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1.
J Acoust Soc Am ; 155(5): 2973-2989, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38717202

RESUMO

The detection probability of underwater weak targets using active sonar is low, and inter-pulse coherent integration can improve the signal-to-noise ratio of echoes. When a target executes a maneuvering turn, complex range and Doppler frequency migrations occur during the coherent integration time that decrease the coherent integration gain. Most existing integration methods simplify the target motion to a finite-order polynomial model but fail to integrate a maneuvering turning target (MTT) due to model mismatch. Hence, this study proposes an underwater MTT integration method based on the modified Radon-Fourier transform. The proposed method constructs a theoretically accurate motion model for the MTT and a phase compensation function to compensate for the Doppler frequency migration. Furthermore, it yields a well-focused integration peak in the range-velocity and offset angle-turn rate dimensions and accurately estimates the target motion parameters. Moreover, the proposed method is suitable for targets with radial and oblique uniform motions. The effectiveness of the proposed method is demonstrated through simulations and a lake test. The proposed method demonstrates good integration performance, with an integration gain approximately 4-7 dB higher than that of traditional methods when using 30 integration pulses.

2.
J Acoust Soc Am ; 154(5): 2843-2857, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37930179

RESUMO

Noncooperative maneuvering target motion analysis is one of the challenging tasks in the field of underwater target localization and tracking for passive sonar. Underwater noncooperative targets often perform various maneuvers, and the targets are commonly modeled as a combination of constant-velocity models and coordinate-turn models with unknown turning rates. Traditional algorithms for Doppler-bearing target motion analysis are incapable of processing noncooperative maneuvering targets because the algorithms rely on a priori information of the turning rate and the center frequency. To address these shortcomings, this paper proposes the joint estimated adaptive unscented Kalman filter (JE-AUKF) algorithm. The JE-AUKF places the center frequency and turning rate into the state vector and constructs a time-varying state model that self-adapts to a maneuvering target. The JE-AUKF also introduces a time-varying fading factor into the process noise covariance matrix to improve the tracking performance. Simulations and sea trials are conducted to compare the performance of the JE-AUKF with the iterative unscented Kalman filter, the interacting multiple model-unscented Kalman filter, the interacting multiple model-iterative unscented Kalman filter, and the interacting multiple model-joint estimated unscented Kalman filter. The result shows that the JE-AUKF achieves better tracking performance for noncooperative maneuvering targets.

3.
J Acoust Soc Am ; 153(2): 1027, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36859115

RESUMO

Conventional double differential phase-shift keying modulation amplifies the phase noise and performs poorly under the time-varying direct-sequence spread-spectrum (DSSS) communication system. Therefore, the authors propose an iterative reception for DSSS communication in time-varying underwater acoustic channels. First, bit-interleaved coded modulation with iterative decoding integrated with multi-symbol differential detection is used. Second, this paper uses cross correlation method to estimate and track the Doppler shift of each symbol. Based on Doppler estimates, a dynamic linear prediction model is proposed to estimate and track the channel phase variation. Third, an algorithm for adaptive selection of reference signals is utilized to recover the magnitude attenuation of correlation peaks. Numerical simulation results demonstrate that the proposed reception achieves around 9 dB gain compared to conventional differential decision reception under constant acceleration of 0.14 m/s2. During the acoustic communication experiment in Songhua Lake, the proposed reception was tested by using a moving source at a speed of 1-6 knots at 2-m depth and the farthest distance between the transceivers is 2.8 km. The proposed reception achieves only one frame error from a total of 205 frames collected in the lake experiment, and it also achieves error-free communications over 96 frames during a 10 km depth deep-sea experiment.

