Selective and quasi-continuous switching of ferroelectric Chern insulator devices for neuromorphic computing.

Quantum materials exhibit dissipationless topological edge state transport with quantized Hall conductance, offering notable potential for fault-tolerant computing technologies. However, the development of topological edge state-based computing devices remains a challenge. Here we report the selective and quasi-continuous ferroelectric switching of topological Chern insulator devices, showcasing a proof-of-concept demonstration in noise-immune neuromorphic computing. We fabricate this ferroelectric Chern insulator device by encapsulating magic-angle twisted bilayer graphene with doubly aligned h-BN layers and observe the coexistence of the interfacial ferroelectricity and the topological Chern insulating states. The observed ferroelectricity exhibits an anisotropic dependence on the in-plane magnetic field. By tuning the amplitude of the gate voltage pulses, we achieve ferroelectric switching between any pair of Chern insulating states in the presence of a finite magnetic field, resulting in 1,280 ferroelectric states with distinguishable Hall resistance levels on a single device. Furthermore, we demonstrate deterministic switching between two arbitrary levels among the record-high number of ferroelectric states. This unique switching capability enables the implementation of a convolutional neural network resistant to external noise, utilizing the quantized Hall conductance levels of the Chern insulator device as weights. Our study provides a promising avenue towards the development of topological quantum neuromorphic computing, where functionality and performance can be drastically enhanced by topological quantum materials.

Original surgical technique for the treatment of patellofemoral instability after failure of conservative treatment.

INTRODUCTION: Acute patellar dislocation is a common but serious injury that can significantly impact a patient's functional prognosis. The objective of this retrospective study is to evaluate the clinical outcomes of arthroscopic medial patellofemoral ligament (MPFL) reconstruction and plication of the medial patellar retinaculum using suture anchors in adolescent patients with first-time acute patellar dislocation (APD) and MPFL insertion injury. HYPOTHESIS: Tightening repair of the medial retinaculum complex can result in favorable clinical and functional outcomes in this patient population. MATERIALS AND METHODS: A total of 84 adolescent patients with first-time APD and with an average age of 15.5 years (10-22) were included in the study. Of these patients, 61 (7 male and 54 female) underwent arthroscopic suture anchor plication for medial patellar retinaculum, while the other 23 were successfully treated non-operatively. Radiographic outcomes, including the congruence angle (CA), lateral patellofemoral angle (LPA), and patellar tilt angle (PTA), were evaluated preoperatively and at the last follow-up visit in the surgical group. Functional outcomes were assessed using the Lille Patello-Femoral Score, Lysholm Score, and Kujala Score at the same time points. In addition, the surgical and non-operative treatment success groups were compared in terms of both radiographic and functional outcomes. RESULTS: Mean follow-up was 40.9 months (24-60). Fifty-nine knees showed excellent or good results postoperatively, 2 patients had a recurrent patellar subluxation. The Lille Patello-Femoral Score was 96.9±4.7 at the last follow-up. The subjective Lysholm Score and Kujala Score improved significantly, from 58.6 to 91.9 and from 60.4 to 88.9, respectively. The radiographic CA, LPA and PTA improved significantly, from 19.8±2.1° to -6.7±1.7°, from -7.4±2.2° to 5.7±1.8° and from 23.8±2.9° to 12.3±2.3°, respectively. There was no statistically significant difference in functional and radiographic assessments between the success with non-operative treatment group and the surgery group. CONCLUSION: The results of this study suggest that arthroscopic MPFL insertion reconstruction and plication using suture anchors, which is less invasive and improves patella stability, can lead to favorable clinical and functional outcomes in adolescent patients with first-time acute patellar dislocation and insertion injury. This treatment approach should be considered as a viable option for this patient population. LEVEL OF EVIDENCE: IV; monocentric retrospective descriptive study.

[Bioinformatics analysis of the microRNA expression profile in the peripheral blood lymphocytes of Kazakh patients with essential hypertension in Xinjiang].

