排序方式: 共有237条查询结果,搜索用时 15 毫秒
101.
Synthesis, structure, and antimicrobial studies of silver complexes of N-heterocyclic carbene (NHC) are reported. All the silver-NHC complexes (1a-f) were prepared from the benzimidazolium salts by the reactions with Ag2O in dichloromethane as a solvent at room temperature. The new compounds characterized by 1H NMR, 13 C NMR, IR and elemental analysis techniques which support the proposed structures. Chloro[1-(2,4,6-trimethylbenzyl)-3-(methoxyethyl)benzimidazol-2-ylidene]silver(I) complex was structurally characterized by single-crystal X-ray diffraction. A series of new Ag-NHC complexes were screened for their in vitro antimicrobial activity against a variety of Gram-positive and Gram-negative bacteria as well as for their antifungal activity against a Candida albicans and Candida tropicalis. 相似文献
102.
The first objective was to compare sperm quality following conventional manual sperm freezing (cryovials held 1, 2, 3, and 4 cm, respectively, above liquid nitrogen (LN2) for 10 min, resulting in cooling velocities of approximately −14.9, −10.1, −6.6, and −5.1 °C/min, respectively), and cooling velocities of −5, −20, −40, and −100 °C/min in a programmed automated freezer, for sperm recovered from CD-1, B6129SF1, and C57BL/6NCrlBR mice. Furthermore, using these strains, as well as 129S/SvPaslco, and DBA/2NCrlBR mice, the second objective was to determine the effects on DNA integrity of sperm exposed to hyposmotic (1 mOsm/L) and hyperosmotic (2400 mOsm/L) solutions, compared to an isosmotic control (300 mOsm/L). For freezing above LN2 or in an automated freezer, 2 cm above LN2 and −100 °C/min, respectively, were optimal (P < 0.05-0.01), with no significant differences between these two approaches for post-thaw progressive motility, DNA integrity, and in vitro rates of fertilization and blastocyst formation. Both manual and automated freezing techniques increased post-thaw sperm DNA fragmentation (P < 0.01); the DNA integrity of post-thaw sperm was significantly affected by cooling velocity and strain background. Relative to isosmotic controls, a hyposmotic solution was more deleterious (P < 0.05-0.01) to sperm DNA integrity than a hyperosmotic solution for CD-1, B6129SF1, C57BL/6, and DBA mice (there were strain-dependent differences). In conclusion, optimization of freezing distance and cooling velocity (manual and automated freezing, respectively) were significant factors for efficient cryopreservation and re-derivation of mice from frozen-thawed sperm. Additionally, osmotically-driven volume changes in mouse sperm increased DNA fragmentation, with susceptibility affected by background strain. 相似文献
103.
The catalytic domain of cytochrome P450 is thought to contact the lipid core of the endoplasmic reticulum membrane based on antibody epitope accessibility, protease susceptibility, and hydrophobic surfaces present on P450 structures of solubilized forms of the proteins. Quenching by nitroxide spin label-modified phospholipids of the fluorescence of tryptophan residues substituted into cytochrome P450 2C2, modified to contain tryptophan only at position 120, was used to identify regions of P450 inserted into the lipid core and to estimate the depth of penetration. Consistent with the proposed models of cytochrome P450-membrane interaction, the fluorescence of tryptophans inserted at residues 36 and 69 in the two segments of P450 2C2 flanking the A-helix and at residue 380 in the beta2-2 strand was quenched by nitroxide spin labels on carbon 5 of the fatty acid tails of the phospholipids within the lipid bilayer. The fluorescence of tryptophan at 380 was also strongly quenched by a spin label on carbon 12 of the fatty acids suggesting it was deepest in the membrane. However, fluorescence of tryptophan substituted at residue 225 in the F-G loop, which was predicted to be in the lipid bilayer, was not quenched by the spin labels at carbons 5 and 12 of the fatty acids. The pattern of quenching of fluorescence for tryptophans at the other positions tested, 80, 189, 239, and 347, was similar to the parent protein indicating they were not inserted into the lipid bilayer as expected. The results are consistent with an orientation of cytochrome P450 2C2 in the membrane in which positions 36, 69, and 380 are inserted into the lipid bilayer and residues 80 and 225 are near or within the phospholipid headgroup region. In this orientation, the F-G loop, which contains residue 225, could form a dimerization interface as was observed in the P450 2C8 crystal structure (Schoch, G. A., et al. (2004) J. Biol. Chem. 279, 9497). 相似文献
104.
