[Comparison of clinical efficacy between closed reduction combined with semi-circular external fixator and minimally invasive percutaneous plate osteosynthesis (MIPPO) in the treatment of middle and distal tibia fractures].

OBJECTIVE: To compare the clinical efficacy between closed reduction combined with semi-circular external fixator and minimally invasive percutaneous plate osteosynthesis (MIPPO) in the treatment of middle anddistal tibia fractures. METHODS: The clinical data of sixty patients with middle and distal tibia fractures admitted between January 2019 and November 2022, were retrospectively analyzed. These patients were categorized into external fixation group (n=30) and internal fixation group (n=30). There were 18 males and 12 females in the external fixation group, with an average age of (49.29±2.35) years old. Among them, 14 patients presented with fractures on the left side, and 16 patients presented with fractures on the right side. Closed reduction, arched wire, and semi-circular external fixator were used for treatment. There were 20 males and 10 females in the internal fixation group, with an average age of (48.96±1.87) years old. Among them, 15 patients presented with fractures on the left side, and 15 patients presented with fractures on the right side. MIPPO technique was used for the treatment. Perioperative parameters, including time injury to surgery, surgical duration, incision length, intraoperative bleeding, time to active activity, and incision healing level, were compared between the two groups. Clinical outcomes were also assessed, including Johner-Wruhs scores, time to minimum pain-adapted full weight-bearing, visual analog scale (VAS), SF-36 scale, and complications. RESULTS: The external fixation group exhibited a significantly shorter incision length (1.36±0.86) cm and lower intraoperative bleeding (10.83±5.73) ml compared to the internal fixation group (12.74±3.12) cm and (86.47±8.90) ml, respectively(P<0.05). The postoperative active activity time (1.50±0.54) days and minimum pain-adapted full weight-bearing activity time(108.87±3.43) days in the external fixation group were slightly delayed than the internal fixation group(1.15±0.98) days and (105.27±3.68) days, respectively(P<0.05). Over a mean postoperative follow-up duration of (6.23±1.89) months, both groups showed improved VAS and SF-36 scale scores. There were no statistically significant differences in VAS and SF-36 scale scores 1, 3, 6 months post-operatively between the two groups(P>0.05). The intraoperative surgical time in the external fixation group (35.42±9.31) minutes was shorter than that in the internal fixation group(74.22±7.81) minutes (P<0.05). There was no intraoperative vascular or nerve injury, nor postoperative skin necrosis in the external fixation group. However, skin necrosis was observed in 6 patientsin the internal fixation group, representing a statistically significant difference (P<0.05). CONCLUSION: Both external fixation and plate internal fixation are effective methods for the treatment of middle and distal tibia fractures. External fixation exhibits the advantage of less surgical trauma and a lower incidence of complications.

JMJD6 protects against isoproterenol-induced cardiac hypertrophy via inhibition of NF-κB activation by demethylating R149 of the p65 subunit.

Histone modification plays an important role in pathological cardiac hypertrophy and heart failure. In this study we investigated the role of a histone arginine demethylase, Jumonji C domain-containing protein 6 (JMJD6) in pathological cardiac hypertrophy. Cardiac hypertrophy was induced in rats by subcutaneous injection of isoproterenol (ISO, 1.2 mg·kg-1·d-1) for a week. At the end of the experiment, the rats underwent echocardiography, followed by euthanasia and heart collection. We found that JMJD6 levels were compensatorily increased in ISO-induced hypertrophic cardiac tissues, but reduced in patients with heart failure with reduced ejection fraction (HFrEF). Furthermore, we demonstrated that JMJD6 overexpression significantly attenuated ISO-induced hypertrophy in neonatal rat cardiomyocytes (NRCMs) evidenced by the decreased cardiomyocyte surface area and hypertrophic genes expression. Cardiac-specific JMJD6 overexpression in rats protected the hearts against ISO-induced cardiac hypertrophy and fibrosis, and rescued cardiac function. Conversely, depletion of JMJD6 by single-guide RNA (sgRNA) exacerbated ISO-induced hypertrophic responses in NRCMs. We revealed that JMJD6 interacted with NF-κB p65 in cytoplasm and reduced nuclear levels of p65 under hypertrophic stimulation in vivo and in vitro. Mechanistically, JMJD6 bound to p65 and demethylated p65 at the R149 residue to inhibit the nuclear translocation of p65, thus inactivating NF-κB signaling and protecting against pathological cardiac hypertrophy. In addition, we found that JMJD6 demethylated histone H3R8, which might be a new histone substrate of JMJD6. These results suggest that JMJD6 may be a potential target for therapeutic interventions in cardiac hypertrophy and heart failure.

