1,720,956 research outputs found
Delivery of a Small Hydrophobic and Large Hydrophilic Molecule via Intranasal Route
No full textThe intranasal route of drug administration is widely known to be a non-invasive route that has the potential to carry a drug directly to the central nervous system (CNS). Drugs with low solubility and large molecular weight are two common problems encountered which interfere with the delivery of potent drugs to a target. The purpose of this project was the preparation, characterization, in vitro and in vivo testing by intranasal administration to hamsters for various formulations of a hydrophobic small molecular weight drug- dibenzoylmethane (DBM) and a hydrophilic large molecular weight drug- oxytocin to study their bioavailability following inhalation into the nasal cavity (NC). The goal is to improve the delivery of drugs to the brain.
The poorly soluble drug, DBM was formulated in brain homogenate (BH), in HPMC polymer suspension and as drug-loaded nanoparticles and characterized in solid and suspension states. DBM was loaded into a novel lipid- and cyclodextrin-based nanoparticle formulation and characterized by various methods. In addition, oxytocin was formulated in BH and in normal saline. In vitro cell culture-based studies, histological characterizations of nasal cavities for glial fibrillary acidic protein (GFAP) protein and in vivo biodistribution studies after intranasal administration were carried out.
DBM loaded nanoparticles were observed to be thermostable and amorphous in nature. The final particle size for the DBM loaded nanoparticles was 163.8±3.2nm. The entrapment efficiency and percentage drug loading of DBM-loaded nanoparticles was 86.4±0.6% and 9.20% respectively. Invitro release studies showed about 95.80% of drug was released from the nanoparticles within 8 days. Oxytocin formulations were characterized by visual evaluations, pH, viscosity and stability. Invivo biodistribution studies after intranasal administration of oxytocin showed presence of 1.7445 ± 0.5714 and 1.895.2 ± 0.4626 ng/mL of oxytocin in the blood after 30 minutes of administration. No drug was detected in blood samples of animals treated with DBM in BH. However, about 40.77171 ± 4.9340 and 44.44912 ± 5.3666 ng/mL of DBM was detected in blood samples of animals administered DBM in HPMC polymer suspension and DBM nanoparticles respectively. Histological studies on the NC confirmed the presence of inoculum within the cavity of lymphatic vessels for both drugs.
Thus, formulations of hydrophobic small molecular weight drug- DBM and a hydrophilic large molecular weight drug- oxytocin were successfully designed and characterized. These were inhaled intranasally by hamsters to determine relative effectiveness and biodistribution.ProQuest Traditional Publishing Optio
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Formulation and Enhancement Strategies for Decontamination and Drug Delivery Into Healthy and Diseased Skin
No full text2022Despite the significant benefits of the oral and intravenous route of drug administration, there are many problems, such as first-pass metabolism and invasiveness, ultimately leading to poor patient adherence. In the past few decades, it has been established that transdermal drug delivery provides many advantages compared to other drug administration routes. The transdermal route allows drug substances to reach the systemic circulation directly across the skin barrier, thereby increasing bioavailability and patient compliance. Developing transdermal delivery systems that fit into the routine and lifestyle of end-users is critical to the success of a biomedical intervention.
Topical and transdermal drug delivery has been studied extensively, mainly on intact/healthy skin. But it is equally relevant to evaluate the enhancement or retardation of these molecules into and across damaged skin. In vitro investigation of healthy and diseased human skin would provide a better understanding of the effect of diseases on drug permeation or retention. Hence, our research focused on studying the extent of absorption and retention of methotrexate into and across healthy as well as diseased human skin. We also screened physical enhancement techniques such as microneedle and iontophoresis to enhance methotrexate delivery into and across the skin.
Other aims of our research focused on screening chemical enhancement techniques to evaluate the enhancement in the delivery of olanzapine and raloxifene across the skin. We used chemical enhancers such as oleic acid, oleyl alcohol, and isopropyl myristate that can disrupt the lipid packing of skin and increase the drug partitioning into and delivery across the skin. Based on these findings, we formulated different transdermal delivery systems for the sustained delivery of olanzapine and raloxifene according to their different physicochemical properties, dosage regimen, and as feasible for their indications.
Our last aim focused on chemical warfare agents that are toxic blister-causing agents developed a century ago that continues to be a potential threat to public health. Our strategy was to develop a foam-based formulation loaded with antidotes that can rapidly and effectively decontaminate the chemical warfare agent from skin. This can be a promising strategy to attenuate cutaneous damage and thereby treat lewisite toxicity.Banga, Ajay K.D'Souza, Martin J.Uddin, Mohammad N.Chougule, MahavirBakshi, PoojaD.Phil
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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