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Full-Text Articles in Life Sciences

The Return Of The Wild, John Jahoda Dec 1999

The Return Of The Wild, John Jahoda

Bridgewater Review

No abstract provided.


Three-Dimensional Reconstructions Of Tadpole Chondrocrania From Historical Sections, Gary Radice, Mary K. Boggiano, Mark Desantis, Peter Larson, Joseph Oppong, Matthew Smetanick, Todd Stevens, James Tripp, Rebecca Weber, Michael Kerckhove, Rafael De Sá Oct 1999

Three-Dimensional Reconstructions Of Tadpole Chondrocrania From Historical Sections, Gary Radice, Mary K. Boggiano, Mark Desantis, Peter Larson, Joseph Oppong, Matthew Smetanick, Todd Stevens, James Tripp, Rebecca Weber, Michael Kerckhove, Rafael De Sá

Virginia Journal of Science

Reconstructing three dimensional structures (3DR) from histological sections has always been difficult but is becoming more accessible with the assistance of digital imaging. We sought to assemble a low cost system using readily available hardware and software to generate 3DR for a study of tadpole chondrocrania. We found that a combination of RGB can1era, stereomicro­scope, and Apple Macintosh PowerPC computers running NIH Image, Object Image, Rotater, and SURFdriver software provided acceptable reconstruc­tions. These are limited in quality primarily by the distortions arising from histological protocols rather than hardware or software.


Cartilage Regeneration On A Large Articular Surface Facilitated By Stress Shielding, Charles L. Mcdowell, Jennifer S. Wayne, Robert Tuten, Hunter H. Mcguire Jr. Oct 1999

Cartilage Regeneration On A Large Articular Surface Facilitated By Stress Shielding, Charles L. Mcdowell, Jennifer S. Wayne, Robert Tuten, Hunter H. Mcguire Jr.

Virginia Journal of Science

An animal model for the study of articular cartilage regeneration in-vivo facilitated by stress-shielding is introduced. The object of the model is to test the hypothesis that some form of cartilaginous tissue will grow upon a large joint surface in vivo with the joint in normal motion. The model utilizes the known capability of immature cells to differentiate. The source of cells is bleeding subchondral bone. In addition, the model provides a mechanically shielded environment in which cell differentiation and maturation can occur. The study showed that a substantial amount of tissue will grow in the animal model only when …


Conservation Status Of The Southern Appalachian Herpetofauna, Joseph C. Mitchell, Thomas K. Pauley, David I. Withers, Steven M. Roble, Brian T. Miller, Alvin L. Braswell, Paul V. Cupp Jr., Christopher S. Hobson Apr 1999

Conservation Status Of The Southern Appalachian Herpetofauna, Joseph C. Mitchell, Thomas K. Pauley, David I. Withers, Steven M. Roble, Brian T. Miller, Alvin L. Braswell, Paul V. Cupp Jr., Christopher S. Hobson

Virginia Journal of Science

Seventy one species of amphibians (55 salamanders, 16 anurans) and 46 species of reptiles (15 turtles, 8 lizards, 23 snakes) inhabit a five state area (Kentucky, North Carolina, Tennessee, Virginia, West Virginia) in the southern Appalachian region bordered by the Potomac River, the Blue Ridge Mountains, and the western margin of the Appalachian Plateau. Of these, 47.9 % of the amphibian fauna and 52.2 % of the reptilian fauna are listed as being of conservation concern by federal, state, and Natural Heritage programs in all or a portion of their ranges of this region. The Shenandoah salamander (Plethodon Shenandoah …


Characterization And Identification Of A Sludge-Associated Bacterial Isolate, Abiodun O. Adibi, Derrell Mcpherson, Minna Laine Apr 1999

Characterization And Identification Of A Sludge-Associated Bacterial Isolate, Abiodun O. Adibi, Derrell Mcpherson, Minna Laine

Virginia Journal of Science

During a metal speciation study, an unusually high retention of lead ·was observed when lead solution was percolated through a column packed with sludge compost obtained from Hampton Roads Sanitation department. A bacterium was isolated from the sludge compost and identified as Bacillus sphaericus using electron microscopy, whole cell fatty acid analysis (Midi System) and Biolog GP Microplate. The isolate grows in broth and agar media containing up to 800 µM lead. Lead accumulation study using atomic absorption spectrophotometer indicates that the isolate adsorbs lead. Lead adsorption is pH dependent. The isolate contains a plasmid of approximately 40 -50 kbp …


