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1.
Artigo em Inglês | MEDLINE | ID: mdl-31995476

RESUMO

Generating computer graphics (CG) rendered synthetic images has been widely used to create simulation environments for robotics/autonomous driving and generate labeled data. Yet, the problem of training models purely with synthetic data remains challenging due to the considerable domain gaps caused by current limitations on rendering. In this paper, we propose a simple yet effective domain adaptation framework towards closing such gap at image level. Unlike many GAN-based approaches, our method aims to match the covariance of the universal feature embeddings across domains, making the adaptation a fast, convenient "on-the-fly" step and avoiding the need for potentially difficult GAN trainings. To align domains more precisely, we further propose a conditional covariance matching framework which iteratively estimates semantic segmentation regions and conditionally matches the class-wise feature covariance given the segmentation regions. We demonstrate that both tasks can mutually refine and considerably improve each other, leading to state-of-the-art domain adaptation results. Extensive experiments under multiple synthetic-to-real settings show that our approach exceeds the performance of latest domain adaptation approaches. In addition, we offer a quantitative analysis where our framework shows considerable reduction in Frechet Inception distance between source and target domains, demonstrating the effectiveness of this work in bridging the synthetic-to-real domain gap.

2.
IEEE Trans Pattern Anal Mach Intell ; 42(6): 1408-1423, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-30676944

RESUMO

We investigate two crucial and closely-related aspects of CNNs for optical flow estimation: models and training. First, we design a compact but effective CNN model, called PWC-Net, according to simple and well-established principles: pyramidal processing, warping, and cost volume processing. PWC-Net is 17 times smaller in size, 2 times faster in inference, and 11 percent more accurate on Sintel final than the recent FlowNet2 model. It is the winning entry in the optical flow competition of the robust vision challenge. Next, we experimentally analyze the sources of our performance gains. In particular, we use the same training procedure for PWC-Net to retrain FlowNetC, a sub-network of FlowNet2. The retrained FlowNetC is 56 percent more accurate on Sintel final than the previously trained one and even 5 percent more accurate than the FlowNet2 model. We further improve the training procedure and increase the accuracy of PWC-Net on Sintel by 10 percent and on KITTI 2012 and 2015 by 20 percent. Our newly trained model parameters and training protocols are available on https://github.com/NVlabs/PWC-Net.

3.
J Formos Med Assoc ; 119(1 Pt 2): 345-349, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31255418

RESUMO

BACKGROUND/PURPOSE: Thyroid disorders are common in children with Down syndrome (DS), however, such data have rarely been reported in Taiwanese children. This study presents our experience with the management of these children. METHODS: Between 2006 and 2016, 51 children (31 boys and 20 girls) with DS were enrolled. Thyroid function was evaluated and natural course of thyroid status were analyzed. RESULTS: Of 51 patients with DS, 2 had congenital hypothyroidism due to dyshormonogenesis. Of the remaining 49 patients, 30 (61%) had euthyroidism (EuT), and 19 (39%) had subclinical hypothyroidism (SH). Eighteen (37%) had detectable thyroid antibodies. It occurred at any age and the incidence was not affected by sex. The mean follow-up duration for 39 DS children was 3.8 ± 2.4 years. Of the 26 children who had EuT at enrollment and were followed up, 22 remained EuT, 2 developed SH, 1 developed overt hypothyroidism, and 1 developed overt hyperthyroidism. Of the 13 patients with SH who were followed up, 1 was treated for high thyroid-stimulating hormone levels, 8 became EuT, and 4 maintained SH status. Children with DS and persistent SH had significantly higher maximum thyroid-stimulating hormone levels during follow-up than did those with transient SH. Fluctuation in thyroid status during follow-up was not uncommon in children with DS. CONCLUSION: The prevalence of thyroid disorders is higher in Taiwanese children with DS than in the general population. Because symptoms of hypothyroidism overlap those inherent to DS, regular follow-up of thyroid function in children with DS is indicated.


