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1.

Purpose

To test the hypothesis of surface displacement as the underlying mechanism for IgG stabilization by polysorbates and HP??CD against surface-induced aggregation.

Methods

Adsorption/desorption-kinetics of IgG-polysorbate 80/-HP??CD were monitored. Maximum bubble pressure method was used for processes within seconds from surface formation. Profile analysis tensiometry was applied over long periods and to assess surface rheologic properties. Additionally, the kinetics of adsorption, desorption and surface displacement was followed by a double-capillary setup of the profile analysis tensiometer, allowing drop bulk exchange.

Results

Weak surface activity for HP??CD vs. much higher surface activity for polysorbate 80 was shown. Protein-displacement when exceeding a polysorbate 80 concentration close to the CMC and a lack of protein displacement for HP??CD was observed. The drop bulk exchange experiments show IgG displacement by polysorbate 80 independent of the adsorption order. In contrast, HP??CD coexists with IgG at the air-water interface when the surface layer is built from a mixed IgG-HP??CD-solution. Incorporation of HP??CD in a preformed IgG-surface-layer does not occur.

Conclusions

The results confirm surface displacement as the stabilization mechanism of polysorbate 80, but refute the frequently held opinion, that HP??CD stabilizes proteins against aggregation at the air-water interface in a manner comparable to non-ionic surfactants.  相似文献   

2.
PURPOSE: To compare the systemic delivery of deslorelin following intratracheal administration of different deslorelin formulations. The formulations included dry powders of deslorelin, large-porous deslorelin-poly(lactide-co-glycolide) (PLGA) particles, and small conventional deslorelin-PLGA particles. Also, solution formulations of deslorelin and deslorelin-hydroxy-propyl-beta-cyclodextrin (HPbetaCD) complexes were tested. METHODS: Dry powders of deslorelin, large-porous (mean diameter, 13.8 microm; density, 0.082 g/cc), and small conventional (mean diameter, 2.2 microm; density, 0.7 g/cc) deslorelin-PLGA particles and solutions of deslorelin with or without HPbetaCD were administered intratracheally to Sprague-Dawley rats. Blood samples were collected at 3 h, 1, 3, and 7 days postdosing, and plasma deslorelin concentrations were determined using enzyme immunoassay. At the end of 7 days, lungs were isolated, and bronchoalveolar lavage fluid was collected and analyzed for deslorelin. RESULTS: At the end of 7 days, deslorelin plasma concentrations in the large-porous deslorelin-PLGA particle group were 120-fold and 2.5-fold higher compared to deslorelin powder and small conventional deslorelin-PLGA particles, respectively. Co-administration of HPbetaCD resulted in 2-, 3-, and 3-fold higher plasma deslorelin concentrations at 3 h, 1 and 3 days, respectively, compared to deslorelin solution. On day 7, deslorelin concentrations in bronchoalveolar lavage fluid as well as plasma were in the order: large porous particles > small conventional particles > deslorelin-HPbetaCD solution > deslorelin powder > deslorelin solution. CONCLUSIONS: Large-porous deslorelin PLGA particles can sustain deslorelin delivery via the deep lungs. Co-administration of HPbetaCD enhances the systemic delivery of deslorelin. The pulmonary route is useful as a noninvasive alternative for the systemic delivery of deslorelin.  相似文献   

3.
4.
RAGE (receptor for advanced glycation end products) is a multiligand receptor on the cell surface. Ligand-RAGE interactions activate several signal transduction pathways that propagate cellular oxidative stress and inflammatory response. RAGE expressed on the CD4+ T cells has been identified as a central transduction receptor which affects the activation, proliferation, migration and differentiation of the cells. In addition, blockade of RAGE suppressed the development of multiple immune-related disorders mediated by CD4+ T cells. These studies highlight the importance of RAGE and its ligands for CD4+ T cells. This article briefly reviews the role of RAGE and its ligands on the proliferation, migration and differentiation of CD4+ T cells and summarizes the related research progress.  相似文献   

