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1.
MAGMA ; 36(6): 933-943, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37566311

RESUMO

OBJECTIVE: To enhance RF safety when implantable medical devices are located within the body coil but outside the imaging region by using a secondary resonator (SR) to reduce electric fields, the corresponding specific absorption rate (SAR), and temperature change during MRI. MATERIALS AND METHODS: This study was conducted using numerical simulations with an American Society for Testing and Materials (ASTM) phantom and adult human models of Ella and Duke from Virtual Family Models, along with corresponding experimental results of temperature change obtained using the ASTM phantom. The circular SR was designed with an inner diameter of 150 mm and a width of 6 mm. Experimental measurements were carried out using a 3 T Medical Implant Test System (MITS) body coil, electromagnetic (EM) field mapping probes, and an ASTM phantom. RESULTS: The magnitudes of B1+ (|B1+|) and SAR1g were reduced by 15.2% and 5.85% within the volume of interest (VoI) of an ASTM phantom, when a SR that generates opposing electromagnetic fields was utilized. Likewise, the Δ|B1+| and ΔSAR1g were reduced by up to 56.7% and 57.5% within the VoI of an Ella model containing a copper rod when an opposing SR was used. CONCLUSION: A novel method employing the designed SR, which generates opposing magnetic fields to partially shield a sample, has been proposed to mitigate the risk of induced-RF heating at the VoI through numerical simulations and corresponding experiments under various conditions at 3.0 T.


Assuntos
Campos Eletromagnéticos , Próteses e Implantes , Humanos , Campos Magnéticos , Imagens de Fantasmas , Imageamento por Ressonância Magnética/métodos , Ondas de Rádio
2.
Public Health ; 202: 12-17, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34875531

RESUMO

OBJECTIVES: Accurate assessment of early non-alcoholic fatty liver disease (NAFLD) is important to reduce the possible complications. The purpose of the present study was to develop a simple algorithm for the screening of NAFLD in the Chinese population based on routine anthropometric data and laboratory tests. STUDY DESIGN: This is a cross-sectional design. METHODS: The subjects (1145) underwent routine physical examinations. The variables in the NAFLD index (NFI) were obtained by a stepwise multiple logistic regression analysis on 1000 bootstrap samples. The area under the receiver-operating characteristic (AUROC) was used to evaluate the accuracy of the NFI. RESULTS: Multivariate analysis showed that body mass index, fasting blood glucose, ratio of alanine aminotransferase to aspartate aminotransferase, and triglyceride were included in the final equation. The AUROC of the NFI was 0.919 (95% confidence interval = 0.901-0.937). An NFI of <31.0 excluded the possibility of NAFLD with a sensitivity of 96.9%, and at a value of >36.0, the NFI could detect NAFLD with a specificity of 98.9%. CONCLUSIONS: NFI was a cost-effective NAFLD-screening model, which had a high accuracy for predicting NAFLD at early stages in the Chinese population.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Alanina Transaminase , China , Estudos Transversais , Humanos , Triglicerídeos
3.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(3): 573-579, 2021 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-34145863

