Genetic differentiation between clone collections and natural populations of European black poplar (<Emphasis Type="Italic">Populus nigra</Emphasis> L.) in turkey

The European black poplar (Populus nigra L.) is an ecologically and economically important tree species for Turkey. The important and major genetic resources of species for future breeding and ex situ conservation purposes have been archived in a clone bank in Ankara by selecting clones from natural populations and old plantations throughout Turkey. There is no study to date assessing genetic composition these materials. Two-hundred-thirty-three P. nigra clones from six geographic region of Turkey (clone collection populations), and 32 trees from two natural populations (Tunceli and Melet) were genotyped by using 12 nuclear microsatellite DNA markers. There were nine clones which duplicated in various frequencies. The analysis carried out with removal of the duplicated clones revealed a moderately high genetic diversity in studied populations. The observed heterozygosities ranged from 0.59 in Tunceli natural to 0.69 in Central Anatolia clone collection populations. In general, there was excess of heterozygosity in the studied populations. Populations composed of clone collections were significantly differentiated from natural populations (F _ST = 0.17), while there was little differentiation among those populations in the clone collection (F _ST = 0.03). Two distantly located natural populations with small sizes also differed from each other (F _ST = 0.17). Genetic structure analysis revealed two distinct groups (clone collection vs natural populations) with very high membership values (>92%). Clone collection populations had high level of admixture while natural populations had homogenous genetic structure. The presence of large number of clonal duplication, reduced genetic differentiation, and high level of admixture in clone collection populations indicate that genetic resources of European black poplar were highly degraded through genetic erosion and pollution caused by intensive cultural practices and extensive dispersal of clonal materials. To understand genetic diversity and its structural pattern thoroughly in the six clone collection populations, a further study with extensive and systematic sampling of European black poplar populations in major river ecosystems in Turkey will be useful.     

Is local distribution of the epiphytic lichen <Emphasis Type="Italic">Lobaria pulmonaria</Emphasis> limited by dispersal capacity or habitat quality?

By surveying and re-surveying 12 forest sites in southern Sweden for the epiphytic lichen Lobaria pulmonaria with a 9-year interval, and measuring tree-related habitat quality variables, we have investigated whether the local distribution of the lichen is limited by poor dispersal capacity or by habitat quality. Dispersal distances were measured indirectly as the distances between colonised trees and the nearest trees occupied by L. pulmonaria in both 1992 and 2001. To compare habitat quality between trees occupied by L. pulmonaria and neighbouring control trees, we recorded tree species and measured age and growth rate of trees, light conditions, bark structure and bryophyte cover. The estimated mean dispersal distance was 35 m, with a recorded maximum of 75 m. Occupied trees were larger and had a larger cover of bryophytes than unoccupied trees of similar size. The results indicate that dispersal capacity probably is the most important factor in limiting the local distribution of L. pulmonaria, but habitat-quality factors may be important on a smaller spatial scale.     

A biosensor based on catalase for determination of highly toxic chemical azide in fruit juices

In this work, an amperometric biosensor based on catalase enzyme was developed for the determination of azide. The principle of the measurements was based on the determination of the decrease in the differentiation of oxygen level which had been caused by the inhibition of catalase in the bioactive layer of the biosensor by azide. Firstly, the optimum conditions for the inhibitor biosensor were established. In the optimization studies of the biosensor, the most suitable catalase and gelatin amounts and glutaraldehyde ratio were determined. Optimum catalase activity, optimum gelatin amount and glutaraldehyde percentage were 5000 Ucm(-2), 5.94 mgcm(-2) and 2.5%, respectively. Characterization studies of the biosensor such as optimum pH and optimum temperature were carried out. The repeatability experiments were done and the average value (x), standard deviation (S.D.) and variation coefficient (C.V.) were calculated as 98.6 microM, +/-4.16 microM and 4.23%, respectively. A good linear relationship with a correlation coefficient of 0.9902 was obtained over the concentration range of 25 microM to 300 microM azide. After the optimization and characterization studies the proposed biosensor was applied to the determination of azide in certain fruit juices.     

Decrease in Hydraulic Conductivity of a Paddy Field using Biocalcification in situ

The hydraulic conductivity of a paddy field (Anthraquic Dystrustept), a silty clay soil containing more than 29% (w/w) of gravel, in Nagoya University Farm was reduced by in situ treatment of subsurface soil using bentonite and biocalcification (microbial calcium carbonate precipitation) through the addition of CaCl₂, urea, and corn steep liquor (CSL). The treatment decreased the hydraulic conductivity of the field from an average of 10^?3 cm/s to a range of 10^?5 to 10^?7 cm/s during 69 days, with reducing the proportion of pores of subsurface soil larger than 75 µm in diameter. The biocalcification effect was observed at 10-cm thickness from the treated subsurface. Laboratory soil core experiments demonstrated that the decrease in the hydraulic conductivity was not attributed to the effect of bentonite but mainly to the effect of biocalcification. The addition of CSL enhanced the urease activity of soil required for biocalcification, even at 4°C, as indicated by a decrease in urease activation energy temperature sensitivity. These experimental results agreed with the gradual decrease in hydraulic conductivity observed in the field when the average daily temperature was 7°C (days 24–69). It was suggested that the biocalcification is a potential technique to reduce the hydraulic conductivity of paddy field.     

