PHYSICAL APPROACH TO TRANSDERMAL DRUG DELIVERY: A REVIEW

Transdermal drug delivery system (TDDS) is the topically administered medication, which when applied to the skin, delivers the drug through the skin for systemic effect at a predetermined and controlled rate. For the drugs, having the short biological half-life, transdermal drug delivery system is convenient. It overcomes the problems  like the hepatic first pass effect, improves the compliance of patients, decreases the administration frequency, and reduce the gastrointestinal side effects, peak and valley levels in the blood are avoided. Due to having an advantage of being non-invasive, this delivery has to fulfill some parameters such as high potency, better permeability through skin and non-irritation for better compliance. Skin serves as a site of drug application for local effect as well as systemic effect. There are wide varieties of drugs for which topical or transdermal is a viable option, skin penetration enhancement techniques have been developed for such drugs. There are a number of physical methods to increase drug delivery via the skin, many of which require the use of devices and some of which hold the promise to significantly expand the spectrum of drugs that can be administered transdermally to include water-soluble molecules and macromolecules. Iontophoresis and electroporation represent electrically assisted, physical approaches to enhance delivery of drugs/macromolecules across the stratum corneum.  This review highlights the detailed role of physical penetration and describes their mechanism of action. Keywords: transdermal drug delivery system, stratum corneum, skin penetration enhancer, physical enhancer, iontophoresis.Â

Enrichment of CpG island shore region hypermethylation in epigenetic breast field cancerization

While changes in DNA methylation are known to occur early in breast carcinogenesis and the landscape of breast tumour DNA methylation is profoundly altered compared with normal tissue, there have been limited efforts to identify DNA methylation field cancerization effects in histologically normal breast tissue adjacent to tumour. Matched tumour, histologically normal tissue of the ipsilateral breast (ipsilateral-normal), and histologically normal tissue of the contralateral breast (contralateral-normal) were obtained from nine women undergoing bilateral mastectomy. Laser capture microdissection was used to select epithelial cells from normal tissue, and neoplastic cells from tumour for genome-scale measures of DNA methylation with the Illumina HumanMethylationEPIC array. We identified substantially more CpG loci that were differentially methylated between contralateral-normal and tumour (63,271 CpG loci q \u3c 0.01), than between ipsilateral-normal and tumour (38,346 CpG loci q \u3c 0.01). We identified differential methylation in ipsilateral-normal relative to contralateral-normal tissue (9,562 CpG loci p \u3c 0.01). In this comparison, hypomethylated loci were significantly enriched for breast cancer-relevant transcription factor binding sites including those for ESR1, FoxA1, and GATA3 and hypermethylated loci were significantly enriched for CpG island shore regions. In addition, progression of shore hypermethylation was observed in tumours compared to matched ipsilateral normal tissue, and these alterations tracked to several well-established tumour suppressor genes. Our results indicate an epigenetic field effect in surrounding histologically normal tissue. This work offers an opportunity to focus investigations of early DNA methylation alterations in breast carcinogenesis and potentially develop epigenetic biomarkers of disease risk

Phytosome-conjugated carvacrol: A novel approach for improving growth performance, intestinal morphology and economics of production in Broiler Chicken

Essential oils are plant-derived aromatic volatile oils, and they contain bioactive compounds that have been shown to improve poultry nutrition. However, considering problems associated with the solubility and bioavailability of polyphenolic compounds, the study was planned to find out the effect of the novel feed-grade delivery system, phytosomes for conjugation of plant-derived polyphenolic compound carvacrol on the growth performance of broiler chickens. The experiment was conducted, on 240 broiler chicks for a period of 6 weeks. The chicks were divided into 4 groups having 4 replicates of 15 birds each. The birds in the control group (T0) offered a standard diet as per BIS (2007) specification. Group T1 received a standard diet supplemented with Bacitracin Methylene Disalicylate (BMD) antibiotic at standard dose and group T2 received a standard diet supplemented with carvacrol essential oil @100 mg/kg feed. Group T3 received a standard diet supplemented with phytosome-conjugated carvacrol essential oil (carvacrol @16.6%) @100 mg/kg feed. The performance of all the treatment groups was assessed with respect to the different performance parameters. The supplementation of phytosome-conjugated carvacrol essential oil (carvacrol @16.6%) @ 100 mg/kg feed was found beneficial in terms of growth performance, feed efficiency, and intestinal morphometry. In terms of economics of broiler production, the results revealed that the addition of phytosome- conjugated carvacrol essential oil and carvacrol essential oil in diets was found beneficial in reducing the cost of broiler production, thereby enhancing the margin of profit in broiler production and fetching higher net profit than the control group

The B subunits of cholera and Escherichia coli heat-labile toxins enhance the immune responses in mice orally immunised with a recombinant live P-fimbrial vaccine for avian pathogenic E. coli

