bluuebunny/crossref_metadata_2025 huggingface dataset:
Behaviour of bolted lap joints in above-ground liquid-filled steel cylindrical tanks
Authors: Moslemi Mehdi , Kianoush M. Reza
Published: July 2021

Leakage is the main concern in steel bolted liquid tanks and past experience has indicated serviceability problems due to leakage, mainly from the joint locations, even in situations where the tank has only been subjected to an internal hydrostatic pressure. In this study, the performance of this type of construction was investigated using a detailed finite element (FE) analysis technique. Moreover, the validity of the American Water Works Association design practice in terms of the safe design of this type of structure at a wide range of service loads is evaluated through a parametric study. The FE analysis was performed in two stages using shell and solid elements in a three-dimensional ANSYS environment including the effect of geometric nonlinearity. The proposed FE model could estimating the behaviors such as capacity curve, yield/failure pattern, and the occurrence of ovalling and curling in bolted connections. In addition, the FE results were compared with experimental ones and found to be generally in good agreement. This study shows that a bolt arrangement chosen by design can efficiently improve the joint performance. Further, the use of a limited deformation criterion in the leak-resistant design of bolted lap joints in steel liquid containers is recommended.
Shadow cast and quasinormal modes in f(R) gravity model inspired by Yang–Mills field
Authors: Younesizadeh Younes , Liang Jennifer
Published: July 2021

In this paper, the null geodesic equations are computed in [Formula: see text] space–time dimensions [Y. Younesizadeh, A. A. Ahmad, A. H. Ahmed, F. Younesizadeh, Ann. Phys. 420, 168246 (2020)] by using the concept of symmetries and Hamilton–Jacobi equation and Carter separable method. With these null geodesics in hand, we evaluate the celestial coordinates (x, y) and the radius [Formula: see text] of the BH shadow and represent it graphically. In addition, we have shown that the peak of this energy slowly shifts to lower frequencies and its height decreases with the increase in the YM magnetic charge ([Formula: see text]) values and decrease in the [Formula: see text] parameter ([Formula: see text]) values. In addition, we have analyzed the concept of effective potential barrier by transforming the radial equation of motion into standard Schrodinger form. The most important result derived from this study is that the height of this potential increases with increase in the YM magnetic charge ([Formula: see text]) values. Then, we study the quasinormal modes (QNMs) of these 4D black holes. For this purpose, we use the WKB approximation method upto third-order corrections. We have shown the perturbation’s decay in corresponding diagrams when the YM magnetic charge ([Formula: see text]) values and the [Formula: see text] parameter ([Formula: see text]) values change.
Laminated design for the application of composite materials for ship radar mast
Authors: Yoon Sung Won , Park Chang Wook
Published: July 2021

The purpose of this study is to determine the correct estimation of laminated design for composite materials applied to a ship radar mast. Recently, as the IMO’s environmental regulations have been strengthened to increase the energy efficiency of ships, the IMO has also begun to consider operational economics such as energy reduction through lightening the hull. Demand for lighter weight technology using composite materials is increasing. Examples would include lightweight large structures using composite materials, composite materials replacing metal design parts, and polymer composite materials applicable to marine environments. Therefore, in this study, the properties of the material were analyzed using a simulation program to verify the applicability of the composite material for ship radar mast. In addition, the reliability of the simulation result was secured through Fiber/Matrix/Ply correction and the calculation of the laminate dynamics. The results provide basic properties (E33, G23, G13, [Formula: see text]23, [Formula: see text]13, S13, S23) for computer analysis other than mechanical properties derived experimentally.
Two-dimensional parabolic Dirac system in the presence of nonmagnetic and magnetic impurities
Authors: Wu Chen-Huan
Published: July 2021

We theoretically investigate the effect of the nonmagnetic and magnetic impurities to the 2D parabolic Dirac system. The induced charge density by the charged impurity is obtained by the linear response theory within the random phase approximation. We also calculate in-detail, the Ruderman–Kittel–Kasuya–Yosida (RKKY) interaction between two magnetic impurities placed within the 2D sheet of the Dirac materials with isotropic and anisotropic dispersion. For the anisotropic dispersion, the RKKY interaction is also anisotropic and related to the lattice parameters which can be obtained through the DFT calculation or the experiments. The features of the RKKY interaction also can be treated as a signature of the topological phase transition as well as the change of Berry curvature. Our results are also illuminating to the study of the static screening and the RKKY interaction of the isotropic or anisotropic 3D Dirac/Weyl semimetals or the 2D transition metal dichalcogenide family.
High-Frequency Mixed Rossby-Gravity Waves in the Mid-Troposphere Triggered Kerala Floods of 2018
Authors: Kiran S. R.
Published: July 2021

Kerala, the South-West coastal state of India, was ravaged by a series of floods during the South-West Monsoon of 2018. The season was marked by severely anomalous rainfall trends, with over 100 mm of departures from the mean daily precipitation in the northern districts of the State. Unlike previous works, this study not only documents the extreme event, but also identifies the tropical dynamics responsible for it. The synoptic disturbances of the tropical Pacific triggered high-frequency Mixed Rossby-Gravity (MRG) waves in the mid-troposphere during Boreal Summer, which meddled with the Monsoon trough, as it propagated westward from the east Equatorial Indian Ocean to the east coast of Africa. Interestingly, these equatorially-trapped waves were found to have teamed up with Madden–Julian Oscillations (MJO) to fuel deep convection in the tropics and caused heavy rainfall over Kerala in 2018.
A Comparison of Benson’s Outer Approximation Algorithm with an Extended Version of Multiobjective Simplex Algorithm
Authors: Nyiam Paschal B. , Salhi Abdellah
Published: July 2021

