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851.
Fine-Scale Genetic Diversity among Burkholderia pseudomallei Soil Isolates in Northeast Thailand 下载免费PDF全文
Jana M. U'Ren Heidie Hornstra Talima Pearson James M. Schupp Benjamin Leadem Shalamar Georgia Rasana W. Sermswan Paul Keim 《Applied microbiology》2007,73(20):6678-6681
Burkholderia pseudomallei soil isolates from northeast Thailand were genotyped using multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA) and multilocus sequence typing (MLST). MLVA identified 19 genotypes within three clades, while MLST revealed two genotypes. These close genetic relationships imply a recent colonization followed by localized expansion, similar to what occurs in an outbreak situation. 相似文献
852.
Detection and delineation of squamous neoplasia with hyperspectral imaging in a mouse model of tongue carcinogenesis 下载免费PDF全文
Guolan Lu Dongsheng Wang Xulei Qin Susan Muller Xu Wang Amy Y. Chen Zhuo Georgia Chen Baowei Fei 《Journal of biophotonics》2018,11(3)
Hyperspectral imaging (HSI) holds the potential for the noninvasive detection of cancers. Oral cancers are often diagnosed at a late stage when treatment is less effective and the mortality and morbidity rates are high. Early detection of oral cancer is, therefore, crucial in order to improve the clinical outcomes. To investigate the potential of HSI as a noninvasive diagnostic tool, an animal study was designed to acquire hyperspectral images of in vivo and ex vivo mouse tongues from a chemically induced tongue carcinogenesis model. A variety of machine‐learning algorithms, including discriminant analysis, ensemble learning, and support vector machines, were evaluated for tongue neoplasia detection using HSI and were validated by the reconstructed pathological gold‐standard maps. The diagnostic performance of HSI, autofluorescence imaging, and fluorescence imaging were compared in this study. Color‐coded prediction maps were generated to display the predicted location and distribution of premalignant and malignant lesions. This study suggests that hyperspectral imaging combined with machine‐learning techniques can provide a noninvasive tool for the quantitative detection and delineation of squamous neoplasia. 相似文献
853.
Kenneth Blum Georgia M. Dunston David Baron Edward J. Modestino Thomas McLaughlin Bruce Steinberg Mark S. Gold Marjorie C. Gondré-Lewis 《Molecular neurobiology》2018,55(7):5526-5536
Alzheimer’s disease is an irreversible, progressive brain disorder that slowly destroys cognitive skills and the ability to perform the simplest tasks. More than 5 million Americans are afflicted with Alzheimer’s; a disorder which ranks third, just behind heart disease and cancer, as a cause of death for older people. With no real cure and in spite of enormous efforts worldwide, the disease remains a mystery in terms of treatment. Importantly, African-Americans are two times as likely as Whites to develop late-onset Alzheimer’s disease and less likely to receive timely diagnosis and treatment. Dopamine function is linked to normal cognition and memory and carriers of the DRD2 Taq1A A1 allele have significant loss of D2 receptor density in the brain. Recent research has shown that A1 carriers have worse memory performance during long-term memory (LTM) updating, compared to non-carriers or A2-carriers. A1carriers also show less blood oxygen level-dependent (BOLD) activation in the left caudate nucleus which is important for LTM updating. This latter effect was only seen in older adults, suggesting magnification of genetic effects on brain functioning in the elderly. Moreover, the frequency of the A1 allele is 0.40 in African-Americans, with an approximate prevalence of the DRD2 A1 allele in 50% of an African-American subset of individuals. This is higher than what is found in a non-screened American population (≤ 28%) for reward deficiency syndrome (RDS) behaviors. Based on DRD2 known genetic polymorphisms, we hypothesize that the DRD2 Taq1A A1 allele magnifies the risk of Alzheimer’s in aging African-Americans. Research linking this high risk for Alzheimer’s in the African-American population, with DRD2/ANKK1-TaqIA polymorphism and neurocognitive deficits related to LTM, could pave the way for novel, targeted pro-dopamine homeostatic treatment. 相似文献
854.
Charli Sargent Michele Lastella Georgia Romyn Nathan Versey Dean J. Miller Gregory D. Roach 《Chronobiology international》2018,35(6):754-758
ABSTRACTThe validity of a commercially available wearable device for measuring total sleep time was examined in a sample of well-trained young athletes during night-time sleep periods and daytime naps. Participants wore a FitBit HR Charge on their non-dominant wrist and had electrodes attached to their face and scalp to enable polysomnographic recordings of sleep in the laboratory. The FitBit automatically detected 24/30 night-time sleep periods but only 6/20 daytime naps. Compared with polysomnography, the FitBit overestimated total sleep time by an average of 52 ± 152 min for night-time sleep periods, and by 4 ± 8 min for daytime naps. It is important for athletes and practitioners to be aware of the limitations of wearable devices that automatically detect sleep duration. 相似文献
855.
