1,643 research outputs found
Mutational mechanism for DAB1 (ATTTC) n insertion in SCA37: ATTTT repeat lengthening and nucleotide substitution
Dynamic mutations by microsatellite instability are the molecular basis of a growing number of neuromuscular and neurodegenerative diseases. Repetitive stretches in the human genome may drive pathogenicity, either by expansion above a given threshold, or by insertion of abnormal tracts in nonpathogenic polymorphic repetitive regions, as is the case in spinocerebellar ataxia type 37 (SCA37). We have recently established that this neurodegenerative disease is caused by an (ATTTC)n insertion within an (ATTTT)n in a noncoding region of DAB1. We now investigated the mutational mechanism that originated the (ATTTC)n insertion within an ancestral (ATTTT)n . Approximately 3% of nonpathogenic (ATTTT)n alleles are interspersed by AT-rich motifs, contrarily to mutant alleles that are composed of pure (ATTTT)n and (ATTTC)n stretches. Haplotype studies in unaffected chromosomes suggested that the primary mutational mechanism, leading to the (ATTTC)n insertion, was likely one or more T>C substitutions in an (ATTTT)n pure allele of approximately 200 repeats. Then, the (ATTTC)n expanded in size, originating a deleterious allele in DAB1 that leads to SCA37. This is likely the mutational mechanism in three similar (TTTCA)n insertions responsible for familial myoclonic epilepsy. Because (ATTTT)n tracts are frequent in the human genome, many loci could be at risk for this mutational process.We are grateful to the families and individuals who participated in this work. We
thank Patricia Ribeiro for technical assistance. This study was financed by Fundo
Europeu de Desenvolvimento Regional (FEDER), through the COMPETE 2020
Operational Pro- gram for Competitiveness and Internationalization (POCI) of Portugal
2020, and by the FundacaĢo para a CieĢncia e a Tecnologia (FCT) and MinisteĢrio
da CieĢncia, Tecnologia e Ensino Superior (Portugal), in the framework of the project
POCI-01-0145-FEDER-029255; (PTDC/MED-GEN/29255/2017) to I.S. J.R.L. and
C.L.O. were sup- ported by scholarships from PEst-C/SAU/LA0002/2013. S.M. is
funded by the project IF/00930/2013/ CP1184/CT0002 from FCT. This work was
also funded by the Porto Neurosciences and Neurologic Disease Research Initiative
at the Instituto de InvestigaƧaĢo e InovaƧaĢo em SauĢde (Norte-01-0145-FEDER-
000008), supported by Norte Portugal Regional Operational Programme (NORTE
2020), under the PORTU- GAL 2020 Partnership Agreement with FEDER
Frequent and Persistent PLCG1 Mutations in Sezary Cells Directly Enhance PLC gamma 1 Activity and Stimulate NF kappa B, AP-1, and NFAT Signaling
Phospholipase C Gamma 1 (PLCG1) is frequently mutated in primary cutaneous T-cell lymphoma (CTCL). This study functionally interrogated nine PLCG1 mutations (p.R48W, p.S312L, p.D342N, p.S345F, p.S520F, p.R1158H, p.E1163K, p.D1165H, and the in-frame indel p.VYEEDM1161V) identified in SĆ©zary Syndrome, the leukemic variant of CTCL. The mutations were demonstrated in diagnostic samples and persisted in multiple tumor compartments over time, except in patients who achieved a complete clinical remission. In basal conditions, the majority of the mutations confer PLCĪ³1 gain-of-function activity through increased inositol phosphate production and the downstream activation of NFĪŗB, AP-1, and NFAT transcriptional activity. Phosphorylation of the p.Y783 residue is essential for the proximal activity of wild-type PLCĪ³1, but we provide evidence that activating mutations do not require p.Y783 phosphorylation to stimulate downstream NFĪŗB, NFAT, and AP-1 transcriptional activity. Finally, the gain-of-function effects associated with the p.VYEEDM1161V indel suggest that the C2 domain may have a role in regulating PLCĪ³1 activity. These data provide compelling evidence to support the development of therapeutic strategies targeting mutant PLCĪ³1
Molecular identification of Coccidioides spp. in soil samples from Brazil
<p>Abstract</p> <p>Background</p> <p>Since 1991 several outbreaks of acute coccidioidomycosis (CM) were diagnosed in the semi-arid Northeast of Brazil, mainly related to disturbance of armadillo burrows caused by hunters while digging them for the capture of these animals. This activity causes dust contaminated with arthroconidia of <it>Coccidioides posadasii</it>, which, once inhaled, cause the mycosis. We report on the identification of <it>C. posadasii </it>in soil samples related to outbreaks of CM.</p> <p>Results</p> <p>Twenty four soil samples had their DNA extracted and subsequently submitted to a semi-nested PCR technique using specific primers. While only 6 (25%) soil samples were positive for <it>C. posadasii </it>by mice inoculation, all (100%) were positive by the molecular tool.</p> <p>Conclusion</p> <p>This methodology represents a simple, sensitive and specific molecular technique to determine the environmental distribution of <it>Coccidioides </it>spp. in endemic areas, but cannot distinguish the species. Moreover, it may be useful to identify culture isolates. Key-words: 1. Coccidioidomycosis. 2. <it>Coccidioides </it>spp. 3. <it>C. posadasii</it>. 4. Semi-arid. 5. Semi-nested PCR</p