The multiple objective simplex algorithm and its variants work in the decision variable space to find the set of all efficient extreme points of multiple objective linear programming (MOLP). Other approaches to the problem find either the entire set of all efficient solutions or a subset of them and also return the corresponding objective values (nondominated points). This paper presents an extension of the multiobjective simplex algorithm (MSA) to generate the set of all nondominated points and no redundant ones. This extended version is compared to Benson’s outer approximation (BOA) algorithm that also computes the set of all nondominated points of the problem. Numerical results on nontrivial MOLP problems show that the total number of nondominated points returned by the extended MSA is the same as that returned by BOA for most of the problems considered.
A Pharmacokinetic Evaluation of a Pectin-Based Oral Multiparticulate Matrix Carrier of Carbamazepine
Authors: Amponsah Seth Kwabena , Yeboah Simon , Kukuia Kennedy Kwami Edem , N’guessan Benoit Banga , Adi-Dako Ofosua
Published: July 2021

Background. Carbamazepine is a drug used in the treatment of neurological disorders such as epilepsy. However, due to its erratic absorption, oral bioavailability is often poor. There is, therefore, the need to develop alternative formulations for carbamazepine with better pharmacokinetic characteristics. Aim. The aim of this study was to formulate an oral modified-release multiparticulate matrix of carbamazepine from cocoa pod husk (CPH) pectin and evaluate the pharmacokinetic profile of this formulation using in vitro and in vivo models. Methods. CPH pectin was extracted from cocoa pod husks with hot aqueous and citric acid solutions. Oral multiparticulate carbamazepine matrices were formulated from CPH pectin cross-linked with calcium. The formulation was evaluated for carbamazepine content and release profile in vitro. For in vivo pharmacokinetic profile estimation, rats were put into 4 groups of 5 animals each to receive carbamazepine multiparticulate matrix formulations A and B, carbamazepine powder, and Tegretol CR®. Animals in each group received 200 mg/kg of each drug via the oral route. Maximum plasma concentration

C

max

, area under the concentration-time curve (AUC), elimination rate constant

K

e

, and terminal half-life

t

1
/
2

of the formulations were estimated by noncompartmental analysis. Results. The pectin extraction from fresh cocoa pod husks using hot aqueous and citric acid solutions gave pectin yields of 9.63% and 11.54%, respectively. The drug content of carbamazepine in CPH pectin formulations A and B was 95% and 96%, respectively. There was controlled and sustained release of carbamazepine for both formulations A and B in vitro. AUC0⟶36 (176.20 ± 7.97 µg.h/mL),

C

max

(8.45 ± 0.71 μg/mL),

T

max

(12 ± 1.28 h), and

t

1
/
2

(13.75 ± 3.28 h) of formulation A showed a moderately enhanced and comparable pharmacokinetic profile to Tegretol CR® (AUC0⟶36: 155 ± 7.15 µg.h/mL,

C

max

: 8.24 ± 0.45 μg/mL,

T

max

: 8.0 ± 2.23 h, and

t

1
/
2

: 13.51 ± 2.87 h). Conclusion. Findings from the study suggest that formulations of CPH pectin had the potential to control and maintain therapeutic concentrations of carbamazepine in circulation over a period of time in the rat model.
Modeling the Effect of Binding Kinetics in Spatial Drug Distribution in the Brain
Authors: Kashaju Nelson , Kimathi Mark , Masanja Verdiana G.
Published: July 2021

A 3-dimensional mathematical model is developed to determine the effect of drug binding kinetics on the spatial distribution of a drug within the brain. The key components, namely, transport across the blood-brain barrier (BBB), drug distribution in the brain extracellular fluid (ECF), and drug binding kinetics are coupled with the bidirectional bulk flow of the brain ECF to enhance the visualization of drug concentration in the brain. The model is developed based on the cubical volume of a brain unit, which is a union of three subdomains: the brain ECF, the BBB, and the blood plasma. The model is a set of partial differential equations and the associated initial and boundary conditions through which the drug distribution process in the mentioned subdomains is described. Effects of drug binding kinetics are investigated by varying the binding parameter values for both nonspecific and specific binding sites. All variations of binding parameter values are discussed, and the results show the improved visualization of the effect of binding kinetics in the drug distribution within the brain. For more realistic visualization, we suggest incorporating more brain components that make up the large volume of the brain tissue.
The Optimal Rubbling Number of Paths, Cycles, and Grids
Authors: Xia Zheng-Jiang , Hong Zhen-Mu
Published: July 2021

A pebbling move on a graph G consists of the removal of two pebbles from one vertex and the placement of one pebble on an adjacent vertex. Rubbling is a version of pebbling where an additional move is allowed, which is also called the strict rubbling move. In this new move, one pebble each is removed from u and v adjacent to a vertex w, and one pebble is added on w. The rubbling number of a graph G is the smallest number m, such that one pebble can be moved to each vertex from every distribution with m pebbles. The optimal rubbling number of a graph G is the smallest number m, such that one pebble can be moved to each vertex from some distribution with m pebbles. In this paper, we give short proofs to determine the rubbling number of cycles and the optimal rubbling number of paths, cycles, and the grid P2 × Pn; moreover, we give an upper bound of the optimal rubbling number of Pm × Pn.
A Case of Acute Eosinophilic Leukemia with a Novel PHF6 Mutation
Authors: Lipof J. J. , Huselton E. J. , Zent C. S. , Evans A. , Zhang B. , Rothberg P. G. , Bennett J. M.
Published: July 2021

Acute eosinophilic leukemia (AEL) is a rare form of acute myeloid leukemia (AML) that requires prompt exclusion of reactive etiologies of eosinophilia and identification of an underlying acute myeloid neoplasm. Myeloid neoplasms with prominent eosinophilia often have rearrangements in the platelet-derived growth factor receptor

