , Fosfatidilinositol 3-Quinases/metabolismo , Interleucina-8/genética , Interleucina-8/farmacologia , Transdução de Sinais , Neoplasias da Mama/patologia , Proliferação de Células , Linhagem Celular Tumoral , Movimento Celular , Transição Epitelial-Mesenquimal , Neoplasias de Mama Triplo Negativas/patologia
5.
Medicine (Baltimore) ; 101(39): e30719, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36181052

RESUMO

RATIONALE: To date, there is no actionable gene has been discovered in hepatocellular carcinoma (HCC). Tumor cells with DNA damage response and repair (DDR) gene loss-of-function mutation is sensitivity to poly-ADP-ribose polymerase (PARP) inhibitors and platinum chemotherapy in ovarian, prostate and pancreatic cancers. There is a case report demonstrated the efficacy of PARP inhibitor for BRCA2 mutation that belongs to DDR gene in HCC, which suggested the potential role of PARP inhibitor for HCC with DDR gene mutation. PATIENT CONCERNS: We reported a 44-year-old woman with non-viral HCC who was refractory to multiple treatment including target therapy, immunotherapy, and chemotherapy. The tumor tissue was submitted to next-generation sequencing using the commercially available ACTOnco®+ (ACT Genomics, Taiwan) assay that interrogates 440 and 31 cancer-related genes and fusion genes, respectively. DIAGNOSIS: A truncating mutation FANCA p.Q1307fs was also observed. The tumor was microsatellite stable and had low tumor mutational burden of 4.5 muts/Mb. INTERVENTIONS AND OUTCOMES: Given FANCA belongs to DDR genes, the inactivation evoked the idea of using PARP inhibitor and cisplatin. Therefore, the patient started to use olaparib combined with low-dose cisplatin (30 mg/m2, every 4 weeks) therapy in December 2019. Significant reduction in the tumor marker level in 1 month (PIVKA-II from 17,395 to 411 ng/dL) and follow-up CT scan showed stable disease. Her tumor did not progress until December 2020 with a progression-free survival of 12 months. LESSONS: We report the first case of FANCA-mutated HCC that responded well to olaparib and low-dose cisplatin. This addressed the potential therapeutic role of DDR gene mutation in HCC and the possible synergistic effect of PARP inhibitor and cisplatin. These findings highlight areas where further investigation and effort are needed.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Adenosina Difosfato Ribose , Adulto , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Cisplatino/uso terapêutico , Proteína do Grupo de Complementação A da Anemia de Fanconi/genética , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Masculino , Mutação , Ftalazinas , Piperazinas , Platina , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico
6.
Sci Rep ; 11(1): 1763, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33469074

RESUMO

Patients with complicated parapneumonic effusion (CPPE)/empyema have high morbidity and mortality, particularly when adequate management is delayed. We aimed to investigate novel dysregulated cytokines that can be used as biomarkers for infectious pleural effusions, especially for CPPE/empyema. Expression of 40 cytokines in parapneumonic effusions (PPE) was screened in the discovery phase, involving 63 patients, using a multiplex immunobead-based assay. Six cytokines were subsequently validated by enzyme-linked immunosorbent assays (ELISAs). We then used ELISA to further evaluate the diagnostic values and cutoff values of these cytokines as potential biomarkers in an expanded group that included 200 patients with uncomplicated parapneumonic effusion (UPPE), CPPE, empyema, transudates, other exudates, and malignant pleural effusion (MPE). The pleural levels of four cytokines (MIF, MIP-3α, IL-1ß, ENA-78) were highest and significantly increased in CPPE/empyema compared with those in other etiologies. According to receiver operating characteristic curve analysis, the four cytokines (MIF, MIP-3α, IL-1ß, and ENA-78) had areas under the curve (AUCs) greater than 0.710 for discriminating parapneumonic pleural effusion from noninfectious pleural effusions. In a comparison of nonpurulent CPPE with UPPE, logistic regression analysis revealed that pleural fluid MIF ≥ 12 ng/ml and MIP-3α ≥ 4.3 ng/ml had the best diagnostic value; MIF also displayed the highest odds ratio of 663 for nonpurulent CPPE, with 97.5% specificity, 94.44% sensitivity, and an AUC of 0.950. In conclusion, our results show that elevated MIF and MIP-3α may be used as novel biomarkers for PPE diagnosis, particularly in patients with CPPE/empyema; the findings indicate that dysregulated cytokine expression may provide clues about the pathogenesis of pleural infection.


