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1.
Cell Mol Life Sci ; 80(8): 239, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37540379

RESUMO

Retinal ganglion cells (RGCs) are essential for vision perception. In glaucoma and other optic neuropathies, RGCs and their optic axons undergo degenerative change and cell death; this can result in irreversible vision loss. Here we developed a rapid protocol for directly inducing RGC differentiation from human induced pluripotent stem cells (hiPSCs) by the overexpression of ATOH7, BRN3B, and SOX4. The hiPSC-derived RGC-like cells (iRGCs) show robust expression of various RGC-specific markers by whole transcriptome profiling. A functional assessment was also carried out and this demonstrated that these iRGCs display stimulus-induced neuronal activity, as well as spontaneous neuronal activity. Ethambutol (EMB), an effective first-line anti-tuberculosis agent, is known to cause serious visual impairment and irreversible vision loss due to the RGC degeneration in a significant number of treated patients. Using our iRGCs, EMB was found to induce significant dose-dependent and time-dependent increases in cell death and neurite degeneration. Western blot analysis revealed that the expression levels of p62 and LC3-II were upregulated, and further investigations revealed that EMB caused a blockade of lysosome-autophagosome fusion; this indicates that impairment of autophagic flux is one of the adverse effects of that EMB has on iRGCs. In addition, EMB was found to elevate intracellular reactive oxygen species (ROS) levels increasing apoptotic cell death. This could be partially rescued by the co-treatment with the ROS scavenger NAC. Taken together, our findings suggest that this iRGC model, which achieves both high yield and high purity, is suitable for investigating optic neuropathies, as well as being useful when searching for potential drugs for therapeutic treatment and/or disease prevention.


Assuntos
Células-Tronco Pluripotentes Induzidas , Doenças do Nervo Óptico , Humanos , Células Ganglionares da Retina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Doenças do Nervo Óptico/metabolismo , Apoptose , Etambutol/farmacologia , Etambutol/metabolismo , Fatores de Transcrição SOXC/metabolismo
2.
Methods Mol Biol ; 2683: 53-68, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37300766

RESUMO

The generation of a homogeneous population of microglia from human induced pluripotent stem cells (hiPSCs) is crucial to modeling neurological disorders, as well as the carrying out of drug screening and toxicity testing. Here, we provide a stepwise protocol for the simple, robust, and efficient differentiation of hiPSCs into microglia-like cells (iMGs) by overexpression of SPI1 and CEBPA. This protocol details hiPSC culture, lentivirus production, lentivirus delivery, and, finally, the differentiation and validation of the iMG cells.


Assuntos
Células-Tronco Pluripotentes Induzidas , Humanos , Fatores de Transcrição , Microglia , Diferenciação Celular/genética , Células Cultivadas
3.
Int J Mol Sci ; 23(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36430662

RESUMO

Asthma is a chronic respiratory disease with symptoms such as expiratory airflow narrowing and airway hyperresponsiveness (AHR). Millions of people suffer from asthma and are at risk of life-threatening conditions. Lactoferrin (LF) is a glycoprotein with multiple physiological functions, including antioxidant, anti-inflammatory, antimicrobial, and antitumoral activities. LF has been shown to function in immunoregulatory activities in ovalbumin (OVA)-induced delayed type hypersensitivity (DTH) in mice. Hence, the purpose of this study was to investigate the roles of LF in AHR and the functions of dendritic cells (DCs) and Th2-related responses in asthma. Twenty 8-week-old male BALB/c mice were divided into normal control (NC), ovalbumin (OVA)-sensitized, and OVA-sensitized with low dose of LF (100 mg/kg) or high dose of LF (300 mg/kg) treatment groups. The mice were challenged by intranasal instillation with 5% OVA on the 21st to 27th day after the start of the sensitization period. The AHR, cytokines in bronchoalveolar lavage fluid, and pulmonary histology of each mouse were measured. Serum OVA-specific IgE and IgG1 and OVA-specific splenocyte responses were further detected. The results showed that LF exhibited protective effects in ameliorating AHR, as well as lung inflammation and damage, in reducing the expression of Th2 cytokines and the secretion of allergen-specific antibodies, in influencing the functions of DCs, and in decreasing the level of Th2 immune responses in a BALB/c mouse model of OVA-induced allergic asthma. Importantly, we demonstrated that LF has practical application in reducing DC-induced Th2 cell responses in asthma. In conclusion, LF exhibits anti-inflammation and immunoregulation activities in OVA-induced allergic asthma. These results suggest that LF may act as a supplement to prevent asthma-induced lung injury and provide an additional agent for reducing asthma severity.


