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Seed recruitment is a major driver of mangrove restoration globally. It is hypothesized that soil condition and channel hydrology can accelerate seedling recruitment and regeneration after a major disturbance. Species abundance, diversity indices, microbial and chemical concentrations in sand-filled mangrove forest was studied. Eight plots (area = 3902.16 m2) were established with ten transects in each plot in a random block design to investigate the effect of soil conditions on seedling growth. A total of 1, 886 seedlings were physically counted. Seedling abundance was significantly different between red (Rizophora racemosa), white (Laguncularia racemosa) and black (Avicennia germinans) mangroves and nypa palm (nypa fruticans). The most dominant species was black mangroves and the least dominant species was nypa palm. Muddy soils had the most abundant species while sandy soils had the least abundant species. Furthermore, semi-muddy soils had the highest species diversity (H = 0.948) whereas muddy soils had the least species diversity (H = 0.022). The soil metal concentration has no correlation with seed abundance and occur in the order Iron>Nitrate>Copper>Cadmium. Soil with high species diversity had high soil microbial population; however, seedling abundance was correlated with soil nutrients and not heavy metals. Small seeds are easily recruited while good soil condition plus existing hydrological connection facilitated natural seedling regeneration in the disturbed mangrove forest.

Rina Sha

and 3 more

Background: Although epicardial adipose tissue (EAT) has been proved be associated with atrial fibrillation (AF) and post-ablation AF recurrence, the relationship between EAT and AF after cardiac surgery (AFACS) is not evident, yet. Objective: In the study, we aim to perform a systematic review and meta-analysis to assess the association between EAT and AFACS and whether it is independent of the measurement methods. Methods: Systematic reach was implemented until May, 30, 2020, which “atrial fibrillation” and “epicardial adipose tissue” were as the main items in electronic databases. Analysis was stratified by EAT measurement methods into three pooled meta-analyses on 1) total EAT volume, 2) left atrium (LA)-EAT volume and 3) EAT thickness between two groups with and without AFACS, estimating standardized mean difference (SMD) with a random effect model. Results: Eight articles with ten studies (546 patients) were included. Accordingly, the results of meta-analysis showed that EAT was higher in AFACS subjects, regardless of the methods of EAT measurement.[ total EAT volume: SMD = 0.56 ml; 95% confidence interval (CI) = 0.56-1.10ml, I2 = 0.90, P=0.04; EAT thickness: SMD = 0.85mm; 95% CI = 0.04-1.65mm, I2 = 0.90, P=0.04; LA-EAT volume: SMD = 0.57ml, 95% CI = 0.23-0.92ml, I2 = 0.00, P=0.001.] And there was no evidence of publication bias. Conclusion: EAT may be a potential marker and therapeutic target for AFACS. However, larger scale studies are still required, and evaluation is needed to for further estimation.

Maryam Tashvighi

and 11 more

Barbara Filosa

and 2 more

Title: Intratympanic gentamicin injection in Ménière’s disease: our twelve years’ experience and outcomes. Objective: The aim of our study is to evaluate the effectiveness of intratympanic gentamicin injection(ITG) on vertigo control with reduced doses and its hearing effects. Study design: Retrospective study Materials and Method: The study was conducted at our Otolaryngology Department of AORN “S.G. Moscati” between January 2005 and January 2015 on 72 patients with disabling unilateral Meniere’s disease treated with ITG. We use 0.2-0.3 mL of gentamicin sulfate at a concentration of 40mg/ml, injected into the affected ear through the posterior-inferior quadrant of the tympanic membrane. The procedure was carried out for three following days. Main outcome measures: vertigo control and hearing threshold changes after ITG treatment. Results: In the 98.6% of the patients (n=71) the ITG produced the full remission of the vertiginous symptoms. In the 91.6% of cases(n=66) a single treatment (three consequent injections) was sufficient to control vertigo, in the 5.5% of cases (n=4) two treatments were necessary to control vertigo and in the 1.3% of patients(n=1) three treatments were necessary to control vertigo. In no case we have had hearing loss after ITG procedure. The pre-treatment pure tone average was 48 db. The post-treatment pure tone average was 49.2 db. This difference was no statistical difference. Conclusion: In this study we reported high vertigo control, long follow-up and no case of significant hearing worsening. We consider the three injections in the following three days with low doses of gentamicin a safe and valid treatment for Meniere’s disease. Keyword : Meniere’s disease, intratympanic gentamicin injection, vertigo control, hearing worsening, aminoglycoside ototoxicity.