α

(PDGFRA) or

β

(PDGFRB) or are associated with core-binding factor AML. In this report, we describe a 35-year-old male presenting with chest discomfort and altered mental status, found to have marked leukocytosis with eosinophilic predominance and an elevated blast count. Bone marrow aspirate and biopsy findings were morphologically consistent with AEL. Fluorescence in situ hybridization (FISH) and standard karyotype analysis did not reveal any abnormalities, and mutation analysis using next generation sequencing (NGS) revealed a pathogenic mutation in PHF6. Cardiac work-up revealed findings suggestive of eosinophilic myocarditis. High-dose glucocorticoid therapy was initiated followed by standard intensive induction chemotherapy with cytarabine and idarubicin. He experienced a rapid reduction in peripheral blood eosinophil and blast count and was found to be in a complete remission at the time of his postinduction bone marrow examination. He underwent allogeneic stem cell transplantation with a matched sibling donor after consolidative high-dose cytarabine and remains in remission at the time of this report, 6 months following his initial diagnosis. The rarity of this condition has resulted in a paucity of data to guide management. Additional studies are needed to better characterize this entity and inform optimal management strategies to attain a long-term sustained remission in these patients.
The Effects of Yoga on Patients with Parkinson’s Disease: A Meta-Analysis of Randomized Controlled Trials
Authors: Ban Mengke , Yue Xuejing , Dou Pengyu , Zhang Ping
Published: July 2021

Background and Purpose. The manifestations of motor and nonmotor dysfunctions in Parkinson’s disease (PD), which are intimately connected, have been shown to reduce quality of life (QoL). It has been demonstrated that yoga could benefit PD patients. However, there was no consensus on the impact of yoga on PD. This meta-analysis is aimed at investigating the effects of yoga intervention on motor function, nonmotor function, and QoL in patients with PD. Methods. A meta-analysis was conducted by systematically searching PubMed, Embase, and Cochrane Library databases till August 2020 for studies published in English. The reference lists of eligible studies were also searched. The motor symptoms (UPDRS-Part III), balance function (BBS and BESTest), functional mobility (TUG), anxiety (HADS and BAI), depression (HADS and BDI), and the quality of life (PDQ-39 and PDQ-8) were the primary evaluation indexes. Results. Ten studies including 359 participants were included in this meta-analysis. The pooled results showed significant difference between the yoga training group and the control group. Patients in the yoga training group had better functional outcomes in terms of motor status (

MD
=
−
5.64

; 95% CI, -8.57 to -2.7), balance function (

SMD
=
0.42

; 95% CI, 0.08 to 0.77), functional mobility (

MD
=
−
1.71

; 95% CI, -2.58 to -0.84), anxiety scale scores (

SMD
=
−
0.72

; 95% CI, -1.01 to -0.43), depression scale scores (

SMD
=
−
0.92

; 95% CI, -1.22 to -0.62), and QoL (

SMD
=
−
0.54

; 95% CI, -0.97 to -0.11). Conclusion. Our pooled results showed the benefits of yoga in improving motor function, balance, functional mobility, reducing anxiety and depression, and increasing QoL in PD patients.
Evaluation of the Clinical, Child, and Parental Satisfaction with Zirconia Crowns in Maxillary Primary Incisors: A Systematic Review
Authors: Hamrah Mohammad Hassan , Mokhtari Saeedeh , Hosseini Zahra , Khosrozadeh Maryam , Hosseini Sepideh , Ghafary Elaha Somaya , Hamrah Mohammad Hussain , Narges tavana
Published: July 2021

Background. With the increasing demand for aesthetics in children and their parents, the treatment of decayed primary anterior teeth is one of the biggest challenges in pediatric dentistry. Zirconia crowns have provided a treatment alternative to address the aesthetic concerns and ease of placement of extracoronal restorations on primary anterior teeth. Methods. The electronic databases including PubMed, Scopus, Google Scholar, and Embase were searched on articles published between January 2010 and January 2021. Studies relating to evaluating the clinical success and satisfaction of both parents and children about zirconia crowns in maxillary primary incisors were reviewed. Results. Nine studies met the criteria for final inclusion. Findings from these studies showed that parental and child satisfaction with zirconia crowns is high with clinically acceptable restorations in the maxillary primary incisors. Conclusion. Parental and child satisfaction with zirconia crowns is high with clinically acceptable restorations in the maxillary primary incisors. In addition, larger sample sizes and longer follow-ups are required in future studies.
Receiver Operator Characteristics (ROC) Analysis of Real-Time Shear Wave Elastography Information Health Monitoring in Liver Fibrosis with Chronic Hepatitis B Virus Infection
Authors: Zhao Zhexia , Chen Xiaoyan , Zhang Yanxia , Song Qian , Xue Jiping , Kang Chunsong
Published: July 2021

To investigate the effectiveness of shear-wave elastography (SWE) based on e-health in diagnosing liver fibrosis in patients infected with hepatitis B virus (HBV) and provide theoretical basis for early diagnosis and treatment of patients with chronic HBV infection, in this study, 73 patients with chronic HBV infection who underwent e-health SWE examination were divided into chronic hepatitis B group (51 cases) and hepatitis B cirrhosis group (22 cases), and another 20 healthy volunteers were introduced as control. The contents of second liver two half-and-half, hyaluronic acid (HA) of liver fibrosis, laminin (LN), pAUVollagen III N terminal peptide (PIII NP), collage type IV (CIV), and HBV-DNA were detected. SWE was used to measure the elastic modulus in the S2 and S3 segments of the left outer lobe of the liver, S4 segment of the left inner lobe of the liver, S5 and S8 segments of the right anterior lobe of the liver, and S6 and S7 segments of the right posterior lobe of the liver. Finally, the correlations between the four examination results of liver fibrosis and the elastic modulus values were compared, and the receiver operator characteristic curve (ROC) for SWE technical diagnosis was drawn. The results showed that there was no significant difference in HBV-DNA content between the two groups (

