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1.
Three Lactobacillus strains (LOCK 0900, LOCK 0908, LOCK 0919) out of twenty-four isolates were selected according to their antagonistic activity against pathogenic bacteria, resistance to low pH and milieu of bile salts. Intragastric administration of a mixture of these strains to Balb/c mice affected cytokine TH1-TH2 balance toward nonallergic TH1 response. Spleen cells, isolated from lactobacilli-treated mice and re-stimulated in vitro with the mixture of heat-inactivated tested strains, produced significantly higher amounts of anti-allergic tumor necrosis factor- and interferon-γ than control animals whereas the level of pro-allergic interleukin-5 was significantly lower. Lactobacillus cells did not translocate through the intestinal barrier into blood, liver and spleen; a few Lactobacillus cells found in mesenteric lymph nodes could create antigenic reservoir activating the immune system. The mixture of Lactobacillus LOCK 0900, LOCK 0908 and LOCK 0919 strains represents a probiotic bacterial preparation with possible use in prophylaxis and/or therapy of allergic diseases.  相似文献   

2.
Six pea (Pisum sativum L.) cultivars (Adept, Komet, Lantra, Olivin, Oskar, Tyrkys) were transformed via Agrobacterium tumefaciens strain EHA105 with pBIN19 plasmid carrying reporter uidA (β-glucuronidase, GUS, containing potato ST-LS1 intron) gene under the CaMV 35S promoter, and selectable marker gene nptII (neomycin phosphotransferase II) under the nos promoter. Two regeneration systems were used: continual shoot proliferation from axillary buds of cotyledonary node in vitro, and in vivo plant regeneration from imbibed germinating seed with removed testa and one cotyledon. The penetration of Agrobacterium into explants during co-cultivation was supported by sonication or vacuum infiltration treatment. The selection of putative transformants in both regeneration systems carried out on media with 100 mg dm−3 kanamycin. The presence of introduced genes was verified histochemically (GUS assay) and by means of PCR and Southern blot analysis in T0 putative transformants and their seed progenies (T1 to T3 generations). Both methods, but largely in vivo approach showed to be genotype independent, resulting in efficient and reliable transformation system for pea. The in vivo approach has in addition also benefit of time and money saving, since transgenic plants are obtained in much shorter time. All tested T0 – T3 plants were morphologically normal and fertile.This research was supported by the National Agency for Agricultural Research (grants No. QE 0046 and QF 3072) and Ministry of Education of the Czech Republic (grant No. ME 433).  相似文献   

3.
Polysomes synthesizing both α1 and α2 collagen chains have been identified by means of an in vitro system for completion and release of nascent polypeptides. Their size indicates that the mRNA for α chains is monocistronic.  相似文献   

4.

Introduction  

SPARC is a matricellular protein, which, along with other extracellular matrix components including collagens, is commonly over-expressed in fibrotic diseases. The purpose of this study was to examine whether inhibition of SPARC can regulate collagen expression in vitro and in vivo, and subsequently attenuate fibrotic stimulation by bleomycin in mouse skin and lungs.  相似文献   

5.
Mature osteoclasts, multinucleated giant cells responsible for bone resorption, are terminally differentiated cells with a short life span. Recently, we have demonstrated that osteoclast apoptosis is regulated by ERK activity and Bcl-2 family member Bim. In this paper, we summarize the methods we used to study osteoclast apoptosis in vitro and in vivo. Using adenovirus and retrovirus vectors, we were able to introduce foreign genes into osteoclasts and examine their effects on osteoclast survival in vitro. In addition, we established the modified methods for in situ hybridization and BrdU labeling of bone sections from mice to study osteoclast survival in vivo. The detailed methods described here could be useful for studying the biological process in bone.  相似文献   

