Search results for: vascular smooth muscle cell
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4946

Search results for: vascular smooth muscle cell

4736 MRI R2* of Liver in an Animal Model

Authors: Chiung-Yun Chang, Po-Chou Chen, Jiun-Shiang Tzeng, Ka-Wai Mac, Chia-Chi Hsiao, Jo-Chi Jao

Abstract:

This study aimed to measure R2* relaxation rates in the liver of New Zealand White (NZW) rabbits. R2* relaxation rate has been widely used in various hepatic diseases for iron overload by quantifying iron contents in liver. R2* relaxation rate is defined as the reciprocal of T2* relaxation time and mainly depends on the composition of tissue. Different tissues would have different R2* relaxation rates. The signal intensity decay in Magnetic resonance imaging (MRI) may be characterized by R2* relaxation rates. In this study, a 1.5T GE Signa HDxt whole body MR scanner equipped with an 8-channel high resolution knee coil was used to observe R2* values in NZW rabbit’s liver and muscle. Eight healthy NZW rabbits weighted 2 ~ 2.5 kg were recruited. After anesthesia using Zoletil 50 and Rompun 2% mixture, the abdomen of rabbit was landmarked at the center of knee coil to perform 3-plane localizer scan using fast spoiled gradient echo (FSPGR) pulse sequence. Afterward, multi-planar fast gradient echo (MFGR) scans were performed with 8 various echo times (TEs) (2/4/6/8/10/12/14/16 ms) to acquire images for R2* calculations. Regions of interest (ROIs) at liver and muscle were measured using Advantage workstation. Finally, the R2* was obtained by a linear regression of ln(SI) on TE. The results showed that the longer the echo time, the smaller the signal intensity. The R2* values of liver and muscle were 44.8  10.9 s-1 and 37.4  9.5 s-1, respectively. It implies that the iron concentration of liver is higher than that of muscle. In conclusion, R2* is correlated with iron contents in tissue. The correlations between R2* and iron content in NZW rabbit might be valuable for further exploration.

Keywords: liver, magnetic resonance imaging, muscle, R2* relaxation rate

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4735 Hemodialysis Technique in a Diabetic Population

Authors: Daniel Thompson, Sophie Cerutti, Muhammad Peerbux, Hansraj Bookun

Abstract:

Introduction: Diabetic nephropathy is the leading cause end stage renal failure in Australia, responsible for 36% of cases. Patients who require dialysis may be suitable for haemodialysis through an arteriovenous fistula (AVF), and preoperatively careful planning is required to select suitable vessels for a long-lasting fistula that provides suitable dialysis access. Due to high levels of vascular disease in diabetic patients, we sought to investigate whether there is a difference in the types of autologous AVFs created for diabetic patients in renal failure compared to their non-diabetic counterparts. Method: Data was collected from the Australasian Vascular Audit, for all vascular surgery completed at St. Vincent’s Hospital Melbourne between 2011-2020. Patients were selected by operative type, creation of AVF, and compared in two groups, diabetic patients and patients without diabetes. Chi-squared test was utilised to determine significance. Results: Data analysis is ongoing and will be complete with updated abstract in time for the conference. Discussion: Diabetic nephropathy is the cause for roughly a third of end stage renal failure in Australia. Diabetic patients present with a unique set of challenges when it comes to dialysis access due to increased risk of peripheral vascular disease and arterial calcification. Care must be taken in the creation of fistulas to minimise complications and increase the chance of long-lasting access. Our study investigates the difference in autologous AVFs between diabetics and non-diabetics, and results may be used to influence location of fistula creation. Further research may be used to investigate patency rates of fistulas in diabetics vs non-diabetics which would further influence treatment decisions.

Keywords: dialysis, diabetes, renal access, fistula

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4734 On the Thermodynamics of Biological Cell Adhesion

Authors: Ben Nadler

Abstract:

Cell adhesion plays a vital role in many cell activities. The motivation to model cell adhesion is to study important biological processes, such as cell spreading, cell aggregation, tissue formation, and cell adhesion, which are very challenging to study by experimental methods alone. This study provides important insight into cell adhesion, which can lead to improve regenerative medicine and tissue formation techniques. In this presentation the biological cells adhesion is mediated by receptors–ligands binding and the diffusivity of the receptor on the cell membrane surface. The ability of receptors to diffuse on the cell membrane surface yields a very unique and complicated adhesion mechanism, which is exclusive to cells. The phospholipid bilayer, which is the main component in the cell membrane, shows fluid-like behavior associated with the molecules’ diffusivity. The biological cell is modeled as a fluid-like membrane with negligible bending stiffness enclosing the cytoplasm fluid. The in-plane mechanical behavior of the cell membrane is assumed to depend only on the area change, which is motivated by the fluidity of the phospholipid bilayer. In addition, the presence of receptors influences on the local mechanical properties of the cell membrane is accounted for by including stress-free area change, which depends on the receptor density. Based on the physical properties of the receptors and ligands the attraction between the receptors and ligands is modeled as a charged-nonpolar which is a noncovalent interaction. Such interaction is a short-range type, which decays fast with distance. The mobility of the receptor on the cell membrane is modeled using the diffusion equation and Fick’s law is used to model the receptor–receptor interactions. The resultant interaction force, which includes receptor–ligand and receptor–receptor interaction, is decomposed into tangential part, which governs the receptor diffusion, and normal part, which governs the cell deformation and adhesion. The formulation of the governing equations and numerical simulations will be presented. Analysis of the adhesion characteristic and properties are discussed. The roles of various thermomechanical properties of the cell, receptors and ligands on the cell adhesion are investigated.

Keywords: cell adhesion, cell membrane, receptor-ligand interaction, receptor diffusion

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4733 Quantitative Analysis of Orphan Nuclear Receptors in Insulin Resistant C2C12 Skeletal Muscle Cells

Authors: Masocorro Gawned, Stephen Myers, Guat Siew Chew

Abstract:

Nuclear Receptors (NR) are a super family of transcription factors that play a major role in lipid and glucose metabolism in skeletal muscle. Recently, pharmacological evidence supports the view that stimulation of nuclear receptors alleviates Type 2 Diabetes (T2D). The orphan nuclear receptors (ONR) are members of the nuclear receptor (NR) superfamily whose ligands and physiological functions remain unknown. To date, no systematic studies have been carried out to screen for ONRs expressed in insulin resistant (IR) skeletal muscle cells. Therefore, in this study, we have established a model for IR by treating C2C12 skeletal muscle cells with insulin (10nM) for 48 hours. Western Blot analysis of phosphorylated AKT confirmed IR. Real-time quantitative polymerase chain reaction (qPCR) results highlighted key ONRs including NUR77 (NR4A1), NURR1 (NR4A2) and NOR1 (NR4A3) which have been associated with fatty acid oxidation regulation and glucose homeostasis. Increased mRNA expression levels of estrogen-related receptors (ERRs), REV-ERBα, NUR77, NURR1, NOR1, in insulin resistant C2C12 skeletal muscle cells, indicated that these ONRs could potentially play a pivotal regulatory role of insulin secretion in lipid metabolism. Taken together, this study has successfully contributed to the complete analysis of ONR in IR, and has filled in an important void in the study and treatment of T2D.