Historical Relationships Of Atlantic Slope River Drainages, Eugene G. Maurakis, Diana L. Lipscomb Apr 1999

Historical Relationships Of Atlantic Slope River Drainages, Eugene G. Maurakis, Diana L. Lipscomb

Virginia Journal of Science

An analysis of the historical relationships of 19 river drainages (St. Lawrence to Altamaha) on the Atlantic slope of the Appalachian Mountains was conducted using the shared presence of 124 native species of cyprinid fishes. This analysis resulted in an area cladogram that suggests that the rivers of the southern Atlantic slope were historically connected to the drainage of three southern rivers (Flint, Chattahoochee, and Apalachicola) which drain into the Gulf of Mexico. The mid Atlantic and northern Atlantic slope rivers appear to be historically related in support of earlier hypotheses that the mid Atlantic region provided a refugium for …


Possible Predation Scars On Rectithyris Subdepressa (Stoliczka, 1872), Late Cretaceous (Maastrichtian) Kallankurichi Fm., India, Rex Alan Hanger, Rama Krishnaswamy Apr 1999

Possible Predation Scars On Rectithyris Subdepressa (Stoliczka, 1872), Late Cretaceous (Maastrichtian) Kallankurichi Fm., India, Rex Alan Hanger, Rama Krishnaswamy

Virginia Journal of Science

A single specimen of the terebratulid brachiopod, Rectithyris subdepressa (Stoliczka, 1872) from the Late Cretaceous (Maastrichtian) Kallankurichi Fonnation of southern India was found with durophagous predation traces. This occurrence is significant as it is possibly the first documentation of elasmobranch shark predation on brachiopods from the Mesozoic.


Pcr And Fish Detection Extends The Range Of Pfiesteria Piscicida In Estuarine Waters, P. A. Rublee, J. Kempton, E. Schaefer, J.M. Burkholder, H. B. Glasgow Jr., David Oldach Jan 1999

Pcr And Fish Detection Extends The Range Of Pfiesteria Piscicida In Estuarine Waters, P. A. Rublee, J. Kempton, E. Schaefer, J.M. Burkholder, H. B. Glasgow Jr., David Oldach

Virginia Journal of Science

PCR and fluorescent in situ hybridization probes were used to assay for the presence of the dinoflagellate Pfiesteria piscicida in 170 estuarine water samples collected from New York to northern Florida. 20% of samples tested positive for the presence of P. piscicida, including sites where fish kills due to Pfiesteria have occurred and sites where there was no historical evidence of such events. The results extend the known range of P. piscicida northward to Long Island, New York. The results also suggest that P. piscicida is common, and normally benign, inhabitatant of estuarine waters of the eastern US.


A Cohort Study To Determine The Epidemiology Of Estuary-Associated Syndrome, Elizabeth Turf, Lily Ingsrisawang, Megan Turf, J.D. Ball, Michael Stutts, John Taylor, Suzanne Jenkins Jan 1999

A Cohort Study To Determine The Epidemiology Of Estuary-Associated Syndrome, Elizabeth Turf, Lily Ingsrisawang, Megan Turf, J.D. Ball, Michael Stutts, John Taylor, Suzanne Jenkins

Virginia Journal of Science

From the Introduction:

Estuary-Associated Syndrome (EAS) is the name given to a potential illness characterized primarily by changes in an individual's cognitive abilities, including acute onset of memory loss or the sudden inability to solve simple problems. Other possible signs of illness include respiratory symptoms, skin rash, or gastrointestinal distress. This illness appears to arise following exposure to toxin produced by Pfiesteria piscicida, or other toxic dinoflagellates, that resides in estuary waters.

….

