Can the Roche hemolysis index be used for automated determination of cell-free hemoglobin? A comparison to photometric assays

ObjectivesThe aim of this study was to develop a novel method for automated quantification of cell-free hemoglobin (fHb) based on the HI (Roche Diagnostics).MethodsThe novel fHb method based on the HI was correlated with fHb measured using the triple wavelength methods of both Harboe [fHb, g/L = (0.915 * HI + 2.634)/100] and Fairbanks et al. [fHb, g/L = (0.917 * HI + 2.131)/100]. fHb concentrations were estimated from the HI using the Roche Modular® automated platform in self-made and commercially available quality controls, as well as samples from a proficiency testing scheme (INSTAND). The fHb using Roche automated HI results were then compared to results obtained using the traditional spectrophotometric assays for one hundred plasma samples with varying degrees of hemolysis, lipemia and/or bilirubinemia.ResultsThe novel method using automated HI quantification on the Roche Modular® clinical chemistry platform correlated well with results using the classical methods in the 100 patient samples (Harboe: r = 0.9284; Fairbanks et al.: r = 0.9689) and recovery was good for self-made controls. However, commercially available quality controls showed poor recovery due to an unidentified matrix problem.ConclusionsThe novel method produced reliable determination of fHb in samples without interferences. However, poor recovery using commercially available fHb quality control samples currently greatly limits its usefulness.     

Using distance education to promote the transfer of motivational interviewing skills among behavioral health professionals

This study evaluated the effectiveness of distance education for training behavioral health professionals. Five live video workshops that covered key elements of Motivational Interviewing (MI) were delivered. The programs occurred a month apart, each 3 hours long. The programs used compressed video, transmitting the video signal through telephone lines. The audience was staff at substance abuse treatment organizations throughout the state of Arizona. Participants completed assessments regarding their training experiences, knowledge and self-efficacy in MI, and their satisfaction with the training, prior to, during, and subsequent to the workshops. Participation in the five workshops varied; the first workshop had the largest attendance of 351, the fourth the lowest of 92; 145 participants attended all five workshops. Participants expressed moderate levels of satisfaction with most aspects of the training, although some expressed frustration with interrupted audio or video signals during the programs. The handouts and videotaped examples of MI were identified as the more helpful aspects of the training. Participants reported statistically significant improvements in their self-perceived knowledge and skills. They demonstrated a statistically significant but clinically insignificant increase in knowledge. A small group of participants provided audiotapes of actual counseling sessions. These participants demonstrated minimal improvement in skills across the study that were not statistically significant. These results are discussed in terms of their implications for future research in the use of distance education as a technology transfer tool in the addiction treatment profession.     

Attention-deficit/hyperactivity disorder: a shift toward resilience?

Children with attention-deficit/hyperactivity disorder (ADHD) present a concern across clinical, academic, and social domains. However, a subset of these children does fairly well symptomatically and functionally. This article employs a resilience framework to organize the research on factors that promote favorable outcomes in ADHD. A PubMed search was conducted using key words: resilience and ADHD. Of particular interest were articles focusing on modifiable protective factors, such as parenting and pharmacotherapy. There is consensus that genetics strongly contributes to the etiology of ADHD. Parental, peer, and environmental factors may interact with genes to moderate the developmental expression of ADHD. Pharmacotherapy research reveals that medications exert positive effects of modest magnitude in academic achievement, social functioning and quality of life. However, there is insufficient evidence to determine whether treatment can modify developmental outcomes. Efforts to strengthen family support along with access to health and educational resources may also optimize outcomes.     

Presence of intestinal Mycobacterium avium subspecies paratuberculosis (MAP) DNA is not associated with altered MMP expression in ulcerative colitis

Background

Mycobacterium avium subspecies paratuberculosis (MAP) is suspected to be a causative agent in human Crohn's disease (CD). Recent evidence suggests that pathogenic mycobacteria and MAP can induce the expression of Matrix Metalloproteinases (MMP), which are the main proteases in the pathogenesis of mucosal ulcerations in inflammatory bowel disease (IBD). Within this study we assessed the prevalence of intestinal MAP specific DNA in patients with Crohn's disease, ulcerative colitis (UC), and healthy controls. We further analysed regulation patterns of MMPs in mucosal tissues of UC patients with and without intestinal MAP DNA detection.