Assuntos
Asma , Lactoferrina , Células Th2 , Animais , Masculino , Camundongos , Asma/induzido quimicamente , Asma/tratamento farmacológico , Citocinas/metabolismo , Lactoferrina/farmacologia , Lactoferrina/uso terapêutico , Lactoferrina/metabolismo , Camundongos Endogâmicos BALB C , Ovalbumina , Células Th2/efeitos dos fármacos , Células Th2/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo
4.
Opt Express ; 30(12): 21184-21194, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-36224843

RESUMO

High pattern fidelity is paramount to the performance of metalenses and metasurfaces, but is difficult to achieve using economic photolithography technologies due to low resolutions and limited process windows of diverse subwavelength structures. These hurdles can be overcome by photomask sizing or reshaping, also known as optical proximity correction (OPC). However, the lithographic simulators critical to model-based OPC require precise calibration and have not yet been specifically developed for metasurface patterning. Here, we demonstrate an accurate lithographic model based on Hopkin's image formulation and fully convolutional networks (FCN) to control the critical dimension (CD) patterning of a near-infrared (NIR) metalens through a distributed OPC flow using i-line photolithography. The lithographic model achieves an average ΔCD/CD = 1.69% due to process variations. The model-based OPC successfully produces the 260 nm CD in a metalens layout, which corresponds to a lithographic constant k1 of 0.46 and is primarily limited by the resolution of the photoresist. Consequently, our fabricated NIR metalens with a diameter of 1.5 mm and numerical aperture (NA) of 0.45 achieves a measured focusing efficiency of 64%, which is close to the calculated value of 69% and among the highest reported values using i-line photolithography.

5.
Toxics ; 10(4)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35448434

RESUMO

Air pollution triggers a tissue-specific inflammatory response. However, studies on the association between exposure to air pollutants and chronic rhinosinusitis (CRS) risk remain limited. Thus, we conducted this nationwide study to define the association between air pollution and CRS. We used the Longitudinal Health Insurance Database (LHID) and Taiwan Air Quality-Monitoring Database (TAQMD) to conduct a population-based cohort study. Study participants were recruited from the LHID, a data subset of the National Health Insurance Research Database that randomly sampled one million individuals. TAQMD has been an air pollutant database since 1998. In univariate and multivariate Cox proportional hazards regression models, adjusted hazard ratios (aHRs) and 95% CIs of CRS in five air pollutants were accounted. We adjusted for age, sex, urbanization level, insurance fee, comorbidities, and pollutant levels in the multivariate model. The total number of participants enrolled in this study was 160,504. The average age was 40.46 ± 14.62 years; males constituted 43.8% of the total participants. The percentages of alcoholism, tobacco dependence, and COPD were 1.5%, 2.8%, and 28.3%, respectively. After adjustment for age, sex, urbanization level, insurance fee, and comorbidities, the highest levels of air pollutants, including PM2.5 (aHR = 1.14, 95% CI = 1.06-1.22), NO2 (aHR = 1.07, 95% CI = 1.00-1.15), and PM10 (aHR = 1.13, 95% CI = 1.05-1.21) had a significantly greater CRS risk; we selected the lower concentration as the reference but did not correlate with CO. We found a significantly increased risk of CRS in residents with air pollutant exposure.

