Clinical Hemorheology and Microcirculation - Volume 78, issue 1

Authors: Ashraf, Fahmida | Ambreen, Tehmina | Park, Cheol Woo | Kim, Dong-IK

Article Type: Research Article

Abstract: PURPOSE: Cross limb stent graft (SG) configuration technique for endovascular aneurysm repair (EVAR) is employed for splayed aortic bifurcations to avoid device kinking and smoothen cannulation. The present study investigates three types of stent graft (SG) configurations for endovascular aneurysm repair (EVAR) in abdominal aortic aneurysm. A computational fluid dynamic analysis was performed on the pulsatile non-Newtonian flow characteristics in three ideally modeled geometries of abdominal aortic (AA) SG configurations. METHODS: The three planar and crosslimb SG configurations were ideally modeled, namely, top-down nonballet-type, top-down ballet-type, and bottom-up nonballet-type configurations. In top-down SG configuration, most of the device …is deployed in the main body in the vicinity of renal artery and the limbs are extended to the iliac artery. While in the bottom-up configuration, some of the SG device is deployed in the main body, the limbs are deployed in aortic bifurcation, and the extra stent graft of the main body is extended to the proximal aorta until the below of the renal artery. The effects of non-Newtonian pulsatile flow on the wall stresses and flow patterns of the three models were investigated and compared. Moreover, the average wall shear stress (AWSS), oscillatory shear stress index (OSI), absolute helicity, pressure distribution, graft displacement and flow visualization plots were analyzed. RESULTS: The top-down ballet-type showed less branch blockage effect than the top-down nonballet-type models. Furthermore, the top-down ballet-type configuration showed an increased tendency to sustain high WSS and higher helicity characteristics than that of the bottom-up and top-down non-ballet type configurations. However, displacement forces of the top-down ballet-type configuration were 40% and 9.6% higher than those of the bottom-up and top-down nonballet-type configurations, respectively. CONCLUSIONS: Some complications such as graft tearing, thrombus formation, limb disconnection during long term follow up periods might be relevant to hemodynamic characteristics according to the configurations of EVAR. Hence, the reported data required to be validated with the clinical results. Show more

Keywords: Abdominal aortic aneurysm, EVAR, hemodynamics, non-newtonian flow

DOI: 10.3233/CH-200996

Citation: Clinical Hemorheology and Microcirculation, vol. 78, no. 1, pp. 1-27, 2021

Authors: Wiesinger, Isabel | Jung, Friedrich | Jung, Ernst Michael

Article Type: Research Article

Abstract: The external perfusion software (VueBox™ ) for contrast-enhanced ultrasound (CEUS), enables the quantitative analysis of micro-vascularization within non-cystic lesions in terms of characterization and detection. This review summarizes our work about parathyroid gland, thyroid gland, liver, prostate and other tissues as well as original studies in the use of parametric perfusion imaging. Useful perfusion parameters are introduced.

Keywords: CEUS, perfusion imaging, contrast-enhanced ultrasound

DOI: 10.3233/CH-201040

Citation: Clinical Hemorheology and Microcirculation, vol. 78, no. 1, pp. 29-40, 2021

Authors: Farber, Paulo Luiz

Article Type: Research Article

Abstract: Low plasma estrogens, vitamin D deficiency, obesity, diabetes, cardiovascular diseases, thromboembolism, and impaired microcirculation are linked to the severity of covid-19. Studies have suggested that these comorbidities also are related to erythrocyte factors linked to increased blood viscosity in microcirculation such as erythrocyte aggregation and erythrocyte deformability. Increased blood viscosity in microcirculation can lead to a decrease in oxygenation and nutrition of tissues. Therefore erythrocyte aggregation and erythrocyte deformability may be involved in covid-19 severity, leading to tissue hypoxia and a decrease of drug concentration in affected organs. If this relationship is demonstrated, erythrocytes factors can be used to monitor …treatments for improve microcirculatory fluidity that may decrease covid-19 severity. Lifestyle improvement and treatments such as vitamin D and estrogens supplementation are some possible approaches to improve microcirculation and covid-19 prevention and treatment. Show more

Keywords: Covid-19, hemorheology, microcirculation, estrogen, diabetes, vitamin D, obesity, cardiovascular diseases

DOI: 10.3233/CH-201082

Citation: Clinical Hemorheology and Microcirculation, vol. 78, no. 1, pp. 41-47, 2021

