bluuebunny/crossref_metadata_2025 huggingface dataset:
Melatonin prevents lipid peroxidation in human erythrocytes but augments deterioration of deformability after in vitro oxidative stress
Authors: Dikmenoglu Neslihan , Ileri Esin , Seringec Nurten , Ercil Dilek
Published: December 2019

Oxidative stress decreases the deformability of erythrocytes. Anti-oxidant measures may alleviate, pro-oxidative damage may augment this decrease. Melatonin is reported to exert both anti-oxidant and pro-oxidant properties on erythrocytes. The aim of the present study was to evaluate the effects of melatonin on erythrocyte deformability under oxidative stress conditions induced by the combination of hydrogen peroxide (20 mM) and sodium azide (100 μM). Erythrocyte suspensions were incubated for 10 min with melatonin (1–1000 μM) prior to oxidative stress. Erythrocyte deformability was measured by Laser-assisted Optical Rotational Cell Analyzer (LORCA). Lipid peroxidation was determined via malondialdehyde (MDA) measurements by HPLC. Melatonin alone did not change erythrocyte deformability. Oxidative stress alone decreased the deformability of erythrocytes by 25.8±3.1% (P<0.05). Melatonin pre-treatment augmented the decrease in erythrocyte deformability but prevented lipid peroxidation. Melatonin (1 μM) did not cause any additional effect on erythrocyte deformability. Higher concentrations (10–1000 μM) further decreased deformability (P<0.05). Erythrocytes exposed to oxidative stress had MDA levels of 116.3±14.3 μmol/g Hb. Melatonin (1 μM) slightly increased MDA levels, but 1000 μM melatonin reduced it by 35% (P<0.05). These findings indicate that melatonin exerts antioxidant effect on lipids. Deterioration of erythrocyte deformability may be due to a separate pro-oxidative action on proteins.
Contrast-enhanced ultrasound versus conventional ultrasound and MS-CT in the diagnosis of abdominal aortic dissection
Authors: Clevert D.-A. , Horng A. , Clevert D.-A. , Jung E.M. , Sommer W.H. , Reiser M.
Published: December 2019

Purpose: To evaluate the diagnostic results of different ultrasound techniques: B-scan, color-coded Doppler sonography (CCDS) and contrast-enhanced ultrasound in the diagnosis of abdominal aortic dissection in comparison to multislice computed tomography (MS-CT).

Materials and methods: Between March 2006 and December 2008, 35 patients (28 males, 7 females) with a mean age of 58 years (range 37–87 years) with abdominal aortic dissection and 15 patients (11 males, 4 females) with a mean age of 53 years (range 42–78 years) without abdominal aortic dissection as a control group were examined with B-scan, CCDS and contrast-enhanced ultrasound (CEUS) after injection of 1.0–1.2 cc of SonoVue (Bracco, Italy). The examinations were performed using a Sequoia 512 (Siemens/Acuson, Mountain View) system with CPS software. Standardized MS-CTA using a 16 or 64 row scanner (Somatom Sensation 16 or 64, Siemens Medical Systems, Forchheim, Germany) served as the reference standard.

Results: The sensitivity of B-scan and CCDS for detecting abdominal aortic dissections were both 23/35 (68%); for contrast-enhanced ultrasound it was 34/35 (97%). Dissection membrane, differentiation of true and false lumen and flow direction within the true and false lumen were better detected by CEUS than by CCDS. The lack of angle dependence of the US probe and lack of flow and pulsations artifacts in CEUS made the examination procedure easier. All findings were confirmed by MS-CT.

Conclusion: With contrast-enhanced ultrasound, diagnostic accuracy sensitivity and specificity for the diagnosis of abdominal aortic dissections is improved as compared to B-scan and CCDS. Dissection membrane and flow within the true and false lumen are clearly differentiated by CEUS. Thus CEUS is a promising alternative for patients whose condition does not allow an examination by CTA.
Shear resistance of human umbilical endothelial cells on different materials covered with or without extracellular matrix: Controlled in-vitro study
Authors: Hoepken S. , Fuhrmann R. , Jung F. , Franke R.P.
Published: December 2019

A variety of medical grade polymeric materials are used in tissue engineering and biomedical technology. Dense non-porous polymeric foils were used as substrates for endothelial cell layers. Half a the test samples (polymers and control materials) were seeded with bovine corneal endothelial cells (BCEC) which more or less covered the substrates with an extracellular matrix (ECM) in the consecutive culturing period. Afterwards the ECM covered as well as the uncovered materials were seeded with human umbilical venous endothelial cells (HUVEC). HUVEC seeded samples were cultured either under static or under dynamical conditions in a cone/plate rheometer with a mean low arterial shear stress of 8.2 dyn/cm2 to simulate the flow conditions in a coronary vein graft.

