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1.
Am J Physiol Lung Cell Mol Physiol ; 324(5): L639-L651, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36648147

RESUMO

Idiopathic pulmonary fibrosis is increasingly associated with nerve-driven processes and endogenous innate immune ligands such as mitochondrial DNA (mtDNA). Interestingly, a connection between these entities has not been explored. Here, we report that noradrenaline (NA) derived from the lung's adrenergic nerve supply drives α-smooth muscle actin (αSMA)-expressing fibroblast accumulation via mechanisms involving α1 adrenoreceptors and mtDNA. Using the bleomycin model, we compared ablation of the lung's adrenergic nerve supply with surgical adrenal resection and found that NA derived from local but not adrenal sources contributes to experimentally induced lung fibrosis and the emergence of an αSMA+ve fibroblast population expressing adrenoreceptor α-1D (ADRA1D). Therapeutic delivery of the α1 adrenoreceptor antagonist terazosin reversed these changes and suppressed extracellular mtDNA accumulation. Cultured normal human lung fibroblasts displayed α1 adrenoreceptors and in response to costimulation with TGFß1 and NA adopted ACTA2 expression and extracellular mtDNA release. These findings were opposed by terazosin. Evaluation of a previously studied IPF cohort revealed that patients prescribed α1 adrenoreceptor antagonists for nonpulmonary indications demonstrated improved survival and reduced concentrations of plasma mtDNA. Our observations link nerve-derived NA, α1 adrenoreceptors, extracellular mtDNA, and lung fibrogenesis in mouse models, cultured cells, and humans with IPF. Further study of this neuroinnate connection may yield new avenues for investigation in the clinical and basic science realms.


Assuntos
DNA Mitocondrial , Fibrose Pulmonar Idiopática , Camundongos , Animais , Humanos , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/metabolismo , Transdução de Sinais , Fibroblastos/metabolismo , Bleomicina/farmacologia , Adrenérgicos/metabolismo , Adrenérgicos/farmacologia
2.
Arthritis Rheumatol ; 72(11): 1905-1915, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32602227

RESUMO

OBJECTIVE: Systemic sclerosis-associated interstitial lung disease (SSc-ILD) is characterized by variable clinical outcomes, activation of innate immune pattern-recognition receptors (PRRs), and accumulation of α-smooth muscle actin (α-SMA)-expressing myofibroblasts. The aim of this study was to identify an association between these entities and mitochondrial DNA (mtDNA), an endogenous ligand for the intracellular DNA-sensing PRRs Toll-like receptor 9 (TLR-9) and cyclic GMP-AMP synthase/stimulator of interferon genes (cGAS/STING), which has yet to be determined. METHODS: Human lung fibroblasts (HLFs) from normal donors and SSc-ILD explants were treated with synthetic CpG DNA and assayed for α-SMA expression and extracellular mtDNA using quantitative polymerase chain reaction for the human MT-ATP6 gene. Plasma MT-ATP6 concentrations were evaluated in 2 independent SSc-ILD cohorts and demographically matched controls. The ability of SSc-ILD and control plasma to induce TLR-9 and cGAS/STING activation was evaluated with commercially available HEK 293 reporter cells. Plasma concentrations of type I interferons (IFNs), interleukin-6 (IL-6), and oxidized DNA were measured using electrochemiluminescence and enzyme-linked immunosorbent assay-based methods. Extracellular vesicles (EVs) precipitated from plasma were evaluated for MT-ATP6 concentrations and proteomics via liquid chromatography mass spectrometry. RESULTS: Normal HLFs and SSc-ILD fibroblasts developed increased α-SMA expression and MT-ATP6 release following CpG stimulation. Plasma mtDNA concentrations were increased in the 2 SSc-ILD cohorts, reflective of ventilatory decline, and were positively associated with both TLR-9 and cGAS/STING activation as well as type I IFN and IL-6 expression. Plasma mtDNA was not oxidized and was conveyed by EVs displaying a proteomics profile consistent with a multicellular origin. CONCLUSION: These findings demonstrate a previously unrecognized connection between EV-encapsulated mtDNA, clinical outcomes, and intracellular DNA-sensing PRR activation in SSc-ILD. Further study of these interactions could catalyze novel mechanistic and therapeutic insights into SSc-ILD and related disorders.