P
>
0.05

); the contents of alanine transaminase (ALT) and aspartate aminotransferase (AST) in the blood of chronic hepatitis B group were significantly higher than those in the liver cirrhosis group (

P
<
0.05

); HA, PIII NP, and CIV contents were significantly lower than the liver cirrhosis group (

P
<
0.05

); the success rates of SWE detection in S5 and S6 segments of the two groups were 100.00%, and the elastic modulus of the hepatitis B cirrhosis group was significantly higher than that of the chronic hepatitis B group (

P
<
0.05

); correlation results showed HA, PIII NP, and CIV of two groups of patients and elastic modulus value in S5 and S6 segments showed positive correlation (

P
<
0.05

); ROC curve analysis showed that AUC (area under the curve) was 0.866, the sensitivity was 89.59%, and the specificity was 76.49%, which indicated that the liver elastic modulus value measured by e-health SWE technology can quantitatively show liver fibrosis in patients with chronic HBV infection, and its application in the diagnosis of clinical liver fibrosis was real and feasible.
Axonal Injury with Persistent Neuropathy following Popliteal Nerve Block for Cheilectomy Surgery
Authors: Kuijpers Y. A. M. , Setz J. M. , Khemlani-Houthoff K.
Published: July 2021

Peripheral nerve blocks are often used for foot and ankle surgery. The occurrence of persistent neurological symptoms thereafter is very rare. Preventive strategies pose no guarantee and uncovering true etiology is often complicated. We discuss a case in which a young, healthy patient developed nerve damage after an uneventful popliteal block and cheilectomy. Nerve conduction studies revealed axonal injury in the distribution area of the sciatic nerve. The neurological symptoms persisted for more than 12 months, emotionally affecting the patient greatly. Patients will primarily report to the orthopedic surgeon, for whom cooperation with anaesthesia and neurology is of importance. Anesthetic involvement probably improves patient satisfaction during complication management.
A New Wideband Circularly Polarized Dielectric Resonator Antenna Loaded with Strips
Authors: Hao Lichao , Wang Hao , Li Bo , Yin Wenting
Published: July 2021

This paper proposes a novel wideband circularly polarized (CP) dielectric resonator antenna (DRA) loaded with strips. The CP DRA comprises a circular DR, two pairs of driven L-like DR strips with different lengths, and a square ground-plane. To couple the electromagnetic energy to circular DR, an orthogonal cross-slot is used, and a stepped microstrip-line is also used to adjust the impedance matching. Influenced by the concept of deformed DR, two pairs of L-like DR strips of different lengths are inserted into the circular DR as part of the driven element to excite a new axial ratio (AR) resonant point. An antenna prototype is simulated, manufactured, and measured to validate the unique design. The measured results show that the designed antenna has broadband characteristic with a −10 dB IBW of 54% (1.91–3.32 GHz) and 3 dB ARBW of 42.1% (2.10–3.22 GHz).
Analysis of One‐Dimensional Consolidation for Unsaturated Soils under Piecewise Cyclic Loading
Authors: Huang Yuanchun , Shen Sidong , Wang Lei , Li Tianyi , Fu Xianlei
Published: July 2021

This paper studies the one‐dimensional (1D) consolidation behavior for unsaturated stratum subjected to piecewise cyclic loading. Combined with the widely accepted consolidation theory of unsaturated soils, a semianalytical method was employed to investigate the consolidation of unsaturated foundation considering piecewise cyclic loading in the Laplace domain. Furthermore, the reduced solutions were produced to perform the verification work accompanied by the results in the existing literature. Finally, a case study was conducted to explore the consolidation characteristics under piecewise cyclic loading (i.e., triangular and trapezoidal cyclic loadings). Parametric studies were carried out by variations of excess pore pressures and settlement against the ratio of air‐water permeability coefficients, depth, and loading parameters. The research proposed in this paper can provide theoretical basis for the ground treatment of unsaturated soils, especially for rationally accelerating consolidation or avoiding sudden settlement.
Dorit Rabinyan: Comentários e Reflexões - Encontros de Literatura Hebraica (Grupo de Leitura)
Authors: Langer Eliana , Forner Naamá Silverman , Krengel Sara
Published: July 2021

Iniciamos este artigo com comentários gerais sobre a atividade de grupos de leitura e sua possível contribuição para a análise e pesquisa literárias. Em seguida, trazemos reflexões de um grupo de leitura que se encontra mensalmente para falar em hebraico sobre obras da literatura hebraica. Dois encontros foram dedicados aos romances O beco das amendoeiras em Omaridjan (1995) e Nossos Casamentos (1999), cuja autora é Dorit Rabinyan. As ideias, abordagens e análises do grupo foram reunidas, editadas e formuladas no texto abaixo. Para finalizar, acrescentamos alguns comentários acerca do último romance da autora, Cerca viva, publicado recentemente (2014).
Homens da Montanha: Cristãos Novos e a Ocupação do Interior Brasileiro
Authors: Tonello Levy Daniela
Published: July 2021

