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1.
Molecules ; 29(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38611778

RESUMO

Polymer research is currently focused on sustainable and degradable polymers which are cheap, easy to synthesize, and environmentally friendly. Silicon-based polymers are thermally stable and can be utilized in various applications, such as columns and coatings. Poly(silyl ether)s (PSEs) are an interesting class of silicon-based polymers that are easily hydrolyzed in either acidic or basic conditions due to the presence of the silyl ether Si-O-C bond. Synthetically, these polymers can be formed in several different ways, and the most effective and environmentally friendly synthesis is dehydrogenative cross coupling, where the byproduct is H2 gas. These polymers have a lot of promise in the polymeric materials field due to their sustainability, thermal stability, hydrolytic degradability, and ease of synthesis, with nontoxic byproducts. In this review, we will summarize the synthetic approaches for the PSEs in the recent literature, followed by the properties and applications of these materials. A conclusion and perspective will be provided at the end.

2.
Sci Rep ; 14(1): 8012, 2024 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580704

RESUMO

The objective of human pose estimation (HPE) derived from deep learning aims to accurately estimate and predict the human body posture in images or videos via the utilization of deep neural networks. However, the accuracy of real-time HPE tasks is still to be improved due to factors such as partial occlusion of body parts and limited receptive field of the model. To alleviate the accuracy loss caused by these issues, this paper proposes a real-time HPE model called CCAM - Person based on the YOLOv8 framework. Specifically, we have improved the backbone and neck of the YOLOv8x-pose real-time HPE model to alleviate the feature loss and receptive field constraints. Secondly, we introduce the context coordinate attention module (CCAM) to augment the model's focus on salient features, reduce background noise interference, alleviate key point regression failure caused by limb occlusion, and improve the accuracy of pose estimation. Our approach attains competitive results on multiple metrics of two open-source datasets, MS COCO 2017 and CrowdPose. Compared with the baseline model YOLOv8x-pose, CCAM-Person improves the average precision by 2.8% and 3.5% on the two datasets, respectively.


Assuntos
Benchmarking , Extremidades , Humanos , Redes Neurais de Computação , Postura , Gravação de Videoteipe
3.
Pest Manag Sci ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38451056

RESUMO

BACKGROUND: Nanguo pear is a distinctive pear variety in northeast China, grown mainly in mountainous areas. Due to terrain limitations, ground-based pesticide application equipment is difficult to use. This limitation could be overcome by using unmanned aerial vehicles (UAVs) for pesticide application in Nanguo pear orchards. This study evaluated the spraying performance of two UAVs in the Nanguo pear orchards and compared them with a manually used backpack electric sprayer (BES). The study also analyzed the effect of canopy size on droplet deposition and ground loss, and evaluated two sampling methods, leaf sampling and telescopic rod sampling. RESULTS: Compared to BESs, droplet deposition is lower for UAVs, but the actual pesticide active ingredient deposition is not necessarily lower given the solution concentration. The droplet deposition varies among different UAVs due to structural differences. Under the same UAV operating parameters, droplet deposition on trees with smaller canopy sizes is typically greater than that on trees with larger canopy sizes, and the ground loss was also more severe. Although telescopic rod sampling is a quick and convenient method, it can only reflect the trend of droplet deposition, and the data error is greater compared with leaf sampling. CONCLUSION: UAVs can achieve better droplet deposition in mountainous Nanguo pear orchards and does almost no harm to the operators compared with the BES. However, canopy size needs to be considered to adjust the application volume rate. Telescopic rods can be used for qualitative analyses, but are not recommended for quantitative analyses. © 2024 Society of Chemical Industry.

