Decrease In Wall Thickness Research Articles

Left ventricular remodeling following septal myectomy in hypertrophic obstructive cardiomyopathy

ObjectivesThe purpose of this study is to determine whether or not left ventricular remodeling can be induced after septal myectomy in patients with obstructive hypertrophic cardiomyopathy, and if so, how it occurs, using gated cardiac computed tomography. MethodsFifty patients with hypertrophic obstructive cardiomyopathy who underwent septal myectomy along the septal band between March 2016 and July 2020 were retrospectively reviewed. Recent consecutive 19 patients underwent postoperative cardiac computed tomography. In these patients, volumes of the septal band and thickness of 17 left ventricular myocardial segments were measured to determine the changes after surgery. ResultsThe resection volume predicted by preoperative computed tomography and the actual resection volume were 6.7 ± 3.3 mL and 6.4 ± 2.7 mL. In-hospital mortality was 0%. Moderate or greater mitral valve regurgitation and systolic anterior motion decreased from 56% to 6% and 86% to 6%, respectively. Median preoperative ventricular septal thickness and left ventricular outflow tract pressure gradient at rest decreased from 20.0 mm (interquartile range, 17.0-24.0 mm) and 74.0 mm Hg (interquartile range, 42.5-92.5 mm Hg) to 14.0 mm (interquartile range, 11.5-16.0 mm) and 15.5 mm Hg (interquartile range, 12.1-21.5 mm Hg), respectively. Postoperative computed tomography confirmed a reduction in septal band volume of 5.7 ± 2.8 mL. Total left ventricular myocardial volume was reduced by 12.9 ± 8.8 mL, which exceeded the volume reduction of the resected septal band. All segments except the basal inferior and basal inferolateral regions showed a significant decrease in wall thickness by a median of 6.4%. ConclusionsProperly performed septal myectomy may induce remodeling of the entire left ventricle, not just the resected area.

Dielectric-based tissue thickness measured during radiofrequency ablation catheter

Abstract Funding Acknowledgements Type of funding sources: None. A new dielectric-based method of KODEX-EPD mapping system (EPD Solutions) for measuring tissue thickness at the catheter-tissue interface has recently been developed. We reported preliminary data on real-time catheter-based measuring myocardial wall thickness in vivo, during typical atrial flutter (AFL) RF ablation. The Kodex version used to perform this type of analysis is a version not commercially available yet but only for case replay and research purpose, not used in clinical practice. The study population consisted of 12 consecutive patients, suffering from symptomatic paroxysmal or persistent cavo-tricuspid isthmus (CTI) dependent. The Wall Viewer (WV) function is measured by assessing a series of dielectric signals derived directly from real-time local interrogation of the catheter-tissue interface. WV is displayed in millimeters, with either high or low confidence levels per met or unmet prerequisite acquisition criteria respectively and it is displayed as a color code scale (Fig. 1, A). The anatomy of the CTI was identified using the 4mm MAP-iT irrigated ablation catheter. A suitable starting point for the ablation, in the proximity of the tricuspid valve, and a final location in the junction between the inferior vena cava and the right atrium, were precisely defined based on electrograms recorded. Subsequently, "point by point" CTI ablation was performed delivering RF energy with 30/40 Watts for 20-40 seconds with an interlesion distance ≤6 mm. 9 patients had paroxysmal common AFL, 3 persistent common AFL. The mean age was 64±9 years, 10 (83%) were male. The mean body mass index was 30±6, 9 (75%) patients had hypertension, and 1 (8%) had coronary artery disease. The mean procedure time was 37±13 min, the mean fluoroscopic time was 690±378 s, the mean RF time 763±205 s, with a mean number of RF pulses of 28±7. The mean cavo-tricuspid isthmus length was 29.5±2.6 mm. The atrial wall thickness was significantly higher close to the tricuspid annulus than close to the inferior vena cava (3.6±0.5 mm vs 2.4±0.3 mm, p<0.001) and a trend towards a progressive decrease of atrial wall thickness was observed moving the mapping catheter from the tricuspid valve to the inferior vena cava (Fig. 1, B). Acute bidirectional cavo-tricuspid isthmus block was achieved in all patients without any complications. We first describe a new mapping technology that allows atrial wall thickness measurement and, as expected, the wall thickness was higher close the tricuspid annulus and lower towards the inferior vena cava. The possibility to calculate the substrate thickness before RF delivery could deeply change the way to perform RF ablation, allowing a tailored energy delivery thus increasing the efficiency of the procedures and potentially reduction of the risk of complications.

