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1.
Environ Res ; 231(Pt 3): 116280, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37257742

RESUMO

This work presents a one-step synthesis methodology for preparing a hydrochar (HC) doped with TiO2 (HC-TiO2) for its application on the degradation of crystal violet (CV) using UV and visible radiation. Byrsonima crassifolia stones were used as precursors along with TiO2 particles. The HC-TiO2 sample was synthesized at 210 °C for 9 h using autogenous pressure. The photocatalyst was characterized to evaluate the TiO2 dispersion, specific surface area, graphitization degree, and band-gap value. Finally, the degradation of CV was investigated by varying the operating conditions of the system, the reuse of the catalyst, and the degradation mechanism. The physicochemical characterization of the HC-TiO2 composite showed good dispersion of TiO2 in the carbonaceous particle. The presence of TiO2 on the hydrochar surface yields a bandgap value of 1.17 eV, enhancing photocatalyst activation with visible radiation. The degradation results evidenced a synergistic effect with both types of radiation due to the hybridized π electrons in the sp2-hybridized structures in the HC surface. The degradation percentages were on average 20% higher using UV radiation than visible radiation under the following conditions: [CV] = 20 mg/L, 1 g/L of photocatalyst load, and pH = 7.0. The reusability experiments demonstrated the feasibility of reusing the HC-TiO2 material up to 5 times with a similar photodegradation percentage. Finally, the results indicated that the HC-TiO2 composite could be considered an efficient material for the photocatalytic treatment of water contaminated with CV.


Assuntos
Violeta Genciana , Raios Ultravioleta , Luz , Titânio/química , Catálise
2.
Arch Virol ; 164(4): 1205-1208, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30729309

RESUMO

Chikungunya virus (CHIKV) is a reemerging arbovirus of the family Togaviridae that causes CHIKV fever, a disease that can extend from weeks to years depending on whether clinical signs of arthralgia persist. CHIKV is mainly transmitted by Aedes aegypti mosquitoes and possibly reached the Americas in 2013, causing an outbreak in Brazil in 2015. So far, two evolutionary lineages of CHIKV have been reported in Brazil: the Asian and the East-Central-South African (ECSA) lineages. In this study, six CHIKV isolates circulating in midwestern Brazil (Mato Grosso state) were isolated from patient sera, and their complete genomes were sequenced using a high-throughput sequencing platform. All of these isolates shared high nucleotide sequence similarity with CHIKV isolates from northeastern Brazil and were found to belong to the ECSA lineage. These CHIKV isolates did not contain the A226V or L210Q mutations that are associated with increased transmissibility by A. albopictus, suggesting that the CHIKV isolates circulating in midwestern Brazil are predominantly transmitted by A. aegypti.


Assuntos
Febre de Chikungunya/virologia , Vírus Chikungunya/isolamento & purificação , Genoma Viral , Sequência de Bases , Brasil/epidemiologia , Febre de Chikungunya/epidemiologia , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Humanos , Dados de Sequência Molecular , Filogenia
3.
Mol Psychiatry ; 22(8): 1110-1118, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28555078

RESUMO

Stress, a well-known sculptor of brain plasticity, is shown to suppress hippocampal neurogenesis in the adult brain; yet, the underlying cellular mechanisms are poorly investigated. Previous studies have shown that chronic stress triggers hyperphosphorylation and accumulation of the cytoskeletal protein Tau, a process that may impair the cytoskeleton-regulating role(s) of this protein with impact on neuronal function. Here, we analyzed the role of Tau on stress-driven suppression of neurogenesis in the adult dentate gyrus (DG) using animals lacking Tau (Tau-knockout; Tau-KO) and wild-type (WT) littermates. Unlike WTs, Tau-KO animals exposed to chronic stress did not exhibit reduction in DG proliferating cells, neuroblasts and newborn neurons; however, newborn astrocytes were similarly decreased in both Tau-KO and WT mice. In addition, chronic stress reduced phosphoinositide 3-kinase (PI3K)/mammalian target of rapamycin (mTOR)/glycogen synthase kinase-3ß (GSK3ß)/ß-catenin signaling, known to regulate cell survival and proliferation, in the DG of WT, but not Tau-KO, animals. These data establish Tau as a critical regulator of the cellular cascades underlying stress deficits on hippocampal neurogenesis in the adult brain.