105.
106.
Burcu Bayoglu Huseyin Altug Cakmak Husniye Yuksel Gunay Can Bilgehan Karadag Turgut Ulutin Vural Ali Vural Mujgan Cengiz 《Molecular and cellular biochemistry》2013,379(1-2):77-85
Metabolic syndrome (MetS) is a common multifactorial disorder that involves abdominal obesity, dyslipidemia, hypertension, and hyperglycemia. Genome-wide association studies have identified a major risk locus for coronary artery disease and myocardial infarction on chromosome 9p21. Here, we examined the frequency of single nucleotide polymorphisms (SNPs) on chromosome 9p21 in a sample of Turkish patients with MetS and further investigated the correlation between regional SNPs, haplotypes, and MetS. The real-time polymerase chain reaction (RT-PCR) was used to analyze 4 SNPs (rs10757274 A/G, rs2383207 A/G, rs10757278 A/G, rs1333049 C/G) in 291 MetS patients and 247 controls. Analysis of 4 SNPs revealed a significant difference in the genotype distribution for rs2383207, rs10757278, and rs1333049 between MetS patients and controls (p = 0.041, p = 0.005, p = 0.023, respectively) but not for rs10757274 (p = 0.211). MetS and control allelic frequencies for rs2383207, rs10757278, and rs1333049 were statistically different (p < 0.05). The rs2383207 AG variant, was identified as a MetS risk factor (p = 0.012, OR = 33.271; 95 % CI: 2.193–504.805) and the AA haplotype in block 1 and the GC, AG haplotypes in block 2 were associated with MetS (χ 2 = 3.875, p = 0.049; χ 2 = 9.334, p = 0.0022; χ 2 = 9.134, p = 0.0025, respectively). In this study, we found that chromosome 9p21 SNP rs10757278 and related haplotypes correlate with MetS risk. This is the first report showing an association between a 9p21 variant and MetS and suggests that rs10757278 polymorphism may confer increased risk for disease. 相似文献
107.
Songul Gurel Mehmet Cengiz Baloglu Ekrem Gurel Huseyin Avni Oktem Meral Yucel 《Plant Cell, Tissue and Organ Culture》2011,106(2):261-268
The effects of a two-stage pretreatment of seedlings on the subsequent shoot regeneration capacity were investigated. Pretreated
seedlings were obtained by germinating seeds on three different germination media and then further culturing on six different growth media. Lamina and petiole explants of two sugar beet (Beta
vulgaris L.) breeding lines were then excised from the pretreated seedlings and cultured on five different shoot regeneration media. In both breeding lines, petiole explants produced significantly more shoots than lamina explants with higher frequencies
of organogenic capacities; petiole explants of the lines M1195 and ELK345 produced a mean of 2.1 and 2.7 shoots per explant
while their lamina explants produced 1.5 and 2.2 shoots per explant, respectively. A genotypic variation was evident as the
line ELK345 was more productive for shoot development from both types of explants. In overall comparisons of different germination, growth and regeneration media, germination medium was most effective when supplemented with 0.5 mg/l 6-benzyladenine (BA) while both growth and regeneration
media were most productive when contained a combination of 0.25 mg/l BA and 0.10 mg/l indole-3-butyric acid (IBA). Of all
the treatments tested, the highest mean number of shoots per explant (8.3 shoots) and frequency of organogenic explants (75.6%)
were obtained on regeneration medium supplemented with 0.25 mg/l BA and 0.10 mg/l IBA when petiole explants of the line ELK345
were excised from the seedlings that had been germinated on medium containing 0.5 mg/l BA followed by further growth on medium
containing 0.25 mg/l BA and 0.10 mg/l IBA. 相似文献
108.
