Two Acentric Zn-Based l-Tartrates with Moderate Second Harmonic Generation Responses and Large Birefringence.

The discovery of novel organic-inorganic hybrid nonlinear optical (NLO) crystal materials holds great potential in advancing laser science and technology as they offer a wide range of benefits including easy synthesis, structural versatility, and high hyperpolarizability. Herein, the integration of l-tartaric acid (L-C4H6O6) and ZnSO4 gave rise to two acentric Zn-based organic-inorganic hybrid crystals, namely, Zn2(H2O)2(C4H4O6)2·3H2O (Zn-LT) and Zn2(H2O)(C4H4O6)(C4H6O6)(SO4)·4H2O (Zn-LTS). They both feature layered structures constructed by [ZnO6] octahedron, l-C4H6O6/l-C4H4O62-, water molecule, or [SO4] tetrahedron. Interestingly, they possess moderate second-order NLO effects of 0.28 × KH2PO4 (Zn-LT) and 0.57 × KH2PO4 (Zn-LTS), large birefringence of 0.075 (Zn-LT) and 0.069 (Zn-LTS), suggesting that the introduction of [SO4] groups with intrinsically weak polarizability and weak optical anisotropy induces the enhancement of the NLO effect while without reducing birefringence much. In addition, both of them display UV cutoff edges near 210 nm, indicating their potential as NLO crystals applied in the UV and solar-blind region.

Surgical repair of unilateral absence of pulmonary artery in children with pulmonary hypertension: a single-center retrospective study.

Background: The early diagnosis of unilateral absence of pulmonary artery (UAPA) in children offers an opportunity for effective intervention. Due to the lack of clinical evidence, a consensus regarding surgical treatment has yet to be reported. The aim of this study is to evaluate the effectiveness and safety of pulmonary artery (PA) reconstruction with a "two-segment" technique to repair UAPA in patients with pulmonary hypertension. Methods: Intraoperatively, the ligamentum arteriosum connecting the innominate artery and distal PA was dissected and occluded. A conduit created by fresh autologous pericardium formed the first "segment" of the neo-PA. The second "segment" was a Gore vascular graft with integrated rings anastomosed between the proximal end of the pericardial conduit and the main pulmonary artery (MPA). Results: A total of five consecutive patients were included, and the absent PA was successfully reconstructed using the "two-segment" technique in all patients. Following revascularization, the direct measurement of the pressure in MPA during the operation showed that the average mean pulmonary artery pressure (mPAP) decreased from 31.3±16.0 to 16.8±4.2 mmHg (P=0.047). The average mPAP/radial mean arterial pressure (rMAP) ratio decreased from 0.59±0.27 preoperatively to 0.30±0.10 postoperatively (P=0.028). The mean follow-up period was 18.85±4.67 months. The median diameter of the reconstructed PA (pericardial segment) measured by transthoracic echocardiography (TTE) was 6.1 mm. One patient safely underwent a redo operation to repair relative stenosis in the neo-PA. Conclusions: Early PA reconstruction may effectively alleviate pulmonary hypertension in children with UAPA. The "two-segment" technique is safe and can facilitate potential redo pulmonary arterioplasty. Anticoagulation and antiplatelet therapy, as well as frequent follow-up, is required after the operation.

REV-ERB is essential in cardiac fibroblasts homeostasis.

REV-ERB agonists have shown antifibrotic effects in the heart and other organs. The function of REV-ERB in the cardiac fibroblasts remains unstudied. Here, we characterize the functional difference of REV-ERB in mouse embryonic fibroblasts and cardiac fibroblasts using genetic deletion of REV-ERBα and ß in vitro. We show that REV-ERB α/ß double deleted cardiac fibroblasts have reduced viability and proliferation, but increased migration and myofibroblasts activation. Thus, REV-ERB α/ß has essential cell-autonomous role in cardiac fibroblasts in maintaining them in a healthy, quiescent state. We also show that existing REV-ERB agonist SR9009 strongly suppresses cardiac fibroblasts activation but in a REV-ERB-independent manner highlighting the need to develop novel REV-ERB agonists for treating cardiac fibrosis.

