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1.
Recent studies reported that bone marrow cavity offers a widely distributed and well-vascularized microenvironment which is a considerable implantation site for bioartificial pancreas (BAP). In this study, the in vivo performance of BAPs in bone marrow was further demonstrated in a spontaneous diabetes animal. Mouse insulinoma cells encapsulating in agarose gel were enclosed in a calcium phosphate cement chamber to create a BAP. Ten BAPs were implanted into the femur bone marrow cavity of a diabetic feline. The preprandial blood glucose level, 2 h glucose curve, serum C-peptide level and physiological conditions of the recipient were recorded perioperatively. Results showed that the cat still suffered from hyperglycemia postoperatively. However, the physiological conditions of feline were improved with an increase of serum C-peptide level. The peak point of 2 h glucose curve decreased from 400 to 165-290 mg/dl. The efficiency of exogenous insulin extended from 2 to 10-14 h postoperatively which reveals that the implanted BAPs had partial function. This case report revealed that BAPs implanted in the bone marrow cavity for the spontaneous diabetic is effective. The implanted BAPs provided therapeutic benefit despite sustained hyperglycemia. Further study shall be considered to improve the outcomes of BAPs transplantation.  相似文献   

2.
Previous study found the variable miR-3202 as a potential biomarker in smoker with or without chronic obstructive pulmonary disease (COPD). This study aims to identify the molecular involvement of miR-3202 in the pathophysiology of COPD. Level of miR-3202 in blood sample of non-smoker non-COPD(C), smoker without COPD(S), smoker with stable COPD(S-COPD) and smoker with acute exacerbation COPD(AE-COPD) was observed by quantitative real-time PCR. By bioinformatics prediction, Fas apoptotic inhibitory molecule 2 (FAIM2) was identified as a potential target of miR-3202. In vitro, human bronchial epithelial (HBE) cells and cigarette smoke extract (CSE) stimulated T lymphocytes were co-cultured. Cell proliferation and apoptosis of HBE cells were determinated. In vivo, rats were exposed in cigarette smoke for 30 days and expression of miR-3202 and FAIM2 in bronchia were detected. Results showed that The miR-3202 was down-regulated in S, S-COPD and AE-COPD group when compared with C group. Decreased level of miR-3202 was also observed in CSE treated T lymphocyte. Additionally, CSE stimulation increased INF-γ and TNF-α levels and FAIM2 expression whereas inhibited Fas and FasL expressions in T lymphocytes. However, these effects were significantly suppressed by miR-3202 overexpression and enhanced by miR-3202 inhibitor. Likely to exogenous miR-3202, FAIM2 knockdown significantly inhibited HBE cells apoptosis, as well as inhibited INF-γ and TNF-α levels. In COPD rats model, miR-3202 was reduced while FAIM2 was up-regulated accordingly. Here, results suggest that high level miR-3202 in T lymphocytes may protect epithelial cells through targeting FAIM2. MiR-3202 might be used as a notable biomarker of COPD.  相似文献   

3.
Both the root and stem bark of Mahonia species were popular folk medicines. The plant has several proven biological activities including anti-bacterial, anti-fungal, and anti-inflammatory effects. However, Mahonia has not been studied for its anticancer effects. In the present study, we made extracts from Mahonia oiwakensis (MOE), a selected species in Taiwan, and investigated their effects on various human lung cells. We found that MOE-induced apoptotic death in human A549 non-small-cell lung carcinoma (NSCLC) cells in a dose- and time-dependent manner. Treatment with the extracts also caused an increase in the sub-G1 fraction of cells, chromosome condensation, and DNA fragmentation. The mitochondrial-mediated pathway was implicated in this MOE-induced apoptosis as evidenced by the activation of the caspase cascade, cleavage of poly (ADP-ribose) polymerase (PARP), disruption of mitochondrial membrane potential, and release of cytochrome C. A higher ratio of Bax/Bcl-2 proteins and cleavage of Bid were also observed in MOE-induced cell apoptosis. In A549 tumor-xenografted nude mice, MOE also retarded in vivo proliferation (P < 0.05) and induced apoptosis in tumor cells, as shown by a decrease in Ki-67-positive staining (P < 0.05) and increased transferase-mediated dUTP nick-end labeling (TUNEL)-positive staining (P < 0.05). In conclusion, MOE inhibits the growth of human lung cancer cells in vitro and in vivo, suggesting that it may have therapeutic potential against human lung cancer.  相似文献   

