Vesicular systems for delivering conventional small organic molecules and larger macromolecules to and through human skin

The history of using vesicular systems for drug delivery to and through skin started nearly three decades ago with a study utilizing phospholipid liposomes to improve skin deposition and reduce systemic effects of triamcinolone acetonide. Subsequently, many researchers evaluated liposomes with respect to skin delivery, with the majority of them recording localized effects and relatively few studies showing transdermal delivery effects. Shortly after this, Transfersomes were developed with claims about their ability to deliver their payload into and through the skin with efficiencies similar to subcutaneous administration. Since these vesicles are ultradeformable, they were thought to penetrate intact skin deep enough to reach the systemic circulation. Their mechanisms of action remain controversial with diverse processes being reported. Parallel to this development, other classes of vesicles were produced with ethanol being included into the vesicles to provide flexibility (as in ethosomes) and vesicles were constructed from surfactants and cholesterol (as in niosomes). Thee ultradeformable vesicles showed variable efficiency in delivering low molecular weight and macromolecular drugs. This article will critically evaluate vesicular systems for dermal and transdermal delivery of drugs considering both their efficacy and potential mechanisms of action

Evaluation of non-viable biomass of Laurencia papillosa for decolorization of dye waste water

The uptake of fast orange dye by the red seaweed Laurencia papillosa has been demonstrated in order to explore its potential use as low-cost adsorbent. The adsorption kinetics of fast orange dye on the alga with respect to initial dye concentration, contact time, particle size and pH were investigated. The dye removal percentage increased from 25.92 to 67.08% and the equilibrium states were attained at almost 60 min within the experimental concentration range. The adsorption kinetic was analyzed using pseudo-first-order and pseudo-second-order models. The pseudo-second-order model was more appropriate to describe the sorption kinetics based on the relatively high values of the linear squared regression correlation coefficient. The nature of the possible adsorbent and fast orange interactions was examined by the Fourier transform infrared technique. This technique confirmed that hydroxyl, carboxyl, amine, sulfonyl, carbonyl and alkyl groups are responsible for the dye binding process. Significant increase in dye adsorption was observed with the decrease in sorbent particle size coupled with its large surface area. Maximum removal efficiency was determined to be 65.7% at a solution pH of 5. However, Laurencia papillosa proved to be a promising material for removing fast orange dye from aqueous solutions.Keywords: Dye adsorption, Macroalga, Laurencia papillosa, kineticsAfrican Journal of Biotechnology Vol. 12(17), pp. 2215-222

INTESTINAL ABSORPTION OF EPROSARTAN MESYLATE FROM SELF EMULSIFYING SYSTEM AND CYCLODEXTRIN COMPLEX

Objective: The aim of this work was to determine the intestinal membrane transport parameters of eprosartan mesylate (EM) and to investigate self-nano emulsifying drug delivery systems (SNEDDS) and inclusion complexation with hydroxypropyl b cyclodextrin (HPbCD) for enhanced intestinal absorption of eprosartan mesylate. Methods: The intestinal absorption was monitored using the in situ rabbit intestinal perfusion technique. SNEDDS was developed using labrafil, Lauroglycol with a tween in the presence of ethanol. Inclusion complexation was achieved by construction of phase solubility diagram in the presence of HPbCD. The prepared complex was evaluated using Fourier Transform Infrared Spectroscopy (FTIR) and differential scanning calorimetry (DSC). Results: The drug was found to be poorly absorbed from the jejuno-ileum and the colon with the absorption being mainly through paracellular pathway. An inclusion complex was developed between the drug and HPβCD. Perfusion of the drug in the nanoemulsion formulation or as an inclusion complex resulted in a significant increase in the intestinal absorption of the drug compared with the control.Conclusion: SNEDDS and inclusion complexation are promising strategies for enhanced intestinal absorption of eprosartan mesylate

Hot climate effects and their amelioration on some productive and reproductive traits in rabbit does

[EN] This study aimed to improve productive and reproductive performance of female rabbit does during the summer season hot climate using vitamin C or cooled water in combination with equine chorionic gonadotropin (eCG) treatment. Sixty New Zealand White rabbit does were assigned to three groups, according to drinking-water treatment: 1) fresh tap water without any supplementation (control, C), 2) cooled drinking water (10-15ºC) (CW), and 3) fresh tap water supplemented daily with added ascorbic acid (1 g/L) (vitamin C). Twenty four hours before mating, does of each group were randomly divided into two subgroups; H does were intravenously injected with 40 IU/doe eCG, while NH does did not receive any hormonal treatment. Productive and reproductive performance were signifi cantly (P<0.05) improved in the treated groups. Kit weights at kindling and weaning were greater (P<0.05) in both vitamin C and cooled water groups than in the control regardless of hormonal treatment. It is worthy noticed that conception rate and litter size at birth were adversely affected by eCG, especially in does drinking vitamin C. The percentage of mature oocytes was lower (P<0.01) in control than in treated groups. The oocyte maturation rate improved after treatment with vitamin C to reach 80% compared to 66% in control group. In conclusion, cool drinking water or vitamin C is recommended for alleviating heat stress during summer in rabbits.Yassein, S.; Mahmoud, KM.; Maghraby, N.; Ezzo, O. (2008). Hot climate effects and their amelioration on some productive and reproductive traits in rabbit does. World Rabbit Science. 16(3). doi:10.4995/wrs.2008.62616

Different methods of termination of second trimester pregnancy at Women′s Health Hospital, Assiut University: efficacy and complications