In order to learn more about this possible syndrome and to determine if a causal relationship exists between association to waters containing Pfiesteria or other toxic …


Monitoring Results For Pfiesteria Piscidida And Pfiesteria-Like Organisms From Virginia Waters In 1998, Harold G. Marshall, David W. Seaborn, Jennifer Wolny Jan 1999

Monitoring Results For Pfiesteria Piscidida And Pfiesteria-Like Organisms From Virginia Waters In 1998, Harold G. Marshall, David W. Seaborn, Jennifer Wolny

Virginia Journal of Science

Results of an extensive 1998 monitoring program for the presence of Pfiesteria-like organisms (PLO) in Virginia estuaries indicate these dinoflagellates are widely distributed in both the water column, and as cysts in the sediment, however Pfiesteria piscicida was not detected at this time. The highest concentrations of PLO were in estuaries along the Virginia shore line of the Potomac River, and in western Chesapeake Bay estuaries from the Little Wicomico River to the Rappahannock River. The most common PLO included Cryptoperidiniopsis sp. and Gymnodinium galatheanum. The lowest PLO concentrations were at ocean side locations. PLO were also …


Production Of Monoclonal Antibodies Specific Forprogesterone, Fatma Şahi̇ngöz Yücel, Beyazit Çirakoğlu Jan 1999

Production Of Monoclonal Antibodies Specific Forprogesterone, Fatma Şahi̇ngöz Yücel, Beyazit Çirakoğlu

Turkish Journal of Biology

Progesterone levels in milk and serum are indicators of pregnancy in cattle. The progesterone level reaches a peak on the 21 st and 22 nd days of pregnancy. Monoclonal antibodies specific to progesterone could be used for the immunodetection of milk and serum progesterone levels. We report here the development of hybrid cells prdoducing monoclonal antibodies specific for progesterone using hybridoma technology. Hybridoma cells secreting monoclonal antibodies against progesterone (MAM 2H11, MAM 6G6) were developed by fusion of the spleen cells of an immunized BALB/c mouse with FO (ATCC CRL 1646) mouse myeloma cells. These monoclonal antibodies were characterized for …


Ultrastructural Observations On Connectioncomplexes Between The Mural Trophoblast Cells Ofblastocyst In The Rat, Ramazan Demi̇r, İsmai̇l Üstünel, Necdet Demi̇r Jan 1999

Ultrastructural Observations On Connectioncomplexes Between The Mural Trophoblast Cells Ofblastocyst In The Rat, Ramazan Demi̇r, İsmai̇l Üstünel, Necdet Demi̇r

Turkish Journal of Biology

It is generally accepted that implantation morphologically consists of the establishment of a contact between the blastocyst and the uterine tissues. During this contact and interaction process, many physiological, biochemical and ultrastructural factors are involved. The aim of this study was to describe the ultrastructure of connection complexes between mural trophoblast cells in the blastocystic ring in the rat. Implantation sites obtained from rats on day 5 of pregnancy were studied ultrastructurally. Connected complexes were observed between mural trophoblast cells in different three types: a) dense long line connection; b) desmosome-like sturctures; c) regular suture-like interdigitation resembling parallel railings. According …


The Accumulation And Histological Effects Of Theorganometallic Fungicide Propineb On The Organsof Fetuses And Female Rats During Pregnancy, Kemal Güven, Engi̇n Deveci̇, Davi̇d De Pomerai Jan 1999

The Accumulation And Histological Effects Of Theorganometallic Fungicide Propineb On The Organsof Fetuses And Female Rats During Pregnancy, Kemal Güven, Engi̇n Deveci̇, Davi̇d De Pomerai

Turkish Journal of Biology

Dithiocarbamate propineb is an organometal fungicide, which is widely used for the control of diseases in plants. Female Wistar rats were exposed orally to propineb concentrations of 200 and 400 ppm, from the 6th day of gestation up to birth. At 400 ppm, propineb showed a variety of macroscopic (e.g. ptosis and paralysis) and microscopic symptoms in the organs of both fetuses and female rats. We found that the body weights of both one-day old litters and their propineb-treated mothers were lower than those of the controls. Histological examination of the livers and kidneys of the fetuses and propineb-treated pregnant …


Lack Of Minority Advantage In Drosophilamelanogaster Mutants, Şükran Çakir, Aykut Kence Jan 1999

Lack Of Minority Advantage In Drosophilamelanogaster Mutants, Şükran Çakir, Aykut Kence

