RÉSUMÉ
The Expert Panel for Cosmetic Ingredient Safety reviewed newly available studies since their original assessment in 2002, along with updated information regarding product types and concentrations of use, and confirmed that Aluminum Starch Octenylsuccinate is safe as a cosmetic ingredient in the practices of use and concentration as described in this report.
Sujet(s)
Sécurité des produits de consommation , Cosmétiques , Aluminium , Amidon/toxicité , Succinates/toxicité , Cosmétiques/toxicitéRÉSUMÉ
Ethylene-vinyl alcohol samples containing 27 and 38 % ethylene were used to prepare blends containing 30 and 50 % thermoplastic starch (TPS) plasticized with glycerol. Their biodegradability and cytotoxicity were studied by different techniques (XRD, DSC, TGA, CA, ATR-FTIR, SEM). TPS presence significantly affected copolymer behavior, as confirmed by the appearance of OH IR 1000-1170 cm-1 bands and overall reduction of EVOH crystallinity, melting point, thermal stability and hydrophobicity. Biodegradation was more efficient in the presence of TPS and resulted in the formation of a robust biofilm by a consortium of three bacteria. A lower ethylene content facilitated biodegradation, making the material easier to metabolize. The mineralization percentages obtained after a 40-day bioassay at 45 °C were up to 66 % (EVOH-27/TPS 50:50). In vitro cytotoxicity assay demonstrated no cytotoxicity before and after biodegradation. EVOH/TPS blends are presented as a potential environmentally friendly alternative to pure synthetic polymers.
Sujet(s)
Glycérol , Amidon , Éthylènes , Polyvinyles , Amidon/toxicité , Résistance à la tractionRÉSUMÉ
Pharmaceutical pollutants, a vital type of emerging contaminants, have attracted researchers to study their removal from water. In this research, Corn starch nanoparticles (CSNP) have been synthesized and characterized using various analytical techniques. The synthesized CSNP was used for the biosorption of two pharmaceutical drugs, ibuprofen (IBU) and sulfamethoxazole (SUL). The influence of various experimental conditions was optimized through batch study with the removal efficiency of 86.33 % (IBU) and 85.80 % (SUL) at pH 2 and 3, initial concentration of 10 mg/L, 0.01 g of CSNP dosage. The biosorption of IBU follows Temkin, and SUL follows Langmuir isotherm models. The toxicological assessment was performed using the seeds of Vigna mungo (VM) and Vigna radiata (VR) and zebrafish to evaluate the toxic effects of pollutants on these organisms. The LC50 of IBU and SUL on zebrafish before the biosorption process was 209.50 mg/L and 338.84 mg/L. After biosorption, the LC50 values increase to 1435.82 mg/L for IBU and 1317.04 mg/L for SUL. Thus, CSNP is an efficient biosorbent for removing the pharmaceutical pollutants to protect ecological systems.
Sujet(s)
Nanoparticules , Polluants chimiques de l'eau , Adsorption , Animaux , Concentration en ions d'hydrogène , Ibuprofène/toxicité , Cinétique , Nanoparticules/toxicité , Préparations pharmaceutiques , Amidon/toxicité , Sulfaméthoxazole/toxicité , Eau , Polluants chimiques de l'eau/analyse , Zea mays , Danio zébréRÉSUMÉ
Hemorrhage remains one of the direct causes of high mortality. The development of ideal hemostatic materials with sound ability to deal with severe wound is urgent needed. Although starch-based hemostatic powder has been widely used, hydrous physiological environments severely hamper its binding to the target tissue, thereby limiting the effectiveness in hemostasis. Herein, inspired by mussel adhesive protein, a novel injectable tissue-adhesive hydrogel (St-Dopa hydrogel) composed of starch, succinic anhydride and dopamine was developed in situ by enzymatic crosslinking. The results show that St-Dopa hydrogels were intimately integrated with biological tissue and formed robust barriers to reduce blood loss. St-Dopa hydrogels exhibited superior capacity for in vitro and in vivo hemostasis as compared with chitin hydrogels. In addition to the ease of operation, St-Dopa hydrogels exhibited rapid sol-gel transition, porous microscopic morphology, good swelling ratio and biodegradability, tissue-like elastomeric mechanical properties and excellent cyto/hemo-compatibility. These results suggest that this newly developed St-Dopa hydrogel is a promising biological adhesive and hemostatic material.