Keywords: type 2 diabetes, orphan nuclear receptors, transcription receptors, quantitative mRNA expression

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4732 Some Metal Levels in Muscle Tissue of Seven Fish Species from the Suğla and Beyşehir Lakes, Turkey

Authors: Haluk Özparlak, Murad Aydın Şanda, Gülşin Arslan

Abstract:

Phoxinellus anatolicus, Carassius gibelio, Sander lucioperca, Vimba vimba tenella, Capoeta capoeta, Tinca tinca from Suğla Lake (Turkey) and Phoxinellus anatolicus, Scardinius erythrophthalmus, Tinca tinca from Beyşehir Lake (Turkey) are economically important fish species and these fish have been consumed as food by local people. P. anatolicus is also endangered and endemic species from Turkey. In this study, concentrations of Cd, Co, Cr, Fe, Mn, Ni, Pb and Zn were determined in muscle tissue of these fish by using atomic absorption spectrophotometer. Levels of metals in the muscle tissue of all the fish specimens were compared with results of previous studies, the tolerance levels of national and international guidelines and the levels of Provisional Tolerable Weekly Intake (PTWI) limits set by FAO/WHO. Concentrations of Cd, Cr, Ni and Pb in the muscle tissue of all the fish specimens from Suğla and Beyşehir Lakes exceeded the tolerance levels of national and international guidelines. However, concentrations of Cd, Fe, Pb and Zn were below PTWI limits. Therefore, in terms of these metal levels, consumption of fresh filet of examined seven fish species (weekly up to about 300 g/person) doesn’t seem to be objectionable for human health.

Keywords: Beyşehir Lake, fish, metal levels, Suğla Lake

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4731 Assessment of Barriers to the Clinical Adoption of Cell-Based Therapeutics

Authors: David Pettitt, Benjamin Davies, Georg Holländer, David Brindley

Abstract:

Cellular based therapies, whose origins can be traced from the intertwined concepts of tissue engineering and regenerative medicine, have the potential to transform the current medical landscape and offer an approach to managing what were once considered untreatable diseases. However, despite a large increase in basic science activity in the cell therapy arena alongside a growing portfolio of cell therapy trials, the number of industry products available for widespread clinical use correlates poorly with such a magnitude of activity, with the number of cell-based therapeutics in mainstream use remaining comparatively low. This research serves to quantitatively assess the barriers to the clinical adoption of cell-based therapeutics through identification of unique barriers, specific challenges and opportunities facing the development and adoption of such therapies.

Keywords: cell therapy, clinical adoption, commercialization, translation

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4730 The Effect of Seated Distance on Muscle Activation and Joint Kinematics during Seated Strengthening in Patients with Stroke with Extensor Synergy Pattern in the Lower Limbs

Authors: Y. H. Chen, P. Y. Chiang, T. Sugiarto, I. Karsuna, Y. J. Lin, C. C. Chang, W. C. Hsu

Abstract:

Task-specific training with intense practice of functional tasks has been emphasized for the approaches in motor rehabilitation in patients with hemiplegic strokes. Although reciprocal actions which may increase demands on motor control during seated stepping exercise, motor control is not explicitly trained with emphasis and instruction focused on traditional strengthening. Apart from cycling and treadmill, various forms of seated exerciser are becoming available for the lower extremity exercise. The benefit of seated exerciser has been focused on the effect on the cardiopulmonary system. Thus, the aim of current study is to investigate the effect of seated distance on muscle activation during seated strengthening in patients with stroke with extensor synergy pattern in the lower extremities. Electrodes were placed on the surface of lower limbs muscles, including rectus femoris (RF), vastus lateralis (VL), biceps femoris (BF) and gastrocnemius (GT) of both sides. Maximal voluntary contraction (MVC) of the muscles were obtained to normalize the EMG amplitude obtained during dynamic trials with analog raw data digitized with a sampling frequency of 2000 Hz, fully rectified and the linear enveloped. Movement cycle was separated into two phases by pushing (PP) and Return (RP). Integral EMG (iEMG) is then used to quantify level of activation during each of the phases. Subjects performed strengthening with moderate resistance with speed of 60 rpm in two different distances (D1, short) and (D2, long). The results showed greater iEMG in RF and smaller iEMG in VL and BF with obvious increase range of motion of hip flexion in D1 condition. On the contrary, no significant involvement of RF while greater level of muscular activation in VL and BF during RP was found during PP in D2 condition. In addition, greater hip internal rotation was observed in D2 condition. In patients with stroke with abnormal tone revealed by extensor synergy in the lower extremities, shorter seated distance is suggested to facilitate hip flexor muscle activation while avoid inducing hyper extensor tone which may prevent a smooth repetitive motion. Repetitive muscular contraction exercise of hip flexor may be helpful for further gait training as it may assist hip flexion during swing phase of the walking.

Keywords: seated strengthening, patients with stroke, electromyography, synergy pattern

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4729 Effect of Pomegranate (Punica granatum) Seed Oil on Keratinocytes in Patients with Atopic Dermatitis

Authors: Fardis Teifoori, Mehdi Dehghani, Idoia Postigo, Jorge Martinez

Abstract:

Introduction: Many skin disorders, such as atopic dermatitis (AD), is characterized by inflammation, infection, and hyperplasia. In this work, keratinocytes from AD patients are used to study the pomegranate seed oil properties for skin care. Material and methods: Isolated keratinocytes from patients with AD were cultured and stimulated by IL-9 (20 ng/ml) and TNF-α (50ng/ml) for 48h to induce vascular endothelial growth factor (VEGF) and Regulated upon activation, normal T cell expressed and secreted (RANTES) production, respectively, in the presence of different concentrations of pomegranate seed oil (20, 50, 100, and 200 µM). Finally, the concentrations of RANTES and VEGF in the cell culture supernatant were quantified according to the standard protocol of commercial ELISA kits. Results: The results indicated that pomegranate seed oil concentrations of 50, 100, and 200 µM could significantly inhibit the production of VEGF and RANTES by stimulating keratinocytes with IL-9 (20 ng/ml) and TNF-α (50ng/ml), respectively. The decrease in VEGF and RANTES concentration in the presence of the pomegranate seed oil concentrations of 20 and 50 uM was not significant. Conclusion: It was concluded that pomegranate seed oil (PSO) counteracts atopic dermatitis conditions dose-dependently: with the highest effect at the concentration of 200 µM. We suggest that the inexpensive and easily available pomegranate seed oil is a good candidate for cosmetics and clinical utilization for skin care.

