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21.
Maia A. Rabaa Chonticha Klungthong In-Kyu Yoon Edward C. Holmes Piyawan Chinnawirotpisan Butsaya Thaisomboonsuk Anon Srikiatkhachorn Alan L. Rothman Darunee Tannitisupawong Jared Aldstadt Ananda Nisalak Mammen P. Mammen Robert V. Gibbons Timothy P. Endy Thanyalak Fansiri Thomas W. Scott Richard G. Jarman 《PLoS neglected tropical diseases》2013,7(1)
Revealing the patterns and determinants of the spread of dengue virus (DENV) at local scales is central to understanding the epidemiology and evolution of this major human pathogen. We performed a phylogenetic analysis of the envelope (E) genes of DENV-1, -2, -3, and -4 isolates (involving 97, 23, 5, and 74 newly collected sequences, respectively) sampled from school-based cohort and village-based cluster studies in Kamphaeng Phet, Thailand, between 2004 and 2007. With these data, we sought to describe the spatial and temporal patterns of DENV spread within a rural population where a future vaccine efficacy trial is planned. Our analysis revealed considerable genetic diversity within the study population, with multiple lineages within each serotype circulating for various lengths of time during the study period. These results suggest that DENV is frequently introduced into both semi-urban and rural areas in Kamphaeng Phet from other populations. In contrast, the persistence of viral lineages across sampling years was observed less frequently. Analysis of phylogenetic clustering indicated that DENV transmission was highly spatially and temporally focal, and that it occurred in homes rather than at school. Overall, the strength of temporal clustering suggests that seasonal bottlenecks in local DENV populations facilitate the invasion and establishment of viruses from outside of the study area, in turn reducing the extent of lineage persistence. 相似文献
22.
Xiangdan Wang Valerie Quarmby Carl Ng Anan Chuntharapai Theresa Shek Charles Eigenbrot Robert F. Kelley Steven Shia Krista M McCutcheon John Lowe Cecilia Leddy Kyle Coachman Gary Cain Felix Chu Isidro Hotzel Mauricio Maia Eric Wakshull Jihong Yang 《MABS-AUSTIN》2013,5(4):540-554
Pharmacokinetic (PK) and immunohistochemistry (IHC) assays are essential to the evaluation of the safety and efficacy of therapeutic monoclonal antibodies (mAb) during drug development. These methods require reagents with a high degree of specificity because low concentrations of therapeutic antibody need to be detected in samples containing high concentrations of endogenous human immunoglobulins. Current assay reagent generation practices are labor-intensive and time-consuming. Moreover, these practices are molecule-specific and so only support one assay for one program at a time. Here, we describe a strategy to generate a unique assay reagent, 10C4, that preferentially recognizes a panel of recombinant human mAbs over endogenous human immunoglobulins. This “panel-specific” feature enables the reagent to be used in PK and IHC assays for multiple structurally-related therapeutic mAbs. Characterization revealed that the 10C4 epitope is conformational, extensive and mainly composed of non-CDR residues. Most key contact residues were conserved among structurally-related therapeutic mAbs, but the combination of these residues exists at low prevalence in endogenous human immunoglobulins. Interestingly, an indirect contact residue on the heavy chain of the therapeutic appears to play a critical role in determining whether or not it can bind to 10C4, but has no affect on target binding. This may allow us to improve the binding of therapeutic mAbs to 10C4 for assay development in the future. Here, for the first time, we present a strategy to develop a panel-specific reagent that can expedite the development of multiple clinical assays for structurally-related therapeutic mAbs. 相似文献
23.
