Peptide mimetics of immunoglobulin A (IgA) and FcαRI block IgA-induced human neutrophil activation and migration.

The cross-linking of the IgA Fc receptor (FcαRI) by IgA induces release of the chemoattractant LTB4, thereby recruiting neutrophils in a positive feedback loop. IgA autoantibodies of patients with autoimmune blistering skin diseases therefore induce massive recruitment of neutrophils, resulting in severe tissue damage. To interfere with neutrophil mobilization and reduce disease morbidity, we developed a panel of specific peptides mimicking either IgA or FcαRI sequences. CLIPS technology was used to stabilize three-dimensional structures and to increase peptides' half-life. IgA and FcαRI peptides reduced phagocytosis of IgA-coated beads, as well as IgA-induced ROS production and neutrophil migration in in vitro and ex vivo (human skin) experiments. Since topical application would be the preferential route of administration, Cetomacrogol cream containing an IgA CLIPS peptide was developed. In the presence of a skin permeation enhancer, peptides in this cream were shown to penetrate the skin, while not diffusing systemically. Finally, epitope mapping was used to discover sequences important for binding between IgA and FcαRI. In conclusion, a cream containing IgA or FcαRI peptide mimetics, which block IgA-induced neutrophil activation and migration in the skin may have therapeutic potential for patients with IgA-mediated blistering skin diseases.

Lipid nanocapsules containing the non-ionic surfactant Solutol HS15 inhibit the transport of calcium through hyperforin-activated channels in neuronal cells.

Hyperforin is described as a natural antidepressant inhibiting the reuptake of neurotransmitters and also activating cation channels. However the blood-brain barrier limits the access to the brain of this biomolecule. To circumvent this problem it was envisaged to encapsulate hyperforin into biomimetic lipid nano-carriers like lipid nanocapsules (LNCs). When testing the safety of 25 nm LNCs it appeared that they strongly blocked hyperforin-activated Ca2+ channels of cultured cortical neurons. This inhibition was due to one of their main component: solutol HS15 (polyoxyethylene-660-12-hydroxy stearate), a non-ionic soluble surfactant. Solutol HS15 rapidly depresses in a concentration-dependent manner the entry of Ca2+ through hyperforin-activated channels without influencing store-operated channels. This effect is mimicked by Brij58 but not by PEG600, indicating that the lipid chain of Solutol HS15 is important in determining its effects on the channels. The inhibition of the Ca2+ fluxes depends on the cellular cholesterol content; it is stronger after depleting cholesterol with methyl-ß-cyclodextrin and is nearly absent on cells cultured in a cholesterol-rich medium. When chronically applied for 24 h, Solutol HS15 slightly up-regulates the entry of Ca2+ through hyperforin-activated channels. Similar observations were made when testing 25 nm lipid nanocapsules containing the surfactant Solutol HS15. Altogether, this study shows that Solutol HS15 perturbs in a cholesterol-dependent manner the activity of some neuronal channels. This is the first demonstration that LNCs containing this surfactant can influence cellular calcium signaling in the brain, a finding that can have important clinical implications.

Design and Characterization of Silicone and Surfactant Based Systems for Topical Drug Delivery.

Nanotechnology offers advantages for new drug delivery design by providing drug targeting while minimizing the side effects. Polyoxyethylene 20 cetyl alcohol (CETETH-20) is a surfactant that may form nanostructured systems, such as liquid crystals, when in contact with water/oil, which are structurally similar to biological membranes and may improve skin interaction. The aim of this study was to develop and characterize CETETH 20-based nanostructured systems by combining CETETH-20 with water and different oily phases, including PEG-12-dimethicone for topical drug administration. The systems were characterized by polarized light microscopy (PLM), small-angle X-ray scattering (SAXS), rheology, texture profile analyses (TPA), in vitro cytotoxicity and histopathological analyses of rabbits' skin. Lamellar, hexagonal and cubic phases were identified and their viscoelastic moduli varied according to each phase. The stiffness of the cubic phase was 3-fold higher and twice more adhesive than the hexagonal phase. The formulations did not affect the normal macrophages cells, neither promoted skin irritation. They were spontaneously obtained by simply mixing the components, which corroborates for an ease scaled-up. These results suggest that systems composed of CETETH 20, PEG-12-dimethicone and water are a promising new approach for designing nanostructured topical drug delivery systems.