Keywords: atopic dermatitis, pomegranate, Punica granatum, RANTES, VEGF

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4728 Predictive Output Feedback Linearization for Safe Control of Collaborative Robots

Authors: Aliasghar Arab

Abstract:

Autonomous robots interacting with humans, as safety-critical nonlinear control systems, are complex closed-loop cyber-physical dynamical machines. Keeping these intelligent yet complicated systems safe and smooth during their operations is challenging. The aim of the safe predictive output feedback linearization control synthesis is to design a novel controller for smooth trajectory following while unsafe situations must be avoided. The controller design should obtain a linearized output for smoothness and invariance to a safety subset. Inspired by finite-horizon nonlinear model predictive control, the problem is formulated as constrained nonlinear dynamic programming. The safety constraints can be defined as control barrier functions. Avoiding unsafe maneuvers and performing smooth motions increases the predictability of the robot’s movement for humans when robots and people are working together. Our results demonstrate the proposed output linearization method obeys the safety constraints and, compared to existing safety-guaranteed methods, is smoother and performs better.

Keywords: robotics, collaborative robots, safety, autonomous robots

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4727 Study of the Effect of the Continuous Electric Field on the Rd Cancer Cell Line by Response Surface Methodology

Authors: Radia Chemlal, Salim Mehenni, Dahbia Leila Anes-boulahbal, Mohamed Kherat, Nabil Mameri

Abstract:

The application of the electric field is considered to be a very promising method in cancer therapy. Indeed, cancer cells are very sensitive to the electric field, although the cellular response is not entirely clear. The tests carried out consisted in subjecting the RD cell line under the effect of the continuous electric field while varying certain parameters (voltage, exposure time, and cell concentration). The response surface methodology (RSM) was used to assess the effect of the chosen parameters, as well as the existence of interactions between them. The results obtained showed that the voltage, the cell concentration as well as the interaction between voltage and exposure time have an influence on the mortality rate of the RD cell line.

Keywords: continuous electric field, RD cancer cell line, RSM, voltage

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4726 Developing Wearable EMG Sensor Designed for Parkinson's Disease (PD) Monitoring, and Treatment

Authors: Bulcha Belay Etana

Abstract:

Electromyography is used to measure the electrical activity of muscles for various health monitoring applications using surface electrodes or needle electrodes. Recent developments in electromyogram signal acquisition using textile electrodes open the door for wearable health monitoring which enables patients to monitor and control their health issues outside of traditional healthcare facilities. The aim of this research is therefore to develop and analyze wearable textile electrodes for the acquisition of electromyography signals for Parkinson’s patients and apply an appropriate thermal stimulus to relieve muscle cramping. In order to achieve this, textile electrodes are sewn with a silver-coated thread in an overlapping zigzag pattern into an inextensible fabric, and stainless steel knitted textile electrodes attached to a sleeve were prepared and its electrical characteristics including signal to noise ratio were compared with traditional electrodes. To relieve muscle cramping, a heating element using stainless steel conductive yarn Sewn onto a cotton fabric, coupled with a vibration system were developed. The system was integrated using a microcontroller and a Myoware muscle sensor so that when muscle cramping occurs, measured by the system activates the heating elements and vibration motors. The optimum temperature considered for treatment was 35.50c, so a Temperature measurement system was incorporated to deactivate the heating system when the temperature reaches this threshold, and the signals indicating muscle cramping have subsided. The textile electrode exhibited a signal to noise ratio of 6.38dB while the signal to noise ratio of the traditional electrode was 7.05dB. The rise time of the developed heating element was about 6 minutes to reach the optimum temperature using a 9volt power supply. The treatment of muscle cramping in Parkinson's patients using heat and muscle vibration simultaneously with a wearable electromyography signal acquisition system will improve patients’ livelihoods and enable better chronic pain management.

Keywords: electromyography, heating textile, vibration therapy, parkinson’s disease, wearable electronic textile

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4725 Wireless Backhauling for 5G Small Cell Networks

Authors: Abdullah A. Al Orainy

Abstract:

Small cell backhaul solutions need to be cost-effective, scalable, and easy to install. This paper presents an overview of small cell backhaul technologies. Wireless solutions including TV white space, satellite, sub-6 GHz radio wave, microwave and mmWave with their backhaul characteristics are discussed. Recent research on issues like beamforming, backhaul architecture, precoding and large antenna arrays, and energy efficiency for dense small cell backhaul with mmWave communications is reviewed. Recent trials of 5G technologies are summarized.

Keywords: backhaul, small cells, wireless, 5G

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4724 A Comparative Study of Active Release Technique and Myofascial Release Technique in Treatment of Patients with Upper Trapezius Spasm

Authors: Daxa Mishra, R. Harihara, Ankita

Abstract:

Trapezius muscle pain is the most common musculoskeletal disorder occurring in individuals who work with awkward positions, have repetitive movements and movements with precision demands. Treatment techniques like active release technique (ART) and myofascial release (MFR) can be used to relieve muscle spasm. The aim of the study is to compare the effect of ART and MFR on the upper trapezius muscle spasm. Methodology: A series of 60 patients of both sexes between the age group of 20 and 55 with upper trapezius spasm were divided into two groups by computerized randomization. Subjects in each group received treatment in the form of either ART or MFR for the period of seven days. cervical range of motion (ROM), neck disability index scale (NDI) and visual analog scale (VAS) tools were used to measure the outcome. Results: Paired Sample ‘t’ test was used to compare the Outcome differences within each group, while Independent ‘t’ test was used to compare the differences between the two groups for the same outcome measures. The improvement was found in both the groups at 7th day following intervention, but the group which received ART showed significant improvements as compared to group which received MFR. Conclusion: Although both techniques are effective in alleviation of symptoms and associated disability in upper trapezius muscle spasm, ART gave better results as compared to MRF.