Xiang-Fei Feng

and 7 more

Introduction: Cardiac resynchronization therapy via biventricular pacing is an established therapy for patients with heart failure. However, high nonresponder rates and inability to predict response remains a challenge. Recently left bundle branch area pacing (LBBAP) has been shown to be feasible and may also improve clinical outcomes. In this article we describe sequential LBBAP followed by left ventricular (LV) pacing (LOT-CRT) and assess the feasibility of LOT-CRT. Methods: The RV implantation site was positioned and the LBBAP lead was implanted using our methods. The QRS duration (QRSd) at baseline, during LBBAP, biventricular pacing, and LOT-CRT was measured. Results: LOT-CRT was successful in 5 patients (age 71.8 ± 5.1 years, men 3, ischemic 3). The QRSd at baseline was 158.0 ± 13.0 ms and significantly narrowed to 117.0 ± 6.7 ms during LOT-CRT (P < 0.01). During 3-month follow-up, LV ejection fraction improved from 32.8 ± 5.2 % to 45.0 ± 5.1% (P < 0.01), and New York Heart Association functional class changed from 3.25 ± 0.5 to 2.5 ± 0.6 (P < 0.05). A decrease in left ventricular end-diastolic dimension was observed, with widening from (68.2 ± 12.3) mm at baseline to (62.2 ± 11.3) mm at pacing (P < 0.05). The length of operation time was (152.0 ± 31.1) min. Conclusions: The study demonstrates that LOT-CRT is clinically feasible in patients with systolic HF and LBBB. LOT-CRT was associated with significant narrowing of QRSd and improvement in LV function, especially in patients with ischemic cardiomyopathy.

Rakesh Saroj

and 2 more

Objective The main objective of this paper is to compare the performance of logistic regression and decision tree classification methods and to find the significant environment determinants that causes pre-term birth. Design, setting and population Between 2017 to 2018, 90 pregnant females underwent birth outcome followed by research staff at our institutions, out of those 50 are full-term and 40 are preterm births in this study. Method Before and after feature selection logistic regression and decision tree classifier model has been compared in this dataset and to evaluate the model accuracy. Main outcome measures Preforming the accuracy of machine learning classification model and important factors on pre-term birth. Results: Using chi-square test and find the Area of residence and GSH, MDA, α-HCH, total HCH and total DDT are responsible for the preterm birth. Using the multiple logistic regression, pre term birth was associated with MDA and α-HCH (95% CI 0.04 to 0.48 and 95% CI 0.82 to 0.97). The logistic and decision tree model comparison result shows that logistic regression is better in terms of metrics (precision = 0.92, F1-score = 0.96 and AUROC = 0.97), while decision tree performs the poor (precision = 0.75, F1-score = 0.86 and AUROC = 0.87). Conclusions The logistic regression is accurate model to predict the pre-term as compare to decision tree method. The variables like α-HCH , total HCH and MDA (Malondialdehyde) are the most influential factors for preterm birth.

Marielle Meurice

and 4 more

Objective: Evaluate satisfaction and experience with telemedicine and home use of mifepristone and misoprostol for abortion to 10 weeks’ gestation. Design: Cross-sectional evaluation. Setting: British Pregnancy Advisory Service (BPAS) clinics in England and Wales. Population: 1,144 clients who used mifepristone and misoprostol at home from 11 May to 10 July 2020. Methods: We sent a text message with a link to a web-survey 2-3 weeks after treatment. Questions evaluated satisfaction and experiences, including telephone consultations and provision of medicines by post or collection from clinic. We used bivariate and multivariate regression to explore associations between client characteristics and outcomes. Main Outcome Measures: Overall satisfaction (5-point Likert scale) and reported contact with a healthcare provider (HCP). Results: Respondents primarily described home use of medications as ‘straightforward’ (75.8%) and most were ‘very satisfied’ (78.3%) or ‘satisfied’ (18.6%) with their overall experience. Being ‘very satisfied’ was associated with parity (aOR 1.53, 95% CI 1.09-2.14) and pain control satisfaction (aOR 2.22, 95% CI 1.44-3.44). HCP contact was reported by 14.7%; mainly to BPAS’ telephone aftercare service (76.8%). Dissatisfaction with pain control (aOR 3.62 95% CI 1.79-7.29) and waiting >1 week to use mifepristone (aOR3.71, 95% CI 1.48-9.28) were associated with HCP contact. If needed in future, most (77.8%) would prefer home use of mifepristone and misoprostol and pills by post (68.9%). Conclusions: Satisfaction with home use of mifepristone and misoprostol is high. Most clients do not need HCP support during or after home use, but aftercare should be available.

