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Full-Text Articles in Entire DC Network
Synthesis Of New Antimicrobial Agents; Amide Derivatives Of Pyranones And Pyridinones, Mutlu Di̇lsi̇z Aytemi̇r, Robert C. Hider, Di̇lek Demi̇r Erol, Meral Özalp, Meli̇ke Eki̇zoğlu
Synthesis Of New Antimicrobial Agents; Amide Derivatives Of Pyranones And Pyridinones, Mutlu Di̇lsi̇z Aytemi̇r, Robert C. Hider, Di̇lek Demi̇r Erol, Meral Özalp, Meli̇ke Eki̇zoğlu
Turkish Journal of Chemistry
In this study, 4(1H)-pyridinones with an amide function in Position 2 of the pyridinone ring showed antimicrobial activity. The synthesis and the biological properties of some novel amide derivatives of pyran-4(1H)-one and 4(1H)-pyridinone have been reported. Amide derivatives of pyran-4(1H)-one and 4(1H)-pyridinone were prepared using two different methods. Antimicrobial activities were determined as MIC values using the microdilution broth method against the bacteria Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa and the fungi Candida albicans, Candida krusei and Candida parapsilosis. Compounds 6 and 9 exhibited the best inhibitor activity against S. aureus.
The Role Of Eicosanoids On Nodulation Reactions To Bacterium Serratia Marcescens In Larvae Of Ostrinia Nubilalis, Hasan Tunaz, Ali̇ Arda Işikber, Mehmet Kubi̇lay Er
The Role Of Eicosanoids On Nodulation Reactions To Bacterium Serratia Marcescens In Larvae Of Ostrinia Nubilalis, Hasan Tunaz, Ali̇ Arda Işikber, Mehmet Kubi̇lay Er
Turkish Journal of Agriculture and Forestry
Nodulation is the first step of the cellular defense reactions to bacterial infections in insects. In the present study, injecting larvae of the European corn borer, Ostrinia nubilalis, with eicosanoid biosynthesis inhibitors, immediately prior to intrahemocoelic injections of the bacterium, Serratia marcescens, sharply reduced the nodulation response to bacterial challenges. Separate treatments with specific inhibitors including dexamethasone (a phospholipase A_2 inhibitor), indomethacin (a cyclooxygenase inhibitor) and phenidone (a dual cyclooxgenase/lipoxygenase inhibitor) also impaired the ability of European corn borers to form nodules in reaction to bacterial challenges. The inhibitory influence of phenidone was apparent within 30 mins after infection, and …
Peritoneal Defense Mechanisms, Toni̇ Hau
Peritoneal Defense Mechanisms, Toni̇ Hau
Turkish Journal of Medical Sciences
No abstract provided.
Drug Resistance In Acute Leukaemia And Reversion, Jean-Pierre Marie, Ollivier Legrand
Drug Resistance In Acute Leukaemia And Reversion, Jean-Pierre Marie, Ollivier Legrand
Turkish Journal of Medical Sciences
No abstract provided.
Melatonin Implants Have No Effect On The Testis Volume And Body Weight In Mongolian Gerbils, Alper Karakaş, Bülent Gündüz
Melatonin Implants Have No Effect On The Testis Volume And Body Weight In Mongolian Gerbils, Alper Karakaş, Bülent Gündüz
Turkish Journal of Biology
Photoperiod is an important environmental cue in the regulation of reproductive activity in Mongolian gerbils. Photoperiodic information is ultimately transduced into a hormonal signal by the pineal gland. We examined the effect of constant-release melatonin capsules on the testicular size and body weights of male Mongolian gerbils exposed to a long (14L: 10D) photoperiod. Three groups were formed: control (n = 10), intact + melatonin implant (n = 10) and pinealectomy + melatonin implant (n = 10). The testes and body weights of the gerbils were recorded every week for 8 weeks. Body weights (76 ± 2.0 g intact + …
Host Finding Behavior Of Two Different Turkish Isolates Of Entomopathogenic Nematode Species, Heterorhabditis Bacteriophora, Poinar 1976 (Rhabditida: Heterorhabditidae), İ. Alper Susurluk, Işik O. Ünlü, İlker Kepenekci̇
Host Finding Behavior Of Two Different Turkish Isolates Of Entomopathogenic Nematode Species, Heterorhabditis Bacteriophora, Poinar 1976 (Rhabditida: Heterorhabditidae), İ. Alper Susurluk, Işik O. Ünlü, İlker Kepenekci̇
Turkish Journal of Biology