Risk Factors for Aortic Regurgitation Progression After Repair of Sinus of Valsalva Aneurysm.

BACKGROUND: The main treatment for a ruptured sinus of Valsalva aneurysm (SVA) is surgical repair. Postoperative progression of aortic regurgitation (AR) following SVA repair increases the risk of reoperation, which decreases the long-term survival. Thus, identifying the risk factors for postoperative AR progression is of great significance. METHODS: Adult patients who were diagnosed with ruptured SVA and underwent surgical repair at the current centre were reviewed. Necessary data in the institutional database were extracted. The perioperative and follow-up assessments of the aortic valve by transthoracic echocardiography were also obtained. The aortic regurgitation progression was grouped into three categories: newly developing, recurrence, and worsening. Sixteen (16) variables were screened to identify potential risk factors by univariate logistic regression analysis or Chi-squared test. Variables with p-values <0.1 were further analysed by multivariate logistic regression models to find independent risk factors. RESULTS: A total of 198 consecutive patients from June 2006 to January 2018 were included. The overall incidence of postoperative AR progression was 19.2% (38 of 198). After the univariate analysis, SVA originating from the right coronary sinus, coexisting with ventricular septal defect, larger diameter of aortic annulus, and larger cardiothoracic ratio were screened as potential risk factors. Multivariate analysis indicated that coexisting with a ventricular septal defect (VSD) (OR, 2.82; 95% CI, 1.217-6.532; p=0.016) and larger cardiothoracic ratio (OR, 1.061; 95% CI, 1.001-1.124; p=0.047) were independent risk factors for postoperative AR progression. CONCLUSIONS: To prevent postoperative AR progression after surgical repair, more careful inspection and appropriate surgical techniques are necessary for patients coexisting with VSD or with a larger cardiothoracic ratio.

Central and Peripheral Cannulation for Cardiopulmonary Bypass in Fetal Sheep: A Comparative Study.

Objective: In-utero correction is an option for treatment of critical congenital heart diseases (CHDs). Fetal cardiac surgery for CHDs is dependent on the reliable use of fetal cardiopulmonary bypass (CPB), but this technology remains experimental. In this study, we established fetal CPB models with central and peripheral cannulation to explore the differences between the two cannulation strategies. Methods: Ten fetal sheep with 90-110 gestational days were randomized into central cannulation (n = 5) and peripheral cannulation (n = 5) groups. All fetal CPB models were successfully established. At each time point (0, 30, and 60 min after initiation of CPB), echocardiography was performed. Blood samples were also collected for blood gas analysis and tests of myocardial enzymes and liver and kidney function. Results: In the central cannulation group, right ventricular Tei index significantly increased (p = 0.016) over time. Compared with the peripheral cannulation group, the left ventricular Tei index of the central cannulation group was significantly higher (1.96 ± 0.31 vs. 0.45 ± 0.19, respectively; p = 0.028) and the stroke volume was lower (0.46 ± 0.55 vs. 2.13 ± 0.05, respectively; p = 0.008) at 60 min after CPB. Levels of liver and kidney injury markers and of acid-base balance, including alanine aminotransferase (ALT), aspartate aminotransferase/ALT ratio, blood urea nitrogen (BUN), BUN/creatinine ratio, base excess and bicarbonates, were significantly higher for peripheral than for central cannulation. Other important physiologic parameters, including heart rate, blood pressure, myocardial enzymes, umbilical artery beat index and resistance index, left ventricular Tei index, and left and right ventricular stroke volume, were comparable between the two groups. Conclusions: Both central and peripheral cannulations can be used to establish fetal CPB models. Central cannulation causes more adverse impacts for cardiac function, whereas peripheral cannulation is more susceptible to complications related to inadequate organ perfusion.

Comparison of clinical results between percutaneous closure and surgical repair of ruptured sinus of Valsalva aneurysm.