Diagnosis of left anterior descending branch-right ventricular fistula with giant coronary artery aneurysm by contrast echocardiography: A case report.

BACKGROUND: Coronary fistulae are communications between a coronary artery and a heart chamber or vessel. The final diagnosis is usually made by coronary angiography or computed tomographic (CT) angiography. Here we report a case by employing contrast echocardiography in diagnosis of a giant coronary aneurysm with right ventricle (RV) fistula. CASE PRESENTATION: The patient, a 29-year-old woman, referred to our institution with a complaint of palpitation occasionally. Transthoracic echocardiogram showed a spherical, echogenic structure in the apex of RV. Proximal to the aneurysm, the left anterior descending branch (LAD) remained enlarged (8-9 mm) and showed a fistulous communication with the echogenic structure. A contrast echocardiography was performed, and 4-5 cardiac cycle after the left ventricle was enhanced, the echogenic structure started to become more prominent and several fistulae were seen between RV and the echogenic structure. Computed tomography (CT) angiography and coronary angiography confirmed the dilation (9 mm in diameter) of the LAD with an aneurysm at the distal segment of the LAD, with a small amount of iodinated contrast agent flowing into the subsequent region of the RV, thereby characterizing a LAD-to-RV fistula. CONCLUSION: The final diagnosis of fistula is usually made by coronary angiography or CT angiography. However, contrast echocardiography is also a well-established method for the demonstration of intracardiac shunting. In this case, the contrast echocardiography clearly revealed one of the fistulae between the aneurysm and RV.

Machine Learning-Based Risk Model for Predicting Early Mortality After Surgery for Infective Endocarditis.

Background The early mortality after surgery for infective endocarditis is high. Although risk models help identify patients at high risk, most current scoring systems are inaccurate or inconvenient. The objective of this study was to construct an accurate and easy-to-use prediction model to identify patients at high risk of early mortality after surgery for infective endocarditis. Methods and Results A total of 476 consecutive patients with infective endocarditis who underwent surgery at 2 centers were included. The development cohort consisted of 276 patients. Eight variables were selected from 89 potential predictors as input of the XGBoost model to train the prediction model, including platelet count, serum albumin, current heart failure, urine occult blood ≥(++), diastolic dysfunction, multiple valve involvement, tricuspid valve involvement, and vegetation >10 mm. The completed prediction model was tested in 2 separate cohorts for internal and external validation. The internal test cohort consisted of 125 patients independent of the development cohort, and the external test cohort consisted of 75 patients from another center. In the internal test cohort, the area under the curve was 0.813 (95% CI, 0.670-0.933) and in the external test cohort the area under the curve was 0.812 (95% CI, 0.606-0.956). The area under the curve was significantly higher than that of other ensemble learning models, logistic regression model, and European System for Cardiac Operative Risk Evaluation II (all, P<0.01). This model was used to develop an online, open-access calculator (http://42.240.140.58:1808/). Conclusions We constructed and validated an accurate and robust machine learning-based risk model to predict early mortality after surgery for infective endocarditis, which may help clinical decision-making and improve outcomes.

Belumosudil, ROCK2-specific inhibitor, alleviates cardiac fibrosis by inhibiting cardiac fibroblasts activation.