This study aimed to investigate the differential expression profiles of microRNAs (miRNAs) in peripheral blood lymphocytes between patients with essential hypertension and healthy individuals in Xinjiang Kazakh and to provide insight into the mechanism involved in the pathogenesis of hypertension in this ethnic group. From April 2016 to May 2019, 30 Kazakh patients with essential hypertension in the inpatient and outpatient departments of Cardiology, First Affiliated Hospital of Shihezi University were used as the hypertension group; 30 healthy Kazakh patients were used as the control group. The miRNA expression profiles in peripheral blood lymphocytes of 6 Kazakh hypertensive patients and 6 matched healthy individuals were compared, and the differentially expressed miRNAs were analyzed by cluster analysis, GSEA enrichment analysis, target gene prediction, target gene annotation and other bioinformatics analyses. In addition, qRT-PCR was used to verify the differentially expressed miRNAs. The results showed that compared with the control group, 73 differentially expressed miRNAs were identified in the hypertension group, of which 39 miRNAs were up-regulated and 34 miRNAs were down-regulated. A total of 11 miRNAs related to hypertension were screened by GSEA enrichment analysis, including hsa-miR-100-5p, hsa-miR-150-5p, hsa-miR-299-5p, hsa-miR-299-3p, hsa-miR-296-5p, hsa-miR-196b-5p, hsa-miR-503-5p, hsa-miR-628-5p, hsa-miR-874-3p, hsa-miR-543 and hsa-miR-940. qRT-PCR test found that the expression of hsa-miR-100-5p, hsa-miR-299-5p, hsa-miR-299-3p, hsa-miR-196b-5p, hsa-miR-503-5p, hsa-miR-628-5p and hsa-miR-543 was up-regulated, while the expression of hsa-miR-150-5p, hsa-miR-296-5p, hsa-miR-874-3p and hsa-miR-940 was down-regulated in the hypertension group compared with the control group. The expression trend in the gene chip was consistent with the results verified by qRT-PCR. Using online database to predict target genes of 11 miRNAs related to hypertension, we found that a total of 1 647 target genes might be regulated by these 11 miRNAs. GO function enrichment showed that (a) in biological processes, the predicted hypertension related target genes are mainly relevant to nervous system development, cellular localization, regulation of cellular metabolic process, generation of neurons and positive regulation of biological process; (b) In terms of cellular components, they are mainly related to membrane-bounded organelle, cytoplasm, intracellular membrane-bounded organelle, synapse part, neuron part, and nucleoplasm; (c) In terms of molecular function, they are mainly related to protein binding, transcription regulatory region DNA binding, RNA polymerase II regulatory region DNA binding, transcription regulator activity, and ion binding. KEGG enrichment analysis showed that the p53 signaling pathway, adrenergic signaling in cardiomyocytes, cAMP signaling pathway, TGF-ß signaling pathway, endocrine and other factor-regulated calcium reabsorption, mTOR signaling pathway, and aldosterone-regulated sodium reabsorption may be related to the occurrence and development of hypertension. In conclusion, there are significant differences in the expression of miRNAs in peripheral blood lymphocytes between Kazakh patients with essential hypertension and healthy people. The differentially expressed miRNAs may be related to the occurrence and development of essential hypertension in Kazakh. However, the underlying mechanism needs to be further explored and verified.

Liver X receptors conserve the therapeutic target potential for the treatment of rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic multi-system autoimmune disease with extremely complex pathogenesis. Significantly altered lipid paradox related to the inflammatory burden is reported in RA patients, inducing 50% higher cardiovascular risks. Recent studies have also demonstrated that lipid metabolism can regulate many functions of immune cells in which metabolic pathways have altered. The nuclear liver X receptors (LXRs), including LXRα and LXRß, play a central role in regulating lipid homeostasis and inflammatory responses. Undoubtedly, LXRs have been considered as an attractive therapeutic target for the treatment of RA. However, there are some contradictory effects of LXRs agonists observed in previous animal studies where both pro-inflammatory role and anti-inflammatory role were revealed for LXRs activation in RA. Therefore, in addition to updating the knowledge of LXRs as the prominent regulators of lipid homeostasis, the purpose of this review is to summarize the effects of LXRs agonists in RA-associated immune cells, to explore the underlying reasons for the contradictory therapeutic effects of LXRs agonists observed in RA animal models, and to discuss future strategy for the treatment of RA with LXRs modulators.

Carbenoxolone decreases monocrotaline­induced pulmonary inflammation and pulmonary arteriolar remodeling in rats by decreasing the expression of connexins in T lymphocytes.

The adaptive immune response mediated by T lymphocytes is a well­established factor in the pathogenesis of pulmonary inflammation. Changes in the expression of various connexins (Cxs) or disruption of connexin­mediated cellular communication in T lymphocytes contribute to inflammation or tissue remodeling. The aim of the present study was to investigate the potential therapeutic value of blocking Cxs in a monocrotaline (MCT)­induced pulmonary inflammation rat model. Carbenoxolone (CBX) was used to inhibit connexin­mediated cellular communication. An MCT rat model was established by intraperitoneal (i.p.) injection of a single dose of MCT (60 mg/kg), and CBX treatment (20 µg/kg/day, i.p.) was initiated on the day following MCT treatment for 28 days. Vehicle­treated male Sprague­Dawley rats were used as the negative control. The MCT rat model was evaluated by measuring the pulmonary artery flow acceleration time and right ventricular hypertrophy index (RVHI). Histopathological features of the lung tissues and pulmonary arteriolar remodeling were assessed. The proportions of T lymphocyte subtypes, Cx40/cx43 expression in the T cell subtypes and the cytokine levels in the plasma and the lung tissues were also analyzed. Pharmacological inhibition of Cxs using CBX attenuated MCT­induced right ventricular hypertrophy, pulmonary arteriolar remodeling, lung fibrosis and inflammatory cell infiltration by decreasing the RVHI, pulmonary arterial wall thickening, collagen deposition and pro­inflammatory cytokines production as well as CD3+ and CD4+ T cell accumulation in lung tissues of MCT­treated rats. Furthermore, flow cytometry analysis revealed that CBX may inhibit MCT­induced Cx40 and Cx43 expression in CD4+ and CD8+ T lymphocytes in lung tissues. The present study provides evidence that pharmacological inhibition of Cxs may attenuate MCT­induced pulmonary arteriolar remodeling and pulmonary inflammatory response, at least in part, by decreasing Cx expression. The results highlight the critical role of Cxs in T lymphocytes in the MCT­induced pulmonary inflammatory response and that targeting of Cxs may be a potential therapeutic method for treating pulmonary inflammatory diseases.

