RESUMO
The risk of plague epidemics and relapse of various types of plague foci persists in Inner Mongolia Autonomous Region. For Marmota sibirica plague foci, the animal plague has not been found but antibody has been detected positive. Nowadays, Marmota sibirica has been increasing in population and distribution in China. In bordering countries Mongolia and Russia, the animal plague has been continuously prevalent. For Spermophilus dauricus plague foci, the animal plague has been taken place now and then. Compared to the above foci, the animal plague is most prevalent in Meriones unguiculatus plague foci and frequently spread to humans. Due to higher strain virulence and historical disaster in Marmota sibirica plague foci and Spermophilus dauricus plague foci, plague prevention and control should be strengthened on these foci. In addition to routine surveillance, epidemic dynamics need to be further monitored in these two foci, in order to prevent their relapse and spread to humans.
Assuntos
Animais , Humanos , China/epidemiologia , Epidemias , Peste/prevenção & controle , Prevalência , Sciuridae , Yersinia pestisRESUMO
To scientifically evaluate the intervention effect of Chinese medicine preventive administration(combined use of Huo-xiang Zhengqi Oral Liquid and Jinhao Jiere Granules) on community population in the case of coronavirus disease 2019(COVID-19), a large cohort, prospective, randomized, and parallel-controlled clinical study was conducted. Total 22 065 subjects were included and randomly divided into 2 groups. The non-intervention group was given health guidance only, while the traditional Chinese medicine(TCM) intervention group was given two coordinated TCM in addition to health guidance. The medical instructions were as follows. Huoxiang Zhengqi Oral Liquid: oral before meals, 10 mL/time, 2 times/day, a course of 5 days. Jinhao Jiere Granules: dissolve in boiling water and take after meals, 8 g/time, 2 times/day, a course of 5 days, followed up for 14 days, respectively. The study found that with the intake of medication, the incidence rate of TCM intervention group was basically maintained at a low and continuous stable level(0.01%-0.02%), while the non-intervention group showed an overall trend of continuous growth(0.02%-0.18%) from 3 to 14 days. No suspected or confirmed COVID-19 case occurred in either group. There were 2 cases of colds in the TCM intervention group and 26 cases in the non-intervention group. The incidence of colds in the TCM intervention group was significantly lower(P<0.05) than that in the non-intervention group. In the population of 16-60 years old, the incidence rate of non-intervention and intervention groups were 0.01% and 0.25%, respectively. The difference of colds incidence between the two groups was statistically significant(P<0.05). In the population older than 60 years old, they were 0.04% and 0.21%, respectively. The incidence of colds in the non-intervention group was higher than that in the intervention group, but not reaching statistical difference. The protection rate of TCM for the whole population was 91.8%, especially for the population of age 16-60(95.0%). It was suggested that TCM intervention(combined use of Huoxiang Zhengqi Oral Liquid and Jinhao Jiere Granules) could effectively protect community residents against respiratory diseases, such as colds, which was worthy of promotion in the community. In addition, in terms of safety, the incidence of adverse events and adverse reactions in the TCM intervention group was relatively low, which was basically consistent with the drug instructions.
Assuntos
Adolescente , Adulto , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Betacoronavirus , Infecções por Coronavirus , Tratamento Farmacológico , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Pandemias , Pneumonia Viral , Tratamento Farmacológico , Estudos ProspectivosRESUMO
The aim of the present paper was to study the role of sodium calcium exchanger (NCX) in the generation of action potentials (APs) in cardiomyocytes during early developmental stage (EDS). The precisely dated embryonic hearts of C57 mice were dissected and enzymatically dissociated to single cells. The changes of APs were recorded by whole-cell patch-clamp technique before and after administration of NCX specific blockers KB-R7943 (5 μmol/L) and SEA0400 (1 μmol/L). The results showed that, both KB-R7943 and SEA0400 had potent negative chronotropic effects on APs of pacemaker-like cells, while such effects were only observed in some ventricular-like cardiomyocytes. The negative chronotropic effect of KB-R7943 on ventricular-like cardiomyocytes was accompanied by shortening of AP duration (APD), whereas such an effect of SEA0400 was paralleled by decrease in velocity of diastolic depolarization (Vdd). From embryonic day 9.5 (E9.5) to E10.5, the negative chronotropic effects of KB-R7943 and SEA0400 on ventricular-like APs of embryonic cardiomyocytes gradually disappeared. These results suggest that, in the short-term development of early embryo, the function of NCX may experience developmental changes as evidenced by different roles of NCX in autorhythmicity and APs generation, indicating that NCX function varies with different conditions of cardiomyocytes.
