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1.
Front Artif Intell ; 7: 1394101, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38915906

RESUMO

While encrypting information with color images, most encryption schemes treat color images as three different grayscale planes and encrypt each plane individually. These algorithms produce more duplicated operations and are less efficient because they do not properly account for the link between the various planes of color images. In addressing the issue, we propose a scheme that thoroughly takes into account the relationship between pixels across different planes in color images. First, we introduce a new 1D chaotic system. The performance analysis shows the system has good chaotic randomness. Next, we employ a shortest-path cross-plane scrambling algorithm that utilizes an enhanced Dijkstra algorithm. This algorithm effectively shuffles pixels randomly within each channel of a color image. To accomplish cross-plane diffusion, our approach is then integrated into the adaptive diffusion algorithm. The security analysis and simulation results demonstrate that the approach can tackle the issue of picture loss in telemedicine by encrypting color images without any loss of quality. Furthermore, the images we utilize are suitable for both standard RGB and medical images. They incorporate more secure and highly sensitive keys, robustly withstanding various typical ciphertext analysis attacks. This ensures a reliable solution for encrypting original images.

2.
World J Urol ; 42(1): 360, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811391

RESUMO

PURPOSE: To estimate the incidences of left renal vein (LRV) entrapment by right renal artery (RRA), a phenomenon primarily reported as case reports. METHODS: The cross-sectional study consecutively screened renal vessel CT data of 38 (Renal) patients with nephropathy and 305 (Non-renal) patients with peripheral arterial diseases in a teaching hospital in northeast China between November 2018 and March 2023. The LRV compression by adjacent anatomical structures, including but not limited to RRA and multiple compression-related parameters, were investigated through multiplanar analysis of the CT data. RESULTS: The overall LRV entrapment rates by adjacent structures were 41.93% (12/31) and 24.00% (6/25), the rates of RRA-sourced LRV compression 22.58% (7/31) and 20.00% (5/25), and the rates of compression by superior mesenteric artery (SMA) 16.13% (5/31) and 4.00% (1/25) in the Renal and Non-renal groups, respectively, with no significance. The venous segments distal to the RRA-compressed site had a significantly larger transectional lumen area than those of the non-compressed veins in both groups (3.09 ± 1.29 vs. 1.82 ± 0.23, p < 0.001 and 4.30 ± 2.65 vs. 2.12 ± 0.55, p = 0.006; maximum-to-minimum area ratios in Renal and Non-renal groups, respectively). Nearly 80% of RRAs were found arising anteriorly rightwards instead of passing straight to the right. CONCLUSION: RRA-sourced LRV compression was not rare, and its incidence was higher than that of the compression by SMA in both patient cohorts. RRA could be a more common compression source than SMA concerning LRV entrapment. Further investigations involving different populations, including healthy individuals, are needed.


Assuntos
Artéria Renal , Veias Renais , Humanos , Estudos Transversais , Pessoa de Meia-Idade , Masculino , Feminino , Veias Renais/diagnóstico por imagem , Veias Renais/anormalidades , Idoso , Artéria Renal/diagnóstico por imagem , Adulto , Tomografia Computadorizada por Raios X , Síndrome do Quebra-Nozes/complicações , Síndrome do Quebra-Nozes/diagnóstico por imagem , Incidência
3.
Plants (Basel) ; 12(5)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36904047

RESUMO

Photosynthetic efficiency under both steady-state and fluctuating light can significantly affect plant growth under naturally fluctuating light conditions. However, the difference in photosynthetic performance between different rose genotypes is little known. This study compared the photosynthetic performance under steady-state and fluctuating light in two modern rose cultivars (Rose hybrida), "Orange Reeva" and "Gelato", and an old Chinese rose plant Rosa chinensis cultivar, "Slater's crimson China". The light and CO2 response curves indicated that they showed similar photosynthetic capacity under steady state. The light-saturated steady-state photosynthesis in these three rose genotypes was mainly limited by biochemistry (60%) rather than diffusional conductance. Under fluctuating light conditions (alternated between 100 and 1500 µmol photons m-2 m-1 every 5 min), stomatal conductance gradually decreased in these three rose genotypes, while mesophyll conductance (gm) was maintained stable in Orange Reeva and Gelato but decreased by 23% in R. chinensis, resulting in a stronger loss of CO2 assimilation under high-light phases in R. chinensis (25%) than in Orange Reeva and Gelato (13%). As a result, the variation in photosynthetic efficiency under fluctuating light among rose cultivars was tightly related to gm. These results highlight the importance of gm in dynamic photosynthesis and provide new traits for improving photosynthetic efficiency in rose cultivars.