Assuntos
Neurogênese/fisiologia , Proteínas tau/metabolismo , Animais , Astrócitos/metabolismo , Proliferação de Células , Sobrevivência Celular , Giro Denteado/metabolismo , Modelos Animais de Doenças , Quinase 3 da Glicogênio Sintase/metabolismo , Hipocampo/metabolismo , Masculino , Camundongos , Plasticidade Neuronal/fisiologia , Neurônios/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Transdução de Sinais , Estresse Fisiológico , beta Catenina/metabolismo
4.
Mol Psychiatry ; 22(12): 1725-1734, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27777416

RESUMO

Hippocampal neurogenesis has been proposed to participate in a myriad of behavioral responses, both in basal states and in the context of neuropsychiatric disorders. Here, we identify activating protein 2γ (AP2γ, also known as Tcfap2c), originally described to regulate the generation of neurons in the developing cortex, as a modulator of adult hippocampal glutamatergic neurogenesis in mice. Specifically, AP2γ is present in a sub-population of hippocampal transient amplifying progenitors. There, it is found to act as a positive regulator of the cell fate determinants Tbr2 and NeuroD, promoting proliferation and differentiation of new glutamatergic granular neurons. Conditional ablation of AP2γ in the adult brain significantly reduced hippocampal neurogenesis and disrupted neural coherence between the ventral hippocampus and the medial prefrontal cortex. Furthermore, it resulted in the precipitation of multimodal cognitive deficits. This indicates that the sub-population of AP2γ-positive hippocampal progenitors may constitute an important cellular substrate for hippocampal-dependent cognitive functions. Concurrently, AP2γ deletion produced significant impairments in contextual memory and reversal learning. More so, in a water maze reference memory task a delay in the transition to cognitive strategies relying on hippocampal function integrity was observed. Interestingly, anxiety- and depressive-like behaviors were not significantly affected. Altogether, findings open new perspectives in understanding the role of specific sub-populations of newborn neurons in the (patho)physiology of neuropsychiatric disorders affecting hippocampal neuroplasticity and cognitive function in the adult brain.


Assuntos
Ansiedade/metabolismo , Cognição/fisiologia , Depressão/metabolismo , Hipocampo/metabolismo , Neurogênese/fisiologia , Fator de Transcrição AP-2/metabolismo , Animais , Ansiedade/patologia , Proliferação de Células/fisiologia , Proteínas de Ligação a DNA , Depressão/patologia , Hipocampo/citologia , Aprendizagem/fisiologia , Masculino , Memória/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas do Tecido Nervoso/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Proteínas Nucleares/metabolismo , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/metabolismo , Nicho de Células-Tronco/fisiologia , Proteínas com Domínio T/metabolismo , Fator de Transcrição AP-2/genética
5.
J Public Health (Oxf) ; 39(2): e56-e62, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27521924

RESUMO

Background: The consequences of financial crises on patients' use of healthcare have been widely discussed. This paper seeks to ascertain whether the position of key players, i.e. doctors, may reveal realities other than those officially reported about the 2008 financial crisis. Methods: In 2013-14, a national survey of doctors was conducted in Portugal, which received international assistance in the wake of the financial crisis. An exploratory model comprising descriptive statistics, regression and independence analyses focused on doctors' experience of patients' use of medications, consultations, exams and treatment services, and whether they stopped treatments. Results: According to doctors, an unspecified number of patients experienced difficulties using healthcare as more patients requested prescriptions for cheaper medications or simply stopped treatments. Significant variations were found according to speciality, years of practice and sector of activity. Conclusions: Cost-containment mechanisms are regarded as necessary. However, the evidence indicated a side effect, i.e. a decrease in patients' ability to use healthcare, including in the National Health Service (NHS). It also highlighted the need to listen to health professionals as key informants on patient's behaviour and the daily functioning of health services.


Assuntos
Recessão Econômica/estatística & dados numéricos , Programas Nacionais de Saúde/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Médicos/psicologia , Cooperação e Adesão ao Tratamento/psicologia , Cooperação e Adesão ao Tratamento/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Portugal
6.
Bioprocess Biosyst Eng ; 38(2): 229-35, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25090981

RESUMO

In recent decades, the production of compounds from microorganisms has increased significantly. Glycerol as a source of substrate appears to have great potential, due to its large supply because of the increase in biodiesel production. This paper will discuss the multiplicity of steady states for the production of 1,3-propanediol from glycerol by Clostridium butyricum, employing a model that takes into account inhibition by fermentation products. The theoretical study of bifurcation enabled us to make a qualitative adjustment to the various experimental steady states, using the theoretical steady states obtained from the AUTO2007 program. The theoretical model parameters were varied to fit qualitatively the values of the experimental steady states. In addition, this work is a qualitative study, using experimental steady states that can be used as an initial study for more advanced work on optimizing the production of 1,3-propanediol.


