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51.
Electron paramagnetic resonance (EPR) spin-labeling methods were used to study the organization of cholesterol and phospholipids in membranes formed from Chol/POPS (cholesterol/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylserine) mixtures, with mixing ratios from 0 to 3. It was confirmed using the discrimination by oxygen transport and polar relaxation agent accessibility methods that the immiscible cholesterol bilayer domain (CBD) was present in all of the suspensions when the mixing ratio exceeded the cholesterol solubility threshold (CST) in the POPS membrane. The behavior of phospholipid molecules was monitored with phospholipid analogue spin labels (n-PCs), and the behavior of cholesterol was monitored with the cholesterol analogue spin labels CSL and ASL. Results indicated that phospholipid and cholesterol mixtures can form a membrane suspension up to a mixing ratio of ~2. Additionally, EPR spectra for n-PC, ASL, and CSL indicated that both phospholipids and cholesterol exist in these suspensions in the lipid-bilayer-like structures. EPR spectral characteristics of n-PCs (spin labels located in the phospholipid cholesterol bilayer, outside the CBD) change with increase in the cholesterol content up to and beyond the CST. These results present strong evidence that the CBD forms an integral part of the phospholipid bilayer when formed from a Chol/POPS mixture up to a mixing ratio of ~2. Interestingly, CSL in cholesterol alone (without phospholipids) when suspended in buffer does not detect formation of bilayer-like structures. A broad, single-line EPR signal is given, similar to that obtained for the dry film of cholesterol before addition of the buffer. This broad, single-line signal is also observed in suspensions formed for Chol/POPS mixtures (as a background signal) when the Chol/POPS ratio is much greater than 3. It is suggested that the EPR spin-labeling approach can discriminate and characterize the fraction of cholesterol that forms the CBD within the phospholipid bilayer. 相似文献
52.
The efficiency of protected areas (PAs) has often been questioned due to global decline of biodiversity. Invertebrates, especially insects, have been historically underrepresented in conservation studies. Our study focuses on hoverflies, an important group of insect pollinators and proven to be good bioindicators. Research was focused in Serbia, one of Europe's hotspots of hoverfly diversity, with a long tradition of hoverfly research, which provided sufficient information for achieving our aims: identifying areas of high hoverfly diversity, evaluating the efficiency of PAs and prime hoverfly areas (PHAs) in the conservation of hoverflies, determining how well they cover the distribution of hoverfly species, especially those of conservation concern, and testing the importance of the size of the area for conservation of hoverfly diversity. We applied weighting of the species to help stress the importance of species of conservation concern. The results indicated that PHAs cover the areas with high hoverfly diversity better than PA networks, especially when it comes to species of conservation concern. Generalized linear model results showed that the area size was a significant predictor of number of species in both PA and PHA. This indicates that area size is key when designating new areas important for conservation, but there are also other factors that need to be taken into account, such as habitat quality or suitability. Studies like this are useful in aiding designation of new areas important for conservation of certain species and in identifying sampling gaps, which could potentially aim future research in that direction. 相似文献
53.
BackgroundWe sought to determine the clinical outcomes of patients with breast cancer (BC) who had undergone stereotactic radiosurgery (SRS) for a limited number of brain metastases (BM) and to identify factors influencing overall survival (OS) and local control.Materials and methodsThe records of 45 patients who underwent SRS for 72 brain lesions were retrospectively evaluated. Statistics included the chi-squared test, Kaplan-Meier method, and the multivariate Cox model.ResultsThe median number of treated BM was 2 (range 1–10). Median OS from BM diagnosis and post-SRS were 27.6 [95% confidence interval (CI): 14.8–40.5) and 18.5 months (95% CI: 11.1–25.8), respectively. One-year and two-year survival rates after BM diagnosis were 55% and 41%, respectively. In a univariate analysis, the Luminal-B-human-epidermal-growth-receptor-positive (HER2+) subtype had the longest median OS at 39.1 months (95% CI: 34.1–44.1, p = 0.004). In an adjusted analysis, grade 2 [hazard ratio (HR): 0.1; 95% CI: 0.1–0.6, p = 0.005), craniotomy (HR: 0.3; 95% CI: 0.1–0.7; p = 0.006), and ≥ 2 systemic therapies received (HR: 0.3; 95% CI: 0.1–0.9, p = 0.028) were associated with improved OS. One-year and two-year intracranial progression-free survival rates were 85% and 63%, respectively. Four factors for a higher risk of any intracranial recurrence remained significant in the adjusted analysis, as follows: age < 50 years (HR: 4.2; 95% CI: 1.3–36.3; p = 0.014), grade 3 (HR: 3.7; 95% CI: 1.1–13.2; p = 0.038), HER2+ (HR: 6.9; 95% CI: 1.3–36.3; p = 0.023), and whether the brain was the first metastatic site (HR: 4.7; 95% CI: 1.6–14.5; p = 0.006).ConclusionIntrinsic BC characteristics are important determinants for both survival and intracranial control for patients undergoing SRS for oligometastatic brain disease. 相似文献
54.