4.
Comput Math Methods Med ; 2022: 9880038, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35872932

RESUMO

Deep blind watermarking algorithms based on an end-to-end encoder-decoder architecture have recently been extensively studied as an important technology for protecting copyright. However, none of the existing algorithms can fully utilize the channel features of the image to improve the robustness against JPEG compression while obtaining high visual quality. Therefore, we propose firstly a mixed-frequency channel attention method in the encoder, which utilizes different frequency components of the 2D-DCT domain as weight coefficients during channel squeezing and excitation. Its essence is to suppress the useless feature maps and enhance the feature maps suitable for watermarking embedding by introducing frequency analysis in the channel dimension. The experimental results indicate that the PSNR of our method reaches over 38 and the BER is less than 0.01% under the JPEG compression with quality factor Q = 50. Besides, the proposed framework also obtains excellent robustness for a variety of common distortions, including Gaussian filter, crop, crop out, and drop out.


Assuntos
Compressão de Dados , Interpretação de Imagem Assistida por Computador , Algoritmos , Atenção , Compressão de Dados/métodos , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Distribuição Normal
5.
Front Plant Sci ; 13: 1076037, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36618654

RESUMO

Introduction: Camellia is among the most ornamentally valuable flowers and plants worldwide. Flower abscission typically causes significant financial losses by the horticultural landscape. Previous research has revealed that phytohormones, transcription factors, and other genes involved in floral development regulate the maintenance and mortality of flowers. Methods: In this study, for the first time, the transcriptomes and targeted hormone metabolomics of three developmental stages of the receptacles of two distinct camellia strains (CF: abscission strain, CHF: nonabscission strain) were analyzed to determine their roles in regulating blossom abscission in camellia. Results: ABA content was shown to be considerably upregulated throughout all phases of CF development, as were the genes implicated in the ABA production pathway and their downstream counterparts. Highly expressed genes in CF were involved in galactose metabolism, phenylpropanoid biosynthesis, amino and nucleotide sugar metabolism, pentose and glucuronate interconversions, and MAPK. Among others, highly expressed genes in CHF are associated with fructose and mannose metabolism, alpha-linolenic acid metabolism, biosynthesis of secondary metabolites, starch and sucrose metabolism, and cutin, suberin, and wax biosynthesis. A vast variety of stress response-related pathways and redox-related activities were also shown to be active in CHF. In contrast, CF dramatically activated pathways associated with lignin production, keratinogenesis, cell wall biogenesis, and ABA response. A comparative transcriptomic study of the CF and CHF pathways revealed that the downstream response pathways of hormones, including CTK, BR, IAA, ethylene, and GA, were very active in CF, indicating a significant amount of signal transduction and transcriptional regulation by CF. In addition, members of the transcription factor family, such as MYB, bHLH, MADS, and WD40, may regulate flower abscission. Discussion: A comparative transcriptome analysis of two distinct strains of camellia receptacles elucidates the molecular processes and regulatory characteristics of flower abscission and provides direction for the targeted improvement and breeding of camellia.

6.
Oncol Lett ; 14(3): 3001-3005, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28928837

RESUMO

Bladder cancer is the most common malignant tumor of the urinary system, and it is also an important cause of death by cancer globally. Increasing number of studies have shown that miRNAs can be used as prognostic markers for cancers. This study made use of the data available in the Cancer Genome Atlas in order to statistically analyze reported expression levels of miRNAs in samples from bladder urothelial carcinoma patients. Clinical features from a total of 399 patients and the expression data for 1,581 kinds of miRNA were included in the study. Single factor Cox regression analysis was used to identify miRNAs related to survival times for the patients. Then, through multifactors Cox regression we sorted out the independent prognostic miRNAs for the carcinoma. According to our results, 19 miRNAs were closely related to the survival times of patients with bladder urothelial carcinoma, and 3 miRNAs including hsa-mir-518b (p=0.02), hsa-mir-192 (p=0.04) and hsa-mir-7705 (p=0.04) should be useful as independent prognostic factors in patients. In addition, the survival time of those expressing high levels of hsa-mir-7705 and hsa-mir-192 was less than the survival time of those with low expression levels. However, there were no obvious differences in the survival times between high and low expressors of hsa-mir-518b. According to our results, hsa-mir-7705, hsa-mir-192 and hsa-mir-518b can be applied as independent prognostic markers for bladder urothelial carcinoma.

7.
Plant Physiol Biochem ; 97: 255-63, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26492133

RESUMO

In plant evolution, because of its key role in sexual polyploidization or whole genome duplication events, diploid gamete formation is considered as an important component in diversification and speciation. Environmental stress often triggers unreduced gamete production. However, the molecular, cellular mechanisms and adverse temperature regulating diplogamete production in carnation remain poorly understood. Here, we investigate the cytological basis for 2n male gamete formation and describe the isolation and characterization of the first gene, DcPS1 (Dianthus Caryophyllus Parallel Spindle 1). In addition, we analyze influence of temperature stress on diploid gamete formation and transcript levels of DcPS1. Cytological evidence indicated that 2n male gamete formation is attributable to abnormal spindle orientation at male meiosis II. DcPS1 protein is conserved throughout the plant kingdom and carries domains suggestive of a regulatory function. DcPS1 expression analysis show DcPS1 gene probably have a role in 2n pollen formation. Unreduced pollen formation in various cultivation was sensitive to high or low temperature which was probably regulated by the level of DcPS1 transcripts. In a broader perspective, these findings can have potential applications in fundamental polyploidization research and plant breeding programs.