4.
The G protein-coupled receptor 119 (GPR119) is highly expressed in pancreatic β-cells. On activation, this receptor enhances the effect of glucose-stimulated insulin secretion (GSIS) via the elevation of intracellular cAMP concentrations. Although GPR119 agonists represent promising oral antidiabetic agents for the treatment of type 2 diabetes therapy, they suffer from the inability to adequately directly preserve β-cell function. To identify a new structural class of small-molecule GPR119 agonists with both GSIS and the potential to preserve β-cell function, we screened a library of synthetic compounds and identified a candidate molecule, AS1269574, with a 2,4,6-tri-substituted pyrimidine core. Here, we examined the preliminary in vitro and in vivo effects of AS1269574 on insulin secretion and glucose tolerance. AS1269574 had an EC50 value of 2.5 μM in HEK293 cells transiently expressing human GPR119 and enhanced insulin secretion in the mouse pancreatic β-cell line MIN-6 only under high-glucose (16.8 mM) conditions. This contrasted with the action of the sulfonylurea glibenclamide, which also induced insulin secretion under low-glucose conditions (2.8 mM). In in vivo studies, a single administration of AS1269574 to normal mice reduced blood glucose levels after oral glucose loading based on the observed insulin secretion profiles. Significantly, AS1269574 did not affect fed and fasting plasma glucose levels in normal mice. Taken together, these results suggest that AS1269574 represents a novel structural class of small molecule, orally administrable GPR119 agonists with GSIS and promising potential for the treatment of type 2 diabetes.  相似文献   

5.
A functional assessment of Bacillus thuringiensis (Bt) toxin receptors in the midgut of lepidopteran insects will facilitate understanding of the toxin mode of action and provide effective strategies to counter the development of resistance. In this study, we produced anti-aminopeptidase (APN) and anti-cadherin sera with purified Cry1Ac toxin-binding APN or cadherin fragments from Heliocoverpa armigera. Antisera were evaluated for their effects on Cry1Ac toxicity through bioassays. Our results indicated that both the anti-APN and anti-cadherin sera reduced Cry1Ac toxicity in vivo, although cadherin antiserum reduced toxicity more than APN antiserum. These results suggest that both APN and cadherin are involved in Cry1Ac intoxication of H. armigera, evidence that the pore formation model may be representative of Cry1Ac toxin mode of action in this insect.  相似文献   

6.
Photosynthesis in purple bacteria is performed by pigment–protein complexes that are closely packed within specialized intracytoplasmic membranes. Here we report on the influence of carotenoid composition on the organization of RC–LH1 pigment–protein complexes in intact membranes and cells of Rhodobacter sphaeroides. Mostly dimeric RC–LH1 complexes could be isolated from strains expressing native brown carotenoids when grown under illuminated/anaerobic conditions, or from strains expressing green carotenoids when grown under either illuminated/anaerobic or dark/semiaerobic conditions. However, mostly monomeric RC–LH1 complexes were isolated from strains expressing the native photoprotective red carotenoid spheroidenone, which is synthesized during phototrophic growth in the presence of oxygen. Despite this marked difference, linear dichroism (LD) and light-minus-dark LD spectra of oriented intact intracytoplasmic membranes indicated that RC–LH1 complexes are always assembled in ordered arrays, irrespective of variations in the relative amounts of isolated dimeric and monomeric RC–LH1 complexes. We propose that part of the photoprotective response to the presence of oxygen mediated by synthesis of spheroidenone may be a switch of the structure of the RC–LH1 complex from dimers to monomers, but that these monomers are still organized into the photosynthetic membrane in ordered arrays. When levels of the dimeric RC–LH1 complex were very high, and in the absence of LH2, LD and ?LD spectra from intact cells indicated an ordered arrangement of RC–LH1 complexes. Such a degree of ordering implies the presence of highly elongated, tubular membranes with dimensions requiring orientation along the length of the cell and in a proportion larger than previously observed.  相似文献   

7.
Lipid homeostasis in liver is known to be altered with diabetes mellitus, ultimately leading to liver damage and related complications. The present work aimed to evaluate changes in the liver phospholipid profile after 4 months of uncontrolled hyperglycemia. Twenty Wistar rats were divided into two groups: control and streptozotocin-treated (T1DM). After 4 months, animals were sacrificed and morphological characterization of liver was performed and related with serum markers of hepatic damage. Lipid extracts were obtained from liver and phospholipid (PL) classes were quantified. Lipid molecular species were determined by LC–MS and LC–MS/MS, and fatty acids by GC–MS. Concomitantly with signs of hepatic damage we found variations in the relative amount of phospholipid classes in T1DM, characterized by a decrease in PLs with choline head group, and by an increase in the relative content of other PL classes. A remodeling in PL fatty acyl chains was observed in T1DM liver, with a similar pattern to all the PL classes, and consisting in the reduction of 16:0 and an increase of 18:0 and 18:2 acyl chains. The observed changes in T1DM lipid profile may contribute to the altered membrane properties underlying hepatic damage, worsening the metabolic alterations that characterize T1DM.  相似文献   