4.
Plant Physiol ; 194(3): 1577-1592, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38006319

RESUMO

The improvement of fruit quality, in particular sugar content, has been a major goal of plant breeding programmes for many years. Here, 2 varieties of the Ussurian pear (Pyrus ussuriensis), Nanguo, and its high-sucrose accumulation bud sport, Nanhong, were used to study the molecular mechanisms regulating sucrose transport in fruits. Comparative transcriptome analysis showed that in Nanhong fruit, an MYB transcription factor, PuMYB12, and a sucrose transporter protein, PuSUT4-like, were expressed at higher levels, while a paclobutrazol resistance transcription factor, PuPRE6, and a histone deacetylase (HDAC), PuHDAC9-like, were expressed at lower levels in Nanguo fruit. PuSUT4-like silencing and overexpression experiments in Nanguo pear showed that PuSUT4-like is essential for sucrose transportation. PuPRE6 and PuMYB12 act as antagonistic complexes to regulate PuSUT4-like transcription and sucrose accumulation. The histone deacetylation levels of the PuMYB12 and PuSUT4-like promoters were higher in Nanguo fruit than in Nanhong fruit, and Y1H assays showed that HDAC PuHDAC9-like bound directly to the promoters of PuMYB12 and PuSUT4-like. Our results uncovered transcription regulation and epigenetic mechanisms underlying sucrose accumulation in pears.


Assuntos
Pyrus , Fatores de Transcrição , Pyrus/genética , Melhoramento Vegetal , Histona Desacetilases/genética , Sacarose
5.
RSC Adv ; 13(38): 26392-26405, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37671347

RESUMO

One of the current challenges of working with nanomaterials in bioapplications is having a tool that is biocompatible (non-toxic) and produces stable, intense fluorescence for bioimaging. To address these challenges, we have developed a streamlined and one-pot synthetic route for silicon-based quantum dots (SiQDs) using a hydrothermal method. Part of our unique approach for designing the SiQDs was to incorporate (3-aminopropyl) triethoxysilane (APTES), which is an amphipathic molecule with hydroxyl and amine functional groups available for modification. In order to reduce the toxicity of APTES, we chose glucose as a reducing agent for the reaction. The resulting SiQDs produced potent, stable, potential dual-emissive fluorescence emission peaks in the visible and near-infrared (NIR) ranges. Both peaks could be used as distinguishing fluorescence signals for bioimaging, separately or in combination. The physical and optical properties of the SiQDs were determined under a range of environmental conditions. The morphology, surface composition, and electronic structure of the SiQDs were characterized using high resolution-transmission electronic microscopy (HR-TEM), energy dispersive X-ray spectroscopy (EDS), Fourier-transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The stability of the SiQDs was evaluated under a wide range of pHs. The biocompatibility and imaging potential of the SiQDs were tested in microvascular endothelial cells (MVEC), neural stem cells (NSC), and RAW 264.7 macrophage cells. The images obtained revealed different subcellular localizations, particularly during cell division, with distinct fluorescence intensities. The results demonstrated that SiQDs are a promising, non-toxic labeling tool for a variety of cell types, with the added advantage of having dual emission peaks both in visible and NIR ranges for bioimaging.

6.
IEEE Trans Neural Netw Learn Syst ; 34(9): 6081-6095, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34928806

RESUMO

Class imbalance is a common issue in the community of machine learning and data mining. The class-imbalance distribution can make most classical classification algorithms neglect the significance of the minority class and tend toward the majority class. In this article, we propose a label enhancement method to solve the class-imbalance problem in a graph manner, which estimates the numerical label and trains the inductive model simultaneously. It gives a new perspective on the class-imbalance learning based on the numerical label rather than the original logical label. We also present an iterative optimization algorithm and analyze the computation complexity and its convergence. To demonstrate the superiority of the proposed method, several single-label and multilabel datasets are applied in the experiments. The experimental results show that the proposed method achieves a promising performance and outperforms some state-of-the-art single-label and multilabel class-imbalance learning methods.

7.
Front Plant Sci ; 13: 976977, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36092405

RESUMO

Stone cells are sclerenchyma cells formed by deposition of lignin, which is the most significant factor limiting the quality of pears. Ca2+ was known to inhibit stone cells in pear fruits, but the underlying molecular mechanism remains unclear. Our study revealed that exogenous CaCl2 (Ca2+) treatment of "Nanguo" pear (Pyrus ussuriensis) suppressed the synthesis of lignin and stone cell production. We further analysed the transcriptomes using RNA-seq, identified a transcription factor, PuDof2.5, and its targets gene PuPRX42-like (lignin polymerase gene) expression decreased in CaCl2-treated samples, which are involved in suppressing lignin biosynthesis in pear fruit. PuDof2.5 was found to bind directly to the PuPRX42-like promoter and induced its transcription. Taken together, our results revealed that Ca2+ modulated the key lignin biosynthetic transcription factor PuDof2.5 to suppress stone cell production in pear fruits.

