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41.
The alder leaf beetle (Agelastica alni L., Coleoptera: Chrysomelidae) causes approximately 10% of total economic damage to hazelnut product per year in Turkey.
A. alni larvae are susceptible to several pathogens indigenous to the area in which these insects occur in Turkey. In the present
study, in order to find a more effective and safer biological control agent against this common pest, we evaluated the various
biological agents’ insecticidal activity during the four hazelnut seasons from 2002 to 2005 on the larvae of the alder leaf
beetle collected from the vicinity of Trabzon, Turkey. The tested agents are 25 insect-originating bacteria, 2 bacterial toxins
and 1 viral preparation. The results showed that the highest insecticidal activity was obtained by bacterial isolates at 1.8
× 109 bacteria/mL dose, within ten days on the larvae of A. alni. These are 90% for Bacillus thuringiensis biovar tenebrionis (4AA1), Bacillus sphaericus (Ar4, isolated from Anoplus roboris L., Col.: Curculionidae), and Bacillus thuringiensis (Mm2, isolated from Melolontha melolontha L., Col.: Scarabaeidae). Our results indicate that these isolates may be valuable as biological control agent. 相似文献
42.
Deniz S Wersinger E Schwab Y Mura C Erdelyi F Szabó G Rendon A Sahel JA Picaud S Roux MJ 《Journal of neurochemistry》2011,116(3):350-362
Lateral interactions at the first retinal synapse have been initially proposed to involve GABA by transporter-mediated release from horizontal cells, onto GABA(A) receptors expressed on cone photoreceptor terminals and/or bipolar cell dendrites. However, in the mammalian retina, horizontal cells do not seem to contain GABA systematically or to express membrane GABA transporters. We here report that mouse retinal horizontal cells express GAD65 and/or GAD67 mRNA, and were weakly but consistently immunostained for GAD65/67. While GABA was readily detected after intracardiac perfusion, it was lost during classical preparation for histology or electrophysiology. It could not be restored by incubation in a GABA-containing medium, confirming the absence of membrane GABA transporters in these cells. However, GABA was synthesized de novo from glutamate or glutamine, upon addition of pyridoxal 5'-phosphate, a cofactor of GAD65/67. Mouse horizontal cells are thus atypical GABAergic neurons, with no functional GABA uptake, but a glutamate and/or glutamine transport system allowing GABA synthesis, probably depending physiologically from glutamate released by photoreceptors. Our results suggest that the role of GABA in lateral inhibition may have been underestimated, at least in mammals, and that tissue pre-incubation with glutamine and pyridoxal 5'-phosphate should yield a more precise estimate of outer retinal processing. 相似文献
43.
We use the well-known structural and functional properties of the gramicidin A channel to test the appropriateness of force fields commonly used in molecular dynamics (MD) simulations of ion channels. For this purpose, the high-resolution structure of the gramicidin A dimer is embedded in a dimyristoylphosphatidylcholine bilayer, and the potential of mean force of a K(+) ion is calculated along the channel axis using the umbrella sampling method. Calculations are performed using two of the most common force fields in MD simulations: CHARMM and GROMACS. Both force fields lead to large central barriers for K(+) ion permeation, that are substantially higher than those deduced from the physiological data by inverse methods. In long MD simulations lasting over 60 ns, several ions are observed to enter the binding site but none of them crossed the channel despite the presence of a large driving field. The present results, taken together with many earlier studies, highlights the shortcomings of the standard force fields used in MD simulations of ion channels and calls for construction of more appropriate force fields for this purpose. 相似文献
44.
Avsar Timucin Kose Tansu Bilge Oksal Muhammed Deniz Turan Gizem Kilic Turker 《Molecular biology reports》2022,49(10):9241-9249
Molecular Biology Reports - Glioma is the most common type of brain tumors and isocitrate dehydrogenase (IDH1) gene is the most prominent molecular marker about the disease prognosis, response to... 相似文献
45.
Anil-Inevi Muge Sağlam-Metiner Pelin Kabak Evrim Ceren Gulce-Iz Sultan 《Molecular biology reports》2020,47(1):97-109
Molecular Biology Reports - Breast cancer is one of the most common cancer types among women in which early tumor invasion leads to metastases and death. EpCAM (epithelial cellular adhesion... 相似文献
46.
O-linked N-acetylglucosaminyltransferase (OGT)-mediated protein O-GlcNAcylation has been revealing various aspects of functional significance in biological processes, such as cellular signaling and activation of immune system. We found that OGT is maintained as S-nitrosylated form in resting cells, and its denitrosylation is triggered in innate immune response of lipopolysaccharide (LPS)-treated macrophage cells. S-nitrosylation of OGT strongly inhibits its catalytic activity up to more than 80% of native OGT, and denitrosylation of OGT leads to protein hyper-O-GlcNAcylation. Furthermore, blockage of increased protein O-GlcNAcylation results in significant loss of nitric oxide and cytokine production. We propose that denitrosylation of S-nitrosylated OGT is a direct mechanism for upregulation of OGT activity by which immune defense is critically controlled in LPS-stimulated innate immune response. 相似文献
47.
