Interdigitated impedimetric-based Maackia amurensis lectin biosensor for prostate cancer biomarker.

Highly specific detection of tumor-associated biomarkers remains a challenge in the diagnosis of prostate cancer. In this research, Maackia amurensis (MAA) was used as a recognition element in the functionalization of an electrochemical impedance-spectroscopy biosensor without a label to identify cancer-associated aberrant glycosylation prostate-specific antigen (PSA). The lectin was immobilized on gold-interdigitated microelectrodes. Furthermore, the biosensor's impedance response was used to assess the establishment of a complex binding between MAA and PSA-containing glycans. With a small sample volume, the functionalized interdigitated impedimetric-based (IIB) biosensor exhibited high sensitivity, rapid response, and repeatability. PSA glycoprotein detection was performed by measuring electron transfer resistance values within a concentration range 0.01-100 ng/mL, with a detection limit of 3.574 pg/mL. In this study, the ability of MAA to preferentially recognize α2,3-linked sialic acid in serum PSA was proven, suggesting a potential platform for the development of lectin-based, miniaturized, and cost effective IIB biosensors for future disease detection.

Concerns and perceived obstacles for females with regards to cardiac surgery residency-A survey.

BACKGROUND: A major difference exists between the rate of females and males entering cardiac surgery (CSx) residency in Canada. The objective of this study was to investigate the concerns and perceived obstacles of medical students with regards to CSx residency training to identify potential modifiable factors. METHODS: A 15-question web-based survey was designed to compare male to female medical students' perceptions with regards to CSx training. The survey was distributed to all 682 medical students at Western University (London, ON, Canada) enrolled during 2018 to 2019 academic year. A total of 153 students (63 males vs 90 females) completed the survey. RESULTS: More females perceived significant levels of difficulties to getting accepted in CSx residency programs (44/63 [63.8%] males vs 77/90 [85.6%] females, P = .03). As for their perception of the most difficult aspect about a career in CSx, more males expressed significant concerns about finding a job after completing the residency training (16/63 [25.3%] males vs 10/90 [11.0%] females, P = .02). A similar proportion of students expressed a strong interest in applying to a CSx residency (12/63 [19.0%] males vs 15/90 [16.7%] females, P = .83). Of these, more males expressed concerns about maintaining a work-life balance (6/12 [50%] males vs 1/15 [6.67%] female, P = .02), and more females expressed fears of not getting matched to CSx residency (3/12 [25%] males vs 11/15 [73.3%] females, P = .02). CONCLUSION: Despite showing a strong interest in completing a residency in CSx, female medical students perceive a significant fear of not getting matched to the speciality, which limits them from applying.

FEM Modeling of the Temperature Influence on the Performance of SAW Sensors Operating at GigaHertz Frequency Range and at High Temperature Up to 500 °C.

In this work, we present a two-dimensional Finite Element Method (2D-FEM) model implemented on a commercial software, COMSOL Multiphysics, that is used to predict the high temperature behavior of surface acoustic wave sensors based on layered structures. The model was validated by using a comparative study between experimental and simulated results. Here, surface acoustic wave (SAW) sensors consist in one-port synchronous resonators, based on the Pt/AlN/Sapphire structure and operating in the 2.45-GHz Industrial, scientific and medical (ISM) band. Experimental characterizations were carried out using a specific probe station that can perform calibrated measurements from room temperature to 500 °C. In our model, we consider a pre-validated set of physical constants of AlN and Sapphire and we take into account the existence of propagation losses in the studied structure. Our results show a very good agreement between the simulation and experiments in the full range of investigated temperatures, and for all key parameters of the SAW sensor such as insertion losses, resonance frequency, electromechanical factor of the structure (k2) and quality factor (Q). Our study shows that k2 increases with the temperature, while Q decreases. The resonance frequency variation with temperature shows a good linearity, which is very useful for temperature sensing applications. The measured value of the temperature coefficient of frequency (TCF) is equal to -38.6 ppm/°C, which is consistent with the numerical predictions.

Epitaxial Growth of Sc0.09Al0.91N and Sc0.18Al0.82N Thin Films on Sapphire Substrates by Magnetron Sputtering for Surface Acoustic Waves Applications.