Assuntos
Síndrome de Down/complicações , Hipertireoidismo/complicações , Hipotireoidismo/complicações , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Masculino , Prevalência , Taiwan
4.
Huan Jing Ke Xue ; 40(8): 3650-3659, 2019 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854772

RESUMO

The direct discharge of wastewater from pig farms can restrict wetland plant growth meaning that constructed wetlands (CWs) have generally low treatment efficiency. The treatment of farming wastewater using pre-ecological treatment technologies can be used to ensure that effluent concentrations reach the tolerable limits of wetland plants. This study focused on the efficient use of crop straw for reducing the pollution load of swine wastewater. Using field-scale pilot tests, wheat straw, straw, and corn stalk were used as test biological matrix pool fillers to treat the farming wastewater. Continuous intake of wastewater and a hydraulic retention time of 7 days was adopted. When the average concentrations of COD, TN, NH4+-N, NO3--N, and TP in the influent were 1652.83 mg·L-1, 371.31 mg·L-1, 303.51 mg·L-1, 0.67 mg·L-1, and 65.22 mg·L-1, respectively, wheat straw had the greatest removal effect on COD, TN, and TP, achieving a removal rate of 32.1%, 40.9%, and 33.3%, respectively. The removal efficiency of straw on NH4+-N was highest, reaching 43.4%. After 180 days, the lignin, cellulose, and hemicellulose of the three matrix materials were not completely decomposed. The degradation rate of lignin was lower than for cellulose and hemicellulose; the degradation of lignin and cellulose in the straw was fastest; and the degradation hemicellulose in wheat straw was fastest. The results show that wheat straw and straw offer a higher efficiency treatment for swine wastewater than corn stalk, and the suggested replacement cycle period is five months. These results provide initial data to support the application of biological matrix materials in the treatment of swine wastewater.

5.
Shanghai Kou Qiang Yi Xue ; 27(3): 285-288, 2018 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-30411125

RESUMO

PURPOSE: To assess the impact of oral health promotion project on periodontal condition and life quality of the elderly in long-term care institutions. METHODS: Elder people from 5 nursing homes in Wuhan city were selected and assigned to either the experimental group or the control group by random cluster grouping method. A six-month oral health promotion project was provided to the experimental group. The changes of geriatric oral health assessment index (GOHAI), oral hygiene index-simplified (OHI-S), gingival index (GI), bleeding on probing (BOP) and probing depth (PD) were compared with student's t test and repetitive measure analysis of variance using SPSS21.0 software package. RESULTS: A total of 322 subjects completed the study for 6 months, with 144 from the experimental group and 178 from the control group. No significant difference was observed between the two groups in social demographic characteristics, GOHAI scores, OHI-S, GI, BOP and PD at baseline(P>0.05). Greater improvements were observed in GOHAI scores, OHI-S, GI and BOP in the experimental group than the control group after interventions (P<0.05). CONCLUSIONS: Oral health promotion project can improve the elderly's oral health-related quality of life and periodontal condition.


Assuntos
Promoção da Saúde , Saúde Bucal , Qualidade de Vida , Idoso , Humanos , Assistência de Longa Duração , Doenças Periodontais , Índice Periodontal
6.
Shanghai Kou Qiang Yi Xue ; 27(2): 181-184, 2018 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-30146646

RESUMO

PURPOSE: To assess the impact of comprehensive health education on oral care knowledge, attitude and practice(KAP) of the elderly in the long-term care institutions and to provide references for oral health education among the elder people. METHODS: Elder people from 2 nursing centers in Wuhan were selected. The follow-up period was 6 months. Questionnaires were used to collect social-demographic characteristics and oral care KAP data at baseline, the third month and the sixth month, respectively. Comprehensive health education, toothpaste and toothbrushes were provided at baseline and the third month. The changes of oral care KAP were observed before and after interventions. SPSS21.0 software package was used for statistical analysis. RESULTS: A total of 144 subjects with a mean age of (72.43±9.41) years completed the study after 6 months. At baseline, the KAP scores were (28.57±19.19), (70.66±21.99) and (39.86±24.18), respectively. At the sixth month, the KAP scores were (91.06±9.55), (95.31±10.23) and (90.00±13.38), respectively and significant improvements were observed (F=913.714, P<0.001; F=114.042, P<0.001; F=349.887, P<0.001). Oral care knowledge and attitude, knowledge and practice, attitude and practice were positively correlated(ß=0.173, P=0.038; ß=0.269, P=0.001; ß=0.197, P=0.018). Social-demographic characteristics had no significant effect on KAP scores (P>0.05). CONCLUSIONS: Long-term care institutions should strengthen oral health education and improve oral care KAP, oral health status and oral health-related quality of life of the elder people.


