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791.
792.
Inflammation induces the NF-κB dependent protein A20 in human renal proximal tubular epithelial cells (RPTEC), which secondarily contains inflammation by shutting down NF-κB activation. We surmised that inducing A20 without engaging the pro-inflammatory arm of NF-κB could improve outcomes in kidney disease. We showed that hepatocyte growth factor (HGF) increases A20 mRNA and protein levels in RPTEC without causing inflammation. Upregulation of A20 by HGF was NF-κB/RelA dependent as it was abolished by overexpressing IκBα or silencing p65/RelA. Unlike TNFα, HGF caused minimal IκBα and p65/RelA phosphorylation, with moderate IκBα degradation. Upstream, HGF led to robust and sustained AKT activation, which was required for p65 phosphorylation and A20 upregulation. While HGF treatment of RPTEC significantly increased A20 mRNA, it failed to induce NF-κB dependent, pro-inflammatory MCP-1, VCAM-1, and ICAM-1 mRNA. This indicates that HGF preferentially upregulates protective (A20) over pro-inflammatory NF-κB dependent genes. Upregulation of A20 supported the anti-inflammatory effects of HGF in RPTEC. HGF pretreatment significantly attenuated TNFα-mediated increase of ICAM-1, a finding partially reversed by silencing A20. In conclusion, this is the first demonstration that HGF activates an AKT-p65/RelA pathway to preferentially induce A20 but not inflammatory molecules. This could be highly desirable in acute and chronic renal injury where A20-based anti-inflammatory therapies are beneficial.  相似文献   
793.
Seed oils of meadowfoam (Limnanthes douglasii, L. alba) contain very long-chain fatty acids of strategic importance for a number of industrial applications. These include the monoene 20 15 and the diene 22:25,13. Engineering of meadowfoam-type oils in other oilseed crops is desirable for the production of these fatty acids as industrial feedstocks. Accordingly, we have targeted Brassica carinata and soybean (Glycine max) to trangenically engineer the biosynthesis of these unusual fatty acids. An L. douglasii seed-specific cDNA (designated Lim Des5) encoding a homolog of acyl-coenzyme A desaturases found in animals, fungi and cyanobacteria was expressed in B. carinata, which resulted in the accumulation of up to 10% 22:25,13 in the seed oil. In soybean, co-expression of Lim Des5 with a cDNA (Lim FAE1) encoding an FAEl (elongase complex condensing enzyme) homolog from L. douglasii resulted in the accumulation of 20:15 to approximately 10% of the total fatty acids of seeds. The content of C20 and C22 fatty acids was also increased from <0.5% in non-transformed soybean seeds to >25% in seeds co-expressing the Lim. douglasii Des5 and FAE1 cDNAs. In contrast, expression of the Lim Des5 in Arabidopsis did not produce the expected 20:25,11 in the seed oil. Cumulatively, these results demonstrate the utility of soybean and B. carinata for the production of vegetable oils containing novel C20 and C22 fatty acids, and confirm that the preferred substrates of the Lim Des5 are 20:0 and 22:13, respectively.  相似文献   
794.

Background and Aims

Brachypodium is a small genus of temperate grasses that comprises 12–15 species. Brachypodium distachyon is now well established as a model species for temperate cereals and forage grasses. In contrast to B. distachyon, other members of the genus have been poorly investigated at the chromosome level or not at all.

Methods

Twenty accessions comprising six species and two subspecies of Brachypodium were analysed cytogenetically. Measurements of nuclear genome size were made by flow cytometry. Chromosomal localization of 18–5·8–25S rDNA and 5S rDNA loci was performed by dual-colour fluorescence in situ hybridization (FISH) on enzymatically digested root-tip meristematic cells. For comparative phylogenetic analyses genomic in situ hybridization (GISH) applied to somatic chromosome preparations was used.