6.
Artigo em Inglês | MEDLINE | ID: mdl-34770089

RESUMO

The development of the biotech industry is in full swing, and consumers have begun to value biotech brands. Since biotech products often focus on the future or special benefits, consumers inevitably bear certain risks when purchasing biotech products, and their trust in the biotech brand will have an important impact on their purchase intention. Previous studies have lacked a targeted understanding of consumer trust in biotech brands and a discussion of cultural viewpoints. This study introduced the concept of personal connections in Chinese relationalism and trust strategies in Chinese society to address this gap. In-depth interviews and focus group discussions were conducted in collaboration with Company X, a listed Taiwanese cord blood company, to extract the key factors influencing consumer trust and purchase intention of biotech brands. After constructing the structure model, the study was validated using a structural equation model through investigation and survey. The findings indicated that consumer trust in biotech brands was constructed by a combination of kinship trust transfer and emergent trust transfer within the consumer relationship network, as well as institutional trust and professional trust outside the relationship network and that a significant positive correlation existed between consumer trust in biotech brands and purchase intention. The acquaintances within the consumer relationship network include not only relatives and friends but also health care workers and netizens that consumers come into contact with. In addition, kinship trust transfer and emergent trust transfer within the consumer relationship network have a greater impact on trust in biotech brands than the institutional trust and professional trust outside the relationship network. The findings of this study deepen the understanding of consumer trust in biotech brands across cultures, and suggest that future marketing communication should be expanded to include key players within the consumer relationship network.


Assuntos
Intenção , Confiança , Biotecnologia , Comportamento do Consumidor , Sangue Fetal , Humanos
7.
Stem Cell Reports ; 16(5): 1363-1380, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33836143

RESUMO

Microglia, the immune cells of the central nervous system, play critical roles in brain physiology and pathology. We report a novel approach that produces, within 10 days, the differentiation of human induced pluripotent stem cells (hiPSCs) into microglia (iMG) by forced expression of both SPI1 and CEBPA. High-level expression of the main microglial markers and the purity of the iMG cells were confirmed by RT-qPCR, immunostaining, and flow cytometry analyses. Whole-transcriptome analysis demonstrated that these iMGs resemble human fetal/adult microglia but not human monocytes. Moreover, these iMGs exhibited appropriate physiological functions, including various inflammatory responses, ADP/ATP-evoked migration, and phagocytic ability. When co-cultured with hiPSC-derived neurons, the iMGs respond and migrate toward injured neurons. This study has established a protocol for the rapid conversion of hiPSCs into functional iMGs, which should facilitate functional studies of human microglia using different disease models and also help with drug discovery.


Assuntos
Diferenciação Celular , Células-Tronco Pluripotentes Induzidas/citologia , Microglia/citologia , Fatores de Transcrição/metabolismo , Difosfato de Adenosina/farmacologia , Trifosfato de Adenosina/farmacologia , Biomarcadores/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Movimento Celular/efeitos dos fármacos , Meios de Cultura/farmacologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Microglia/efeitos dos fármacos
8.
Talanta ; 192: 471-477, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30348420

RESUMO

Over the past decades, the synthesis of carbohydrate polymers incorporated graphene or reduced graphene oxide has received greater attention in different disciplines owing to their unique physicochemical properties. In this context, we report a facile electrochemical synthesis of cellulose microfibers supported reduced graphene oxide and its application towards enhanced and lower potential electrochemical detection of fenitrothion. The synthesized cellulose microfibers supported reduced graphene oxide composite was further characterized using Fourier-transform infrared spectroscopy, Raman spectroscopy and high resolution scanning electron microscopy. Cyclic voltammetry studies reveal that cellulose microfibers supported reduced graphene oxide composite modified screen-printed carbon electrode exhibits a superior electro-reduction ability and lower reduction potential towards fenitrothion compared to screen-printed carbon electrodes modified with graphene oxide, graphene oxide-cellulose microfibers, and reduced graphene oxide. Furthermore, cellulose microfibers supported reduced graphene oxide composite modified electrode showed 141 mV lower reduction potential towards fenitrothion than the chemically reduced graphene oxide- cellulose microfibers composite modified screen-printed carbon electrode. The effect of accumulation time, catalyst loading, scan rate and pH for the detection of fenitrothion has been studied and discussed. Differential pulse voltammetric studies show that the fabricated composite electrode can detect the fenitrothion in a wider linear response range up to 1.134 mM with a detection limit of 8 nM. To validate the proof of concept, the fabricated sensor was successfully applied for the detection of fenitrothion in different water samples.

