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1.
Branched Polyethylenimine, 25 kDa (PEI), was blended with gellan gum, an anionic heteropolysaccharide, for partial neutralization of its excess positive charge to form gellan gum-polyethylenimine (GP) nanocomposites (NCs). Subsequently, we manipulated the amount of gellan gum for obtaining a series of NCs and characterized them for their size, charge and morphology. Among all the NCs, one member, named GP3, showed the best transfection efficiency in tested cell lines in comparison with the rest of the series, PEI, Lipofectamine and other commercial transfection agents and also exhibited minimum cytotoxicity. It was found to transfect primary cells of mouse skin with better efficiency than PEI and Lipofectamine and was able to protect the plasmid DNA from nucleases and serum proteins present in the blood. GP3 exhibited efficient intracellular delivery of plasmid as revealed by confocal studies while its intracellular presence was also confirmed by the knockdown of GFP expression (using GFP specific siRNA) and JNKII by quantifying proteins in cell lysates and by western blotting and hybridization, respectively. In vivo cytotoxicity studies in Drosophila showed lack of induction of stress response in the exposed organisms. Further, exposed organisms did not show any developmental delay or mortality and no morphological defects were observed in the emerged flies. In vivo gene expression studies in Balb/c mice revealed maximum expression of luciferase enzyme in spleen. The study suggests that GP3 may act as an efficient non-viral gene carrier with diverse biomedical applications.  相似文献   

2.
The antioxidant properties of different extracts of Halenia elliptica was investigated by employing various established in vitro systems. The results showed that various extracts possessed strong antioxidant activity in vitro, and the 70% methanol extract (ME) had the strongest antioxidant activity. Based on our in vitro results, ME was used for investigating the antioxidant properties of H. ellipticain vivo. The liver and kidney of CCl4-intoxicated animals exhibited a significant decrease in superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) levels. Additionally, these organs exhibited a significant increase in the level of malondialdehyde (MDA). These changes were significantly reversed, in a dose-dependent manner, after treatment with ME and the standard treatment Vitamin E. Thus, it may be concluded that the ME possesses potent antioxidant properties, and might be valuable natural source of antioxidants that could be applicable to both the medical and food industries.  相似文献   

3.
Hydrochloric thiothixene (HT) is an antipsychotic drug used in the treatment of various psychoses including schizophrenia, mania, polar disorder, and in behavior disturbances. However, because the psychotics often could not control their behaviors, the independent administration of antipsychotic drug based on medical order was difficult. The omissions of the administration often brought an unsatisfactory therapeutic efficacy. A novel injectable long-term control-released in situ gel of HT for the treatment of schizophrenia was developed based on biodegradable material polylactic acid (PLA). The optimum formulation of the injectable PLA-based HT in situ gel containing 15% (w/w) HT and 45% (w/w) PLA with benzyl benzoate was used as a gelling solvent. The results of the in vitro and in vivo studies showed that this in situ gel had a long-term period of drug release for several weeks and a good histocompatibility without any remarkable inflammatory reactions.  相似文献   

4.
Extracts of natural products have been used for many years for health benefits. We report on an in vitro and in vivo study into the anti-tumour efficacy of an aqueous extract of the mycelial form of basidiomycete, Funalia trogii. A variety of biological assays were used to show that a 4 h exposure of HT29, LNCaP, PC3, MCF-7 and MDA-MB-231 tumour cells to extract (0.5-5.0 mg/ml) resulted in significant cytotoxicity. In a clonogenic assay, IC50 values were found to range from 0.4-0.72 mg/ml; exposing fibroblast cells to the extract resulted in no cell kill. The extract resulted in significant cell kill in proliferating endothelial cells but had no toxicity to quiescent cells, this is useful in targeting tumour tissue since endothelial cells in tumours proliferate more rapidly that those found in other parts of the body. When tumours grown in immune compromised mice were injected intratumourally with extract (5 mg/ml twice a week for two weeks), a 9 day tumour growth delay was observed. The results indicate that the mycelial extract of F. trogii has a promising anti-tumour property.  相似文献   

