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71.
The infection with Human papillomavirus (HPV) is the necessary cause for cervical cancer. There are at least 15 High-Risk (HR) HPV types that are significantly associated with progression of cervical intraepithelial neoplasia to cervical cancer. Since previous studies showed that the prevalence of HPV in cervical cancers varies among different geographic regions, we wanted to investigate the prevalence of HPV types in Croatia, especially low abundant HR HPV types. By means of consensus primers directed polymerase chain reaction (PCR), we analysed cervical DNA samples of 2,136 Croatian women, mostly with abnormal cervical smears, in order to detect the presence of HPV Type-specific primers were then used to determine Low-Risk (LR) HPV types 6/11 and HR HPV types 16, 18, 31, 33, 45, 52 and 58. Out of 2,136 specimens, 1,255 (58.8%) were positive for HPV More than half of positive samples were typed (64.5%) and 35.5% still remained untyped. Multiple HPV infections were found in 10.3% of the cases. The most prevalent type, including both single and multiple infections, was HPV16 with the prevalence of 15.9%, followed by HPV types 31, 6/11, 33, 18, 52, 45 and 58 with 8.7%, 7.1%, 4.5%, 3.8%, 2.3%, 1.2% and 1.1%, respectively. The significant increase of frequency from Low-grade Squamous Intraepithelial Lesions (LSIL) to High-grade Squamous Intraepithelial Lesions (HSIL) was observed for HR HPV types 16, 18, 31 and 33 but not 45, 52 and 58. The frequency of unknown HPV types was almost the same in cervical specimens of women with LSIL and those with HSIL, 19.8% and 21.1%, respectively. The prevalence of HPV infection rate decreased significantly with patient age from 68.5% (age group 12 to 24 years) to 38.8% (age group 45 to 54 years). But, in women aged 55 or older the overall prevalence increased to 56.6%. Our results indicate that prevalence of HR HPV types in Croatia is similar to other countries. We suggest that HPV positive women in Croatia should be closely monitored by typing for HR HPV types: 16, 18, 31, 33, 45, 52 and 58. 相似文献
72.
Kariz S Milutinović A Bregar D Terzić I Terzić R Lovrecić L Herova M Hruskovicova H Peterlin B Petrovic D Zorc-Pleskovic R 《Collegium antropologicum》2007,31(2):503-507
In this study we investigated the association of the interleukin-1 receptor antagonist gene variable number tandem repeat (IL1RN VNTR) polymorphism and of the inhibitor of kappa B-like protein (IKBL) gene polymorphism with myocardial infarction (MI) in a group of patients with type 2 diabetes. The IL1RN VNTR and the IKBL+ 738T > C gene polymorphisms were tested in 374 Caucasians: 151 cases with MI and 223 subjects with no history of coronary artery disease. The IL1RN VNTR polymorphism was not a risk factor for MI in Caucasians with type 2 diabetes (genotype 22 vs. the rest: odds ratio (OR) 1.6; 95% confidence interval (CI) = 0.8-3.5; p = 0.2). We also failed to demonstrate that IKBL+ 738T > C gene polymorphism was associated with MI in patients with type 2 diabetes (OR = 0.9; 95% CI = 0.3-2.6; p = 0.9). We provide evidence that the IL1RN VNTR and the IKBL + 738T > C gene polymorphisms are not risk factors for MI in Caucasians with type 2 diabetes. 相似文献
73.
74.