Sujet(s)
Hémorragie/traitement médicamenteux , Hémostase/effets des médicaments et des substances chimiques , Hémostatiques/usage thérapeutique , Hydrogels/usage thérapeutique , Amidon/usage thérapeutique , Adhésifs tissulaires/usage thérapeutique , Animaux , Lignée cellulaire , Dopamine/analogues et dérivés , Dopamine/usage thérapeutique , Dopamine/toxicité , Module d'élasticité , Hémostatiques/synthèse chimique , Hémostatiques/toxicité , Hydrogels/synthèse chimique , Hydrogels/toxicité , Mâle , Test de matériaux , Souris , Porosité , Lapins , Amidon/analogues et dérivés , Amidon/toxicité , Anhydrides succiniques/composition chimique , Anhydrides succiniques/usage thérapeutique , Anhydrides succiniques/toxicité , Suidae , Adhésifs tissulaires/synthèse chimique , Adhésifs tissulaires/toxicité , Substances viscoélastiques/synthèse chimique , Substances viscoélastiques/usage thérapeutique , Substances viscoélastiques/toxicitéRÉSUMÉ
Various nanoparticles have been developed for tumor-targeted drug delivery. However, nanoparticles with effective targeting and intelligent release capacity are still deficient. Herein, we present new pH-responsive and neutral charged nanoparticles for tumor-targeted anticancer drug delivery. Oxidized starch was synthesized and simultaneously modified by cholesterol and imidazole to obtain amphiphilic cholesterol/imidazole modified oxidized-starch (Cho-Imi-OS). Cho-Imi-OS easily self-assembled into nanoparticles by dialysis. Curcumin was selected as model drug to be encapsulated into the hydrophobic core of nanoparticles. The results showed that curcumin would effectively accumulate in cancer cells by encapsulating into the nanoparticles owing to the nano-sized structure and near neutral charged property of nanoparticles. Curcumin was released faster at pH 5.5 than that at pH 7.4 from the curcumin-loaded nanoparticles (Cur-NPs), indicating the pH-triggered release capacity of Cur-NPs after endocytosis by endosomes since the pH is low to 5.0â¼6.0 in endosomes. Naturally, Cur-NPs showed significantly strong inhibitory effect on cancer cells.
Sujet(s)
Antinéoplasiques/pharmacologie , Curcumine/pharmacologie , Vecteurs de médicaments/composition chimique , Nanoparticules/composition chimique , Cellules A549 , Animaux , Antinéoplasiques/composition chimique , Cholestérol/composition chimique , Cholestérol/toxicité , Curcumine/composition chimique , Vecteurs de médicaments/toxicité , Libération de médicament , Tests de criblage d'agents antitumoraux , Humains , Concentration en ions d'hydrogène , Imidazoles/composition chimique , Imidazoles/toxicité , Nanoparticules/toxicité , Lapins , Amidon/composition chimique , Amidon/toxicitéRÉSUMÉ
Several starch derivatives bearing urea groups (TUCAST, MTUCAST, and PTUCAST) based on 6-O-chloroacetylated starch (CAST) were successfully designed and synthesized. FT-IR, 1H NMR spectroscopy, and elemental analysis were carried out to identify the structural characteristics of starch derivatives. The antioxidant activity of starch derivatives was tested by superoxide-radical scavenging and hydroxyl-radical scavenging assays. Their antifungal activity against Fusarium oxysporum f. sp. cucumebrium Owen, Phomopsis asparagus, and Fusarium oxysporum f. sp. niveum was estimated by hyphal measurement. Furthermore, the antibacterial activity against Escherichia coli and Staphylococcus aureus was evaluated by optical density method. Compared to starch, the products bearing urea groups showed enhanced antifungal action as well as an excellent antioxidant and antibacterial activities. Their bioactivities decreased roughly in the order of PTUCAST > MTUCAST > TUCAST > CAST > starch, which matched with the electron-withdrawing property of the different substituted groups of urea. Besides, the cytotoxic activity of starch and synthesized derivatives against L929 cells was evaluated using CCK-8 assay in vitro and all samples showed weak cytotoxicity. The results suggested that these novel starch derivatives possessing satisfactory bioactivities could be widely used in the food industry.
Sujet(s)
Amidon/composition chimique , Amidon/pharmacologie , Urée/composition chimique , Acétylation , Animaux , Antibactériens/composition chimique , Antibactériens/pharmacologie , Antibactériens/toxicité , Antifongiques/composition chimique , Antifongiques/pharmacologie , Antifongiques/toxicité , Lignée cellulaire , Piégeurs de radicaux libres/composition chimique , Piégeurs de radicaux libres/pharmacologie , Piégeurs de radicaux libres/toxicité , Test de matériaux , Souris , Amidon/toxicitéRÉSUMÉ
It is important to control immediate hemorrhage and prevent infection simultaneously in the wound management. However, most of hemostatic materials are associated with low efficiency of hemostasis, poor biocompatibility and lack of antimicrobial properties. A kind of starch-based macroporous sponges (KR-Sps) immobilized covalently with antimicrobial peptide KR12 using highly efficient thiol-ene photo click reaction were developed. The physical properties of these sponges could be fine-tuned by varying the ratio of modified starch/HS-PEG-SH and the polymer concentration. The in vitro and vivo results demonstrated that KR-Sps induced thrombosis, shortened clotting time and reduced the blood loss at bleeding site. Besides, KR12 immobilized sponge exhibited inherent antimicrobial properties against Gram (+) and (-) bacteria and methicillin-resistant Staphylococcus aureus (MRSA), which could maintain at least 5 days. Therefore, KR-Sps were believed to be an excellent candidate as hemostatic and antimicrobial product for the intraoperative wound management.
