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1.
Support Care Cancer ; 25(11): 3545-3549, 2017 11.
Article in English | MEDLINE | ID: mdl-28653108

ABSTRACT

PURPOSE: Palmoplantar erythrodysesthesia (PPE) is one of the most frequent side effects during systemic treatment with pegylated liposomal doxorubicin (PLD, Caelyx®). PPE lesions show a range of symptoms, from numbness to painful erosions, and can have a major impact on the quality of life in affected patients. Previously, a possible pathomechanism of PPE was found in doxorubicin-treated patients based on radical formation in the skin. Here, a preventive strategy using a topically applied ointment with a high radical protection factor was investigated. METHODS: In this randomized placebo-controlled double-blind study the antioxidant-containing ointment was compared with a placebo ointment regarding PPE grade III occurrence, overall PPE grade I-III occurrence and PPE severity in PLD patients. The verum or placebo cream was topically applied for a period of 16 weeks, starting 3 days prior to the first cycle of chemotherapy. Clinical evaluations were carried out by a dermatologist prior to the first cycle of chemotherapy and every 4 weeks for the duration of 16 weeks. RESULTS: Thirty-two patients were enrolled in total, of which 17 (66%) completed the study. No PPE grade III was found in the verum group, while five out of seven patients (71%) had to be unblinded in the placebo arm due to PPE grade III (p = 0.003). General PPE occurrence of all grades was 60% under verum and 86% under placebo treatment. CONCLUSIONS: The preventive application of an antioxidant-containing ointment was shown to be significantly more effective in the prevention of PPE grade III compared to placebo treatment.


Subject(s)
Doxorubicin/analogs & derivatives , Hand-Foot Syndrome/etiology , Double-Blind Method , Doxorubicin/adverse effects , Doxorubicin/pharmacology , Female , Hand-Foot Syndrome/pathology , Humans , Middle Aged , Polyethylene Glycols/adverse effects , Polyethylene Glycols/pharmacology
2.
Acta Biomater ; 30: 388-396, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26621698

ABSTRACT

Recent advances in the field of dermatotherapy have resulted in research efforts focusing on the use of particle-based drug delivery systems for the stimuli-responsive release of drugs in the skin and skin appendages, i.e. hair follicles and sebaceous glands. However, effective and innocuous trigger mechanisms which result in the release of the drugs from the nanocarriers upon reaching the target structures are still lacking. For the first time, the present study demonstrated the photo-activated release of the model drug fluorescein isothiocyanate (FITC) from topically applied gold nanoparticle-doped bovine serum albumin (AuNPs-doped BSA) particles (approx. 545nm) using water-filtered infrared A (IRA) radiation in the hair follicles of an ex vivo porcine skin model. The IRA radiation-induced plasmonic heating of the AuNPs results in the partial decomposition or opening of the albumin particles and release the model drug, while control particles without AuNPs show insignificant release. The results demonstrate the feasibility of using IRA radiation to induce release of encapsulated drugs from plasmonic nanocarriers for the targeting of follicular structures. However, the risk of radiation-induced skin damage subsequent to repeated applications of high infrared dosages may be significant. Future studies should aim at determining the suitability of lower infrared A dosages, such as for medical treatment regimens which may necessitate repeated exposure to therapeutics. STATEMENT OF SIGNIFICANCE: Follicular targeting using nanocarriers is of increasing importance in the prophylaxis and treatment of dermatological or other diseases. For the first time, the present study demonstrated the photo-activated release of the model drug fluorescein isothiocyanate (FITC) from topically applied gold nanoparticle-doped bovine serum albumin (AuNPs-doped BSA) particles using water-filtered infrared A (IRA) radiation in the hair follicles of an ex vivo porcine skin model. The results demonstrate the feasibility of using wIRA radiation to induce release of encapsulated drugs for the targeting of follicular structures, and provide a new vision on the development of optically addressable delivery systems for controlled release of drugs in the skin and skin appendages, i.e. hair follicles and sebaceous glands.