Cardiac fibrosis is thought to be the hallmark of pathological hypertrophic remodeling, of which the myofibroblast transdifferentiation is the key cell biological event. However, there is still no specific and effective therapeutic agent approved for cardiac fibrosis. To investigate the effects of belumosudil, the first ρ-associated kinase-2 (ROCK2)-specific inhibitor, on cardiac hypertrophy, fibrosis, and dysfunction induced by pressure overload, the transverse aortic constriction (TAC) or sham operation was carried out on wild-type C57BL/6 mice (male, 6-8 wk old) under pentobarbital anesthesia. After that, mice were randomly divided into three groups: sham operation + vehicle, TAC + vehicle, TAC + 50 mg·kg-1·day-1 belumosudil. We found that belumosudil effectively ameliorated cardiac hypertrophy, fibrosis, and dysfunction in TAC mice. To elucidate the underlying mechanism, we inhibited the expression of ROCK2 in vitro by either belumosudil or siRNA. We showed that the inhibition of ROCK2 by either belumosudil or knockdown suppressed cardiac fibroblasts activation and proliferation significantly induced by transforming growth factor-ß1 (TGF-ß1). Furthermore, our study confirmed ROCK2 mediates cardiac fibrosis by interacting with TGF-ß1/mothers against decapentaplegic homolog 2 (Smad2) pathway. Taken together, we demonstrated that belumosudil ameliorates cardiac hypertrophy and fibrosis induced by TAC via inhibiting cardiac fibroblasts activation. In conclusion, belumosudil may be a promising therapeutic drug for cardiac hypertrophy and fibrosis induced by myocardial pressure overload.NEW & NOTEWORTHY Although ρ-associated kinase-2 (ROCK2) is the main isoform of ρ-associated kinases (ROCKs) in the heart and more important in cardiac hypertrophy and fibrosis than ρ-associated kinase-1 (ROCK1), there has not been any pharmacological approach to inhibit ROCK2 selectively. Our study demonstrates for the first time that belumosudil, the first ROCK2-specific inhibitor, effectively ameliorates cardiac hypertrophy, fibrosis, and dysfunction induced by TAC via inhibiting cardiac fibroblasts activation.

A modified beagle model of inducible atrial fibrillation using a right atrium pacemaker

Abstract Objective: To modify the chronic atrial fibrillation of atrial tachycardia pacing in beagles with a homemade pacemaker placed outside the body and to evaluate connective tissue growth factor and fibrosis of atrial tissue in our modified atrial tachycardia pacing beagle model. Methods: Twelve adult beagles of either sex were randomly divided into an atrial tachycardia pacing group and a control group (n=6 in each group). We performed the temporary pacemaker implantation at the right atrial appendage and put the pacemaker into the pocket of dog clothing in the atrial tachycardia pacing group. After eight weeks of atrial tachycardia pacing, the electrocardiography, transthoracic echocardiography, hematoxylin-eosin staining, and Masson's staining of the right atrial appendages were performed along with the immunohistochemistry, quantitative real-time polymerase chain reaction, and Western blot analysis of connective tissue growth factor, collagen I, and collagen III. Results: In the atrial tachycardia pacing group, atrial fibrillation was induced in five beagles (83.3%); the left atrium enlarged significantly; more canines had mitral regurgitation; and the Masson's staining, quantitative real-time polymerase chain reaction, and Western blot results demonstrated more obvious fibrosis of the left atrium. Conclusion: The modified beagle model of atrial fibrillation using a right atrium pacemaker outside the body was effective, increased connective tissue growth factor and collagen I messenger ribonucleic acid overexpression, and induced atrial fibrosis.

Retaining mTeSR1 Medium during Hepatic Differentiation Facilitates Hepatocyte-Like Cell Survival by Decreasing Apoptosis.