8.
J Gastroenterol Hepatol ; 37(3): 531-541, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34931384

RESUMO

BACKGROUND AND AIM: Anti-tumor necrosis factor-α (anti-TNF-α) agents have been used for inflammatory bowel disease; however, it has up to 30% nonresponse rate. Identifying molecular pathways and finding reliable diagnostic biomarkers for patient response to anti-TNF-α treatment are needed. METHODS: Publicly available transcriptomic data from inflammatory bowel disease patients receiving anti-TNF-α therapy were systemically collected and integrated. In silico flow cytometry approaches and Metascape were applied to evaluate immune cell populations and to perform gene enrichment analysis, respectively. Genes identified within enrichment pathways validated in neutrophils were tracked in an anti-TNF-α-treated animal model (with lipopolysaccharide-induced inflammation). The receiver operating characteristic curve was applied to all genes to identify the best prediction biomarkers. RESULTS: A total of 449 samples were retrieved from control, baseline, and after primary anti-TNF-α therapy or placebo. No statistically significant differences were observed between anti-TNF-α treatment responders and nonresponders at baseline in immune microenvironment scores. Neutrophil, endothelial cell, and B-cell populations were higher in baseline nonresponders, and chemotaxis pathways may contribute to the treatment resistance. Genes related to chemotaxis pathways were significantly upregulated in lipopolysaccharide-induced neutrophils, but no statistically significant changes were observed in neutrophils treated with anti-TNF-α. Interleukin 13 receptor subunit alpha 2 (IL13RA2) is the best predictor (receiver operating characteristic curve: 80.7%, 95% confidence interval: 73.8-87.5%), with a sensitivity of 68.13% and specificity of 84.93%, and significantly higher in nonresponders compared with responders (P < 0.0001). CONCLUSIONS: Hyperactive neutrophil chemotaxis influences responses to anti-TNF-α treatment, and IL13RA2 is a potential biomarker to predict anti-TNF-α treatment response.


Assuntos
Quimiotaxia , Doenças Inflamatórias Intestinais , Neutrófilos , Inibidores do Fator de Necrose Tumoral , Animais , Quimiotaxia/fisiologia , Resistência a Medicamentos , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Neutrófilos/fisiologia , Inibidores do Fator de Necrose Tumoral/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/efeitos dos fármacos
9.
Hortic Res ; 8(1): 249, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34848695

RESUMO

The production of reactive oxygen species (ROS) by NADPH oxidase, which is also referred to as respiratory burst oxidase homolog (RBOH), affects several processes in plants. However, the role of RBOHs in cell wall lignification is not well understood. In this study, we show that PuRBOHF, an RBOH isoform, plays an important role in secondary wall formation in pear stone cells. ROS were closely associated with lignin deposition and stone cell formation according to microscopy data. In addition, according to the results of an in situ hybridization analysis, the stage-specific expression of PuRBOHF was higher in stone cells than in cells of other flesh tissues. Inhibitors of RBOH activity suppressed ROS accumulation and stone cell lignification in pear fruit. Moreover, transient overexpression of PuRBOHF caused significant changes in the amount of ROS and lignin that accumulated in pear fruit and flesh calli. We further showed that PuMYB169 regulates PuRBOHF expression, while PuRBOHF-derived ROS induces the transcription of PuPOD2 and PuLAC2. The findings of this study indicate that PuRBOHF-mediated ROS production, which is regulated by a lignin-related transcriptional network, is essential for monolignol polymerization and stone cell formation in pear fruit.