Assuntos
Quimiocina CCL20/análise , Quimiocina CXCL5/análise , Empiema Pleural/diagnóstico , Interleucina-1beta/análise , Oxirredutases Intramoleculares/análise , Fatores Inibidores da Migração de Macrófagos/análise , Derrame Pleural/diagnóstico , Idoso , Biomarcadores/análise , Quimiocina CCL20/metabolismo , Quimiocina CXCL5/metabolismo , Empiema Pleural/patologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interleucina-1beta/metabolismo , Oxirredutases Intramoleculares/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Derrame Pleural/patologia , Estudos Prospectivos
7.
J Biopharm Stat ; 30(5): 873-881, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32394789

RESUMO

Raw materials for traditional Chinese medicine (TCM) are often from different resources and its final product may also be made by different sites. Therefore, variabilities from different resources such as site-to-site or within site component-to-component may be expected. Consequently, test for consistency in raw materials, in-process materials, and/or final product has become an important issue in the quality control (QC) process in TCM development. In this paper, a statistical QC process for raw materials and/or the final product of TCM is proposed based on a two sided [Formula: see text]-content, [Formula: see text]-confidence tolerance interval. More specifically, we construct the tolerance interval for a random-effects model to assess the QC of TCM products from different regions and possibly different product batches. The products can be claimed to be consistency when the constructed tolerance interval is within the permitted range. Given the region and batch effects, sample sizes can also be calculated to ensure the desired measure of goodness. An example is presented to illustrate the proposed approach.


Assuntos
Medicamentos de Ervas Chinesas/normas , Medicina Tradicional Chinesa/normas , Projetos de Pesquisa/estatística & dados numéricos , Simulação por Computador , Interpretação Estatística de Dados , Humanos , Modelos Estatísticos , Análise Numérica Assistida por Computador , Controle de Qualidade , Tamanho da Amostra
8.
Sci Rep ; 10(1): 4526, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32161294

RESUMO

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers worldwide. While both genetic and environmental factors have been linked to the incidence and mortality associated with CRC, an ethnic aspect of its etiology has also emerged. Since previous large-scale cancer genomics studies are mostly based on samples of European ancestry, the patterns of clinical events and associated mechanisms in other minority ethnic patients suffering from CRC are largely unexplored. We collected 104 paired and adjacent normal tissue and CRC tumor samples from Taiwanese patients and employed an integrated approach - paired expression profiles of mRNAs and microRNAs (miRNAs) combined with transcriptome-wide network analyses - to catalog the molecular signatures of this regional cohort. On the basis of this dataset, which is the largest ever reported for this type of systems analysis, we made the following key discoveries: (1) In comparison to the The Cancer Genome Atlas (TCGA) data, the Taiwanese CRC tumors show similar perturbations in expressed genes but a distinct enrichment in metastasis-associated pathways. (2) Recurrent as well as novel CRC-associated gene fusions were identified based on the sequencing data. (3) Cancer subtype classification using existing tools reveals a comparable distribution of tumor subtypes between Taiwanese cohort and TCGA datasets; however, this similarity in molecular attributes did not translate into the predicted subtype-related clinical outcomes (i.e., death event). (4) To further elucidate the molecular basis of CRC prognosis, we developed a new stratification strategy based on miRNA-mRNA-associated subtyping (MMAS) and consequently showed that repressed WNT signaling activity is associated with poor prognosis in Taiwanese CRC. In summary, our findings of distinct, hitherto unreported biosignatures underscore the heterogeneity of CRC tumorigenesis, support our hypothesis of an ethnic basis of disease, and provide prospects for translational medicine.


Assuntos
Transformação Celular Neoplásica/genética , Neoplasias Colorretais/etiologia , Perfilação da Expressão Gênica , Transcriptoma , Biomarcadores Tumorais , Neoplasias Colorretais/epidemiologia , Biologia Computacional/métodos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , MicroRNAs/genética , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Interferência de RNA , RNA Mensageiro/genética , Taiwan/epidemiologia
10.
RNA Biol ; 16(9): 1263-1274, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31135270