Pathobiochemical aspects of alcoholic cardiomyopathy. The role of hydrogen sulfide in the mechanism of cardiocytoprotection (a review)

Aim: systematization of knowledge about the pathobiochemical mechanisms of heart disease in alcoholic cardiomyopathy (ACMP) and the search for promising ways of cardiocytoprotection. Alcohol abuse is an important medical and social problem, risk factor for metabolic disorders, malnutrition, cancers, dementia, neuropathy, and others. Consumption of large amounts of ethanol increases a risk of sudden cardiac death and cardiac arrhythmias. The term “alcoholic cardiomyopathy” describes a heart disease in people with a history of long-term alcohol use. ACMP is characterized by left ventricular dilatation, decreased wall thickness and (at the later stages) decreased left ventricular ejection fraction (less than 40 %). Analysis of literature data about the mechanisms of alcohol-induced cardiotoxicity revealed trigger factors for myocardial damage. Negative effect of ethanol on the heart is realized through induction of oxidative-nitrosative stress, apoptosis, inflammation, fibrogenesis, hypoenergetic state and ion pump dysfunction, development of endothelial dysfunction, impaired ribosomal synthesis. In-depth study of biochemical mechanisms and identification of new molecular targets, integrated into the pathogenesis of ACMP, will optimize the pharmacotherapy for this pathology. Hydrogen sulfide (H2S), is a metabolic factor involved in the regulation of cardiovascular activity. Use of exogenous H2S has potent cardioprotective properties in cardio-vascular diseases. Donors of H2S and H2S-releasing drugs (hybrid molecules – H2S-aspirin, H2S-NO) show a powerful cardioprotective role in various pathological conditions. Therefore, it is advisable to further study the role of H2S system in the pathogenesis of ACMP to develop new approaches to more effective treatment of this disease. Conclusions. Modulation of the H2S level in the organism may be a predictor of the severity of myocardial damage, as well as a promising vector in pharmacotherapy, including alcoholic cardiomyopathy.

Early sonographic response to a new medical therapy is associated with future treatment response or failure in patients with inflammatory bowel disease.

Gastrointestinal ultrasound (GIUS) accurately assesses inflammation and is responsive to changes in inflammatory bowel disease. This study aimed to determine the prognostic utility of sonographic response in the first 14 weeks of a newly-instituted therapy with therapeutic response at 46 weeks and to compare its performance with standard clinical assessment tools. Patients with sonographic evidence of inflammation were assessed by GIUS, clinical activity, serum C-reactive protein and faecal calprotectin again 2, 6 and 14 weeks after commencing a new biologic or thiopurine. Treatment failure was defined as undergoing surgery, hospitalisation, escalation of dosage or introduction of new medication over 46-weeks' follow-up. Sonographic response was defined as a decrease in bowel wall thickness and improved vascularity. In 31 patients (median age 49 years, 74% Crohn's disease), sonographic response at 14 weeks [OR 19.3, 95% confidence interval (CI), 3.23-101.10; P = 0.0054] and faecal calprotectin (P = 0.018), but no clinical disease activity or C-reactive protein, were predictive of subsequent treatment response. Sonographic response alone was predictive at week 6 (P = 0.016), but not week 2. 16% reduction in bowel wall thickness at 6 weeks (area-under-the-receiver-operator-curve=0.86; P = 0.002; sensitivity 72%, specificity 90%), with similar performance for 10% at 14 weeks, was associated with treatment response. Sonographic response as early as 6 weeks after initiation of a new therapy may accurately predict treatment outcomes over 46 weeks and is superior to other markers used to monitor disease activity.

Physical Properties and Boundary Influence of Singularity in Fluid Pipelines Based on Vibration Wave’s Transmission Characteristics