Sujet(s)
Antibactériens/pharmacologie , Peptides antimicrobiens cationiques/pharmacologie , Hémostatiques/pharmacologie , Protéines immobilisées/pharmacologie , Amidon/composition chimique , Éponges chirurgicales , Animaux , Antibactériens/composition chimique , Antibactériens/toxicité , Peptides antimicrobiens cationiques/composition chimique , Peptides antimicrobiens cationiques/toxicité , Matériaux biocompatibles/composition chimique , Matériaux biocompatibles/pharmacologie , Matériaux biocompatibles/toxicité , Escherichia coli/effets des médicaments et des substances chimiques , Hémostatiques/composition chimique , Hémostatiques/toxicité , Protéines immobilisées/composition chimique , Protéines immobilisées/toxicité , Mâle , Staphylococcus aureus résistant à la méticilline/effets des médicaments et des substances chimiques , Souris , Tests de sensibilité microbienne , Polyéthylène glycols/composition chimique , Polyéthylène glycols/toxicité , Porosité , Rat Sprague-Dawley , Solanum tuberosum/composition chimique , Staphylococcus aureus/effets des médicaments et des substances chimiques , Staphylococcus epidermidis/effets des médicaments et des substances chimiques , Amidon/toxicitéRÉSUMÉ
Nonalcoholic fatty liver disease (NAFLD) is the early stage of many metabolic syndromes. The intervention of NAFLD can prevent its further development into severe metabolic syndromes. Given the inefficiency and side effects of chemical drugs for treating NAFLD, the hepatic-targeted nanocarriers loaded with bioactive compounds may offer a more effective and acceptable strategy for eliminating NAFLD. Here we developed hepatic-targeted oxidized starch-lysozyme (OSL) nanocarriers to specifically deliver resveratrol (Res) to liver tissue in order to maximize its therapeutic efficiency. The hepatic targeting was achieved using covalently conjugated galactose (Gal), which is recognized by the asialoglycoprotein receptors specifically expressed in hepatocytes. In steatotic HepG2 cell model, treatment with hepatic-targeted Gal-OSL/Res nanocarriers enhanced the cellular Res uptake and anti-lipogenesis capabilities, and effectively decreased triglyceride accumulation by modulating AMP-activated protein kinase (AMPK)/silent information regulation 2 homolog 1(SIRT1)/fatty acid synthase (FAS)/sterol regulatory element-binding protein-1c (SREBP1c) signaling pathway. In mice, Gal-OSL increased Res delivery into liver tissues and increased their hepatic effective concentration in liver. Most importantly, Gal-OSL/Res nanocarriers effectively reversed NAFLD and recovered hepatic insulin sensitivity of NAFLD mice to the healthy state. Furthermore, Gal-OSL/Res efficiently ameliorated lipid deposition and insulin resistance by modulating AMPK/SIRT1/FAS/SREBP1c signaling pathway and downregulated insulin receptor substrate-1 (IRS-1) phosphorylation at serine 307 in liver. These findings suggested that the hepatic-targeted Gal-OSL nanocarriers delivering Res could potentially serve as a safe and promising platform for NAFLD and other liver related diseases.
Sujet(s)
Foie/métabolisme , Nanoparticules/administration et posologie , Stéatose hépatique non alcoolique/traitement médicamenteux , Resvératrol/administration et posologie , Animaux , Alimentation riche en graisse , Galactose/administration et posologie , Galactose/composition chimique , Galactose/pharmacocinétique , Galactose/toxicité , Cellules HepG2 , Humains , Mâle , Souris de lignée C57BL , Micelles , Lysozyme/administration et posologie , Lysozyme/composition chimique , Lysozyme/pharmacocinétique , Lysozyme/toxicité , Nanoparticules/toxicité , Stéatose hépatique non alcoolique/métabolisme , Amidon/administration et posologie , Amidon/composition chimique , Amidon/pharmacocinétique , Amidon/toxicitéRÉSUMÉ
The unique physicochemical and functional characteristics of starch-based biomaterials and wound dressings have been proposed for several biomedical applications. Film dressings of cornstarch/hyaluronic acid/ ethanolic extract of propolis (CS/HA/EEP) were prepared by solvent-casting and characterized by attenuated total reflectance/Fourier transform infrared spectroscopy, scanning electron microscopy, gas chromatography/mass spectrometry, light transmission, opacity measurements, EEP release, equilibrium swelling, and in vitro and in vivo evaluations. The CS/HA/0.5%EEP film dressing exhibited higher antibacterial activity against Staphylococcus aureus (2.08 ± 0.14 mm), Escherichia coli (2.64 ± 0.18 mm), and Staphylococcus epidermidis (1.02 ± 0.15 mm) in comparison with the CS, CS/HA, and CS/HA/0.25%EEP films. Also, it showed no cytotoxicity for the L929 fibroblast cells. This wound dressing could effectively accelerate the wound healing process at Wistar rats' skin excisions. These results indicate that enrichment of cornstarch wound dressings with HA and EEP can significantly enhance their potential efficacy as wound dressing material.