5.
Little is known about the regulatory T cells (Tregs) in the peripheral blood after surgery of non-small cell lung cancer (NSCLC) patients. In this study, we investigated whether CD4+CD25+FOXP3 + and CD8+CD28 − regulatory T cells are decreased in the peripheral blood of NSCLC patients undergoing surgery. The study group (n = 49) comprised NSCLC, and the control group (n = 24) consisted of age- and sex-matched nonmalignant diseases. The prevalence of CD4+CD25+FOXP3 + and CD8+CD28 − Tregs was analyzed using flow cytometry. The study group showed significantly higher percentage of CD4+CD25+FOXP3 + and CD8+CD28 − Tregs than control. The percentage of CD4+CD25+FOXP3 + and CD8+CD28 − Tregs increased with tumor stage. One way ANOVA test shows the significant differences between all subgroups. LSD test shows that there was a statistical significance between each of the two subgroups except stage II in CD4+CD25+FOXP3 + Tregs and control vs. each stage, stage I vs. stage III, and stage IV in CD8+CD28 − Tregs. There is no significant difference among stages II, III, and IV in CD8+CD28 − Tregs. No differences were found between squamous carcinoma and adenocarcinoma. These levels were dropped significantly after operation. Furthermore postoperative Treg percentage in the early stages (stage I and stage II) was not statistically different from that of controls. Postoperative Treg percentage in advanced stage (III + IV) remained above the values shown by controls. Our findings indicate that the percentage of CD4+CD25+FOXP3 + and CD8+CD28 − Tregs correlated with the pathological stage in NSCLC and tumor burden.  相似文献   

6.
Paeoniflorin has been demonstrated to exert anti-inflammatory and immunomodulatory effects in the animal study. The purpose of the present study was to investigate the effect of paeoniflorin on the recombinant human interleukin-1β (rhIL-1β)-stimulated monocytes from the peripheral blood of healthy adults in vitro. Monocytes, collected from the peripheral blood of healthy adults by the Ficoll density gradient centrifugation, were co-cultured with rhIL-1β to imitate inflammatory circumstance in vitro. After exposure of rhIL-1β (0.01, 0.1, 1, 10μg·l(-1)) for 24h or rhIL-1β (1μg·l(-1)) for different time periods (3, 6, 12, 24h), we observed that the phagocytic function and the production of TNF-α and PGE(2) with monocytes were promoted significantly by rhIL-1β. MTT assay demonstrated that paeoniflorin (concentrations ranged from 10(-4)mol·l(-1) to 10(-9)mol·l(-1)) showed low cytotoxicity with rhIL-1β-stimulated monocytes. Paeoniflorin (10(-9), 10(-8), 10(-7), 10(-6), 10(-5)mol·l(-1)) significantly suppressed phagocytic function of rhIL-1β-induced monocytes (P<0.05), and decreased the levels of TNF-α and PGE(2) production in a concentration-dependent manner (r=-0.820 and r=-0.836, respectively). The flow cytometry analysis showed that the stimulation of rhIL-1β significantly increased the mean fluorescence rates of HLA-DR in a time-dependent manner (r=0.977). Administration of paeoniflorin (10(-9), 10(-8), 10(-7), 10(-6), 10(-5)mol·l(-1)) significantly inhibited the mean fluorescence rates of HLA-DR and CD80 with rhIL-1β-stimulated monocytes (P<0.05). These results indicated that paeoniflorin might inhibit activation of human peripheral blood monocytes stimulated by rhIL-1β, suppress function of monocytes, and down-regulate expression of HLA-DR and CD80, suggesting that paeoniflorin might alleviate the chronic inflammation by inhibiting human monocytes.  相似文献   

7.

Purpose

The objective of present study was to increase solubility and dissolution performance of a poorly water soluble antidiabetic drug, Nateglinide (NAT), through formation of inclusion complexes with hydroxypropyl-beta-cyclodextrin (HP–β–CD). The effect of L-arginine (ARG), an amino acid, on the complexation efficiency and solubility enhancing power of HP–β–CD was investigated by preparing ternary inclusion complexes.

Methods

The binary and ternary inclusion complexes were prepared by physical mixing, kneading, co-evaporation, and spray drying methods containing NAT, HP–β–CD, and ARG. The complexes were characterized by FTIR, DSC, PXRD, and 1H–NMR. Molecular modeling study revealed that introduction of ternary agent ARG have improved the interactions of NAT and HP–β–CD.

