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1.
A rapid selection system was used to screen Glycyrrhiza uralensis plants containing high concentrations of glycyrrhizin (GC) by Eastern blotting using anti-GC monoclonal antibody (MAb). Chromatographic fingerprinting by Eastern blotting correlated with the GC concentration analyzed by enzyme-linked immunosorbent assay (ELISA). The roots of wild G. uralensis growing in Mongolia were analyzed by Eastern blotting to identify plants containing high concentrations of GC, and the GC concentration was confirmed by ELISA. G. uralensis plants cultivated in the greenhouse were also analyzed in the same manner. GC concentrations in wild G. uralensis roots and cultivated plants varied widely: between 0.06 and 9.36 percent dry weight (dw%). To confirm the homogeneity of GC concentrations in the cultivated plants, we monitored GC concentrations in the plants over 2 years. Although GC concentrations changed in two plants, they remained comparatively constant in the other five plants, suggesting that GC concentrations are genetically determined. To identify high GC-producing plants, 1025 plants were analyzed, and the highest concentration of GC was 5.36 dw%.  相似文献   

2.

Purpose

To develop a live oral delivery system of Glucagon like peptide-1 (GLP-1), for the treatment of Type-2 Diabetes.

Methods

LL-pUBGLP-1, a recombinant Lactococcus lactis (L. lactis)) transformed with a plasmid vector encoding GLP-1 cDNA was constructed and was used as a delivery system. Secretion of rGLP-1 from LL-pUBGLP-1 was characterized by ELISA. The bioactivity of the rGLP-1 was examined for its insulinotropic activity on HIT-T15 cells. Transport of rGLP-1 across MDCK cell monolayer when delivered by LL-pUBGLP-1 was studied. The therapeutic effect of LL-pUBGLP-1 after oral administration was investigated in ZDF rats.

Results

DNA sequencing and ELISA confirmed the successful construction of the LL-pUBGLP-1 and secretion of the active form of rGLP-1. In vitro insulinotropic studies demonstrated that LL-pUBGLP-1 could significantly (p?GLP-1 transport rate across the MDCK cell monolayer was increased by eight times (p?p?0-11h (2.5 times, p?Conclusion The present study demonstrates that L. lactis when genetically modified with a recombinant plasmid can be used for the oral delivery of GLP-1.  相似文献   

3.
4.

Purpose

The purpose of this study was to investigate the effect of locally delivered pancreatic islet with liposomal clodronate (Clodrosome®) as an immunoprotection agent for the treatment of type 1 diabetes.

Method

The bio-distribution of liposomal clodronate in matrigel was checked by imaging analyzer. To verify the therapeutic efficacy of locally delivered islet with liposomal clodronate using injectable hydrogel, four groups of islet transplanted mice (n?=?6 in each group) were prepared: 1) the islet group, 2) the islet-Clodrosome group, 3) the islet-Matrigel group, and 4) the islet-Matrigel-Clodrosome group. Immune cell migration and activation, and pro-inflammatory cytokine secretion was evaluated by immunohistochemistry staining and ELISA assay.

Results

Cy5.5 labeled liposomes remained in the matrigel for over 7 days. The median survival time of transplanted islets (Islet-Matrigel-Clodrosome group) was significantly increased (>60 days), compared to other groups. Locally delivered liposomal clodronate in matrigel effectively inhibited the activation of macrophages, immune cell migration and activation, and pro-inflammatory cytokine secretion from macrophages.

Conclusions

Locally co-delivered pancreatic islets and liposomal clodronate using injectable hydrogel effectively cured type 1 diabetes. Especially, the inhibition of macrophage attack in the early stage after local delivery of islets was very important for the successful long-term survival of delivered islets.  相似文献   

5.
In this study, we evaluated the effects of Di-(2-ethyhexyl) phthalates (DEHP) on cell cycle. We cultured human endometiral cancer cell lines (ECC-1) and then incubated them for 48 h with 50 μM of DEHP. We perfomed the microarray, the quantitative real-time polymerase chain reaction (qRT-PCR) and the FACS analysis. On microarray results, genes associated with functional classification of cell cycle, oocyst meiosis and progesterone mediated oocyte maturation showed significant changes. Among those changed genes, CCNB1 and CCNB2 are involved in the progesterone-mediated oocyte maturation, and CDC2 (CDK1) involved in the oocyte meiosis. The apoptosis and necrosis were both increased at a concentration of DEHP of < 50 μM, but the apoptosis was decreased at a concentration of DEHP of >100 μM. In conclusion, our results indicate that endometriosis and endometrial cancer, abnormal ovulation might occur after DEHP exposure.  相似文献   

6.