RESUMO

The innate immune system is the frontline host protection against pathogens. Effective antiviral immunity is elicited upon recognition of viral RNAs by the host pattern recognition receptors. One of the major viral RNA sensors is retinoic acid inducible gene-1, which triggers the production of interferons (IFNs). In turn, this protective response requires another viral sensor and immunity factor interferon-inducible protein kinase RNA activator (PACT/PRKRA). Here, we report the identification and characterization of a novel antisense PACT gene that expresses a non-coding RNA in a convergent and interferon-inducible manner. Publicly available gene structure and expression data revealed that this gene, that we termed ASPACT, overlaps with the 3' -end of the PACT locus and is highly expressed during viral infection. Our results confirm the IFN-ß-inducibility of ASPACT, which is dependent on STAT-1/2. We further discovered that downregulation of ASPACT impacts both the expression and localization of the PACT transcript. At the transcription level, ChIP and ChIRP assays demonstrated that the ASPACT non-coding RNA occupies distinct chromatin regions of PACT gene and is important for promoter recruitment of the epigenetic silencer HDAC1. In parallel, ASPACT was also found to mediate nuclear retention of the PACT mRNA via direct RNA-RNA interaction, as revealed by RNA antisense purification assay. In summary, our results support the model that the non-coding RNA ASPACT acts as a negative regulator of PACT at multiple levels, and reveal a novel regulator of the viral counteractive response.


Assuntos
RNA Antissenso/metabolismo , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Núcleo Celular/metabolismo , Epigênese Genética , Células HEK293 , Células HeLa , Histona Desacetilase 1/metabolismo , Humanos , Imunidade Inata , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Transcrição Gênica
11.
Faraday Discuss ; 215(0): 297-312, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-30942206

RESUMO

We report on a simple and facile synthetic approach for preparing both a CuBi2O4 photocathode and BiVO4 photoanode from a single Bi4O5I2 nanosheet template. A nanosheet structured Bi4O5I2 (nanoBi4O5I2) template, solvothermally deposited on a conducting glass substrate, can be converted to a textured CuBi2O4 photocathode and a BiVO4 photoanode with coral-like nanostructure by drop-casting a copper ion-containing and a vanadium ion-containing solution, respectively, with a follow-up heat treatment. UV-vis absorption spectra and Mott-Schottky analyses confirm CuBi2O4 and BiVO4 have well-suited band gaps for absorbing a large portion of visible light and complementary band structures for proton reduction and water oxidation, respectively. A photoelectrochemical tandem cell, consisting of a cobalt based catalyst modified CuBi2O4 photocathode and a cobalt based catalyst modified BiVO4 photoanode shows promising photoelectrochemical properties towards water splitting, and can be operated without an external bias. Factors limiting the performance of the tandem cell are also discussed.

12.
Theranostics ; 8(2): 486-504, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29290822

RESUMO

During neoplastic development, a multitude of changes in genome-encoded information are progressively selected to confer growth and survival advantages to tumor cells. microRNAs-mRNAs regulatory networks, given their role as a critical layer of robust gene expression control, are frequently altered in neoplasm. However, whether and how these gene perturbations impact metabolic homeostasis remains largely unresolved. Methods: Through targeted miRNA expression screening, we uncovered an oral squamous cell carcinoma (OSCC)-associated miRNAome, among which miR-31-5p was identified based on extent of up-regulation, functional impact on OSCC cell migration and invasion, and direct regulation of the rate-limiting enzyme in peroxisomal ß-oxidation, ACOX1. Results: We further found that both miR-31-5p and ACOX1 underpin, in an antagonistic manner, the overall cellular lipidome profiles as well as the migratory and invasive abilities of OSCC cells. Interestingly, the extracellular levels of prostaglandin E2 (PGE2), a key substrate of ACOX1, were controlled by the miR-31-5p-ACOX1 axis, and were shown to positively influence the extent of cell motility in correlation with metastatic status. The promigratory effect of this metabolite was mediated by an elevation in EP1-ERK-MMP9 signaling. Of note, functional significance of this regulatory pathway was further corroborated by its clinicopathologically-correlated expression in OSCC patient specimens. Conclusions: Collectively, our findings outlined a model whereby misregulated miR-31-5p-ACOX1 axis in tumor alters lipid metabolomes, consequently eliciting an intracellular signaling change to enhance cell motility. Our clinical analysis also unveiled PGE2 as a viable salivary biomarker for prognosticating oral cancer progression, further underscoring the importance of lipid metabolism in tumorigenesis.


Assuntos
Acil-CoA Oxidase/genética , Carcinogênese/genética , Carcinoma de Células Escamosas/genética , Dinoprostona/metabolismo , MicroRNAs/genética , Neoplasias Bucais/genética , Biomarcadores Tumorais/genética , Carcinogênese/patologia , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Bucais/patologia , Transdução de Sinais/genética , Regulação para Cima/genética
13.
Stat Med ; 35(14): 2301-14, 2016 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-26833851

