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71.
Fourteen endemic and two sub-endemic species belonging to three subfamilies of Tettigoniidae (Tettigoniinae, Bradyporinae and Saginae) were sampled during field trips throughout the different ranges of Anatolia between the years of 2004 and 2013. Acoustic parameters of these 16 species affiliated to 8 genera (Anterastes, Apholidoptera, Gampsocleis, Parapholidoptera, Pezodrymadusa, Psorodonotus, Bradyporus and Saga) have been described for the first time in this study. Acoustical analysis showed that song characters are species-specific in the genera Saga and Psorodonotus. On the other hand, we could not find big differences among species of the genus Pezodrymadusa and Parapholidoptera castaneoviridis species-group.  相似文献   
72.

Background

Chlamydia pecorum is the causative agent of a number of acute diseases, but most often causes persistent, subclinical infection in ruminants, swine and birds. In this study, the genome sequences of three C. pecorum strains isolated from the faeces of a sheep with inapparent enteric infection (strain W73), from the synovial fluid of a sheep with polyarthritis (strain P787) and from a cervical swab taken from a cow with metritis (strain PV3056/3) were determined using Illumina/Solexa and Roche 454 genome sequencing.

Results

Gene order and synteny was almost identical between C. pecorum strains and C. psittaci. Differences between C. pecorum and other chlamydiae occurred at a number of loci, including the plasticity zone, which contained a MAC/perforin domain protein, two copies of a >3400 amino acid putative cytotoxin gene and four (PV3056/3) or five (P787 and W73) genes encoding phospholipase D. Chlamydia pecorum contains an almost intact tryptophan biosynthesis operon encoding trpABCDFR and has the ability to sequester kynurenine from its host, however it lacks the genes folA, folKP and folB required for folate metabolism found in other chlamydiae. A total of 15 polymorphic membrane proteins were identified, belonging to six pmp families. Strains possess an intact type III secretion system composed of 18 structural genes and accessory proteins, however a number of putative inc effector proteins widely distributed in chlamydiae are absent from C. pecorum. Two genes encoding the hypothetical protein ORF663 and IncA contain variable numbers of repeat sequences that could be associated with persistence of infection.

