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1.
Neotrop Entomol ; 49(5): 745-757, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32445112

RESUMO

Interactions between different pest control methods can affect Integrated Pest Management efficiency. This study sought to evaluate (1) if Si accumulation is related to the level of constitutive resistance in sorghum genotypes, (2) the level of Si induces resistance by antibiosis in sorghum genotypes with different levels of constitutive resistance to Schizaphis graminum (Rondani) (reared individualized or in colonies), and (3) the fitness of Lysiphlebus testaceipes (Cresson) in aphids reared on Si-treated and untreated plants. Several experiments were conducted under greenhouse conditions, using sorghum genotypes with different levels of resistance grown in pots with or without the addition of Si to the soil. The susceptible (BR007B), moderately resistant (GB3B), and highly resistant (TX430XGR111) genotypes all absorbed more Si when it was added to the soil compared with when it was not amended. However, the final Si content of treated plants was not related to the level of constitutive resistance among treated genotypes. While Si soil application did reduce the fecundity of individualized aphids reared on the susceptible and moderately resistant sorghum plants, it did not reduce populational growth of aphid colonies, independent of the level of plant's constitutive resistance. Parasitoid (L. testaceipes) had higher weight when reared from aphids fed on plants with added Si. Sorghum × constitutive resistance × S. graminum interactions were affected by plant Si content only for individualized aphids but not for aphid colonies. Sorghum × S. graminum × L. testaceipes interactions suggest that Si can have, overall, a positive effect on the biological control of S. graminum.


Assuntos
Afídeos/crescimento & desenvolvimento , Controle Biológico de Vetores , Silício/administração & dosagem , Sorghum/genética , Vespas/fisiologia , Animais , Afídeos/parasitologia , Fertilizantes , Genótipo , Crescimento Demográfico , Solo/química
2.
Sci Rep ; 9(1): 17483, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31767886

RESUMO

Anisotropy of magnetic susceptibility (AMS) is regularly applied as a tool to infer structural analysis of deformation and flow in rocks, particularly, with low anisotropy. AMS integrates the magnetic signature of crystallographic and shape preferred orientation of all mineral grains present in the rock microstructure. Those preferred orientations result from multiple processes affecting the rock during its evolution, therefore the desirable AMS-strain relationship is not straightforward. Here we show that due to localization of deformation, AMS is indirectly dependent on the magnitude and character of deformation. In order to decipher the AMS-strain relationship, AMS studies should be accompanied by microstructural analyses combined with numerical modelling of magnetic fabric. A small-scale shear zone produced by single deformation event was studied. The resultant AMS fabric is "inverse" due to the presence of Fe-dolomite and controlled by calcite and dolomite crystallographic preferred orientations. The localized deformation resulted in the angular deviation between macroscopic and magnetic fabric in the shear zone, systematically increasing with increasing strain. This is a result of the presence of microstructural subfabrics of coarse porphyroclasts and fine-grained recrystallized matrix produced by localization.The localization of deformation is a multiscale and widespread process that should be considered whenever interpreting AMS in deformed rocks and regions.

3.
Braz J Med Biol Res ; 49(2): e4890, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26871969

RESUMO

The oxygen uptake efficiency slope (OUES) is a submaximal index incorporating cardiovascular, peripheral, and pulmonary factors that determine the ventilatory response to exercise. The purpose of this study was to evaluate the effects of continuous exercise training and interval exercise training on the OUES in patients with coronary artery disease. Thirty-five patients (59.3±1.8 years old; 28 men, 7 women) with coronary artery disease were randomly divided into two groups: continuous exercise training (n=18) and interval exercise training (n=17). All patients performed graded exercise tests with respiratory gas analysis before and 3 months after the exercise-training program to determine ventilatory anaerobic threshold (VAT), respiratory compensation point, and peak oxygen consumption (peak VO2). The OUES was assessed based on data from the second minute of exercise until exhaustion by calculating the slope of the linear relation between oxygen uptake and the logarithm of total ventilation. After the interventions, both groups showed increased aerobic fitness (P<0.05). In addition, both the continuous exercise and interval exercise training groups demonstrated an increase in OUES (P<0.05). Significant associations were observed in both groups: 1) continuous exercise training (OUES and peak VO2 r=0.57; OUES and VO2 VAT r=0.57); 2) interval exercise training (OUES and peak VO2 r=0.80; OUES and VO2 VAT r=0.67). Continuous and interval exercise training resulted in a similar increase in OUES among patients with coronary artery disease. These findings suggest that improvements in OUES among CAD patients after aerobic exercise training may be dependent on peripheral and central mechanisms.