Assuntos
Animais , Camundongos , Potenciais de Ação , Cálcio/metabolismo , Miócitos Cardíacos/metabolismo , Sódio/metabolismo , Trocador de Sódio e Cálcio , Tioureia/farmacologiaRESUMO
The suspended magnetic moxibustion cupping therapy,as a specific moxibustion method which collects moxibustion,cupping,infrared and magnetic therapy into one,and integrates with the warming and heating effect of moxibustion,sucking effect of cups,and effect of infrared light energy and magnetic energy,is a particularly unique method for weight loss.This article introduces the basic situation and mechanism of suspended magnetic cupping therapy for weight loss.For pathogenesis of deficiency,phlegm,stagnation and cold in obesity,Shuang Long Xi Zhu (two dragons playing a ball) moxibustion,abdominal Jiu Gong (nine palaces) moxibustion,San Yang Kai Tai (auspicious beginning) moxibustion and Chang Long (long dragon) moxibustion were given respectively.This therapy has inspired the clinical idea of Chinese medicine for obesity.
RESUMO
Thymosin β4 (Tβ4) is a key factor in cardiac development, growth, disease, epicardial integrity, blood vessel formation and has cardio-protective properties. However, its role in murine embryonic stem cells (mESCs) proliferation and cardiovascular differentiation remains unclear. Thus we aimed to elucidate the influence of Tβ4 on mESCs. Target genes during mESCs proliferation and differentiation were detected by real-time PCR or Western blotting, and patch clamp was applied to characterize the mESCs-derived cardiomyocytes. It was found that Tβ4 decreased mESCs proliferation in a partial dose-dependent manner and the expression of cell cycle regulatory genes c-myc, c-fos and c-jun. However, mESCs self-renewal markers Oct4 and Nanog were elevated, indicating the maintenance of self-renewal ability in these mESCs. Phosphorylation of STAT3 and Akt was inhibited by Tβ4 while the expression of RAS and phosphorylation of ERK were enhanced. No significant difference was found in BMP2/BMP4 or their downstream protein smad. Wnt3 and Wnt11 were remarkably decreased by Tβ4 with upregulation of Tcf3 and constant β-catenin. Under mESCs differentiation, Tβ4 treatment did not change the expression of cardiovascular cell markers α-MHC, PECAM, and α-SMA. Neither the electrophysiological properties of mESCs-derived cardiomyocytes nor the hormonal regulation by Iso/Cch was affected by Tβ4. In conclusion, Tβ4 suppressed mESCs proliferation by affecting the activity of STAT3, Akt, ERK and Wnt pathways. However, Tβ4 did not influence the in vitro cardiovascular differentiation.
