3,082 research outputs found
Chronic hemolytic anemia is associated with a new glucose-6-phosphate dehydrogenase in-frame deletion in an older woman
Glucose-6-phosphate dehydrogenase (G6PD) deficiency, an X-linked disorder, is usually observed in hemizygote males and very rarely in females. The G6PD class 1 variants, very uncommon, are associated with chronic hemolytic anemia. Here we report a Portuguese woman who suffered in her sixties from a chronic hemolytic anemia due to G6PD deficiency. Molecular studies revealed heterozygosity for an in-frame 18-bp deletion, mapping to exon 10 leading to a deletion of 6 residues, 362-367 (LNERKA), which is a novel G6PD class 1 variant, G6PD Tondela. Two of her three daughters, asymptomatic, with G6PD activity within the normal range, are heterozygous for the same deletion. The patient's leukocyte and reticulocyte mRNA studies revealed an almost exclusive expression of the mutant allele, explaining the chronic hemolytic anemia. Patient whole blood genomic DNA HUMARA assay showed a balanced pattern of X chromosome inactivation (XCI), but granulocyte DNA showed extensive skewing, harboring the mutated allele, implying that in whole blood, lymphocyte DNA, with a very long lifetime, may cover up the current high XCI skewing. This observation indicates that HUMARA assay in women should be assessed in granulocytes and not in total leukocytes
Patterns of Parental Reactions to Their Children’s Negative Emotions: A Cluster Analysis with a Clinical Sample
Parents' emotion socialization practices are an important source of influence in the development of children's emotional competencies This study examined parental reactions to child negative emotions in a clinical sample using a cluster analysis approach and explored the associations between clusters of parents' reactions and children's and parents' adjustment. The sample comprised 80 parents of Portuguese children (aged 3-13 years) attending a child and adolescent psychiatry unit. Measures to assess parental reactions to children's negative emotions, parents' psychopathological symptoms, parents' emotion dysregulation, and children's adjustment were administered to parents. Model-based cluster analysis resulted in three clusters: low unsupportive, high supportive, and inconsistent reactions clusters. These clusters differed significantly in terms of parents' psychopathological symptoms, emotion dysregulation, and children's adjustment. A pattern characterized by high supportive reactions to the child's emotions was associated with higher levels of children's adjustment. On the other hand, an inconsistent reactions pattern was associated with the worst indicators of children's adjustment and parental emotion dysregulation. These results suggest the importance of supporting parents of children with emotional and behavioural problems so that they can be more responsive to their children's emotional manifestations.info:eu-repo/semantics/publishedVersio
An analysis-ready and quality controlled resource for pediatric brain white-matter research
We created a set of resources to enable research based on openly-available diffusion MRI (dMRI) data from the Healthy Brain Network (HBN) study. First, we curated the HBN dMRI data (N = 2747) into the Brain Imaging Data Structure and preprocessed it according to best-practices, including denoising and correcting for motion effects, susceptibility-related distortions, and eddy currents. Preprocessed, analysis-ready data was made openly available. Data quality plays a key role in the analysis of dMRI. To optimize QC and scale it to this large dataset, we trained a neural network through the combination of a small data subset scored by experts and a larger set scored by community scientists. The network performs QC highly concordant with that of experts on a held out set (ROC-AUC = 0.947). A further analysis of the neural network demonstrates that it relies on image features with relevance to QC. Altogether, this work both delivers resources to advance transdiagnostic research in brain connectivity and pediatric mental health, and establishes a novel paradigm for automated QC of large datasets
A reduction method for semi-infinite programming by means of a global stochastic approach
We describe a reduction algorithm for solving semi-infinite programming problems. The proposed algorithm uses the simulated annealing method equipped with a function stretching as a multi-local procedure, and a penalty technique for the finite optimization process. An exponential penalty merit function is reduced along each search direction to ensure convergence from any starting point. Our preliminary numerical results seem to show that the algorithm is very promising in practice.Algoritmi Research CenterFundação para a Ciência e a Tecnologia (FCT) - bolsa POCI/MAT/58957/200
Interaction of paraoxonase-192 polymorphism with low HDL-cholesterol in coronary artery disease risk.