4.
Int Ophthalmol ; 43(2): 411-422, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35947253

RESUMO

PURPOSE: To investigate the pterygium prevalence and evaluate risk factors of pterygium in rural type 2 diabetic (D2M) patients aged 50 years and above in Funing Country, Jiangsu Province, China. METHODS: A cross-sectional ophthalmic survey was conducted in type 2 diabetes mellitus (D2M) patients aged ≥ 50 years in Funing County, Jiangsu Province, China, which was named Jiangsu Diabetic Eye Disease Study (JDEDS). All participants underwent a comprehensive questionnaire and ocular examination. Pterygium was diagnosed by slit lamp examination. The risk factors associated with pterygium were evaluated with logistic regression models. RESULTS: The prevalence of pterygium was 22.37% (n = 427) and 95% confidence interval (CI) (20.50-24.24%) in D2M patients aged 50 years and above in JDEDS. The prevalence of pterygium was 18.32% (95% CI 15.33-21.32%) in men and 24.43% (95% CI 22.06-26.80%) in women. Women had a higher prevalence than men (p = 0.001). Multivariate analysis showed, for male participants with D2M, pterygium was independently associated with increasing age [70-79 years: OR and 95% CI 2.49(1.20-5.18), p = 0.014; ≥ 80 years: 4.84(2.04-11.47), p < 0.001], while cigarette smoking was the protective factors, especially in current smoker [OR and 95% CI 0.79(0.67-0.92); p = 0.003]. For female participants with D2M, age [60-69 years OR and 95% CI 1.68(1.07-2.62), p = 0.023; 70-79 years: 2.62(1.69-4.06), p < 0.001; ≥ 80 years:3.24(1.70-5.90), p < 0.001], hypertension [OR and 95% CI 1.40(1.05-1.87), p = 0.024], BMI 24-27.9 [OR and 95% CI 1.20(1.00-1.44), p = 0.047], higher HbA1c [(5.6-7.9) % OR and 95% CI 1.42(1.10-1.82), p = 0.006; (8.0-9.9) %: 1.32(1.10-1.58), p = 0.003] were risk factors. CONCLUSIONS: D2M patients aged over 50 years has a high prevalence of pterygium in JDEDS. The pterygium prevalence is higher in female D2M participants. Diabetes and related factors may be risk factors of pterygium in female D2M patients. Further studies are needed to explore the gender difference in the pathogenesis of pterygium in D2M subjects.


Assuntos
Complicações do Diabetes , Diabetes Mellitus Tipo 2 , Pterígio , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , China/epidemiologia , Estudos Transversais , Complicações do Diabetes/complicações , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , População do Leste Asiático , Prevalência , Pterígio/diagnóstico , Pterígio/epidemiologia , Pterígio/etiologia , Fatores de Risco , População Rural , Idoso , Idoso de 80 Anos ou mais
5.
J Acoust Soc Am ; 151(5): 3426, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35649933

RESUMO

Direction-of-arrival (DOA) estimation is widely used in underwater detection and localization. To address the high-resolution DOA estimation problem, a DenseBlock-based U-net structure is proposed in this paper. U-net is a U-shaped fully convolutional neural network, which yields a two-dimensional image. DenseBlock is a more efficient structure than typical convolutional layers. The proposed network replaces the concatenated convolutional layers in the original U-net with DenseBlocks. Through training, the network can remove the interference of sidelobes and noise in a conventional beam forming bearing-time record (BTR) and get a clean BTR; hence, this method has narrow beam width and few sidelobes. In addition, the network can be trained by simulation data and applied in actual data when the simulated and actual data are similar in BTR features, so the method has high generalization. For a multi-target problem, the network does not need to be trained on all cases with different target quantities and therefore can reduce the training set size. As a data-driven method, it does not rely on prior assumptions of the array model and possesses better robustness to array imperfections than typical model-based DOA algorithms. Simulations and experiments verify the advantages of the proposed method.

6.
Mol Pharm ; 18(4): 1544-1557, 2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33621099

RESUMO

Complex iron nanoparticle-based drugs are one of the oldest and most frequently administered classes of nanomedicines. In the US, there are seven FDA-approved iron nanoparticle reference drug products, of which one also has an approved generic drug product (i.e., sodium ferric gluconate (SFG)). These products are indicated for the treatment of iron deficiency anemia and are administered intravenously. On the molecular level, iron nanomedicines are colloids composed of an iron oxide core with a carbohydrate coating. This formulation makes nanomedicines more complex than conventional small molecule drugs. As such, these products are often referred to as nonbiological complex drugs (e.g., by the nonbiological complex drugs (NBCD) working group) or complex drug products (e.g., by the FDA). Herein, we report a comprehensive study of the physiochemical properties of the iron nanoparticle product SFG. SFG is the single drug for which both an innovator (Ferrlecit) and generic product are available in the US, allowing for comparative studies to be performed. Measurements focused on the iron core of SFG included optical spectroscopy, inductively coupled plasma mass spectrometry (ICP-MS), X-ray powder diffraction (XRPD), 57Fe Mössbauer spectroscopy, and X-ray absorbance spectroscopy (XAS). The analysis revealed similar ferric-iron-oxide structures. Measurements focused on the carbohydrate shell comprised of the gluconate ligands included forced acid degradation, dynamic light scattering (DLS), analytical ultracentrifugation (AUC), and gel permeation chromatography (GPC). Such analysis revealed differences in composition for the innovator versus the generic SFG. These studies have the potential to contribute to future quality assessment of iron complex products and will inform on a pharmacokinetic study of two therapeutically equivalent iron gluconate products.


