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1.
IEEE Trans Cybern ; PP2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36170392

RESUMO

In this article, two novel adaptive fault-tolerant control schemes for a class of nonlinear strict-feedback cyber-physical systems (CPSs) with deception attacks are presented. Deception attacks, such as false data-injection attacks, which destroy sensor networks, make the outputs and states of the CPSs unavailable. It is very difficult and challenging for a designer to achieve the tracking control under the circumstance of cyberattacks. To realize the tracking control for the studied CPSs, we propose a new coordinate transformation technology without precedent, where it takes the attack gains into account and uses the compromised states to design the corresponding controllers. In the backstepping design process, Nussbaum functions are presented to alleviate the influence of the unknown attack gains. Furthermore, we consider the actuator faults problem, which includes the loss of effectiveness and the bias fault. By skillfully designing the adaptive laws, the effect of actuator faults is completely eliminated. It is theoretically proved that the first proposed tracking control scheme can guarantee all signals in the closed-loop system are bounded and the output can track the desired reference signal. In addition, the second adaptive control scheme is also developed for the CPSs under the actuator faults and a more general assumption on the deception attacks is proposed simultaneously. Finally, the feasibility of the new proposed methods is verified by MATLAB simulation analysis.

2.
Acta Chim Slov ; 68(1): 205-211, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34057513

RESUMO

In this paper, we explored the synthesis of benzimidazole by the reaction of DMF and o-phenylenediamine. In the process of catalyst screening, we found that 4-amino-3-hydroxybenzoic acid, benzoic acid, and benzene-1,3,5-tricarboxylic acid could catalyze the reaction. Moreover, the calcium 4-amino-3-hydroxybenzoate and CO2 could more effectively catalyze the reaction, the synergistic effect of CO2 and 4-amino-3-hydroxybenzoic acid calcium salt can increase the yield of benzimidazole from 28% to 94%.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32294967

RESUMO

Migrant workers are an important human resource for economic and social development. Considering the government's goal of serving and improving people's livelihoods, improving the happiness of migrant workers is necessary. This study investigates in-depth the impact of the conversion of household registration on migrant workers' happiness, which is represented by a multi-dimensional comprehensive index based on the propensity matching score model and data from the China Migrants Dynamic Survey (CMDS) in 2017. Moreover, this study explores the different effects of conversion among the groups divided by the characteristics of migrant workers. The results show that from an overall perspective, although the conversion of household registration could improve the happiness of migrant workers, the degree of this improvement is minor. Further, the characteristics of the different groups, including age, educational background, contracted land, collective dividends, and income significantly affect the improvement of happiness. The conversion of household registration has obviously improved the happiness of migrant workers with low educational backgrounds, low income, and contracted land. Based on these findings, the government should take more targeted actions to improve the positive effects of household registration among different migrant worker groups due to the different characteristics in the process of household registration system reform.


Assuntos
Migrantes , Adulto , China , Características da Família , Felicidade , Humanos , Renda , Pessoa de Meia-Idade
5.
Gene ; 742: 144603, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32198126

RESUMO

Adverse environmental conditions, such as salinity, cold, drought, heavy metals, and pathogens affect the yield and quality of Salvia miltiorrhiza, a well-known medicinal plant used for the treatment of cardiovascular and cerebrovascular diseases. Superoxide dismutase (SOD), a key enzyme of antioxidant system in plants, plays a vital role in protecting plants against various biotic and abiotic stresses via scavenging the reactive oxygen species produced by organisms. However, little is known about the SOD gene family in S. miltiorrhiza. In this study, eight SOD genes, including three Cu/Zn-SODs, two Fe-SODs and three Mn-SODs, were identified in the S. miltiorrhiza genome. Their gene structures, promoters, protein features, phylogenetic relationships, and expression profiles were comprehensively investigated. Gene structure analysis implied that most SmSODs have different introns/exons distrbution patterns. Many cis-elements related to different stress responses or plant hormones were found in the promoter of each SmSOD. Expression profile analysis indicated that SmSODs exhibited diverse responses to cold, salt, drought, heavy metal, and plant hormones. Additionally, 31 types of TFs regulating SmSODs were predicted and analyzed. These findings provided valuable information for further researches on the functions and applications of SmSODs in S. miltiorrhiza growth and adaptation to stress.