8.
A convenient solid phase peptide synthetic (SPPS) route is reported for the preparation of antimycobacterial wollamides. The method is based on on-resin head-to-tail cyclization and is fast, efficient and amenable to automation. The in vitro antimycobacterial activities of the newly synthesized wollamides were evaluated against M. tuberculosis H37Rv (Mtb H37Rv). To assess their drug-likeness, in vitro pharmacokinetic (ADME) profiling was also performed. For wollamides with potent extracellular potency, intracellular activities and in vivo efficacy were determined. The results disclose the potent antimycobacterial (MICMtb H37Rv?=?1.1?µM) and suitable drug-like properties of wollamide A (4b). Out of the synthesized wollamides, four compounds (4be) exhibited potent intracellular activities against Mtb H37Rv infected human macrophages (IC50?=?0.2–1.3?µM). Results of in vivo blood exposure and efficacy assays for 4d and 4e are discussed.  相似文献   

9.
It has been demonstrated that prolonged graft survival can be achieved through inhibiting the activation of T cells, and addition of soluble CTLA4Ig and OX40Ig proteins to mixed lymphocyte reactions can effectively inhibit T cell proliferation. To explore the potential of this type of treatment in xenotransplantation, we infected streptozotocin-induced diabetic BalB/c mice (H-2d) (200 mg/kg, IV) with 5×108 pfu AdCTLA4Ig-IRES-OX40Ig on day 1 before islets transplantation through the tail vein. The results showed that this treatment prolonged the islet xenografts survival significantly. The reaction to exogenous glucose stimulation was normal and the cytokine secretion of the type Th1 cells was inhibited. The AdCTLA4Ig-IRES-OX40Ig-mediated treatment effectively induced the T cells into anergy and the Th1/Th2 cells into deviation. These results strongly supported the therapeutic potential of blockade of costimulation by Ad-CTLA4Ig-IRES-OX40Ig genes transfer in inducing the organ transplantation tolerance.  相似文献   

10.
Type 1 diabetes mellitus is an autoimmune disease caused by T cell-mediated destruction of pancreatic beta islets. With its incidence continuous rising in the pediatric age group in recent years, it is becoming a serious threat to the human health. Up to now, there has been no effective therapy for diabetes mellitus, and islet transplantation still remains a promising ap-proach to the treatment of Type 1 diabetes. However, two serious problems hinder the successful islets transplantation, tha…  相似文献   

11.
Type 1 diabetes (T1D) is caused by a T cell-mediated autoimmune response that leads to the loss of insulin-producing β cells. The optimal preclinical testing of promising therapies would be aided by a humanized immune-mediated T1D model. We develop this model in NOD-scid IL2rγnull mice. The selective destruction of pancreatic islet β cells was mediated by human T lymphocytes after an initial trigger was supplied by the injection of irradiated spleen mononuclear cells (SMC) from diabetic nonobese diabetic (NOD) mice. This resulted in severe insulitis, a marked loss of total β-cell mass, and other related phenotypes of T1D. The migration of human T cells to pancreatic islets was controlled by the β cell-produced highly conserved chemokine stromal cell-derived factor 1 (SDF-1) and its receptor C-X-C chemokine receptor (CXCR) 4, as demonstrated by in vivo blocking experiments using antibody to CXCR4. The specificity of humanized T cell-mediated immune responses against islet β cells was generated by the local inflammatory microenvironment in pancreatic islets including human CD4+ T cell infiltration and clonal expansion, and the mouse islet β-cell-derived CD1d-mediated human iNKT activation. The selective destruction of mouse islet β cells by a human T cell-mediated immune response in this humanized T1D model can mimic those observed in T1D patients. This model can provide a valuable tool for translational research into T1D.  相似文献   