Results

The complex prepared by spray drying method showed the highest increase in solubility and dissolution rate compared to other methods. Molecular docking study revealed that ARG interactions plays an essential role in increasing the stability and solubility of the complex.

Conclusions

The present study demonstrated increase in solubility and dissolution of NAT. Hence, ternary complexes of NAT can be used as an efficient tool for the delivery of insoluble drug, NAT.
  相似文献   

8.
Journal of Neuroimmune Pharmacology - In this study cannabidiol (CBD) was administered orally to determine its effects and mechanisms in the experimental autoimmune encephalomyelitis (EAE) model of...  相似文献   

9.
Factor VIII (FVIII) is an important coagulation cofactor and its deficiency causes Hemophilia A, a bleeding disorder. Replacement therapy using recombinant FVIII is currently the first line of therapy for Hemophilia A, but the development of neutralizing antibody is a major clinical complication for this therapy. Recently, it has been shown that FVIII associated with phosphatidylinositol (PI)-containing lipidic nanoparticles reduced development of neutralizing antibodies in Hemophilia A mice (Peng A, Straubinger RM, Balu-Iyer SV. 2010. AAPS J 12(3):473-481). Here, we investigated the underlying mechanism of this reduction in antibody response in culturing conditions. In vitro, PI interfered with the processing of FVIII by cultured dendritic cells (DC), resulting in a reduction in the upregulation of phenotypic costimulatory signal CD40. Furthermore, PI increased secretion of regulatory cytokines Transforming Growth Factor β1 and Interleukin 10 (IL-10) but reduced the secretion of proinflammatory cytokines IL-6 and IL-17. The data suggest that PI reduces immunogenicity of FVIII by modulating DC maturation and inducing secretion of regulatory cytokines.  相似文献   

10.

Background and Purpose

α-Galactosylceramide (α-GalCer), a pleiotropic immunomodulator with therapeutic potential in neoplastic, autoimmune and allergic diseases, activates invariant natural killer T-cells throughCD1-restricted receptors for α-GalCer on antigen-presenting cells, inducing cytokine secretion. However the haemopoietic effects of α-GalCer remain little explored.

Experimental Approach

α-GalCer-induced modulation of eosinophil production in IL-5-stimulated bone marrow cultures was examined in wild-type (BALB/c, C57BL/6) mice and their mutants lacking CD1, inducible NOS (iNOS), CD95 and IFN-γ, along with the effects of lymphocytes; IFN-γ; caspase and iNOS inhibitors; non-steroidal anti-inflammatory drugs (NSAIDs) and LTD4; and dexamethasone.

Key Results

α-GalCer (10−6–10−8M) suppressed IL-5-stimulated eosinopoiesis by inducing apoptosis. α-GalCer pretreatment in vivo (100 μg·kg−1, i.v.) suppressed colony formation by GM-CSF-stimulated bone marrow progenitors in semi-solid cultures. α-GalCer and dexamethasone synergistically promoted eosinophil maturation. Suppression of eosinophil production by α-GalCer was prevented by aminoguanidine and was undetectable in bone marrow lacking iNOS, CD95, CD28; or CD1d. Separation on Percoll gradients and depletion of CD3+ cells made bone marrow precursors unresponsive to α-GalCer. Responsiveness was restored with splenic lymphocytes. Experiments with (i) IFN-γ-deficient bone marrow, alone or co-cultured with spleen T-cells from wild-type, but not from CD1d-deficient, donors; (ii) IFN-γ neutralization; and (iii) recombinant IFN-γ, showed that these effects of α-GalCer were mediated by IFN-γ. Effects of α-GalCer on eosinophil production were blocked by LTD4 and NSAIDs.

Conclusions and Implications

α-GalCer activation of IFN-γ-secreting, CD1d-restricted lymphocytes induced iNOS-CD95-dependent apoptosis in developing eosinophils. This pathway is initiated by endogenous regulatory lymphocytes, antagonised by LTD4, NSAIDs and aminoguanidine, and modified by dexamethasone.  相似文献   

