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131.
The rhizospheres of five different potato cultivars (including a genetically modified cultivar) obtained from a loamy sand
soil and two from a sandy peat soil, next to corresponding bulk soils, were studied with respect to their community structures
and potential function. For the former analyses, we performed bacterial 16S ribosomal RNA gene-based PCR denaturing gradient
gel electrophoresis (PCR-DGGE) on the basis of soil DNA; for the latter, we extracted microbial communities and subjected
these to analyses in phenotype arrays (PM1, PM2, and PM4, Biolog), with a focus on the use of different carbon, sulfur and
phosphorus sources. In addition, we performed bacterial PCR-DGGE on selected wells to assess the structures of these substrate-responsive
communities. Effects of soil type, the rhizosphere, and cultivar on the microbial community structures were clearly observed.
Soil type was the most determinative parameter shaping the functional communities, whereas the rhizosphere and cultivar type
also exerted an influence. However, no genetically modified plant effect was observed. The effects were imminent based on
general community analysis and also single-compound analysis. Utilization of some of the carbon and sulfur sources was specific
per cultivar, and different microbial communities were found as defined by cultivar. Thus, both soil and cultivar type shaped
the potato root-associated bacterial communities that were responsive to some of the substrates in phenotype arrays. 相似文献
132.
İpek Özcan Özlem Abacı Alev Haliki Uztan Buket Aksu Hayal Boyacıoğlu Tamer Güneri Özgen Özer 《AAPS PharmSciTech》2009,10(3):1024-1031
Chitosan-based carriers have important potential applications for the administration of drugs. In the present study, topical
gel formulations of terbinafine hydrochloride (T-HCl) were prepared using different types of chitosan at different molecular
weight, and the antifungal inhibitory activity was evaluated to suggest an effective formulation for the treatment of fungal
infections. The characteristics of gel formulations were determined with viscosity measurements and texture profile analysis.
Stability studies were performed at different temperatures during 3 months. The ex vivo permeation properties were studied through rat skin by using Franz diffusion cells. The antifungal inhibitory activity of
formulations on Candida species and filamentous fungi was also examined with agar-cup method. The microbiological assay was found suitable for determination
of in vitro antifungal activity of T-HCl. A marketed product was used to compare the results. The antifungal activity of T-HCl significantly
increased when it was introduced into the chitosan gels. A higher drug release and the highest zone of inhibition were obtained
from gels prepared with the lowest molecular weight chitosan (Protasan UP CL 213) compared to that of other chitosan gels
and marketed product. These results indicated the advantages of the suggested formulations for topical antifungal therapy
against Candida species and filamentous fungi. 相似文献
133.
İbrahim Esirden Muhammet Tanç Claudiu T. Supuran Muharrem Kaya 《Bioorganic & medicinal chemistry letters》2017,27(1):86-89
The synthesis of novel tetrazole/sulfonamide derivatives based on octahydroacridine, xanthene and chromene scaffold by using microwave (MW) assisted techniques is reported in this study. These synthesized hybrid compounds were assayed for the inhibition of carbonic anhydrase (CA, EC 4.2.1.1). The inhibitory activities were determined against three cytosolic human isoforms (hCA I, II and VII) and one membrane-associated (hCA IV) isoform. Some of the newly synthesized sulfonamides showed micromolar to nanomolar inhibitory activity against these enzymes. 相似文献
134.
Atmospheric pollen was collected with a Burkard sporetrap in Ankara, Turkey from January 1993 to January1994. The sum of the annual totals of the dailyconcentration of pollen, belonging to 44 taxa, was57,735. A relatively high pollen concentration wasrecorded in June which could be caused by higher windspeed and lower rainfall. Pinaceae,Cupressaceae/Taxaceae, Gramineae, Platanus, Populus,Moraceae, Chenopodiaceae/Amaranthaceae, Acer, Quercus,Betula, Salix, Rumex and Plantago are found tobe the dominant pollen types in the atmosphere inAnkara. 相似文献
135.
