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41.
42.
Dr. Predrag Sikirić PhD Sven Seiwerth PhD Željko Grabarević PhD Rudolf Ručman PhD Marijan Petek PhD Vjekoslav Jagić PhD Branko Turković PhD Ivo Rotkvić PhD Stjepan Miše PhD Ivan Zoričić MD Miroslav Gjurašin MD Paško Konjevoda MD Jadranka Šeparović PhD Danica Ljubanović MD Branka Artuković MD Mirna Bratulić MD Marina Tišljar MD Ljubica Jurina MD Gojko Buljat PhD Pavao Miklić PhD Anton Marović PhD 《Digestive diseases and sciences》1996,41(8):1604-1614
Very recently, the integrity of capsaicin somatosensory neurons and their protection were suggested to be related to the activity in nociception of a newly discovered 15-amino acid peptide, BPC 157, shown to have strong beneficial effect on intestinal and liver lesions. Therefore, from this viewpoint, we have studied the gastroprotective effect of the pentadecapeptide BPC 157, on gastric lesions produced in rats by 96% ethanol, restraint stress, and indomethacin. The possible involvement of sensory neurons in the salutary actions of BPC 157 (10µg/kg, 10 ng/kg intraperitoneally) was studied with capsaicin, which has differential effects on sensory neurons: a high dose in adult (125 mg/kg subcutaneously, 3 months old) or administration (50 mg/kg subcutaneously) to neonatal animals (age of the 7 days) destroys sensory fibers, whereas a low dose (500µg/kg intraperitoneally) activates neurotransmitter release and protective effects on the mucosa. In the absence of capsaicin, BPC 157 protected gastric mucosa against ethanol, restraint, and indomethacin application. In the presence of neurotoxic doses of capsaicin, the negative influence of capsaicin on restraint, ethanol, or indomethacin lesions consistently affected salutary activity of BPC 157. However, BPC 157 protection was still evident in the capsaicin-treated rats (either treated as adults or as newborns) in all of these assays. Interestingly, after neonatal capsaicin treatment, a complete abolition of BPC gastroprotection was noted if BPC 157 was applied as a single nanogram-regimen, but the mucosal protection was fully reversed when the same dose was used daily. In line with the excitatory dose of capsaicin the beneficial effectiveness of BPC 157 appears to be increased as well. Taken together, these data provide evidence for complex synergistic interaction between the beneficial effectiveness of BPC 157 and peptidergic sensory afferent neuron activity. 相似文献
43.
Munclinger MJ Thornton AS Schutte DP Sliwa K 《International journal of cardiology》2004,93(2-3):335-337
Aortocaval fistula (ACF) represents a rare complication of abdominal aortic aneurysm (AAA) that may lead to hyperdynamic heart failure. We briefly describe a 58-year-old man with an old myocardial infarction, who developed leg oedema and worsening exertional dyspnea due to ACF complicating an AAA. This uncommon case highlights that an appropriate investigation for AAA and ACF should be performed in high-risk patients presenting with a history of worsening leg oedema and dyspnea in the absence of an obvious precipitating factor. 相似文献
44.
45.
Vermeulen K Strnad M Havlícek L Van Onckelen H Lenjou M Nijs G Van Bockstaele DR Berneman ZN 《Experimental hematology》2002,30(10):1107-1114
OBJECTIVE: Regulation of the cell cycle by cyclin-dependent kinase (CDK) activity occurs at multiple levels and is often altered in human cancers. Therefore, CDK activity has been targeted for drug discovery, and a number of small molecules have now been identified as CDK inhibitors. Plant cytokinin analogues with CDK inhibitory activity and antiproliferative effects were studied to characterize the cellular basis of the cytotoxic effect. METHODS: The IC(50) value (concentration at which 50% of the cell proliferation is inhibited) and AC(50) value (concentration at which 50% of the cell population is apoptotic) were determined by flow cytometry and microscopy, respectively. A new multiparametric flow cytometric analysis was used to study the sequence of different apoptotic events. In this assay, analysis of phosphatidylserine exposure, mitochondrial membrane depolarization, activation of caspases and DNA condensation were combined. RESULTS: Treatment of Jurkat and KG1 cells with the CDK inhibitors results in a decrease of viable cells and a parallel increase in percentage of apoptotic cells. Apoptosis was accompanied by a rapid decrease of mitochondrial membrane potential, which precedes DNA condensation, exposure of phosphatidylserine and activation of caspases. CONCLUSIONS: The main cellular mechanism of the antiproliferative effect of plant cytokinin analogues with CDK inhibitory activity is the induction of apoptosis. The multiparametric flow cytometric technique allowed to follow the kinetics of various aspects of apoptotic cell changes and demonstrated that cytokinin analogue-induced apoptosis starts through the mitochondrial pathway. This technique could also become of value for the rapid screening of pro-apoptotic properties of chemotherapeutic compounds. 相似文献
46.
The prohormone convertase PC2 requires the aid of a helper protein, known as 7B2, for production of active enzyme. Deletion of 7B2 results in a lethal phenotype resembling Cushing's disease. In this study, we have investigated the effect of a single low dose of recombinant adenovirus vector encoding 7B2 and delivered directly to the pituitary of 7B2 nulls on pituitary ACTH, plasma ACTH, corticosterone, alpha MSH and glucose, and survival time. We show that after injection of recombinant adenovirus encoding 27-kDa 7B2 into 7B2 nulls, transgene expression, as measured by RIA for 7B2, exhibits a transient elevation in the pituitary and blood, with a slight but significant elevation of PC2 activity in pituitaries of 7B2 nulls and a drop in the level of circulating ACTH concomitant with a small increase in circulating alpha MSH. The level of circulating blood glucose was increased, and that of corticosterone was decreased. Lastly, slight but significantly prolonged survival times were observed. These data showing partial rescue of 7B2 nulls support the idea that adenoviral administration of 7B2 will represent an effective means to study the role of this interesting neuroendocrine protein on endocrine function in vivo. 相似文献
47.
