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RESUMEN Introducción . El consumo excesivo de sal (cloruro de sodio, NaCl) en la dieta conduce al desarrollo de hipertensión arterial (HTA) y daño de órgano blanco. Se sabe que los canales ClC-K1 y ClC-5 son reguladores esenciales del anión cloruro (Cl-), pero la contribución de este anión a los efectos deletéreos de la sal es aún desconocida. Objetivo . El objetivo de este trabajo fue evaluar la participación del Cl- en la respuesta inflamatoria y oxidativa renal y en el desarrollo de HTA. Material y métodos . Ratas Wistar macho se dividieron en cuatro grupos (n=8/grupo) y se alimentaron con diferentes dietas durante 3 semanas. control (grupo C); NaCl 8 % (grupo NaCl); dieta alta en Na+. citrato de sodio (Na3C6H5O7) 11,8 % (grupo Na); dieta alta en Cl-. cloruro de calcio (CaCl2) 3,80 %, cloruro de potasio (KCl) 3,06 % y cloruro de magnesio (MgCl2) 1,30 % (grupo Cl). Se determinó la presión arterial sistólica (PAS), función renal, marcadores de estrés oxidativo y de inflamación en corteza renal, y la expresion renal de los canales de cloruro ClC-K1 y ClC-5. Resultados . Se observó un aumento de la PAS, actividad de glutatión peroxidasa (GPx) y expresión renal de factor nuclear kappa B (NFkB) y receptor de angiotensina II tipo 1 (AT1R) en los grupos NaCl y Cl- (p<0,05). La producción de sustancias reactivas del ácido tiobarbitúrico (TBARS) aumentó en los grupos experimentales con respecto a C. La expresión de la proteína de Parkinson 7 (PARK7) disminuyó en el grupo Cl en comparación con C (p< 0,05). Los grupos NaCl y Cl- mostraron una mayor expresión de ClC-K1, mientras que ClC-5 se redujo en el grupo NaCl en comparación con C (p<0,05). Conclusión . El Cl- sería corresponsable, junto con el Na+, de desencadenar daño oxidativo e inflamatorio renal y aumentar la presión arterial; por ello se deduce la importancia de reducir la ingesta de ambos iones como medida preventiva no farmacológica para la prevención y control de la HTA. El rol de los canales ClC-K1 y ClC-5 como mediadores de este proceso queda aún por confirmarse.
ABSTRACT Background . Excessive consumption of salt (sodium chloride, NaCl) in the diet leads to the development of hypertension (HTN) and target organ damage. It is known that the ClC-K1 and ClC-5 channels are essential regulators of the chloride (Cl-) anion, but the contribution of this anion to salt-harmful effects remains unknown. Objective . The aim of this study was to evaluate the participation of Cl- in the renal inflammatory and oxidative response and in the development of HTN. Methods . Male Wistar rats were divided into four groups (n=8/group) and fed with different diets for 3 weeks. control (C group); NaCl 8% (NaCl group); high Na+ diet. sodium citrate (Na3C6H5O7) 11.8% (Na group); high Cl- diet. calcium chloride (CaCl2) 3.80%, potassium chloride (KCl) 3.06% and magnesium chloride (MgCl2) 1.30% (Cl group). Systolic blood pressure (SBP), renal function, oxidative stress and inflammation markers in the renal cortex, and renal expression of the chloride ClC-K1 and ClC-5 channels were assessed. Results . An increase in SBP, glutathione peroxidase (GPx) activity, and renal expression of nuclear factor kappa B (NFkB) and angiotensin II type 1 receptor (AT1R) were observed in the NaCl and Cl groups (p<0.05). The production of thiobarbituric acid reactive substances (TBARS) increased in the experimental groups compared with C. The expression of Parkinson disease protein 7 (PARK7) decreased in the Cl group compared with C (p< 0.05). The NaCl and Cl groups showed increased expression of ClC-K1, while ClC-5 was reduced in the NaCl group compared with C (p<0.05) Conclusion . Cl- would be co-responsible together with Na+ in triggering oxidative and inflammatory kidney damage and increasing blood pressure. This indicates the importance of reducing the intake of both ions as a non-pharmacological preventive measure for the prevention and control of HTN. The role of ClC-K1 and ClC-5 channels as mediators of this process remains to be confirmed.
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Sonogenetics is an emerging synthetic biology technique that uses sound waves to activate mechanosensitive ion channel proteins on the cell surface to regulate cell behavior and function.Due to the widespread presence of mechanically sensitive ion channel systems in cells and the advantages of non-invasion,strong penetrability,high safety and high accuracy of sonogenetics technology,it has great development potential in basic biomedical research and clinical applications,especially in neuronal regulation,tumor mechanism research,sonodynamic therapy and hearing impairment.This review discusses the basic principles of sonogenetics,the development status of sonogenetics and its application in the prevention and treatment of noise-induced hearing loss,summarizes and analyzes the current challenges and future development direction,thus providing a reference for further research and development of sonogenetics in the field of military medicine.
