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2003

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Articles 2131 - 2160 of 2567

Full-Text Articles in Life Sciences

Phylogenetic Analysis Of The Metastrongyloidea (Nematoda: Strongylida) Inferred From Ribosomal Rna Gene Sequences, Ramon A. Carreno, Steven A. Nadler Jan 2003

Phylogenetic Analysis Of The Metastrongyloidea (Nematoda: Strongylida) Inferred From Ribosomal Rna Gene Sequences, Ramon A. Carreno, Steven A. Nadler

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Phylogenetic relationships among nematodes of the strongylid superfamily Metastrongyloidea were analyzed using partial sequences from the large-subunit ribosomal RNA (LSU rRNA) and small-subunit ribosomal RNA (SSU rRNA) genes. Regions of nuclear ribosomal DNA (rDNA) were amplified by polymerase chain reaction, directly sequenced, aligned, and phylogenies inferred using maximum parsimony. Phylogenetic hypotheses inferred from the SSU rRNA gene supported the monophyly of representative taxa from each of the 7 currently accepted metastrongyloid families. Metastrongyloid taxa formed the sister group to representative trichostrongyloid sequences based on SSU data. Sequences from either the SSU or LSU RNA regions alone provided poor resolution for …

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Testis Size Increases With Colony Size In Cliff Swallows, Charles R. Brown, Mary Bomberger Brown Jan 2003

Testis Size Increases With Colony Size In Cliff Swallows, Charles R. Brown, Mary Bomberger Brown

School of Biological Sciences: Faculty Publications

By using a sample of more than 800 male cliff swallows (Petrochelidon pyrrhonota) that died during a rare climatic event in our Nebraska study area in 1996, we investigated how testis size was related to body size, age, parasite load, a bird’s past colony-size history, and spleen size. Testis volume in-creased with body size. After correcting for body size, testis volume was lowest for birds age 1 and 2 years but did not vary with age for males 3 years old or more. Birds occupying parasite-free (fumigated) colonies had significantly larger testes than did birds at non-fumigated sites. …

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The Safety Of Genetically Modified Foods Produced Through Biotechnology, Robert M. Hollingworth, Leonard F. Bjeldanes, Michael Bolger, Ian Kimber, Barbara Jean Meade, Steve L. Taylor, Kendall B. Wallace Jan 2003

The Safety Of Genetically Modified Foods Produced Through Biotechnology, Robert M. Hollingworth, Leonard F. Bjeldanes, Michael Bolger, Ian Kimber, Barbara Jean Meade, Steve L. Taylor, Kendall B. Wallace

Department of Food Science and Technology: Faculty Publications

The Society of Toxicology (SOT) is committed to protecting and enhancing human, animal, and environmental health through the sound application of the fundamental principles of the science of toxicology. It is with this goal in mind that the SOT defines here its current consensus position on the safety of foods produced through biotechnology (genetic engineering). These products are commonly termed genetically modified foods, but this is misleading, since conventional methods of microbial, crop, and animal improvement also produce genetic modifications and these are not addressed here.
The available scientific evidence indicates that the potential adverse health effects arising from biotechnology-derived …

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Genome Diversification In Phylogenetic Lineages I And Ii Of Listeria Monocytogenes: Identification Of Segments Unique To Lineage Ii Populations, Chaomei Zhang, Min Zhang, Jingliang Ju, Joseph Nietfeldt, John Wise, Phillip M. Terry, Michael Olson, Stephen D. Kachman, Martin Wiedmann, Mansour Samadpour, Andrew K. Benson Jan 2003

Genome Diversification In Phylogenetic Lineages I And Ii Of Listeria Monocytogenes: Identification Of Segments Unique To Lineage Ii Populations, Chaomei Zhang, Min Zhang, Jingliang Ju, Joseph Nietfeldt, John Wise, Phillip M. Terry, Michael Olson, Stephen D. Kachman, Martin Wiedmann, Mansour Samadpour, Andrew K. Benson

Department of Food Science and Technology: Faculty Publications

Thirteen different serotypes of Listeria monocytogenes can be distinguished on the basis of variation in somatic and flagellar antigens. Although the known virulence genes are present in all serotypes, greater than 90% of human cases of listeriosis are caused by serotypes 1/2a, 1/2b, and 4b and nearly all outbreaks of food-borne listeriosis have been caused by serotype 4b strains. Phylogenetic analysis of these three common clinical serotypes places them into two different lineages, with serotypes 1/2b and 4b belonging to lineage I and 1/2a belonging to lineage II. To begin examining evolution of the genome in these serotypes, DNA microarray …

