Biomarkers of Cardiac Stress and Injury in Athletes: What Do They Mean?

Purpose of the Review

Markers of myocardial stress, including troponin, creatine kinase, and brain natriuretic peptide are frequently elevated after endurance athletic pursuits. Here, we summarize the current literature pertaining to the potential mechanism of cardiac enzyme release in athletes and seek to determine the clinical implications of these findings.

Recent Findings

Recent studies have highlighted the potential adverse cardiac effects of long-term extreme endurance exercise. While troponin release occurs in a pattern distinct from ischemic damage, BNP release has been correlated with right ventricular dysfunction and is likely related to wall stress from prolonged increases in cardiac output. Higher intensity pre-race training regimes are associated with lower race-day enzyme release.

Summary

While the holistic benefits of regular moderate exercise are indisputable, recent studies have raised concerns about the potential risks of extreme endurance exercise. Release of serum biomarkers suggesting myocardial damage was first described in the 1970s, yet our understanding of the implications of these findings remains incomplete. The mechanisms of release are complex but appear to be primarily physiological phenomena rather than pathologic.

     

Network Analysis of Internet Addiction Symptoms Among a Clinical Sample of Japanese Adolescents with Autism Spectrum Disorder

Journal of Autism and Developmental Disorders - In the present study, we employed network analysis that conceptualizes internet addiction (IA) as a complex network of mutually influencing symptoms...     

A new finite element approach for near real‐time simulation of light propagation in locally advanced head and neck tumors

Background and Objectives

Several clinical studies suggest that interstitial photodynamic therapy (I‐PDT) may benefit patients with locally advanced head and neck cancer (LAHNC). For I‐PDT, the therapeutic light is delivered through optical fibers inserted into the target tumor. The complex anatomy of the head and neck requires careful planning of fiber insertions. Often the fibers' location and tumor optical properties may vary from the original plan therefore pretreatment planning needs near real‐time updating to account for any changes. The purpose of this work was to develop a finite element analysis (FEA) approach for near real‐time simulation of light propagation in LAHNC.

Methods

Our previously developed FEA for modeling light propagation in skin tissue was modified to simulate light propagation from interstitial optical fibers. The modified model was validated by comparing the calculations with measurements in a phantom mimicking tumor optical properties. We investigated the impact of mesh element size and growth rate on the computation time, and defined optimal settings for the FEA. We demonstrated how the optimized FEA can be used for simulating light propagation in two cases of LAHNC amenable to I‐PDT, as proof‐of‐concept.

Results

The modified FEA was in agreement with the measurements (P = 0.0271). The optimal maximum mesh size and growth rate were 0.005–0.02 m and 2–2.5 m/m, respectively. Using these settings the computation time for simulating light propagation in LAHNC was reduced from 25.9 to 3.7 minutes in one case, and 10.1 to 4 minutes in another case. There were minor differences (1.62%, 1.13%) between the radiant exposures calculated with either mesh in both cases.

Conclusions

Our FEA approach can be used to model light propagation from diffused optical fibers in complex heterogeneous geometries representing LAHNC. There is a range of maximum element size (MES) and maximum element growth rate (MEGR) that can be used to minimize the computation time of the FEA to 4 minutes. Lasers Surg. Med. 47:60–67, 2015. © 2015 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.     

Biochemical Markers for Alcoholism

A panel of blood tests, purportedly markers for alcohol abuse, were examined in 543 relatively healthy alcoholics entering ambulatory rehabilitation treatment. Individual tests were too low in sensitivity: gamma-glutamyl transpeptidase was abnormally high in only 49%, then mean corpuscular volume (45%), high density lipoprotein cholesterol (HDLC) (25%), serum glutamic oxaloacetic transaminase (SGOT) (28%), and blood alcohol (21%). HDLC was of low sensitivity, generally unaffected by liver disease, and related to quantitation of recent alcohol consumed. Combining seven markers, 82% of males and 71% females had at least one abnormally high value. Histories of heavy recent drinking, positive blood alcohol levels on admission, and manifest liver disease on physical examination or by hyperbilirubinemia were associated with high sensitivities of individual and pooled markers. The biochemical markers studied can be useful to suggest alcohol abuse, especially in some populations of drivers. In other populations of alcoholics, especially with intermittent alcohol or recent abstinence, their sensitivities were so low as to discourage extensive reliance on their use. The diagnosis of alcoholism continues to depend on clinical history of alcohol-related problems, including social, familial, legal, medical, psychological, and economic.