Oscar Diaz-Horta Duygu Duman Joseph Foster II Asl? S?rmac? Michael Gonzalez Nejat Mahdieh Nikou Fotouhi Mortaza Bonyadi Filiz Ba?ak Cengiz Ibis Menendez Rick H. Ulloa Yvonne J. K. Edwards Stephan Züchner Susan Blanton Mustafa Tekin 《PloS one》2012,7(11)
Identification of the pathogenic mutations underlying autosomal recessive nonsyndromic hearing loss (ARNSHL) is difficult, since causative mutations in 39 different genes have so far been reported. After excluding mutations in the most common ARNSHL gene, GJB2, via Sanger sequencing, we performed whole-exome sequencing (WES) in 30 individuals from 20 unrelated multiplex consanguineous families with ARNSHL. Agilent SureSelect Human All Exon 50 Mb kits and an Illumina Hiseq2000 instrument were used. An average of 93%, 84% and 73% of bases were covered to 1X, 10X and 20X within the ARNSHL-related coding RefSeq exons, respectively. Uncovered regions with WES included those that are not targeted by the exome capture kit and regions with high GC content. Twelve homozygous mutations in known deafness genes, of which eight are novel, were identified in 12 families: MYO15A-p.Q1425X, -p.S1481P, -p.A1551D; LOXHD1-p.R1494X, -p.E955X; GIPC3-p.H170N; ILDR1-p.Q274X; MYO7A-p.G2163S; TECTA-p.Y1737C; TMC1-p.S530X; TMPRSS3-p.F13Lfs*10; TRIOBP-p.R785Sfs*50. Each mutation was within a homozygous run documented via WES. Sanger sequencing confirmed co-segregation of the mutation with deafness in each family. Four rare heterozygous variants, predicted to be pathogenic, in known deafness genes were detected in 12 families where homozygous causative variants were already identified. Six heterozygous variants that had similar characteristics to those abovementioned variants were present in 15 ethnically-matched individuals with normal hearing. Our results show that rare causative mutations in known ARNSHL genes can be reliably identified via WES. The excess of heterozygous variants should be considered during search for causative mutations in ARNSHL genes, especially in small-sized families. 相似文献
109.
110.
IFN-gamma and IL-17 production in experimental autoimmune encephalomyelitis depends on local APC-T cell complement production 总被引:1,自引:0,他引:1
Liu J Lin F Strainic MG An F Miller RH Altuntas CZ Heeger PS Tuohy VK Medof ME 《Journal of immunology (Baltimore, Md. : 1950)》2008,180(9):5882-5889
IFN-gamma- and IL-17-producing T cells autoreactive across myelin components are central to the pathogenesis of multiple sclerosis. Using direct in vivo, adoptive transfer, and in vitro systems, we show in this study that the generation of these effectors in myelin oligodendrocyte glycoprotein(35-55)-induced experimental autoimmune encephalomyelitis depends on interactions of locally produced C3a/C5a with APC and T cell C3aR/C5aR. In the absence of the cell surface C3/C5 convertase inhibitor decay-accelerating factor (DAF), but not the combined absence of DAF and C5aR and/or C3aR on APC and T cells, a heightened local autoimmune response occurs in which myelin destruction is markedly augmented in concert with markedly more IFN-gamma(+) and IL-17(+) T cell generation. The augmented T cell response is due to increased IL-12 and IL-23 elaboration by APCs together with increased T cell expression of the receptors for each cytokine. The results apply to initial generation of the IL-17 phenotype because naive CD62L(high) Daf1(-/-) T cells produce 3-fold more IL-17 in response to TGF-beta and IL-6, whereas CD62L(high) Daf1(-/-)C5aR(-/-)C3aR(-/-) T cells produce 4-fold less. 相似文献