ß­estradiol alleviates hypertension­ and concanavalin A­mediated inflammatory responses via modulation of connexins in peripheral blood lymphocytes.

Gap junctions (GJs) formed by connexins (Cxs) in T lymphocytes have been reported to have important roles in the T lymphocyte­driven inflammatory response and hypertension­mediated inflammation. Estrogen has a protective effect on cardiovascular diseases, including hypertension and it attenuates excessive inflammatory responses in certain autoimmune diseases. However, the mechanisms involved in regulating the pro­inflammatory response are complex and poorly understood. The current study investigated whether ß­estradiol suppresses hypertension and pro­inflammatory stimuli­mediated inflammatory responses by regulating Cxs and Cx­mediated GJs in peripheral blood lymphocytes. Male, 16­week­old spontaneously hypertensive rats (SHR) and Wistar­Kyoto rats (WKY) rats were randomly divided into the following three groups: WKY rats, vehicle (saline)­treated SHRs, and ß­estradiol (20 µg/kg/day)­treated SHRs. ß­estradiol was administered subcutaneously for 5 weeks. Hematoxylin and eosin staining was performed to evaluate target organ injury. Flow cytometry and ELISA were used to measure the populations of T lymphocyte subtypes in the peripheral blood, and expression of Cx40/Cx43 in T cell subtypes, and pro­inflammation cytokines levels, respectively. ELISA, a dye transfer technique, immunofluorescence and immunoblotting were used to analyze the effect of ß­estradiol on pro­inflammatory cytokine secretion, Cx­mediated GJs and the expression of Cxs in concanavalin A (Con A)­stimulated peripheral blood lymphocytes isolated from WKY rat. ß­estradiol significantly decreased blood pressure and inhibited hypertension­induced target organ injury in SHRs. Additionally, ß­estradiol treatment significantly improved the immune homeostasis of SHRs, as demonstrated by the decreased percentage of cluster of differentiation (CD)4+/CD8+ T­cell subset ratio, reduced serum levels of pro­inflammatory cytokines and increased the percentage of CD4+CD25+ T cells. ß­estradiol also markedly reduced the expression of Cx40/Cx43 in T lymphocytes from SHRs. In vitro, ß­estradiol significantly suppressed the production of pro­inflammatory cytokines, reduced communication via Cx­mediated gap junctions and decreased the expression of Cx40/Cx43 in Con A­stimulated lymphocytes. These results indicate that ß­estradiol attenuates inflammation and end organ damage in hypertension, which may be partially mediated via downregulated expression of Cxs and reduced function of Cx­mediated GJ.

Increased expression and functionality of the gap junction in peripheral blood lymphocytes is associated with hypertension-mediated inflammation in spontaneously hypertensive rats.

BACKGROUND: Imbalances in circulating T lymphocytes play critical roles in the pathogenesis of hypertension-mediated inflammation. Connexins (Cxs) in immune cells are involved in the maintenance of homeostasis of T lymphocytes. However, the association between Cxs in peripheral blood T lymphocytes and hypertension-mediated inflammation remains unknown. This study was designed to investigate the role of Cxs in T lymphocytes in hypertension-mediated inflammation in spontaneously hypertensive rats (SHRs). METHODS: The systolic blood pressure (SBP) in Wistar-Kyoto (WKY) rats and SHRs was monitored using the tail-cuff method. The serum cytokine level was determined using ELISA. The proportions of different T-lymphocyte subtypes in the peripheral blood, the expressions of Cx40/Cx43 in the T-cell subtypes, and the gap junctional intracellular communication (GJIC) of peripheral blood lymphocytes were measured using flow cytometry (FC). The accumulations of Cx40/Cx43 at the plasma membrane and/or in the cytoplasm were determined using immunofluorescence staining. The in vitro mRNA levels of cytokines and GJIC in the peripheral blood lymphocytes were respectively examined using real-time PCR and FC after treatment with Gap27 and/or concanavalin A (Con A). RESULTS: The percentage of CD4+ T cells and the CD4+/CD8+ ratio were high, and the accumulation or expressions of Cx40/Cx43 in the peripheral blood lymphocytes in SHRs were higher than in those of WKY rats. The percentage of CD8+ and CD4+CD25+ T cells was lower in SHRs. The serum levels of IL-2, IL-4 and IL-6 from SHRs were higher than those from WKY rats, and the serum levels of IL-2 and IL-6 positively correlated with the expression of Cx40/Cx43 in the peripheral blood T lymphocytes from SHRs. The peripheral blood lymphocytes of SHRs exhibited enhanced GJIC. Cx43-based channel inhibition, which was mediated by Gap27, remarkably reduced GJIC in lymphocytes, and suppressed IL-2 and IL-6 mRNA expressions in Con A stimulated peripheral blood lymphocytes. CONCLUSIONS: Our data suggest that Cxs may be involved in the regulation of T-lymphocyte homeostasis and the production of cytokines. A clear association was found between alterations in Cxs expression or in Cx43-based GJIC and hypertension-mediated inflammation.