George Kluck Karla C. Régis Nuccia N.T. De Cicco Lívia Silva-Cardoso Miria G. Pereira Patrícia Fampa Alessandra C. Chagas-Lima Alexandre Romeiro Narcisa L. Cunha-Silva Georgia C. Atella 《Parasitology international》2018,67(2):97-106
Lipid uptake and metabolism by trypanosomatid parasites from vertebrate host blood have been well established in the literature. However, there is a lack of knowledge regarding the same aspects concerning the parasites that cross the hemolymph of their invertebrate hosts. We have investigated the lipid composition and metabolism of the insect trypanosomatid Herpetomonas muscarum by 3H- palmitic acid and phosphate (32Pi) and the parasite interaction with Lipophorin (Lp) the main lipid carrying protein of insect hemolymph. Gas chromatography-mass spectrometry (GC–MS) analyses were used to identify the fatty acids and sterols composition of H.muscarum. Furthermore, we investigated the Lp binding site in the plasma membrane of parasite by Immunolocalization. We showed that H. muscarum incorporated 3H-palmitic acid and inorganic phosphate (32Pi) which were readily used as precursor molecules of lipid biosynthetic pathways. Furthermore, H. muscarum was able to take up both protein and lipid moieties of Lp which could be used as nutrient sources. Moreover, we have also demonstrated for the first time the presence of a Lp binding site in the membrane of a parasite. Such results point out the role of describing the metabolic pathways of trypanosomatids in order to provide a better understanding of parasite-host interaction peculiarities. Such studies may enhance the potential form the identification of novel chemotherapeutic targets in harmful parasites. 相似文献
856.
Georgia Thodi Kleopatra H. Schulpis Elina Molou Vassiliki Georgiou Yannis L. Loukas Yannis Dotsikas Konstantinos Papadopoulos Sofia Biti 《Gene》2013
Biotinidase deficiency (BTD) is an inherited disorder with severe clinical manifestations if not treated early. 63,119 neonates were tested for BTD according to a 3-step protocol. Biotinidase activity was initially estimated through standard colorimetric method on dried blood spots, then the suspected samples were subjected to molecular analysis of the BT gene and determination of BT activity in serum through an HPLC method. 14 infants with partial BTD (incidence 1:4508) were detected. Nine of them were homozygotes (D444H/D444H), and 4 compound heterozygotes carrying D444H combined with Q456H, T532M, C186Y and R157H, respectively. All were asymptomatic and supplemented with 10 mg biotin. Although the number of screened neonates is rather small, it may be suggested that the incidence of the partial BTD infants is the highest ever reported. Detection of BTD should be added to the Greek national neonatal screening program. 相似文献
857.
858.
Athanassios Molassiotis Georgia Tanou Panagiota Filippou Vasileios Fotopoulos 《Proteomics》2013,13(12-13):1871-1884
Fruit tree crops are agricultural commodities of high economic importance, while fruits also represent one of the most vital components of the human diet. Therefore, a great effort has been made to understand the molecular mechanisms covering fundamental biological processes in fruit tree physiology and fruit biology. Thanks to the development of cutting‐edge “omics” technologies such as proteomic analysis, scientists now have powerful tools to support traditional fruit tree research. Such proteomic analyses are establishing high‐density 2DE reference maps and peptide mass fingerprint databases that can lead fruit science into a new postgenomic research era. Here, an overview of the application of proteomics in key aspects of fruit tree physiology as well as in fruit biology, including defense responses to abiotic and biotic stress factors, is presented. Α panoramic view of ripening‐related proteins is also discussed, as an example of proteomic application in fruit science. 相似文献
859.
860.
MicroRNAs (miRNAs) and related polymorphisms have been implicated in the susceptibility to oesophageal squamous cell carcinoma (OSCC). In our study, three miRNA-related SNPs: rs6505162 A>C (pre-miRNA of miR-423), rs213210 A>G (3’UTR of miR-219-1) and rs7372209 C>T (5’UTR of miR-26a-1) were investigated in the Black and Mixed Ancestry population groups in South Africa. The potential cumulative effects of these SNPs, as well as gene-environment interactions were also analysed. In Blacks, rs6505162 A>C was associated with OSCC under dominant, additive and recessive models with odds ratios (ORs) 1.353, 1.404, and 2.858, respectively. This locus showed very strong interactions with smoke inhalation from burning wood or charcoal used for heating and cooking in very poorly ventilated areas (OR(GE)=7.855, P(GE)=9.17*10-10 in the Black group). Furthermore, the miR-423-3p level was 1.39 fold up-regulated in tumour tissues compared to the adjacent normal tissue (paired t-test P value 0.0087). SNP-SNP interaction between rs2132210 and rs7372209 was found in both Black and Mixed Ancestry subjects. The AArs213210-CTrs7372209 genotype had a protective effect on OSCC risk (in the Black, OR=0.229, P=0.012; and the Mixed Ancestry groups, OR=0.230, P=0.00014). This study is the first to link SNPs in miR-423 together with environmental smoke exposure to risk for developing OSCC. 相似文献