9.
Clin Biomech (Bristol, Avon) ; 60: 30-38, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30308435

RESUMO

BACKGROUND: In this study, we seek to replace conventional force platforms with a single accelerometer for measuring Center of Pressure trajectories, in order to achieve portability and convenience without sacrificing accuracy. METHODS: We measure the actual Anterior/Posterior and Medial/Lateral Center of Pressure trajectories of ten healthy young subjects using a force platform, and compare them with estimated measurements derived from accelerometer signals collected from three body locations (upper trunk, waist, and lower thigh) using three machine learning algorithms (Neural Network, Genetic Algorithm, and Adaptive Network-based Fuzzy Inference System). Error ratios and correlation coefficients corresponding to body locations were compared via one-way repeated-measures ANOVA. The ratios and coefficients corresponding to the three algorithms were also compared using the same approach. FINDINGS: Estimated Anterior/Posterior trajectories indicated that measurements collected from the waist provided the lowest margins of error (8.1-8.4% v. 12.1-13.4%, P ≤ .001) and the highest correlation (.95 v. .82-.86, P ≤ .032). Estimated Medial/Lateral trajectories indicated that measurements collected from both the waist and thigh, as compared to the upper trunk, provided lower margins of error (7.0-7.3% v. 8.5-10.8%). In general, the waist is the better accelerometer attachment location. INTERPRETATION: The results of our study corroborate our deduction that the high correlation between Center of Pressure and body's Center of Mass provides the rationale to place the single accelerometer close to the waist for Center of Pressure estimations. This study also supports the feasibility of using one single accelerometer programmed with algorithms for similar clinical applications.


Assuntos
Acelerometria/métodos , Postura/fisiologia , Acelerometria/instrumentação , Adulto , Algoritmos , Lógica Fuzzy , Humanos , Redes Neurais de Computação , Pressão , Rotação , Coxa da Perna , Tronco , Adulto Jovem
10.
Biometrics ; 74(3): 881-890, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29270978

RESUMO

This article mainly focuses on analyzing covariate data from incident and prevalent cohort studies and a prevalent sample with only baseline covariates of interest and truncation times. Our major task in both research streams is to identify the effects of covariates on a failure time through very general single-index survival regression models without observing survival outcomes. With a strict increase of the survival function in the linear predictor, the ratio of incident and prevalent covariate densities is shown to be a non-degenerate and monotonic function of the linear predictor under covariate-independent truncation. Without such a structural assumption, the conditional density of a truncation time in a prevalent cohort is ensured to be a non-degenerate function of the linear predictor. In light of these features, some innovative approaches, which are based on the maximum rank correlation estimation or the pseudo least integrated squares estimation, are developed to estimate the coefficients of covariates up to a scale factor. Existing theoretical results are further used to establish the n -consistency and asymptotic normality of the proposed estimators. Moreover, extensive simulations are conducted to assess and compare the finite-sample performance of various estimators. To illustrate the methodological ideas, we also analyze data from the Worcester Heart Attack Study and the National Comorbidity Survey Replication.