10.
Artigo em Inglês | MEDLINE | ID: mdl-34138719

RESUMO

Cross-modality visible-infrared person reidentification (VI-ReID), which aims to retrieve pedestrian images captured by both visible and infrared cameras, is a challenging but essential task for smart surveillance systems. The huge barrier between visible and infrared images has led to the large cross-modality discrepancy and intraclass variations. Most existing VI-ReID methods tend to learn discriminative modality-sharable features based on either global or part-based representations, lacking effective optimization objectives. In this article, we propose a novel global-local multichannel (GLMC) network for VI-ReID, which can learn multigranularity representations based on both global and local features. The coarse- and fine-grained information can complement each other to form a more discriminative feature descriptor. Besides, we also propose a novel center loss function that aims to simultaneously improve the intraclass cross-modality similarity and enlarge the interclass discrepancy to explicitly handle the cross-modality discrepancy issue and avoid the model fluctuating problem. Experimental results on two public datasets have demonstrated the superiority of the proposed method compared with state-of-the-art approaches in terms of effectiveness.

11.
Clin Respir J ; 15(2): 163-168, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32975905

RESUMO

BACKGROUND: Erectile dysfunction (ED) with obstructive sleep apnoea (OSA) is a relatively common issue for men. A number of clinical studies have demonstrated that continuous positive airway pressure (CPAP) therapy may effectively alleviate ED symptoms from patients with OSA. METHODS: PubMed, MEDLINE, EMBASE and Cochrane Library databases were utilised and searched for the relevant studies up to September 2, 2019. The International Index of Erectile Function 5 (IIEF-5) scoring system from the patients before and after receiving their CPAP therapy were collected according to the strict inclusion and exclusion criteria. REVMEN 5.3 software was applied for the meta-analysis. RESULTS: A total of seven publications consisted of 206 ED patients with OSA were included in the study. ED patients with OSA received CPAP treatment were significantly improved based on the IIEF-5 scores [Weighted Mean Difference (WMD) = 1.14, 95% confidence interval (CI) = 0.89-1.38, z = 9.09, p < 0.0001].Our research found that the high heterogeneity is mainly due to Zhang's data, with a higher apnoea-hypopnea index (AHI) compared to the other included studies. A moderate heterogeneity (I2 = 54%, P = 0.05) was found after removal of Zhang's data. CONCLUSION: The results suggest that continuous positive airway pressure therapy relive erectile dysfunction symptoms in patients with obstructive sleep apnoea. However, further evidence is needed due to the insufficient number of included patients and high heterogeneity.


Assuntos
Disfunção Erétil , Apneia Obstrutiva do Sono , Pressão Positiva Contínua nas Vias Aéreas , Disfunção Erétil/terapia , Humanos , Masculino , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/terapia
12.
Artigo em Inglês | MEDLINE | ID: mdl-33294001

RESUMO

BACKGROUND: Metabolic syndrome (MS) is a complex multisystem disease. Traditional Chinese medicine (TCM) is effective in preventing and treating MS. Syndrome differentiation is the basis of TCM treatment, which is composed of location and/or nature syndrome elements. At present, there are still some problems for objective and comprehensive syndrome differentiation in MS. This study mainly proposes a solution to two problems. Firstly, TCM syndromes are concurrent, that is, multiple TCM syndromes may develop in the same patient. Secondly, there is a lack of holistic exploration of the relationship between microscopic indexes, and TCM syndromes. In regard to these two problems, multilabel learning (MLL) method in machine learning can be used to solve them, and a microcosmic syndrome differentiation model can also be built innovatively, which can provide a foundation for the establishment of the next model of multidimensional syndrome differentiation in MS. METHODS: The standardization scale of TCM four diagnostic information for MS was designed, which was used to obtain the results of TCM diagnosis. The model of microcosmic syndrome differentiation was constructed based on 39 physicochemical indexes by MLL techniques, called ML-kNN. Firstly, the multilabel learning method was compared with three commonly used single learning algorithms. Then, the results from ML-kNN were compared between physicochemical indexes and TCM information. Finally, the influence of the parameter k on the diagnostic model was investigated and the best k value was chosen for TCM diagnosis. RESULTS: A total of 698 cases were collected for the modeling of the microcosmic diagnosis of MS. The comprehensive performance of the ML-kNN model worked obviously better than the others, where the average precision of diagnosis was 71.4%. The results from ML-kNN based on physicochemical indexes were similar to the results based on TCM information. On the other hand, the k value had less influence on the prediction results from ML-kNN. CONCLUSIONS: In the present study, the microcosmic syndrome differentiation model of MS with MLL techniques was good at predicting syndrome elements and could be used to solve the diagnosis problems of multiple labels. Besides, it was suggested that there was a complex correlation between TCM syndrome elements and physicochemical indexes, which worth future investigation to promote the development of objective differentiation of MS.