Assuntos
Medicamentos Genéricos/química , Compostos Férricos/química , Nanopartículas/química , Anemia Ferropriva/tratamento farmacológico , Química Farmacêutica , Cromatografia em Gel , Medicamentos Genéricos/administração & dosagem , Medicamentos Genéricos/farmacocinética , Medicamentos Genéricos/normas , Difusão Dinâmica da Luz , Estudos de Equivalência como Asunto , Compostos Férricos/administração & dosagem , Compostos Férricos/farmacocinética , Compostos Férricos/normas , Humanos , Nanopartículas/administração & dosagem , Nanopartículas/normas , Controle de Qualidade , Ultracentrifugação
7.
Pharm Res ; 38(7): 1263-1278, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34128146

RESUMO

A method to reproducibly mill abuse deterrent oxycodone hydrochloride (HCl) extended release (ER) tablets was developed for a nasal insufflation pharmacokinetic (PK) study. Several comminution methods were explored before determining that a conical mill resulted in controlled milling of tablets to a size range equal to or below 1000 µm. However, milling resulted in significant loss of oxycodone from abuse deterrent oxycodone HCl ER tablets compared to minimal oxycodone loss from oxycodone HCl immediate release (IR) tablets. Characterization of milled tablet powder showed that loss of oxycodone was not attributed to analytical procedures or oxycodone phase change during high intensity milling processes. The content uniformity of oxycodone in the milled tablet powder varied when ER and IR tablets were milled to a particle size distribution equal to or below 500 µm but did not vary when particles were sized above 500 µm to equal to or below 1000 µm. In addition, the initial excipient weight to drug substance weight ratio impacted the amount of oxycodone lost from the respective formulation. However, dissolution demonstrated that when oxycodone HCl ER tablets are milled, differences in excipient weight to drug substance weight ratio and particle size distribution of milled tablets did not result in significantly different release of oxycodone.


Assuntos
Formulações de Dissuasão de Abuso , Analgésicos Opioides/química , Composição de Medicamentos/métodos , Dependência de Morfina/prevenção & controle , Oxicodona/química , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/farmacocinética , Química Farmacêutica , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Liberação Controlada de Fármacos , Insuflação , Oxicodona/administração & dosagem , Oxicodona/farmacocinética , Pós , Imagem Individual de Molécula , Comprimidos
8.
J Acoust Soc Am ; 150(2): 952, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34470307

RESUMO

Underwater platforms provide long-term detection of undersea targets. In this paper, we propose a method for the estimation of target motion parameters by submerged static acoustic detection equipment. The proposed method is based on the Radon transform of modeling the target moving in a uniform straight line. The heading angle, the time to the closest point of approach (CPA), and the ratio of velocity to the horizontal range of the target at the CPA to the sensor are obtained by applying the generalized Radon transform (GRT) to bearing-time records. The velocity of the target is determined by applying the GRT to the line-spectrum-time records. Furthermore, the motion trajectory of the target with respect to the detection equipment can be calculated from the above parameters. To validate the feasibility and performance of the proposed method, computer simulations and sea trials based on a fixed single vector measurement system were analyzed in this paper. The results suggest that the proposed method can accurately estimate the motion parameters and can calculate the trajectory of the moving vessel along a straight line at constant velocity.