RESUMO

OBJECTIVE: To summarize and analyze the clinical characteristics of primary hyperpara-thyroidism (PHPT) with normocalcemic parathormone elevation (NPE) after surgical treatment, so as to improve the therapeutic ability and standardized post-operative follow-up of PHPT patients. METHODS: Nine patients who were diagnosed with PHPT in the Department of Endocrinology of China-Japan Friendship Hospital from August 2017 to November 2019 were selected as the subjects. They all developed NPE within 6 months after surgical treatment. The clinical features and outcomes were collected and analyzed retrospectively, in addition, the related literature was reviewed. RESULTS: Clinical features: among the 9 patients, 6 were middle-aged and elderly females and 3 were male. The main clinical manifestations were bone pain, kidney stones, nausea and fatigue except for one case of asymptomatic PHPT. Pre-operative examination showed high serum calcium [(3.33±0.48) mmol/L], low serum phosphorus [0.76 (0.74, 0.78) mmol/L], high 24-hour urinary calcium [8.1(7.8, 12.0) mmol/24 h], obviously elevated intact PTH [(546.1±257.7) ng/L], vitamin D deficiency [25-hydroxyvitamin D3 (21.0±5.7) nmol/L]. Serum levels of bone alkaline phosphatase [7 patients 41.3(38.6, 68.4) µg/L, 2 patients >90 µg/L] and N-terminal midcourse osteocalcin (>71.4 µg/L) were significantly elevated. The estimated glomerular filtration rate decreased in 2 patients. Imaging examination: 7 patients had osteoporosis. Renal calculi were found in 3 patients by renal ultrasound. Imaging examination of parathyroid glands found definite lesions in all the patients, including 2 cases of multiple lesions and 7 cases of single lesions. TREATMENT AND OUTCOME: two patients underwent parathyroidectomy, while other patients were treated with microwave thermal ablation. PTH increased 1 month after therapy [(255.0±101.4) ng/L], and no recurrent lesions were found by parathyroid ultrasound. After combined treatment with cal-cium and vitamin D for six months, PTH decreased significantly and the level of serum calcium remained normal at anytime during the follow-up period. CONCLUSION: The occurrence of postoperative NPE may be related to the higher pre-operative PTH, vitamin D deficiency and lower creatinine clearance. However, NPE may not predict recurrent hyperthyroidism or incomplete parathyroidectomy. Adequate calcium and vitamin D supplementation after surgery seems to be beneficial for patients with NPE. Post-operative follow-up of PHPT patients should be standardized to prevent and treat post-operative NPE.


Assuntos
Hiperparatireoidismo Primário , Hormônio Paratireóideo , Idoso , Cálcio , China , Feminino , Humanos , Hiperparatireoidismo Primário/cirurgia , Masculino , Pessoa de Meia-Idade , Paratireoidectomia , Estudos Retrospectivos
4.
MAGMA ; 33(5): 725-733, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31980963

RESUMO

OBJECTIVE: To improve sensitivity and uniformity of MR images obtained using a phased array RF coil, an inductively coupled secondary resonator with RF detuning circuits at 300 MHz was designed. MATERIALS AND METHODS: A secondary resonator having detuning circuits to turn off the resonator during the transmit mode was constructed. The secondary resonator was located at the opposite side of the four-channel phased array to improve sensitivity and uniformity of the acquired MR images. Numerical simulations along with phantom and in vivo experiments were conducted to evaluate the designed secondary resonator. RESULTS: The numerical simulation results of |B1+| in a transmit mode showed that magnetic field uniformity would be decreased with a secondary resonator having no detuning circuits because of unwanted interferences between the transmit birdcage coil and the secondary resonator. The standard deviation (SD) of |B1+| was decreased 57% with a secondary resonator containing detuning circuits. The sensitivity and uniformity of |B1-| in the receive mode using a four-channel phased array were improved with the secondary resonator. Phantom experiments using a uniform saline phantom had 20% improvement of the mean signal intensity and 50% decrease in the SD with the secondary resonator. Mice with excess adipose tissue were imaged to demonstrate the utility of the secondary resonator. CONCLUSION: The designed secondary resonator having detuning circuits improved sensitivity and uniformity of mouse MR images acquired using the four-channel phased array.


Assuntos
Imageamento por Ressonância Magnética , Ondas de Rádio , Animais , Desenho de Equipamento , Campos Magnéticos , Camundongos , Imagens de Fantasmas
5.
MAGMA ; 32(1): 15-23, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29948237

RESUMO

OBJECTIVE: Improve 19F magnetic resonance imaging uniformity of perfluorocarbon (PFC)-labeled cells by using a secondary inductive resonator tuned to 287 MHz to enhance the induced radio frequency (RF) magnetic field (B1) at 7.05 T. MATERIALS AND METHODS: Following Faraday's induction law, the sign of induced B1 made by the secondary resonator can be changed depending on the tuning of the resonator. A secondary resonator located on the opposite side of the phantom of the 19F surface coil can be shown to enhance or subtract the induced B1 field, depending upon its tuning. RESULTS: The numerical simulation results of rotating transmit B1 magnitude (|B 1 + |) and corresponding experimental 19F images were compared without and with the secondary resonator. With the secondary resonator tuned to 287 MHz, improvements of |B 1 + | and 19F image uniformity were demonstrated. The use of the secondary resonator improved our ability to visualize transplanted cell location non-invasively over a period of 6 weeks. CONCLUSION: The secondary resonator tuned to enhance the induced B1 results in improved image uniformity in a pre-clinical application, enabling cell tracking of PFC-labeled cells with the secondary resonator.