Assuntos
Doença da Artéria Coronariana/metabolismo , Terapia por Exercício/métodos , Exercício Físico/fisiologia , Consumo de Oxigênio/fisiologia , Limiar Anaeróbio/fisiologia , Análise de Variância , Índice de Massa Corporal , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/reabilitação , Teste de Esforço/métodos , Feminino , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Condicionamento Físico Humano/métodos , Esforço Físico/fisiologia , Avaliação de Programas e Projetos de Saúde/estatística & dados numéricos , Função Ventricular Esquerda
4.
Braz. j. med. biol. res ; 49(2): e4890, 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951658

RESUMO

The oxygen uptake efficiency slope (OUES) is a submaximal index incorporating cardiovascular, peripheral, and pulmonary factors that determine the ventilatory response to exercise. The purpose of this study was to evaluate the effects of continuous exercise training and interval exercise training on the OUES in patients with coronary artery disease. Thirty-five patients (59.3±1.8 years old; 28 men, 7 women) with coronary artery disease were randomly divided into two groups: continuous exercise training (n=18) and interval exercise training (n=17). All patients performed graded exercise tests with respiratory gas analysis before and 3 months after the exercise-training program to determine ventilatory anaerobic threshold (VAT), respiratory compensation point, and peak oxygen consumption (peak VO2). The OUES was assessed based on data from the second minute of exercise until exhaustion by calculating the slope of the linear relation between oxygen uptake and the logarithm of total ventilation. After the interventions, both groups showed increased aerobic fitness (P<0.05). In addition, both the continuous exercise and interval exercise training groups demonstrated an increase in OUES (P<0.05). Significant associations were observed in both groups: 1) continuous exercise training (OUES and peak VO2 r=0.57; OUES and VO2 VAT r=0.57); 2) interval exercise training (OUES and peak VO2 r=0.80; OUES and VO2 VAT r=0.67). Continuous and interval exercise training resulted in a similar increase in OUES among patients with coronary artery disease. These findings suggest that improvements in OUES among CAD patients after aerobic exercise training may be dependent on peripheral and central mechanisms.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Doença da Artéria Coronariana/metabolismo , Exercício Físico/fisiologia , Terapia por Exercício/métodos , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/reabilitação , Limiar Anaeróbio/fisiologia , Avaliação de Programas e Projetos de Saúde/estatística & dados numéricos , Índice de Massa Corporal , Análise de Variância , Função Ventricular Esquerda , Teste de Esforço/métodos , Esforço Físico/fisiologia , Condicionamento Físico Humano/métodos , Hipertensão/fisiopatologia
5.
Genet Mol Res ; 14(4): 17416-25, 2015 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-26782383

RESUMO

Nearly 60% of Paracoccidioides lutzii genes encode products annotated as hypothetical or predicted proteins (HPs). In this study, we describe the global detection and functional inference of HPs, using computational methods based on sequence similarity, identification of targeting signals, presence of known protein domains, and use of the Gene Ontology functional classification scheme. Our analysis enabled a high-throughput characterization of predicted cellular localization and presence of protein domains, clustering HPs into different functional categories including metabolism, localization, cell cycle, response to stimulus, and signaling. To investigate P. lutzii HP expression profiles, we used data obtained from the expressed sequence tag database (dbEST). These analyses revealed 2364 HPs expressed in different situations, namely in mycelial and yeast forms, during the transition from mycelium to yeast, and under conditions mimicking infection. Based on this transcriptomic data, we performed a functional enrichment analysis according to the domains present in the HPs expressed in each condition. The most overrepresented functional domains were those involved in the regulation of gene expression, suggesting important and as yet undescribed roles for these HPs in the adaptation of P. lutzii to environmental conditions. In addition, the expression profiles of six randomly selected HPs were analyzed by quantitative real-time polymerase chain reaction in order to verify their expression in the complementary DNA libraries analyzed in this investigation. The approach used in this study should improve functional characterization of P. lutzii HPs.


Assuntos
Etiquetas de Sequências Expressas , Anotação de Sequência Molecular , Paracoccidioides/genética , Análise de Sequência de DNA , Regulação Fúngica da Expressão Gênica , Biblioteca Gênica , Micélio/genética
6.
Res Vet Sci ; 93(3): 1515-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22769738

RESUMO

The aim of this study was to investigate the presence of swine hepatitis E virus (HEV) from pigs of different production categories and from different pig farms in South Brazil. A total of 170 porcine faecal samples from breeder sows, boars, suckling piglets, weaned and growing pigs were collected from 14 pig farms. The faecal samples were screened by nested RT-PCR using primers targeting the ORF2 region of HEV genome. The samples that were positive from this screening were used in a nested RT-PCR targeting the ORF1 region. The screening detected HEV RNA in 62.5% of the pig farms and in 15.3% of the faecal samples. In 15 faecal samples, it was possible to amplify the HEV RNA with both the ORF1 and ORF2 regions. The phylogenetic analyses obtained for both ORFs confirmed that all of the Brazilian swine HEV isolates clustered with genotype 3b, the same genotype described previously in humans in Brazil.