Assuntos
Educação em Saúde Bucal , Assistência de Longa Duração , Saúde Bucal , Idoso , Idoso de 80 Anos ou mais , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Qualidade de Vida
7.
Opt Express ; 26(2): 2065-2078, 2018 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-29401931

RESUMO

Freeform surfaces have become increasingly widespread in the optical systems for enhanced performance and compact lightweight packaging. The geometrical complexity and high precision requirements of optical freeform surfaces for various functional optical applications, has posed great challenges in the design, precision machining, and measurement of these surfaces. This paper presents a model-based self-optimization approach for precision machining and measurement of optical freeform surfaces in the computer controlled bonnet polishing (CCBP) process. To realize the technical feasibility, the process parameters and motion control are accurately performed through modelling and simulation of machining processes, error compensation, and on-machine metrology.

8.
Cell Physiol Biochem ; 42(5): 1802-1811, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28750371

RESUMO

BACKGROUND/AIMS: Endothelin-1 is implicated in the pathogenesis of hypertension, but the underlying mechanisms remained elusive. Our previous study found that inhibition of mitochondrial fission of smooth muscle cells suppressed phenylephrine- and high K+-induced artery constriction. Here, we studied the effects of mitochondrial fission inhibitors on endothelin-1-induced vasoconstriction. METHODS: The tension of rat mesenteric arteries and thoracic aorta was measured by using a multi-wire myograph system. Mitochondrial morphology of aortic smooth muscle cells was observed by using transmission electron microscopy. RESULTS: Dynamin-related protein-1 selective inhibitor mdivi-1 relaxed endothelin-1-induced constriction, and mdivi-1 pre-treatment prevented endothelin-1-induced constriction of rat mesenteric arteries with intact and denuded endothelium. Mdivi-1 had a similar inhibitory effect on rat thoracic aorta. Another mitochondrial fission inhibitor dynasore showed similar effects as mdivi-1 in rat mesenteric arteries. Mdivi-1 inhibited endothelin-1-induced increase of mitochondrial fission in smooth muscle cells of rat aorta. Rho-associated protein kinase inhibitor Y-27632 which relaxed endothelin-1-induced vasoconstriction inhibited endothelin-1-induced mitochondrial fission in smooth muscle cells of rat aorta. CONCLUSION: Endothelin-1 increases mitochondrial fission in vascular smooth muscle cells, and mitochondrial fission inhibitors suppress endothelin-1-induced vasoconstriction.


Assuntos
Aorta Torácica/fisiologia , Endotelina-1/metabolismo , Artérias Mesentéricas/fisiologia , Dinâmica Mitocondrial/efeitos dos fármacos , Quinazolinonas/farmacologia , Amidas/farmacologia , Animais , Aorta Torácica/citologia , Aorta Torácica/efeitos dos fármacos , Dinaminas/antagonistas & inibidores , Dinaminas/metabolismo , Endotelina-1/antagonistas & inibidores , Hidrazonas/farmacologia , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Mitocôndrias/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Vasoconstrição/efeitos dos fármacos
9.
BMC Pediatr ; 17(1): 139, 2017 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-28587647

RESUMO

BACKGROUND: Kawasaki disease (KD) is an acute systemic vasculitis that occurs in children and may lead to cardiovascular morbidity and mortality. Progressive coronary dilatation for at least 2 months is associated with worse late coronary outcomes in patients with KD having medium or giant aneurysms. However, the risk factors and occurrence of progressive coronary dilatation in patients with KD but without medium or giant aneurysms have been insufficiently explored. METHODS: We retrospectively enrolled 169 patients with KD from a tertiary medical center in Taiwan during 2009-2013. Medical records of all patients were reviewed. Echocardiography was performed during the acute KD phase and at 3-4 weeks, 6-8 weeks, 6 months, and 12 months after KD onset. Progressive coronary dilatation was defined as the progressive enlargement of coronary arteries on three consecutive echocardiograms. Logistic regression analysis was conducted to evaluate the potential risk factors for coronary aneurysms and progressive coronary dilatation. RESULTS: Of a total of 169 patients with KD, 31 (18.3%) had maximal coronary Z-scores of ≥ + 2.5 during the acute KD phase, 16 (9.5%; male/female: 9/7) had coronary aneurysms at 1 month after KD onset, and 5 (3.0%) satisfied the definition of progressive coronary dilatation. Multivariate logistic regression analysis revealed that an initial maximal coronary Z-score of ≥ + 2.5 [odds ratio (OR): 5.24, 95% confidence interval (CI): 1.31-21.3, P = 0.020] and hypoalbuminemia (OR: 4.83, 95% CI: 1.11-20.9, P = 0.035) were independent risk factors for coronary aneurysms and were significantly associated with progressive coronary dilatation. However, the association between intravenous immunoglobulin unresponsiveness and the development of coronary aneurysms at 1 month after KD onset didn't reach the level of significance (P = 0.058). CONCLUSIONS: In the present study, 3% (5/169) of patients with KD had progressive coronary dilatation, which was associated with persistent coronary aneurysms at 1 year after KD onset. Initial coronary dilatation and hypoalbuminemia were independently associated with the occurrence of progressive coronary dilatation. Therefore, such patients may require intensive cardiac monitoring and adjuvant therapies apart from immunoglobulin therapies.


