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1.
RATIONALE: Rhinophototherapy has been shown to be effective in the treatment of allergic rhinitis. Considering that phototherapy with ultraviolet light (UV) induces DNA damage, it is of outstanding importance to evaluate the damage and repair process in human nasal mucosa. METHODS: We have investigated eight patients undergoing intranasal phototherapy using a modified Comet assay technique and by staining nasal cytology samples for cyclobutane pyrimidine dimers (CPDs), which are UV specific photoproducts. RESULTS: Immediately after last treatment Comet assay of nasal cytology samples showed a significant increase in DNA damage compared to baseline. Ten days after the last irradiation a significant decrease in DNA damage was observed compared to data obtained immediately after finishing the treatment protocol. Difference between baseline and 10 days after last treatment was not statistically significant. Two months after ending therapy, DNA damage detected by Comet assay in patients treated with intranasal phototherapy was similar with that of healthy individuals. None of the samples collected before starting intranasal phototherapy stained positive for CPDs. In all samples collected immediately after last treatment strong positive staining for CPDs was detected. The number of positive cells significantly decreased 10 days after last treatment, but residual positive staining was present in all the examined samples. This finding is consistent with data reported in skin samples after UV irradiation. Cytology samples examined two months after ending therapy contained no CPD positive cells. CONCLUSION: Our results suggest that UV damage induced by intranasal phototherapy is efficiently repaired in nasal mucosa.  相似文献   

2.
The permeability of liposome entrapping insulin through the nasal mucosa of rabbit has been studied and compared with the permeability of insulin solution with or without pretreatment by sodium glycocholate (GC). Insulin entrapped in liposome was not detected in the receiver cell using the diffusion cells with the nasal mucosa. On the other hand, permeability of insulin entrapped in liposome increased after the pretreatment of GC. The phospholipids which result from liposomes, were not observed in the receiver. Also, the GC remaining in the nasal mucosa was measured. Considering the mechanism of permeation of insulin entrapped in liposome through the nasal mucosa, the GC remaining in the nasal mucosa may cause the lysis of liposomes.  相似文献   

3.
The absorption of insulin (from porcine pancreas) in rabbits after the nasal administration of aqueous preparations containing insulin and five kinds of cyclodextrins (CyDs) in phosphate buffer solution at pH 7.0 was investigated. Without CyD, the insulin and glucose levels in plasma were unchanged, whereas a marked increase in the plasma levels of insulin and a decrease in glucose concentrations were observed following the simultaneous administration of insulin and CyD such as alpha- and heptakis (2,6-di-O-methyl)-beta-CyD (DM-beta-CyD). The largest enhancing effect on the nasal absorption of insulin was obtained by DM-beta-CyD. To evaluate the duration of the absorption-enhancing effect of CyDs, preadministration (administration of CyD 0.5, 6, 12 and 24 h before insulin administration) was performed. The area under plasma concentration-time curve (AUC) and Cmax of insulin significantly decreased with the preadministration of DM-beta-CyD 6, 12 and 24 h before nasal administration. The absorption-enhancing effect disappeared 24h after the preadministration. These findings demonstrate that CyDs enhance the nasal absorption of insulin, and the recovery of the membrane transport barrier function in nasal mucosa is achieved, at the latest, 24 h after the administration of CyDs.  相似文献   

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Exposure to ultraviolet B (UV-B) light is recognized to induce suppression of certain immune responses, particularly delayed hypersensitivity. However, its effect on cytotoxic T lymphocyte (CTL) activity, of major importance in the resistance to viruses and tumours, has not been assessed to the same extent. In this study five normal subjects, seropositive for herpes simplex virus (HSV), underwent a standard course of broadband UV-B therapy, as used in the treatment of psoriasis. They received whole-body irradiation thrice weekly for four weeks with incremental doses dependent on skin type. Blood samples were taken immediately before, at two time points during, and at the end of the therapy. An HSV-specific CTL assay was performed using autologous B cells transformed with Epstein-Barr virus as targets. No consistent modulation in CTL activity was obtained as a result of the therapy. The CTLs were separated into CD4 and CD8 subsets by positive selection and, again, no effect of irradiation on CTL activity within each of these two populations was observed. In contrast, the natural killer (NK) cell activity, assessed by the lysis of K562 cells, was significantly reduced at the first time point after the initiation of the phototherapy in all five subjects, and it continued to decline as the treatment progressed. Thus a differential effect of UV-B exposure on cytotoxic activity has been demonstrated: the HSV-specific CTL response is unchanged, while the NK response is suppressed.  相似文献   

