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1.
Nature ; 528(7580): 119-22, 2015 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-26595275

RESUMO

Drought threatens tropical rainforests over seasonal to decadal timescales, but the drivers of tree mortality following drought remain poorly understood. It has been suggested that reduced availability of non-structural carbohydrates (NSC) critically increases mortality risk through insufficient carbon supply to metabolism ('carbon starvation'). However, little is known about how NSC stores are affected by drought, especially over the long term, and whether they are more important than hydraulic processes in determining drought-induced mortality. Using data from the world's longest-running experimental drought study in tropical rainforest (in the Brazilian Amazon), we test whether carbon starvation or deterioration of the water-conducting pathways from soil to leaf trigger tree mortality. Biomass loss from mortality in the experimentally droughted forest increased substantially after >10 years of reduced soil moisture availability. The mortality signal was dominated by the death of large trees, which were at a much greater risk of hydraulic deterioration than smaller trees. However, we find no evidence that the droughted trees suffered carbon starvation, as their NSC concentrations were similar to those of non-droughted trees, and growth rates did not decline in either living or dying trees. Our results indicate that hydraulics, rather than carbon starvation, triggers tree death from drought in tropical rainforest.


Assuntos
Carbono/metabolismo , Secas , Floresta Úmida , Árvores/metabolismo , Clima Tropical , Água/metabolismo , Biomassa , Tamanho Corporal , Brasil , Metabolismo dos Carboidratos , Folhas de Planta/metabolismo , Caules de Planta/metabolismo , Estações do Ano , Solo/química , Árvores/crescimento & desenvolvimento , Xilema/metabolismo
2.
Med Vet Entomol ; 33(3): 397-406, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30887540

RESUMO

New species of insect-specific viruses (ISV) have been reported worldwide. In the present study, the complete genome of Culex flavivirus (CxFV) and partial sequences of other ISVs in Culex quinquefasciatus Say 1823 females (n = 3425) sampled in 200 urban areas census tracts of Cuiaba, state of Mato Grosso, were identified via reverse transcriptase-polymerase chain reaction for a NS5 region of flaviviruses, nucleotide and high-throughput sequencing, and viral isolation in C6/36 cells. CxFV was detected in 16 of 403 mosquito pools; sequences found in the study presented a high similarity with isolates from São Paulo, Brazil and other countries in Latin American that belong to genotype II, supporting the geographical influence on CxFV evolution. The monthly maximum likelihood estimation for CxFV ranged from 1.81 to 9.94 per 1000 mosquitoes. In addition to the CxFV complete genome, one pool contained an ORF1 sequence (756 bp) that belongs to a novel Negevirus from the Sandewavirus supergroup most similar to the Santana virus (77.1%) and another pool presented an RNA-dependent RNA polymerase sequence (1081 bp) of a novel Rhabdovirus most similar to Wuhan mosquito virus 9 (44%). After three passages in C6/36 cells, only CxFV was isolated from these co-infected pools. The importance of ISVs relies on their possible ability to interfere with arbovirus replication in competent vectors.


Assuntos
Culex/virologia , Flavivirus/genética , Genoma Viral , Animais , Brasil , Feminino , Flavivirus/classificação , Flavivirus/isolamento & purificação , Genótipo , Filogenia
3.
Neuroradiology ; 58(6): 585-594, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26909692

RESUMO

INTRODUCTION: Intracranial arteriovenous malformations (AVMs) are the most frequent cause of hemorrhagic strokes in the pediatric population. The study aim was to retrospectively assess the safety and efficacy of Onyx embolization with the intention to cure AVMs in a pediatric population. METHODS: A retrospective analysis of all patients (<18 years) who underwent endovascular embolization using Onyx at our institution was conducted. The primary endpoint was the composite complete angiographic occlusion of AVM immediately after the last embolization session that had no procedure-related complication requiring emergency surgery. Secondary endpoints were angiographic occlusion rates, procedure-related complications, and clinical outcomes after treatment and at the 6-month follow-up RESULTS: Twenty-three patients (mean age, 11.7 years) underwent a total of 45 embolization sessions. The median Spetzler-Martin grade was 3 (range 1 to 4). The primary endpoint was achieved in 19 patients (82.6 %). Complete angiographic occlusion of the AVM was obtained in 21 patients (91.3 %) immediately after embolization and at the 6-month follow-up. Embolization-related complications were observed in three patients (13 %). None of the complications resulted in permanent functional disability or death. In two patients (8.7 %), the AVM could not be completely occluded by embolization alone and the patients were referred to radiosurgery and microsurgery, respectively. CONCLUSION: Onyx embolization of AVM in pediatric patients with the intention to cure resulted in high occlusion rates without increasing neurological disability or death. The development of new embolization techniques and devices seems to improve the safety of Onyx embolization.