A doença coronária (DC) é a principal causa
de mortalidade nos paĂses desenvolvidos. O
aumento da peroxidação lipĂdica está associado
com a progressĂŁo acelerada da arteriosclerose.
A Paraoxonase (PON1) Ă© uma
enzima antioxidante, que protege contra a
peroxidação lipĂdica e a DC. A actividade
da PON1 está sob controlo genético e a sua
base molecular consiste num polimorfismo
do gene da PON1 que apresenta duas isoformas
comuns: a forma nativa, Q (192 Gln)
com elevada capacidade de protecção das
LDL da peroxidação lipĂdica in vitro, e a
isoforma mutada R (192 Arg) com baixa
capacidade de protecção.
Objectivo: O objectivo deste trabalho foi
investigar a interacção entre o alelo R do
gene da PON 1 e os nĂveis plasmáticos
baixos de colesterol HDL, no risco do
aparecimento da DC.
MĂ©todos: Participaram no estudo 818 indivĂduos,
298 doentes coronários com idade
média 55.0±10.3 anos, 78.9% do sexo masculino,
e 520 controlos, com uma idade
média de 53.3±11, 7 anos, 72, 5% do sexo
masculino, tendo casos e controlos sido
emparelhados por idade e sexo. Foi considerado
um valor <de 40 mg/dl (0,90
mmol/L), nos homens e <de 50 mg/dl (1,11
mmol/L), nas mulheres como um nĂvel baixo
de Colesterol HDL. As comparações
genotĂpicas, entre casos e controlos, foram efectuadas pelo teste do Chi-quadrado. A
significância estatĂstica foi aceite para valores
de p <0,05. Para determinar o risco
relativo de DC, em relação ao genótipo RR
e aos nĂveis baixos de colesterol HDL, foi
usada uma análise univariada e foram utilizadas
as tabelas epidemiolĂłgicas 4x2 e
medidas de sinergismo (modelo aditivo - SI
e multiplicativo - SIM) para determinar a
interacção entre o genĂłtipo RR e os nĂveis
baixos de colesterol HDL. Foi finalmente
calculado o excesso de risco relativo (RERI)
e proporção atribuĂda Ă interacção (AP).
Resultados: A PON 1 192 RR está associada
à DC [OR=1,61; p=0,043] para toda a população.
A associação de nĂveis baixos de
HDL com o genĂłtipo 192 RR mostrou um
aumento do risco de DC (OR=17,38; p
<0,0001) comparada aos nĂveis normais de
HDL associados ao mesmo genĂłtipo
(OR=1,39; p=0,348) e aos nĂveis baixos de
HDL sem o genĂłtipo RR (OR=7,79; p
<0,0001). ĂŤndices de Sinergismo: SI= 2,3;
SIM = 1.6; RERI=9,2; AP=0,53.
ConclusĂŁo: Estes dados sugerem a existĂŞncia
de um efeito sinérgico entre o genótipo
192 RR da PON1 e os valores baixos de
colesterol HDL, na emergĂŞncia de DC, pois
este genĂłtipo aumentou o risco de DC, em
especial, na população com nĂveis plasmáticos
baixos de colesterol HDL. A proporção
de DC que pode ser atribuĂda a esta interacção
(AP) foi de 0,53 significando que
53% da DC que surgiu nestes indivĂduos,
foi explicada por esta interacção.INTRODUCTION:
Coronary artery disease (CAD) is the main cause of mortality in developed countries. Increased lipid peroxidation is associated with accelerated progression of atherosclerosis. Paraoxonase (PON1) is an antioxidant enzyme bound to high-density lipoprotein (HDL), which protects against lipid peroxidation and coronary artery disease. PON1 activity is under genetic control and its molecular basis is a polymorphism in the PON1 gene that shows two common isoforms: the wild Q form (192 Gln) with high ability to protect LDL from lipid peroxidation in vitro, and the mutated R (Arg) form with lower ability.
AIM:
To explore the interaction of the R allele of the paraoxonase gene and low HDL-cholesterol concentrations in CAD risk.