Keywords: goniometer, myofascial release, active release, physiotherapy

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4723 Modeling and Simulation of Organic Solar Cells Based on P3HT:PCBM using SCAPS 1-D (Influence of Defects and Temperature on the Performance of the Solar Cell)

Authors: Souhila Boukli Hacene, Djamila Kherbouche, Abdelhak Chikhaoui

Abstract:

In this work, we elucidate theoretically the effect of defects and temperature on the performance of the organic bulk heterojunction solar cell (BHJ) P3HT: PCBM. We have studied the influence of their parameters on cell characteristics. For this purpose, we used the effective medium model and the solar cell simulator (SCAPS) to model the characteristics of the solar cell. We also explore the transport of charge carriers in the device. It was assumed that the mixture is lightly p-type doped and that the band gap contains acceptor defects near the HOMO level with a Gaussian distribution of energy states at 100 and 50 meV. We varied defects density between 1012-1017 cm-3, from 1016 cm-3, a total decrease of the photovoltaic characteristics due to the increase of the non-radiative recombination can be noticed. Then we studied the effect of variation of the electron and the hole capture cross-section on the cell’s performance, we noticed that the cell obtains a better efficiency of about 3.6% for an electron capture cross section ≤ 10-15 cm2 and a hole capture cross section ≤ 10-19 cm2. On the other hand, we also varied the temperature between 120K and 400K. We observed that the temperature of the solar cell induces a noticeable effect on its voltage. While the effect of temperature on the solar cell current is negligible.

Keywords: organic solar cell, P3HT:PCBM, defects, temperature, SCAPS

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4722 The Effects of an Exercise Program Integrated with the Transtheoretical Model on Pain and Trunk Muscle Endurance of Rice Farmers with Chronic Low Back Pain

Authors: Thanakorn Thanawat, Nomjit Nualnetr

Abstract:

Background and Purpose: In Thailand, rice farmers have the most prevalence of low back pain when compared with other manual workers. Exercises have been suggested to be a principal part of treatment programs for low back pain. However, the programs should be tailored to an individual’s readiness to change categorized by a behavioral approach. This study aimed to evaluate a difference between the responses of rice farmers with chronic low back pain who received an exercise program integrated with the transtheoretical model of behavior change (TTM) and those of the comparison group regarding severity of pain and trunk muscle endurance. Materials and Methods: An 8-week exercise program was conducted to rice farmers with chronic low back pain who were randomized to either the TTM (n=62, 52 woman and 10 men, mean age ± SD 45.0±5.4 years) or non-TTM (n=64, 53 woman and 11 men, mean age ± SD 44.7±5.4 years) groups. All participants were tested for their severity of pain and trunk (abdominal and back) muscle endurance at baseline (week 0) and immediately after termination of the program (week 8). Data were analysed by using descriptive statistics and student’s t-tests. The results revealed that both TTM and non-TTM groups could decrease their severity of pain and improve trunk muscle endurance after participating in the 8-week exercise program. When compared with the non-TTM group, however, the TTM showed a significantly greater increase in abdominal muscle endurance than did the non-TTM (P=0.004, 95% CI -12.4 to -2.3). Conclusions and Clinical Relevance: An exercise program integrated with the TTM could provide benefits to rice farmers with chronic low back pain. Future studies with a longitudinal design and more outcome measures such as physical performance and quality of life are suggested to reveal further benefits of the program.

Keywords: chronic low back pain, transtheoretical model, rice farmers, exercise program

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4721 Study on the Impact of Power Fluctuation, Hydrogen Utilization, and Fuel Cell Stack Orientation on the Performance Sensitivity of PEM Fuel Cell

Authors: Majid Ali, Xinfang Jin, Victor Eniola, Henning Hoene

Abstract:

The performance of proton exchange membrane (PEM) fuel cells is sensitive to several factors, including power fluctuations, hydrogen utilization, and the quality orientation of the fuel cell stack. In this study, we investigate the impact of these factors on the performance of a PEM fuel cell. We start by analyzing the power fluctuations that are typical in renewable energy systems and their effects on the 50 Watt fuel cell's performance. Next, we examine the hydrogen utilization rate (0-1000 mL/min) and its impact on the cell's efficiency and durability. Finally, we investigate the quality orientation (three different positions) of the fuel cell stack, which can significantly affect the cell's lifetime and overall performance. The basis of our analysis is the utilization of experimental results, which have been further validated by comparing them with simulations and manufacturer results. Our results indicate that power fluctuations can cause significant variations in the fuel cell's voltage and current, leading to a reduction in its performance. Moreover, we show that increasing the hydrogen utilization rate beyond a certain threshold can lead to a decrease in the fuel cell's efficiency. Finally, our analysis demonstrates that the orientation of the fuel cell stack can affect its performance and lifetime due to non-uniform distribution of reactants and products. In summary, our study highlights the importance of considering power fluctuations, hydrogen utilization, and quality orientation in designing and optimizing PEM fuel cell systems. The findings of this study can be useful for researchers and engineers working on the development of fuel cell systems for various applications, including transportation, stationary power generation, and portable devices.

Keywords: fuel cell, proton exchange membrane, renewable energy, power fluctuation, experimental

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4720 A Rare Case Report of Wandering Spleen Torsion

Authors: Steven Robinson, Adriana Dager, Param Patel

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Wandering spleen is a rare variant where there is abnormal development of the ligamentous peritoneal attachments of the spleen which normally anchor it in the left upper quadrant of the abdomen. Ligamentous abnormalities can be congenital, or acquired through pregnancy, injury, or iatrogenic causes. Absence or laxity of these ligaments allows migration of the spleen into ectopic portions of the abdomen, which is also associated with an elongated vascular pedicle. Incidence of wandering spleen is reported at less than 0.25% with a female to male ratio of approximately 6:1. The most common complication of a wandering spleen is torsion around its vascular pedicle which can lead to thrombosis and infarction. Torsion of a wandering spleen is a rare but important cause of an acute abdomen. Imaging, and specifically CT or ultrasound, is crucial in the diagnosis. We present a case of a torsed wandering spleen which was treated with splenectomy.

