Muscle Mass, Muscle Strength, and Health-Related Quality of Life in Kidney Transplant Recipients: Results of the TransplantLines Biobank and Cohort Study.

Introduction: Muscles are crucial for daily activities, and kidney transplant recipients (KTRs) often have reduced muscle mass and strength. We aimed to investigate the potential relationship of muscle mass and strength with physical health-related quality of life (HRQoL) in KTRs.

Methods: Data from the TransplantLines Biobank and Cohort Studies were used.

Mapping and Removing the Ventricular Far Field Component in Unipolar Atrial Electrograms.

Objective: Unipolar intracardiac electrograms (uEGMs) measured inside the atria during electro-anatomic mapping contain diagnostic information about cardiac excitation and tissue properties. The ventricular far field (VFF) caused by ventricular depolarization compromises these signals. Current signal processing techniques require several seconds of local uEGMs to remove the VFF component and thus prolong the clinical mapping procedure.

Automatic Identification of Reentry Mechanisms and Critical Sites During Atrial Tachycardia by Analyzing Areas of Activity.

Objective: Atrial tachycardia (AT) still poses a major challenge in catheter ablation. Although state-of-the-art electroanatomical mapping systems allow to acquire several thousand intracardiac electrograms (EGMs), algorithms for diagnostic analysis are mainly limited to the amplitude of the signal (voltage map) and the local activation time (LAT map). We applied spatio-temporal analysis of EGM activity to generate maps indicating reentries and diastolic potentials, thus identifying and localizing the driving mechanism of AT.

An adaptive spatio-temporal Gaussian filter for processing cardiac optical mapping data.

Optical mapping is widely used as a tool to investigate cardiac electrophysiology in ex vivo preparations. Digital filtering of fluorescence-optical data is an important requirement for robust subsequent data analysis and still a challenge when processing data acquired from thin mammalian myocardium. Therefore, we propose and investigate the use of an adaptive spatio-temporal Gaussian filter for processing optical mapping signals from these kinds of tissue usually having low signal-to-noise ratio (SNR).

[Colombian Guidelines of clinical practice for the use of immunoglobulins in the treatment of replacement and immunomodulation].

Immunoglobulins are heterodimeric proteins composed of 2 heavy chains and 2 light chains. Human immunoglobulin G (IgG) is a plasma derivative and contains more than 95% of IgG. The composition of IgG subclasses is similar to that of normal human plasma.

Comparison of Baseline Wander Removal Techniques considering the Preservation of ST Changes in the Ischemic ECG: A Simulation Study.

The most important ECG marker for the diagnosis of ischemia or infarction is a change in the ST segment. Baseline wander is a typical artifact that corrupts the recorded ECG and can hinder the correct diagnosis of such diseases. For the purpose of finding the best suited filter for the removal of baseline wander, the ground truth about the ST change prior to the corrupting artifact and the subsequent filtering process is needed.

Electrocardiographic features for the measurement of drivers' mental workload.

This study examines the effect of mental workload on the electrocardiogram (ECG) of participants driving the Lane Change Task (LCT). Different levels of mental workload were induced by a secondary task (n-back task) with three levels of difficulty. Subjective data showed a significant increase of the experienced workload over all three levels.

P wave detection and delineation in the ECG based on the phase free stationary wavelet transform and using intracardiac atrial electrograms as reference.

Robust and exact automatic P wave detection and delineation in the electrocardiogram (ECG) is still an interesting but challenging research topic. The early prognosis of cardiac afflictions such as atrial fibrillation and the response of a patient to a given treatment is believed to improve if the P wave is carefully analyzed during sinus rhythm. Manual annotation of the signals is a tedious and subjective task.

Automatic SVM classification of sudden cardiac death and pump failure death from autonomic and repolarization ECG markers.

Background: Considering the rates of sudden cardiac death (SCD) and pump failure death (PFD) in chronic heart failure (CHF) patients and the cost-effectiveness of their preventing treatments, identification of CHF patients at risk is an important challenge. In this work, we studied the prognostic performance of the combination of an index potentially related to dispersion of repolarization restitution (Δα), an index quantifying T-wave alternans (IAA) and the slope of heart rate turbulence (TS) for classification of SCD and PFD.

