Recordings of Impedance and Communication Between Defibrillator and Pacemaker Electrodes

2019 ◽  
Vol 8 (2) ◽  
pp. 45-68
Author(s):  
Anders Jarløv ◽  
Anne Elisabeth Jarløv ◽  
Tim Toftgaard Jensen
Keyword(s):  
Heart Muscle ◽  
Normal Activity ◽  
The Body ◽  
Porcine Heart ◽  
Natural Activity ◽  
Conductive Materials ◽  
Conductive Medium ◽  
Electric Shocks ◽  
Pacemaker Electrodes

External defibrillation involves short electric shocks of several thousand volts applied to the chest of patients suffering from heart stop. The shock coordinates disorganized muscle fibers of the heart which then can resume normal activity. Implanted pacemakers monitor the natural electrical activity of the heart via electrodes mounted permanently on the inside of the heart. If this activity is insufficient, the pacemaker stimulates the heart muscle by applying a short electrical impulse of a few volts. During the period of defibrillation, voltage differences arise simultaneously between various locations of the body preventing recordings of the heart's natural activity. In order to quantify parameters determining voltage and current in a conductive medium or in a myocardium when defibrillator and pacemaker electrodes are present simultaneously, impedances between electrodes positioned on conductive materials were recorded in laboratory set ups, and the methods were tested using a porcine heart in vitro.

The Role of Polyphenols in the Modulation of Plasma Non-Enzymatic Antioxidant Capacity (NEAC)

2012 ◽  
Vol 82 (3) ◽  
pp. 228-232 ◽  
Author(s):  
Mauro Serafini ◽  
Giuseppa Morabito
Keyword(s):  
Antioxidant Capacity ◽  
Dietary Intervention ◽  
Ex Vivo ◽  
The Body ◽  
Dietary Polyphenols ◽  
Enzymatic Antioxidant ◽  
Endogenous Antioxidant

Dietary polyphenols have been shown to scavenge free radicals, modulating cellular redox transcription factors in different in vitro and ex vivo models. Dietary intervention studies have shown that consumption of plant foods modulates plasma Non-Enzymatic Antioxidant Capacity (NEAC), a biomarker of the endogenous antioxidant network, in human subjects. However, the identification of the molecules responsible for this effect are yet to be obtained and evidences of an antioxidant in vivo action of polyphenols are conflicting. There is a clear discrepancy between polyphenols (PP) concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the endogenous antioxidant network. This work will discuss the role of polyphenols from galenic preparation, food extracts, and selected dietary sources as modulators of plasma NEAC in humans.

A Simple and Inexpensive Clinical Whole Body Counter

1976 ◽  
Vol 15 (05) ◽  
pp. 248-253
Author(s):  
A. K. Basu ◽  
S. K. Guha ◽  
B. N. Tandon ◽  
M. M. Gupta ◽  
M. ML. Rehani
Keyword(s):  
The Body ◽  
Whole Body ◽  
Vitro Assay ◽  
Body Counter ◽  
Optimum Parameters ◽  
Whole Body Counter ◽  
Single Detector ◽  
Background Index ◽  
Iodide Crystal

SummaryThe conventional radioisotope scanner has been used as a whole body counter. The background index of the system is 10.9 counts per minute per ml of sodium iodide crystal. The sensitivity and derived sensitivity parameters have been evaluated and found to be suitable for clinical studies. The optimum parameters for a single detector at two positions above the lying subject have been obtained. It has been found that for the case of 131I measurement it is possible to assay a source located at any point in the body with coefficient of variation less than 5%. To add to the versatility, a fixed geometry for in-vitro counting of large samples has been obtained. The retention values obtained by the whole body counter have been found to correlate with those obtained by in-vitro assay of urine and stool after intravenous administration of 51Cr-albumin.

