Clinical Hemorheology and Microcirculation - Volume 88, issue s1

Authors: Braune, S. | Krüger-Genge, A. | Jung, F.

Article Type: Editorial

DOI: 10.3233/CH-248110

Citation: Clinical Hemorheology and Microcirculation, vol. 88, no. s1, pp. S1-S1, 2024

Authors: Martin, Frank | Neubert, Annemarie | Lutter, Anne-Helen | Scholka, Jenny | Hentschel, Erik | Richter, Heiko | Anderer, Ursula

Article Type: Research Article

Abstract: BACKGROUND: Tissue engineering enables the production of three-dimensional microtissues which mimic naturally occurring conditions in special tissues. These 3D culture systems are particularly suitable for application in regenerative medicine or experimental pharmacology and toxicology. Therefore, it is important to analyse the cells in their 3D microenvironment with regard to viability and differentiation. Tetrazolium assays (WST-8 and MTS) are still the methods of choice for estimating the number of living, metabolically active cells, with WST-8 being cell-impermeable compared to MTS. In contrast to these methods, the ATP assay is an endpoint method based on the luciferase-induced reaction of ATP with luciferin …after cell lysis. OBJECTIVE: We compared three methodologically different proliferation/toxicity assays (MTS, WST-8, ATP) in monolayer (2D) and 3D culture systems to improve the technically challenging determination of the number of viable cells. METHODS: Chondrocytes were isolated from human articular cartilage. Three different test systems (MTS, WST-8, ATP) were applied to monolayer cells (2D, varying cell numbers) and spheroids (3D, different sizes) in 96-well plates. The intracellular ATP concentration was determined by luciferase-induced reaction of ATP with luciferin using a luminometer. Formazan formation was measured spectrophotometrically after different incubation periods. Evaluation was performed by phase contrast microscopy (toxicity), correlation of cell count and ATP concentration or absorption signal (Gompertz function) and propidium iodide (PI) staining to proof the cell lysis of all cells in spheroids. RESULTS: In 2D culture, all three assays showed a good correlation between the number of seeded cells and the ATP concentration or absorption data, whereas the MTS-assay showed the lowest specificity. In 3D culture, the spheroid sizes were directly related to the number of cells seeded. The absorption data of the WST-8 and MTS assay correlated only for certain spheroid size ranges, whereas the MTS-assay showed again the lowest specificity. Only the measured intracellular ATP content showed a linear correlation with all spheroid sizes ranging from 100–1000 μm. The WST-8 assay revealed the second-best sensitivity which allows the measurement of spheroids larger than 240 μm. Phase contrast observation of monolayer cells showed toxic effects of MTS after 6 h incubation and no signs of toxicity of WST-8. Staining with propidium iodide showed complete lysis of all cells in a spheroid in the ATP assay. CONCLUSION: Among tetrazolium-based assays, WST-8 is preferable to MTS because of its non-toxicity and better sensitivity. When determining the number of viable cells in the 2D system, caution is advised when using the ATP assay because of its two-phase slope of the correlation graph concerning cell number and intracellular ATP. In 3D systems of human chondrocytes, the ATP-assay is superior to the other two test systems, as the correlation graph between cell number and intracellular ATP is biphasic. Since differentiation processes or other metabolic events can influence the results of proliferation and toxicity assays (determination of viable cells), this should be taken into account when using these test systems. Show more

Keywords: ATP assay, MTS, WST-8, human chondrocytes, spheroid, 3D culture, 2D culture

DOI: 10.3233/CH-248101

Citation: Clinical Hemorheology and Microcirculation, vol. 88, no. s1, pp. S3-S19, 2024

Authors: Spiesecke, Paul | Thiemann, Janine | Conen, Patrick | Clevert, Dirk-André

Article Type: Research Article

Abstract: Ultrasound is the most used interdisciplinary imaging technique in clinical routine for assessment of renal pathologies. This includes the monitoring of cystic renal lesions, which can be classified as non-complicated or complicated and by means of occurrence as solitary or multifocal lesions. The Bosniak-classification (I–IV) classifies renal cysts in 5 different categories and is used for decisions of further clinical treatment. This classification was developed for computed tomography and has been adopted for magnetic resonance imaging as well as contrast-enhanced ultrasound. In the following review article, cystic kidney lesions and their differentiation using contrast-enhanced ultrasound are presented and an overview …of the therapy options is given. In interventional procedures, CEUS can make a valuable contribution in histological sampling, reduce radiation exposure and, under certain circumstances, the number of interventions for the patient. Show more