6.
Valsartan orodispersible tablets have been developed at 40-mg dose, with the intention of facilitating administration to patients experiencing problems with swallowing and hopefully, improving its poor oral bioavailability. Work started with selecting drug compatible excipients depending on differential scanning calorimetric analysis. A 33 full factorial design was adopted for the optimization of the tablets prepared by freeze-drying technique. The effects of the filler type, the binder type, and the binder concentration were studied. The different tablet formulas were characterized for their physical properties, weight variation, disintegration time, surface properties, wetting properties, and in vitro dissolution. Amongst the prepared 27 tablet formulas, formula number 6 (consisting of 4:6 valsartan:mannitol and 2% pectin) was selected to be tested in vivo. Oral bioavailability of two 40 mg valsartan orodispersible tablets was compared to the conventional commercial tablets after administration of a single dose to four healthy volunteers. Valsartan was monitored in plasma by high-performance liquid chromatography. The apparent rate of absorption of valsartan from the prepared tablets (C max = 2.879 μg/ml, t max = 1.08 h) was significantly higher than that of the conventional tablets (C max = 1.471 μg/ml, t max = 2.17 h), P ≤ 0.05. The relative bioavailability calculated as the ratio of mean total area under the plasma concentration–time curve for the orodispersible tablets relative to the conventional ones was 135%. The results of the in vivo study revealed that valsartan orodispersible tablets would be advantageous with regards to improved patient compliance, rapid onset of action, and increase in bioavailability.  相似文献   

7.

Background  

There is a substantial discrepancy between in vitro and in vivo experiments. The purpose of the present work was development of a theoretical framework to enable improved prediction of in vivo response from in vitro bioassay results.  相似文献   

8.
HIV protease inhibitors are an integral part of effective anti-HIV therapy. The drugs block HIV protease, prevent proper packaging of HIV virions, and decrease the HIV viral burden in the peripheral blood of infected individuals. In addition to direct anti-viral effects, the HIV protease inhibitors also modulate apoptosis. A growing body of work demonstrates the anti-apoptotic effects of HIV protease inhibitors on CD4+ and CD8+ T cells during HIV infection. The mechanism of this apoptosis inhibition is supported by several proposed hypotheses for how they alter the fate of the cell, including preventing adenine nucleotide translocator pore function, which consequently prevents loss of mitochondrial transmembrane potential. More recently, the anti-apoptotic effects of the HIV protease inhibitors have been tested in non-HIV, non-immune cell, whereby protease inhibitors prevent apoptosis, and disease in animal models of sepsis, hepatitis, pancreatitis and stroke. Interestingly, when HIV protease inhibitors are used at supra-therapeutic concentrations, they exert pro-apoptotic effects. This has been demonstrated in a number of tumor models. Although it is unclear how HIV protease inhibitors can induce apoptosis at increased concentrations, future research will define the targets of the immunomodulation and reveal the full clinical potential of this intriguing class of drugs.  相似文献   

9.
10.
The aim of this investigation was to improve in vitro the technique of production of double haploid in Indica hybrid rice by combining anther culture, hormone shock and doubling chromosome. It was discussed how to avoid somaclonal variation during culturing and to reduce the time of this process. The anthers of KDML 105 × SPR 1 (Indica × Indica) were cultured in Linsmaier and Skoog (LS) medium, which contained nutrients, growth regulators [(2,4,-dichlorophenoxy acetic acid (2,4-D) and naphthalene acetic acid (NAA)] and organic compounds, and then subcultured by inducing embryo-like structure (ELS) LS media. During 4 weeks used LS media supplemented with 10 μM KNO3 + 2 mg/L 2,4-D + 2 mg/L NAA + 20% coconut water + 1 mg/L of activated charcoal had induced high embryogenic frequent callus with length of 4–5 mm. The supplementation of 0.2 g/L colchicine and 100 μM 2,4-D was the most efficient in LS media. Over 70% of viable double haploid ELS were produced in 8 weeks and subcultured only twice compared with conventional anther which takes more than 12 weeks. This new technique can therefore be applied to rice in order in shorten time to produce higher number of double haploid plantlets.  相似文献   

11.
We investigated the activity of caspofungin against a Candida tropicalis clinical isolate showing paradoxical growth in vitro. BALB/c mice immunosuppressed by cyclophosphamide were infected intraperitoneally using 107 CFU/mouse. Caspofungin was administered intraperitoneally once daily for 5 days or as a single dose using the following doses: 0.12, 0.25, 1, 2, 3, 5, and 15 mg/kg. The single dose of caspofungin was effective only at 5 and 15 mg/kg concentrations (100% survival). Five-day caspofungin treatment led to 100% survival at doses of 1 mg/kg or higher. Caspofungin treatment significantly decreased the number of viable yeasts in the peritoneal lavage samples as well as in the infected abscesses at doses 1, 3, 5, and 15 mg/kg caspofungin as compared to the untreated control (P<0.001 in all cases), and even to the group treated with 0.12 mg/kg caspofungin (P<0.05 in all cases). At 2 mg/kg caspofungin dose, sterilization of the internal organs was reproducibly incomplete, suggesting that the role of paradoxical growth in the late clinical failure cannot be excluded.  相似文献   

12.

