排序方式: 共有95条查询结果,搜索用时 0 毫秒
21.
22.
Familial Mediterranean fever (FMF) is an autosomal recessive disorder characterized by recurrent attacks of fever and serositis. Mutations in the Mediterranean fever gene (MEFV) localized on the short arm of chromosome 16 cause FMF. Over 90 MEFV missense/nonsense mutations have been identified so far in FMF patients, mostly in the 10th exon of the gene. 相似文献
23.
Aydin M Gencer M Cetinkaya Y Ozkok E Ozbek Z Kilic G Orken C Tireli H Kara I 《IUBMB life》2006,58(3):165-172
We investigated the association of PON1 55/192 polymorphisms with type, severity and prognosis of stroke and oxidative markers. Paraoxonase1 (PON1), Glutathione Reductase (GSH-Rd) and Malondialdehyde (MDA) levels were measured at day 1 and at day 5 following the onset of stroke. Genotypes were determined by polymerase chain reaction and restriction digestion. The frequencies of QQ and MM genotypes of PON1 192 and PON1 55, respectively, were significantly higher in controls than in patients. However, the allele frequencies of PON1 192 R and PON1 55 L were significantly more frequent in patients compared to controls. The frequency of combined genotype of RR/LL was significantly higher in cardioembolic group than in atherothrombotic group. PON1 activities were significantly diminished in stroke patients compared to controls. In contrast, serum MDA levels were significantly greater in patients than the values in controls. GSH-Rd activity was higher in patients with small lesion and good prognosis than those with large and poor prognosis. Low density lipoprotein (LDL) levels in patients with large lesions were higher than those with small lesions. PON1 55/192 polymorphisms influence activity of the enzyme. PON1 55/192 genotypes have been associated with MDA levels. In conclusion, PON1 genetic variations are associated with risk factors, severity, type and prognosis of stroke and oxidative stress. 相似文献
24.
Alpha-amylase was produced from Penicillium griseofulvum by an SSF technique. Alpha-amylase was immobilized on Celite by an adsorption method. Various parameters, such as effect of pH and temperature, substrate concentration, operational and storage stability, ability to hydrolyze starch and products of hydrolysis were investigated; these findings were compared with the free enzyme. The activity yield of immobilization was 87.6%. The optimum pH and temperature for both enzymes were 5.5 degrees C and 40 degrees C, respectively. The thermal, and the operational and storage stabilities of immobilized enzyme were better than that of the free enzyme. Km and Vmax were calculated from Lineweaver-Burk plots for both enzymes. Km values were 9.1 mg mL(-1) for free enzyme, and 7.1 mg mL(-1) for immobilized enzyme. The Vmax of the immobilized enzyme was approximately 40% smaller than that of the free enzyme. The hydrolysis ability of the free and immobilized enzyme were determined as 99.3% and 97.9%, respectively. Hydrolysis products of the a-amylase from P. griseofulvum were maltose, unidentified oligosaccharides, and glucose. 相似文献
25.
Hakan Erdem Zeliha Kocak-Tufan Omer Yilmaz Zuhal Karakurt Aykut Cilli Hulya Turkan Ozlem Yazicioglu-Mocin Nalan Adıguzel Gokay Gungor Canturk Taşcı Gulden Yilmaz Oral Oncul Aygul Dogan-Celik Ozcan Erdemli Nefise Oztoprak Yakup Tomak Asuman Inan Demet Tok Sibel Temur Hafize Oksuz Ozgur Senturk Unase Buyukkocak Fatma Yilmaz-Karadag Derya Ozturk-Engin Dilek Ozcengiz Ahmet Karakas Hayati Bilgic Hakan Leblebicioglu 《Annals of clinical microbiology and antimicrobials》2014,13(1):1-5
Background
Burkholderia cepacia complex (BCC) bacteria are highly virulent, typically multidrug-resistant, opportunistic pathogens in cystic fibrosis (CF) patients and other immunocompromised individuals. B. vietnamiensis is more often susceptible to aminoglycosides than other BCC species, and strains acquire aminoglycoside resistance during chronic CF infection and under tobramycin and azithromycin exposure in vitro, apparently from gain of antimicrobial efflux as determined through pump inhibition. The aims of the present study were to determine if oxidative stress could also induce aminoglycoside resistance and provide further observations in support of a role for antimicrobial efflux in aminoglycoside resistance in B. vietnamiensis.Findings
Here we identified hydrogen peroxide as an additional aminoglycoside resistance inducing agent in B. vietnamiensis. After antibiotic and hydrogen peroxide exposure, isolates accumulated significantly less [3H] gentamicin than the susceptible isolate from which they were derived. Strains that acquired aminoglycoside resistance during infection and after exposure to tobramycin or azithromycin overexpressed a putative resistance-nodulation-division (RND) transporter gene, amrB. Missense mutations in the repressor of amrB, amrR, were identified in isolates that acquired resistance during infection, and not in those generated in vitro.Conclusions
These data identify oxidative stress as an inducer of aminoglycoside resistance in B. vietnamiensis and further suggest that active efflux via a RND efflux system impairs aminoglycoside accumulation in clinical B. vietnamiensis strains that have acquired aminoglycoside resistance, and in those exposed to tobramycin and azithromycin, but not hydrogen peroxide, in vitro. Furthermore, the repressor AmrR is likely just one regulator of the putative AmrAB-OprM efflux system in B. vietnamiensis. 相似文献26.