Assuntos
Modelos Estatísticos , Análise de Regressão , Análise de Sobrevida , Análise de Variância , Comorbidade/tendências , Simulação por Computador , Incidência , Infarto do Miocárdio/epidemiologia , Prevalência , Estatística como Assunto/métodos
11.
World J Surg Oncol ; 15(1): 230, 2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29284496

RESUMO

BACKGROUND: Carcinoembryonic antigen (CEA) is one of the most widely used tumor markers, and its value in the surveillance of post-operative colorectal cancer is well established. Fluorodeoxyglucose-positron emission tomography (FDG-PET) has been clinically used in colorectal cancer imaging including preoperative staging, evaluation of therapeutic response, detection of disease recurrence, and investigation of unexplained rising tumor markers. CASE PRESENTATION: We report a case of resected colorectal cancer presented with rising CEA levels in 5 years, and FDG-PET revealed no definitive evidence of recurrence except abnormal focal FDG uptake in the right thyroid lobe. However, fine needle aspiration cytology (FNAC) of the thyroid nodule showed negative for malignancy. Progressively rising CEA levels were noted over the following 5 years, but serial follow-up examinations did not find evidence of recurrence. Fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) was performed subsequently and again showed focal FDG uptake in the right thyroid lobe. This time, FNAC revealed positive for malignancy, in favor of medullary thyroid carcinoma (MTC). The patient underwent total thyroidectomy and modified radical neck dissection, and MTC with cervical nodal metastasis (pT3N1) was diagnosed. He had cervical lymph nodes recurrence 2 years later, which was resected. CONCLUSIONS: This case reminded us that FDG-PET/CT may detect occult tumors resulting in CEA elevation other than colorectal cancer. Moreover, FNA has a higher false negative rate in detecting MTC than other forms of thyroid cancer. Repeat FNAC for the initial negative cytology result and measure of serum calcitonin for the early MTC detection could be more helpful to avoid the delay in MTC diagnosis.


Assuntos
Biomarcadores Tumorais/sangue , Antígeno Carcinoembrionário/sangue , Carcinoma Neuroendócrino/diagnóstico , Neoplasias Colorretais/complicações , Diagnóstico Tardio , Neoplasias da Glândula Tireoide/diagnóstico , Carcinoma Neuroendócrino/diagnóstico por imagem , Carcinoma Neuroendócrino/etiologia , Carcinoma Neuroendócrino/cirurgia , Neoplasias Colorretais/sangue , Neoplasias Colorretais/cirurgia , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/etiologia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia
12.
Med Biol Eng Comput ; 54(2-3): 485-96, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26109520

RESUMO

Parkinson's disease (PD) is a neurodegenerative disease of the central nervous system that results from the degeneration of dopaminergic neurons in the substantia nigra. Abnormal gait begins in the early stage and becomes severe as the disease progresses; therefore, the assessment of gait becomes an important issue in evaluating the progression of PD and the effectiveness of treatment. To provide a clinically useful gait assessment in environments with budget and space limitations, such as a small clinic or home, we propose and develop a portable method utilizing the monocular image sequences of walking to track and analyze a Parkinsonian gait pattern. In addition, a centroid tracking algorithm is developed and used here to enhance the method of quantifying kinematic gait parameters of PD in different states. Twelve healthy subjects and twelve mild patients with PD participate in this study. This method requires one digital video camera and subjects with two joint markers attached on the fibula head and the lateral malleolus of the leg. All subjects walk with a natural pace in front of a video camera during the trials. Results of our study demonstrate the stride length and walking velocity significantly decrease in PD without drug compared to PD with drug in both proposed method and simultaneous gait assessment performed by GAITRite(®) system. In gait initiation, step length and swing velocity also decrease in PD without drug compared to both PD with drug and controls. Our results showed high correlation in gait parameters between the two methods and prove the reliability of the proposed method. With the proposed method, quantitative measurement and analysis of Parkinsonian gait could be inexpensive to implement, portable within a small clinic or home, easy to administer, and simple to interpret. Although this study is assessed Parkinsonian gait, the proposed method has the potential to help clinicians and researchers assess the gait of patients with other neuromuscular diseases, such as traumatic brain injury and stroke patients.