Judeus Sefaraditas, descendentes dos convertidos em 1497, foram os pioneiros na descoberta do ouro e diamantes na América portuguesa. A instituição do Tribunal do Santo Ofício da Inquisição, trouxe drásticas consequências para a vida Ibérica, que a longo prazo arruinaram o comércio português, fazendo emigrar do Reino os mais prestigiosos elementos, prejudicando por muitos anos a produção nacional, destruindo famílias e negócios. A cultura judaica, florescente na Península Ibérica até o século XV, apagou-se, e Portugal submergiu nas trevas da ignorância. Em São Paulo, os cristãos novos estiveram entre os desbravadores do sertão brasileiro, ultrapassando os limites do Tratado de Tordesilhas. Os habitantes da então inóspita Vila de São Paulo de Piratininga eram considerados inimigos da Espanha, por suas incursões ao sertão em busca de oportunidades econômicas. No interior, lutaram contra às Missões jesuíticas, a vida selvagem, fome, sede e finalmente se tornaram os primeiros a encontrar ouro no Brasil.  Foram os primeiros a abrir estradas e fundar as vilas do ouro. Um marrano, Garcia Rodrigues Paes, foi o responsável pela construção do “Caminho do comércio” que encurtava a distância entre o Rio de janeiro, principal porto e a Vila de Ouro Preto. Os sefaraditas acreditavam estar seguros, nas montanhas e no interior do Brasil, mas a Inquisição formou uma rede de espiões encarregados de espionar e prender os cristãos novos.
Más allá de las lenguas nacionales: Interlengua y vocalizaciones de la migración
Authors: Cid Alarcón Jorge Ignacio
Published: July 2021

Este artículo reflexiona sobre cómo la poesía de NéstorPerlongher integra en su lenguaje elementos heteroglósicos y lasconsecuencias que éstos, en tanto que gestos de inobservanciagramatical, tienen en el plano simbólico y político. Obras comoAlambres de Néstor Perlongher (escritos mezclando portuñol,lunfardo y gauchesca) parecen rebelarse contra la forma en que lagramática, más allá de regular la correcta realización de un idioma,instituiría un dispositivo de control de la emotividad de los individuosa través del establecimiento de formas de expresión homogeneizantespropendidas por la lengua materna en su manifestación estándar.En este contexto, la utilización de mecanismos heteroglósicos enla creación literaria permite al poeta combatir la matrificación dela subjetividad que comportan las lenguas de Estado, instaurandola desestabilización de sus paradigmas fronterizos a través de latransgresión de sus estatutos idiomáticos.
A Força do Povo: experiência atual e fonte de esperança
Authors: Caldas Eduardo de Lima
Published: July 2021

Obra: A Força do Povo: democracia participativa em Lages
Autores: Marcio Moreira Alves
Cidade: São Paulo
Editora: Brasiliense
Ano: 1980
Páginas: 150
ISBN: 19824150
Abstract 403: Tracking the Migration of Porcine Mesenchymal Stem Cells with the MRI Contrast Agent Ferex in an AAA Model
Authors: Tadros Rami , Rawal Bhakti , Briley-Saebo Karen , O’Connor David , Han Dan , Hajjar Roger , Fayad Zahi , Marin Michael , Faries Peter
Published: July 2021

Introduction:
Mesenchymal stem cells (MSC) are being investigated in porcine abdominal aortic aneurysm (PAAA) models for their repair potential. This study uses MSCs labeled with the MRI contrast agent Ferex to non-invasively evaluate MSC migration in-vivo.

Methods:
MSCs from 6 pigs were isolated from bone marrow via Ficoll Paque separation and expanded in culture. Using a Lentiviral vector, MSC from all 6 pigs were transfected with green florescent protein (GFP). MSCs from 4 of these pigs were also labeled with 200μg/ml Ferex using Poly-L-Lysine and then analyzed for Ferex uptake and viability. Preservation of the MSC phenotype was confirmed using flow cytometry by detecting positive CD90 and negative CD45 and CD117. Transmission electron microscopy established that Ferex localized to lysosomes. MSCs were then injected into the adventitia of the PAAA. In-vivo MRI was performed using multiple echo gradient echo sequences. Effective transverse relaxation times (T2* values) were calculated on a pixel-by-pixel basis as a function of time post cell transplantation.

Results:
Ferex labeled MSCs were visible post transplantation at 4, 11, 15 and 21 days using MRI. The MRI signal void (decreased T2* values) correlated with the presence of Ferex within the PAAA. This signal loss progressively expanded circumferentially at each study interval representing cellular movement. MSC migration and localization were confirmed with GFP visualization on fluorescence microscopy and immunohistochemistry. In-vivo MRI signals also correlate with iron deposition on Perl’s stain.

Conclusion:
Ferex can be used as an in-vivo tracking agent of MSCs in PAAA models.
Abstract 472: Calcium Current by Somatostatin Leads to Vasoconstriction in Rabbit Cerebral Artery
Authors: Kim Nari , Ko Kyung Soo , Rhee Byoung Doo , Han Jin
Published: July 2021

Somatostatin-containing neurons have a widespread distribution in the central nervous system. Moreover, the level of somatostatin in bloody cerebrospinal fluid and plasma is elevated patients with stroke.

However, there is little evidence to support that somatostatin is a possible factor of vasopasm after stroke. This experiment was to undertaken to evaluate the effects of somatostatin on Ca
2+
currents using the whole-cell voltage-clamp techniques and on Ca
2+
transients using whole-cell fluorescence in cerebral arteries of the rabbit.

During rectangular pulses, both peak and steady-state Ca
2+
currents

were significantly increased by the application of somatostatin. Somatostatin had little effect on the steady-state activation kinetics, however, significant effect on the time constants for current decay. τ increased monotonically with voltage and was slightly slower in somatostatin-treated cells between 0 and +30 mV. The half maximal concentration of somatostatin was 8.5±1.3 pM in dose-response relation. Moreover, Ca
2+
transients by somatostatin were significantly increased in cells.

