Primary graft dysfunction (PGD) is a life-threatening complication among heart transplant recipients and a major cause of early mortality. Although the pathogenesis of PGD is still unclear, ischemia/reperfusion injury has been identified as a predominant factor. Both necrosis and apoptosis contribute to the loss of cardiomyocytes during ischemia/reperfusion injury, and this loss of cells can ultimately lead to PGD. The aim of our prospective study was to find out whether cell death, necrosis and apoptosis markers present in the donor myocardium can predict PGD. The prospective study involved 64 consecutive patients who underwent orthotopic heart transplantation at our institute between September 2010 and January 2013. High-sensitive cardiac troponin T (hs-cTnT) as a marker of minor myocardial necrosis was detected from arterial blood samples before the donor’s pericardium was opened. Apoptosis (caspase-3, active + pro-caspase-3, bcl-2, TUNEL) was assessed from bioptic samples taken from the right ventricle prior graft harvesting. In our study, 14 % of transplant recipients developed PGD classified according to the standardized definition proposed by the ISHLT Working Group. We did not find differences between the groups in regard to hs-cTnT serum levels. The mean hs-cTnT value for the PGD group was 57.4±22.9 ng/l, compared to 68.4±10.8 ng/l in the group without PGD. The presence and severity of apoptosis in grafted hearts did not differ between grafts without PGD and hearts that subsequently developed PGD. In conclusion, our findings did not demonstrate any association between measured myocardial cell death, necrosis or apoptosis markers in donor myocardium and PGD in allograft recipients. More detailed investigations of cell death signaling pathways in transplanted hearts are required., O. Szarszoi, J. Besik, M. Smetana, J. Maly, M. Urban, J. Maluskova, A. Lodererova, L. Hoskova, Z. Tucanova, J. Pirk, I. Netuka., and Obsahuje bibliografii
Pneumatic tourniquets are widely used in pediatric extremity surgery to provide a bloodless field and facilitate dissection. This prospective study was carried out to examine possible effect of different anesthesia techniques on oxidative stress and endothelial dysfunction connected with ischemia-reperfusion injury during extremity operations at children's age. Patients were randomized into three groups of 15 patients each: general inhalational anesthesia with sevoflurane (group S), total intravenous anesthesia with propofol (group T) and regional anesthesia (group R). Venous blood samples for determination of the malondialdehyde in plasma and erythrocytes, protein carbonyl groups concentration as well as plasma nitrites and nitrates level and xanthine oxidase activity were obtained at four time points: be fore peripheral nerve block and induction of general anesthesia (baseline), 1 min before tourniquet release, 5 and 20 min after tourniquet release. This study demonstrates that total intravenous anesthesia with propofol and regional anesthesia techniques provide better antioxidant defense and reduce endothelial dysfunct ion than general inhalational anesthesia with sevoflurane during tourniquet application in pediatric extremity surgery., I. Budic ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Hospitalized patients in internal medicine have an increased risk of low physical reserve which further declines during the hospital stay. The diagnosis requires bed-side testing of functional domains or more complex investigations of the muscle mass. Clinically useful biomarkers of functional status are needed, thus we aimed to explore the potential of microRNAs. Among hospitalized patients, we recorded the basic demographics, anthropometrics, nutritional status, and physical function domains: hand-grip strength (HGS, abnormal values M<30 kg, W<20 kg), balance (<30 s), chair-stands speed (CHSS<0.5/s) and gait speed (GS<0.8 m/s). A panel of five micro-RNAs (miRNA 1, miRNA 133a, miRNA 133b, miRNA 29a, miRNA 29b) and basic blood biochemistry and vitamin D values were recorded. We enrolled 80 patients (M40, W40), with a mean age of 68.8± 8.4 years. Obesity was observed in 27.5 % and 30 %, low HGS and low CHSS in 65.0, 77.5 %, and 80, 90 % of men and women respectively. The median hospital stay was 6.5 days. MiRNA29a and miRNA29b have the strongest correlation with the triceps skinfold (miRNA 29b, r=0.377, p=0.0006) and CHSS (miRNA 29a, r=0.262, p=0.02). MiRNA 29a, miRNA 29b and 133a levels were significantly higher in patients with CHSS<0.5/s. Other anthropometric parameters, mobility domains, or vitamin D did not correlate. All miRNAs except of miRNA 1, could predict low CHSS (miRNA29b, AUROC=0.736 CI 0.56-0.91, p=0.01), particularly in patients with low HGS (miRNA 29b, AUROC=0.928 CI 0.83-0.98). Among hospitalized patients in internal medicine, low functional status was frequent. MicroRNAs were fair biomarkers of the antigravity domain, but not other domains. Larger studies with clinical endpoints are needed., Petra Vrbová, Simona Valášková, Andrea Gažová, Juraj Smaha, Martin Kužma, Ján Kyselovič, Juraj Payer, Tomáš Koller., and Obsahuje bibliografii
Roztroušená skleróza je chronické onemocnění centrálního nervového systému neznámé etiologie s projevy autoimunitního zánětu a neurodegenerace. Onemocnění je heterogenní s nepředvídatelnou prognózou. Průběh choroby lze monitorovat klinickými parametry a sledováním vývoje patologických změn na magnetické rezonanci. I když máme znalosti o efektu nově zaváděných léků na základě klinických studií, není možné předvídat jejich účinnost u konkrétního pacienta. Proto se v posledních letech prosazuje snaha najít takové laboratorní markery, které by co možná nejspolehlivěji odpověděly na otázky spojené se subklinickou aktivitou onemocnění, jeho progresí a usnadnily terapeutické rozhodnutí na základě personifikované medicíny., Multiple sclerosis is a chronic disease of the central nervous system of unknown etiology with manifestations of autoimmune inflammation and neurodegeneration. The disease is heterogeneous with an unpredictable outcome. The course of the disease can be monitored with clinical parameters as well as pathological changes on magnetic resonance imaging. Even though the effects of newly introduced drugs are known from clinical trials, it is not possible to predict their efficacy in a specific patient. Therefore, efforts have intensified over the recent years to identify laboratory markers that would as reliably as possible answer questions on subclinical disease activity, its progression and would facilitate therapeutic decisions based personalized medicine. Key words. multiple sclerosis – therapy – biomarkers The author declare he has no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE “uniform requirements” for biomedical papers., and J. Piťha
The safety of pedestrians and cyclists in traffic is justified especially in terms of prevention. This paper deals with the biomechanical analysis of load exerted on the child pedestrian and cyclist. In the case of cyclists, the impact configurations were chosen with respect to the statistical outputs (sudden enter the road or the case of non-giving way; the car front vs. the left side of the cyclists). Two tests were performed in the same configuration and nominal collision speed, the first one with a bicycle helmet and the second one without the helmet. The initial position of pedestrian was chosen with respect to the dummy degrees of freedom. Using the accelerometers in the head, chest, pelvis and knee of the dummy acceleration fields were detected, which are the child pedestrian and cyclist exposed during the primary and secondary collision. In addition, prediction diagnostics method implementation was discussed such as one possible solution of vulnerable road users harm reduction. In conclusion, the results are interpreted by values of biomechanical load and severity of potential injuries including kinematic and dynamic comparison.
