Clinical Hemorheology and Microcirculation - Volume 75, issue 1

Authors: Jung, Friedrich | Connes, Philippe | Lehmann, Christian

Article Type: Editorial

DOI: 10.3233/CH-209100

Citation: Clinical Hemorheology and Microcirculation, vol. 75, no. 1, pp. 1-2, 2020

Authors: Küpper, J.-H. | Jung, F. | Krieger, V. | Hufert, F.

Article Type: Letter

DOI: 10.3233/CH-209008

Citation: Clinical Hemorheology and Microcirculation, vol. 75, no. 1, pp. 3-5, 2020

Authors: Jung, F. | Krüger-Genge, A. | Franke, R.P. | Hufert, F. | Küpper, J.-H.

Article Type: Short Communication

Abstract: There is growing evidence that COVID-19 not only affects the lungs but beyond that the endothelial system. Recent studies showed that this can lead to microcirculatory impairments and in consequence to functional disorders of all inner organs. The combination of endothelial dysfunction with a generalized inflammatory state and complement elements may together contribute to the overall pro-coagulative state described in COVID-19 patients leading to venular as well as to arteriolar occlusions.

Keywords: COVID-19, endocytosis, endothelial cell dysfunction, endotheliitis

DOI: 10.3233/CH-209007

Citation: Clinical Hemorheology and Microcirculation, vol. 75, no. 1, pp. 7-11, 2020

Authors: Jung, F. | Krieger, V. | Hufert, F.T. | Küpper, J.-H.

Article Type: Research Article

Abstract: Some months ago, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) broke out in Wuhan, China, and spread rapidly around the world. Some states, such as the Netherlands, Germany, Great Britain, Sweden and the USA initially focused on keeping the restrictions for economy and society as low as possible. The responsible authorities were of the opinion - and still are e.g. in Sweden - that it is sufficient enough to protect particularly vulnerable persons such as the elderly or people with pre-existing conditions. The idea behind this is that as soon as 60 to 70 percent of the population is infected …with a pathogen, a so-called “herd immunity” has developed. However, the increasing numbers of deaths and modelling studies showed the expected overload of the hospitals. Therefore, most countries decided for a temporary lockdown with the exception of Sweden. Based on the number of the total population, three times more people died from COVID-19 in Sweden (2679 deaths per 10 million inhabitants) compared to Germany (6848 deaths per 80 million inhabitants). The comparison Sweden versus Taiwan is even worse because 1072 times more people died in Sweden based on the number of the population (6 deaths per 24 million inhabitants). In the face of the lack of an antiviral treatment and the lack of a protective vaccine one must state Taiwan has made the best out of the pandemic situation whereas Sweden failed completely. Show more

Keywords: COVID-19, strategy, Sweden, Taiwan, Germany

DOI: 10.3233/CH-209006

Citation: Clinical Hemorheology and Microcirculation, vol. 75, no. 1, pp. 13-17, 2020

Authors: Jung, E.M. | Stroszczynski, C. | Jung, F.

Article Type: Research Article

Abstract: AIM: Use of contrast enhanced ultrasound (CEUS) in severe cases of COVID-19 infection to assess pulmonary changes near the pleura. MATERIAL AND METHODS: Bedside examinations by an experienced intensive care unit examiner using a multi-frequency probe (C1-6 MHz) with B-mode and CEUS to assess pleural-near changes in severe cases of COVID-19 infection with respiratory failure. CEUS with bolus delivery via a central venous catheter of 2.4 ml Sulphur hexafluoride microbubbles from the arterial phase (10–15 s) to the late phase of 5 min. Digital storage of cine sequences of the lung sound with abdomen for independent assessment with the subsequently performed contrast-enhanced …dual-source CT. RESULTS: In 11 intubated and ventilated patients (arithmetic mean 62 years, 48 to 78 years, 3 women) with confirmed severe COVID-19 infections, a peripherally accentuated consolidation with irregular hyperemia was found in the CEUS and also in the CT examination. Of the 5 cases with pulmonary arterial embolisms, signs of right ventricular failure were found. In all cases, using CEUS low perfused areas of the pleura with adjacent hyperemia could be detected, while, with CT segmental contrast medium, gaps with subpleural compressions were found. Interstitial changes near the pleura led to B-lines and to ground glass opacities in the CT. Near the diaphragm a delayed arterial contrast of the liver was observed. In addition, in 2 cases partial atelectasis, in 3 cases marginal pleural effusions were found. CONCLUSION: CEUS opens up new possibilities for bedside monitoring of pleural reactive inflammatory or peripheral thrombus embolism in severe cases of COVID-19 infection. Show more

Keywords: COVID-19 infection, lung- Contrast-enhanced ultrasound (CEUS), pleural affection, peripheral embolic consolidation

DOI: 10.3233/CH-209005

Citation: Clinical Hemorheology and Microcirculation, vol. 75, no. 1, pp. 19-26, 2020