Rationale

Mitochondrial complex I dysfunction and alterations in DNA methylation levels are consistently reported in bipolar disorder (BD) and are regulated by lithium. One of the mechanisms by which lithium may exert its effects in BD is by improving mitochondrial complex I function. Therefore, we examined whether complex I dysfunction induces methylation and hydroxymethylation of DNA and whether lithium alters these effects in rat primary cortical neurons.

Methods

Rotenone was used to induce mitochondrial complex I dysfunction. Cell viability was measured by MTT assay, and ATP levels were assessed by Cell-Titer-Glo®. Complex I activity was measured using an ELISA-based assay. Apoptosis, DNA methylation, and hydroxymethylation levels were measured by immunocytochemistry.

Results

Rotenone decreased complex I activity and ATP production, but increased cell death and apoptosis. Rotenone treatment increased levels of 5-methylcytosine (5mc) and hydroxymethylcytosine (5hmc), suggesting a possible association between complex I dysfunction and DNA alterations. Lithium prevented rotenone-induced changes in mitochondrial complex I function, cell death and changes to DNA methylation and hydroxymethylation.

Conclusions

These findings suggest that decreased mitochondrial complex I activity may increase DNA methylation and hydroxymethylation in rat primary cortical neurons and that lithium may prevent these effects.  相似文献   

7.

Rationale

Monoamine reuptake inhibitors can stimulate expression of brain-derived neurotrophic factor (BDNF) and alter long-term potentiation (LTP), a widely used model for the synaptic mechanisms that underlie memory formation. BDNF expression is upregulated during LTP, and BDNF in turn positively modulates LTP. Previously, we found that treatment with venlafaxine, a serotonin and norepinephrine reuptake inhibitor (SNRI), but not citalopram, a selective serotonin reuptake inhibitor (SSRI), reduced LTP in hippocampal area CA1 without changing hippocampal BDNF protein expression.

Objectives

We tested the hypothesis that combined serotonin and norepinephrine reuptake inhibition is necessary for LTP impairment, and we reexamined the potential role of BDNF by testing for region-specific changes in areas CA1, CA3, and dentate gyrus. We also tested whether early events in the LTP signaling pathway were altered to impair LTP.

Methods

Animals were treated for 21 days with venlafaxine, imipramine, fluoxetine, or maprotiline. In vitro hippocampal slices were used for electrophysiological measurements. Protein expression was measured by enzyme-linked immunosorbent assay (ELISA) and Western blotting.

Results

LTP was impaired only following treatment with combined serotonin and norepinephrine reuptake inhibitors (venlafaxine, imipramine) but not with selective serotonin (fluoxetine) or norepinephrine (maprotiline) reuptake inhibitors. BDNF protein expression was not altered by venlafaxine or imipramine treatment, nor were postsynaptic depolarization during LTP inducing stimulation or synaptic membrane NMDA receptor subunit expression affected.

Conclusions

LTP is impaired by chronic treatment with antidepressant that inhibit both serotonin and norepinephrine reuptake; this impairment results from changes that are downstream of postsynaptic depolarization and calcium influx.  相似文献   

8.
Ecstasy is the popular name of the abuse drug 3,4-methylenedioxymethamphetamine (MDMA) that decreases immunity in animals. The mechanisms that generate such alterations are still controversial. Seven independent pharmacological approaches were performed in mice to identify the possible mechanisms underlying the decrease of neutrophil activity induced by MDMA and the possible effects of MDMA on host resistance to Listeria monocytogenes. Our data showed that MDMA (10 mg kg?1) administration decreases NFκB expression in circulating neutrophils. Metyrapone or RU-486 administration prior to MDMA treatment abrogated MDMA effects on neutrophil activity and NFκB expression, while 6-OHDA or ICI-118,551 administration did not. As MDMA treatment increased the plasmatic levels of adrenaline and noradrenaline, propranolol pre-treatment effects were also evaluated. Propranolol suppressed both MDMA-induced increase in corticosterone serum levels and its effects on neutrophil activity. In a L. monocytogenes experimental infection context, we showed that MDMA: induced myelosuppression by decreasing granulocyte-macrophage hematopoietic progenitors (CFU-GM) in the bone marrow but increased CFU-GM in the spleen; decreased circulating leukocytes and bone marrow cellularity and increased spleen cellularity; decreased pro-inflammatory cytokine (IL-12p70, TNF, IFN-γ, IL-6) and chemokine (MCP-1) production 24 h after the infection; increased the production of pro-inflammatory cytokines and chemokines 72 h after infection and decreased IL-10 levels at all time points analyzed. It was proposed that MDMA immunosuppressive effects on neutrophil activity and host resistance to L monocytogenes rely on NFκB signaling, being mediated by HPA axis activity and corticosterone.  相似文献   

9.
10.