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The unilateral biportal endoscopic spinal surgery(UBE)technique is an emerging endoscopic technique,mainly used as treatment for lumbar degenerative disease.The procedure is characterized by two working channels,one being endoscopic,the second to be employed as an operating channel.Through the use of such dual-channel-technology,it allows the operating instruments to be unrestricted in size.Therefore,it is a highly efficient surgical technique for minimally invasive spinal surgery(MISS).However,the clinical complications of UBE technology must be taken into consideration.Possible side effects include dural injury,epidural hematoma,occult blood loss,postoperative headache,nerve root injury and insufficient decompression.This article reviews the causes,prevention and management of UBE-related complications.
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ObjectiveIn recent years, the negative impact of microgravity on astronauts’ nervous systems has received widespread attention. The repetitive transcranial magnetic stimulation (rTMS) technology has shown significant positive effects in the treatment of neurological and psychiatric disorders. The potential benefits of combined frequency stimulation (CFS) which combines different frequency stimulation patterns in ameliorating neurological dysfunctions induced by the microgravity environment, still require in-depth investigation. Exploring the therapeutic effects and electrophysiological mechanisms of CFS in improving various neurological disorders caused by microgravity holds significant importance for neuroscience and the clinical application of magnetic stimulation. MethodsThis study employed 40 C57BL/6 mice, randomly divided into 5 groups: sham group, hindlimb unloading (HU) group, 10 Hz group, 20 Hz group, and combined frequency stimulation (10 Hz+20 Hz, CFS) group. Mice in all groups except the sham group received 14 d of simulated microgravity conditions along with 14 d of repetitive transcranial magnetic stimulation. The effects of CFS on negative emotions and spatial cognitive abilities were assessed through sucrose preference tests and water maze experiments. Finally, patch-clamp techniques were used to record action potentials, resting membrane potentials, and ion channel dynamics of granule neurons in the hippocampal dentate gyrus (DG) region. ResultsCompared to the single-frequency stimulation group, behavioral results indicated that the combined frequency stimulation (10 Hz+20 Hz) significantly improved cognitive impairments and negative emotions in simulated microgravity mice. Electrophysiological experiments revealed a decrease in excitability of granule neurons in the hippocampal DG region after HU manipulation, whereas the combined frequency stimulation notably enhanced neuronal excitability and improved the dynamic characteristics of voltage-gated Na+ and K+ channels. ConclusionThe repetitive transcranial magnetic stimulation with combined frequencies (10 Hz+20 Hz) effectively ameliorates cognitive impairments and negative emotions in simulated microgravity mice. This improvement is likely attributed to the influence of combined frequency stimulation on neuronal excitability and the dynamic characteristics of Na+ and K+ channels. Consequently, this study holds the promise to provide a theoretical basis for alleviating cognitive and emotional disorders induced by microgravity environments.
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Polyunsaturated fatty acids (PUFAs) have diverse health-promoting effects, such as potentially protecting in immune, nervous, and cardiovascular systems by targeting a variety of sites, including most ion channels. Voltage-gated potassium channels of the KV7 family and large-conductance Ca2+- and voltage-activated K+ (BKCa) channels are expressed in many tissues, therefore, their physiological importance is evident from the various disorders linked to dysfunctional KV7 channels and BKCa channels. Thus, it is extremely important to learn how potassium channels are regulated by PUFAs. The aim of this review is to provide an overview of the effects of PUFAs on KV7 channels and BKCa channels functions, as well as the mechanisms underlying these effects. In summarizing reported effects of PUFAs on KV7 and BKCa channels mediated currents, we generally conclude that PUFAs increase the current amplitude, meanwhile, differential molecular and biophysical mechanisms are associated with the current increase. In KV7 channels the currents increasement are associated with a shift in the voltage dependence of channel opening and increased maximum conductance in KV7 channels, while in BKCa channels, they are associated with destabilization the pore domain closed conformation. Furthermore, PUFA effects are influenced by auxiliary subunits of KV7 and BKCa channels, associate with channels in certain tissues. although findings are conflicting. A better understanding of how PUFAs regulate KV7 and BKCa channels may offer insight into their physiological regulation and may lead to new therapeutic strategies and approaches.