From these results, the activation of Ca
2+
currents by somatostatin could be involved in pathogenesis of vasospasm after stroke.
Abstract 57: 12-Lipoxygenase is a Critical Enzyme Regulating FcyRIIa-Mediated Platelet Activation
Authors: Yeung Jennifer , Tourdot Benjamin , Holman Theodore R , McKenzie Steven E , Holinstat Michael
Published: July 2021

Introduction:
FcγRIIa plays a key role in platelet activation mediated by immune complexes containing IgG and platelet factor 4 (PF4) bound to heparin. One of the primary mechanisms by which FcγRIIa mediates it effects in the platelet is through its ITAM motif. 12-lipoxygenase (12-LOX) has recently been shown to play an important role in regulation of platelet function through GPVI, which also signals in part through an ITAM motif. We therefore hypothesize that 12-LOX can play an important role in regulation of FcγRIIa-mediated platelet activation resulting in aggregation and thrombosis. Identifying the importance of this regulatory interaction is essential for understanding the role of 12-LOX in regulation of hemostasis and thrombosis, and identifying a possible target for prevention of FcγRIIa -induced platelet activation.

Objectives:
Determine the requirement of 12-LOX activation in FcγRIIa -mediated platelet activation and identify the underlying mechanism by which 12-LOX activation regulates FcγRIIa.

Methods:
FcγRIIa-mediated Platelet aggregation was measured in washed human platelets and mouse platelets in the presence of a 12-LOX inhibitor or in FcγRIIa
+/+
mice crossed with 12-LOX
-/-
mice. PLCγ and PKC activation were measured in the absence of 12-LOX activity. Additionally, Rap1, calcium, and αIIbβ3 activity was measured in the presence or absence of 12-LOX activity following stimulation of FcγRIIa with CD9 or goat anti-mouse IV.3 antibody (IV.3).

Results:
Both human and FcγRIIa
+/+
mouse platelets were able to fully aggregate following stimulation with CD9 or IV.3. Pharmacological inhibition of 12-LOX or absence of 12-LOX significantly delayed and attenuated platelet aggregation. Additionally, PLCγ, calcium, Rap1 and activation of αIIbβ3 were inhibited.

Conclusions:
These observations support our hypothesis that 12-LOX is an essential enzyme in the regulation of FcγRIIa-mediated platelet activation. Further investigation of this regulatory pathway will help to confirm 12-LOX as a viable target for inhibition of FcγRIIa and other ITAM-mediated platelet activation.
Abstract 571: A Novel High-Throughput Whole Blood Immuno-Counting Assay is Useful in the Assessment of Platelet Responses to Antiplatelet Therapy
Authors: Lordkipanidze Marie , Dovlatova Natalia , Algahtani Mohammad , Lundberg Martina H , Warner Timothy D , Fox Susan C , Watson Steve P
Published: July 2021

Background:
The current gold standard in platelet function testing, light transmission aggregometry, is time- and labor-intensive, and uses platelet-rich plasma which makes it sub-optimal for high throughput testing. In order to reduce blood manipulation prior to platelet function testing and to study multiple platelet activation pathways simultaneously, we have developed a 96-well plate-based assay carried out in whole blood, where aggregation is measured as a decrease in the number of fluorescently-labeled single platelets by flow cytometry.

Aim:
To investigate whether a 96-well plate-based whole blood assay can be used to assess platelet function.

Methods:
Platelet function in response to 5 concentrations of lyophilized arachidonic acid (AA), ADP, collagen, epinephrine, TRAP, U46619, and ristocetin, was assessed in healthy volunteers (n=20) to establish normal ranges. The effect of antiplatelet drugs was assessed in vitro by incubation with aspirin (100 μM), cangrelor (1 μM) or both (n=20), and in patients on dual antiplatelet therapy (n=20). After addition of 40 μl of whole blood per well, the plate was shaken for 5 min at 1000 rpm at 37°C; a fixative solution (Platelet Solutions, Nottingham) was applied to stop platelet aggregation and allow analysis in a central laboratory. Fixed whole blood samples (stable for up to 9 days) were labeled with FITC-conjugated CD42a and assessed by flow cytometry. Aggregation was calculated as (Platelet count in vehicle-treated sample - Platelet count in agonist-stimulated sample) / Platelet count in vehicle-treated sample x 100.

Results:
Dose-response curves were readily assessable for all agonists and intra-individual variability was minimal in healthy volunteers (CV<10%). In vitro addition of aspirin alone resulted in inhibition of AA- and collagen-induced aggregation, whereas cangrelor induced a shift in dose-response to most agonists in addition to profound inhibition of ADP responses. In patients on dual antiplatelet therapy, the pattern of response was consistent with the results obtained with in vitro agents.

Conclusions:
A 96-well plate-based whole blood assay with a minimal blood volume requirement (<2 ml) could be used to provide a global portrait of platelet responses to antiplatelet agents.
Abstract 574: Regulation of Vascular Smooth Muscle Cells Phenotype by the Adhesion of Platelets to Endothelial Cells
Authors: Luo Mao , Zeng Min , Ren Meiping , Li Rong , Deng Xin , Chen Ni , Yang Yan , Wu Jianbo
Published: July 2021

Objective:
Platelets can regulate endothelial cell genes expression through their adhesion to the subendothelium in response to vascular injury. Recently it has been reported that some endothelial cells (ECs)-secreted genes can modulate vascular smooth muscle cells (VSMCs) phenotypic transformation by ECs/VSMCs co-culture. However, little is known about the effects of platelets adhesion to ECs interaction on VSMCs phenotype. In this study, we investigated the role of some genes secreted by platelets adhesion to EC in regulating SMC phenotypic transformation.

Methods and Results:
By Q-RT-PCR, expression of PAI-1, MMP-2 and MMP-9 were up-regulated in ECs after platelets adhesion to ECs comparing to ECs monoculture alone. In migration (scratch) and proliferation (CCK-8) assays, platelets adhesion to ECs increased EC migration-promoting activity and proliferative activity. After adhesion of platelets to ECs/VSMCs co-culture, expression of VSMCs contractile apparatus SM-MHC, Smoothelin-B, SMA and SM22a were significantly decreased comparing to ECs/VSMCs co-culture by Q-RT-PCR, but decreasing slightly in adhesion with platelets from type 2 diabetes. Conversely, it increased the expression of synthetic marker Smemb, CCND-1, CCND-2. Further analysis found that platelets adhesion to ECs/VSMCs co-culture significantly increased VSMCs migration-promoting activity and proliferative activity. In Gelatin Zymography assays, there were high levels of MMP-2 and MMP-9 after adhesion of platelets to ECs/VSMCs co-culture comparing to ECs/VSMCs co-culture alone.