Pietkiewicz J Gamian A Staniszewska M Danielewicz R 《Journal of enzyme inhibition and medicinal chemistry》2009,24(2):356-364
Methylglyoxal (MG) was studied as an inhibitor and effective glycating factor of human muscle-specific enolase. The inhibition was carried out by the use of a preincubation procedure in the absence of substrate. Experiments were performed in anionic and cationic buffers and showed that inhibition of enolase by methylglyoxal and formation of enolase-derived glycation products arose more effectively in slight alkaline conditions and in the presence of inorganic phosphate. Incubation of 15 micromolar solutions of the enzyme with 2 mM, 3.1 mM and 4.34 mM MG in 100 mM phosphate buffer pH 7.4 for 3 h caused the loss a 32%, 55% and 82% of initial specific activity, respectively. The effect of MG on catalytic properties of enolase was investigated. The enzyme changed the K(M) value for glycolytic substrate 2-phospho-D-glycerate (2-PGA) from 0.2 mM for native enzyme to 0.66 mM in the presence of MG. The affinity of enolase for gluconeogenic substrate phosphoenolpyruvate altered after preincubation with MG in the same manner, but less intensively. MG has no effect on V(max) and optimal pH values. Incubation of enolase with MG for 0-48 h generated high molecular weight protein derivatives. Advanced glycation end products (AGEs) were resistant to proteolytic degradation by trypsin. Magnesium ions enhanced the enzyme inactivation by MG and facilitated AGEs formation. However, the protection for this inhibition in the presence of 2-PGA as glycolytic substrate was observed and AGEs were less effectively formed under these conditions. 相似文献
75.
Anderson IJ Sieprawska-Lupa M Lapidus A Nolan M Copeland A Glavina Del Rio T Tice H Dalin E Barry K Saunders E Han C Brettin T Detter JC Bruce D Mikhailova N Pitluck S Hauser L Land M Lucas S Richardson P Whitman WB Kyrpides NC 《Standards in genomic sciences》2009,1(2):189-196
Methanoculleus marisnigri Romesser et al. 1981 is a methanogen belonging to the order Methanomicrobiales within the archaeal phylum Euryarchaeota. The type strain, JR1, was isolated from anoxic sediments of the Black Sea. M. marisnigri is of phylogenetic interest because at the time the sequencing project began only one genome had previously been sequenced from the order Methanomicrobiales. We report here the complete genome sequence of M. marisnigri type strain JR1 and its annotation. This is part of a Joint Genome Institute 2006 Community Sequencing Program to sequence genomes of diverse Archaea. 相似文献
76.
Interactions between the endoplasmic reticulum, mitochondria, plasma membrane and other subcellular organelles 总被引:1,自引:0,他引:1
Magdalena Lebiedzinska Gyrgy Szabadkai Aleck W.E. Jones Jerzy Duszynski Mariusz R. Wieckowski 《The international journal of biochemistry & cell biology》2009,41(10):1805-1816
Several recent works show structurally and functionally dynamic contacts between mitochondria, the plasma membrane, the endoplasmic reticulum, and other subcellular organelles. Many cellular processes require proper cooperation between the plasma membrane, the nucleus and subcellular vesicular/tubular networks such as mitochondria and the endoplasmic reticulum. It has been suggested that such contacts are crucial for the synthesis and intracellular transport of phospholipids as well as for intracellular Ca2+ homeostasis, controlling fundamental processes like motility and contraction, secretion, cell growth, proliferation and apoptosis. Close contacts between smooth sub-domains of the endoplasmic reticulum and mitochondria have been shown to be required also for maintaining mitochondrial structure. The overall distance between the associating organelle membranes as quantified by electron microscopy is small enough to allow contact formation by proteins present on their surfaces, allowing and regulating their interactions. In this review we give a historical overview of studies on organelle interactions, and summarize the present knowledge and hypotheses concerning their regulation and (patho)physiological consequences. 相似文献
77.
78.