Assuntos
Regulação da Expressão Gênica de Plantas , Família Multigênica/genética , Proteínas de Plantas/genética , Salvia miltiorrhiza/genética , Superóxido Dismutase/genética , Aclimatação/genética , Secas , Éxons/genética , Perfilação da Expressão Gênica , Íntrons/genética , Filogenia , Melhoramento Vegetal , Proteínas de Plantas/metabolismo , Salinidade , Salvia miltiorrhiza/enzimologia , Estresse Fisiológico/genética , Superóxido Dismutase/metabolismo , Fatores de Transcrição/metabolismo
6.
Neuroscience ; 411: 150-163, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31153963

RESUMO

Silent angina is a critical phenomenon in the clinic and is more commonly associated with women patients suffering from myocardial ischemia. Its underlying cause remains mysterious in medicine. With our recent discovery of female-specific Ah-type baroreceptor neurons (BRNs), we hypothesize that cardiac analgesia is due to the direct activation of Ah-type BRNs by elevated levels of circulating serotonin (5-HT) myocardial infarction (MI) patients. Electromyography and the tail-flick reflex were assessed in control and MI-model rats to evaluate 5-HT-mediated BP regulation as well as peripheral and cardiac nociception. 5-HT or a 5-HT receptor agonist was microinjected into the nodose ganglion to confirm the involvement of the afferent pathway of the baroreflex arc. An inward current was observed in identified BRNs by applying a whole-cell patch-clamp technique in conjunction with qRT-PCR to verify the afferent-specific action of 5-HT and the expression of 5-HT receptors. Although the tail-flick reflex and mean arterial pressure were dramatically reduced in female MI rats with elevated serum 5-HT, intrapericardial capsaicin-evoked muscular discharges were significantly inhibited in comparing with those of males, which were mimicked by microinjection of 5-HT or SR57227A into the nodose. Ah-type BRNs displayed robust inward currents at lower concentrations of 5-HT than the C-type or the A-type, with significantly increased expression and cellular distribution of 5-HT3AR but not 5-HT3BR compared to the A- and C-types. Activation of 5-HT3AR in Ah-type BRNs by 5-HT contributes significantly to cardiac analgesia, which may suggest the pathogenic condition that silent angina occurs mainly in female patients.


Assuntos
Angina Pectoris/metabolismo , Pressão Sanguínea/fisiologia , Infarto do Miocárdio/metabolismo , Nociceptividade/fisiologia , Pressorreceptores/metabolismo , Serotonina/metabolismo , Animais , Barorreflexo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Gânglio Nodoso/efeitos dos fármacos , Gânglio Nodoso/metabolismo , Ratos , Receptores de Serotonina/metabolismo , Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia
7.
J Agric Food Chem ; 64(41): 7760-7769, 2016 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-27690419

RESUMO

Tanshinones are a group of active diterpenes with pharmacological properties that are widely used in the treatment of cardiovascular diseases. Jasmonate (JA) acts as an elicitor to enhance tanshinone biosynthesis in Salvia miltiorrhiza. However, because of high labor costs and undesirable chemical characteristics, the use of JA elicitation is still in the experimental stage. In our experiments, the overexpression of Lycopersicon esculentum (tomato) Prosystemin (LePS) in transgenic plants of S. miltiorrhiza increased their JA concentrations, significantly enhanced the production of tanshinone, and activated the expression of key genes in the tanshinone biosynthesis pathway. Meanwhile, the relative levels of metabolites related to defense such as sterols, terpenes, and phenolic acids were also increased in our OEP lines. In addition, when the larvae of cotton bollworms (Heliothis armigera) were fed with leaves from transgenic lines, their mortality rates rose by nearly 4-fold when compared to that of larvae exposed to leaves from the nontransformed wild type. Our study provides a new strategy for genetic engineering by which tanshinone production and pest resistance can be improved in S. miltiorrhiza. This is accomplished by simulating the wounding signal that increases the endogenous levels of JA.

8.
Hypertension ; 67(4): 783-91, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26883269

RESUMO

This study aims to understand the special expression patterns of angiotensin-II receptor (AT1R and AT2R) in nodose ganglia and nucleus of tractus solitary of baroreflex afferent pathway and their contribution in sex difference of neurocontrol of blood pressure regulation. In this regard, action potentials were recorded in baroreceptor neurons (BRNs) using whole-cell patch techniques; mRNA and protein expression of AT1R and AT2R in nodose ganglia and nucleus of tractus solitary were evaluated using real time-polymerase chain reaction, Western blot, and immunohistochemistry at both tissue and single-cell levels. The in vivo effects of 17ß-estradiol on blood pressure and AT2R expression were also tested. The data showed that AT2R, rather than AT1R, expression was higher in female than age-matched male rats. Moreover, AT2R was downregulated in ovariectomized rats, which was restored by the administration of 17ß-estradiol. Single-cell real time-polymerase chain reaction data indicated that AT2R was uniquely expressed in Ah-type BRNs. Functional study showed that long-term administration of 17ß-estradiol significantly alleviated the blood pressure increase in ovariectomized rats. Electrophysiological recordings showed that angiotensin-II treatment increased the neuroexcitability more in Ah- than C-type BRNs, whereas no such effect was observed in A-types. In addition, angiotensin-II treatment prolonged action potential duration, which was not further changed by iberiotoxin. The density of angiotensin-II-sensitive K(+) currents recorded in Ah-types was equivalent with iberiotoxin-sensitive component. In summary, the unique, sex- and afferent-specific expression of AT2R was identified in Ah-type BRNs, and AT2R-mediated KCa1.1 inhibition in Ah-type BRNs may exert great impacts on baroreflex afferent function and blood pressure regulation in females.


