N-acetylcysteine exerts therapeutic action in a rat model of allergic rhinitis.

BACKGROUND: The pathophysiologic mechanism of allergy is dependent on the action of many redox-sensitive proinflammatory mediators. However, even though redox disturbances are believed to be a hallmark of inflammation, little is known of the effect of redox imbalance to the pathophysiology of allergic rhinitis. We thus opted to investigate the relation of oxidative stress and allergic rhinitis, through the utilization of a potent antioxidant substance (N-acetylcysteine [NAC]) in a rat model of allergic rhinitis and the evaluation of its action on specific markers of inflammation. METHODS: NAC (50 mg/kg and 250 mg/kg) was intraperitoneally administered to ovalbumin (OVA)-sensitized rats prior to intranasal challenge with OVA. Mucosal congregation of inflammatory cells (eosinophils and mast cells), mucosal expression of redox-sensitive enzymes (inducible nitric oxide synthase [iNOS] and cyclooxygenase 2 [COX-2]), and the blood levels of a key proinflammatory mediator (tumor necrosis factor-α [TNF-α]) were evaluated. RESULTS: Intranasal OVA challenges lead to mucosal inflammation, induction of the mucosal expression of iNOS and COX-2 and elevation of TNF-α blood levels. NAC significantly inhibited accumulation of inflammatory cells and downregulated iNOS expression and TNF-α serum levels. The role of COX-2 appeared to be 2-fold and its expression was divergently modulated by NAC. CONCLUSION: Our findings suggest that redox balance is involved in the pathophysiology of allergic rhinitis in rats and that NAC can potentially suppress the allergen-induced nasal inflammatory cascade. The investigation of the role of oxidative stress in atopy could help in the evaluation of the therapeutic potential of antioxidant substances in allergic diseases.

Cerebrospinal fluid proteins in the diagnosis of Alzheimer's disease.

Alzheimer's disease (AD) is rapidly grooving incidence that affects millions of people worldwide, therefore there is an immediate need for its' early and accurate diagnosis. Many research studies have been performed on possible accurate and reliable diagnostic biomarkers of AD. This review study provides an overview on the cerebrospinal fluid (CSF) proteins that are used as biochemical markers for the early diagnosis of AD and their future prospects, as well as relevant patents.

The clockwise rotation of myocardial fiber orientation from epicardial to endocardial surface in left ventricular free wall in a post-mortem human heart.

Following fixation and MRI imaging a post-mortem human heart was sliced at the sagittal plane. Each anatomical section was then cut into smaller segments and each one was objected to classical histology process. The resulting microscopy slides were digitalized with a scanner. The histological section reconstruction was achieved using Adobe Photoshop CS2(R). Using specific software, called FiberCad, the user can define and draw (with the assistance of optical microscope) those fibers that are parallel and those fibers that are vertical to the slides plane. To better align the histological 3D reconstruction, the software is equipped with an option that allows the user to make best possible fit between histological and MRI slices. We present the consequent sagittal sections of LV free wall (from epicardial to endocardial surface), whereby the clockwise rotation of the mean orientation of the fibers that are on the plane of sectioning is clearly evident. We present a post mortem analysis of the complete LV free wall of a human heart.

One heart, two bodies: a simulation study of body surface potential differences between donor and recipient of heart transplantation.

In cardiac transplantation has been recognized some "abnormalities" in recipient ECG. We investigated the influence of heart geometrical position within the chest cavity as well as somatometric parameters on body surface torso potentials. Two control patients with different Body Mass Index (BMI) were undergone a chest MRI scan. Using specific software we created two tetrahedral meshes that could be applied in our study. A post-mortem human heart was undergone a MRI scan and we also created its tetrahedral mesh. Using second software we extracted the heart mesh of control's torsos and we replaced them with the mesh of the post-mortem heart. The last program also assessed the influence of heart (re)positioning within the thorax, on the body surface potentials. The Finite Elements Method (FEM) was used to solve the forward electrocardiographic problem for both torsos, under the assumption that all the ventricular myocardium of the one post-mortem heart was excited. FEM was also applied in simulating Body Surface Potential Mapping (BSPM) on the first thorax torso for nine different heart positions. For BSPM, FEM has been applied on Poison equation. The results show higher BSPM in patient with lower BMI and significant changes in BSPM when heart was rotated round its long axis. Conversely, the heart shifts (long x- or y- axis) didn't cause significant changes on simulated BSPM.

Usefulness of event-related potentials in the assessment of mild cognitive impairment.