Ahmet ONAY Abdulselam ERTA Veysel SÜZERER smail YENER Mustafa Abdullah YILMAZ Emine AYAZ-TLKAT Remzi EKNC Nesrin BOZHAN Sevgi RTEGÜN-KANDEMR 《Turkish Journal of Biology》2021,45(4):570
To combat the coronaviruses and their novel variants, therapeutic drugs and the development of vaccines that are to be effective throughout human life are urgently needed. The endocannabinoid system (ECS) acts as a modulator in the activation of the microcirculation, immune system, and autonomic nervous system, along with controlling pharmacological functions such as emotional responses, homeostasis, motor functions, cognition, and motivation. The ECS contains endogenous cannabinoids, cannabinoid receptor (CBRs), and enzymes that regulate their biosynthesis, transport, and degradation. Moreover, phytocannabinoids and synthetic cannabinoids that mimic the action of endocannabinoids also play an essential role in the modulation of the ECS. Cannabinoids, the main constituents of cannabis (Cannabis sativa L.), are therapeutic compounds that have received international attention in the health field due to their therapeutic properties. Recently, they have been tested for the treatment of COVID-19 due to their antiviral properties. Indeed, cannabinoid-type compounds, and in particular cannabidiol (CBD), isolated from glandular trichomes found in the calyx of cannabis flowers with reported antiviral properties is hypothesized to be a therapeutic option in the ministration of SARS-CoV-2 consorted with COVID-19 disease. The relevant articles were determined from the database search published mainly in Web of Science, Google scholar, PubMed, Crossref, and ClinicalTrials.gov database during the pandemic period. The articles were evaluated for the therapeutic potentials, mechanisms of action of cannabinoids, the roles of the ECS in the immune system, impact of cannabinoids in SARS-CoV-2 septic, especially if they address the application of cannabinoids as drugs for the curability and management of SARS-CoV-2 and its novel variants. Although the evidence needed to be considered using cannabinoids in the control and treatment of viral diseases is currently in its infancy, they already offer an opportunity for clinicians due to their effects in relieving pain, improving appetite, and improving childhood epilepsy, especially in cancer and human immunodeficiency virus (HIV/AIDS) patients. In addition to these, the most recent scientific evidence emphasizes their use in the treatment of the coronavirus infected patients. In brief, all preclinic and clinic studies that have been reported show that, through the cannabinoid system, cannabinoids, particularly CBD, have many mechanisms that are effective in the treatment of patients infected by SARS-CoV-2. Thus, more extensive studies are necessary in this area to fully identify the effects of cannabinoids on SARS-CoV-2. 相似文献
136.
Sibel Yel İsmail Dursun Feyza Çetin Funda Baştuğ Sebahat Tülpar Ruhan Düşünsel 《Biomarkers》2018,23(6):558-562
Objective: Endothelial microparticles (EMPs) are considered as markers of endothelial dysfunction. In this study, we aimed to examine whether there is endothelial dysfunction in children with familial Mediterranean fever (FMF), hypothesizing that endothelial dysfunction would be present especially with acute-phase response in the active period of the disease.Methods: This cross-sectional study included 65 FMF patients (41 attack free, 24 attack period) and 35 healthy controls. Circulating EMPs, serum amyloid A (SAA), and other inflammation markers were measured in all groups. Circulating EMPs were measured using flow cytometry. Study groups were compared for circulating EMP and inflammatory markers. The relationship between EMPs and the activation of the disease was evaluated.Results: The levels of CD144+ and CD146+ EMPs in the FMF attack period group were significantly higher than those of the control group (p?0.05). The levels of inflammation markers in the attack period group were significantly higher than those of the control and attack-free groups (p?0.05). In the FMF attack group, the CD144+ and CD146+ EMP were significantly correlated with CRP.Conclusions: Our results suggest that endothelial damage is present especially in the active period of the disease in children with FMF. The endothelial dysfunction becomes an overt parallel with inflammation. 相似文献
137.