6.
The permeability of nalmefene hydrochloride (NH) across different regions of ovine nasal mucosa was investigated in vitro. Five different regions of ovine nasal mucosa (superior turbinate mucosa, middle turbinate mucosa, inferior turbinate mucosa, posterior septum mucosa, and anterior septum mucosa) were studied. The results showed that the permeability coefficients of NH through different regions of nasal mucosa were different, and the suitable regions for the absorption of NH were the middle turbinate mucosa, the posterior septum mucosa and the superior turbinate. At the same time, the middle turbinate mucosa was the largest region among the five regions, thus it was the main absorption region for NH. The high uniformity of the middle turbinate mucosa also made it the most suitable model for the permeation of NH in vitro.  相似文献   

7.
The utility of the absorption promoters, sodium glycocholate (GC-Na), ethylenediamine dihydrochloride (EDTA-2Na), sodium caprylate (Cap-Na) and sodium salicylate (Sal-Na), in the intranasal administration of human fibroblast interferon-beta (HuIFN-beta) in rabbits was investigated. The optimal amount of added EDTA-2Na, Cap-Na and Sal-Na with respect to HuIFN-beta was examined for nasal absorption in the powder dosage form. Formulations of HuIFN-beta with GC-Na showed greatly enhanced intranasal HuIFN-beta absorption, as compared to the other absorption promoters. The results of a stability study on HuIFN-beta in homogenates of nasal mucosa suggested that GC-Na behaved as a hydrolysis inhibitor in the nasal mucosa and maintained the activity of HuIFN-beta.  相似文献   

8.
The present study was aimed to formulate and evaluate in situ thermoreversible intranasal gel of an antimigraine drug rizatriptan benzoate. The poloxamer 407 and carbopol 934 were used as thermoreversible and mucoadhesive polymers respectively. The gels were prepared with cold method. The phase transition temperature was determined with visual method. The gels were evaluated for their pH, mucoadhesive strength, in vitro release and ex vivo drug permeation through goat nasal mucosa. The histopathological study of the nasal mucosa was carried out to check for its damage during drug permeation. The 18 % w/v poloxamer solution was found to be showing phase transition at physiologic conditions (34–35 °C). As the percentage of carbopol 934 was increased from 0.1 to 0.5 % w/v the gelling temperature was found to be decreased. All formulations were showing mucoadhesive strength above 4,000 dynes/cm2. Drug permeation studies have indicated that the drug permeation rate can be increased by using carbopol 934 above 0.3 % w/v concentration. The histopathological evaluation of nasal mucosa after drug permeation study has not shown any evidence of damage. Thus in situ thermoreversible mucoadhesive gel of rizatriptan benzoate can be a promising approach to treat migraine.  相似文献   