BACKGROUND: The aim of this study was to determine if changes in latencies and amplitudes of the major waves of Auditory Event-Related Potentials (AERP), correlate with memory status of patients with mild cognitive impairment (MCI) and conversion to Alzheimer's disease (AD). 91 patients with MCI (mean +/- SD age = 66.6 +/- 5.4, MMSE score = 27.7) and 30 age-matched healthy control (AMHC) subjects (mean +/- SD age = 68.9 +/- 9.9) were studied. 54 patients were re-examined after an average period of 14(+/- 5.2) months. During this time period 5 patients converted to AD. Between-group differences in latency and amplitude of the major AERP waves (N200, P300 and Slow Wave) were determined. Within each group, correlation coefficients (CC) between these characteristics of the different AERP waves were calculated. Finally, for patients, CCs were determined among each AERP wave and their age and MMSE scores. Confirmatory factor analysis (CFA) was used to examine the underlying structure of waveforms both in the control and the patient groups. RESULTS: Latencies of all major AERP components were prolonged in patients compared to controls. Patients presented with significantly higher N200 amplitudes, but no significant differences were observed in P300 amplitudes. Significant differences between follow-up and baseline measurements were found for P300 latency (p = 0.009), N200 amplitude (p < 0.001) and P300 amplitude (p = 0.05). MMSE scores of patients did not correlate with latency or amplitude of the AERP components. Moreover, the establishment of a N200 latency cut-off value of 287 ms resulted in a sensitivity of 100% and a specificity of 91% in the prediction of MCI patients that converted to AD. CONCLUSION: Although we were not able to establish significant correlations between latencies and amplitudes of N200, P300 and SW and the patients' performance in MMSE, which is a psychometric test for classifying patients suffering from MCI, our results point out that the disorganization of the AERP waveform in MCI patients is a potential basis upon which a neurophysiologic methodology for identifying and "staging" MCI can be sought. We also found that delayed N200 latency not only identifies memory changes better than the MMSE, but also may be a potential predictor of the MCI patients who convert to AD.

Arrhythmogenesis in patients with stable chronic obstructive pulmonary disease.

OBJECTIVE: Fatal arrhythmias are a common cause of death in chronic obstructive pulmonary disease (COPD). Two major hypotheses for arrhythmogenesis in COPD have been proposed: arrhythmias are a consequence of hypoxaemia, hypercapnia or (tissue localised) acid-base disturbances, or arrhythmias are the result of the autonomic neuropathy that characterises COPD. Our objective was to verify these two hypotheses. METHODS: A total of 29 consecutive COPD patients (seven men and 22 women, mean age 63.75 +/- 10.50 years) were included in the study. Pulmonary function tests were performed and arterial blood gases were obtained simultaneously. Twelve-lead electrocardiograms were recorded from all patients. QT dispersion, which is a measure of myocardial repolarisation heterogeneity, and the coefficient of variation of the RR interval, which is a measure of heart rate variability, were calculated. RESULTS: Of the parameters measured, only the coefficient of variation of the RR interval appeared to be related to arrhythmias, since it correlated positively with arterial oxygen pressure (r = 0.418, statistical significance set at P < 0.05). CONCLUSIONS: Our results rule out the electropathy hypothesis and underline the role of autonomic neuropathy as the most probable arrhythmogenic mechanism in hypoxaemic COPD patients. Our interpretation is based on the fact that hypoxaemia decreases heart rate variability and on the strong association between the reduction in heart rate variability and arrhythmogenesis.

Clinical experience from 1000 consecutive cardiovascular MRI cases at a tertiary referral medical center.

We present our experience from the first 1000 clinical cardiovascular magnetic resonance imaging cases performed at our institution. The case load included pediatric and adult patients with a male predominance (two thirds of the patient population). The spectrum of diseases was very broad, and included myopathic, atherosclerotic, vascular, valvular, pericardial, neoplasmatic and congenital heart disease. Our experience demonstrates the areas where cardiovascular magnetic resonance imaging has established value and suggests areas of future development.

Visual function and visual perception in cerebral palsied children.