Turkish Journal of Biology

The objective of this study was to test the generality of frequency-dependent fitness in the mating behavior of Drosophila, called the minority effect and to investigate the effect of artificial olfactory cues and marking the flies by wing cillipng on the frequency-dependent mate choice. In the mating experiments using wild type (oregon) and mutant (white-eyed, sepia, ebony) strains of Drosophila melanogaster, the mating success of mutant males did not increase as their frequency decreased. In addition, the olfactory cue hypothesis was not supported by the results of the experiments with artificial scent. The results of this study did not support …


Purification And Characterization Of Cysteine-43mutant Citrate Synthase From Thermoplasmaacidophilum, İpek Erduran, Semra Kocabiyik Jan 1999

Purification And Characterization Of Cysteine-43mutant Citrate Synthase From Thermoplasmaacidophilum, İpek Erduran, Semra Kocabiyik

Turkish Journal of Biology

Two cysteine residues were introduced to selected positions (Serine-309 and Serine-43) of the Thermoplasma acidophilum citrate synthase. Serine-309 Cysteine mutation drastically reduced the activity, as well as the thermostabiity of the enzyme. Although Serine-43 Cysteine mutation reduced the enzyme activity, it did not have any effect on the thermostability. Both wild-type and cysteine-43 mutant Thermoplasma citrate synthase enzymes were purified to homogenity using affinity chromatography on Matrex Gel Red A. The cysteine-43 mutant Thermoplasma citrate synthase was strikingy similar to the wild-type recombinant citrate synthase in its molecular size, substrate and co-factor specificities, pH profile and thermal resistance. The decrease …


Determination Of The Presence Of Crpgenes Instaphylococcus Aureus, Staphylococcus Epidermidis,Lactobacillus Delbrueckii Andcorynebacterium Verasuş, Ali̇ Osman Beldüz, Zi̇hni̇ Demi̇rbağ, Sabri̇ye Dülger, Ali̇ Osman Kiliç Jan 1999

Determination Of The Presence Of Crpgenes Instaphylococcus Aureus, Staphylococcus Epidermidis,Lactobacillus Delbrueckii Andcorynebacterium Verasuş, Ali̇ Osman Beldüz, Zi̇hni̇ Demi̇rbağ, Sabri̇ye Dülger, Ali̇ Osman Kiliç

Turkish Journal of Biology

Polymerase chain reaction (PCR) was employed to detect the presence of cyclic AMP receptor protein (CPR) in a number of diverse organisms. In PCR, two primers specific to the crp gene of Escherichia coli were used. Staphylococcus aureus, Staphylococcus epidermidis, Lactobacillus delbrueckii and Corynebacterium veraSuş all showed the same size of PCR frağments (708 bp) and same restriction frağment length polymorphizm (RFLP).


Properties Of The Rhodopseudomonas Palustrisstrains Isolated From An Alkaline Lake In Turkey, Gönül Çeti̇nkaya Dönmez, Ayten Öztürk, Lütfü Çakmakçi Jan 1999

Properties Of The Rhodopseudomonas Palustrisstrains Isolated From An Alkaline Lake In Turkey, Gönül Çeti̇nkaya Dönmez, Ayten Öztürk, Lütfü Çakmakçi

Turkish Journal of Biology

31 photoheterotrophic bacteria were isolated from Lake Aksehir sediment. Identification of the strains was based on morphological properties, motility and pigment composition, and also physiological properties such as carbon utilization and ability to respire anaerobically and aerobically in the dark. All strains were identified as Rhodopseudomonas palustris, but some strains were distinct from R. palustris with regard to vitamin requirement, malate utilization and aerobic growth in the dark. Until now, R. palustris had not been reported from an alkaline lake, and the strains growing alkaline pH (9) could be new strains of R. palustris.


Isolation And Abundance Of Unicellularcyanobacteria From Mosquito Development Sites, Gönül Çeti̇nkaya Dönmez, Ayşe Elmaci, Olcay Obali, Ayten Öztürk, Lütfü Çakmakçi Jan 1999

Isolation And Abundance Of Unicellularcyanobacteria From Mosquito Development Sites, Gönül Çeti̇nkaya Dönmez, Ayşe Elmaci, Olcay Obali, Ayten Öztürk, Lütfü Çakmakçi

Turkish Journal of Biology

The genus composition of cyanobacteria (particularly Chroococcus sp.) and their abundance in mosquito breeding sites at Lake Mogan (Ankara, Turkey) increased from August to September. Six unicellular cyanobacteria that had different morphological properties were isolated and succesfully cultivated. According to the mode of division, these six strain were classified as the represantatives of subgroup 1 (order Choroococcales). One of the isolates was identified as Synechococcus sp. and one as Gloeocapsa sp., and four were identified as Synechocystic sp. One of the four Synechocystis spp. was shown to be capable of heterotrophic growth.