12.
Severance of nervi corporis allati I (NCA I) in day-1 adult female Locusta migratoria resulted in a significant decrease and a loss of the characteristic pattern of juvenile hormone biosynthesis by the corpora allata as determined by radiochemical assay. This decrease in the rate of juvenile hormone biosynthesis was not reflected in basal oöcyte growth. The lengths of the oöcytes were the same in NCA-transectioned and in the sham-operated females. The effect of severance of both NCA I and NCA II on juvenile hormone biosynthesis and ovarian maturation was similar to the effect of NCA I severance only.Rate of juvenile hormone biosynthesis by corpora allata of fourth-instar larvae exhibited a maximum of activity in the middle of the stadium. The severance of NCA I early in the stadium resulted in a very low rate of juvenile hormone biosynthesis and a disappearance of this peak. In NCA I-transectioned larvae, the duration of the stadium was significantly increased although larvae moulted into normal fifth instar.  相似文献   

13.
The global proteome of sperm and seminal plasma of fertile stallions was investigated to determine whether associations with relative in vivo fertility exist. Seven stallions at stud in a commercial breeding station were collected throughout the breeding season and bred to a total of 164 mares to determine conception rates. On three occasions during the breeding season, raw semen was obtained from a regular collection for proteomic analysis using two-dimensional electrophoresis and also assessed for routine semen quality end points. First cycle conception rate was negatively related to ejaculate volume (r = −0.43, P = 0.05) and total IGF1 content (ng) per ejaculate (r = −0.58, P = 0.006), whereas overall pregnancy rate was positively related to sperm concentration (r = 0.56, P = 0.01). The abundance of three proteins known to be involved in carbohydrate metabolism in sperm was positively related to fertility. Furthermore, the abundance of four seminal plasma proteins were identified as being negatively related to fertility; these were identified as kallikrein-1E2 (KLK2), clusterin, and seminal plasma proteins 1 (SP1) and 2 (SP2). Abundance of cysteine-rich secretory protein 3 (CRISP3) was positively related to first cycle conception rate (r = 0.495, P = 0.027) and may provide a good marker of fertility. Based on stepwise regression analysis, clusterin and SP1 in seminal plasma together with sperm citrate synthase were predictive of fertility (r = 0.77, P < 0.0001). This study identified proteins within sperm and seminal plasma that could serve as biomarkers of semen quality and fertility in stallions.  相似文献   

14.
In an in vitro experiment, aluminosilicates (Atox® and Novasil™ Plus) and a yeast cell wall derivate (Mycosorb®) were used as sequestering agents (SAs) to verify their capacity for binding aflatoxin B1 (AFB1) in vitro. SAs were individually mixed at three different ratios with AFB1 (1:5000, 1:50,000 and 1:500,000, w/w) in water (CTR), rumen fluid from a lactating cow with a low rumen pH (LRS) or rumen fluid from a dry cow with a high rumen pH (HRS), and then used in a 3 × 3 × 3 factorial arrangement of a completely randomized design. At the 1:500,000 AF:SA ratio Atox® and Novasil™ Plus sequestered over 0.87 and 0.98 of the AFB1 in the CTR and rumen solutions (LRS and HRS), respectively. This efficacy decreased when the amount of clays was reduced, with higher values (P<0.001) for Atox® compared with Novasil™ Plus (0.50 vs. 0.28 in CTR; 0.58 vs. 0.16 in LRS and 0.44 vs. 0.27 in HRS). Mycosorb® had a lower sequestering efficacy (P<0.001) in all of tested experimental conditions, with 0.34 being the maximum value obtained in the CTR solution.  相似文献   

15.
16.
The role of complement in the control of the primary Schistosoma mansoni infection in mice was investigated in vivo. The number of recovered adult schistosomes 6–7 weeks postinfection was used as a parasitological criterion of immunity. No significant difference in the worm burden was observed between C5-sufficient and C5-deficient mice. In contrast, when cobra venom factor (CVF) was injected into normal or C5-deficient mice 24 hr before challenge, a significant increase of the worm burden was noticed in comparison to the untreated mice. These results indicated that, although C5 and probably the late complement components are not essential for the control of the primary infection, the alternative pathway and some of its components are involved. In fact, the injection of C3 2 hr before infection of CVF-treated mice completely restored the immunity. A role for C3, in association with effector cells, in the nonspecific immunity occurring in the first hours after a primary S. mansoni infection is suggested.  相似文献   