Two GTPase isoforms, Ypt31p and Ypt32p, are essential for Golgi function in yeast. 总被引:16,自引:3,他引:13 下载免费PDF全文
In eukaryotic cells, monomeric GTPases of the Ypt/Rab family function as regulators at defined steps of vesicular transport in exo- and endocytosis. Here we report on the isolation and characterization of two genes (YPT31 and YPT32) of the yeast Saccharomyces cerevisiae which encode members of the Ypt family exhibiting >80% sequence identity. Whereas the disruption of one of the two genes was phenotypically neutral, the disruption of both YPT31 and YPT32 led to lethality. Depletion of wild-type Ypt31p or of a short-lived ubiquitin-Ypt31p in a ypt32 null background led to a massive accumulation of Golgi-like membranes, an inhibition of invertase secretion and defects in vacuolar protein maturation. Similar alterations were observed in a conditional-lethal ypt31-1 mutant at 30 min after shift to the non-permissive temperature. According to subcellular fractionation, a significant part of Ypt31p appeared to be located in Golgi-enriched membrane fractions. In accordance with this, indirect immunofluorescence using affinity-purified anti-Ypt31p antibodies gave a punctate staining similar to that observed with Golgi-located proteins. From the phenotypic alterations observed in ypt31 and ypt32 mutants, it seems likely that the two GTPases are involved in intra-Golgi transport or in the formation of transport vesicles at the most distal Golgi compartment. 相似文献
138.
In this experimental study, the effect of cadmium on cold and restraint stress-induced gastric lesions has been studied. Rats
received 15 μg/mL cadmium-containing water for 30 d, and at the end of this period, they were subjected to cold and restraint
stress.
Cadmium accumulation in gastric mucosa was associated with increased mucosal lesions, as well as decreased mucin and PGE2 levels in rats exposed to cadmium. Stress-induced mucosal injury was more pronounced, and the hemoglobin leakage into gastric
lumen owing to breakdown in the barrier was 17.30±3.45 μg/mL in control and 35.71±6.18 μg/mL in treated rats. Our data suggest
that high cadmium intake facilitates the occurence of stress-induced mucosal lesions by diminishing the mucin content and
PGE2 generation in gastric mucosa. 相似文献
139.
İbrahim Hakkı Ciğerci Süleyman Cenkci Mustafa Kargıoğlu Muhsin Konuk 《Cytotechnology》2016,68(4):829-838
This study was undertaken to evaluate genotoxic potential of Thermopsis turcica aqueous extracts on the roots of onion bulb (Allium cepa L.) by comet assay and random amplified polymorphic DNA technique. The Allium root growth inhibition test indicated that the EC50 and 2×EC50 values were 8 and 16 mg/ml concentrations of T. turcica aqueous extracts, respectively. The negative control (distilled water), positive control (methyl methane sulfonate, 10 mg/l) and 8 and 16 mg/ml concentrations of T. turcica extracts were introduced to the roots of onion bulbs for 24 and 96 h. The root growth, DNA damage in root cells and randomly amplified polymorphic DNA (RAPD) profiles of root tissue were used as endpoints of the genotoxicity. The comet assay clearly indicated that dose-dependent single strand DNA breaks in the root nuclei of onions were determined for the treatment concentrations of T. turcica extracts. In comparison to RAPD profile of negative control group, RAPD polymorphisms became evident as disappearance and/or appearance of RAPD bands in treated roots. The diagnostic and phenetic numerical analyses of RAPD profiles obviously indicated dose-dependent genotoxicity induced by Thermopsis extracts. In conclusion, the results clearly indicated that water extract of T. turcica has genotoxic potential on the roots of onion bulbs as shown by comet assay and RAPD technique. 相似文献
140.
Three Turkish isolates of the entomopathogenic nematodes Steinernema carpocapsae, Steinernema feltiae and Heterorhabditis bacteriophora were evaluated under laboratory conditions (in different temperatures and doses) for their biocontrol efficiency against last instar Leptinotarsa decemlineata. Herein, the effects of infective juveniles in aqueous suspension against L. decemlineata were evaluated. S. feltiae appeared to be the most pathogenic nematode among the tested species. 相似文献