The pipeline, as the fifth largest transportation tool after railway, highway, waterway, and air transportation, has been widely used in industrial production and life. However, in the process of pipeline operations, rapid opening and closing of valves or pump stopping can lead to water hammer. The periodic pressure wave caused by water hammer can be much greater than the normal operating pressure of the pipeline. Because of water hammer, pipelines are susceptible to aging and damage that may cause local wall thickness reduction or local pipe property change. In this paper, singularity is defined as an abnormal state area during the use of the pipeline. It includes the corrosion thinning area of the pipeline wall, changes in the supporting environment around the pipeline, and the uneven stress area applied to the pipe wall because of water hammer vibrations. Different types of singular points have different characteristics. We focus on two types of singular points’ characteristics in this paper: (1) nonpenetrating damage on the outer surface of pipe; and (2) local material change. Specifically, if the pipe wall thickness decreases locally due to pipeline damage, the ratio of wall thickness reduction to wall thickness corresponds to the depth of singularity, and the decrease of local wall thickness corresponds to the increase of the depth of singularity. The axial expansion of damage corresponds to the increase of the axial length of singularity. Similarly, when the local material of the pipe changes, the singularity corresponds to the part of the pipe where the local material changes. This part of the singularity material can be other material types that are inconsistent with the pipe material, such as the connecting part of a PVC pipe in two sections of steel pipe. Note that most detection methods of the pipeline leakage are post-leakage detection, which brings risks such as the wasting of resources. In this paper, the harmful energy of water hammer is taken as the excitation source of the pipeline, and the vibration characteristics of the pipeline are studied. The singularity characteristics of the pipeline relate to the vibration of the pipeline excited by water hammer, which provides a basis for the detection before the singularity becomes the leakage point. Based on COMSOL software, the fluid-free pipeline model and the water hammer excited flow pipeline model are constructed. Detection points are set to detect different characteristics (depth characteristics, axial length characteristics, and material characteristics) of pipeline singularity, and the influence of the singularity on the pipeline stress, pressure, displacement, and other parameters is studied. When the depth of singularity is 20%, 40%, 60%, and 80% of the wall thickness, the pipeline’s maximum pressure increases with the increase of the depth of singularity; when the water hammer is applied to the pipeline, the depth of singularity increases, the pipeline’s maximum stress increases, and the displacement at the singular point of the pipeline decreases. Compared with the depth of the singularity, the axial length of the singularity is 0.02, 0.025, 0.03, 0.035, and 0.04 m, respectively. It has a lesser influence on the pipeline characteristics than the depth of singularity. The material change of the singularity will also have an impact on the pipeline vibration, a factor which can be applied to the seismic design of pipelines. Detection before the singularity becomes a leak is the objective. These phenomena show that, based on vibration wave transmission characteristics, it is feasible in mechanism to achieve this objective.

Aspergilloma Morphology on Computed Tomography Angiography and its Clinical Impact in Patients of Haemoptysis

Amongst various manifestations of pulmonary aspergillosis, chronic pulmonary aspergillosis (CPA) is the most common. We conducted this study to identify different morphological forms of CPA, on computed tomography angiography (CTA), and to correlate these with clinical presentation, as well as, associated imaging features. The study design was cross-sectional, with a final sample size of 65 patients, recruited over a period of 2years from January 2017 to October 2018. Patients with past history of tuberculosis (TB), presenting with haemoptysis and found to have aspergilloma on computed tomography and lab tests were included in the study. All patients underwent CTA for evaluation of haemoptysis. Three morphological types of intracavitary aspergilloma on imaging were identified: type 1-nodular soft tissue along the cavity-wall, type-2 soft tissue density with multiple air lucencies and type-3 homogenous soft tissue opacity with air-crescent sign. Aspergilloma types were correlated with grade and duration of haemoptysis, associated imaging findings and vascularity score on CTA. Mean age of the patients was 40.97 +/- 13.69 years. As the type of aspergilloma changed from 1 to 3, there was a decrease in cavity wall thickness, peri-cavitary inflammation and vascularity. It is the type 1 and 2 aspergillomas, which caused more inflammation in the lungs, and hence recruited more abnormal vasculature. No significant correlation was found between haemoptysis severity and type of aspergilloma; type 3 aspergilloma however had longer duration of haemoptysis.In conclusion, the initial stages of formation of aspergilloma (type 1 and 2) cause more parenchymal inflammation and symptoms. The classical Monod sign is observed in the late stage of aspergilloma, since the peri-cavitary inflammation is reduced by then and thus the symptoms.

Anisotropic Growth of the Primary Dendrite Arms in a Single‐Crystal Thin‐Walled Nickel‐Based Superalloy

The influence of the withdrawal rate and wall thickness on the primary and secondary dendrite arm spacings of single‐crystal specimens manufactured by the Bridgman process is investigated. Thin‐walled specimens with wall thicknesses of 0.4, 0.8, 1, and 2 mm are compared with conventional cast single‐crystal cylindrical specimens with a diameter of 15 mm of the nickel‐based superalloy MAR M247LC. It is found that the average primary dendrite arm spacing decreases slightly with decreasing wall thickness, whereas the secondary dendrite arm spacing is relatively independent of the cast wall thickness. The slight decrease in primary dendrite arm spacing relates to an ≈ 0.2 mm wide boundary zone next to the ceramic mold/cast metal interface that is not only present in the thin‐walled specimens, but also within cylindrical single‐crystal specimens. Within this boundary zone, the primary dendrite arm spacing is anisotropic. While the spacing of two dendritic cores sitting aside each other (y‐direction) remains at the bulk value, the spacing of two dendritic cores sitting in line with the interface normal (x‐direction) is significantly reduced.