Key Results

All Brachypodium species examined have rather small genomes and chromosomes. Their chromosome numbers and genome sizes vary from 2n = 10 and 0·631 pg/2C in B. distachyon to 2n = 38 and 2·57 pg/2C in B. retusum, respectively. Genotypes with 18 and 28 chromosomes were found among B. pinnatum accessions. GISH analysis revealed that B. pinnatum with 28 chromosomes is most likely an interspecific hybrid between B. distachyon (2n = 10) and B. pinnatum (2n = 18). Two other species, B. phoenicoides and B. retusum, are also allopolyploids and B. distachyon or a close relative seems to be one of their putative ancestral species. In chromosomes of all species examined the 45S rDNA loci are distally distributed whereas loci for 5S rDNA are pericentromeric.

Conclusions

The increasing significance of B. distachyon as a model grass emphasizes the need to understand the evolutionary relationships in the genus Brachypodium and to ensure consistency in the biological nomenclature of its species. Modern molecular cytogenetic techniques such as FISH and GISH are suitable for comparative phylogenetic analyses and may provide informative chromosome- and/or genome-specific landmarks.  相似文献   
795.
Protein import into mitochondria involves several components of the mitochondrial outer and inner membranes as well as molecular chaperones located inside mitochondria. Here, we have investigated the effect of sulfhydryl group reagents on import of the in vitro transcribed/translated precursor of the F1 subunit of the ATP synthase (pF1) into Solanum tuberosum mitochondria. We have used a reducing agent, dithiothreitol (DTT), a membrane-permeant alkylating agent, N-ethylmaleimide (NEM), a non-permeant alkylating agent, 3-(N-maleimidopropionyl)biocytin (MPB), an SH-group specific agent and cross-linker 5,5-dithiobis-(2-nitrobenzoic acid) (DTNB) as well as an oxidizing cross-linker, copper sulfate. DTT stimulated the mitochondrial protein import, whereas NEM, MPB, DTNB and Cu2+ were inhibitory. Inhibition by Cu2+ could be reversed by addition of DTT. The efficiency of inhibition was higher in energized mitochondria than in non-energized. We have dissected the effect of the SH-group reagents on binding, unfolding and transport of the precursor into mitochondria. Our results demonstrated that the inhibitory effect of NEM, DTNB and Cu2+ on the efficiency of import was not due to the interaction of the SH-group reagents with import receptors. Modification of pF1 with NEM prior to the import resulted in stimulation of import, whereas DTNB and Cu2+ were inhibitory. NEM, MPB, DTNB and Cu2+ inhibited import of the NEM-modified pF1 into intact mitochondria. Import of pF1 through a receptor-independent bypass-route as well as import into mitoplasts were sensitive to DTT, NEM, MPB, DTNB and Cu2+ in a similar manner as import into mitochondria. As MPB does not cross the inner membrane, these results indicated that redox and conformational status of SH groups located on the outer surface of the inner mitochondrial membrane were essential for protein import.  相似文献   
796.
The aim of this study was to evaluate phenotypic variation of R0 androgenic plants obtained from four seed sources and donor plants by anther culture. Several morphological traits (leaf size, petiole length, leaf division, cortex colour) and the range of diversity were evaluated. There was large variation in all traits among the donor varieties. Especially leaf division and cortex colour differed significantly among the androgenic plants that came from different seed sources. The plants regenerated from four donor plants of variety 62 were significantly different in most traits except for leaf width and cortex colour. Evaluation of R1 plants will demonstrate whether the R0 variation observed is due to genetic variation or physiological differences from tissue culture.  相似文献   
797.
Pollen development and germination were adversely affected by the presence of mercury, whereas low-concentrations stimulated the whole procedure. Mercury caused morphological anomalies during the tube growth, characterized by irregularly increasing diameters and swelling tips. The main effect was the anomalous cell wall formation at the tip where a substantial number of organelles were found reducing the secretory vesicles. The dense organelle concentration caused a significant reduction of cytoplasmic movement integrity, and the cytosol streaming was gradually reduced or stopped completely. Electron dense, multilamellar myelin-like structures (MMS) of membranous material were frequently present, in close contact with plasmalemma or away from it. A loose network of fibrillar material and spherical aggregates mostly at the tip region were observed which progressively were loosened into the surrounding medium. Elevated mercury concentrations can affect plant reproduction, resulting in anomalies in gamete development and consequently loss of plant biodiversity.  相似文献   
798.