Assuntos
Angiotensina II/farmacologia , Barorreflexo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Pressorreceptores/efeitos dos fármacos , Receptor Tipo 2 de Angiotensina/metabolismo , Potenciais de Ação/efeitos dos fármacos , Vias Aferentes/metabolismo , Análise de Variância , Animais , Barorreflexo/fisiologia , Pressão Sanguínea/fisiologia , Modelos Animais de Doenças , Feminino , Masculino , Gânglio Nodoso/metabolismo , Ovariectomia/métodos , Pressorreceptores/fisiologia , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Caracteres Sexuais
12.
Int J Biol Sci ; 9(10): 1079-88, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24339729

RESUMO

Evidence has shown gender differences regarding the critical roles of histamine in the prevalence of asthma, anaphylaxis, and angina pectoris. Histamine depolarizes unmyelinated C-type neurons without any effects on myelinated A-type vagal ganglion neurons (VGNs) in male rats. However, little is known if VGNs from females react to histamine in a similar manner. Membrane depolarization and inward currents were tested in VGNs isolated from adult rats using a whole-cell patch technique. Results from males were consistent with the literature. Surprisingly, histamine-induced depolarization and inward currents were observed in both unmyelinated C-type and myelinated A- and Ah-type VGNs from female rats. In Ah-type neurons, responses to 1.0 µM histamine were stronger in intact females than in males and significantly reduced in ovariectomized (OVX) females. In C-type neurons, histamine-induced events were significantly smaller (pA/pF) in intact females compared with males and this histamine-induced activity was dramatically increased by OVX. Female A-types responded to histamine, which was further increased following ovariectomy. Histamine at 300 nM depolarized Ah-types in females, but not Ah-types in OVX females. In contrast, the sensitivity of A- and C-types to histamine was upregulated by OVX. These data demonstrate gender differences in VGN chemosensitivity to histamine for the first time. Myelinated Ah-types showed the highest sensitivity to histamine across female populations, which was changed by OVX. These novel findings improve the understanding of gender differences in the prevalence of asthma, anaphylaxis, and pain. Changes in sensitivity to histamine by OVX may explain alterations in the prevalence of certain pathophysiological conditions when women reach a postmenopausal age.


Assuntos
Gânglios/efeitos dos fármacos , Histamina/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fatores Sexuais , Nervo Vago/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Feminino , Gânglios/fisiologia , Masculino , Bainha de Mielina/metabolismo , Neurônios/fisiologia , Ovariectomia , Ratos , Ratos Sprague-Dawley , Nervo Vago/fisiologia
13.
CNS Neurosci Ther ; 19(12): 954-62, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24164691

RESUMO

BACKGROUND: Baroreflex gain increase up closely to adult level during initial postnatal weeks, and any interruption within this period will increase the risk of cardiovascular problems in later of life span. We hypothesize that this short period after birth might be critical for postnatal development of vagal ganglion neurons (VGNs). METHODS: To evaluate neuroexcitability evidenced by discharge profiles and coordinate changes, ion currents were collected from identified A- and C-type VGNs at different developmental stages using whole-cell patch clamping. RESULTS: C-type VGNs underwent significant age-dependent transition from single action potential (AP) to repetitive discharge. The coordinate changes between TTX-S and TTX-R Na(+) currents were also confirmed and well simulated by computer modeling. Although 4-AP or iberiotoxin age dependently increased firing frequency, AP duration was prolonged in an opposite fashion, which paralleled well with postnatal changes in 4-AP- and iberiotoxin-sensitive K(+) current activity, whereas less developmental changes were verified in A-types. CONCLUSION: These data demonstrate for the first time that the neuroexcitability of C-type VGNs increases significantly compared with A-types within initial postnatal weeks evidenced by AP discharge profiles and coordinate ion channel changes, which explain, at least in part, that initial postnatal weeks may be crucial for ontogenesis in visceral afferent reflex function.