Assuntos
Rastreamento de Células/métodos , Imagem por Ressonância Magnética de Flúor-19 , Flúor/química , Campos Magnéticos , Transplante de Células-Tronco , Animais , Desenho de Equipamento , Fluorocarbonos , Camundongos , Modelos Teóricos , Imagens de Fantasmas , Ondas de Rádio , Razão Sinal-Ruído
6.
Artigo em Inglês | MEDLINE | ID: mdl-26931469

RESUMO

Family members (FMs) regularly attend cancer consultations with patients, may assume an array of roles (e.g. emotional, informational) and their involvement may result in benefits and/or challenges. Little is currently known about how oncology health professionals (HPs) view FMs who accompany a patient in consultations. This study aimed to explore the attitudes and practices of Australian oncologists and oncology nurses regarding family involvement in consultations. Eleven oncologists and 10 nurses from a range of subspecialties and tumour streams participated in semi-structured interviews. Interviews were transcribed and qualitatively analysed using framework analysis methods. Five relevant themes were identified: (1) the varied and dynamic nature of family roles during consultations; (2) positivity towards FMs; (3) the benefits of family involvement to the FM themselves; (4) current HP practices to facilitate positive family involvement; and (5) the challenges of family involvement in consultations and HP practices to manage them. Overall, participants held mostly positive attitudes towards family involvement. Although they identified a number of challenges which can arise when family are involved, many noted these situations are the exception, that there are strategies which can help to overcome the challenges, and that the benefits of family involvement typically outweigh the costs.


Assuntos
Atitude do Pessoal de Saúde , Família , Neoplasias/terapia , Oncologistas/psicologia , Enfermagem Oncológica , Prática Profissional , Adulto , Idoso , Austrália , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Relações Profissional-Família
7.
IEEE Trans Electromagn Compat ; 59(5): 1382-1389, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29456259

RESUMO

This study investigates the use of pads with high dielectric constant (HDC) materials to alter electromagnetic field distributions in patients during magnetic resonance imaging (MRI). The study was performed with numerical simulations and phantom measurements. An initial proof-of-concept and validation was performed using a phantom at 64 MHz, showing increases of up to 10% in electromagnetic field when using distilled water as the high dielectric material. Additionally, numerical simulations with computational models of human anatomy were performed at 128 MHz. Results of these simulations using barium titanate (BaTiO3) beads showed a 61% increase of [Formula: see text] with a quadrature driven RF coil and a 64% increase with a dual-transmit array. The presence of the HDC material also allowed for a decrease of SAR up to twofold (e.g., peak 10 g-averaged SAR from 54 to 22 W/kg with a quadrature driven RF coil and from 27 to 22 W/kg with a dual-transmit array using CaTiO3 powder at 128 MHz). The results of this study show that the use of HDC pads at 128 MHz for MRI spine applications could result in improved magnetic fields within the region of interest, while decreasing SAR outside the region.

8.
IEEE Trans Electromagn Compat ; 59(5): 1390-1399, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29456260

RESUMO

This study describes the MRI-related radio frequency (RF) safety evaluation of breast tissue expander devices to establish safety criteria. Numerical simulations and experimental measurements were performed at 64 MHz with a gel phantom containing a breast expander. Additionally, computational modeling was performed (64 and 128 MHz) with an adult female model, containing a virtually implanted breast tissue expander device for four imaging landmark positions. The presence of the breast tissue expander device led to significant alterations in specific absorption rate (SAR) and|B1+|distributions. The main source of SAR alterations with the use of the breast expander device was the saline-filled pouch of the expander. Conversely, the variation of RF magnetic field (B1+) was mainly caused by the metallic port. The measured values of electric field magnitude did not increase significantly due to the introduction of the expander device. The maximum 1g- or 10g-averaged SAR values in tissues near the implant were lower than those expected in other regions of the patient body with normalization of both|B1+|equal to 2 µT at the coil isocenter and whole body averaged SAR equal to 4W/kg.