Authors: Martini, Romeo

Article Type: Research Article

Abstract: The burden of pandemic COVID-19 is growing worldwide, as the continuous increases of contagion. Only 10–15% of the entire infected population has the necessity of intensive care unit (ICU) treatments. But, this relatively low rate of patients has absorbed almost the whole availability of ICU during few days, becoming at least in Italy, an emergency for the national health system. In COVID-19 ICU patients massive aggression of lung with severe pulmonary failure, as well as kidney and liver injuries, heart, brain, bowel and spleen damages with lymph nodes necrosis and even cutaneous manifestations have been observed. Moreover, increased levels of …cytokines so-called “cytokines storm (CS), and overt intravascular disseminated coagulation have been also reported. The hypercoagulation and CS would speculate about a microvascular dysfunction. Unfortunately, no specific observations have been performed on microcirculatory dysfunction in COVID-19 patients. Hence the presumed pathophysiological pathways and models about a microvascular involvement can be gathered by sepsis models studies. But despite this lack of evidence, the COVID-19 has emphasized the compelling need for microcirculation monitoring at the bedside in ICU patients. Show more

Keywords: Microcirculation, COVID-19, endothelial dysfunction

DOI: 10.3233/CH-200895

Citation: Clinical Hemorheology and Microcirculation, vol. 75, no. 1, pp. 27-34, 2020

Authors: Li, XiuMei | Li, Jun | Li, Yong | Wang, HongQiao | Yang, JingRu | Mou, Shuang | Zhou, MaoPing | Jiang, CaiYun | Ning, ChunPing

Article Type: Research Article

Abstract: OBJECTIVE: The aim of our study was to evaluate the role of preoperative US, CEUS, and 99m Tc-MIBI scanning with SPECT/CT in localizing diseased parathyroid glands in cases of refractory secondary hyperparathyroidism (SHPT). MATERIAL AND METHODS: Using pathological results as the gold standard, we compared the operative findings with the preoperative localization of each modality in 73 nodules and evaluated the accuracy, and sensitivity of each modality and combinations of the four modalities. RESULTS: The sensitivity of US, CEUS, 99m Tc-MIBI and SPECT/CT was 98.59%, 94.37%, 50.70% and 78.87%, respectively. US had the highest sensitivity of …the four imaging methods and the diagnostic sensitivity of US and CEUS was superior to that of 99m Tc-MIBI (p  < 0.001 and p  < 0.001) and SPECT/CT (p  = 0.001 and p  = 0.012). In addition, we found that the sensitivity of the combination of US with CEUS, US with 99m Tc-MIBI and/or SPECT/CT, CEUS with 99m Tc-MIBI and/or SPECT/CT, US with CEUS and two other imaging modalities (99m Tc-MIBI and/or SPECT/CT) was 98.59%, 100%, 95.77%, and 100%, respectively. CONCLUSIONS: The combination of US with SPECT/CT is the best choice for the comprehensive preoperative localization of glands in refractory SHPT. CEUS can elevate the accuracy of US in differential diagnosis via the interpretation of dynamic microvascular features. Show more

Keywords: Ultrasonography, CEUS, 99mTc-MIBI, SPECT/CT, refractory secondary hyperparathyroidism

DOI: 10.3233/CH-190723

Citation: Clinical Hemorheology and Microcirculation, vol. 75, no. 1, pp. 35-46, 2020

Authors: Ghanem, Souleiman | Lesznyak, Tamas | Fazekas, Laszlo | Tanczos, Bence | Barath, Barbara | Nasser, Maitham | Horvath, Laszlo | Bidiga, Laszlo | Szabo, Balazs | Deak, Adam | Peto, Katalin | Nemeth, Norbert

Article Type: Research Article

Abstract: BACKGROUND: Chronic kidney disease (CKD) models are known to study pathophysiology and various treatment methods. Renal dysfunction could influence erythrocytes through several pathways. However, hemorheological and microcirculatory relation of CKD models are not completely studied yet. OBJECTIVE: To evaluate erythrocyte micro-rheology, microcirculatory and structural compensatory mechanisms in a rat model of CKD. METHODS: Female Sprague-Dawley rats were subjected to nephrectomy group (NG, n  = 6) or sham-operated group (SG, n  = 6). NG rats were subjected to 5/6 nephrectomy in two stages. In SG no intervention was made on kidneys. Hemorheological and hematological measurements were carried out after …each stage, and 5 weeks after the last operation. Histological and microcirculatory studies were done on the remaining kidney and compared with sham rats. RESULTS: Serum creatinine increased in NG (p  = 0.008), accompanied with decrease of red blood cell count (p  = 0.028) and hemoglobin (p  = 0.015). Erythrocyte aggregation parameters slightly increased in NG, while the elongation index didn’t show significant changes. Microcirculation was intact in the remnant kidney of NG. However, in comparison with SG, the diameter of glomeruli increased significantly (p  < 0.01). CONCLUSIONS: Erythrocyte mass was influenced more than micro-rheological properties in this model. The main compensation mechanism was rather structural than at microcirculatory level. Show more