Keywords: Wandering Spleen, Torsion, Splenic Torsion, Spleen

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4719 A Novel Epitope Prediction for Vaccine Designing against Ebola Viral Envelope Proteins

Authors: Manju Kanu, Subrata Sinha, Surabhi Johari

Abstract:

Viral proteins of Ebola viruses belong to one of the best studied viruses; however no effective prevention against EBOV has been developed. Epitope-based vaccines provide a new strategy for prophylactic and therapeutic application of pathogen-specific immunity. A critical requirement of this strategy is the identification and selection of T-cell epitopes that act as vaccine targets. This study describes current methodologies for the selection process, with Ebola virus as a model system. Hence great challenge in the field of ebola virus research is to design universal vaccine. A combination of publicly available bioinformatics algorithms and computational tools are used to screen and select antigen sequences as potential T-cell epitopes of supertypes Human Leukocyte Antigen (HLA) alleles. MUSCLE and MOTIF tools were used to find out most conserved peptide sequences of viral proteins. Immunoinformatics tools were used for prediction of immunogenic peptides of viral proteins in zaire strains of Ebola virus. Putative epitopes for viral proteins (VP) were predicted from conserved peptide sequences of VP. Three tools NetCTL 1.2, BIMAS and Syfpeithi were used to predict the Class I putative epitopes while three tools, ProPred, IEDB-SMM-align and NetMHCII 2.2 were used to predict the Class II putative epitopes. B cell epitopes were predicted by BCPREDS 1.0. Immunogenic peptides were identified and selected manually by putative epitopes predicted from online tools individually for both MHC classes. Finally sequences of predicted peptides for both MHC classes were looked for common region which was selected as common immunogenic peptide. The immunogenic peptides were found for viral proteins of Ebola virus: epitopes FLESGAVKY, SSLAKHGEY. These predicted peptides could be promising candidates to be used as target for vaccine design.

Keywords: epitope, b cell, immunogenicity, ebola

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4718 Passive Heat Exchanger for Proton Exchange Membrane Fuel Cell Cooling

Authors: Ivan Tolj

Abstract:

Water produced during electrochemical reaction in Proton Exchange Membrane (PEM) fuel cell can be used for internal humidification of reactant gases; hydrogen and air. On such a way it is possible to eliminate expensive external humidifiers and simplify fuel cell balance-of-plant (BoP). When fuel cell operates at constant temperature (usually between 60 °C and 80 °C) relatively cold and dry ambient air heats up quickly upon entering channels which cause further drop in relative humidity (below 20%). Low relative humidity of reactant gases dries up polymer membrane and decrease its proton conductivity which results in fuel cell performance drop. It is possible to maintain such temperature profile throughout fuel cell cathode channel which will result in close to 100 % RH. In order to achieve this, passive heat exchanger was designed using commercial CFD software (ANSYS Fluent). Such passive heat exchanger (with variable surface area) is suitable for small scale PEM fuel cells. In this study, passive heat exchanger for single PEM fuel cell segment (with 20 x 1 cm active area) was developed. Results show close to 100 % RH of air throughout cathode channel with increased fuel cell performance (mainly improved polarization curve) and improved durability.

Keywords: PEM fuel cell, passive heat exchange, relative humidity, thermal management

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4717 Targeting Matrix Metalloprotease-9 to Reduce Coronary Artery Manifestations of Kawasaki’s Disease

Authors: Mohammadjavad Sotoudeheian, Navid Farahmandian

Abstract:

Kawasaki disease (KD) is the primary cause of acquired pediatric heart disease as an acute vasculitis. In children with prolonged fever, rash, and inflammation of the mucosa KD must be considered as a clinical diagnosis. There is a persuasive suggestion of immune-mediated damage as the pathophysiologic cascade of KD. For example, the invasion of cytotoxic T-cells supports a viral etiology and the inflammasome of the innate immune system is a critical component in the vasculitis formation in KD. Animal models of KD propose the cytokine profiles, such as increased IL-1 and GM-CSF, which cause vascular damage. CRP and IFN-γ elevated expression and the upregulation of IL-6, and IL-10 production are also described in previous studies. Untreated KD is a critical risk factor for coronary artery diseases and myocardial infarction. Vascular damage may encompass amplified T-cell activity. SMAD3 is an essential molecule in down-regulating T-cells and increasing expression of FoxP3. It has a critical effect in the differentiation of regulatory T-cells. The discrepancy of regulatory T-cells and pro-inflammatory Th17 has been studied in acute coronary syndrome during KD. However in the coronary artery damaged lymphocytes and IgA plasma cells are seen at the lesion locations, the major immune cells in the coronary lesions are monocytes/macrophages and neutrophils. These cells secrete TNF-α, and activates matrix metalloprotease (MMP)-9, reducing the integrity of vessels and prompting patients to arise aneurysm. MMPs can break down the components of the extracellular matrix and assist immune cell movement. IVIG as an effective form of treatment clarified the role of the immune system, which may target pathogenic antigens and regulate cytokine production. Several reports have revealed that in the coronary arteries, high expression of MMP-9 in monocyte/macrophage results in pathologic cascades. Curcumin is a potent antioxidant and anti-inflammatory molecule. Curcumin decreases the production of reactive oxygen and nitrogen species and inhibits transcription factors like AP-1 and NF-κB. Curcumin also contains the characteristics of inhibitory effects on MMPs, especially MMP-9. The upregulation of MMP-9 is an important cellular response. Curcumin treatment caused a reverse effect and down-regulates MMP-9 gene expression which may fund the anti-inflammatory effect. Curcumin inhibits MMP-9 expression via PKC and AMPK-dependent pathways in Human monocytes cells. Elevated expression and activity of MMP-9 are correlated with advanced vascular lesions. AMPK controls lipid metabolism and oxidation, and protein synthesis. AMPK is also necessary for the MMP-9 activity and THP-1 cell adhesion to endothelial cells. Curcumin was shown to inhibit the activation of AMPKα. Compound C (AMPK inhibitor) inhibits MMP-9 expression level. Therefore, through inactivating AMPKs and PKC, curcumin decreases the MMP-9 level, which results in inhibiting monocyte/macrophage differentiation. Compound C also suppress the phosphorylation of three major classes of MAP kinase signaling, suggesting that curcumin may suppress MMP-9 level by inactivation of MAPK pathways. MAPK cascades are activated to induce the expression of MMP-9. Curcumin inhibits MAPKs phosphorylation, which contributes to the down-regulation of MMP-9. This study demonstrated that the potential inhibitory properties of curcumin over MMP-9 lead to a therapeutic strategy to reduce the risk of coronary artery involvement during KD.