Barley microgreen incorporation in diet-controlled diabetes and counteracted aflatoxicosis in rats

Increased environmental pollution and unhealthy lifestyle are blamed for escalated chronic diseases. Exposure to aflatoxins was recently suggested to have a role in the increased incidence of type 2 diabetes mellitus. Diet modification and consumption of different functional food are now gaining attention, especially in diabetes management. This study investigates the effect of a diet containing barley microgreen against diabetes induced by streptozotocin with or without aflatoxin administration in rats. Barley microgreen was rich in 3′-Benzyloxy-5,6,7,4′-tetramethoxyflavone (48.8% of total) followed by 5β,7βH,10α-Eudesm-11-en-1α-ol (18.46%). Streptozotocin injection and/or aflatoxin administration significantly elevated glucose level, decreased insulin level, decreased β-cell function, deteriorated liver and kidney function parameters, and induced oxidative stress in the liver. Histopathology revealed irregular small-sized islets and decreased area % of insulin-positive beta cells in the pancreas, hepatic degeneration, nephropathy, and neuropathy in diabetic and/or aflatoxin administered rats compared to control. Barley microgreen diet fed to diabetic rats with or without aflatoxin alleviated all evaluated parameters. Barley microgreen diet also ameliorated the toxic effect of aflatoxin. In conclusion, exposure to aflatoxin aggravated diabetes and its complication. The incorporation of barley microgreen in the diet was able to control type 2 diabetes mellitus and the improved outcomes observed with barley microgreen treatments involved or occurred in conjunction with improved biomarkers of oxidative stress.     

Utilizing peanut husk (Arachis hypogaea L.) in the manufacture of medium-density fiberboards

The main objective of this study was to investigate the potential of peanut husk (Arachis hypogaea L.) as a fiber–peanut mixture to produce fiberboards for general purposes. For panel production, the addition of peanut husk at various percentages to the wood fiber was the only variable. Panels produced utilizing peanut husk were compared to panels produced using 100% wood fiber. The chemical properties of peanut husk; holocellulose and lignin content, alcohol–benzene, hot and cold water, and dilute alkali (1% NaOH) solubility, were also determined. Results indicated that panels could be produced utilizing up to 30% peanut husk without affecting the usability of the panels. It was not possible to meet the minimum IB strength standards when peanut husk was added to the mixture. Higher additions resulted in panels having lower elastic and rupture moduli than the minimum requirements according to TS-EN standards.     

Cytotoxic activities of Hypericum perforatum L. extracts against 2D and 3D cancer cell models

Cytotechnology - Six extracts were obtained from plant species Hypericum perforatum L., collected at Samsun in Turkey. The aim of this study was to examine the mechanisms of the anticancer activity...     

In vitro induction of neoantigen-specific T cells in myelodysplastic syndrome,a disease with low mutational burden

Therapies that utilize immune checkpoint inhibition work by leveraging mutation-derived neoantigens and have shown greater clinical efficacy in tumors with higher mutational burden. Whether tumors with a low mutational burden are susceptible to neoantigen-targeted therapy has not been fully addressed. To examine the feasibility of neoantigen-specific adoptive T-cell therapy, the authors studied the T-cell response against somatic variants in five patients with myelodysplastic syndrome (MDS), a malignancy with a very low tumor mutational burden. DNA and RNA from tumor (CD34⁺) and normal (CD3⁺) cells isolated from the patients’ blood were sequenced to predict patient-specific MDS neopeptides. Neopeptides representing the somatic variants were used to induce and expand autologous T cells ex vivo, and these were systematically tested in killing assays to determine the proportion of neopeptides yielding neoantigen-specific T cells. The authors identified a total of 32 somatic variants (four to eight per patient) and found that 21 (66%) induced a peptide-specific T-cell response and 19 (59%) induced a T-cell response capable of killing autologous tumor cells. Of the 32 somatic variants, 11 (34%) induced a CD4⁺ response and 11 (34%) induced a CD8⁺ response that killed the tumor. These results indicate that in vitro induction of neoantigen-specific T cells is feasible for tumors with very low mutational burden and that this approach warrants investigation as a therapeutic option for such patients.