Clinical Experiments (clinical + experiment)

Distribution by Scientific Domains


Selected Abstracts


A study on non-invasive detection of blood glucose concentration from human palm perspiration by using artificial neural networks

EXPERT SYSTEMS, Issue 3 2010
Hamdi Melih Sarao
Abstract: In this paper the relationship between blood glucose concentration and palm perspiration rate is studied as a non-invasive method. A glucose concentration range from 83 mg/dl to 116.5 mg/dl is examined. An artificial neural network (ANN) trained by the Levenberg,Marquardt algorithm is developed to detect the performance indices based on the one- and two-input variables. A data set for 72 volunteers is used for this study. Data of 36 volunteers are used for training the ANN and data of 36 volunteers were reserved for testing. Results of the study are acceptable with an error of 8.38% for the Elman neural network and 8.77% for the multilayer neural network. Therefore, the palm perspiration rate may be used as a good indicator for detecting glucose concentration in blood. This non-invasive method has advantages such as time saving, cost etc. over other methods and it is painless. The results of clinical experiments, follow-up methods and other applications are presented. [source]


Color adaptation for anomalous trichromats

INTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 1 2004
Yong Man Ro
Abstract In this article, we propose a content-based color adaptation method for color vision impairment, especially for anomalous trichromats, to improve color information accessibility. Color degradation caused by anomalous trichromacy is compensated in digital color content with a range of the visible spectrum corresponding to color deficiency characteristics. To verify the usefulness of the proposed method, we performed clinical experiments as well as computer simulations. The results of both the experiments and the simulations show that the proposed adaptation could convey better color information to anomalous trichromats. © 2004 Wiley Periodicals, Inc. Int J Imaging Syst Technol 14, 16,20, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.20002 [source]


Use of intravenous lidocaine to prevent reperfusion injury and subsequent multiple organ dysfunction syndrome

JOURNAL OF VETERINARY EMERGENCY AND CRITICAL CARE, Issue 3 2003
Benjamin H. Cassutto DVM
Abstract Objective: The objective of this article is to review the human and veterinary literature and provide evidence for the potential beneficial effects of intravenous (IV) lidocaine hydrochloride in preventing post-ischemic,reperfusion injury, the systemic inflammatory response syndrome (SIRS), and subsequent multiple organ dysfunction syndrome (MODS). Human data synthesis: Lidocaine is a local anesthetic and antiarrhythmic agent that has been used for years in human and veterinary medicine for the treatment of ventricular dysrhythmias associated with blunt cardiac trauma, myocardial ischemia, and cardiac surgery. More recently, the drug has been touted as a scavenger of reactive oxygen species (ROS), and has been used to prevent reperfusion dysrhythmias after treatment of myocardial infarction, cross-clamping of the aorta, and in trauma medicine. Veterinary data synthesis: Although no clinical experiments with prophylactic intravenous lidocaine exist in veterinary medicine, there is a large body of evidence from experimental animals that support the use of lidocaine as a Na+/Ca2+ channel blocker, superoxide and hydroxyl radical scavenger, inflammatory modulator, and potent inhibitor of granulocyte functions. Lidocaine is being used in some clinical situations in an attempt to prevent the SIRS in veterinary trauma patients.a,b Conclusions: A large body of experimental evidence exists supporting the use of lidocaine as an anti-oxidant and inflammatory modulator useful in preventing reperfusion injury. With the lack of cost-effective and safe treatments for reperfusion injury in veterinary and human trauma medicine, the use of IV lidocaine to prevent the ensuing inflammatory response and MODS makes it an attractive addition to existing treatments. Therefore, it is essential that prospective clinical trials involving lidocaine as a treatment for prevention of reperfusion injury be performed in companion animals to demonstrate its safety and efficacy. [source]