9.
Vasa ; 50(2): 110-115, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32933402

RESUMO

Our meta-analysis focused on the relationship between homocysteine (Hcy) level and the incidence of aneurysms and looked at the relationship between smoking, hypertension and aneurysms. A systematic literature search of Pubmed, Web of Science, and Embase databases (up to March 31, 2020) resulted in the identification of 19 studies, including 2,629 aneurysm patients and 6,497 healthy participants. Combined analysis of the included studies showed that number of smoking, hypertension and hyperhomocysteinemia (HHcy) in aneurysm patients was higher than that in the control groups, and the total plasma Hcy level in aneurysm patients was also higher. These findings suggest that smoking, hypertension and HHcy may be risk factors for the development and progression of aneurysms. Although the heterogeneity of meta-analysis was significant, it was found that the heterogeneity might come from the difference between race and disease species through subgroup analysis. Large-scale randomized controlled studies of single species and single disease species are needed in the future to supplement the accuracy of the results.


Assuntos
Aneurisma , Hiper-Homocisteinemia , Hipertensão , Homocisteína , Humanos , Hiper-Homocisteinemia/diagnóstico , Hiper-Homocisteinemia/epidemiologia , Plasma
10.
AAPS PharmSciTech ; 21(2): 40, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31897805

RESUMO

There is a need to develop in vitro dissolution methods that discriminate for particle size of the manipulated abuse deterrent formulation (ADF) and that can be used for in vivo predictive models since dissolution methods developed for intact formulation might not be suitable for manipulated ones. A vertical diffusion cell (VDC) and United States Pharmacopeia (USP) Apparatus 1, 2, and 4 were evaluated for measuring the dissolution of intact and manipulated metoprolol succinate tablets with abuse deterrent-like properties. These tablets were physically manipulated to produce fine (106-500 µm) and coarse (500-1000 µm) powder samples. The VDC method was not able to discriminate the effect of particle size on drug release with varied stirring rate (200 to 800 rpm), molecular weight cut-off (MWCO, 3-5 kDa to 12-14 kDa) of the diffusion membrane, or composition and ionic strength (0.45% and 0.9%) of receiver medium. Standard and modified USP Apparatus 1 and 2 methods were assessed; however, large variations (RSD > 20%) were observed with USP Apparatus 1 for manipulated product dissolution and floating powder samples caused failure of auto-sampling when using standard USP Apparatus 2. For the USP Apparatus 4 dissolution method, packing configuration (1, 3, 8 layers and blend), ionic strength of dissolution medium (0.017, 0.077, and 0.154 M additional NaCl), and flow rate (4, 8, 16 mL/min) were studied to discriminate the effect of particle size on release. The USP Apparatus 4 dissolution method was optimized by using a packaging configuration of 8 layers with 8 mL/min flow rate which exhibited low variability and complete drug release and it could be used for in vivo predictive models. The dissolution method variables can be optimized for a specific product for desirable reproducibility and discriminatory power when using USP Apparatus 4.


Assuntos
Formulações de Dissuasão de Abuso , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Uso Indevido de Medicamentos sob Prescrição/prevenção & controle , Difusão , Metoprolol/administração & dosagem , Metoprolol/química , Modelos Teóricos , Peso Molecular , Tamanho da Partícula , Pós , Solubilidade , Comprimidos
11.
J Cell Physiol ; 234(9): 16032-16042, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30770562

RESUMO

BACKGROUND: Uveal melanoma (UM) is an intraocular malignant tumor characterized by rapid progression and recurrence. The current conventional treatments are unsatisfactory. Histone acetylation at H3 lysine 56 (H3K56ac) has been reported to be a tumor suppressor in breast cancer. However, whether H3K56ac prevents the occurrence and development of UM remains uninvestigated. The study aimed to explore the regulatory effect of H3K56ac on Ras-PI3K-AKT induced UM cells proliferation and migration. METHODS: The vectors of pEGFP-RasWT , pEGFP-K-Ras G12V/Y40C , and pEGFP-N1 were transfected into MP46 cells, and protein levels of phosphorylated AKT Ser473 and H3K56ac were examined using western blot analysis. The effect of H3K56ac on cell proliferation and migration were studied using 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide, colony formation, and Transwell assays. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and chromatin immunoprecipitation assays were performed to determine the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) downstream genes. Further, the regulatory effects of silent mating type information regulation 2 homolog-1 (SIRT1), general control nonderepressible 5 (GCN5), and mouse double minute 2 homolog (MDM2) on Ras-PI3K-AKT affected H3K56ac expression were also investigated. RESULTS: H3K56ac expression was specifically downregulated by Ras-PI3K-AKT activation pathway. H3K56ac inhibited the tumorigenic effect of Ras-PI3K-AKT on MP46 cells viability, colony formation, and migration, as well as participated in regulating the transcription of PI3K/AKT downstream genes. SIRT1 silence recovered H3K56ac expression, and reversed the tumorigenic effect of Ras-PI3K-AKT activation on MP46 cells. Downregulation of H3K56ac induced by Ras-PI3K-AKT activation was found to be associated with MDM2-mediated the degradation of GCN5. CONCLUSIONS: The results demonstrated that Ras-PI3K-AKT signaling promoted UM cells proliferation and migration via downregulation of H3K56ac expression, which might be related to MDM2-mediated the degradation of GCN5.