Determination Of Salt Tolerance In Some Grapevinecultivars ( Vitis Vinifera L.) Under In Vitro Conditions, Nuray Si̇vri̇tepe, Ati̇lla Eri̇ş Jan 1999

Determination Of Salt Tolerance In Some Grapevinecultivars ( Vitis Vinifera L.) Under In Vitro Conditions, Nuray Si̇vri̇tepe, Ati̇lla Eri̇ş

Turkish Journal of Biology

Salinity tests were conducted on Çavus, Müsküle and Sultani Çekirdeksiz grapevine cultivars under in vitro conditions. Plant materials used in the salinity test were propagated using the axillary bud culture method. Single-node shoots were subjected to five different NaCl concentrations (0.00,0.25, 0.50, 0.75 and 1.00%) in MS+5 M BA medium for two periods (4 and 8 weeks). Proliferation, growth, total chlorophyll content and viability of explants decreased due to the increase in NaCl concentration and length of treatment period. Moreover, it was determined that salt treatment caused necroses in explants and the severity of this injury varied depending on the …


Toxicity Of Zinc, Copper And Lead To Idotea Baltica(Crustacea, Isopoda), Levent Bat, Murat Sezgi̇n, Ayşe Gündoğdu, Mehmet Çulha Jan 1999

Toxicity Of Zinc, Copper And Lead To Idotea Baltica(Crustacea, Isopoda), Levent Bat, Murat Sezgi̇n, Ayşe Gündoğdu, Mehmet Çulha

Turkish Journal of Biology

The acute toxicity of zinc, copper and lead to the marine invertebrate Idotea baltica (Crustacea, Isopoda) was evaluated by static bioassays, calculating the LT 50 (lethality time for 50%) for males and females. Survival time decreased with increasing concentrations of zinc, copper and lead. Zinc was more toxic to Idotea than copper and lead. Lead was the least toxic of the metals tested.


Analysis Of Some Leguminous Plants For Pyrimidineconstituents, Yusuf Turan Jan 1999

Analysis Of Some Leguminous Plants For Pyrimidineconstituents, Yusuf Turan

Turkish Journal of Biology

The pyrimidine and pyrimidine-derived secondary compounds of Phaseolus aureus and Glycine max were investigated. Batches, each consisting of one hundred 12-day-old seedlings of either P. aureus or of G. max were separately extracted in cold dilute (0.6 M) perchloric acid. After preliminary purification of extracts by charcoal adsorption and elution, and by PVP treatment, the extracts were subjected to paper chromatography and high voltage paper electrophoresis. The UV-absorbing bands were detected by viewing chromatograms and electrophoretograms under UV-light and, where possible, identified. The results presented in this work show that these experimental plants do not synthesize and accumulate any significant …


Salinity Resistance Of Certain Rice ( Oryza Sativa L.)Cultivars, Mehmet Alpaslan, Aydin Güneş, Süleyman Taban Jan 1999

Salinity Resistance Of Certain Rice ( Oryza Sativa L.)Cultivars, Mehmet Alpaslan, Aydin Güneş, Süleyman Taban

Turkish Journal of Biology

A greenhouse experiment was carried out to evaluate the response of six rice ( Oryza sativa L.) cultivars (Ribe, Tri-445, Serhat 92, Kros 424, Baldo and Rocca) to NaCI salinity. While salinity inhibited the growth of all six cultivars, Baldo, Ribe, Rocca and Kros-424 were less affected than the other cultivars. Salt treatment increased Na and CI content of the plants, while it decreased K content. In general, the proline content and stomatal resistance of the cultivars were increased by salt treatment.