9.
Radix Bupleuri is widely used in traditional medicine for the treatment of fever, pain, and inflammation associated with influenza or the common cold. The essential oil extracted from the herb is generally claimed to play the major role in the efficacious treatment of fever. The purpose of the present study was to formulate an intranasal delivery system for the essential oil in an aqueous solution used in the form of nasal spray. From 450 g Radix Bupleuri was extracted the essential oil in the amount of about 0.2 ml, which was slightly water-soluble and viscous with low-fluidity. In order to dissolve the essential oil evenly in the aqueous solution, tween-80 (TW-80, used in 10% (w/v) solution), propylene glycol (PG) and diethylene glycol monoethyl ether (TC) were selected as the favorable solubilizing agents, whose amount was respectively determined by L16(4(5)) orthogonal design. An aqueous solution with clarity and no ciliotoxicity was prepared when TW-80 8% (v/v), PG 14.4% (v/v) and TC 14.4% (v/v) were added. Employed to evaluate the acute toxicity, the rats grew well and were kept active and healthy within 14 d after an intranasal administration of this preparation at the dose of oil from 10 g Bupleuri/kg (50-fold higher than the clinical dose), indicating that there would be no serious toxicity at the normal dose. Intranasal administration of this preparation to 2 kg rabbits with fever induced by subcutaneous injection of turpentine decreased body temperature markedly (0.5, 0.8 and 1.0 degrees C respectively at the dose of oil from 1, 2 and 4 g Bupleuri/body). In addition, the administration significantly reduced fever in 200 g rats induced by intramuscular injection of colicine suspension (0.6 degrees C at the dose of oil from 0.8 g Bupleuri/body). The results suggest that the formulation of nasal spray for the essential oil from Radix Bupleuri can be potentially effective in the treatment of fever.  相似文献   

10.
A hollow-type suppository containing gentamicin (GM) in its cavity was prepared using Witepsol H-15 (H-15) mixed with glyceryl-1-monooctanoate (MO) or MO alone in the body of the suppository (type I) and a suppository (type II) containing GM and MO in the cavity was constructed using H-15 in the body of the suppository. Without MO, GM (60 mg) was not absorbed (plasma GM levels less than 1 microgram/ml). However, the absorption of GM from the rectum of rabbits was enhanced by coadministered MO in types I and II. Even when the amount of GM was decreased to 6 mg (1/10), GM was observed in the plasma (Cmax, 3.5 +/- 0.3 micrograms/ml) after administration of the suppository made from MO mixed with H-15. The enhancing effect of MO on the rectal absorption of GM could not be further increased by incorporating an amount of MO larger than approximately 300 mg into the suppository. This study demonstrates that MO can be used in the two types of hollow suppositories as an effective enhancing agent of rectal absorption of poorly absorbed drugs such as GM.  相似文献   

11.
Liposomes have been identified as effective immunological adjuvants and have potential for the intranasal and oral delivery of protein antigen. Anionic MLV liposomes were prepared by dehydration–rehydration method. For coating, liposomes were incubated in chitosan solution. Efficiency of coating was confirmed by the evaluation of FITC-labelled chitosan-coated liposomes using a fluorescent microscope. Liposomes morphology and size were studied by optical microscope and size analyzer. Mucoadhesion potential of liposomes was evaluated in human nose by gamma-scintigraphy using 99mTc-labelled liposomes. Rabbits (4 animals per group) were nasally immunized in weeks 0, 2 and 4 by liposomes encapsulated with 40 Lf TT. Bleedings and lavage collections were taken place in weeks 3 and 6, and IgG and sIgA titers were measured by ELISA method.Liposomes had a mean diameter of 2.38 μm. Loading of TT was 58.7 ± 12.4%. The mucoadhesion (clearance rate from nose) of both coated and non-coated liposomes was similar (P > 0.05). Among the immunized animals, the highest nasal lavage sIgA titers were seen in non-coated liposomes followed by coated ones. The serum IgG titers (2nd bleeding) in animals immunized by both kinds of liposome were similar (P > 0.05), and were lower than the TT solution group (P < 0.05). Immunization by i.m. injection of TT solution resulted in the lowest sIgA and highest IgG titers (P < 0.05) compared with liposomal groups.The results were indicative of good potential of negatively charged liposomes in the induction of mucosal immunity. Coating of liposomes by chitosan, failed to increase both the residence time of liposomes in nasal cavity and systemic responses. Conversely, coated liposomes could not induce the mucosal responses as efficiently as non-coated liposomes. It seems that the coating of liposomes affected their interaction potential with nasal associated lymphoid tissue cells.  相似文献   

