Machine learning (ML) is a field in computer science that demonstrated to effectively integrate clinical and imaging data for the creation of prognostic scores. The current study investigated whether ...a ML score, incorporating only the 16 segment coronary tree information derived from coronary computed tomography angiography (CCTA), provides enhanced risk stratification compared with current CCTA based risk scores.
From the multi-center CONFIRM registry, patients were included with complete CCTA risk score information and ≥3 year follow-up for myocardial infarction and death (primary endpoint). Patients with prior coronary artery disease were excluded. Conventional CCTA risk scores (conventional CCTA approach, segment involvement score, duke prognostic index, segment stenosis score, and the Leaman risk score) and a score created using ML were compared for the area under the receiver operating characteristic curve (AUC). Only 16 segment based coronary stenosis (0%, 1–24%, 25–49%, 50–69%, 70–99% and 100%) and composition (calcified, mixed and non-calcified plaque) were provided to the ML model. A boosted ensemble algorithm (extreme gradient boosting; XGBoost) was used and the entire data was randomly split into a training set (80%) and testing set (20%). First, tuned hyperparameters were used to generate a trained model from the training data set (80% of data). Second, the performance of this trained model was independently tested on the unseen test set (20% of data).
In total, 8844 patients (mean age 58.0 ± 11.5 years, 57.7% male) were included. During a mean follow-up time of 4.6 ± 1.5 years, 609 events occurred (6.9%). No CAD was observed in 48.7% (3.5% event), non-obstructive CAD in 31.8% (6.8% event), and obstructive CAD in 19.5% (15.6% event). Discrimination of events as expressed by AUC was significantly better for the ML based approach (0.771) vs the other scores (ranging from 0.685 to 0.701), P < 0.001. Net reclassification improvement analysis showed that the improved risk stratification was the result of down-classification of risk among patients that did not experience events (non-events).
A risk score created by a ML based algorithm, that utilizes standard 16 coronary segment stenosis and composition information derived from detailed CCTA reading, has greater prognostic accuracy than current CCTA integrated risk scores. These findings indicate that a ML based algorithm can improve the integration of CCTA derived plaque information to improve risk stratification.
The protein products of
NLRP3
and
CASP1
genes are involved in the cleavage of pro-IL-1B and pro-IL-18 leading to the active cytokines, which play an important role in the development of the acute ...coronary syndrome (ACS). The aim of the present study was to evaluate whether
NLRP3
and
CASP1
gene polymorphisms are biomarkers of ACS susceptibility in Mexican population. Two polymorphisms of the
CASP1
gene
G+7/in6A
(rs501192) and
A10370-G Exon-6
(rs580253) and one of the
NLRP3
gene
UTR′3 G37562-C
(rs10754558) were genotyped by 5′ exonuclease TaqMan assays in a group of 617 patients with ACS and 609 control individuals. Under recessive model, the
CASP1 G+7/in6A
polymorphism was associated with an increased risk of developing ACS when compared to healthy controls (OR = 1.76, 95% CI 1.08–2.86, P
Res
= 0.022). In the same way, under recessive model, the
CASP1 A10370-G
was associated with increased risk of ACS (OR = 1.75, 95% CI 1.07–2.85, P
Res
= 0.025). Moreover, under co-dominant, dominant, over-dominant, and additive models, the
NLRP3 UTR′3 G37562-C
was associated with a decreased risk of ACS (OR = 0.45, 95%CI 0.22–0.92,
P
Co-dom
= 0.006; OR = 0.61, 95%CI 0.44–0.84,
P
Dom
= 0.002; OR = 0.67, 95%CI 0.48–0.94,
P
Over-dom
= 0.02; and OR = 0.65, 95%CI 0.50–0.94,
P
Add
= 0.02, respectively). In summary, this study demonstrates that the
G+7/in6A
and
A10370-G
polymorphisms of the
CASP1
gene are associated with increased risk of developing ACS, whereas the
UTR′3 G37562-C
polymorphism of the
NLRP3
gene is associated with a decreased risk of developing ACS in Mexican population.
Objective:
The aim of this study was to compare two complex vascular access techniques that utilize the axillary artery as inflow and accesses were created with early cannulation grafts: the ...axillary-atrial arteriovenous graft versus axillary-iliac arteriovenous graft.
Methods:
This is a retrospective study of end-stage renal disease patients with occluded intrathoracic central veins that underwent complex hemodialysis access creation in our institution after failed endovascular recanalization attempts. Patients’ demographics, comorbidities, number and types of previous accesses, intraoperative variables, and clinical outcomes were collected and compared.
Results:
Four patients underwent axillary-atrial arteriovenous graft creation with Flixene™ (Atrium™, Hudson, NH, USA) grafts, through a midline sternotomy to expose the right atrium; all were successfully implanted and used for hemodialysis within the first 72 h; one patient developed a pseudoaneurysm in the mid-graft portion, requiring surgical repair, and it is currently functional. Eight axillary-iliac arteriovenous grafts were created; all grafts were patent and were utilized within 96 h after placement. At 6 months of follow-up period, five (62 %) of our patients underwent graft thrombectomy, one (12 %) balloon angioplasty at the vein anastomosis secondary to stenosis, and two (25 %) grafts were removed due to infectious complications. Axillary-atrial arteriovenous graft and axillary-iliac arteriovenous graft primary patency rates at 6 months were 75% and 48%, respectively; 6-month secondary patency of the axillary-atrial arteriovenous graft compares favorably against that of axillary-iliac arteriovenous graft (100% vs 75%, respectively).