Biodegradation Of Homocyclic And Heterocyclicaromatic Compounds Byrhodopseudomonas Palustris Strains, Gönül Çeti̇nkaya Dönmez, Ayten Öztürk Jan 1999

Biodegradation Of Homocyclic And Heterocyclicaromatic Compounds Byrhodopseudomonas Palustris Strains, Gönül Çeti̇nkaya Dönmez, Ayten Öztürk

Turkish Journal of Biology

Six strains were isolated from Lake Aksehir (Konya-Turkey) and identified as Rhodopseudomonas palustris on the basis of physiological and morphological characteristics. The strains grew phototrophically on a variety of aromatic compounds (under illuminated anaerobic conditions), namely, benzoate, hippurate, benzyl alcohol, 2-amino benzoic acid, phloroglucinol, phenylacetic acid, catechol, pyridine and pyrazoline. Biodegradation of 2-amino benzoate, phloroglucinol, catechol, pyridine and pyrazolin by Rhodopseudomonas palustrisstrains have not been reported in the literature.


Acute Lethal Toxicity And Accumulation Of Copper Ingammarus Pulex (L.) (Amphipoda), Kemal Güven, Cengi̇zhan Özbay, Erhan Ünlü, Ali̇ Satar Jan 1999

Acute Lethal Toxicity And Accumulation Of Copper Ingammarus Pulex (L.) (Amphipoda), Kemal Güven, Cengi̇zhan Özbay, Erhan Ünlü, Ali̇ Satar

Turkish Journal of Biology

Gammarus pulex (L.) collected from clean sites around Kabakli pond (Diyarbakır) was acclimatized at 15°C for 10 days. The individuals were placed in 1lt. vessels and exposed to Cu ++ concentrations of 0.05, 0.08, 0.10, 0.15, 0.20, 0.30 and 0.50 ppm to determine both 24, 48, 72 and 96 h LC50 values and Cu ++ accumulation over 96h. LC 50 values at 24, 48, 72 and 96 h were calculated to be 0.2, 0.17, 0.12 and 0.1 ppm, respectively. Acute copper accumulation in gammarids exposed to various copper concentrations over 96 h was determined using an atomic absorption spectrophotometer. An …


Contributions To The Pollen Morphology Of Thefamily Compositae, Anjum Perveen Jan 1999

Contributions To The Pollen Morphology Of Thefamily Compositae, Anjum Perveen

Turkish Journal of Biology

The pollen morphology of 24 species of Compositae belonging to 18 genera was examined by light and scanning microscopy. The present data confirms the eurypalynous nature of the family. Delimitation of the genera on the basis of pollen characters is less marked. Pollen grains usually radially symmetrical, isopolar rarely apolar; tricolporate, often porate. Shape commonly oblate-spheroidal to prolate-spheroidal, with some suboblate to subprolate types. Tectum echinate to echinolophate, often non-echinate. Tectum in-between the spines or spinules is sub-psilate, or perforated to striate. On the basis of the exine pattern, 4 distinct pollen types are recognized viz., Pollen type-I: Dicoma tomentosa, …


Acute Toxicity Of Zinc, Copper And Lead To Threespecies Of Marine Organisms From The Sinoppeninsula, Black Sea, Levent Bat, Ayşe Gündoğdu, Murat Sezgi̇n, Mehmet Çulha, Gamze Gönlügür, Mehmet Akbulut Jan 1999

Acute Toxicity Of Zinc, Copper And Lead To Threespecies Of Marine Organisms From The Sinoppeninsula, Black Sea, Levent Bat, Ayşe Gündoğdu, Murat Sezgi̇n, Mehmet Çulha, Gamze Gönlügür, Mehmet Akbulut

Turkish Journal of Biology

Acute toxicity tests were performed on Echinogammars olivii (Amphipoda), Sphaeroma serratum (Isopoda) and Palaemon elegans (Decapoda), from the Sinop Peninsula in the Black Sea. 96- h LC 50 values were estimated for copper, zinc and lead in these species using the static bioassay method. The LC 50 values of Cu for E. olivii, S. serratum and P. elegans were 0.25, 1.98 and 2.52 mg/l, respectively. The LC 50 values of Zn for E. olivii , S. serratum and P. elegans were 1.30, 6.12 and 12.3 mg/l, respectively. The LC 50 values of Pb for E. olivii, S. serratum and P. …


The Inhibition Of The Genotoxic Effects Ofenvironmental Pollutants And The Aging Processesby Plant Antimutagens, Urkhan Alekperov, Rena Gulieva, Ramiz Alekperov Jan 1999