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AIM:To investigate the influence of fat mass and obesity-associated(Fto)gene on the aberrant contraction of aortic smooth muscle in diabetes mellitus(DM)mice,and to explore the mechanism of Fto gene underlying the calcium regulation.METHODS:Smooth muscle-specific Fto gene knockout(FtoSMKO)mice were generated using Cre-loxP technology.The experiment involved 3 groups of mice:wild-type(WT)group,DM model group and FtoSMKO-DM group,with 15 mice in each group.In DM group and FtoSMKO-DM group,type 1 DM was induced by intraperitoneal injec-tion of streptozotocin.The mice in WT group were injected with equal volume of citric acid-sodium citrate buffer solution.The influences of different drugs on the contraction responses of aortic smooth muscle in mice were analyzed using a multi-myograph system.The expression level of FTO protein in the aortic tissues was detected by Western blot.RESULTS:(1)Compared with WT mice,the expression levels of FTO protein in the aortic tissues of DM mice were significantly in-creased(P＜0.01).(2)The expression level of FTO protein in smooth muscle was significantly decreased after knockout of Fto gene(P＜0.01).Compared with WT group,the mice in DM group exhibited a significant decrease in body weight and a marked increase in fasting blood glucose level(P＜0.05).There were no noticeable differences in body weight or fasting blood glucose level between FtoSMKO-DM group and DM group(P＞0.05).(3)The contraction responses of aortic smooth muscle in DM group were substantially increased by phenylephrine compared with WT group.Specifically,vaso-constriction responses mediated by non-L-type calcium channels and store-operated calcium channels(SOCC)were signifi-cantly enhanced in DM group.In addition,the responses mediated by inositol 1,4,5-trisphosphate receptors(IP3R),which facilitate calcium release from the sarcoplasmic reticulum,were significantly enhanced.However,the responses mediated by caffeine-activated ryanodine receptors(RyR),which also facilitate calcium release from the sarcoplasmic re-ticulum,were significantly inhibited(P＜0.05).(4)Compared with DM group,the phenylephrine-induced contraction re-sponses of aortic smooth muscle in FtoSMKO-DM group were greatly weakened(P＜0.05).In particular,the vasoconstriction responses mediated by non-L-type calcium channels and SOCC in FtoSMKO-DM group were greatly suppressed(P＜0.05),while those mediated by caffeine-activated RyR were dramatically boosted(P＜0.05).However,IP3R-mediated responses were not affected(P＞0.05).CONCLUSION:Smooth muscle-specific Fto gene knockout suppresses contractile hyperre-sponsiveness in the aortic smooth muscle of DM mice,which may be attributed to involvement of FTO protein in calcium regulation in the vascular smooth muscle.
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AIM:To investigate the role of ClC-3 chloride channel in the promotion of radio sensitization of na-sopharyngeal carcinoma CNE-2Z cells by dihydroartemisinin(DHA).METHODS:MTT was used to detect the inhibito-ry effect of DHA on the viability of CNE-2Z cells and normal nasopharyngeal epithelial NP69-SV40T cells,the radio sensi-tization effect of DHA on CNE-2Z cells was detected by cloning assay,the expression of ClC-3 protein was detected by Western blot,the expression of ClC-3 protein was down-regulated by siRNA technology,and the chlorine current of cells was recorded by whole cell patch-clamp technology.RESULTS:(1)Compared with NP69-SV40T cells,DHA selective-ly inhibited the proliferation of CNE-2Z cells,with IC10 values of(13.020±4.831)μmol/L and(5.244±1.050)μmol/L,respectively(P＜0.01).(2)The results of clonal formation experiments showed that DHA had a radio sensitizing effect on CNE-2Z cells,with a radio sensitization ratio of 1.9.(3)DHA could activate the chlorine channel of CNE-2Z cells and produce an outward chlorine current,but had no effect on the chlorine channel of NP69-SV40T cells.(4)DHA promoted the expression of ClC-3 chloric channel protein in CNE-2Z cells(P＜0.01).(5)Chlorine channel blocker NPPB could in-hibit the radio sensitizing effect of DHA on CNE-2Z cells by 1.84 times,and also inhibited the chlorine current activated by DHA.(6)the down-regulation of CNE-2Z ClC-3 protein could inhibit the radio sensitization effect of DHA on CNE-2Z cells by 4.19 times,and the activation of chlorine current by DHA on CNE-2Z cells was no longer produced.CONCLU-SION:DHA has a radio sensitizing effect on nasopharyngeal carcinoma CNE-2Z cells,which is likely to be related to the activation of ClC-3 chloride channel.
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Objective:To investigate the relation between rs2298771 genotype in voltage-gated sodium channels 1A ( SCN1A) polymorphism and antiepileptic drug (AED) response in children with epilepsy. Methods:Sixty-two children with epilepsy admitted to Department of Neurology, Zhangjiakou First Hospital from June 2022 to December 2023 were divided into AED response group and AED resistance group ( n=31) according to their response to AED. In addition, 31 children with pharyngitis or mild gastroenteritis admitted to Department of Pediatrics at the same period were selected as control group. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to analyze the rs2298771 genotype in SCN1A polymorphism, and differences in rs2298771 genotype and allele in SCN1A polymorphism were compared among the 3 groups. Relation between rs2298771 genotype in SCN1A polymorphism and AED response was analyzed. Multivariate Logistic regression was used to analyze the influencing factors for AED response in children with epilepsy. Results:(1) Significant differences in type of first seizure and AEDs were noted between AED response group and AED resistance group ( P<0.05); compared with the AED resistance group, the AED response group had significantly lower seizure frequency, significantly longer duration after last seizure, and statistically higher proportions of children with normal EEG or with one kind of AED ( P?0.05). (2) Compared with the control group and AED response group, the AED resistance group had significantly higher rs2298771 GC genotype and G allele, and statistically lower rs2298771 AA genotype and A allele in SCN1A polymorphism ( P?0.05). (3) In the AED response group, rs2298771 AA and AG genotype in SCN1A polymorphism were positively correlated with levetiracetam ( P?0.05); in AED resistance group, rs2298771 AG genotype in SCN1A polymorphism was positively correlated with topiramate and valproic acid ( P<0.05). (4) Multivariate Logistic regression analysis showed that duration after last seizure ( OR=3.249, 95% CI=1.097-9.621, P=0.033), rs2298771 genotype in SCN1A polymorphism ( OR=9.660, 95% CI=4.680-19.970, P=0.011) and seizure frequency ( OR=0.160, 95% CI=0.032-0.804, P=0.026) were independent influencing factors for AED response in children with epilepsy. Conclusion:Epilepsy children with shorter duration after last seizure, rs2298771 GG genotype in SCN1A polymorphism, and high seizure frequency are susceptible to AED resistance; especially, AG genotype is correlated with topiramate and valproic acid.