9.
Bull Entomol Res ; 104(3): 323-33, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24555527

RESUMO

Control of the malaria vector An. gambiae is still largely obtained through chemical intervention using pyrethroids, such as permethrin. However, strains of An. gambiae that are resistant to the toxic effects of pyrethroids have become widespread in several endemic areas over the last decade. The objective of this study was to assess differences in five life-history traits (larval developmental time and the body weight, fecundity, hatch rate, and longevity of adult females) and energy metabolism between a strain of An. gambiae that is resistant to permethrin (RSP), due to knockdown resistance and enhanced metabolic detoxification, and a permethrin susceptible strain reared under laboratory conditions. We also quantified the expression levels of five antioxidant enzyme genes: GSTe3, CAT, GPXH1, SOD1, and SOD2. We found that the RSP strain had a longer developmental time than the susceptible strain. Additionally, RSP adult females had higher wet body weight and increased water and glycogen levels. Compared to permethrin susceptible females, RSP females displayed reduced metabolic rate and mitochondrial coupling efficiency and higher mitochondrial ROS production. Furthermore, despite higher levels of GSTe3 and CAT transcripts, RSP females had a shorter adult life span than susceptible females. Collectively, these results suggest that permethrin resistance alleles might affect energy metabolism, oxidative stress, and adult survival of An. gambiae. However, because the strains used in this study differ in their genetic backgrounds, the results need to be interpreted with caution and replicated in other strains to have significant implications for malaria transmission and vector control.


Assuntos
Anopheles/efeitos dos fármacos , Resistência a Inseticidas , Inseticidas/farmacologia , Permetrina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Anopheles/genética , Anopheles/crescimento & desenvolvimento , Anopheles/fisiologia , Peso Corporal/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Feminino , Larva/efeitos dos fármacos , Larva/genética , Larva/crescimento & desenvolvimento , Larva/fisiologia , Longevidade/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Reprodução/efeitos dos fármacos
10.
Bull Entomol Res ; 101(1): 53-62, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20961465

RESUMO

The flight distance, flight time and individual flight activities of males and females of Dendroctonus armandi were recorded during 96-h flight trials using a flight mill system. The body weight, glucose, glycogen and lipid content of four treatments (naturally emerged, starved, phloem-fed and water-fed) were compared among pre-flight, post-flight and unflown controls. There was no significant difference between males and females in total flight distance and flight time in a given 24-h period. The flight distance and flight time of females showed a significant linear decline as the tethered flying continued, but the sustained flight ability of females was better than that of males. The females had higher glycogen and lipid content than the males; however, there was no significant difference between both sexes in glucose content. Water-feeding and phloem-feeding had significant effects on longevity, survival days and flight potential of D. armandi, which resulted in longer feeding days, poorer flight potential and lower energy substrate content. Our results demonstrate that flight distances in general do not differ between water-fed and starved individuals, whereas phloem-fed females and males fly better than water-fed and starved individuals.


Assuntos
Besouros/fisiologia , Metabolismo Energético , Voo Animal , Animais , Composição Corporal , China , Comportamento Alimentar , Feminino , Glucose/metabolismo , Glicogênio/metabolismo , Metabolismo dos Lipídeos , Masculino , Dinâmica Populacional , Fatores Sexuais
11.
J Biosci ; 462021.
Artigo em Inglês | MEDLINE | ID: mdl-34313248