Background: Termination of pregnancy in second trimester is one of the greatest challenges in modern obstetrics practice and is more risky than during first trimester. Now the main concern of the obstetrician is to provide the most effective, safest, and cost-effective regimen with least or no complications. Describe the different indications, technique and complications of different methods of TOP used at Women’s Health Hospital, Assiut University.  Identify gap between current practice and guidelines and setting recommendations for filling gap to improve outcomeMethods: Studying the different methods used for all cases with gestational age 13-24 weeks attending at Women′s Health Hospital, Assiut University from the 1st July 2015 to the 1st June 2016, for second trimester termination of pregnancy who are eligible for termination of pregnancy, with exclusion criteria including any case with scared uterus, multiple pregnancy and rupture of membranes.Results: Of the 146 patients, 55 patients received misoprostol alone, 13 cases used foley’s catheter alone, 67 cases received misoprostol in combination with foley’s catheter and hysterotomy done in 9 patients (4 after failed induction and the rest as primary procedure). In present work the most common complication recorded was retained placental parts, 39 patients (26,5%) followed by surgical evacuation. Uterine perforation occurred accidentally in 3 cases during evacuation followed by laparotomy and repair of perforation without hysterectomy. Infection recorded in 3 cases (1.7%). Sever haemorhage occurred in 4 cases where they needed hysterotomy.Conclusions: All methods used in the department showed efficacy. Misoprostol induction was associated with a shorter induction-abortion interval but was associated with higher risk of retained placenta. Foley's catheter induction was more prolonged but it was associated with almost no complication. The most common complication was retained placenta except those who used Foley's catheter as they had no retained placental parts

Penetration enhancers in proniosomes as a new strategy for enhanced transdermal drug delivery

AbstractThe aim of this work is to investigate penetration enhancers in proniosomes as a transdermal delivery system for nisoldipine. This was performed with the goal of optimising the composition of proniosomes as transdermal drug delivery systems. Plain proniosomes comprising sorbitan monostearate, cholesterol, ethanol and a small quantity of water were initially prepared. Subsequently, proniosomes containing lecithin or skin penetration enhancers were prepared and evaluated for transdermal delivery of nisoldipine. The plain proniosomes significantly enhanced the transdermal flux of nisoldipine to reach 12.18μgcm−2h−1 compared with a saturated aqueous drug solution which delivered the drug at a rate of 0.46μgcm−2h−1. Incorporation of lecithin into such proniosomes increased the drug flux to reach a value of 28.51μgcm−2h−1. This increase can be attributed to the penetration enhancing effect of lecithin fatty acid components. Replacing lecithin oleic acid (OA) produced proniosomes of comparable efficacy to the lecithin containing system. The transdermal drug flux increased further after incorporation of propylene glycol into the OA based proniosomes. Similarly, incorporation of isopropyl myristate into plain proniosomes increased drug flux. The study introduced enhanced proniosomes as a promising transdermal delivery carrier and highlighted the role of penetration enhancing mechanisms in enhanced proniosomal skin delivery. The study opened the way for another line of optimisation of niosome proconcentrates

ENHANCEMENT OF DISSOLUTION RATE OF HYDROCHLOROTHIAZIDE

Objective: The aim of this study was to enhance the dissolution rate of hydrochlorothiazide (HCTZ).Methods: Binary solid dispersions (SDs) of HCTZ with increasing weight ratios of poloxamer 407, polyethylene glycol 6000 (PEG 6000) or gelucire 50/13 were prepared by solvent evaporation technique. The solid dispersions were deposited on the surface of aerosil 200 to produce a dry product with large surface area. The SDs were characterized with respect to drug dissolution. The mechanism of dissolution enhancement was researched using Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC).Results: The unprocessed drug showed erratic, slow dissolution which can be explained on the basis of its hydrophobic nature. Preparation of SDs with hydrophilic carriers resulted in a significant increase in the dissolution rate with most of the drug being liberated in the first 5 min. The dissolution pattern of the drug from the prepared SDs depends mainly on the type of polymer used, and the best dissolution pattern was observed in the SD prepared using 1:1 ratio of the drug to gelucire 50/13 in the presence of aerosil 200 as a carrier. FTIR studies revealed no interaction between the drug and polymers. DSC showed a change in the crystalline structure of the drug after SDs formation. This change can explain the recorded dissolution enhancement.Conclusion: The study presented a system capable of increasing the dissolution rate of HCTZ using polymers which can increase the intestinal permeability as well.Keywords: Hydrochlorothiazide, Poloxamer 407, PEG 6000, Gelucire 50/13, Solid dispersion, Dissolutio

Effect of water-in-oil microemulsions and lamellar liquid crystalline systems on the precorneal tear film of albino New Zealand rabbits

The aim of this study is to investigate the effect of phase transition water-in-oil (w/o) microemulsions (ME) and liquid crystalline systems (LC) on the precorneal tear film (PCTF). The study used six albino NZ rabbits and monitored the integrity and stability of the PCTF before and after instillation of test formulations. The effects were evaluated by assessment of the PCTF lipid layer using interferometry, tear evaporation rate measurements, and indirect estimation of tear volume. Ocular application of test formulations changed the appearance of the PCTF lipid layer, indicating lipid layer disruption. The recovery time was longer in case of ME compared with an aqueous solution (SOL). The tear evaporation rate was increased after application of both ME and LC systems compared with the SOL, with the LC system showing the greatest effect. Tear volume measurement results revealed minimal changes associated with the instillation of both ME systems. Whilst phase transition w/o ME systems can interact with the PCTF lipid layer in albino New Zealand rabbits, their effect on the volume of resident tears was found to be minimal