Sujet(s)
Antibactériens/pharmacologie , Acide hyaluronique/composition chimique , Pansements occlusifs , Propolis/pharmacologie , Amidon/composition chimique , Animaux , Antibactériens/composition chimique , Antibactériens/toxicité , Poulets , Escherichia coli/effets des médicaments et des substances chimiques , Femelle , Fibroblastes/effets des médicaments et des substances chimiques , Acide hyaluronique/toxicité , Hydrolyse , Lysozyme/composition chimique , Propolis/composition chimique , Propolis/toxicité , Rat Wistar , Staphylococcus aureus/effets des médicaments et des substances chimiques , Staphylococcus epidermidis/effets des médicaments et des substances chimiques , Amidon/toxicité , Cicatrisation de plaie/effets des médicaments et des substances chimiquesRÉSUMÉ
The potential use of cellulose nanofibers (CNFs) as a reinforcing agent in banana starch-based nanocomposite films was investigated. CNFs were isolated from banana peel (Musa paradisiaca) by enzymatic hydrolysis. Banana starch-based nanocomposite films were prepared with CNFs using the casting method. CNFs effect on cell viability and on nanocomposite films properties' was investigated. The cytotoxicity of CNFs was assessed on Caco-2 cell line. CNFs were not cytotoxic at 50-2000 µg/mL. However, CNFs above 2000 µg/mL significantly decreased cell viability. Topography analysis showed that the incorporation of CNFs modified the film structure. The nanocomposites exhibited a complex structure due to strong interactions between CNFs and starch matrix, promoting a remarkable improvement on mechanical and water barrier properties, opacity and UV light barrier compared to the control film. CNFs can offer a great potential as reinforcing material for starch-based nanocomposite films, producing a value-added food packaging from a waste material.
Sujet(s)
Cellulose/toxicité , Fruit/composition chimique , Musa/composition chimique , Nanocomposites/toxicité , Nanofibres/toxicité , Amidon/toxicité , Cellules Caco-2 , Survie cellulaire/effets des médicaments et des substances chimiques , Cellulose/composition chimique , Module d'élasticité , Emballage alimentaire/instrumentation , Humains , Hydrolyse , Nanocomposites/composition chimique , Nanofibres/composition chimique , Perméabilité , Amidon/composition chimique , Résistance à la traction , Eau/composition chimiqueRÉSUMÉ
In this present study, original, biodegradable, biocompatible, non-immunogenic and non-poisonous folic acid (FA) decorated reductive-responsive starch-based microcapsules (FA-RSMCs) were designed and fabricated via the sonochemical method for targeted delivery and controlled release of hydrophobic drugs. A green hydrophobic fluorescent dye, Coumarin 6 (C6), was encapsulated into the FA-RSMCs as a substitute of hydrophobic drugs. The as-synthesized C6-loaded FA-RSMCs were characterized by DLS, SEM and TEM. The results indicated that the obtained C6-loaded FA-RSMCs had an appropriate size range and could enter into the bloodstream with their splendid stability. Moreover, C6-loaded FA-RSMCs showed a high selectivity to Hela cells, and a brilliant targeted drugs delivery and reductive-responsive release ability for hydrophobic drugs, particularly for hydrophobic anti-cancer drugs.
Sujet(s)
Vecteurs de médicaments/composition chimique , Acide folique/composition chimique , Amidon/composition chimique , Ondes ultrasonores , Cellules A549 , Transport biologique , Capsules , Préparations à action retardée , Libération de médicament , Cellules HeLa , Humains , Amidon/métabolisme , Amidon/toxicitéRÉSUMÉ
There is an urgent need for developing nanocarrier of excellent biocompatibility which can selectively release drugs at desired locations that can increase intratumoral drug concentration and reduce side effects. Herein, we developed a highly biocompatible nanocarrier made of oxidized starch in delivering doxorubicin (DOX) for enhanced anti-cancer therapy. The 30% oxidized starch can spontaneously self-assemble into 30-50â¯nm spherical nanoassemblies under physiological concentrations. DO30 nanoassemblies possessed negligible toxicity in several cell lines and ICR mice, in contrast to severe toxicity of synthetic polyacrylic acid (PAA), both of which are carboxyl-abundant polymers. The biocompatible DO30 was further decorated with cyclic RGD (Arg-Gly-Asp-Phe-Cys) peptides via PEG linker to target αvß3 integrin overexpressed on HepG2 cells. RGD-PEG-DO30/DOX demonstrated an enhanced tumor-targeting ability and anti-cancer property in vitro and in vivo. In general, RGD-oxidized starch nanoassemblies showed a great potential as a new type of safe and effective nanocarrier for anti-cancer therapy.
