Design and evaluation of dry-coated tablets for colonic delivery of diclofenac sodium

A colonic drug delivery system is required to protect a drug during its transit through the upper gastro-intestinal tract and allow its release in the colon. The aim of this study was the preparation of dry-coated tablets designed for colonic release of the model drug Diclofenac sodium (DS). The system consists of a drug-pectine (PC) mixture as the core and hydroxypropylmethylcellulose (HPMC) alone or mixed in different ratios with poly(ε-caprolactone) (CL) as the coat layer

Removal of acetaldehyde from saliva by mucoadhesive formulations containing cysteine and chlorhexidine diacetate: a possible approach to the prevention of oral cavity alcohol-related cancer

The aim of our work has been to develop buccoadhesive formulations (tablets) containing both L-cysteine and chlorhexidine diacetate and to verify their ability to reduce oral acetaldehyde produced after alcoholic drinks consumption

The molecular characterization of HSVd isolates associated with dapple fruit and fruit rugosity in plum seedlings suggests a possible role of breeding in viroid dissemination

In a wide range of hosts, the infection caused by Hop stunt viroid (HSVd) appears to be latent, whereas in some others it is frequently pathogenic. In this work, the presence of HSVd has been found to be associated with symptoms of dapple fruit and fruit rugosity in plum seedlings obtained from cross breeding for quality. Symptomatic and symptomless plum seedling samples have been analyzed for the presence of the principal stone fruit viroids and viruses. HSVd was found in all symptomatic samples, whereas no other viruses or viroids were found in the analyzed samples with the exception of ACLSV, which was detected rarely. The RNAs of all HSVd isolates have been cloned and sequenced. The sequence analysis showed a high percentage of homology among the isolates, making it possible to hypothesize a potential unique origin of the infection. For this purpose, those plants used in breeding as pollen donors have been analyzed. The results showed that the same HSVd isolate was also present in the parental plants, both in the leaves and pollen, suggesting a possible role of breeding in the dissemination of the viroid.Keywords: Plum, seedlings, fruit rugosity, dapple fruit, HSVd, polle

<i>In vitro</i> and <i>in vivo</i> studies of artichoke extract (<i>Cynara scolymus</i> L.) as ketoprofen skin penetration enhancer

In this study, the enhancing effect of artichoke extract containing cynaropicrin on the in vitro and in vivo percutaneous absorption of ketoprofen from gels has been investigated

Study of dissolution rate enhancement of poorly water soluble drug

Aim of this work is the preparation of spray-dried microspheres as drug delivery systems for Rokitamycin (RK), using chitosan (C) and its salt, chitosan glutamate (CG) to improve the dissolution rate of the drug. The work further aimed to investigate the effect of the type of chitosan and feed solution concentration on the microsphere properties

Identification and characterization of Peach latent mosaic viroid and Hop stunt viroid in different peach cultivars showing dapple fruit, fruit yellow mosaic and cracked suture symptoms

From the early 1990s, a fruit peach syndrome characterized mainly by small discoloured spots (dapple fruit) and/or yellow areas on the skin (yellow mosaic), cracked suture and deformations was identified in most commercial orchards in the Emilia Romagna region (Northern Italy). In the past, Peach latent mosaic viroid (PLMVd) and Hop stunt viroid (HSVd) have been detected in trees with symptomatic fruits. In order to ascertain the presence and spread of these two viroids, symptomatic fruit samples were collected from five different cultivars: ‘Royal Glory’, ‘Crimson Lady’, ‘Grenat’, ‘Diamond Princess’ and ‘Laura’. Dapple fruit symptoms affected all cultivars, ‘Grenat’ samples also showed evident yellow mosaic and fruit deformation, and ‘Royal Glory’ severe cracked sutures. The results showed a large diffusion of the two viroids, mainly in mixed infections. Anvaluation of the role the viroids could play in symptom expression has been complicated by the high number of samples infected by both viroids (60%). Nonetheless, PLMVd was confirmed to be strictly associated with the yellow mosaic, cracked suture and fruit deformation symptoms. The aetiological origin of the dapple fruit disease, however, seems to be more complicated, since in the ‘Diamond Princess’, only PLMVd has been found to be associated with the symptoms, whereas in all other cultivars, the presence of HSVd could have influenced the symptom expression. Moreover, the molecular characterization of some PLMVd isolates does not show any correlation between nucleotide sequence and symptoms although new PLMVd variants were identified. Keywords: peach fruit symptoms, PLMVd, HSVd, mixed infectio

A Calorimetric Study on Diflunisal Release from Poly(Lactide-co-Glycolide) Microspheres by Monitoring the Drug Effect on Dipalmitoylphosphatidylcholine Liposomes: Temperature and Drug Loading Influence