Preparation and In Vitro Evaluation of Resealed Erythrocytes as A New Trend in Treatment of Asthma

2016 ◽  
Vol 6 (3) ◽  
Author(s):  
Mohammed Ibrahim ◽  
Alaa Zaky ◽  
Mohsen Afouna ◽  
Ahmed Samy
Keyword(s):  
In Vitro Release ◽  
Human Erythrocytes ◽  
The Body ◽  
Blood Levels ◽  
Time Interval ◽  
Burst Release ◽  
Prolonged Release ◽  
Nocturnal Asthma ◽  
Carrier Erythrocytes

Carrier erythrocytes are emerging as one of the most promising biological drug delivery systems investigated in recent decades. Beside its biocompatibility, biodegradability and ability to circulate throughout the body, it has the ability to perform extended release system of the drug for a long period. The ultimate goal of this study is to introduce a new carrier system for Salbutamol, maintaining suitable blood levels for a long time, as atrial to resolve the problems of nocturnal asthma medication Therefore in this work we study the effect of time, temperature as well as concentration on the loading of salbutamol in human erythrocytes to be used as systemic sustained release delivery system for this drug. After the loading process is performed the carrier erythrocytes were physically and cellulary characterized. Also, the in vitro release of salbutamol from carrier erythrocytes was studied over time interval. From the results it was found that, human erythrocytes have been successfully loaded with salbutamol using endocytosis method either at 25 Co or at 37 Co . The highest loaded amount was 3.5 mg/ml and 6.5 mg/ml respectively. Moreover, the percent of cells recovery is 90.7± 1.64%. Hematological parameters and osmotic fragility behavior of salbutamol loaded erythrocytes were similar that of native erythrocytes. Scanning electron microscopy demonstrated that the salbutamol loaded cells has moderate change in the morphology. Salbutamol releasing from carrier cell was 43% after 36 hours in phosphate buffer saline. The releasing pattern of the drug from loaded erythrocytes showed initial burst release in the first hour followed by a very slow release, obeying zero order kinetics. It concluded that salbutamol is successfully entrapped into erythrocytes with acceptable loading parameters and moderate morphological changes, this suggesting that erythrocytes can be used as prolonged release carrier for salbutamol.

Репрограммированые in vitro на М3 фенотип макрофаги останавливают рост солидной карциномы in vivo

2018 ◽  
pp. 41-46
Author(s):  
А.А. Раецкая ◽  
С.В. Калиш ◽  
С.В. Лямина ◽  
Е.В. Малышева ◽  
О.П. Буданова ◽  
...  
Keyword(s):  
Solid Tumor ◽  
Antitumor Effect ◽  
Tumor Development ◽  
Significant Inhibition ◽  
The Body ◽  
Ehrlich Carcinoma ◽  
Solid Carcinoma ◽  
Ec Cells