OBJECTIVES: This study was conducted to investigate whether percutaneous closure of ruptured sinus of Valsalva aneurysm (SVA) is as safe and effective as surgery repair. BACKGROUND: Percutaneous closure of ruptured SVA has been becoming an alternative to the traditional surgical repair recently. The reports regarding direct comparison of these two treatment options are scarce. METHODS: The medical records from the institutional database were retrospectively analyzed. A total of 134 patients were reviewed, including 26 patients undergoing percutaneous closure and 108 patients being treated surgically. To reduce the potential bias, 32 patients from Surgical Repair group were selected by propensity score matching. RESULTS: All the ruptured SVAs were successfully closed in each group. No severe procedure-related complications were found in the perioperative period. After matching, there were no significant differences in the baseline clinical characteristics. The median postoperative hospital stays of Matched group were significantly longer than that of Percutaneous Closure group (7 days vs. 1 day, p < .001). Aortic regurgitation, residual shunt and recurrence of SVAs were common complications in both Percutaneous Closure group and Surgical Repair group. CONCLUSIONS: The appropriately selected patients with ruptured SVA could be treated by percutaneous closure with an acceptable risk of short-term complications. Though surgical repair remains the main treatment option for ruptured SVAs, percutaneous closure could be considered in patients with a small-size rupture and no associated cardiac abnormalities.

The enlargement rate of ventricular septal rupture is a risk factor for 30-day mortality in patients with delayed surgery.

BACKGROUND: Postinfarction ventricular septal rupture (VSR) is an uncommon but challenging mechanical complication for surgeons. This study analyzed the impacts of rupture size on surgical outcomes in patients with VSR. METHODS: During a 15-year period, from January 2006 to December 2020, 112 patients underwent repairs of postinfarction VSR. Patient clinical data, including angiographic and echocardiographic findings, operative procedures, early morbidity and mortality, and survival time were collated. Univariable and multivariable analyses were performed to identify the risk factors of 30-day mortality. RESULTS: The 30-day mortality rate was 7.1% for the whole cohort. The mean survival time estimate was 147.2 months [95% confidence interval (CI): 135.6 to 158.9 months], with a 3-year survival rate of 91.2% and a 5-year survival rate of 89.0%. Multivariable analysis revealed that rupture enlargement rate is an independent risk factor of 30-day mortality. The receiver operating characteristic (ROC) curve indicated that the rupture enlargement rate could predicted the 30-day mortality with high accuracy. CONCLUSIONS: Delayed surgery may be considered for patients who respond well to aggressive treatment. The rupture enlargement rate is an independent risk factor for postoperative 30-day morality in patients with delayed VSR repair. Furthermore, the rupture enlargement rate has good predictive value for the prognosis of VSR patients.

Comparison of the effects of coronary artery anastomosis training between senior and junior surgeons.

OBJECTIVE: Many countries are facing a shortage of cardiac surgeons, who are crucial in meeting the demands of growing number of patients in need of coronary artery bypass grafting. This situation poses a serious challenge, especially in China. The purpose of this study is to determine whether cardiac surgeons are suitable for training in coronary artery anastomosis at an earlier stage in their career. METHODS: We divided 12 cardiac surgeons with no prior experience in coronary artery anastomosis into senior and junior groups for training and assessment. All trainees received training in coronary artery anastomosis for a defined period. We performed in vivo and in vitro examinations before and after training, respectively. Additionally, we assessed individual surgical performance of surgeons by using performance rating scores, including different aspects of surgical skills rated on a five-point scale. RESULTS: The post-training scores (overall, junior, senior) were significantly higher than the pre-training scores (overall, junior, and senior). We observed no differences in pre-training and post-training scores between the junior and senior groups. CONCLUSION: Senior surgeons did not had any significant advantages over junior surgeons with respect to coronary artery anastomosis in the absence of training. Junior surgeons achieved the same results as the senior surgeons after training.

A tissue-based simulation model for cardiopulmonary bypass cannulation/decannulation training.