48.
Lidija Izrael-
ivkovi Milena Rikalovi Gordana Gojgi-Cvijovi Saa Kazazi Miroslav Vrvi Ilija Br
eski Vladimir Bekoski Branka Lon
arevi Kristina Gop
evi Ivanka Karadi 《RSC advances》2018,8(19):10549
Pseudomonas aeruginosa san ai is a promising candidate for bioremediation of cadmium pollution, as it resists a high concentration of up to 7.2 mM of cadmium. Leaving biomass of P. aeruginosa san ai exposed to cadmium has a large biosorption potential, implying its capacity to extract heavy metal from contaminated medium. In the present study, we investigated tolerance and accumulation of cadmium on protein level by shotgun proteomics approach based on liquid chromatography and tandem mass spectrometry coupled with bioinformatics to identify proteins. Size exclusion chromatography was used for protein prefractionation to preserve native forms of metalloproteins and protein complexes. Using this approach a total of 60 proteins were observed as up-regulated in cadmium-amended culture. Almost a third of the total numbers of up-regulated were metalloproteins. Particularly interesting are denitrification proteins which are over expressed but not active, suggesting their protective role in conditions of heavy metal exposure. P. aeruginosa san ai developed a complex mechanism to adapt to cadmium, based on: extracellular biosorption, bioaccumulation, the formation of biofilm, controlled siderophore production, enhanced respiration and modified protein profile. An increased abundance of proteins involved in: cell energy metabolism, including denitrification proteins; amino acid metabolism; cell motility and posttranslational modifications, primarily based on thiol-disulfide exchange, were observed. Enhanced oxygen consumption of biomass in cadmium-amended culture versus control was found. Our results signify that P. aeruginosa san ai is naturally well equipped to overcome and survive high doses of cadmium and, as such, has a great potential for application in bioremediation of cadmium polluted sites.When exposed to cadmium a highly resistant strain P. aeruginosa san ai responds by an increased metalloprotein expression (particularly denitrification proteins), an enhanced respiration, and a pronounced thiol-disulfide protein modifications. 相似文献
49.
Lukasova Vera Buzgo Matej Vocetkova Karolina Kubíkov Tereza Tonar Zbynk Doupnik Miroslav Blahnova Veronika Litvinec Andrej Sovkova Vera Voltrov Barbora Staffa Andrea Svora Petr Kralickova Milena Amler Evzen Filova Eva Rustichelli Franco Rampichova Michala 《RSC advances》2018,8(39):21889
Bone regeneration is a long-term process requiring proper scaffolding and drug delivery systems. The current study delivers a three-dimensional (3D) scaffold prepared by blend centrifugal spinning loaded with the osteogenic supplements (OS) β-glycerol phosphate, ascorbate-2-phosphate and dexamethasone. The OS were successfully encapsulated into a fibrous scaffold and showed sustained release for 30 days. Furthermore, biological testing showed the osteoinductive properties of the scaffolds on a model of human mesenchymal stem cells and stimulatory effect on a model of osteoblasts. The osteoinductive properties were further proved in vivo in critical size defects of rabbits. The amount of bone trabecules was bigger compared to control fibers without OS. The results indicate that due to its long-term drug releasing properties, single step fabrication process and 3D structure, the system shows ideal properties for use as a cell-free bone implant in tissue-engineering.Bone regeneration is a long-term process requiring proper scaffolding and drug delivery systems. 相似文献
50.
Estelle Glais Vesna orevi Jelena Papan Bruno Viana Miroslav D. Dramianin 《RSC advances》2018,8(33):18341
MgTiO3 nanoparticles doped with Mn4+, with homogeneous size ranging about 63.1 ± 9.8 nm, were synthesized by a molten salt assisted sol gel method. These nanoparticles have been investigated as optical thermal sensors. The luminescence of tetravalent manganese ion in octahedral environment within the perovskite host presents drastic variations with temperature. Three different thermometry approaches have been proposed and characterized. Two luminescence intensity ratios are studied. Firstly between the two R-lines of Mn4+ emission at low temperature (−250 °C and −90 °C) with a maximal sensitivity of 0.9% °C−1, but also secondly between 2E → 4A2 (R-line) and the 4T2 → 4A2 transitions. This allows studying the temperature variation within a larger temperature range (−200 °C to 50 °C) with a sensitivity between 0.6% °C−1 and 1.2% °C−1 over this range. The last proposed method is the study of the lifetime variation versus temperature. The effective lifetime value corresponds to a combination of transitions from two excited energy levels of the tetravalent manganese (2E and 4T2) in thermal equilibrium toward the fundamental 4A2 state. Since the more energetic transition (4T2 → 4A2) is spin-allowed, contrary to the 2E → 4A2 one, the lifetime drastically decreases with the increase in temperature leading to an impressive high sensitivity value of 4.1% °C−1 at 4 °C and an exceptional temperature resolution of 0.025 °C. According to their optical features, MgTiO3:Mn4+ nanoparticles are indeed suitable candidates for the luminescence temperature probes at the nanoscale over several temperature ranges.Luminescence properties of MgTiO3 nanoparticles doped with Mn4+ ions are investigated for precise temperature determination. 相似文献