12.
J Cell Physiol ; 234(9): 16011-16020, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30770563

RESUMO

Ras-extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) signaling has been proposed as the crucial regulators in the development of various cancers. Histone acetylation at H3 lysine 14 (H3K14ac) is closely associated with gene expression and DNA damage. However, whether H3K14ac participates in mediating Ras-ERK1/2-induced cell proliferation and migration in uveal melanoma cells remains unknown. The purpose of this study is to investigate the effect of H3K14ac on Ras-ERK1/2 affected uveal melanoma cell phenotypes. MP65 cells were transfected with Ras WT and Ras G12V/T35S , the unloaded plasmid of pEGFP-N1 served as a negative control. Protein levels of phosphorylated ERK1/2 Thr202 and H3K14ac were assessed by western blot assay. Cell viability, number of colonies, migration, and the downstream genes of ERK1/2 were analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2-H-tetrazolium bromide, soft-agar colony formation, transwell, and chromatin immunoprecipitation assays. HA-tag vectors of CLR3 and TIP60 and the small interfering RNAs that specific for CLR3 and MDM2 were transfected into MP65 cells to uncover the effects of CLR3, TIP60, and MDM2 on Ras-ERK1/2 mediated H3K14ac expression and MP65 cell phenotypes. We found that, Ras-ERK1/2 decreased H3K14ac expression in MP65 cells, and H3K14ac significantly suppressed Ras-ERK1/2-induced cell viability, colony formation, and migration in MP65 cells. Moreover, the transcription of CYR61, IGFBP3, WNT16B, NT5E, GDF15, and CARD16 was regulated by H3K14ac. Additionally, CLR3 silence recovered H3K14ac expression and reversed the effect of Ras-ERK1/2 on MP65 cell proliferation, migration and the mRNAs of ERK1/2 downstream genes. Besides, Ras-ERK1/2 decreased H3K14ac expression by MDM2-mediated TIP60 degradation. In conclusion, Ras-ERK1/2 promoted uveal melanoma cells growth and migration by downregulating H3K14ac via MDM2-mediated TIP60 degradation.

13.
J Cell Physiol ; 234(11): 21049-21059, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31016760

RESUMO

The potential usage of curcumin in diverse human diseases has been widely studied, including arteriosclerosis (AS). This study focused on investigating the relationship between curcumin and AS-associated microRNA, which may provide a better understanding of curcumin in a different mechanism. Human microvascular endothelial HMEC-1 cells were treated by curcumin alone or oxidized low-density lipoprotein (ox-LDL) plus curcumin, after which the following parameters were analyzed: cell viability, migration, and the expression of AS-associated factors. The regulatory effects of curcumin on miR-126 and signaling pathways involved in AS were then studied. Further, an animal model of AS was stimulated by feeding rabbits with 1% cholesterol diet. The effects of curcumin on the animal model were explored. We found that curcumin treatment significantly reduced HMEC-1 cells viability, migration, and the protein levels of MMP-2, MMP-9, and vascular endothelial growth factor (VEGF) in the presence or absence of ox-LDL. Meanwhile, the expression of VEGFR1 and VEGFR2 was repressed by curcumin. miR-126 was upregulated by curcumin. The abovementioned effects of curcumin on HMEC-1 cells were all attenuated when miR-126 was silenced. And also, VEGF was a target gene of miR-126, and curcumin could inhibit the activation of PI3K/AKT JAK2/STAT5 signaling pathways via miR-126. The effects of curcumin and its regulation on miR-126 and VEGF were confirmed in the animal model of AS. To sum up, curcumin exerted potent anti-AS property possibly via upregulating miR-126 and thereby inhibiting PI3K/AKT and JAK2/STAT5 signaling pathways.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Aterosclerose/metabolismo , Curcumina/farmacologia , Células Endoteliais/metabolismo , MicroRNAs/metabolismo , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Humanos , Coelhos , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
J Cell Physiol ; 234(11): 19921-19932, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30982977