Assuntos
Dimetil Sulfóxido/uso terapêutico , Embolização Terapêutica/métodos , Hemostáticos/uso terapêutico , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/terapia , Polivinil/uso terapêutico , Adolescente , Angiografia Cerebral/métodos , Criança , Pré-Escolar , Angiografia por Tomografia Computadorizada/métodos , Dimetil Sulfóxido/efeitos adversos , Embolização Terapêutica/efeitos adversos , Feminino , Hemostáticos/efeitos adversos , Humanos , Lactente , Masculino , Polivinil/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
4.
Clin Oral Investig ; 20(1): 133-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25976838

RESUMO

OBJECTIVES: The aims of this study were to compare caries incidence and progression on sound occlusal surfaces and on surfaces presenting inactive enamel lesions in children and adolescents over 1 year and to estimate the risk of caries incidence and progression on these surfaces. METHODS: This prospective cohort study followed 200 7-15-year-old caries-inactive schoolchildren over 1 year. Stage of eruption, occlusal plaque, and occlusal caries were recorded on permanent molars. Statistical analysis was performed using generalized estimating equations with a logistic link function. RESULTS: Twenty-two children (11 %) presented "caries progression" (at least one active lesion on molar teeth). At site level, no difference was observed in caries incidence and progression between sites classified either sound (2.6 %) or with inactive enamel lesion (3.9 %) at the baseline examination (χ (2) test, p = 0.48). Adjusted for plaque, stage of eruption, type of molar and dental arch, inactive enamel lesions presented a similar risk for caries progression than sound occlusal surfaces (OR = 0.98, 95 % CI = 0.40-2.38). CONCLUSION: Within the limitations of this study, no difference was observed in caries incidence, progression, and risk on sound occlusal sites in comparison with sites presenting inactive enamel lesions. CLINICAL RELEVANCE: Occlusal surfaces harboring inactive caries lesions did not require additional attention than the one normally given to sound occlusal surfaces over a 1-year period.


Assuntos
Cárie Dentária/patologia , Esmalte Dentário/patologia , Adolescente , Brasil/epidemiologia , Criança , Índice CPO , Cárie Dentária/epidemiologia , Índice de Placa Dentária , Progressão da Doença , Feminino , Humanos , Incidência , Masculino , Dente Molar , Estudos Prospectivos , Fatores de Risco
5.
Clin Oral Investig ; 19(2): 565-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25467237

RESUMO

OBJECTIVE: This study aimed to evaluate the association between two visual criteria in assessing non-cavitated caries lesion activity on occlusal surfaces of permanent molars. MATERIALS AND METHODS: Thirty-nine patients with at least one permanent molar with non-cavitated caries lesion on the occlusal surface were selected. Molars were assessed according to their activity status following two criteria: ICDAS-LAA and a qualitative criterion based on clinical characteristics. RESULTS: The results showed that the LAA criterion seems to overestimate caries activity. A weak association between both criteria in assessing caries lesion activity and low specificity for ICDAS-LAA was observed. CONCLUSIONS: The ICDAS-LAA criterion is not suitable to assess non-cavitated caries lesion activity on occlusal surfaces of permanent molars because it assesses the lesions to be active more frequently than the qualitative criterion. CLINICAL RELEVANCE: The determination of caries lesion activity is a key decision point in the treatment of caries disease. This study discusses the best option to assess the activity of non-cavitated occlusal caries lesions.