Цель исследования. Доказательство гипотезы, что репрограммированные in vitro на М3 фенотип макрофаги при введении в организм будут существенно ограничивать развитие солидной карциномы in vivo . Методика. Рост солидной опухоли инициировали у мышей in vivo путем подкожной инъекции клеток карциномы Эрлиха (КЭ). Инъекцию макрофагов с нативным М0 фенотипом и с репрограммированным M3 фенотипом проводили в область формирования солидной КЭ. Репрограммирование проводили с помощью низких доз сыворотки, блокаторов факторов транскрипции STAT3/6 и SMAD3 и липополисахарида. Использовали две схемы введения макрофагов: раннее и позднее. При раннем введении макрофаги вводили на 1-е, 5-е, 10-е и 15-е сут. после инъекции клеток КЭ путем обкалывания макрофагами с четырех сторон область развития опухоли. При позднем введении, макрофаги вводили на 10-е, 15-е, 20-е и 25-е сут. Через 15 и 30 сут. после введения клеток КЭ солидную опухоль иссекали и измеряли ее объем. Эффект введения макрофагов оценивали качественно по визуальной и пальпаторной характеристикам солидной опухоли и количественно по изменению ее объема по сравнению с группой без введения макрофагов (контроль). Результаты. Установлено, что M3 макрофаги при раннем введении от начала развития опухоли оказывают выраженный антиопухолевый эффект in vivo , который был существенно более выражен, чем при позднем введении макрофагов. Заключение. Установлено, что введение репрограммированных макрофагов M3 ограничивает развитие солидной карциномы в экспериментах in vivo . Противоопухолевый эффект более выражен при раннем введении М3 макрофагов. Обнаруженные в работе факты делают перспективным разработку клинической версии биотехнологии ограничения роста опухоли, путем предварительного программирования антиопухолевого врожденного иммунного ответа «в пробирке». Aim. To verify a hypothesis that macrophages reprogrammed in vitro to the M3 phenotype and injected into the body substantially restrict the development of solid carcinoma in vivo . Methods. Growth of a solid tumor was initiated in mice in vivo with a subcutaneous injection of Ehrlich carcinoma (EC) cells. Macrophages with a native M0 phenotype or reprogrammed towards the M3 phenotype were injected into the region of developing solid EC. Reprogramming was performed using low doses of serum, STAT3/6 and SMAD3 transcription factor blockers, and lipopolysaccharide. Two schemes of macrophage administration were used: early and late. With the early administration, macrophages were injected on days 1, 5, 10, and 15 following the injection of EC cells at four sides of the tumor development area. With the late administration, macrophages were injected on days 10, 15, 20, and 25. At 15 and 30 days after the EC cell injection, the solid tumor was excised and its volume was measured. The effect of macrophage administration was assessed both qualitatively by visual and palpation characteristics of solid tumor and quantitatively by changes in the tumor volume compared with the group without the macrophage treatment. Results. M3 macrophages administered early after the onset of tumor development exerted a pronounced antitumor effect in vivo , which was significantly greater than the antitumor effect of the late administration of M3 macrophages. Conclusion. The observed significant inhibition of in vivo growth of solid carcinoma by M3 macrophages makes promising the development of a clinical version of the biotechnology for restriction of tumor growth by in vitro pre-programming of the antitumor, innate immune response.

Neural Stem Cells to Glial Cells an Important Factor for Brain Injury

2020 ◽  
Author(s):  
Prithiv K R Kumar
Keyword(s):  
Stem Cells ◽  
Central Nervous System ◽  
Nervous System ◽  
Neural Stem Cells ◽  
Glial Cells ◽  
Brain Injuries ◽  
The Body ◽  
The Central Nervous System ◽  
Near Future

Stem cells have the capacity to differentiate into any type of cell or organ. Stems cell originate from any part of the body, including the brain. Brain cells or rather neural stem cells have the capacitive advantage of differentiating into the central nervous system leading to the formation of neurons and glial cells. Neural stem cells should have a source by editing DNA, or by mixings chemical enzymes of iPSCs. By this method, a limitless number of neuron stem cells can be obtained. Increase in supply of NSCs help in repairing glial cells which in-turn heal the central nervous system. Generally, brain injuries cause motor and sensory deficits leading to stroke. With all trials from novel therapeutic methods to enhanced rehabilitation time, the economy and quality of life is suppressed. Only PSCs have proven effective for grafting cells into NSCs. Neurons derived from stem cells is the only challenge that limits in-vitro usage in the near future.

Nanocurcumin: A Double-Edged Sword for Microcancers

2020 ◽  
Vol 26 (45) ◽  
pp. 5783-5792
Author(s):  
Kholood Abid Janjua ◽  
Adeeb Shehzad ◽  
Raheem Shahzad ◽  
Salman Ul Islam ◽  
Mazhar Ul Islam
Keyword(s):  
Intracellular Signaling ◽  
Dosage Forms ◽  
The Body ◽  
In Vivo Studies ◽  
Mrna Levels ◽  
Anticancer Activities ◽  
Road Map ◽  
Anticancer Effects