CT Appearances in Treated Abdominal Tuberculosis: A Radiologist's Dilemma

Abstract Objective To study the CT appearances of the abdomen after completion of antitubercular therapy (ATT) in adult patients. Methods Multidetector CT scan abdomen was done in 20 adults within 1 month of completing ATT. CT appearances were compared with pretreatment scans which were available in 7 cases. Results We found that residual ileocecal wall thickening and enhancement was significant (p < 0.05) after treatment in cases of ileocecal tuberculosis (TB). Mild decrease in wall thickness and diameter of the involved dilated small bowel loops was seen. Numerous large, matted nodes with necrosis persisted in the mesentery and retroperitoneum in treated TB, but reduction in the size of nodes was appreciated. Conclusion Our results help to fill the vacuum in the database of CT appearances in treated abdominal TB. Persistence of bowel changes and lymph nodes should not be mistaken for recurrence of TB or residual disease.

The Effects of Calina Papaya Leaf Ethanol Extract On Estrus Cycle And Uterus Morphology of Wistar Rats

Calina papaya leaf is an Indonesian papaya plant type that has the potential to be used as a medicinal plant. Phytochemical compounds found in papaya leaves act as antifertility agents. The research aimed to study the antifertility effect of Calina papaya leaf ethanol extract on estrus cycle and uterine morphology of wistar rats. The experiment lasted 30 days and involved 25 female wistar rats. The treatment consisted of 5 groups, namely K (distilled water), K+ (contraceptive pill), P1 (Calina papaya leaf ethanol extract 200mg/KgBW), P2 (Calina papaya leaf ethanol extract 300mg/KgBW), and P3 (Calina papaya leaf ethanol extract 400mg/KgBW). The parameters of estrus cycle consisted of estrus cycle phase, total cycle and estrus cycle ratio. Uterus morphological parameters consist of wall thickness of the endometrium, myometrium, and perimetrium. The estrus cycle examination was carried out every day using the vaginal smear method (Giemsa 5%). On the 31st day, surgery was performed and the uterus was taken for histological observation using the paraffin method (HE staining). Data were analyzed using One Way ANOVA with further Duncan’s test. The results showed that a dose of 400 mg/KgBW could affect the estrus cycle with accelerate the estrus phase and increase the estrus cycle ratio compared to the control (P0.05). There was a decrease in endometrium and myometrium wall thickness at a dose of 400 mg/KgBW compared to the control (P0.05). The conclusion of the study is that the ethanol extract of Calina papaya leaves at a dose of 400 mg/KgBW has the potential to be a natural antifertility agent on female wistar rats.

Abstract 9806: Cardiac Remodeling Post Transcatheter Aortic Valve Replacement: A Comparison Between Veteran and Non-Veteran Populations

Background: Transcatheter aortic valve replacement (TAVR) is increasingly utilized in the treatment of aortic valve disease. We assess echocardiographic changes over time to evaluate cardiac remodeling following TAVR between Veteran (VA) and non-VA populations. Methods: Retrospective analysis of 121, single operator TAVR procedures completed between March 2018 and June 2020 at the University of Illinois Hospital in Chicago, IL. Patients included those referred from the affiliated Jessie Brown Veteran Affairs hospital with the following inclusion criteria: transthoracic echocardiogram (TTE) at baseline and 6-month follow-up. Chi-Square tests were used to analyze categorical variables, paired t-tests for continuous variables, and multivariate analysis for subgroups. Results: One hundred and fifteen patients (VA: 59, non-VA: 56) were included in this study. The population had a mean age of 77.0 vs 73.2, BMI of 28.2 vs 30.4, 96.6% vs 56.6% male (p<0.001), and 57.6% vs 33.9% White (p=0.011) between VA and non-VA patients respectively. Overall, there was no significant difference in chamber dimensions, LVEF, and RVSP; however, there was a significant decrease in wall thickness. Multivariate subgroup analysis showed no significant difference between groups except for RVSP. Conclusion: Overall, our study shows positive cardiac remodeling post TAVR, but there is no significant difference when comparing VA to non-VA populations. Although additional studies with larger sample sizes are warranted, the lack of disparity between these subgroups is reassuring.

