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1.
Neural Netw ; 169: 92-107, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37864999

RESUMO

This paper examines the issue of almost periodic quasi-projective synchronization of delayed fractional-order quaternion-valued neural networks. First, using a direct method rather than decomposing the fractional quaternion-valued system into four equivalent fractional real-valued systems, using Banach's fixed point theorem, according to the basic properties of fractional calculus and some inequality methods, we obtain that there is a unique almost periodic solution for this class of neural network with some sufficient conditions. Next, by constructing a suitable Lyapunov functional, using the characteristic of the Mittag-Leffler function and the scaling idea of the inequality, the adequate conditions for the quasi-projective synchronization of the established model are derived, and the upper bound of the systematic error is estimated. Finally, further use Matlab is used to carry out two numerical simulations to prove the results of theoretical analysis.


Assuntos
Redes Neurais de Computação
2.
Comput Intell Neurosci ; 2022: 1779582, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36210995

RESUMO

This paper investigates the bifurcation issue of fractional-order four-neuron recurrent neural network with multiple delays. First, the stability and Hopf bifurcation of the system are studied by analyzing the associated characteristic equations. It is shown that the dynamics of delayed fractional-order neural networks not only depend heavily on the communication delay but also significantly affects the applications with different delays. Second, we numerically demonstrate the effect of the order on the Hopf bifurcation. Two numerical examples illustrate the validity of the theoretical results at the end.


Assuntos
Algoritmos , Redes Neurais de Computação , Neurônios/fisiologia
3.
Front Cell Infect Microbiol ; 12: 1001607, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36699719

RESUMO

Objectives: To develop a rapid and low-cost method for 16S rDNA nanopore sequencing. Methods: This was a prospective study on a 16S rDNA nanopore sequencing method. We developed this nanopore barcoding 16S sequencing method by adding barcodes to the 16S primer to reduce the reagent cost and simplify the experimental procedure. Twenty-one common pulmonary bacteria (7 reference strains, 14 clinical isolates) and 94 samples of bronchoalveolar lavage fluid from children with severe pneumonia were tested. Results indicating low-abundance pathogenic bacteria were verified with the polymerase chain reaction (PCR). Further, the results were compared with those of culture or PCR. Results: The turnaround time was shortened to 6~8 hours and the reagent cost of DNA preparation was reduced by employing a single reaction adding barcodes to the 16S primer in advance. The accuracy rate for the 21 common pulmonary pathogens with an abundance ≥ 99% was 100%. Applying the culture or PCR results as the gold standard, 71 (75.5%) of the 94 patients were positive, including 25 positive cultures (26.6%) and 52 positive quantitative PCRs (55.3%). The median abundance in the positive culture and qPCR samples were 29.9% and 6.7%, respectively. With an abundance threshold increase of 1%, 5%, 10%, 15% and 20%, the test sensitivity decreased gradually to 98.6%, 84.9%, 72.6%, 67.1% and 64.4%, respectively, and the test specificity increased gradually to 33.3%, 71.4%, 81.0%, 90.5% and 100.0%, respectively. Conclusions: The nanopore barcoding 16S sequencing method can rapidly identify the pathogens causing bacterial pneumonia in children.


Assuntos
Sequenciamento por Nanoporos , Pneumonia Bacteriana , Humanos , Criança , DNA Ribossômico/genética , Estudos Prospectivos , DNA Bacteriano/genética , DNA Bacteriano/análise , Bactérias , Pneumonia Bacteriana/diagnóstico , RNA Ribossômico 16S/genética
4.
Ann Anat ; 220: 51-54, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30063971

RESUMO

Intestinal tract is an important digestive organ, which takes on the functions of nutrient absorption, bile and metabolic waste excretion. Impaired intestinal barrier function might lead to inflammatory and intestinal diseases. Structure and function of intestinal tract is closely related to differentiation and development of intestinal cells. Differentiation and development of intestinal cells are coordinated and regulated via signaling pathways such as adenosine monophosphate-activated protein kinase (AMPK), Wnt and mammalian target of rapamycin (mTOR) signaling pathways. AMPK signaling pathway plays an important role in energy balance of intestinal cells and provides a theoretical basis for the treatment of intestinal diseases. Herein, we systematically summarizes the respective morphological characteristics of intestinal development in mammals, molecular mechanisms of intestinal development, AMPK signaling pathway and AMPK signaling pathway involved in intestinal tissue cell development.