Keywords: Contrast-enhanced ultrasound, kidney lesion, tissue vascularization, real-time imaging, intervention

DOI: 10.3233/CH-248102

Citation: Clinical Hemorheology and Microcirculation, vol. 88, no. s1, pp. S21-S33, 2024

Authors: Christer, Tim | Hüner, A. | Robering, Jan Willem | Mrowietz, Christof | Hiebl, Bernhard

Article Type: Research Article

Abstract:  The pig (Sus scrofa ) is the most widely used large animal model in Europe, with cardiovascular research being one of the main areas of application. Adequate refinement of interventional studies in this field, meeting the requirements of Russell and Burch’s 3 R concept, can only be performed if blood-contacting medical devices are hemocompatible. Because most medical devices for cardiovascular interventional procedures are developed for humans, they are tested only for compatibility with human blood. The aim of this study was therefore to determine whether there are differences in behavior of human and porcine platelets from commercial hybrid …pigs when they come into contact with borosilicate glass, which was used as an exemplary thrombogenic material. For this purpose, changes in platelet count, platelet volume and platelet expression of the activation markers CD61, CD62P and CD63 were measured using a modified chandler loop-system simulating the fluidic effects of the bloodflow. Commercial hybrid pig and human platelets showed significant adhesions to borosilicate glass but the commercial hybrid pigs platelets showed a significantly higher tendency to adhere to borosilicate glass. In contrast to human platelets the platelets of commercial hybrid pigs showed significant activation after 4 to 8 minutes exposure to borosilicate glass and there were differences among the ratios of surface and activation markers in between the platelets of both species. Show more

Keywords: Pig, commercial hybrid pig, platelet activation, platelet count, platelet volume, FACS, CD42a, CD61, CD62P, CD63

DOI: 10.3233/CH-248103

Citation: Clinical Hemorheology and Microcirculation, vol. 88, no. s1, pp. S35-S44, 2024

Authors: Kaiser, Ulrich | Kaltenhauser, Simone | Kaiser, Florian | Vehling-Kaiser, Ursula | Herr, Wolfgang | Stroszczynski, Christian | Becker, Claus | Dropco, Ivor | Jung, Ernst Michael

Article Type: Research Article

Abstract: BACKGROUND AND OBJECTIVE: Ultrasound-guided interventions (such as biopsies) of unclear lesions are indicated if microcirculatory changes indicate possible malignant lesions. These place high demands on the ultrasound device used. In order to potentially reduce the often associated high technical effort, the wireless ultrasound device Vscan AirTM was examined as a possible ultrasound device for the intervention biopsy. METHODS: As part of an advanced training course on Computertomographie- and ultrasound-guided biopsy and ablation procedures, participants were asked about the image quality of the handheld device used by means of questionnaires. Various lesions were evaluated at a depth of …1.0 to 5.0 cm in an in vitro liver model. The image quality was evaluated independently before, during and after the intervention. The rating scale contained values from 0 (no assessment possible) to 5 (maximum high image quality). A high-end device was used as a reference. RESULTS: A total of 11 participants took part in the study (n  = 4 male [36.4%], n  = 7 female [63.6%]). A total of five tumor like lesions at different depths (1 cm, 2 cm, 3 cm, 4 cm, >4 cm) were assessed separately. In all cases, an adequate biopsy of the target lesion (1 cm in length, core filling 5 mm) was successful. From a depth of 3 cm, the image quality of the mobile device increasingly decreased, but the image quality of the high-end system was still not impaired. Compared to the high-end device, there was a highly significant difference in image quality from a depth of 3 cm (p  < 0.01). Assessment by inexperienced examiners using a handheld device was adequately possible. CONCLUSIONS: Mobile interventional ultrasound represents a potential alternative for the biopsy of unclear tumorous lesions with microcirculatory disorders with limited depth localization. Show more

Keywords: Ultrasound, mobile ultrasound, high end ultrasound, in vitro model, tumor diagnostics, ultrasound interventions

DOI: 10.3233/CH-248104

Citation: Clinical Hemorheology and Microcirculation, vol. 88, no. s1, pp. S45-S56, 2024

Authors: Kaiser, Ulrich | Kück, Fabian | Stroszczynski, Christian | Jung, Ernst Michael | Greiner, Barbara

