Transdermal iontophoretic delivery of timolol maleate

Transdermal iontophoresis would be a promising method for the systemic delivery of water soluble and ionic drugs of relatively high molecular size, including peptides. The objective of the present study was to investigate the effect of biological variable such as guinea pig and human cadaver skin and other variables like drug concentration, current density on the transdermal iontophoretic transport of timolol maleate. The permeation profile of drug using solution and gel formulation was studied and compared. For better bioavailability, better patient compliance, and enhanced delivery, an iontophoretic drug delivery system of a timolol maleate matrix gel was formulated using Carbopol 974P. The study was conducted using silver-silver chloride electrodes across the guinea pig and human cadaver skin. Viscosity measurements and flux calculations indicated the suitability of the Carbopol 974P gel for transdermal iontophoretic delivery of timolol maleate. Anodal iontophoresis with silver-silver chloride electrode significantly increased the timolol maleate skin permeation as compared with the passive permeation study. The amount of timolol maleate transported during iontophoresis was significantly different among the different skins. However, iontophoretic gel formulations provided required flux of drug through human cadaver skin.A iontoforese transdérmica seria um método promissor para a liberação sistêmica de fármacos solúveis em água e iônicos de relativamente elevado tamanho molecular, incluindo peptídeos. O objetivo do presente estudo foi investigar o efeito da variável biológica, tais como cobaia e pele de cadáver humano, e outras variáveis como concentração do fármaco, densidade de corrente sobre o transporte transdérmico iontoforético de maleato de timolol. Comparou-se o perfil de permeação do fármaco usando a formulação de solução e de gel. Para melhor biodisponibilidade, melhor adesão do paciente e liberação aprimorada, formulou-se sistema de liberação iontoforética gel de maleato de timolol usando Carbopol 974P. O estudo foi conduzido usando eletrodos de prata-cloreto de prata na cobaia e na pele de cadáver humano. Medidas de viscosidade e de fluxo indicaram a adequação do gel Carbopol 974 P para liberação iontoforética transdérmica do maleato de timolol. A iontoforese anódica com eletrodo de prata-cloreto de prata aumentou significativamente a permeação dérmica do maleato de timolol, comparativamente à permeação passiva. A quantidade de maleato de timolol transportado durante a iontoforese foi significativamente diferente entre as diferentes peles . No entanto, as formulações iontoforéticas de gel forneceram o fluxo necessário do fármaco através da pele de cadáver humano

Synchronization in a network of model neurons

We study the spatiotemporal dynamics of a network of coupled chaotic maps modelling neuronal activity, under variation of coupling strength ε and degree of randomness in coupling p. We find that at high coupling strengths (ε > εfixed) the unstable saddle point solution of the local chaotic maps gets stabilized. The range of coupling where this spatiotemporal fixed point gains stability is unchanged in the presence of randomness in the connections, namely εfixed is invariant under changes in p. As coupling gets weaker (ε < εfixed), the spatiotemporal fixed point loses stability, and one obtains chaos. In this regime, when the coupling connections are completely regular (p=0), the network becomes spatiotemporally chaotic. Interestingly however, in the presence of random links (p > 0) one obtains spatial synchronization in the network. We find that this range of synchronized chaos increases exponentially with the fraction of random links in the network. Further, in the space of fixed coupling strengths, the synchronization transition occurs at a finite value of p, a scenario quite distinct from the many examples of synchronization transitions at p→0. Further we show that the synchronization here is robust in the presence of parametric noise, namely in a network of nonidentical neuronal maps. Finally we check the generality of our observations in networks of neurons displaying both spiking and bursting dynamics

Sonochemical Formation of Peracetic Acid in Batch Reactor: Process Intensification and Kinetic Study