Assuntos
Animais , Camundongos , Ciclo Celular , Genética , Diferenciação Celular , Movimento Celular , Proliferação de Células , Relação Dose-Resposta a Droga , MAP Quinases Reguladas por Sinal Extracelular , Genética , Metabolismo , Regulação da Expressão Gênica , Proteínas Quinases JNK Ativadas por Mitógeno , Genética , Metabolismo , Células-Tronco Embrionárias Murinas , Biologia Celular , Metabolismo , Miócitos Cardíacos , Biologia Celular , Metabolismo , Proteína Homeobox Nanog , Genética , Metabolismo , Fator 3 de Transcrição de Octâmero , Genética , Metabolismo , Técnicas de Patch-Clamp , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-akt , Genética , Metabolismo , Proteínas Proto-Oncogênicas c-fos , Genética , Metabolismo , Proteínas Proto-Oncogênicas c-myc , Genética , Metabolismo , Fator de Transcrição STAT3 , Genética , Metabolismo , Transdução de Sinais , Timosina , FarmacologiaRESUMO
This study is to explore a new method of investigating molecular basis for electrophysiological properties of early fetal cardiomyocytes. Single embryonic cardiomyocytes of mouse early developmental heart (E10.5) were obtained by a collagenase B digestion approach. After recording spontaneous action potential using whole cell patch clamp technique, the single cell was picked by a glass micropipette, followed by a standard RT-PCR to explore the expression levels of several ion channel genes. Three phenotypes of cardiomyocytes were demonstrated with distinct properties: ventricular-like, atrial-like, and pacemaker-like action potentials. Ventricular-like and atrial-like cells were characterized with much negative maximum diastolic potential (MDP) and a higher V(max) (maximum velocity of depolarization) compared to pacemaker-like cells. MDP of ventricular-like cells was the most negative. In parallel, stronger expression of SCN5a, SCN1b and Kir2.1 were observed in ventricular-like and atrial-like cells compared to that of pacemaker-like cells, where Kir2.1 in ventricular-like cells was the most abundant. Cardiomyocytes with distinct electrophysiological properties had distinct gene expression pattern. Single cell RT-PCR combined with patch clamp technique could serve as a precise detector to analyze the molecular basis of the special electrophysiological characteristics of cardiomyocytes.
Assuntos
Animais , Feminino , Masculino , Camundongos , Fenômenos Eletrofisiológicos , Feto , Miócitos Cardíacos , Metabolismo , Fisiologia , Genética , Metabolismo , Técnicas de Patch-Clamp , Canais de Potássio Corretores do Fluxo de Internalização , Genética , Metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Subunidade beta-1 do Canal de Sódio Disparado por Voltagem , Genética , MetabolismoRESUMO
The aim of the present study was to investigate the influence of osmotic pressure on myocardial contractility and the possible mechanism. Electrical stimulation was used to excite papillary muscles of the left ventricle of Sprague-Dawley (SD) rats. The contractilities of myocardium in hyposmotic, isosmotic, and hyperosmotic perfusates were recorded. The influences of agonist and antagonist of the transient receptor potential vanilloid 4 (TRPV4) on the contractility of myocardium under hyposmotic, isosmotic and hyperosmotic conditions were observed. The results were as follows: (1) Compared with that under isosmotic condition (310 mOsm/L), the myocardial contractility was increased by 11.5%, 21.5% and 25.0% (P<0.05) under hyposmotic conditions when the osmotic pressure was at 290, 270 and 230 mOsm/L, respectively; and was decreased by 16.0%, 23.7% and 55.2% (P<0.05) under hyperosmotic conditions when the osmotic pressure was at 350, 370 and 390 mOsm/L, respectively. (2) When ruthenium red (RR), an antagonist of TRPV4, was added to the hyposmotic perfusate (270 mOsm/L), the positive inotropic effect of hyposmia was restrained by 36% (P<0.01); and when RR was added to the hyperosmotic perfusate (390 mOsm/L), the inhibitory effect of hyperosmia on myocardial contractility was increased by 56.1% (P<0.01). (3) When 4-α-phorbol-12,13-didecanoate (4α-PDD), an agonist of TRPV4, was added to the isosmotic perfusate (310 mOsm/L), the myocardial contractility did not change; and when 4α-PDD was added to the hyperosmotic perfusate (390 mOsm/L), the inhibition of myocardial contractility by hyperosmia was increased by 27.1% (P<0.01). These results obtained indicate that TRPV4 is possibly involved in the osmotic pressure-induced inotropic effect.