BACKGROUND/AIMS: Hepatocyte-like cells derived from human pluripotent stem cells could be an important cell source for hepatocyte transplantation. The present study investigated the effect of retaining mTeSR1 medium during hepatic differentiation on hepatocyte-like cells in vitro. METHODS: Human embryonic stem cell line H1 were treated with activin A and bone morphogenetic protein 4 (BMP4) for definitive endoderm (DE) cell induction and subsequently treated with BMP2 and fibroblast growth factor 4 (FGF4) for early hepatic cell induction. Hepatocyte growth factor (HGF) and fibroblast growth factor (KGF) were added for early hepatic cell expansion and then mixed with oncostatin-M for maturation. During DE induction, 0%, 25%, 50% and 75% concentrations of mTeSR1 medium were separately added for early hepatic induction and expansion. For optimization, the expression levels of SRY-related HMG-box 17 (SOX17) and forkhead box A2 (FOXA2) at day 4, alpha fetoprotein (AFP) and hepatocyte nuclear factor 4α (HNF4α) at day 15, and albumin (ALB) at day 25 were quantified in differentiated cells by qRT-PCR. The ALB-positive cell proportion was measured by flow cytometry. Functional tests including ALB secretion and indocyanine green (ICG) angiography uptake and release by ELISA, urea production by urea assay kit, and glycogen storage ability by periodic acid Schif reaction (PAS) staining were performed in the differentiated cells. The induced pluripotent stem (iPS) cells were used to examine whether the optimized method was suitable for differentiating iPS cells. DE and hepatic markers were detected by immunostaining, and functional testing was performed as described above. Flow cytometry with an Annexin V-FITC apoptosis detection kit and fluorescence microscopy with Hoechst 33258 were used to analyze apoptosis in differentiated cells derived from H1 cells. RESULTS: All differentiated cells with retention of 0%, 25%, 50% and 75% mTeSR1 expressed SOX17, FOXA2, AFP, HNF4α, and ALB, while higher expression levels were observed in differentiated cells in the 0% and 25% groups. The flow cytometry results showed that the proportion of ALB-positive differentiated cells derived from H1 cells was higher in the 25% mTeSR1 group than in other groups. However, no significant difference in ALB secretion, urea production, ICG uptake and release and glycogen storage ability was detected between the 25% and 0% groups. The iPS cells could differentiate into hepatocyte-like cells with 25% mTeSR1 retention. The apoptosis ratio of differentiated cells was lower in the 25% mTeSR1 group than in the 0% mTeSR1 group. CONCLUSION: Retaining 25% mTeSR1 medium during hepatic differentiation has been proposed to increase the percentage of ALB-positive cells and cell survival by decreasing cell apoptosis.

Genotype-Guided Warfarin Dosing in Patients With Mechanical Valves: A Randomized Controlled Trial.

BACKGROUND: The clinical utility of genotype-guided warfarin dosing remains controversial. The objective of this trial was to evaluate the efficacy and safety of genotype-guided warfarin dosing in East Asians. METHODS: A double-blind, randomized control trial was performed to compare a genotype-guided dosing algorithm (CYP2C9, VKORC1, and CYP4F2) with a clinical-guided one in the initiation treatment for patients with mechanical heart valves. The primary outcomes included the time to reach a stable dose and the percentage of time in the therapeutic range (TTR). RESULTS: Two hundred one patients were randomly assigned to treatment, 101 to control and 100 to study. The major bleeding and thromboembolic event-free rate in the study group was 97.0% (95% confidence interval: 90.9% to 99.2%). Compared with the control group, the study group shortened the time to reach a stable dose (mean: 42.09 ± 23.655 days versus 33.52 ± 20.044 days, p = 0.009). The TTRs were 47.257% and 47.461% in the control and study group (p = 0.941), respectively. Patients with the CYP2C9 *1/*3 genotype had higher international normalized ratio (INR) variability than patients with the CYP2C9 *1/*1 genotype (p = 0.024). Compared with normal and sensitive responders, the highly sensitive responders were at increased risk of an INR of 4.0 or greater (p < 0.05). CONCLUSIONS: The genotype-guided warfarin dosing was safe and might be more efficient for the time to reach a stable dose. Pharmacogenomic testing might be beneficial to identify the patients with the CYP2C9 *1/*3 genotype and the highly sensitive responders, who were in the high-risk subgroup of patients with mechanical heart valves. An appropriately powered study is needed to further confirm these findings.

Imatinib attenuates cardiac fibrosis by inhibiting platelet-derived growth factor receptors activation in isoproterenol induced model.

