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21.
Conventional and microwave-assisted synthesis of ZnO nanorods have been performed with and without using PEG400. ZnO nanorods were synthesized with 50-250 nm of diameter which depends on the used surfactant and methods. Surfactant effects of PEG400 on the size and morphology of ZnO nanorods were investigated. The microwave method was compared to the conventional heating method. Morphologies were investigated by using scanning electron microscopy (SEM).  相似文献   
22.
The gene expression profile chip of salt-resistant wheat mutant RH8706-49 under salt stress was investigated. The overall length of the cDNA sequence of the probe was obtained using electronic cloning and RT-PCR. An unknown gene induced by salt was obtained, cloned, and named TaDi19 (Triticum aestivum drought-induced protein). No related report or research on the protein is available. qPCR analysis showed that gene expression was induced by many stresses, such as salt. Arabidopsis thaliana was genetically transferred using the overexpressing gene, which increased its salt tolerance. After salt stress, the transgenic plant demonstrated better physiological indicators (higher Ca2+ and lower Na+) than those of the wild-type plant. Results of non-invasive micro-test technology indicate that TaDi19-overexpressing A. thaliana significantly effluxed Na+ after salt treatment, whereas the wild-type plant influxed Na+. Chelating extracellular Ca2+ resulted in insignificant differences in salt tolerance between overexpressing and wild-type A. thaliana. Subcellular localization showed that the gene encoding protein was mainly located in the cell membrane and nucleus. TaDi19 was overexpressed in wild-type A. thaliana, and the transgenic lines were more salt-tolerant than the control A. thaliana. Thus, the wheat gene TaDi19 could increase the salt tolerance of A. thaliana.  相似文献   
23.
Plants are still to be explored for new anti-cancer compounds because overall success in cancer treatment is still not satisfactory. As a new possible source for such compounds, the lichens are recently taking a great attention. We, therefore, explored both the genotoxic and anti-growth properties of lichen species Parmelia sulcata Taylor. The chemical composition of P. sulcata was analyzed with comprehensive gas chromatography–time of flight mass spectrometry. Anti-growth effect was tested in human breast cancer cell lines (MCF-7 and MDA-MB-231) by the MTT and ATP viability assays, while the genotoxic activity was studied by assays for micronucleus, chromosomal aberration and DNA fragmentation in human lymphocytes culture. Cell death modes (apoptosis/necrosis) were morphologically assessed. P. sulcata inhibited the growth in a dose-dependent manner up to a dose of 100 μg/ml and induced caspase-independent apoptosis. It also showed genotoxic activity at doses (>125 μg/ml) higher than that required for apoptosis. These results suggest that P. sulcata may induce caspase-independent apoptotic cell death at lower doses, while it may be genotoxic at relatively higher doses.  相似文献   
24.
BACKGROUND: Urinary tract infection (UTI) may cause inflammation of the renal parenchyma and may lead to impairment in renal function and scar formation. Oxidant injury and reactive oxygen species (ROS) have been found responsible in the pathogenesis of UTI. The neurohypophyseal hormone oxytocin (OT) facilitates wound healing and is involved in the modulation of immune and inflammatory processes. We investigated the possible therapeutic effects of OT against Escherichia coli induced pyelonephritis in rats both in the acute and chronic setting. METHODS: Twenty-four Wistar rats were injected 0.1 ml solution containing E. coli ATCC 25922 10(10) colony forming units/ml into left renal medullae. Six rats were designed as sham group and were given 0.1 ml 0.9% NaCl. Pyelonephritic rats were treated with either saline or OT immediately after surgery and at daily intervals. Half of the pyelonephritic rats were decapitated at the 24th hour of E. coli infection, and the rest were followed for 7 days. Renal function tests (urea, creatinine), systemic inflammation markers [lactate dehydrogenase (LDH) and tumor necrosis factor alpha (TNF-alpha)] and renal tissue malondialdehyde (MDA) as an end product of lipid peroxidation, glutathione (GSH) as an antioxidant parameter and myeloperoxidase (MPO) as an indirect index of neutrophil infiltration were studied. RESULTS: Blood urea, creatinine, and TNF-alpha levels were increased, renal tissue MDA and MPO levels were elevated and GSH levels were decreased in both of the pyelonephritic (acute and chronic) rats. All of these parameters and elevation of LDH at the late phase were all reversed to normal levels by OT treatment. CONCLUSION: OT alleviates oxidant renal injury in pyelonephritic rats by its anti-oxidant actions and by preventing free radical damaging cascades that involves excessive infiltration of neutrophils.  相似文献   
25.