With the exemption of polyvinyl chloride all other materials could be coated with ECM at least partially. Under static conditions the best results with respect to complete coverage with ECM and HUVEC were seen on polyester and polyurethane. Under shear load, however, the complete HUVEC layer together with the ECM detached from the polymer surface within a short time. ECM and HUVEC remained no longer than 43 minutes on anyone of the materials tested. The materials as supplied and tested were clearly not appropriate as implants in contact to the flowing blood.
Comparative efficiency and hemorheological consequences of hemotransfusion and epoetin therapy in anemic cancer patients
Authors: Muravyov A.V. , Cheporov S.V. , Kislov N.V. , Bulaeva S.V. , Maimistova A.A.
Published: December 2019

The aim of our study was to compare hemorheological consequences of hemotransfusion and recombinant human erythropoetin treatment in anemic cancer patients. Forty anemic patients with solid nonmyeloid malignancies were enrolled in this prospective, open-label study. Both prior to and following treatment (epoetin beta, 10,000 units subcutaneously thrice weekly, for four weeks and transfusion of 400 ml of erythrocyte mass) hemorheological measurements including blood and plasma viscosity, hematocrit (Hct), hemoglobin, red blood cell aggregation (RBCA) and deformability were completed. It was found an increase of Hb from 76.07±3.68 g/l to 87.86±4.26 g/l after the transfusion. It was accompanied by Hct rise by 25% (from 23.67±1.85 to 29.50±1.96%, p<0.05). Under these conditions the whole blood viscosity (BV) was increased by 19% (p<0.05). Plasma viscosity did not change markedly. Therefore the main cause of the whole blood viscosity rise was an increase of Hct. After erythrocyte mass transfusion there were some increases of red cell deformability and aggregation (by 7%, p>0.05). Under these conditions the Hct/BV ratio as an index of oxygen transport efficiency was changed after transfusion only slightly. While after four weeks of epoetin treatment the hematocrit/viscosity ratio was raised by 14% (p<0.05), in spite of the high blood viscosity. In addition RBCA decreased (p<0.01) and their deformability was increased by 14% (p<0.05). In vitro microrheological data permit to suggest that epoetin has a direct effect on the microrheological properties of red cells due to activation of the cellular signal transduction system including the tyrosine kinases and phosphatases. Thus, Epoetin beta administered s.c. thrice weekly, during four weeks, increased hemoglobin levels, improved hemorheological profile and especially its microrheological part as well as the blood transport capacity in anemic cancer patients who were receiving chemotherapy and its hemorheological effect was more positive than under hemotransfusion.
In vitro hemorheological effects of red wine and alcohol-free red wine extract
Authors: Rabai M. , Toth A. , Kenyeres P. , Mark L. , Marton Zs. , Juricskay I. , Toth K. , Czopf L.
Published: December 2019

The French paradox is based on epidemiological evidence which supports that moderate red wine consumption reduces the risk of cardiovascular diseases. A number of experimental animal studies reported favourable cardiovascular effects of alcohol-free red wine extract (AFRW). Our study was designed to determine red wine and AFRW induced changes in various hemorheological parameters. These effects may play a role in the pathophysiology of the French paradox regarding the cardiovascular protective impacts of red wine. Blood samples of healthy volunteers were mixed with red wine to achieve alcohol concentrations of 1‰, 3‰ and 10‰, respectively, with equivalent amount of AFRW or physiological saline. Blood samples were pretreated with red wine or AFRW in order to prove the protective effects on erythrocytes from impairment of deformability caused by the free radical generator phenazine methosulfate (PMS). Erythrocyte aggregation (Myrenne and LORCA), deformability (LORCA) and platelet aggregation (Carat TX4) were measured. Erythrocyte aggregation using Myrenne aggregometer was inhibited by red wine and AFRW compared to the saline treated samples. The difference reached already significance at 1‰ concentration at the AFRW samples (p < 0.05). Furthermore, red wine caused stronger inhibition than AFRW. The difference between the two agents became significant at 10‰ concentration (p < 0.05). LORCA aggregation index and threshold shear rate supported these results at the highest concentration. Erythrocyte deformability of healthy volunteers did not change significantly for any concentrations of red wine and AFRW. On the other hand AFRW at 3‰ concentration significantly prevented erythrocytes from impairment of deformability caused by PMS (p < 0.05). Platelet aggregation was significantly inhibited by the highest concentration of AFRW (p < 0.05). Our results show that red wine and AFRW have some beneficial effects on hemorheological parameters that may contribute to the French paradox.
Viscosity of human bile sampled from the common bile duct
Authors: Reinhart Walter H. , Näf Gabriela , Werth Baseli
Published: December 2019

Cholestasis is a frequent gastroenterological problem, which is tackled by endoscopic procedures. Little is known about bile viscosity, a major determinant of its flow. We measured the viscosity of bile from the common bile duct during endoscopic retrograde cholangiography. Bile was aspirated immediately after cannulation of the papilla and deep-frozen. Viscosity was measured with a rotational viscometer at 37°C and a broad range of shear rates (0.08–69.5 s−1). The majority of the 138 patients (64.5%) had bile viscosities between water (0.7 mPa.s) and the lower limit of plasma (1.1 mPa.s). In 20 patients (14.5%) it was above that of plasma (>1.4 mPa.s), and showed a non-Newtonian behaviour, i.e. the viscosity increased exponentially with decreasing shear rate. Cholecystectomized patients had a lower bile viscosity. Bile viscosities did not differ between patient groups with either choledocholithiasis, sludge, cholangitis, biliary pancreatitis, pancreatic carcinoma, or cholangiocarcinoma. We conclude that bile viscosity in the common bile duct is usually lower than that of plasma, in 15% it is higher and increases exponentially with decreasing flow rate, which may lead to a vicious cycle.
Sex-dependent differences in rheological properties and the relation of blood viscosity to erythrocyte aggregation indices among morbidly obese patients
Authors: Wiewióra Maciej , Sosada Krystyn , Slowinska Ludmila , Piecuch Jerzy , Glück Marek , Zurawinski Wojciech , Turczynski Bolesław
Published: December 2019