11.
《Toxicology in vitro》2015,29(8):1474-1481
Immunotoxicity studies of nanoparticles on T cells addressed their effects on activation by T antigen receptor, but have neglected the regulation of proliferation by IL-2. In this study, the IL-2-dependent T lymphoblastoid WE17/10 cell line was used to compare silver (Ag-NPs) and fullerene (C60-NPs) nanoparticles’ toxicity and evaluate whether these NPs could interfere with IL-2-dependent proliferation. Results have shown that Ag-NPs are more toxic, as they reduced cell viability at the highest concentration tested (100 μg/ml), while C60-NPs have shown good biocompatibility. Characterization of NP suspensions by dynamic light scattering measured large aggregates for C60-NPs, whereas Ag-NPs were relatively stable and well dispersed. This translated into a much larger uptake of Ag-NPs compared to C60-NPs, as measured by flow cytometry. Proliferation measurements by CFSE following 72 h incubation have shown that Ag-NPs decrease cell proliferation and C60-NPs slightly increase proliferation. CD25 expression was unchanged following exposure to C60-NPs, but was significantly increased by Ag-NPs’ presence for short and long-term incubations. Analyses of three key signaling proteins activated by IL-2 receptor (Stat5, JNK and ERK1/2) by western immunoblotting have shown no effects from either NPs on Stat5 and JNK phosphorylation. ERK1/2 was slightly activated following a short exposure to Ag-NPs, while C60-NPs had no effect. Our results show that C60-NPs have good biocompatibility and do not interfere with IL-2-dependent proliferation. A deeper investigation would be needed for the case of Ag-NPs, since the mechanism of their action is still unclear.  相似文献   

12.
13.
Objective: To evaluate the safety and efficacy of rapid rituximab infusion (RRI) plus chemotherapy in patients with CD20+ non-Hodgkin’s lymphoma (NHL).

Research design and methods: A total of 177 patients received 4 – 6 cycles of rituximab-based chemotherapy. The first cycle was given with standard schedule. In the second and subsequent cycles, RRI was initiated. Rituximab was administered as 20% of the dose infused in the first 30 min and the remaining 80% was given over 60 min. Benadryl and dexamethasone were given before infusions. Vital signs were measured at baseline and during infusion.

Results: In the first cycle, 48 patients experienced grade I – II infusion reactions and two patients showed grade III – IV infusion reactions. Six patients experienced infusion reactions during RRI. Two patients showed grade III infusion reactions to RRI and dropped out of the study. With a median follow up of 37.5 months, the 3-year overall survival and progression-free survival rates of the whole cohort were 93.1 and 81.1%, respectively.

Conclusions: Our preliminary observations suggested that RRI may be safe and feasible for patients with CD20+ NHL.  相似文献   


14.
Ethylcellulose in combination with water-soluble additives has been used in the development of microporous membrane-coated dosage forms. In the present study, application of three types of water-soluble additives, namely polyethylene glycols (PEG 400, 3350, and 8000), maltodextrins (Maltrin M150, M100, and M040 in the order of lower to higher average polymer size and molecular weight; dextrose equivalence 16.9, 11.1, and 4.8, respectively), and xylitol, as porosity modifiers in the films of a commercially available aqueous ethylcellulose dispersion (Surelease/E-7-7060 plasticized with glyceryl tricaprylate/caprate) was investigated. The effect of type and level of these additives on drug release characteristics and surface and mechanical properties of the polymeric films was studied. Each additive was incorporated at 20 and 30% levels in the polymeric dispersion based on its solids content. Ibuprofen tablets were coated using the polymeric dispersion with and without additive at 3% w/w coat level in a fluid-bed equipment. The coated tablets were evaluated for their drug release rate, coat reflectivity (gloss), Brinell hardness, and elastic modulus. Differential scanning calorimetric analysis of the films was performed to determine the physico-chemical changes in the applied film-coats. The rate of drug release, hence film porosity, was observed to be dependent on the type and level of the additive added. The molecular weight of the additive and its concentration in the polymeric dispersion had significant influence on the rate of drug release, hardness, and elasticity of the film-coats.  相似文献   

15.
S21Possibleinvolvementofhereditaryfactors intheriskmodulationofarseniasisintwoethnic clansexposedtoindoorcombustionofhigharse niccoal LINGuo Fang1,DUHui2,CHENJi Gang3,LU Hong Chao2,GUOWei Chao1,ZHANGXin Jiang4,SHENJian Hua1(1.ShanghaiInstituteforBiologicalSciences,Institute ofPlantPhysiologyandEcology,ChineseAcademyof Sciences,Shanghai200032,China;2.Prefecture CenterforDiseasePreventionandControl,Guiyang562400,China;3.MunicipalCenterforDiseasePre ventionandControl,Shang…  相似文献   

