scholarly journals Development of Cell-Carrying Magnetic Microrobots with Bioactive Nanostructured Titanate Surface for Enhanced Cell Adhesion

Micromachines ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1572
Author(s):  
Junyang Li ◽  
Lei Fan ◽  
Yanfang Li ◽  
Tanyong Wei ◽  
Cheng Wang ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cell Adhesion ◽  
The Body ◽  
Cell Delivery ◽  
Magnetic Actuation ◽  
Activity Assay ◽  
Laser Lithography ◽  
Naoh Solution ◽  
Magnetic Microrobots ◽  
Opening Up

Cell-carrying magnet-driven microrobots are easily affected by blood flow or body fluids during transportation in the body, and thus cells often fall off from the microrobots. To reduce the loss of loaded cells, we developed a microrobot with a bioactive nanostructured titanate surface (NTS), which enhances cell adhesion. The microrobot was fabricated using 3D laser lithography and coated with nickel for magnetic actuation. Then, the microrobot was coated with titanium for the external generation of an NTS through reactions in NaOH solution. Enhanced cell adhesion may be attributed to the changes in the surface wettability of the microrobot and in the morphology of the loaded cells. An experiment was performed on a microfluidic chip for the simulation of blood flow environment, and result revealed that the cells adhered closely to the microrobot with NTS and were not obviously affected by flow. The cell viability and protein absorption test and alkaline phosphatase activity assay indicated that NTS can provide a regulatory means for improving cell proliferation and early osteogenic differentiation. This research provided a novel microrobotic platform that can positively influence the behaviour of cells loaded on microrobots through surface nanotopography, thereby opening up a new route for microrobot cell delivery.

COMPARISON OF ANTIHYPERTENSIVE EFFECT OF MOXONIDINE VERSUS CLONIDINE IN RENAL FAILURE PATIENTS.

2018 ◽  
Vol 6 (9) ◽  
Author(s):  
DR.MATHEW GEORGE ◽  
DR.LINCY JOSEPH ◽  
MRS.DEEPTHI MATHEW ◽  
ALISHA MARIA SHAJI ◽  
BIJI JOSEPH ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Renal Failure ◽  
Blood Flow ◽  
Blood Vessel ◽  
Blood Vessels ◽  
High Blood Pressure ◽  
Antihypertensive Effect ◽  
The Body ◽  
Ability To Work ◽  
Blood Flows

Blood pressure is the force of blood pushing against blood vessel walls as the heart pumps out blood, and high blood pressure, also called hypertension, is an increase in the amount of force that blood places on blood vessels as it moves through the body. Factors that can increase this force include higher blood volume due to extra fluid in the blood and blood vessels that are narrow, stiff, or clogged(1). High blood pressure can damage blood vessels in the kidneys, reducing their ability to work properly. When the force of blood flow is high, blood vessels stretch so blood flows more easily. Eventually, this stretching scars and weakens blood vessels throughout the body, including those in the kidneys.

Diaghilev and British Writing

2009 ◽  
Vol 27 (1) ◽  
pp. 65-92
Author(s):  
Susan Jones
Keyword(s):  
Visual Arts ◽  
The Body ◽  
The Novel ◽  
Literary Responses ◽  
Literary Aesthetics ◽  
Ballets Russes ◽  
The Arts ◽  
The Subject ◽  
And Gender ◽  
Opening Up

This article explores the diversity of British literary responses to Diaghilev's project, emphasising the way in which the subject matter and methodologies of Diaghilev's modernism were sometimes unexpectedly echoed in expressions of contemporary British writing. These discussions emerge both in writing about Diaghilev's work, and, more discretely, when references to the Russian Ballet find their way into the creative writing of the period, serving to anchor the texts in a particular cultural milieu or to suggest contemporary aesthetic problems in the domain of literary aesthetics developing in the period. Figures from disparate fields, including literature, music and the visual arts, brought to their criticism of the Ballets Russes their individual perspectives on its aesthetics, helping to consolidate the sense of its importance in contributing to the inter-disciplinary flavour of modernism across the arts. In the field of literature, not only did British writers evaluate the Ballets Russes in terms of their own poetics, their relationship to experimentation in the novel and in drama, they developed an increasing sense of the company's place in dance history, its choreographic innovations offering material for wider discussions, opening up the potential for literary modernism's interest in impersonality and in the ‘unsayable’, discussions of the body, primitivism and gender.