Assuntos
Cárie Dentária/patologia , Dente Molar/patologia , Adolescente , Criança , Feminino , Humanos , Masculino
6.
Eur J Dent Educ ; 19(4): 235-41, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25495379

RESUMO

AIM: This study aimed to evaluate the effect of a digital learning tool on undergraduate dental students' performance in detecting dental caries using ICDAS. METHODS: An experimental digital learning tool (DLT) was created using digital photographs of sound and carious teeth. Thirty-nine students were divided into three groups (n = 13) and each assessed 12 randomly allocated patients before and after learning strategies: G1, ICDAS e-learning program; G2, ICDAS e-learning program plus DLT; G3, no learning strategy. Students (n = 32) reassessed patients 2 weeks after training. RESULTS: Comparing before and after the learning strategies, any difference in the values of specificity and area under the ROC curve for all groups was found. Sensitivity was statistically significantly higher for G1 and G2. Comparing the groups, G2 showed a significant increase in sensitivity at the D2 and D3 thresholds. Spearman's correlations with the gold standard before and after the learning strategy were 0.60 and 0.61 for G1, 0.57 and 0.63 for G2, and 0.54 and 0.54 for G3, respectively. The Wilcoxon test showed a statistically significant difference between the values obtained before and after learning strategies for G1 and G2. CONCLUSIONS: Use of the DLT after the ICDAS e-learning program tended to increase the sensitivity of ICDAS used by undergraduate dental students. The DLT appeared to improve dental students' ability to use ICDAS.


Assuntos
Instrução por Computador , Cárie Dentária/diagnóstico , Diagnóstico por Computador , Educação em Odontologia , Educação de Graduação em Medicina , Estudantes de Odontologia , Criança , Instrução por Computador/métodos , Instrução por Computador/normas , Diagnóstico por Computador/métodos , Diagnóstico por Computador/normas , Feminino , Humanos , Masculino , Curva ROC , Reprodutibilidade dos Testes , Software , Navegador
7.
Oecologia ; 176(2): 345-55, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25135179

RESUMO

In old, phosphorus (P)-impoverished habitats, root specializations such as cluster roots efficiently mobilize and acquire P by releasing large amounts of carboxylates in the rhizosphere. These specialized roots are rarely mycorrhizal. We investigated whether Discocactus placentiformis (Cactaceae), a common species in nutrient-poor campos rupestres over white sands, operates in the same way as other root specializations. Discocactus placentiformis showed no mycorrhizal colonization, but exhibited a sand-binding root specialization with rhizosheath formation. We first provide circumstantial evidence for carboxylate exudation in field material, based on its very high shoot manganese (Mn) concentrations, and then firm evidence, based on exudate analysis. We identified predominantly oxalic acid, but also malic, citric, lactic, succinic, fumaric, and malonic acids. When grown in nutrient solution with P concentrations ranging from 0 to 100 µM, we observed an increase in total carboxylate exudation with decreasing P supply, showing that P deficiency stimulated carboxylate release. Additionally, we tested P solubilization by citric, malic and oxalic acids, and found that they solubilized P from the strongly P-sorbing soil in its native habitat, when the acids were added in combination and in relatively low concentrations. We conclude that the sand-binding root specialization in this nonmycorrhizal cactus functions similar to that of cluster roots, which efficiently enhance P acquisition in other habitats with very low P availability.


Assuntos
Cactaceae/química , Fósforo/química , Exsudatos de Plantas/química , Raízes de Plantas/química , Solo/química , Brasil , Ácidos Carboxílicos/química , Micorrizas , Raízes de Plantas/anatomia & histologia , Rizosfera
8.
Caries Res ; 47(3): 177-82, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23221986

RESUMO

The aim of this study was to estimate the independent effects of biofilm accumulation and eruption stage on the occurrence of active caries lesions on occlusal surfaces of permanent molars. The sample consisted of 298 schoolchildren (6-15 years) who were examined by a calibrated examiner at a dental unit, using artificial light, a dental mirror and a WHO probe. The occurrence of visible biofilm on occlusal surfaces and the eruption stage of each permanent molar were recorded. After professional prophylaxis and air drying, the occlusal surfaces were classified as sound, caries-inactive or caries-active. To evaluate the association of eruption stage and biofilm accumulation with active caries lesions, a logistic regression model was used. Since data were clustered, odds ratios were obtained using generalized estimating equations with a logistic link function. 1,779 permanent molars were examined. All eruption stages were associated with active caries lesions. After adjustment for biofilm accumulation and type of molar, molars with occlusal surfaces partially exposed to the oral cavity were 63.6 times more susceptible to caries activity than molars with full occlusion (95% CI = 22.0-183.7). After adjustment for eruption stage and type of molar, teeth with a high degree of biofilm accumulation were 14.5 times more susceptible to caries activity than those without visible biofilm accumulation (95% CI = 6.5-32.4). No association between active caries and hardly detectable biofilm was found in this population. The present study found that the eruption stage of permanent molars is strongly associated with active caries lesions, adjusted for biofilm accumulation and type of molar.