Assuntos
DNA Mitocondrial/sangue , Doenças Pulmonares Intersticiais/sangue , Escleroderma Sistêmico/sangue , Actinas/metabolismo , Citocinas/metabolismo , Progressão da Doença , Feminino , Fibroblastos/metabolismo , Células HEK293 , Humanos , Doenças Pulmonares Intersticiais/etiologia , Masculino , Escleroderma Sistêmico/complicações
3.
J Healthc Eng ; 2019: 4938063, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30886685

RESUMO

To meet the need for "standard" testing system for wearable blood pressure sensors, this study intends to develop a new radial pulsation simulator that can generate age-dependent reference radial artery pressure waveforms reflecting the physiological characteristics of human cardiovascular system. To closely duplicate a human cardiovascular system, the proposed simulator consists of a left ventricle simulation module, an aorta simulation module, a peripheral resistance simulation module, and a positive/negative pressure control reservoir module. Simulating physiologies of blood pressure, the compliance chamber in the simulator can control arterial stiffness to produce age-dependent pressure waveforms. The augmentation index was used to assess the pressure waveforms generated by the simulator. The test results show that the simulator can generate and control radial pressure waveforms similar to human pulse signals consisting of early systolic pressure, late systolic pressure, and dicrotic notch. Furthermore, the simulator's left ventricular pressure-volume loop results demonstrate that the simulator exhibits mechanical characteristics of the human cardiovascular system. The proposed device can be effectively used as a "standard" radial artery pressure simulator to calibrate the wearable sensor's measurement characteristics and to develop more advanced sensors. The simulator is intended to serve as a platform for the development, performance verification, and calibration of wearable blood pressure sensors. It will contribute to the advancement of the wearable blood pressure sensor technology, which enables real-time monitoring of users' radial artery pressure waveforms and eventually predicting cardiovascular diseases.


Assuntos
Determinação da Pressão Arterial/instrumentação , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Modelos Cardiovasculares , Artéria Radial/fisiologia , Adulto , Simulação por Computador , Desenho de Equipamento , Humanos , Pessoa de Meia-Idade , Pulso Arterial/instrumentação , Processamento de Sinais Assistido por Computador , Adulto Jovem
4.
Biomed Eng Online ; 18(1): 1, 2019 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-30602383

RESUMO

BACKGROUND: There exists a growing need for a cost-effective, reliable, and portable pulsation simulator that can generate a wide variety of pulses depending on age and cardiovascular disease. For constructing compact pulsation simulator, this study proposes to use a pneumatic actuator based on cam-follower mechanism controlled by a DC motor. The simulator is intended to generate pulse waveforms for a range of pulse pressures and heart beats that are realistic to human blood pulsations. METHODS: This study first performed in vivo testing of a healthy young man to collect his pulse waveforms using a robotic tonometry system (RTS). Based on the collected data a representative human radial pulse waveform is obtained by conducting a mathematical analysis. This standard pulse waveform is then used to design the cam profile. Upon fabrication of the cam, the pulsatile simulator, consisting of the pulse pressure generating component, pressure and heart rate adjusting units, and the real-time pulse display, is constructed. Using the RTS, a series of testing was performed on the prototype to collect its pulse waveforms by varying the pressure levels and heart rates. Followed by the testing, the pulse waveforms generated by the prototype are compared with the representative, in vivo, pulse waveform. RESULTS: The radial Augmentation Index analysis results show that the percent error between the simulator data and human pulse profiles is sufficiently small, indicating that the first two peak pressures agree well. Moreover, the phase analysis results show that the phase delay errors between the pulse waveforms of the prototype and the representative waveform are adequately small, confirming that the prototype simulator is capable of simulating realistic human pulse waveforms. CONCLUSIONS: This study demonstrated that a very accurate radial pressure waveform can be reproduced using the cam-based simulator. It can be concluded that the same testing and design methods can be used to generate pulse waveforms for other age groups or any target pulse waveforms. Such a simulator can make a contribution to the research efforts, such as development of wearable pressure sensors, standardization of pulse diagnosis in oriental medicine, and training medical professionals for pulse diagnosis techniques.


Assuntos
Engenharia Biomédica/instrumentação , Pressão Sanguínea/fisiologia , Frequência Cardíaca , Artéria Radial/fisiologia , Engenharia Biomédica/métodos , Doenças Cardiovasculares/fisiopatologia , Simulação por Computador , Desenho de Equipamento , Análise de Fourier , Humanos , Manometria , Pressão , Pulso Arterial , Robótica , Processamento de Sinais Assistido por Computador , Adulto Jovem
5.
Rev Sci Instrum ; 82(3): 035112, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21456794

RESUMO

It is becoming more important to measure the pressure in high temperature environments in many industrial fields. However, there is no appropriate evaluation system and compensation method for high temperature pressure sensors since most pressure standards have been established at room temperature. In order to evaluate the high temperature pressure sensors used in harsh environments, such as high temperatures above 250 °C, a specialized system has been constructed and evaluated in this study. The pressure standard established at room temperature is connected to a high temperature pressure sensor through a chiller. The sensor can be evaluated in conditions of changing standard pressures at constant temperatures and of changing temperatures at constant pressures. According to the evaluation conditions, two compensation methods are proposed to eliminate deviation due to sensitivity changes and nonlinear behaviors except thermal hysteresis.