Sujet(s)
Antibiotiques antinéoplasiques/pharmacologie , Doxorubicine/pharmacologie , Vecteurs de médicaments/composition chimique , Tumeurs/traitement médicamenteux , Amidon/composition chimique , Résines acryliques/composition chimique , Résines acryliques/toxicité , Animaux , Antibiotiques antinéoplasiques/usage thérapeutique , Matériaux biocompatibles/composition chimique , Matériaux biocompatibles/toxicité , N-oxydes cycliques/composition chimique , Doxorubicine/usage thérapeutique , Femelle , Cellules HepG2 , Humains , Intégrine alphaVbêta3/métabolisme , Mâle , Souris , Souris de lignée ICR , Nanoparticules/composition chimique , Nanoparticules/toxicité , Oligopeptides/composition chimique , Oxydoréduction , Amidon/toxicité , Distribution tissulaire , Tests de toxicité , Tests d'activité antitumorale sur modèle de xénogreffeRÉSUMÉ
Carboxymethyl Assam Bora rice starch coated superparamagnetic iron oxide nanoparticles (CM-ABRS SPIONs) were chemically synthesized by co-precipitation method and particle size reduction was controlled by high energy homogenization process. Effects of various process variables (polymer concentration, homogenization speed and cycles) were optimized on the basis of average particle size (Z-average) and polydispersity index (PDI) of CM-ABRS SPIONs. The optimized CM-ABRS SPIONs were characterized for their particle size, surface morphology, electrokinetic potential, chemical interactions, crystallinity, magnetic properties, and targeting potential in presence of external magnetic field. In vitro localization of CM-ABRS SPIONs in a suspension of FITC (Fluorescein isothiocyanate) labeled RBCs (Red blood cells; hematocrit value; 45% (v/v)) was conducted inside a square glass capillary (500â¯×â¯500⯵m2 cross section) in the presence of an externally applied magnetic field (Msâ¯=â¯150â¯mT), simulating the case of magnetic drug targeting (MDT) approach. The aggregation dynamics of CM-ABRS SPIONs inside a micro capillary was observed with respect to time (tâ¯=â¯0 to 600â¯s), which shows proportionality to time of exposure to the externally applied magnetic field. This in vitro study acts as an important platform for design and optimization of active targeted drug delivery system.
Sujet(s)
Vecteurs de médicaments/composition chimique , Vecteurs de médicaments/synthèse chimique , Nanoparticules de magnétite/composition chimique , Oryza/composition chimique , Amidon/analogues et dérivés , Techniques de chimie synthétique , Vecteurs de médicaments/toxicité , Hémolyse/effets des médicaments et des substances chimiques , Humains , Phénomènes magnétiques , Taille de particule , Amidon/synthèse chimique , Amidon/composition chimique , Amidon/toxicitéRÉSUMÉ
The safety profile of the ingredients used in topical dosage forms and its evaluation is an issue of utmost importance. A suitable equilibrium between safety and efficacy is crucial before promoting a dermatological product. The aim of this work was to assess the safety and biological effects of starch-based vehicles (St-BV) used in such products. The hazard, exposure and dose-response assessment were used to characterize the risk of each ingredient. The EpiSkin™ assay and human repeat insult patch tests were performed to compare the theoretical safety assessment to in vitro and in vivo data. The efficacy of the St-BV was studied using biophysical measurements in human volunteers during 28â¯days, showing that all ingredients and their combinations were safe for the consumer. Tissue viability determined using the EpiSkin™ testing reached values between 84.0⯱â¯5.0% and 98.0⯱â¯8.6% after application of St-BV, which were considered as non-irritant to the skin. These observations were confirmed by the in vivo studies where the St-BV did not induce any sensitization on the volunteers, being safe for human use. Moreover, St-BV increased skin hydration and microcirculation, emerging as an attractive alternative to chemical raw materials.