METHODS:
The study population consisted of 818 individuals, 298 coronary patients, aged 55.0 +/- 10.3 years, 78.9% male, and 520 age and gender matched healthy controls, aged 53.3 +/- 11.7 years, 72.5% male. Low HDL-cholesterol was defined as < 0.90 mmol/l in men and < 1.11 mmol/l in women. Comparisons of genotypes between cases and controls were performed by a chi-square test. Statistical significance was accepted at p < 0.05. Odds ratios and 95% confidence intervals for the RR genotypes and HDL-deficient subjects were computed using univariate analysis (2 x 2 tables). To determine the interaction between the RR paraoxonase genotype and HDL-deficient subjects, we used 4 x 2 epidemiologic tables and synergy measures: the additive model (Rothman's synergy index, SI) and multiplicative model (Khoury's synergy index, SIM). The relative excess risk due to interaction (RERI) and the attributable proportion (AP) due to interaction (Rothman) were calculated.
RESULTS:
The PON1 RR192 polymorphism was associated with coronary heart disease (OR = 1.61; p = 0.043) in the whole population. HDL-deficient subjects with the RR192 genotype showed increased risk for CAD (OR = 17.38; p < 0.0001) compared to those with normal HDL and RR192 (OR = 1.39; p = 0.348) and HDL-deficient subjects not carrying the RR genotype (OR = 7.79; p < 0.0001). Synergy measures were SI = 2.3, SIM = 1.6; RERI = 9.2.
CONCLUSION:
These data suggest the existence of a synergistic effect of the PON1 RR192 genotype (with lower antioxidant ability) and HDL-deficient subjects in risk for development of CAD. The AP due to this interaction was 0.53, meaning that 53% of CAD was explained by this interaction.info:eu-repo/semantics/publishedVersio
A brain-sparing diphtheria toxin for chemical genetic ablation of peripheral cell lineages.
Conditional expression of diphtheria toxin receptor (DTR) is widely used for tissue-specific ablation of cells. However, diphtheria toxin (DT) crosses the blood-brain barrier, which limits its utility for ablating peripheral cells using Cre drivers that are also expressed in the central nervous system (CNS). Here we report the development of a brain-sparing DT, termed BRAINSPAReDT, for tissue-specific genetic ablation of cells outside the CNS. We prevent blood-brain barrier passage of DT through PEGylation, which polarizes the molecule and increases its size. We validate BRAINSPAReDT with regional genetic sympathectomy: BRAINSPAReDT ablates peripheral but not central catecholaminergic neurons, thus avoiding the Parkinson-like phenotype associated with full dopaminergic depletion. Regional sympathectomy compromises adipose tissue thermogenesis, and renders mice susceptible to obesity. We provide a proof of principle that BRAINSPAReDT can be used for Cre/DTR tissue-specific ablation outside the brain using CNS drivers, while consolidating the link between adiposity and the sympathetic nervous system
The Effect of Transposable Element Insertions on Gene Expression Evolution in Rodents
Background:Many genomes contain a substantial number of transposable elements (TEs), a few of which are known to be involved in regulating gene expression. However, recent observations suggest that TEs may have played a very important role in the evolution of gene expression because many conserved non-genic sequences, some of which are know to be involved in gene regulation, resemble TEs. Results:Here we investigate whether new TE insertions affect gene expression profiles by testing whether gene expression divergence between mouse and rat is correlated to the numbers of new transposable elements inserted near genes. We show that expression divergence is significantly correlated to the number of new LTR and SINE elements, but not to the numbers of LINEs. We also show that expression divergence is not significantly correlated to the numbers of ancestral TEs in most cases, which suggests that the correlations between expression divergence and the numbers of new TEs are causal in nature. We quantify the effect and estimate that TE insertion has accounted for ~20% (95% confidence interval: 12% to 26%) of all expression profile divergence in rodents. Conclusions:We conclude that TE insertions may have had a major impact on the evolution of gene expression levels in rodents
Independent association of the variant rs1333049 at the 9p21 locus and coronary heart disease.
Introdução: Estudos recentes de associação
genĂłmica em larga escala (GWAS)
identificaram vários polimorfismos de um
Ăşnico nucleĂłtido (SNP), localizados no locus
9p21, associados com doença arterial
coronária (DAC). De entre eles o SNP
rs1333049 demonstrou uma associação
consistente com a DAC tendo sido
reproduzida, com sucesso,
em várias populações.