Predrag Noveski Svetlana Madjunkova Marija Mircevska Toso Plaseski Vanja Filipovski Dijana Plaseska-Karanfilska 《PloS one》2014,9(11)
Congenital bilateral absence of vas deferens (CBAVD) is the most common CFTR-related disorder (CFTR-RD) that explains about 1–2% of the male infertility cases. Controversial data have been published regarding the involvement of CFTR mutations in infertile men with non-obstructive azoospermia and oligozoospermia. Here, we describe single base extension (SNaPshot) assay for detection of 11 common CFTR mutations: F508del, G542X, N1303K, 621+1G->T, G551D, R553X, R1162X, W1282X, R117H, 2184insA and 1717-1G->A and IVS8polyT variants. The assay was validated on 50 previously genotyped samples and was used to screen a total of 369 infertile men with different impairment of spermatogenesis and 136 fertile controls. Our results show that double heterozygosity of cystic fibrosis (CF) and CFTR-related disorder (CFTR-RD) mutations are found in a high percentage (22.7%) of infertile men with obstructive azoospermia, but not in other studied groups of infertile men. The SNaPshot assay described here is an inexpensive, fast and robust method for primary screening of the most common CFTR mutations both in patients with classical CF and CFTR-RD. It can contribute to better understanding of the role of CFTR mutations in impaired spermatogenesis, ultimately leading to improved management of infertile men. 相似文献
55.
Afrouz Behboudi Leyla Roshani Marija Kost-Alimova Eleonor Sjöstrand Kerstin Montelius-Alatalo Dan Röhme Karin Klinga-Levan Fredrik Ståhl 《Mammalian genome》2002,13(6):302-309
The rat provides valuable and sometimes unique models of human complex diseases. To fully exploit the rat models in biomedical
research, it is important to have access to detailed knowledge of the rat genome organization as well as its relation to the
human genome. Rat Chromosome 10 (RNO10) harbors several important cancer-related genes. Deletions in the proximal part of
RNO10 were repeatedly found in a rat model for endometrial cancer. To identify functional and positional candidate genes in
the affected region, we used radiation hybrid (RH) mapping and single- and dual-color fluorescence in situ hybridization (FISH)
techniques to construct a detailed chromosomal map of the proximal part of RNO10. The regional localization of 14 genes, most
of them cancer-related (Grin2a, Gspt1, Crebbp, Gfer, Tsc2, Tpsb1, Il9r, Il4, Irf1, Csf2, Sparc, Tp53, Thra1, Gh1), and of five microsatellite markers (D10Mit10, D10Rat42, D10Rat50, D10Rat72, and D10Rat165) was determined on RNO10. For a fifteenth gene, Ppm1b, which had previously been assigned to RNO10, the map position was corrected to RNO6q12-q13. 相似文献
56.
Pajtler M Audy-Jurković S Ovanin-Rakić A Makarović Z Milojković M Ljubojević N 《Collegium antropologicum》2003,27(1):239-246
The main objective of work was to determine a diagnostic value of cytology and colposcopy as a method of screening and differential diagnosis, as well as to determine the relative value of some colposcopic features of squamous and glandular cervical intraepithelial lesions. Cytological diagnosis and colposcopy findings is compared with histological ones for 187 patients with intraepithelial lesions (142 squamous and 45 glandular ones with or without squamous components) and determined the sensitivity and positive predictive value of cytology and colposcopy, including the types of colposcopic abnormalities associated with squamous/glandular intraepithelial lesions. The sensitivity of cytology as a screening method for SIL (squamous intraepithelial lesions) is 89% and for GIL (glandular intraepithelial lesions) 98%. Positive predictive value of differential cytology for SIL is 59% and for GIL 53%. Sensitivity of colposcopy for both lesions' type is 87%. Acetowhite epithelium occurs for more often with SIL, whereas atypical vessels and unequal, dilated gland openings with GIL (p < 0.05). Cytology and colposcopy as screening methods have a high sensitivity. Nevertheless, cytology is far more accurate in determining differential diagnosis of SIL than GIL and some colposcopy abnormalities suspicious of GIL should be further tested in praxis. 相似文献
57.