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Resumo Fundamento A hipertensão arterial sistêmica é um fator de risco para disfunções cardíacas, renais e metabólicas. A busca por novas estratégias para prevenir e tratar doenças cardiovasculares levou à síntese de novas N-acilidrazonas para produzir efeito anti-hipertensivo. Os receptores de adenosina são um alvo alternativo para reduzir a pressão arterial devido à sua ação vasodilatadora e propriedades antioxidantes, que podem reduzir o estresse oxidativo característico da hipertensão arterial sistêmica. Objetivo Avaliar o perfil anti-hipertensivo de novos compostos contendo selênio desenvolvidos para melhorar sua interação com os receptores de adenosina. Métodos Foi avaliada a reatividade vascular, registrando-se a tensão isométrica da aorta torácica pré-contraída de ratos Wistar machos após exposição a concentrações crescentes de cada derivado (0,1 a 100 μM). Para investigar o efeito anti-hipertensivo em ratos espontaneamente hipertensos, foram determinadas a pressão arterial sistólica, pressão arterial diastólica, pressão arterial média e a frequência cardíaca após administração intravenosa de 10 e 30 μmol/kg do composto selecionado LASSBio-2062. Resultados Os compostos denominados LASSBio-2062, LASSBio-2063, LASSBio-2075, LASSBio-2076, LASSBio-2084, LASSBio-430, LASSBio-2092 e LASSBio-2093 promoveram vasodilatação com concentrações efetivas médias de 15,5 ± 6,5; 14,6 ± 2,9; 18,7 ± 9,6; 6,7 ± 4,1; > 100; 6,0 ± 3,6; 37,8 ± 11,8; e 15,9 ± 5,7 μM, respectivamente. O LASSBio-2062 (30 μmol/kg) reduziu a pressão arterial média em ratos espontaneamente hipertensos de 124,6 ± 8,6 para 72,0 ± 12,3 mmHg (p < 0,05). A ativação do receptor de adenosina subtipo A3 e dos canais de potássio parece estar envolvida no efeito anti-hipertensivo do LASSBio-2062. Conclusões O novo agonista do receptor de adenosina e ativador dos canais de potássio é um potencial agente terapêutico para o tratamento da hipertensão arterial sistêmica.
Abstract Background Systemic arterial hypertension is a risk factor for cardiac, renal, and metabolic dysfunction. The search for new strategies to prevent and treat cardiovascular diseases led to the synthesis of new N-acylhydrazones to produce antihypertensive effect. Adenosine receptors are an alternative target to reduce blood pressure because of their vasodilatory action and antioxidant properties, which may reduce oxidative stress characteristic of systemic arterial hypertension. Objective To evaluate the antihypertensive profile of novel selenium-containing compounds designed to improve their interaction with adenosine receptors. Methods Vascular reactivity was evaluated by recording the isometric tension of pre-contracted thoracic aorta of male Wistar rats after exposure to increasing concentrations of each derivative (0.1 to 100 μM). To investigate the antihypertensive effect in spontaneously hypertensive rats, systolic, diastolic, and mean arterial pressure and heart rate were determined after intravenous administration of 10 and 30 μmol/kg of the selected compound LASSBio-2062. Results Compounds named LASSBio-2062, LASSBio-2063, LASSBio-2075, LASSBio-2076, LASSBio-2084, LASSBio-430, LASSBio-2092, and LASSBio-2093 promoted vasodilation with mean effective concentrations of 15.5 ± 6.5; 14.6 ± 2.9; 18.7 ± 9.6; 6.7 ± 4.1; > 100; 6.0 ± 3.6; 37.8 ± 11.8; and 15.9 ± 5.7 μM, respectively. LASSBio-2062 (30 μmol/kg) reduced mean arterial pressure in spontaneously hypertensive rats from 124.6 ± 8.6 to 72.0 ± 12.3 mmHg (p < 0.05). Activation of adenosine receptor subtype A3 and potassium channels seem to be involved in the antihypertensive effect of LASSBio-2062. Conclusions The new agonist of adenosine receptor and activator of potassium channels is a potential therapeutic agent to treat systemic arterial hypertension.