Subject(s)
Drug Carriers , Gold , Hair Follicle/metabolism , Infrared Rays , Metal Nanoparticles/chemistry , Serum Albumin, Bovine , Administration, Topical , Animals , Cattle , Drug Carriers/chemistry , Drug Carriers/pharmacokinetics , Drug Carriers/pharmacology , Fluorescein-5-isothiocyanate/chemistry , Fluorescein-5-isothiocyanate/pharmacokinetics , Fluorescein-5-isothiocyanate/pharmacology , Gold/chemistry , Gold/pharmacokinetics , Gold/pharmacology , Hair Follicle/pathology , Serum Albumin, Bovine/chemistry , Serum Albumin, Bovine/pharmacokinetics , Serum Albumin, Bovine/pharmacology , Swine
3.
J Anim Physiol Anim Nutr (Berl) ; 99 Suppl S1: 29-35, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25865420

ABSTRACT

The current study aimed to determine the impact of acidified feed on apparent ileal starch digestibility, intestinal transport and barrier function and intestinal glucose transporter expression. The experiment included a control group and a treatment group with broilers fed a standard diet without or with 1.5% of a commercial organic acid product (64% formic acid, 25% propionic acid, 11% water). Broilers were fed with the experimental diets from hatching until days 32-35. Starch digestibility was determined using 0.2% titanium dioxide as ingestible marker. Gene expressions of the intestinal sodium glucose transporter 1 (SGLT-1) and glucose transporter 2 (GLUT-2) were analysed using qPCR analysis. Additionally, SGLT-1 function and chloride secretion were analysed in Ussing chamber experiments. Jejunal samples were sequentially exposed to 10 mm glucose, 100 µm phloridzin, 100 µm histamine and 100 µm carbachol. Apparent ileal starch digestibility (±SEM) of the control group (97.5 ± 0.35%) and the acid-treated group (97.0 ± 0.59%) did not differ (p = 0.674). The mean tissue conductance of intestinal samples obtained from the control group and the treatment group was similar [10.6 mS/cm(2) (±0.68) and 9.4 mS/cm(2) (±0.80) respectively (p = 0.147)]. The mean short-circuit currents (ΔIsc ) of the samples exposed to glucose, phloridzin, histamine and carbachol did not differ (p > 0.05). Additionally, no differences in the expression of SGLT-1 and GLUT-2 could be observed (p = 0.942, p = 0.413). Based on this study, the consumption of feed supplemented with organic acids was not associated with effects on ileal starch digestibility and functional traits of jejunal tissues, indicating that these additives have no major impact on the small intestinal function in broilers.


Subject(s)
Chickens , Dietary Supplements , Formates/pharmacology , Intestines/drug effects , Propionates/pharmacology , Starch/metabolism , Animal Feed/analysis , Animal Nutritional Physiological Phenomena , Animals , Diet/veterinary , Female , Formates/administration & dosage , Gene Expression Regulation/drug effects , Glucose Transporter Type 2/genetics , Glucose Transporter Type 2/metabolism , Intestines/physiology , Propionates/administration & dosage , Sodium-Glucose Transporter 1/genetics , Sodium-Glucose Transporter 1/metabolism , Starch/chemistry
4.
Poult Sci ; 93(8): 2060-8, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24902702