16.
Summary In eight healthy volunteers the bioavailability of -acetyldigoxin solution and tablets was measured after single and multiple doses. Plasma and urine data were used to calculate bioavailability by four different methods. The differences obtained and the interindividual variations suggested that different and independent methods should be employed to assess absolute and true bioavailability. There was no significant difference between the regimens and both preparations had similar bioavailability; mean values (± SD) for the solution were 68.3 ± 8.7 % (single dose) and 68.6±5.9 % (multiple doses), and for the tablets 72.8±7.5 % and 66.1±6.0 %, respectively. For routine measurements, single dose studies with plasma and urine sampling for 24 hours and 48 hours, respectively, were an accurate and practicable procedure.  相似文献   

17.
S11StudiesontoxicityofChinesemedicines anddecreasedvirulencethroughthecompatibili tyofherbalingredients LIPeng Tao(CST)(BeijingUniversityofTraditionalChineseMedicine,Beijing100029,China)Beginningfromthereportoftherenalinjuryin ducedbyaristolochicacid,thepoisonoussideeffects ofChinesemedicineshaveattractedmoreandmoreat tentions,whichhaveproducedhugeinfluenceontheprogressoftraditionalChinesemedicines.Itbecomesa vitallyimportantissuetounderstandanduseChinese medicinescorrectly.Thetoxicity…  相似文献   

18.
A series of β-amino carbonyl compounds containing coumarin (4ah) and benzofuran (6ai) moieties was synthesized by a three component Mannich reaction of 3-acetyl-2H-chromen-2-one (1) or 1-(1-benzofuran-2-yl) ethanone (5) with p-substituted aromatic aldehydes (2ag) and aromatic amines (3ab) in the presence of cerric ammonium nitrate as a catalyst. The newly synthesized compounds were screened for antimicrobial and antioxidant activities. Compounds 4b, 4e, 4f, 6f, 6g, and 6i showed microbial inhibition with minimal inhibition concentration ranging between 0.040 and 0.500 mg/mL, compounds 4b, 4c, 6c, 6e, and 6i showed promising free radical scavenging activity and compounds 4b, 4f, 6c, 6d, and 6h showed good chelating ability with Fe2+ ions. The synthesized compounds were studied for docking on the enzyme, glucosamine-6-phosphate synthase to predict the binding affinity and orientation at the active site of the receptor.  相似文献   

19.
LinZL 《中国药学》1994,3(2):173-175
PharmacokineticsandPharmacodynamicsofNitrendipinePharmacokineticsandPharmacodynamicsofNitrendipineMarster'sDegreeZhen-LiLinSu...  相似文献   

20.
We previously demonstrated an age-related decrease in receptor for activated C-kinase (RACK-1) expression and functional deficit in Langerhans cells’ responsiveness. This defect specifically involves the translocation of protein kinase C (PKC)-β. The purpose of this study was to investigate the role of RACK-1 and PKC-β in chemical allergen-induced CD86 expression and IL-8 release in the human promyelocytic cell line THP-1 and primary human dendritic cells (DC). Dinitrochlorobenzene, p-phenylenediamine and diethyl maleate were used as contact allergens. The selective cell-permeable inhibitor of PKC-β and the broad PKC inhibitor GF109203X completely prevented chemical allergen- or lipopolysaccharide (LPS)-induced CD86 expression and significantly modulated IL-8 release (50 % reduction). The selective cell-permeable inhibitor of PKC-ε (also known to bind to RACK-1) failed to modulate allergen- or LPS-induced CD86 expression or allergen-induced IL-8 release, while modulating LPS-induced IL-8 release. The use of a RACK-1 pseudosubstrate, which directly activates PKC-β, resulted in dose-related increase in CD86 expression and IL-8 release. Similar results were obtained with human DC, confirming the relevance of results obtained in THP-1 cells. Overall, our findings demonstrate the role of PKC-β and RACK-1 in allergen-induced CD86 expression and IL-8 production, supporting a central role of PKC-β in the initiation of chemical allergen-induced DC activation.  相似文献   

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