Sujet(s)
Aluminium/toxicité , Cosmétiques/toxicité , Nanocapsules/toxicité , Peau/effets des médicaments et des substances chimiques , Amidon/toxicité , Succinates/toxicité , Sécurité des produits de consommation , Émulsions , Humains , Microcirculation/effets des médicaments et des substances chimiques , Tests épicutanés , Appréciation des risques , Peau/vascularisation , Peau/métabolisme , Tests de toxicité , Eau/métabolismeRÉSUMÉ
Hypertension causes neuronal damage and apoptosis in the brain. Diazoxide is a drug used in the treatment of hypertension however, its effect on 5-hydroxyindole acetic acid (5-HIAA) and dopamine amines in adult animal models remains unclear. The purpose of this study was to determine the effect of oligoelements on 5-HIAA and dopamine in the brain of adult rats treated with diazoxide METHODS: Male Fisher rats (weight 250g) were treated as follows: Group I, NaCl 0.9% (control); group II, tracefusin® (1.5mL/rat); group III, diazoxide (20mg/rat) and group IV, tracefusin® (1.5mL/rat)+diazoxide (20mg/rat). All doses were intraperitoneally administered on daily basis for four consecutive days. After the last administration, the brain of the animals was obtained and dissected in cortex, hemispheres (striatum) and cerebellum/medulla oblongata to measure the levels of 5-HIAA, dopamine, lipid peroxidation and total ATPase activity through validated methods. RESULTS: Dopamine and 5-HIAA levels decreased significantly in the group that received trace elements and diazoxide in the hemisphere regions, while in cerebellum/medulla oblongata, dopamine levels increased significantly in the groups that received diazoxide alone in. Lipid peroxidation in all brain regions increased significantly in the groups that received trace elements and diazoxide. ATPase dependent of calcium and magnesium decreased in the groups that received diazoxide alone or combined with trace elements in cerebellum/medulla oblongata regions. CONCLUSION: The present results suggest that the use of trace elements and diazoxide alters metabolism of dopamine and 5-HIAA amines. Free radicals may be involved in this effect.
Sujet(s)
Antihypertenseurs/pharmacologie , Diazoxide/pharmacologie , Hypertension artérielle/traitement médicamenteux , Stress oxydatif/physiologie , Amidon/toxicité , Talc/toxicité , Tartrates/toxicité , Oligoéléments/toxicité , Adenosine triphosphatases/métabolisme , Animaux , Encéphale/effets des médicaments et des substances chimiques , Encéphale/métabolisme , Encéphale/anatomopathologie , Modèles animaux de maladie humaine , Dopamine/métabolisme , Association médicamenteuse , Acide 5-hydroxy-indole-3-acétique/métabolisme , Hypertension artérielle/métabolisme , Hypertension artérielle/anatomopathologie , Perfusions parentérales , Peroxydation lipidique/effets des médicaments et des substances chimiques , Peroxydation lipidique/physiologie , Mâle , Stress oxydatif/effets des médicaments et des substances chimiques , Rats de lignée F344RÉSUMÉ
In this paper, the starch was firstly modified by quaternary reagent to obtain cationic starch. Then self-assembled folate-biotin-quaternized starch nanoparticles were prepared by a one-pot synthesis via N,N'-dicyclohexylcarbodiimide/N-hydroxysuccinimide/4-dimethylaminopyridine-mediated esterification reaction. The physicochemical properties of the prepared folate-biotin-quaternized starch nanoparticles were characterized. The average diameter of folate-biotin-quaternized starch nanoparticles was 109 nm with polydispersity index of 0.183 and zeta potential of 28.59 mV. The folate-biotin-quaternized starch nanoparticles were used as co-carrier of siRNA and doxorubicin with satisfactory drug loading capacity (6.98%) and encapsulation efficiency (69.66 %), and siRNA could be efficiently encapsulated at 40/1 weight ratio of doxorubicin/folate-biotin-quaternized starch nanoparticles to siRNA. The folate-biotin-quaternized starch nanoparticles could effectively protect siRNA from degradation of serum RNAase for up to 48 h. The release characteristics of doxorubicin and siRNA from folate-biotin-quaternized starch nanoparticles were studied in different pH environment and the release behaviors of two drugs were all pH sensitive. The folate-biotin-quaternized starch nanoparticles as a potential co-carrier of anticancer agents and gene drugs was expected to achieve future practical application in vitro and in vivo.