Phosphoproteomic differences in major depressive disorder postmortem brains indicate effects on synaptic function
There is still a lack in the molecular comprehension of major depressive disorder (MDD) although this condition affects approximately 10% of the world population. Protein phosphorylation is a posttranslational modification that regulates approximately one-third of the human proteins involved in a range of cellular and biological processes such as cellular signaling. Whereas phosphoproteome studies have been carried out extensively in cancer research, few such investigations have been carried out in studies of psychiatric disorders. Here, we present a comparative phosphoproteome analysis of postmortem dorsolateral prefrontal cortex tissues from 24 MDD patients and 12 control donors. Tissue extracts were analyzed using liquid chromatography mass spectrometry in a data-independent manner (LC-MSE). Our analyses resulted in the identification of 5,195 phosphopeptides, corresponding to 802 non-redundant proteins. Ninety of these proteins showed differential levels of phosphorylation in tissues from MDD subjects compared to controls, being 20 differentially phosphorylated in at least 2 peptides. The majority of these phosphorylated proteins were associated with synaptic transmission and cellular architecture not only pointing out potential biomarker candidates but mainly shedding light to the comprehension of MDD pathobiology
Plasma apolipoprotein J as a potential biomarker for Alzheimer\u27s disease: Australian Imaging, Biomarkers and Lifestyle study of aging
Introduction: For early detection of Alzheimer\u27s disease (AD), the field needs biomarkers that can be used to detect disease status with high sensitivity and specificity. Apolipoprotein J (ApoJ, also known as clusterin) has long been associated with AD pathogenesis through various pathways. The aim of this study was to investigate the potential of plasma apoJ as a blood biomarker for AD. Methods: Using the Australian Imaging, Biomarkers and Lifestyle (AIBL) study of aging, the present study assayed plasma apoJ levels over baseline and 18 months in 833 individuals. Plasma ApoJ levels were analyzed with respect to clinical classification, age, gender, apolipoprotein E (APOE) Īµ4 allele status, mini-mental state examination score, plasma amyloid beta (AĪ²), neocortical AĪ² burden (as measured by Pittsburgh compound B-positron emission tomography), and total adjusted hippocampus volume. Results: ApoJ was significantly higher in both mild cognitive impairment (MCI) and AD groups as compared with healthy controls (HC; P \u3c .0001). ApoJ significantly correlated with both standardized uptake value ratio (SUVR) and hippocampus volume and weakly correlated with the plasma AĪ²1-42/AĪ²1-40 ratio. Plasma apoJ predicted both MCI and AD from HC with greater than 80% accuracy for AD and greater than 75% accuracy for MCI at both baseline and 18-month time points. Discussion: Mean apoJ levels were significantly higher in both MCI and AD groups. ApoJ was able to differentiate between HC with high SUVR and HC with low SUVR via APOE Īµ4 allele status, indicating that it may be included in a biomarker panel to identify AD before the onset of clinical symptoms. Ā© 2016 The Authors
COMPARATIVE VOLUME EQUATIONS ADJUSTED WITH DATA OF STEM MEASUREMENTS AND STEM ANALYSIS
Este trabalho teve como objetivo comparar estimativas de volume com
casca, obtidas com equa\ue7\uf5es originadas partindo de dados da
cubagem com casca e an\ue1lise de tronco sem casca respectivamente. A
base de informa\ue7\uf5es para o desenvolvimento deste estudo foi
obtida em povoamentos de Pinus taeda L. no munic\uedpio de Ponte
Alta do Norte, Santa Catarina, sendo composta de duzentos e quarenta
\ue1rvores cubadas com casca em diferentes idades, as quais foram
selecionadas aleatoriamente e distribu\ueddas por classe de
di\ue2metro. Outra fonte de dados foi obtida com a an\ue1lise de
tronco sem casca de trinta \ue1rvores-amostra, distribu\ueddas
entre m\ue9dias e dominantes. Foram testados modelos matem\ue1ticos
para cada fonte de dados, afim de selecionar o de melhor ajuste e
precis\ue3o, com base no crit\ue9rio de sele\ue7\ue3o do Valor
Ponderado dos Escores dos Par\ue2metros Estat\uedsticos (VP). O
resultado do VP revelou a equa\ue7\ue3o de Schumacher-Hall como
mais adequada na estimativa do volume para as respectivas fontes de
dados. A compara\ue7\ue3o entre as estimativas de volume dos
modelos ajustados, partindo de dados da cubagem com casca e da
an\ue1lise de tronco sem casca, foi realizada com o teste
Qui-quadrado, que demonstrou n\ue3o haver diferen\ue7a
significativa entre elas, permitindo afirmar que \ue9 poss\uedvel
obter o volume com casca com base em uma equa\ue7\ue3o gerada com
dados de volume sem casca, obtidos pela an\ue1lise de tronco.This work aimed at comparing volume estimates with bark, obtained with
equations originated from data of the stem measurements with bark and
stem analysis without bark, respectively. The base of information for
the development of this study was obtained in forest of Pinus taeda
L. in the municipal district of Ponte Alta do Norte, Santa Catarina,
being composed by two hundred and forty trees measured with bark in