6.
Evid Based Complement Alternat Med ; 6 Suppl 1: 93-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19745017

RESUMO

The usefulness of constitutional diagnoses based on skin measurements has been established in oriental medicine. However, it is very difficult to standardize traditional diagnosis methods. According to Sasang constitutional medicine, humans can be distinguished based on properties of the skin, including its texture, roughness, hardness and elasticity. The elasticity of the skin was previously used to distinguish between people with Tae-eumin (TE) and Soeumin (SE) constitutions. The present study designed a system that uses a compression method to measure the elasticity of hand skin and evaluated its measurement repeatability. The proposed system was used to compare the skin elasticity between SE and TE subjects, which produced a measurement repeatability error of <3%. The proposed system is suitable for use as a quantitative constitution diagnosis method for distinguishing between TE and SE subjects with an acceptable level of uncertainty.

7.
J Nanosci Nanotechnol ; 8(10): 4999-5003, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19198378

RESUMO

We have studied growth behavior of carbon nanotubes (CNTs) on iron (Fe) catalyzed substrate using newly developed atmospheric pressure plasma enhanced chemical vapor deposition (AP-PECVD) system. To investigate the improved growth performance with simple equipment and process on large scale, a new AP-PECVD system containing different concept on downstream gas was designed and manufactured. As a catalyst, either sputtered or evaporated Fe thin film on SiO2/Si substrate was used and acetylene gas was used as a carbon source. We observed growth behavior of CNTs such as height, rate and density were strongly affected by plasma power. The maximum height of 427 microm and 267 microm was synthesized under RF plasma power of 30 W for 30 min and 40 W for 3 min, respectively. The growth rate dramatically increased to 6.27 times as plasma power increased from 30 to 40 W which opens the possibility the mass production of CNTs. By SEM and TEM observation, it was verified the grown CNTs was consists of mixture of single-wall and multi-wall CNTs. The graphitization ratio was measured to be 0.93, indicating that the graphitized CNTs forest was formed and relatively high purity of CNTs was synthesized, being useful for nano-composite materials to reinforce the strength. From our experiments, we can observe that the height and growth rate of CNTs is strong function of plasma power.

8.
Artigo em Inglês | MEDLINE | ID: mdl-19162967

RESUMO

The skin is an indispensible organ for human because it contributes to the metabolism using its own biochemical functions as well as it protects the human body from the exterior stimuli. Recently, the friction coefficient have been used as the decision index of the progress for the bacterial aliments in the field of the skin physiology and the importance of friction coefficient have been increased in the skin care market because of the needs of the well being times. In addition, the usage of friction coefficient is known to have the big discrimination ability in classification of human constitutions, which is utilized in the alternative medicine. In this study, we designed a system which used the multi axes load cell and hemi-circular probe and tried to measure the friction coefficient of hand skins repeatedly. Using this system, the relative repeatability error for the measurement of the friction coefficient was below 4 %. The coefficient is not concerned in curvatures of tips. Using this system, we will try to establish the standard for classification of constitutions.


Assuntos
Equipamentos e Provisões , Fricção , Mãos/fisiologia , Fenômenos Fisiológicos da Pele , Fenômenos Biomecânicos , Humanos
9.
Artigo em Inglês | MEDLINE | ID: mdl-19163409

RESUMO

Blood pressure is defined as the amount of force at unit area which the blood exerts on a wall of a blood vessel. The BP has a clinical importance as the basic index in the medical examination of patients. Especially, the percentage of the hypertensive is more than 15% in an adult population of Korea and hypertension is notorious as 'a silent killer' because it has no prior symptoms. The most important thing in the diagnosis, treatment and prognosis of hypertension is the accurate measurement of the BP. In this study, we developed the blood pressure simulator for the monitoring of oscillometric BP devices and compared this KRISS simulator with commercial simulators. Finally, we tested the commercial oscillometric BP devices (6 models from 5 manufacturers) using the KRISS simulator. The KRISS simulator has the repeatability error below 0.1% for the pressure generation and we expected to develop the BP simulator for Korean by the collection of clinical data from Koreans.


