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The impact of bilateral subthalamic deep brain stimulation on long-latency event-related potentials.

The analysis of long-latency event-related potentials (ERPs) is of importance in the evaluation of certain cognitive functions and in following their subsequent changes. The aim of the present study was to investigate whether deep brain stimulation (DBS) itself can cause changes in the configuration of the ERPs. Using a standard oddball auditory paradigm, we elicited auditory cognitive ERPs in 23 Parkinsons disease patients (in both DBS-ON and DBS-OFF conditions) and in 14 healthy controls. The P200 and P300 amplitudes and latencies, the motor reaction times and the accuracy of button pressing were compared between the DBS-ON and DBS-OFF states and subsequently correlated with the applied stimulation voltage and disease duration. Comparison of the DBS-ON and DBS-OFF conditions revealed that neither the amplitude nor the latency of the examined ERP components changed significantly. However, the behavioral and attentional aspects (e.g. the accuracy of the button pressing responses to the target signal) definitely improved after the DBS was turned on. Positive correlations were demonstrated between the P300 amplitudes over the central and frontal regions and the optimal stimulation voltage and between the disease duration and P300 latencies over the Cz and Fz sites. In conclusion, our data indicate that DBS may have different impacts on various electrophysiological parameters during the oddball paradigm.

Effects of coronary revascularization with or without cardiopulmonary bypass on plasma levels of asymmetric dimethylarginine

ObjectivesWe measured and compared serum asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), and L-arginine levels in patients undergoing coronary artery revascularization. MethodsTwo groups of patients with coronary artery disease were subjected to coronary artery bypass graft surgery (CABG) with cardiopulmonary bypass (CPB; n=20) or with off-pump CABG surgery (OPCABG; n=21). Blood samples for measurements of ADMA, SDMA, and L-arginine were withdrawn and determined by liquid chromatography–tandem mass spectrometry from the coronary sinus (CS) and from the peripheral vein. ResultsOn the basis of the intraoperative (CS) samples, ADMA levels rose in the CPB group (F=0.416, P<0.685 and F=14.751, P<0.001 for OPCABG and CPB groups, respectively). A similar significant increase of ADMA was observed in the peripheral blood (F=30.738, P<0.001) during CPB, whereas ADMA levels remained unchanged during OPCABG. The time course of L-arginine levels was significantly different in the blood samples from CS (F=3.255, P<0.05), when compared with samples from the peripheral blood (F=3.255, P<0.05). The values of the L-arginine/ADMA ratio were significantly higher in the OPCABG group at baseline and on the first postoperative day compared with the results of the CPB group (178.29±11.56 vs. 136.28±13.72 and 129.43±7.08 vs. 106.8±6.9 for OPCABG and CPB groups, respectively). ConclusionPlasma levels of ADMA, SDMA, L-arginine, and L-arginine/ADMA ratio are reliable and feasible markers of an early ischemia-reperfusion injury. During CPB operation, the plasma concentration of ADMA increased significantly and remained elevated until the first postoperative day due to extensive ischemia-reperfusion injury caused by CPB.

The issue of plasma asymmetric dimethylarginine reference range – A systematic review and meta-analysis

Background Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase, marker and mediator of endothelial dysfunction. Several studies have demonstrated its value in cardiovascular risk stratification and all-cause mortality prediction. The aim was to determine the reference range of plasma ADMA in healthy adults. Methods and results Taking into account the most widely used ADMA measurement methods, only studies using either high performance liquid chromatography (HPLC) -with fluorescence or mass spectrometric detection-, or enzyme-linked immunosorbent assay (ELISA) to quantify plasma ADMA concentrations were enrolled. 66 studies were included in the quantitative analysis (24 using ELISA and 42 using HPLC) reporting a total number of 5528 non-diabetic, non-hypertensive, non-obese adults without any medication (3178 men and 2350 women, 41.6 ± 16.9 years old). The reference range of ADMA (in μmol/l with 95% confidence interval in parenthesis) was 0.34 (0.29–0.38)– 1.10 (0.85–1.35) with a mean of 0.71 (0.57–0.85) (n = 4093) measured by HPLC and 0.25 (0.18–0.31)– 0.92 (0.76–1.09) with a mean of 0.57 (0.48–0.66) (n = 1435) by ELISA. Conclusions Numerous publications suggested that asymmetric dimethylarginine is not only an outstanding tool of disease outcome prediction but also a new potential therapeutic target substance; the reference range provided by this meta-analysis can become of great importance and aid to further investigations. However, developing a standard measurement method would be beneficial to facilitate the clinical usage of ADMA.