The movement of 2 different isolates of an insect parasitic nematode species (Heterorhabditis bacteriophora Tur-H2 and H. bacteriophora Tur-H1) in vertical columns was tested under laboratory conditions. We have found significant differences in the movements of H. bacteriophora Tur-H2 and H. bacteriophora Tur-H1 towards the Galleria mellonella larvae as a host. The maximum nematode infection rate inside the host was observed on the third day of the trial period for both species. We have recorded the number and the given percentage of infective juveniles (IJs) of H. bacteriophora Tur-H2 that moved towards the G. mellonella larvae within 24, 48, 72, …
Entomopathogenic Nematodes (Steinernematidae And Heterorhabditidae) For Biological Control Of Soil Pests, Selçuk Hazir, Harry K. Kaya, S. Patricia Stock, Nevi̇n Keski̇n
Entomopathogenic Nematodes (Steinernematidae And Heterorhabditidae) For Biological Control Of Soil Pests, Selçuk Hazir, Harry K. Kaya, S. Patricia Stock, Nevi̇n Keski̇n
Turkish Journal of Biology
Several species of entomopathogenic nematodes in the families Steinernematidae (Steinernema) and Heterorhabditidae (Heterorhabditis) are being produced commercially and used as biological control agents against many soil insect pests and insects in cryptic habitats in many parts of the world. These nematodes, which are mutualistically associated with bacteria (Steinernema with Xenorhabdus bacteria and Heterorhabditis with Photorhabdus bacteria), offer a number of advantages because they have a broad host range, kill their hosts within 48 h, can be easily produced in vivo and in vitro, can be applied with standard spray equipment, are safe to humans and other non-target organisms, have no …
Antimicrobial Activity Of Viscum Album L. Subsp. Abietis (Wiesb), Ömer Ertürk, Hati̇ce Kati, Nuretti̇n Yayli, Zi̇hni̇ Demi̇rbağ
Antimicrobial Activity Of Viscum Album L. Subsp. Abietis (Wiesb), Ömer Ertürk, Hati̇ce Kati, Nuretti̇n Yayli, Zi̇hni̇ Demi̇rbağ
Turkish Journal of Biology
Viscum album L. subsp. abietis (Wiesb.) (Loranthaceae) is extensively used for treatment in traditional medicine. This plant was collected in the region of Artvin, northern Turkey. Different concentrations of n-hexane extract were tested using the agar diffusion technique against 6 bacteria (Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Enterobacter cloacae and Proteus vulgaris), and 1 fungus (Candida albicans). We determined that fractions 6 and 7 of n-hexane extract of V. album subsp. abietis showed antimicrobial activity against the micro-organisms tested.
Isolation Of Trichoderma Spp. And Determination Of Their Antifungal, Biochemical And Physiological Features, Çi̇ğdem Küçük, Meri̇h Kivanç
Isolation Of Trichoderma Spp. And Determination Of Their Antifungal, Biochemical And Physiological Features, Çi̇ğdem Küçük, Meri̇h Kivanç
Turkish Journal of Biology
It is well known that Trichoderma spp. can be used as a biological control agent. In this study, Trichoderma isolates were obtained from 31 different Eskisehir soil samples. The biocontrol and antifungal effects of these isolates against various plant pathogen fungi were determined. We found that all filtrates of Trichoderma harzianum T9, T10, T15 and T19 were effective against plant pathogens Fusarium culmarum, F. oxysporum, F. moniliforme, Rhizoctonia solani, Sclerotium rolfsii, Gaeumannomyces graminis var. tritici and Drechslera sorokiniana. Among these isolates, T. harzianum T19 showed a wide range of inhibitory effects on plant pathogens. F. oxysporum was found to be …
Analysis Of The Effects Of Transcription Factors Gcr2p And Sgc1p On The Control Of The Suc2 Gene Expression In Saccharomyces Cerevisiae, Sezai̇ Türkel, Tülay Turgut, İpek Savaşçioğlu
Analysis Of The Effects Of Transcription Factors Gcr2p And Sgc1p On The Control Of The Suc2 Gene Expression In Saccharomyces Cerevisiae, Sezai̇ Türkel, Tülay Turgut, İpek Savaşçioğlu
Turkish Journal of Biology
The transcription of the SUC2 gene is regulated by glucose repression and the derepression mechanism in the yeast Saccharomyces cerevisiae. The Mig1p-Tup1p-Ssn6p repressor complex, hexokinase PII and nucleosomes are required for the repression of the SUC2 gene. The Snf/Swi and SAGA complexes act on Mig1p and nucleosomes in low glucose media. SUC2 transcription thus becomes activated. In this study, it is shown that the transcription factors Gcr2p and Sgc1p are also required for the high level transcription of the SUC2 gene. SUC2 transcription and the invertase synthesis decreased at significant levels in gcr2 and sgc1 mutant yeast cells. In addition, …