Cardiac fibrosis is a significant global health problem with limited treatment choices. Although previous studies have shown that imatinib (IMA) inhibited cardiac fibrosis, the anti-fibrotic mechanisms have not been clearly uncovered. The aim of this study is to evaluate whether IMA attenuates cardiac fibrosis by inhibiting platelet-derived growth factor receptors (PDGFR) on isoproterenol (ISO)-induced mice. Adult male C57BL/6 mice were treated with vehicle or ISO ± IMA for one week. After echocardiography examination, the hearts of mice were used for histopathologic, RT-qPCR, and western blot analyses. We found that the ventricular wall thickness, cardiac hypertrophy, and apoptosis were enhanced following ISO treatment. IMA decreased the left ventricular wall thickness, prevented hypertrophy, and inhibited apoptosis induced by ISO. In addition, IMA attenuated the accumulation of collagens and α-smooth muscle actin (α-SMA) (the markers of fibrosis) caused by ISO treatment. Moreover, the expression of fibrosis related genes, and the phosphorylation of PDGFRs in ISO-treated mice hearts were inhibited by IMA as well. However, IMA did not change the expression of the matrix metalloproteinase-9 (MMP-9) in ISO-treated hearts. Furthermore, IMA reduced the expressions of collagens as well as α-SMA caused by activation of PDGFRα in cardiac fibroblasts. Taken together, our data demonstrate that IMA attenuated the cardiac fibrosis by blocking the phosphorylation of PDGFRs in the ISO-induced mice model. This study indicates that IMA could be a potentially therapeutic option for cardiac fibrosis in clinical application.

Foxo3 circular RNA promotes cardiac senescence by modulating multiple factors associated with stress and senescence responses.

AIMS: Circular RNAs are a subclass of non-coding RNAs detected within mammalian cells. This study was designed to test the roles of a circular RNA circ-Foxo3 in senescence using in vitro and in vivo approaches. METHODS AND RESULTS: Using the approaches of molecular and cellular biology, we show that a circular RNA generated from a member of the forkhead family of transcription factors, Foxo3, namely circ-Foxo3, was highly expressed in heart samples of aged patients and mice, which was correlated with markers of cellular senescence. Doxorubicin-induced cardiomyopathy was aggravated by ectopic expression of circ-Foxo3 but was relieved by silencing endogenous circ-Foxo3. We also found that silencing circ-Foxo3 inhibited senescence of mouse embryonic fibroblasts and that ectopic expression of circ-Foxo3 induced senescence. We found that circ-Foxo3 was mainly distributed in the cytoplasm, where it interacted with the anti-senescent protein ID-1 and the transcription factor E2F1, as well as the anti-stress proteins FAK and HIF1α. CONCLUSION: We conclude that ID-1, E2F1, FAK, and HIF1α interact with circ-Foxo3 and are retained in the cytoplasm and could no longer exert their anti-senescent and anti-stress roles, resulting in increased cellular senescence.

Retrograde Cerebral Perfusion Results in Better Perfusion to the Striatum Than the Cerebral Cortex During Deep Hypothermic Circulatory Arrest: A Microdialysis Study.

It remains controversial whether contemporary cerebral perfusion techniques, utilized during deep hypothermic circulatory arrest (DHCA), establish adequate perfusion to deep structures in the brain. This study aimed to investigate whether selective antegrade cerebral perfusion (SACP) or retrograde cerebral perfusion (RCP) can provide perfusion equally to various anatomical positions in the brain using metabolic evidence obtained from microdialysis. Eighteen piglets were randomly assigned to 40 min of circulatory arrest (CA) at 18°C without cerebral perfusion (DHCA group, n = 6) or with SACP (SACP group, n = 6) or RCP (RCP group, n = 6). Microdialysis parameters (glucose, lactate, pyruvate, and glutamate) were measured every 30 min in cortex and striatum. After 3 h of reperfusion, brain tissue was harvested for Western blot measurement of α-spectrin. After 40 min of CA, the DHCA group showed marked elevations of lactate and glycerol and a reduction in glucose in the microdialysis perfusate (all P < 0.05). The changes in glucose, lactate, and glycerol in the perfusate and α-spectrin expression in brain tissue were similar between cortex and striatum in the SACP group (all P > 0.05). In the RCP group, the cortex exhibited lower glucose, higher lactate, and higher glycerol in the perfusate and higher α-spectrin expression in brain tissue compared with the striatum (all P < 0.05). Glutamate showed no difference between cortex and striatum in all groups (all P > 0.05). In summary, SACP provided uniform and continuous cerebral perfusion to most anatomical sites in the brain, whereas RCP resulted in less sufficient perfusion to the cortex but better perfusion to the striatum.

MicroRNA profiling of the intestine during hypothermic circulatory arrest in swine.