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Oktay Ucer

and 3 more

The sinoatrial node in medication-resistant inappropriate sinus tachycardia: to modify or to ablate?Khalil El Gharib1*1Hôtel-Dieu de France, Beirut, Lebanon*Author for correspondence: khalil.gharib@outlook.comKEYWORDS: IST, sinus node modification, sinus node ablation, radiofrequency ablation, surgical ablationNo conflict of interest to discloseFunding: noneInappropriate sinus tachycardia (IST) is defined as a resting heart rate >100 beats per minute (with a mean heart rate >90 beats per minute over 24 hours) associated with highly symptomatic palpitations(1). The syndrome is associated neither with structural heart disease nor with any secondary cause of sinus tachycardia(2) and evidence suggests that enhanced intrinsic automaticity of the sinoatrial node, which can be due to anti-β-adrenergic antibodies, is behind its genesis(3). However, it is benign in terms of clinical outcomes and echocardiographic evidence of ventricular dysfunction(4), being rarely associated with tachycardia-induced cardiomyopathy(3).Patients with IST are essentially treated with ß-blockers to alleviate their symptoms(5). Ivabradine, a drug that inhibits funny calcium channels, particularly abundant in the SA node, showed modest benefit, receiving class IIa recommen­dation in the treatment of IST(4). But, the duration of medical therapy might be indefinite, and, a considerable number of patients would respond inadequately, or have no response, even after prolonged therapy(5). Historically, such patients would have subtotal right atrial excision, atrioventricular junctional ablation with permanent pacemaker implantation, or chemical occlusion of the sinus node artery(6). These options are considered today unacceptable in this setting, and other therapeutic approaches should be unveiled when resistance to medical treatment appears.Electrophysiological study was initially purely diagnostic, but recent advances in technology have allowed us to intervene(7); patients with ventricular and supraventricular tachyarrhythmias are successfully treated with percutaneous catheter procedures. Of these, SA node ablation/ modification has been proposed as alternative approaches in IST that is not responding to medical treatment; trials reported auspicious results, highlighted here.Electrophysiologic mapping to the site of the earliest endocardial activation during either spontaneous sinus tachycardia or isoproterenol-induced sinus tachycardia has rendered these procedures feasible(8). Additionally, combination with intracardiac echocardiography permitted a more accurate electrophysiologic and anatomic localization of the sinoatrial node(9).Sinus node modification is not a focal ablation, but requires complete abolition of the cranial portion of the SA node complex, the one that exhibits the most of the autonomic activity(9). It is defined as successful when the heart rate decreases by 30 beats per minute (bpm) during isoproterenol infusion(8). Short-term success was also defined by other investigators when there was a reduction of the baseline sinus rate to less than 90 bpm and the sinus rate during isoproterenol infusion by more than 20% or by 25%(8). The acute success rate for modification has been varying between 76 and 100 % across trials, while long-term clinical outcomes are modest at best, with reported freedom from IST ranging from 23 to 85%(10).Complications specific to SA node modification include superior vena cava (SVC) syndrome, diaphragmatic paralysis, and sinus node dysfunction(10). And while modification with conventional methods has its setbacks, modification using laser energy can be considered in the setting of IST. This modality creates clear-cut homogenous transmural lesions of the myocardium that comprises the scattered “functional” SA node(11). The burnt myocardium will then heal into a dense fibrous scar, decreasing potential amplitudes. And when adapting laser energy settings to the thickness of the myocardial wall, collateral dam­ages such as esophageal fistulae, lung burns, and phrenic nerve palsy will be avoided(11); thus, this technique may prove itself as a new intriguing alternative for the safe and effective treatment of IST.SA node modification is apt in achieving acute reductions in postprocedural heart rate. However, and as aforementioned, success rates are suboptimal in terms of symptomatic control with a significant recurrence rate(12). Catheter ablation aiming at either total exclusion and obliteration of the SA node has been described and performed, success being defined as a slowing of >50% from the baseline rate of tachycardia along with a junctional escape rhythm(12). With radiofrequency (RF) applications, the earliest local atrial activation time would shift from a cranial location to a more caudal one, usually at the mid-lateral right atrium(5). Reviews have reported that acute success rates were consistently to be as high as 88.9%, with an overall frequency of recurrence of 19.6%, the latter occurring within a wide range of post-ablation intervals, anywhere from a few weeks to several