Authors: Lian, Kai-Mei | Lin, Teng

Article Type: Research Article

Abstract: BACKGROUND: Researchers have evaluated the virtual touch tissue imaging (VTI) value in the diagnosis of breast lesions, mostly based on gray-scale. PURPOSE: This study aimed to evaluate the value of color-map virtual touch tissue imaging (CMV) in the diagnosis of breast lesions. METHODS: We retrospectively analyzed the VTI images of 55 breast lesions in 49 female patients who underwent an examination of breast lesions in our hospital from January 2019 to December 2019. The pathological results were taken as the gold standard. The receiver operating characteristic (ROC) curve of CMV was analyzed, and its diagnostic performance …was evaluated. Weighted Kappa (k ) statistics were used to assess the inter-observer agreement for CMV. RESULTS: A total of 55 breast lesions were included, including 19 malignant lesions and 36 benign lesions. Multivariate analysis showed that patients with higher CMV scores (P  = 0.014, odds ratio [OR] = 13.667, 95% confidence interval = 1.702–109.773) were independent predictors of breast cancer. The sensitivity, specificity, and the area under curve (AUC) of CMV were 94.47%, 72.22%, and 0.912. The CMV’s inter-observer agreement was almost perfect among radiologists with different work experience (k  = 0.854, standard error = 0.049, 95% CI = 0.758–0.950). CONCLUSIOS: CMV has high accuracy and repeatability in the diagnosis of malignant breast lesions. Show more

Keywords: Breast lesion, ultrasound, elastography

DOI: 10.3233/CH-201088

Citation: Clinical Hemorheology and Microcirculation, vol. 78, no. 1, pp. 49-56, 2021

Authors: Kim, Kwan Wook | Kim, Sang Woo | Lim, Soyeon | Yoo, Kyung-Jong | Hwang, Ki-Chul | Lee, Seahyoung

Article Type: Research Article

Abstract: Hexokinase 2 (HK2) is a metabolic sensor that couples glycolysis and oxidative phosphorylation of mitochondria by binding to the outer mitochondrial membrane (OMM), and it also has been implicated in induction of apoptotic process by regulating the integrity of OMM. When HK2 detaches from the mitochondria, it triggers permeability increase of the OMM and subsequently facilitates the cytosolic release of cytochrome c, a major apoptosis-inducing factor. According to previous studies, a harsh microenvironment created by ischemic heart disease such as low tissue oxygen and nutrients, and increased reactive oxygen species (ROS) can cause cardiomyocyte apoptosis. Under these conditions, the expression …of HK2 in heart significantly decrease and such down-regulation of HK2 was correlated to the increased apoptosis of cardiomyocytes. Therefore, prevention of HK2 down-regulation may salvage cardiomyocytes from apoptosis. MicroRNAs are short, non-coding RNAs that either inhibit transcription of target mRNAs or degrade the targeted mRNAs via complementary binding to the 3’UTR (untranslated region) of the targeted mRNAs. Since miRNAs are known to be involved in virtually every biological processes, it is reasonable to assume that the expression of HK2 is also regulated by miRNAs. Currently, to my best knowledge, there is no previous study examined the miRNA-mediated regulation of HK2 in cardiomyocytes. Thus, in the present study, miRNA-mediated modulation of HK2 during ROS (H2 O2 )-induced cardiomyocyte apoptosis was investigated. First, the expression of HK2 in cardiomyocytes exposed to H2 O2 was evaluated. H2 O2 (500 μM) induced cardiomyocyte apoptosis and it also decreased the mitochondrial expression of HK2. Based on miRNA-target prediction databases and empirical data, miR-181a was identified as a HK2-targeting miRNA. To further examine the effect of negative regulation of the selected HK2-targeting miRNA on cardiomyocyte apoptosis, anti-miR-181a, which neutralizes endogenous miR-181a, was utilized. Delivery of anti-miR-181a significantly abrogated the H2 O2 -induced suppression of HK2 expression and subsequent disruption of mitochondrial membrane potential, improving the survival of cardiomyocytes exposed to H2 O2 . These findings suggest that miR-181a-mediated down-regulation of HK2 contributes to the apoptosis of cardiomyocytes exposed to ROS. Neutralizing miR-181a can be a viable and effective means to prevent cardiomyocyte from apoptosis in ischemic heart disease. Show more