Hydrogen Sulfide Attenuates Hypertensive Inflammation via Regulating Connexin Expression in Spontaneously Hypertensive Rats.

BACKGROUND Hydrogen sulfide (H2S) has anti-inflammatory and anti-hypertensive effects, and connexins (Cxs) are involved in regulation of immune homeostasis. In this study, we explored whether exogenous H2S prevents hypertensive inflammation by regulating Cxs expression of T lymphocytes in spontaneously hypertensive rats (SHR). MATERIAL AND METHODS We treated SHR with sodium hydrosulfide (NaHS) for 9 weeks. Vehicle-treated Wistar-Kyoto rats (WKYs) were used as a control. The arterial pressure was monitored by the tail-cuff method, and vascular function in basilar arteries was examined by pressure myography. Hematoxylin and eosin staining was used to show vascular remodeling and renal injury. The percentage of T cell subtypes in peripheral blood, surface expressions of Cx40/Cx43 on T cell subtypes, and serum cytokines level were determined by flow cytometry or ELISA. Expression of Cx40/Cx43 proteins in peripheral blood lymphocytes was analyzed by Western blot. RESULTS Chronic NaHS treatment significantly attenuated blood pressure elevation, and inhibited inflammation of target organs, vascular remodeling, and renal injury in SHR. Exogenous NaHS also improved vascular function by attenuating KCl-stimulated vasoconstrictor response in basilar arteries of SHR. In addition, chronic NaHS administration significantly suppressed inflammation of peripheral blood in SHR, as evidenced by the decreased serum levels of IL-2, IL-6, and CD4/CD8 ratio and the increased IL-10 level and percentage of regulatory T cells. NaHS treatment decreased hypertension-induced Cx40/Cx43 expressions in T lymphocytes from SHR. CONCLUSIONS Our data demonstrate that H2S reduces hypertensive inflammation, at least partly due to regulation of T cell subsets balance by Cx40/Cx43 expressions inhibition.

Connexin 43 in splenic lymphocytes is involved in the regulation of CD4+CD25+ T lymphocyte proliferation and cytokine production in hypertensive inflammation.

Chronic inflammation promotes the development of hypertension and is associated with increased T cell infiltration and cytokine production in impaired organs. Gap junction protein connexin 43 (Cx43), is ubiquitously expressed in immune cells and plays an important role in T cell proliferation and activation, and cytokine production. However, the correlation between Cx43 in T cells and the hypertensive inflammatory response remains unknown. Thus, in this study, we wished to examine this correlation. First, our results revealed that hypertension caused significant thickening of the vascular wall, inflammatory cell infiltration into part of the renal interstitium and glomerular atrophy, and it increased the tubular damage scores in the kidneys of spontaneously hypertensive rats (SHRs). Moreover, the SHRs exhibited stenosis in the central artery wall ofthe spleen with increased serum levels of interleukin (IL)-2 and IL-6 compared with normotensive Wistar-Kyoto (WKY) rats. The spleens of the SHRs exhibited a significantly decreased percentage of CD4+CD25+ (Treg) T cells. However, the percentages of CD3+, CD4+ and CD8+ T cell and the levels of CD4+Cx43 and CD8+Cx43 did not differ significantly between the SHRs and WKY rats. In cultured lymphocytes from the SHRs and WKY rats, low percentages of Treg cells and reduced cytokine (IL-2 and IL-6) mRNA expression levels were observed in the lymphocytes obtained from the SHRs and WKY rats treated with the connexin blocker, Gap27, or concanavalin A (ConA) plus Gap27. The effects of ConA and Gap27 differed between the SHRs and WKY rats. On the whole, our findings demonstrate that the splenic Treg cell-mediated suppression in SHRs may be involved in hypertensive inflammatory responses. Cx43 in the gap junctional channel may regulate lymphocyte activation and inflammatory cytokine production.

Up-regulation of gap junction in peripheral blood T lymphocytes contributes to the inflammatory response in essential hypertension.