Assuntos
Animais , Ratos , Coração , Fisiologia , Contração Miocárdica , Fisiologia , Pressão Osmótica , Ésteres de Forbol , Farmacologia , Ratos Sprague-Dawley , Canais de Cátion TRPV , FisiologiaRESUMO
We isolated mouse embryonic cardiomyocytes derived from timed-pregnant females at different periods and used patch-clamp technique to investigate the muscarinic cholinergic modulation of pacemaker current I(f) in different developmental stages. In early development stage (EDS), muscarinic agonist carbachol (CCh) significantly decreased the magnitude of the pacemaker current I(f) but had no effect in late development stage (LDS). Forskolin (a direct adenylate cyclase activator) and IBMX (a non-selective phosphodiesterase inhibitor) increased I(f) in both EDS and LDS cells. Interestingly, although both forskolin and IBMX increased basal I(f), their effects on CCh-inhibited I(f) were different. Forskolin did not reverse the inhibitory action of CCh until intermediate development stage (IDS). In contrast, IBMX reversed the inhibitory action of CCh on I(f) in EDS but not in IDS. It is suggested that a decrease in intracellular cAMP is a possible mechanism for CCh to modulate I(f). During the EDS and IDS CCh controls the cytoplasmic cAMP level by different pathways: In EDS, CCh modulates I(f) possibly by activating PDE which accelerates the breakdown of cAMP, but in IDS possibly by inhibiting adenylate cyclase (AC) which then reduces the synthesis of cAMP.
Assuntos
Animais , Feminino , Camundongos , Gravidez , Carbacol , Farmacologia , Colforsina , Metabolismo , Farmacologia , Coração , Embriologia , Fisiologia , Agonistas Muscarínicos , Farmacologia , Miócitos Cardíacos , Fisiologia , Marca-Passo Artificial , Inibidores de Fosfodiesterase , Metabolismo , Farmacologia , Receptores Muscarínicos , MetabolismoRESUMO
To explore the electrophysiological characteristics of embryonic cardiomyocytes, single embryonic cardiomyocytes were obtained from mice at different periods by a collegenase B digestion approach, whole cell patch clamp recording technique was used to record I(f) and I(Ca-L), and spontaneous action potential was also recorded. The morphological and spontaneous contractile properties of the isolated cells appeared to be typical embryonic cardiomyocytes when the cells were assessed by phase-contrast microscope. Whole cell recording of isolated cells is easily performed by the whole cell patch clamp technique. Elelctrophysiological properties of I(f) and I(Ca-L) from embryonic cardiomyocytes have been proved to be similar to those from adult pacemaker cells or cardiomyocytes. The established method of isolation is simple, stable, effective and reliable. It allows to obtain as early as 8.5-day embryonic myocytes. The electrophysiological recording of embryonic cardiomyocytes will provide a useful model for exploring the electrophysiological characteristics of embryonic cardiomyocytes and the possible mechanism underlying some heart diseases.
Assuntos
Animais , Camundongos , Potenciais de Ação , Fisiologia , Separação Celular , Métodos , Células Cultivadas , Eletrofisiologia , Embrião de Mamíferos , Miócitos Cardíacos , Biologia Celular , Fisiologia , Técnicas de Patch-ClampRESUMO
For determination the ionic mechanisms of the hypoxic acclimatization at the level of channels, male Spradue-Dawley rats were divided into two groups: control normoxic group and chronic intermittent hypoxic group [O2 concentration: (10 +/-0.5)%, hypoxia 8 h a day]. Using whole cell patch-clamp technique, voltage-gated potassium channel currents (IK(V)) were recorded in freshly isolated pulmonary arterial smooth muscle cells (PASMCs) of rat with acute isolated method. The effect of acute hypoxia on IK(V) of PASMCs from chronic intermittent hypoxia group was investigated to offer some basic data for clarifying the ionic mechanisms of the hypoxic acclimatization. The results showed: (1) In control normoxic group, after acute hypoxia free-Ca(2+) solution, the resting membrane potential (Em) of PASMCs was depolarized significantly from -47.2+/-2.6 mV to -26.7+/-1.2 mV, and the IK(V) of PASMCs was decreased significantly from 153.4+/-9.5 pA/pF to 70.1+/-0.6 pA/pF, the peak current percent inhibition was up to (57.6+/-3.3)% at +60 mV, and current-voltage relationship curve shifted to the right. (2) In chronic intermittent hypoxic group, the IK(V) of PASMCs was decreased significantly by exposure to intermittent hypoxia in a time-dependent manner, appeared to start on day 10 and continued to day 30 (the longest time tested) of hypoxia, and current-voltage relationship curve shifted to the right in a time-dependent manner. (3) Compared with the control normoxic group, the percent IK(V) inhibition by acute hypoxia was significantly attenuated in the chronic intermittent hypoxia group and this inhibition effect declined with time exposure to hypoxia. The results suggest that K(V) inhibition was significantly attenuated by chronic intermittent hypoxia, and this effect may be a critical mechanism of the body hypoxic acclimatization.
