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51.
Lung cancer, a complex neoplasm of lung tissue, is influenced by several environmental and genetic factors which could be changed in each individual. Aurora-A gene is related to mitotic events such as: chromosome instability, cell cycle regulation, spindle formation, and kinetechore-microtubule connections. This centrosomic serine/threonine kinase provides a strong connection between mitotic errors and carcinogenesis. The genomic alterations such as single nucleotide polymorphisms (SNPs) can exist in molecular pathways of lung cancer. Therefore, we evaluated the role of genetic polymorphisms of Aurora-A gene in the lung cancer in the Turkish population. Genotypes of five Aurora-A polymorphisms (F31I, V57I, 6328G/A, P50L, and S104L) were determined in 102 healty controls and 102 new diagnosed lung cancer cases. All samples were genotyped with DNA sequence technique. There were not any genotype variations in P50L, S104L, and 6328G/A polymorphisms. The frequencies of both genotypes F31I and V57I in lung cancer patients were not significantly different from those in controls (p > 0.05). A multivariable logistic regression analysis including patient characteristics, such as age and gender, did not change the results.  相似文献   
52.
The aim of this study was to describe the epidemiological and clinical features of an outbreak due to Chryseobacterium meningosepticum. During a 11-day period, the outbreak was observed among four newborns in a neonatal intensive care unit (NICU) in a teaching hospital. All patients yielded C. meningosepticum in their blood cultures, in addition one was colonised in the throat. Antimicrobial susceptibility assay showed complete resistance to penicillins, cephalosporins, aminoglycosides, imipenem, aztreonam, and tetracycline, sensitivity to ciprofloxacin and trimethoprim-sulfamethoxazole. All patients were empirically treated with amikacin and meropenem. The neonate who was the first to develop sepsis died before the culture result. When C. meningosepticum was identified, antimicrobial therapy was changed to a combination of ciprofloxacin, rifampicin and vancomycin, and three neonates were treated successfully. Environmental screening recovered C. meningosepticum from two venous catheter lines and one nutritional solution that was opened by health care staff and used for two neonates. Arbitrary primed polymerase chain reaction and antibiogram typing indicated that all isolates were epidemiologically related. This study demonstrates that rapid selection of appropriate antibiotics is critical for clinical cure and standard precautions should be reconsidered to limit the spread of this bacterium on the NICU in our hospital.  相似文献   
53.
The etiology of otitis media with effusion (OME) is unclear. The bacterial analyses of middle ear effusion (MEE) in OME may reveal important information regarding its etiology. Alloiococcus otitidis, Heamophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis were investigated by using microbiologic culture and a multiplex PCR method in the middle ear fluid of 32 children (54 samples) with chronic OME. PCR yielded positive results in 18 (33.3%) middle ear effusions while culture resulted positive for 3 (5.6%). The PCR method detected A. otitidis in 10 (18.5%) specimens, H. influenzae in 7 (13%), M. catarrhalis in 4 (7.4%) and S. pneumoniae in 2 (3.7%) specimens. The multiplex PCR method enhances the detection rate significantly compared to that of the conventional culture method. A. otitidis is the most common detected pathogen in the MEE of the OME.  相似文献   
54.
The interactions of biological macromolecules with nanoparticles underlie a wide variety of current and future applications in the fields of biotechnology, medicine and bioremediation. The same interactions are also responsible for mediating potential biohazards of nanomaterials. Some applications require that proteins adsorb to the nanomaterial and that the protein resists or undergoes structural rearrangements. This article presents a screening method for detecting nanoparticle-protein partners and conformational changes on time scales ranging from milliseconds to days. Mobile fluorophores are used as reporters to study the interaction between proteins and nanoparticles in a high-throughput manner in multi-well format. Furthermore, the screening method may reveal changes in colloidal stability of nanomaterials depending on the physicochemical conditions.  相似文献   
55.
Bacteriological and epidemiological studies were carried out on 90 isolates of methicillin-resistant Staphylococcus aureus (MRSA) at Turgut Ozal Medical Center of In?nü University, (Malatya/Turkey). MRSA isolates were obtained from patients with nosocomial infections. Staphylococcus aureus clinical isolates were collected between May 2004-May 2005. Isolates were tested for resistance to methicillin. Antimicrobial susceptibility testing and slime production evaluation was performed. Genotype studies were carried out by arbitrarily primed polymerase chain reaction (AP-PCR) and consequent cluster analysis. All of the isolates were mecA-positive in a PCR-based assay; all exhibited resistance to oxacillin, by agar dilution (MICs > or = 4 mg/L) and disc diffusion methods, and multiple antibiotics. Most MRSA isolates were collected in intensive care units. Of 90 samples, 53 were found to be unrelated to the others while the remaining 37 strains were either identical or closely related. Dendrogram analysis identified nine major clusters. These data support the opinion that MRSA are significant nosocomial pathogens in intensive care units and that resistant clones may be transmitted between patients. Molecular epidemiological tools are helpful for understanding transmission patterns and sources of infection, and are useful for measuring outcomes of intervention strategies implemented to reduce nosocomial MRSA.  相似文献   
56.