Central giant cell lesion of the jaws: study of CCND1 gene amplification and p16INK4a protein levels
Renato Luiz Maia Nogueira Mário Henrique Girão Faria Rafael Lima Verde Osterne Roberta Barroso Cavalcante Ronaldo Albuquerque Ribeiro Cassiano Francisco Weege Nonaka Silvia Helena Barem Rabenhorst 《Journal of molecular histology》2013,44(5):527-534
Central giant cell lesions (CGCLs) are uncommon benign jaw lesions with uncertain etiology and a variable clinical behavior. In neoplasms, alterations in molecules involved in the G1/S checkpoint are frequently found. Loss of p16INK4a expression or overexpression of cyclin D1 may stimulate cell proliferation. The purpose of this study was to analyze CCND1 gene amplification and the expression of p16INK4a in CGCLs. Structural analysis of the CCND1 was performed using chromogenic in situ hybridization. Immmunohistochemistry was used to identify p16INK4a protein levels. Statistical analysis correlated the two biomarkers with clinical behavior and between each other. Twenty-four lesions were included, being 11 aggressive and 13 non-aggressive. Moderate/high-level CCND1 amplification was found in 12 lesions. Also, immunoreactivity for p16INK4a was present in 12 cases, mainly in mononuclear cells. There was a significantly higher level of p16INK4a expression in mononuclear cells of non-aggressive lesions and lesions with moderate/high-level CCND1 amplification in mononuclear cells. It could be speculated that some CGCLs may develop as a true benign neoplasm. The higher expression of p16INK4a in non-aggressive lesions and in cases with moderate/high-level CCND1 amplification may show that these molecules have a role in CGCLs. 相似文献
24.
Leandro Nolé Eduardo Michael Maia Mincarone Flávia Lucena-Frédou Júlia Rodrigues Martins Gabriel Vinícius Felix Afonso Bárbara Teixeira Villarins Thierry Frédou Alex Souza Lira Arnaud Bertrand 《Zeitschrift fur angewandte Ichthyologie》2020,36(6):845-848
Length-weight relationship parameters were calculated for twelve mesopelagic fish species from the western Tropical Atlantic: Diretmus argenteus, Melamphaes polylepis, Bolinichthys distofax, Diaphus lucidus, Diaphus splendidus, Electrona risso, Hygophum taaningi, Taaningichthys bathyphilus, Melanolagus bericoides, Winteria telescopa, Diplophos taenia, Astronesthes similus. Data was collected off northeastern Brazil from April 9th to May 6th, 2017. Hauls were conducted during day and night at 47 stations by using a micronekton trawl (body mesh: 40 mm, cod-end mesh: 10 mm) from 10 to 1,113 m depth. The material was fixed in a 4% formalin solution for 1 month and then preserved in a 70% alcohol solution for proximally 6 months before processing for length (nearest 0.1 cm of standard length) and weight (nearest 0.01 g of total weight). A new maximum standard length for Winteria telescopa is also provided. 相似文献
25.
Chad M. Eliason Rafael Maia Juan L. Parra Matthew D. Shawkey 《Evolution; international journal of organic evolution》2020,74(2):447-458
Understanding how animal signals are produced is critical for understanding their evolution because complexity and modularity in the underlying morphology can affect evolutionary patterns. Hummingbird feathers show some of the brightest and most iridescent colors in nature. These are produced by optically complex stacks of hollow, platelet-shaped organelles called melanosomes. Neither how these morphologies produce colors nor their evolution has been systematically studied. We first used nanoscale morphological measurements and optical modeling to identify the physical basis of color production in 34 hummingbird species. We found that, in general, the melanosome stacks function as multilayer reflectors, with platelet thickness and air space size explaining variation in hue (color) and saturation (color purity). Additionally, light rays reflected from the outer keratin surface interact with those reflected by small, superficial melanosomes to cause secondary reflectance peaks, primarily in short (blue) wavelengths. We then compared variation of both the morphological components and the colors they produce. The outer keratin cortex evolves independently and is more variable than other morphological traits, possibly due to functional constraints on melanosome packing. Intriguingly, shorter wavelength colors evolve faster than longer wavelength colors, perhaps due to developmental processes that enables greater lability of the shapes of small melanosomes. Together, these data indicate that increased structural complexity of feather tissues is associated with greater variation in morphology and iridescent coloration. 相似文献
26.