Identifying structure-property relationships of micro-architectured porous scaffolds through 3D printing and finite element analysis

This study integrates 3D printing and finite element analysis (FEA) to investigate the effect of micro-architectural characteristics on the mechanical properties of porous scaffolds. The studied characteristics include the thickness of the scaffold walls and the number of domains at the cross-section. We use 3D printing to fabricate scaffolds of deliberately designed microstructures to enable strict architecture control of the scaffolds. The longitudinal compressive properties of different scaffolds are first analyzed through experimental testing. Then, FEA is conducted to investigate the mechanical properties and the deformation mechanisms of the scaffolds. We find that decreasing wall thickness leads to failure mechanism transition from wall compression failure to buckling instability. For scaffolds with different wall thicknesses, the failure mechanisms and the critical loads are evaluated using the theory of thin plate buckling. For the characteristic of the number of domains, both experimental and FEA results show increasing effective stiffness with increasing domains. Interestingly, we find that with the material properties extracted from a single wall scaffold, the computational models tend to overestimate the effective compression modulus of scaffolds with larger numbers of walls or domains than the experimental data. This observation indicates possible size-dependent material properties in 3D printed structs. Our study demonstrates that integrating experiments and computational modeling can provide fundamental insights into the mechanical properties and deformation mechanisms of micro-architectured scaffolds and unveil unique small-scale material behaviors.

Tailoring amlodipine release from 3D printed tablets: Influence of infill patterns and wall thickness

The aim of this study was to investigate the impact of infill patterns on the drug release of 3D-printed tablets and the possibility of tailoring drug release through the use of excipients. Furthermore, the influence of wall thickness was evaluated. Amlodipine was used as a model drug, polyvinyl alcohol (PVA) as a polymer and excipients including sodium starch glycolate (SSG) and hydroxypropyl methyl cellulose (HPMC) HME 4 M were used. Four different formulations were prepared. Firstly, the substances were mixed and then extruded by hot melt extrusion to form filaments. The obtained filaments were used to print amlodipine tablets by fused deposition modeling (FDM) 3D-printing technique. Each formulation was printed in four different infill patterns: zigzag, cubic, tri-hexagon and concentric, while infill density remained constant (20%). The mechanical properties of the obtained filaments were also evaluated using three-point bend test. Amlodipine tablets were printed with varying wall thickness (1 mm, 2 mm and 3 mm) and varying infill patterns. With regard to the infill patterns, higher drug release was achieved with zigzag infill pattern. The simultaneous effect of excipients and infill patterns on amlodipine release has been described and modeled through self - organizing maps (SOMs), which visualize the effect of these variables. Self-organizing maps confirmed the fastest drug release when the zigzag pattern and SSG were used, but also showed that the presence of HPMC HME 4 M was not decisive for drug release rate. As for the wall thickness, higher drug release was achieved with decreasing wall thickness. The results indicated that proper selection of excipients and/or adjusting the infill pattern and wall thickness are ways of tailoring drug release in FDM 3D printing. This study draws the attention to the importance of adjusting the settings of the printer and the usage of excipients to produce release-tailored medications.

Determination of technological parameters of rock freezing systems based on the condition of maintaining design thickness of ice wall

Artificial freezing ensures the formation of a temporary ice wall around the shaft under construction, which prevents groundwater penetration into the shaft and increases the strength of rocks around the unsupported walls of the shaft until the permanent support is erected. The purpose of the study is to carry out thermotechnical calculation of ice wall with subsequent theoretical analysis of changing ice wall thickness with shifting to the passive freezing stage. The idea of the study is to determine these technological parameters based on the condition of maintaining the design ice wall thickness at the stage of passive freezing. The methodology and results of thermotechnical calculation of ice wall for the clay layer as applied to the case of the shafts under construction of a potash mine in the Republic of Belarus are presented. The thermal calculation of the ice wall was carried out numerically in the ANSYS software package using the finite element method. The findings of the numerical multiparameter modeling allowed theoretical analysis of ice wall thickness decrease with shifting to the passive freezing stage with higher brine temperature. The decrease in ice wall thickness was studied both during normal operation of the freezing station and at emergency operation mode caused by the failure of one of the freezing columns. Special attention in the analysis was paid to studying the influence of the duration of the active freezing stage and the distance between the columns on the decrease in the ice wall thickness. When analyzing changes in ice wall thickness at different distances between the freezing columns, it was found that the most common column spacing in the range from 1.1 to 1.3 m requires observing restrictions on the duration of active freezing to prevent a critical decrease in ice wall thickness during the passive freezing stage or decreasing the distance between the freezing columns. In this case, preservation of positive dynamics of ice wall thickness growth is ensured. For the clay layer considered in the study and the distance between the columns from 1.1 to 1.3 m, the minimum time of active freezing is also about 4.3 months. As a result of the analysis, the technological parameters of the freezing system (duration of the active freezing stage and the distance between the freezing columns) were determined, at which the ice wall thickness at the passive freezing stage did not become lower than the minimum permissible values calculated based on the strength and creep conditions.