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Wagonhammer Education Center Groundbreaking, John Owens Jan 2003

Wagonhammer Education Center Groundbreaking, John Owens

John Owens: Speeches and Appearances

Last year when I had the opportunity to speak at the 2002 Gudmundsen Sandhills Laboratory Open House I noted the tremendous gift Pete and Abbie Gudmundsen gave the university, the people who live throughout their beloved Sandhills, and, indeed, the entire state of Nebraska when they donated their almost 13,000 acre ranch, the Rafter C, to the University of Nebraska Foundation back in 1978.

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Coccidia In The Mammary Glands Of Shrews (Order: Insectivora), Donald W. Duszynski, William C. Marquardt Jan 2003

Coccidia In The Mammary Glands Of Shrews (Order: Insectivora), Donald W. Duszynski, William C. Marquardt

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Three of 6 female long-clawed shrews, Sorex unguiculatus Dobson, 1890, collected on the island of Hokkaido, Japan, were found to have unsporulated oocysts and sexual stages (both macro- and microgamonts) in varying stages of development of an unidentified coccidium in both lactating and non lactating mammary glands. Gamonts developed in the alveoli of the mammary glands, and oocysts were found in the lactiferous ducts and in pools of milk. Mature macrogamonts were 11.9 × 15.2 μm (10-14 × 14-20 μm), whereas completely developed microgamonts with many gametes were 14.8 × 16.8 μm (10-18 × 13-20 μm). Oocysts in tissue sections …

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Eimeria Species From Cryptotis Shrews (Insectivora: Soricidae) With Description Of A New Species, Donald W. Duszynski, Ralph P. Eckerlin, Timothy J. Mccarthy Jan 2003

Eimeria Species From Cryptotis Shrews (Insectivora: Soricidae) With Description Of A New Species, Donald W. Duszynski, Ralph P. Eckerlin, Timothy J. Mccarthy

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Fresh fecal samples from 12 shrews, 10 Cryptotis goodwini Jackson, 1933, and 2 Cryptotis merriami Thomas, 1898, were collected between December 1994 and May 1998; 11 (92%) were positive for eimeriid coccidia, including 8 of 8 C. goodwini and 2 of 2 C. merriami from Honduras and 1 of 2 C. goodwini from Guatemala. Two Eimeria species were found: 1 is consistent with the description of Eimeria whitakeri Upton and McAllister, 1991, and 1 is described in this study as new. Sporulated oocysts of the new species are subspheroidal, 16.8 × 15.7 (14–20 × 15–19) μm, with a length–width (L/W) …

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Experimental Mycobacteriosis In Striped Bass Morone Saxatilis, D. T. Gauthier, M. W. Rhodes, W. K. Vogelbein, H. Kator, C. A. Ottinger Jan 2003

Experimental Mycobacteriosis In Striped Bass Morone Saxatilis, D. T. Gauthier, M. W. Rhodes, W. K. Vogelbein, H. Kator, C. A. Ottinger

Biological Sciences Faculty Publications

Striped bass Morone saxatilis were infected intraperitoneally with approximately 105 Mycobacterium marinum, M. shottsii sp. nov., or M. gordonae. Infected fish were maintained in a flow-through freshwater system at 18 to 21°C, and were examined histologically and bacteriologically at 2, 4, 6, 8, 17, 26, 36 and 45 wk post-infection (p.i.). M. marinum caused acute peritonitis, followed by extensive granuloma development in the mesenteries, spleen and anterior kidney. Granulomas in these tissues underwent a temporal progression of distinct morphological stages, culminating in well-circumscribed lesions surrounded by normal or healing tissue. Mycobacteria were cultured in high numbers from …

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Enhancement Of Disease And Pathology By Synergy Of Trichuris Suis And Campylobacter Jejuni In The Colon Of Immunologically Naive Swine, Linda S. Mansfield, David T. Gauthier, Sheila R. Abner, Kathryn M. Jones, Stacey R. Wilder, Joseph F. Urban Jan 2003

Enhancement Of Disease And Pathology By Synergy Of Trichuris Suis And Campylobacter Jejuni In The Colon Of Immunologically Naive Swine, Linda S. Mansfield, David T. Gauthier, Sheila R. Abner, Kathryn M. Jones, Stacey R. Wilder, Joseph F. Urban