ABSTRACT

Several studies illustrated that the structure of feed, i.e., the particle size, particle-size distribution, and the physical form of the diet, affects the avian gastrointestinal function and health leading to changes in productive performance. However, investigations concerning the effects of feeding differently processed diets on laying hens are limited and primarily concentrated on bird performance. The current study examines the effect of feed processing on the gastrointestinal morphology and on the jejunal glucose transport of laying hens. In 8 replicates, a total of 384 hens (Lohmann Brown) aged 20 wk were randomly allocated to 8 different groups and fed over a period of 21 d in a 3-factorial design. Diets differed in 1) grinding method, either hammer or roller mill; 2) physical form, either mash or expandate; and 3) particle size, either coarsely or finely ground. During the experimental trial, the laying performance of each feeding group was recorded daily and the feed intake and BW determined weekly. After slaughtering, the weights of the pancreas, proventriculus, gizzard, and small intestine were measured. Villus lengths and crypt depths of the duodenum, jejunum, and ileum were determined. The jejunal electrogenic glucose transport was studied in Ussing chambers. Hens that received mash instead of expandate had higher proventriculus (P = 0.011), gizzard (P < 0.001), and pancreas (P = 0.019) weights, whereas the feeding of coarsely instead of finely ground diets led to higher gizzard weights (P < 0.001). Mash-fed hens showed longer duodenal (P < 0.001) and shorter ileal villi (P = 0.047) and increased duodenal villus height-to-crypt depth ratios (P < 0.001) than those given the expandate. Mash-fed hens had higher glucose transport rates than expandate-fed hens (P < 0.001). In conclusion, the feeding of coarsely ground as well as mash diets had stimulating effects on the development of the gastrointestinal organs. Moreover, the feeding of mash influenced the intestinal microstructure of the epithelium that was accompanied by higher glucose transport capacities.


Subject(s)
Animal Feed/analysis , Chickens/anatomy & histology , Chickens/metabolism , Food Handling , Gastrointestinal Tract/cytology , Glucose/metabolism , Jejunum/metabolism , Animals , Diet/veterinary , Female , Particle Size , Random Allocation , Reproduction/physiology
5.
Poult Sci ; 93(6): 1440-52, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24879694

ABSTRACT

Thermal treatments of feed and organic acids are known to affect the gastrointestinal microbiota in chickens. The present study evaluated the effect of different thermal processes including pelleting (P), long-term conditioning at 85°C for 3 min (L), expanding at 110°C (E110), and 130°C for 3 to 5 s (E130) as well as organic acid (63.75% formic acid, 25.00% propionic acid, and 11.25% water) inclusion levels (0, 0.75, and 1.5%) on gastrointestinal microbiota in broilers. In total, 960 one-day-old chicks were randomly assigned to 8 replicates using a 3 × 4 factorial arrangement. At d 35, bacterial cell numbers in the crop, ileum, and cecum, and bacterial metabolites in the crop, gizzard, ileum, and cecum were determined. The inclusion of 1.5% organic acids increased cell numbers of all clostridial clusters in the crop. The organic acid supplementation increased the propionic acid concentration in the crop and gizzard and there was a decrease in lactic acid concentration. In the ileum, the 0% organic acid group had the highest numbers of Lactobacillus spp. and enterobacteria. Inclusion of 1.5% organic acids increased ileal acetate concentration. Increasing the feed processing temperature led to an increase of lactobacilli in the crop and ileum, whereas clostridia and enterobacteria seemed unaffected. Similarly, lactate concentrations increased in the ileum, but short-chain fatty acids remained identical. In the crop, an increase for acetate was found for the E130 group compared with all other thermal treatments. In conclusion, our study demonstrated that thermal treatments and organic acid supplementation to broiler diets more markedly influenced the bacterial status of the crop compared with the downstream segments and their effects decreased along the length of gastrointestinal tract. Whereas organic acids markedly modified bacterial composition and activity in the crop, expansion increased lactobacilli and lactate in the crop and ileum.


Subject(s)
Amino Acids/metabolism , Chickens/physiology , Digestion/drug effects , Intestinal Mucosa/metabolism , Intestines/microbiology , Microbiota , Animal Feed/analysis , Animal Nutritional Physiological Phenomena/drug effects , Animals , Chickens/growth & development , Diet/veterinary , Dietary Supplements/analysis , Hot Temperature , Male , Random Allocation
6.
Poult Sci ; 93(5): 1159-71, 2014 May.
Article in English | MEDLINE | ID: mdl-24795308