13.
Molecules ; 25(18)2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32899682

RESUMO

Ring opening copolymerization (ROCOP) of epoxides and cyclic anhydrides has become an attractive approach for the synthesis of biodegradable polyesters with various compositions. Encouraged by the efficiency and versatility of a series of amido-oxazolinate zinc complexes, in this study they were shown to be active catalysts for the synthesis of unsaturated polyesters via ROCOP of maleic anhydride and various epoxides. The relative activity of epoxides in these reactions was observed to be styrene oxide > cyclohexene oxide > phenyl glycidyl ether, which could be correlated with the electronic and steric features of the substrate. To provide more structural possibilities for the polyesters, the difference in epoxide reactivity was exploited in an attempt to prepare block terpolymers from one anhydride and two epoxides. Terpolymerization was carried out in one or two steps in a single pot. The thermal characterization by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques suggested that the resulting materials were mostly random terpolymers.


Assuntos
Amidas/química , Compostos de Epóxi/química , Anidridos Maleicos/química , Oxazóis/química , Polimerização , Zinco/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cicloexenos/química , Espectroscopia de Prótons por Ressonância Magnética , Temperatura , Termogravimetria
14.
J Biomed Inform ; 106: 103435, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32360988

RESUMO

The task of electronic medical record named entity recognition (NER) refers to automatically identify all kinds of named entities in the medical record text. Chinese clinical NER remains a major challenge. One of the main reasons is that Chinese word segmentation will lead to the wrong downstream works. Besides, existing methods only use the information of the general field, not consider the knowledge from field of medicine. To address these issues, we propose a dynamic embedding method based on dynamic attention which combines features of both character and word in embedding layer. Domain knowledge is provided by word vector trained by domain dataset. In addition, spatial attention is added to enable the model to obtain more and more effective context encoding information. Finally, we conduct extensive experiments to demonstrate the effectiveness of our proposed algorithm. Experiments on CCKS2017 and Common dataset shows that the proposed method outperforms the baseline.


Assuntos
Registros Eletrônicos de Saúde , Envio de Mensagens de Texto , Algoritmos , Atenção , China
15.
J Sci Food Agric ; 100(13): 4766-4775, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32458515

RESUMO

BACKGROUND: Peel color is an economically relevant trait that influences the appearance and quality of red pear, whose red color is due to anthocyanin accumulation. Prohydrojasmon (PDJ), which has similar effects to endogenous jasmonates, was developed as a commercial bioregulator, particularly to improve fruits coloring. However, little information is available about the effect of PDJ on pears. This study investigated the effects of preharvest PDJ treatments on color development, phenolic compounds accumulation, and related gene expression in the red pear cultivar 'Nanhong'. The treatments were performed during the pre-color-change period by spraying 50 or 100 mg L-1 of PDJ on fruits. RESULTS: Preharvest PDJ treatments had a significant effect on color development, without affecting other quality parameters such as total soluble solids and fruit acidity. Liquid chromatography-mass spectrometry analysis showed that concentrations of anthocyanins and flavonols were enhanced in the peel after PDJ treatments, particularly when a concentration of 100 mg L-1 was used, whereas those of hydroxycinnamates and flavanols were decreased. After PDJ application, the transcription levels of anthocyanin biosynthesis genes PAL, CHS, CHI, ANS, F3H, and UFGT were enhanced, especially under the higher PDJ concentration tested. In addition, anthocyanin accumulation in the peels of PDJ-treated fruits was found to be positively correlated with the upregulation of the regulatory gene MYB114. CONCLUSION: Preharvest treatments with PDJ could be a useful tool to improve fruits coloring and increase phenolic content in pear. These findings also improve our understanding of the molecular mechanisms associated with PDJ-regulated anthocyanin accumulation in pear fruits.