RESUMO

With the changing lifestyle, venous thrombosis (VT) is becoming increasingly prevalent and poses a burden on the health economy. Endothelial progenitor cells (EPCs) are recruited into resolving VT. We aimed to investigate the effect of plasminogen activator inhibitor 1 (PAI-1) silencing on the recanalization of VT in rat EPCs. EPCs and VT rat models were cultured and treated with negative control-siRNA vector and PAI-1-siRNA vector, respectively. 4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, wound-healing test, and Matrigel-induced tubular experiment were performed to detect the ability of cell proliferation, migration, and EPCs lumen formation. Immunohistochemistry was used to observe the recanalization of thrombus. The messenger RNA (mRNA) and protein expression of PAI-1 and vascular endothelial growth factor (VEGF) were determined by reverse transcription quantitative polymerase chain reaction and Western blot analysis. PAI-1-siRNA enhances the luminal formation ability of EPCs and significantly promotes EPCs homing. In response to PAI-1 gene silencing, tissues from inferior vena cava displayed reduced mRNA and protein expression of PAI-1, increased VEGF expression as well as promoted lumen-like structures. PAI-1 gene silencing can promote the recanalization of VT by enhancement of the luminal formation ability of rats' EPCs.


Assuntos
Células Progenitoras Endoteliais/metabolismo , Inativação Gênica , Inibidor 1 de Ativador de Plasminogênio/genética , RNA Interferente Pequeno/metabolismo , Trombose Venosa/metabolismo , Antígeno AC133/metabolismo , Animais , Antígenos CD34/metabolismo , Movimento Celular , Proliferação de Células , Células Cultivadas , Neovascularização Fisiológica , Inibidor 1 de Ativador de Plasminogênio/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Montagem de Vírus
15.
Mol Pharm ; 16(3): 1272-1281, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30676753

RESUMO

Nanomedicines are nanoparticle-based therapeutic or diagnostic agents designed for targeted delivery or enhanced stability. Nanotechnology has been successfully employed to develop various drug formulations with improved pharmacokinetic characteristics, and current research efforts are focused on the development of new innovator and generic nanomedicines. Nanomedicines, which are often denoted as complex or nonbiological complex drugs, have inherently different physicochemical and pharmacokinetic properties than conventional small molecule drugs. The tools necessary to fully evaluate nanomedicines in clinical settings are limited, which can hamper their development. One of the most successful families of nanomedicines are iron-carbohydrate nanoparticles, which are administered intravenously (IV) to treat iron-deficiency anemia. In the U.S., the FDA has approved six distinct iron-carbohydrate nanoparticles but only one generic version (sodium ferric gluconate for Ferrlecit). There is significant interest in approving additional generic iron-carbohydrate drugs; however, the lack of a direct method to monitor the fate of the iron nanoparticles in clinical samples has impeded this approval. Herein we report a novel liquid chromatography-inductively coupled plasma-mass spectrometry (LC-ICP-MS) method that allows for the direct quantification of the iron-carbohydrate drugs in clinical samples, while simultaneously measuring the speciation of the iron released from the nanoparticles in biological samples. To our knowledge, this is the first time that iron nanoparticles have been observed in clinical samples, opening the door for direct pharmacokinetic studies of this family of drugs. This method has potential applications not only for iron-nanoparticle drugs but also for any nanomedicine with an inorganic component.


