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51.
S. Özmen Toğay A. Çelebi Keskin L. Açık A. Temiz 《Journal of applied microbiology》2010,109(3):1084-1092
Aim: To determine the virulence genes, antibiotic resistance and plasmid profiles of 16 Enterococcus faecium and 68 Enterococcus faecalis strains isolated from various naturally fermented foods. Methods and Results: The presence of virulence genes (agg2, gelE, cylM, cylB, cylA, espfs, espfm, efaAfs, efaAfm, cpd, cop, ccf, cad) and also the genes vanA and vanB were investigated by polymerase chain reaction (PCR). Antibiotic resistance of the isolates was determined by disc diffusion method. Most of the tested isolates were positive for virulence genes and resistant to some antibiotics. One of the Ent. faecalis strains isolated from a cheese sample carried the vanA gene and was intermediately resistant to vancomycin. The strains usually contained large plasmids, which might harbour acquired antibiotic resistance. Conclusion: The study showed that Ent. faecium and Ent. faecalis strains isolated from naturally fermented Turkish foods may be potential risk factors for consumer health in terms of virulence genes and acquired antibiotic resistance. Significance and Impact of the Study: The results indicate the importance of enterococcal contamination in terms of the safety of some fermented Turkish foods. 相似文献
52.
Oral A Tarakçi D Dişçi R 《Journal of strength and conditioning research / National Strength & Conditioning Association》2006,20(3):572-578
The aim of this study was to assess the bone status of dancers using calcaneal quantitative ultrasound (QUS). Twenty-four male and 26 female dancers (aged 19-36 years) and 100 age- and sex-matched nonathletic controls were included in this study. QUS parameters (broadband ultrasound attenuation [BUA], speed of sound [SOS], quantitative ultrasound index [QUI], and estimated heel bone mineral density [eBMD]) were obtained for both heels in all subjects using a gel-coupled QUS device. Two-way analysis of variance, including the factors of dancing status and gender, revealed significant differences in all QUS parameters between the dancers and the controls (p < 0.001 for all), without a significant interaction with gender status. For each heel (right versus left), the mean QUI, BUA, SOS, and eBMD values of the male and female dancers were 22.0% vs. 20.9% and 16.6% vs. 16.0%; 21.6% vs. 24.1% and 13.2% vs. 14.3%; 2.3% vs. 2.0% and 1.7% vs. 1.7%; and 25.0% vs. 23.9% and 19.0% vs. 18.6% higher than those of the male and female controls, respectively. Analysis of covariance still revealed significant differences between the dancers and the controls after controlling for the influence of body mass index (p < 0.001). Furthermore, the finding that significant bilateral differences in BUA did exist in the controls but not in the dancers demonstrated site-specific effects of exercise on bone, indicating that it is the dance that improved bone properties. Calcaneal QUS, with a strong discriminative ability between those involved in professional dance and normally active individuals, emerges as an attractive technology for exploring the benefits of exercise on bone, which might be a challenge for those in the conditioning field, who need to identify those who need intervention in terms of bone status and promote participation in high-impact physical activity, such as dance, to enhance bone quality. 相似文献
53.
Reaction of 2 equiv. amount of copper(II) chloride dihydrate with 2 equiv. of methyl-5-methyl-1-(4,6-dimethyl-2-pyrimidyl)pyrazole-3-carboxylate (DpymPzC) in presence of 1 equiv. of 2-mercapto-4,6-dimethylpyrimidine (DpymtH) at pH ∼ 6 afforded the tricoordinated copper(I) complex [Cu(DpymPzC)Cl] (1). The same reaction with copper(II) perchlorate hexahydrate, as the metal salt under the same equivalent ratio at pH ∼ 6 formed the tetracoordinated copper(I) complex [Cu(DpymPzC)2]ClO4 (2). In both the cases, the role of DpymtH is nothing but only to reduce the copper(II) salt in situ finally forming the copper(I) complex. On the other hand, the direct reaction between the copper(I) thiocyanate and DpymPzC in 2:2 equiv. ratio produced a tricoordinated copper(I) complex [Cu(DpymPzC)SCN] (3). In a similar reaction of 2 equiv. amount of copper(II) chloride dihydrate with 2 equiv. amount of ethyl-5-methyl-1-(2-pyridyl)pyrazole-3-carboxylate (PyPzC) in presence of 1 equiv. of DpymtH at pH ∼ 6, an intense red coloured microcrystalline compound (4) was obtained. In contrast, 1 equiv. of PyPzC and 2 equiv. of DpymtH on reaction with 1 equiv. of copper(II) chloride dihydrate at pH ∼ 6 produced a novel tetranuclear mixed coordinated [Cu4(DpymtH)4Cl4] complex (5). Here DpymtH plays dual role - a reducing agent for the copper(II) salt followed by a chelating ligand towards copper(I) so formed in situ. Among the above species, 1, 2 and 5 are crystallographically characterized. In 1, the central copper atom is in distorted triangular planar geometry with N2Cl chromophore whereas in 2, the same is in distorted tetrahedral geometry with N4 chromophore. Notably, the extent of distortion from the ideal geometry is more in 2. In 5, which is in chair conformation, out of four copper atoms, two being in S2Cl chromophore are tricoordinated and the remaining two are tetracoordinated with NS2Cl chromophore. The metal centers are bridged through DpymtH in its ‘thione’ form. Interestingly, the chelation (in part) results in formation of the highly stable four-membered two chelate rings around the two tetracoordinated copper atoms in 5. The two copper centers along the long arm of the chair are separated through a distance of 5.190 Å while those in the short arm are at a length of 3.629 Å. The electronic, IR spectra and electrochemistry of the complexes 1, 2 and 5 have also been investigated. 相似文献
54.