ABSTRACT

Poultry feed is a potential vector for pathogens. Heat processing and organic acid treatments may decontaminate feed and can affect bird performance as well as feed digestibility. The present study was performed to investigate the effect of different thermal treatments including pelleting (P), long-term conditioning at 85°C for 3 min (L), or expanding at 110°C (E110) and 130°C for 3 to 5 s (E130) without or with 0.75 and 1.5% organic acid supplementation (63.75% formic acid, 25.00% propionic acid, and 11.25% water) on performance, nutrient digestibility, and organ weights of broilers. In total, 960 one-day-old broiler chicks were randomly assigned to 8 replicates using a 3 × 4 factorial arrangement. Performance variables were determined, and the relative organ weights and ileal and total amino acid (AA) digestibilities were measured at d 35. The organic acid inclusion linearly improved feed efficiency in the first week (P ≤ 0.05). The acid inclusion levels and thermal treatments had no significant effect on the performance variables at later intervals of the growing period of the birds. The L group showed the lowest ileal AA and CP digestibility. The inclusion of organic acids had a quadratic effect on total and ileal digestibility of isoleucine (P ≤ 0.05), whereas it had no significant effect on the ileal digestibility of other AA and nutrients. The relative weights of the jejunum and small intestine were significantly higher in the E130 group compared with P and L (P ≤ 0.05). In conclusion, our study demonstrated that long-term heat conditioning can decrease ileal nutrient digestibility, whereas pelleting and expansion, independently of organic acid addition, seemed to have no negative impact on broiler performance and nutrient digestibilities. Moreover, adding a blend of organic acids to broiler diets had neither positive nor negative effects on nutrient digestibility and final broiler performance. This indicates the feasibility of short-term thermal treatment and acid supplementation for hygienization of broiler feed without negatively influencing performance.


Subject(s)
Amino Acids/metabolism , Chickens/physiology , Digestion , Animal Feed/analysis , Animal Nutritional Physiological Phenomena/drug effects , Animals , Chickens/growth & development , Diet/veterinary , Dietary Supplements/analysis , Hot Temperature , Intestine, Small/metabolism , Male , Random Allocation , Weight Gain
7.
Eur J Pharm Biopharm ; 77(3): 465-8, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21056659

ABSTRACT

The application of particles in dermatology and cosmetology represents an emerging field and is closely connected with the question of risk assessment as the potential for, and consequences of, penetration of such particles into the living tissue has not been determined conclusively. In the medical sector, extensive research activities are in progress to develop particles, which can be used as efficient carriers for drug delivery through the skin barrier. In contrast, in cosmetic products, particles are mostly required to remain on the skin surface to fulfill their beneficial effect. Whereas the intercellular penetration of particles seems to be unlikely, the hair follicle has been shown to be a relevant penetration pathway for particles as well as an important long-term reservoir. It has been demonstrated that the penetration depth of the particles can be influenced by their size resulting in the possibility of a differentiated targeting of specific follicular structures. In the present review, the follicular penetration mechanisms and storage properties of particles are discussed.


Subject(s)
Cosmetics/pharmacokinetics , Nanoparticles/administration & dosage , Skin/metabolism , Animals , Biological Transport , Cosmetics/administration & dosage , Cosmetics/adverse effects , Drug Delivery Systems , Hair Follicle/drug effects , Hair Follicle/metabolism , Humans , Nanoparticles/adverse effects , Particle Size , Permeability , Skin/drug effects , Skin Absorption
8.
Skin Pharmacol Physiol ; 23(6): 320-7, 2010.
Article in English | MEDLINE | ID: mdl-20588083

ABSTRACT

The Organization for Economic Cooperation and Development (OECD) recommends caffeine as a reference substance for in vitro skin absorption tests using Franz diffusion cells (FDC). However, it has not been possible to investigate the follicular penetration pathway using this method until now. The aim of this study was to develop a technique to allow the examination of the follicular penetration pathway of a substance penetrating into the skin. The OECD standard method was therefore combined with the follicle closing technique (FCT), an established in vivo method. By using test skin of varying follicular densities, different penetration values were obtained for the test substance caffeine. The follicular penetration rate was determined by an indirect calculation after modifying the in vivo FCT for use in the in vitro FDC. This method is the first to allow the differentiation of penetration pathways by combining the OECD standard method (using the FDC) and the FCT. Caffeine showed a surprisingly high rate of penetration through the follicular shunts in vitro.