Objectivo: Investigar se a nova variante
rs1333049, no cromossoma 9p21,
Ă© um factor de risco independente
para DAC, na população Portuguesa.
Material e métodos: Estudo caso-controlo,
que incluiu 1406 indivĂduos, 723 doentes
coronários internados consecutivamente
(idade média de 53,7±8,9 anos 79,9% do
sexo masculino) e 683 controlos
sem doença coronária (idade média
de 53,3±10,5 anos, 73,9 % do sexo
masculino) seleccionados para nĂŁo serem
significativamente diferentes quanto ao sexo
e idade. Estudou-se o SNP rs1333049,
em todos os indivĂduos,
com recurso à técnica convencionada de
PCR combinada com a técnica TaqMan (Applied Biosystems). Determinou-se a
distribuição alĂ©lica e genotĂpica (C/G), odds
ratio e respectivo intervalo de confiança
para risco de DAC.
Foi construĂdo um modelo de regressĂŁo
logĂstica forward wald ajustado para a
idade, sexo, factores de risco convencionais,
marcadores bioquĂmicos e genĂłtipos em
estudo, afim de avaliar quais as variáveis
associadas de forma significativa e
independente com DAC.
Resultados: 60% dos doentes coronários e
53% dos controlos apresentaram o alelo C
(OR=1,33; p=0,0002), 35,7% dos doentes e
29,3% dos controlos tinham o genĂłtipo
homozigoto CC (OR=1,34;p=0,010).
O heterozigoto CG estava presente em
48,1% dos doentes e 47% nos controlos,
nĂŁo atingindo significância estatĂstica, para
risco vascular (OR=1,05;p=0,670). ApĂłs
análise multivariada de regressĂŁo logĂstica o
genĂłtipo CC do cromossoma 9p21 ficou na
equação com um OR=1,7, p=0,018 e o
genĂłtipo heterozigoto
CG com um OR=1,5, p=0,048.
ConclusĂŁo: Com o presente trabalho
replicou-se, numa população portuguesa, o
risco coronário ligado à nova variante
rs1333049 do cromossoma 9p21.
A robustez deste genĂłtipo,
tanto em homo como em heterozigotia,
tem sido consistente e relevante na
estratificação de risco para a DAC,
mesmo em contextos populacionais
muito diversos. Nestas circunstâncias,
a utilização do genótipo CC ou CG
poderá vir a revelar-se útil
para a previsĂŁo do risco de DAC
na nossa população.INTRODUCTION:
Recent genome-wide association studies have identified single-nucleotide polymorphisms (SNPs) at the 9p21 locus as risk factors for coronary artery disease (CAD). Among them, the SNP rs1333049 has demonstrated a consistent association with CAD, which has been successfully replicated in several populations.
AIM:
To investigate whether the SNP rs1333049 located on the 9p21 chromosome is an independent risk factor for CAD in a Portuguese population.
METHODS:
We performed a case-control study which included 1406 individuals, 723 consecutive coronary patients (mean age 53.71 +/- 8.9 years, 79.9% male and 683 controls without coronary disease (mean age 53.3 +/- 10.5 years, 73.9% male). Cases and controls were selected so as not to be significantly different in terms of gender and age. We studied the SNP rs1333049 at the 9p21 locus in all individuals, using standard PCR combined with the TaqMan technique (Applied Biosystems). The allelic and genotype distribution (C/G), odds ratios and corresponding confidence intervals for CAD risk were determined. A forward Wald logistic regression analysis model was constructed, adjusted for age, gender, conventional risk factors, biochemical markers and the genotypes under study, in order to determine which variables were linked significantly and independently with CAD.
RESULTS:
The C allele was found in 60% of the CAD patients and 53% of the controls, with OR = 1.33; p = 0.0002. The CC genotype appeared in 35.7% of CAD patients, with OR = 1.34, p = 0.010. The heterozygous CG genotype was present in 48.1% of the CAD patients and 47% of the controls, and did not present vascular risk (OR = 1.05, p = 0.670). After logistic regression analysis, the CC genotype remained in the equation with OR = 1.7; p = 0.018 and CG with OR = 1.5, p = 0.048.