Purpose

For building functional vasculature, controlled delivery of fibroblast growth factor-9 (FGF9) from electrospun fibers is an appealing strategy to overcome challenges associated with its short half-life. FGF9 sustained delivery could potentially drive muscularization of angiogenic sprouts and help regenerate stable functional neovasculature in ischemic vascular disease patients.

Methods

Electrospinning parameters of FGF9-loaded poly(ester amide) (PEA) fibers have been optimized, using blend and emulsion electrospinning techniques. In vitro PEA matrix degradation, biocompatibility, FGF9 release kinetics, and bioactivity of the released FGF9 were evaluated. qPCR was employed to evaluate platelet-derived growth factor receptor-β (PDGFRβ) gene expression in NIH-3T3 fibroblasts, 10T1/2 cells, and human coronary artery smooth muscle cells cultured on PEA fibers at different FGF9 concentrations.

Results

Loaded PEA fibers exhibited controlled release of FGF9 over 28 days with limited burst effect while preserving FGF9 bioactivity. FGF9-loaded and unloaded electrospun fibers were found to support the proliferation of fibroblasts for five days even in serum-depleted conditions. Cells cultured on FGF9-supplemented PEA mats resulted in upregulation of PDGFRβ in concentration and cell type-dependent manner.

Conclusion

This study supports the premise of controlled delivery of FGF9 from PEA electrospun fibers for potential therapeutic angiogenesis applications.  相似文献   

11.

Purpose

To investigate the vaccine effect of a replication-defective recombinant adenovirus 5 (rAd5)-based nanocomplex with chitooligosaccharides (Oligo) and mannosylated polyethyleneimine-triethyleneglycol (mPEI) as adjuvants for human immunodeficiency virus (HIV) infection.

Methods

Physical characteristics were determined through detecting the size, zeta potential and morphology of Oligo-mPEI-rAd5 nanocomplex, and in vitro vaccine uptake and transduction efficiency were estimated. Nanocomplexes were then administered intranasally to Balb/c mice to evaluate in vivo rAd5 residence in nasal cavity and HIVgag-specific immune responses using cytotoxic T lymphocyte (CTL), intracellular cytokine staining (ICS) and ELISA assay.

Results

The mucoadhesivity of Oligo prolonged nasal residence time, while the dendritic cell (DC) specificity of mPEI improved vaccine uptake. These two adjuvants jointly enhanced transduction efficiency of rAd5. Oligo-mPEI-rAd5 nanocomplex elicited potent HIVgag-specific CTL response and increased IFN-γ positive CD8+T and IL-4 positive CD4+T cells, indicating high cellular immune responses. This vaccine candidate also led to strong humoral immune responses (IgG/IgG1/IgG2a) with balanced Th1/Th2 CD4+T cell activity. Moreover, mice nasally immunized with Oligo-mPEI-rAd5 showed higher levels of SIgA in nasal washes than did mice immunized with rAd5.

Conclusions

Intranasal delivery of Oligo-mPEI-rAd5 with a prime-boost regimen is a potential immunization for HIV infection, inducing HIVgag-specific cellular, humoral and mucosal immune responses.  相似文献   

12.
HIV-1 associated neurocognitive deficits are increasing in prevalence, although the neuronal basis for these deficits is unclear. HIV-1 Tg rats constitutively express 7 of 9 HIV-associated proteins, and may be useful for studying the neuropathological substrates of HIV-1 associated neurocognitive disorders (HAND). In this study, adult female HIV-1 Tg rats and F344 control rats had similar growth rates, estrous cyclicity and startle reflex inhibition to a visual prepulse stimulus. Medium spiny neurons (MSNs) in the nucleus accumbens (NAcc) were ballistically-labeled utilizing the indocarbocyanine dye DiI. The branching complexity of MSNs in the NAcc was significantly decreased in HIV-1 Tg rats, relative to controls; moreover, the shorter length and decreased volume of dendritic spines, but unchanged head diameter, in HIV-1 Tg rats suggested a reduction of longer spines and an increase in shorter, less projected spines, indicating a population shift to a more immature spine phenotype. Collectively, these results from HIV-1 Tg female rats indicated significant synaptodendritic alterations of MSNs in the NAcc occur as a consequence of chronic, low-level, exposure to HIV-1 associated proteins.  相似文献   