Assuntos
Algoritmos , Marcha/fisiologia , Processamento de Imagem Assistida por Computador , Doença de Parkinson/fisiopatologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
13.
J Invest Dermatol ; 135(8): 2012-2020, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25815426

RESUMO

The inflammasome is a complex of proteins that has a critical role in mounting an inflammatory response in reply to a harmful stimulus that compromises the homeostatic state of the tissue. The NLRP3 inflammasome, which is found in a wound-like environment, is comprised of three components: the NLRP3, the adaptor protein ASC and caspase-1. Interestingly, although ASC levels do not fluctuate, caspase-1 levels are elevated in both physiological and pathological conditions. Despite the observation that merely raising caspase-1 levels is sufficient to induce inflammation, the crucial question regarding the mechanism governing its expression is unexplored. We found that, in an inflammatory microenvironment, caspase-1 is regulated by NF-κB. Consistent with this association, the inhibition of caspase-1 activity parallels the effects on wound healing caused by the abrogation of NF-κB activation. Surprisingly, not only does inhibition of the NF-κB/caspase-1 axis disrupt the inflammatory phase of the wound-healing program, but it also impairs the stimulation of cutaneous epithelial stem cells of the proliferative phase. These data provide a mechanistic basis for the complex interplay between different phases of the wound-healing response in which the downstream signaling activity of immune cells can kindle the amplification of local stem cells to advance tissue repair.


Assuntos
Caspase 1/fisiologia , Microambiente Celular/fisiologia , Dermatite/patologia , Dermatite/fisiopatologia , Queratinócitos/patologia , Animais , Caspase 8/genética , Caspase 8/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Homeostase/fisiologia , Técnicas In Vitro , Camundongos , Camundongos Knockout , NF-kappa B/genética , NF-kappa B/fisiologia , Transdução de Sinais/fisiologia , Cicatrização/fisiologia
14.
Sleep ; 38(2): 213-21, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25409108

RESUMO

STUDY OBJECTIVES: Sleep apnea (SA) is characterized by apnea during sleep and is associated with cardiovascular diseases and an increase in all-cause mortality. Chronic kidney disease (CKD) is a global health problem that has placed a substantial burden on healthcare resources. However, the relationship between SA and the incidence of CKD is not clear. This study aimed to determine whether SA is an independent risk factor for the development of CKD. DESIGN: Retrospective cohort study. SETTING: National Health Insurance Research Database (NHIRD) of Taiwan. PATIENTS OR PARTICIPANTS: A total of 4,674 adult patients (age ≥ 30 y) in whom SA was newly diagnosed from 2000 to 2010 were included, together with 23,370 non-SA patients as the comparison group. The two groups were frequency-matched for sex, age, and year of receiving medical service. Each individual was followed until 2011. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: These two groups were monitored and observed for the occurrence of CKD. Patients with SA experienced a 1.94-fold increase (95% confidence interval [CI], 1.52-2.46; P < 0.001) in the incidence of CKD, which was independent of sex, age, and comorbid medical conditions. Additionally, they showed a 2.2-fold increase (95% CI, 1.31-3.69; P < 0.01) in the incidence of end-stage renal disease (ESRD). CONCLUSIONS: Patients with sleep apnea are at increased risk for chronic kidney disease and end-stage renal disease compared with the general population. As such, screening renal function and treatment of chronic kidney disease is an important issue in patients with sleep apnea.