scholarly journals Ferromagnetic soft catheter robots for minimally invasive bioprinting

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Cheng Zhou ◽  
Youzhou Yang ◽  
Jiaxin Wang ◽  
Qingyang Wu ◽  
Zhuozhi Gu ◽  
...  
Keyword(s):  
Minimally Invasive ◽  
The Body ◽  
Magnetic Actuation ◽  
Internal Organs ◽  
Planar Surfaces ◽  
Reinforced Polymer ◽  
Direct Fabrication ◽  
Digitally Controlled

AbstractIn vivo bioprinting has recently emerged as a direct fabrication technique to create artificial tissues and medical devices on target sites within the body, enabling advanced clinical strategies. However, existing in vivo bioprinting methods are often limited to applications near the skin or require open surgery for printing on internal organs. Here, we report a ferromagnetic soft catheter robot (FSCR) system capable of in situ computer-controlled bioprinting in a minimally invasive manner based on magnetic actuation. The FSCR is designed by dispersing ferromagnetic particles in a fiber-reinforced polymer matrix. This design results in stable ink extrusion and allows for printing various materials with different rheological properties and functionalities. A superimposed magnetic field drives the FSCR to achieve digitally controlled printing with high accuracy. We demonstrate printing multiple patterns on planar surfaces, and considering the non-planar surface of natural organs, we then develop an in situ printing strategy for curved surfaces and demonstrate minimally invasive in vivo bioprinting of hydrogels in a rat model. Our catheter robot will permit intelligent and minimally invasive bio-fabrication.

scholarly journals Calculating the optimal hematocrit under the constraint of constant cardiac power

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Michal Sitina ◽  
Heiko Stark ◽  
Stefan Schuster
Keyword(s):  
Blood Flow ◽  
High Performance ◽  
Animal Species ◽  
Normal Values ◽  
Mechanical Load ◽  
The Body ◽  
Trade Off ◽  
Cardiac Power ◽  
Optimal Value ◽  
Good Agreement

AbstractIn humans and higher animals, a trade-off between sufficiently high erythrocyte concentrations to bind oxygen and sufficiently low blood viscosity to allow rapid blood flow has been achieved during evolution. Optimal hematocrit theory has been successful in predicting hematocrit (HCT) values of about 0.3–0.5, in very good agreement with the normal values observed for humans and many animal species. However, according to those calculations, the optimal value should be independent of the mechanical load of the body. This is in contradiction to the exertional increase in HCT observed in some animals called natural blood dopers and to the illegal practice of blood boosting in high-performance sports. Here, we present a novel calculation to predict the optimal HCT value under the constraint of constant cardiac power and compare it to the optimal value obtained for constant driving pressure. We show that the optimal HCT under constant power ranges from 0.5 to 0.7, in agreement with observed values in natural blood dopers at exertion. We use this result to explain the tendency to better exertional performance at an increased HCT.

scholarly journals Acupuncture Affects Regional Blood Flow in Various Organs

2008 ◽  
Vol 5 (2) ◽  
pp. 145-151 ◽  
Author(s):  
Sae Uchida ◽  
Harumi Hotta
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
The Body ◽  
Neural Mechanisms ◽  
Uterine Blood Flow ◽  
Afferent Pathway ◽  
Antidromic Activation ◽  
Efferent Nerve ◽  
Afferent Nerves ◽  
Cortical Cerebral Blood Flow

In this review, our recent studies using anesthetized animals concerning the neural mechanisms of vasodilative effect of acupuncture-like stimulation in various organs are briefly summarized. Responses of cortical cerebral blood flow and uterine blood flow are characterized as non-segmental and segmental reflexes. Among acupuncture-like stimuli delivered to five different segmental areas of the body; afferent inputs to the brain stem (face) and to the spinal cord at the cervical (forepaw), thoracic (chest or abdomen), lumbar (hindpaw) and sacral (perineum) levels, cortical cerebral blood flow was increased by stimuli to face, forepaw and hindpaw. The afferent pathway of the responses is composed of somatic groups III and IV afferent nerves and whose efferent nerve pathway includes intrinsic cholinergic vasodilators originating in the basal forebrain. Uterine blood flow was increased by cutaneous stimulation of the hindpaw and perineal area, with perineal predominance. The afferent pathway of the response is composed of somatic group II, III and IV afferent nerves and the efferent nerve pathway includes the pelvic parasympathetic cholinergic vasodilator nerves. Furthermore, we briefly summarize vasodilative regulation of skeletal muscle blood flow via a calcitonin gene-related peptide (CGRP) induced by antidromic activation of group IV somatic afferent nerves. These findings in healthy but anesthetized animals may be applicable to understanding the neural mechanisms improving blood flow in various organs following clinical acupuncture.