17.
Convolutriloba retrogemma, like other members of the genus and other symbiotic acoels, does not lend itself well to established methods for the detection and quantification of photosynthate translocation from symbiont to host. We describe a novel method for indirectly detecting evidence of photosynthate movement, in vivo, utilizing differential weight change in animals subjected to light and dark treatments without holozoic feeding. Unfed acoels kept in light lost 28% of their original weight while those kept in the dark lost 41%. Also described is a refined method for the separation of algal symbionts from host tissue in these species, as well as a method for determining accurate wet-weight of this and other soft-bodied, invertebrate species.  相似文献   

18.
Lysophosphatidic acid (LPA) is a pro-fibrotic mediator acting via specific receptors (LPARs) and is synthesized by autotaxin, that increases with obesity. We tested whether LPA could play a role in adipose tissue (AT)-fibrosis associated with obesity. Fibrosis [type I, III, and IV collagens (COL), fibronectin (FN), TGFβ, CTGF and αSMA] and inflammation (MCP1 and F4/80) markers were quantified: (i) in vivo in inguinal (IAT) and perigonadic (PGAT) AT from obese-diabetic db/db mice treated with the LPAR antagonist Ki16425 (5 mg/kg/day ip for 7 weeks); and (ii) in vitro in human AT explants in primary culture for 72 h in the presence of oleoyl-LPA (10 μM) and/or Ki16425 (10 μM) and/or the HIF-1α inhibitor YC-1 (100 μM). Treatment of db/db mice with Ki16425 reduced Col I and IV mRNAs in IAT and PGAT while Col III mRNAs were only reduced in IAT. This was associated with reduction of COL protein staining in both IAT and PGAT. AT explants showed a spontaneous and time-dependent increase in ATX expression and production of LPA in the culture medium, along with increased levels of Col I and III, TGFβ and αSMA mRNAs and of COL protein staining. In vitro fibrosis was blocked by Ki16425 and was further amplified by oleoyl-LPA. LPA-dependent in vitro fibrosis was blocked by co-treatment with YC1. Our results show that endogenous and exogenous LPA exert a pro-fibrotic activity in AT in vivo and in vitro. This activity could be mediated by an LPA1R-dependent pathway and could involve HIF-1α.  相似文献   

19.

Background

Endoglin (CD105) is overexpressed on tumor cells and tumor vasculatures, making it a potential target for diagnostic imaging and therapy of different neoplasms. Therefore, studies on nanocarrier systems designed for endoglin-directed diagnostic and drug delivery purposes would expose the feasibility of targeting endoglin with therapeutics.

Methods

Liposomes carrying high concentrations of a near-infrared fluorescent dye in the aqueous interior were prepared by the lipid film hydration and extrusion procedure, then conjugated to single chain antibody fragments either selective for murine endoglin (termed mEnd-IL) or directed towards human endoglin (termed hEnd-IL). A combination of Dynamic Light Scattering, electron microscopy, cell binding and uptake assays, confocal microscopy and in vivo fluorescence imaging of mice bearing xenografted human breast cancer and human fibrosarcoma models were implemented to elucidate the potentials of the liposomes.

Results

The mEnd-IL and hEnd-IL were highly selective for the respective murine- and human endoglin expressing cells in vitro and in vivo. Hence, the hEnd-IL bound distinctly to the tumor cells and enabled suitable fluorescence imaging of the tumors, whereas the mEnd-IL bound the tumor vasculature, but also to the liver, kidney and lung vasculature of mice.

Conclusions

The work highlights key differences between targeting vascular (murine) and neoplastic (human) endoglin in animal studies, and suggests that the hEnd-IL can serve as a delivery system that targets human endoglin overexpressed in pathological conditions.

General significance

The endoglin-targeting liposomes presented herewith represent strategic tools for the future implementation of endoglin-directed neoplastic and anti-angiogenic therapies.  相似文献   

20.
Infection of mucosal epithelial cells by Shigella species leads to an intense and acute inflammatory bowel disease that is characterized by watery diarrhea and purulent discharge. Mucin production is a common defense mechanism to protect the underlying mucosa against pathogens. The molecular mechanism(s) underlying mucin induction is unknown in Shigellosis. In this study, we have evaluated the relationship between Shigella infection, the expression of MUC2 and MUC5AC and the participation of signaling molecules TNF-α, PKC and ERK1/2. Shigella infection up-regulated MUC2 and MUC5AC expression in 6–8 h, through activation of TNF-α, PKC and ERK1/2. These results confirm that, in response to Shigella infection, the normal expression pattern of MUC-2 and MUC-5AC is altered. This in vivo study brings new insights into the molecular pathogenesis of Shigellosis and new potential therapeutic targets for Shigellosis.  相似文献   

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