There is compelling evidence that drug molecules isolated from natural sources are hindered by low systemic bioavailability, poor absorption, and rapid elimination from the human body. Novel approaches are urgently needed that could enhance the retention time as well as the efficacy of natural products in the body. Among the various adopted approaches to meet this ever-increasing demand, nanoformulations show the most fascinating way of improving the bioavailability of dietary phytochemicals through modifying their pharmacokinetics and pharmacodynamics. Curcumin, a yellowish pigment isolated from dried ground rhizomes of turmeric, exhibits tremendous pharmacological effects, including anticancer activities. Several in vitro and in vivo studies have shown that curcumin mediates anticancer effects through the modulation (upregulation and/or downregulations) of several intracellular signaling pathways both at protein and mRNA levels. Scientists have introduced multiple modern techniques and novel dosage forms for enhancing the delivery, bioavailability, and efficacy of curcumin in the treatment of various malignancies. These novel dosage forms include nanoparticles, liposomes, micelles, phospholipids, and curcumin-encapsulated polymer nanoparticles. Nanocurcumin has shown improved anticancer effects compared to conventional curcumin formulations. This review discusses the underlying molecular mechanism of various nanoformulations of curcumin for the treatment of different cancers. We hope that this study will make a road map for preclinical and clinical investigations of cancer and recommend nano curcumin as a drug of choice for cancer therapy.

Nanoparticles and Its Implications in HIV/AIDS Therapy

2020 ◽  
Vol 17 (4) ◽  
pp. 448-456 ◽  
Author(s):  
Victor B. Oti
Keyword(s):  
Direct Injection ◽  
Oral Intake ◽  
Public Health Problem ◽  
Antiretroviral Drugs ◽  
The Body ◽  
Viral Agent ◽  
Treatment And Prevention ◽  
Prevention And Treatment ◽  
Hiv Aids

The use of Antiretroviral drugs in treating HIV/ AIDS patients has enormously increased their life spans with serious disadvantages. The virus infection still remains a public health problem worldwide with no cure and vaccine for the viral agent until now. The use of nanoparticles (NPs) for the treatment and prevention of HIV/AIDS is an emerging technology of the 21st century. NPs are solid and colloid particles with 10 nm to <1000 nm size range; although, less than 200 nm is the recommended size for nanomedical usage. There are NPs with therapeutic capabilities such as liposomes, micelles, dendrimers and nanocapsules. The particle enters the body mainly via oral intake, direct injection and inhalation. It has been proven to have potentials of advancing the prevention and treatment of the viral agent. Certain NPs have been shown to have selftherapeutic activity for the virus in vitro. Strategies that are novel are emerging which can be used to improve nanotechnology, such as genetic treatment and immunotherapy. In this review, nanoparticles, the types and its characteristics in drug delivery were discussed. The light was furthermore shed on its implications in the prevention and treatment of HIV/AIDS.

a Novel Combinational Nanodrug Delivery System Induces Synergistic Inhibition of Lung Adenocarcinoma Cells in vitro

2020 ◽  
Vol 17 ◽  
Author(s):  
Mingliang Fan ◽  
Jiping Li
Keyword(s):  
Lung Adenocarcinoma ◽  
Delivery System ◽  
The Body ◽  
Anticancer Efficacy ◽  
Nanodrug Delivery ◽  
Drug Molecules ◽  
Cellular Assays ◽  
Lung Adenocarcinoma Cell Line ◽  
M Phase

Background: The combination of two or more therapeutic drugs is an attractive approach to improve the treatment of experimental tumors. Leveraging nanocarriers for combinational drug delivery can allow a control over drug biological fate and promote co-localization in the same area of the body. However, there are certain concerns regarding the biodegradability and potential long-term toxicity arising from these synthetic nanoscale carriers. Objective: Our aim was to develop a combinational nanodrug delivery system formed by self-assembling of amphiphilic drug molecules，minimizing potential toxicities associated with using additional synthetic nanocarriers. Methods: A novel prodrug chlorambucil gemcitabine conjugate was synthesized, this prodrug was used for the encapsulation of an additional hydrophobic anticancer drug paclitaxel, taking the form of combinational nanodrugs. Particle size and zeta potential were evaluated, cytotoxicity assay and apoptosis/cell cycle analysis were also performed to validate the anticancer efficacy of the combinational nanodrugs. Results: The combinational nanodrugs were acquired by means of nanoprecipitation. In A549 lung adenocarcinoma cell line, cellular assays revealed that co-delivery of low dosage paclitaxel with chlorambucil gemcitabine conjugate can act synergistically to inhibit cell growth and induce accumulation of cells in the G2/M phase with a concomitant decrease in G0/G1 compartment. Conclusion: Chlorambucil gemcitabine conjugate and paclitaxel can co-assemble into composite nanoparticles by a nanoprecipitation process and the resulting combinational nanodrugs showed synergistic anticancer effect. This synthetic nanocarrier-free approach might broaden the nanodrug concept and have potential in cancer therapy.