Biological Sciences Faculty Publications

Campylobacter jejuni, a leading cause of bacterial gastroenteritis, has different age distribution and disease expression in developing and developed countries, which may be due to the endemnicity of infection and the age of acquisition of immunity. Differences in disease expression are not solely dependent on the C jejuni strain or virulence attributes. Another modulating factor in developing countries may be endemic nematode infections such as Trichuris, which drive type 2 cytokine responses and down-regulate type I immune responses. In this study, three-day-old germfree pigs given dual infections with Trichuris suis and C jejuni had more frequent, more severe …

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Chemical Composition Of Some Components Of The Arrestment Pheromone Of The Black-Legged Tick, Ixodes Scapularis (Acari : Ixodidae) And Their Use In Tick Control, Daniel E. Sonenshine, Trevor Adams, Sandra A. Allan, John Mclaughlin, Francis X. Webster Jan 2003

Chemical Composition Of Some Components Of The Arrestment Pheromone Of The Black-Legged Tick, Ixodes Scapularis (Acari : Ixodidae) And Their Use In Tick Control, Daniel E. Sonenshine, Trevor Adams, Sandra A. Allan, John Mclaughlin, Francis X. Webster

Biological Sciences Faculty Publications

Chemical analysis (high-performance liquid chromatography) and bioassay demonstrated the presence of compounds that seem to be components of the Ixodes scapularis arrestment pheromone. Only two purines, guanine and xanthine, were found in acidified saline extracts made from cast skins after molting of fed nymphs, fed larvae, and fecal/excretory exudates deposited by unfed adults on substrates in their environment. The ratio of guanine to xanthine was 10.6:1 in an extract from the nymphal skins versus 0.95:1 in an extract from the larval skins. Guanine, xanthine, and traces of a third purine, tentatively identified as 8-azaguanine, were found in extracts made from …

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Dna Sequence Of Melanocortin 1-Receptor Gene In Coturnix Japonica: Correlation With Three E Locus Alleles—E,E+, And Erh, Rupali Ugrankar, Kim Cheng, Ronald Okimoto Jan 2003

Dna Sequence Of Melanocortin 1-Receptor Gene In Coturnix Japonica: Correlation With Three E Locus Alleles—E,E+, And Erh, Rupali Ugrankar, Kim Cheng, Ronald Okimoto

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

The melanocortin 1-receptor (MC1-R) gene plays a key role in the expression of fur and feather color in mammals and birds by regulating the distribution of two melanin pigments: eumelanin (black/brown) and pheomelanin (red/yellow). MC1-R corresponds to the classical Extension (E) locus in mice, pigs, dogs, horses, and chickens. Three E locus alleles, the wild-type (e+), brown (E), and redhead (erh) have been identified in Japanese quail (Coturnix japonica). To determine if the quail E locus phenotypes were due to variation in the MC1-R gene, the coding region of the MC1-R gene was PCR amplified and DNA sequenced using genomic …

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Electrofusion Of Saccharomyces Cerevisiae Auxotrophic Mutants Of Identical Mating Type Using A Laboratory-Made System, Gökhan Coral, Ömer Çolak, M. Ni̇sa Ünaldi, Burhan Arikan Jan 2003

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 …

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Extremely Halophilic Bacterial Communities In Şereflikoçhisar Salt Lake In Turkey, Meral Bi̇rbi̇r, Cenk Sesal Jan 2003

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 …

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Biosorption Of Copper Ions By Caustic Treated Waste Baker's Yeast Biomass, Yekta Göksungur, Si̇bel Üren, Ulgar Güvenç Jan 2003

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 …

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Acid Adaptation Protects Salmonella Typhimurium From Environmental Stresses, Hali̇l Tosun, Şahi̇ka Aktuğ Gönül Jan 2003

Acid Adaptation Protects Salmonella Typhimurium From Environmental Stresses, Hali̇l Tosun, Şahi̇ka Aktuğ Gönül

Turkish Journal of Biology

Salmonella typhimurium can encounter a wide variety of environments during its life cycle. S. typhimurium can experience and survive dramatic acid stress. However, in vitro the organism is very sensitive to acid. S. typhimurium was adapted to acid by exposure to HCl at pH 5.8 ± 0.1 for one growth cycle. Acid-adapted cells were much better protected from acid death than control cells. The relationship between acid adaptation of S. typhimurium and tolerance to other environmental stresses was also examined. Acid-adapted cells were found to have increased tolerance to various stresses including heat, salt and organic acids. No cross-protection was …