Keywords: MMP-9, coronary artery aneurysm, Kawasaki’s disease, curcumin, AMPK, immune system, NF-κB, MAPK

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4716 Resistive Switching in TaN/AlNx/TiN Cell

Authors: Hsin-Ping Huang, Shyankay Jou

Abstract:

Resistive switching of aluminum nitride (AlNx) thin film was demonstrated in a TaN/AlNx/TiN memory cell that was prepared by sputter deposition techniques. The memory cell showed bipolar switching of resistance between +3.5 V and –3.5 V. The resistance ratio of high resistance state (HRS) to low resistance state (HRS), RHRS/RLRS, was about 2 over 100 cycles of endurance test. Both the LRS and HRS of the memory cell exhibited ohmic conduction at low voltages and Poole-Frenkel emission at high voltages. The electrical conduction in the TaN/AlNx/TiN memory cell was possibly attributed to the interactions between charges and defects in the AlNx film.

Keywords: aluminum nitride, nonvolatile memory, resistive switching, thin films

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4715 The Effect of Physical Therapy on Triceps Surae Myofascial Trigger Point

Authors: M. Simon, O. Peillon, R. Seijas, P. Alvarez, A. Pérez-Bellmunt

Abstract:

Introduction: Myofascial trigger points (MTrPs) are defined as hyperirritable areas within taut bands of skeletal muscle and classified as either active or latent. Although they could be present in any muscle, the triceps surae is one of the most affected of the lower limb. The aim of this study was described which treatments are more used and their principal results. Study design: We performed a systematic literature search using strategies for the concepts of “Trigger Points and Gastrocnemius and Soleus not Trapezius” in Medline. Articles were screened by authors and included if they contained a rehabilitation intervention of MTrPs in healthy subjects or patients. Results: The treatments used were mostly invasive interventions and only a small part of the studies used non-invasive treatments. The methodology (time o type of intervention, characteristics of treatment, etc.) used in these treatments were frequently undefined. Overall, examination variables varied significantly among the included studies, but they were improving their parameters when the MTrPs were treated. Conclusions: There are a high variety of physical therapy treatments to improve the symptomatology of MTrPs when affect triceps surae muscle. Even so, not a single study analyzing the skeletal muscle contractile parameters (as maximal displacement or delay time) change with MTrPS therapy has been found. The treatments have to better specificity the methodology used in the futures investigation.

Keywords: fascia, myofascial trigger points, physical therapy, triceps surae

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4714 The Differences of Vascular Endothelial Growth Factor Levels in Serum to Determine Follicular Adenoma and Follicular Carcinoma of Thyroid

Authors: Tery Nehemia Nugraha Joseph, J. D. P. Wisnubroto

Abstract:

Thyroid cancer is a healthcare problem with high morbidity and mortality. Follicular adenoma and follicular carcinoma are thyroid tumors from the thyroid follicular cells differentiation with a microfollicular pattern that consists of follicular cuboidal cells. vascular endothelial growth factor (VEGF) is a potent and powerful mitogen for endothelial cells and increases vascular permeability. Therefore, due to an increase in thyroid-stimulating hormone (TSH), VEGF production is activated in the thyroid that leads to the end of mitogenic TSH stimulation and initiation of angiogenesis. The differences in VEGF levels in the follicular carcinoma of thyroid tissue with follicular adenoma thyroid can be used as a basis in differentiating the two types of neoplasms. This study aims to analyze VEGF in the serum so that it can be used to differentiate the types of thyroid carcinoma before surgery. This study uses a cross-sectional research design. Samples were carried out by taking serum samples, and the VEGF levels were calculated. Data were analyzed using the Mann-Whitney test. The results found a significant difference between VEGF levels in the follicular carcinoma thyroid group and VEGF levels in the follicular adenoma thyroid group with a value of p = 0.007 (p < 0.05). The results obtained are 560,427 ± 160,506 ng/mL in the type of follicular carcinoma thyroid and 320.943 ± 134.573 ng/mL in the type of follicular adenoma thyroid. VEGF levels between follicular adenoma and follicular carcinoma are different. VEGF levels are higher in follicular carcinoma thyroid than follicular adenoma thyroid.

Keywords: follicular adenoma thyroid, follicular carcinoma thyroid, thyroid, VEGF

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4713 Theoretical Analysis of Graded Interface CdS/CIGS Solar Cell

Authors: Hassane Ben Slimane, Dennai Benmoussa, Abderrachid Helmaoui

Abstract:

We have theoretically calculated the photovoltaic conversion efficiency of a graded interface CdS/CIGS solar cell, which can be experimentally fabricated. Because the conduction band discontinuity or spike in an abrupt heterojunction CdS/CIGS solar cell can hinder the separation of hole-electron by electric field, a graded interface layer is uses to eliminate the spike and reduces recombination in space charge region. This paper describes the role of the graded band gap interface layer in decreasing the performance of the heterojunction cell. By optimizing the thickness of the graded region, an improvement of conversion efficiency has been observed in comparison to the conventional CIGS system.

Keywords: heterojunction, solar cell, graded interface, CIGS

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4712 Influence of HbA1c on Nitric Oxide Level in Patients with Type 2 Diabetes Mellitus

Authors: Dara Kutsyk, Olga Bondarenko, Mariya Sorochka

Abstract:

In 21-century type 2 diabetes (T2D) has become a global health and social problem in the whole world. The goal of treatment for patients with T2D is to prevent complications of diabetes - macrovascular diseases (heart disease, stroke, and peripheral vascular disease) and microvascular diseases (retinopathy, neuropathy and nephropathy). Nitric oxide (NO) plays an important role in maintaining vascular homeostasis. Loss of NO function is one of the earliest indicators of disease and its progression especially in patients with T2D. Aim: To compare NO level between patients with well and bad controlled glycemia in T2D. Methods: The study included 32 patients with T2D. The diagnosis of T2D was confirmed due to International Diabetes Federation (IDF) criteria 2015. Patients were divided into two groups: with well controlled glycaemia (HbA1c < 7%) and bad controlled glycaemia (HbA1c > 7%). The control group consists of 15 healthy subjects. Results: NO level in patients with T2D is significantly higher (27,2 ±3,1 µmol), compared to controls (18,86±0,9 µmol; p < 0,001). A significant difference in NO level was found between patients with bad controlled glycaemia (25,9±2,2 µmol) and well controlled glycaemia (28,7 ± 3,0 µmol; p<0,01). The study showed a moderate negative correlation between NO level and HbA1c (-0,399; р< 0,05). Conclusions: Production of NO is impaired in patients with T2D, especially with badly controlled glycaemia. With the increase in HbAc serum NO decreases. This can be the main target for prevention vascular complication in T2D.

