A Simple Silicon Based Nitric Oxide Sensor

1999 ◽  
Author(s):  
Marcelo Bariatto ◽  
Rogerio Furlan ◽  
Koiti Arakai ◽  
Jorge J. Santiago-Aviles
Keyword(s):  
Nitric Oxide ◽  
Amperometric Detection ◽  
Cellular Level ◽  
High Yield ◽  
Sensor Calibration ◽  
Nitric Oxide Sensor ◽  
Sensor Configuration

Abstract Nitric oxide (NO) is known to mediate many beneficial physiology processes, motivating its detection in vivo as well as in vitro. Electrochemical detection provides the required cellular level determination of NO among several other techniques. In this work, electrochemical micro-sensors for both types of detection, in vivo and in vitro, were developed, exploring the silicon planar technology, which presents high yield and reliability and also permits batch fabrication. The developed in vitro sensor features eight detection sites (10 μm × 10 μm microelectrodes), for determination of nitric oxide spatial distribution or multi-species analysis. Different electrochemical methods were applied to provide sensor calibration and chemical reproducibility. For in vivo analysis, the designed structures have a needle shape (40 μm thick) and they were silicon micro-machined by using plasma etching or etch stop techniques. Different configurations were designed and implemented, containing a number of detection microelectrodes that vary from 2 to 10. The amperometric detection of both nitric oxide and nitride (NO2−) — a molecule that causes an interference — were investigated by using the in vitro micro-sensor configuration. The need of a cationic exchanger (Nafion) was demonstrated in order to provide selectivity to NO for low concentrations. Also, the developed sensor has a sensitivity of 500 A/M.cm2 and a detection limit of 10 μM.

A Molecular Approach to Immunoscintigraphy: A Study of the T-Antigen Conformation on the Surface of Tumors

1987 ◽  
Vol 26 (01) ◽  
pp. 1-6 ◽  
Author(s):  
S. Selvaraj ◽  
M. R. Suresh ◽  
G. McLean ◽  
D. Willans ◽  
C. Turner ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Tumor Cell ◽  
T Antigen ◽  
Human Carcinomas ◽  
Animal Tumor ◽  
Synthetic Antigens

The role of glycoconjugates in tumor cell differentiation has been well documented. We have examined the expression of the two anomers of the Thomsen-Friedenreich antigen on the surface of human, canine and murine tumor cell membranes both in vitro and in vivo. This has been accomplished through the synthesis of the disaccharide terminal residues in both a and ß configuration. Both entities were used to generate murine monoclonal antibodies which recognized the carbohydrate determinants. The determination of fine specificities of these antibodies was effected by means of cellular uptake, immunohistopathology and immunoscintigraphy. Examination of pathological specimens of human and canine tumor tissue indicated that the expressed antigen was in the β configuration. More than 89% of all human carcinomas tested expressed the antigen in the above anomeric form. The combination of synthetic antigens and monoclonal antibodies raised specifically against them provide us with invaluable tools for the study of tumor marker expression in humans and their respective animal tumor models.

Storage of Human Blood Platelets

1974 ◽  
Vol 32 (02/03) ◽  
pp. 405-416 ◽  
Author(s):  
M. R Hardeman ◽  
Carina J L. Heynens
Keyword(s):  
Storage Temperature ◽  
Platelet Rich Plasma ◽  
Blood Platelets ◽  
Storage Period ◽  
Serotonin Uptake ◽  
Hypotonic Shock ◽  
Glycolytic Intermediates

SummaryStorage experiments were performed at 4°, 25° and 37° C with platelet-rich plasma under sterile conditions. In some experiments also the effect of storing platelets at 4° C in whole blood was investigated.Before, during and after three days of storage, the platelets were tested at 37° C for their serotonin uptake and response to hypotonic shock. In addition some glycolytic intermediates were determined.A fair correlation was noticed between the serotonin uptake and hypotonic shock experiments. Both parameters were best maintained at 25° C. Also platelet counting, performed after the storage period, indicated 25° C as the best storage temperature. Determination of glycolytic intermediates did not justify any conclusion regarding the optimal storage temperature. Of the various anticoagulants studied, ACD and heparin gave the best results as to the serotonin uptake and hypotonic shock response, either with fresh or stored platelets. The use of EDTA resulted in the lowest activity, especially after storage.The results of these storage experiments in vitro, correspond well with those in vivo reported in the literature.