Assuntos
Cárie Dentária/microbiologia , Cárie Dentária/fisiopatologia , Dente Molar/fisiopatologia , Erupção Dentária , Adolescente , Biofilmes , Criança , Estudos Transversais , Cárie Dentária/patologia , Feminino , Humanos , Modelos Logísticos , Masculino , Dente Molar/crescimento & desenvolvimento , Dente Molar/microbiologia , Razão de Chances
9.
Int J Sports Med ; 34(5): 424-30, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23143705

RESUMO

The aim of this study was to determine the changes in physical performance and resting heart rate variability (HRV) in professional futsal players during the pre-season and in-season training periods. 11 athletes took part in the study (age=24.3±2.9 years; height=176.3±5.2 cm; weight=76.1±6.3 kg), and performed a repeated-sprint ability (RSA) test [6×40 m (20+20 m with a 180° change of direction) sprints separated by 20 s of passive recovery] and Yo-Yo intermittent recovery test level 1 (Yo-Yo IR1) at 3 different moments (M1=beginning of pre-season; M2=end of pre-season; M3=mid in-season). The HRV indices were assessed at the same moments. After the short pre-season (3-week), mean RSA time (RSAmean) (M1=7.43±0.2 s; M2=7.24±0.2 s; P=0.003), decrement in RSA performance (RSAdecrement) (M1=6.7±0.3%; M2=5.0±0.9%; P=0.001), and Yo-Yo IR1 distance (M1=1.244±298 m; M2=1.491±396 m; P=0.002) were significantly improved (P<0.05). During the in-season (i. e., M3), performance in Yo-Yo IR1 and RSAmean were maintained. In contrast, RSAbest (M2=6.89±0.2 to M3=6.69±0.3; P=0.001) was improved and RSAdecrement (M2=5.0±0.9% to M3=6.6±0.9%; P=0.001) was impaired. At M2, there was an increase in HRV vagal-related indices compared with M1 that was maintained at M3. In conclusion, after a short pre-season, futsal players improved their RSA and Yo-Yo IR1 performance with concomitant improvements in HRV. These indices were maintained during the in-season period while RSAbest was improved and RSAdecrement impaired. Frequent monitoring of these performances and HRV indices may assist with identification of individual training adaptations and/or early signs of maladaption.


Assuntos
Desempenho Atlético/fisiologia , Frequência Cardíaca/fisiologia , Corrida/fisiologia , Estações do Ano , Futebol/fisiologia , Adulto , Análise de Variância , Teste de Esforço , Humanos , Masculino , Adulto Jovem
10.
Genet Mol Res ; 12(3): 2341-50, 2013 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-23315871

RESUMO

The use of efficient breeding methods depends on knowledge of genetic control of traits to be improved. We estimated genetic parameters, selection gain, and genetic diversity in physic nut half-sib families, in order to provide information for breeding programs of this important biofuel species. The progeny test included 20 half-sib families in 4 blocks and 10 plants per plot. The mean progeny heritability values were: 50% for number of bunches, 47% for number of fruits, 35% for number of seeds, 6% for stem diameter, 26% for number of primary branches, 14% for number of secondary branches, 66% for plant height, and 25% for survival of the plants, demonstrating good potential for early selection in plant height, number of branches, and number of fruits per plant. In the analysis of genetic diversity, genotypes were divided into 4 groups. Genotypes 18, 19, 20, and 8 clustered together and presented the highest means for the vegetative and production. Lower means were observed in the 17, 12, 13, and 9 genotypes from the same group. We detected genetic variability in this population, with high heritability estimates and accuracy, demonstrating the possibility of obtaining genetic gains for vegetative characters and production at 24 months after planting.