Assuntos
Aneurisma Coronário/etiologia , Vasos Coronários/patologia , Síndrome de Linfonodos Mucocutâneos/complicações , Pré-Escolar , Aneurisma Coronário/diagnóstico por imagem , Aneurisma Coronário/patologia , Vasos Coronários/diagnóstico por imagem , Dilatação Patológica/diagnóstico por imagem , Dilatação Patológica/etiologia , Progressão da Doença , Ecocardiografia , Feminino , Seguimentos , Humanos , Lactente , Modelos Logísticos , Masculino , Síndrome de Linfonodos Mucocutâneos/patologia , Razão de Chances , Estudos Retrospectivos , Fatores de Risco
10.
Pharmacol Res ; 115: 78-86, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27872020

RESUMO

We previously demonstrated that the typical mitochondrial uncoupler carbonyl cyanide m-chlorophenylhydrazone (CCCP) inhibited artery constriction, but CCCP was used only as a pharmacological tool. Niclosamide is an anthelmintic drug approved by FDA. Niclosamide ethanolamine (NEN) is a salt form of niclosamide and has been demonstrated to uncouple mitochondrial oxidative phosphorylation. The aim of the present study was to elucidate the vasoactivity of NEN and the potential mechanisms. Isometric tension of rat mesenteric artery and thoracic aorta was recorded by using multi-wire myograph system. The protein levels were measured by using western blot techniques. Niclosamide ethanolamine (NEN) treatment relaxed phenylephrine (PE)- and high K+ (KPSS)-induced constriction, and pre-treatment with NEN inhibited PE- and KPSS-induced constriction of rat mesenteric arteries. In rat thoracic aorta, NEN also showed antagonism against PE- and KPSS-induced constriction. NEN induced increase of cellular ADP/ATP ratio in vascular smooth muscle cells (A10) and activated AMP-activated protein kinase (AMPK) in A10 cells and rat thoracic aorta. NEN-induced aorta relaxation was attenuated in AMPKα1 knockout (-/-) mice. SERCA inhibitors cyclopiazonic acid and thapsigargin, but not KATP channel blockers glibenclamide and 5-hydroxydecanoic acid, attenuated NEN-induced vasorelaxation in rat mesenteric arteries. NEN treatment increased cytosolic [Ca2+]i and depolarized mitochondrial membrane potential in vascular smooth muscle cells (A10). Niclosamide in non-salt form showed the similar vasoactivity as NEN in rat mesenteric arteries. Niclosamide ethanolamine inhibits artery constriction, indicating that it would be promising to be developed as an anti-hypertensive drug or it would induce vasodilation-related side effects when absorbed in vivo.


Assuntos
Aorta Torácica/efeitos dos fármacos , Etanolamina/farmacologia , Artérias Mesentéricas/efeitos dos fármacos , Niclosamida/farmacologia , Vasoconstrição/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Anti-Hipertensivos/farmacologia , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aorta Torácica/metabolismo , Canais KATP/antagonistas & inibidores , Masculino , Artérias Mesentéricas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Fenilefrina/farmacologia , Ratos , Ratos Sprague-Dawley , Doenças Vasculares/tratamento farmacológico , Doenças Vasculares/metabolismo , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia
11.
PLoS One ; 11(11): e0166109, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27829012

RESUMO

Management is an effective tool for increasing the productivity of Mongolian pine (Pinus sylvestris var. mongolica). This species has been widely planted in China, especially in sandy lands. However, optimization of management practices had not been fully explored. We established a system dynamic model to evaluate the effects of thinning and of manipulation of water supply on the productivity and population density of a Mongolian pine forest (17 scenarios in total). Different levels of thinning increased the mean biomass of Mongolian pine over no-management to a range from 202 to 256 t·ha-1. Increasing water supply decreased the mean biomass of Mongolian pine to a range from 176 to 199 t·ha-1. These results indicated that thinning at different levels may lead to an increase in biomass accumulation, while manipulating water supply may decrease biomass. Further, thinning appeared more effective than increasing water supply in efforts at maintaining high productivity of Mongolian pine forests. Moreover, the highest biomass occurred in a scenario with a thinning intensity of 30% in over-mature trees, indicating that this thinning intensity was the most effective choice for to the maintenance of the highest biomass in Mongolian pine forests. This study informs about the interactions between Mongolian pine and forest management, and provides guidelines for the practice of management of this forest type.


