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91.
Metin DY Hilmioglu-Polat S Samlioglu P Doganay-Oflazoglu B Inci R Tumbay E 《Mycopathologia》2011,172(3):187-199
Candida species that show an increasing number of clinical and/or microbiological resistance to several antifungals and are the most
common agents of invasive fungal infections. The aim of this study was to investigate the in vitro susceptibility of Candida blood isolates to antifungal agents (amphotericin B, fluconazole, itraconazole, and voriconazole) by comparative use of the
CLSI reference microdilution method and Etest. Four hundred Candida blood isolates (215 Candida
albicans, 185 non-albicans
Candida strains) were included in the study. The broth microdilution test was performed according to the CLSI M27 A2 document. Etest
was carried out according to the manufacturer’s instructions. The MIC results obtained with reference microdilution were compared
with those obtained with the Etest by using percent and categorical agreements. According to MIK90 values, voriconazole was the most active and itraconazole was the least active drug in vitro against all Candida species. Other than voriconazole, statistically significant differences were found when the susceptibility of Candida albicans and non-albicans Candida spp. to amphotericin B, fluconazole, and itraconazole were compared. These antifungal agents were found to be more active
to C. albicans. Among the non-albicans
Candida species, the lowest MIC values were obtained for Candida parapsilosis isolates. When the standard method was compared with Etest, the total agreement was higher for C. albicans than for non-albicans species, especially for fluconazole and voriconazole. In view of the findings, it was concluded that itraconazole showed
the lowest activity against all Candida species. Etest could be an alternative method in assessing the in vitro antifungal susceptibility of Candida spp., but it is more convenient to use the microdilution method for studying in vitro susceptibility of non-albicans species, in particular for those possessing high MIC values against azoles. 相似文献
92.
93.
Tissue specialization at the metabolite level is perceived during the development of tomato fruit 总被引:4,自引:0,他引:4
Moco S Capanoglu E Tikunov Y Bino RJ Boyacioglu D Hall RD Vervoort J De Vos RC 《Journal of experimental botany》2007,58(15-16):4131-4146
Fruit maturation and tissue differentiation are important topics in plant physiology. These biological phenomena are accompanied by specific alterations in the biological system, such as differences in the type and concentration of metabolites. The secondary metabolism of tomato (Solanum lycopersicum) fruit was monitored by using liquid chromatography (LC) coupled to photo-diode array (PDA) detection, fluorescence detection (FD), and mass spectrometry (MS). Through this integrated approach different classes of compounds were analysed: carotenoids, xanthophylls, chlorophylls, tocopherols, ascorbic acid, flavonoids, phenolic acids, glycoalkaloids, saponins, and other glycosylated derivatives. Related metabolite profiles of peel and flesh were found between several commercial tomato cultivars indicating similar metabolite trends despite the genetic background. For a single tomato cultivar, metabolite profiles of different fruit tissues (vascular attachment region, columella and placenta, epidermis, pericarp, and jelly parenchyma) were examined at the green, breaker, turning, pink, and red stages of fruit development. Unrelated to the chemical nature of the metabolites, behavioural patterns could be assigned to specific ripening stages or tissues. These findings suggest spatio-temporal specificity in the accumulation of endogenous metabolites from tomato fruit. 相似文献
94.
A mechanistic understanding of the role of bone quality on fracture processes is essential for determining the underlying causes of age-related changes in the mechanical response of the human bone. In this study, a previously developed cohesive finite element model was used to investigate the effects of age-related changes and the orientation of crack growth on the toughening behavior of human cortical bone. The change in the anisotropy of toughening mechanisms with age was also studied. Finite element method (FEM) simulations showed that the initiation toughness decreased by 3% and 8%/decade for transverse and longitudinal crack growth, respectively. In contrast, fracture resistance curve slope for transverse and longitudinal crack growth decreased by 2% and 3%/decade, respectively. Initiation fracture toughness values were higher for the transverse than for the longitudinal for a given age. On the other hand, propagation fracture toughness values were higher for longitudinal than for transverse crack growth for a given age. With respect to age, the toughness ratio for crack initiation decreased by 6%/decade, but that for propagation showed almost no change (less than 1%). In light of these findings, an analytical model evaluating the crack arresting feature of cement lines, is proposed to explain the factors that determine crack penetration into osteons or its deflection by cement lines. 相似文献
95.
1. Glial cells are the most abundant cell population in the central nervous system. The aim of this study was to examine the
effects of melatonin, 7-nitroindazole, and riluzole on glutamate toxicity in primary glial cell culture.
2. Glutamate toxicity was induced by addition of 100 μM glutamate to the cultures, and then 100 μM melatonin, 500 μM 7-nitroindazole,
and 10 (M riluzole were administered in different groups. Lactate Dehydrogenase activity and nitrite levels were determined
at the 1st, 6th, and 24th h.
3. Melatonin, 7-nitroindazole, and riluzole decrease Lactate Dehydrogenase activity at the 1st, 6th, and 24th h (at all hours,
p<0.05). Nitrite levels were decreased by melatonin and riluzole at the 1st, 6th, and 24th h.
4. In this study, we observed that melatonin, 7-nitroindazole, and riluzole are effective as protective agents on glutamate
toxicity in mixed glial cells. 相似文献
96.