RESUMO

Autophagy affects the development, progression, and prognosis of various cancers including pancreatic cancer. To develop an autophagy-related prognostic model of pancreatic cancer, we systematically analyzed gene expression profile from The Cancer Genome Atlas and Genotype-Tissue Expression. Ten autophagy-relevant genes with potential prognostic values were identified, based on which a prognostic model was constructed. We divided patients into a high- and a low-risk group with this model. Time-dependent receiver operating characteristic and Kaplan-Meier curves were conducted to evaluate the accuracy of the model. The Area Under Curvevalues of this model at 12, 18, and 24 months were 0.76, 0.73, and 0.78, respectively. The model was further validated in two Gene Expression Omnibus datasets. Gene set enrichment analysis and Cibersort were applied to analyze immune infiltration patterns and immune checkpoint blockade (ICB) molecules. The expression of ICB molecules, such as PD-L1 and PD1, presented significant correlation with the risk score. In conclusion, the risk score model established herein has been proved to be robust for evaluating the prognosis of pancreatic cancer and facilitate to improve the efficacy of ICB.


Assuntos
Autofagia/genética , Neoplasias Pancreáticas/patologia , Perfilação da Expressão Gênica , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Estimativa de Kaplan-Meier , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/imunologia , Prognóstico
12.
Water Sci Technol ; 61(3): 729-35, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20150710

RESUMO

Pure water production and recovery of Ni(2+) from dilute NiSO(4) solution via improved electrodeionization (EDI) process were investigated. It was indicated that, with the feed water containing 50 mg L(-1) Ni(2+), the dilute resistivity of the EDI could achieve 3 MOmega cm which gave a Ni(2+) rejection more than 99.8% while the Ni(2+) was concentrated as high as 1,583 mg L(-1) in the concentrate stream. The current efficiency was as high as 40% and the concentrate factor could reach 31.7. The experiment results demonstrated that, just in a single process, it was feasible to purifying and concentrating dilute nickel wastewater synchronously by the EDI technology.


Assuntos
Galvanoplastia/métodos , Níquel/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Resinas de Troca Aniônica , Resinas de Troca de Cátion , Cátions Bivalentes/isolamento & purificação , Eletroquímica/métodos , Concentração de Íons de Hidrogênio , Íons , Cinética , Níquel/química , Permeabilidade , Soluções , Propriedades de Superfície , Eliminação de Resíduos Líquidos/instrumentação , Água , Purificação da Água/instrumentação , Purificação da Água/métodos
13.
Eur Rev Med Pharmacol Sci ; 24(11): 6360-6370, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32572933

RESUMO

OBJECTIVE: At present, the incidence of acute myocardial infarction is increasing year by year, and it has become one of the diseases with the highest mortality rate in humans. Myocardial ischemia-reperfusion injury (MIRI) is a major problem in the treatment of myocardial infarction, but clinically there is no effective way to treat MIRI. This study used Cystatin C (Cys C) to treat cardiomyocytes and rats to investigate the effect of Cys C on MIRI. MATERIALS AND METHODS: We used H2O2 to induce rat cardiomyocytes (H9c2 cells) injury and stimulated the cells with Cys C. Cell counting kit 8 (CCK8) assay was used to determine the optimal concentration of H2O2 and Cys C to stimulate H9c2 cells. We determined the effects of Cys C on oxidative stress and apoptosis levels in H9c2 cells by measuring the activity of dehydrogenase (LDH), superoxide dismutase (SOD) and malondialdehyde (MDA), and the expression of apoptosis-related molecules (caspase3/8/9, Bax and Bcl-2). Changes in the activity of the NF-κB signaling pathway in H9c2 cells were also detected. In addition, we made rat MIRI models by ligating the coronary arteries and used Cys C to treat rats to verify the effect of Cys C on MIRI. RESULTS: According to the results of the CCK8 assay, 1000 µM of H2O2 and 15 µM of Cys C were used to stimulate H9c2 cells. Cys C alleviated H2O2-induced H9c2 cell injury, manifested as a decrease in LDH and MDA activity and an increase in SOD activity. Cys C also reduced the apoptosis level in H9c2 cells. The activity of NF-κB signaling pathway in injured H9c2 cells was increased, and stimulation of Cys C could inhibit the NF-κB signaling pathway in H9c2 cells. The application of Cys C in MIRI rats also verified its therapeutic effect on MIRI. CONCLUSIONS: Cys C reduced the oxidative stress and apoptosis levels of cardiomyocytes by inhibiting the activity of NF-κB signaling pathway in cardiomyocytes, thereby reducing cardiomyocyte injury and treating MIRI.