Bronchopulmonary dysplasia (BPD) continues to be a major cause of morbidity in premature infants. An imbalance between neutrophil elastase and its inhibitors has been implicated in BPD. Serine protease inhibitor (SERPIN)B1 is an inhibitor of neutrophil proteases, including neutrophil elastase (NE) and cathepsin G (cat G). Recent studies suggest that SERPINB1 could provide protection in the airways by regulating excess protease activity associated with inflammatory lung disorders. In this study, we determined the distribution and ontogeny of SERPINB1 in the baboon lung and characterized the expression of SERPINB1 in baboon models of BPD. SERPINB1 expression was detected in the conducting airway and glandular epithelial cells in addition to neutrophils, macrophages, and mast cells. SERPINB1 mRNA and protein expression increased with advancing gestational age and in the new BPD model. In contrast, SERPINB1 expression levels were decreased in the old BPD model. Furthermore, SERPINB1 was detected as a high-molecular-mass (HMM) complex in lung tissue and bronchoalveolar lavage fluid samples from the BPD group. Analysis of the HMM complex by coimmunoprecipitation showed that these complexes were formed between SERPINB1 and NE or cat G. High-performance liquid chromatography (HPLC) ion trap mass spectrometry verified the presence of SERPINB1 in HMM complexes. Finally, NE activity level was compared between new and old baboon models of BPD and was found to be significantly lower in new BPD. Thus SERPINB1 upregulation in new BPD may be protective by contributing to the regulation of neutrophil proteases NE and cat G.  相似文献   
26.
Comparative efficacy of oral spiramycin and ampicillin was estimated in the treatment of 65 children at the age of 5 to 12 years with infectious inflammatory diseases of the respiratory tract, tonsils and middle ear. By the 7th day of the treatment with spiramycin the cure was stated in 97.7 per cent of the patients and 2.3 per cent of the patients showed the improvement. With the use of ampicillin the cure was recorded only by the 12th day. Marked advantages of spiramycin were observed as well with respect to the time course of the improvement of the disease main signs such as fever, pain in the throat on swallowing, intoxication and others.  相似文献   
27.
Alendronate causes serious gastrointestinal adverse effects. The aim of this study was to investigate whether octreotide, a synthetic somatostatin analogue, improves the alendronate-induced gastric injury. Rats were administered 20mg/kg alendronate by gavage for 4 days, either alone or following treatment with octreotide (0.1 ng/kg, i.p.). On the last day, following drug administration, pilor ligation was performed and 2h later, rats were killed and stomachs were removed. Gastric acidity and tissue ulcer index values, lipid peroxidation (as assessed by malondialdehyde, MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity as well as the histologic appearance of the stomach tissues were determined. Chronic oral administration of alendronate induced significant gastric damage, increasing lipid peroxidation (37.1+/-3.2 nmol/g) and myeloperoxidase activity (57.6+/-3.7 U/g), while tissue glutathione levels (09.+/-0.1 micromol/g) decreased. Treatment with octreotide prevented this damage as well as the changes in biochemical parameters (MDA: 23.4+/-1.3 nmol/g; MPO: 31.68 U/g; GSH: 15.+/-0.1 micromol/g). Findings of the present study suggest that alendronate induces oxidative gastric damage by a local irritant effect, and that octreotide ameliorates this damage by inhibiting neutrophil infiltration and reducing lipid peroxidation. Therefore, its therapeutic role as a "ulcer healing" agent must be further elucidated in alendronate-induced gastric mucosal injury.  相似文献   
28.
We report on the synthesis by coupling of a triterpenoid oleanolic acid with 4'-diethylamino-3-hydroxyflavone (FE) to produce an environment-sensitive biomembrane probe with two-band ratiometric response in fluorescence emission. The synthesized compound (probe FOT) was tested in a series of model solvents and demonstrated the response to solvent polarity and intermolecular hydrogen bonding very similar to that of parent probe FE. Meantime when incorporated into lipid bilayer membranes, it showed new features differing in response between lipids of different surface charges as well as between glycerophospholipids and sphingomyelin. We observed that in the conditions of coexistence of rafts and non-raft structures the probe is excluded from the rafts.  相似文献   
29.
The authors assessed the in-hospital and long-term (up to 6 months) results of coronary stenting conducted just after diagnostic coronarography during a common procedure in patients with stable angina pectoris on effort. The 2001-2002 study included 2277 patients. The clinical indications for catheterization were Functional Classes II-IV stable angina on effort in 83 % of patients and silent ischemia in 17%. The study excluded patients with previous coronarography, acute coronary syndrome on admission, renal failure, left ventricular ejection fraction <30%, and left trunk stenosis. All the patients received aspirin and clopidogrel before catheterization. RESULTS: 57% of patients had multivessel disease; full revascularization was performed in 59% of the patients with multivessel disease. The coronary intervention was successful in 100% of cases. Significant in-hospital events (myocardial infarction without Q wave) were in 1.2% of cases. The mean length of hospital stay was 2.9 +/- 2.4 days. The rate of stent thrombosis for as long as 30 days was 0.2%. Recurrent angina and/or positive exercise tests were in 12% during 6 months. CONCLUSION: immediate stening is effective and safe in most patients with stable angina during diagnostic catheterization. It does not increase immediate and late complications.  相似文献   
30.
Corticosteroids, even in topical application, may cause immunosuppression and Cushing's syndrome. A case of disseminated fatal cytomegalovirus infection is reported in a 3-month-old girl with Cushing's syndrome caused by exogenous topical clobetasol propionate application, which might have caused immunosuppression due to prolonged use.  相似文献   
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