Assuntos
Animais , Masculino , Ratos , Separação Celular , Hipóxia , Músculo Liso Vascular , Biologia Celular , Metabolismo , Fisiologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Artéria Pulmonar , Metabolismo , Patologia , Ratos Sprague-DawleyRESUMO
This study was designed to investigate the effects of platelet activating factor (PAF) on the action potential and potassium currents in guinea-pig ventricular myocytes. Whole cell patch clamp techniques were used. With 5 mmol/L ATP in the pipette electrode(mimic normal condition), 1 micromol/L PAF increased APD(90) from 225.8+/-23.3 to 352.8+/-29.8 ms (n=5, P<0.05), decreased I(K1) and I(K) tail currents from -6.1+/-1.3 to -5.6+/-1.1 nA (n=5, P<0.05) at -120 mV and from 173.5+/-16.7 to 152.1+/-11.5 pA (P<0.05, n=4) at +30 mV, respectively. But PAF had no effect on I(K1) at potentials within the normal range of membrane potentials (between -90 mV and +20 mV). In the contrary, without ATP in the pipette electrode by which I(K.ATP) was activated (mimic ischemic condition), 1 micro mol/L PAF shortened APD(90) from 153+/-24.6 to 88.2+/-19.4 ms (n=5, P<0.01). Incubation of myocytes with 1 micro mol/L glibenclamide, a blocker of I(K.ATP ) could restore prolongation of APD induced by PAF. In conclusion, in guinea-pig ventricular myocytes, with 5 mmol/L ATP in the pipette PAF could prolong APD partly due to the inhibition of I(K); while with 0 mmol/L ATP in the pipette, PAF could induce an activation of I(K.ATP), hence a decrease in APD. It is suggested that PAF may amplify the heterogeneity between ischemic and normal cardiac myocytes during ischemia /reperfusion, which may play a vital role in the pathogenesis of the arrhythmias induced by ischemia /reperfusion.
Assuntos
Animais , Potenciais de Ação , Trifosfato de Adenosina , Farmacologia , Glibureto , Farmacologia , Cobaias , Ventrículos do Coração , Biologia Celular , Metabolismo , Miócitos Cardíacos , Metabolismo , Fisiologia , Técnicas de Patch-Clamp , Fator de Ativação de Plaquetas , Farmacologia , Canais de PotássioRESUMO
The effects of adrenomedullin (ADM) on the L-type calcium currents (I(Ca,L)) and the mechanism of the signal transduction process were studied. Enzymatically isolated guinea-pig ventricular myocytes were used to measure ICa,L with whole-cell patch-clamp techniques. ADM at the concentrations of 1-100 nmol/L decreased ICa,L in a dose-dependent manner (P<0.05). ADM22-52) (100 nmol/L), a specific ADM-receptor antagonist, completely abolished the ADM-induced inhibition of ICa,L. Pretreatment of the cells with H-89 (10 micromol/L), a specific PKA inhibitor, did not attenuate the effects of ADM. Intracellular application of 10 micromol/L PKC19-36), a specific PKC inhibitor, prevented the ADM-induced inhibition of the ICa,L, while the specific PKC activator PMA could mimic the effects of ADM on the ICa,L. PMA (1 micromol/L) decreased the ICa,L by 32.26+/-4.20%(P<0.05). These findings indicate that ADM can inhibit the ICa,L in guinea-pig ventricular myocytes, and the inhibition is mediated by the specific ADM-receptor and an activation of protein kinase C.