BACKGROUND: The hepatoid variant of yolk sac tumor (H-YST) is an exceedingly rare and highly malignant neoplasm. We present and discuss our experience with cytologic and histopathologic features of a mediastinal H-YST presenting with sternum metastasis, which to the best of our knowledge has not been previously reported. CASE: A 38-year-old man presented with a large mass on the sternum. Computed tomography of the thorax showed a large anterior mediastinal mass with sternum metastsis and multiple lung metastases. Laboratory examination revealed elevated serum alpha-fetoprotein (60,000 IU/mL). No tumor was found in the other organ systems. A percutaneous fine needle aspiration biopsy and subsequent open surgical biopsy were performed on the sternum metastasis. Cytologically, the tumor was composed of monotonous, large, round to polygonal hepatoid cells forming solid sheets and trabeculae entrapped with endothelial cells resembling hepatocellular carcinoma. Histopathologic sections of tumor showed tumor cells with eosinophilic to clear cytoplasm arranged in a solid, trabecular growth pattern, with some acinar formations. Immunohistochemical study supported the hepatoid origin. CONCLUSION: Fine needle aspiration cytology, together with the characteristic clinical presentations and specific tumor markers, is crucial to the initial diagnosis of H-YST. 相似文献
97.
The interaction of antidepressant drug trazodone hydrochloride (TRZ) with dipalmitoyl phosphatidylcholine (DPPC) multilamellar liposomes (MLVs) in the presence and absence of cholesterol (CHO) was investigated as a function of temperature by using Electron Paramagnetic Resonance (EPR) spin labeling, Fourier Transform Infrared (FTIR) Spectroscopy and Differential Scanning Calorimetry (DSC) techniques. These interactions were also examined for dimyristoyl phosphatidylcholine (DMPC) multilamellar liposomes by using Electron Paramagnetic Resonance (EPR) spin labeling technique. In the EPR spin labeling studies, 5- and 16-doxyl stearic acid (5-DS and 16-DS) spin labels were used to monitor the head group and alkyl chain region of phospholipids respectively. The results indicated that TRZ incorporation causes changes in the physical properties of PC liposomes by decreasing the main phase transition temperature, abolishing the pre-transition, broadening the phase transition profile, and disordering the system around the head group region. The interaction of TRZ with unilamellar (LUV) DPPC liposomes was also examined. The most pronounced effect of TRZ on DPPC LUVs was observed as the further decrease of main phase transition temperature in comparison with DPPC MLVs. The mentioned changes in lipid structure and dynamics caused by TRZ may modulate the biophysical activity of membrane associated receptors and in turn the pharmacological action of TRZ. 相似文献
98.
Ebru Cayir Aysegul Erdemir Ebru Ozkan Murat Topuzogullari Zeynep Busra Bolat Ayberk Akat Dilek Turgut-Balik 《Molecular biotechnology》2014,56(8):689-696
Tropical theileriosis is a disease caused by infection with an apicomplexan parasite, Theileria annulata, and giving rise to huge economic losses. In recent years, parasite resistance has been reported against the most effective antitheilerial drug used for the treatment of this disease. This emphasizes the need for alternative methods of treatment. Enolase is a key glycolytic enzyme and can be selected as a macromolecular target of therapy of tropical theileriosis. In this study, an intron sequence present in T. annulata enolase gene was removed by PCR-directed mutagenesis, and the gene was first cloned into pGEM-T Easy vector and then subcloned into pLATE31 vector, and expressed in Escherichia coli cells. The enzyme was purified by affinity chromatography using Ni–NTA agarose column. Steady-state kinetic parameters of the enzyme were determined using GraFit 3.0. High quantities (~65 mg/l of culture) of pure recombinant T. annulata enolase have been obtained in a higly purified form (>95 %). Homodimer form of purified protein was determined from the molecular weights obtained from a single band on SDS-PAGE (48 kDa) and from size exclusion chromatography (93 kDa). Enzyme kinetic measurements using 2-PGA as substrate gave a specific activity of ~40 U/mg, K m: 106 μM, kcat: 37 s?1, and k cat/K m: 3.5 × 105 M?1 s?1. These values have been determined for the first time from this parasite enzyme, and availability of large quantities of enolase enzyme will facilitate further kinetic and structural characterization toward design of new antitheilerial drugs. 相似文献
99.
Gizem Kursunluoglu Hulya Ayar Kayali Dilek Taskiran 《Cell biochemistry and biophysics》2014,69(3):707-716
Cisplatin accumulates in mitochondria, which is a potent and widely used chemotherapeutic agent. In order to clarify the potential effect of cisplatin on electron transport chain (ETC), the variation of succinate dehydrogenase (SDH) and cytochrome c oxidase (COX) enzyme activities, nucleotide levels, as well as catalase (CAT) enzyme and membrane lipid peroxidation (LPO) level with respect to liver and kidney of cisplatin-exposed rats were studied. We found that cisplatin caused significant impairment in the SDH, COX, and CAT activities, and nucleotide levels associated with membrane LPO in isolated mitochondria. It was determined whether capsaicin, as an antioxidant, has a possible protective role on all investigated parameters of liver and kidney induced by cisplatin. The results of capsaicin + cisplatin suggest that capsaicin have antioxidant capacity to scavenge ROS to prevent membrane damage. 相似文献
100.
Hakan Erdem Zeliha Kocak-Tufan Omer Yilmaz Zuhal Karakurt Aykut Cilli Hulya Turkan Ozlem Yazicioglu-Mocin Nalan Adıguzel Gokay Gungor Canturk Taşcı Gulden Yilmaz Oral Oncul Aygul Dogan-Celik Ozcan Erdemli Nefise Oztoprak Yakup Tomak Asuman Inan Demet Tok Sibel Temur Hafize Oksuz Ozgur Senturk Unase Buyukkocak Fatma Yilmaz-Karadag Derya Ozturk-Engin Dilek Ozcengiz Ahmet Karakas Hayati Bilgic Hakan Leblebicioglu 《Annals of clinical microbiology and antimicrobials》2014,13(1):1-5