Revaz Solomonia Nana Gogichaishvili Maia Nozadze Eka Lepsveridze David Dzneladze Tamar Kiguradze 《Cellular and molecular neurobiology》2013,33(1):119-127
Identification of compounds preventing the biochemical changes that underlie the epileptogenesis process is of great importance. We have previously shown that myo-Inositol (MI) daily treatment prevents certain biochemical changes that are triggered by kainic acid (KA)-induced status epilepticus (SE). The aim of the current work was to study the further influence of MI treatment on the biochemical changes of epileptogenesis and focus on changes in the hippocampus and neocortex of rats for the following GABA-A receptor subunits: α1, α4, γ2, and δ. After SE, one group of rats was treated with saline, while the second group was treated with MI. Control groups that were not treated by the convulsant received either saline or MI administration. 28–30 h after the experiment, a decrease in the amount of the α1 subunit was revealed in the hippocampus and MI had no significant influence on it. On the 28th day of the experiment, the amount of α1 was increased in both the KA? and KA + MI-treated groups. The α4 and γ2 subunits were strongly reduced in the hippocampus of KA-treated animals, but MI significantly halted this reduction. The effects of MI on α4 and γ2 subunit changes were significantly different between hippocampus and neocortex. On the twenty-eighth day after SE, a decrease in the amount of α1 was found in the neocortex, but MI treatment had no effect on it. The obtained results indicate that MI treatment interferes with some of the biochemical processes of epileptogenesis. 相似文献
27.
Rachel S. N. de Pinho Francisco P. da Silva‐Júnior João Paulo C. Bastos Werllen S. Maia Marco Túlio de Mello Veralice M. S. de Bruin 《Chronobiology international》2013,30(5):963-971
Truck drivers are more likely to suffer severe injury and death due to certain truck driving characteristics. Identifying and preventing factors associated with accidents in this population is important to minimize damage and improve road safety. Excessive daytime sleepiness is a major public health problem, leading to impaired cognitive function, reduced alertness, and increased risk of motor vehicle crashes. The aim of this cross‐sectional study was to determine the prevalence and predictors of hypersomnolence (defined as an Epworth Sleepiness Scale score greater than 10) among truck drivers. Three hundred male truck drivers were studied. Quality of sleep was assessed by the Pittsburgh Sleep Quality Index, and the association between demographic, clinical, and occupational data with excessive sleepiness was analyzed. The mean daily sleep duration was 5.6±1.3 h, and poor quality of sleep was found in 46.3% of the individuals. Hypersomnolence was found in 46% of the drivers and was associated with younger age, snoring, and working >10 h without rest. A positive correlation between hypersomnolence and previous accidents was detected (p=0.005). These results show that sleep deprivation and hypersomnolence are frequent among truck drivers. The treatment of sleep‐disordered breathing and the implementation of educational programs, particularly targeting younger drivers and promoting increased awareness of the deleterious effects of sleep loss and work overload, may help to reduce hypersomnolence and accidents among truck drivers. 相似文献
28.
Diego Rodrigo Dolibaina Fernando Maia Silva Dias Olaf Hermann Hendrik Mielke Mirna Martins Casagrande 《Zoological Journal of the Linnean Society》2013,168(3):427-451
Three new species of Synargis Hübner, 1819, from Paraguay and southern and central Brazil are described: Synargis fandanga sp. nov. from Paraguay (Amambay and Paraguari) and southern Brazil (Paraná and Santa Catarina), Synargis rasqueada sp. nov. from central Brazil (Mato Grosso), and Synargis gorpa sp. nov. from southern Brazil (Paraná, Santa Catarina, and Rio Grande do Sul). Lectotypes are designated for Lemonias axenus Hewitson, 1876, Ematurgina axenus ochrophlegma Sitchel, 1911, Ematurgina acervata Seitz, 1932, and Ematurgina perrupta Seitz, 1932. Ematurgina ochrophlegma f. dissimilis Hayward, 1949, is a new synonym of Synargis bifasciata (Mengel, 1902), and Ematurgina ochrophlegma f. distincta Hayward, 1949, is a new synonym of Synargis axenus (Hewitson, 1876). The revalidation of E. perrupta Seitz, 1932, and the new status Synargis ochrophlegma (Stichel, 1911) are proposed. Ematurgina perrupta ab. roeberi Seitz, 1932, and Ematurgina bifasciata ochrophlegma ab. leucomelaina Breyer, 1930, are considered unavailable names. Based on a previous phylogenetic hypothesis, the phylogeny of the genus Synargis is reassessed, adding these new and revalidated taxa, and nine additional characters. The ‘Synargis regulus’ species group and the ‘Synargis axenus complex’ are recovered as monophyletic, with S. gorpa sp. nov. sister to the remaining species of the ‘S. axenus complex’. Additionally, an up‐to‐date geographical distribution map and a dichotomous key are provided, and the taxonomy of the taxa involved is discussed. © 2013 The Linnean Society of London 相似文献
29.