Keywords: type 2 diabetes, glycated hemoglobin, nitric oxide, Diabetes mellitus

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4711 Relative Importance of Different Mitochondrial Components in Maintaining the Barrier Integrity of Retinal Endothelial Cells: Implications for Vascular-associated Retinal Diseases

Authors: Shaimaa Eltanani, Thangal Yumnamcha, Ahmed S. Ibrahim

Abstract:

Purpose: Mitochondria dysfunction is central to breaking the barrier integrity of retinal endothelial cells (RECs) in various blinding eye diseases such as diabetic retinopathy and retinopathy of prematurity. Therefore, we aimed to dissect the role of different mitochondrial components, specifically, those of oxidative phosphorylation (OxPhos), in maintaining the barrier function of RECs. Methods: Electric cell-substrate impedance sensing (ECIS) technology was used to assess in real-time the role of different mitochondrial components in the total impedance (Z) of human RECs (HRECs) and its components; the capacitance (C) and the total resistance (R). HRECs were treated with specific mitochondrial inhibitors that target different steps in OxPhos: Rotenone for complex I; Oligomycin for ATP synthase; and FCCP for uncoupling OxPhos. Furthermore, data were modeled to investigate the effects of these inhibitors on the three parameters that govern the total resistance of cells: cell-cell interactions (Rb), cell-matrix interactions (α), and cell membrane permeability (Cm). Results: Rotenone (1 µM) produced the greatest reduction in the Z, followed by FCCP (1 µM), whereas no reduction in the Z was observed after the treatment with Oligomycin (1 µM). Following this further, we deconvoluted the effect of these inhibitors on Rb, α, and Cm. Firstly, rotenone (1 µM) completely abolished the resistance contribution of Rb, as the Rb became zero immediately after the treatment. Secondly, FCCP (1 µM) eliminated the resistance contribution of Rb only after 2.5 hours and increased Cm without considerable effect on α. Lastly, Oligomycin had the lowest impact among these inhibitors on Rb, which became similar to the control group at the end of the experiment without noticeable effects on Cm or α. Conclusion: These results demonstrate differential roles for complex I, complex V, and coupling of OxPhos in maintaining the barrier functionality of HRECs, in which complex I being the most important component in regulating the barrier functionality and the spreading behavior of HRECs. Such differences can be used in investigating gene expression as well as for screening selective agents that improve the functionality of complex I to be used in the therapeutic approach for treating REC-related retinal diseases.

Keywords: human retinal endothelial cells (hrecs), rotenone, oligomycin, fccp, oxidative phosphorylation, oxphos, capacitance, impedance, ecis modeling, rb resistance, α resistance, and barrier integrity

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4710 A Case of Prosthetic Vascular-Graft Infection Due to Mycobacterium fortuitum

Authors: Takaaki Nemoto

Abstract:

Case presentation: A 69-year-old Japanese man presented with a low-grade fever and fatigue that had persisted for one month. The patient had an aortic dissection on the aortic arch 13 years prior, an abdominal aortic aneurysm seven years prior, and an aortic dissection on the distal aortic arch one year prior, which were all treated with artificial blood-vessel replacement surgery. Laboratory tests revealed an inflammatory response (CRP 7.61 mg/dl), high serum creatinine (Cr 1.4 mg/dL), and elevated transaminase (AST 47 IU/L, ALT 45 IU/L). The patient was admitted to our hospital on suspicion of prosthetic vascular graft infection. Following further workups on the inflammatory response, an enhanced chest computed tomography (CT) and a non-enhanced chest DWI (MRI) were performed. The patient was diagnosed with a pulmonary fistula and a prosthetic vascular graft infection on the distal aortic arch. After admission, the patient was administered Ceftriaxion and Vancomycine for 10 days, but his fever and inflammatory response did not improve. On day 13 of hospitalization, a lung fistula repair surgery and an omental filling operation were performed, and Meropenem and Vancomycine were administered. The fever and inflammatory response continued, and therefore we took repeated blood cultures. M. fortuitum was detected in a blood culture on day 16 of hospitalization. As a result, we changed the treatment regimen to Amikacin (400 mg/day), Meropenem (2 g/day), and Cefmetazole (4 g/day), and the fever and inflammatory response began to decrease gradually. We performed a test of sensitivity for Mycobacterium fortuitum, and found that the MIC was low for fluoroquinolone antibacterial agent. The clinical course was good, and the patient was discharged after a total of 8 weeks of intravenous drug administration. At discharge, we changed the treatment regimen to Levofloxacin (500 mg/day) and Clarithromycin (800 mg/day), and prescribed these two drugs as a long life suppressive therapy. Discussion: There are few cases of prosthetic vascular graft infection caused by mycobacteria, and a standard therapy remains to be established. For prosthetic vascular graft infections, it is ideal to provide surgical and medical treatment in parallel, but in this case, surgical treatment was difficult and, therefore, a conservative treatment was chosen. We attempted to increase the treatment success rate of this refractory disease by conducting a susceptibility test for mycobacteria and treating with different combinations of antimicrobial agents, which was ultimately effective. With our treatment approach, a good clinical course was obtained and continues at the present stage. Conclusion: Although prosthetic vascular graft infection resulting from mycobacteria is a refractory infectious disease, it may be curative to administer appropriate antibiotics based on the susceptibility test in addition to surgical treatment.

Keywords: prosthetic vascular graft infection, lung fistula, Mycobacterium fortuitum, conservative treatment

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4709 Effects of Branched-Chain Amino Acid Supplementation on Sarcopenic Patients with Liver Cirrhosis

Authors: Deepak Nathiya1, Ramesh Roop Rai, Pratima Singh1, Preeti Raj1, Supriya Suman, Balvir Singh Tomar

Abstract:

Background: Sarcopenia is a catabolic state in liver cirrhosis (LC), accelerated with a breakdown of skeletal muscle to release amino acids which adversely affects survival, health-related quality of life, and response to any underlying disease. The primary objective of the study was to investigate the long-term effect of branched-chain amino acids (BCAA) supplementations on parameters associated with improved prognosis in sarcopenic patients with LC, as well as to evaluate its impact on cirrhotic-related events. Methods: We carried out a 24 week, single-center, randomized, open-label, controlled, two cohort parallel-group intervention trial comparing the efficacy of BCAA against lactoalbumin (L-ALB) on 106 sarcopenic liver cirrhotics. The BCAA (intervention) group was treated with 7.2 g BCAA per whereas, the lactoalbumin group was also given 6.3 g of L-Albumin. The primary outcome was to assess the impact of BCAA on parameters of sarcopenia: muscle mass, muscle strength, and physical performance. The secondary outcomes were to study combined survival and maintenance of liver function changes in laboratory and clinical markers in the duration of six months. Results: Treatment with BCAA leads to significant improvement in sarcopenic parameters: muscle strength, muscle function, and muscle mass. The total cirrhotic-related complications and cumulative event-free survival occurred fewer in the BCAA group than in the L-ALB group. Prognostic markers also improved significantly in the study. Conclusion: The current clinical trial demonstrated that long-term BCAAs supplementation improved sarcopenia and prognostic markers in patients with advanced liver cirrhosis.