Assuntos
Cistatina C/farmacologia , Peróxido de Hidrogênio/antagonistas & inibidores , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Cistatina C/administração & dosagem , Modelos Animais de Doenças , Peróxido de Hidrogênio/farmacologia , Injeções Subcutâneas , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
14.
Nanotechnology ; 20(42): 425601, 2009 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-19779231

RESUMO

We report for the first time the self-assembled growth of nanocomposites of 'TiO(2) nanopillars on Pb(Zr(0.52)Ti(0.48))O(3) (PZT) thin films' using a modified sol-gel processing. Both TiO(2) nanopillars and PZT thin films are simultaneously formed during the post-annealing process. The growth behaviours of TiO(2) nanopillars are controlled by adjusting the Ti excess amounts of PZT solutions and the post-annealing conditions. The self-assembled growth can be explained on the basis of the combined effects of five factors which can have influence during the annealing process: a Ti ion diffusion to the film surface, a phase separation of PZT and TiO(2), a void formation on the film surface, a Ti oxidation at the film surface under oxygen atmosphere, and a nanopillar growth on the film surface.

15.
Pol J Vet Sci ; 22(2): 423-426, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31269359

RESUMO

The pharmacokinetics of a diclofenac sodium was investigated in swine. A single intravenous (i.v.) or intramuscular (i.m.) injection of 5% diclofenac sodium (concentration = 2.5 mg · kg-1) was administered to 8 healthy pigs according to a two-period crossover design. The pharmacokinetic parameters were calculated by non-compartmental analysis with DAS2.1.1 software. After a single i.v. administration, the main pharmacokinetic parameters of diclofenac sodium injection in swine were as follows: the elimination half-time (T1/2ß) was 1.32±0.34 h; the area under the curve (AUC) was (55.50±5.50 µg · mL-1 h; the mean residence time (MRT) was 1.60±0.28 h; the apparent volume of distribution (Vd) was 0.50±0.05 L · kg-1; and the body clearance (CLB) was 0.26±0.04 L · (h · kg)-1. After the single i.m. administration, the pharmacokinetic parameters were as follows: peak time (Tmax) was 1.19±0.26 h; and peak concentration (Cmax) was 11.61±5.99 µg mL-1. The diclofenac sodium has the following pharmacokinetic characteristics in swine: rapid absorption and elimination; high peak concentration; and bioavailability.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Diclofenaco/farmacocinética , Suínos/sangue , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/sangue , Área Sob a Curva , Diclofenaco/administração & dosagem , Diclofenaco/sangue , Feminino , Meia-Vida , Injeções Intramusculares , Injeções Intravenosas , Masculino , Distribuição Aleatória
16.
Eur Rev Med Pharmacol Sci ; 22(20): 6922-6929, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30402858

RESUMO

OBJECTIVE: To explore the specific role of TUG1 in regulating the occurrence and progression of diabetic atherosclerosis and its underlying mechanism. PATIENTS AND METHODS: TUG1 expressions in coronary artery disease (CAD) tissues, normal arterial tissues, endothelial cells induced by high-dose glucose and tumor necrosis factor-α (TNF-α) were detected by quantitative Real-time polymerase chain reaction (qRT-PCR). The effects of TUG1 on proliferation, migration and cell cycle of human umbilical vein endothelial cells (HUVECs) were detected by cell counting kit-8 (CCK-8), transwell assay and flow cytometry, respectively. Subsequently, protein expressions of proliferation-related genes, cell cycle-related genes and Wnt pathway-related genes were detected by Western blot after altering TUG1 expression in HUVECs. Further rescue experiments were carried out to explore whether TUG1 could regulate diabetic atherosclerosis via Wnt pathway. RESULTS: Overexpressed TUG1 was found in CAD tissues and endothelial cells induced by high-dose glucose and TNF-α compared with those of controls. TUG1 overexpression remarkably promoted proliferation, migration and cell cycle of HUVECs. Protein expressions of ß-catenin and c-Myc were upregulated by overexpression of TUG1. Rescue experiments indicated that XAV-939, the inhibitor of Wnt pathway, could partially reverse the increased proliferative and migratory changes in HUVECs induced by TUG1 overexpression. CONCLUSIONS: We found that overexpressed TUG1 stimulates proliferation and migration of endothelial cells via Wnt pathway, thereby promoting the occurrence and progression of diabetic atherosclerosis.