Assuntos
Reatores Biológicos/microbiologia , Clostridium butyricum/fisiologia , Glicerol/metabolismo , Modelos Biológicos , Propilenoglicóis/metabolismo , Proliferação de Células/fisiologia , Simulação por Computador , Propilenoglicóis/isolamento & purificação
7.
Br J Cancer ; 110(12): 2945-54, 2014 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-24823697

RESUMO

BACKGROUND: The miRNA deregulation is commonly observed in human malignancies, where they act as tumour suppressors or oncogenes. Despite the association of several miRNAs with bladder cancer, little is known about the miRNAs that contribute to bladder cancer progression from non-muscle invasive (NMI) to muscle-invasive (MI) disease. METHODS: We first profiled the expression of miRNAs and mRNAs in a cohort of urothelial carcinomas and further characterised the role of miR-126 in invasion, as it emerged as the most downregulated miRNA between MI and NMI tumours. RESULTS: We found that restoration of miR-126 levels attenuated the invasive potential of bladder cancer cells. Mechanistically, we identified the role of miR-126 in invasion through its ability to target ADAM9. Notably, a significant inverse correlation between miR-126 and ADAM9 expression was observed, where ADAM9 was upregulated in MI bladder cancer cells. While knockdown of ADAM9 attenuated the invasiveness of cells with low miR-126 levels, experimental upregulation of ADAM9 recapitulated the invasive phenotype. Furthermore, ADAM9 expression assessed by immunohistochemistry significantly correlated with poor prognosis in patients with urothelial carcinoma. CONCLUSIONS: In this study we describe the role of miR-126 in bladder cancer progression, identifying miR-126 and ADAM9 as potential clinical biomarkers of disease aggressiveness.


Assuntos
Proteínas ADAM/genética , Biomarcadores Tumorais/genética , Proteínas de Membrana/genética , MicroRNAs/genética , MicroRNAs/fisiologia , Neoplasias da Bexiga Urinária/patologia , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Prognóstico , Interferência de RNA , Neoplasias da Bexiga Urinária/genética
8.
Int J Sports Med ; 35(5): 371-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24129990

RESUMO

The aim of the present study was to analyze the effects of age on cardiorespiratory fitness (CRF), muscle strength and heart rate (HR) response to exercise adaptation in women in response to a long-term twice-weekly combined aerobic and resistance exercise program. 85 sedentary women, divided into young (YG; n=22, 30.3 ± 6.2 years), early middle-aged (EMG; n=28, 44.1 ± 2.5 years), late middle-aged (LMG; n=20, 56.7 ± 3.5 years) and older (OG; n=15, 71.4 ± 6.9 years) groups, had their CRF, muscle strength (1-repetition maximum test) and HR response to exercise (graded exercise test) measured before and after 12 months of combined exercise training. Exercise training improved CRF and muscle strength in all age groups (P<0.05), and no significant differences were observed between groups. Exercise training also improved resting HR and recovery HR in YG and EMG (P<0.05), but not in LMG and OG. Maximal HR did not change in any group. Combined aerobic and resistance training at a frequency of 2 days/week improves CRF and muscle strength throughout the lifespan. However, exercise-induced improvements in the HR recovery response to exercise may be impaired in late middle-aged and older women.


Assuntos
Envelhecimento/fisiologia , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Aptidão Física/fisiologia , Adulto , Teste de Esforço , Tolerância ao Exercício/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Força Muscular/fisiologia , Educação Física e Treinamento/métodos , Estudos Prospectivos , Treinamento Resistido , Adulto Jovem
9.
Neurocirugia (Astur) ; 25(2): 81-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23845268

RESUMO

The presence of a cerebral aneurysm in patients with pituitary adenoma is a rare event. Diagnostic suspicion may stem from magnetic resonance imaging, which should lead to complementary investigation. As for treatment, even in conditions in which there has been no previous bleeding, the simultaneous approach should be considered, prioritising the aneurysm most of the time. The present report describes the case of a patient with a history of pituitary macroadenoma, who had undergone a partial transsphenoidal resection ten years earlier. Admission to our service occurred after a sudden headache followed by mental confusion. A cranial computed tomography showed subarachnoid haemorrhage and expansive suprasellar lesion. Cerebral angiography showed a saccular aneurysm of the anterior communicating complex. The patient underwent a surgical procedure for microsurgical clipping of the aneurysm and partial resection of the pituitary tumour. We have also included a brief review of the literature on this subject.