Sujet(s)
Antibiotiques antinéoplasiques/administration et posologie , Biotine/analogues et dérivés , Doxorubicine/administration et posologie , Vecteurs de médicaments/composition chimique , Acide folique/analogues et dérivés , Petit ARN interférent/administration et posologie , Amidon/analogues et dérivés , Animaux , Antibiotiques antinéoplasiques/composition chimique , Antibiotiques antinéoplasiques/toxicité , Biotine/toxicité , Doxorubicine/composition chimique , Doxorubicine/toxicité , Vecteurs de médicaments/toxicité , Libération de médicament , Érythrocytes/cytologie , Érythrocytes/effets des médicaments et des substances chimiques , Acide folique/toxicité , Hémolyse/effets des médicaments et des substances chimiques , Test de matériaux , Modèles moléculaires , Nanoparticules/composition chimique , Nanoparticules/toxicité , Nanoparticules/ultrastructure , Petit ARN interférent/composition chimique , Petit ARN interférent/toxicité , Rats , Amidon/toxicitéRÉSUMÉ
Timpanismo intestinal agudo em cavalos e mulas introduzidos em pastagens de Panicum maximum cv. Tanzânia, cv. Massai e cv. Mombaça são relatados na região norte do Brasil, durante o período das chuvas. As causas são desconhecidas, porém, tem sido sugerido que estão associados a um maior armazenamento de carboidratos não fibrosos na gramínea. Este trabalho teve por objetivos realizar um levantamento epidemiológico dos surtos de cólicas ocorridos no Estado de Rondônia, assim como contribuir com o estudo da ação dos carboidratos de P. maximum na ocorrência da doença. Para isso foram realizadas visitas em 10 propriedades que apresentaram casos da enfermidade. Em duas propriedades foram introduzidos equinos no mês de março e foram coletadas amostras de pastagens para a determinação de energia digestiva, lisina, matéria seca, carboidratos solúveis em água, carboidratos solúveis em éter, carboidratos não fibrosos, fibra de detergente neutra, fibra de detergente ácido, lignina, amido, gordura e proteína bruta. Essas determinações foram realizadas, também, em amostras de pastagens de P. maximum de outras propriedades onde não estavam ocorrendo cólicas e das pastagens de Cynodon dactylon de onde provinham os equinos. Os resultados mostraram que os surtos de cólica ocorrem na época de chuva, quando as pastagens estão rebrotando com uma morbidade de 31,6%, e letalidade de 86,1%. As análises bromatológicas mostraram uma diferença significativa nas concentrações de amido (P=0,0072) do P. maximum que causou cólica (8,3 % e 9,2%), quando comparado com o P. maximum das outras propriedades (0,9% e 4,3%) e com o Tifton, utilizado previamente na alimentação dos mesmos equinos (0,2% e 0,8%). Em outra fazenda a doença foi reproduzida experimentalmente em um equino, no mês de março administrando P. maximum cortado contendo 6,5% de amido. A mesma pastagem não causou cólica quando foi administrada a equinos entre os meses de novembro a fevereiro, com 2,7% a 5,1% de amido. Estes resultados sugerem que a causa das cólicas em equídeos em pastagens de P. maximum, na época de rebrote, é o alto conteúdo de amido das mesmas.(AU)
Acute intestinal bloat occurs in horses and mules introduced into sprouting Panicum maximum cv. Tanzania, cv. Massai and cv. Mombaça pastures in northern Brazil during the rainy season. It has been suggested that the disease is due to high concentrations of non-structural carbohydrates in this grass. The paper aimed to study outbreaks of colics in the state of Rondônia, Brazil and contribute to the knowledge of the carbohydrates contained in P. maximum as the cause of the disease. For this, ten farms which had cases of intestinal bloat were visited. On two farms, horses were introduced into such a toxic pasture. Samples of pasture were collected for determination of digestible energy, lysine, dry matter, water soluble carbohydrates, ether soluble carbohydrates, non-fiber carbohydrates, neutral detergent fiber, acid detergent fiber, lignin, starch, and fat. Samples of P. maximum pastures from neighboring farms, where the disease was not occurring, and from Cynodon dactylon pastures where the horses had been grazing before were also collected. The results showed that colics occur in the rainy season in sprouting pasture with a morbidity of 31.6%, and lethality of 86.1%. The pastures which induce colic showed significantly (P=0.0072) higher starch concentration (8,3 and 9,2%) than pastures of P. maximum which did not cause colic (0,9 and 4,3%) as well as the Cynodon dactylon pastures ingested previously by the horses (0.2 and 0.8%. On another farm, the disease was produced experimentally in a horse receiving in the feeder P. maximum collected from a toxic pasture with 6.5% of starch. The same pasture did not cause colic from November to February with starch content of 2.7 to 5.1%. It is suggested that the cause of colic in equids ingesting sprouting pasture of P. maximum is the high starch content of this pasture during the groth period.(AU)
Sujet(s)
Animaux , Amidon/toxicité , Pâturage/effets indésirables , Colique , Equidae , Métabolisme glucidique , Maladies gastro-intestinales/médecine vétérinaireRÉSUMÉ
The preparation of aminoethyl hydroxypropyl starch collagen peptide (AEHPS-COP) was via an enzyme-catalyzed reaction between amino groups in aminoethyl hydroxypropyl starch (AEHPS) and γ-carboxamide groups in collagen peptide (COP) by using microbial transglutaminase (MTGase) as biocatalyst. As an intermediate reactant, AEHPS was synthesized from hydroxypropyl starch (HPS) and 2-chloroethylamine hydrochloride (CEH). The chemical structures of HPS, AEHPS and AEHPS-COP were characterized by Fourier transform infrared spectroscopy (FT-IR) and 13C nuclear magnetic resonance (13C NMR). The reaction conditions that influenced the degree of substitution (DS) of AEHPS-COP were optimized, which included the reaction temperature, the reaction time, the mass ratio of collagen peptide to aminoethyl hydroxypropyl starch and the pH value. In addition, in vitro antioxidant activities of AEHPS-COP were evaluated through the scavenging activity of hydroxyl and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. Furthermore, the methylthiazol tetrazolium (MTT) assay was applied to investigate the cell viability of AEHPS-COP. The results indicated that the AEHPS-COP exhibited better cell viability to L929 mouse fibroblast cells. Therefore, the AEHPS-COP showed a promising potential application in cosmetic, biomedical and pharmaceutical fields.