Diflunisal release from poly-Lactide-co-Glycolide (50:50, 34,000 MW) microspheres loaded with two different amounts of drug (2.5 +/- 0.5% and 10 +/- 0.5% w/w) was monitored by following the effects exerted by the drug on the thermotropic behavior of dipalmitoylphosphatidylcholine unilamellar vesicles at different temperatures. The effects of the drug released from the microspheres on the thermotropic behavior of lipid aqueous dispersion containing different molar ratios of drug was detected by differential scanning calorimetry and was compared with the effects exerted by the free Diflunisal. Diflunisal affects mainly the temperature (Tm) of the transition characteristic of phospholipid vesicles as model biomembrane, causing a shift toward lower values. This shift was modulated by the drug molar fraction with respect to the lipid concentration in the aqueous dispersion. Afterward, calorimetric measurements were performed on suspensions of blank liposomes added to weighed amounts of unloaded and differently Diflunisal-loaded microspheres as well as free powdered Diflunisal after incubation for increasing times at three different temperatures (25, 37, and 50 degrees C). The Tm shifts of the lipid bilayer, caused by the drug released from polymeric system as well as by the free drug during incubation periods, were compared with that caused by free drug increasing molar fractions dispersed directly on the membrane, employed as a calibration curve to obtain the fraction of drug released. This in vitro study suggests that the kinetic process involved in drug release is influenced by the amount of drug loaded in the microspheres as well as by the temperature acting on drug solubility and membrane disorder. This drug release model, monitored by the calorimetric technique shows that a) the poly-Lactide-co-Glycolide microspheres are a good delivery system able to sustain the drug release; b) the differential scanning calorimetry technique applied on the drug interaction with biomembranes constitutes a good tool to follow the drug release; 3) this model, representing an innovative alternative in vitro model, should be used to determine the different kinetics involved in the drug transfer from a drug delivery system to a membrane as uptake site

Improving Dermal Delivery of Rose Bengal by Deformable Lipid Nanovesicles for Topical Treatment of Melanoma

Cutaneous melanoma is one of the most aggressive and metastatic forms of skin cancer. However, current therapeutic options present several limitations, and the annual death rate due to melanoma increases every year. Dermal delivery of nanomedicines can effectively eradicate primary melanoma lesions, avoid the metastatic process, and improve survival. Rose Bengal (RB) is a sono-photosensitizer drug with intrinsic cytotoxicity toward melanoma without external stimuli but the biopharmaceutical profile limits its clinical use. Here, we propose deformable lipid nanovesicles, also known as transfersomes (TF), for the targeted dermal delivery of RB to melanoma lesions to eradicate them in the absence of external stimuli. Considering RB's poor ability to cross the stratum corneum and its photosensitizer nature, transfersomal carriers were selected simultaneously to enhance RB penetration to the deepest skin layers and protect RB from undesired photodegradation. RB-loaded TF dispersion (RB-TF), prepared by a modified reverse-phase evaporation method, were nanosized with a ζ-potential value below -30 mV. The spectrophotometric and fluorimetric analysis revealed that RB efficiently interacted with the lipid phase. The morphological investigations (transmission electron microscopy and small-angle X-ray scattering) proved that RB intercalated within the phospholipid bilayer of TF originating unilamellar and deformable vesicles, in contrast to the rigid multilamellar unloaded ones. Such outcomes agree with the results of the in vitro permeation study, where the lack of a burst RB permeation peak for RB-TF, observed instead for the free drug, suggests that a significant amount of RB interacted with lipid nanovesicles. Also, RB-TF proved to protect RB from undesired photodegradation over 24 h of direct light exposure. The ex vivo epidermis permeation study proved that RB-TF significantly increased RB's amount permeating the epidermis compared to the free drug (78.31 vs 38.31%). Finally, the antiproliferative assays on melanoma cells suggested that RB-TF effectively reduced cell growth compared to free RB at the concentrations tested (25 and 50 μM). RB-TF could potentially increase selectivity toward cancer cells. Considering the outcomes of the characterization and cytotoxicity studies performed on RB-TF, we conclude that RB-TF represents a valid potential alternative tool to fight against primary melanoma lesions via dermal delivery in the absence of light

Nanoparticles based on hydroxypropylcyclodextryn: preparation and in vitro viability study on Caco2 cells

The work purpose was to prepare and in vitro characterise solid nanoparticles based on hydroxypropyl-β-cyclodextrin (HP) by high pressure emulsification method; the effect on the viability of the formulations on Caco2 cells has been also evaluated