Some studies indicate that obesity is associated with rheological disturbances. Because there are usually sex differences in the type of obesity we decided to evaluate rheological differences between male and female obese patients. We studied 18 morbidly obese men, mean age 43.66 ± 11.32 years, mean body mass index (BMI) 49.82 ± 6.03 kg/m2 and 20 obese females, mean age 40.6 ± 11.86 years, mean BMI 47.41 ± 8.81 kg/m2. Blood and plasma viscosity measurements were performed using a cone-plate viscometer (Brookfield DV-II). Erythrocyte elongation and red blood cell (RBC) aggregation were measured using the Laser-assisted Optical Rotational Cell Analyser (LORCA). Whole blood viscosity and RBC deformability expressed by the elongation index were significantly higher in obese men. We did not observe differences in plasma viscosity, corrected blood viscosity and aggregation parameters among the obese population. Blood viscosity correlated with selected RBC aggregation indices. We conclude that morbidly obese patients presented sex-dependent differences in some rheological properties. This study indicates a relation between erythrocyte aggregation indices and blood viscosity in obese populations.
Slow flow of passive neutrophils and sequestered nucleus into micropipette
Authors: Kaleridis V. , Athanassiou G. , Deligianni D. , Missirlis Y.
Published: December 2019

In the present study, the role of the nucleus and its contribution to the deformability of the passive neutrophils was investigated. To determine the rheological properties of the nucleus and of the neutrophil itself, deformation tests on single neutrophil and sequestered nucleus have been performed by micropipette under low aspiration pressure (80 Pa = 2–3 Pcr). The stiffness of the nucleus was found to be larger than that of the neutrophil, and its viscosity was found almost ten-fold higher. A subpopulation of neutrophils (Sub-A) showed two phases of deformation, a first rapid phase and a second phase with a constant deformation rate up to their full entrance, with an apparent viscosity μapp-second-Phase(NSub-A) = 286 ± 123 Pa·s, calculated by the liquid drop model. Another subpopulation (Sub-B) of the tested neutrophils displayed three deformation phases: a first one reflecting the rapid entry of cell into the micropipette, a second with constant deformation rate, and a third phase, with a slower, also constant, deformation rate were recorded. The corresponding apparent viscosities were found as μapp-second-Phase(NSub-B) = 341 ± 94 Pa·s and μapp-third-Phase(NSub-B) = 1651 ± 734 Pa·s. The apparent viscosity values of the neutrophilic nucleus, μapp (Nnucl) = 2468 ± 1345 Pa·s and of the whole neutrophil calculated in the third phase of deformation, μapp-third-Phase(NSub-B) = 1651 ± 734 Pa·s were comparable. These results support our hypothesis that the nucleus plays a significant role in the mechanical and rheological behavior of the neutrophil, especially when it has to pass through openings much smaller than its size.
Dynamic contrast-enhanced MRI as a valuable non-invasive tool to evaluate tissue perfusion of free flaps: Preliminary results
Authors: Fellner Claudia , Jung Ernst M. , Prantl Lukas
Published: December 2019

Early detection of a compromised circulation of free flaps and an immediate revision may lead to higher rates of flap salvage. The aim of this study was to evaluate the perfusion of the entire flap using dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI). DCE was performed in 11 patients after flap transplantation using an optimized 3D gradient echo sequence to cover the whole flap. The percentage increase of signal intensity over time was evaluated for the free flap as well as for a reference tissue. Furthermore, normalized signal increase was calculated as the ratio of signal increase within the flaps to the signal increase in the reference tissue. Signal increase in free flaps and reference tissue was compared using the Wilcoxon-test (p < 0.05), normalized signal increase in normally perfused (n = 9) and in flaps with compromised perfusion (n = 2) using Mann-Whitney-test (p < 0.05). Signal increase within normally perfused flaps was similar to the reference tissue. In flaps with compromised perfusion the increase was significantly lower than in reference tissue. Normalized signal increase in adequately perfused flaps and flaps with compromised perfusion also showed a significant difference. DCE MRI may be a valuable non-invasive tool to evaluate tissue perfusion of the complete free flap.
Characterization of microvascularization of liver tumor lesions with high resolution linear ultrasound and contrast enhanced ultrasound (CEUS) during surgery: First results
Authors: Jung E.M. , Ross C.J. , Rennert J. , Scherer M.N. , Farkas S. , von Breitenbuch P. , Schnitzbauer A.A. , Piso P. , Lamby P. , Menzel C. , Schreyer A.G. , Feuerbach S. , Schlitt H.J. , Loss M.
Published: December 2019