Assuntos
Adenoma/complicações , Aneurisma Roto/complicações , Aneurisma Intracraniano/complicações , Neoplasias Hipofisárias/complicações , Hemorragia Subaracnóidea/etiologia , Adenoma/diagnóstico por imagem , Adenoma/cirurgia , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/cirurgia , Cegueira/etiologia , Confusão/etiologia , Transtornos da Cefaleia Primários/etiologia , Hemodinâmica , Humanos , Hipofisectomia/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Recidiva Local de Neoplasia/complicações , Recidiva Local de Neoplasia/cirurgia , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Complicações Pós-Operatórias , Reoperação , Ruptura Espontânea , Estresse Mecânico , Hemorragia Subaracnóidea/diagnóstico por imagem , Tomografia Computadorizada por Raios X
10.
Appl Microbiol Biotechnol ; 97(12): 5635-43, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23649352

RESUMO

Molecular hydrogen (H2) is an ideal fuel characterized by high enthalpy change and lack of greenhouse effects. This biofuel can be released by microalgae via reduction of protons to molecular hydrogen catalyzed by hydrogenases. The main competitor for the reducing power required by the hydrogenases is the Calvin cycle, and rubisco plays a key role therein. Engineered Chlamydomonas with reduced rubisco levels, activity and stability was used as the basis of this research effort aimed at increasing hydrogen production. Biochemical monitoring in such metabolically engineered mutant cells proceeded in Tris/acetate/phosphate culture medium with S-depletion or repletion, both under hypoxia. Photosynthetic activity, maximum photochemical efficiency, chlorophyll and protein levels were all measured. In addition, expression of rubisco, hydrogenase, D1 and Lhcb were investigated, and H2 was quantified. At the beginning of the experiments, rubisco increased followed by intense degradation. Lhcb proteins exhibited monomeric isoforms during the first 24 to 48 h, and D1 displayed sensitivity under S-depletion. Rubisco mutants exhibited a significant decrease in O2 evolution compared with the control. Although the S-depleted medium was much more suitable than its complete counterpart for H2 production, hydrogen release was observed also in sealed S-repleted cultures of rubisco mutated cells under low-moderate light conditions. In particular, the rubisco mutant Y67A accounted for 10-15-fold higher hydrogen production than the wild type under the same conditions and also displayed divergent metabolic parameters. These results indicate that rubisco is a promising target for improving hydrogen production rates in engineered microalgae.


Assuntos
Chlamydomonas reinhardtii/enzimologia , Chlamydomonas reinhardtii/metabolismo , Hidrogênio/metabolismo , Fotossíntese , Ribulose-Bifosfato Carboxilase/metabolismo , Anaerobiose , Chlamydomonas reinhardtii/genética , Meios de Cultura/química , Engenharia Metabólica , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutação de Sentido Incorreto , Ribulose-Bifosfato Carboxilase/genética
11.
Braz J Biol ; 83: e274032, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37937626

RESUMO

The rubber tree (Hevea brasiliensis (Willd. ex A.Juss.) Müll.Arg.), a native Amazonian species, is responsible for more than 50 thousand products and stands out as the world's main source of natural rubber. Commercial production is carried out by grafting, however, the technique has gaps in terms of time and quality for seedling production. Vegetative production via cuttings is an alternative, however, the species is difficult to root. Thus, the study tested the rooting induction, through a chemical method, with the hormonal regulator indolbutyric acid (IBA) of 5000 ppm, and a mechanical method, with the strangulation of stems, and the interaction between the methods, to analyze the survival and sprouting of rubber tree (Hevea brasiliensis) cuttings, as well as verifying the efficiency of breaking the sclerenchyma ring by strangulation. A randomized block design was used, with four treatments (control, with strangulation, with IBA, strangulation x IBA) distributed in six blocks with 36 cuttings. Data were submitted to ANOVA test and Tukey's post-test (p>0.05). The results obtained 12.5% of live cuttings, without rooting, during 68 days, being the combination of strangulation and IBA with greater survival and sprouting. No breakage of the sclerenchyma ring was observed by histological analysis. The data indicate strategic gains in combining chemical and mechanical techniques for species of difficult rooting in vegetative propagation, however, the test was not enough to affirm an answer in relation to each technique, the deepening of the technique on the behavior of the species remains the biggest challenge.