Assuntos
Proteínas Quinases Ativadas por AMP/fisiologia , Intestinos/crescimento & desenvolvimento , Mamíferos/fisiologia , Transdução de Sinais/fisiologia , Animais , Humanos , Intestinos/anatomia & histologia , Intestinos/fisiologia
5.
Neural Plast ; 2018: 7513748, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29780409

RESUMO

Spinal cord injury (SCI) causes a high rate of morbidity and disability. The clinical features of SCI are divided into acute, subacute, and chronic phases according to its pathophysiological events. The mammalian target of rapamycin (mTOR) signaling pathway plays an important role in cell death and inflammation in the acute phase and neuroregeneration in the subacute/chronic phases at different times. Resveratrol has the potential of regulating cell growth, proliferation, metabolism, and angiogenesis through the mTOR signaling pathway. Herein, we explicate the role of resveratrol in the repair of SCI through the inhibition of the mTOR signaling pathway. The inhibition of the mTOR pathway by resveratrol has the potential of serving as a neuronal restorative mechanism following SCI.


Assuntos
Resveratrol/farmacologia , Transdução de Sinais/efeitos dos fármacos , Traumatismos da Medula Espinal/metabolismo , Medula Espinal/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Medula Espinal/metabolismo
6.
J Inequal Appl ; 2018(1): 245, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30839647

RESUMO

This paper is concerned with a class of quaternion-valued cellular neural networks with discrete and distributed delays. By using the exponential dichotomy of linear systems and a fixed point theorem, sufficient conditions are derived for the existence and global exponential stability of pseudo almost periodic solutions of this class of neural networks. Finally, a numerical example is given to illustrate the feasibility of the obtained results.

7.
J Zhejiang Univ Sci B ; 14(7): 563-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23825141

RESUMO

Arabidopsis trichomes are large branched single cells that protrude from the epidermis. The first morphological indication of trichome development is an increase in nuclear content resulting from an initial cycle of endoreduplication. Our previous study has shown that the C2H2 zinc finger protein GLABROUS INFLORESCENCE STEMS (GIS) is required for trichome initiation in the inflorescence organ and for trichome branching in response to gibberellic acid signaling, although GIS gene does not play a direct role in regulating trichome cell division. Here, we describe a novel role of GIS, controlling trichome cell division indirectly by interacting genetically with a key endoreduplication regulator SIAMESE (SIM). Our molecular and genetic studies have shown that GIS might indireclty control cell division and trichome branching by acting downstream of SIM. A loss of function mutation of SIM signficantly reduced the expression of GIS. Futhermore, the overexpression of GIS rescued the trichome cluster cell phenotypes of sim mutant. The gain or loss of function of GIS had no significant effect on the expression of SIM. These results suggest that GIS may play an indirect role in regulating trichome cell division by genetically interacting with SIM.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Ciclo Celular/metabolismo , Fatores de Transcrição/metabolismo , Tricomas/crescimento & desenvolvimento , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Divisão Celular , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Genótipo , Giberelinas/metabolismo , Inflorescência/genética , Microscopia Eletrônica de Varredura , Mutação , Fenótipo , RNA de Plantas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Fatores de Transcrição/genética , Dedos de Zinco
8.
New Phytol ; 198(3): 699-708, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23506479

RESUMO

The Arabidopsis trichome is a model system for studying cell development, cell differentiation and the cell cycle in plants. Our previous studies have shown that the ZINC FINGER PROTEIN5 (ZFP5) controls shoot maturation and epidermal cell fate through GA signaling in Arabidopsis. We have identified a novel C2H2 zinc finger protein ZINC FINGER PROTEIN 6 (ZFP6) which plays a key role in regulating trichome development in Arabidopsis. Overexpression of ZFP6 results in ectopic trichomes on carpels and other inflorescence organs. Gain- and loss-of-function analyses have shown that the zfp6 mutant exhibits a reduced number of trichomes in sepals of flowers, cauline leaves, lateral branch and main inflorescence stems in comparison to wild-type plants. Molecular and genetic analyses suggest that ZFP6 functions upstream of GIS, GIS2, ZFP8, ZFP5 and key trichome initiation regulators GL1 and GL3.We reveal that ZFP6 and ZFP5 mediate the regulation of trichome initiation by integrating GA and cytokinin signaling in Arabidopsis. These findings provide new insights into the molecular mechanism of plant hormone control of epidermal trichome patterning through C2H2 transcriptional factors.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Citocininas/metabolismo , Proteínas de Ligação a DNA/metabolismo , Giberelinas/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Diferenciação Celular/genética , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica de Plantas , Inflorescência/genética , Mutação , Epiderme Vegetal/citologia , Epiderme Vegetal/genética , Plantas Geneticamente Modificadas , Transdução de Sinais/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Dedos de Zinco/genética
9.
Zhong Yao Cai ; 33(4): 575-7, 2010 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-20845787