Aim: Evaluation of high resolution linear ultrasound and intra-operative linear contrast enhanced ultrasound (CEUS) and its benefit for the detection and characterization of tumor lesions. Material and methods: Twenty patients were investigated preoperatively regarding tumor detection using CT (n = 8) or MRI (n = 12) and image fusion (VNav) (n = 3). All patients had surgery for their hepatic tumor (hepatocellular carcinoma (HCC), cholangiocellular carcinoma (CCC), metastasis, and adenoma). Ultrasound was performed intra-operatively first with B-scan using a convex probe. Than multifrequency linear transmitters (6–9 MHz, 6–15 MHz, LOGIQ E9, GE) were applied for B-scan, coulor coded Doppler sonography (CCDS) and Power Doppler followed by dynamic CEUS with Contrast Harmonic Imaging (CHI) after bolus injection of a maximum of 15 mL SonoVue®. Results: In 9 cases with the use of intra-operative CEUS additional tumor lesions (diameter 4–15 mm) could be detected and were histologically confirmed after surgical resection (7 cases) or intra-operative biopsy (2 cases). Using intraoperative CEUS 64 tumor lesions could be detected compared to 51 tumor lesions detected by preoperative CT or MRI (p < 0.05). Using the 6–15 MHz multifrequency linear transducer with CHI, arterial perfusion of adenomas, neuroendocrine metastases and HCC lesions was detectable. In 3 cases a resection was not achievable. Two of these cases were treated with radio frequency ablation (RFA). The other case had no curable option due to multifocal tumor manifestation. Conclusion: The intra-operative use of high-resolution linear transducer techniques with CEUS offers new diagnostic perspectives for an effective liver surgery.
ARFI-based tissue elasticity quantification in comparison to histology for the diagnosis of renal transplant fibrosis
Authors: Stock K.F. , Klein B.S. , Vo Cong M.T. , Sarkar O. , Römisch M. , Regenbogen C. , Büttner M. , Schuster T. , Matevossian E. , Amann K. , Clevert D.A. , Heemann U. , Küchle C.
Published: December 2019

Background and purpose: Until recently clinical diagnosis of chronic renal allograft dysfunction could only be established invasively by renal biopsy. Given the risks of that procedure, a non-invasive, diagnostic test would be very advantageous. Novel ultrasound-based elasticity tools, using “Acoustic Radiation Force Impulse (ARFI)” technology are now available. Previously this technique has been utilised to quantify liver fibrosis. First results of these studies are promising. The purpose of our study was to investigate correlation between stiffness values obtained by ARFI-quantification and histological fibrosis score in renal transplants. Methods: We employed “Virtual Touch™ tissue quantification” (Siemens Acuson, S2000) to quantitatively measure tissue stiffness in the cortex of transplant kidneys. Eighteen patients were included in this prospective study, recording close temporal ARFI-quantification and fibrosis measurements. All patients undergoing renal transplant biopsy were examined with ARFI-quantification (15 measurements per transplant kidney). Resistive indices were also calculated from pulsed-wave Doppler ultrasound. Transplant biopsies were histologically evaluated by a reference nephropathologist and graded according to the percentage of fibrosis and to the BANFF-score. Due to the non-normal distribution of the data the Spearman-correlation-coefficient (rho) was used to assess the bivariate relationship of ARFI and fibrosis in the transplant kidney. Results: There was a significant positive moderate correlation between mean ARFI-values and the grade of fibrosis (rho = +0.465; p = 0.026). This correlation was also valid for the mean ARFI-values and the BANFF-category (rho = +0.468; p = 0.025). There was no significant correlation between the mean ARFI-values and the resistive indices in the transplant kidney (rho = +0.034; p = 0.904). Nevertheless, a positive correlation between the mean RI-values of the kidney and the grade of fibrosis was established (rho = +0.563; p = 0.015). Conclusion: The mean values of ARFI measurements and the resistive indices are potentially independent explanation variables for evaluating the grade of fibrosis in transplant kidneys.
Role of genetic polymorphisms in myocardial infarction at young age
Authors: Incalcaterra E. , Caruso M. , Balistreri C.R. , Candore G. , Lo Presti R. , Hoffmann E. , Caimi G.
Published: December 2019

Acute myocardial infarction (AMI) in young adult presents a typical pattern of risk factors, clinical, angiographic and prognostic characteristics. In the last years we demonstrated that hemorheological profile is altered in these patients in a persistent way and independently of the number of risk factors and of the extent of coronary lesions. Thus, the hyperviscosity syndrome following AMI could be considered an intrinsic characteristic of these patients. Consequently it is possible to hypothesise the presence of a genetic background at the origin of this predisposition. If this background is able to influence the risk of ischemic heart disease, this should be particularly evident in young subjects. Since inflammatory mechanisms play a central role in mediating all phases of atherosclerosis, genes encoding for inflammatory or anti-inflammatory molecules are candidates for the risk of developing atherosclerosis. As atherosclerosis is the first cause of mortality in Western countries and if pro-inflammatory genotypes contribute to risk of coronary heart disease, alleles associated to disease susceptibility should not be included in the genetic background favouring longevity: People genetically predisposed to a weak inflammatory activity have fewer chances to develop cardiovascular disease and, therefore, have better chance for a long-life. According to this hypothesis, we studied in our population of young patients with AMI, the distribution of some polymorphisms influencing a inflammation and found an higher prevalence of pro-inflammatory polymorphisms (SNP A2080G of pyrin gene, SNP Gly670Arg of PECAM gene, C1019T of Cx 37 gene, SNP G1059C of PCR gene) and a lower prevalence of anti-inflammatory polymorphisms (Asp299Gly of TLR4 gene, SNP –1082 G/A of IL10 gene, CCR5Δ32). Results of these studies show that early myocardial infarction could be associated with a genetic predisposition to an intense inflammatory response, associated also to an hyperviscosity syndrome.
Effect of strenuous physical exercise on circulating cell-derived microparticles
Authors: Chaar Vicky , Romana Marc , Tripette Julien , Broquere Cédric , Huisse Marie-Geneviève , Hue Olivier , Hardy-Dessources Marie-Dominique , Connes Philippe
Published: December 2019