PURPOSE: To investigate visual function and perception in cerebral palsied (CP) children. METHODS: A total of 105 congenitally CP children (aged 6-15 years), without severe mental retardation, were classified into three groups: those with spastic quadriplegia, spastic diplegia and spastic hemiplegia. Data collected included patient history, IQ, refraction, far and near visual acuity, position of the eyes and eye movements, visual fields, colour perception, stereoacuity, slit lamp and fundoscopic examinations, and evaluation of visual perception. The results were compared with a control group from the general paediatric population. RESULTS: The IQ of the CP children ranged between 70 and 100. A total of 59% of them had best corrected distance visual acuity <6/6, with 25.5% <6/9. Near visual acuity was also reduced (70.1% scored <6/6 and 38.4% scored <6/9). Incidence of refractive errors was higher than in the control group (hypermetropia in 43.8% of the eyes, myopia 16.19% and astigmatism 40.9%) as was the incidence of strabismus (26.7% esotropic and 27.6% exotropic). In visual field testing, 80.95% of CP children were normal. A total of 94.28% had normal colour perception and 89.52% were free of ocular pathology. Stereopsis was abnormal or absent in 85.71% of the cases. Visual perception was markedly reduced: in 57.14% of the cases it was less than or equal to that of 6-year-old children; in 26.66% equal to that of 6- to 7.5-year-old children, and in 16.2% of the cases greater than or equal to that of 7.5-year-old children. CONCLUSIONS: In the absence of severe mental retardation, CP children have deficient visual skills. It is suggested that the poor visual skills of CP children are a separate, identifiable factor compounding the adverse effects of mental retardation.

Visual function and execution of microsaccades related to reading skills, in cerebral palsied children.

This article investigates the ability of cerebral palsied (CP) children to execute microsaccades. One-hundred and five congenitally CP school aged children (6 to 15 years old), without severe mental retardation, were classified into three groups: those with spastic quadriplegi, spastic diplegics, and spastic hemiplegics on the basis of: (1) patient anamnesis, (2) IQ estimation, (3) evaluation of the microsaccadic skills with the Developmental Eye Movement test (DEM). Their performance in these tests was compared with a control group from the general pediatric population. IQ of the CP children ranged between 70 and 100; the microsaccadic skills were severely affected: only 19% of the CP children had normal function, 20.9% of the CP children appeared with a pure oculomotor problem, 32.4% of the CP children had a visual-perceptual problem, and 27.7% of the CP children had a combined oculomotor and visual perceptual problem. CP children, in the absence of severe mental retardation, have disturbed visual skills and visual perception that usually leads to reading difficulties. It is also suggested that microsaccadic skills of CP children is an identifiable factor compounding the adverse effects of mental retardation on reading skills.

A training network for introducing telemedicine, telecare and hospital informatics in the Adriatic-Danube-Black Sea region.

DIMNET is a training mechanism for a region of central Europe. The aim is to upgrade the information technology skills of local hospital personnel and preserve their employability following the introduction of medical informatics. DIMNET uses Internet-based virtual classrooms to provide a 200-hour training course in medical informatics. Training takes place in the cities of Drama, Kavala, Xanthi and Varna. So far, more than 600 people have benefited from the programme. Initial results are encouraging. DIMNET promotes a new vocational training culture in the Balkans and is supported by local governments that perceive health-care as a fulcrum for economic development.

The Varna-Thessaloniki telemedical collaboration in setting up a regional transborder transplantation network.

In most Balkan countries, with the exception of Greece, transplantation is very rare and equality of access does not exist. In 2003, a Balkan partnership was established called SETNET (South-Eastern European Transplantation Network) for the promotion of transplantation. The objectives are to bring about the diffusion of transplantation techniques and practices in the Balkans, to increase public support for and participation in transplantation, and to eliminate the disparities in access to good health-care. SETNET is already beginning to generate data for an analysis of transplantation-related needs in the Balkans and to accelerate cross-border data exchange in transplantation-related emergencies. In the next few years, a regional training programme will be introduced for all health-care staff involved in transplantation. A regional organ procurement and transplantation network will be set up to utilize the existing telemedicine infrastructure. If successful, it will also prove that telemedicine infrastructures, however modest, can be the backbone for other, far-reaching human networks.

A simple telemedicine system to provide second-opinion advice to the patients of an Albanian diagnostic centre.

Since August 2003, the IKEDA Klinika diagnostic centre in Tirana, Albania, has offered patients telemedical help from Greece. The teleconsultation service is based on Internet technologies adapted to telemedical use, including the use of forms (e.g. for the patient history), multimedia file exchanges (e.g. for radiographs and electroencephalograms) and videoconferencing. The teleconsultants assist in treatment planning and, when necessary, in organizing the transfer of patients to Greece. The four cornerstones of the service are: the provision of second opinions by telemedicine; assistance in treatment planning; assistance to patients during transfer; and the continuity of medical care on their repatriation. Based on the first six months of operation, we estimate that, if bureaucratic visa restrictions to patient movement between Albania and Greece are removed, more than 2000 patients per year will benefit from the service and more than 400 patients will be transferred to Greek hospitals for treatment.