Exploiting Anti-Inflammation Effects of Flavonoids in Chronic Inflammatory Diseases

2020 ◽  
Vol 26 (22) ◽  
pp. 2610-2619 ◽  
Author(s):  
Tarique Hussain ◽  
Ghulam Murtaza ◽  
Huansheng Yang ◽  
Muhammad S. Kalhoro ◽  
Dildar H. Kalhoro
Keyword(s):  
Oxidative Stress ◽  
Chronic Diseases ◽  
Inflammatory Diseases ◽  
Therapeutic Option ◽  
Cellular Level ◽  
Antiinflammatory Drugs ◽  
Suitable Alternative ◽  
Chronic Inflammatory Diseases

Background: Inflammation is a complex response of the host defense system to different internal and external stimuli. It is believed that persistent inflammation may lead to chronic inflammatory diseases such as, inflammatory bowel disease, neurological and cardiovascular diseases. Oxidative stress is the main factor responsible for the augmentation of inflammation via various molecular pathways. Therefore, alleviating oxidative stress is effective a therapeutic option against chronic inflammatory diseases. Methods: This review article extends the knowledge of the regulatory mechanisms of flavonoids targeting inflammatory pathways in chronic diseases, which would be the best approach for the development of suitable therapeutic agents against chronic diseases. Results: Since the inflammatory response is initiated by numerous signaling molecules like NF-κB, MAPK, and Arachidonic acid pathways, their encountering function can be evaluated with the activation of Nrf2 pathway, a promising approach to inhibit/prevent chronic inflammatory diseases by flavonoids. Over the last few decades, flavonoids drew much attention as a potent alternative therapeutic agent. Recent clinical evidence has shown significant impacts of flavonoids on chronic diseases in different in-vivo and in-vitro models. Conclusion: Flavonoid compounds can interact with chronic inflammatory diseases at the cellular level and modulate the response of protein pathways. A promising approach is needed to overlook suitable alternative compounds providing more therapeutic efficacy and exerting fewer side effects than commercially available antiinflammatory drugs.

Carbon dots derived from Fusobacterium nucleatum for intracellular determination of Fe3+ and bioimaging both in vitro and in vivo

2021 ◽  
Author(s):  
Lijuan Liu ◽  
Shengting Zhang ◽  
Xiaodan Zheng ◽  
Hongmei Li ◽  
Qi Chen ◽  
...  
Keyword(s):  
Carbon Dots ◽  
Fusobacterium Nucleatum ◽  
Living Cells ◽  
First Time ◽  
Fluorescent Carbon Dots ◽  
Fluorescent Carbon

Fusobacterium nucleatum has been employed for the first time to synthesize fluorescent carbon dots which could be applied for the determination of Fe3+ ions in living cells and bioimaging in vitro and in vivo with excellent biocompatibility.

scholarly journals In Vitro and In Vivo Anti-Inflammatory Effects of Sulfated Polysaccharides Isolated from the Edible Brown Seaweed, Sargassum fulvellum

Marine Drugs ◽  
2021 ◽  
Vol 19 (5) ◽  
pp. 277
Author(s):  
Lei Wang ◽  
Hye-Won Yang ◽  
Ginnae Ahn ◽  
Xiaoting Fu ◽  
Jiachao Xu ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Brown Seaweed ◽  
Sulfated Polysaccharides ◽  
Raw 264.7 ◽  
Raw 264.7 Macrophages ◽  
Sargassum Fulvellum ◽  
Pharmaceutical Industries ◽  
Anti Inflammatory

In the present study, the in vitro and in vivo anti-inflammatory effects of the sulfated polysaccharides isolated from Sargassum fulvellum (SFPS) were evaluated in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and zebrafish. The results indicated that SFPS improved the viability of LPS-stimulated RAW 264.7 macrophages from 80.02 to 86.80, 90.09, and 94.62% at the concentration of 25, 50, and 100 µg/mL, respectively. Also, SFPS remarkably and concentration-dependently decreased the production levels of inflammatory molecules including nitric oxide (NO), tumor necrosis factor-alpha, prostaglandin E2, interleukin-1 beta, and interleukin-6 in LPS-treated RAW 264.7 macrophages. In addition, SFPS significantly inhibited the expression levels of cyclooxygenase-2 and inducible nitric oxide synthase in LPS-treated RAW 264.7 macrophages. Furthermore, the in vivo test results indicated that SFPS improved the survival rate of LPS-treated zebrafish from 53.33 to 56.67, 60.00, and 70.00% at the concentration of 25, 50, and 100 µg/mL, respectively. In addition, SFPS effectively reduced cell death, reactive oxygen species, and NO levels in LPS-stimulated zebrafish. Taken together, these results suggested that SFPS possesses strong in vitro and in vivo anti-inflammatory activities, and could be used as an ingredient to develop anti-inflammatory agents in the functional food and pharmaceutical industries.