The Inhibition Of The Genotoxic Effects Ofenvironmental Pollutants And The Aging Processesby Plant Antimutagens, Urkhan Alekperov, Rena Gulieva, Ramiz Alekperov

Turkish Journal of Biology

We investigated the effects of bioactive compounds obtained from fruits of Diospyros kaki L., Cydonia oblonga Mill. and roots of Glycyrrhiza glabra L., as well as their action in a complex mixture on the mutability in marrow cell chromosomes induced by genotoxicants (X-rays, N-Methyl-N-Nitrosurea, Cyclophosphamide) and aging. The plant products tested separately and in a complex mixture showed an ability to decrease the frequency of induced mutations in experimental animals. Antimutagenic properties of the complex mixture turned out to be considerably higher than its components separately. More antimutagenic activity of the mixture was revealed when mutagenesis was the result of …


On The Kinetics Of Human Erythrocyte Glutathionedisulfide Reductase: Does The Enzyme Really Play'ping-Pong'?, İ. Hamdi̇ Öğüş, Nazmi̇ Özer Jan 1999

On The Kinetics Of Human Erythrocyte Glutathionedisulfide Reductase: Does The Enzyme Really Play'ping-Pong'?, İ. Hamdi̇ Öğüş, Nazmi̇ Özer

Turkish Journal of Biology

: Human erythrocyte glutathione disulfide reductase studied at 37°C in 100 mM potassium phosphate buffer, pH 7.4, is subject to partial inhibition by GSSG at low [NADPH]. Saturation by NADPH is hyperbolic at low [GSSG] and becomes increasingly sigmoidal at high [GSSG]. NADP+ is a competitive inhibitor with respect to NADPH at 20-1000 µM GSSG and an uncompetitive inhibitor with respect to GSSG at 33-120 µM NADPH. Studied under special conditions (10 µM NADPH and 1000 µM GSSG), NADP+ exhibits a two-fold effect, inhibition being preceded by activation in the 0- 50 µM effector concentration range. The data are consistent …


Variation In The Nucleolus Organizer Regions (Nors)In Two Mole Rat Species ( Spalax Leucodon Andspalax Ehrenbergi), Mehmet Doğan Gülkaç, İlknur Şendoğdu Küçükdumlu Jan 1999

Variation In The Nucleolus Organizer Regions (Nors)In Two Mole Rat Species ( Spalax Leucodon Andspalax Ehrenbergi), Mehmet Doğan Gülkaç, İlknur Şendoğdu Küçükdumlu

Turkish Journal of Biology

In this investigation, patterns of variation in the nucleolus organizer regions (NORs) in the chromosomes of Spalax leucodon and Spalax ehrenbergi were studied. The chromosomal location of the Ag-NORs was determined in two mole rat species. S. leucodon has 3 pairs of nucleolar chromosomes, but S. ehrenbergi has only 2 pairs of nucleolar chromosomes in their whole chromosome sets. In both mole rat species, the chromosomal locations of Ag-NORs were determined to be on the terminal of the short arms of the subtelocentrics. The possibilty of Robertsonian translocation and the loss of paracentric NORs in S. ehrenbergi were discussed from …


Cytosolic Ca 2+ Levels In Co25 Myoblast Cells Bearinga Human N-Ras Oncogene After Stimulation By Thap-Sigarginand Growth Factors, Hülya Zeyti̇noğlu, Ian Gibson Jan 1999

Cytosolic Ca 2+ Levels In Co25 Myoblast Cells Bearinga Human N-Ras Oncogene After Stimulation By Thap-Sigarginand Growth Factors, Hülya Zeyti̇noğlu, Ian Gibson

Turkish Journal of Biology

The levels of intracellular calcium [Ca 2+ ]i were examined in CO25 myoblast cells bearing a mutated human N-ras oncogene, after stimulation by thapsigargin (ThG), bombesin and epidermal growth factor (EGF). Thapsigargin induced a [Ca 2+ ]i rise mostly from intracellular calcium pools, and a small Ca 2+ entry into cytoplasm via the plasma membrane channel. In both ras-induced and differentiated CO25 cells, [Ca 2+ ]i increase showed a similar pattern of events after addition of ThG. The addition of EGF and bombesin to both ras-induced and differentiated cells did not induce Ca 2+ mobilization, suggesting that the cells may …