Sujet(s)
Collagène/composition chimique , Piégeurs de radicaux libres/composition chimique , Fragments peptidiques/composition chimique , Amidon/analogues et dérivés , Animaux , Survie cellulaire/effets des médicaments et des substances chimiques , Éthylamines/composition chimique , Piégeurs de radicaux libres/synthèse chimique , Piégeurs de radicaux libres/toxicité , Rats , Amidon/synthèse chimique , Amidon/composition chimique , Amidon/toxicitéRÉSUMÉ
The potential toxicity of corn starch fiber was assessed and compared to polydextrose, a commonly used bulking agent with a long history of safe use in the food supply. Groups of male and female Crl:CD(SD) rats were fed 0 (control), 1,000, 3,000, or 10,000 mg/kg-bw/day corn starch fiber in the diet for 90 days. The polydextrose reference article was offered on a comparable regimen at 10,000 mg/kg-bw/day. Following a single gavage dose of [14C]-corn starch fiber on study day 13 or 90, the mass balance of the test article was assessed by analysis of excreta samples collected from 0 to 168 h post-dose. There were no toxicologically or biologically relevant findings in any of the test article-treated groups. The few minor differences observed between the corn starch fiber and polydextrose exposed groups were considered to be due to normal biological variation. Following [14C]-corn starch fiber dosing, nearly complete excretion of the administered dose occurred over 168 h post-dosing, with the majority excreted in the feces. The dietary no-observed-adverse-effect level of corn starch fiber after 90 days was 10,000 mg/kg-bw/day. Similar toxicity profiles for corn starch fiber and polydextrose were observed due to the structural and compositional similarities of these materials.
Sujet(s)
Radio-isotopes du carbone/analyse , Fibre alimentaire/toxicité , Fèces/composition chimique , Amidon/toxicité , Administration par voie orale , Animaux , Fibre alimentaire/administration et posologie , Relation dose-effet des médicaments , Femelle , Additifs alimentaires/administration et posologie , Additifs alimentaires/toxicité , Glucanes/administration et posologie , Glucanes/toxicité , Mâle , Dose sans effet nocif observé , Rats , Rat Sprague-Dawley , Amidon/administration et posologieRÉSUMÉ
PURPOSE: To evaluate in vitro cytotoxicity/biocompatibility as well as in vivo tolerability of the novel polysaccharide 4DryField® PH, certified for haemostasis and adhesion prevention. METHODS: In vitro cytotoxicity/viability testing according to ISO EN 10,993 using murine and human tumour cell lines incubated with 4DryField® PH (PlantTec Medical GmbH). Using a rat model the impact of 4DryField® PH on animals viability and in vivo effects were macro- and micropathologically assessed. RESULTS: In vitro testing revealed no cytotoxic effect of 4DryField® PH nor enhancement of viability to tumour cell lines. In vivo viability of rats was unimpaired by 4DryField® PH. Bodyweight loss in animals with abdominal injury plus treatment with 4DryField® PH was in the range of controls and less than in injured rats without treatment. At day 7 after surgery no formation of adhesions, neither macroscopic nor histological remnants nor signs of foreign body reaction were present in animals without injury. In animals with peritoneal injury and 4DryField® PH application, histopathological observation revealed minor residuals of polysaccharide in the depth of wound cavity embedded in a thickened subperitoneal layer; however, with a suggested intact neoperitoneum. The presence of mononuclear cells surrounding polysaccharide particles in varying states of degradation was observable as well. CONCLUSION: 4DryField® PH is not cytotoxic and does not enhance viability of tumour cell lines. High dose of 4DryField® PH of 1.09 g/kg bodyweight is well tolerated and reduces weight loss in animals with peritoneal injury. The biocompatibility of 4DryField® PH can be rated as being excellent.