Conclusions

Genome sequencing of three C. pecorum strains, originating from animals with different disease manifestations, has identified differences in ORF663 and pseudogene content between strains and has identified genes and metabolic traits that may influence intracellular survival, pathogenicity and evasion of the host immune system.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-23) contains supplementary material, which is available to authorized users.  相似文献   
73.
This study reports the preparation and investigation of the modes of binding of the two symmetric 3,6‐diaminoacridine derivatives obtained from proflavine, which are 3,6‐diphenoxycarbonyl aminoacridine and 3,6‐diethoxycarbonyl aminoacridine to human serum albumin (HSA). The interaction of HSA with the derivatives was investigated using fluorescence quenching and ultraviolet‐visible absorption spectra at pH 7.2 and different temperatures. The results suggest that the derivatives used can interact strongly with HSA and are the formation of HSA‐derivative complexes and hydrophobic interactions as the predominant intermolecular forces in stabilizing for each complex. The Stern‐Volmer quenching constants, binding constants, binding sites and corresponding thermodynamic parameters ΔH, ΔS and ΔG were calculated at different temperatures. The binding distance (r) ~ 3 nm between the donor (HSA) and acceptors (3,6‐diethoxycarbonyl aminoacridine, 3,6‐diphenoxycarbonyl aminoacridine and proflavine) was obtained according to Förster's non‐radiative energy transfer theory. Moreover, the limit of detection and limit of quantification of derivatives were calculated in the presence of albumin. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
74.
75.
Excision Repair Cross-Complementing Group 1 (ERCC1) is an important DNA repair gene, playing critical role in nucleotide excision repair pathway and having a significant influence on genomic instability. Some studies support that ERCC1 might be a potential predictive and prognostic marker in non-small cell lung cancer (NSCLC). ERCC1 has also been shown to be a promising biomarker in NSCLC treated with a cisplatin-based regimen. Therefore, the determination of ERCC1 expression at DNA, mRNA and protein level in different stages of NSCLC is still an important topic in the cancer. Ninety-one formalin-fixed paraffin-embedded tumor samples histopathologically diagnosed as NSCLC were examined in this study. ERCC1 expression at protein level were scored by immunohistochemistry. The gene amplification and mRNA expression levels for ERCC1 were determined by real-time quantitative PCR. There was complete concordance among the three methods in 39 tumor samples (42.9%). A strong correlation was found between DNA amplification and mRNA expression (r = 0.662) while there was no correlation between mRNA and protein assessment for ERCC1 expression (r = −0.013). ERCC1 expression at mRNA and DNA level (63.1 and 84.2%, respectively) in tumors at stage III was higher than at the other stages. In contrast, the protein expression at stage II and III (56.6 and 52.6%, respectively) of NSCLC was lower than that of tumors with stage I NSCLC. These results show that the mechanism by which ERCC1 expression might play a role in tumor behavior. This study was also confirmed that the appropriate validation and qualification in methods used for ERCC1 status were needed before its clinical application and implementation.  相似文献   
76.
We investigated whether the severity of blood-brain barrier disruption caused by pentylenetetrazole-induced seizures is modified by long-term nitric oxide synthase inhibition in rats. Rats were given N-omega-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, in drinking water for 4 weeks, and then treated with pentylenetetrazole to induce seizures. Damage to the blood-brain barrier was investigated using Evans blue dye extravasation. Serum nitric oxide concentration was decreased in L-NAME-treated rats (P<0.01). L-NAME and/or pentylenetetrazole treatments elevated systolic blood pressure of animals (P<0.01). L-NAME caused an increase in the mortality rate after pentylenetetrazole injection leading to the death of animals at about 15 min after the onset of the seizure. Pentylenetetrazole-induced seizures in rats treated with L-NAME caused a significant increase in Evans blue dye extravasation into cerebral cortex, diencephalon and cerebellum, as compared with seizures evoked by pentylenetetrazole injection to L-NAME-untreated rats (P<0.01). Data presented here suggest that the degree of blood-brain barrier disruption induced by seizures is more pronounced in long-term nitric oxide deficiency.  相似文献   
77.
A modified Sihler's stain technique was used to visualize the branching patterns of oculomotor and trochlear nerves. The levator palpebrae, superior rectus, inferior rectus, medial rectus, inferior oblique, superior oblique and tensor trochlea muscles were isolated from the eyes of normal rabbits and processed using modified Sihler's technique. The distributions and terminal ramifications of the oculomotor and trochlear nerves were observed. Two distinct divisions and terminal branches of the oculomotor nerve were shown in detail together with the trochlear nerve distribution. The application of Sihler's technique enables researchers to trace nerve branching within relatively transparent muscles, whereas the nerve fibers are counterstained and clearly visible. This technique could be useful for detailed studies of the motor control of extraocular muscles.  相似文献   
78.
We isolated an antitumor glucan (HA beta-glucan) from the neutral polysaccharide fraction (A3) of a hot-water extract of the edible mushroom P. ostreatus (Fr.) Quél. Purification was accomplished by extractions with 20% sodium chloride solution saturated with thymol and by precipitations with ethanol from dimethyl sulfoxide solution. The glucan showed marked antitumor activity at a dose of 0.1 mg/kg. It is a highly branched (1----3)-beta-glucan having an average structure represented by a pentasaccharide segment consisting of one nonreducing terminal, one 3,6-di-O-substituted, and three 3-mono-O-substituted beta-D-glucopyranosyl residues. This structure was confirmed by examining 13C-n.m.r. spectra taken at 75.46 MHz.  相似文献   
79.
Xanthomonas oryzae pv. oryzae (Xoo) is the most devastating pathogen to Oryza sativa and has been shown to cause bacterial blight. Two bioactive compounds showing antimicrobial activities against Xoo strain KACC 10331 were isolated from a Streptomyces bottropensis strain. The ethyl acetate extract was fractionated on a Sephadex LH-20 column, and then purified by preparative HPLC. The purified compounds were identified as bottromycin A2 and dunaimycin D3S by HR/MS and 1H NMR analyses. The MIC value against Xoo and the lowest concentration still capable of suppressing rice bacterial blight were 2 microgram/ml and 16 microgram/ml for bottromycin A2, and 64 microgram/ml and 0.06 microgram/ml for dunaimycin D3S, respectively. These two compounds were shown to exert different bioactivities in vitro and in rice leaf explants.  相似文献   
80.
We have analyzed the manner of incorporation of bile acid into lipid bilayers and resultant perturbation of the bilayer structure with lower bile acid/lipid ratios relevant to the physiological conditions (approximately 1 mM) by 2H and 31P NMR methods, as an aid to understanding the possible role as an endogenous tumor promoter in colon cancer besides the primary physiological function of solubilizing lipids. On the basis of the 2H quadrupole splittings of [6,6,7,7,8-2H5]deoxycholate and [11,11,12,12-2H4]chenodeoxycholate in the presence of lamellar multibilayers of egg yolk lecithin, these bile acids were found to be incorporated in such a manner that the B-D rings lie parallel with the normal of the bilayers when the ratio of the bile acid to lipid is low (less than 0.11). When the ratio is increased, these bile acid molecules are not dispersed entirely in the bilayer but aggregate to form micelles with lipids. Further, we studied the resultant perturbation of the multibilayers of egg yolk lecithin analyzed by using the 2H quadrupole splitting of [18,18,18-2H3]stearic acid as a probe and by 31P chemical shift anisotropy. We found that the bilayer structure is retained even at the bile acid-to-lipid ratio of 0.25, although a small amount of an isotropic phase appeared such as small vesicles and micelles. The molecular ordering of fatty acyl chains was rather enhanced by the presence of 1 mM deoxycholate in erythrocyte ghosts as seen from the 2H quadrupole splitting of [16,16,16-2H3]palmitic acid, although deoxycholate caused hemolysis in this condition. The former observation can be explained by the way the lipid-protein interaction is modified by deoxycholate located in the interface between the lipids and proteins.  相似文献   
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