Keywords: Hexokinase 2, miR-181a, reactive oxygen species, ischemic heart disease, cardiomyocytes, apoptosis

DOI: 10.3233/CH-200924

Citation: Clinical Hemorheology and Microcirculation, vol. 78, no. 1, pp. 57-68, 2021

Authors: Lei, Weijuan | Lin, Juanjuan | Liu, Fang | Chen, Nina

Article Type: Research Article

Abstract: PURPOSE: Acute myeloid leukemia (AML) is a type of hematologic malignancy. This study was attempt to explore the effect of long noncoding RNA GAS6 antisense RNA1 (GAS6-AS1) on pediatric AML and the regulation mechanisms. METHODS: GAS6-AS1, microRNA-370-3p (miR-370-3p), and Tetraspanin3 (TSPAN3) expression in bone marrow (BM) tissues and cells was determined by qRT-PCR. The correlation between GAS6-AS1 and clinicopathological features of pediatric patients with AML was assessed. In vitro , viability and migration and invasion of AML cells were evaluated via MTT and transwell assays, respectively. Interactions among GAS6-AS1, miR-370-3p, and TSPAN3 were revealed by dual-luciferase reporter assays. …Western blot was applied to confirm the protein expression of TSPAN3. RESULTS: GAS6-AS1 and TSPAN3 expression was elevated in BM tissues of pediatric patients with AML and AML cells, but miR-370-3p expression was reduced. GAS6-AS1 expression was positively related to French-American-British (FAB) classification in pediatric patients with AML. In vitro , GAS6-AS1 deficiency restrained the viability, migration, and invasion of AML cells. Additionally, GAS6-AS1 mediated miR-370-3p expression indeed and TSPAN3 was identified as a target of miR-370-3p. Furthermore, miR-370-3p overexpression repressed the protein expression of TSPAN3. The feedback experiments demonstrated that miR-370-3p inhibition or TSPAN3 overexpression mitigated the suppressive effect of sh-GAS6-AS1 on the tumorigenesis of AML cells. CONCLUSION: GAS6-AS1 silencing restrained AML cell viability, migration, and invasion by targeting miR-370-3p/TSPAN3 axis, affording a novel therapeutic target for pediatric AML. Show more

Keywords: GAS6-AS1, acute myeloid leukemia, viability, miR-370-3p, TSPAN3

DOI: 10.3233/CH-201039

Citation: Clinical Hemorheology and Microcirculation, vol. 78, no. 1, pp. 69-81, 2021

Authors: Schierling, Wilma | Bachleitner, Kathrin | Kasprzak, Piotr | Betz, Thomas | Stehr, Alexander | Pfister, Karin

Article Type: Research Article

Abstract: BACKGROUND: Acute lower limb ischemia (ALI) is associated with a high risk of limb loss and death. OBJECTIVE: The present study evaluates the safety of intraoperative, local urokinase lysis in patients with ALI and crural artery occlusion. METHODS: A total of 107 patients (115 legs) were treated surgically for ALI with additional intraoperative urokinase lysis to improve the outflow tract. Minor and major bleeding as well as efficacy of treatment and amputation-free survival were investigated. RESULTS: Complete restoration of at least one run-off vessel was achieved in 64%. Collateralization was improved in 34%. Lysis …failed in 2%. Major amputation rate was 27% overall (12% within 30 days) and depended on Rutherford class of ALI (overall/30 day: IIa 11%/6%; IIb 20%/17%; III 37%/15%). Amputation-free survival turned out to be 82% after 30 days, 58% after one, and 41% after five years. Minor bleeding occurred in 21% (24/115) and major bleeding in 3.5% (4/115). One of these patients died of haemorrhage. No patient experienced intracranial bleeding. CONCLUSION: Intraoperative urokinase lysis improves limb perfusion and causes low major and intracranial bleeding. It can be safely applied to patients with severe ischaemia when surgical restoration of the outflow tract fails. Show more

Keywords: Acute limb ischemia, bleeding, lysis, safety, thrombectomy, urokinase

DOI: 10.3233/CH-201049

Citation: Clinical Hemorheology and Microcirculation, vol. 78, no. 1, pp. 83-92, 2021