12.
Different animal models are used to evaluate the process of epileptogenesis. In this investigation the kindling model of epilepsy was used. The epileptic focus was induced in Chinchilla rabbits by stimulation of the hippocampus with electric stimuli. We presumed that the extracts of Ginkgo biloba affect the formation of kindling epilepsy. Bioelectric activity of the brain was registered throughout the development of kindling with and without standardized extracts from dried ginkgo leaves (EGb 761). For each animal the following has been determined: the values of the minimum current strength necessary for the origination of threshold after-discharge (AD) - discharges appearing after the cessation of stimulation; duration of the threshold AD; number of stimulations necessary for the origination of full kindling; time latency for the development of full kindling; number of spontaneous epileptogenic discharges manifested in EEG two days following the formation of full kindling during 60-minute registration. The results show that the process of epileptogenesis was influenced by EGb 761. It has been established that if the animals received EGb 761, significantly weaker minimum current strength was necessary for the development of the epileptogenic focus and the AD were longer, while the number of necessary electrostimulations for the appearance of full kindling was less and the latency was shorter.  相似文献   

13.
The present study was aimed at developing safe and effective bioadhesive gelling systems of ketorolac tromethamine, a potent non-narcotic analgesic with moderate anti-inflammatory activity for nasal systemic delivery. Chitosan and pectin based gelling systems were prepared with variables like polymer concentration and type. These systems were characterized in terms of their physical properties, in vitro bioadhesion, in vitro drug release and long-term stability. The anti-inflammatory activity and mucosal irritancy of selected gels were also evaluated in rats and these results were compared with per oral, intraperitoneal and nasal solution administration of ketorolac tromethamine. All the prepared formulations gelled immediately at the nasal mucosal pH and showed longer contact time. Addition of hydroxypropyl methylcellulose (HPMC) in both chitosan and pectin based gelling systems increased the viscosity and gel strength. All the formulated gels exhibited pseudoplastic rheology and diffusion-controlled drug release. The results from stability studies revealed that the prepared thermogels showed marginal decrease in viscosity but at the same time, no significant difference in drug content, and in vitro release characteristics were observed before and after accelerated studies. The developed gelling systems produced only mild to negligible irritant effect to nasal mucosae as compared to control group.  相似文献   

14.
The aim of the reported study was to optimize the extraction process for ganoderma triterpenes and to investigate the in vivo inhibitory effect of ganoderma triterpenes on the genesis and progression of oral cancer. Single-factor and orthogonal methods were used to investigate the effects of extraction solvent, solvent amount, extraction time, extraction temperature, and number of extractions, on the extraction rate for ganoderma triterpenes. A golden hamster model with cheek pouch dynamic canceration was established to receive oral treatment of ganoderma triterpenes water solution. Animals were continuously monitored, oral tissue samples were collected for histopathologic examination, and changes in the expression of VEGF (vascular endothelial growth factor) and Caspase-3 were detected by immunohistochemical methods. Optimization of the experimental conditions allowed the identification of the optimal extraction conditions: 90% ethanol as the extraction solvent, a solvent amount by the liquid-material ratio of 35 mL/g, extraction time of 2 h and extraction temperature of 80 °C. Under these conditions, the average extraction rate of ganoderma triterpenes was 1.09%. Tests in golden hamsters showed that compared with the model group during the same period, animals in the treatment group had better conditions, constantly larger number of normal cases shown by histopathologic results (P < 0.01), and consistently smaller numbers of cases with paraplasm (P < 0.05). Immunohistochemical results showed that compared with the model group, the treatment group had significantly lower (P < 0.05) rates of positive VEGF expression in the normal state, simple epithelial hyperplasia, epithelial dysplasia or squamous cell carcinoma disease stages. Caspase-3 expression showed a tendency toward a gradual increase with the worsening of disease severity in each group. Compared with the model group, the treatment group had significantly lower (P < 0.05) rates of positive Caspase-3 in the normal state, simple epithelial hyperplasia, epithelial dysplasia or squamous cell carcinoma disease grades. Using the optimized extraction process, ganoderma triterpenes could be extracted with high efficiency, and the results of animal tests showed inhibitory effects of ganoderma triterpenes on oral mucosa cancer.  相似文献   