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Determination Of Poly-\Beta-Hydroxybutyrate (Phb) Production By Some Mesophilic And Thermophilic Lactic Acid Bacteria, Zehra Nur Yüksekdağ, Yavuz Beyatli, Belma Aslim Jan 2003

Determination Of Poly-\Beta-Hydroxybutyrate (Phb) Production By Some Mesophilic And Thermophilic Lactic Acid Bacteria, Zehra Nur Yüksekdağ, Yavuz Beyatli, Belma Aslim

Turkish Journal of Biology

Accumulated poly-\beta-hydroxybutyrate (PHB) was determined in lactic acid bacteria belonging to the genera Lactobacillus, Lactococcus and Streptococcus. Lactobacilli were grown in MRS broth and the others were grown in Elliker broth medium. Cell biomass was obtained by centrifugation. The cell walls were lysed with sodium hypochlorite. Poly-\beta-hydroxybutyrate was extracted using chloroform in a Soxhlet system. Then it was converted to crotonic acid using sulfuric acid and the amount of crotonic acid was measured spectrophotometrically. The yield of poly-\beta-hydroxybutyrate % of cell dry weight of Lactobacillus species was 0.52-25.55%. The values for Lactococcus and Streptococcus species were 0.61-14.81 and 1.20-13.69%, respectively. …

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Cytogenetic Effects Of Copper Chloride On The Root Tip Cells Of Helianthus Annuus L., Hüseyi̇n İnceer, Sema Ayaz, Osman Beyazoğlu, Emi̇ne Şentürk Jan 2003

Cytogenetic Effects Of Copper Chloride On The Root Tip Cells Of Helianthus Annuus L., Hüseyi̇n İnceer, Sema Ayaz, Osman Beyazoğlu, Emi̇ne Şentürk

Turkish Journal of Biology

The cytogenetic effects of copper chloride on root tip cells of Helianthus annuus were investigated. Seeds were treated with 10, 25, 50 and 100 mg/L (ppm) of copper chloride for 24 h. It was found that copper chloride has a marked mitodepressive action on mitosis. Mitotic abnormalities were increased and the mitotic index was decreased depending on the concentration of the copper chloride applied.

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Protein And Dna In Systematic Biology, Selma Gülbi̇tti̇ Onarici, Si̇bel Sümer Jan 2003

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 …

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Reproductive Response Of Adult Siberian Hamsters To One-Hour Melatonin Infusions, Bülent Gündüz, Milton H. Stetson Jan 2003

Reproductive Response Of Adult Siberian Hamsters To One-Hour Melatonin Infusions, Bülent Gündüz, Milton H. Stetson

Turkish Journal of Biology

The pineal hormone melatonin is known to play an important role in mediating photoperiodic messages to the reproductive system in seasonal breeding animals. In this study, we investigated whether a 1 h subcutaneous infusion of 50 ng of melatonin at 2000-2100 hours, effective in causing inhibition of testicular development in the juvenile Siberian hamsters (Phodopus sungorus), would cause testicular regression in adults of this species housed on a long photoperiod (LD16:8). Pinealectomized adult hamsters received programmed subcutaneous infusions of 50 or 500 ng of melatonin or vehicle (0.12 ml) at 2000-2100 hours each day for 8 weeks. We found that …

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Neuroepithelial Endocrine Cells In The Lung Of Rana Ridibunda: An Immunohistochemical Study, Füsun Öztay, Ayşe Tabakoğlu Oğuz Jan 2003

Neuroepithelial Endocrine Cells In The Lung Of Rana Ridibunda: An Immunohistochemical Study, Füsun Öztay, Ayşe Tabakoğlu Oğuz

Turkish Journal of Biology

In this study, neuroepithelial endocrine cells were for the first time identified in the lung of Rana ridibunda. The presence of these cells was investigated using endocrine markers by the immunohistochemical method at the light microscopic level. Immunoreactive - cells containing serotonin, calcitonin, met-enkephalin and leu-enkephalin were observed alone or in clusters within the respiratory epithelium. In general, clustered - cells containing serotonin were detected among the ciliated cells and goblet cells of the pseudostratified epithelium on apical dilation of the primary septa where the inhaled - air is first met. Among pneumocytes, single and clustered neuroepithelial endocrine cells display …