Assuntos
Cromatografia Líquida/métodos , Compostos Férricos/sangue , Compostos Férricos/química , Ferro/química , Espectrometria de Massas/métodos , Nanopartículas/química , Administração Intravenosa , Confiabilidade dos Dados , Composição de Medicamentos , Medicamentos Genéricos , Compostos Férricos/administração & dosagem , Voluntários Saudáveis , Humanos , Nanomedicina/métodos , Nanotecnologia/métodos , Sensibilidade e Especificidade
16.
J Acoust Soc Am ; 145(6): EL483, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31255152

RESUMO

The received low frequency signals in the long range shallow water will suffer severe attenuation and modal dispersion effect, which will distort the signal and deteriorate the communication performance. In this letter, a modal dispersion compensation receiver is proposed, which exploits the de-dispersion transform to compensate intra-mode dispersion and the rake combination to combine the multi-mode components. With the proposed receiver, the waveform expansion of high order modes is compensated, and thus more modes can be distinguished from the noise and the rake combination gain is improved, which leads to high communication accuracy. Simulation results show that the proposed receiver can achieve about 3 dB gain for the 40 km range and signal with a center frequency 400 Hz.

17.
J Acoust Soc Am ; 146(5): 3159, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31795695

RESUMO

A vector sensor can provide measurements of ocean acoustic fields in terms of the acoustic pressure and three-dimensional particle velocity, providing potentially highly-informative data for applications such as geoacoustic inversion. This paper applies nonlinear Bayesian inversion to vector sensor data to estimate seabed geoacoustic properties and uncertainties in South China Sea. Linear-frequency-modulated source transmissions, recorded as acoustic pressure and vertical particle velocity, are processed to estimate the vertical phase gradient of acoustic pressure at multiple frequencies as the inversion data. An advantage of this type of data is that it can be modeled without knowledge of the source spectrum, allowing inversion with an unknown source and a single sensor. Geoacoustic inversion of phase-gradient data is carried out and compared to inversion of the vertical acoustic impedance, another type of vector-sensor data, independent of the source spectrum, which has been considered previously. Model selection for the optimal number of seabed sediment layers is carried out using Bayesian information criterion, and parameter estimates, uncertainties, and correlations are calculated using delayed-rejection adaptive Metropolis-Hastings sampling. Results indicate a three-layer seabed model (including the semi-infinite basement), with properties in agreement with independent measurements including a high-resolution seismic profile and surficial sediment type from a core.

18.
Cell Physiol Biochem ; 47(5): 1809-1818, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29953969

RESUMO

BACKGROUND/AIMS: In the treatment of serious and symptomatic coronary heart disease (CHD), coronary artery bypass grafting (CABG) is a frequently utilized intervention. In addition, the risk of CHD is strongly associated with the low activity of paraoxonase-1 (PON1), whose 3'-UTR harbors an rs3735590 polymorphism. The aim of this study was to investigate whether the rs3735590 polymorphism could be used as a prognosis marker in chronic obstructive pulmonary disease (COPD) patients undergoing CABG. In addition, the hypothesis, i.e., the rs3735590 polymorphism may be involved in the regulation of PON1 gene expression via modulating its interaction with miRNAs, was tested in this study. METHODS: 292 patients diagnosed with COPD and treated with CABG were recruited for this study. Genomic DNA was extracted from clinical samples, and real-time quantitative PCR and Western-blot were used to measure the expression of miR-616 and PON1 in liver cells of different genotypes. RESULTS: 292 COPD patients were divided into three groups according to their genotypes, i.e., rs3735590: CC (212), TC (75), and TT (5), respectively (TC and TT were merged in one group of T carriers for statistical analyses). Patients with the CC genotype were associated with a shorter event-free survival time as compared to patients with the T genotypes. In addition, PON1 was confirmed as a direct target gene of miR-616, while experiments with primary cells of different genotypes showed that miR-616 inhibited the expression of PON1 in CC cells. On the contrary, rs3735590 impaired such inhibitory effect of miR-616 in TT cells. CONCLUSION: The rs3735590 polymorphism of PON1 acts as a prognostic biomarker in COPD patients treated by CABG.