Scandium aluminum nitride (ScxAl1-xN) films are currently intensively studied for surface acoustic waves (SAW) filters and sensors applications, because of the excellent tradeoff they present between high SAW velocity, large piezoelectric properties and wide bandgap for the intermediate compositions with an Sc content between 10 and 20%. In this paper, the growth of Sc0.09Al0.91N and Sc0.18Al0.82N films on sapphire substrates by sputtering method is investigated. The plasma parameters were optimized, according to the film composition, in order to obtain highly-oriented films. X-ray diffraction rocking-curve measurements show a full width at half maximum below 1.5°. Moreover, high-resolution transmission electron microscopy investigations reveal the epitaxial nature of the growth. Electrical characterizations of the Sc0.09Al0.91N/sapphire-based SAW devices show three identified modes. Numerical investigations demonstrate that the intermediate compositions between 10 and 20% of scandium allow for the achievement of SAW devices with an electromechanical coupling coefficient up to 2%, provided the film is combined with electrodes constituted by a metal with a high density.

Left ventricular remodeling after mini-mitral repair-does the complexity of mitral disease matter?

OBJECTIVES: Degenerative mitral valve (MV) regurgitation (MR) is associated with left ventricular (LV) dilatation. Surgical treatment of MR has been shown to favorably affect LV remodeling. We prospectively compared the long-term echocardiographic outcomes of LV remodeling following mini-mitral repair for simple versus complex MV disease. METHODS: We prospectively followed up 203 consecutive patients who underwent mini-MV repair for severe degenerative MR over a 9-year period. Simple disease (n = 122 patients: posterior leaflet prolapse) was compared to complex disease (n = 81 patients: anterior, bilateral or commissural prolapse). Baseline demographics were similar between simple and complex groups (age: 63 ± 13 years vs 60 ± 15 years; p = .2; sex: 71% male vs 72% male, p = 1; preoperative MR grade ≥ 3+: 100%; n = 122; vs 100%; n = 81; p = 1), respectively. RESULTS: Preoperative left ventricular ejection fraction (LVEF) was significantly lower in the complex group as compared to the simple group (57.2% simple vs 56.0% complex; p = .04). Preoperative LV end-systolic diameter (LVESD: 35 mm simple vs 36 mm complex, p < .05) and LV end-diastolic diameter (LVEDD: 50 mm simple vs 51 mm complex; p < .05), as well as LV mass index (99.5 g/m2 vs 102.4 g/m2 ; p = .06) were larger in the complex group. Despite different baseline characteristics of LV function and geometry, both groups had similar remodeling of LV after MV repair. CONCLUSIONS: Patients with complex MV disease are referred late for surgical repair, causing LV function and dimensions to never fully recover. This suggests that earlier referral (before LV changes and potentially before symptoms) may be the preferred approach in those with complex disease.

Update on revascularization in patients with heart failure and coronary artery disease.

PURPOSE OF REVIEW: The review explores the recent findings surrounding the evaluation and the treatment of patients with heart failure and coronary artery disease. It also shed the light on the gaps in this area. RECENT FINDINGS: Surgical revascularization in patients with ischemic cardiomyopathy has the potential to offer symptomatic and survival benefits. SUMMARY: Patients with heart failure and coronary artery disease should be considered candidates for revascularization on the basis of their symptoms, extent of the disease, and comorbidities. Surgical revascularization in these patients provides a symptomatic relief, and a survival benefit.

Aortic dissection following heart transplantation.

A 75-year-old male with a previous orthotopic heart transplantation performed 28 years ago was incidentally discovered to have an asymptomatic chronic type A aortic dissection. Catheter-induced dissection during coronary angiography was believed to be the culprit factor. Aortic root replacement and aortic valve reconstruction were successfully performed.

Thrombolysis of prosthetic mitral valve thrombosis in an infant.

A 7-week-old female developed thrombosis of a mechanical mitral valve and was successfully treated with recombinant tissue plasminogen activator (rt-PA). The management of infants with thrombosed mechanical prosthesis is reviewed.

BAG2 Gene-mediated Regulation of PINK1 Protein Is Critical for Mitochondrial Translocation of PARKIN and Neuronal Survival.