Assuntos
Variação Genética , Jatropha/genética , Seleção Genética , Cruzamento , Jatropha/anatomia & histologia , Componentes Aéreos da Planta/anatomia & histologia , Característica Quantitativa Herdável
11.
Plant Biol (Stuttg) ; 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38059684

RESUMO

The concurrent impacts of multiple disturbances have the potential to modify ecosystem functioning by diminishing recovery capacity and resilience. Nevertheless, it remains uncertain how plant species from tropical communities respond to the cumulative effects of drought and fire. In this study, we evaluated the responses of six plant species from campos rupestres subjected to a mild drought followed by fire and tested if plants subjected to simulated drought show reductions in carbon uptake and depletion of non-structural carbohydrate (NSC) reserves, thus constraining their resprouting. We monitored monthly variations in leaf gas exchange and aboveground biomass over 18 months. Subsequently, an accidental fire occurred in the study area, leading us to collect samples of belowground structures for NSC analyses on the day of the burn. There were no differences in the frequency of resprouting between the above two conditions. Additionally, gas exchange in most species either remained stable or increased after the fire. Drought had no adverse effects on NSC reserves in the belowground structures and may have contributed to species resprouting after fire. The impact of drought pre-conditions on post-fire aboveground biomass was generally minor for most species, except Vellozia nivea, which displayed roughly a 5% reduction in biomass following the drought. Our findings highlight the remarkable resilience of campos rupestres species, even after enduring 18 months of reduced water availability and an unintended fire event. These species demonstrated the capacity to maintain their physiological functions and resprouting capacities after a fire event, underscoring their strong recovery potential.

12.
Plant Biol (Stuttg) ; 25(7): 1171-1185, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37703535

RESUMO

The increasing frequency of global change-type droughts has created a need for fast, accurate and widely applicable techniques for estimating xylem embolism resistance to improve forecasts of future forest changes. We used data from 12 diffuse-porous temperate tree species covering a wide range of xylem safety to compare the pneumatic and flow-centrifuge method, two rapid methods used for constructing xylem vulnerability curves. We evaluated the agreement between parameters estimated with both methods and the sensitivity of pneumatic measurements to the duration of air discharge (AD) measurements. There was close agreement between xylem water potentials at 50% air discharged (PAD), estimated with the Pneumatron, and 50% loss of hydraulic conductivity (PLC), estimated with the flow-centrifuge method (mean signed deviation: 0.12 MPa, Pearson correlation: 0.96 after 15 s of gas extraction). However, the relationship between the estimated slopes was more variable, resulting in lower agreement in the xylem water potential at 12% and 88% PAD/PLC. The agreement between the two methods was not affected by species-specific vessel length distributions. All pneumatic parameters were sensitive to AD time. Overall agreement was highest at relatively short AD times, with an optimum at 16 s. Our results highlight the value of the Pneumatron as an easy and reliable tool to estimate 50% embolism thresholds for a wide range of diffuse-porous temperate angiosperms. Further, our study provides a set of useful metrics for methodological comparisons of vulnerability curves in terms of systematic and random deviations, as well as overall agreement.


Assuntos
Embolia , Árvores , Porosidade , Xilema , Água , Secas
13.
Sci Total Environ ; 876: 162600, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-36871717

RESUMO

Tropical ecosystems are central to the global focus on halting and reversing habitat destruction as a means of mitigating carbon emissions. Brazil has been highlighted as a vital part of global climate agreements because, whilst ongoing land-use change causes it to be the world's fifth biggest greenhouse gas emitting country, it also has one of the greatest potentials to implement ecosystem restoration. Global carbon markets provide the opportunity of a financially viable way to implement restoration projects at scale. However, except for rainforests, the restoration potential of many major tropical biomes is not widely recognised, with the result that carbon sequestration potential may be squandered. We synthesize data on land availability, land degradation status, restoration costs, area of native vegetation remaining, carbon storage potential and carbon market prices for 5475 municipalities across Brazil's major biomes, including the savannas and tropical dry forests. Using a modelling analysis, we determine how fast restoration could be implemented across these biomes within existing carbon markets. We argue that even with a sole focus on carbon, we must restore other tropical biomes, as well as rainforests, to effectively increase benefits. The inclusion of dry forests and savannas doubles the area which could be restored in a financially viable manner, increasing the potential CO2e sequestered >40 % above that offered by rainforests alone. Importantly, we show that in the short-term avoiding emissions through conservation will be necessary for Brazil to achieve it's 2030 climate goal, because it can sequester 1.5 to 4.3 Pg of CO2e by 2030, relative to 0.127 Pg CO2e from restoration. However, in the longer term, restoration across all biomes in Brazil could draw down between 3.9 and 9.8 Pg of CO2e from the atmosphere by 2050 and 2080.