months after the procedure(12). Additionally, Takemoto and colleagues documented a significant drop in B-type natriuretic peptide levels, 6 to 12 months after ablation, suggesting fewer stretching shears on cardiac muscle.Two types of response of the sinus tachycardia to RFA were observed across studies, whether a step-wise reduction in sinus rate accompanying migration of the site of earliest atrial activation in a cranial-caudal direction along the lateral right atrial wall, or an abrupt drop in heart rate in response to RFA at a focal site of earliest atrial activation(13).However, RFA of inappropriate sinus tachycardia requires a large number of applications of radiofrequency energy and is, as in SA node modification, associated with a high recurrence rate(13). Complete remission is achieved only in approximately 50% of patients in some studies(14); longer history of IST and those reporting near syncope/syncope having a higher probability of recurrence(15).While other studies have shown that RF ablation of the SA node can achieve even longer-term reductions in the sinus rate and relief of symptoms in two-thirds of patients with drug-refractory, inappropriate sinus tachycardia(13), aiming specific sites related to the SA node should be elaborated, for better and optimal outcomes Killu and colleagues created a lesion in the arcuate ridge resulting in complete abolition of the tachycardia, since arrhythmias arising in this region may exhibit both electrocardiographic and clinical similarities to IST(16). This has led to consider ablation of the arcuate ridge as a treatment of refractory IST, necessitating larger trials to confirm its potential role.Phrenic nerve injury is a severe and dreaded complication of SN ablation(12). Pericarditis, right diaphragmatic paralysis, and SVC syndrome are other undesirable side effects of the procedures, variously reported in studies. but a common complication was observed in them all, atrial tachyarrhythmias(12). It has been hypothesized that myocardial pathology, such as inflammation and fibrosis, considered iatrogenic due to the ablation procedures, may be promoting arrhythmias both in the region of the SA node, as well as in remote locations(12). Through multivariable analysis, higher resting heart rates post-ablation and smaller cranial-to-caudal shifts have been defined as predictors of atrial arrhythmias(15). In conclusion, catheter ablation could be considered an effective treatment for highly symptomatic, drug-refractory patients, even for those who did not respond to SA node modification(5).The sinus node is located close to the epicardial surface and catheter-based ablations do not always make full-thickness lesions across the atrial muscle, leading to failure of the ablation(17), besides the numerous trabeculae and the widely variable anatomy.Surgical ablation is not a first-line or routine management strategy for IST, but it has been proposed when IST resists or recurs after SN modification/ endocardial ablation(17). Effectively, in several studies, epicardial lesions, through a single small incision in one of the intercostal spaces, successfully slowed heart rate and shifted activation to a more caudal location, and surprisingly, subsequent endocardial lesions led to an even greater drop in heart rate and more caudal site of earliest activation(18). These outcomes were again replicated when using minimally invasive thoracoscopic ablation of the epicardial site of the SA node, concluding of the promising efficacy and the safety of this approach, since it preserves the phrenic nerve(17), although continued follow-up after surgery is required.Medication-resistant IST remains a medical challenge for physicians and cardiologists; and in the era of great advances in interventional cardiology, its treatment remains debatable. Sinus node modification/ ablation is not recommended as first-line therapy in IST, this procedure should be considered only in drug-refractory patients who have severe symptoms(13). Although the number of patients in the available studies is generally small, both procedures have documented an encouraging success rate in the short-term, while being less impressive in the long-term. It has been hypothesized that this discrepancy is due to the relatively large potential area of atrial pacemaker cells(18); modification or ablation may fail to ablate or isolate all the pathways that comprise the functional SA node because they often target the anatomic part and the area of earliest atrial activation(19). Others have explained that the long-term slowing in rhythm fails because these procedures inconsistently produce transmural lesions in the right atrium. Surgical treatment of IST has proposed a solution to the latter conflict when isolating the SA node with a wide cuff of surrounding atrial muscle(19). And with the advent of bipolar RF clamps and minimally invasive cardiac surgical techniques with thoracoscopic guidance, this approach appears more appealing than before, especially when combined with endocardial ablation(19). But again, current data specifies employing these techniques in highly selected cases.


