Experimentally based numerical models and numerical simulation with parameter identification of human lumbar FSUs in traction

Numerical simulation of the behaviour of human lumbar spine segments, moreover, parameter-identification of the component organs of human lumbar FSUs are presented in traction therapies, by using FEM analysis. First, a simple 2D model, than a refined 2D model, and finally a refined 3D model were applied for modeling lumbar FSUs. For global numerical simulation of traction therapies the material constants of component organs have been obtained from the international literature. For local parameter identification of the component organs, an interval of the possible material moduli has been considered for each organ, and the possible combinations of real moduli were obtained, controlling the process by the measured global deformations. In this way, the efficiency of conservative traction therapies can be improved by offering new experimental tensile material parameters for the international spine research

Apixaban and risk of myocardial infarction: meta-analysis of randomized controlled trials

The coagulation system contributes greatly to the evolution of myocardial infarction (MI). Anticoagulation may reduce the occurrence of MI as monotherapy or with con- comitant use of aspirin. Activated factor X antagonists (anti- Xa) and direct thrombin inhibitors have promising results in various indications in non-inferiority trials. However, results regarding their cardiovascular safety are heterogeneous. We systematically evaluated the risk of MI and mortality in patients receiving the new-generation oral anti-Xa agent apixaban. Electronic databases were searched to find pro- spective, randomized, controlled clinical trials (RCT) that evaluated the clinical impact of apixaban. Efficacy measures included frequency of MI, cardiovascular and overall mor- tality. Outcome parameters of RCTs were pooled with a ran- dom-effects model. Between January 2000 and December 2013, 12 RCTs comprising 54,054 patients were identified. Based on the pooled results, there was no increase in the risk of MI in patients treated with apixaban [odds ratio (OR) 0.90;95 % confidence interval (CI) 0.77–1.05; p = 0.17] com- pared to different controls. Cardiovascular and overall mor- tality with apixaban was comparable to the control groups (OR 0.88; 95 % CI 0.72–1.06; p = 0.18, OR 0.89; 95 % CI 0.77–1.03; p = 0.11, respectively). The pooled risk of major bleeding was lower in the apixaban treated groups (OR 0.84; 95 % CI 0.62–1.12; p = 0.23) however this reached signifi- cant level only in subgroup analysis of trials with anticoagu- lant regimes in the control (OR 0.66; 95 % CI 0.51–0.87; p = 0.003). In a broad spectrum of patients and compared to different controls apixaban treatment was not associated with an increase in MI or mortality

Autóipari termelő vállalat gyártási folyamatának optimalizálása lean eszközökkel = Optimization of automotive industry's manufacturing process with lean tools

Lean plays i mportant role in industrial environment. Automotive industries use lean tools in order to reduce cost and i mprove productivity. To achieve the company's objectives and so lve the detected problems I also used lean tools. By using lean tools we want to decrease total process cost (TPC). In order to achieve this target, the three-shift production has to reduce in two-shift production, which result decrease in the human resource costs and production costs. In order to reduce shifts we have to increase overall equipment efficiency (OEE) and eliminate minimum 50% of wastes by implementing 5s methodology, using Poka-yoke and scheduled maintenance.A lean szemléletű gyártás jelentős szerepet játszik az ipari környezetben, eszközeit napi tevékenységként használják az autóiparban árcsökkentés és termelékenység javítása céljából. A kutatásomban részt vevő nyugatdunántúli autóipari termelő vállalat detektált problémáinak megoldására kitűzött célok elérése érdekében lean eszközöket alkalmaztam, amelyekkel a folyamat teljes átfutási költségének csökkenését kívánjuk elérni. Ennek eléréshez műszakcsökkentést tűztünk ki célul, amely által emberi erőforrás- és előállítási költség megtakarí tás válik lehetővé, csökkentve a teljes folyamat átfutási költségét. A műszakcsökkentést a gépek teljes körű hatékonyságának (OEE) növelésével kívánjuk elérni, amely érték növeléséhez a veszteségek minimum 50%-os csökkentése szükséges. Ezt a célt az 5s módszer bevezetésével, Poka-yoke használatával valamint az 5s fejlesztés harmadik lépésénél bevezetett karbantartásokkal kívánunk elérni

Novel Mechanisms of Sildenafil in Pulmonary Hypertension Involving Cytokines/Chemokines, MAP Kinases and Akt