5.
Hypericin (HY) is a naturally-occurring, potent photosensitizer. However, its lipophilicity limits its therapeutic applications. Our attempt is, thus, to develop a biodegradable nanocarrier for hypericin capable of preserving its antibacterial photoactivity. Amphiphilic block copolymers were synthesized to prepare hypericin-laden nanoparticles (HY-NPs). The antimicrobial photoactivity of HY-NPs was assessed; in vitro against biofilm and planktonic cells of methicillin resistant Staphylococcus aureus (MRSA) clinical isolates and in vivo on infected wounds in rats. Nanoparticles of 45 nm in diameter ensured higher amounts of reactive oxygen species upon irradiation. HY-NPs demonstrated superior inhibition of biofilm over planktonic cells. In vivo wound healing studies in rats revealed faster healing, better epithelialization, keratinization and development of collagen fibers when HY-NPs were applied. Determination of growth factors and inflammatory mediators in the wound area confirmed superior healing potential of nanoencapsulated hypericin suggesting that hypericin can join the era of antibiotic-free antimicrobial therapy.  相似文献   

6.
The objective was to investigate the transdermal delivery kinetics of zolmitriptan from an iontophoretic patch system in Yorkshire swine in vivo. Preliminary in vitro experiments showed that cumulative drug transport during a 6-h current application (0.25 mA cm−2) was independent of patch load (263.7 ± 92.7, 357.2 ± 85.9, 374.9 ± 74.3 and 335.9 ± 27.7 μg cm−2 for 7.5, 15, 45 and 90 mg patch loads, respectively; ANOVA, p < 0.05); the steady-state flux was ∼92 μg cm−2 h−1. The in vivo studies used multistep current profiles to demonstrate (i) rapid drug uptake and (ii) the effect of superposing a bolus input on basal drug levels. In both studies, zolmitriptan was detected in the blood after 2.5 min; drug levels were 7.1  1.7 and 10.4 ± 3.5 ng ml−1 at t = 30min in Studies 1 and 2, respectively. In Study 2, increasing current intensity from 0.2 to 1.4 mA (0.05-0.35 mA cm−2) at t = 180 min caused zolmitriptan levels to rise from 9.38 ± 0.93 ng ml−1 at t = 180 min to 13.57 ± 1.85 ng ml−1 at t = 190 min; a ∼50% increase in 10 min. Extrapolation of these results to humans suggests the feasibility of delivering therapeutic amounts of zolmitriptan at faster rates than those from existing dosage forms.  相似文献   

7.
New norcantharidin-conjugated hydroxypropyltrimethyl ammonium chloride chitosan derivatives (NCTD-HACCs) were synthesized and characterized by 1H NMR, Fourier-transform infrared spectroscopy (FT-IR), and wide-angle X-ray diffraction (WAXD). Two NCTD-HACCs with different degrees of substitution (DS) (12.2% and 24.8%) were obtained, which had good water solubility. NCTD was released from the NCTD-HACCs via hydrolysis, faster in pH 5.0 than pH 7.4 and presenting one biphasic drug release pattern with rapid release at the initial stage and slow release later. Fluorescence microscope and flow cytometry analysis demonstrated that the NCTD-HACC was endocytosized into MGC80-3 cells and the uptaken amount increased as incubation time. Compared with free NCTD, the NCTD-HACCs showed lower in vitro anti-tumor activity against human gastric cancer MGC80-3 cells, but higher in vivo tumor growth inhibition in S180 tumor-bearing mice. The in vivo near-infrared (NIR) fluorescence real-time imaging result showed the fluorescence intensity in tumor was much higher than that in heart, liver, spleen and lung (except kidney) after i.v. injection of the FITC-labeled NCTD-HACC2, indicating specific accumulation of the NCTD-HACC in tumor.  相似文献   