Background  

Evolution of toxicity testing is predicated upon using in vitro cell based systems to rapidly screen and predict how a chemical might cause toxicity to an organ in vivo. However, the degree to which we can extend in vitro results to in vivo activity and possible mechanisms of action remains to be fully addressed.  相似文献   

13.
SV40 virus DNA transcribes differently in vitro from in vivo. In a series of parallel experiments, the in vitro and in vivo single-stranded DNAs are shown to differ in structure.  相似文献   

14.
Polyamines are ubiquitous polycationic compounds that mediate fundamental aspects of cell growth, differentiation, and cell death in eukaryotic and prokaryotic organisms. In plants, polyamines are implicated in a variety of growth and developmental processes, in addition to abiotic and biotic stress responses. In the last decade, mutant studies conducted predominantly in Arabidopsis thaliana revealed an obligatory requirement for polyamines in zygotic and somatic embryogenesis. Moreover, our appreciation for the intricate spatial and temporal regulation of intracellular polyamine levels has advanced considerably. The exact molecular mechanism(s) through which polyamines exert their physiological response remains somewhat enigmatic and likely serves as a major area for future research efforts. In the following review, we discuss recent advances in the plant polyamine field, which range from metabolism and mutant characterization to molecular genetics and potential mode(s) of polyamine action during growth and development in vitro and in vivo. This review will also focus on the specific role of polyamines during embryogenesis and organogenesis.  相似文献   

15.

Background  

Hyaluronic acid (HA) is present in many tissues; its presence in serum may be related to certain inflammatory conditions, tissue damage, sepsis, liver malfunction and some malignancies. In the present work, our goal was to investigate the significance of hyaluronic acid effect on erythrocyte flow properties. Therefore we performed in vitro experiments incubating red blood cells (RBCs) with several HA concentrations. Afterwards, in order to corroborate the pathophysiological significance of the results obtained, we replicated the in vitro experiment with ex vivo RBCs from diagnosed rheumatoid arthritis (RA) patients, a serum HA-increasing pathology.  相似文献   

16.
Summary Shoot apex, nodal, and leaf explants of Stevia rebaudiana Bertoni can regenerate shoots when cultured on Murashige and Skoog (MS) medium supplemented with 6-benzyladenine (BA; 8.87 μM) and indole-3-acetic acid (5.71 μM). Rooting of the in vitro-derived shoots could be achieved following subculture onto auxin-containing medium. A survival rate of 70% was recorded at the hardening phase on the substrate cocopeat. The presence of the sweet diterpene glycosides, viz. stevioside and rebaudioside, was confirmed in the in vitro-derived tissues of Stevia using HPTLC techniques. Callus cultured on agar-solidified MS medium supplemented with BA (8.87 μM) and indole-3-butyric acid (9.80 μM) showed the highest sweetener content.  相似文献   

17.
The aim of the present study was to examine the antioxidant activity of three Veronica species (Plantaginaceae). The antioxidant potential of various extracts obtained from aerial flowering parts was evaluated by DPPH-free (1,1-diphenyl-2-picrylhydrazyl-free) radical scavenging activity and ferric-reducing antioxidant power assays. Considerable antioxidant activity was observed in the plant samples (FRAP values ranged from 0.97 to 4.85 mmol Fe2+/g, and DPPH IC50 values from 12.58 to 66.34 μg/ml); however, these levels were lower than the activity of the control compound butylated hydroxytoluene (BHT) (FRAP: 10.58 mmol Fe2+/g; DPPH IC50: 9.57 μg/ml). Also, the in vivo antioxidant effects were evaluated in several hepatic antioxidant systems in rats (activities of glutathione peroxidase, glutathione reductase, peroxidase, catalase, xanthine oxidase, glutathione content and level of thiobarbituric acid reactive substances) after treatment with different Veronica extracts, or in combination with carbon tetrachloride (CCl4). Pretreatment with 100 mg/kg b.w. of Veronica extracts inhibited CCl4-induced liver injury by decreasing TBA-RS level, increasing GSH content, and bringing the activities of CAT and Px to control levels. The present study suggests that the extracts analyzed could protect the liver cells from CCl4-induced liver damage by their antioxidative effect on hepatocytes.  相似文献   