RESUMO

In recent years, developing pharmaceutical products via multiregional clinical trials (MRCTs) has become standard. Traditionally, an MRCT would assume that a treatment effect is uniform across regions. However, heterogeneity among regions may have impact upon the evaluation of a medicine's effect. In this study, we consider a random effects model using discrete distribution (DREM) to account for heterogeneous treatment effects across regions for the design and evaluation of MRCTs. We derive an power function for a treatment that is beneficial under DREM and illustrate determination of the overall sample size in an MRCT. We use the concept of consistency based on Method 2 of the Japanese Ministry of Health, Labour, and Welfare's guidance to evaluate the probability for treatment benefit and consistency under DREM. We further derive an optimal sample size allocation over regions to maximize the power for consistency. Moreover, we provide three algorithms for deriving sample size at the desired level of power for benefit and consistency. In practice, regional treatment effects are unknown. Thus, we provide some guidelines on the design of MRCTs with consistency when the regional treatment effect are assumed to fall into a specified interval. Numerical examples are given to illustrate applications of the proposed approach. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Ensaios Clínicos como Assunto/estatística & dados numéricos , Modelos Estatísticos , Algoritmos , Bioestatística , Humanos , Estudos Multicêntricos como Assunto/estatística & dados numéricos , Probabilidade , Tamanho da Amostra , Resultado do Tratamento
14.
Chem Sci ; 7(7): 4024-4035, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30155045

RESUMO

Splitting water into hydrogen and oxygen with molecular catalysts and light has been a long-established challenge. Approaches in homogeneous systems have been met with little success and the integration of molecular catalysts in photoelectrochemical cells is challenging due to inaccessibility and incompatibility of functional hybrid molecule/material electrodes with long-term stability in aqueous solution. Here, we present the first example of light-driven water splitting achieved with precious-metal-free molecular catalysts driving both oxygen and hydrogen evolution reactions. Mesoporous TiO2 was employed as a low-cost scaffold with long-term stability for anchoring a phosphonic acid-modified nickel(ii) bis-diphosphine catalyst (NiP) for electrocatalytic proton reduction. A turnover number of 600 mol H2 per mol NiP was achieved after 8 h controlled-potential electrolysis at a modest overpotential of 250 mV. X-ray photoelectron, UV-vis and IR spectroscopies confirmed that the molecular structure of the Ni catalyst remains intact after prolonged hydrogen production, thereby reasserting the suitability of molecular catalysts in the development of effective, hydrogen-evolving materials. The relatively mild operating conditions of a pH 3 aqueous solution allowed this molecule-catalysed cathode to be combined with a molecular Fe(ii) catalyst-modified WO3 photoanode in a photoelectrochemical cell. Water splitting into H2 and O2 was achieved under solar light illumination with an applied bias of >0.6 V, which is below the thermodynamic potential (1.23 V) for water splitting and therefore allowed the storage of solar energy in the fuel H2.

15.
Chemistry ; 21(10): 3919-23, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-25650832

RESUMO

An efficient, stable and scalable hybrid photoelectrode for visible-light-driven H2 generation in an aqueous pH 9.2 electrolyte solution is reported. The photocathode consists of a p-type Si substrate layered with a Ti and Ni-containing composite film, which acts as both a protection and electrocatalyst layer on the Si substrate. The film is prepared by the simple drop casting of the molecular single-source precursor, [{Ti2(OEt)9(NiCl)}2] (TiNipre), onto the p-Si surface at room temperature, followed by cathodic in situ activation to form the catalytically active TiNi film (TiNicat). The p-Si|TiNicat photocathode exhibits prolonged hydrogen generation with a stable photocurrent of approximately -5 mA cm(-2) at 0 V vs. RHE in an aqueous pH 9.2 borate solution for several hours, and serves as a benchmark non-noble photocathode for solar H2 evolution that operates efficiently under neutral-alkaline conditions.

16.
Faraday Discuss ; 176: 199-211, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25434986

RESUMO

This discussion describes a direct comparison of photoelectrochemical (PEC) water oxidation activity between a photosystem II (PSII)-functionalised photoanode and a synthetic nanocomposite photoanode. The semi-biological photoanode is composed of PSII from the thermophilic cyanobacterium Thermosynechococcus elongatus on a mesoporous indium tin oxide electrode (mesoITO|PSII). PSII embeds all of the required functionalities for light absorption, charge separation and water oxidation and ITO serves solely as the electron collector. The synthetic photoanode consists of a TiO(2) and NiO(x) coated nanosheet-structured WO(3) electrode (nanoWO(3)|TiO(2)|NiO(x)). The composite structure of the synthetic electrode allows mimicry of the functional key features in PSII: visible light is absorbed by WO(3), TiO(2) serves as a protection and charge separation layer and NiO(x) serves as the water oxidation electrocatalyst. MesoITO|PSII uses low energy red light, whereas nanoWO(3)|TiO(2)|NiO(x) requires high energy photons of blue-end visible and UV regions to oxidise water. The electrodes have a comparable onset potential at approximately 0.6 V vs. reversible hydrogen electrode (RHE). MesoITO|PSII reaches its saturation photocurrent at 0.84 V vs. RHE, whereas nanoWO(3)|TiO(2)NiO(x) requires more than 1.34 V vs. RHE. This suggests that mesoITO|PSII suffers from fewer limitations from charge recombination and slow water oxidation catalysis than the synthetic electrode. MesoITO|PSII displays a higher 'per active' site activity, but is less photostable and displays a much lower photocurrent per geometrical surface area and incident photon to current conversion efficiency (IPCE) than nanoWO(3)|TiO(2)|NiO(x_.