8.
The Electrically Heated Cigarette Smoking System Series K (EHCSS) produces smoke through the controlled electrical heating of tobacco. Evaluation of the EHCSS was accomplished by comparison with commercial and reference cigarettes, using International Organization for Standardization (ISO) and alternative puffing regimens based on nicotine exposures measured in a short-term clinical study. Using the alternative puffing regimen and compared with conventional cigarettes on a per cigarette basis, the EHCSS had 50–60% reductions in tar and nicotine; at least 90% reductions in carbon monoxide, nitrogen oxides, 1,3-butadiene, isoprene, acrylonitrile, polyaromatic hydrocarbons, hydrogen cyanide, aromatic amines, tobacco specific nitrosamines, and phenol; and least a 40% reduction in 2-nitropropane. Other important smoke constituents in EHCSS smoke were reduced as well. The in vitro studies showed similar large reductions in biological activity. Ames mutagenicity of total particulate matter (TPM) from the EHCSS was reduced by 70–90%; cytotoxicity of the TPM was reduced by approximately 82% and 65% for the gas–vapor phase. In vivo testing under ISO smoking conditions in the mouse skin painting assay demonstrated later dermal tumor onset, lower dermal tumor incidence, reduced dermal tumor multiplicity, and a lower proportion of malignant dermal tumors in EHCSS smoke condensate-exposed mice. Thirty-five day and 90-day nose-only inhalation studies in rats showed reductions in pulmonary inflammation and other biological activity, including histopathological endpoints. We conclude that under the conditions of these in vitro and in vivo studies, the EHCSS demonstrated significantly lower biological activity compared to conventional cigarettes, and may suggest the potential for reductions in human smokers.  相似文献   

9.
In vitro and in vivo erosion behaviour of erodible tablets consisting of glyceryl behenate and low-substituted hydroxypropylcellulose manufactured using three different methods: direct compression (DC), melt granulation (MG) and direct solidification (DS) was investigated. In vitro erosion behaviour was studied using gravimetric and scintigraphic methods. For scintigraphic investigations, the radiolabel was adsorbed onto activated charcoal and incorporated into tablets at a concentration that did not affect the erosion profile. A clinical study was carried out in six healthy volunteers using gamma scintigraphy. Tablet erosion was affected by the preparation method and was found to decrease in the order of preparation method, DC > MG > DS tablets. The mean in vivo onset time for all tablets (DC: 6.7 ± 3.8 min, MG: 18.3 ± 8.1 min, DS: 67 ± 18.9 min) did not differ significantly from in vitro onset time (DC: 5.3 ± 1 min, MG: 16.8 ± 3.9 min, DS: 61.8 ± 4.7 min). The mean in vivo completion times were found to be 36.6 ± 9.7 (DC tablets), 70 ± 18.3 min (MG tablets) and 192.5 ± 39.9 min (DS tablets). Among the three different erodible tablets, MG tablets showed the highest correlation between in vitro and in vivo mean erosion profile and suggested a potential platform to deliver controlled release of water-insoluble compounds.  相似文献   

10.
Oridonin (ORI), a diterpenoid compound with promising antitumor activity, was proved to possess potent antileukemia efficacies in vitro and in vivo recently. However, the development and application of ORI was limited by its poor solubility and rapid plasma clearance. The purpose of this study was to solve these problems. PEGylated oridonin linked with succinic acid (SA) as spacer moiety (PEG-SA-ORI conjugate) was synthesized. mPEG amines with four specifications of molecular weight (MW) were utilized. All polymeric conjugates showed satisfactory aqueous solubility and in vitro studies implied that the drug solubility and release features of conjugates were relevant to PEGs. The drug solubility increased more when the MW of PEG was lower, while more significant sustained-release effect was shown with higher PEG MW. Moreover, the release behaviors of conjugates showed a pH-sensitive property. In vivo pharmacokinetic studies demonstrated that the elimination half-life was prolonged in comparison with ORI solution. PEGylation could be a promising method to obtain better efficacy in the field of drug delivery system.  相似文献   