Rossi AG Sawatzky DA Walker A Ward C Sheldrake TA Riley NA Caldicott A Martinez-Losa M Walker TR Duffin R Gray M Crescenzi E Martin MC Brady HJ Savill JS Dransfield I Haslett C 《Nature medicine》2006,12(9):1056-1064
Apoptosis is essential for clearance of potentially injurious inflammatory cells and subsequent efficient resolution of inflammation. Here we report that human neutrophils contain functionally active cyclin-dependent kinases (CDKs), and that structurally diverse CDK inhibitors induce caspase-dependent apoptosis and override powerful anti-apoptosis signals from survival factors such as granulocyte-macrophage colony-stimulating factor (GM-CSF). We show that the CDK inhibitor R-roscovitine (Seliciclib or CYC202) markedly enhances resolution of established neutrophil-dependent inflammation in carrageenan-elicited acute pleurisy, bleomycin-induced lung injury, and passively induced arthritis in mice. In the pleurisy model, the caspase inhibitor zVAD-fmk prevents R-roscovitine-enhanced resolution of inflammation, indicating that this CDK inhibitor augments inflammatory cell apoptosis. We also provide evidence that R-roscovitine promotes apoptosis by reducing concentrations of the anti-apoptotic protein Mcl-1. Thus, CDK inhibitors enhance the resolution of established inflammation by promoting apoptosis of inflammatory cells, thereby demonstrating a hitherto unrecognized potential for the treatment of inflammatory disorders. 相似文献
79.
Weidner Stanisław Każarnowicz Marta Frączek Ewa Amarowicz Ryszard Karamać Magdalena 《Acta Physiologiae Plantarum》2006,28(6):627-634
Some posttranslational processes that occur in embryos of germinating triticale caryopses treated with different concentrations
of abscisic acid (ABA) were examined. ABA increased the ratio of cytoskeleton-bound polysomes in the total population of polysomes
and depressed the share of free and membrane-bound polysomes. Using exogenous RNase, stability of the total polysomal population
as well as each polysomal fraction was investigated. The total extractable polysomes isolated from embryonic tissues of germinating
triticale caryopses treated with ABA were more stable than the polysomes isolated from the control sample caryopses. The contribution
of the polysomes that were not digested by RNase was increased by higher concentrations of ABA applied during germination.
At high concentrations of ABA (50, 100 μM), the quantitative contribution of polysomes in the total ribosomal fraction was
almost 100% of the amount of polysomes before digestion and the modifications observed consisted mainly of the shift of the
so-called heavy polysomes towards light polysomes, containing a few ribosomes. Within each polysomal population, cytoskeleton-bound
polysomes (CBP and CMBP) were the most stable, which may imply that the bonds between polysomes and these protein filaments,
created in all eukaryotic cells increased their stability. It is assumed that mRNAs are stabilised or destabilised by interaction
of proteins with their various sequences. A plant hormone may depress or elevate the quantities of these proteins, thus regulating
the stability of different mRNAs. The results confirm the multi-faceted mechanism of ABA-induced response, where one of the
constituents is the effect of ABA on the stability of mRNAs molecules. The co-ordinated regulation of mRNAs synthesis and
their stability provide plants with improved adaptability. 相似文献
80.
Wojciech Roczniak Barbara Brodziak-Dopierała Elżbieta Cipora Agata Jakóbik-Kolon Joanna Kluczka Magdalena Babuśka-Roczniak 《Biological trace element research》2017,178(2):201-209
Osteoarthritis causes the degradation of the articular cartilage and periarticular bones. Trace elements influence the growth, development and condition of the bone tissue. Changes to the mineral composition of the bone tissue can cause degenerative changes and fractures. The aim of the research was to determine the content of cadmium (Cd), nickel (Ni), copper (Cu) and zinc (Zn) in the tibia, the femur and the meniscus in men and women who underwent a knee replacement surgery. Samples were collected from 50 patients, including 36 women and 14 men. The determination of trace elements content were performed by ICP-AES method, using Varian 710-ES. Average concentration in the tissues of the knee joint teeth amounted for cadmium 0.015, nickel 0.60, copper 0.89 and zinc 80.81 mg/kg wet weight. There were statistically significant differences in the content of cadmium, copper and zinc in different parts of the knee joint. There were no statistically significant differences in the content of cadmium, nickel, copper and zinc in women and men in the examined parts of the knee joint. Among the elements tested, copper and nickel showed a high content in the connective tissue (the meniscus) compared to the bone tissue (the tibia and the femur). 相似文献