Schiavinato A Becker AK Zanetti M Corallo D Milanetto M Bizzotto D Bressan G Guljelmovic M Paulsson M Wagener R Braghetta P Bonaldo P 《The Journal of biological chemistry》2012,287(14):11498-11515
EMILIN-3 is a glycoprotein of the extracellular matrix belonging to a family that contains a characteristic N-terminal cysteine-rich EMI domain. Currently, EMILIN-3 is the least characterized member of the elastin microfibril interface-located protein (EMILIN)/Multimerin family. Using RNA, immunohistochemical, and protein chemistry approaches, we carried out a detailed characterization of the expression and biochemical properties of EMILIN-3 in mouse. During embryonic and postnatal development, EMILIN-3 showed a peculiar and dynamic pattern of gene expression and protein distribution. EMILIN-3 mRNA was first detected at E8.5-E9.5 in the tail bud and in the primitive gut, and at later stages it became abundant in the developing gonads and osteogenic mesenchyme. Interestingly and in contrast to other EMILIN/Multimerin genes, EMILIN-3 was not found in the cardiovascular system. Despite the absence of the globular C1q domain, immunoprecipitation and Western blot analyses demonstrated that EMILIN-3 forms disulfide-bonded homotrimers and higher order oligomers. Circular dichroism spectroscopy indicated that the most C-terminal part of EMILIN-3 has a substantial α-helical content and forms coiled coil structures involved in EMILIN-3 homo-oligomerization. Transfection experiments with recombinant constructs showed that the EMI domain contributes to the higher order self-assembly but was dispensable for homotrimer formation. EMILIN-3 was found to bind heparin with high affinity, a property mediated by the EMI domain, thus revealing a new function for this domain that may contribute to the interaction of EMILIN-3 with other extracellular matrix and/or cell surface molecules. Finally, in vitro experiments showed that EMILIN-3 is able to function as an extracellular regulator of the activity of TGF-β ligands. 相似文献
58.
Marija Brgles Pero Prebeg Tihana Kurtović Jelena Ranić Martina Marchetti-Deschmann Günter Allmaier 《Preparative biochemistry & biotechnology》2016,46(7):695-703
Tetanus toxoid (TTd) is a highly immunogenic, detoxified form of tetanus toxin, a causative agent of tetanus disease, produced by Clostridium tetani. Since tetanus disease cannot be eradicated but is easily prevented by vaccination, the need for the tetanus vaccine is permanent. The aim of this work was to investigate the possibility of optimizing TTd purification, i.e., ammonium sulfate precipitation process. The influence of the percentage of ammonium sulfate, starting amount of TTd, buffer type, pH, temperature, and starting purity of TTd on the purification process were investigated using optimal design for response surface models. Responses measured for evaluation of the ammonium sulfate precipitation process were TTd amount (Lf/mL) and total protein content. These two parameters were used to calculate purity (Lf/mgPN) and the yield of the process. Results indicate that citrate buffer, lower temperature, and lower starting amount of TTd result in higher purities of precipitates. Gel electrophoresis combined with matrix-assisted laser desorption ionization–mass spectrometric analysis of precipitates revealed that there are no inter-protein cross-links and that all contaminating proteins have pIs similar to TTd, so this is most probably the reason for the limited success of purification by precipitation. 相似文献
59.
Ebling B Kovacić L Ebling Z Vlahusić A Tokalić M Glavina K Serić V Strnad M Bilić A Santo T Samija M Jurcić D 《Collegium antropologicum》2005,29(1):169-178
Cancer morbidity and mortality are on a steady increase in Croatia. Technologic possibilities for appropriate management are available for four cancer sites, i.e. cancer of the breast, cervix uteri, colorectum and prostate, and include cancer prevention and early detection in individuals yet free from manifest signs of the disease. The magnitude of the problem, the experience acquired to date, health care personnel available, and additional resources required to launch a systematic program of early detection of the disease are presented. The program should be initially launched in a county with greatest experience in early detection of cancer, where health care service is ready to immediately start its implementation. The role of family physician, gynecologic service at primary health care level, and polyclinic-consultation hospital service in program implementation is described. The following three possible options for early detection of cancer are analyzed and proposed: minimal program (early detection every 3 years), medium program (the same individuals examined every 2 years), and optimal program proposed by the American Cancer Society and other national and international organizations. 相似文献
60.
Stankovic M Nikolic A Divac A Tomovic A Petrovic-Stanojevic N Andjelic M Dopudja-Pantic V Surlan M Vujicic I Ponomarev D Mitic-Milikic M Kusic J Radojkovic D 《Genetic testing》2008,12(3):357-362
Chronic obstructive pulmonary disease (COPD) is a complex disease influenced by genetic and environmental factors. Cystic fibrosis transmembrane conductance regulator (CFTR) protein is an important component of the lung tissue homeostasis, involved in the regulation of the rate of mucociliary clearance. As it is known that certain CFTR variants have consequences on the function of CFTR protein, the aim of this study was to examine the possible role of F508del, M470V, Tn locus, and R75Q variants in COPD development and modulation. Total number of 86 COPD patients and 102 control subjects were included in the study. Possible association between COPD susceptibility, severity, and onset of the disease and allele or genotype of four analyzed CFTR variants was examined. No associations were detected between COPD development, onset of the disease and tested CFTR alleles and genotypes. However, VV470 genotype was associated with mild/moderate COPD stages in comparison to severe/very severe ones (OR = 0.29, 95%CI = 0.11-0.80, p = 0.016). Our study showed that patients with VV470 genotype had a 3.4-fold decreased risk for the appearance of severe/very severe COPD symptoms, and the obtained results indicate that this genotype may have a protective role. These results also suggest the importance of studying CFTR gene as a modifier of this disease. 相似文献