Efeitos do PEG 3350 e de uma solução enteral, associados ou não ao Ringer lactato, e do NaCl 0,9 por cento sobre a glicose, o lactato, o cortisol e a insulina de equinos hígidos / Effects of PEG 3350 or an enteral solution associated or not with Ringer lactate, and of NaCl 0.9 percent on the glucose, lactate, cortisol and insulin of healthy equines

Este estudo objetivou avaliar e comparar a glicose e o lactato plasmáticos, bem como a insulina e o cortisol séricos, em éguas hígidas, não gestantes, tratadas com: polietilenoglicol 3350 (PEG); ou polietilenoglicol 3350 associado ao Ringer lactato (PEG+RL); ou solução isotônica poliônica enteral (SIPE); ou solução isotônica poliônica enteral associada ao Ringer lactato (SIPE+RL); ou solução de cloreto de sódio a 0,9 por cento (NaCl). A avaliação laboratorial foi realizada nos tempos: imediatamente antes do início dos tratamentos (T0h); com seis horas (T6h) e ao final dos tratamentos (T12h); com 24 (T24h) e 48 horas (T48h) após T0h. Não ocorreu alteração significativa no lactato plasmático. Ocorreu apenas um discreto aumento nos valores da glicose e da insulina no tratamento SIPE, ocasionado pela presença de maltodextrina. O cortisol aumentou nos animais de todos os tratamentos, porém menor nos animais do SIPE. Conclui-se que os tratamentos não alteraram os valores da glicose, do lactato e da insulina em éguas hígidas e que a hidratação enteral em fluxo contínuo realizada no tratamento SIPE ocasionou menos estresse nos animais...

The aim of this study was to evaluate and compare the plasmatic lactate and glucose, serum insulin and cortisol in healthy non pregnant mares treated with: polyethylene glycol 3350 (PEG); or polyethylene glycol 3350 associated with Ringer lactate (PEG+RL), or enteral polionic isotonic solution (EPIS); or enteral polionic isotonic solution associated with Ringer lactate (EPIS+RL); or sodium chloride solution 0.9 percent (NaCl). Laboratory tests were carried out in the following moments: immediately before the start of treatment (T0h), at six hours (T6h) and at the end of treatment (T12h), with 24 (T24h) and 48 hours (T48h) after T0h. The lactate did not change significantly. There was a slight increase in glucose and insulin values in EPIS caused by the presence of maltodextrin. Cortisol increased in animals from all treatments, but this increase was lower in the animals in EPIS. It is concluded that the treatments did not alter the values of glucose, lactate and insulin in healthy mares and the enteral hydration in continuous flow done in the EPIS treatment caused less stress to the animals...

Enterografia por tomografia computadorizada: uma avaliação de diferentes contrastes orais neutros / Computed tomography enterography: a comparison of different neutral oral contrast agents

OBJETIVO: O objetivo deste estudo foi avaliar o desempenho de contrastes orais neutros, comparando a capacidade de distensão intestinal, a distinção da parede intestinal, a aceitação e os efeitos colaterais. MATERIAIS E MÉTODOS: Estudo prospectivo, randomizado e duplo-cego em 30 pacientes submetidos a tomografia computadorizada de abdome e pelve com administração de contraste oral neutro, divididos em três grupos: leite, água e polietilenoglicol. Os exames foram analisados quanto ao grau de distensão intestinal e distinção da parede intestinal por dois examinadores em consenso. Os pacientes responderam a um questionário referente ao sabor da solução ingerida e efeitos colaterais. Foram utilizados os testes Kruskal-Wallis e qui-quadrado para as análises estatísticas. RESULTADOS: Distensão intestinal adequada (calibre da alça maior que 2 cm) foi observada em 14 segmentos dos 40 estudados (35%) no grupo leite, em 10 segmentos (25%) no grupo água e em 23 segmentos (57%) no grupo polietilenoglicol (p = 0,01). O preparo com polietilenoglicol resultou na melhor distensão intestinal, porém apresentou o pior sabor e maior incidência de diarreia, referidos pelos pacientes. CONCLUSÃO: O preparo oral com polietilenoglicol promove maior grau de distensão intestinal do que quando se utiliza água ou leite, mas tem pior aceitação, relacionada ao seu sabor e frequência de diarreia.

OBJECTIVE: The purpose of this study was to assess the performance of neutral oral contrast agents, comparing intestinal distention, distinction of intestinal wall, acceptance and side effects. MATERIALS AND METHODS: Prospective, randomized, and double-blinded study involving 30 patients who underwent computed tomography of abdomen and pelvis with administration of neutral oral contrast agents, divided into three groups according the contrast agent type: milk, water, and polyethylene glycol. The images were consensually analyzed by two observers, considering the degree of bowel distention and intestinal wall distinction. The patients responded to a questionnaire regarding the taste of the ingested solution and on their side effects. Kruskal-Wallis and chi-square tests were employed for statistical analysis. RESULTS: Among 40 studied intestinal segments, appropriate bowel distension (intestinal loop diameter > 2 cm) was observed in 14 segments (35%) in the milk group, 10 segments (25%) in the water group and 23 segments (57%) in the polyethylene glycol group (p = 0.01). Preparation with polyethylene glycol resulted in the best bowel distention, but it presented the worst taste and highest incidence of diarrhea as reported by patients. CONCLUSION: Bowel preparation with oral polyethylene glycol results in higher degree of bowel distention than with water or milk, but presents worst acceptance related to its taste and frequency of diarrhea as a side effect.

