Flaxseed lignan wound healing formulation: characterization and in vivo therapeutic evaluation.

Flaxseed lignans are a natural source of useful biologically active components that show a diverse spectrum of health-promoting properties. The valuable effects of the phenolic molecules are mainly due to their antioxidant activity by preventing oxidative stress and stimulate collagen synthesis, therefore, providing benefits to the skin. The present work highlights the development of flaxseed extract formulation as novel wound healing agent. The recognition of key structural features within flaxseed extract was crucial for the design and development of the therapeutic cream. Chromatographic analyses were employed for bioactive compounds identification and quantification. Folin-Ciocalteu method determined the total phenolic content and the antioxidant properties were evaluated by DPPH assay. The storage and loss modulus and tan δ were calculated for cream rheological properties evaluation. In vitro diffusion capacity and in vivo wound healing activity of phenolic cream were evaluated on Wistar rats. The collective properties and healing effect of the flaxseed suggested wound healing capacity.

Evaluation of the wound-healing effect of a novel Hypericum perforatum ointment in skin injury.

The present experiment aims to formulate and characterize a new phytotherapy ointment based on a total extract of Hypericum perforatum included in a novel ointment base. In order to investigate the healing properties of the ointment, in vivo experimental wound models of linear incision, circular excision and thermal burn were performed on Wistar rats. Topical treatment was achieved daily, for 21 days. Clinical and macroscopic evaluation, determination of wound contraction rate, period of re-epithelialization, and histopathological examination were achieved, along with the determination of the particle diameter and particle size distribution of the ointment. The results demonstrate that the tested novel ointment has significant wound healing effect in skin injuries and reveals to be safe for use.

In vitro antimicrobial activity of Romanian medicinal plants hydroalcoholic extracts on planktonic and adhered cells.

The aim of this study was to assess the antibacterial and antifungal potential of some Romanian medicinal plants, arnica--Arnica montana, wormwood--Artemisia absinthium and nettle--Urtica dioica. In order to perform this antimicrobial screening, we obtained the vegetal extracts and we tested them on a series of Gram-positive and Gram-negative bacteria, and also against two fungal strains. The vegetal extracts showed antimicrobial activity preferentially directed against the planktonic fungal and bacterial growth, while the effect against biofilm formation and development was demonstrated only against S. aureus and C. albicans. Our in vitro assays indicate that the studied plant extracts are a significant source of natural alternatives to antimicrobial therapy, thus avoiding antibiotic therapy, the use of which has become excessive in recent years.

Enzyme-assisted purification of denatured atelocollagen, using pronase as scavenging agent.

Collagen liquid-crystal characteristics can be exploited in advanced applications, like microelectromechanical systems (MEMS), collagen-silica biohybrids or intelligent substrates for tissue engineering. Such applications necessarily require high purity of the collagen colloidal solutions, in terms of macromolecular unitary composition, which is equivalent to almost zero poydispersity. In this work a protocol for the enzyme-assisted removal of non-triple helical polypeptide entities in atelocollagen solutions was conceived, using pronase as scavenger, in the presence of poly(ethyleneglycol) (PEG 10000) as a crowding agent, trimethylamine-N-oxide dihydrate, (TMAO) as kosmotropic agent and anhydrous sodium sulfate as anti-chaotrope salt. Unusually high enzyme concentration (3 : 100 w/w 5 U/mg Pronase : total dry protein) imposes the triple-helix integrity protection, which was achieved by means of protective adjuvants. The adjuvant agents mixture comprising the crowder, the kosmotrope and the anti-chaotropic salt, was formulated according to the Design of Experiments (DOE) principles. The crowding agent represents the key factor in modulating pronase hydrolytic action upon atelocollagen substrate. The optimal adjuvant mixture tested in order to confirm the model validity had the composition: 0.675 PEG, 0.200 TMAO, 0.125 Na2SO4 (mass fractions). The proposed protocol is suitable for purifying medium and large quantities of atelocollagen previously solubilized through an alkali-enzyme technique.

The occurrence and antimicrobial susceptibility of salmonellae isolated from commercially available canine raw food diets in three Canadian cities.

The purpose of the present study was to evaluate the prevalence and antimicrobial resistance patterns of Salmonella isolated from commercially available canine raw food diets in Canada. A total of 166 commercial frozen raw food diet samples were purchased from randomly selected local pet stores in three Canadian cities for a period of 8 months. All samples were evaluated for the presence of Salmonella, serotyped and tested for antimicrobial susceptibility. There was an overall Salmonella prevalence of 21%; chicken was an ingredient for 67% of the Salmonella-positive diets. Eighteen different Salmonella serotypes were recovered, and resistance was observed to 12 of the 16 antimicrobials tested, with the majority of Ontario isolates exhibiting resistance to ampicillin and Calgary isolates to tetracycline. This study demonstrates the potential risk of raw food diets, especially for immunocompromised individuals, and stresses the need for implementing regulatory guidelines for the production of these diets in order to help control and ideally eliminate the bacterial risks associated with their use and consumption.