Assuntos
Hevea , Reprodução
12.
Braz J Biol ; 83: e268716, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37042910

RESUMO

Pre-emergent herbicides can contribute to the control of weed competition in direct seeding restoration, however it is necessary to evaluate their effects on seeds of native tropical forest species. The aim of the study was to assess the potential impact of the herbicide indaziflam on the germination of 17 forest species. For this, a dosage of 180 mL of the product in 200L of water was compared to the control without herbicide. The degree of sensitivity of each species was calculated by a ratio between the percentage of germination with herbicide (GH) and the control without herbicide (GC) classifying them as: extremely sensitive (ES= (GH/GC) <0.25), sensitive (S=0.25< (GH/GC) <0.50), low sensitivity (LS=0.50< (GH/GC) <0.75), indifferent (I=0.75< (GH/GC) <1.0) and potentiated (P= (GH/GC) >1). The herbicide promoted a significant reduction in mean germination in 35% (n=6) of the species and 59% (n = 10) were sensitive or extremely sensitive to indaziflam, and only three did not germinate. On the other hand, 29.4% (n=5) showed low sensitivity or indifference to the herbicide, while seed germination was slightly increased by indaziflam to 11.7% (n=2). Pre-emergent indaziflam can be recommended in direct seeding restoration, as only 17.6% (n=3) of the species were inhibited by pre-emergent. However, the effect of indaziflam varies by species and requires further studies to support large-scale use in direct seeding.


Assuntos
Germinação , Herbicidas , Sementes , Herbicidas/farmacologia , Florestas
13.
Food Chem ; 134(3): 1337-42, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25005951

RESUMO

A growth trial with Senegalese Sole (Solea senegalensis Kaup, 1858) juveniles fed with diets containing increasing replacement levels of fishmeal by mixtures of plant protein sources was conducted over 12 weeks. Total fat contents of muscle, liver, viscera, skin, fins and head tissues were determined, as well as fatty acid profiles of muscle and liver (GC-FID analysis). Liver was the preferential local for fat deposition (5.5-10.8% of fat) followed by fins (3.4-6.7% fat). Increasing levels of plant protein in the diets seems to be related to increased levels of total lipids in the liver. Sole muscle is lean (2.4-4.0% fat), with total lipids being similar among treatments. Liver fatty acid profile varied significantly among treatments. Plant protein diets induced increased levels of C16:1 and C18:2 n-6 and a decrease in ARA and EPA levels. Muscle fatty acid profile also evidenced increasing levels of C18:2 n-6, while ARA and DHA remained similar among treatments. Substitution of fishmeal by plant protein is hence possible without major differences on the lipid content and fatty acid profile of the main edible portion of the fish - the muscle.


Assuntos
Ração Animal , Ácidos Graxos/análise , Linguados/metabolismo , Lipídeos/análise , Proteínas de Plantas/metabolismo , Animais , Animais Recém-Nascidos , Peso Corporal , Linguados/crescimento & desenvolvimento , Músculos/metabolismo
14.
Braz J Biol ; 82: e262017, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36197367

RESUMO

The aim of the current study is to evaluate gene expression patterns of LH (lhr) and estrogen (er) receptors and plasma steroid levels during testicular development in Genyatremus luteus. Males were histologically classified as immature (n=7), maturing (n=7) and mature (n=7), based on the cellular structure of their testes. Plasma 11-KT concentration recorded peak at the final maturation stage. The highest plasma 17α-OHP concentrations were observed at the immature stage; they decreased at the maturation and mature stages. On the other hand, 17ß-estradiol (E2) recorded higher concentrations at the maturation stage. Er expression has significantly increased along the maturational development of animals' testes. The mRNA observed for the LH receptor has decreased from immature to maturing stage; it presented expression peak at the mature stage. There was high association between receptor gene expression and plasma steroid levels, mainly E2. The current study was the first to feature different reproductive maturation stages in male G. luteus specimens, based on cellular, endocrine and molecular aspects. In addition, it has shown that the gene expression profile for er and lhr receptors, as well as plasma 11-KT and E2 concentrations, are directly linked to testicular maturation, although they are not necessarily associated with the gonadosomatic index.