Assuntos
Potenciais de Ação/fisiologia , Neurônios/fisiologia , Reflexo/fisiologia , Nervo Vago/fisiologia , Fibras Aferentes Viscerais/fisiologia , 4-Aminopiridina/farmacologia , Fatores Etários , Animais , Animais Recém-Nascidos , Fibras Nervosas Mielinizadas/fisiologia , Fibras Nervosas Amielínicas/fisiologia , Técnicas de Patch-Clamp , Peptídeos/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Ratos , Ratos Sprague-Dawley , Bloqueadores dos Canais de Sódio/farmacologia , Tetrodotoxina/farmacologia
14.
Int J Biol Sci ; 9(7): 716-27, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23904796

RESUMO

Nodose ganglia are composed of A-, Ah- and C-type neurons. Despite their important roles in regulating visceral afferent function, including cardiovascular, pulmonary, and gastrointestinal homeostasis, information about subtype-specific expression, molecular identity, and function of individual ion transporting proteins is scarce. Although experiments utilizing the sliced ganglion preparation have provided valuable insights into the electrophysiological properties of nodose ganglion neuron subtypes, detailed characterization of their electrical phenotypes will require measurements in isolated cells. One major unresolved problem, however, is the difficulty to unambiguously identify the subtype of isolated nodose ganglion neurons without current-clamp recording, because the magnitude of conduction velocity in the corresponding afferent fiber, a reliable marker to discriminate subtypes in situ, can no longer be determined. Here, we present data supporting the notion that application of an algorithm regarding to microscopic structural characteristics, such as neuron shape evaluated by the ratio between shortest and longest axis, neuron surface characteristics, like membrane roughness, and axon attachment, enables specific and sensitive subtype identification of acutely dissociated rat nodose ganglion neurons, by which the accuracy of identification is further validated by electrophysiological markers and overall positive predictive rates is 89.26% (90.04%, 76.47%, and 98.21% for A-, Ah, and C-type, respectively). This approach should aid in gaining insight into the molecular correlates underlying phenotypic heterogeneity of nodose ganglia. Additionally, several critical points that help for neuron identification and afferent conduction calibration are also discussed.


Assuntos
Neurônios/fisiologia , Gânglio Nodoso/citologia , Potenciais de Ação/fisiologia , Animais , Animais Recém-Nascidos , Feminino , Masculino , Fibras Nervosas Mielinizadas/ultraestrutura , Fibras Nervosas Amielínicas/ultraestrutura , Neurônios/citologia , Técnicas de Patch-Clamp , Ratos , Ratos Sprague-Dawley
15.
Beijing Da Xue Xue Bao Yi Xue Ban ; 45(3): 412-6, 2013 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-23774919

RESUMO

OBJECTIVE: To further investigate the effects of silver ion (Ag+) dissolved from silver nanoparticles (AgNps) on gap junctional intercellular communication (GJIC) between HaCaT cells. METHODS: In this study, 20 000×g of 1 g/L AgNps suspension were centrifuged at 4 °C for 2 h, then the supernatant was collected as Ag(+) stock solution and measured by inductively coupled plasma mass spectrometry (ICP-MS); GJIC was detected by the scrape loading/dye transfer assay; connexin 43 (Cx43) protein and mRNA level were estimated by Western-blot and RT-PCR, respectively. RESULTS: Different concentrations of Ag(+) (0.01, 0.1 and 1.0 mg/L) did not affect the GJIC significantly. No notable changes were observed in expression of Cx43 protein and mRNA. CONCLUSION: The characteristics of Ag(+) and the effects on gap junctional intercellular communication between HaCaT cells may be different from those of AgNps.


Assuntos
Junções Comunicantes/efeitos dos fármacos , Nanopartículas Metálicas/química , Prata/farmacologia , Pele/citologia , Western Blotting , Comunicação Celular/efeitos dos fármacos , Conexina 43/metabolismo , Humanos , RNA Mensageiro
16.
Artigo em Inglês | MEDLINE | ID: mdl-17452795

RESUMO

TaLEA1, a gene encoding a late-embryogenesis-abundant protein, was cloned from wheat and was transformed into Salvia Miltiorrhiza Bunge by Agrobacterium-mediated leaf-disk transformation method. Seven transgenic lines were obtained after kanamycin (50 mg/L) screening. Six positive lines were obtained by PCR amplification, and after four additional generations, one stable line was obtained by Southern hybridization. Transgenic plants had better growth states than control plants on mediums containing 1% NaCl and 8% PEG6000, which demonstrated that TaLEA1 played an important role in increasing the salt and drought tolerance of S. miltiorrhiza.


Assuntos
Secas , Proteínas de Plantas/fisiologia , Plantas Geneticamente Modificadas/efeitos dos fármacos , Salvia miltiorrhiza/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Adaptação Fisiológica/fisiologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Reação em Cadeia da Polimerase , Rhizobium/genética , Salvia miltiorrhiza/genética , Salvia miltiorrhiza/fisiologia , Transformação Genética
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