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17.
Due to their benthic filter-feeding habits and high bioaccumulation potential of metals and organic compounds, bivalve molluscs have been widely used in studies in the field and laboratory to assess the toxic effects of several compounds discharged in rivers, oceans and estuaries. However, most ecotoxicological studies use invasive exotic species, while the response of native species is poorly known. The Brazilian endemic species Diplodon expansus occurs in rivers near areas of intense agricultural activity, and atrazine is currently one of the main residues of pesticides found in water bodies of the Brazilian territory. This study was aimed at examining the toxicity of different atrazine concentrations to a Brazilian native mollusc by analysing the histology, histochemistry and ultrastructure of its gill filaments. The cells that comprise the frontal and intermediary regions of gill filaments were the most affected by the herbicide and responses associated with damage and protection were observed. The response of tissues and cells were dose-dependent. Higher concentrations of herbicide caused more severe alterations in large areas of the gills. The persistence of the alterations observed might result in severe functional problems in the gills of these animals, negatively affecting their performance and health.  相似文献   

18.
The hydrogen desorption (or decomposition) reaction of NaAlH4 is expressed as , and its desorption rate is accelerated by mixing metal chloride catalysts (e.g., TiCl3). This catalytic effect of metal chlorides, MCln, is theoretically estimated in a quantitative way using atomization energy concept. The atomization energies, ΔEM for metal ion and ΔECl for chloride ion in various metal chlorides are evaluated using the energy density analysis of the total energy. It is shown that the hydrogen desorption reaction rate increases with increasing n × ΔEM values of metal chlorides. This indicates that the metal ion in MCln interacts mainly with hydrogen or [AlH4]? complex anion in NaAlH4. To confirm this calculated result, experiments are performed using NaAlH4 mixed with Ti‐based catalysts. The hydrogen desorption rate is enhanced in the order, TiCl3 > TiO2 > Ti metal nanopowder, indicating that the Ti ions in TiCl3 or TiO2 work to promote the catalytic reaction more effectively than the neutral Ti atoms in Ti metal nanopowder. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011  相似文献   

19.
Polyamine distribution in the rat intestinal mucosa   总被引:1,自引:0,他引:1  
As the first step in a study of mucosal polyamine metabolism during intestinal adaptation, we have measured mucosal polyamine concentrations at different sites along the normal rat intestine. Putrescine, spermidine, spermine and cadaverine were measured by spectrofluorometric analysis after thin-layer chromatography of their dansylated derivatives. Spermidine was present in the largest amounts at each of the sampling sites. The ratio of the concentration of spermidine to that of spermine paralleled the established pattern of cellular proliferation in the normal intestine as did the putrescine concentration (nmol per 10 cm) which decreased from duodenum to colon. These results provide the essential background to an assessment of the role of polyamines in the intestinal adaptive response.  相似文献   

20.
Calorimetry was applied to follow the hydration in the Portland cement–dolomite–limestone mixtures. In the experiments the limestone additive of various fineness (standard component of various common cements), as well as the dolomite additive (not a standard component) were used. The rate of hydration versus time for common cements reflects the proper setting and early hardening during the first days after mixing with water (two or three peaks and the induction period between them). The aim of measurements presented in this work was to show the course of heat evolution curve and the heat evolved values, equivalent to the acceleration/retardation of hydration, in case of the pastes produced from Portland cement and the carbonate additives mixed in variable proportions, as well as to verify the results by other methods. The rate of heat evolution accompanying cement paste hydration, total heat evolved, conductivity of hydrating suspension and rheological (flow) properties versus time are modified by the fine grained carbonate additives. This is due to the hypothetical nucleating effect of limestone and dolomite.  相似文献   

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