Assuntos
Perciformes , Receptores do LH , Animais , Estradiol , Estrogênios , Peixes , Expressão Gênica , Hormônios Esteroides Gonadais , Masculino , Perciformes/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores do LH/genética
15.
Heredity (Edinb) ; 106(1): 134-45, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20372183

RESUMO

Over the past century, the Brazilian Atlantic forest has been reduced to small, isolated fragments of forest. Reproductive isolation theories predict a loss of genetic diversity and increases in inbreeding and spatial genetic structure (SGS) in such populations. We analysed eight microsatellite loci to investigate the pollen and seed dispersal patterns, genetic diversity, inbreeding and SGS of the tropical tree Copaifera langsdorffii in a small (4.8 ha), isolated population. All 112 adult trees and 128 seedlings found in the stand were sampled, mapped and genotyped. Seedlings had significantly lower levels of genetic diversity (A=16.5±0.45, mean±95% s.e.; H(e)=0.838±0.006) than did adult trees (A=23.2±0.81; H(e)=0.893±0.030). Parentage analysis did not indicate any seed immigration (m(seeds)=0) and the pollen immigration rate was very low (m(pollen)=0.047). The average distance of realized pollen dispersal within the stand was 94 m, with 81% of the pollen travelling <150 m. A significant negative correlation was found between the frequency and distance of pollen dispersal (r=-0.79, P<0.01), indicating that short-distance pollinations were more frequent. A significant SGS for both adults (∼50 m) and seedlings (∼20 m) was also found, indicating that most of the seeds were dispersed over short distances. The results suggested that the spatial isolation of populations by habitat fragmentation can restrict seed and pollen gene flow, increase SGS and affect the genetic diversity of future generations.


Assuntos
Fabaceae/genética , Fluxo Gênico , Variação Genética , Pólen/genética , Sementes/genética , Árvores/genética , Brasil , População , Plântula/genética , Plântula/fisiologia
16.
J Anim Physiol Anim Nutr (Berl) ; 95(4): 456-60, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21039934

RESUMO

Condensed tannins (CT) from grape seeds (Vitis vinifera L.) were added to complex the protein fraction of Lupinus angustifolius seeds. Three CT/protein ratios were used: 96 mg/g (T(1)), 180 mg/g (T(2)) and 0 mg/g (T(0)). The CP losses in the rumen were assessed by the nylon-bag technique and CP intestinal digestibility (CPID) was estimated using an in vitro assay applying a three-step procedure: samples were subject to rumen degradation (in situ, 16 h) and the remaining residues were subject to the digestive enzymes of the abomasum and pancreas in vitro. A positive effect (p < 0.05) of the level of CT on the immediately soluble faction a and the insoluble degradable fraction b was observed between T(0) and T(2) . In the presence of CT the rumen degradation rate was reduced (p < 0.05) from 0.0763/h (T(0)) to 0.0443/h (T(2)). The application of CT showed a reduction (around 10% for T(1)) of effective rumen CP degradability. The CPID did not seem to be affected (p > 0.05) by the presence of CT. These findings suggest that the use of grape seed CT might have the potential to improve the efficiency of utilisation of the protein fraction from lupin seeds.


Assuntos
Digestão/efeitos dos fármacos , Lupinus/química , Proantocianidinas/farmacologia , Sementes/química , Ovinos/fisiologia , Vitis/química , Animais , Intestinos/fisiologia , Masculino , Proteínas de Plantas/metabolismo , Proantocianidinas/química , Rúmen/efeitos dos fármacos , Rúmen/fisiologia , Fatores de Tempo
17.
Osteoarthr Cartil Open ; 3(1): 100137, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36475075