11.
In vitro models for hepatotoxicity testing are a necessity for advancement of toxicological research. Assessing the in vitro response requires in vivo validated gene sets reflective of the hepatotoxic phenotype. Cholestasis, the impairment of bile flow, is induced in C57BL/6J mice treated with cyclosporine A (CsA) to identify phenotype reflective gene sets. CsA treatment through oral gavage for 25 days induced cholestasis, as confirmed by histopathology and serum chemistry. Over 1, 4, and 11 days of CsA exposure gradual increases in serum markers were correlated to gene expression. This phenotype-directed analysis identified gene sets specific to the onset and progression of cholestasis, such as PPAR related processes and drug metabolism, by circumventing other effects of CsA, such as immunosuppression, found in dose*time group analysis. In vivo gene sets are enriched in publicly available data sets of CsA-treated HepaRG and primary mouse hepatocytes. However, genes identified within these gene sets did not overlap between in vivo and in vitro. In vitro regulated genes represent the initial response to cholestasis, whereas in vivo genes represent the later adaptive response. We conclude that the applicability of in vitro models for hepatotoxicity testing fully depends on a solid in vivo phenotype anchored analysis.  相似文献   

12.
The aim of this study was to develop microparticles containing nanoparticles (composite microparticles) for prolonged drug delivery with reduced burst effect in vitro and in vivo. Such composite microparticles were prepared with hydrophobic and biodegradable polymers [poly(ε-caprolactone), poly(lactic-co-glycolic) acid]. Ibuprofen was chosen as the model drug, and microparticles were prepared by the extraction technique with ethyl acetate as the solvent. Nanoparticles and microparticles and an ibuprofen solution (Pedea®) were administered subcutaneously at the dose of 1 mg of ibuprofen per kg to overnight-fasted rats (male Wistar). Composite microparticles showed prolonged ibuprofen release and less burst effect when compared to simple microparticles (without nanoparticles inside) or nanoparticles both in vitro (PBS buffer) and in vivo. Moreover, ibuprofen was still detected in the plasma after 96 h with composite microparticles. Consequently, it has been demonstrated that composite microparticles were able to reduce burst release and prolong the release of ibuprofen for a long period of time.  相似文献   

13.
Methanol extract of Symplocos cochinchinensis S. Moore leaves was evaluated for its in vitro and in vivo antioxidant activity. The total phenolic content of the extract was 230 mg of gallic acid equivalents/g extract. The extract showed very good scavenging activity on 2,2-diphenyl-picrylhydrazyl (DPPH) (IC50 620.30 ± 0.14 μg/ml), hydroxyl (IC50 730.21 ± 1.05 μg/ml), nitric oxide (IC50 870.31 ± 0.19 μg/ml) radicals, as well as high reducing power. The extract also showed strong suppressive effect on lipid peroxidation. In in vivo study CCl4 induced oxidative stress produced significant increase in SGOT, SGPT and LDH levels along with reduction in liver SOD, CAT, GSH and GPx levels. Pre-treatment of rats with the extract (250 and 500 mg/kg) for 7 days showed significant reduction in the levels of SGOT, SGPT and LDH compared to CCl4 treated rats. SOD, CAT, GSH and GPx levels were increased significantly due to treatment with the extract. The activity of the extract was comparable to the standard drug, silymarin (25 mg/kg). The results suggest that the leaves of S. cochinchinensis are a source of natural antioxidants.  相似文献   