Authors: Troeltzsch, Daniel | Shnayien, Seyd | Gaudin, Robert | Bressem, Keno | Kreutzer, Kilian | Heiland, Max | Hamm, Bernd | Niehues, Stefan

Article Type: Research Article

Abstract: BACKGROUND: Post-therapeutic tissue is bradytrophic and thus has low perfusion values in PCT. In contrast, malignant tissue is expected to show higher perfusion values as cancer growth partially depends on angiogenesis. OBJECTIVES: This prospective study investigates perfusion computed tomography (PCT) for the post-therapeutic detection of cancer in the head and neck region. METHODS: 85 patients underwent PCT for 1) initial work-up of head and neck cancer (HNC; n =22) or 2) for follow-up (n =63). Regions of interest (ROIs) were placed in confirmed tumour, a corresponding location of benign tissue, and reference tissue. Perfusion was calculated …using a single input maximum slope algorithm. Statistical analysis was performed with the Mann-Whitney U-test. RESULTS: PCT allowed significant differentiation of malignant tissue from post-therapeutic tissue after treatment for HNC (p =0.018). Significance was even greater after normalization of perfusion values (p =0.007). PCT allowed highly significant differentiation of HNC from reference tissue (p <0.001). CONCLUSIONS: PCT provides significantly distinct perfusion values for malignant and benign as well as post-therapeutically altered tissue in the head and neck area, thus allowing differentiation of cancer from healthy tissue. Our results show that PCT in conjunction with a standard algorithm is a potentially powerful HNC diagnostic tool. Show more

Keywords: Diagnostic imaging, head and neck cancer, oral squamous cell carcinoma, perfusion computed tomography

DOI: 10.3233/CH-200919

Citation: Clinical Hemorheology and Microcirculation, vol. 78, no. 1, pp. 93-101, 2021

Authors: Werner, Jens Martin | Zidek, Martin | Kammerer, Sylvia | da Silva, Natascha Platz Batista | Jung, Friedrich | Schlitt, Hans Jürgen | Hornung, Matthias | Jung, Ernst-Michael

Article Type: Research Article

Abstract: OBJECTIVE: To assess the impact and procedural input of intraoperative ultrasound (IOUS) with contrast-enhanced ultrasound (CEUS) and ultrasound elastography on surgical decision making during the procedure and consequently the outcome after hepato-pancreatico-biliary (HPB) surgery. MATERIALS AND METHODS: Data of 50 consecutive patients, who underwent HPB surgery from 04/2018 to 07/2018 were prospectively collected for this study. During surgery, IOUS with a high-resolution ultrasound device using CEUS after bolus injection of 2.4–5 ml dulphur hexafluoride microbubbles using a 6–9 MHz probe and a share wave and strain elastography was performed by an experienced examiner. Process and time analysis were carried out …using mobile phone timer. RESULTS: The IOUS with CEUS and elastography correctly identified 42 malignant tumors and 4 benign lesions. In 3 cases, the examination provided false positive result (identifying 3 benign lesions as malignant) and in 1 case a malignant lesion was incorrectly assessed as benign (sensitivity 97,7%, specificity 57,1%, PPV 93,3% and NPV 80%). The specific question by the surgeon could be answered successfully in 98% of the cases. In 76% of the cases, there was a modification (42%) or a fundamental change (34%) of the planned surgical approach due to the information provided by the IOUS. Within the last group, the IOUS had a major impact on therapy outcome. In 7 patients an additional tumor resection was required, in 5 patients the tumor was assessed as inoperable, and in total in 5 patients an intraoperative RFA (4/5) or postoperative RITA (1/5) was required. Regarding procedural input, there was only a slight, but significant difference between the transport and set-up times before the intraoperative use (mean: 14 min 22 s) and the return transport (mean 13 min 6 s), (p  = 0,038). The average examination time was 14 minutes, which makes only one third of the overall time demand. CONCLUSION: Combination of IOUS with CEUS and elastography in oncological HPB surgery provides valuable information that affects surgical decision-making. The procedural input of about 45 minutes seems to be a good investment considering the improvement of the surgical procedure and a significant modification of the therapy approach in the majority of the cases. Show more

Keywords: Surgical decision-making, hepato-pancreatico-biliary surgery, CEUS, elastography

DOI: 10.3233/CH-201031

Citation: Clinical Hemorheology and Microcirculation, vol. 78, no. 1, pp. 103-116, 2021