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Background Astrocytes Ca2+ signaling play a central role in the modulation of neuronal function. Activation of metabotropic glutamate receptors (mGluR) by glutamate released during an increase in synaptic activity triggers coordinated Ca2+ signals in astrocytes. Importantly, astrocytes express the Ca2+-dependent nitric oxide (NO)-synthe-tizing enzymes eNOS and nNOS, which might contribute to the Ca2+ signals by triggering Ca2+ influx or ATP release through the activation of connexin 43 (Cx43) hemichannels, pannexin-1 (Panx-1) channels or Ca2+ homeostasis modulator 1 (CALHM1) channels. Hence, we aim to evaluate the participation of NO in the astrocytic Ca2+ signaling initiated by stimulation of mGluR in primary cultures of astrocytes from rat brain cortex. Results Astrocytes were stimulated with glutamate or t-ACPD and NO-dependent changes in [Ca2+]i and ATP release were evaluated. In addition, the activity of Cx43 hemichannels, Panx-1 channels and CALHM1 channels was also analyzed. The expression of Cx43, Panx-1 and CALHM1 in astrocytes was confirmed by immunofluorescence analysis and both glutamate and t-ACPD induced NO-mediated activation of CALHM1 channels via direct S-nitrosylation, which was further confirmed by assessing CALHM1-mediated current using the two-electrode voltage clamp technique in Xenopus oocytes. Pharmacological blockade or siRNA-mediated inhibition of CALHM1 expression revealed that the opening of these channels provides a pathway for ATP release and the subsequent purinergic receptordependent activation of Cx43 hemichannels and Panx-1 channels, which further contributes to the astrocytic Ca2+ signaling. Conclusions Our findings demonstrate that activation of CALHM1 channels through NO-mediated S-nitrosylation in astrocytes in vitro is critical for the generation of glutamate-initiated astrocytic Ca2+ signaling.
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Abstract The effect of peptide toxins on voltage-gated ion channels can be reliably assessed using electrophysiological assays, such as the patch-clamp technique. However, much of the toxinological research done in Central and South America aims at purifying and characterizing biochemical properties of the toxins of vegetal or animal origin, lacking electrophysiological approaches. This may happen due to technical and infrastructure limitations or because researchers are unfamiliar with the techniques and cellular models that can be used to gain information about the effect of a molecule on ion channels. Given the potential interest of many research groups in the highly biodiverse region of Central and South America, we reviewed the most relevant conceptual and methodological developments required to implement the evaluation of the effect of peptide toxins on mammalian voltage-gated ion channels using patch-clamp. For that, we searched MEDLINE/PubMed and SciELO databases with different combinations of these descriptors: "electrophysiology", "patch-clamp techniques", "Ca2+ channels", "K+ channels", "cnidarian venoms", "cone snail venoms", "scorpion venoms", "spider venoms", "snake venoms", "cardiac myocytes", "dorsal root ganglia", and summarized the literature as a scoping review. First, we present the basics and recent advances in mammalian voltage-gated ion channel's structure and function and update the most important animal sources of channel-modulating toxins (e.g. cnidarian and cone snails, scorpions, spiders, and snakes), highlighting the properties of toxins electrophysiologically characterized in Central and South America. Finally, we describe the local experience in implementing the patch-clamp technique using two models of excitable cells, as well as the participation in characterizing new modulators of ion channels derived from the venom of a local spider, a toxins' source less studied with electrophysiological techniques. Fostering the implementation of electrophysiological methods in more laboratories in the region will strengthen our capabilities in many fields, such as toxinology, toxicology, pharmacology, natural products, biophysics, biomedicine, and bioengineering.
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Background: Effective communication is key to ensuring that barriers to childhood vaccination are tackled. Most times the source and content of information fails to deliver the necessary information needed to make proper decision children’s vaccination. This study explored the perception of communication messages and the different channels used in delivering messages on vaccination among parents/caregivers in Anambra State, Nigeria. Methods: A descriptive cross-sectional study was conducted in Anambra State, Nigeria among parents/caregivers with children aged 0-59 months. A multistage sampling method was used. Questionnaire was used for data collection and analyzed using IMB SPSS version 23. Chi square test was used for association at p<0.05. Results: Findings show that the overall awareness and knowledge was very high 306 (95.6%). Majority 216 (67.50%) of the respondents only receive the key immunization messages during campaigns. Most preferred channel of delivery was through religious groups 273 (85.3%). followed by town announcers 270 (84.4%). Overall, 175 (54.7%) were positive on messages given during Immunization campaigns. Higher proportion agreed that immunization messages are better reinforced if both parents are targeted 309 (98.6%). There were statistically significant association of overall awareness and knowledge with age p=0.043, gender p=0.006, educational level <0.001 and occupation p=0.001. There were no statistically significant association of overall perception with characteristics of respondents. Conclusions: Parents/caregivers’ perceptions of immunization messages can influence social change and increase immunization uptake. Both parents of the children should be targeted whenever immunization messages are to be disseminated.