Assuntos
Aterosclerose/genética , Diabetes Mellitus/fisiopatologia , RNA Longo não Codificante/genética , Ciclo Celular/genética , Movimento Celular/genética , Proliferação de Células/genética , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Regulação para Cima , Via de Sinalização Wnt/genética , beta Catenina/metabolismo
17.
Curr Biol ; 10(9): 535-8, 2000 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-10801443

RESUMO

Transforming growth factor beta (TGF-beta) is an important regulator of apoptosis in some cell types, but the underlying molecular mechanisms are largely unknown. TGF-beta signals through type I and type II receptors and downstream effector proteins, termed Smads. TGF-beta induces the phosphorylation of Smad2 and Smad3 (receptor-activated Smads) which associate with Smad4 and translocate to the nucleus, where they regulate gene transcription [1]. Smad7 protein is induced by TGF-beta1 and has been classified as an inhibitory Smad. Smad7 prevents phosphorylation of receptor-activated Smads, thereby inhibiting TGF-beta-induced signaling responses [1]. Smad7 expression is increased in rat prostatic epithelial cells undergoing apoptosis as a result of castration [2]. Here we have shown that TGF-beta1 treatment or ectopic expression of Smad7 in human prostatic carcinoma cells (PC-3U) induces apoptosis. Furthermore, TGF-beta1-induced apoptosis was prevented by inhibition of Smad7 expression, by antisense mRNA in stably transfected cell lines or upon transient transfection with antisense oligonucleotides in several investigated cell lines. These findings provide evidence for a new effector function for Smad7 in TGF-beta1 signaling.


Assuntos
Apoptose , Proteínas de Ligação a DNA/metabolismo , Transdução de Sinais , Transativadores/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Clorometilcetonas de Aminoácidos/farmacologia , Inibidores de Caspase , Inibidores de Cisteína Proteinase/farmacologia , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica , Humanos , Masculino , Neoplasias da Próstata , Proteína Smad7 , Transativadores/genética , Fator de Crescimento Transformador beta/farmacologia , Células Tumorais Cultivadas
19.
Bone ; 38(3): 378-86, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16256450

RESUMO

Clinically, osteopenia or low bone mass has been observed in a variety of chronic inflammatory diseases, and elevated proinflammatory mediators have implicated this process. The purpose of this study was to develop an in vivo model of bone loss induced by chronic systemic inflammation. Time-release pellets designed to deliver one of three doses of LPS: Low (3.3 microg/day), High (33.3 microg/day), or Placebo over 90 days, were implanted subcutaneously in 3-month-old male Sprague-Dawley rats (n = 8/group). Neutrophil counts, indicative of ongoing inflammation, were elevated (P < 0.05) in both LPS groups at 30 days post-implant and remained significantly elevated in the High dose throughout the 90-day study period. At the end of the study, bone loss occurred in the femur as indicated by decreased bone mineral density (BMD) in both LPS-treated groups, but vertebral BMD was reduced in the High dose animals only. Microcomputed tomography revealed that trabecular bone volume (BV/TV) of the proximal tibial metaphysis tended to be reduced in the High dose LPS group. Deleterious effects on trabecular number (TbN) and trabecular separation (TbSp) were observed in both LPS-treated groups, but only the High dose group reached statistical significance. These alterations in trabecular microarchitecture resulted in compromised biomechanical properties. No changes in cortical thickness, porosity, or area of the tibia midshaft were evident at either dose of LPS. Up-regulation of the proinflammatory mediators, cyclooxygenase (COX)-2, interleukin (IL)-1, and tumor necrosis factor (TNF)-alpha was demonstrated in the metaphyseal region where the deleterious effects of LPS were observed. In addition to these alterations in bone, trichrome staining indicated changes in the coronary arterioles, consistent with vascular disease. Utilization of a LPS time-release pellet appears to provide an in vivo model of chronic inflammation-induced bone loss and a potentially novel system to study concurrent development of osteopenia and vascular disease.