Left atrial dysfunction in light-chain cardiac amyloidosis and hypertrophic cardiomyopathy – A comparative three-dimensional speckle-tracking echocardiographic analysis from the MAGYAR-Path Study

INTRODUCTION While cardiac amyloidosis (CA) is a rare systemic disease characterized by extracellular deposition of protein-derived fibrils, hypertrophic cardiomyopathy (HCM) is histopathologically characterized by myocyte hypertrophy and disarray, interstitial fibrosis, and small intramural coronary arteriole dysplasia. The aim of the present study was to compare left atrial (LA) volumetric and functional characteristics between light-chain (AL) CA and HCM by three-dimensional (3D) speckle-tracking echocardiography (STE). METHODS The AL-CA group initially consisted of 17 patients with AL-CA, but one patient was excluded due to inadequate image quality, and so the study population consisted of 16 patients (mean age: 64.0±9.6 years, five men). Their results were compared with data on 20 age-matched HCM patients (mean age: 59.8±5.2 years, 10 men) and on 16 age-matched healthy controls (mean age: 58.2±7.2 years, six men). Complete two-dimensional Doppler echocardiography and 3D-STE were performed in all cases. RESULTS Significantly increased LA volumes were observed in both AL-CA and HCM compared with the control group. Only active atrial emptying fraction was found to be significantly reduced in AL-CA patients compared to controls. Peak global and mean segmental circumferential, longitudinal and area strains showed significant reductions in AL-CA patients compared with controls, but only peak mean segmental longitudinal strain differed significantly between HCM patients and controls. While no differences were demonstrated in global and mean segmental strain at atrial contraction between HCM patients and controls, AL-CA patients showed reductions in certain strain parameters compared to controls and HCM patients. CONCLUSIONS Different patterns of LA functional characteristics were demonstrated in AL-CA and HCM patients by 3D-STE.

Early post-operative thrombosis of the prosthetic mitral valve in patient with heparin-induced thrombocytopenia

Heparin-induced thrombocytopenia (HIT) is one of the most common immune-mediated adverse drug reactions, with frequencies as high as 2-3% for certain groups of post-cardiac surgery patients. We report on an 50-year-old woman with early post-operative thrombosis of the prosthetic mitral valve due to heparin-induced thrombocytopenia. Non-invasive imaging (two-dimensional transesophageal echocardiography; 2D-TEE) allowed the exact localisation of thrombotic masses and revealed the increase of the mean diastolic mitral gradient. The HIT diagnosis was proved by the clinical scoring system, and with the identification of heparin platelet factor 4-induced antibodies. After the withdrawal of LMWH therapy and the start of intravenous lepirudin treatment, the patients medical condition improved continuously. Follow-up echocardiography showed a step-wise decrease in the severity of the mean diastolic mitral valve gradient and a complete resolution of thrombus formations. Perhaps we may remind ourselves that, whilst HIT is one of the most common immune-mediated adverse drug reactions for certain groups of post-cardiac surgery patients, it can be managed successfully. We would also stress the importance of serial 2D-TEE examinations in the early post-operative period.

Psoriasis and oxidative stress

Psoriasis is among the most common dermatological diseases worldwide. Its significance is emphasized by adverse effects on quality of life, caused by chronic pain, physical and psychical disability due to psoriatic plaques. Besides the development of psoriatic arthritis, which often causes permanent joint damage, former studies revealed an increased risk of inflammatory bowel disease, cardiovascular disease and certain types of cancer. Genetic predisposition and oxidative stress caused by exogenous and endogenous factors can contribute to abnormal differentiation and hyperproliferation of keratinocytes, accordingly the development and maintenance of psoriasis. Moreover, excessive oxidative stress can be responsible for the onset of psoriasis complications. After a brief pathophysiological summary the authors discuss the role of oxidative stress in the development of psoriasis and its complications through several well studied biomarkers (asymmetric dimethylarginine, malondialdehyde, superoxide dismutase, catalase). Orv. Hetil., 2016, 157(45), 1781-1785.