Assuntos
Frutas/crescimento & desenvolvimento , Fenóis/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/genética , Pyrus/efeitos dos fármacos , Antocianinas/biossíntese , Cor , Frutas/química , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Fenóis/química , Proteínas de Plantas/metabolismo , Pyrus/genética , Pyrus/crescimento & desenvolvimento , Pyrus/metabolismo
16.
Protoplasma ; 257(1): 261-274, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31482203

RESUMO

As lignified stone cells reduce fruit quality, we investigated lignin deposition, phenolic metabolites, and expression of lignin biosynthetic genes during fruit development to elucidate the molecular mechanism of stone cell lignification using histological, biochemical, and transcriptional data from two Ussurian pear varieties (Jianba and Nanguo) with contrasting stone cell content. Lignin content and distribution coincided with stone cell accumulation. As per LC-MS analysis, Jianba exhibited higher levels of lignin monomers and hydroxycinnamates than Nanguo, consistently with lignin amount in each case. However, flavonoid content was much higher in Nanguo. Transcriptional data showed that most monolignol biosynthesis-related genes were particularly upregulated in Jianba during lignin accumulation; especially CCR and LAC, two monolignol biosynthesis-specific genes, were substantially upregulated in Jianba fruits at critical stages. Therefore, differences in stone cell content between "Jianba" and "Nanguo" may result from differential expression of lignin synthase genes located downstream of the lignin biosynthesis pathway. Taken together, our data may provide a deeper understanding of the molecular mechanism for stone cell lignification in pear fruit.


Assuntos
Frutas/genética , Regulação da Expressão Gênica de Plantas , Lignina/metabolismo , Pyrus/genética , Vias Biossintéticas/genética , Frutas/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Fenóis/metabolismo , Análise de Componente Principal , Propanóis/metabolismo , Pyrus/crescimento & desenvolvimento
17.
ChemSusChem ; 11(17): 2881-2888, 2018 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-29958332

RESUMO

Several degradable poly(silyl ether)s (PSEs) have been synthesized by dehydrogenative cross-coupling between bio-based 1,4:3,6-dianhydrohexitols (isosorbide and isomannide) and commercially available hydrosilanes. An air-stable manganese salen nitrido complex [MnV N(salen-3,5-tBu2 )] was employed as the catalyst. High-molecular-weight polymer was obtained from isosorbide and diphenylsilane (Mn up to 17000 g mol-1 ). Thermal analysis showed that these PSEs possessed high thermal stability with thermal decomposition temperatures (T-5 % ) of 347-446 °C and glass transition temperatures of 42-120 °C. Structure-property analysis suggested that steric bulk and molecular weight have a significant influence to determine the thermal properties of synthesized polymers. Importantly, these polymers were degraded effectively to small molecules under acidic and basic hydrolysis conditions.

18.
J. bras. pneumol ; 43(5): 373-379, Sept.-Oct. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-893860

RESUMO

ABSTRACT Objective: To evaluate systematically the effects of continuous positive airway pressure (CPAP) on blood pressure in patients with resistant hypertension and obstructive sleep apnea (OSA). Methods: The Cochrane Library, PubMed, ScienceDirect, and the Web of Science were searched for studies investigating the effects of CPAP on blood pressure in patients with resistant hypertension and OSA. The selected studies underwent quality assessment and meta-analysis, as well as being tested for heterogeneity. Results: Six randomized controlled trials were included in the meta-analysis. The pooled estimates of the changes in mean systolic blood pressure and mean diastolic blood pressure (as assessed by 24-h ambulatory blood pressure monitoring) were −5.40 mmHg (95% CI: −9.17 to −1.64; p = 0.001; I2 = 74%) and −3.86 mmHg (95% CI: −6.41 to −1.30; p = 0.00001; I2 = 79%), respectively. Conclusions: CPAP therapy can significantly reduce blood pressure in patients with resistant hypertension and OSA.


