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21.
Cultivated and wild Allium species were investigated in order to compare the antioxidant capacity of their leaves and bulbs. Leaf and bulb anti-oxidative
enzymes and scavenger activities, along with quantities of non-enzymic antioxidants, malonyl-dialdehyde and OH radicals were
determined. Results obtained suggest that leaves possess higher anti-oxidant and scavenging activities than bulbs in the majority
of cultivated and wild Allium species examined. Cultivation of some wild species such as A. flavum L., A. schoenoprasum L. and A. ursinum L. could be conducted in the future in order to produce Allium species with high antioxidant capacity in leaves and bulbs. 相似文献
22.
Drabek K van Ham M Stepanova T Draegestein K van Horssen R Sayas CL Akhmanova A Ten Hagen T Smits R Fodde R Grosveld F Galjart N 《Current biology : CB》2006,16(22):2259-2264
In motile fibroblasts, stable microtubules (MTs) are oriented toward the leading edge of cells. How these polarized MT arrays are established and maintained, and the cellular processes they control, have been the subject of many investigations. Several MT "plus-end-tracking proteins," or +TIPs, have been proposed to regulate selective MT stabilization, including the CLASPs, a complex of CLIP-170, IQGAP1, activated Cdc42 or Rac1, a complex of APC, EB1, and mDia1, and the actin-MT crosslinking factor ACF7. By using mouse embryonic fibroblasts (MEFs) in a wound-healing assay, we show here that CLASP2 is required for the formation of a stable, polarized MT array but that CLIP-170 and an APC-EB1 interaction are not essential. Persistent motility is also hampered in CLASP2-deficient MEFs. We find that ACF7 regulates cortical CLASP localization in HeLa cells, indicating it acts upstream of CLASP2. Fluorescence-based approaches show that GFP-CLASP2 is immobilized in a bimodal manner in regions near cell edges. Our results suggest that the regional immobilization of CLASP2 allows MT stabilization and promotes directionally persistent motility in fibroblasts. 相似文献
23.
Grinblat-Huse V Drabek EF Creasy HH Daugherty SC Jones KM Santana-Cruz I Tallon LJ Read TD Hatch TP Bavoil P Myers GS 《Journal of bacteriology》2011,193(15):4039-4040
Chlamydia psittaci is a highly prevalent avian pathogen and the cause of a potentially lethal zoonosis, causing life-threatening pneumonia in humans. We report the genome sequences of C. psittaci 6BC, the prototype strain of the species, and C. psittaci Cal10, a widely used laboratory strain. 相似文献
24.
Epilepsy is one of the most common neurological problems affecting approximately 1% of the world's population with higher incidence among elderly individuals. Although depression is a common comorbid condition in patients with epilepsy, there is a paucity of information regarding depression in geriatric patients with epilepsy. This study analysed a group of 83 patients affected by different epilepsy phenotypes accompanied by mental disorders, especially depression. Antiepileptic and antipsychotic drug treatment has been evaluated, particularly a positive effect of the new antiepileptics (monotherapy and polytherapy) both on the reduction of seizures and mental disorders. 相似文献
25.
Hranilovic D Blazevic S Ivica N Cicin-Sain L Oreskovic D 《Neurochemistry international》2011,59(2):202-207
Serotonin (5HT) is a biologically active amine present in mammals in the brain and the peripheral tissues. Autism is a neurodevelopmental disorder in which 5HT homeostasis is disturbed both centrally and peripherally, but the relationship between the 5HT disturbances in the two compartments is not understood. In an attempt to explore the relationship between the disturbed peripheral 5HT homeostasis and central 5HT functioning, we exposed the developing rat brain to increased 5HT concentrations, by treatment of rats with subcutaneous injections of the immediate 5HT precursor 5-hydroxy-l-tryptophan (5HTP, 25 mg/kg), or the non-selective MAO inhibitor tranylcypromine (TCP, 2 mg/kg), during the period of the most intensive development of 5HT neurons - from gestational day 13 to post-natal day 21. The effects of the mentioned treatments on peripheral and central 5HT levels were then studied in adult rats. Platelet and plasma 5HT concentrations (measured by ELISA), as well as cortical and midbrain 5HT, tryptophan and 5-hydroxyindoleacetic acid levels (measured by HPLC) were determined in twelve 5HTP treated and eight TCP treated rats, and compared with the values measured in 10 control, saline treated rats. Treatment with 5HTP significantly raised peripheral but not central 5HT concentrations. At adult age, peripheral 5HT homeostasis was re-established, while modest decrease in 5HT concentration was observed in frontal cortex, presumably due to hyperserotonemia-induced loss of 5HT terminals during brain development. Treatment with TCP induced significant 5HT elevations in both compartments. At adult age, permanent changes in 5HT homeostasis were observed, both peripherally (as hyperserotonemia) and centrally (as altered 5HT metabolism with decreased 5HT concentrations). Further studies are planned in order to explore the nature of the different disturbances of 5HT homeostasis induced by the two compounds, and their results are expected to shed some light on the role of hyperserotonemia in autism. 相似文献
26.