RESUMO

OBJECTIVE: To observe the effect on energy metabolism of rats with cold property Chinese medicine Radix Scutellariae. METHODS: The body weight gain, temperature, hydroposia content were determined before administration and every five days after administration. The activities of Na4(+)-K(+)-ATPase, Ca(2+)-ATPase and SDH, LPL, HP, the contents of NEAF, T3, T4, TSH were measured after having been administrated with water extracts of Radix Scutullaxiae at the dose of 6.0, 3.0 g/kg for 43 days. RESULTS: The body weight gains were raised and the hydroposia contents have been decreased. The activities of SDH were increased significantly while Na(+)-K(+)-ATPase, Ca(2+)-ATPase of liver had little change. The content of NEAF, the activity of LPL, HP were decreased significantly, and the contents of T3, T4, TSH and the body weight, temperature had no significant change. CONCLUSION: Radix Scutellariae can inhibit the energy metabolism of rat. The mechanism may not be related to thyroxine pathway.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Metabolismo Energético/efeitos dos fármacos , Fígado/metabolismo , Scutellaria baicalensis/química , Animais , Peso Corporal/efeitos dos fármacos , ATPases Transportadoras de Cálcio/metabolismo , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/isolamento & purificação , Ácidos Graxos não Esterificados/sangue , Lipase Lipoproteica/sangue , Fígado/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , ATPase Trocadora de Sódio-Potássio/metabolismo , Succinato Desidrogenase/metabolismo , Tiroxina/sangue , Tri-Iodotironina/sangue
10.
Zhongguo Zhong Yao Za Zhi ; 34(24): 3255-8, 2009 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-20353013

RESUMO

OBJECTIVE: To investigate the common rule hepatic energy metabolism on rats by six cold property of traditional Chinese medicines (TCM). METHOD: The activities of Na+ - K+ - ATPase, Ca2+ - ATPase and SDH, the content of hepatic glycogen, and the mRNA expression of hepatic uncoupling protein 2 (UCP2) were measured after the rats and been administrated with water extracts of Radix Sophorae Flavescentis, Fructus Gardeniae, Cortex Phellodendri, Radix Scutellariae, Rhizoma Coptidis, Radix Gentianae respectively at 6.0, 7.0, 8.4, 6.0, 7.0, 4.0 g x kg(-1) doses for 30 days, twice a day. RESULT: The activities of Na+ - K+ - ATPase, Ca2+ - ATPase and SDH were depressed significantly by six cold property TCM. The decreased tendency of SDH was observed by six cold property of TCM, while statistical significance was obtained in Cortex Phellodendri, Radix Scutellariae, Rhizoma Coptidis, Radix Gentianae. The increased tendency of hepatic glycogen content was found by six cold property TCM, while statistical significance was not obtained in six groups. The decreased tendency of the mRNA expression of UCP2 was found by six cold property TCM, while statistical significance was obtained in Radix Sophorae Flavescentis, Cortex Phellodendri, and Radix Scutellariae groups. CONCLUSION: The six cold property TCM have the good effects on hepatic energy metabolism by decreasing the activity of mitochondria SDH to reduce the production of ATP by decreasing the activities of Na+ - K+ - ATPase, Ca2+ - ATPase to cut down the consumption of ATP, by decreasing the mRNA expression of hepatic UCP2 to decrease the heat production.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Metabolismo Energético/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , ATPases Transportadoras de Cálcio/metabolismo , Coptis chinensis , Gardenia/química , Gentianaceae/química , Canais Iônicos/genética , Masculino , Proteínas Mitocondriais/genética , Reação em Cadeia da Polimerase , Ratos , Ratos Sprague-Dawley , Scutellaria baicalensis/química , ATPase Trocadora de Sódio-Potássio/metabolismo , Succinato Desidrogenase/metabolismo , Proteína Desacopladora 2
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