Hyperhomocysteinemia is associated with a lot of diseases including cardiovascular diseases and neural tube defect, but it has not been clarified exactly which mechanism is responsible for occurence disease. Here, homocysteine (Hcy) and cysteine (Cys), which are thiol containing amino acids, were examined for their effect on glutathione peroxidase (GPx) activity. It was observed that the GPx-1 activity was inhibited under severe hyperhomocysteinemia (50-500 microM Hcy) conditions, especially at low glutathione concentrations but that cysteine increased GPx-1 activity at low glutathione concentrations and inhibition clearly appeared at 500 microM Cys concentration.  相似文献   
57.
Biased population sex ratios can alter optimal male mating strategies, and allocation to reproductive traits depends on nutrient availability. However, there is little information on how nutrition interacts with sex ratio to influence the evolution of pre-copulatory and post-copulatory traits separately. To address this omission, we test how male mating success and reproductive investment evolve under varying sex ratios and adult diet in Drosophila melanogaster, using experimental evolution. We found that sex ratio and nutrient availability interacted to determine male pre-copulatory performance. Males from female-biased populations were slow to mate when they evolved under protein restriction. By contrast, we found direct and non-interacting effects of sex ratio and nutrient availability on post-copulatory success. Males that evolved under protein restriction were relatively poor at suppressing female remating. Males that evolved under equal sex ratios fathered more offspring and were better at supressing female remating, relative to males from male-biased or female-biased populations. These results support the idea that sex ratios and nutrition interact to determine the evolution of pre-copulatory mating traits, but independently influence the evolution of post-copulatory traits.  相似文献   
58.
Four proline-derived chiral receptors 5-8 were readily synthesized starting from L-proline. The enantiomeric recognition ability of chiral receptors was examined with a series of carboxylic acids by (1) H NMR spectroscopy. The molar ratio and the association constants of the chiral compounds with each of the enantiomers of guest molecules were determined by using Job plots and a nonlinear least-squares fitting method, respectively. The Job plots indicate that the hosts form 1:1 instantaneous complexes with all guests. The receptors exhibited different chiral recognition abilities toward the enantiomers of racemic guests. Among the chiral receptors used in this study, prolinamide 6 was found to be the best chiral shift reagent and is effective for the determination of the enantiomeric excess of chiral carboxylic acids.  相似文献   
59.
Human orf is a viral zoonotic infection caused by Parapoxvirus. The skin lesions of human orf can be misdiagnosed as cutaneous anthrax leading to overtreatment and also fear. This study was conducted to analyze an outbreak which led to deaths among kids and lambs in the same flock, and skin lesions in some persons who were living on the same farm that were initially diagnosed as cutaneous anthrax by a practitioner. Eight patients with skin lesions and eleven persons who had no skin lesion were considered as patients and control groups, respectively. The cultures obtained from the lesions of all patients were negative for Bacillus anthracis. The diagnosis of skin lesions was done by clinical findings, histopathological examination and PCR as human orf. To be under 20 years of age, direct contact with the animals, and contact with flayed skin of sick animals were the risk factors for human orf (Odds Ratio 7.5; 95% Confidence Interval 1.02-54.54, OR 12.25; 95% CI:1.3-100.9, OR 16.67; 95% CI:1.65-148.20, respectively). Orf should be kept in mind in the differential diagnosis of skin lesions resembling anthrax. For control and prevention of orf, transmission routes should be known; good hand hygiene and other personal protective measures have to be implemented.  相似文献   
60.
Boron is a necessary nutrient for plants and animals, however excess of it causes toxicity. Previously, Atr1 and Arabidopsis Bor1 homolog were identified as the boron efflux pump in yeast, which lower the cytosolic boron concentration and help cells to survive in the presence of toxic amount of boron. In this study, we analyzed ATR1 paralogs, YMR279c and YOR378w, to understand whether they participate in boron stress tolerance in yeast. Even though these genes share homology with ATR1, neither their deletion rendered cells boron sensitive nor their expression was significantly upregulated by boron treatment. However, expression of YMR279, but not YOR378w, from the constitutive GAPDH promoter on a high copy plasmid provided remarkable boron resistance by decreasing intracellular boron levels. Thus our results suggest the presence of a third boron exporter, YMR279c, which functions similar to ATR1 and provides boron resistance in yeast.  相似文献   
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