scholarly journals Chinese Herbal Medicine Alleviates Thyroidectomy-Induced Cardiopulmonary Exercise Dysfunction in Rats

2020 ◽  
Vol 2020 ◽  
pp. 1-8 ◽  
Author(s):  
Tai-Yuan Chuang ◽  
Chia-Ying Lien ◽  
Chih-Hsiang Hsu ◽  
Chen-Wen Lu ◽  
Chung-Hsin Wu
Keyword(s):  
Blood Flow ◽  
Body Weight ◽  
Negative Control ◽  
The Body ◽  
Male Rats ◽  
Free Triiodothyronine ◽  
Cardiopulmonary Exercise ◽  
Chinese Herbal ◽  
Subcutaneous Blood Flow ◽  
Tsh Levels

Hypothyroidism frequently causes cardiopulmonary dysfunction, such as heart failure and respiratory and metabolic deficiencies. This study investigated the effects of Chinese herbal formula B307 on thyroidectomy-induced cardiopulmonary exercise dysfunction in rats. Twenty male rats were equally divided into four groups: negative control with sham treatment, positive control with oral B307 treatment only, thyroidectomy treatment only, and thyroidectomy with B307 posttreatment groups. The feeding dose of B307 was 50 mg/kg per day for 14 days. We examined and then compared the thyroid-stimulating hormone (TSH), free triiodothyronine (T3), free thyroxine (T4), and reactive oxygen species (ROS) from the blood of these four groups. Also, we compared the body weight, neck subcutaneous blood flow, cardiac ejection function, cardiopulmonary exercise function of oxygen consumption (VO2), carbon dioxide production (VCO2), and respiratory quotient (RQ = VCO2/VO2) among the four groups. Our results indicated that thyroidectomized rats had significantly decreased body weight, neck subcutaneous blood flow, cardiac ejection function, serum T3 and T4, and VO2 and VCO2, but had significantly increased ROS and TSH levels and RQ values compared with sham rats (P<0.01–0.05). In addition, thyroidectomized rats receiving oral B307 treatment had significantly increased body weight, neck subcutaneous blood flow, cardiac ejection function, and VO2, but significantly decreased ROS and TSH levels and VCO2 and RQ values compared with thyroidectomized rats (P<0.01–0.05). We suggest that the B307 could be a protective and beneficial alternative treatment for thyroidectomy-induced cardiopulmonary exercise dysfunction.

Regional blood flow measurement in vivo for a definable geometry

1964 ◽  
Vol 206 (5) ◽  
pp. 962-966 ◽  
Author(s):  
Marvin B. Bacaner ◽  
James S. Beck
Keyword(s):  
Blood Flow ◽  
Flow Measurement ◽  
Necessary Conditions ◽  
Regional Blood Flow ◽  
The Body ◽  
Continuous Measure ◽  
Radioisotope Method ◽  
Arterial Concentration ◽  
Regional Concentration

A radioisotope method for measuring regional blood flow in the intestine of the dog in vivo has been favorably compared with measurement by timed collection of total venous outflow. The necessary conditions are a continuous measure of arterial concentration and cumulative regional concentration of radioisotope, an experimentally definable region, and temporary complete retention of tracer. The derivation of the relations used suggests additional applications of the method to other regions of the body.