Pulmonary arterial hypertension (PH) is associated with high mortality due to right ventricular failure and hypoxia, therefore to understand the mechanism by which pulmonary vascular remodeling initiates these processes is very important. We used a well-characterized monocrotaline (MCT)-induced rat PH model, and analyzed lung morphology, expression of cytokines, mitogen-activated protein kinase (MAPK) phosphorylation, and phosphatidylinositol 3-kinase-Akt (PI-3k-Akt) pathway and nuclear factor (NF)-κB activation in order to elucidate the mechanisms by which sildenafil's protective effect in PH is exerted. Besides its protective effect on lung morphology, sildenafil suppressed multiple cytokines involved in neutrophil and mononuclear cells recruitment including cytokine-induced neutrophil chemoattractant (CINC)-1, CINC-2α/β, tissue inhibitor of metalloproteinase (TIMP)-1, interleukin (IL)-1α, lipopolysaccharide induced CXC chemokine (LIX), monokine induced by gamma interferon (MIG), macrophage inflammatory protein (MIP)-1α, and MIP-3α. NF-κB activation and phosphorylation were also attenuated by sildenafil. Furthermore, sildenafil reduced extracellular signal-regulated kinase (ERK)1/2 and p38 MAPK activation while enhanced activation of the cytoprotective Akt pathway in PH. These data suggest a beneficial effect of sildenafil on inflammatory and kinase signaling mechanisms that substantially contribute to its protective effects, and may have potential implications in designing future therapeutic strategies in the treatment of pulmonary hypertension

Effect of inulin supplementation and age on growth performance and digestive physiological parameters in weaned rabbits

[EN] Three diets were formulated, a control diet (C, 40.7% NDF, 15.1% CP), the same diet but medicated (M, 500 mg/kg oxytetracycline and 50 mg/kg thiamulin), and a third diet obtained substituting 4% of barley with inulin (Frutafi t) in C diet (I). Pannon White does and their litters were randomly allocated into three groups (8/group) at 21 d of lactation and diets offered to the does and kids from 21 d of lactation onwards. After weaning (28 d), growing rabbits (30 cages/ treatment, 2 rabbits/cage) were fed the same diet as before weaning. At 28, 35 and 42 d of age, 6 healthy animals from each group (1 animal/cage) were slaughtered. Live body weight, feed intake and feed conversion ratio increased and growth rate decreased with age (P<0.001). Feed intake decreased in rabbits fed I diet compared to those fed M diet (by 11%, P<0.05), with those fed C diet showing an intermediate value. Growth rate from 28 to 35 d of age was not affected by diets, but decreased from 36 to 42 d in rabbits fed I diet compared to those fed C and M diets (P<0.05), with no effect on feed conversion ratio. Inulin did not affect mortality, which was low (¿ 3.3%), but increased morbidity compared to C and M diets (11.7 vs. 2.5%, P<0.05). Diets did not affect caecal weight, pH, cellulase and pectinase activity or microbial counts. Inulin diet decreased caecal xylanase activity (P<0.05) compared to C and M diets, reduced propionic and butyric acid and increased acetic acid concentration compared to M diet, whereas C diet showed intermediate values. Caecal pH and counts of E. coli and total aerobic bacteria increased and pectinase activity decreased (P<0.05) at 35 d of age (compared to 28 and 42 d of age). The number of the strictly anaerobic bacteria decreased and cellulase and xylanase activity increased (P<0.05) at 42 d of age compared to 28 and 35 d. Propionic acid concentration decreased with age from 28 to 42 d (P<0.05) but VFA concentration and acetic and butyric acids proportions did not change. In conclusion, the inclusion of 4% of inulin in the diet of weanling rabbits showed no positive effect.The research was funded by the OTKA (project No. T046999) and the TéT foundation (project No. FR27/2007).The authors are grateful to Dr. L. Maertens (ILVO-Belgium) for his advice on diet formulation.Bónai, A.; Szendró, Z.; Matics, Z.; Fébel, H.; Kametler, L.; Tornyos, G.; Horn, P.... (2010). Effect of inulin supplementation and age on growth performance and digestive physiological parameters in weaned rabbits. World Rabbit Science. 18(3). https://doi.org/10.4995/wrs.2010.588318

A lumbális gerinc kísérleti és numerikus biomechanikai vizsgálata = Experimental and numerical biomechanical analysis of lumbar spine