The present article introduces a novel method of characterizing the macromechanical cartilage properties based on dynamic testing. The proposed approach of instrumented impact testing shows the possibility of more detailed investigation of the acting dynamic forces and corresponding deformations within the wide range of strain rates and loads, including the unloading part of stress-strain curves and hysteresis loops. The presented results of the unconfined compression testing of both the native joint cartilage tissues and potential substitute materials outlined the opportunity to measure the dissipation energy and thus to identify the initial mechanical deterioration symptoms and to introduce a better definition of material damage. Based on the analysis of measured specimen deformation, the intact and pathologically changed cartilage tissue can be distinguished and the differences revealed., F. Varga, M. Držík, M. Handl, J. Chlpík, P. Kos, E. Filová, M. Rampichová, A. Nečas, T. Trč, E. Amler., and Obsahuje bibliografii
Biomechanics has widely expanded in the last decades. The last development of computers provides new possibilities in this field. Problems can be solved faster and can be more extensive. One of these problems is the biomechanical model of human body. Its realisaton is practically impossible without using computers, because it is necessary to solve systems of thousands of equations.
There are several software packages that enable human body modeling. One of them is the PAM environment [15] developed by the ESI Group International. This computational system is based on the Finite Element Method and is one of the mostly used systems for crash test simulations.
Various human body models for various purposes are developed. Pregnant female model serve to optimize safety systems in cars to be more friendly to pregnant abdomen. and Obsahuje seznam literatury
The presented work is focused on the biomechanical study of the dental disk implant. The first part of the study deals with the strain analysis of the affected bone tissue and the dental implant loaded in the coronoapical direction by force 190 N. The study includes three types of implant anchorge, four degrees (stages) of osseointegration and nine degrees describing the quality of the cancellous bone. Two types of the disk implant were researched: single-disk and double-disk implant. Biomechanical study of the implant was focused on a stress-strain analysis of the affected bone rissue. The highest influence on the stresses in the bone tissue was primarily an implant anchorage. By the application of correlation relationships between Young modulus and the apparent density of the bone tissue - which is measurable in patients - we achieved the variable presented in this study. and Obsahuje seznam literatury
The presented work follows the first part [1], which is focused on the analysis of bone tissue in terms of dependence of bone tissue 'quality' and its subsequent behaviour based on the stress around the disk implant when biting.
This second part is focused on the stress-strain analysis (and tolerability) of disk implants as loaded during the masticating process.
The study includes two types of disk implants (single-disk and double-disk), three types of anchorage, four degrees (stages) of osseointegration in three quality degrees of the cancellous bone. The study, as expected, has shown that the problematic area of he implants is a transition between the implant body and the disk component, where the equivalent stress in the analyzed implants reaches 700 MPa. and Obsahuje seznam literatury
Orthopaedists in the Czech Republic use corrective braces of type Cheneau or Cerny for conservative treatment of non skeletal scoliosis. The brace has force effects on a child spine and if it is used for enough long time the spine defect is corrected. The brace is made individually for each patient in this way: first, the negative plaster form of a child trunk and then the positive plaster form are made. The positive plaster form is deepened in the places where brace has to push on the patient trunk. The laminate brace made according to this plaster form pushes the child trunk like a tight shoe principle. The paper shows the manner of determination and computer algorithms for solving of the stress state in vertebrae and inter-vertebrae discs and the spinal curve correction under brace force effects for a concrete child patient. The pathologic spinal curve deformities are measured on the X-ray of patient. The spine stress state and spine deformation correction are solved as a beam (spine) on an elastic ground (soft tissue). There are used two algorithms. The 1st algorithm solves the spine stress state and deformation under brace force effect given by displacements of trunk surface. The 2nd algorithm has as input the spinal curves of a patient with and without brace measured on the X-rays. The difference of the two curves is the spine deformity corretions and the spine stress state and necessary trunk surface displacement are the results. If the ideal spine curve is set as the curve under brace effect then the trunk surface is equal to the optimal brace form. The calculation algorithm and parameters ware verified with treatment courses. The trunk surface load was checked by sensor plates which ware put into braces to measure the load values between the brace and the child trunk surface. and Obsahuje seznam literatury