Comparative study on toxic effects induced by oral or intravascular administration of commonly used disinfectants and surfactants in rats.

Accidental ingestion or injection of household products sometimes occurs due to their accessibility, but the toxic manifestations have not been well characterized when they are internally administered. The aim of this study was to investigate the toxic effects induced by ingestion or injection of different ionic surfactants and disinfectants in rats. The test drugs involved benzalkonium and benzethonium (BZK and BZT, both cationic surfactants used as disinfectants), alkyldiaminoethylglycine (AEG, an amphoteric surfactant used as a disinfectant), linear alkylbenzenesulfonate (LAS, an anionic surfactant), polyoxyethylene cetylether (PEC, a nonionic surfactant), chlorhexidine (CHX, not a surfactant but a disinfectant) and saline (control). Male Sprague-Dawley rats were administered one of the test drugs orally (p.o.), intravenously (i.v.) or intraarterially (i.a.). The fatal effects appeared rapidly (<30 min) in i.v.-administered rats, while taking hours (>5 h) in i.a./p.o.-administered rats after a dose of around LD(50) , although the progress and degree of toxic effects varied among the drugs tested. In intravascular administration, BZK and BZT were fatal at doses of 15-20 mg kg(-1) . Higher concentrations in lung and kidney than in blood were determined. CHX showed a high toxic effect compared with cationic surfactants. The rats administered anionic (LAS) or amphoteric (AEG) surfactant died in less than 24 h at doses over 100 mg kg(-1) . In p.o. administration, the toxic effects were concentration/dose-dependent, and all rats administered high doses of surfactants except for PEC died at 5-20 h. The overall toxic ranks could be: cationic surfactant/CHX> anionic/amphoteric surfactant > nonionic surfactant.

Modulation of the atopy patch test: tacrolimus 0.1% compared with triamcinolone acetonide 0.1%.

BACKGROUND: The atopy patch test (APT) is an in vivo model to study the induction of eczema by inhalant allergens in atopic dermatitis patients. We studied the effect of pretreatment with topical tacrolimus 0.1% on APT in nonlesional skin of patients with atopic dermatitis. METHODS: Nonlesional skin of the back of patients with atopic dermatitis (n = 8) was treated once daily for 3 weeks with tacrolimus 0.1% ointment. Cetomacrogol ointment (placebo) was used as a negative control and triamcinolone acetonide 0.1% ointment as positive control. Twenty-four hours after the last APT application, samples were taken from the three treated areas (t = 0 and 24 h) for immunohistochemical analysis. RESULTS: Pretreatment with tacrolimus ointment did not suppress nonlesional skin infiltrate, in contrast to triamcinolone acetonide. Furthermore, tacrolimus did not inhibit the induction of the APT macroscopically (t = 24 h). An equal influx of T cells, eosinophils, dendritic cells, CD64+ and Fc epsilon RI-positive cells was present compared with placebo. Only CD36+ and CD68-positive cells were inhibited compared with placebo. All cell types were significantly inhibited in triamcinolone acetonide-treated sites compared with placebo. CONCLUSIONS: Pretreatment with tacrolimus 0.1% ointment does not inhibit the APT reaction in patients with atopic dermatitis.

Development and stability of semisolid preparations based on a supercritical CO2 Arnica extract.

Conventional herbal drug preparations (HDP) based on Arnica montana L. have a low content of the active principles, sesquiterpene lactones, which show poor stability and low physical compatibility in semisolid formulations. Recently, an innovative supercritical carbon dioxide (CO2) extract with high sesquiterpene content has been marketed. Development of six semisolid preparations (cetomacrogol, polysorbate 60, polawax, anphyphil, natrosol and sepigel) based on this innovative CO2 extract is discussed. Stability of these preparations was investigated according to ICH guidelines. The evaluation of in vitro release of active constituents was performed using the cell method reported in the European Pharmacopoeia. Preliminary data on in vivo permeation of three selected formulations is demonstrated using the "skin stripping" test, according to the FDA, in healthy subjects. Analysis of sesquiterpene lactones within the extract and in vitro and in vivo studies was performed by RP-HPLC-DAD-MS method. The cetomacrogol showed the best release profile in the in vitro test, while in the in vivo test the best preparation resulted polysorbate 60 and polawax.

A double-blind clinical trial to compare the efficacy of an active based cream F14001 against a placebo non-active based cream for the treatment of pressure ulcers in a population of elderly subjects.