Luiz Claudio Pereira Ribeiro Cassia Cristina Alves Gon?alves Carla Maria Sena Andrade Slater Silvia Maia Farias de Carvalho Marzia Puccioni-Sohler 《Memórias do Instituto Oswaldo Cruz》2013,108(6):730-734
Intrathecal synthesis of human T-lymphotropic virus type 1 (HTLV-1) antibodies
(Abs) represents conclusive evidence of a specific immune response in the
central nervous system of HTLV-1 associated myelopathy/tropical spastic
paraparesis (HAM/TSP) patients. Western blotting (WB) for HTLV Abs in serum is a
confirmatory test for HTLV-1 infection. The aim of this study was to standardise
the Western blot to demonstrate the intrathecal pattern of Abs against HTLV-1
proteins in HAM/TSP patients. Paired cerebrospinal fluid (CSF) and serum samples
were selected from 20 patients with definite HAM/TSP, 19 HTLV-1 seronegative
patients and two HTLV-1 patients without definite HAM/TSP. The presence of
reactive bands of greater intensity in the CSF compared to serum (or bands in
only the CSF) indicated the intrathecal synthesis of anti-HTLV-1 Abs. All
definite HAM/TSP patients presented with an intrathecal synthesis of anti-HTLV-1
Abs; these Abs were not detected in the control patients. The most frequent
intrathecal targets of anti-HTLV-1 Abs were GD21, rgp46-I and p24 and, to a
lesser extent, p19, p26, p28, p32, p36, p53 gp21 and gp46. The intrathecal
immune response against env (GD21 and rgp46-I) and
gag (p24) proteins represents the most important humoral
pattern in HAM/TSP. This response may be used as a diagnostic marker,
considering the frequent association of intrathecal anti-HTLV-1 Ab synthesis
with HAM/TSP and the pathogenesis of this neurological disease. 相似文献
30.
Jaqueline Raymondi Silva Larissa Campos de Medeiros Vinícius Pinho dos Reis Juliana Helena Chávez Thiago Demarchi Munhoz Gustavo Puia Borges Otavio Augusto Brioschi Soares Carlos Henrique Coelho de Campos Rosangela Zacarias Machado Cristiane Divan Baldani Maria Luana Cristiny Rodrigues Silva Joice Lara Maia Faria Edson Elias da Silva Luiz Tadeu Moraes Figueiredo 《Memórias do Instituto Oswaldo Cruz》2013,108(7):921-923
Since the emergence of West Nile virus (WNV) in North America in 1999, there have been several reports of WNV activity in Central and South American countries. To detect WNV in Brazil, we performed a serological survey of horses from different regions of Brazil using recombinant peptides from domain III of WNV. Positive samples were validated with the neutralisation test. Our results showed that of 79 ELISA-positive horses, nine expressed WNV-specific neutralising antibodies. Eight of the infected horses were from the state of Mato Grosso do Sul and one was from the state of Paraíba. Our results provide additional evidence for the emergence of WNV in Brazil and for its circulation in multiple regions of the country. 相似文献