14.
The aim of this laboratory-based study was to investigate some of the toxic effects induced by the venom from Hemiscorpious lepturus (H. lepturus). For this aim, pharmacological, histological, biochemical methods as well as complete blood cell count were used to assess these toxic actions. In addition, in vitro haemolysis studies on human washed blood suspension and cytotoxicity on cultured fibroblasts were also undertaken. In vitro pharmacological test was made on rat isolated ileal segment. To this end, the effects of the venom on the contractile responsiveness to acetylcholine were recorded using F30 transducer and Darco chart recorder. For assessment of the haemolytic potency, varying concentrations (2, 10, 20 and 40 μg/ml) of the venom were added to 0.5 ml of 5% washed human blood and after 30 min, 2, 4, 8, 12 and 24 h of exposure, the degree of lysis (extent of redness developed in the supernatant solution after centrifugation) were measured by ELISA method. Cytotoxicity potential of the venom was assessed by trypan blue exclusion test. The venom (0.1, 1 and 10 μg/ml) was mixed with confluent fibroblast cell culture and the extent cytotoxicity was assessed microscopically. In vivo studies were conducted by a subcutaneous administration of sub-lethal dose (10 μg) of the venom and after 7 days the skin, at the site of injection, and kidney samples were stained by H & E method and examined microscopically. In addition, biochemical assessments including measurement of serum aspartate aminotransferase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP) and amylase levels and urine analysis were made. The results showed that the venom prevented the relaxation phase of the acetylcholine-induced contractions on the isolated ileal segments and finally produced sustained spasmodic contractions. This spasmodic action was abolished by 1 μM atropine. The venom produced haemolysis of red blood cells in a concentration-dependent and duration-of-exposure manner, with 100% of haemolysis produced after 24 h following exposure to 40 μg/ml of venom. While cultured fibroblasts cells were more sensitive and disintegrated after 15 min of exposure to 1 μg/ml of the venom. Histological findings showed evidences of excessive inflammatory responses accompanied with signs of necrosis in the skin at the site of injection as well as structural damage in the nephrones. There was a significant rise in the serum enzymes. In addition, the number of the RBCs were reduced. The urine showed positive readings for proteinuria, blood and intact RBCs. The overall results suggest that the venom from H. lepturus primarily is a cytotoxic agent and has haemolytic, nephrotoxic and to some extent hepatotoxic activity.  相似文献   

15.
Helicobacter pylori is one of the most common infections worldwide. In most individuals it consists in a lifelong host-pathogen relationship without consequences, but in some subjects it is associated with peptic ulcer disease and gastric cancer. Polymorphism in genes that code bacterial virulence factors, cagA and vacA, are independently associated with the infection severe outcomes and are geographically diverse. In the last decade, accumulated knowledge allowed to characterize typical H. pylori strain patterns for all the major human populations; patterns that can be used to study the origin of specific human groups. Thus, the presence or absence of cagA, cagA EPIYA genotypes, and vacA subtypes can be used as tools to study not only the geographic origin of specific human populations, but also to identify markers of historical contact between different ethnicities. We report here a study including a set of native Amazon Amerindians that had supposedly been some, but little, contact with European Brazilian colonizer and/or African slaves. They harbor H. pylori strains in a mixed pattern with Asian and Iberian Peninsula characteristics. It is possible that this finding represents H. pylori recombination upon short contact between human groups. Alternatively, it could be due to a founder effect from a small cluster of Asian origin native Americans.  相似文献   

16.
Ritonavir, an HIV protease inhibitor, is successfully used for the prevention and treatment of HIV infections. Ritonavir pharmacokinetics are complicated by inhibition, induction and pharmacogenetics of cytochrome P450 (CYP) enzymes mediating its clearance. This investigation revealed that CYP2J2, along with CYP3A4/5 and CYP2D6, efficiently metabolizes ritonavir, and to a CYP2J2-specific (minor) metabolite. Chemical inhibition of ritonavir metabolism, clearance, KI/kinact and abundance of CYP2J2 in liver microsomes were evaluated and then applied to an in vitroin vivo static scaling model to estimate the contribution of each isozyme, as a function of CYP abundance, activity, and genotype. Disposition of the CYP2J2-specific metabolite was also evaluated in vivo. In plasma, metabolite abundance was well above previously reported levels with circulating concentrations measured at 2 μM for the main hydroxylisopropyl metabolite. Ritonavir and metabolite plasma profiles were simulated using Simcyp®. A modest (2–6%) contribution of CYP2J2 to ritonavir clearance is predicted which increases to more than 20% in subjects carrying CYP2D6 poor metabolizer polymorphisms and CYP3A4 irreversible inhibition. These results indicate that minor drug metabolizing enzymes could become quantitatively important in RTV clearance if main metabolic pathways are impeded.  相似文献   