13.
31 topsoil samples were collected by grid method in Xiaodian sewage irrigation area, Taiyuan City, North of China. The concentrations of 16 kinds of polycyclic aromatic hydrocarbons (PAHs) were determined by gas chromatograph coupled with mass spectrum. Generally speaking, the distribution order of PAHs in the area is: those with five and six rings > those with four rings > those with two and three rings. Source apportionment shows a significant zonation of the source of PAHs: the civil coal pollution occurred in the north part, the local and far factory pollution happened in the middle area and the mixed pollution sources from coal and wood combustion, automotive emission, presented in the south area. The distribution of PAHs has a definite relationship with the sewage water flow and soil adsorption. The related coefficient between PAHs and physicochemical property showed there was a negative correlation between pH, silt, clay and PAHs while there was a positive correlation between total organic carbon, sand and PAHs.  相似文献   

14.

Rationale

We have recently shown that chronic exposure to 3,4-methylenedioxymethamphetamine (MDMA, “ecstasy”) of adolescent mice exacerbates dopamine neurotoxicity and neuroinflammatory effects elicited by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in the substantia nigra and striatum at adulthood.

Objectives

The present study investigated whether the amplification of MPTP effects by previous treatment with MDMA extends to the limbic and cortical regions and consequently affects cognitive performance.

Methods

Mice received MDMA (10 mg/kg, twice a day/twice a week) for 9 weeks, followed by MPTP (20 mg/kg?×?4 administrations), starting 2 weeks after MDMA discontinuation. Complement type 3 receptor (CD11b) and glial fibrillary acidic protein (GFAP) were evaluated by immunohistochemistry in both the hippocampus and the medial prefrontal cortex (mPFC) to measure microglia and astroglia activation. These neurochemical evaluations were paired with an assessment of cognitive performance by means of the novel object recognition (NOR) and spontaneous alternation tasks.

Results

MPTP administration to MDMA-pretreated mice elicited a stronger activation of CD11b and GFAP in both the hippocampus and the mPFC compared with either substance administered alone. Furthermore, NOR performance was lower in MDMA-pretreated mice administered MPTP compared with mice that received either substance alone.

Conclusions

These results demonstrate that MDMAMPTP negative interactions extend to the limbic and cortical regions and may result in cognitive impairment, providing further evidence that exposure to MDMA may amplify the effects of later neurotoxic insults.  相似文献   

15.
In the present study, we investigated the relation between clinical parameters and levels of interleukin (IL) -4 and -5, and tumour necrosis factor-α (TNF-α) in the leukocyte incubation medium (LIM) obtained from 26 patients with chronic periodontitis (P) and 26 control group subjects (C). The levels of cytokines IL-4 and IL -5 produced by the LIM stimulated with non-opsonised E. coli were determined using the Enzyme-Linked Immunosorbent Assay (ELISA) method and the levels of TNF-α were evaluated by applying Enzyme Amplified Sensitivity Immunoassay (EASIA). TNF-α levels in stimulated LIM were strongly positively correlated with clinical parameters such as the pocket probing depths (PPD), the clinical attachment level (CAL), the bleeding on probing (BOP) and oral hygiene index (OHI), whereas the IL-4 and IL-5 levels in the analogous medium were strongly negatively correlated with the clinical parameters. IL-4 and IL-5 levels in stimulated LIM of P group patients were significantly lower, whereas TNF-α levels were significantly higher than that in analogous medium of C group subjects. These differences were associated with the severity of periodontal disease.  相似文献   

16.
17.
Poly(d,l-lactide-co-glycolide) nanoparticle (PLGA NP) have been broadly studied as a carrier for drug delivery system of peptides and proteins. However, negative surface charge of PLGA NP using only PLGA decreases bioavailability under oral administration. In this study, novel carriers for oral delivery system through an additional bioadhesive polymer, Eudragit was introduced. Our purpose is to prepare PLGA NP using bovine serum albumin (BSA) as a model drug and Eudragit and evaluate their physiochemical characteristics, eventually expand to peptide and protein drug such as insulin or exenatide. In this study, PLGA NP were spherical and the size was around 400–500 nm. The encapsulation efficiency (EE) of PLGA NP when prepared with only PLGA was the highest, approximately 95.3 %. The polydispersity index values were low approximately 0.1, which meant their size was regular. In mucoadhesion test, we knew PLGA NP prepared by using Eudragit RS or Eudragit RL had a high affinity to mucin particles through zeta-potential change of mucin particle to cover their surface. Also, PLGA NP did not show cytotoxicity against Caco-2 cells. Especially, BSA-loaded PLGA NP using Eudragit RS 100 prepared had high EE, low polydispersity index, spherical shape having a smooth surface, sustained release profile, non-cytotoxicity and bioadhesive effect.  相似文献   

18.