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Phospholipid And Triacylglycerol Fatty Acid Compositions From Various Development Stages Of Melanogryllus Desertus Pall. (Orthoptera: Gryllidae), Kadri̇ Bozkuş Jan 2003

Phospholipid And Triacylglycerol Fatty Acid Compositions From Various Development Stages Of Melanogryllus Desertus Pall. (Orthoptera: Gryllidae), Kadri̇ Bozkuş

Turkish Journal of Biology

Phospholipid and triacylglycerol fatty acid compositions from eggs; seventh, eighth and last nymphal stages; and 1, 20- and 40-day-old adult females of the black cricket, Melanogryllus desertus, grown in stock-culture medium under laboratory conditions were analyzed by gas chromatographic methods. A large amount of the fatty acid components at all the development stages of the insects analyzed comprised oleic, linoleic, palmitic and stearic acids. However, palmitoleic, myristic and linolenic acids were also found, at lower levels. There were fluctuations in fatty acid levels at different development stages, such as nymphs and adults. Oleic acid was lower in 1-day-old and older …

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Investigation Of The Antimicrobial Activity Of Some Streptomyces Isolates, Nuretti̇n Şahi̇n, Aysel Uğur Jan 2003

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 …

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Quorum Sensing In Gram-Negative Bacteria, Gülgün Boşgelmez Tinaz Jan 2003

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 …

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Adventitious Shoot Organogenesis And Plant Regeneration From Cotyledons Of Diploid Diyarbakır Watermelon (Citrullus Lanatus Cv. "Sürme"), Vedat Pi̇ri̇nç, Ahmet Onay, Fi̇li̇z Adiyaman, Çi̇ğdem Işikalan, Engi̇n Ti̇lkat, Davut Başaran Jan 2003

Adventitious Shoot Organogenesis And Plant Regeneration From Cotyledons Of Diploid Diyarbakır Watermelon (Citrullus Lanatus Cv. "Sürme"), Vedat Pi̇ri̇nç, Ahmet Onay, Fi̇li̇z Adiyaman, Çi̇ğdem Işikalan, Engi̇n Ti̇lkat, Davut Başaran

Turkish Journal of Biology

Adventitious shoots were obtained from the diploid Diyarbakır watermelon cultivar "Sürme" by culturing cotyledons on shoot regeneration medium for 3 weeks. The effects of two cytokinins, benzyl amino purine (BA) and kinetine (Kin), on shoot organogenesis were examined. The number of shoots per explant were approximately more than 50% higher when 0.5 mg/l BA was used compared to the most effective kinetin concentration (1 mg/l). Plants were obtained by transferring 1 to 2 cm shoots to MS medium supplemented with 1-4 mg/l naphthalene acetic acid. Most of the regenerated plants (more than 50%) were successfully transplanted to the field. This …

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Epipelic And Epilithic Algae Of Lower Parts Of Yanbolu River (Trabzon, Turkey), Bülent Şahi̇n Jan 2003

Epipelic And Epilithic Algae Of Lower Parts Of Yanbolu River (Trabzon, Turkey), Bülent Şahi̇n

Turkish Journal of Biology

The algae of Yanbolu River were investigated in samples collected from different habitats (epipelic, epilithic) at two stations between October 2000 and September 2001. The flora consisted of 78 taxa belonging to the Bacillariophyta (47 taxa), Cyanophyta (16 taxa), Chlorophyta (14 taxa) and Euglenophyta (1 taxon). The Bacillariophyta was the dominant form of algal flora. Amphora ovalis var. pediculus, Ceratoneis arcus, Cymbella affinis, C. minuta, Didymosphenia geminata, Melosira varians and Synedra ulna were the most frequent taxa in the algal flora. While the maximum density of the epipelic community was 29,555 cells/cm*2 at station I in June, it was 27,756 …

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Investigation Of The Microfungal Flora Of The Bird Paradise National Park In Bandırma, Balıkesir (Turkey), Ayşe Di̇lek Azaz Jan 2003

Investigation Of The Microfungal Flora Of The Bird Paradise National Park In Bandırma, Balıkesir (Turkey), Ayşe Di̇lek Azaz