scholarly journals Phaseolin Attenuates Lipopolysaccharide-Induced Inflammation in RAW 264.7 Cells and Zebrafish

Biomedicines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 420
Author(s):  
Su-Jung Hwang ◽  
Ye-Seul Song ◽  
Hyo-Jong Lee
Keyword(s):  
Nitric Oxide ◽  
Nuclear Translocation ◽  
Raw 264.7 Cells ◽  
Network Pharmacology ◽  
Raw 264.7 ◽  
Dependent Manner ◽  
Bioactive Constituents

Kushen (Radix Sophorae flavescentis) is used to treat ulcerative colitis, tumors, and pruritus. Recently, phaseolin, formononetin, matrine, luteolin, and quercetin, through a network pharmacology approach, were tentatively identified as five bioactive constituents responsible for the anti-inflammatory effects of S. flavescentis. However, the role of phaseolin (one of the primary components of S. flavescentis) in the direct regulation of inflammation and inflammatory processes is not well known. In this study, the beneficial role of phaseolin against inflammation was explored in lipopolysaccharide (LPS)-induced inflammation models of RAW 264.7 macrophages and zebrafish larvae. Phaseolin inhibited LPS-mediated production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS), without affecting cell viability. In addition, phaseolin suppressed pro-inflammatory mediators such as cyclooxygenase 2 (COX-2), interleukin-1β (IL-1β), tumor necrosis factor α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), and interleukin-6 (IL-6) in a dose-dependent manner. Furthermore, phaseolin reduced matrix metalloproteinase (MMP) activity as well as macrophage adhesion in vitro and the recruitment of leukocytes in vivo by downregulating Ninjurin 1 (Ninj1), an adhesion molecule. Finally, phaseolin inhibited the nuclear translocation of nuclear factor-kappa B (NF-κB). In view of the above, our results suggest that phaseolin could be a potential therapeutic candidate for the management of inflammation.

scholarly journals Novel Insights on the Role of Nitric Oxide in the Ovary: A Review of the Literature

2021 ◽  
Vol 18 (3) ◽  
pp. 980
Author(s):  
Maria Cristina Budani ◽  
Gian Mario Tiboni
Keyword(s):  
Nitric Oxide ◽  
In Vivo Studies ◽  
Published Data ◽  
Vitro Fertilization ◽  
Peripheral Neurons ◽  
Relevant Role ◽  
Oocyte Meiotic Maturation

Nitric oxide (NO) is formed during the oxidation of L-arginine to L-citrulline by the action of multiple isoenzymes of NO synthase (NOS): neuronal NOS (nNOS), endotelial NOS (eNOS), and inducible NOS (iNOS). NO plays a relevant role in the vascular endothelium, in central and peripheral neurons, and in immunity and inflammatory systems. In addition, several authors showed a consistent contribution of NO to different aspects of the reproductive physiology. The aim of the present review is to analyse the published data on the role of NO within the ovary. It has been demonstrated that the multiple isoenzymes of NOS are expressed and localized in the ovary of different species. More to the point, a consistent role was ascribed to NO in the processes of steroidogenesis, folliculogenesis, and oocyte meiotic maturation in in vitro and in vivo studies using animal models. Unfortunately, there are few nitric oxide data for humans; there are preliminary data on the implication of nitric oxide for oocyte/embryo quality and in-vitro fertilization/embryo transfer (IVF/ET) parameters. NO plays a remarkable role in the ovary, but more investigation is needed, in particular in the context of human ovarian physiology.

Factors affecting in vitro and in vivo antioxidant effects. Experimental conditions and nature of oxidants determine antioxidant efficacy

2021 ◽  
pp. 1-9
Author(s):  
Etsuo Niki
Keyword(s):  
Biological Molecules ◽  
Experimental Conditions ◽  
Factors Affecting ◽  
Beneficial Effects ◽  
Multiple Oxidants ◽  
Antioxidant Effects

Reactive oxygen and nitrogen species have been implicated in the onset and progression of various diseases and the role of antioxidants in the maintenance of health and prevention of diseases has received much attention. The action and effect of antioxidants have been studied extensively under different reaction conditions in multiple media. The antioxidant effects are determined by many factors. This review aims to discuss several important issues that should be considered for determination of experimental conditions and interpretation of experimental results in order to understand the beneficial effects and limit of antioxidants against detrimental oxidation of biological molecules. Emphasis was laid on cell culture experiments and effects of diversity of multiple oxidants on antioxidant efficacy.

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