Kyong-Rock Do Young-Seok Cho Hyung-Keun Kim Byung-Hee Hwang Eun-Jung Shin Hae-Bin Jeong Sung-Soo Kim Hiun-Suk Chae Myung-Gyu Choi 《The Korean journal of parasitology》2010,48(1):75-78
The present study investigated characteristics of 24 parasite infection cases detected during colonoscopy in a regional hospital from January 2001 to December 2008. Sixteen patients were confirmed with Trichuris trichiura infection, 6 patients were with Ascaris lumbricoides infection, 1 patient with Enterobius vermicularis infection, and 1 patient with Anisakis infection. Among them, 7 patients (43.8%) were asymptomatic. Colonoscopy findings were normal in 18 patients (75.0%). Among the patients with T. trichiura infection, colonoscopy showed several erosions in 2 patients (8.3%) and non-specific inflammation of the affected segment of the colon in 3 patients (12.5%). In 1 patient with anisakiasis, colonoscopy revealed a markedly swollen colonic wall. Stool examinations were performed before treatment in 7 patients (29.2%) and were all negative for parasite eggs or worms. These results suggest that colonoscopy is a useful diagnostic approach for parasitic infections even for asymptomatic patients and for patients with negative stool examinations. 相似文献
48.
A Bayesian Analysis for Identifying DNA Copy Number Variations Using a Compound Poisson Process 总被引:1,自引:0,他引:1
Jie Chen Ayten Yiğiter Yu-Ping Wang Hong-Wen Deng 《EURASIP Journal on Bioinformatics and Systems Biology》2010,2010(1):268513-11
To study chromosomal aberrations that may lead to cancer formation or genetic diseases, the array-based Comparative Genomic Hybridization (aCGH) technique is often used for detecting DNA copy number variants (CNVs). Various methods have been developed for gaining CNVs information based on aCGH data. However, most of these methods make use of the log-intensity ratios in aCGH data without taking advantage of other information such as the DNA probe (e.g., biomarker) positions/distances contained in the data. Motivated by the specific features of aCGH data, we developed a novel method that takes into account the estimation of a change point or locus of the CNV in aCGH data with its associated biomarker position on the chromosome using a compound Poisson process. We used a Bayesian approach to derive the posterior probability for the estimation of the CNV locus. To detect loci of multiple CNVs in the data, a sliding window process combined with our derived Bayesian posterior probability was proposed. To evaluate the performance of the method in the estimation of the CNV locus, we first performed simulation studies. Finally, we applied our approach to real data from aCGH experiments, demonstrating its applicability. 相似文献
49.
Background
NOL7 is a candidate tumor suppressor that localizes to a chromosomal region 6p23. This locus is frequently lost in a number of malignancies, and consistent loss of NOL7 through loss of heterozygosity and decreased mRNA and protein expression has been observed in tumors and cell lines. Reintroduction of NOL7 into cells resulted in significant suppression of in vivo tumor growth and modulation of the angiogenic phenotype. Further, NOL7 was observed to localize to the nucleus and nucleolus of cells. However, the mechanisms regulating its subcellular localization have not been elucidated. 相似文献50.
Purification of aquarium water by PVA gel-immobilized photosynthetic bacteria during goldfish rearing 总被引:1,自引:0,他引:1
Soo Kyong Jeong Jeong-Sup Cho In-Soo Kong Hyun Do Jeong Joong Kyun Kim 《Biotechnology and Bioprocess Engineering》2009,14(2):238-247
This study was conducted to evaluate the ability of a PVA-gel beads filtration (PVA) system using photosynthetic bacteria
to purify water. To accomplish this, duplicate long-term goldfish rearing experiments were conducted using four different
types of aquarium systems (COF, PSB, EMC, and PVA). The results revealed that the concentrations of NH4
+-N on the day of a goldfish’s death were significantly higher than the concentrations on other days for all the aquarium systems.
In addition, the mean concentration of NH4
+-N during goldfish rearing occurred in the following order: COF system > EMC system > PSB system > PVA system. Furthermore,
the mean values of all other ion concentrations (NO3
−-N, NO2
−-N, and PO4
2−-P) were found to be lowest in the PVA system. As a result, there was more prominent decomposition of organic matter in the
aquarium tank containing the PVA system, as well as less turbid aquarium water and more active goldfish. Additionally, the
PVA-gel beads resulted in almost complete denitrification, even after six-months of goldfish rearing. To our knowledge, this
is the first study to report that PVA gel-immobilized photosynthetic bacteria have the ability to purify water. Overall, the
results of this study indicate that this immobilized photosynthetic bacteria system has the potential for use as a component
in circulating filtration systems. 相似文献