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La hipertensión arterial pulmonar se caracteriza por una presión arterial pulmonar media y resistencia vascular pulmonar elevadas y remodelado patológico de las arterias pulmonares. La entrada de calcio desde el espacio extracelular al intracelular a través de canales dependientes e independientes de voltaje juega un rol fundamental en el aumento de la contractilidad de las arterias pulmonares y la pérdida de regulación del comportamiento proliferativo de las células de las distintas capas de la pared de las arterias pulmonares. De esta manera, estos canales contribuyen con la vasoconstricción exacerbada de las arterias pulmonares y a su remodelado patológico. El objetivo de esta revisión es recapitular la evidencia obtenida desde modelos celulares y animales respecto a la contribución de los principales canales de calcio de membrana plasmática en estos mecanismos fisiopatológicos claves en el desarrollo de la hipertensión pulmonar, discutiendo su valor potencial como diana farmacológica para terapias presentes y futuras.
Pulmonary arterial hypertension is characterized by increased mean pulmonary arterial pressure, resistance, and pathological remodeling of pulmonary arteries. Calcium entry from the extracellular to the intracellular space through voltage-dependent and -independent channels play a major role in the increase of contractility of pulmonary arteries and in the loss of regulation of the proliferative behavior of the cells from the different layers of the pulmonary arterial wall. In doing so, these channels contribute to enhanced vasoconstriction of pulmonary arteries and their pathological remodeling. This review aims to summarize the evidence obtained from animal and cellular models regarding the involvement of the main plasma membrane calcium channels in these key pathophysiological processes for pulmonary arterial hypertension, discussing the potential value as pharmacological targets for therapies in the present and the future.
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Humans , Calcium Channels/drug effects , Calcium Channels/physiology , Hypertension, Pulmonary/physiopathology , Hypertension, Pulmonary/drug therapy , Pulmonary Artery/drug effects , Pulmonary Artery/physiopathology , Vasoconstriction/drug effects , Vasoconstriction/physiology , Calcium Channel Blockers/therapeutic use , Calcium Channel Blockers/pharmacology , Signal Transduction/drug effects , Calcium Signaling/drug effects , Calcium Signaling/physiology , AnimalsABSTRACT
Objectives: Centrally-acting antitussives with inhibitory effects on G protein-coupled inwardly rectifying potassium (GIRK) channels have been shown to also inhibit methamphetamine-induced hyperactivity in mice. In this study, we examined if cloperastine, which is the most potent inhibitor of the GIRK channels among antitussives, is sensitive to the expression levels of GIRK channels in the brain of methamphetaminetreated mice. Materials and Methods: The brain tissues have been removed and the total RNA has been extracted from tissues. The mRNA levels were evaluated using semiquantitative reverse transcription-polymerase chain reaction. Results: The concentration levels of the mRNA of GIRK channels within the ventral midbrain of methamphetamine-treated mice increased as compared with that in control and cloperastine reduced an upregulation in GIRK2, one of the subunits of the GIRK channels, by the injection of methamphetamine. Conclusion: These findings suggest that cloperastine might ameliorate hyperactivity by inhibiting the GIRK channels in the brain.
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OBJECTIVE@#To investigate the effect of ferulic acid, a natural compound, on pancreatic beta cell viability, Ca2+ channels, and insulin secretion.@*METHODS@#We studied the effects of ferulic acid on rat insulinoma cell line viability using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide viability assay. The whole-cell patch-clamp technique and enzyme-linked immunosorbent assay were also used to examine the action of ferulic acid on Ca2+ channels and insulin secretion, respectively.@*RESULTS@#Ferulic acid did not affect cell viability during exposures up to 72 h. The electrophysiological study demonstrated that ferulic acid rapidly and concentration-dependently increased L-type Ca2+ channel current, shifting its activation curve in the hyperpolarizing direction with a decreased slope factor, while the voltage dependence of inactivation was not affected. On the other hand, ferulic acid have no effect on T-type Ca2+ channels. Furthermore, ferulic acid significantly increased insulin secretion, an effect inhibited by nifedipine and Ca2+-free extracellular fluid, confirming that ferulic acid-induced insulin secretion in these cells was mediated by augmenting Ca2+ influx through L-type Ca2+ channel. Our data also suggest that this may be a direct, nongenomic action.@*CONCLUSION@#This is the first electrophysiological demonstration that acute ferulic acid treatment could increase L-type Ca2+ channel current in pancreatic β cells by enhancing its voltage dependence of activation, leading to insulin secretion.