Turkish Journal of Biology

Fifteen soil samples taken from the Bird Paradise National Park in Bandırma were investigated using the soil dilution plate and soil washing methods. Thirty-three species and four different sterile microfungal taxa were identified. Twenty-eight of these species belonged to the Hyphomycetes and 5 to the Mucorales. The genus with the highest species diversity found in the study area was Penicillium, represented by 16 species. Some chemical properties of the soil samples were also established. Quantitative analysis based on the soil dilution plate method revealed a statistically significant difference between soil samples subjected to the rising water level of the lake …

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Characterization Of Salivaricin B, A Protein Expressed By Lactobacillus Salivarius M7, Osman Çataloluk, Candan G. Gürakan Jan 2003

Characterization Of Salivaricin B, A Protein Expressed By Lactobacillus Salivarius M7, Osman Çataloluk, Candan G. Gürakan

Turkish Journal of Biology

Salivaricin B (SalB) is a protein encoded by Lactobacillus salivarius M7. This protein is insensitive to proteolytic enzymes, such as pepsin, trypsin, and chymotrypsin, but is partially sensitive to proteinase K. SalB is also stable and maintains its activity over a range of pHs, from 3 to 9. SalB was found to be effective against many closely related lactic acid bacteria such as, L. fermentum, L. plantarum, L. acidophilus and distantly related gram-positive bacteria, including Listeria monocytogenes, Streptococcus faecalis, Staphylococcus aureus and Staph. epidermidis. The mode of action of SalB was obviously bactericidal, and death occurs without bacterial lysis. The …

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Modification By Compositional Antimutagens Of The Key Stages Of A Mutation Process, Urkhan Alekperov, Ali Aliev, Afet Rustamova, Saida Jafarova Jan 2003

Modification By Compositional Antimutagens Of The Key Stages Of A Mutation Process, Urkhan Alekperov, Ali Aliev, Afet Rustamova, Saida Jafarova

Turkish Journal of Biology

In experiments with Escherichia coli B/r WP2(trpE-), mice marrow cells and human lymphocytes the antimutagenic activity of an extract from Zizyphus mill was performed. The extract was tested separately and in mixture with Triticum aestivum. In experiments with different treatment schemes it has been established that the extract from wheat sprouts added to an antimutagenic preparation from Zizyphus mill intensifies the genoprotective properties of the Zizyphus mill extract.

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The Effects Of Dietary Fatty Acids On The Fatty Acid Composition In The Phospholipid Fraction Of Gambusia Affinis, Eli̇f İpek Cengi̇z, Erhan Ünlü, Mehmet Başhan Jan 2003

The Effects Of Dietary Fatty Acids On The Fatty Acid Composition In The Phospholipid Fraction Of Gambusia Affinis, Eli̇f İpek Cengi̇z, Erhan Ünlü, Mehmet Başhan

Turkish Journal of Biology

The present study represents an investigation into the effect of dietary fatty acids on the fatty acid composition of the phospholipid fraction of Gambusia affinis, a small freshwater fish living in a source located on the campus of Dicle University. The fatty acid composition of the phospholipid fraction was analysed by gas chromatography for fish collected from the freshwater source, which were naturally fed, and also fish fed an artificial diet with a w6/w3 ratio of 5.5:1 for 30 days. The level of w3 in the fish fed artificially for 30 days was higher than in those collected from the …

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Evaluation Of The Reproductive Potential And Competition Between Two Entomopathogenic Nematodes, Steinernema Feltiae Filipjev, 1934 (Rhabditida: Steinernematidae) And Heterorhabditis Bacteriophora, Poinar 1976 (Rhabditida: Heterorhabditidae), Işik Oğuzoğlu Ünlü, Nurdan Özer Jan 2003

Evaluation Of The Reproductive Potential And Competition Between Two Entomopathogenic Nematodes, Steinernema Feltiae Filipjev, 1934 (Rhabditida: Steinernematidae) And Heterorhabditis Bacteriophora, Poinar 1976 (Rhabditida: Heterorhabditidae), Işik Oğuzoğlu Ünlü, Nurdan Özer

Turkish Journal of Biology

The emergence in Galleria mellonella (L.) larva, which was infected by Steinernema feltiae and Heterorhabditis bacteriophora, began on the ninth day after exposure to the former nematode and the sixth day of exposure to the latter nematode (25 ± 0.5 ºC). The average number of nematodes developing in each host was as 13,829, and the range was from 4365 to 27,510 for S. feltiae infection. The average number of nematodes per host was 141,562, and the range was 50,905 - 271,593 for H. bacteriophora infection. When the 2 different species were inoculated simultaneously into the same host, H. bacteriophora caused …

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