AIM: To perform a profiling analysis of changes in intestinal microRNA (miRNA) expression during hypothermic circulatory arrest (HCA). METHODS: A total of eight piglets were randomly divided into HCA and sham operation (SO) groups. Under general anesthesia, swine in the HCA group were subjected to hypothermic cardiopulmonary bypass at 24 °C followed by 80 min of circulatory arrest, and the reperfusion lasted for 180 min after cross-clamp removal. The counterparts in the SO group were only subjected to median sternotomy. Histopathological analysis was used to detect mucosal injury, and Pick-and-Mix custom miRNA real-time polymerase chain reaction (PCR) panels containing 306 unique primer sets were utilized to assay unpooled intestinal samples harvested from the two groups. RESULTS: The intestinal mucosa of the animals that were subjected to 24 °C HCA exhibited representative ischemic reperfusion injury of grade 2 or 3 according to the Chiu score. Such intestinal mucosal injuries, with the subepithelial space and epithelial layer lifting away from the lamina propria, were accompanied by shortened and irregular villi. On the contrary, the intestinal mucosa remained normal in the sham-operated animals. In total, twenty-five miRNAs were differentially expressed between the two groups (15 upregulated and 10 downregulated in the HCA group). Among these, eight miRNAs (miR-122, miR-221-5p, miR-31, miR-421-5p, miR-4333, miR-499-3p, miR-542 and let-7d-3p) were significantly dysregulated (four higher and four lower). The expression of miR-122 was significantly (5.37-fold) increased in the HCA group vs the SO group, indicating that it may play a key role in HCA-induced mucosal injury. CONCLUSION: Exposure to HCA caused intestinal miRNA dysregulation and barrier dysfunction in swine. These altered miRNAs might be related to the protection or destruction of the intestinal barrier.

Ellagic acid prevents monocrotaline-induced pulmonary artery hypertension via inhibiting NLRP3 inflammasome activation in rats.

BACKGROUND: Pulmonary artery hypertension (PAH) is characterized by vascular remodeling, high pulmonary blood pressure, and right ventricular hypertrophy. Oxidative stress, inflammation and pulmonary artery remodeling are important components in PAH. Ellagic acid (EA) is a phenolic compound with anti-oxidative, anti-inflammatory, and anti-proliferative properties. This study aimed to investigate whether EA could prevent the development of monocrotaline (MCT)-induced PAH in rats. METHODS: Male Sprague-Dawley rats received EA (30 and 50mg/kg/day) or vehicle one day after a single-dose of monocrotaline (MCT, 60mg/kg). Hemodynamic changes, right ventricular hypertrophy, and lung morphological features were assessed 4weeks later. Activation of the NLRP3 (NACHT, LRR, and PYD domain-containing protein 3) inflammasome pathway in the lungs was assessed using Western blot analysis. RESULTS: MCT induced PAH, oxidative stress, and NLRP3 inflammasome activation in vehicle-treated rats. EA reduced the right ventricle systolic pressure, the right ventricular hypertrophy and the wall thickness/external diameter ratio of the pulmonary arteries compared with vehicle. EA also inhibited the MCT-induced elevation of oxidative stress, NLRP3, and caspase-1, IL-ß in the lungs and the elevated levels of brain natriuretic peptide (BNP) and inflammatory cytokines in serum. CONCLUSIONS: Ellagic acid ameliorates monocrotaline-induced pulmonary artery hypertension via exerting its anti-oxidative property inhibiting NLRP3 inflammasome signal pathway in rats.

Selective antegrade cerebral perfusion attenuating the TLR4/NF-κB pathway during deep hypothermia circulatory arrest in a pig model.