Emerging evidence has demonstrated a growing genetic component in Parkinson disease (PD). For instance, loss-of-function mutations in PINK1 or PARKIN can cause autosomal recessive PD. Recently, PINK1 and PARKIN have been implicated in the same signaling pathway to regulate mitochondrial clearance through recruitment of PARKIN by stabilization of PINK1 on the outer membrane of depolarized mitochondria. The precise mechanisms that govern this process remain enigmatic. In this study, we identify Bcl2-associated athanogene 2 (BAG2) as a factor that promotes mitophagy. BAG2 inhibits PINK1 degradation by blocking the ubiquitination pathway. Stabilization of PINK1 by BAG2 triggers PARKIN-mediated mitophagy and protects neurons against 1-methyl-4-phenylpyridinium-induced oxidative stress in an in vitro cell model of PD. Collectively, our findings support the notion that BAG2 is an upstream regulator of the PINK1/PARKIN signaling pathway.

Metastatic pattern of invasive lobular carcinoma of the breast-Emphasis on gastric metastases.

BACKGROUND AND OBJECTIVES: Breast invasive ductal carcinoma (IDC) and invasive lobular carcinoma (ILC) have different metastatic patterns, but the exact pattern of metastases from ILC is poorly known. This study aimed to determine the frequency of ILC metastases in atypical locations, with an emphasis on gastric metastases. METHODS: Patients with ILC treated at the Saint-Sacrement Hospital (Quebec City, Canada) and the Maisonneuve-Rosemont Hospital (Montreal, Canada) between January 2003 and December 2009 were retrospectively reviewed. Demographic, clinical, and follow-up data were retrieved from the medical charts. Metastases that were diagnosed during follow-up were recorded. RESULTS: Among the 481 patients with ILC, 74 (15.4%) were diagnosed with metastases after a median follow-up of 46 months. Among these 74 patients, 41.9% had metastases in atypical sites. Five patients were diagnosed with histologically confirmed gastric metastases of ILC. CONCLUSION: Metastases of breast ILC to atypical sites might be more frequent than previously reported. Clinicians should keep a high level of suspicion when a patient with a history of ILC develops digestive symptoms. It is important to differentiate metastases from a primary GI tumor by using immunohistochemical markers. J. Surg. Oncol. 2016;114:543-547. © 2016 Wiley Periodicals, Inc.

Mitral valve replacement in young patients: review and current challenges.

Mitral valve repair is the ideal intervention for mitral valve disease with excellent long-term survival comparable to the age-matched general population. When the mitral valve is not repairable, mechanical prostheses may be associated with improved survival as compared with biological prostheses. Newer mechanical and biological valve prostheses have the potential to improve outcomes following mitral valve replacement in young patients. Patients presenting for mitral valve surgery after failed transcatheter mitral valve-in-valve have high rates of postoperative mortality and morbidity, exceeding those seen with reoperative mitral valve surgery, which poses issues in young patients who have a higher cumulative incidence of reintervention.

Patients presenting with mitral valve disease, the most common type of heart valve disease, have a survival advantage when they undergo mitral valve repair as opposed to replacement, and this is particularly true for young patients. When the mitral valve is not repairable, mechanical prostheses (prosthetic implants) may be associated with improved survival as compared with biological prostheses, and this difference is mostly observed until the age of 70 years. Newer techniques of treating mitral valve disease without requiring open heart surgery have not yet been shown to be superior or even equivalent to traditional open heart surgery in the general population. Patients presenting for mitral valve surgery after failure of these newer techniques have high rates of death, exceeding those seen with mitral valve reoperation, which has important implications for young patients with mitral valve disease.

Outcomes of Total Aortic Arch Replacement in a Canadian Nationwide Registry.