Assuntos
Insuficiência Renal Crônica/complicações , Síndromes da Apneia do Sono/complicações , Adulto , Feminino , Humanos , Incidência , Falência Renal Crônica/complicações , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/fisiopatologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Síndromes da Apneia do Sono/epidemiologia , Síndromes da Apneia do Sono/fisiopatologia , Taiwan/epidemiologia
15.
ACS Nano ; 7(12): 10780-7, 2013 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-24224917

RESUMO

Interface carrier recombination currently hinders the performance of hybrid organic-silicon heterojunction solar cells for high-efficiency low-cost photovoltaics. Here, we introduce an intermediate 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC) layer into hybrid heterojunction solar cells based on silicon nanowires (SiNWs) and conjugate polymer poly(3,4-ethylenedioxy-thiophene):poly(styrenesulfonate) (PEDOT:PSS). The highest power conversion efficiency reaches a record 13.01%, which is largely ascribed to the modified organic surface morphology and suppressed saturation current that boost the open-circuit voltage and fill factor. We show that the insertion of TAPC increases the minority carrier lifetime because of an energy offset at the heterojunction interface. Furthermore, X-ray photoemission spectroscopy reveals that TAPC can effectively block the strong oxidation reaction occurring between PEDOT:PSS and silicon, which improves the device characteristics and assurances for reliability. These learnings point toward future directions for versatile interface engineering techniques for the attainment of highly efficient hybrid photovoltaics.

16.
PLoS One ; 8(3): e60509, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23544151

RESUMO

This study explores the force synergy of human digits in both static and dynamic cylindrical grasping conditions. The patterns of digit force distribution, error compensation, and the relationships among digit forces are examined to quantify the synergetic patterns and coordination of multi-finger movements. This study recruited 24 healthy participants to perform cylindrical grasps using a glass simulator under normal grasping and one-finger restricted conditions. Parameters such as the grasping force, patterns of digit force distribution, and the force coefficient of variation are determined. Correlation coefficients and principal component analysis (PCA) are used to estimate the synergy strength under the dynamic grasping condition. Specific distribution patterns of digit forces are identified for various conditions. The compensation of adjacent fingers for the force in the normal direction of an absent finger agrees with the principle of error compensation. For digit forces in anti-gravity directions, the distribution patterns vary significantly by participant. The forces exerted by the thumb are closely related to those exerted by other fingers under all conditions. The index-middle and middle-ring finger pairs demonstrate a significant relationship. The PCA results show that the normal forces of digits are highly coordinated. This study reveals that normal force synergy exists under both static and dynamic cylindrical grasping conditions.


Assuntos
Dedos/fisiologia , Força da Mão/fisiologia , Adulto , Fenômenos Biomecânicos/fisiologia , Feminino , Humanos , Masculino , Postura/fisiologia , Análise de Componente Principal
17.
Clin Biomech (Bristol, Avon) ; 28(5): 549-54, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23583096

RESUMO

BACKGROUND: Pain that accompanies anterior cruciate ligament deficiency during dynamic knee extension exercises is usually caused by excessive anterior tibial translation, which can be restricted if the anterior cruciate ligament was intact. METHODS: A functional electrical stimulator is incorporated with a training device to induce hamstring contractions during certain degrees of knee extension to replicate effects similar to those generated by an intact anterior cruciate ligament and to reduce anterior tibial translation. By using a camera that tracks markers placed on bony prominences of the femur and tibia, the anterior tibial translations corresponding to various settings were determined by customized image processing procedures. FINDINGS: In the electrical stimulation sessions, the knee extensions with electrical stimulation feedback induced significantly (n=6, P<.05) less anterior tibial translation over the range of 20 to 50° when compared to those using the standard isokinetic shank restraint. Likewise, the knee extensions with an anti-shear device that blocks tibia displacement mechanically also induced significantly (n=6, P<.05) less anterior tibial translation, but over a different range of knee extension (30 to 70°). INTERPRETATION: Despite the fact that both the electrical stimulator and the anti-shear device assisted in reducing anterior tibial translation, the tendency of the curves generated with the functional electrical stimulation was generally more similar to those generated when using the standard isokinetic shank restraint.