Article Type: Research Article

Abstract: OBJECTIVE: To assess diagnostic capabilities of a modern handheld ultrasound device (HUD) for portal vein (PV) evaluation in pediatric patients and to verify if age, body mass index (BMI) and object depth correlate to imagequality. METHODS: 45 patients (3.9 months– 17.9 years; 10.3 years±5.4) were examined using a HUD and cart-based high-end ultrasound system (HEUS). The intra-and extrahepatic PV was scanned using B-Mode and Color-coded Doppler sonography (CCDS). A five-point Likert scale was applied to evaluate image quality. Results were interpreted by two readers in consensus. Scores were compared between the scanners and correlated to age, BMI and …skin-to-portal-vein-distance (SPVD). The influence on image quality and the difference between the two devices were analyzed using ordinal and Bayesian logistic regression models. RESULTS: ≥4 points (mild or no limitations) were achieved by the HUD in 60% for B-Mode and 56% for CCDS. There was a statistically significant negative correlation between the image quality achieved by the HUD and the SPVD for B-Mode and CCDS. The effect of BMI and SPVD on having≥4 points differed significantly between the HUD and HEUS for B-Mode and for CCDS. CONCLUSIONS: Sufficient to excellent image quality for portal vein assessment in pediatric patients was achieved by the HUD except for the most deep-lying structures. Compared to HEUS, diagnostic performance of the HUD is lower, based on a negative correlation with object depth. Show more

Keywords: Handheld ultrasound, Vscan Air, vascular, portal vein, pediatric

DOI: 10.3233/CH-248105

Citation: Clinical Hemorheology and Microcirculation, vol. 88, no. s1, pp. S57-S68, 2024

Authors: Hinestrosa, Camila A. | Fuchs, Jochen | Denecke, Timm | Storch, Christiane | Dreyer, Antje | Kuthning, Anja | Reinhardt, Martin | Rio Bartulos, Carolina | Wiggermann, Philipp | Busse, Harald | Moche, Michael

Article Type: Research Article

Abstract: OBJECTIVE: In uterine artery embolization (UAE) for the treatment of fibroids, nondegradable particles permanently occlude the uterine artery (UA). These particles remain in the vessels and can cause secondary undesirable effects, such as severe pain after embolization and fertility issues. In this prospective experimental study, we aimed to evaluate the angiographic recanalization, local and systemic reactions, and uterine damage occurring after performing UAE with newly developed degradable starch microspheres (DSMs) in sheep. MATERIALS AND METHODS: Under general anesthesia, eight nonpregnant sheep underwent bilateral UAE using DSMs to achieve stasis. Angiographic evaluation was performed on days 1, 3 and …7 after embolization to assess in vivo recanalization. In addition, the angiographic series were scored via a modified embolization score. A postmortem tissue examination was performed to determine whether DSMs and foreign body inflammatory reactions were present and to assess uterine necrosis. RESULTS: Complete bilateral embolization of the UA and cervicovaginal branches was achieved in all treated animals. Recanalization of the occluded arteries was evident in 25 of 27 arteries during the angiographic evaluation. In all sheep, there were multifocal areas of uterine necrosis, and some uterine vessels contained intraluminal material consistent with DSMs. The average weight of both uterine horns was significantly correlated with both the number of microspheres needed for complete embolization (r  = 0.69, ρ <0.01) and the average percentage of necrosis in both uterine horns (r  = 0.64, ρ <0.05). CONCLUSIONS: Our findings demonstrated the efficacy of vascular embolization with DSM by inducing ischemic changes in the uterus and subsequent recanalization of previously occluded arteries. Show more

Keywords: Uterine artery embolization, degradable starch microspheres, animal models, angiography, leiomyoma

DOI: 10.3233/CH-248106

Citation: Clinical Hemorheology and Microcirculation, vol. 88, no. s1, pp. S69-S84, 2024

Authors: Senk, Karin | Rio Bartulos, Carolina | Belkoura, Jihane Minh-Châu | Schmid, Stephan | Schlosser-Hupf, Sophie | Jung, Ernst Michael | Wiggermann, Philipp | Einspieler, Ingo

