scholarly journals Smartphone-powered iontophoresis-microneedle array patch for controlled transdermal delivery

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Jingbo Yang ◽  
Yanjun Li ◽  
Rui Ye ◽  
Ying Zheng ◽  
Xiangling Li ◽  
...  
Keyword(s):  
Transdermal Delivery ◽  
Insulin Delivery ◽  
Diabetic Rat ◽  
Microneedle Array ◽  
Control Drug ◽  
Control Of Diabetes ◽  
One Step ◽  
Glycemic Regulation

AbstractThe incidence rate of diabetes has been increasing every year in nearly all nations and regions. The traditional control of diabetes using transdermal insulin delivery by metal needles is generally associated with pain and potential infections. While microneedle arrays (MAs) have emerged as painless delivery techniques, the integration of MA systems with electronic devices to precisely control drug delivery has rarely been realized. In this study, we developed an iontophoresis-microneedle array patch (IMAP) powered by a portable smartphone for the active and controllable transdermal delivery of insulin. The IMAP in situ integrates iontophoresis and charged nanovesicles into one patch, achieving a one-step drug administration strategy of “penetration, diffusion and iontophoresis”. The MA of the IMAP is first pressed on the skin to create microholes and then is retracted, followed by the iontophoresis delivery of insulin-loaded nanovesicles through these microholes in an electrically controlled manner. This method has synergistically and remarkably enhanced controlled insulin delivery. The amount of insulin can be effectively regulated by the IMAP by applying different current intensities. This in vivo study has demonstrated that the IMAP effectively delivers insulin and produces robust hypoglycemic effects in a type-1 diabetic rat model, with more advanced controllability and efficiency than delivery by a pristine microneedle or iontophoresis. The IMAP system shows high potential for diabetes therapy and the capacity to provide active as well as long-term glycemic regulation without medical staff care.

Glycemic Regulation Using a Programmed Insulin Delivery Device: III. Long-Term Studies on Diabetic Dogs

Diabetes ◽  
1979 ◽  
Vol 28 (6) ◽  
pp. 558-564 ◽  
Author(s):  
Y. Goriya ◽  
A. Bahoric ◽  
E. B. Marliss ◽  
B. Zinman ◽  
A. M. Albisser
Keyword(s):  
Insulin Delivery ◽  
Delivery Device ◽  
Diabetic Dogs ◽  
Glycemic Regulation ◽  
Long Term Studies

EVIDENCE FOR PLASMIN-MEDIATED FIBRINOLYSIS AFTER /RELEASE OF TISSUE PLASMINOGEN ACTIVATOR BY DESMOPRESSIN INFUSION

1987 ◽  
Author(s):  
G D O Lowe ◽  
J T Douglas ◽  
M Small ◽  
C Kluft ◽  
C D Forbes
Keyword(s):  
Plasminogen Activator ◽  
Venous Blood ◽  
Term Treatment ◽  
Fibrin Plate ◽  
Long Term Treatment ◽  
Post Infusion ◽  
Control Of Diabetes ◽  
High Level

A relationship between tPA activity and plasmin-mediated fibrinolysis in vivo (plasma levels of Bβ15-42-containing peptides) has been suggested by our previous studies: inverse correlations of Bβ15-42 levels with obesity and triglyceride levels (both associated with high tPA inhibition) in an epidemiological study; and increased levels of Bβ15-42 following improved control of diabetes, or treatment with oral or intramuscular stanozolol (which decrease tPA inhibition). The aim of the present study was to establish whether or not intravenous infusion of desamino-D-arginine vasopressin (DDAVP, desmopressin) is followed by increases in plasmin-mediated fibrinolysis in vivo (plasma Bβ15-42 levels). Desmopressin (0.3 μg/kg body weight) was infused intravenously over 15 mins in 22 subjects. Venous blood was obtained by separate venepuncture before and 15 mins after the end of the infusion, for assay of plasminogen activator activity of the euglobulin fraction on fibrin plates, tPA activity, and Bβ15-42 levels (RIA,IMCO). 18 subjects showed normal increases in fibrin plate lysis and in tPA activity after desmopressin (median tPA activity 120 mU/ml pre-, 5000 mU/ml post-infusion, p<0.001). In these 18 subjects, Bβ15-42 levels rose significantly (median 1.5pmol/ml pre-, 4.2 pmol/ml post-infusion, p<0.001). Four subjects showed no significant increases in fibrin plate lysis or in tPA activity after desmopressin (non-responders): all had significantly elevated levels of tPA-inhibition. In these 4 subjects no increases in Bβ15-42 levels were observed. In one nonresponder, who suffered a large myocardial infarction due to angiographic thrombosis with no atheroma at the age of 22 years, long-term treatment with stanozolol normalised the high level of tPA-inhibition, as well as the fibrin plate lysis and tPA activity responses to desmopressin: Bβ15-42 level then showed a normal response after desmopressin infusion (2.2 to 5 pmol/ml). We conclude that desmopressin infusion increases plasmin-mediated fibrinolysis in vivo, but only in the presence of normal increases in tPA activity.