Inflammation has been shown to play an important role in the mechanisms involved in the pathogenesis of hypertension. Connexins (Cxs)-based gap junction channels (GJCs) or hemichannels (HCs) are involved in the maintenance of homeostasis in the immune system. However, the role of Cx43-based channels in T-lymphocytes in mediating the immune response in essential hypertension is not fully understand. The present study was designed to investigate the role of Cxs-based channels in T lymphocytes in the regulation of hypertension-mediated inflammation. The surface expressions of T lymphocyte subtypes, Cx40/Cx43, and inflammatory cytokines (IFN-γ (interferon-gamma) and TNF-ɑ (tumor necrosis factor alpha)) in T cells, as well as gap junction communication of peripheral blood lymphocytes from essential hypertensive patients (EHs) and normotensive healthy subjects (NTs) were detected by flow cytometry. Expression levels and phosphorylation of Cx43 protein in peripheral blood lymphocytes of EHs and NTs were analyzed by Western blot. The proliferation rate of peripheral blood mononuclear cells (PBMCs) after treatment with a Cxs inhibitor was examined by a CCK-8 assay. The levels of inflammatory cytokines were detected using ELISA. Within the CD3+ T cell subsets, we found a significant trend toward an increase in the percentage of CD4+ T cells and CD4+/CD8+ ratio as well as in serum levels of IFN-γ and TNF-ɑ in the peripheral blood of EHs compared with those in NTs. Moreover, the peripheral blood lymphocytes of EH patients exhibited enhanced GJCs formation, increased Cx43 protein level and Cx43 phosphorylation at Ser368, and a significant increase in Cx40/Cx43 surface expressions levels in CD4+ or CD8+ T lymphocytes. Cx43-based channel inhibition by a mimetic peptide greatly reduced the exchange of dye between lymphocytes, proliferation of stimulated lymphocytes and the pro-inflammatory cytokine levels of EHs and NTs. Our data suggest that Cx40/Cx43-based channels in lymphocytes may be involved in the regulation of T lymphocyte proliferation and the production of pro-inflammatory cytokines, which contribute to the hypertensive inflammatory response.

Enhanced gap junctional channel activity between vascular smooth muscle cells in cerebral artery of spontaneously hypertensive rats.

The aim of the present study is to investigate the effects of hypertension on the gap junctions between vascular smooth muscle cells (VSMCs) in the cerebral arteries (CAs) of spontaneously hypertensive rats (SHRs). The functions of gap junctions in the CAs of VSMCs in SHRs and control normotensive Wistar-Kyoto (WKY) rats were studied using whole-cell patch clamp recordings and pressure myography, and the expression levels of connexins were analyzed using reverse transcription-quantitative polymerase chain reaction and Western blot analyses. Whole-cell patch clamp measurements revealed that the membrane capacitance and conductance of in situ VSMCs in the CAs were significantly greater in SHRs than in WKY rats, suggesting that gap junction coupling is enhanced between VSMCs in the CAs of SHRs. Application of the endothelium-independent vasoconstrictors KCl or phenylephrine (PE) stimulated a greater vasoconstriction in the CAs of SHRs than in those of WKY rats. The EC50 value of KCl was 24.9 mM (n = 14) and 36.9 mM (n=12) for SHRs and WKY rats, respectively. The EC50 value of PE was 0.9 µM (n = 7) and 2.2 µM (n = 7) for SHRs and WKY rats, respectively. Gap junction inhibitors 18ß-glycyrrhetinic acid (18ß-GA), niflumic acid (NFA), and 2-aminoethoxydiphenyl borate (2-APB) attenuated KCl-induced vasoconstriction in SHRs and WKY rats. The mRNA and protein expression levels of the gap junction protein connexin 45 (Cx45) were significantly higher in the CAs of SHRs than in those of WKY rats. Phosphorylated Cx43 protein expression was significantly higher in the CAs of SHRs than in those of WKY rats, despite the total Cx43 mRNA and protein expression levels in the cerebral artery (CA) exhibiting no significant difference between SHRs and WKY rats. Increases in the expression of Cx45 and phosphorylation of Cx43 may promote gap junction communication among VSMCs in the CAs of SHRs, which may enhance the contractile response of the CA to vasoconstrictors.

Role of gap junctions in the contractile response to agonists in the mesenteric resistance artery of rats with acute hypoxia.

Hypoxic exposure results in the vascular dysfunction and reduction of vasomotor responses and thus disrupts or reduces blood flow in the resistance arteries. Connexin (Cx)-mediated gap junctional intercellular communication (GJIC) serves a critical role in the regulation of vasomotor tone and the synchronized contraction of arteries, however whether the adverse effect of hypoxia on vasomotor responses in vascular smooth muscle layer of resistance arteries is involved in changes in the GJIC and the expression of Cx43 and Cx45 remains to be elucidated. Pressure myography, whole-cell patch clamp and western blot analysis were used to investigate the differences in expression and function of gap junction (GJ) in the vascular smooth muscle cells (VSMCs) of the mesenteric resistance artery (MRA) from Sprague­Dawley (SD) rats in normoxia and acute hypoxia groups. In the present study, whole­cell patch clamp measurements demonstrated a significant reduction in the membrane capacitance and conductance in the VSMCs of the MRAs in the acute hypoxia (5 min) group (n=13) compared with the normoxia group (n=13), which suggested that exposure to acute hypoxia of 5 min decreased the coupling of the GJ between the VSMCs of MRAs in SD rats. Pressure myographic analysis demonstrated that 0.1­100 µM phenylephrine (PE)­induced MRA vasoconstriction was less sensitive under the acute hypoxic condition (n=7) compared with the normoxia condition (n=9) following treatment with 100 µM 2­aminoethoxydiphenyl borate for 20 min. Compared with SD rats under normoxia, the PE­initiated vasoconstrictive frequency and amplitude under acute hypoxia for 20, 40 and 60 min in the MRAs of SD rats was markedly attenuated (n=7). The results of western blot analysis indicated that the expression levels of Cx43 and Cx45 in MRA under acute hypoxia (1 h) were lower compared with normoxia. Cx43­and Cx45­mediated GJs serve a significant role in the regulation of the vasomotor function of MRA during hypoxia and may be essential for the adjustment of vasomotor tone in response to acute hypoxia.