Gizem Kursunluoglu Hulya Ayar Kayali Dilek Taskiran 《Cell biochemistry and biophysics》2014,69(3):707-716
Cisplatin accumulates in mitochondria, which is a potent and widely used chemotherapeutic agent. In order to clarify the potential effect of cisplatin on electron transport chain (ETC), the variation of succinate dehydrogenase (SDH) and cytochrome c oxidase (COX) enzyme activities, nucleotide levels, as well as catalase (CAT) enzyme and membrane lipid peroxidation (LPO) level with respect to liver and kidney of cisplatin-exposed rats were studied. We found that cisplatin caused significant impairment in the SDH, COX, and CAT activities, and nucleotide levels associated with membrane LPO in isolated mitochondria. It was determined whether capsaicin, as an antioxidant, has a possible protective role on all investigated parameters of liver and kidney induced by cisplatin. The results of capsaicin + cisplatin suggest that capsaicin have antioxidant capacity to scavenge ROS to prevent membrane damage. 相似文献
27.
Marion Failler Heon?Yung Gee Pauline Krug Kwangsic Joo Jan Halbritter Lilya Belkacem Emilie Filhol Jonathan?D. Porath Daniela?A. Braun Markus Schueler Amandine Frigo Olivier Alibeu Cécile Masson Karine Brochard Bruno Hurault?de?Ligny Robert Novo Christine Pietrement Hulya Kayserili Rémi Salomon Marie-Claire Gubler Edgar?A. Otto Corinne Antignac Joon Kim Alexandre Benmerah Friedhelm Hildebrandt Sophie Saunier 《American journal of human genetics》2014,94(6):905-914
Ciliopathies are a group of hereditary disorders associated with defects in cilia structure and function. The distal appendages (DAPs) of centrioles are involved in the docking and anchoring of the mother centriole to the cellular membrane during ciliogenesis. The molecular composition of DAPs was recently elucidated and mutations in two genes encoding DAPs components (CEP164/NPHP15, SCLT1) have been associated with human ciliopathies, namely nephronophthisis and orofaciodigital syndrome. To identify additional DAP components defective in ciliopathies, we independently performed targeted exon sequencing of 1,221 genes associated with cilia and 5 known DAP protein-encoding genes in 1,255 individuals with a nephronophthisis-related ciliopathy. We thereby detected biallelic mutations in a key component of DAP-encoding gene, CEP83, in seven families. All affected individuals had early-onset nephronophthisis and four out of eight displayed learning disability and/or hydrocephalus. Fibroblasts and tubular renal cells from affected individuals showed an altered DAP composition and ciliary defects. In summary, we have identified mutations in CEP83, another DAP-component-encoding gene, as a cause of infantile nephronophthisis associated with central nervous system abnormalities in half of the individuals. 相似文献
28.