scholarly journals Perilla frutescens Leaf Extract and Fractions: Polyphenol Composition, Antioxidant, Enzymes (α-Glucosidase, Acetylcholinesterase, and Tyrosinase) Inhibitory, Anticancer, and Antidiabetic Activities

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 315
Author(s):  
Zhenxing Wang ◽  
Zongcai Tu ◽  
Xing Xie ◽  
Hao Cui ◽  
Kin Weng Kong ◽  
...  
Keyword(s):  
Ethyl Acetate ◽  
Animal Experiments ◽  
Ethyl Acetate Fraction ◽  
The Body ◽  
Total Phenolic ◽  
Antioxidant Power ◽  
Glycogen Accumulation ◽  
Inhibitory Ability

This study aims to evaluate the bioactive components, in vitro bioactivities, and in vivo hypoglycemic effect of P. frutescens leaf, which is a traditional medicine-food homology plant. P. frutescens methanol crude extract and its fractions (petroleum ether, chloroform, ethyl acetate, n-butanol fractions, and aqueous phase residue) were prepared by ultrasound-enzyme assisted extraction and liquid–liquid extraction. Among the samples, the ethyl acetate fraction possessed the high total phenolic (440.48 μg GAE/mg DE) and flavonoid content (455.22 μg RE/mg DE), the best antioxidant activity (the DPPH radical, ABTS radical, and superoxide anion scavenging activity, and ferric reducing antioxidant power were 1.71, 1.14, 2.40, 1.29, and 2.4 times higher than that of control Vc, respectively), the most powerful α-glucosidase inhibitory ability with the IC50 value of 190.03 μg/mL which was 2.2-folds higher than control acarbose, the strongest proliferative inhibitory ability against MCF-7 and HepG2 cell with the IC50 values of 37.92 and 13.43 μg/mL, which were considerable with control cisplatin, as well as certain inhibition abilities on acetylcholinesterase and tyrosinase. HPLC analysis showed that the luteolin, rosmarinic acid, rutin, and catechin were the dominant components of the ethyl acetate fraction. Animal experiments further demonstrated that the ethyl acetate fraction could significantly decrease the serum glucose level, food, and water intake of streptozotocin-induced diabetic SD rats, increase the body weight, modulate their serum levels of TC, TG, HDL-C, and LDL-C, improve the histopathology and glycogen accumulation in liver and intestinal tissue. Taken together, P. frutescens leaf exhibits excellent hypoglycemic activity in vitro and in vivo, and could be exploited as a source of natural antidiabetic agent.

scholarly journals Collagen-Based Electrospun Materials for Tissue Engineering: A Systematic Review

2021 ◽  
Vol 8 (3) ◽  
pp. 39
Author(s):  
Britani N. Blackstone ◽  
Summer C. Gallentine ◽  
Heather M. Powell
Keyword(s):  
Systematic Review ◽  
Tissue Engineering ◽  
Collagen Type I ◽  
The Body ◽  
Pool Data ◽  
Type I ◽  
High Concentrations ◽  
Increased Strength

Collagen is a key component of the extracellular matrix (ECM) in organs and tissues throughout the body and is used for many tissue engineering applications. Electrospinning of collagen can produce scaffolds in a wide variety of shapes, fiber diameters and porosities to match that of the native ECM. This systematic review aims to pool data from available manuscripts on electrospun collagen and tissue engineering to provide insight into the connection between source material, solvent, crosslinking method and functional outcomes. D-banding was most often observed in electrospun collagen formed using collagen type I isolated from calfskin, often isolated within the laboratory, with short solution solubilization times. All physical and chemical methods of crosslinking utilized imparted resistance to degradation and increased strength. Cytotoxicity was observed at high concentrations of crosslinking agents and when abbreviated rinsing protocols were utilized. Collagen and collagen-based scaffolds were capable of forming engineered tissues in vitro and in vivo with high similarity to the native structures.

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