[Effect of Gualou Xiebai Banxia decoction combined with Xuefu Zhuyu decoction on myocardial apoptosis and relevant protein expressions in miniature swine phlegm and blood stasis type coronary heart disease model].

There have been very few studies on the effect of Gualou Xiebai Banxia decoction combined with Xuefu Zhuyu decoction in inhibiting apoptosis in myocardial ischemial injury caused by coronary heart disease. In this experiment, Gualou Xiebai Banxia decoction combined with-Xuefu Zhuyu decoction were used to intervene the miniature swine phlegm and blood stasis type coronary heart disease model, in order to observe the effect of the combined prescription on the myocardial apoptosis and the expressions of Bcl-2, Bax, Caspase-3, Caspase-9 in the model. Totally 15 Chinese experimental miniature swine were adopted and randomly divided into the control group, the model group and the phlegm and stasis-treating group. The model group and the stasis-treating group were fed with high fat diets for two weeks, intervened with the coronary artery injury and then given drugs and high fat diets for eight weeks. The control group was fed with ordinary diets for 10 weeks, without the coronary artery injury. After the experiment, myocardia at the juncture of infracted areas were collected and made into formalin-fixed paraffin sections. The TDT-mediate dUTP nick end labeling (TUNEL) assay was used to detect the myocardial apoptosis. The immunohistochemistry (IHC) technique was applied to detect Bcl-2, Bax, Caspase-3, Caspase-9 levels in myocardial tissues. According to the findings, the apoptosis indexes (AI) for the control group, the model group and the phlegm and stasis-treating group were 0.92%, 27.68%, 17.28%, respectively. The AI of the phlegm and stasis-treating group was significantly lower than that of the model group (P < 0.01). Compared with the model group, the phlegm and stasis-treating group showed significantly higher Bcl-2 protein expression (P < 0.01) and lower Bax, Caspase-3 and Caspase-9 protein expressions (P < 0.01). In conclusion, Gualou Xiebai Banxia decoction combined with Xuefu Zhuyu decoction have a significant protective effect against the myocardial apoptosis in miniature swine phlegm and blood stasis type coronary heart disease model.

The enhancement of Cx45 expression and function in renal interlobar artery of spontaneously hypertensive rats at different age.

BACKGROUND/AIMS: This study was designed to investigate the expression and function of gap junction protein connexin 45 (Cx45) in renal interlobar artery (RIA) of spontaneously hypertensive rats (SHR), and the association between hypertension and enhanced vasoconstrictive response in SHR. METHODS: Western blot analysis and pressure myography were used to examine the differences in expression and function of Cx45 in vascular smooth muscle cells (VSMCs) of RIA between SHR and normotensive Wistar-Kyoto (WKY) rats. RESULTS: Our results demonstrated that 1) whole-cell patch clamp measurements showed that the membrane capacitance and conductance of in-situ RIA VSMCs of SHR were significantly greater than those of WKY rats (p<0.05, n=6), suggesting that the coupling of gap junction between VSMCs of RIA was enhanced in SHR; 2) the KCl or phenylephrine (PE)-stimulated RIA constriction was more pronounced in SHR than that in WKY rats (p<0.05, n=10). After applying a gap junction inhibitor 18ß-glycyrrhetintic acid (18ß-GA), the inhibitory effect of 18ß-GA on KCl or PE-induced vasoconstriction was greater in SHR (p<0.05, n=10); and 3) the expression of Cx45 in RIA of SHR was greater than that in WKY rats (p<0.05, n=3) at 4, 12 and 48 wks of age. CONCLUSIONS: The hypertension-induced elevation of Cx45 may affect communication between VSMCs and coupling between VSMCs and endothelium, which results in an increased vasoconstrictive response in renal artery and might contribute to the development of hypertension.

Human cytomegalovirus infection is associated with essential hypertension in Kazakh and Han Chinese populations.