The present chapter highlights the kinetic studies for the sonochemical synthesis of peracetic acid (PAA) in a batch reactor. The effect of different operating parameters including acetic acid to hydrogen peroxide molar ratio, temperature, catalyst loading, effect of ultrasound, were studied using Amberlite IR-120H as a catalyst. The deactivation of the Amberlite IR-120H catalyst has also been studied. The experimental data were further utilized for the estimation of intrinsic reaction rate constants and equilibrium constants. From the experimental results; the optimized PAA concentration was observed for 471 mg/cm3 catalyst loading at 40°C with acetic acid to hydrogen peroxide molar ratio equals to 1:1 in the presence of ultrasound. Results also revealed that the reaction rate was found to be significantly enhanced in the presence of ultrasound, which can be attributed to the enhanced mixing and in-situ formation of H2O2. The use of ultrasound drastically reduces the overall reaction time to 60 min, which is very less compared to 30 h as reported for conventional batch reactor utilizing H2O2 only

Development and In vitro Evaluation of Betahistine Adhesive-Type Transdermal Delivery System

Purpose: To develop a transdermal betahistine (BTH) delivery system using different pressure sensitive adhesives (PSAs) including acrylics, polyisobutylene and styrenic rubber solution.Methods: Formulations were prepared by solvent casting and adhesive transfer method. PSAs - acrylate vinylacetate (AVA), hydrophilic acrylate (HA), acrylic non-curing (ANC), polyisobutylene (PIB), and tackified styrenic rubber solution (TSR) - were evaluated for their suitability in terms of miscibility, maximum drug loading, effect on tack property and in vitro permeation through excised guinea pig skin. Furthermore, one of the PSAs was tested in relation to effect of penetration enhancers on tack property, in vitro permeation, in vivo patch adhesion performance and stability.Results: Only formulations prepared with AVA and HA were stable. Increased drug loading in these PSAs significantly reduced tack. In vitro permeation data across guinea pig skin demonstrated that BTH flux from from the formulation containing HA (F1) was significantly (p < 0.001) higher than that containing AVA (F2). Formulations containing 2 % enhancer showed good tack. Specifically, the formulation containing 2 % oleic acid as enhancer not only showed the highest permeation but also good tack property, non-irritancy for up to 36 h and stability under accelerated conditions.Conclusion: The formulation containing HA as the PSA and 2 % oleic acid as enhancer demonstrated a good potential for further development to an adhesive-type transdermal delivery system for BTH.Keywords: Meniere’s syndrome, Transdermal delivery, Betahistine, Pressure-sensitive adhesives, Penetration enhancersTropical Journal of Pharmaceutical Research December 2010; 9 (6): 516-52

A hairy-root transformation protocol for Trigonella foenum-graecum L. as a tool for metabolic engineering and specialised metabolite pathway elucidation

The development of genetic transformation methods is critical for enabling the thorough characterization of an organism and is a key step in exploiting any species as a platform for synthetic biology and metabolic engineering approaches. In this work we describe the development of an Agrobacterium rhizogenes-mediated hairy root transformation protocol for the crop and medicinal legume fenugreek (Trigonella foenum-graecum). Fenugreek has a rich and diverse content in bioactive specialised metabolites, notably diosgenin, which is a common precursor for synthetic human hormone production. This makes fenugreek a prime target for identification and engineering of specific biosynthetic pathways for the production of triterpene and steroidal saponins, phenolics, and galactomanans. Through this transformation protocol, we identified a suitable promoter for robust transgene expression in fenugreek. Finally, we establish the proof of principle for the utility of the fenugreek system for metabolic engineering programs, by heterologous expression of known triterpene saponin biosynthesis regulators from the related legume Medicago truncatula in fenugreek hairy roots

GAME9 regulates the biosynthesis of steroidal alkaloids and upstream isoprenoids in the plant mevalonate pathway