A double-blind clinical trial was conducted to compare the efficacy of an active based cream against a placebo non-active based cream in the healing of superficial pressure ulcers in a population of geriatric hospital patients and residents in community nursing homes. The active group showed a small significant beneficial effect at week four. The overall results of the trial also demonstrated a significant improvement in ulcer size over the duration of the trial period in both active and placebo groups.

Effects of fatty ethers and stearic acid on the gastrointestinal absorption of insulin.

Insulin degradation and inactivation occurs when the protein is given to an animal through oral route. The following compounds were assessed to determine their potential effect in increasing insulin absorption: polyoxyethylene (20) oleyl ether (Brij 99), polyoxyethylene lauryl ether and polyoxyethylene (20) cetyl ether (Brij 58). In this study the above compounds, along with stearic acid, were used to prepare granules with or without addition of insulin and were given orally to rabbits. Both glucose and insulin levels in blood were measured at different time intervals, the former with a glucometer and the latter using radioimmunoassay (RIA). To determine if there was a relationship between the glucose and the insulin levels in blood, a highly sensitive radioimmunoassay method was used to detect any small changes in the level of insulin in blood. A significant decrease in glucose blood levels (P less than 0.05) was obtained after oral administration of each of granules containing insulin. The greatest reduction was observed after half an hour of the oral administration of the granules. A similar response was obtained with the hypodermal injection of 1/5 of the oral insulin dose. Granules prepared with Brij 58 and containing insulin was the only formula that showed increase of insulin level in the blood. This was equivalent to 1/10 of the change produced after hypodermal injection of the hormone. In these experiments the changes in blood insulin levels were not directly proportional to the corresponding changes in blood glucose.

Effects of fatty ethers and stearic acid on the gastrointesinal absorption of insulin

Cuando se administra insulina a un animal atavés de la vía oral esta es inmediatamente degradada. El propósito de este trabajo es estudiar la efectividad de los compuestos que se indican a continuación para aumentar la absorción de insulina, estos son los siguientes: polietileno (20) cetil éter (Brij 58), polietileno (20) oleil éter (Brij 99) y polietileno lauril éter. Estos compuestos además de ácido esteárico se usaron para preparar gránulos con o sin insulina y fueron administrados oralmente a conejos. A estos animales se les midieron los niveles de glucosa e insulina a diferentes intérvalos de tiempo antes y después de la administración oral de los gránulos.l Se uso un glucómetro y el método de radioinmunoensayo (RIA) para hacer las respectivas medidas. Con el propósito de determinar si hay relación entre los niveles de glucosa e insulina en la sangre se uso el método de radioinmunoensayo por ser un método muy sensitivo que puede detectar pequeños cambios en la concentración de insulina en la sangre. Se observó un raducción significativa en los niveles de glucosa (P<0.05) después de administrarlos los gránulos. En otro experimento se inyectó 1/5 parte de la dósis oral de insulina y se observó una respuesta similar. Sin embargo, sólo los gránulos preparados con Brij 58, que contenían insulina produjeron altos niveles de insulina en la sangre. Esto fue equivalente a 1/10 del cambio producido por la inyección subcutánea de la hormona. En estos experimentos los cambios en insulina ...

Increase of the intestinal absorption of gentamicin and amikacin by a nonionic surfactant.

This study was concerned with the effect of Cetomacrogol (polyethylene glycol 1000 monocetyl ether), a nonionic surfactant, on the absorption of gentamicin and amikacin from the gastrointestinal tract of rats. A 200-mg dose of Cetomacrogol coadministered orally with 10 mg of gentamicin resulted in a mean peak gentamicin blood concentration of 14.1 microgram/ml, compared with 67.8 microgram/mg when the same gentamicin dose was administered intramuscularly. The area under the curve after administration of the oral mixture was 23% of that after the intramuscular dose. The rectal administration of the mixture resulted in a mean peak gentamicin blood level of 8.2 micrograms/ml, compares to 16.5 microgram/ml when the mixture was administered orally. A 50-mg dose of amikacin coadministered orally with 200 mg of Cetomacrogol resulted in a mean peak amikacin blood level of 13.3 microgram/ml, compared to 310 microgram/ml when this amikacin dose was administered intramuscularly. Cetomacrogol augments the intestinal absorption of gentamicin and amikacin in rats. If the toxicity of the combination in humans is limited, the combination may be potentially clinically useful.

Enteral administration of insulin in the rat.

1 The effect of the surfactant, Cetomacrogol 1000, on the absorption of insulin across the rectal mucosa has been studied. 2 Rectal administration of microenemata containing Cetomacrogal 1000 and insulin causes a rise in the plasma concentration of insulin and a consequent fall in the blood glucose concentration in diabetic and non-diabetic rats. 3 The hypoglycaemic response is dependent on both the concentration of surfactant and the dose of insulin administered. 4 The results suggest that the transport of insulin across the rectal mucosa is facilitated by Cetomacrogal 1000.