Assuntos
Ligamento Cruzado Anterior/fisiologia , Artralgia/fisiopatologia , Estimulação Elétrica , Articulação do Joelho/fisiologia , Tíbia/fisiologia , Adulto , Ligamento Cruzado Anterior/fisiopatologia , Artralgia/reabilitação , Exercício Físico/fisiologia , Voluntários Saudáveis , Humanos , Articulação do Joelho/fisiopatologia , Masculino , Movimento/fisiologia , Amplitude de Movimento Articular , Adulto Jovem
18.
Mitochondrion ; 13(2): 143-52, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23354120

RESUMO

Yeast Coq5p is required for the biosynthesis of coenzyme Q6 (CoQ6), but its human homolog has not been studied. We purified soluble recombinant human COQ5 protein under native conditions and generated an antibody recognizing both precursor and mature forms of COQ5. Mitochondrial localization of the mature form in 143B cells was demonstrated with this antibody. Moreover, a chemical uncoupler in a dose that suppressed CoQ10 levels downregulated the mature form but augmented the precursor form of COQ5. The results that knockdown of the COQ5 gene reduced CoQ10 levels further indicated the critical role of COQ5 in the biosynthesis of CoQ10.


Assuntos
Metiltransferases/análise , Mitocôndrias/química , Proteínas Mitocondriais/análise , Ubiquinona/análogos & derivados , Linhagem Celular , Humanos , Metiltransferases/metabolismo , Mitocôndrias/enzimologia , Proteínas Mitocondriais/metabolismo , Ubiquinona/biossíntese
19.
Diabetes Care ; 36(2): 369-75, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23043163

RESUMO

OBJECTIVE: Preclinical data suggest that peroxisome proliferator-activated receptor γ (PPARγ) agonists have antineoplastic effects in colorectal cancer. We aimed to assess the association between the use of synthetic PPARγ agonists, represented by thiazolidinediones (TZDs), and the risk of developing colorectal cancer. RESEARCH DESIGN AND METHODS: We conducted a nationwide, population-based, case-control study using the Taiwan National Health Insurance Research Database. Case subjects were defined as patients who were diagnosed with diabetes at least 365 days prior to a new diagnosis of colorectal cancer between 2000 and 2008. We randomly selected diabetic control subjects for each case subject, which were matched by sex, age, and the duration of diabetes. Among the 24,496 eligible case subjects and control subjects, we used conditional logistic regression to assess the risk of colorectal cancer in association with the use of TZDs. An additional analysis was conducted to assess the effects of concomitant use of TZDs and low-dose aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) on the risk of colorectal cancer. RESULTS: A decreased risk of colorectal cancer was observed in patients who had used TZDs compared with those who had never used TZDs (adjusted odds ratio 0.86 [95% CI 0.79-0.94]). Furthermore, the benefit of a decreased colorectal cancer risk was also found with concomitant use of TZDs and low-dose aspirin or NSAIDs. CONCLUSIONS: The use of TZDs may be associated with a decreased risk of colorectal cancer in patients with diabetes. Further studies are warranted to confirm our findings.


Assuntos
Neoplasias Colorretais/induzido quimicamente , Diabetes Mellitus Tipo 2/tratamento farmacológico , Tiazolidinedionas/efeitos adversos , Tiazolidinedionas/uso terapêutico , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Sensors (Basel) ; 12(7): 8987-9005, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23012529

RESUMO

A major cause of high energy consumption for air conditioning in indoor spaces is the thermal storage characteristics of a building's envelope concrete material; therefore, the physiological signals (temperature and humidity) within concrete structures are an important reference for building energy management. The current approach to measuring temperature and humidity within concrete structures (i.e., thermocouples and fiber optics) is limited by problems of wiring requirements, discontinuous monitoring, and high costs. This study uses radio frequency integrated circuits (RFIC) combined with temperature and humidity sensors (T/H sensors) for the design of a smart temperature and humidity information material (STHIM) that automatically, regularly, and continuously converts temperature and humidity signals within concrete and transmits them by radio frequency (RF) to the Building Physiology Information System (BPIS). This provides a new approach to measurement that incorporates direct measurement, wireless communication, and real-time continuous monitoring to assist building designers and users in making energy management decisions and judgments.

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