A NUMERICAL STUDY ON THE HEMODYNAMIC AND SHEAR STRESS OF DOUBLE ANEURYSM THROUGH S-SHAPED VESSEL

2015 ◽  
Vol 27 (04) ◽  
pp. 1550033 ◽  
Author(s):  
Mahdi Halabian ◽  
Alireza Karimi ◽  
Borhan Beigzadeh ◽  
Mahdi Navidbakhsh
Keyword(s):  
Blood Flow ◽  
Mechanical Behavior ◽  
Numerical Study ◽  
Flow Characteristics ◽  
Flow Simulation ◽  
The Body ◽  
Sweep Angle ◽  
Abdominal Aortic ◽  
Hemodynamic Characteristics ◽  
Refined Meshes

Abdominal aortic aneurysm (AAA) is a degenerative disease defined as the abnormal ballooning of the abdominal aorta (AA) wall which is usually caused by atherosclerosis. The aneurysm grows larger and eventually ruptures if it is not diagnosed and treated. Aneurysms occur mostly in the aorta, the main artery of the chest and abdomen. The aorta carries blood flow from the heart to all parts of the body, including the vital organs, the legs, and feet. The objective of the present study is to investigate the combined effects of aneurysm and curvature on flow characteristics in S-shaped bends with sweep angle of 90° at Reynolds number of 900. The fluid mechanics of blood flow in a curved artery with abnormal aortic is studied through a mathematical analysis and employing Cosmos flow simulation. Blood is modeled as an incompressible non-Newtonian fluid and the flow is assumed to be steady and laminar. Hemodynamic characteristics are analyzed. Grid independence is tested on three successively refined meshes. It is observed that the abrupt expansion induced by AAA results in an immensely disturbed regime. The results may have implications not only for understanding the mechanical behavior of the blood flow inside an aneurysm artery but also for investigating the mechanical behavior of the blood flow in different arterial diseases, such as atherosclerosis.

Glucose and fatty acid metabolism in cows producing milk of low fat content

1974 ◽  
Vol 82 (1) ◽  
pp. 87-95 ◽  
Author(s):  
E. F. Annison ◽  
R. Bickerstaffe ◽  
J. L. Linzell
Keyword(s):  
Blood Flow ◽  
Milk Fat ◽  
The Body ◽  
Whole Body ◽  
Acetate Production ◽  
Entry Rate ◽  
Blood Concentrations ◽  
Body Tissues ◽  
High Starch ◽  
Starch Diet

SUMMARYThe effects of changing to a high starch: low roughage diet have been studied in two Friesian and two Jersey cows, surgically prepared for the simultaneous study of udder metabolism (arteriovenous difference x udder blood flow) and whole body turnover of milk precursors (isotope dilution).In the Friesian cows milk fat concentration was lower on the high starch diet but in the Jerseys fell only slightly in one animal. In both Friesians and in the one Jersey these changes were accompanied by an increase in total rumen VFA concentration. Rumen acetate concentration did not change but propionate doubled. Thus this confirms that the usually reported fall in ‘acetate:propionate ratio’ is due to a rise in propionate production rather than due to a fall in acetate production.There were significant falls in the blood concentrations of acetate and β-hydroxy-butyrate. The rate of extraction by the udder of acetate and β-hydroxybutyrate did not change but triglyceride extraction fell. Therefore since udder blood flow did not alter the uptake of all three fat precursors fell.The entry rate of glucose into the circulation and its contribution to total body CO2 increased. The entry rate and contribution to CO2 of acetate decreased but this was probably mainly due to a fall in endogenous acetate production by the body tissues. Plasma FFA concentration showed little change but the entry rate of palmitate fell on the high starch diet. There was also an increased proportion of unsaturated and trans fatty acids in the plasma and milk triglycerides.

Electromechanical Control of Atrium Function

2009 ◽  
Author(s):  
Miroslava Svobodova ◽  
Elena S. Di Martino
Keyword(s):  
Atrial Fibrillation ◽  
Blood Flow ◽  
Cardiac Function ◽  
The Body ◽  
Pump Function ◽  
Physical Systems ◽  
Electrical Systems ◽  
Mechanical Pump

The heart is a very efficient mechanical pump whose function is to controls the blood flow in the body. Two physical systems, namely mechanical for the pumping action and electrical for the control interact within the heart. Cardiac function can only be studied if both mechanical and electrical systems are considered. In particular, we are interested in the electromechanical control of the atrium pump function which is less studied then the electromechanical control of the ventricle pump function and none the less is a crucial factor in the development of atrial fibrillation.

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