BACKGROUND: We aimed to study the association between cytomegalovirus (CMV) infection and hypertension in Kazakh and Han populations from Xinjiang Province, China. MATERIAL/METHODS: We analyzed data on 800 Kazakhs (467 hypertension patients and 333 healthy control participants) and 800 Hans (482 hypertension patients and 318 healthy control participants) aged 18-84 years old. ELISA and real-time quantitative PCR coupled with restriction fragment length polymorphism analysis were applied for determining CMV infection and glycoprotein B (gB) genotypes, respectively. RESULTS: Serologic evidence of CMV infection was obtained for 95.4% and 90.1% of the Kazakhs and Hans, respectively. The CMV seroprevalence rates among the Kazakh and Han participants with hypertension were 96.8% and 89.8%, respectively. Multiple logistic regression analyses revealed statistically significant independent associations between CMV seropositivity and hypertension in Kazakh males and between CMV antibody titers and hypertension in Hans; significant relationships also existed between CMV antibody titers and blood pressure in Hans. In Kazakhs, 3 CMV gB genotypes were identified: gB2 and genotype mixtures gB1+gB2 and gB2+gB3. In Hans, 4 CMV gB genotypes were identified: gB1, gB2, gB1+gB2, and gB2+gB3. Of the 4 studied genotypes, gB2+gB3 showed a significant independent association with hypertension in Kazakh females. CONCLUSIONS: CMV infection is associated with essential hypertension in Kazakh males and Hans in Xinjiang. CMV seropositivity is associated with hypertension in Kazakh males, and CMV antibody titers are associated with blood pressure and hypertension in Han males and females. Moreover, the CMV gB2+gB3 genotype mixture is associated independently with essential hypertension in Kazakh females.

Differential effect of calcium-activated potassium and chloride channels on rat basilar artery vasomotion.

Spontaneous, rhythmical contractions, or vasomotion, can be recorded from cerebral vessels under both normal physiological and pathophysiological conditions. We investigated the cellular mechanisms underlying vasomotion in the cerebral basilar artery (BA) of Wistar rats. Pressure myograph video microscopy was used to study the changes in cerebral artery vessel diameter. The main results of this study were as follows: (1) The diameters of BA and middle cerebral artery (MCA) were 314.5±15.7 µm (n=15) and 233.3±10.1 µm (n=12) at 10 mmHg working pressure (P<0.05), respectively. Pressure-induced vasomotion occurred in BA (22/28, 78.6%), but not in MCA (4/31, 12.9%) from 0 to 70 mmHg working pressure. As is typical for vasomotion, the contractile phase of the response was more rapid than the relaxation phase; (2) The frequency of vasomotion response and the diameter were gradually increased in BA from 0 to 70 mmHg working pressure. The amplitude of the rhythmic contractions was relatively constant once stable conditions were achieved. The frequency of contractions was variable and the highest value was 16.7±4.7 (n=13) per 10 min at 60 mmHg working pressure; (3) The pressure-induced vasomotion of the isolated BA was attenuated by nifedipine, NFA, 18ß-GA, TEA or in Ca(2+)-free medium. Nifedipine, NFA, 18ß-GA or Ca(2+)-free medium not only dampened vasomotion, but also kept BA in relaxation state. In contrasts, TEA kept BA in contraction state. These results suggest that the pressure-induced vasomotion of the isolated BA results from an interaction between Ca(2+)-activated Cl(-) channels (CaCCs) currents and K(Ca) currents. We hypothesize that vasomotion of BA depends on the depolarizing of the vascular smooth muscle cells (VSMCs) to activate CaCCs. Depolarization in turn activates voltage-dependent Ca(2+) channels, synchronizing contractions of adjacent cells through influx of extracellular calcium and the flow of calcium through gap junctions. Subsequent calcium-induced calcium release from ryanodine-sensitive stores activates K(Ca) channels and hyperpolarizes VSMCs, which provides a negative feedback loop for regenerating the contractile cycle.

Role of gap junctions in the contractile response to agonists in the mesenteric artery of spontaneously hypertensive rats.

To investigate the effects of hypertension on the changes in gap junctions between vascular smooth muscle cells (VSMCs) in the mesenteric artery (MA) of spontaneously hypertensive rats (SHRs). Whole-cell patch clamp, pressure myography, real-time quantitative reverse transcription PCR (qRT-PCR), western blot analysis and transmission electron microscopy were used to examine the differences in expression and function of the gap junction between MA VSMCs of SHR and control normotensive Wistar-Kyoto (WKY) rats. (1) Whole-cell patch clamp measurements showed that the membrane capacitance and conductance of in-situ MA VSMCs of SHR were significantly greater than those of WKY rats (P<0.05), suggesting enhanced gap junction coupling between MA VSMCs of SHR. (2) The administration of phenylephrine (PE) and KCl (an endothelium-independent vasoconstrictor) initiated more pronounced vasoconstriction in SHR versus WKY rats (P<0.05). Furthermore, 2-APB (a gap junction inhibitor) attenuated PE- and KCl-induced vasoconstriction, and the inhibitory effects of 2-APB were significantly greater in SHR (P<0.05). (3) The expression of connexin 45 (Cx45) mRNA and protein in the MA was greater in SHR versus WKY rats (P<0.05). The level of phosphorylated Cx43 was significantly higher in SHR versus WKY rats (P<0.05), although the expression of total Cx43 mRNA and protein in the MA was equivalent between SHR and WKY rats. Electron microscopy revealed that the gap junctions were significantly larger in SHR versus WKY rats. Increases in the expression of Cx45 and phosphorylation of Cx43 may contribute to the enhancement of communication across gap junctions between MA VSMCs of SHR, which may increase the contractile response to agonists.