Strenuous exercise is associated with an inflammatory response involving the activation of several types of blood cells. In order to document the specific activation of these cell types, we studied the effect of three maximal exercise tests conducted to exhaustion on the quantitative and qualitative pattern of circulating cell-derived microparticles and inflammatory molecules in healthy subjects. This study mainly indicated that the plasma concentration of microparticles from platelets and polymorphonuclear neutrophils (PMN) was increased immediately after the strenuous exercise. In addition, the increase in plasma concentration of microparticles from PMN and platelets was still observed after 2 hours of recovery. A similar pattern was observed for the IL-6 plasma level. In contrast, no change was observed for either soluble selectins or plasma concentration of microparticles from red blood cells, monocytes and endothelial cells. In agreement, sVCAM-1 and sICAM-1 levels were not changed by the exercise. We conclude that a strenuous exercise is accompanied by platelet- and PMN-derived microparticle production that probably reflects the activation of these two cell types.
Homocysteine levels and the metabolic syndrome in a Mediterranean population: A case-control study
Authors: Vayá Amparo , Carmona Pilar , Badia Natalia , Pérez Rafael , Hernandez Mijares Antonio , Corella Dolores
Published: December 2019

Hyperhomocysteinemia (HH) and metabolic syndrome (MS) are associated with increased cardiovascular risk. However, whether there is a link between MS or its components and homocysteine levels in a population without cardiovascular disease is not well established. We conducted a case-control study in 61 MS patients (41 males, 20 females, aged 51 ± 11 years) and in 98 controls without MS (59 males, 39 females, aged 50 ± 10 years) to ascertain the association between MS and HH, and with inflammatory markers. MS was classified according to the updated ATPIII criteria [17]. No differences in homocysteine levels were observed when comparing MS patients and controls (12.0 ± 3.18 μM vs. 11.9 ± 3.5 μM, p = 0.829). No association was found between HH (homocysteine >15 μM) and MS, its components (abdominal obesity (p = 0.635), hypertension (0.229), low-HDL cholesterol (p = 0.491), glucose >100 mg/dL (0.485), hypertriglyceridemia (p = 0.490)) or the number of MS components (p = 272). When considering glucose >110 mg/dL (NCEP-ATPIII criteria, 2001) instead of glucose intolerancen >100 mg/dl (updated ATPIII criteria, Grundy, 2005), a borderline association with HH was observed (p = 0.054) of statistical significance (p = 0.008) when glucose >126 mg/dL was considered. In a multivariate regression model, creatinine, folic acid and vitamin B12 were the only independent predictors of homocysteine levels (p < 0.05). Although MS correlated with inflammatory parameters (fibrinogen, hs-RCP, plasma viscosity and leukocyte count, p < 0.001), no association was found between HH and the above-mentioned parameters (p > 0.05). Our results do not indicate a link between SM or its individual components with HH, and diabetes was the only relevant contribution. Cardiovascular disease risk due to MS and HH seems to share no common mechanisms.
Treatment strategies for prevention of cardioembolic stroke in atrial fibrillation
Authors: Park Jai-Wun , Leithäuser Boris , Rittger Harald , Brachmann Johannes
Published: December 2019

Stroke is the third leading cause of mortality and is one of the leading cause of disability in the world today. Although underused, anticoagulation with warfarin is still the treatment of choice for prevention of stroke in patients with AF, though hemorrhage is clearly increased in the anticoagulated patient. The substantial difficulties associated with warfarin use give reasons for the continuing challenge of decision making about antithrombotic therapy. They have led to a search for alternative approaches of stroke prophylaxis resulting in a strategy of mechanically sealing the left atrial appendage (LAA) and excluding it from the systemic circulation. A couple of years ago a percutaneous transcatheter transseptal approach to LAA occlusion has become feasible. Since then, valuable technical knowledge and a proof of concept emerged from clinical trials using three different systems. However, also the intervention bears a risk. Thus, identifying those patients who gain the most from either therapy is crucial which, in the first line, means to calculate the risk of stroke or bleeding. Unfortunately, patients with some defined comorbidities are at risk of both, cerebral embolism or hemorrhage. Whether this target group may benefit from LAA occlusion is a matter of this discussion.
High-dose atorvastatin treatment in patients with peripheral arterial disease: Effects on platelet aggregation, blood rheology and plasma homocysteine
Authors: van der Loo Bernd , Spring Silviana , Koppensteiner Renate
Published: December 2019

Background: Statins are used for the treatment of hypercholesterolemia. Although they are well known to have pleiotropic effects, their dose-dependent influence on platelet aggregation, hemorheologic properties and the plasma levels of homocysteine in patients with peripheral arterial disease (PAD) has not been thoroughly investigated so far. Methods and results: From a total of 100 patients with PAD 48 patients were randomized to a treatment with atorvastatin 80 mg/d for six months, and 52 patients served as controls who continued their medication including statins in lower doses. At baseline and at six months' follow up we assessed platelet aggregation upon stimulation with ADP, collagen and epinephrine using light transmission aggregometry. Furthermore, we determined major hemorheologic variables as well as the plasma levels of homocysteine, folic acid, and vitamin B6 and B12. No patient had obtained folic acid or B vitamin supplement. Platelet aggregation upon agonist-induced stimulation did not differ between patients under high-dose atorvastatin therapy and controls at baseline and after six months (p > 0.05). All hemorheologic parameters (plasma viscosity, red cell aggregation, whole blood viscosity, hematocrit, platelets, leucocytes) measured at baseline and after six months were not significantly different between both groups, too. After therapy with 80 mg atorvastatin homocysteine levels were significantly elevated as compared with baseline values (p = 0.0007), whereas levels remained unchanged in the control group. Folic acid levels were higher in the patients receiving high-dose atorvastatin as compared with controls both at baseline (p = 0.002) and at six months' follow up (p = 0.034). No significant difference in vitamin B6 and B12 levels both at baseline and after six months could be detected in either group. Conclusions: Treatment with 80 mg atorvastatin did not affect platelet aggregation and major hemorheologic parameters. The finding of an increase of homocysteine plasma levels in the presence of rather elevated levels of folic acid needs further investigation.
Relationships between insulin sensitivity measured with the oral minimal model and blood rheology
Authors: Brun Jean-Frédéric , Varlet-Marie Emmanuelle , Raynaud de Mauverger Eric
Published: December 2019