3D geometry of femoral reaming for bone graft harvesting

The reamer-irrigator-aspirator (RIA) technique allows to collect large bone graft amounts without the drawbacks of iliac crest harvesting. Nevertheless, clinical cases with occurrence of femur fractures have been reported. Therefore, this study aimed to systematically investigate the three-dimensional geometry of the reamed bone as a function of the reaming diameter and its influence on the associated potential fracture pattern. Forty-five intact fresh-frozen human cadaveric femora underwent computed tomography (CT). They were randomized to three groups (n = 15) for reaming at a diameter of either 1.5 mm (Group 1), 2.5 mm (Group 2) or 4.0 mm (Group 3) larger than their isthmus using RIA. Reaming was followed by a second CT scan, biomechanical testing until failure and a third CT scan. All CT scans of each femur were aligned via rigid registration, and fracture lines were visualized. Subsequently, a decrease in wall thickness, cross-sectional area, and harvested bone volume have been evaluated. The total volume of the bone graft was significantly higher for Group 3 (7.8 ± 2.9 ml) compared to Group 1 (2.9 ± 1.1 ml) and Group 2 (3.0 ± 1.1 ml). The maximal relative decrease of the wall thickness was located medially (72.7%) in the third (61.4%), fourth (18.2%) and second (9.1%) eighth for all groups. As the diameter of the reaming increased, an overlap of the fracture line with the maximal relative decrease in wall thickness and a maximal average relative decrease of the cross-sectional area became more frequent. This suggests that a reaming-associated fracture is most likely to occur in this region.

Vascular Adaptation In Athletes Of Different Events

The existence of “athlete’s heart” is generally accepted, but the question of whether athletes exhibit vascular adaptation has not been fully addressed. PURPOSE: Investigated the indexes of arteries to determine whether arterial adaptations induced by exercise exist. METHODS: Examined the arteries of the dominant (D) and nondominant (ND) limbs of athletes and inactive subjects by duplex ultrasound. RESULTS: 1. In tennis athletes, IMT-to-lumen of arteries were lower than controls (carotid D: 0.013 ± 0.003 vs. 0.015 ± 0.003, ND: 0.013 ± 0.002 vs. 0.015 ± 0.003; brachial D: 0.026 ± 0.002 vs. 0.039 ± 0.011, ND: 0.038 ± 0.009 vs. 0.042 ± 0.013; p < 0.05). We found larger cross-sectional area of brachial artery (D: 20.96 ± 1.79 mm2) relative to the ND side (16.72 ± 0.93 mm2, p < 0.05) and both sides of controls (D: 13.37 ± 0.92 mm2, ND: 13.37 ± 0.85 mm2; p < 0.05). 2. Football athletes demonstrated lower IMT-to-lumen compared with controls (carotid D: 0.013 ± 0.002 vs. 0.015 ± 0.003, ND: 014 ± 0.003 vs. 0.015 ± 0.003; brachial D: 0.031 ± 0.009 vs. 0.039 ± 0.011, ND: 0.034 ± 0.010 vs. 0.042 ± 0.013; radial D: 0.075 ± 0.014 vs. 0.089 ± 0.018, ND: 0.087 ± 0.027 vs. 0.106 ± 0.021; femoral D: 0.013 ± 0.003 vs. 0.016 ± 0.006, ND: 0.013 ± 0.004 vs. 0.017 ± 0.005; p < 0.05). We found larger cross-sectional area of femoral artery (D: 42.59 ± 1.88 mm2) relative to the ND side (36.70 ± 1.75 mm2, p < 0.05) and D side of controls (34.87 ± 1.50 mm2, p < 0.05). 3. Swimmers demonstrated lower IMT-to-lumen compared with controls (carotid D: 0.013 ± 0.003 vs. 0.015 ± 0.003, ND: 0.014 ± 0.002 vs. 0.015 ± 0.003; brachial D: 0.028 ± 0.004 vs. 0.039 ± 0.011, ND: 0.033 ± 0.006 vs. 0.042 ± 0.013; radial D: 0.071 ± 0.021 vs. 0.089 ± 0.018, ND: 0.085 ± 0.019 vs. 0.106 ± 0.021; femoral D: 0.013 ± 0.002 vs. 0.016 ± 0.006, ND: 0.014 ± 0.003 vs. 0.017 ± 0.005; p < 0.05). The cross-sectional area of brachial (D: 17.36 ± 0.90; ND: 16.83 ± 0.67 mm2) and femoral arteries (D: 41.33 ± 1.63; ND: 39.05 ± 1.28 mm2) were larger than controls (brachial D: 13.96 ± 0.95 mm2, ND: 13.37 ± 0.85; femoral D: 34.87 ± 1.50 mm2, ND: 34.55 ± 1.62 mm2; p < 0.05). CONCLUSION: The results suggest that “athlete’s artery” has a systemic decreased wall thickness and a localized increased lumen area. These structural changes of artery are adaptations to exercise. Supported by the National Natural Science Foundation of China 32071174.