Objectives

Radiotherapy in patients with sinonasal mucosal melanoma (SNMM) was given as alternative treatment to surgery in cases with advanced, inoperable tumors or those not eligible for surgery. We presented the outcomes for patients with SNMM treated with radiotherapy alone.

Material and methods

The retrospective review of 6 consecutive SNMM (nasal cavity – 4 pts. and paranasal sinus – 2 pts.) patients (3 males and 3 females at mean age 64 years) treated between 2008 and 2016 was presented. The stage of disease was: T3 (1 pt.), T4a (3 pts.), T4b (2 pts.); with N0 and M0 in all patients. All patients underwent definitive primary photon radiotherapy (IMRT) alone; dose 66–72?Gy was delivered in 22–24 fractions given in 5 fractions (3?Gy) a week.

Results

The complete remission was observed in all our patients but only one patient survived 5 years without disease. Five patients died due to multiple distant metastases; two of those patients developed associated local recurrence 7–8 months after radiotherapy.

Conclusion

SNMM has a poor prognosis due to its high metastatic potential. Based on our numerically small report and data from literature we concluded that primary radiotherapy alone assured complete remission and even 5-year disease-free survival in only a few individual patients.  相似文献   
799.
Some sheep breeds are naturally prolific, and they are very informative for the studies of reproductive genetics and physiology. Major genes increasing litter size (LS) and ovulation rate (OR) were suspected in the French Grivette and the Polish Olkuska sheep populations, respectively. To identify genetic variants responsible for the highly prolific phenotype in these two breeds, genome-wide association studies (GWAS) followed by complementary genetic and functional analyses were performed. Highly prolific ewes (cases) and normal prolific ewes (controls) from each breed were genotyped using the Illumina OvineSNP50 Genotyping Beadchip. In both populations, an X chromosome region, close to the BMP15 gene, harbored clusters of markers with suggestive evidence of association at significance levels between 1E−05 and 1E−07. The BMP15 candidate gene was then sequenced, and two novel non-conservative mutations called FecXGr and FecXO were identified in the Grivette and Olkuska breeds, respectively. The two mutations were associated with the highly prolific phenotype (pFecXGr = 5.98E−06 and pFecXO = 2.55E−08). Homozygous ewes for the mutated allele showed a significantly increased prolificacy (FecXGr/FecXGr, LS = 2.50±0.65 versus FecX+/FecXGr, LS = 1.93±0.42, p<1E−03 and FecXO/FecXO, OR = 3.28±0.85 versus FecX+/FecXO, OR = 2.02±0.47, p<1E−03). Both mutations are located in very well conserved motifs of the protein and altered the BMP15 signaling activity in vitro using a BMP-responsive luciferase test in COV434 granulosa cells. Thus, we have identified two novel mutations in the BMP15 gene associated with increased LS and OR. Notably, homozygous FecXGr/FecXGr Grivette and homozygous FecXO/FecXO Olkuska ewes are hyperprolific in striking contrast with the sterility exhibited by all other known homozygous BMP15 mutations. Our results bring new insights into the key role played by the BMP15 protein in ovarian function and could contribute to a better understanding of the pathogenesis of women′s fertility disorders.  相似文献   
800.
Resistance to carbapenems is emerging, and it is a great problem to therapeutics. Seven multidrug-resistant (MDR) of Pseudomonas aeruginosa strains were isolated from urine and bronchial specimens. All isolates showed resistance to imipenem and meropenem (MIC; > or =16 mg/L). The resistance to carbapenems in two of seven strains was associated with the production of a metallo-beta-lactamases. Plasmids DNA probes were used to investigate the presence of genes coding for IMP-type enzymes. PCR experiments revealed that bla(IMP) genes were present in two isolates of Pseudomonas aeruginosa (MIC >32 microg/mL for both carbapenems).  相似文献   
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