In studies using the intravenous glucose tolerance test with minimal model analysis we reported that low insulin sensitivity (SI) is associated with increased erythrocyte aggregability and plasma viscosity, that appeared to be markers of insulin resistance. Recently, development of modelling has made available a new approach of insulin sensitivity from oral glucose tolerance test data (oral minimal model). We aimed at determining in 111 subjects (51 men, 62 women, age 11–77 yr), insulin sensitivity with this approach together with blood viscosity parameters. With this approach the Myrenne indexes of red cell aggregation were negatively correlated to SI (M; r = −0.456; p = 0.0007; M1; r = −0.397; p = 0.004) while plasma viscosity was not. Correlations with fasting insulin levels (Ib) were weaker (M; r = 0.2711; p = 0.05; M1; r = 0.373; p = 0.007). Accordingly, a stepwise regression analysis selects M as the best correlate of SI and M1 as the best correlate of Ib. With this approach plasma viscosity does not exhibit any clear relationship with SI. This study supports the concept that RBC hyperaggregability is the prominent hemorheologic symptom of insulin resistance.
Cell-specific regulation of acetylcholinesterase expression under inflammatory conditions
Authors: de Oliveira P. , Gomes A.Q. , Pacheco T.R. , Vitorino de Almeida V. , Saldanha C. , Calado A.
Published: December 2019

Acetylcholine (ACh) has been shown to exert an anti-inflammatory function by down-modulating the expression of pro-inflammatory cytokines. Its availability can be regulated at different levels, namely at its synthesis and degradation steps. Accordingly, the expression of acetylcholinesterase (AChE), the enzyme responsible for ACh hydrolysis, has been observed to be modulated in inflammation. To further address the mechanisms underlying this effect, we aimed here at characterizing AChE expression in distinct cellular types pivotal to the inflammatory response. This study was performed in the human acute leukaemia monocytyc cell line, THP-1, in human monocyte-derived primary macrophages and in human umbilical cord vein endothelial cells (HUVEC). In order to subject these cells to inflammatory conditions, THP-1 and macrophage were treated with lipopolysaccharide (LPS) from E.coli and HUVEC were stimulated with the tumour necrosis factor α (TNF-α). Our results showed that although AChE expression was generally up-regulated at the mRNA level under inflammatory conditions, distinct AChE protein expression profiles were surprisingly observed among the distinct cellular types studied. Altogether, these results argue for the existence of cell specific mechanisms that regulate the expression of acetylcholinesterase in inflammation.
Automated method for tracking vasomotion of intravital microvascular and microlymphatic vessels
Authors: Sheng You-Ming , Xiu Rui-Juan
Published: December 2019

Dynamic tracking of microvascular and microlymphatic vasomotion presents a critical image processing technique in the evaluation of function and dysfunction of the microvasculature. Many methods for determination of diameter changes have been reported. Previous methods which were specifically developed for vasomotion tracking of intravital, fluorescence-free, rapidly constricting microvascular and microlymphatic vessels have various limitations due to complex image background, vessel wall distortion, image drift, noise and other artifacts. In order to overcome these major obstacles and remove undesirable limitations, this study proposed a tracking strategy based on feature matching of moving object—VasTrack. First, we calculate the image drift vector by feature template matching of a landmark in the background. Second, dynamically regulate the position of a sample line in accordance with the drift vector for sustaining the consistency of measurement location. Third, dynamically recognize and track edge position changes by applying feature template matching using edge context. This method does not require special preprocessing of video image registration and rotation. VasTrack compensates efficiently for image drift and vessel wall distortion, can simultaneously track and determine vessel diameters at any orientation and in multiple locations. Testing proved that VasTrack is robust and accurate, and will satisfy the needs of basic microcirculatory research and clinical inspection.
Homocysteine levels in morbidly obese patients. Its association with waist circumference and insulin resistance
Authors: Vayá Amparo , Rivera Leonor , Hernández-Mijares Antonio , de la Fuente Miguel , Solá Eva , Romagnoli Marco , Alis R. , Laiz Begoña
Published: December 2019