scholarly journals Mangiferin-Loaded Smart Gels for HSV-1 Treatment

Pharmaceutics ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1323
Author(s):  
Mariaconcetta Sicurella ◽  
Maddalena Sguizzato ◽  
Rita Cortesi ◽  
Nicolas Huang ◽  
Fanny Simelière ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Topical Administration ◽  
Plaque Reduction Assay ◽  
Control Drug ◽  
Human Volunteers ◽  
Cutaneous Administration ◽  
Hsv 1

Infections due to HSV-1 affect many people all over the world. To counteract this pathology, usually characterized by perioral sores or by less frequent serious symptoms including keratitis, synthetic antiviral drugs are employed, such as acyclovir, often resulting in resistant viral strains under long-term use. Many plant-derived compounds, such as mangiferin and quercetin, have demonstrated antiviral potentials. In this study, smart semisolid forms based on phosphatidylcholine and Pluronic were investigated as delivery systems to administer mangiferin on skin and mucosae affected by HSV-1 infection. Particularly, lecithin organogels, Pluronic gel, and Pluronic lecithin organogels were formulated and characterized. After the selection of gel compositions, physical aspects, such as rheological behavior, spreadability, leakage, and adhesion were evaluated, suggesting a scarce suitability of the lecithin organogel for topical administration. Mangiferin was efficiently included in all type of gels. An in vitro study based on the Franz cell enabled us to find evidence of the gel capability to control drug diffusion, especially in the case of Pluronic organogel, while an in vivo study conducted on human volunteers demonstrated the safeness of all of the gels after cutaneous administration. Furthermore, a plaque reduction assay demonstrated the virucidal effect of mangiferin loaded in a Pluronic gel and a Pluronic lecithin organogel against the HSV-1 KOS strain.

Transdermal Delivery of Salmon Calcitonin Using a Dissolving Microneedle Array: Characterization, Stability, and In vivo Pharmacodynamics

2020 ◽  
Vol 22 (1) ◽  
Author(s):  
Lu Zhang ◽  
Yingying Li ◽  
Fang Wei ◽  
Hang Liu ◽  
Yushuai Wang ◽  
...  
Keyword(s):  
Salmon Calcitonin ◽  
Transdermal Delivery ◽  
Microneedle Array

Long term in vivo reactions to PTFE and polyester in the cardiovascular system - what will be the fate of septal defect occlusion devices?

2014 ◽  
Vol 62 (S 01) ◽  
Author(s):  
M. Sigler ◽  
S. Huell ◽  
R. Foth ◽  
W. Ruschewski ◽  
T. Tirilomis ◽  
...  
Keyword(s):  
Cardiovascular System ◽  
Septal Defect

The depressing (negative) effect of oestradiol benzoate on the in vitro secretion of LH and FSH by the pituitary gland of the LRH-pretreated long-term ovariectomized rat changes into the augmentative (positive) effect after discontinuation of the LRH-pretreatment

1985 ◽  
Vol 110 (3) ◽  
pp. 329-337 ◽  
Author(s):  
G. A. Schuiling ◽  
H. Moes ◽  
T. R. Koiter
Keyword(s):  
Depressing Effect ◽  
Ovx Rats ◽  
Gonadotrophin Secretion ◽  
Oestradiol Benzoate ◽  
Negative Effect ◽  
Positive Effect ◽  
Perifusion System

Abstract. The effect of pretreatment in vivo with oestradiol benzoate on in vitro secretion of LH and FSH was studied in long-term ovariectomized (OVX) rats both at the end of a 5-day continuous in vivo pretreatment with LRH and 4-days after cessation of such LRH pretreatment. Rats were on day 0 sc implanted with osmotic minipumps which released LRH at the rate of 250 ng/h. Control rats were implanted with a piece of silicone elastomer with the dimensions of a minipump. On days 2 and 4 the rats were injected with either 3 μg EB or with oil. On day 5 part of the rats were decapitated and the in vitro autonomous (i.e. non-LRH-stimulated) and 'supra-maximally' LRHstimulated release of LH and FSH was studied using a perifusion system. From other rats the minipumps were removed on day 5 and perifusion was performed on day 9. On the 5th day of the in vivo LRH pretreatment the pituitary LH/FSH stores were partially depleted; the pituitaries of the EB-treated rats more so than those of the oil-injected rats. EB alone had no significant effect on the content of the pituitary LH- and FSH stores. On day 9, i.e. 4 days after removal of the minipumps, the pituitary LH and FSH contents had increased in both the oil- and the EB injected rats, but had not yet recovered to control values. In rats not subjected to the 5-days pretreatment with LRH EB had a positive effect on the supra-maximally LRH-stimulated secretion of LH and FSH as well as on the non-stimulated secretion of LH. EB had no effect on the non-stimulated secretion of FSH. After 5 days of in vivo pretreatment with LRH only, the in vitro non-stimulated and supra-maximally LRH-stimulated secretion of both LH and FSH were strongly impaired, the effect correlating well with the LRH-induced depletion of the pituitary LH/FSH stores. In such LRH-pretreated rats EB had on day 5 a negative effect on the (already depressed) LRH-stimulated secretion of LH (not on that of FSH). EB had no effect on the non-stimulated LH/FSH secretion. It could be demonstrated that the negative effect of the combined LRH/EB pretreatment was mainly due to the depressing effect of this treatment on the pituitary LH and FSH stores: the effect of oestradiol on the pituitary LRH-responsiveness (release as related to pituitary gonadotrophin content) remained positive. In LRH-pretreated rats, however, this positive effect of EB was smaller than in rats not pretreated with LRH. Four days after removal of the minipumps there was again a positive effect of EB on the LRH-stimulated secretion of LH and FSH as well as on the non-stimulated secretion of LH. The positive effect of EB on the pituitary LRH-responsiveness was as strong as in rats which had not been exposed to exogenous LRH. The non-stimulated secretion of FSH was again not affected by EB. The results demonstrate that the effect of EB on the oestrogen-sensitive components of gonadotrophin secretion consists of two components: an effect on the pituitary LRH-responsiveness proper, and an effect on the pituitary LH/FSH stores. The magnitude of the effect of EB on the LRH-responsiveness is LRH dependent: it is very weak (almost zero) in LRH-pretreated rats, but strong in rats not exposed to LRH as well as in rats of which the LRH-pretreatment was stopped 4 days previously. Similarly, the effect of EB on the pituitary LH and FSH stores is LRH-dependent: in the absence of LRH, EB has no influence on the contents of these stores, but EB can potentiate the depleting effect of LRH on the LH/FSH-stores. Also this effect disappear after cessation of the LRH-pretreatment.