18.
The localization was determined of the triterpenoids, asiaticoside and madecassoside, in different organs of glasshouse-grown plants and cultured material, including transformed roots, of two phenotypes of Centella asiatica (L.) Urban of Malaysian origin. Methanolic extracts of asiaticoside and madecassoside were prepared for gradient HPLC analysis. The two phenotypes of C. asiatica exhibited differences in terpenoid content that were tissue specific and varied between glasshouse-grown plants and tissue culture-derived material. Terpenoid content was highest in leaves, with asiaticoside (0.79 ± 0.03 and 1.15 ± 0.10 % of dry mass) and madecassoside [0.97 ± 0.06 and 1.65 ± 0.01 %(d.m.)] in the fringed (F) and smooth leaf (S) phenotypes, respectively. Roots of the F-phenotype contained the lowest content of asiaticoside [0.12 ± 0.01 %(d.m.)], whereas petioles of S-phenotype plants contained the lowest content of asiaticoside [0.16 ± 0.01 %(d.m.)] and madecassoside [0.18 ± 0.14 %(d.m.)]. Transformed roots were induced using Agrobacterium rhizogens and their growth was maximal on Murashige and Skoog basal medium supplemented with 60 g dm−3 sucrose. However, asiaticoside and madecassoside were undetectable in transformed roots and undifferentiated callus.  相似文献   

19.
An effective in vitro protocol for rapid clonal propagation of Echinacea purpurea (L.) Moench through tissue culture was described. The in vitro propagation procedure consisted of four stages: 1) an initial stage - obtaining seedlings on Murashige and Skoog (MS) basal medium with 0.1 mg L−1 6-benzylaminopurine, 0.1 mg L−1 α-naphthalene acetic acid and 0.2 mg L−1 gibberellic acid; 2) a propagation stage — shoot formation on MS medium supplemented with 1 mg L−1 6-benzylaminopurine alone resulted in 9.8 shoots per explant and in combination with 0.1 mg L−1 α-naphthalene acetic acid resulted in 16.2 shoots per explant; 3) rooting stage — shoot rooting on half strength MS medium with 0.1 mg L−1 indole-3-butyric acid resulted in 90% rooted microplants; 4) ex vitro acclimatization of plants. The mix of peat and perlite was the most suitable planting substrate for hardening and ensured high survival frequency of propagated plants. Significant higher levels were observed regarding water-soluble and lipid-soluble antioxidant capacities (expressed as equivalents of ascorbate and α-tocopherol) and total pnenols content in extracts of Echinaceae flowers derived from in vitro propagated plants and adapted to field conditions in comparison with traditionally cultivated plants.  相似文献   

20.
Vascular smooth muscle cell (VSMC) proliferation and migration are pivotal for the pathogenesis of atherosclerosis and post-angioplasty restenosis. We have recently reported that a disintegrin and metalloproteinase with thrombospondin motifs-7 (ADAMTS-7), a novel metalloproteinase, contributes directly to neointima formation by mediating VSMC migration. However, whether ADAMTS-7 affects VSMC proliferation remains unclear. In this study, we found that luminal adenoviral delivery of ADAMTS-7 aggravated intimal hyperplasia 7 d after injury, paralleled by an increased percentage of PCNA-positive cells in both intima and media. In contrast, perivascular administration of ADAMTS-7 siRNA, but not scrambled siRNA to injured arteries attenuated intimal thickening at day 7, paralleled with reduced intimal VSMC replication, without alteration of VSMC proliferation in the media. In accordance, [3H]-thymidine incorporation assay in primary cultured rat VSMCs revealed an enhanced replication rate (by 61%) upon ADAMTS-7 overexpression and retarded proliferation (by 23%) upon ADAMTS-7 siRNA administration. Our data demonstrates that ADAMTS-7 promotes VSMC proliferation both in vitro and in vivo. ADAMTS-7 may therefore serve as a novel therapeutic target for atherosclerosis and post-angioplasty restenosis.  相似文献   

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