Assuntos
Agricultura Florestal/métodos , Pinus sylvestris/crescimento & desenvolvimento , Abastecimento de Água , Biomassa , China , Modelos Teóricos
12.
Br J Pharmacol ; 173(21): 3145-3158, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27534899

RESUMO

BACKGROUND AND PURPOSE: The effects and mechanisms of chemical mitochondrial uncouplers on vascular function have never been identified. Here, we characterized the effects of the typical mitochondrial uncoupler carbonyl cyanide m-chlorophenylhydrazone (CCCP) on vascular function in rat mesenteric arteries and aorta and elucidated the potential mechanisms. EXPERIMENTAL APPROACH: Isometric tension of mesenteric artery and thoracic aorta was recorded by using a multiwire myograph system. Protein levels were measured by western blot analyses. Cytosolic [Ca2+ ]i , mitochondrial ROS (mitoROS) and mitochondrial membrane potential of smooth muscle cells (A10) were measured by laser scanning confocal microscopy. KEY RESULTS: Acute treatment with CCCP relaxed phenylephrine (PE)- and high K+ (KPSS)-induced constriction of rat mesenteric arteries with intact and denuded endothelium. Pretreatment with CCCP prevented PE- and KPSS-induced constriction of rat mesenteric arteries with intact and denuded endothelium. Similarly, CCCP prevented PE- and KPSS-induced constriction of rat thoracic aorta. CCCP increased the cellular ADP/ATP ratio in vascular smooth muscle cells (A10) and activated AMPK in A10 cells and rat thoracic aorta tissues. CCCP-induced aorta relaxation was attenuated in AMPK α1 knockout (-/-) mice. SERCA inhibitors thapsigargin and cyclopiazonic acid (CPA) but not the KATP channel blocker glibenclamide partially inhibited CCCP-induced vasorelaxation in endothelium-denuded rat mesenteric arteries. CCCP increased cytosolic [Ca2+ ]i , mitoROS production and depolarized mitochondrial membrane potential in A10 cells. FCCP, the analogue of CCCP, had similar vasoactivity as CCCP in rat mesenteric arteries. CONCLUSIONS AND IMPLICATIONS: CCCP induces vasorelaxation by a mechanism that does not involve KATP channel activation in smooth muscle cells of arteries.


Assuntos
Artérias/citologia , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Mitocôndrias/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Desacopladores/farmacologia , Vasodilatação/efeitos dos fármacos , Animais , Artérias/efeitos dos fármacos , Carbonil Cianeto m-Clorofenil Hidrazona/química , Relação Dose-Resposta a Droga , Canais KATP/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Desacopladores/química
13.
Hypertension ; 68(5): 1245-1254, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27572148

RESUMO

Mitochondria are dynamic organelles and continuously undergo fission and fusion processes. Mitochondrial fission is involved in multiple physiological or pathological processes, but the role of mitochondrial fission of smooth muscle cells in artery constriction is unknown. The role of mitochondrial fission of smooth muscle cells in arterial function was investigated by measuring the tension of rat mesenteric arteries and thoracic aorta and by evaluating mitochondrial fission, mitochondrial reactive oxygen species, and cytosolic [Ca2+]i in rat vascular smooth muscle cells. Mitochondrial fission inhibitors mdivi-1 and dynasore antagonized phenylephrine- and high K+-induced constriction of rat mesenteric arteries. Mdivi-1 relaxed phenylephrine-induced constriction, and mdivi-1 pretreatment prevented phenylephrine-induced constriction in mice, rat aorta, and human mesenteric arteries. Phenylephrine- and high K+-induced increase of mitochondrial fission in smooth muscle cells of rat aorta and the increase was inhibited by mdivi-1. Mdivi-1 inhibited high K+-induced increases of mitochondrial fission, mitochondrial reactive oxygen species, and cytosolic [Ca2+]i in rat vascular smooth muscle cells. Prechelation of cytosolic Ca2+ prevented high K+-induced cytosolic [Ca2+]i increase, mitochondrial fission, and mitochondrial reactive oxygen species overproduction. Mitochondria-targeted antioxidant mito-TEMPO antagonized phenylephrine- and high K+-induced constriction of rat mesenteric arteries. Nitroglycerin and ROCK (Rho-associated protein kinase) inhibitor Y27632, the 2 vasodilators with different vasorelaxant mechanisms, relaxed high K+-induced vasoconstriction and inhibited high K+-induced mitochondrial fission. In conclusion, the mitochondrial fission of smooth muscle cells is involved in artery constriction.