RESUMO Objetivo: Avaliar sistematicamente os efeitos da continuous positive airway pressure (CPAP, pressão positiva contínua nas vias aéreas) na pressão arterial em pacientes com hipertensão resistente e apneia obstrutiva do sono (AOS). Métodos: Estudos que investigassem os efeitos da CPAP na pressão arterial em pacientes com hipertensão resistente e AOS foram buscados nos seguintes bancos de dados eletrônicos: Cochrane Library; PubMed; ScienceDirect e Web of Science. Os estudos selecionados foram submetidos a avaliação de qualidade, meta-análise e teste de heterogeneidade. Resultados: Foram incluídos na meta-análise seis ensaios clínicos controlados aleatórios. As estimativas combinadas das alterações das médias de pressão arterial sistólica e pressão arterial diastólica (medidas por meio de monitoração ambulatorial da pressão arterial durante 24 h) foram de −5,40 mmHg (IC95%: −9,17 a −1,64; p = 0,001; I2 = 74%) e −3,86 mmHg (IC95%: −6,41 a −1,30; p = 0,00001; I2 = 79%), respectivamente. Conclusões: O tratamento com CPAP é capaz de reduzir significativamente a pressão arterial em pacientes com hipertensão resistente e AOS.


Assuntos
Humanos , Pressão Sanguínea/fisiologia , Pressão Positiva Contínua nas Vias Aéreas/métodos , Hipertensão/fisiopatologia , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/terapia , Monitorização Ambulatorial da Pressão Arterial , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
J Bras Pneumol ; 43(5): 373-379, 2017.
Artigo em Inglês, Português | MEDLINE | ID: mdl-28767770

RESUMO

OBJECTIVE: To evaluate systematically the effects of continuous positive airway pressure (CPAP) on blood pressure in patients with resistant hypertension and obstructive sleep apnea (OSA). METHODS: The Cochrane Library, PubMed, ScienceDirect, and the Web of Science were searched for studies investigating the effects of CPAP on blood pressure in patients with resistant hypertension and OSA. The selected studies underwent quality assessment and meta-analysis, as well as being tested for heterogeneity. RESULTS: Six randomized controlled trials were included in the meta-analysis. The pooled estimates of the changes in mean systolic blood pressure and mean diastolic blood pressure (as assessed by 24-h ambulatory blood pressure monitoring) were -5.40 mmHg (95% CI: -9.17 to -1.64; p = 0.001; I2 = 74%) and -3.86 mmHg (95% CI: -6.41 to -1.30; p = 0.00001; I2 = 79%), respectively. CONCLUSIONS: CPAP therapy can significantly reduce blood pressure in patients with resistant hypertension and OSA.


Assuntos
Pressão Sanguínea/fisiologia , Pressão Positiva Contínua nas Vias Aéreas/métodos , Hipertensão/fisiopatologia , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/terapia , Monitorização Ambulatorial da Pressão Arterial , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
ACS Omega ; 2(2): 582-591, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-31457456

RESUMO

Poly(silylether)s are interesting materials because of their degradation property under hydrolytic conditions and have been prepared via hydrosilylation polymerization from dicarbonyl and hydrosilanes, and via dehydrogenative cross-coupling of diols and hydrosilanes under catalytic conditions. Here, we present a manganese-salen compound based on an inexpensive and nontoxic metal that could effectively catalyze both polymerization reactions with hydrosilane. A series of poly(silylether)s containing various aliphatic and aromatic backbones have been synthesized from diol and dicarbonyl substrates. Moderate to high yields of polymers with number-average molecular weights up to 15 kg/mol are obtained. Because of the dual activity of the manganese catalyst, unsymmetrical substrates with mixed functional groups, such as p-hydroxybenzaldehyde, p-hydroxy benzylalcohol, and 3-(4-hydroxyphenyl)-1-propanol, have been employed to afford poly(silylether)s with multiple silicon connectivity in the main chain.

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