Article Type: Research Article

Abstract: BACKGROUND: Monitoring liver changes is crucial in the management of liver fibrosis. Current diagnostic methods include liver function tests such as the Liver Maximum Capacity (LiMAx) test and measurements of liver stiffness. While the LiMAx test quantifies liver function through 13 C-methacetin metabolism, ultrasound (US) elastography noninvasively assesses liver stiffness. The relationship between the findings of these methods in patients with liver fibrosis is not fullyunderstood. OBJECTIVE: This study evaluated the correlation between LiMAx measurements of liver function and US elastography-based liver stiffness measurements to better understand the interplay between functional and structural liver parameters in fibrotic liver …disease. Additionally, the relationship between body mass index (BMI) and these parameters isevaluated. METHODS: This retrospective study analysed data from 97 patients who underwent both LiMAx testing and real-time elastography, resulting in a total data set of 108 examinations. The correlations between the results of the LiMAx test and elastography and their relationships with body mass index (BMI) were analysed. RESULTS: There was a significant negative correlation (r  = –0.25, p  < 0.05) between LiMAx test values and liver stiffness measurements. BMI was significantly negatively correlated with LiMAx values (r  = –0.29, p  < 0.001) but not significantly correlated with liver stiffness values. CONCLUSIONS: This retrospective study confirms the results of previous studies showing a notable but weak association between liver function and liver stiffness. Our results highlight the potential value of both tests as complementary tools for the evaluation of liver health, reinforcing the necessity for a multimodal approach to liver assessment. Show more

Keywords: Liver Maximum Capacity (LiMAx) test, liver function, ultrasound elastography, fibrosis

DOI: 10.3233/CH-248107

Citation: Clinical Hemorheology and Microcirculation, vol. 88, no. s1, pp. S85-S93, 2024

Authors: Zeitler, Christina | Braune, Steffen | Waldeck, Peter | Jung, Conrad G.H. | Küpper, Jan-Heiner | Petrick, Ingolf | Jung, Friedrich

Article Type: Research Article

Abstract: The microalgae Arthrospira platensis (AP), commonly known as Spirulina, has gained widespread popularity as a food supplement in recent years. AP is particularly abundant in protein, B vitamins, iron, magnesium, potassium, and various antioxidants. In this study we aimed to evaluate the effect of nitrate limitation in the AP culture medium on AP growth and composition. In addition, the cytotoxicity of the respective aqueous AP extracts on three different mammalian cell-lines (HepG2, Caco2, L929) was tested. AP was cultivated over a 10-day period under nitrogen-rich (Nrich : 1.8 g/L) and nitrogen-deficient (Nlimited : 0.2–0.4 g/L) conditions in two separate experiments, …each with three biological replicates (three bioreactors). Throughout the cultivation, the kinetic progress of dry biomass, pH, pigment content, the levels of essential elements (sulphur, phosphate, and nitrate) and the composition of elements in the harvested biomass was determined. While the biomass slightly but significantly differed, the phycocyanin concentration differed considerably (around 10-fold higher in the Nrich medium, p  < 0.05). Aqueous extracts of the Nrich medium had significantly stronger effects on the cell membrane integrity and the metabolic activity of the cells than extracts of the Nlimited medium. Particularly was the finding that AP had a significantly stronger toxic effect on the two tumour cell types (HepG2, Caco2) than on the non-tumour cells (L929). This study underscores the significance of nitrate content in the cultivation media of AP. Show more

Keywords: Nitrogen deprivation, culture medium, Arthrospira platensis , biomass productivity, in-vitro cytotoxicity

DOI: 10.3233/CH-248108

Citation: Clinical Hemorheology and Microcirculation, vol. 88, no. s1, pp. S95-S111, 2024

Authors: Apfelbeck, Maria | Loupas, Thanasis | Chaloupka, Michael | Clevert, Dirk-André

Article Type: Research Article

Abstract: Ultrasound is the most used interdisciplinary non-ionizing imaging technique in clinical pathologies of the testis. The testis may be affected by a plethora of different disorders such as vasculopathies, trauma, infections and manifestations of primary and secondary malignant masses. Conventional ultrasound represents the basic imaging modality of choice to assess scrotal disorders. Contrast-enhanced ultrasound (CEUS) can provide further information to distinguish between benign and malignant testicular mass lesions. The recent introduction of Super Resolution CEUS Micro-Vascular Imaging (MVI SR) and Time of Arrival (TOA SR) parametric mapping compliments the information provided by conventional CEUS, since these two new post-processing techniques …improve the visualization of microvascular structures with slow blood flow and provide high-resolution images of the peak contrast enhancement and temporal perfusion patterns. This paper gives a comprehensive overview of differential diagnoses of the testicular disorder and their corresponding sono-morphologic correlates based on representative cases of the Interdisciplinary Ultrasound Center of the University Hospital Munich. Show more

Keywords: Super Resolution CEUS imaging, Micro Vascular Imaging, Time of Arrival, seminoma, teratoma, Leydig cell tumor, abscess, ultrasound

DOI: 10.3233/CH-248109

Citation: Clinical Hemorheology and Microcirculation, vol. 88, no. s1, pp. S113-S125, 2024