The association between morbid obesity and hyperhomocysteinemia (HH) remains controversial and the nature of this relationship needs to be clarified as several metabolic, lipidic, inflammatory and anthropometric alterations that accompany morbid obesity may be involved. In 66 morbidly obese patients, 47 women and 19 men aged 41 ± 12 years and 66 normo-weight subjects, 43 women and 23 men, aged 45 ± 11 years, we determined homocysteine (Hcy) levels along with lipidic, anthropometric, inflammatory and insulin resistance markers. In addition, we investigated the effect of Metabolic Syndrome (MS) and its components on Hcy levels. Obese patients had statistically higher Hcy levels than controls: 12.76 ± 5.30 μM vs. 10.67 ± 2.50 μM; p = 0.006. Moreover, morbidly obese subjects showed higher waist circumference, glucose, insulin, HOMA, leptin, triglycerides, fibrinogen, C reactive protein (CRP) (p < 0.001, respectively), and lower vitamin B12 (p = 0.002), folic acid and HDL-cholesterol (p < 0.001, respectively). In the multivariate regression analysis, waist circumference, glucose, leptin and folic acid levels were independent predictors for Hcy values (p < 0.050). When obese patients were classified as having MS or not, no differences in Hcy levels were found between the two groups (p = 0.752). Yet when we analysed separately each MS component, only abdominal obesity was associated with Hcy levels (p = 0.031). Moreover when considering glucose >110 mg/dL (NCEP-ATPIII criteria) instead of glucose intolerance >100 mg/dl (updated ATPIII criteria), it also was associated with HH (p = 0.042). These results were confirmed in the logistic regression analysis where abdominal obesity and glucose >115 mg/dL constitute independent predictors for HH (OR = 3.2; CI: 1.23–13.2; p = 0.032, OR: 4.6; CI: 1.7–22.2; p = 0.016, respectively). The results of our study indicate that increased Hcy levels are related mostly with abdominal obesity and with insulin resistance. Thus, HH may raise atherothrombotic and thromboembolic risk in these patients.
Plasma viscosity levels in pulmonary thromboembolism
Authors: Atici Atilla Guven , Kayhan Servet , Aydin Davut , Yilmaz Yasemin Ari
Published: December 2019

Genetic and acquired thrombophilic risk factors may play role on developing venous thromboembolism (VTE). In many cases of pulmonary thromboembolism (PE) it can not be defined any explicit risk factor. In this study we aimed to identify the role of plasma viscosity level on PE. The investigation was planned prospectively and 33 patients with PE and 36 apparently healthy and nonsmoker volunteers as control group were enrolled in the study. The mean plasma viscosity levels were determined in patients with PE and in healthy volunteers as 1.42 ± 0.30 cP and 1.29 ± 0.22 cP respectively. The mean plasma viscosity levels was found to be different between PE and healthy group (p = 0.009). The mean levels of triglyceride, fibrinogen and hematocrit were found different between patients with PE and control group (p < 0.05). Variables including sex, age, smoking habits, levels of hematocrit, fibrinogen, total cholesterol and triglyceride were not associated with plasma viscosity values in patients with PE. Plasma viscosity levels were found higher in patients with PE compared with healthy indivudials. But it is needed to further studies to define the interactions between factors effecting blood rheology and development of thrombosis.
Moderate red wine consumption improves hemorheological parameters in healthy volunteers
Authors: Toth A. , Sandor B. , Papp J. , Rabai M. , Botor D. , Horvath Zs. , Kenyeres P. , Juricskay I. , Toth K. , Czopf L.
Published: December 2019

Pieces of epidemiological evidence have supported that moderate red wine consumption reduces the risk of cardiovascular diseases (French-paradox). Our previous in vitro experiment has demonstrated favourable hemorheological effects of red wine, alcohol-free red wine extract and ethanol. Thirty-nine healthy, non-smoking male volunteers between 18–40 years were assigned into two groups: control group had drunk water, while red wine group had consumed 2 dl of red wine each day at dinner for 3 weeks. No alcohol had been drunk for one week prior to the study. Blood was obtained in the morning of the first and last day. Hematocrit (Hct), plasma (PV) and whole blood viscosity (WBV) (Hevimet 40 capillary viscometer), red blood cell (RBC) aggregation (Myrenne and LORCA aggregometer) and deformability (LORCA ektacytometer) were measured and Hct/WBV ratio was calculated to determine oxygen carrying capacity. Hct was adjusted to 40%. Hct and PV were not affected. WBV remained unchanged in controls, but it considerably decreased in the red wine group compared to the 3-week control group, while Hct/WBV ratio became significantly higher in the red wine group compared to the control (p < 0.05). RBC aggregation significantly decreased in the red wine group and became significantly lower compared to the 3-week controls (p < 0.05). Red wine significantly increased RBC deformability (p < 0.05) at high shear stress. Our results show that moderate red wine consumption has beneficial effects on hemorheological parameters which may contribute to the French-paradox.
Hemorheological changes caused by lead exposure
Authors: Kim C.B. , Shin Sehyun , Song Seok-Heung
Published: December 2019

Lead is a ubiquitous, biohazardous, and toxic heavy metal that induces a broad range of physiological, biochemical, and behavioral dysfunctions. We investigated the effect of lead on hemorheological characteristics, including deformability and aggregation. We found that red blood cell (RBC) deformability was unaffected at low concentrations of lead-rich plasma, but showed a significant decrease at high concentrations even within 1 h of incubation. In addition, apparent alterations in RBC aggregation were observed with an increase in lead concentration and incubation time. These results highlight the influence of lead on hemorheology and microcirculation.
Weak König’s Lemma Implies the Uniform Continuity Theorem
Authors: Diener Hannes
Published: December 2019