Keywords: sarcopenia, liver cirrhosis, BCAA, quality of life

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4708 Puereria mirifica Replacement Improves Skeletal Muscle Performance Associated with Increasing Parvalbumin Levels in Ovariectomized Rat

Authors: Uraporn Vongvatcharanon, Kochakorn Sukjan, Wandee Udomuksorn, Ekkasit Kumarnsit, Surapong Vongvatcharanon

Abstract:

Sarcopenia is a loss of muscle mass, and strength frequently found in menopause. Estrogen replacement has been shown to improve such a loss of muscle functions. However, there is an increased risk of cancer that has to be considered because of the estrogen replacement therapy. Thus, phytoestrogen supplementation has been suggested as an alternative therapy. Pueraria mirifica (PM) is a plant in the family Leguminosae, that is known to be phytoestrogen-rich and has been traditionally used for the treatment of menopausal symptoms. It contains isoflavones and other compounds such as miroestrol and its derivatives. Parvalbumin (PV) is a calcium binding protein and functions as a relaxing factor in fast twitch muscle fibers. A decrease of the PV level results in a reduction of the speed of the twitch relaxation. Therefore, this study aimed to investigate the effect of an ethanolic extract from Pueraria mirifica on the estrogen levels, skeletal muscle functions and PV levels in the extensor digitorum longus (EDL) and gastrocnemius of ovariectomized rats. Twelve-week old female Wistar rats (200-250 g) were divided into 6 groups: SHAM (un-ovariectomized rats, that received double distilled water), PM-0 (ovariectomized rats, OVX, receiving double distilled water), E (OVX, receiving an estradiol benzoate dose of 0.04 mg/kg), PM-50 (OVX receiving PM 50 mg/kg), PM-500 (OVX receiving PM 500 mg/kg), PM-1000 (OVX receiving PM 1000 mg/kg) all for 90 days. The PM-0 group had estrogen levels, uterus weights, muscle mass, myofiber cross-section areas, peak tension, fatigue resistance, speed of relaxation and parvalbumin levels of both EDL and gastrocnemius that were significantly reduced compared to those of the SHAM group (p<0.05). Also the α and β estrogen receptor immunoreactivities and the parvalbumin immunoreactivities of both EDL and gastrocnemius were decreased in the PM-0 group. In contrast the E, PM-50, PM-500 and PM-1000 group had estrogen levels, uterus weights, muscle mass, myofiber cross-section areas, peak tension, fatigue resistance, speed of relaxation of both EDL and gastrocnemius that were significantly increased compared with PM-0 group (p<0.05). In addition, the α and β estrogen receptor immunoreactivities and parvalbumin immunoreactivity of both the EDL and gastrocnemius were increased in the E, PM-50, PM-500 and PM-1000 group. In addition the extract of Pueraria mirifica replacement group at 50 and 500 mg/kg had significantly increased parvalbumin levels in the EDL muscle but in the gastrocnemius, only the dose of 500 mg/kg increased the parvalbumin levels (p<0.05). These results have demonstrated that the use of the Pueraria mirifica extract as a replacement therapy for estrogen produced estrogenic activity that was similar to that produced by the estradiol benzoate replacement. It seems that the phytoestrogens could bind with the estrogen receptors and stimulate the transcriptional activity to synthesise muscle protein that caused an increase in muscle mass and parvalbumin levels. Thus, muscle synthesis may restore parvalbumin levels resulting in an enhanced relaxation efficiency that would lead to a shortened latent period before the next contraction.

Keywords: Puereria mirifica, Parvalbumin, estrogen, ovariectomized rats

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4707 Numerical Reproduction of Hemodynamic Change Induced by Acupuncture to ST-36

Authors: Takuya Suzuki, Atsushi Shirai, Takashi Seki

Abstract:

Acupuncture therapy is one of the treatments in traditional Chinese medicine. Recently, some reports have shown the effectiveness of acupuncture. However, its full acceptance has been hindered by the lack of understanding on mechanism of the therapy. Acupuncture applied to Zusanli (ST-36) enhances blood flow volume in superior mesenteric artery (SMA), yielding peripheral vascular resistance – regulated blood flow of SMA dominated by the parasympathetic system and inhibition of sympathetic system. In this study, a lumped-parameter approximation model of blood flow in the systemic arteries was developed. This model was extremely simple, consisting of the aorta, carotid arteries, arteries of the four limbs and SMA, and their peripheral vascular resistances. Here, the individual artery was simplified to a tapered tube and the resistances were modelled by a linear resistance. We numerically investigated contribution of the peripheral vascular resistance of SMA to the systemic blood distribution using this model. In addition to the upstream end of the model, which correlates with the left ventricle, two types of boundary condition were applied; mean left ventricular pressure which correlates with blood pressure (BP) and mean cardiac output which corresponds to cardiac index (CI). We examined it to reproduce the experimentally obtained hemodynamic change, in terms of the ratio of the aforementioned hemodynamic parameters from their initial values before the acupuncture, by regulating the peripheral vascular resistances and the upstream boundary condition. First, only the peripheral vascular resistance of SMA was changed to show contribution of the resistance to the change in blood flow volume in SMA, expecting reproduction of the experimentally obtained change. It was found, however, this was not enough to reproduce the experimental result. Then, we also changed the resistances of the other arteries together with the value given at upstream boundary. Here, the resistances of the other arteries were changed simultaneously in the same amount. Consequently, we successfully reproduced the hemodynamic change to find that regulation of the upstream boundary condition to the value experimentally obtained after the stimulation is necessary for the reproduction, though statistically significant changes in BP and CI were not observed in the experiment. It is generally known that sympathetic and parasympathetic tones take part in regulation of whole the systemic circulation including the cardiac function. The present result indicates that stimulation to ST-36 could induce vasodilation of peripheral circulation of SMA and vasoconstriction of that of other arteries. In addition, it implies that experimentally obtained small changes in BP and CI induced by the acupuncture may be involved in the therapeutic response.

Keywords: acupuncture, hemodynamics, lumped-parameter approximation, modeling, systemic vascular resistance

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