Tarak Srivastava Ellen T. McCarthy Ram Sharma Patricia A. Cudmore Mukut Sharma Mark L. Johnson Lynda F. Bonewald 《Journal of cell communication and signaling》2010,4(2):79-90
Podocytes play a key role in maintaining and modulating the filtration barrier of the glomerulus. Because of their location, podocytes are exposed to mechanical strain in the form of fluid flow shear stress (FFSS). Several human diseases are characterized by glomerular hyperfiltration, such as diabetes mellitus and hypertension. The response of podocytes to FFSS at physiological or pathological levels is not known. We exposed cultured podocytes to FFSS, and studied changes in actin cytoskeleton, prostaglandin E2 (PGE2) production and expression of cyclooxygenase-1 and–2 (COX-1, COX-2). FFSS caused a reduction in transversal F-actin stress filaments and the appearance of cortical actin network in the early recovery period. Cells exhibited a pattern similar to control state by 24 h following FFSS without significant loss of podocytes or apoptosis. FFSS caused increased levels of PGE2 as early as 30 min after onset of shear stress, levels that increased over time. PGE2 production by podocytes at post-2 h and post-24 h was also significantly increased compared to control cells (p < 0.039 and 0.012, respectively). Intracellular PGE2 synthesis and expression of COX-2 was increased at post-2 h following FFSS. The expression of COX-1 mRNA was unchanged. We conclude that podocytes are sensitive and responsive to FFSS, exhibiting morphological and physiological changes. We believe that PGE2 plays an important role in mechanoperception in podocytes. 相似文献
55.
Tak Fung Ryan A. Chisholm Kristina Anderson‐Teixeira Norm Bourg Warren Y. Brockelman Sarayudh Bunyavejchewin Chia‐Hao Chang‐Yang Rutuja Chitra‐Tarak George Chuyong Richard Condit Handanakere S. Dattaraja Stuart J. Davies Corneille E. N. Ewango Gary Fewless Christine Fletcher C. V. Savitri Gunatilleke I. A. U. Nimal Gunatilleke Zhanqing Hao J. Aaron Hogan Robert Howe Chang‐Fu Hsieh David Kenfack YiChing Lin Keping Ma Jean‐Remy Makana Sean McMahon William J. McShea Xiangcheng Mi Anuttara Nathalang Perry S. Ong Geoffrey Parker E‐Ping Rau Jessica Shue Sheng‐Hsin Su Raman Sukumar I‐Fang Sun Hebbalalu S. Suresh Sylvester Tan Duncan Thomas Jill Thompson Renato Valencia Martha I. Vallejo Xugao Wang Yunquan Wang Pushpa Wijekoon Amy Wolf Sandra Yap Jess Zimmerman 《Ecology letters》2020,23(1):160-171
Among the local processes that determine species diversity in ecological communities, fluctuation‐dependent mechanisms that are mediated by temporal variability in the abundances of species populations have received significant attention. Higher temporal variability in the abundances of species populations can increase the strength of temporal niche partitioning but can also increase the risk of species extinctions, such that the net effect on species coexistence is not clear. We quantified this temporal population variability for tree species in 21 large forest plots and found much greater variability for higher latitude plots with fewer tree species. A fitted mechanistic model showed that among the forest plots, the net effect of temporal population variability on tree species coexistence was usually negative, but sometimes positive or negligible. Therefore, our results suggest that temporal variability in the abundances of species populations has no clear negative or positive contribution to the latitudinal gradient in tree species richness. 相似文献
56.