17.
Aconitine (AC) is a highly toxic alkaloid from bioactive plants of the genus Aconitum, some of which have been widely used as medicinal herbs for thousands of years. In this study, we systematically evaluated the potential role of P-glycoprotein (P-gp) in the mechanisms underlying the low and variable bioavailability of oral AC. First, the bidirectional transport of AC across Caco-2 and MDCKII-MDR1 cells was investigated. The efflux of AC across monolayers of these two cell lines was greater than its influx. Additionally, the P-gp inhibitors, verapamil and cyclosporin A, significantly decreased the efflux of AC. An in situ intestinal perfusion study in rats showed that verapamil co-perfusion caused a significant increase in the intestinal permeability of AC, from 0.22 × 10− 5 to 2.85 × 10− 5 cm/s. Then, the pharmacokinetic profile of orally administered AC with or without pre-treatment with verapamil was determined in rats. With pre-treatment of verapamil, the maximum plasma concentration (Cmax) of AC increased sharply, from 39.43 to 1490.7 ng/ml. Accordingly, a 6.7-fold increase in the area under the plasma concentration–time curve (AUC0–12 h) of AC was observed when co-administered with verapamil. In silico docking analyses suggested that AC and verapamil possess similar P-gp recognition mechanisms. This work demonstrated that P-gp is involved in limiting the intestinal absorption of AC and attenuating its toxicity to humans. Our data indicate that potential P-gp-mediated drug–drug interactions should be considered carefully in the clinical application of aconite and formulations containing AC.  相似文献   

18.
Water-soluble crude polysaccharide from a brown alga Turbinaria ornata (TCP) was screened for its antioxidant and anti-inflammatory potential. The major functional groups of polysaccharide were analyzed by Fourier Transmission-Infra Red (FT-IR). In vitro free radical quenching and total antioxidant activity of TCP was investigated by 1, 1-diphenyl-2-picryl hydrazyl (DPPH), nitric oxide (NO) scavenging, lipid peroxidation (LPO) inhibition and ABTS radical assay. Evaluation of anti-inflammatory activity of TCP was performed using carrageenan-induced paw edema in rats and vascular permeability test in mice. Phytochemical analysis of TCP showed the presence of carbohydrates, proteins and polyphenols further, the FT-IR analysis of TCP showed the presence of functional groups of sugar moiety, uronic acids and sulfate groups. TCP showed maximum LPO, NO and DPPH inhibition of 78.04%, 38.82% and 80.21% at a concentration of 1000, 125 and 500 μg/ml respectively. Oral administration of TCP (2.5, 5, 10, 20 mg/kg) reduced the paw edema considerably (p < 0.05) in a dose dependent manner compared to carrageenan induced rats. Similarly, oral administration of TCP (3, 10, 30 mg/kg) evoked a significant (p < 0.05) dose dependent inhibitory effect on vascular permeability in mice. Altogether, these results suggest that the crude polysaccharide of T.ornata could be considered as a potential antioxidant and anti-inflammatory agent.  相似文献   

19.
20.
Ginkgolide B (GKB), the major active component of Ginkgo biloba extracts, exerts both stimulatory and inhibitory effects on apoptotic signaling. Previous studies by our group demonstrated that ginkgolide treatment of mouse blastocysts induces apoptosis, decreases cell number, hinders early postimplantation blastocyst development, and increases early-stage blastocyst death. Here, we further investigate the effects of GKB on oocyte maturation, and subsequent pre- and postimplantation development in vitro and in vivo. In our experiments, GKB induced a significant reduction in the rate of oocyte maturation, fertilization, and in vitro embryonic development. Treatment of oocytes with 1–6 μM GKB during in vitro maturation (IVM) led to increased resorption of postimplantation embryos and decreased placental and fetal weights. Data obtained using an in vivo mouse model further disclosed that consumption of drinking water containing 3–6 μM GKB led to decreased oocyte maturation and in vitro fertilization, as well as early embryo developmental injury, specifically, inhibition of development to the blastocyst stage in vivo. To our knowledge, this is the first study to investigate the impact of GKB on maturation of mouse oocytes, fertilization, and sequential embryonic development.  相似文献   

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