Subject(s)
Rats , Animals , Insulin Secretion , Insulin/pharmacology , Insulin-Secreting Cells/metabolism , Coumaric Acids/metabolism , Calcium/metabolismABSTRACT
【Objective】 To explore the safety and efficacy of a novel endoscopic two-wire guided dilation in the creation of channels in percutaneous nephrolithotomy (PCNL). 【Methods】 Clinical records of 180 patients undergoing PCNL during Oct.2020 and Oct.2022 were retrospectively analyzed. The patients were divided into three groups, 60 in AMD group (fascial amplatz dilation), 60 in OSD group (one shot dilation) and 60 in END group (endoscopic dilation). Time to establish channels, operating time, failure of access, stone clearance rate, drop in hemoglobin, embolization rate, fever rate, blood transfusion rate and postoperative hospitalization were compared among the three groups. 【Results】 There were no significant differences in the general data among the three groups (P>0.05). Compared with AMD and OSD groups, END group needed significantly reduced time to establish the first channel [(5.6±0.8) min vs. (4.9±1.4) min vs. (4.2±0.5) min, (P<0.05)] . Compared with OSD group, END and AMD groups had significantly more hemoglobin drop [(14.0±17.6) g/L vs. (19.4±12.6) g/L vs. (10.2±6.8) g/L, (P<0.05)] . There were no significant differences in terms of failure of establishing channels, operating time, stone clearance rate, embolization rate, fever rate, blood transfusion rate and postoperative hospitality. Four patients needed selective renal artery embolization (1 case in AMD group and 3 in OSD group). No serious complications such as organ injuries, septic shock or death occurred. 【Conclusion】 Endoscopic two-wire guided dilation is simple, with few complications and good application value.
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Weightlessness in the space environment affects astronauts' learning memory and cognitive function. Repetitive transcranial magnetic stimulation has been shown to be effective in improving cognitive dysfunction. In this study, we investigated the effects of repetitive transcranial magnetic stimulation on neural excitability and ion channels in simulated weightlessness mice from a neurophysiological perspective. Young C57 mice were divided into control, hindlimb unloading and magnetic stimulation groups. The mice in the hindlimb unloading and magnetic stimulation groups were treated with hindlimb unloading for 14 days to establish a simulated weightlessness model, while the mice in the magnetic stimulation group were subjected to 14 days of repetitive transcranial magnetic stimulation. Using isolated brain slice patch clamp experiments, the relevant indexes of action potential and the kinetic property changes of voltage-gated sodium and potassium channels were detected to analyze the excitability of neurons and their ion channel mechanisms. The results showed that the behavioral cognitive ability and neuronal excitability of the mice decreased significantly with hindlimb unloading. Repetitive transcranial magnetic stimulation could significantly improve the cognitive impairment and neuroelectrophysiological indexes of the hindlimb unloading mice. Repetitive transcranial magnetic stimulation may change the activation, inactivation and reactivation process of sodium and potassium ion channels by promoting sodium ion outflow and inhibiting potassium ion, and affect the dynamic characteristics of ion channels, so as to enhance the excitability of single neurons and improve the cognitive damage and spatial memory ability of hindlimb unloading mice.
Subject(s)
Animals , Mice , Transcranial Magnetic Stimulation , Hindlimb Suspension , Neurons , Cognitive Dysfunction , BrainABSTRACT
This study aimed to investigate the effects of Erxian Decoction(EXD)-containing serum on the proliferation and osteogenic differentiation of MC3T3-E1 cells under oxidative stress through BK channels. The oxidative stress model was induced in MC3T3-E1 cells by H_2O_2, and 3 mmol·L~(-1) tetraethylammonium(TEA) chloride was used to block the BK channels in MC3T3-E1 cells. MC3T3-E1 cells were divided into a control group, a model group, an EXD group, a TEA group, and a TEA+EXD group. After MC3T3-E1 cells were treated with corresponding drugs for 2 days, 700 μmol·L~(-1) H_2O_2 was added for treatment for another 2 hours. CCK-8 assay was used to detect cell proliferation activity. The alkaline phosphatase(ALP) assay kit was used to detect the ALP activity of cells. Western blot and real-time fluorescence-based quantitative PCR(RT-qPCR) were used to detect protein and mRNA expression, respectively. Alizarin red staining was used to detect the mineralization area of osteoblasts. The results showed that compared with the control group, the model group showed significantly blunted cell proliferation activity and ALP activity, reduced expression of BK channel α subunit(BKα), collagen Ⅰ(COL1), bone morphogenetic protein 2(BMP2), osteoprotegerin(OPG), and phosphorylated Akt, decreased mRNA expression levels of Runt-related transcription factor 2(RUNX2), BMP2, and OPG, and declining area of calcium nodules. EXD-containing serum could significantly potentiate the cell proliferation activity and ALP activity, up-regulate the protein expression of BKα, COL1, BMP2, OPG, and phosphorylated Akt, and forkhead box protein O1(FoxO1), promote the mRNA expression of RUNX2, BMP2, and OPG, and enlarge the area of calcium nodules. However, BK channel blockage by TEA reversed the effects of EXD-containing serum in promoting the protein expression of BKα, COL1, BMP2, OPG, and phosphorylated Akt and FoxO1, increasing the mRNA expression of RUNX2, BMP2, and OPG, and enlarging the area of calcium nodules. EXD-containing serum could improve the proliferation activity, osteogenic differentiation, and mineralization ability of MC3T3-E1 cells under oxidative stress, which might be related to the regulation of BK channels and downstream Akt/FoxO1 signaling pathway.