Enhancing Science Teaching through Performing Marbling Art Using Basic Solutions and Base Indicators
Emine Çil Kevser Çelik Tuba Maçın Gülay Demirbaş Özlem Gökçimen 《Science activities》2013,50(4):136-145
Basic solutions are an indispensable part of our daily life. Basic solutions are commonly used in industries such as the textile industry, oil refineries, the fertilizer industry, and pharmaceutical products. Most cleaning agents, such as soap, detergent, and bleach, and some of our foods, such as chocolate and eggs, include bases. Bases are the fundamental concepts of chemistry. Indicators are chemical compounds that can be added to solution to determine whether it is a base or not. This article describes an activity whose primary aim is to teach base indicators to preservice elementary teachers. In this activity, the authors turned the traditional art of marbling into something achievable with the chemical substances that are the basic solutions and base indicators found in nearly all chemistry laboratories. Therefore, this activity can be called chemical marbling. The preservice elementary teachers learned the base indicators and basic solutions throughout this activity. The purpose of the study is not only to teach the science concepts to the preservice elementary teachers with fun but also to promote the development of their attitudes toward science, creativity, and aesthetic feelings. Suggestions stress that chemical marbling might be a good tool to acquire the preservice elementary teachers’ cognitive and affective learning outcomes. 相似文献
57.
Hatice Yorulmaz Fatma Burcu Şeker Göksel Demir İbrahim Ertuğrul Yalçın Baria Öztaş 《Biological trace element research》2013,151(2):256-262
We evaluated the effect of zinc treatment on the blood–brain barrier (BBB) permeability and the levels of zinc (Zn), natrium (Na), magnesium (Mg), and copper (Cu) in the brain tissue during epileptic seizures. The Wistar albino rats were divided into four groups, each as follows: (1) control group, (2) pentylenetetrazole (PTZ) group: rats treated with PTZ to induce seizures, (3) Zn group: rats treated with ZnCl2 added to drinking water for 2 months, and (4) Zn?+?PTZ group. The brains were divided into left, right hemispheres, and cerebellum?+?brain stem regions. Evans blue was used as BBB tracer. Element concentrations were analyzed by inductively coupled plasma optical emission spectroscopy. The BBB permeability has been found to be increased in all experimental groups (p?<?0.05). Zn concentrations in all brain regions in Zn-supplemented groups (p?<?0.05) showed an increase. BBB permeability and Zn level in cerebellum?+?brain stem region were significantly high compared to cerebral hemispheres (p?<?0.05). In all experimental groups, Cu concentration decreased, whereas Na concentrations showed an increase (p?<?0.05). Mg content in all the brain regions decreased in the Zn group and Zn?+?PTZ groups compared to other groups (p?<?0.001). We also found that all elements’ levels showed hemispheric differences in all groups. During convulsions, Zn treatment did not show any protective effect on BBB permeability. Chronic Zn treatment decreased Mg and Cu concentration and increased Na levels in the brain tissue. Our results indicated that Zn treatment showed proconvulsant activity and increased BBB permeability, possibly changing prooxidant/antioxidant balance and neuronal excitability during seizures. 相似文献
58.
59.
Aksu Neslihan Samadi Afshin Yalçınkaya Ahmet Çetin Tuğçe Eser Burcu Lay İncilay Öziş Türkan Nadir Öztaş Yeşim Sabuncuoğlu Suna 《Molecular and cellular biochemistry》2020,466(1-2):117-128
Molecular and Cellular Biochemistry - Aberrant structural formations of Cu/Zn superoxide dismutase enzyme (SOD1) are the probable mechanism by which circumscribed mutations in the SOD1 gene cause... 相似文献
60.
Boric acid and sodium borates have been considered as being “toxic to reproduction and development”, following results of animal studies with high doses. However unfavorable effects of boron exposure on reproduction and development have not been proved in epidemiological studies so far. The aim of the present study was to investigate the reproductive toxicity indicators in highly exposed workers employed in a boric acid production plant in Band?rma, Turkey. Two hundred and four workers participated in this study. The mean blood boron concentration of the high exposure group of workers was 223.89 ± 69.49 (152.82–454.02) ng/g. Unfavorable effects of boron exposure on the reproductive toxicity indicators were not observed. 相似文献