Steroidal glycoalkaloids (SGAs) are cholesterol-derived molecules produced by solanaceous species. They contribute to pathogen defence but are toxic to humans and considered as anti-nutritional compounds. Here we show that GLYCOALKALOID METABOLISM 9 (GAME9), an APETALA2/Ethylene Response Factor, related to regulators of alkaloid production in tobacco and Catharanthus roseus, controls SGA biosynthesis. GAME9 knockdown and overexpression in tomato and potato alters expression of SGAs and upstream mevalonate pathway genes including the cholesterol biosynthesis gene STEROL SIDE CHAIN REDUCTASE 2 (SSR2). Levels of SGAs, C24-alkylsterols and the upstream mevalonate and cholesterol pathways intermediates are modified in these plants. Delta(7)-STEROL-C5(6)-DESATURASE (C5-SD) in the hitherto unresolved cholesterol pathway is a direct target of GAME9. Transactivation and promoter-binding assays show that GAME9 exerts its activity either directly or cooperatively with the SlMYC2 transcription factor as in the case of the C5-SD gene promoter. Our findings provide insight into the regulation of SGA biosynthesis and means for manipulating these metabolites in crops

THE COVID-19 Pandemic's Impact on Academic Practices and Learning Quality in Higher Education

The inclusion of several new models and methods had been taken into consideration by the educational institutes and organisations to battle the negative impact of the COVID-19 pandemic across the educational paradigm. The study looked into the research questions and the research objectives which were based on the core topic of the study. With the help of the section of the literature review, the examination of the past research was looked into. The provision of the themes and concepts was done through the integration of data from secondary sources and the qualitative research method was implemented. The future scope of the study and the limitations of the respective assignment was also jotted down

Customers' Attitude Towards Digital Advertising Communication

This article aims to investigate how consumers feel about digital marketing messages before making a purchase. 198 respondents to the research solely utilised conventional lines of communication and refrained from using digital channels while making purchases. The essay outlines the benefits of not communicating digitally. Additionally, the research uses cluster analysis to identify the client categories that use conventional communication methods

Approaches and Technologies for Preservation of Sugarcane juice: A Review

Every region of India has access to the cooling sweet soft drink known as sugarcane juice. It is &nbsp;an essential product on the world market since it has great health advantages. Sugarcane juice &nbsp;competes with other soft drinks in the market pushed by health-conscious consumers, and the sugarcane growers profit financially. To extend the shelf life of sugarcane juice, processing must be combined with the development of appropriate preservation methods. Researchers have looked into a variety of sugarcane juice preservation techniques, including chemical, thermal, and non-thermal techniques. Pasteurization is one of the many methods that are used &nbsp;for preserving sugarcane juice. Pasteurization, however, results in the loss of flavor, aroma, colour, taste, and vital nutrients. Non-thermal procedures, which can preserve the nutritional and sensory qualities of fresh juices, are now receiving more attention. This review article examines numerous preservation methods for sugarcane juice, analyses them, and suggests a course of action to assist determine the best method for doing so. Different criteria for different &nbsp;types of technologies are discussed with their advantages and drawbacks. Technologies which &nbsp;do not use chemical additives have also been discussed, while taking their industrial scalability and economical aspects under consideration. Prime focus is kept on developing a technology which is economical, industrially acceptable and greener for the environment

Dynamic Phase Transition from Localized to Spatiotemporal Chaos in Coupled Circle Map with Feedback

We investigate coupled circle maps in presence of feedback and explore various dynamical phases observed in this system of coupled high dimensional maps. We observe an interesting transition from localized chaos to spatiotemporal chaos. We study this transition as a dynamic phase transition. We observe that persistence acts as an excellent quantifier to describe this transition. Taking the location of the fixed point of circle map (which does not change with feedback) as a reference point, we compute number of sites which have been greater than (less than) the fixed point till time t. Though local dynamics is high-dimensional in this case this definition of persistence which tracks a single variable is an excellent quantifier for this transition. In most cases, we also obtain a well defined persistence exponent at the critical point and observe conventional scaling as seen in second order phase transitions. This indicates that persistence could work as good order parameter for transitions from fully or partially arrested phase. We also give an explanation of gaps in eigenvalue spectrum of the Jacobian of localized state