BACKGROUND: Accurate benchmarking of outcomes after elective open total arch replacement is important for surgical decision making and for comparisons with emerging endovascular technologies. METHODS: A multicentre registry of consecutive aortic arch procedures in 9 centres across Canada contained 250 elective total arch replacements from 2010 to 2021. A total of 728 patients undergoing elective hemiarch replacement over the same time period was used as a comparator group. Propensity score matching was used to construct 202 well matched pairs. RESULTS: Patients undergoing total arch replacement were 63.2 ± 13.6 years old, and 34% were female. These patients were more likely to have connective tissue disorders compared with patients undergoing hemiarch replacement. When under hypothermic circulatory arrest, the total arch group uniformly used antegrade cerebral perfusion with median nadir temperature of 24°C (interquartile range [IQR] 21-25°C), and median duration 33 minutes (IQR 23-51 minutes). Before matching, in-hospital mortality and stroke rates were 5.2% and 10%, respectively, for the total arch group. After matching, the total arch group had in-hospital mortality similar to the hemiarch group (P = 0.58). Rates of stroke were also not statistically different (P = 0.11). The total arch group was more likely to experience delirium, prolonged intubation, increased intensive care unit length of stay, and transfusions. CONCLUSIONS: Elective total arch replacement is performed with good in-hospital mortality rates that are similar to rates after elective hemiarch repairs. However, total arch replacement was associated with significantly higher rates of other morbidities, including delirium and prolonged intubation.

Hematocrit and Renal Failure in Aortic Arch Surgery: A Society of Thoracic Surgeons Database Study.

BACKGROUND: We examined the association between cardiopulmonary bypass (CPB) hematocrit and postoperative acute renal failure (ARF) in patients undergoing aortic arch surgery with hypothermic circulatory arrest. METHODS: The Society of Thoracic Surgeons Adult Cardiac Surgery Database was queried from 2011-2019 for patients undergoing aortic arch surgery with hypothermic circulatory arrest. A multivariable logistic regression model estimated the adjusted odds of postoperative ARF based on CPB hematocrit. Effects were stratified by preoperative kidney function and duration of hypothermic circulatory arrest using interaction terms. We also investigated the association between postoperative ARF and major postoperative outcomes using multivariable regression models. RESULTS: On adjusted analysis, higher CPB hematocrit (>20-25%, >25-30%, >30%) was associated with lower odds of ARF as compared to lower CPB hematocrit (≤20%) [>20-25%: aOR=0.78(0.65-0.93), p=0.006, >25-30%: aOR=0.65(0.50-0.84), p=0.0007, >30%: aOR=0.45(0.28-0.72), p=0.0008]. The predicted probability of postoperative ARF by CPB hematocrit was higher in patients with lower preoperative renal function (<60 mL/min/1.73m2) (interaction p=0.03). The association between hematocrit and postoperative ARF was not significantly modified by hypothermic circulatory arrest time (interaction p= 0.74). All postoperative outcomes were significantly worse in patients with postoperative ARF (all p<0.0001). CONCLUSIONS: Among patients undergoing aortic arch surgery, a higher CPB hematocrit level is associated with reduced likelihood of postoperative ARF. Preoperative renal function, but not hypothermic circulatory arrest duration, significantly modified this association. The maintenance of higher CPB hematocrit may reduce the incidence of postoperative ARF, especially for patients with poor preoperative renal function.

Induction immunosuppression and post-transplant diabetes mellitus: a propensity-matched cohort study.

Introduction: Post-transplant diabetes mellitus (PTDM) is a common complication among cardiac transplant recipients, causing diabetes-related complications and death. While certain maintenance immunosuppressive drugs increase PTDM risk, it is unclear whether induction immunosuppression can do the same. Therefore, we evaluated whether induction immunosuppression with IL-2 receptor antagonists, polyclonal anti-lymphocyte antibodies, or Alemtuzumab given in the peri-transplant period is associated with PTDM. Methods: We used the Scientific Registry of Transplant Recipients database to conduct a cohort study of US adults who received cardiac transplants between January 2008-December 2018. We excluded patients with prior or multiple organ transplants and those with a history of diabetes, resulting in 17,142 recipients. We created propensity-matched cohorts (n=7,412) using predictors of induction immunosuppression and examined the association between post-transplant diabetes and induction immunosuppression by estimating hazard ratios using Cox proportional-hazards models. Results: In the propensity-matched cohort, the average age was 52.5 (SD=13.2) years, 28.7% were female and 3,706 received induction immunosuppression. There were 867 incident cases of PTDM during 26,710 person-years of follow-up (32.5 cases/1,000 person-years). There was no association between induction immunosuppression and post-transplant diabetes (Hazard Ratio= 1.04, 95% confidence interval 0.91 - 1.19). Similarly, no associations were observed for each class of induction immunosuppression agents and post-transplant diabetes. Conclusion: The use of contemporary induction immunosuppression in cardiac transplant patients was not associated with post-transplant diabetes.