BACKGROUND: Cardiopulmonary bypass is the basis of open heart surgery. Through simulation-based learning, residents may receive structured training of cardiopulmonary bypass techniques. Therefore, we built a high-fidelity, tissue-based simulation model for cardiopulmonary bypass cannulation/decannulation training. METHODS: The core of the model is a whole block of cadaveric animal heart and lung. The discarded membrane oxygenators are used as blood reservoirs. The tubing and suckers recycled from animal experiments are washed and reused. To set up the model, the cadaveric heart and lung are placed into a container of appropriate size. The "arterial" tubing is connected with a pressure gauge, the distal aorta, the superior vena cava, and arterial cannula, respectively. The "venous" tubing is composed of three independent catheters, respectively, for the practice of venous cannulation, for the connection of sucker and for the practice of placing left atrial/ventricular vent. All tubes are installed on the roller pumps to maintain the correct flow direction. A technician should be responsible for operating the heart-lung machine, clamping and releasing the specific segments of tubing, adjusting the pressure, and cooperating with the trainees to practice. RESULTS: Using the simulation model, 18 residents underwent cardiopulmonary bypass techniques training, with an average satisfaction of 8.94 points. The mean score on the overall fidelity of the simulation model assessed by nine experienced cardiothoracic surgeons was 8.67 points. CONCLUSION: The tissue-based simulation model has a certain degree of realism. Cardiac surgery residents can practice necessary cardiopulmonary bypass cannulation/decannulation techniques by this model.

Invasive Hemodynamic Assessment for the Right Ventricular System and Hypoxia-Induced Pulmonary Arterial Hypertension in Mice.

Pulmonary arterial hypertension (PAH) is a chronic and severe cardiopulmonary disorder. Mice are a popular animal model used to mimic this disease. However, the evaluation of right ventricular pressure (RVP) and pulmonary artery pressure (PAP) remains technically challenging in mice. RVP and PAP are more difficult to measure than left ventricular pressure because of the anatomical differences between the left and right heart systems. In this paper, we describe a stable right heart hemodynamic measurement method and its validation using healthy and PAH mice. This method is based on open-chest surgery and mechanical ventilation support. It is a complicated procedure compared to closed chest procedures. While a well-trained surgeon is required for this surgery, the advantage of this procedure is that it can generate both RVP and PAP parameters at the same time, so it is a preferable procedure for the evaluation of PAH models.

An exploration of the surgical skill training curriculum for cardiac surgery residents.

BACKGROUND: A "boot camp" program is commonly adopted in surgical skills training. Due to a shortage of cardiac surgeons, establishment of a well-designed training curriculum for cardiac surgery residents is needed in developing countries. METHODS: We established a comprehensive 3-module training curriculum, including: (1) the cardiopulmonary bypass establishment technique, (2) coronary artery anastomosis and (3) basic surgical skills of thoracoscopy. Each module was designed for one technique, with a training time of 1 week. Each module included theoretical knowledge learning, demonstration by senior surgeons, and practice through simulators and in vivo animal experiment. A series of questionnaires were used to assess the training effect. RESULTS: We organized 50 person-times of training. The overall satisfaction of residents participating in the entire 3-module training was 7.88 points (from a full score of 10 points). The satisfaction of each module was 8.94, 8.13, and 7.63, respectively. The survey suggested the training could increase trainees' confidence in the operation (P < 0.05). Some trainees also proposed some suggestions for the further improvement of the curriculum. CONCLUSIONS: It is feasible to develop a multimodule comprehensive surgical skill training curriculum for cardiac surgery residents in China, whose confidence can be effectively enhanced.

Effects of atrial fibrosis induced by mitral regurgitation on atrial electrophysiology and susceptibility to atrial fibrillation in pigs.