Enhanced Stability and Controlled Delivery of MOF Encapsulated Vaccines and Their Immunogenic Response In Vivo

2018 ◽  
Author(s):  
Michael Luzuriaga ◽  
Raymond P. Welch ◽  
Madushani Dharmawardana ◽  
Candace Benjamin ◽  
Shaobo Li ◽  
...  
Keyword(s):  
Viral Vector ◽  
Controlled Delivery ◽  
Conformational Structure ◽  
Spectroscopy Analysis ◽  
Zeolitic Imidazolate Framework ◽  
Structural Conformation ◽  
Depth Study ◽  
Viral Nanoparticle

<div><div><div><p>Vaccines have an innate tendency to lose their structural conformation upon environmental and chemical stressors. A loss in conformation reduces the therapeutic ability to prevent the spread of a pathogen. Herein, we report an in-depth study of zeolitic imidazolate framework-8 (ZIF-8) and its ability to provide protection for a model viral vector against dena- turing conditions. The immunoassay and spectroscopy analysis together demonstrate enhanced thermal and chemical stability to the conformational structure of the encapsulated viral nanoparticle. The long-term biological activity of this virus-ZIF composite was investigated in animal models to further elucidate the integrity of the encapsulated virus, the bio-safety, and immunogenicity of the overall composite. Additionally, histological analysis found no observable tissue damage in the skin or vital organs in mice, following multiple subcutaneous administrations. This study shows that ZIF-based protein composites are strong candidates for improved preservation of proteinaceous drugs, are biocompatible, and capable of controlling the release and adsorption of drugs in vivo.</p></div></div></div>

THE ROLE OF POLYETHYLENIMINE IN ENHANCING PERFORMANCE OF GLUTAMATE BIOSENSORS

2018 ◽  
Vol 8 (3) ◽  
pp. 36-41
Author(s):  
Diep Do Thi Hong ◽  
Duong Le Phuoc ◽  
Hoai Nguyen Thi ◽  
Serra Pier Andrea ◽  
Rocchitta Gaia
Keyword(s):  
First Generation ◽  
Good Reproducibility ◽  
Complex Matrices ◽  
Long Term Stability ◽  
In Vitro Characterization ◽  
Glutamate Oxidase

Background: The first biosensor was constructed more than fifty years ago. It was composed of the biorecognition element and transducer. The first-generation enzyme biosensors play important role in monitoring neurotransmitter and determine small quantities of substances in complex matrices of the samples Glutamate is important biochemicals involved in energetic metabolism and neurotransmission. Therefore, biosensors requires the development a new approach exhibiting high sensibility, good reproducibility and longterm stability. The first-generation enzyme biosensors play important role in monitoring neurotransmitter and determine small quantities of substances in complex matrices of the samples. The aims of this work: To find out which concentration of polyethylenimine (PEI) exhibiting the most high sensibility, good reproducibility and long-term stability. Methods: We designed and developed glutamate biosensor using different concentration of PEI ranging from 0% to 5% at Day 1 and Day 8. Results: After Glutamate biosensors in-vitro characterization, several PEI concentrations, ranging from 0.5% to 1% seem to be the best in terms of VMAX, the KM; while PEI content ranging from 0.5% to 1% resulted stable, PEI 1% displayed an excellent stability. Conclusions: In the result, PEI 1% perfomed high sensibility, good stability and blocking interference. Furthermore, we expect to develop and characterize an implantable biosensor capable of detecting glutamate, glucose in vivo. Key words: Glutamate biosensors, PEi (Polyethylenimine) enhances glutamate oxidase, glutamate oxidase biosensors

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