OBJECTIVES: The alteration of the Toll-like receptor/nuclear factor-kappa B (TLR4/NF-κB) signaling pathway during deep hypothermia circulatory arrest (DHCA) has not yet been defined. The aim of this study was to explore the expression of the TLR4/NF-κB pathway cytokine in cerebral injury resulting from DHCA as well as the effect of selective antegrade cerebral perfusion (SACP) on TLR4/NF-κB pathway expression. METHODS: Twelve pigs were randomly assigned to DHCA alone (n = 6) or DHCA with SACP (n = 6) at 18°C for 80 min. Serum interleukin (IL)-6 was assayed by ELISA. Apoptosis and NF-κB proteins were detected by fluorescence TUNEL and Western blot, respectively. The level of TLR4 mRNA and protein were determined through qRT-PCR and Western blot. RESULTS: The serum IL-6 level of the SACP group was significantly lower than that of the DHCA group at the end of circulation arrest and experimentation. Apoptotic index and NF-κB protein were apparently lower in SACP animals (p < 0.05). Compared to the DHCA group, the levels of TLR4 protein and mRNA in the SACP group were lower with significance (p < 0.05). CONCLUSIONS: The TLR4/NF-κB signaling pathway plays a critical role in the pathogenesis of DHCA cerebral injury. Attenuation of the TLR4/NF-κB inflammatory cytokines probably contributes to the neuroprotective effect of SACP. The TLR4/NF-κB inflammatory signaling pathway may be a novel therapeutic target for developing a new strategy for neuroprotection in DHCA.

Comparative expression profiles of microRNA in left and right atrial appendages from patients with rheumatic mitral valve disease exhibiting sinus rhythm or atrial fibrillation.

BACKGROUND: The atrial fibrillation (AF) associated microRNAs (miRNAs) were found in the right atrium (RA) and left atrium (LA) from patients with rheumatic mitral valve disease (RMVD). However, most studies only focus on the RA; and the potential differences of AF-associated miRNAs between the RA and LA are still unknown. The aim of this study was to perform miRNA expression profiles analysis to compare the potential differences of AF-associated miRNAs in the right atrial appendages (RAA) and left atrial appendages (LAA) from RMVD patients. METHODS: Samples tissues from the RAA and LAA were obtained from 18 RMVD patients (10 with AF) during mitral valve replacement surgery. From these tissues, miRNA expression profiles were created and analyzed using a human miRNA microarray. Then, the results were validated using qRT-PCR analysis for 12 selected miRNAs. Finally, potential targets of 10 validated miRNAs were predicted and their functions and potential pathways were analyzed using the miRFocus database. RESULTS: In RAA, 65 AF-associated miRNAs were found and significantly dysregulated (i.e. 28 miRNAs were up-regulated and 37 were down-regulated). In LAA, 42 AF-associated miRNAs were found and significantly dysregulated (i.e. 22 miRNAs were up-regulated and 20 were down-regulated). Among these AF-associated miRNAs, 23 of them were found in both RAA and LAA, 45 of them were found only in RAA, and 19 of them were found only in LAA. Finally, 10 AF-associated miRNAs validated by qRT-PCR were similarly distributed in RAA and LAA; 3 were found in both RAA and LAA, 5 were found only in RAA, and 2 were found only in LAA. Potential miRNA targets and molecular pathways were identified. CONCLUSIONS: We have found the different distributions of AF-associated miRNAs in the RAA and LAA from RMVD patients. This may reflect different miRNA mechanisms in AF between the RA and LA. These findings may provide new insights into the underlying mechanisms of AF in RMVD patients.

Is selective antegrade cerebral perfusion superior to retrograde cerebral perfusion for brain protection during deep hypothermic circulatory arrest? Metabolic evidence from microdialysis.