17.
J Biopharm Stat ; 23(5): 1054-66, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23957515

RESUMO

Recently, biosimilars have attracted much attention from sponsors and regulatory authorities, while patents on early biological products will soon expire in the next few years. The European Medicines Agency (EMEA) of the European Union (EU) published a guideline on similar biological medicinal products for approval of these products in 2005 . Based on the foundational principles of the EMEA guideline, biosimilars are expected to be similar, not identical, to the innovator biologics they seek to copy. In this article, we develop a consistency approach for assessment of similarity between a biosimilar product and the innovator biologic. A method for sample size determination for conducting a clinical trial to assess the biosimilar product is also proposed. A numerical example is given to illustrate applications of the proposed approach in different scenarios.


Assuntos
Medicamentos Biossimilares , Modelos Estatísticos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Medicamentos Biossimilares/efeitos adversos , Medicamentos Biossimilares/farmacocinética , Medicamentos Biossimilares/uso terapêutico , Aprovação de Drogas/estatística & dados numéricos , Europa (Continente) , Guias como Assunto , Tamanho da Amostra , Equivalência Terapêutica , Estados Unidos
18.
Chemistry ; 19(39): 12943-7, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-23946244

RESUMO

Photoactive in one step! A nanocomposite water-oxidation photocatalyst was assembled by a straightforward and one-step spin-coating procedure of a Ti- and Ni-containing molecule on nanostructured WO3. The photoanode oxidizes water to O2 with good activity and stability in alkaline solution, and thereby features light absorption, charge separation and water-oxidation catalysis (see scheme).

19.
Neurorehabil Neural Repair ; 27(5): 439-47, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23353185

RESUMO

BACKGROUND: Arm nonuse, defined as the difference between what the individual can do when constrained to use the paretic arm and what the individual does when given a free choice to use either arm, has not yet been quantified in individuals poststroke. OBJECTIVES: (1) To quantify nonuse poststroke and (2) to develop and test a novel, simple, objective, reliable, and valid instrument, the Bilateral Arm Reaching Test (BART), to quantify arm use and nonuse poststroke. METHODS: First, we quantify nonuse with the Quality of Movement (QOM) subscale of the Actual Amount of Use Test (AAUT) by subtracting the AAUT QOM score in the spontaneous use condition from the AAUT QOM score in a subsequent constrained use condition. Second, we quantify arm use and nonuse with BART by comparing reaching performance to visual targets projected over a 2D horizontal hemi-work space in a spontaneous-use condition (in which participants are free to use either arm at each trial) with reaching performance in a constrained-use condition. RESULTS: All participants (N = 24) with chronic stroke and with mild to moderate impairment exhibited nonuse with the AAUT QOM. Nonuse with BART had excellent test-retest reliability and good external validity. CONCLUSIONS: BART is the first instrument that can be used repeatedly and practically in the clinic to quantify the effects of neurorehabilitation on arm use and nonuse and in the laboratory for advancing theoretical knowledge about the recovery of arm use and the development of nonuse and "learned nonuse" after stroke.


Assuntos
Braço/fisiopatologia , Terapia por Exercício/métodos , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/patologia , Idoso , Avaliação da Deficiência , Feminino , Lateralidade Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Reprodutibilidade dos Testes
20.
Chem Commun (Camb) ; 49(39): 4331-3, 2013 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-22918295

RESUMO

Cobalt-containing polyoxotitanates (TiCo) are excellent precursors for the simple and scalable preparation of Nocera-type CoOx water-oxidation electrocatalysts. The TiCo cages serve as a reservoir for cobalt ions in a titania matrix on fluoride-doped tin oxide electrodes, and form, in situ, the active CoOx catalyst for O2 evolution with high stability in phosphate buffer in pH neutral water.

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