Kaplan-Meier Survival, Actuarial Survival, Censoring, and Competing Events-What Is What?

Survival analyses, most commonly Kaplan-Meier curves, are frequently used in the field of cardiovascular medicine to analyze and graphically illustrate the differences in outcomes between 2 or multiple study groups in randomized controlled trials. Whereas Kaplan-Meier curves provide a nice representation of the survival (or the occurrence of other events of interest) of 1 or several groups of patients, they are commonly misused, especially in the setting of interval censoring, actuarial survival, and competing events. Here, we sought to provide the reader with a simple example that clarifies some of these concepts.

Coaptation length predicts early- and intermediate-term durability following degenerative mitral repair.

OBJECTIVES: The impact of coaptation length on recurrent mitral regurgitation following degenerative mitral repair is not fully understood. METHODS: Between May 2008 and February 2021, 386 consecutive patients underwent mitral repair for degenerative mitral regurgitation at a single centre. We compared patients with a post-repair coaptation length >11 mm (long-coaptation group, n = 230) and ≤11 mm (short-coaptation group, n = 156). The coaptation length cutoff was selected based on published postoperative transesophageal echocardiographic measurement of mitral repair patients and healthy controls. Propensity score with inverse probability of treatment weighting (IPTW) analyses were performed. The median duration of clinical follow-up was 41 months and follow-up was complete in the entire cohort. RESULTS: The long-coaptation patients underwent more neochord implantation (89% vs 65%, P < 0.001) and less leaflet resection (11% vs 29%, P < 0.001). Overall in-hospital/30-day mortality and mitral reintervention occurred in 3 (1%) and 4 (1%) patients, respectively, and freedom from recurrent mitral regurgitation was 98% at 1 year and 94% at 5 years. Freedom from recurrent mitral regurgitation moderate or greater was significantly higher in the long-coaptation patients (IPTW-adjusted difference in average time to recurrent mitral regurgitation: 31 months, 95% confidence interval 9-53, P = 0.006). However, there was no difference in intermediate-term survival between both groups (IPTW-adjusted difference in average time to death: 9.5 months, 95% confidence interval -27 to 46, P = 0.61). Stratified analysis and pairwise comparison of different coaptation intervals also appeared to support the protective effect of longer coaptation on repair durability. CONCLUSIONS: Longer coaptation length appears to be associated with improved intermediate-term durability after mitral repair.

Aortic-Valve Sparing Repair and Homograft and Dacron Pulmonary Reconstruction Long-term After Arterial Switch Operation.

The arterial switch operation is the gold-standard treatment for dextro-transposition of the great arteries. Long-term follow-up data are beginning to reveal its natural history and associated late complications, including various reoperations for those complications. Given the unique anatomy and the increasing longevity of these patients, there is a need for effective surgical repair options to address aneurysmal and degenerative changes in both neoaortic and pulmonic roots. Thereby, we describe our technique and the novel considerations for prosthetic choice with reconstruction of both the neoaortic root and pulmonary artery, with satisfactory postoperative results.

La détransposition artérielle constitue le traitement de référence dans les cas de dextro-transposition des gros vaisseaux. De nouvelles données, issues du suivi à long terme, nous permettent de mieux comprendre l'évolution naturelle à la suite de cette intervention et les complications tardives qui y sont associées, y compris les diverses interventions à réaliser pour les corriger. Étant donné les caractéristiques anatomiques uniques de ces patients et l'augmentation de leur espérance de vie, il est nécessaire de proposer des options efficaces de réparations chirurgicales pour remédier aux changements anévrismaux et dégénératifs des racines néoaortique et pulmonaire. Ainsi, nous décrivons la technique que nous avons utilisée et les nouveaux éléments qui entrent en ligne de compte dans le choix d'une prothèse pour une reconstruction de la racine néoaortique et de l'artère pulmonaire, avec des résultats postopératoires jugés satisfaisants.