RESUMO

Objective: The primary aim was to quantify the improvements on function and pain of patients with knee osteoarthritis (KOA), short education and low income by a two-day self-management program. Secondary aims were verifying if the program improves clinically relevant measures of weight and strength. Design: A prospective randomized clinical trial was conducted in a tertiary hospital in Brazil with 191 patients with Kellgren & Lawrence grades II and III KOA who were allocated to two groups: control (usual care- CG) and intervention (usual care and two days of an OA self-management program with a multiprofessional team - IG). Western Ontario and McMaster Universities Index (WOMAC), weight, body mass index (BMI), Timed up and go (TUG) and five Times Sit to Stand Test (FTSST) were assessed at baseline, six, 12 and 24 months. Results: Groups were similar at baseline (p â€‹> â€‹0.05). Both groups exhibited improved WOMAC total and subsets scores throughout the study (p â€‹< â€‹0.001). However, only IG improved WOMAC total and subsets in all follow-ups above 20% (minimally clinically important difference), with differences in WOMAC pain, function and total scores (p â€‹= â€‹0.001, p â€‹< â€‹0.001, and p â€‹< â€‹0.001, respectively) and best effect sizes at 1 year (0.355, 0.651 and 0.770, respectively). IG group lost weight (p â€‹< â€‹0.001) and BMI (p â€‹< â€‹0.01). Both groups exhibited improvements in TUG and FTSST (p â€‹< â€‹0.001) that remained in all evaluations. FTSST results favored the IG, p â€‹= â€‹0.032. Conclusions: An educational program to patients with KOA, short schooling and low income improves clinically important measures of pain and function.

18.
Sci Rep ; 11(1): 4400, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33623067

RESUMO

Biomass burning in the Brazilian Amazon is modulated by climate factors, such as droughts, and by human factors, such as deforestation, and land management activities. The increase in forest fires during drought years has led to the hypothesis that fire activity decoupled from deforestation during the twenty-first century. However, assessment of the hypothesis relied on an incorrect active fire dataset, which led to an underestimation of the decreasing trend in fire activity and to an inflated rank for year 2015 in terms of active fire counts. The recent correction of that database warrants a reassessment of the relationships between deforestation and fire. Contrasting with earlier findings, we show that the exacerbating effect of drought on fire season severity did not increase from 2003 to 2015 and that the record-breaking dry conditions of 2015 had the least impact on fire season of all twenty-first century severe droughts. Overall, our results for the same period used in the study that originated the fire-deforestation decoupling hypothesis (2003-2015) show that decoupling was clearly weaker than initially proposed. Extension of the study period up to 2019, and novel analysis of trends in fire types and fire intensity strengthened this conclusion. Therefore, the role of deforestation as a driver of fire activity in the region should not be underestimated and must be taken into account when implementing measures to protect the Amazon forest.

19.
Int J Cardiol Heart Vasc ; 35: 100846, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34386574

RESUMO

Background Coronary heart disease has multiple risk factors, including air pollution. Numerous pathophysiological mechanisms have been identified with increasing levels of air pollution, mainly with ozone (O3), nitrogen dioxide (NO2), sulphur dioxide (SO2), particulate matter (PM10), fine particulate matter (PM2.5) and carbon monoxide (CO). In Mexico, the pollution level is reported using an air quality index called IMECA. Methods All patients with STEMI admitted at Hospital Español were collected between 2012 and 2019 (N = 348). We conducted a retrospective analysis using the air pollution exposure at the time of each event (lag0), the previous 24 h (lag1), 48 h (lag2), 72 h (lag3) and 5-day cumulative lag. The level of air pollution was analyzed independently using IMECA and particle concentrations. The data was divided in two groups: days with one of more STEMI's (MI group) and days free of events (Control group), using ANCOVA to evaluate the difference between means of both groups taking into account confounders. Results: For days with one or more cardiovascular event, a significant increase in SO2 was observed at lag1; similar increase was found in CO, PM2.5, SO2 at lag2. For the 5-day cumulative lag, SO2 and PM2.5 showed a significant increase. No differences were found using the IMECA levels in both groups. Conclusions: The elevated concentrations levels of CO, SO2 and PM2.5 showed significant association with STEMI at different time points before the event. Ozone, PM10 and NO2 showed no difference between groups. IMECA levels showed no association with STEMI in our study.

20.
Eur Phys J E Soft Matter ; 29(2): 245-51, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19551419

RESUMO

This paper studies energy localization conditions in lattices of the type proposed by Peyrard and Bishop. Homogeneous and inhomogeneous lattices are analyzed and the role of interfaces in the latter is emphasized. Simulations allowed us to identify critical energy values for the existence of localization. After a certain energy value, it is possible to observe the loss of energy localization along the chain.


Assuntos
Biopolímeros/química , Pareamento de Bases , DNA/química , Análise de Fourier , Modelos Moleculares , Termodinâmica
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