Assuntos
Dinâmica Mitocondrial/efeitos dos fármacos , Músculo Liso Vascular/citologia , Quinazolinonas/farmacologia , Vasoconstrição/efeitos dos fármacos , Amidas/farmacologia , Análise de Variância , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Células Cultivadas , Interações Medicamentosas , Humanos , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/metabolismo , Modelos Animais , Células Musculares/citologia , Células Musculares/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Fenilefrina/farmacologia , Piridinas/farmacologia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Doenças Vasculares/tratamento farmacológico , Doenças Vasculares/fisiopatologia , Vasoconstrição/fisiologia , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia
14.
Eur J Pharmacol ; 774: 118-26, 2016 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-26851371

RESUMO

The bile acids (BAs) and their conjugates have vascular activities and the serum levels of BAs and their conjugates are increased in liver diseases. In the present study, we examined the in vitro vasoactivities of BAs conjugates taurochenodeoxycholate (TCDC) (5-80 µM), glycochenodeoxycholate (GCDC) (20-150 µM) and tauroursodeoxycholate (TUDC) (20-150 µM) in rat mesenteric arteries and thoracic aorta. The isometric tension of rat mesenteric arteries and thoracic aorta was recorded by using multi-wire myograph systems. TCDC induced significant concentration-dependent relaxation in endothelium-intact but not endothelium-denuded rat mesenteric arteries pre-contracted with phenylephrine (PE). TCDC also showed vasorelaxant effects on high K(+) induced contraction in rat mesenteric arteries. L-NAME treatment inhibited TCDC-induced relaxation in mesenteric arteries pre-contracted with PE. Acute treatment with TCDC increased protein expression of P-eNOS (ser1177) in human umbilical vein endothelial cells. GCDC dose-dependently relaxed PE-induced vasoconstriction in both endotheium-intact and endothelium-denuded rat mesenteric arteries, but GCDC showed no effect on high K(+)-induced vasoconstriction. Both GCDC and TCDC showed no apparent relaxation on PE and high K(+)-induced vasoconstriction in rat thoracic aorta. TUDC showed no effect on PE and high K(+)-induced vasoconstriction in rat mesenteric arteries and thoracic aorta. The study demonstrates that TCDC relaxes rat mesenteric arteries through activating eNOS. TCDC might be the major BAs conjugate for vasorelaxation in vivo.


Assuntos
Ácido Glicoquenodesoxicólico/farmacologia , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/fisiologia , Óxido Nítrico Sintase Tipo III/metabolismo , Ácido Tauroquenodesoxicólico/farmacologia , Vasodilatação/efeitos dos fármacos , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/fisiologia , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Masculino , Artérias Mesentéricas/enzimologia , Ratos , Ratos Sprague-Dawley
15.
Huan Jing Ke Xue ; 37(11): 4103-4109, 2016 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964658

RESUMO

VOCs emission of service station is one of the main sources of VOCs in Beijing. Uncontrolled emission factor (UEF) of refueling in China, US EPA, EEA respectively is 2.16, 1.31 and 1.00 times of CARB UEF (1008 mg·L-1). China's gasoline standards have changed in the last 20 years, and there is an urgent need to carry out the localization of gasoline refueling VOCs emission factor research. This paper compared test methods for refueling emission factors of European Union (EU) and California Air Resources Board (CARB) and found that the EU method was simpler and easier to operate than the CARB method, so we processed refueling VOCs emission factors test device in reference to EU test methods and chose a set of United States Stage Ⅱ vapor recovery system in Beijing service stations to carry out studies on VOCs emission factors. The results showed that: 1 For the fuel test tank, refueling vapor recovery efficiencies were 0.93 and 0.83 times of air to liquid volume ratio (A/L) of Stage Ⅱ respectively in winter and summer. Refueling emission factor in summer was greater than that in winter, and its recovery efficiency was lower than that in winter. 2 For the social vehicles, winter and summer refueling UEF respectively was (525±42) mg·L-1 and (963±174) mg·L-1, at the same time was 0.52 and 0.95 times of CARB refueling UEF (1008 mg·L-1) in A/L=0.The average value of emission factors respectively was (55±30) mg·L-1 and (112±108) mg·L-1 in A/L 1.05-1.07 in winter and summer. 3Refueling UEF without vapor recovery of social vehicles was chosen as the localized summer and winter refueling UEF in Beijing, we could calculate the emission factor of vapor recovery in different A/L combining with the linear equation of the fuel test tank.