Methods

Colonic biopsy samples were obtained from 63 Norwegian and German IBD patients and 21 healthy controls. RNA was quantified by quantitative real-time polymerase chain reaction (PCR) to study MMP gene expression in both pathological and healthy mucosal specimens. The presence of MAP DNA in colonic mucosa was examined using MAP specific PCR.

Results

MAP DNA was detected in 20% of UC patients and 33% of healthy controls but only in 7% of patients with CD. UC patients treated with corticosteroids exhibited a significantly increased frequency of intestinal MAP DNA compared to those not receiving corticosteroids. Expression of MMP-1, -2, -7, -9, -13, -19, -28 and TNF-α did not differ between UC patients with presence of intestinal MAP DNA compared to those without. MMP-2, MMP-9 and MMP-13 were significantly decreased in UC patients receiving corticosteroids.

Conclusions

The presence of intestinal MAP specific DNA is not associated with altered MMP expression in UC in vivo. Corticosteroids are associated with increased detection of intestinal MAP DNA and decreased expression of certain MMPs. Frequent detection of MAP DNA in healthy controls might be attributable to the wide environmental distribution of MAP and its presence in the food-chain.     

Registration of 3D trans-esophageal echocardiography to X-ray fluoroscopy using image-based probe tracking

Two-dimensional (2D) X-ray imaging is the dominant imaging modality for cardiac interventions. However, the use of X-ray fluoroscopy alone is inadequate for the guidance of procedures that require soft-tissue information, for example, the treatment of structural heart disease. The recent availability of three-dimensional (3D) trans-esophageal echocardiography (TEE) provides cardiologists with real-time 3D imaging of cardiac anatomy. Increasingly X-ray imaging is now supported by using intra-procedure 3D TEE imaging. We hypothesize that the real-time co-registration and visualization of 3D TEE and X-ray fluoroscopy data will provide a powerful guidance tool for cardiologists. In this paper, we propose a novel, robust and efficient method for performing this registration. The major advantage of our method is that it does not rely on any additional tracking hardware and therefore can be deployed straightforwardly into any interventional laboratory. Our method consists of an image-based TEE probe localization algorithm and a calibration procedure. While the calibration needs to be done only once, the GPU-accelerated registration takes approximately from 2 to 15 s to complete depending on the number of X-ray images used in the registration and the image resolution. The accuracy of our method was assessed using a realistic heart phantom. The target registration error (TRE) for the heart phantom was less than 2 mm. In addition, we assess the accuracy and the clinical feasibility of our method using five patient datasets, two of which were acquired from cardiac electrophysiology procedures and three from trans-catheter aortic valve implantation procedures. The registration results showed our technique had mean registration errors of 1.5-4.2 mm and 95% capture range of 8.7-11.4 mm in terms of TRE.     

Patient-specific electromechanical models of the heart for the prediction of pacing acute effects in CRT: a preliminary clinical validation

Cardiac resynchronisation therapy (CRT) is an effective treatment for patients with congestive heart failure and a wide QRS complex. However, up to 30% of patients are non-responders to therapy in terms of exercise capacity or left ventricular reverse remodelling. A number of controversies still remain surrounding patient selection, targeted lead implantation and optimisation of this important treatment. The development of biophysical models to predict the response to CRT represents a potential strategy to address these issues. In this article, we present how the personalisation of an electromechanical model of the myocardium can predict the acute haemodynamic changes associated with CRT. In order to introduce such an approach as a clinical application, we needed to design models that can be individualised from images and electrophysiological mapping of the left ventricle. In this paper the personalisation of the anatomy, the electrophysiology, the kinematics and the mechanics are described. The acute effects of pacing on pressure development were predicted with the in silico model for several pacing conditions on two patients, achieving good agreement with invasive haemodynamic measurements: the mean error on dP/dt_max is 47.5 ± 35 mm Hg s⁻¹, less than 5% error. These promising results demonstrate the potential of physiological models personalised from images and electrophysiology signals to improve patient selection and plan CRT.