Assuntos
Sequestro de Carbono , Ecossistema , Brasil , Análise Custo-Benefício , Florestas , Carbono , Conservação dos Recursos Naturais
14.
Int J Sports Med ; 33(10): 813-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22592542

RESUMO

We examined the effects of listening to music on attentional focus, rating of perceived exertion (RPE), pacing strategy and performance during a simulated 5-km running race. 15 participants performed 2 controlled trials to establish their best baseline time, followed by 2 counterbalanced experimental trials during which they listened to music during the first (M start) or the last (M finish) 1.5 km. The mean running velocity during the first 1.5 km was significantly higher in M start than in the fastest control condition (p<0.05), but there was no difference in velocity between conditions during the last 1.5 km (p>0.05). The faster first 1.5 m in M start was accompanied by a reduction in associative thoughts compared with the fastest control condition. There were no significant differences in RPE between conditions (p>0.05). These results suggest that listening to music at the beginning of a trial may draw the attentional focus away from internal sensations of fatigue to thoughts about the external environment. However, along with the reduction in associative thoughts and the increase in running velocity while listening to music, the RPE increased linearly and similarly under all conditions, suggesting that the change in velocity throughout the race may be to maintain the same rate of RPE increase.


Assuntos
Desempenho Atlético/psicologia , Música , Corrida/psicologia , Adulto , Atenção , Fadiga/psicologia , Humanos , MP3-Player , Masculino , Adulto Jovem
15.
Oper Dent ; 47(5): 476-480, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36026708

RESUMO

The aim of this paper is to present a case of masking of a hypoplastic lesion using the infiltrating resin technique, without use of drilling or any loss of tooth structure. A 22-year-old female patient complained of a noncarious white spot on the buccal surface of the upper right central incisor which affected the esthetics of her smile. Despite the tooth discoloration, the tooth structure was intact, with no depressions, cracks, or grooves. During the anamnesis, she reported that the white spot had been present since childhood. On the basis of the information provided by the patient and collected during intraoral clinical examination, it was determined that the stain was suggestive of enamel hypoplasia. The treatment proposed to the patient was the application of infiltrating resin to mask the hypoplasia on the surface of the tooth enamel without any loss of tooth structure. In this case, Icon infiltrating resin proved to be efficient in masking the hypoplastic lesion. The final appearance of the treated tooth was satisfactory, with homogeneity and gloss on the surface, which minimized the characteristics of an unpleasant smile.


Assuntos
Cárie Dentária , Hipoplasia do Esmalte Dentário , Clareamento Dental , Descoloração de Dente , Doenças Dentárias , Adulto , Criança , Cárie Dentária/patologia , Esmalte Dentário/patologia , Hipoplasia do Esmalte Dentário/tratamento farmacológico , Hipoplasia do Esmalte Dentário/patologia , Feminino , Humanos , Incisivo/cirurgia , Resinas Sintéticas/uso terapêutico , Clareamento Dental/métodos , Descoloração de Dente/terapia , Adulto Jovem
16.
Braz J Biol ; 84: e257402, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35081217