As the title suggests we are going to show that Weak König’s Lemma implies the uniform continuity theorem; to be more precise the uniform continuity theorem for functions $[0,1] \to \R$ . This improves upon a result by J. Berger who has proven this implication for functions $[0,1] \to \N$ .
L1-Computability, Layerwise Computability and Solovay Reducibility
Authors: Miyabe Kenshi
Published: December 2019

We propose a hierarchy of classes of functions that corresponds to the hierarchy of randomness notions. Each class of functions converges at the corresponding random points. We give various characterizations of the classes, that is, characterizations via integral tests, L1-computability and layerwise computability. Furthermore, the relation among these classes is formulated using a version of Solovay reducibility for lower semicomputable functions.
Computably Categorical Fields via Fermat’s Last Theorem
Authors: Miller Russell , Schoutens Hans
Published: December 2019

We construct a computable, computably categorical field of infinite transcendence degree over the rational numbers, using the Fermat polynomials and assorted results from algebraic geometry. We also show that this field has an intrinsically computable (infinite) transcendence basis.
On Some Computability Notions for Real Functions
Authors: Skordev Dimiter
Published: December 2019

A computability notion for real functions which is in Grzegorczyk’s spirit is shown to be equivalent to one in the spirit of Tent and Ziegler under some general assumptions.
Problem Behavior and Developmental Tasks in Adolescents with Visual Impairment and Sighted Peers
Authors: Pfeiffer Jens P. , Pinquart Martin
Published: December 2019

This longitudinal study analyzed associations of problem behavior with the attainment of developmental tasks in 133 adolescents with visual impairment and 449 sighted peers. Higher levels of initial problem behavior predicted less progress in the attainment of developmental tasks at the one-year follow-up only in sighted adolescents. This association was significantly more negative in sighted adolescents than in adolescents with visual impairment. In addition, we found that a higher initial attainment of developmental tasks was associated with lower levels of problem behavior at follow-up only in the sighted group. Only adolescents with visual impairment who experienced a setback (losing a romantic partner) showed an increase in problem behavior. Therefore, this group needs more support when facing setbacks.
Pubertal Development, Body Satisfaction, and Desired Body Changes Gender Differences in Early Adolescence
Authors: Watzlawik Meike
Published: December 2019

Physical changes that occur during puberty alter the body image. Girls formerly had more difficulties accepting physical changes than boys. In this longitudinal study (three family visits; time interval: 1 year), pubertal development, body satisfaction, and desired body changes of 106 boys and 108 girls were assessed. The adolescents were between 10 and 12 years of age at the time of the first visit. We examined whether—with progressing pubertal development—a stronger increase in body dissatisfaction could still be found for girls than for boys. This was questioned because of the changing male ideal of beauty. Results show that girls are still more often dissatisfied with their bodies and that their body satisfaction even decreases significantly over time. Only by the time of the second interview did gender differences in desired body changes become significant, showing that boys and girls both have certain idealistic visions of how they would like to look. These ideals seem to be more fed by peer-group comparisons than by comparing oneself to the existing ideals of beauty. Nevertheless, girls are still more negatively affected by societal norms than boys. For girls alone, pubertal status predicts body satisfaction and the wish for bodily changes. For boys, other predictors seem to be crucial.
A Longitudinal Study of Perceptual Grouping by Proximity, Luminance and Shape in Infants at Two, Four and Six Months
Authors: Farran Emily K. , Brown Janice H. , Cole Victoria L. , Houston-Price Carmel , Karmiloff-Smith Annette
Published: December 2019

Grouping by luminance and shape similarity has previously been demonstrated in neonates and at 4 months, respectively. By contrast, grouping by proximity has hitherto not been investigated in infancy. This is also the first study to chart the developmental emergence of perceptual grouping longitudinally. Sixty-one infants were presented with a matrix of local stimuli grouped horizontally or vertically by luminance, shape or proximity at 2, 4, and 6 months. Infants were exposed to each set of stimuli for three presentation durations. Grouping was demonstrated for luminance similarity at the earliest testing age, 2 months, by shape similarity at 4 months, but was not observed for grouping by proximity. Grouping by shape similarity showed a distinctive pattern of grouping ability across exposure durations, which reflected familiarity preferences followed by novelty preferences. This remained stable across age. No link was found between the emergence of perceptual grouping ability and the exposure duration required to elicit grouping. We conclude by stressing the importance of longitudinal studies of infant development in furthering our understanding of human cognition, rather than relying on assumptions from the adult endstate.
Collecting, exploring and sharing personal data: Why, how and where
Authors: Estrada-Galiñanes Vero , Wac Katarzyna
Published: November 2019

New, multi-channel personal data sources (like heart rate, sleep patterns, travel patterns, or social activities) are enabled by ever increased availability of miniaturised technologies embedded within smartphones and wearables. These data sources enable personal self-management of lifestyle choices (e.g., exercise, move to a bike-friendly area) and, on a large scale, scientific discoveries to improve health and quality of life. However, there are no simple and reliable ways for individuals to securely collect, explore and share these sources. Additionally, much data is also wasted, especially when the technology provider ceases to exist, leaving the users without any opportunity to retrieve own datasets from “dead” devices or systems. Our research reveals evidence of what we term human data bleeding and offers guidance on how to address current issues by reasoning upon five core aspects, namely technological, financial, legal, institutional and cultural factors. To this end, we present preliminary specifications of an open platform for personal data storage and quality of life research. The Open Health Archive (OHA) is a platform that would support individual, community and societal needs by facilitating collecting, exploring and sharing personal health and QoL data.