Selection Of Chickpea (Cicer Arietinum L.) Genotypes For Resistance To Ascochyta Blight [Ascochyta Rabiei (Pass.) Labr.], Yield And Yield Criteria, Cengi̇z Toker, Hüseyi̇n Çanci
Selection Of Chickpea (Cicer Arietinum L.) Genotypes For Resistance To Ascochyta Blight [Ascochyta Rabiei (Pass.) Labr.], Yield And Yield Criteria, Cengi̇z Toker, Hüseyi̇n Çanci
Turkish Journal of Agriculture and Forestry
Ascochyta blight, caused by Ascochyta rabiei (Pass.) Lab., is the most important disease in the chickpea (Cicer arietinum L.) in many countries, including Turkey. Efforts to control the disease were made using host-plant resistance as the most efficient and economical way. A total of 41 exotic genotypes were evaluated for resistance to A. rabiei and also yield and yield criteria near Antalya in the west Mediterranean region of Turkey in the 2000-2001 and 2001-2002 seasons. After every 2 test lines, the susceptible check ILC 263 was sown. When the susceptible check was completely killed by ascochyta blight, blight severity was …
The Analysis Of Partial Dominance Of Intragenic Mutations At The Adh Locus In Drosophila Melanogaster At Two Different Alcohol Concentrations, Vatan Taşkin
Turkish Journal of Biology
The dominance of a de novo mutation determines its effect on the viability of the first and succeeding generations; therefore, it is a major factor in estimating the risk from mutations to human health. It is well established that large deletions lead to significant dominance, but until the recent development of molecular methods for amplification and sequencing of mutations it was not possible to determine the dominance of specific intragenic changes in DNA. The purpose of this study was to determine the dominance for a series of Adh-null mutations, each with a minimum mutation of a transition at one base …
Voltammetric And Flow Injection Amperometric Determination Of Cysteine At A Glassy Carbon Electrode In The Presence Of Copper(Ii) Ions, Zekerya Dursun, İlyas Şahbaz, F. Ni̇l Ertaş, Gürel Ni̇şli̇
Voltammetric And Flow Injection Amperometric Determination Of Cysteine At A Glassy Carbon Electrode In The Presence Of Copper(Ii) Ions, Zekerya Dursun, İlyas Şahbaz, F. Ni̇l Ertaş, Gürel Ni̇şli̇
Turkish Journal of Chemistry
The voltammetric behaviour of cysteine was investigated in the presence of Cu(II) ions at a rotating glassy carbon electrode (RGCE). Two reduction peaks related to the successive reduction of the cysteine complexes of Cu(II) and Cu(I) ions were observed at --0.30 and --0.60 V vs. SCE respectively. These peaks were increased upon the addition of cysteine into a pH 9.20 borate buffer solution containing 0.1 M KNO_{3} and 1.0 x 10^{-5} M Cu(II) ions. The calibration curve was linear in the concentration range of 5.0 x 10^{-10}- 2.0 x 10^{-8} M for cysteine by utilising the peak current at --0.6 …
Electrofusion Of Saccharomyces Cerevisiae Auxotrophic Mutants Of Identical Mating Type Using A Laboratory-Made System, Gökhan Coral, Ömer Çolak, M. Ni̇sa Ünaldi, Burhan Arikan
Electrofusion Of Saccharomyces Cerevisiae Auxotrophic Mutants Of Identical Mating Type Using A Laboratory-Made System, Gökhan Coral, Ömer Çolak, M. Ni̇sa Ünaldi, Burhan Arikan
Turkish Journal of Biology
Yeast protoplasts from haploid auxotroph strains DC6 (MAT\alpha) and FY73 (MAT\alpha) were exposed to an inhomogeneous alternating field (AC 200 V/cm). Due to the dielectrophoretic aggregation two or more cells with close membrane contact were formed between the two electrodes. The effects of different DC pulses were investigated to determine critical fusogenic pulse strength. In the results, the maximum fusant cells were obtained only when 8 kV field strengths were applied. These findings showed that the optimum fusogenic pulse strength for yeast protoplasts is 8 kV/cm under our experimental conditions. After fusion, the DNA contents of both hybrid and individual …
Extremely Halophilic Bacterial Communities In Şereflikoçhisar Salt Lake In Turkey, Meral Bi̇rbi̇r, Cenk Sesal
Extremely Halophilic Bacterial Communities In Şereflikoçhisar Salt Lake In Turkey, Meral Bi̇rbi̇r, Cenk Sesal
Turkish Journal of Biology