The occurrence and anti-microbial susceptibility of Salmonellae isolated from commercially available pig ear pet treats.

In Canada, there have been reported outbreaks of human salmonellosis related to exposure to animal-derived pet treats, involving pig ear treats, beef steak patty dog treats and pet treats of seafood origin. As a follow-up to recommendations made to the pig ear treat industry in 1999, a total of 245 pig ear treats were purchased in two Canadian cities to provide evidence of adoption of the recommendations and to determine the current levels of Salmonella contamination of pig ear treats available at pet stores. An overall prevalence of 4% was observed, with isolates exhibiting resistance to up to seven anti-microbials. Serotypes recovered included S. Bovismorbificans, S. Give, S. Derby and S. Typhimurium var. Copenhagen. Although the prevalence observed during this study is lower than the prevalence observed in 1999, pig ear treats should still be considered as a possible source of Salmonella and anti-microbial resistant bacteria to humans and dogs in Canada.

Influence of food matrix on inactivation of Bacillus cereus by combinations of nisin, pulsed electric field treatment, and carvacrol.

Carvacrol was used as a third preservative factor to enhance further the synergy between nisin and pulsed electric field (PEF) treatment against vegetative cells of Bacillus cereus. When applied simultaneously with nisin (0.04 microg/ml), carvacrol (0.5 mM) enhanced the synergy found between nisin and PEF treatment (16.7 kV/cm, 30 pulses) in potassium-N-2-hydroxyethylpiperazine-N-ethanesulfonic acid (HEPES) buffer. The influence of food ingredients on bactericidal activity was tested using skimmed milk that was diluted to 20% with sterile demineralized water. The efficacy of PEF treatment was not affected by the presence of proteins, and results found in HEPES buffer correlated well with results in milk (20%). Nisin showed less activity against B. cereus in milk. Carvacrol was not able to enhance the synergy between nisin and PEF treatment in milk, unless used in high concentrations (1.2 mM). This concentration in itself did not influence the viable count. Carvacrol did act synergistically with PEF treatment in milk, however not in HEPES buffer. This synergy was not influenced by proteins in milk, as 5% milk still allows synergy between carvacrol and PEF treatment to the same extent as 20% milk.

Thyroid hormone-induced reduction of urinary 5-hydroxyindole acetic acid (5 HIAA) in obese children. Comparison with hypothyroid patients of similar age having either pituitary dwarfism or congenital myxedema.

Urinary excretion of monoamine metabolites (noradrenaline-NA, adrenaline-A, 3-methoxy-4-hydroxyphenyl glycol-MHPG, homovanillic acid-HVA, 5-hydroxyindole acetic acid-5 HIAA) was studied in four groups of children as follows: Group I consisting of obese children subjected to caloric restriction and to a short term course of thyroid extract in "low" dosage (1-2 mg/kg bwt), Group II consisting of obese children subjected to diet alone, Group III consisting of children myxedema and subjected to a short term course of thyroid extract given in the "high" dosage (3-5 mg/kg bwt) and Group IV consisting of GH deficient short children having (many of them) thyrotropin deficiency and subjected to a short term course of thyroid extract in "very high" dosage (5-10 mg/bwt). In obese, calorie-restricted children, the previously low mean level of 5 HIAA excretion was further lowered by thyroid extract. In obese children subjected to calorie restriction alone no urinary abnormality was noted. The congenitally hypothyroid patients had low levels of basal 5 HIAA when compared to controls. The degrees of 5-hydroxy tryptamine (5 HT) deficiency in Group III was similar to the obese groups. The thyroid extract course did not influence, at least in short term administration, the low 5 HIAA levels in group III. In GH deficient, short children (group IV) thyroid extract had no significant effect on urinary pattern of monoamine metabolites. A central 5 HT deficiency may tentatively explain the mood disturbances and possibly the other psychic disorders in both the obese and myxedematous patients. The different effects of thyroid extract on 5 HIAA may also witness the differences in the food intake behaviour in these two conditions.

Mild stimulation of serum immunoreactive insulin (IRI) release following large doses of intravenously given glycine to children of normal pituitary function.

In healthy, sexually immature children of both sexes serum IRI levels rose more than expected from random inter-individual variation (i.e. more than 3 standard deviations of the basal level) in 10 out of 21 subjects loaded by glycine. The IRI release by glycine though moderate and not constant is, however, unquestionable. The growth hormone (GH) secretory response to glycine did not change according to the occurrence and/or magnitude of IRI release. It was concluded that GH and IRI stimulatory properties of glycine given intravenously in large doses are completely unrelated.