BACKGROUND: The mechanism by which atrial fibrosis leads to the production and maintenance of atrial fibrillation (AF) is unclear. Myocardial biopsies, which have often been used in previous studies, are taken from a single site and do not always reflect the overall condition of atrial fibrosis. AIMS: The aim of this study was to investigate the location of fibrosis in the atria induced by mitral regurgitation (MR) and its effect on atrial electrophysiology and vulnerability to AF. METHODS: Nineteen pigs were divided into three groups. The control group (n=6) underwent a sham operation, and the experimental groups underwent an MR induction operation and were observed for 3 (n=7) or 6 (n=6) months. All the animals were tested for vulnerability to AF. Then, the atria were divided into 12 regions: 6 in the left atrium (LA) and 6 in the right atrium (RA). The conduction velocities (CVs) and effective refractory periods (ERPs) in different regions were examined by electroanatomic mapping, and fibrosis in different regions was examined by Masson staining. RESULTS: With the duration of MR, fibrosis (3.11% ±â€¯0.08% in the control group, 5.85% ±â€¯0.42% in the 3-month group and 8.17% ±â€¯0.23% in the 6-month group, P<.001), vulnerability to AF (0/6 in the control group, 2/7 in the 3-month group and 5/6 in the 6-month group, P<.05) and the effective refractory period (220.1±1.1 ms in the control group, 244.4±1.4 ms in the 3-month group and 289.0±8.9 ms in the 6-month group, P<.001) were increased, while the conduction velocity (1.39±0.16 m/s in the control group, 1.04±0.05 m/s in the 3-month group and 0.89±0.02 m/s in the 6-month group, P<.001) was reduced. These pathophysiological changes were not uniform in different regions of the atria (3.83% ±â€¯0.25% in right atrial fibrosis vs 8.22% ±â€¯0.83% in left atrial fibrosis, P<.001; 5.09% ±â€¯0.34% in the right atrium vs 11.76% ±â€¯0.52% in the left atrium, P<.001). A negative correlation was identified between fibrosis and conduction velocity (P<.001 in the 3-month and 6-month groups), but no correlation was found between fibrosis and the effective refractory period (P=.829 in the 3-month group and P=.093 in the 6-month group). Susceptibility to AF was associated with the dispersion of atrial fibrosis (P=.023). CONCLUSIONS: With the duration of MR, atrial fibrosis increased, and the degree of increase was not uniform among different areas of the atria. The dispersion of atrial fibrosis may contribute to increased susceptibility to AF by influencing the conduction velocity rather than the effective refractory period.

Surgical repair of a ruptured congenital sinus of Valsalva aneurysm: 10-year experience with 286 cases.

OBJECTIVES: Surgical intervention is the main treatment for a ruptured congenital sinus of Valsalva aneurysm (SVA). However, reports on the surgical experience are scarce. We retrospectively analysed the cases of our centre to summarize our 10-year experience. METHODS: A total of 286 patients who were diagnosed with a congenital ruptured SVA and underwent surgical repair between 2007 and 2016 were identified for the analysis. Follow-up data (mean ± standard deviation: 49.6 ± 34.9 months) were obtained from outpatient department records and telephone calls. RESULTS: The SVAs originated from the right coronary sinus (79.7%), the non-coronary sinus (19.6%) and the left coronary sinus (0.7%) but ruptured into the right ventricle (58.4%) and the right atrium (41.3%). The most commonly associated deformities were a ventricular septal defect (46.3%), aortic valve regurgitation (33.2%) and tricuspid regurgitation (20.3%). The SVA defect was closed by direct suturing (9.1%) or patching (90.9%) through an incision in the cardiac chamber involved or a transaortic approach. The mean postoperative hospital stay duration was 7.2 days, and 98.6% of the patients were discharged in New York Heart Association functional class I or II. The incidence rate of short-term complications was 5.7%. There were 4 late deaths, and 9 patients required rehospitalization due to surgery-related events. The estimated 10-year survival rate was greater than 90% according to the Kaplan-Meier survival curve. CONCLUSIONS: Surgical repair is an effective and safe treatment for a ruptured SVA. The majority of patients who undergo surgical repair can survive for a long time.

Efficacy and safety of the convergent atrial fibrillation procedure: a meta-analysis of observational studies.

OBJECTIVES: The hybrid ablation via transdiaphragmatic approach (convergent procedure) is a newly emerging treatment for atrial fibrillation. However, the results reported by different centres are controversial. The purpose of this study is to investigate the efficacy and safety of the convergent procedure by performing a meta-analysis. METHODS: We searched the PubMed, EMBASE and Cochrane Library databases and calculated the pooled estimates. The I2 test, χ2 test and meta-regression analysis were performed to evaluate the heterogeneity. Funnel plots were used to detect publication bias. Trim-and-fill method was performed to identify possible asymmetry. RESULTS: In total, 6 observational studies involving 478 patients were identified for the final analysis. The pooled estimated rate of sinus rhythm maintenance within 12 months was 84.3% (χ2 = 14.69, P = 0.012). The meta-regression analysis showed that the mean duration of atrial fibrillation affected the heterogeneity. Two additional studies need to be trimmed according to the trim-and-fill method. The pooled estimate was 60.2% after filling. The overall complication rate was 9.0%, and the mortality rate was 1.7%. CONCLUSIONS: The efficacy of the convergent atrial fibrillation procedure is relatively satisfactory. However, the overall complication incidence is relatively high, and the procedural mortality rate is unacceptable.