Effect of surgical treatment on myocardial strain in patients with pheochromocytoma and paraganglioma: a mini-review and meta-analysis.

Information on systolic dysfunction, as assessed by left-ventricular (LV) mechanics, in patients with pheochromocytoma after surgical treatment is scanty. We performed a systematic meta-analysis of speckle tracking echocardiographic studies to provide an updated comprehensive information on this issue. The PubMed, OVID-MEDLINE, and Cochrane library databases were analyzed to search for articles published from the inception up to May 31st 2021. Studies were identified using MeSH terms and crossing the following search items: "myocardial strain" "left ventricular mechanics", "speckle tracking echocardiography", "systolic dysfunction", "pheochromocytoma", and "paraganglioma". A total of 92 surgically treated patients with pheochromocytoma/paraganglioma were included in 3 longitudinal studies. Successful surgical treatment was associated with a decrease in relative wall thickness (SMD -0.25 ± 0.10, CI -0.45/-0.05, p < 0.01) and an improvement in global longitudinal strain (SMD -0.45 ± 0.10, CI -0.66/-0.24, p < 0.0001). The favorable effects of treatment on LV geometry and mechanics were not accompanied by significant changes in ejection fraction (SMD -0.07 ± 0.10, CI -0.27/0.12, p = 0.44). This meta-analysis adds a new piece of evidence, suggesting that surgical treatment of patients with pheochromocytoma impacts favorably on LV geometry and LV mechanics, and, more importantly, the assessment of LV changes in this setting can no longer rely on conventional echocardiographic parameters such as ejection fraction.

P283 Decrease in bowel wall thickness at intestinal ultrasound accurately detects early endoscopic remission and improvement in ulcerative colitis patients on tofacitinib: a longitudinal prospective cohort study

Abstract Background To assess disease activity in ulcerative colitis (UC) intestinal ultrasound (IUS) highly correlates with endoscopic outcomes. However, data on treatment response evaluated with IUS is limited. In this study we aim to evaluate bowel wall thickness (BWT) at follow-up to determine treatment effectiveness in moderate-severe UC patients treated with tofacitinib according to central read endoscopy and histology. Methods Patients with moderate-severe UC (endoscopic Mayo score (EMS)≥2) starting tofacitinib 10 mg bid were included. Disease activity was evaluated by recorded IUS cine-loops and video-taped endoscopies with biopsies from the sigmoid (SC) and descending colon (DC) at baseline and at 8 weeks. BWT and EMS were assessed per segment (SC and DC). Histology was scored for the SC with the Robarts Histology Index (RHI). BWT, EMS and RHI were centrally read and for IUS there was a second reader. Endoscopic remission (ERem) was defined as EMS=0, endoscopic improvement (EI) as EMS≤1 and endoscopic response (ERes) as a decrease of EMS≥1. For statistical analysis a Wilcoxon signed-rank and Spearman’s test were used. Area under the ROC was used to determine optimal cut-off values. Inter-observer agreement was analyzed by intra-class correlation coefficient (ICC). Results 29 patients were included and started tofacitinib. 10% reached complete ERem after 8 weeks, respectively. Per-segment analysis for EMS showed 22% and 53% reaching ER and 40% and 60% having EI in the SC and DC, respectively. BWT in SC and DC correlated highly with the EMS (rho=0.68, rho=0.75, both p&amp;lt;0.0001) and moderately with RHI (rho=0.49, p=0.002). Patients with EMS≥2 after 8 weeks had an increased BWT (SC: 4.32 ± 1.57 mm, DC: 4.38 ± 1.58 mm) when compared to ERem (SC: 2.10 ± 0.67 mm, DC: mean: 2.00 ± 1.18 mm, both p&amp;lt;0.0001) and EI (SC: 2.29 ± 0.76 mm, DC: 2.56 ± 1.38 mm, both p&amp;lt;0.0001) in the similar segment (Figure 1 and 2). BWT decreased after 8 weeks when there was ERes (SC: mean: -2.59 ± 1.44 mm, DC: -1.82 ± 1.01 mm, both p=0.007) and did not when there was no ERes (Figure 3). BWT cut-off values for ERem are reported in Figure 4. Furthermore, agreement for BWT in the SC and DC was excellent (ICC: 0.92 and ICC: 0.89), respectively. Conclusion BWT reduction showed early endoscopic remission, improvement and response after 8 weeks of tofacitinib treatment and correlated with histology in this central read cohort. Furthermore, accurate and reliable cut-off values for BWT in SC and DC were found for endoscopic remission and improvement. Therefore, IUS should be incorporated in the standard follow-up and close monitoring of UC patients.