RESUMO

Visceral leishmaniasis (VL) is an infectious disease predominant in countries located in the tropics. The prediction of occurrence of infectious diseases through epidemiologic modeling has revealed to be an important tool in the understanding of its occurrence dynamic. The objective of this study was to develop a forecasting model for the incidence of VL in Maranhão using the Seasonal Autoregressive Integrated Moving Average model (SARIMA). We collected monthly data regarding VL cases from the National Disease Notification System (SINAN) corresponding to the period between 2001 and 2018. The Box-Jenkins method was applied in order to adjust a SARIMA prediction model for VL general incidence and by sex (male or female) for the period between January 2019 and December 2013. For 216 months of this time series, 10,431 cases of VL were notified in Maranhão, with an average of 579 cases per year. With regard to age range, there was a higher incidence among the pediatric public (0 to 14 years of age). There was a predominance in male cases, 6437 (61.71%). The Box-Pierce test figures for overall, male and female genders supported by the results of the Ljung-Box test suggest that the autocorrelations of residual values act as white noise. Regarding monthly occurrences in general and by gender, the SARIMA models (2,0,0) (2,0,0), (0,1,1) (0,1,1) and (0,1,1) (2, 0, 0) were the ones that mostly adjusted to the data respectively. The model SARIMA has proven to be an adequate tool for predicting and analyzing the trends in VL incidence in Maranhão. The time variation determination and its prediction are decisive in providing guidance in health measure intervention.


Assuntos
Leishmaniose Visceral , Adolescente , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Masculino , Modelos Estatísticos , Estações do Ano
17.
Tree Physiol ; 42(3): 537-556, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-34508606

RESUMO

Future climate change predictions for tropical forests highlight increased frequency and intensity of extreme drought events. However, it remains unclear whether large and small trees have differential strategies to tolerate drought due to the different niches they occupy. The future of tropical forests is ultimately dependent on the capacity of small trees (<10 cm in diameter) to adjust their hydraulic system to tolerate drought. To address this question, we evaluated whether the drought tolerance of neotropical small trees can adjust to experimental water stress and was different from tall trees. We measured multiple drought resistance-related hydraulic traits across nine common neotropical genera at the world's longest-running tropical forest throughfall-exclusion experiment and compared their responses with surviving large canopy trees. Small understorey trees in both the control and the throughfall-exclusion treatment had lower minimum stomatal conductance and maximum hydraulic leaf-specific conductivity relative to large trees of the same genera, as well as a greater hydraulic safety margin (HSM), percentage loss of conductivity and embolism resistance, demonstrating that they occupy a distinct hydraulic niche. Surprisingly, in response to the drought treatment, small trees increased specific hydraulic conductivity by 56.3% and leaf:sapwood area ratio by 45.6%. The greater HSM of small understorey trees relative to large canopy trees likely enabled them to adjust other aspects of their hydraulic systems to increase hydraulic conductivity and take advantage of increases in light availability in the understorey resulting from the drought-induced mortality of canopy trees. Our results demonstrate that differences in hydraulic strategies between small understorey and large canopy trees drive hydraulic niche segregation. Small understorey trees can adjust their hydraulic systems in response to changes in water and light availability, indicating that natural regeneration of tropical forests following long-term drought may be possible.


Assuntos
Secas , Árvores , Mudança Climática , Florestas , Folhas de Planta/fisiologia , Árvores/fisiologia
18.
J Appl Microbiol ; 110(1): 118-27, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20880215

RESUMO

AIMS: Glyphosate-resistant (GR) soybean production increases each year because of the efficacy of glyphosate for weed management. A new or 'second' generation of GR soybean (GR2) is now commercially available for farmers that is being promoted as higher yielding relative to the previous, 'first generation' (GR1) cultivars. Recent reports show that glyphosate affects the biology and ecology of rhizosphere micro-organisms in GR soybean that affect yield. The objective of this research was to evaluate the microbiological interactions in the rhizospheres of GR2 and GR1 soybean and the performance of the cultivars with different rates of glyphosate applied at different growth stages. METHODS AND RESULTS: A greenhouse study was conducted using GR1 and GR2 soybean cultivars grown in a silt loam soil. Glyphosate was applied at V2, V4 and V6 growth stages at three rates. Plants harvested at R1 growth stage had high root colonization by Fusarium spp.; reduced rhizosphere fluorescent pseudomonads, Mn-reducing bacteria, and indoleacetic acid-producing rhizobacteria; and reduced shoot and root biomass. CONCLUSIONS: Glyphosate applied to GR soybean, regardless of cultivar, negatively impacts the complex interactions of microbial groups, biochemical activity and root growth that can have subsequent detrimental effects on plant growth and productivity. SIGNIFICANCE AND IMPACT OF THE STUDY: The information presented here will be crucial in developing strategies to overcome the potential detrimental effects of glyphosate in GR cropping systems.