Subject(s)
Caffeine/pharmacokinetics , Hair Follicle/metabolism , Skin Absorption , Abdomen , Absorption , Administration, Cutaneous , Adult , Aged , Breast , Diffusion , Epidermis/metabolism , Female , Humans , Middle Aged , Skin/metabolism , Temperature
9.
Skin Pharmacol Physiol ; 21(3): 150-5, 2008.
Article in English | MEDLINE | ID: mdl-18523412

ABSTRACT

In the past, it was assumed that the intercellular route was the only relevant penetration pathway for topically applied substances. Recent results on follicular penetration obtained at the Center for Experimental and Applied Cutaneous Physiology, Charité - Universitätsmedizin Berlin, Germany, emphasize that the hair follicles represent a highly relevant and efficient penetration pathway and reservoir for topically applied substances.


Subject(s)
Cosmetics/metabolism , Hair Follicle/metabolism , Pharmaceutical Preparations/metabolism , Administration, Topical , Animals , Cosmetics/administration & dosage , Drug Carriers , Humans , Nanoparticles , Permeability , Pharmaceutical Preparations/administration & dosage , Skin Absorption
12.
Hoppe Seylers Z Physiol Chem ; 359(8): 867-71, 1978 Aug.
Article in English | MEDLINE | ID: mdl-30685

ABSTRACT

Tetrameric rabbit muscle aldolase is dissociated to the inactive monomer at strongly alkaline pH (pH greater than or equal to 12). As shown by sedimentation velocity, fluorescence emission, and specific activity, the final profiles of dissociation, denaturation, and deactivation run parallel. Increasing incubation time proves the enzyme to be metastable in the pH range of deactivation. At 10 less than pH less than 12 "hysteresis" of the deactivation-reactivation reaction is observed. Short incubation at pH greater than or equal to 12 leads to high yields of reactivation (greater than or equal to 60%), while irreversibly denatured enzyme protein is the final product after long incubation. The kinetics of reconstitution under essentially irreversible conditions (pH 7.6) can be described by a sequential uni-bimolecular mechanism, assuming partial activity of the isolated subunits. The kinetic constants correspond to those observed for the reactivation after denaturation at acid pH or in 6M guanidine. HCl. Obviously the pH-dependent deactivation and reactivation of aldolase at alkaline pH obeys the general transconformation/association model which has been previously reported to hold for the reconstitution of numerous oligomeric enzymes after denaturation in various denaturants.


Subject(s)
Fructose-Bisphosphate Aldolase , Muscles/enzymology , Alkalies , Animals , Chemical Phenomena , Chemistry , Enzyme Activation , Fluorescence , Hydrogen-Ion Concentration , In Vitro Techniques , Protein Conformation , Protein Denaturation , Rabbits
13.
Z Lebensm Unters Forsch ; 166(4): 228-33, 1978 May 29.
Article in German | MEDLINE | ID: mdl-354256

ABSTRACT

Analytical methods for the determination of polyphenols of malt, barley, hop, wort, and beer are described. Malt or barley tannins has hitherto not received as much study as hop tannin. Polyphenols or tannins are classified. Studies on non-biological hazes are discussed in relation to the haze problem in brewing. The leucoanthocyanins of malt differ from those of hops in ability to form hazes. Subfractionation of polyphenol concentrates on sephadex columns allows isolation of individual tannins.


Subject(s)
Beer/analysis , Edible Grain/analysis , Phenols/analysis , Anthocyanins/analysis , Catechin/analysis , Catechols/analysis , Coumarins/analysis , Fermentation , Hordeum/analysis , Tannins/analysis
14.
Dtsch Arztebl ; 67: 3288-93, 1970.
Article in German | MEDLINE | ID: mdl-11634882
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