Morphology and properties of hollow glass microspheres. Part 3. On the wall thickness of industrial hollow glass microspheres

Microscopic analysis of fragments of destroyed hollow glass microspheres was used to determine the thickness of their walls. It is revealed that the wall thickness of industrial microspheres can vary significantly even within a single glass microsphere. It is shown that as the diameter of hollow glass microspheres increases, the relative wall thickness decreases, and the degree of their heterogeneity increases. The wall thickness variability leads to a significant decrease in the level of critical pressure, which causes the destruction of microspheres, compared to the calculated one.

Transamniotic Stem Cell Therapy for Experimental Congenital Diaphragmatic Hernia: Structural, Transcriptional, and Cell Kinetics Analyses in the Nitrofen Model

Purpose: We examined select pulmonary effects and donor cell kinetics after transamniotic stem cell therapy (TRASCET) in a model of congenital diaphragmatic hernia (CDH). Methods: Pregnant dams (n = 58) received nitrofen on gestational day 9.5 (E9) to induce fetal CDH. Fetuses (n = 681) were divided into 4 groups: untreated (n = 99) and 3 groups receiving volume-matched intra-amniotic injections on E17 of either saline (n = 142), luciferase-labeled amniotic fluid-derived mesenchymal stem cells (afMSCs; n = 299), or acellular recombinant luciferase (n = 141). Pulmonary morphometry, quantitative gene expression of pulmonary vascular tone mediators, or screening for labeled afMSCs were performed at term (E22). Statistical comparisons were by Mann-Whitney U-test, nested ANOVA, and Wald test. Results: TRASCET led to significant downregulation of endothelial nitric oxide synthase and endothelin receptor-A expressions compared to both untreated and saline groups (both p < 0.001). TRASCET also led to a significant decrease in arteriole wall thickness compared to the untreated group (p < 0.001) but not the saline group (p = 0.180). Donor afMSCs were identified in the bone marrow and umbilical cord (p = 0.035 and 0.015, respectively, vs. plain luciferase controls). Conclusions: The effects of TRASCET in experimental CDH appear to be centered on the pulmonary vasculature and to derive from circulating donor cells.

Optimized cast components in the drive train of wind turbines and inner ring creep in the main bearing seat

Using large components made of nodular cast iron (GJS) in wind turbines enables the application of lightweight construction through the high degree of design freedom. Besides the sand-casting process, casting into a permanent metal mould, i.e. chill casting, leads to a finer microstructure and higher quasi-static mechanical properties as well as higher fatigue strength. Unfortunately, in present design methodologies specific fatigue data is only available for sand cast and not for chilled cast GJS. Thus, lightweight design strategies for large, chilled cast components are not achievable, which led to the publicly funded project “Gusswelle”. Based on material investigations of EN-GJS-400-18-LT chill cast, an optimized hollow rotor shaft is developed. The design process and the resulting shaft design are presented. The optimized hollow rotor shaft prototype will be tested on a full-scale test bench to validate the design methodology. The intended validation plan as well as the test bench setup is shown in this paper. Furthermore, the decreasing wall thickness influences the interference fit between main bearing and hollow rotor shaft. Thus, through the applied bending moment, inner ring creep is more probable to occur in the main bearing seat. The creeping behaviour is investigated with finite element simulations and a measuring method is presented.