OBJECTIVES: This study aimed to investigate whether selective antegrade cerebral perfusion or retrograde cerebral perfusion is a better technique for brain protection in deep hypothermic circulatory arrest by obtaining metabolic evidence from microdialysis. DESIGN: Randomized, animal study. SETTING: Assisted circulation laboratory. SUBJECTS: Eighteen piglets of either sex (9.8 ± 3.1 kg). INTERVENTIONS: Animals were randomly assigned to 40 minutes of circulatory arrest at 18°C without cerebral perfusion (deep hypothermic circulatory arrest group, n = 6) or with selective antegrade cerebral perfusion (selective antegrade cerebral perfusion group, n = 6) or retrograde cerebral perfusion (retrograde cerebral perfusion group, n = 6). Reperfusion was continued for 3 hours. MEASUREMENTS AND MAIN RESULTS: Microdialysis (glucose, lactate, pyruvate, and glycerol) variables in the cortex dialysate were measured every 30 minutes. Intracerebral pressure and serum S-100 levels were also monitored. After 3 hours of reperfusion, cortical tissue was harvested for terminal deoxynucleotidyl transferase dUTP nick-end labeling staining. After 40 minutes of circulatory arrest, the deep hypothermic circulatory arrest group presented marked elevations of intracerebral pressure, and serum S-100 levels were higher in the deep hypothermic circulatory arrest group than in the other two groups (p < 0.001, respectively). The selective antegrade cerebral perfusion group exhibited higher glucose, lower lactate, and lower glycerol levels and a lower lactate-to-pyruvate ratio in comparison to the deep hypothermic circulatory arrest group (p < 0.05, respectively); the retrograde cerebral perfusion group had lower lactate and glycerol levels and a lower lactate-to-pyruvate ratio (p < 0.05, respectively) but similar glucose levels compared to deep hypothermic circulatory arrest alone. Furthermore, selective antegrade cerebral perfusion provided better preservation of energy and cell integrity than retrograde cerebral perfusion with higher glucose and lower glycerol levels (p < 0.05, respectively). After 3 hours of reperfusion, fewer apoptotic neurons were found in selective antegrade cerebral perfusion animals than in the other two groups (p < 0.05, respectively). CONCLUSIONS: Both selective antegrade cerebral perfusion and retrograde cerebral perfusion were superior to deep hypothermic circulatory arrest alone during circulatory arrest. Retrograde cerebral perfusion was a moderate technique that had similar advantages with regard to less cerebral edema, better clearance of metabolic waste, and lower levels of biomarkers of injury than selective antegrade cerebral perfusion, but its capacity for energy preservation, maintenance of cellular integrity, and protection against apoptosis was lower than that of selective antegrade cerebral perfusion.

Dynamics of interstitial calcium in rat myocardial ischemia reperfusion injury in vivo.

Intracellular calcium overload is a key factor for myocardial ischemia reperfusion injury (IR). However, there was no report for interstitial calcium concentration dynamics. We investigated the interstitial calcium dynamics in rat myocardial IR model in vivo. A microdialysis system was involved, and the time delay of the system and recovery time was introduced and tested with a fluids switching method. Twelve SD rats were divided into IR or control group. Myocardial IR was induced by ligating (20 min) then releasing (60 min) the suture underlying left anterior descending branch. Mycrodialyisis probe was implanted into the left ventricular myocardium perfusion area for occlusion. Dialysate samples were collected every 10 min. Dialysate calcium concentration was detected with an atomic absorption spectrophotometer. Recovery time for the microdialysis system was 20 min, and recovery rate was 16%. Dialysate calcium concentration showed no changes during ischemia, descended immediately after reperfusion, reached the lowest level (67% of baseline value) 20 min after reperfusion, then escalated slowly. Recovery time was an important parameter for mycrodialysis technique, and it should not be neglected and needed to be tested. Our data suggest that interstitial calcium concentration in rats with myocardial IR in vivo kept steady in ischemia, descended rapidly at the initial reperfusion, then rebounded slowly. In conclusion, we introduced the concept of recovery time for microdialysis and provided a simple testing method.

Atrial fibrillation alters the microRNA expression profiles of the left atria of patients with mitral stenosis.

BACKGROUND: Structural changes of the left and right atria associated with atrial fibrillation (AF) in mitral stenosis (MS) patients are well known, and alterations in microRNA (miRNA) expression profiles of the right atria have also been investigated. However, miRNA changes in the left atria still require delineation. This study evaluated alterations in miRNA expression profiles of left atrial tissues from MS patients with AF relative to those with normal sinus rhythm (NSR). METHODS: Sample tissues from left atrial appendages were obtained from 12 MS patients (6 with AF) during mitral valve replacement surgery. From these tissues, miRNA expression profiles were created and analyzed using a human miRNA microarray. Results were validated via reverse-transcription and quantitative PCR for 5 selected miRNAs. Potential miRNA targets were predicted and their functions and potential pathways analyzed via the miRFocus database. RESULTS: The expression levels of 22 miRNAs differed between the AF and NSR groups. Relative to NSR patients, in those with AF the expression levels of 45% (10/22) of these miRNAs were significantly higher, while those of the balance (55%, 12/22) were significantly lower. Potential miRNA targets and molecular pathways were identified. CONCLUSIONS: AF alters the miRNA expression profiles of the left atria of MS patients. These findings may be useful for the biological understanding of AF in MS patients.