Assuntos
Determinação da Pressão Arterial/métodos , Monitorização Ambulatorial da Pressão Arterial/instrumentação , Algoritmos , Pressão Sanguínea , Determinação da Pressão Arterial/instrumentação , Calibragem , Simulação por Computador , Desenho de Equipamento , Humanos , Hipertensão/diagnóstico , Oscilometria , Reprodutibilidade dos Testes , Software
10.
Croat Med J ; 46(4): 619-21, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16100766

RESUMO

AIM: To develop a method for enhanced polymerase chain reaction (PCR) product detection. METHODS: During the PCR, the double-stranded product is generated with fluorescent dye on one strand, and biotin on the other strand. The product is captured on the streptavidin-coated plates with high efficiency (IPCRp). Washing of the all unamplified compounds, including dye-labeled unincorporated primers, follows the PCR. The targeted dye-labeled PCR product is released by denaturation and loaded on the detection platform. RESULTS: After the application of the IPCRp, the resulting product is highly concentrated targeted dye-labeled single-stranded DNA, free of the unincorporated primers and other PCR artifacts. The strength of the signal of the IPCRp product on detection platform is two- to five-fold higher than the strength of the signal of the conventional PCR product. CONCLUSION: The IPCRp procedure can be accomplished in less than 20 minutes. Efficient isolation of the PCR products has two steps, washing and denaturation. It can increase the yield of targeted PCR product and increase the sensitivity of the detection platform.


Assuntos
DNA/genética , Reação em Cadeia da Polimerase/métodos , DNA/isolamento & purificação , Genótipo , Humanos , Reação em Cadeia da Polimerase/normas , Estados Unidos
11.
Anal Chem ; 77(7): 2043-9, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15801736

RESUMO

We report a novel, real-time fluorogenic kinase assay. The peptide substrates are synthesized with a fluorescent dye and a hydrocarbon tail. The substrate self-assembles into micelles, increasing the local concentration of the dye and quenching its fluorescence. Upon phosphorylation, the fluorescence intensity increases 4-6-fold due to micelle reorganization. Both dynamic light scattering data and cryoelectron microscope images show that the size and the shape of the phosphopeptide micelles are significantly different from micelles of substrate peptide. The system provides a robust fluorescence increase in a real-time protein kinase assay. Unlike other fluorogenic systems, the fluorophore may be distant from the serine, threonine, or tyrosine that is phosphorylated. Assays for several kinases, including PKA, PKC, p38, MAPKAP K2, akt, Erk1, and src-family kinases, have been developed. IC(50) values of inhibitors for PKC betaII determined with this technology are consistent with published values. The utility of this assay to high-throughput screening was demonstrated with Sigma's LOPAC library, a collection of 640 compounds with known biological activities, and satisfactory results were obtained.


Assuntos
Técnicas de Química Analítica/métodos , Proteínas Quinases/análise , Trifosfato de Adenosina/metabolismo , Técnicas de Química Combinatória , Microscopia Crioeletrônica , Avaliação Pré-Clínica de Medicamentos/métodos , Fluorescência , Micelas , Fosforilação , Proteína Quinase C/análise , Proteína Quinase C/metabolismo , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Reprodutibilidade dos Testes , Espalhamento de Radiação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Especificidade por Substrato , Titulometria
12.
Can Vet J ; 40(7): 506-8, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10416074

RESUMO

Bovine listeriosis is a sporadie bacterial infection most commonly manifested by encephalitis or meningoencephalitis in adult animals. Cattle fed poorly fermented haylage or corn silage are at increased risk. Mortality is high without early antibiotic and supportive therapy. Listeria monocytogenes can affect many species and is a public health concern.


Assuntos
Doenças dos Bovinos/diagnóstico , Listeriose/veterinária , Ração Animal , Animais , Bovinos , Feminino , Listeria monocytogenes/isolamento & purificação , Listeriose/diagnóstico
13.
Percept Mot Skills ; 85(2): 531-46, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9347539

RESUMO

A review of studies comparing the WISC-III to other measures of intelligence and achievement indicates the revision is continuing to meet the standards established by its predecessor, the WISC-R. Correlations are substantial, both for measures of ability and achievement; however, compared to the WISC-R, the WISC-III Full Scale IQ tends to be about six points lower, probably reflecting the "Flynn effect" (1984). As a consequence, eligibility for programs in special education may be negatively affected.