Conclusion:
These results offer important insights into the mechanisms controlling phenotypic modulation of VSMCs by platelets adhesion to ECs, and help to explain the effects of platelets-ECs-VSMCs interaction on VSMCs contractile/synthetic, migration, and proliferation, suggesting that the adhesion of platelets to ECs is a key process in regulating phenotypic switch of VSMCs.
Abstract 583: Characterization of Cell Membrane Microdomains Facilitating HDL Biogenesis
Authors: Choi Hong , Ruel Isabelle , Wang Rui Hao Leo , Genest Jacques
Published: July 2021

High-density lipoprotein (HDL) particles, generated in the process of removing excess cellular cholesterol, play crucial roles in maintaining cholesterol homeostasis in arterial cells and in protecting the cardiovascular system from the development of atherosclerosis. Cholesterol-loaded cells increase their binding capacity to the HDL scaffolding protein, apolipoprotein A-I (ApoA-I), however, cell surface factors necessary for ApoA-I binding remains to be elucidated. To characterize cell membrane microdomains interacting with ApoA-I, primary human skin fibroblasts were incubated with ApoA-I for 1h at 4°C. After linking protein-protein interactions with a membrane-impermeable crosslinker, DTSSP, cells were subjected to homogenization. The cell homogenate was separated by a discontinuous sucrose gradient centrifugation and ten fractions were collected. ApoA-I-associated cell membrane fraction was located by immunoblotting for ApoA-I and organelle markers. Membrane-containing fractions were fragmented using sonication prior to immunoprecipitation of ApoA-I-associated microdomains using an anti-ApoA-I antibody. Major lipid classes present in the microdomains are phosphatidylcholine, phosphatidylserine, sphingomyelin and cholesterol. Two cell membrane proteins, caveolin and ABCA1, were excluded from the microdomains. These data suggest that ApoA-I bind to cholesterol-rich cell surface microdomains that are different from ABCA1 and caveolae domains. LC-MS/MS analysis identified the presence of 26 proteins in the microdomains. Among these, several desmosomal proteins, lipid binding proteins and protease inhibitors were identified. Overall, our results suggest that the initial binding of ApoA-I to cell surface occurs on the lateral sides of cell membranes where desmosomal proteins provide a binding site for ApoA-I, and that lipid binding proteins facilitate lipidation of ApoA-I while protease inhibitors protect ApoA-I and related proteins from degradation. In conclusion, we established a new method to isolate cell membrane microdomains interacting with ApoA-I. Using this method, we found that ApoA-I associates with desmosomal proteins for the formation of HDL.
Abstract 186: Novel Secondary Multifocal No-Reflow Phenomenon Associated with Activated Leukocyte-induced Microcirculatory Obstruction
Authors: Chang Wei-Tien , Lu Hsueh-Han , Liao Ian
Published: July 2021

Background:
No-reflow may occur early after reperfusion of ischemic tissues. In a rat model of hepatic ischemia and reperfusion (IR), delayed multifocal no-reflow was observed hours after initial restoration of circulation. We herein sought to characterize this novel phenomenon and investigate its underlying pathophysiological mechanism.

Methods:
Hepatic IR of male wistar rats was induced by clamping hepatic artery and portal vein for 60 min, followed by release of the clamp for reperfusion. Intravital optical microscopy was employed to image microcirculation (FITC-dextran), cellular hypoxia-reoxygenation (autofluorescence of mitochondrial flavoproteins), extracellular DNA (propidium iodide, PI) and the interactions among leukocytes, platelets and endothelium.

Results:
Multifocal no-reflow was observed in vivo at the early stage of reperfusion revealed by no recovery of microcirculation and cellular autofluorescence. Interestingly, such no-reflow phenomenon recurred sporadically and remittently about 3 h after initial restoration of circulation. This novel secondary no-reflow was associated with recurrent microcirculatory obstruction caused by stagnation of blood cells. Such obstruction was triggered by activated leukocytes as evidenced by their adhesion with platelets and migration along endothelium. Extracellular DNA near the obstructed sinusoids indicates involvement of neutrophil-extracellular traps (NET).

Conclusions:
Secondary multifocal no-reflow may occur hours after initial reperfusion. With activated leukocytes and NET playing key roles, the pathogenic mechanism differs distinctly from that of immediate no-reflow and may implicate alternative targets for therapeutic interventions.
Abstract 594: Selective Inhibition Of Lipoprotein-associated Phospholipase A
2
Attenuates Markers Of Plaque Vulnerability In Humans
Authors: Shi Yi , Zalewski Andrew , Macphee Colin , Dawson Michelle
Published: July 2021

Background:
Lp-PLA
2
, an emerging marker of CV risk, generates products of oxidized LDL that may contribute to inflammation and apoptosis. Although Lp-PLA
2
is highly expressed in thin-cap fibroatheroma and ruptured plaques, its role in mediating lesion vulnerability remains unknown.

Material and Methods:
Patients were randomized to receive placebo or the selective Lp-PLA
2
inhibitor, darapladib, (40 or 80 mg po) for 14 days prior to carotid endartherectomy. In the post hoc analysis, caspase activities were measured in carotid plaques (colorimetric assays: AU/mg of protein) and correlated with inhibition of Lp-PLA
2
activity in plasma (radiometric assay) using Spearman’s rank method.