Transcutaneous Carbon Dioxide Treatment Affects Heart Rate Variability – A Pilot Study

Background: The aim of this study was to investigate the effects of carbon-dioxide treatment on heart rate variability (HRV) parameters: mean RR interval (RRI), standard deviation of RR intervals (SDNN), root mean square of successive RR differences (RMSSD); and Porta and Guzik indices, as measures of heart rate asymmetry. Materials and Methods: Twenty patients were enrolled (mean±SD, age=59±7.8 years). Measurements were performed before CO2 treatment, at the beginning of treatment, at 15 min of treatment, immediately after and 1 h after the treatment. Results: Significant increase in SDNN was found 1 h after the treatment when compared to that before it (p=0.011). There were no significant changes in other parameters. Conclusion: CO2 treatment can influence the autonomic nervous system identified by SDNN changes. However, larger studies are required to confirm these results.

Cellular Phone Irradiation of the Head Affects Heart Rate Variability Depending on Inspiration/Expiration Ratio

Background: Mobile phones may have harmful health effects and clinical examinations report ambiguous results of exposure concerning neurophysiological and cardiovascular actions. Materials and Methods: This study investigated heart rate asymmetry (HRA) and heart rate variability (HRV) parameters with 1:2 and 1:1 metronome-paced inspiration/expiration ratios during short-term 1,800MHz GSM cellular phone exposure in 20 healthy volunteers. Results: Significant HRA changes by Porta and Guzik indices were not found on exposure compared to sham exposure. Time-domain HRV parameters on exposure showed significant differences at 1:1 paced, but not at 1:2 paced breathing compared to sham exposure. A mild post-exposure effect was observed regarding root mean square of successive RR-differences. Conclusion: The findings reflect persisting acute effects of GSM handset emission on the autonomic nervous system. Exploring its influences on health status and survival needs further studies. Symmetrical breathing can be used as a sensitizing factor in other HRV/HRA analysis studies.

Transcutaneous Carbon Dioxide Treatment Is Capable of Reducing Peripheral Vascular Resistance in Hypertensive Patients

Aim: We aimed to investigate the effects of a single carbon dioxide (CO2) treatment on arterial stiffness by monitoring the changes of aortic pulse-wave velocity (PWV) and aortic augmentation index (AIXao), which are indicators of arterial stiffness. Patients and Methods: PWV and AIXao were measured by an invasively validated oscillometric device. The measurements of stiffness parameters were performed before the CO2 treatment, and at 1, 4 and 8 h after the first treatment. Results: Thirty-one patients were included. No significant changes were found in PWV. AIXao decreased significantly 1 h and 4 h after CO2 treatment compared to baseline values (p=0.034 and p<0.001). AIXao increased 8 h after the CO2 treatment, but remained significantly lower than baseline AIXao values (p=0.016). Conclusion: CO2 treatment is capable of reducing peripheral vascular resistance. We hypothesize that CO2 is not only a temporal vasodilator but is also capable of activating vasodilation pathways.

Urinary Orosomucoid A Potential Marker Of Inflammation In Psoriasis

Background: Psoriasis is one of the most common chronic, life-long dermatologic diseases, which has considerable negative effects on quality of life. Psoriasis is considered as a systemic inflammatory disease, thus acute phase proteins such as C-reactive protein (CRP) and orosomucoid (ORM) have been shown to play a role in its pathophysiology. This study was aimed to compare CRP, serum ORM (se-ORM) and urinary ORM (u-ORM) levels of psoriatic patients to healthy individuals. Methods: 87 psoriatic patients and 41 healthy individuals were enrolled. Simultaneously obtained venous blood and spot urine samples were analysed. High sensitivity CRP and se-ORM levels were determined by routine procedures on automated analyzers. Urinary ORM was measured by a novel automated turbidimetric assay. U-ORM was referred to urinary creatinine (u-ORM/u-CREAT, mg/mmol). Results: Significantly higher hsCRP (p<0.001) and u-ORM/u-CREAT (p=0.001) levels were found among psoriatic patients compared to controls. No significant differences were found between the groups regarding se-ORM levels. HsCRP, se-ORM and u-ORM/u-CREAT levels were significantly higher in patients with severe psoriasis than in mild and moderate cases (p<0.05). Conclusion: As a highly sensitive, easily available biomarker u-ORM shows itself capable of becoming a new inflammatory marker in psoriasis providing clinically useful information on disease severity.