Long-term effect of stent coating with zedoary essential components on neointimal formation in the porcine coronary artery.

OBJECTIVE: To examine the effect of the zedoary essential component-eluting stent (ZES) on a porcine coronary neointimal formation. METHODS: ZES, sirolimus-eluting stents (SES), and bare metal stents (BMS) were randomly implanted in three different major epicardial vessels in 36 balloon-injured pigs. Coronary angiography, optical coherence tomography, and histomorphological analysis were used to determine antihyperplasia effects. RESULTS: ZES and SES had a significantly larger lumen diameter and area, and reduced diameter and area of stenosis in arteries at 30 and 90 days compared with arteries implanted with BMS (P<0.01). Histomorphometric analysis showed moderate inflammatory responses, such as infiltration of mononuclear cells, lymphocytes, and multinucleated giant cells in some arteries with SES compared with ZES (P<0.05). Injury scores were not different among the three groups at 30 and 90 days. The endothelialization score in the SES group was 2.69 ± 0.42 at 30 days and 2.83 ± 0.39 at 90 days compared with the ZES and BMS groups (both were 3.00 ± 0.00 at either 30 or 90 days, P<0.05). Well developed endothelium was observed in the ZES group, while incomplete endothelium and inflammatory cells were observed with stent struts partly naked at the vessel lumen in the SES group. CONCLUSION: The ZES inhibits neointimal hyperplasia with good endothelia coverage in the porcine balloon injury coronary model.

[Comparison of membrane current of vascular smooth muscle cells in brain artery of spontaneously hypertensive rats and Wistar rats].

OBJECTIVE: To investigate the difference in membrane current of vascular smooth muscle cells (VSMCs) in brain artery (BA) of spontaneously hypertensive rats (SHR) and Wistar rats. METHODS: We compared the properties of spontaneous transient outward K+ currents (STOCs), the density and composition of current of VSMCs in BA of SHR and Wistar rats by whole-cell patch clamp technique. RESULTS: (1) When the command voltage was 0, + 20, + 40 and + 60 mV respectively, the current densities of VSMCs in BA of SHR and Wistar rats were significant different (P < 0.01). (2) The whole-cell current of VSMCs was partly inhibited by 1 mmol/L4-AP (voltage-gated K+ channel blocker) or 1 mmol/L TEA (big conductance Ca(2+)-activated K+ channel blocker) respectively. (3) The frequency and amplitude of STOCs in SHR were faster and bigger than those in Wistar rats. 1 mmol/L TEA almostly inhibited the STOCs, but not by 4-AP. CONCLUSION: These results suggest that the current densities of VSMCs in BA of SHR and Wistar rats are significant different, the outward current of VSMCs in BA of SHR and Wistar rats are composed by Kv and BK(Ca). SHR express more STOCs mediated by BK(Ca), than Wistar rats.

Fenamates block gap junction coupling and potentiate BKCa channels in guinea pig arteriolar cells.

We determined the actions of the fenamates, flufenamic acid (FFA) and niflumic acid (NFA), on gap junction-mediated intercellular coupling between vascular smooth muscle cells (VSMC) in situ of acutely isolated arteriole segments from the three vascular beds: the spiral modiolar artery (SMA), anterior inferior cerebellar artery (AICA) and mesenteric artery (MA), and on non-junctional membrane channels in dispersed VSMCs. Conventional whole-cell recording methods were used. FFA reversibly suppressed the input conductance (Ginput) or increased the input resistance (Rinput) in a concentration dependent manner, with slightly different IC50s for the SMA, AICA and MA segments (26, 33 and 56 µM respectively, P>0.05). Complete electrical isolation of the recorded VSMC was normally reached at ≥ 300 µM. NFA had a similar effect on gap junction among VSMCs with an IC50 of 40, 48 and 62 µM in SMA, AICA and MA segments, respectively. In dispersed VSMCs, FFA and NFA increased outward rectifier K(+)-current mediated by the big conductance calcium-activated potassium channel (BKCa) in a concentration-dependent manner, with a similar EC50 of ∼300 µM for both FFA and NFA in the three vessels. Iberiotoxin, a selective blocker of the BKCa, suppressed the enhancement of the BKCa by FFA and NFA. The KV blocker 4-AP had no effect on the fenamates-induced K(+)-current enhancement. We conclude that FFA and NFA blocked the vascular gap junction mediated electrical couplings uniformly in arterioles of the three vascular beds, and complete electrical isolation of the recorded VSMC is obtained at ≧300µM; FFA and NFA also activate BKCa channels in the arteriolar smooth muscle cells in addition to their known inhibitory effects on chloride channels.