16.
Chem Commun (Camb) ; 51(99): 17596-9, 2015 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-26482124

RESUMO

A general and efficient method for the synthesis of tertiary amides has been developed via the copper-catalyzed aerobic oxidative amidation of tertiary amines. Due to the use of the O2 oxidant, various functional groups were well tolerated under the present conditions. Extensive substrates studies demonstrated its potential as a practical approach for the synthesis of tertiary amides.

17.
Br J Pharmacol ; 172(23): 5634-46, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25953733

RESUMO

BACKGROUND AND PURPOSE: The epithelial sodium channel (ENaC) is expressed in vascular endothelial cells and is a negative modulator of vasodilation. However, the role of endothelial ENaCs in salt-sensitive hypertension remains unclear. Here, we have investigated how endothelial ENaCs in Sprague-Dawley (SD) rats respond to high-salt (HS) challenge. EXPERIMENTAL APPROACH: BP and plasma aldosterone levels were measured. We used patch-clamp technique to record ENaC activity in split-open mesenteric arteries (MAs). Western blot and Griess assay were used to detect expression of α-ENaCs, eNOS and NO. Vasorelaxation in second-order MAs was measured with wire myograph assays. KEY RESULTS: Functional ENaCs were observed in endothelial cells and their activity was significantly decreased after 1 week of HS diet. After 3 weeks of HS diet, ENaC expression was also reduced. When either ENaC activity or expression was reduced, endothelium-dependent relaxation (EDR) of MAs, in response to ACh, was enhanced. This enhancement of EDR was mimicked by amiloride, a blocker of ENaCs. By contrast, HS diet significantly increased contractility of MAs, accompanied by decreased eNOS activity and NO levels. However, ACh-induced release of NO was much higher in MAs isolated from HS rats than those from NS rats. CONCLUSIONS AND IMPLICATIONS: HS intake increased the BP of SD rats, but simultaneously enhanced EDR by reducing ENaC activity and expression due to feedback inhibition. Therefore, ENaCs may play an important role in endothelial cells allowing the vasculature to adapt to HS conditions.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Canais Epiteliais de Sódio/metabolismo , Cloreto de Sódio na Dieta/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/induzido quimicamente , Hipertensão/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Cloreto de Sódio na Dieta/administração & dosagem
18.
Br J Pharmacol ; 172(23): 5586-95, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25323043

RESUMO

BACKGROUND AND PURPOSE: Oestrogen inhibits cardiac hypertrophy and bone morphogenetic protein-4 (BMP4) induces cardiac hypertrophy. Here we have studied the inhibition by oestrogen of BMP4 expression in cardiomyocytes. EXPERIMENTAL APPROACH: Cultures of neonatal rat cardiomyocytes were used in in vitro experiments. Bilatαl ovariectomy (OVX) was carried out in female Kunming mice and cardiac hypertrophy was induced by transverse aortic constriction (TAC). KEY RESULTS: Oestrogen inhibited BMP4-induced cardiomyocyte hypertrophy and BMP4 expression in vitro. The inhibition of BMP4-induced BMP4 protein expression by oestrogen was prevented by the inhibitor of oestrogen receptor-ß, PHTPP, but not by the inhibitor of oestrogen receptor-α MPP. BMP4 induced smad1/5/8 activation, which was not affected by oestrogen in cardiomyocytes. BMP4 induced JNK but not ERK1/2 and p38 activation, and activated JNK was inhibited by oestrogen. Treatment with the p38 inhibitor SB203580 or the JNK inhibitor SP600125 inhibited BMP4-induced BMP4 expression in cardiomyocytes, but the ERK1/2 inhibitor U0126 increased BMP4-induced BMP4 expression, indicating that JNK, ERK1/2 and p38 MAPKs were all involved, although only JNK activation contributed to the inhibition of BMP4-induced BMP4 expression by oestrogen. TAC induced significant heart hypertrophy in OVX mice in vivo and oestrogen replacement inhibited TAC-induced heart hypertrophy in OVX mice. In parallel with the data of heart hypertrophy, oestrogen replacement significantly reduced the increased BMP4 protein expression in TAC-treated OVX mice. CONCLUSIONS AND IMPLICATIONS: Oestrogen treatment inhibited BMP4-induced BMP4 expression in cardiomyocytes through stimulating oestrogen receptor-ß and inhibiting JNK activation. Our results provide a novel mechanism underlying oestrogen-mediated protection against cardiac hypertrophy.