Pharmacokinetic parameters estimation using adaptive Bayesian P-splines models

PHARMACEUTICAL STATISTICS: THE JOURNAL OF APPLIED STATISTICS IN THE PHARMACEUTICAL INDUSTRY, Issue 2 2009
Astrid Jullion
Abstract In preclinical and clinical experiments, pharmacokinetic (PK) studies are designed to analyse the evolution of drug concentration in plasma over time i.e. the PK profile. Some PK parameters are estimated in order to summarize the complete drug's kinetic profile: area under the curve (AUC), maximal concentration (Cmax), time at which the maximal concentration occurs (tmax) and half-life time (t1/2). Several methods have been proposed to estimate these PK parameters. A first method relies on interpolating between observed concentrations. The interpolation method is often chosen linear. This method is simple and fast. Another method relies on compartmental modelling. In this case, nonlinear methods are used to estimate parameters of a chosen compartmental model. This method provides generally good results. However, if the data are sparse and noisy, two difficulties can arise with this method. The first one is related to the choice of the suitable compartmental model given the small number of data available in preclinical experiment for instance. Second, nonlinear methods can fail to converge. Much work has been done recently to circumvent these problems (J. Pharmacokinet. Pharmacodyn. 2007; 34:229,249, Stat. Comput., to appear, Biometrical J., to appear, ESAIM P&S 2004; 8:115,131). In this paper, we propose a Bayesian nonparametric model based on P-splines. This method provides good PK parameters estimation, whatever be the number of available observations and the level of noise in the data. Simulations show that the proposed method provides better PK parameters estimations than the interpolation method, both in terms of bias and precision. The Bayesian nonparametric method provides also better AUC and t1/2 estimations than a correctly specified compartmental model, whereas this last method performs better in tmax and Cmax estimations. We extend the basic model to a hierarchical one that treats the case where we have concentrations from different subjects. We are then able to get individual PK parameter estimations. Finally, with Bayesian methods, we can get easily some uncertainty measures by obtaining credibility sets for each PK parameter. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Brain oscillations forever , neurophysiology in future research of child psychiatric problems

THE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 1-2 2009
Aribert Rothenberger
For decades neurophysiology has successfully contributed to research and clinical care in child psychiatry. Recently, methodological progress has led to a revival of interest in brain oscillations (i.e., a band of periodic neuronal frequencies with a wave-duration from milliseconds to several seconds which may code and decode information). These oscillations will nurture future information processing research during normal and pathological brain development, allowing us to investigate basic neuronal connectivity as well as interactions of brain systems and their modulation (e.g., by temporal neuronal synchronisation) as close correlates of behaviour and intermediate phenotypes from genes to behavioural variations. Especially, a systematic neurodynamic look at transitional processes from rest to stimulus-triggered goal-directed performance will aid behavioural understanding and guidance of children. Preliminary data suggest two separate oscillatory mechanisms in this respect. One is ongoing from pre- to post-stimulus processing and related to quantitative modification of behaviour, while another is merely related to qualitative effects of behaviour and reflects ,on-top' post-stimulus processing by temporal neuronal synchronisation of the oscillatory network in question. Suggested neurodynamic models may be tested in multilevel clinical experiments as well as in the framework of computational neuropsychiatry. [source]


Large Bore Catheters with Surface Treatments versus Untreated Catheters for Vascular Access in Hemodialysis

ARTIFICIAL ORGANS, Issue 7 2004
Rolf Bambauer
Abstract:, Infection, thrombosis, and stenosis are among the most frequent complications associated with blood-contacting catheters. Complications resulting from infection remain a major problem for hemodialysis catheters, with significant numbers of catheters being removed due to catheter-related sepsis. Numerous strategies have been employed to reduce the occurrence of infection and im-prove long-term outcomes, with varying degrees of success. The most important is the careful and sterile handling by the attending staff of the catheters during hemodialysis treatments to minimize or stop a microbial colonization of the skin and the catheter. Another approach is coating the external surface of the catheters with substances which are antibacterial like silver and/or substances with low thrombogenicity like silicone. This investigation reviews results of animal and clinical experiments conducted to assess the efficacy and biocompatibility of silver and silicone coated dialysis catheters. It is concluded that silver coatings can reduce bacterial colonization and occurrence of infection associated with these devices. The catheters employing ion implantation of silicone rubber showed low thrombogenicity. Results of the studies indicate that ion beam based processes can be used to improve thrombus and infection resistance of blood contacting catheters. A new development is the microdomain structured surface (PUR-SMA coated catheters). Preliminary results with these catheters are very encouraging. [source]