Real time estimation of physical activity and physiological performance reserves of players during a game of soccer.

The need for ever increasing achievements in athletic performance is pushing the acquisition costs and salaries of top performers to unprecedented heights. Individual talent, good physical condition and relentless training, however, do not by themselves guarantee success of the team effort. Team performance is determined by game strategy and team coordination. Ideally, during a game, the team coach should be able to gauge the instantaneous physical condition and performance reserves of each player on the team and direct game strategy accordingly. Our experimental setup explores the feasibility of objectively estimating, in real time, the intensity of physical activity and the physiological performance reserves of each and every player on the team during a game of soccer.

The Korydallos, Greece, prisons telemedicine system experience: why technology alone is not a sufficient condition.

In 1999 the Greek Ministry of Justice decided to utilise telemedicine to improve health services in the largest prison in Greece (Korydallos Prison). The Nikea Hospital in Piraeus undertook to support the effort. For 12 months following installation, intensive "hands-on" training on the use of the system was offered to the staff of both the Korydallos Prison and the Nikea Hospital. However serious operational problems related either to prison bureaucracy or to the inflexibility the Greek National Health Service has annulled the effectiveness of the Korydallos Prison telemedicine system. Still, analysis of the system development history reveals that: (1) if freed from bureaucratic and labour related obstacles, prison telemedicine is a viable option. (2) Telemedicine can avert transfers to out-of-prison medical facilities. (3) If properly implemented, telemedicine can generate substantial savings and (4) telemedicine can greatly improve the quality of care available to prisoners.

A clinical and educational telemedicine link between Bulgaria and Greece.

During its transition to a free economy, Bulgaria benefited from foreign aid provided by Greece. One of the projects was the clinical and educational telemedicine link between the Medical University of Varna in Bulgaria and the Faculty of Medicine of Aristotle University of Thessaloniki in Greece. This began in 1997. In terms of the educational activities, the Bulgarian side of the network supports (a) electronic design and publishing activities, (b) web hosting and mail server activities and (c) satellite communications. In addition it supports an electronic classroom equipped with personal workstations, multimedia projectors and videoconference facilities. Communications are via the ISDN network. In terms of its telemedicine activities, the network provides remote medical assistance to "language handicapped" travellers and to migrant workers in both countries. The main clinical experience is remote consultations in immunology. This admittedly limited experience demonstrates that telemedicine can be used to provide assistance to remote colleagues. In cases where the patient cannot communicate with the attending physician, the use of telemedicine can greatly improve the quality of care available to travellers and migrant workers.

A clinical and educational telemedicine link between Bulgaria and Greece.

During its transition to a market economy, Bulgaria benefited from foreign aid provided by Greece. One of the projects was the clinical and educational telemedicine link between the Medical University of Varna in Bulgaria and the Faculty of Medicine of Aristotle University of Thessaloniki in Greece. This began in 1997. In terms of the educational activities, the Bulgarian side of the network supports: an electronic classroom equipped with personal workstations, multimedia projectors and videoconference facilities; electronic design and publishing activities; Web hosting and mail server activities; and satellite communications. Communications are via ISDN. The main clinical experience has been remote consultations in immunology. This experience (admittedly limited) demonstrates that telemedicine can be used to provide assistance to remote colleagues. In addition, the use of telemedicine can greatly improve the quality of care available to travellers and migrant workers in cases where the patient cannot communicate with the attending physician because of a language barrier.

Developing prison telemedicine systems: the Greek experience.

Prison telemedicine systems operate in circumstances in which the provision of medical care is very expensive. In 1999 the Greek Ministry of Justice decided to use telemedicine to improve health services in the largest prison in Greece (Korydallos Prison, in Athens). The Nikea Hospital in Piraeus undertook to support the effort in order: to enable prison paramedics and guards to call for remote evaluation of inmates when the prison's doctors were off duty; to provide second opinions; and to allow screening and primary care coverage for inmates through teleconsultations with Nikea Hospital specialists. For 12 months following installation, intensive 'hands-on' training on the use of the system was offered to the staff of both the Korydallos Prison and the Nikea Hospital. In all, 400 physicians, nurses and paramedics were trained. Despite all this effort, there were serious operational problems related either to prison bureaucracy or to the inflexibility of the Greek national health system, which annulled the effectiveness of the prison telemedicine system. The experience suggests that prison telemedicine is a viable option if freed from bureaucratic and labour-related obstacles, and can improve the quality of care available to prisoners.