Assuntos
Escalas de Wechsler/estatística & dados numéricos , Humanos , Deficiência Intelectual/classificação , Deficiência Intelectual/diagnóstico , Psicometria , Reprodutibilidade dos Testes , Escalas de Wechsler/normas
14.
J Pediatr ; 97(5): 721-7, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7431163

RESUMO

Three hundred forty-four patients under 18 years of age with severe closed head injuries, comatose over 24 hours, were followed prospectively for a minimum of one year. Motor vehicles were involved in 82% of the injuries. Seventy-three percent of the patients regained independence in ambulation and self-care, 10% remained partially dependent in self-care and achieved only limited ambulation, 9% regained consciousness but were totally dependent, and 8% remained comatose. A favorable prognosis for recovery of motor function can be made if the duration of coma is less than three months. Complications of prolonged hypertension, ventricular enlargement, and seizures significantly decrease the probability of achieving physical independence. Although mortality following severe head injury is decreasing, neurologic sequelae in the survivors are statistically unchanged since 1970. Improved neurosurgical management in recent years has not increased the percentage of severely disabled survivors.


Assuntos
Lesões Encefálicas/reabilitação , Traumatismos Craniocerebrais/reabilitação , Acidentes de Trânsito , Adolescente , Edema Encefálico/etiologia , Lesões Encefálicas/complicações , Lesões Encefálicas/diagnóstico por imagem , Criança , Pré-Escolar , Coma/complicações , Traumatismos Craniocerebrais/complicações , Traumatismos Craniocerebrais/diagnóstico por imagem , Feminino , Humanos , Hipertensão/etiologia , Lactente , Masculino , Transtornos dos Movimentos/etiologia , Prognóstico , Convulsões/etiologia , Autocuidado , Tomografia Computadorizada por Raios X
15.
Br J Dermatol ; 100(3): 267-76, 1979 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-155468

RESUMO

Various concentrations of vitamin A acid were applied to experimentally induced comedones. All concentrations produced non-cohesive hyperkeratinization, which loosened the cohesive horny mass induced by oleic acid and expelled it from the follicle within 7 days. The highest concentration (0.1%) produced the greatest degree of non-cohesive desquamation in the shortest time. In follicles treated with the acid, the cell membrane of horny cells was thin and ruptured easily to produce a non-cohesive debris. Desmosomes were scarce and desmosomal bodies (fusiform electron-dense bodies) and tight junctions between horny cells were not seen in follicles treated with the acid. The acid also produced hyperplasia of the epithelial wall and an apparently increased mitotic rate. A 0.025% concentration of the acid increased the number of membrane coating granules by about 70% in all regions of the follicle.


Assuntos
Acne Vulgar/tratamento farmacológico , Tretinoína/uso terapêutico , Vitamina A/análogos & derivados , Acne Vulgar/induzido quimicamente , Acne Vulgar/patologia , Animais , Membrana Celular/ultraestrutura , Desmossomos/ultraestrutura , Masculino , Microscopia Eletrônica , Coelhos , Pele/ultraestrutura
16.
Br J Dermatol ; 99(4): 387-94, 1978 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-152114

RESUMO

Membrane coating granules (MCGs) may be required for normal keratinization. Comedone formation is associated with abnormal keratinization, and so the MCGs in sebacaous follicles were counted during experimental comedogenesis in the rabbit. During induced comedo formation with 50% oleic acid in paraffin oil, the numbers of MCGs decreased significantly; first, at the epidermis and mouth of the follicle and then later, at the follicular canal and common sebaceous duct. The maximum decrease of about 40% was reached by the 6th day in these regions. Throughout the treatment, the MCG count in the individual sebaceous ducts remained fairly constant.


Assuntos
Acne Vulgar/patologia , Cabelo/ultraestrutura , Animais , Membrana Celular/ultraestrutura , Grânulos Citoplasmáticos/ultraestrutura , Queratinas , Microscopia Eletrônica , Coelhos
17.
Br J Dermatol ; 97(6): 609-15, 1977 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-146509

RESUMO

Cohesion between horny cells was studied in experimentally induced comedones, from the rabbit's external ear canal. It occurred in two different ways: initially, by the persistence of desmosones and desmonosmal bodies (fusiform electron dense bodies), which loosely held the horny cells together; later, and to a lesser extent, by tight junctions, which tightly bound the horny cells together. A gradual decrease in the numbers of membrane coating granules was observed.


Assuntos
Acne Vulgar/patologia , Pele/ultraestrutura , Animais , Adesão Celular , Desmossomos/ultraestrutura , Junções Intercelulares/ultraestrutura , Masculino , Microscopia Eletrônica , Coelhos
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