Subject(s)
Osteogenesis , Core Binding Factor Alpha 1 Subunit/pharmacology , Large-Conductance Calcium-Activated Potassium Channels/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , Calcium/metabolism , Cell Differentiation , RNA, Messenger/metabolism , Cell Proliferation , OsteoblastsABSTRACT
Objective To explore the molecular mechanism of prolonged atrial repolarization in rats with reperfusion atrial arrhythmia.Methods Sixteen Langendorff isolated heart perfusion models made by male SD rats were randomly divided into control group(group C,n = 8)and hypothermic ischemia-reperfusion group(group IR,n = 8).According to the occurrence of atrial arrhythmia after reperfusion,group IR was further subdivided into reperfusion non-atrial arrhythmia subgroup(group N-RAA)and reperfusion atrial arrhythmia subgroup(group R-AA).Group C was perfused with 37℃K-H solution for 120 min.In group IR,the isolated heart was perfused with 37℃K-H solution for 30 min and stopped,and the isolated heart was perfused with 4℃Thomas solution(20 mL/kg)for 60 mins.When the heart stopped for 30 mins,the isolated heart was perfused with a half dose of 4℃Thomas solution(10℃).During cardioplegia,the isolated heart was protected by low temperature Thomas solution(4℃),and then reperfused for 30 mins with 37℃K-H solution.The monophasic action potential(MAP)of the right atrium was recorded at balanced perfusion for 30 mins(T0),balanced perfusion for 105 mins in group C/reperfusion for 15 mins in group IR(T1)and balanced perfusion for 120 mins in group C/reperfusion for 30 min in group IR(T2);The duration of 50%and 90%repolarization of monophasic action potential(MAPD50 and MAPD90)was measured.After electrophysiological monitoring,the expression of Kir2.1 and CaMKⅡ in right atrium was detected by Western blot.Results Compared with T0,MAPD50 and MAPD90 at T1 and T2 were significantly prolonged in group R-AA(P<0.05),and MAPD90 at T1 and T2 in group R-NAA and group R-AA were significantly longer than those in group C(P<0.05).Compared with group R-NAA,MAPD50 and MAPD90 in group R-AA were significantly prolonged at T1 and T2(P<0.05).The results of Western blot showed that the expression of Kir2.1 in group R-NAA and group R-AA was significantly lower than that in group C(P<0.05),and that in group R-AA was significantly lower than that in group R-NAA(P<0.05).The expression of CaMKⅡ in group R-NAA and group R-AA was significantly higher than that in group C(P<0.05),and the expression of CaMKⅡ in group R-AA was significantly higher than that in group R-NAA.Conclusion The prolonged duration of atrial repolarization in rats with hypothermic ischemia-reperfusion atrial arrhythmia may be related to the down-regulation of Kir2.1 expression and the up-regulation of CaMKⅡ expression.
ABSTRACT
Objective To explore the regulatory effect of miR-26b-5p on PI3K/PIP3 signaling path-way and its effect on L-type calcium channel of atrial cardiomyocytes in rats with ischemic ar-rhythmia.Methods A total of 72 SD rats were randomly divided into sham operation group,mod-el group,LY294002 group,negative control group,overexpression group and combination group,with 12 rats in each group.In 24 h after corresponding intervention,rat model of ischemic arrhyth-mia was established in the other groups except the sham operation group(only thoracotomy but without ligation).During the modeling process,arrhythmia indexes were detected in each group,and Curtis-Walker scoring was used for arrhythmia score.Fluorescence quantitative PCR was em-ployed to detect the expression of miR-26b-5p in atrial myocardiocytes,whole-cell patch-clamp technique was used to record the ICa-L of atrial myocardiocytes,and Western blotting was applied to measure the expression of CACNA1C,calmodulin and PI3K/PIP3 pathway related proteins.Re-sults Compared with the model group,the number of left ventricular preventricular contrac-tions,duration of ventricular tachycardia,duration of ventricular fibrillation,arrhythmia score,ab-solute value of ICa-L peak density of atrial myocardiocytes,and expression levels of CACNA1C and calmodulin were significantly increased,and the levels of miR-26b-5p,p-PI3K,PIP3 and p-Akt were obviously decreased in the LY294002 group(P＜0.05).While the overexpression group had decreased number of left ventricular preventricular contractions,shorter duration of ventricular tachycardia,shorter duration of ventricular fibrillation,lower arrhythmia score,reduced absolute value of ICa-L peak density,and lower expression levels of CACNA1C and calmodulin,and in-creased levels of miR-26b-5p,p-PI3K,PIP3 and p-Akt than the model group(P＜0.05).The number of left ventricular preventricular contractions,duration of ventricular tachycardia,dura-tion of ventricular fibrillation,arrhythmia score,absolute value of ICa-L peak density and expres-sion levels of CACNA1C and calmodulin were significantly increased,and the expression of p-PI3K,PIP3 and p-Akt were obviously decreased(0.82±0.08 vs 1.09±0.11,0.91±0.09 vs 1.17± 0.11,0.94±0.09 vs 1.20±0.12,P＜0.05)in the combination group than the overexpression group.Conclusion Overexpression of miR-26b-5p may block the L-type calcium channel in atrial myocardiocytes in ischemic arrhythmia rats by activating PI3K/PIP3 related signaling pathway,and thus improve the performance of arrhythmia in rats.