CONCLUSION:
In the present study we replicated the coronary risk linked to the recently discovered variant rs1333049 on the 9p21 chromosome in a Portuguese population. Although the mechanism underlying the risk is still unknown, the robustness of this risk allele in risk stratification for CAD has been consistent, even in very different populations. The presence of the CC or CG genotype may thus prove to be useful for predicting the risk of developing CAD in the Portuguese population.info:eu-repo/semantics/publishedVersio
Serum amyloid A proteins reduce bone mass during mycobacterial infections
IntroductionOsteopenia has been associated to several inflammatory conditions, including mycobacterial infections. How mycobacteria cause bone loss remains elusive, but direct bone infection may not be required. MethodsGenetically engineered mice and morphometric, transcriptomic, and functional analyses were used. Additionally, inflammatory mediators and bone turnover markers were measured in the serum of healthy controls, individuals with latent tuberculosis and patients with active tuberculosis. Results and discussionWe found that infection with Mycobacterium avium impacts bone turnover by decreasing bone formation and increasing bone resorption, in an IFN gamma- and TNF alpha-dependent manner. IFN gamma produced during infection enhanced macrophage TNF alpha secretion, which in turn increased the production of serum amyloid A (SAA) 3. Saa3 expression was upregulated in the bone of both M. avium- and M. tuberculosis-infected mice and SAA1 and 2 proteins (that share a high homology with murine SAA3 protein) were increased in the serum of patients with active tuberculosis. Furthermore, the increased SAA levels seen in active tuberculosis patients correlated with altered serum bone turnover markers. Additionally, human SAA proteins impaired bone matrix deposition and increased osteoclastogenesis in vitro. Overall, we report a novel crosstalk between the cytokine-SAA network operating in macrophages and bone homeostasis. These findings contribute to a better understanding of the mechanisms of bone loss during infection and open the way to pharmacological intervention. Additionally, our data and disclose SAA proteins as potential biomarkers of bone loss during infection by mycobacteria.This article is a result of the project HEALTH-UNORTE: Setting-up biobanks and regenerative medicine strategies to boost research in cardiovascular, musculoskeletal, neurological, oncological, immunological and infectious diseases (NORTE-01-0145-FEDER-000039), supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). This work was supported by KOG-202108-00929 from the European Haematology Society, awarded to AG. Work in the MS lab was financed by FEDER - Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020 - Operacional Programme for Competitiveness and Internationalisation (POCI), Portugal 2020, and by Portuguese funds through FCT - Fundacao para a Ciencia e a Tecnologia/Ministerio da Ciencia, Tecnologia e Ensino Superior in the framework of the project POCI-01-0145-FEDER-028955 (PTDC/SAU-INF/28955/2017). AG and MS are supported by an Individual Scientific Employment contract (CEECIND/00048/2017; CEECIND/00241/2017 respectively). DS acknowledges the Portuguese Foundation for Science and Technology (FCT) for the Post-Doc fellowship (SFRH/BPD/115341/2016). RP, DS and AF have PhD grants (SFRH/BD/145217/2019; SFRH/BD/143536/2019; 2020.05949.BD, respectively) financed by FCT
Transient peak-strain matching partially recovers the age-impaired mechanoadaptive cortical bone response
Mechanoadaptation maintains bone mass and architecture; its failure underlies age-related decline in bone strength. It is unclear whether this is due to failure of osteocytes to sense strain, osteoblasts to form bone or insufficient mechanical stimulus. Mechanoadaptation can be restored to aged bone by surgical neurectomy, suggesting that changes in loading history can rescue mechanoadaptation. We use non-biased, whole-bone tibial analyses, along with characterisation of surface strains and ensuing mechanoadaptive responses in mice at a range of ages, to explore whether sufficient load magnitude can activate mechanoadaptation in aged bone. We find that younger mice adapt when imposed strains are lower than in mature and aged bone. Intriguingly, imposition of short-term, high magnitude loading effectively primes cortical but not trabecular bone of aged mice to respond. This response was regionally-matched to highest strains measured by digital image correlation and to osteocytic mechanoactivation. These data indicate that aged bone’s loading response can be partially recovered, non-invasively by transient, focal high strain regions. Our results indicate that old murine bone does respond to load when the loading is of sufficient magnitude, and bones’ age-related adaptation failure may be due to insufficient mechanical stimulus to trigger mechanoadaptation
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