This study aimed to investigate the adjuvant effect of recombinant attenuated Salmonella expressing cholera toxin B subunit (CTB) and Escherichia coli heat-labile enterotoxin B subunit (LTB) for the P-fimbriae subunit-based vaccine of avian pathogenic E. coli (APEC) in a murine model. The PapA-specific sIgA and IgG responses were significantly enhanced after immunisation with the Salmonella-PapA vaccine in the presence of CTB or LTB. The group immunised with the Salmonella-LTB strain promoted Th1-type immunity, whereas that immunised with the Salmonella-CTB strain produced Th2-type immunity. We concluded that both Salmonella-CTB and -LTB strains can enhance the immune response to PapA, and that the LTB strain may be a more effective adjuvant for APEC vaccination, which requires higher Th1-type immunity for protection. Thus, our findings provide evidence that immunisation with an adjuvant, LTB, is one of the strategies of developing effective vaccines against P-fimbriated APEC

A Review on Pyrolysis for Sustainable Biomass Conversion

The use of bio-energy is rapidly increasing which is become a crucial significant way to replace fossil fuel. The depletion of fossil fuels is responsible for initiating the utilization of the sustainable energy which has been available surrounding human beings. The employment of such sustainable energy can be possible from waste procreated by living creatures and that is feasible because of thermal decomposition processes, which comprise the gasification, combustion, and pyrolysis process for the production of biochar. The present study portrayed the very promising thermal decomposition process that is the pyrolysis process. The two main pyrolysis processes explained where basic feedstock is biomass invested. This feedstock may have diverse versions as natural live or dead plants, wastage of animals, organic waste, etc. All these feedstocks are responsible for the emission of some amount of carbon which relates to the different modes of operation used in the pyrolysis biomass conversion process. The bioproduct varies due to the effect of various operating conditions such as temperature, heating rate, feedstock, reactors configuration, and reaction time. Demand for bioproducts rising in daily life Due to this circumstance Sustainability of products become prominent while exploited in the proper application such as soil amendment, soil fertility, climate change mitigation, and waste management. This review demonstrates the pyrolysis process to convert simple biomass to sustainable biochar, bio-oil, and syngas with the variation of the amount of product depending on different pyrolysis processes

Construction of a <it>Salmonella</it> Gallinarum ghost as a novel inactivated vaccine candidate and its protective efficacy against fowl typhoid in chickens

Abstract In order to develop a novel, safe and immunogenic fowl typhoid (FT) vaccine candidate, a Salmonella Gallinarum ghost with controlled expression of the bacteriophage PhiX174 lysis gene E was constructed using pMMP99 plasmid in this study. The formation of the Salmonella Gallinarum ghost with tunnel formation and loss of cytoplasmic contents was observed by scanning electron microscopy and transmission electron microscopy. No viable cells were detectable 24 h after the induction of gene E expression by an increase in temperature from 37 °C to 42 °C. The safety and protective efficacy of the Salmonella Gallinarum ghost vaccine was tested in chickens that were divided into four groups: group A (non-immunized control), group B (orally immunized), group C (subcutaneously immunized) and group D (intramuscularly immunized). The birds were immunized at day 7 of age. None of the immunized animals showed any adverse reactions such as abnormal behavior, mortality, or signs of FT such as anorexia, depression, or diarrhea. These birds were subsequently challenged with a virulent Salmonella Gallinarum strain at 3 weeks post-immunization (wpi). Significant protection against the virulent challenge was observed in all immunized groups based on mortality and post-mortem lesions compared to the non-immunized control group. In addition, immunization with the Salmonella Gallinarum ghosts induced significantly high systemic IgG response in all immunized groups. Among the groups, orally-vaccinated group B showed significantly higher levels of secreted IgA. A potent antigen-specific lymphocyte activation response along with significantly increased percentages of CD4+ and CD8+ T lymphocytes found in all immunized groups clearly indicate the induction of cellular immune responses. Overall, these findings suggest that the newly constructed Salmonella Gallinarum ghost appears to be a safe, highly immunogenic, and efficient non-living bacterial vaccine candidate that protects against FT.</p

Wideband, polarization independent electromagnetic wave absorber using cross arrow resonator and lumped SMD resistors for C and X band applications

In this work, a polarization independent and wideband electromagnetic (EM) waves absorbing frequency selective surface (FSS) structure is presented. The unit cell of the proposed FSS consists of an assembly of cross arrow resonators with four SMD resistors mounted on it, to enhance the absorbance bandwidth. This unit cell also possesses a four-fold symmetry which makes it polarization insensitive. The designed unit cell is compact with the length and width dimensions as 0.19λL × 0.19λL, and thickness of 0.13λL, where λL is the guided wavelength corresponding to the lowest operating frequency. The proposed absorber is theoretically and experimentally tested for its absorbance, cross-polarization level, and radar cross section (RCS) characteristics. The computer-aided simulation and practical measurements indicate that the proposed absorber offers more than 90% (with a fractional bandwidth of 93%) absorbance for normal incidence at 4.5–12.4 GHz frequency band. The cross-polarization reflection coefficient analysis indicates that the proposed FSS configuration behaves as an absorber and not a polarization convertor. The input impedance plot, surface current distribution, and E-field distribution of the unit cell were also analyzed and presented to understand the absorbance mechanism. The RCS of the proposed FSS is compared with the RCS of a reflective (metallic) sheet to analyze its suitability for practical applications (RCS reduction) within the working band. The 3D simulated and 2D calculated RCS results indicate that the proposed FSS is suitable for wideband EM wave absorber applications