Keywords: Chronic renal failure, hemorheology, hematology, erythrocytes, rat model

DOI: 10.3233/CH-190763

Citation: Clinical Hemorheology and Microcirculation, vol. 75, no. 1, pp. 47-56, 2020

Authors: Jurischka, Christoph | Dinter, Franziska | Efimova, Anastasia | Weiss, Romano | Schiebel, Juliane | Schulz, Christian | Fayziev, Bekzodjon | Schierack, Peter | Fischer, Thomas | Rödiger, Stefan

Article Type: Research Article

Abstract: BACKGROUND: The 3D printing is relevant as a manufacturing technology of functional models for forensic, pharmaceutical and bioanalytical applications such as drug delivery systems, sample preparation and point-of-care tests. OBJECTIVE: Melting behavior and autofluorescence of materials are decisive for optimal printing and applicability of the product which are influenced by varying unknown additives. METHODS: We have produced devices for bioanalytical applications from commercially available thermoplastic polymers using a melt-layer process. We characterized them by differential scanning calorimetry, fluorescence spectroscopy and functional assays (DNA capture assay, model for cell adhesion, bacterial adhesion and biofilm formation test). …RESULTS: From 14 tested colored, transparent and black materials we found only deep black acrylonitrile-butadiene-styrene (ABS) and some black polylactic acid (PLA) useable for fluorescence-based assays, with low autofluorescence only in the short-wave range of 300–400 nm. PLA was suitable for standard bioanalytical purposes due to a glass transition temperature of approximately 60°C, resistance to common laboratory chemicals and easy print processing. For temperature-critical methods, such as hybridization reactions up to 90°C, ABS was better suited. CONCLUSIONS: Autofluorescence was not a disadvantage per se but can also be used as a reference signal in assays. The rapid development of individual protocols for sample processing and analysis required the availability of a material with consistent quality over time. For fluorescence-based assays, the use of commercial standard materials did not seem to meet this requirement. Show more

Keywords: 3D printing, cell adhesion, autofluorescence, polylactic acid, PLA, polyethylene terephthalate glycol, PETG, acrylonitrile-butadiene-styrene, ABS, thermoplastic polyurethane elastomers, TPU, medicine, pharmaceutical

DOI: 10.3233/CH-190713

Citation: Clinical Hemorheology and Microcirculation, vol. 75, no. 1, pp. 57-84, 2020

Authors: Lee, Seahyoung | Ganesan, Ramakrishnan | Krüger-Genge, Anne | Kratz, Karl | Franke, Ralf-Peter | Lendlein, Andreas | Jung, Friedrich

Article Type: Research Article

Abstract: Establishing an endothelial cell (EC) monolayer on top of the blood contacting surface of grafts is considered to be a promising approach for creating a hemocompatible surface. Here we utilized the high affinity interactions between the EC plasma membrane expressed enzyme called endothelin converting enzyme-1 (ECE-1) and its corresponding substrate big Endothelin-1 (bigET-1) to engineer an EC-specific binding surface. Since enzymatic cleavage of substrates require physical interaction between the enzyme and its corresponding substrate, it was hypothesized that a surface with chemically immobilized synthetic bigET-1 will preferentially attract ECs over other types of cells found in vascular system such as …vascular smooth muscle cells (VSMCs). First, the expression of ECE-1 was significantly higher in ECs, and ECs processed synthetic bigET-1 to produce ET-1 in a cell number-dependent manner. Such interaction between ECs and synthetic bigET-1 was also detectible in blood. Next, vinyl-terminated self-assembled monolayers (SAMs) were established, oxidized and activated on a glass substrate as a model to immobilize synthetic bigET-1 via amide bonds. The ECs cultured on the synthetic bigET-1-immobilized surface processed larger amount of synthetic bigET-1 to produce ET-1 compared to VSMCs (102.9±5.13 vs. 9.75±0.74 pg/ml). The number of ECs bound to the synthetic bigET-1-immobilized surface during 1 h of shearing (5dyne/cm2 ) was approximately 3-fold higher than that of VSMCs (46.25±12.61 vs. 15.25±3.69 cells/100×HPF). EC-specific binding of synthetic bigET-1-immobilized surface over a surface modified with collagen, a common substance for cell adhesion, was also observed. The present study demonstrated that using the substrate-enzyme affinity (SEA) of cell type-specific enzyme and its corresponding substrate can be an effective method to engineer a surface preferentially binds specific type of cells. This novel strategy might open a new route toward rapid endothelialization under dynamic conditions supporting the long-term patency of cardiovascular implants. Show more

Keywords: Endothelin converting enzyme-1, big endothelin-1, endothelialization, shear resistance

DOI: 10.3233/CH-190736

Citation: Clinical Hemorheology and Microcirculation, vol. 75, no. 1, pp. 85-98, 2020