A lumbális gerinc kísérleti és numerikus biomechanikai vizsgálata. I. Elkészítettük a lumbális gerinc-szegmentumok nemlineáris, nemsima finomított végeselemes modelljét, és elvégeztük a nyújtási terápia numerikus szimulációját egészséges és degenerált szegmentumon. Numerikusan szimuláltuk a porckorong tönkremeneteli folyamatait, a súlyfürdő tehermentesítő hatását, a porckorongot alkotó szervek tehermentesülését a kezelés során. Elvégeztük a gerinc stabilitásvizsgálatának katasztrófaelméleti modellezését is. II. Osteoporotikus lumbális gerinc-csigolyák CT felvételei és mechanikai törésvizsgálata alapján összefüggést állítottunk fel a csigolyák csontszerkezeti paraméterei és nyomószilárdsági jellemzői között. Meghatároztuk a szilárdsági jellemzők csigolyamagasság menti változását is. Javaslatot tettünk a nők csigolyáinak öregedés során tapasztalható nemlineáris szilárdságcsökkenésének modellezésre. III. In vitro kísérleti eredmények alapján következtettünk a porckorong helyén a csigolyák közé műtéttel beépített kétféle távtartó esetén a távtartók azonnali stabilizáló hatására különböző fiziológiai terhelések esetén. IV. Elvégeztük a merev fúzióval és a különféle távtartóval stabilizált gerinc működésének in vivo laboratóriumi mozgáselemzését, a különféle betegcsoportok gerincének mozgásképességét összehasonlítva az egészségesekéivel. Létrehoztuk az egészséges kontrollcsoport és az utánkövetéses betegek alapméréseinek adatbázisát. | Experimental and numerical biomechanical analysis of the lumbar spine I. Finite element numerical simulation of hydrotraction treatment of human lumbar spine was executed based on nonlinear, nonsmooth FE model of the lumbar spinal segments with healthy and degenerated intervertebral discs. Degeneration processes of discs were followed numerically. The unloading effect of the hydrotraction therapy was numerically demonstrated for each of the component organs of the FSU. The spinal stability was modeled by catastrophe theory method as well. II. Relation was obtained between the vertebral morphometry based on CT pictures and the compression load bearing capacity, energy absorption capacity, ductility of osteoporotic vertebrae, based on compressive loading tests. Regional compressive strength parameters were determined along the height of vertebrae. Mathematical model was created for the nonlinear age-related compressive strength decrease for vertebrae of women. III. Analyzing the results of in vitro experiments, the immediate stabilization effects of different surgical methods and applied cages were analyzed under physiologic loading of the spine. IV. Laboratory motion analysis of spine stabilized by rigid fusion and different cages was executed, related to different groups of patients, by comparing the mobility of healthy and operated patients. Data bases of the healthy control group and the long term follow up groups were created

Subsequent effect of subacute T-2 toxicosis on spermatozoa, seminal plasma and testosterone production in rabbits

Pannon White (n512) male rabbits (weight: 4050 to 4500 g, age: 9 months) received 2ml of a suspension containing purified T-2 toxin by gavage for 3 days. The daily toxin intake was 4 mg/animal (0.78 to 0.99 mg/kg body weight (BW)). Control animals (n512) received toxin-free suspension for 3 days. Since a feed-refusal effect was observed on the second day after T-2 administration, a group of bucks (n510) were kept as controls (no toxin treatment) but on a restricted feeding schedule, that is, the same amount of feed was provided to them as was consumed by the exposed animals. On day 51 of the experiment (i.e. 48 days after the 3-day toxin treatment), semen was collected, and pH, concentration, motility and morphology of the spermatozoa, as well as concentration of citric acid, zinc and fructose in the seminal plasma, were measured. After gonadotropinreleasing hormone (GnRH) analogue treatment, the testosterone level was examined. One day of T-2 toxin treatment dramatically decreased voluntary feed intake (by 27% compared to control, P,0.05) and remained lower ( P,0.05) during the first 2 weeks after the withdrawal of the toxin. BW of the contaminated rabbits decreased by 88% on days 17 and 29 compared to controls ( P,0.05). No effect of toxin treatment was detected on pH and quantity of the semen or concentration of spermatozoa. The ratio of spermatozoa showing progressive forward motility decreased from 65% to 53% in the semen samples of toxin-treated animals compared to controls ( P.0.05). The ratio of spermatozoa with abnormal morphology increased ( P,0.05) in the ejaculates collected from the toxin-treated animals. T-2 toxin applied in high doses decreased the concentration of citric acid in seminal plasma ( P,0.05). No effect of T-2 toxin on the concentrations of the other seminal plasma parameters (fructose and zinc) was observed. T-2 toxin decreased the basic testosterone level by 45% compared to control ( P,0.01) and resulted in lower ( P,0.05) GnRH-induced testosterone concentration. Feed restriction, that is, less nutrient intake, resulted in more morphologically abnormal spermatozoa in the semen, but it did not cause significant loss in BW, motility of the spermatozoa, composition of the seminal plasma or testosterone concentration – its effect needs further examination