different ages, which were selected aleatorily and distributed by
diameter class. Another source of data was obtained with the stem
analysis without bark of thirty sample trees, distributed among
averages and dominant. Mathematical models were tested for each source
of data, in order to select the one of better adjustment and precision,
with base in the selection criterion of the Score Pondered Value of the
Statistical Parameters (VP). The result of VP revealed the equation of
Schumacher-Hall as the most appropriated one in the estimate of the
volume for the respective sources of data. The comparison between the
estimates of volume of the adjusted models starting from data of the
stem measurements with bark and of the stem analysis without bark was
accomplished with the test Qui-square, which demonstrated that there
area no significant differences to be significant difference among the
them allowing to affirm that it is possible to obtain the volume with
bark starting from an equation generated with volume data without bark,
obtained through the stem analysis
ANNUAL INCREMENT VARIATION ALONG STEM OF Pinus taeda L. IN DIFFERENT AGES AND POPULATION DENSITIES
A varia\ue7\ue3o do crescimento anual em diferentes alturas do
fuste de Pinus taeda L. foi estudada por meio da an\ue1lise de tronco
em \ue1rvores do estrato dominante e m\ue9dio. Foram coletadas
sec\ue7\uf5es transversais ao longo do fuste de 9
\ue1rvores-amostra, tomadas na base, \ue0 altura do peito (DAP), e
ap\uf3s, a cada metro. A amostragem foi constitu\uedda de 4
\ue1rvores provenientes de Canela, Rio Grande do Sul, em floresta com
17 anos de idade, submetida a um desbaste, e 5 \ue1rvores de Ponte
Alta do Norte, Santa Catarina, em floresta com 34 anos, submetida a
cinco desbastes. Os resultados, expressos na forma percentual do
incremento em \ue1rea basal na posi\ue7\ue3o \u201ci\u201d,
sobre o incremento em \ue1rea basal ao n\uedvel do DAP, mostraram a
forte varia\ue7\ue3o na deposi\ue7\ue3o anual de lenho ao longo
do fuste em fun\ue7\ue3o da densidade populacional, caracterizando
os efeitos da competi\ue7\ue3o e da libera\ue7\ue3o pela
execu\ue7\ue3o do desbaste. \uc1rvores sujeitas \ue0
competi\ue7\ue3o mostraram maior crescimento nas partes superiores
do fuste, enquanto que \ue1rvores sob menor concorr\ueancia
apresentaram maior crescimento em posi\ue7\uf5es inferiores,
facilmente identificadas pela forma e inclina\ue7\ue3o das curvas
de incremento.The variation of the annual growth in different heights of the stem of
Pinus taeda L. was studied through the stem analysis, accomplished in
dominant and medium stratum trees. Cross sections were collected along
the stem from 9 sample trees on the base, breast height diameter (BHD)
and after these positions, at every meter. The sampling was constituted
of 4 trees coming from Canela, Rio Grande do Sul, in a 17-years-old
stand, submitted to one thinning, and 6 trees from Ponte Alta do Norte,
Santa Catarina, in a 34-years-old stand, submitted to five thinnings.
The results, expressed in percentage of the basal area increment in
several positions of the tree height, showed strong variation in the
annual deposition of wood along the stem in function of the
populational density, characterizing the effects of the competition and
of the thinning liberation. Trees subjected to the competition showed
larger growth on top parts of the stem, while trees under smaller
competition presented larger growth on lower positions, easily
identified by the form and inclination of the increment curves
Relationship between birth weight and overweight/obesity among students in FlorianĆ³polis, Santa Catarina, Brazil: a retrospective cohort study
Teaching and learning in a multilingual Europe: findings from a cross-European study
School classrooms within the EU are multilingual learning environments. The diversity of pupils in classrooms raises significant challenges for teachers, but to date, there are no data from large-scale surveys that compare views within and across European countries. A bespoke questionnaire was designed to examine views of current classroom learning environments with respect to the multilingualism. The questionnaire was piloted and subsequently completed by 2792 teachers across different European countries. Eleven countries provided sufficient data for analyses. Results from structural equation modelling showed that teachersā attitudes could be reliably measured across Europe with the use of carefully devised questionnaire, whose loading and factor structure remained invariant across countries. Teachersā views about multilingualism were most challenged by the numbers of children in their classes, not the percentage of multilingual pupils in the class. Countries differed in how they perceived multilingualism, with their differences leading to distinctive country clusters. Gender and education level (elementary vs. secondary) differences were also observed irrespective of country. These findings enhance our understanding of the role that the characteristics of teachers and their classrooms play in a multilingual setting across diverse European settings. The practical relevance of the results and new opportunities for teacher training are discussed
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