Methods: Holter ECG recordings of 597 CHF patients with sinus rhythm enrolled in the MUSIC study were analyzed and Δα, IAA and TS were obtained.

Removing ventricular far-field signals in intracardiac electrograms during stable atrial tachycardia using the periodic component analysis.

Background: Intracardiac electrograms are an indispensable part during diagnosis of supraventricular arrhythmias, but atrial activity (AA) can be obscured by ventricular far-fields (VFF). Concepts based on statistical independence like principal component analysis (PCA) cannot be applied for VFF removal during atrial tachycardia with stable conduction.

Methods: A database of realistic electrograms containing AA and VFF was generated.

Characterization of radiofrequency ablation lesion development based on simulated and measured intracardiac electrograms.

Radiofrequency ablation (RFA) therapy is the gold standard in interventional treatment of many cardiac arrhythmias. A major obstacle is nontransmural lesions, leading to recurrence of arrhythmias. Recent clinical studies have suggested intracardiac electrogram (EGM) criteria as a promising marker to evaluate lesion development.

Ectopic beats and their influence on the morphology of subsequent waves in the electrocardiogram.

Ventricular ectopic beats (VEBs) trigger a characteristic response of the heart called heart rate turbulence(HRT). The HRT can be used to predict sudden cardiac death in patients with a history of myocardial infarction. In this work, we present a reliable algorithm to detect and classify ectopic beats.

An automated approach to analyze microstructural remodeling from confocal microscopies of ventricular myocytes from diseased hearts.

Various types of heart disease are associated with structural remodeling of cardiac cells. In this work, we present a software framework for automated analyses of structures and protein distributions involved in excitation-contraction coupling in cardiac muscle cells (myocytes). The software framework was designed for processing sets of three-dimensional image stacks, which were created by fluorescent labeling and scanning confocal microscopy of ventricular myocytes from a rabbit infarction model.

Prognostic significance of Ki-67 immunostaining in nonmetastatic renal cell carcinoma.

Purpose: Fresh tissue samples from nonmetastatic renal cell carcinoma (RCC) patients were analyzed by Ki-67 immunostaining to determine the prognostic significance of this tumor-biologic parameter.

Materials And Methods: In a prospective study, Ki-67 immunostaining was performed on frozen sections of histologically proven node-negative RCC from 58 patients operated on between 1986 and 1988 to examine the method's prognostic value and its association with other clinicopathologic parameters such as tumor stage (pT) and grade (G).

Results: The percentage of Ki-67-positive cells (ie, the proliferation rate [PR]) of all 58 RCC tumors ranged between 1% and 23%, while normal renal tissue exhibited PRs up to 2% only.

In vitro sensitivity testing of human renal cell carcinoma with cytostatic agents and interferon alpha-2a.

Samples of 38 human renal cell carcinomas (RCC) were subjected to routine histopathological examination but also to in vitro sensitivity testing with mitomycin C, vinblastine and interferon Alpha-2a at various concentrations corresponding to serum titers recommended to be effective in vivo, employing a monolayer assay. Extending earlier in vitro studies, both tumor cell kill rates (TCKR) and proliferation rates (PR) were assessed. Following in vitro preparation the tumor cell cultures were simultaneously exposed to the anticancer drugs listed above.

[In vitro sensitivity testing of human kidney tumors to cytostatic drugs with a rapid in vitro test].

We present a new modified in vitro culture assay for primary human renal cell carcinoma similar to the 'soft agar clonogenic assay'. However, the carrying out and expense of metrology are more simplified, allowing tumor-specific chemotherapeutic drug sensitivity testing under easier conditions. Twelve different samples of human renal carcinoma and one sample of a transitional cell carcinoma of the renal pelvis were tested for in vitro chemotherapy sensitivity using this modified colony-forming assay.