Assuntos
Dianthus/citologia , Dianthus/genética , Diploide , Células Germinativas Vegetais/citologia , Estresse Fisiológico/genética , Temperatura , Cromossomos de Plantas/genética , Clonagem Molecular , Flores/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Células Germinativas Vegetais/metabolismo , Especificidade de Órgãos/genética , Filogenia , Pólen/citologia , Pólen/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
8.
Eur J Drug Metab Pharmacokinet ; 40(3): 255-66, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24789580

RESUMO

Tectorigenin (Te) is a main active component in the flowers of Pueraria thomsonii Benth. and the rhizomes of Belamcanda chinensis (L.) DC. Previously, we have reported the pharmacokinetic properties of Te in rat plasma. The purpose of this study was to investigate the urinary excretion of Te after oral administration to rats at different dose levels. Using UHPLC/Q-TOFMS, totally 26 metabolites were detected in rat urine after oral administration of Te at dose of 65 and 130 mg/kg. Among them, nine metabolites, Te, tectorigenin-7-O-glucuronide-4'-sulfate (Te-7G-4'S), tectorigenin-7-O-glucuronide (Te-7G), tectorigenin-7-O-sulfate (Te-7S), tectorigenin-4'-O-glucuronide (Te-4'S), isotectorigenin, genistein, irisolidone-7-O-glucuronide (Ir-7G), and irisolidone, were identified by comparing the retention time, UV and MS spectra with those of authentic standards. A UHPLC/Q-TOFMS method for simultaneous quantification and semi-quantification of all the metabolites in urine was developed. The cumulative urinary excretions of Te and the major metabolite Te-7G were 1.99 and 5.80 µmol at 65 mg/kg, 3.05 and 6.48 µmol at 130 mg/kg, accounted for 4.17 % and 15.8, 2.81 and 9.49 % of administrated Te, respectively. The excretion rates of Te-7G, Te-7G-4'S, Ir-7G, and Te reached a maximum between 12 and 24 h after oral dosing at 65 and 130 mg/kg. The cumulative urine excretion rates of Te were 23.1 and 20.1 % within 72 h at 65 and 130 mg/kg, respectively. These results suggested that the glucuronidation was the primary metabolic pathway especially at low dose level.


Assuntos
Isoflavonas/administração & dosagem , Isoflavonas/urina , Administração Oral , Animais , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/metabolismo , Genisteína/metabolismo , Glucuronídeos/metabolismo , Isoflavonas/metabolismo , Masculino , Espectrometria de Massas/métodos , Pueraria/química , Ratos , Ratos Sprague-Dawley , Rizoma/química
9.
J Surg Res ; 178(1): 460-5, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22507688

RESUMO

BACKGROUND: Renal ischemia-reperfusion injury (IRI) is a complex pathophysiologic process involving cell apoptosis and oxidant damages that leads to acute renal failure in both native kidneys and renal allografts. Pioglitazone is a novel class of oral antidiabetic agents currently used to treat type 2 diabetes mellitus. Pioglitazone exerts protective effects on acute myocardial ischemia and acute cerebral ischemia. The aim of this study was to investigate the possible beneficial effects of pioglitazone on renal IRI in mice. METHODS: IRI was induced by bilateral renal ischemia for 45 min followed by reperfusion. Fifty-five healthy male Balb/c mice were randomly assigned to one of the following groups: PBS + IRI, pioglitazone + IRI, PBS + sham IRI, pioglitazone + sham IRI. Kidney function tests, histopathologic examination, renal cell Bcl-2, and Bax expression were determined 24 h after reperfusion. Animals' survival was examined 7 days after operation. RESULTS: Animals pretreated with pioglitazone had lower plasma levels of blood urea nitrogen and creatinine caused by IRI, lower histopathologic scores, and improved survival rates following IRI. Renal cell apoptosis induced by IRI was abrogated in kidneys of mice pretreated by pioglitazone, with an increase in Bcl-2 expression and a decrease in Bax expression. Furthermore, pioglitazone pretreatment protected against lethal renal IRI. CONCLUSIONS: Peroxisome proliferator-activated receptor activation by pioglitazone exerts protective effects on renal IRI in mice by abrogating renal cell apoptosis. Thus, pioglitazone could be a novel therapeutic tool in renal IRI.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Traumatismo por Reperfusão/tratamento farmacológico , Tiazolidinedionas/farmacologia , Injúria Renal Aguda/patologia , Animais , Apoptose/efeitos dos fármacos , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Modelos Animais de Doenças , Hipoglicemiantes/farmacologia , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pioglitazona , Distribuição Aleatória , Traumatismo por Reperfusão/patologia
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