Şereflikoçhisar Lake is the largest salt lake in central Turkey. This lake is a major source of solar salt for food, hide and other industries locally. Due to the economic importance of salt obtained from this lake, a microbial survey has been conducted. Six salt and three brine samples were obtained from the lake for physico-chemical and microbiological analyses. Physico-chemical analysis showed that the salts and brines contain sufficient ions and hardness to support extremely halophilic bacteria. The salt collected from the lake contained 10^4-10^6 colony-forming units of extremely halophilic bacteria per gram and brine taken from the lake contained …
Biosorption Of Copper Ions By Caustic Treated Waste Baker's Yeast Biomass, Yekta Göksungur, Si̇bel Üren, Ulgar Güvenç
Biosorption Of Copper Ions By Caustic Treated Waste Baker's Yeast Biomass, Yekta Göksungur, Si̇bel Üren, Ulgar Güvenç
Turkish Journal of Biology
Waste baker's yeast (Saccharomyces cerevisiae) was used as a biosorbent for Cu^{+2} biosorption. The yeast cells were treated with caustic soda, ethanol and heat to increase their biosorption capacity. Among the treatment methods used, the highest copper uptake (21.1 mg g^{-1}) was obtained with the caustic treatment of baker's yeast. The effect of initial copper concentration and pH on biosorption for caustic treated yeast was studied. The highest Cu^{+2} uptake (120.7 mg g^{-1}) was obtained at pH 4.0, for 198.2 mg I^{-1} initial copper ion concentration. The Langmuir model and Freundlich equation were applied to the experimental data and the …
Protein And Dna In Systematic Biology, Selma Gülbi̇tti̇ Onarici, Si̇bel Sümer
Protein And Dna In Systematic Biology, Selma Gülbi̇tti̇ Onarici, Si̇bel Sümer
Turkish Journal of Biology
Since the 1960s, biological macromolecules have occupied an increasingly important role in evolutionary and systematic studies. These biological macromolecules, used as sources of molecular characteristics, are proteins and various types of DNA such as a nuclear genome, nuclear ribosomal DNA, mitochondrial genome, and chloroplast genome. Electrophoresis and immunological techniques are used for generating systematic data from proteins. Generally, electrophoretic methods focus on two general forms of protein data, isozymes and allozymes, while the basis of immunological studies is antigen-antibody reactions. Basic methodologies for using DNA for systematic purposes include DNA-DNA hybridizations, restriction enzyme analysis, sequencing, cloning, PCR and PCR-based fingerprinting …
Investigation Of The Antimicrobial Activity Of Some Streptomyces Isolates, Nuretti̇n Şahi̇n, Aysel Uğur
Investigation Of The Antimicrobial Activity Of Some Streptomyces Isolates, Nuretti̇n Şahi̇n, Aysel Uğur
Turkish Journal of Biology
Seventy-four different Streptomyces isolates were obtained from the soils of Muğla province. Antimicrobial activity was determined in 45.9% of the isolates. Fifteen isolates showed strong activity against coagulase-negative Staphylococcus (CoNS). These isolates were extensively studied for their in vitro antimicrobial activity against Gram-positive and Gram-negative bacteria and yeasts. The results indicated that five isolates were highly active against CoNS and yeast with an inhibition zone at ? 20 mm. Three of these isolates were identified as Streptomyces antibioticus (MU106, MU107) and S. rimosus (MU114). The UV spectra of the culture extracts for the active isolates showed absorbance peaks ranging between …
Quorum Sensing In Gram-Negative Bacteria, Gülgün Boşgelmez Tinaz
Quorum Sensing In Gram-Negative Bacteria, Gülgün Boşgelmez Tinaz
Turkish Journal of Biology
It has become increasingly and widely recognised that bacteria do not live as isolated entities but instead exist as communities that exploit elaborate systems of intercellular communication to facilitate their adaptation to changing environmental conditions. A well-characterised example of such intercellular communication is quorum sensing. Quorum sensing depends on the production of diffusible signal molecules termed autoinducers or pheromones, which enable a bacterium to monitor its own cell population density. A variety of physiological processes in a range of bacterial species is regulated by quorum sensing. Examples include bioluminescence, antibiotic biosynthesis, swarming, biofilm differentiation, conjugation and the production of virulence …