Bukulmez H Fife M Tsoras M Thompson SD Twine NA Woo P Olson JM Elston RC Glass DN Colbert RA 《Arthritis research & therapy》2005,7(2):R285-R290
Juvenile rheumatoid arthritis (JRA) comprises a group of chronic systemic inflammatory disorders that primarily affect joints
and can cause long-term disability. JRA is likely to be a complex genetic trait, or a series of such traits, with both genetic
and environmental factors contributing to the risk for developing the disease and to its progression. The HLA region on the
short arm of chromosome 6 has been intensively evaluated for genetic contributors to JRA, and multiple associations, and more
recently linkage, has been detected. Other genes involved in innate and acquired immunity also map to near the HLA cluster
on 6p, and it is possible that variation within these genes also confers risk for developing JRA. We examined the TPSN gene, which encodes tapasin, an endoplasmic reticulum chaperone that is involved in antigen processing, to elucidate its
involvement, if any, in JRA. We employed both a case–control approach and the transmission disequilibrium test, and found
linkage and association between the TPSN allele (Arg260) and the systemic onset subtype of JRA. Two independent JRA cohorts were used, one recruited from the Rheumatology
Clinic at Cincinnati Children's Hospital Medical Center (82 simplex families) and one collected by the British Paediatric
Rheumatology Group in London, England (74 simplex families). The transmission disequilibrium test for these cohorts combined
was statistically significant (χ2 = 4.2, one degree of freedom; P = 0.04). Linkage disequilibrium testing between the HLA alleles that are known to be associated with systemic onset JRA did
not reveal linkage disequilibrium with the Arg260 allele, either in the Cincinnati systemic onset JRA cohort or in 113 Caucasian
healthy individuals. These results suggest that there is a weak association between systemic onset JRA and the TPSN polymorphism, possibly due to linkage disequilibrium with an as yet unknown susceptibility allele in the centromeric part
of chromosome 6. 相似文献
29.
The regulatory effect of melatonin on physiological,biochemical and molecular parameters in cold-stressed wheat seedlings 总被引:1,自引:0,他引:1
Hulya Turk Serkan Erdal Mucip Genisel Okkes Atici Yavuz Demir Derya Yanmis 《Plant Growth Regulation》2014,74(2):139-152
We investigated the possible mediatory role of melatonin in protecting wheat plants from cold stress. Ten-day-old wheat seedlings were pretreated with 1 mmol l?1 melatonin for 12 h and subsequently exposed to stress conditions at 5/2 °C (day/night) for 3 days. Cold stress caused serious reductions in leaf surface area, water content, and photosynthetic pigment content, whereas melatonin application attenuated these reductions. Accumulation of reactive oxygen species (ROS), including superoxide and hydrogen peroxide, was very high in cold-stressed plants and caused lipid peroxidation in membranes. Concomitantly, ROS damaged the DNA profile and negatively influenced expression and/or activity of many enzymes, including RuBisCo. When compared to controls, cold-stressed plants had higher activities of the antioxidant enzymes superoxide dismutase, guaicol peroxidase, ascorbate peroxidase, and glutathione reductase and higher levels of the antioxidant compounds total ascorbate, reduced ascorbate, total glutathione, reduced glutathione, and phenolic substances; however, this elevation could not cope with the destructive effects of cold stress. Melatonin-pretreated plants exhibited greater increases in these parameters comparison with untreated cold-stressed plants. Isozyme bands monitored in native gel and RuBisCo expression supported these changes. Also, due to the cold-induced increase in dehydroascorbate and oxidized glutathione, the corrupted redox status in the cell was ameliorated by melatonin application. Similarly, levels of the osmoprotectants total soluble protein, carbohydrate, and proline were also increased by cold stress; however, melatonin-applied seedlings had a higher content of these solutes in comparison to untreated cold-stressed plants. We suggest that melatonin can improve plant resistance to cold stress in wheat seedlings by directly scavenging ROS and by modulating redox balance and other defence mechanisms. 相似文献
30.
This study was carried out in 52 non-diabetic, 62 diabetic patients with coronary artery disease (CAD) and 55 controls. A
Gly to Ser change RAGE gene was analyzed by PCR-RFLP techniques. GlyGly genotype frequency is higher in non-diabetics versus
controls (P < 0.001). GlySer frequency is higher in diabetics than controls and non-diabetics (P < 0.001). Ser allele frequency is respectively increased in the order of diabetics > Controls > non-diabetics. These results
reveals none association between Gly82Ser and the development of disease in non-diabetic patients. In diabetics with Ser allele,
higher prevalence of left-ventricule-hypertrophy was observed, but the significant difference between Gly82Ser and left-ventricule-hypertrophy
only found in the whole patient group. As a result Ser allele has much more importance in the development of left-ventricule-hypertrophy
than other cardiovascular risk factors. In this study we found the presence of Gly allele contributes to the CAD in non-diabetics
and Ser allele may contribute to disease in diabetics. 相似文献