Assuntos
Regiões 3' não Traduzidas , Arildialquilfosfatase/genética , Ponte de Artéria Coronária , Polimorfismo Genético , Doença Pulmonar Obstrutiva Crônica , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/enzimologia , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/mortalidade , Doença Pulmonar Obstrutiva Crônica/cirurgia , Taxa de Sobrevida
19.
Cell Physiol Biochem ; 49(4): 1499-1511, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30205377

RESUMO

BACKGROUND/AIMS: Recent studies have suggested that several lncRNAs contribute to the angiogenic function of endothelial cells. Herein, we set out to reveal whether lncRNA UCA1 has functions in endothelial angiogenesis. METHODS: The expression levels of lncRNA UCA1, miR-195 and CCND1 in human microvascular endothelial HMEC-1 cells were altered by transfection. Subsequently, cell viability, migration, tube formation and apoptosis of HMEC-1 cells were respectively assessed. The cross-talk between lncRNA UCA1, miR-195, CCND1, and MEK/ERK and mTOR signaling pathways were investigated by performing qRT-PCR and Western blotting. RESULTS: Silence of lncRNA UCA1 repressed HMEC-1 cells viability, migration, tube formation, and induced apoptosis. Meanwhile, silence of lncRNA UCA1 significantly up-regulated miR-195 expression. These alterations induced by lncRNA UCA1 were further enhanced by miR-195 overexpression, while were attenuated by miR-195 suppression. Moreover, silence of lncRNA UCA1 deactivated MEK/ERK and mTOR signaling pathways via a miR-195-dependent regulation. And the deactivation of MEK/ERK and mTOR signaling pathways led to a down-regulation of CCND1. CONCLUSION: This study demonstrates that silence of lncRNA UCA1 largely represses microvascular endothelial cells growth and tube formation. Silence of lncRNA UCA1 exerts its function possibly via up-regulation of miR-195, which in turn inactivates MEK/ERK and mTOR signaling pathways, and ultimately represses CCND1 expression.


Assuntos
Proliferação de Células , MicroRNAs/metabolismo , Neovascularização Fisiológica , RNA Longo não Codificante/metabolismo , Antagomirs/metabolismo , Caspase 3/metabolismo , Ciclina D1/metabolismo , Células Endoteliais/citologia , Células Endoteliais/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação da Expressão Gênica , Humanos , MAP Quinase Quinase Quinases/metabolismo , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Microvasos/citologia , Óxido Nítrico Sintase Tipo III/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Interferência de RNA , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
20.
Cell Physiol Biochem ; 51(4): 1739-1750, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30504696

RESUMO

BACKGROUND/AIMS: Radix notoginseng is a well-known traditional Chinese herbal medicine, has extensively pharmacological activities in cardiovascular system. Notoginsenoside R1 (NGR1) is one main active ingredient of Radix notoginseng. The purpose of this study was to evaluate the functional effects of NGR1 on atherosclerosis (AS). METHODS: Human umbilical vascular endothelial cells (HUVECs) were subjected to oxidized low density lipoprotein (ox-LDL), before which cells were preconditioned with NGR1. Cell Counting Kit-8 (CCK-8) assay, flow cytometry, Transwell assay, quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were carried out to assess the impacts of ox-LDL and NGR1 on HUVECs. Besides, the expression of microRNA-132 (miR-132), and the regulatory role of miR-132 in Matrix Gla Protein (MGP) expression were measured by qRT-PCR and Western blot. RESULTS: NGR1 pre-conditioning prevented ox-LDL-induced apoptosis, migration and overproduction of Monocyte Chemoattractant Protein 1 (MCP-1) and Intercellular Adhesion Molecule 1 (ICAM-1). miR-132 was up-regulated in response to ox-LDL while was down-regulated by NGR1 pre-conditioning. The protective actions of NGR1 in ox-LDL-treated HUVECs were enhanced by miR-132 inhibitor, while were attenuated by miR-132 mimic. Besides, the up-regulated miR-132 could further decrease the expression of MGP, which acted as an anti-migratory and anti-adhesive factor. Furthermore, ox-LDL-induced the activation of c-Jun N-terminal Kinase (JNK) and Nuclear Factor Kappa B (NF-κB) pathways were partially attenuated by NGR1, and were fully eliminated by NGR1 treatment together with MGP overexpression. CONCLUSION: NGR1 prevents ox-LDL-induced apoptosis, migration and adhesion-related molecule release in HUVECs possibly via down-regulating miR-132, and subsequent up-regulating MGP.


Assuntos
Aterosclerose/prevenção & controle , Regulação para Baixo/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Ginsenosídeos/farmacologia , Lipoproteínas LDL/metabolismo , MicroRNAs/genética , Substâncias Protetoras/farmacologia , Apoptose/efeitos dos fármacos , Aterosclerose/genética , Aterosclerose/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos
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