Assuntos
Doença das Coronárias/etiologia , Vasos Coronários/patologia , Modelos Animais de Doenças , Inflamação/patologia , Osteoporose/patologia , Ratos Sprague-Dawley , Absorciometria de Fóton , Animais , Fenômenos Biomecânicos , Densidade Óssea , Doença Crônica , Doença das Coronárias/patologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Fibrose/patologia , Imuno-Histoquímica , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/farmacologia , Masculino , Miocárdio/patologia , Osteoporose/complicações , Ratos , Tíbia/efeitos dos fármacos , Tíbia/metabolismo , Tomografia Computadorizada por Raios X
20.
Bone ; 39(6): 1331-42, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16890505

RESUMO

Previously, dietary supplementation with dried plums, a rich source of polyphenolic compounds with antioxidant and anti-inflammatory properties, has been shown to improve bone density, microstructure and biomechanics in female animal models of osteopenia. We designed this study to determine the extent to which dried plum prevents skeletal deterioration in gonadal hormone deficient male animals and to begin to understand its mechanism of action. Sixty 6-month-old male Sprague-Dawley rats were either sham-operated (Sham = 1 group) or orchidectomized (ORX = 4 groups) and randomly assigned to dietary treatments: standard semi-purified diet (Control) with either LD = 5%, MD = 15%, or HD = 25% (w/w) dried plum for 90 days. At the end of the treatment period, both the MD and HD dried plum completely prevented the ORX-induced decrease in whole body, femur, and lumbar vertebra bone mineral density (BMD). Biomechanical testing indicated that the MD and HD of dried plum prevented the ORX-induced decrease in ultimate load of the cortical bone as well as the compressive force and stiffness of trabecular bone within the vertebrae. Analyses of trabecular microarchitecture of the distal femur metaphysis and vertebral body revealed that HD dried plum protected against the decrease in trabecular bone volume (BV/TV) induced by ORX. In the distal femur, all doses of dried plum improved trabecular number (TbN) and separation (TbSp) compared to the ORX-control group, while MD and HD dried plum prevented the ORX-induced changes in vertebral TbN and TbSp. At the end of the 90-day treatment, no remarkable changes in serum osteocalcin or alkaline phosphatase in any of the treatment groups were observed, while serum insulin-like growth factor (IGF)-I was increased by dried plum. The ORX-induced increase in urinary deoxypyridinoline (DPD) excretion was completely prevented by all doses of dried plum coinciding with down-regulation of gene expression for receptor activator of NFkappa-B ligand (RANKL) and osteoprotegerin (OPG) in the bone. We conclude that dried plum prevents osteopenia in androgen deficient male rats, and these beneficial effects may be attributed in part to a decrease in osteoclastogenesis via down-regulation of RANKL and stimulation of bone formation mediated by IGF-I.


Assuntos
Suplementos Nutricionais , Fator de Crescimento Insulin-Like I/metabolismo , Osteoporose/metabolismo , Osteoporose/prevenção & controle , Prunus , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Animais , Antioxidantes/administração & dosagem , Sequência de Bases , Fenômenos Biomecânicos , Densidade Óssea , Osso e Ossos/metabolismo , Feminino , Flavonoides/administração & dosagem , Expressão Gênica , Masculino , Osteoporose/genética , Osteoprotegerina/genética , Fenóis/administração & dosagem , Polifenóis , Ligante RANK/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
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