Purpose

Understanding mechanisms of cellular uptake and intracellular release would enable better design of nanocarriers for delivery of nucleic acids such as siRNA and microRNA (miRNA).

Method

In this study, we investigated cellular pharmacokinetics of siRNA by co-encapsulating fluorescently labeled siRNA and molecular beacon (MB) in four different formulations of cationic lipid nanoparticles (LNPs). A miRNA mimic was also used as a probe for investigating cellular pharmacokinetics, which correlated well with RNAi activities.

Results

We tried to find the best LNP formulation based on the combination of DOTMA and DODMA. When the DOTMA/DODMA ratio was at 5/40, the LNP containing a luciferase siRNA produced the highest gene silencing activity. The superior potency of DOTMA/DODMA could be attributed to higher uptake and improved ability to facilitate siRNA release from endosomes subsequent to uptake.

Conclusions

Our findings may provide new insights into RNAi transfection pathways and have implications on cationic LNP design.  相似文献   

19.
Drug design is a process which is driven by technological breakthroughs implying advanced experimental and computational methods. Nowadays, the techniques or the drug design methods are of paramount importance for prediction of biological profile, identification of hits, generation of leads, and moreover to accelerate the optimization of leads into drug candidates. Quantitative structure–activity relationship (QSAR) has served as a valuable predictive tool in the design of pharmaceuticals and agrochemicals. From decades to recent research, QSAR methods have been applied in the development of relationship between properties of chemical substances and their biological activities to obtain a reliable statistical model for prediction of the activities of new chemical entities. Classical QSAR studies include ligands with their binding sites, inhibition constants, rate constants, and other biological end points, in addition molecular to properties such as lipophilicity, polarizability, electronic, and steric properties or with certain structural features. 3D-QSAR has emerged as a natural extension to the classical Hansch and Free–Wilson approaches, which exploit the three-dimensional properties of the ligands to predict their biological activities using robust chemometric techniques such as PLS, G/PLS, and ANN. This paper provides an overview of 1-6 dimension-based developed QSAR methods and their approaches. In particular, we present various dimensional QSAR approaches, such as comparative molecular field analysis (CoMFA), comparative molecular similarity analysis, Topomer CoMFA, self-organizing molecular field analysis, comparative molecule/pseudo receptor interaction analysis, comparative molecular active site analysis, and FLUFF-BALL, 4D-QSAR, and G-QSAR approaches.  相似文献   

20.
The role played by overexpression of tyrosine kinase epidermal growth factor receptor (EGFR), the transmembrane receptor central to numerous cellular processes comprising cell migration, adhesion, apoptosis, and cell proliferation, has been highlighted in various cancers such as prostate, breast, lung, and ovarian cancers as well as in mutations in the EGFR kinase domain. Although many therapeutic approaches have targetted EGFR, the mutations occurring in the EGFR kinase domain including L858 EGFR and T790/L858R had led to the amplification of EGFR signals, consequently leading to increased cell proliferation and cell growth. The strategies involving the inhibition of EGFR L858 and T790M have been accredited with limited achievement in addition to being associated with unwanted adverse effects as a result of crosstalk of wild-type EGFR. All current EGFR tyrosine kinase inhibitors have been identified as ATP competitive inhibitors of wild-type EGFR possessing aniline and quinazoline moiety on the ligands skeleton. Our results obtained by performing molecular docking study on Maestro 9.3 molecular docking suite indicated that CID5280343 possesses better energy conformation against wild-type EGFR as well as two mutated EGFR. Moreover, it was discovered in this study that the natural compounds CID72276, CID5280445, CID441794, and CID72277 and InterBioScreen’s library STOCK1N-78657, STOCK1N-78976, and STOCK1N-78847 have better binding conformation against gatekeeper T790M mutated EGFR concluded to be brought about by means of flexible ligands/receptor-based molecular docking protocol. Miraculous features of these compounds are their various pharmacokinetic and pharmacodynamic parameters which were found to be satisfactory as drug-like molecules. This molecular docking study also summarizes docking free energy, protein–ligands interaction profile, and pharmacokinetic and pharmacodynamic parameter of lead molecules which were tremendously helpful in enhancing the activity of these natural compounds against EGFR.  相似文献   

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