Assuntos
Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/metabolismo , Cardiomegalia/prevenção & controle , Estrogênios/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Animais , Proteína Morfogenética Óssea 4/biossíntese , Cardiomegalia/metabolismo , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Receptor beta de Estrogênio/metabolismo , Estrogênios/administração & dosagem , Feminino , Injeções Subcutâneas , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos , Camundongos Endogâmicos , Miócitos Cardíacos/metabolismo , Ratos , Relação Estrutura-Atividade
19.
Pflugers Arch ; 466(11): 2049-57, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24510064

RESUMO

Cardiac T-type Ca(2+) channels are reexpressed in atrial and ventricular myocytes under various pathological conditions such as post-myocardial infarction, hypertrophy, and heart failure, but relatively little is known about the mechanisms. Our previous study found that bone morphogenetic protein-4 (BMP4) was reexpressed in pathological cardiac hypertrophy models and BMP4-mediated cardiomyocyte hypertrophy. We hypothesized that BMP4 could upregulate cardiac T-type Ca(2+) channels in HL-1 atrial myocytes. The T-type Ca(2+) currents were recorded by using the patch-clamp technique, and the expressions of Cav3.1 and Cav3.2 were measured by real-time PCR method in HL-1 cells. BMP4 and Cav3.1 mRNA expressions increased in the left atrium from the pressure overload-induced hypertrophy of mice hearts. BMP4 treatment for 48 h induced increase of Cav3.1 but not Cav3.2 mRNA expression in HL-1 cells, and the increase was inhibited by BMP4 inhibitor noggin. Acute treatment with BMP4 did not affect T-type Ca(2+) currents, but chronic treatment (48 h) significantly increased the amplitude of T-type Ca(2+) currents in HL-1 cells. Chronic treatment with BMP4 induced upregulation of NADPH oxidase-4 (NOX4), increase of reactive oxygen species (ROS) level, and activation of mitogen-activated protein kinase (MAPK)-activated protein kinases c-jun N-terminal kinases (JNK) and p38. BMP4-induced upregulation of Cav3.1 mRNA was inhibited by NADPH oxidase inhibitor apocynin, the radical scavenger tempol, JNK inhibitor SP600125, and p38 inhibitor SB203580. In conclusion, BMP4 induces upregulation of Cav3.1 Ca(2+) channels and T-type Ca(2+) currents in HL-1 atrial myocytes through ROS/MAPK pathways.


Assuntos
Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/metabolismo , Canais de Cálcio Tipo T/genética , Canais de Cálcio Tipo T/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Cardiomegalia/genética , Cardiomegalia/metabolismo , Linhagem Celular Tumoral , Átrios do Coração/metabolismo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Camundongos , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NADPH Oxidase 4 , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , RNA Mensageiro/genética , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
20.
IEEE Trans Pattern Anal Mach Intell ; 36(1): 99-112, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24231869

RESUMO

We propose a new objective function for clustering. This objective function consists of two components: the entropy rate of a random walk on a graph and a balancing term. The entropy rate favors formation of compact and homogeneous clusters, while the balancing function encourages clusters with similar sizes and penalizes larger clusters that aggressively group samples. We present a novel graph construction for the graph associated with the data and show that this construction induces a matroid--a combinatorial structure that generalizes the concept of linear independence in vector spaces. The clustering result is given by the graph topology that maximizes the objective function under the matroid constraint. By exploiting the submodular and monotonic properties of the objective function, we develop an efficient greedy algorithm. Furthermore, we prove an approximation bound of (1/2) for the optimality of the greedy solution. We validate the proposed algorithm on various benchmarks and show its competitive performances with respect to popular clustering algorithms. We further apply it for the task of superpixel segmentation. Experiments on the Berkeley segmentation data set reveal its superior performances over the state-of-the-art superpixel segmentation algorithms in all the standard evaluation metrics.

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