Conclusion:
Despite the invasiveness, direct atrial outflow procedures remain a valid alternative in carefully selected patients with adequate cardiopulmonary reserve.
Inferences based on regression models for a directional response are usually problematic. This paper presents a Bayesian analysis of a regression model for circular data using the projected normal ...distribution. Inferences about the model are based on samples from the posterior densities which are obtained using the Gibbs sampler after the introduction of suitable latent variables. The problem of missing data in the response variable is also addressed in this context as is the use of a predictive criterion for model selection. The procedures are illustrated using two simulated datasets a dataset previously analysed in the literature and a real dataset concerning wind directions.
The 26S proteasome is essential for proteostasis and the regulation of vital processes through ATP-dependent degradation of ubiquitinated substrates. To accomplish the multi-step degradation process, ...the proteasome's regulatory particle, consisting of lid and base subcomplexes, undergoes major conformational changes whose origin is unknown. Investigating the
proteasome, we found that peripheral interactions between the lid subunit Rpn5 and the base AAA+ ATPase ring are important for stabilizing the substrate-engagement-competent state and coordinating the conformational switch to processing states upon substrate engagement. Disrupting these interactions perturbs the conformational equilibrium and interferes with degradation initiation, while later processing steps remain unaffected. Similar defects in early degradation steps are observed when eliminating hydrolysis in the ATPase subunit Rpt6, whose nucleotide state seems to control proteasome conformational transitions. These results provide important insight into interaction networks that coordinate conformational changes with various stages of degradation, and how modulators of conformational equilibria may influence substrate turnover.
Maritime transport is a vital sector for global trade and the world economy. Particularly for islands, there is also an important social dimension of this sector, since island communities strongly ...rely on it for a connection with the mainland and the transportation of goods and passengers. Furthermore, islands are exceptionally vulnerable to climate change, as the rising sea level and extreme events are expected to induce severe impacts. Such hazards are anticipated to also affect the operations of the maritime transport sector by affecting either the port infrastructure or ships en route. The present study is an effort to better comprehend and assess the future risk of maritime transport disruption in six European islands and archipelagos, and it aims at supporting regional to local policy and decision-making. We employ state-of-the-art regional climate datasets and the widely used impact chain approach to identify the different components that might drive such risks. Larger islands (e.g., Corsica, Cyprus and Crete) are found to be more resilient to the impacts of climate change on maritime operations. Our findings also highlight the importance of adopting a low-emission pathway, since this will keep the risk of maritime transport disruption similar to present levels or even slightly decreased for some islands because of an enhanced adaptation capacity and advantageous demographic changes.
Biopolymers are widely used for design sustained drug delivery systems (SDDS) and biomaterials for tissue engineering. Reducing wound infections still constitutes one of the major challenges facing ...the wound care. The aim of this study was to synthetize, characterize and evaluate a single (polymeric spheres) and a binary polymeric biomaterial (polymeric spheres imbedded in a poly(vinyl alcohol) (PVA) scaffold) as a SDDS. Polymeric spheres were prepared by complex coacervation and the binary system of the chitosan (CH) -PVA beads embedded in a PVA scaffold prepared by Ice Segregation Induced Self-Assembly (ISISA) process. Both systems were physicochemically characterized using Fourier Transform Infrared spectroscopy (FTIR), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). In vitro ciprofloxacin (CFX) release kinetics were evaluated simulating physiological conditions under sink conditions. Physicochemical characterization showed interactions between all components forming beads; in contrast, beads-scaffold interactions were not detected making evident the presence of two different phases in the binary system. The CFX release kinetics revealed that both systems were SDDS, simple system release 97.0 ± 6.9% in 7 days, while the binary was 68.56 ± 6.6% during 14 days of evaluation. Binary system emerges as a potential tool for evaluate the long-lasting infection control in the treatment of skin wounds.
Multiple myeloma (MM) is one of the most common malignancies found in hematology.
To describe the features of patients with MM and perform a survival analysis according to the different treatment ...protocols used between 2000 and 2016.
Analysis of the database of the Chilean national anti-neoplastic drug program. Information was obtained from 1,103 patients, with a median age of 64.5 years (range 27-95) and a male to female ratio of 1:1.2.
The mean overall survival (OS) of patients receiving or not receiving Thalidomide was 46 and 30 months, respectively (p < 0.01). The mean OS of patients treated before 2007 (treated with melphalan and prednisone) and between 2007 and 2012 (treated with thalidomide and dexamethasone) was 36 and 48 months respectively. In the group starting in 2013 (treated with cyclophosphamide, thalidomide and dexamethasone) the median survival had not been reached at 20 months of follow up (p = 0.01 for all comparisons). Autologous transplantation (AT) was carried out in only 18% of the eligible patients. The median OS of the patients who receive an AT had not been reached at 48 month compared with 36 month among those who did not received the procedure (p < 0.01).
Even though overall survival has improved with time, new drugs must be introduced in our protocols to obtain similar results to those obtained worldwide.
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