27.
Dr. Jelena Vukojević Dubravka Franić-Mihajlović Miroslav Mihaljčević 《Mycopathologia》1995,132(1):21-25
In trials with various agar media and autoclaved stem pieces of weeds and cultivated plants, perithecia ofDiaporthe helianthi Muntañola-Cvetkoviet al., developed only on autoclaved stem pieces. The simple, useful culture technique for producing perithecia is fully described. 相似文献
28.
Biodegradation of linear alkylbenzenesulphonates (LAS) by mixed methanotrophic-heterotrophic cultures 总被引:1,自引:0,他引:1
The biodegradation of undecylbenzenesulphonate (C11 LAS) was studied in shake flasks at 21°C using two mixed bacterial cultures. The first culture, MM1, contained a type II methanotroph and four heterotrophs, and was enriched from a groundwater aquifer. The second culture, MC, consisted of five heterotrophic strains, most of them belonging to the genus Pseudomonas , and was isolated from the wastewater of a detergent plant. Methane, carbon dioxide and oxygen concentrations were determined by gas chromatography. Concentrations of C11 LAS and the aromatic intermediates were determined by reversed-phase HPLC. In spite of faster transformation of the alkyl side-chain by the culture MC, the culture MM1 containing type II methanotroph was capable of further degradation of C11 LAS aromatic intermediates (sulphophenylalkanoates). The most probable mechanism for the degradation of the alkyl part of the C11 LAS molecule by both cultures was β-oxidation of the terminal methyl group followed by β-oxidation. Studies of methane utilization demonstrated an approximately three times higher second-order rate coefficient for methane consumption ( k max / K s ) in the absence of C11 LAS. This indicates a possible metabolic activity of methanotrophs in the transformation of the complex LAS molecule due to the methane monooxygenase enzyme system. 相似文献
29.
Ivana Čabarkapa Radmilo Čolović Olivera Đuragić Sanja Popović Bojana Kokić Dubravka Milanov 《Biofouling》2019,35(3):361-375
The aim of the present study was to determine the bioactive compounds in four essential oils (EO’s) from Origanum heracleoticum, Origanum vulgare, Thymus vulgaris and Thymus serpyllum and to assess their antimicrobial and anti-biofilm activity against Salmonella Enteritidis. Strains were previously characterized depending on the expression of the extracellular matrix components cellulose and curli fimbriae as rdar (red, dry and rough) and bdar morphotype (brown, dry and rough). This study revealed that the EO’s and EOC’s (carvacrol and thymol) investigated showed inhibition of biofilm formation at sub-minimum inhibitory concentration. Comparing the efficacy of EO’s and EOC’s in the inhibition of biofilm formation between the strains with different morphotype (rdar and bdar) did not show a statistically significant difference. Results related to the effectiveness of EO’s and EOC’s (the essential oil components, carvacrol and thymol) on eradication of preformed 48?h old biofilms indicated that biofilm reduction occurred in a dose-dependent manner over time. 相似文献
30.
Hirsl-Hećej V Pustisek N Sikanić-Dugić N Domljan LM Kani D 《Collegium antropologicum》2006,30(Z2):131-137
The study was undertaken to determine the prevalence of chlamydial genital infection in sexually active, urban adolescent females 15-19 years; to identify behavioral, demographic, and clinical factors associated with chlamydial infections; and to develop criteria for potential screening strategies. 500 adolescent women, median age 17.7 years, who visited gynecological outpatient clinic in Children's Hospital Zagreb for different reasons were enrolled in this study. Gynecological exam, colposcopy, detection of chlamydial infection by the rapid direct immunoassay of endocervical swab (Clearview Chlamydia-Unipath), endocervical cytological examination--Papanicolaou smear, and questionnaire to obtain demographic, social, behavioral and presence of symptoms data were performed. Positive Chlamydia trachomatis test were found in 16.4% of participants, cytologic cervical abnormalities--cervical intraepithelial neoplasia (CIN I-CIN III) were found in 25.2% and cytological signs of Human papilloma virus were found in 11.4%. Stepwise multivariate logistic regression analysis identified five factors associated with infection: the age of menarche < or =13 years, > or =4 lifetime sexual partners, non-use of contraception (rare or never), cervical friability, and abnormal Papanicolaou test. Urban adolescent sexually active women are at high risk for chlamydial infection and other sexually transmitted diseases including HIV infection. Association between chlamydial genital infection and risk-taking sexual and contraceptive behavior was found. Routine Chlamydia trachomatis testing for this population is recommended as well as implementation of school based sexual health education because of their risk-taking sexual behavior. 相似文献