and 10 more

Background: There is insufficient evidence regarding the comparison of Rapid Deployment aortic valve replacement(RDAVR) to TAVR in intermediate-risk patients with severe symptomatic aortic stenosis(AS) Aims: We compare the 2-years outcomes between RDAVR with INTUITY and TAVR with SAPIEN 3 in intermediate-risk patients with AS. Methods: Inclusion criteria: severe AS implanted with RDAVR or TAVR; EUROSCORE II ≥ 4% and clinical evaluation by Heart Team. Regression adjustment for the propensity score was used to compare RDAVR with TAVR(1:1). Primary endpoint: composite criterion of death, disabling stroke or rehospitalization. Secondary endpoints: occurrence of major bleeding post-operative complications, paravalvular regurgitation (PVR)≥2 and patient-prosthesis mismatch(PPM) at 1 month and pacemaker implantation at 2 years. Results: A total of 152 patients were included from 2012 to 2018: 48 in the RDAVR group and 104 in the TAVR group. Mean age was 82.7±6, 51.3% were female, mean Euroscore II was 6.03±1.6% and mean baseline LVEF was 56±13%,mean indexed iEOA was 0.41±0.1cm/m2, mean gradient was 51.7±14.7mmHg. Patients with RDAVR were younger(79.5±6vs82.6±6,p=0.01), at higher risk (EUROSCORE2 6,61±1,8%vs5,63±1,5%, p=0.005), combined surgery was performed in 28 patients(58.3%). Twenty-two patients(45.99%) met the primary outcome in the RDAVR group and 32 patients(66.67%) in the TAVR group. By 1:1propensity score matching analysis, there was a significant difference between both groups in favor of RDAVR(HR=0.58[95%CI:0.34;1.00],p=0.04). No difference were observed in PPM occurrence(0.83;[0.35-1.94];p=0.67),major bleeding events(1.33;[0.47-3.93];p=0.59),PVR≥2(0.33[0-6.28],p=0.46), and pacemaker implantation (0.84[0.25-2.84],p=0.77).Conclusion: RDAVR is associated with better 2-years outcomes than TAVR in intermediate-risk patients with severe symptomatic AS.

Francesca Mori

and 10 more

Marco Moscarelli

and 9 more

Objective: Cardiac tumors are rare conditions. The vast majority of them are benign yet they may lead to serious complications. Complete surgical resection is the gold standard treatment and should be performed as soon as the diagnosis is made. Median sternotomy (MS) is the standard approach and provides excellent early outcomes and durable results at follow-up. However, minimally invasive (MI) is gaining popularity and its role in the treatment of cardiac tumors needs further clarification. Methods: A systematic literature review identified 12 candidate studies; of these, 11 met the meta-analysis criteria. We analyzed outcomes of 653 subjects (294 MI and 359 MS) with random effects modeling. Each study was assessed for heterogeneity. The primary endpoints were mortality at follow-up and tumor relapse. Secondary endpoints included relevant intra- and post-operative outcomes; tumor size was also considered. Results: There were no significant between-group differences in terms of late mortality (incidence rate ratio (IRR): MI vs. MS, 0.98 [95% CI: 0.25¬–3.82], p = 0.98). Few relapses and redo surgery were observed in both groups (IRR: 1.13[0.26-4.88], p=0.87);( IRR: 1.92 [95% CI: 0.39-9.53], p=0.42); MI was associated to prolonged operation time yet with no effects on clinical outcomes. Tumor size did not significantly differ between groups. Conclusions: Both MI and MS are associated with excellent early and late outcomes with acceptable survival rate and low incidence of recurrences. This study confirms that cardiac tumor may be approached safely and radically with a MI approach.

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