Assuntos
Glycine max/microbiologia , Glicina/análogos & derivados , Herbicidas/farmacologia , Rizosfera , Fusarium/crescimento & desenvolvimento , Glicina/farmacologia , Manganês/química , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Pseudomonas/crescimento & desenvolvimento , Microbiologia do Solo , Glycine max/efeitos dos fármacos , Glycine max/crescimento & desenvolvimento , Glifosato
19.
Braz J Biol ; 81(3): 557-565, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32876165

RESUMO

Cutaneous leishmaniasis (CL) is a neglected tropical disease with a wide distribution in the Americas. Brazil is an endemic country and present cases in all states. This study aimed to describe the occurrence, the underlying clinical and epidemiological factors, and the correlation of climatic variables with the frequency of reported CL cases in the municipality of Caxias, state of Maranhão, Brazil. This is a retrospective and descriptive epidemiological study based on data extracted from the Brazilian Information System of Diseases Notification, from 2007 to 2017. Maximum and minimum temperature, precipitation, and relative air humidity data were provided by the Brazilian National Institute of Meteorology. A total of 201 reported autochthonous CL cases were analyzed. The predominance of cases was observed in males (70.1%). The age range between 31 and 60 years old was the most affected, with 96 cases (47.9%). Of the total number of registered cases, 38.8% of the affected individuals were engaged in agriculture-related activities. The georeferenced distribution revealed the heterogeneity of disease occurrence, with cases concentrated in the Western and Southern regions of the municipality. An association was detected between relative air humidity (monthly mean) and the number of CL cases per month (p = 0.04). CL continues to be a concerning public health issue in Caxias. In this context, there is a pressing need to strengthen measures of prevention and control of the disease through the network of health services of the municipality, considering local and regional particularities.


Assuntos
Leishmaniose Cutânea , Adulto , Brasil/epidemiologia , Cidades , Meio Ambiente , Humanos , Leishmaniose Cutânea/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
20.
Inflamm Res ; 59(4): 245-54, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19757085

RESUMO

OBJECTIVES: To study and characterize the in vivo effect of the lectin from Luetzelburgia auriculata seed on acute inflammation models. METHODS: The lectin was purified from the crude saline extract by affinity chromatography on a guar-gum matrix. Native, heat-treated, and digested lectin was evaluated for anti-inflammatory activity by using peritonitis and paw edema models. The anti-inflammatory activity was characterized by intravital microscopy, nitric oxide production, and myeloperoxidase activity. RESULTS: The lectin exhibited anti-inflammatory activity (2 mg/kg) on both models, reducing local myeloperoxidase activity. Galactose or heat treatment (100 degrees C, 10 min) reduced anti-inflammatory action. Anti-inflammation involves the inhibition of adhesion and rolling of leukocytes along with augmentation of nitric oxide in serum. The lectin inhibited the edematogenic effect of histamine and prostaglandins (PGE2) but did not alter the chemoattractant effect of IL-8. CONCLUSIONS: The results indicate that this lectin is a potent anti-inflammatory molecule. Its effects engage diverse modulatory events.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Adesão Celular/efeitos dos fármacos , Dinoprostona/antagonistas & inibidores , Fabaceae/química , Antagonistas dos Receptores Histamínicos , Inflamação/tratamento farmacológico , Migração e Rolagem de Leucócitos/efeitos dos fármacos , Leucócitos/efeitos dos fármacos , Lectinas de Plantas/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Carragenina , Quimiotaxia de Leucócito/efeitos dos fármacos , Dinoprostona/farmacologia , Edema/induzido quimicamente , Edema/prevenção & controle , Eletroforese em Gel de Poliacrilamida , Galactose/metabolismo , Indicadores e Reagentes , Inflamação/enzimologia , Inflamação/patologia , Neutrófilos/efeitos dos fármacos , Óxido Nítrico/metabolismo , Peritonite/induzido quimicamente , Peritonite/tratamento farmacológico , Peroxidase/metabolismo , Lectinas de Plantas/química , Ratos , Ratos Wistar , Sementes/química
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