Results:
Caspase-8 (initiator) and -3 (effector) activities were measured as the index of apoptosis in carotid atheroma specimens. In the validation study, carotid atheroma (n=10) exhibited augmented levels of caspase activities compared to non-diseased vessels (n=8) (caspase-8: 4.74±0.3 vs 2.59±0.2; caspase-3: 10.2±0.9 vs 4.15±0.4 p<0.001). Next, caspase-8 (n=39) and -3 (n=59) were measured in plaque samples derived from the dose-ranging study with darapladib. In patients treated with darapladib, caspase-8 activity within the plaques was significantly reduced [placebo: 4.66±0.48; 40 mg: 3.4±0.4, NS; 80 mg: 3.0±0.52, p=0.042 versus placebo (ANOVA with Bonferroni adjustment)]. Similarly, downstream caspase-3 was also decreased in the high dose group (placebo: 11.8±0.84; 40 mg: 10.4±0.88, NS; 80 mg: 6.5±1.0 p=0.0004 versus placebo). To further explore the relationship between Lp-PLA
2
activity and markers of apoptosis, plaque caspase activity was correlated with Lp-PLA
2
inhibition in plasma. Plaque caspase-8 and -3 correlated with inhibition of Lp-PLA
2
activity in plasma (caspase-8: r=-0.34, p=0.039; caspase-3: r=−0.51, p<0.0001).

Conclusions:
Inhibition of Lp-PLA
2
reduced activity of proapoptotic caspases in human atheroma. The results suggest that Lp-PLA
2
inhibition may attenuate noxious effects of oxidized LDL and promote lesion stabilization in high risk patients.
Abstract 710: Notch1 Receptor Enhances Myocyte Differentiation of Cardiac Progenitor Cells and Myocardial Regeneration After Infarction
Authors: Boni Alessandro , Nascimbene Angelo , Siggins Robert , Urbanek Konrad , Amano Katsuya , Delucchi Francesca , Yasuzawa-Amano Saori , LeCapitaine Nicole , Trofimova Irina , Di Marco Andrea , Vitale Serena , Small Narissa , Mosna Federico , Gonzalez Arantxa , Rimoldi Ornella , Kajstura Jan , Anversa Piero , Leri Annarosa
Published: July 2021

Cardiac progenitor cells (CPCs) have been identified in the adult heart. However, the molecular mechanisms involved in the commitment of CPCs to the myocyte lineage remain to be determined. Notch-1 is a transmembrane receptor activated by the DSL family of ligands which include Jagged1 and Delta-4. Upon ligand binding, the activated receptor undergoes cleavage by γ-secretase, and its intracellular portion (Notch intracellular domain, NICD) is released, translocates to the nucleus and exerts its function as a transcriptional regulator. The objective of this study was to determine whether the components of the Notch pathway are present in the CPCs of the adult mammalian heart and whether activation of the Notch-1 receptor promotes the differentiation of CPCs into myocytes. For this purpose, c-kit-positive CPCs were isolated from the mouse heart and analyzed by FACS and immunocytochemistry. Notch-1 receptor was detected in ~50% of c-kit-positive CPCs. CPCs were then plated on culture dishes coated with immobilized Jagged1 or Delta-4 and maintained in low-serum medium. Additional groups of cells were similarly exposed to the ligands but were also treated with γ-secretase inhibitor. After 5 days in culture, the number of CPCs was markedly lower in the presence of the Notch ligands and significantly higher in the presence of the γ-secretase inhibitor. After 8 days in culture, cells became confluent and did not express any longer c-kit. With respect to cells treated with the γ-secretase inhibitor, exposure to Jagged1 and Delta-4 resulted respectively in a 10-fold and 20-fold increase in the fraction of CPCs positive for Nkx2.5. These findings were consistent with a positive effect of Notch on CPC differentiation and Nkx2.5 upregulation. To establish whether Notch influenced cardiomyogenesis in vivo, infarcted mice were treated for 11 days with the γ-secretase inhibitor. The regenerative response of the infarcted heart, defined by the percentage of BrdU-positive myocytes distributed in the border zone, was 50% lower in animals that received the γ-secretase inhibitor. Thus, Notch1 modulates CPC differentiation in vitro and myocardial regeneration in vivo after infarction.
Abstract 186: Reduction Of High density lipoprotein Cholesterol After Successfull Dietary Intervention Is Not Accompanied By A Change In Reverse Cholesterol Transport
Authors: Poledne Rudolf
Published: July 2021

Substitution of dietary saturated fat by unsaturated fat and the reduction of dietary cholesterol intake leads to a decrease of LDL cholesterol concentration accompanied usually by a decrease of HDL cholesterol.

Method: 18 young male volunteers were fed for 4 weeks either a high cholesterol saturated fat diet or low cholesterol and unsaturated fat diet in crossover design. At the end of both experimental periods, the lipoprotein concentration was determined. In addition, the reverse cholesterol transport from
14
C cholesterol labeled macrophages in tissue cultures was analyzed. Reverse cholesterol transport was calculated as the percentage of radioactivity released from pre-labeled cells to incubation media with serum of each individuals.

Results: Highly significant decrease of LDL cholesterol after the unsaturated fat diet was accompanied by a significant decrease of the HDL cholesterol from 1.25 mmol/l to 1.05 mmol/l. Reverse cholesterol transport did not significantly change when the data of high cholesterol saturated fat diet (9.97 ± 1.45) and low cholesterol unsaturated fat diet (9.53 ± 1.41) were compared. There was no correlation between data of the decrease of HDL cholesterol concentration and change in reverse cholesterol transport.

Conclusion: We conclude that dietary treatment by hypocholesterolemic diet accompanied by a reduction of HDL cholesterol does not lead to the decrease in reverse cholesterol transport.