The characteristics of a porcine mitral regurgitation model.

The porcine mitral regurgitation (MR) model is a common cardiovascular animal model. Standardized manufacturing processes can improve the uniformity and success rate of the model, and systematic research can evaluate its potential use. In this study, 17 pigs were divided into an experimental group (n=11) and a control group (n=6). We used a homemade retractor to cut the mitral chordae via the left atrial appendage to establish a model of MR; the control group underwent a sham surgery. The model animals were followed for 30 months after the surgery. Enlargement and fibrosis of the left atrium were significant in the experimental group compared with those in the control group, and left atrial systolic function decreased significantly. In addition, model animals showed preserved left ventricular systolic function. There were no differences in left atrial potential or left ventricular myocardial fibrosis between the two groups. Atrial fibrillation susceptibility in the experimental group was higher than that in the control group. Our method enables the simple and effective production of a MR model with severe reflux that can be used for pathophysiological studies of MR, as well as for the development of preclinical surgical instruments and their evaluation. This model could also be used to study atrial fibrillation and myocardial fibrosis but is not suitable for studies of heart failure.

A comparative study of the characterization of miR-155 in knockout mice.

miR-155 is one of the most important miRNAs and plays a very important role in numerous biological processes. However, few studies have characterized this miRNA in mice under normal physiological conditions. We aimed to characterize miR-155 in vivo by using a comparative analysis. In our study, we compared miR-155 knockout (KO) mice with C57BL/6 wild type (WT) mice in order to characterize miR-155 in mice under normal physiological conditions using many evaluation methods, including a reproductive performance analysis, growth curve, ultrasonic estimation, haematological examination, and histopathological analysis. These analyses showed no significant differences between groups in the main evaluation indices. The growth and development were nearly normal for all mice and did not differ between the control and model groups. Using a comparative analysis and a summary of related studies published in recent years, we found that miR-155 was not essential for normal physiological processes in 8-week-old mice. miR-155 deficiency did not affect the development and growth of naturally ageing mice during the 42 days after birth. Thus, studying the complex biological functions of miR-155 requires the further use of KO mouse models.

miR-155 regulates high glucose-induced cardiac fibrosis via the TGF-ß signaling pathway.

Cardiac fibrosis, as a pathological process, plays an important role in various cardiac diseases. microRNA-155 (miR-155) is one of the most important miRNAs, and previous studies have shown that it is a regulatory factor in various fibrotic diseases. However, the mechanism by which miR-155 affects myocardial fibrosis remains unclear. In this study, we aim to establish the biological function of miR-155 in myocardial fibrosis induced by diabetes in mice. We used normal C57BL/6 wild type (WT) and miR-155 knockout (KO) mice to establish the diabetic model by intraperitoneal injection of streptozotocin, and we utilized echocardiography to evaluate the cardiac function at 30 and 60 days post-modeling. Hematoxylin-eosin (HE) and sirius-red (SR) staining were used to evaluate the degree of myocardial lesions. Furthermore, we extracted cardiac fibroblasts (CFs) from the WT mice and transfected them with miR-155 inhibitors, mimics and negative control siRNAs to analyze the specific mechanism involved in the development of myocardial fibrosis. The results showed that miR-155 deficiency could prevent cardiac fibrosis induced by diabetes in mice and also that attenuated collagen synthesis is induced by high glucose (HG) in CFs. We found that miR-155 regulated cardiac fibrosis via the TGF-ß1-Smad 2 signaling pathway. These findings suggest that miR-155 may be a therapeutic target for preventing cardiac fibrosis induced by diabetes.