Assuntos
Vírus da Hepatite E/genética , Hepatite E/veterinária , Doenças dos Suínos/virologia , Animais , Brasil/epidemiologia , Fezes/virologia , Feminino , Genótipo , Hepatite E/epidemiologia , Hepatite E/virologia , Masculino , Epidemiologia Molecular , Filogenia , Suínos , Doenças dos Suínos/epidemiologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-22243444

RESUMO

The increasing use of antimicrobial agents such as sulfonamides by the pig industry is of concern, since residues in both pork and its by-products, when derived from animals treated improperly, can endanger human health. The aim of this study was to establish the production conditions and to evaluate the homogeneity and the stability of sulfamethazine in porcine liver quality control material, produced 'in-house' for use in ring tests of the laboratory network of residues and contaminants of the Ministry of Agriculture, Livestock and Food Supply, Brazil. In the process of preparing the material, a FOSS blender was used, where the samples were ground to obtain a homogeneous mass, which was packed in polypropylene bottles. The material resulting from this process of homogenisation was sampled and analysed by LC/MS/MS. The analytical results were statistically evaluated by one-way ANOVA. According to statistical evaluation, the material produced was considered homogeneous, with 95% confidence. Stability tests were performed with the bottles stored under the specified storage conditions. They were randomly selected and analysed in duplicate by the same analytical method as the homogeneity study. The analytical results were statistically evaluated by the procedures for a stability check described in ISO 13528:2005, indicating that the material was unstable under the conditions of storage.


Assuntos
Anti-Infecciosos/análise , Contaminação de Alimentos/análise , Sulfametazina/análise , Animais , Anti-Infecciosos/normas , Brasil , Cromatografia Líquida , Resíduos de Drogas/análise , Resíduos de Drogas/normas , Contaminação de Alimentos/legislação & jurisprudência , Contaminação de Alimentos/prevenção & controle , Contaminação de Alimentos/estatística & dados numéricos , Inocuidade dos Alimentos , Humanos , Fígado/química , Carne/análise , Controle de Qualidade , Padrões de Referência , Sulfametazina/normas , Sus scrofa , Espectrometria de Massas em Tandem , Drogas Veterinárias/análise , Drogas Veterinárias/normas
8.
Neuroscience ; 200: 42-9, 2012 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-22067609

RESUMO

Iron accumulation in the brain has been associated to the pathogenesis of neurodegenerative disorders. We have previously demonstrated that iron overload in the neonatal period results in severe and persistent memory deficits in adult rats. Alterations in histone acetylation have been associated with memory deficits in models of neurological disorders. Here we examine histone acetylation in the brain and the effects of the histone deacetylase inhibitor (HDACi) sodium butyrate (NaB) on memory in the neonatal iron overload model in rats. Rats received vehicle or 30.0-mg/kg Fe⁺² orally at postnatal days 12-14. When animals reached adulthood, they were given training in either novel object recognition or inhibitory avoidance. Histone acetylation in the dorsal hippocampus and the effects of NaB were examined in separate sets of rats. Iron overload led to a reduction in H3 lysine 9 acetylation in the hippocampus, without affecting the acetylation of other H3 and H4 lysine residues. A single systemic injection of NaB (1.2 g/kg) immediately after training ameliorated iron-induced memory impairments. The results suggest that a reduction in H3K9 acetylation might play a role in iron-induced memory impairment and support the view that HDACis can rescue memory dysfunction in models of brain disorders.


Assuntos
Encéfalo/metabolismo , Butiratos/uso terapêutico , Inibidores de Histona Desacetilases/uso terapêutico , Histonas/metabolismo , Ferro/efeitos adversos , Lisina/metabolismo , Transtornos da Memória , Acetilação/efeitos dos fármacos , Análise de Variância , Animais , Animais Recém-Nascidos , Aprendizagem da Esquiva/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Modelos Animais de Doenças , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/patologia , Ratos , Ratos Wistar , Reconhecimento Psicológico/efeitos dos fármacos , Estatísticas não Paramétricas
9.
Theriogenology ; 65(5): 958-78, 2006 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-16242762

RESUMO

Ejaculated semen is washed for in vitro fertilization or diluted and processed to allow optimal and long-term low temperature liquid- and cryo-preservation. However, sperm are vulnerable to the washing, dilution, temperature and osmotic changes involved in sperm storage. In this review, a number of techniques are considered for detecting damaged spermatozoa. Staining protocols have been developed to detect the membrane and organelle integrity of mammalian sperm cells. Plasma membrane integrity is usually assessed after staining cells with membrane-impermeable dyes or alternatively with acetylated membrane (AM) permeable probes that are selectively de-esterified and become membrane impermeable and thus entrapped into viable cells only (AM ester loading). Organelle-specific dyes are commonly used to detect functionality of mitochondria or the acrosome. A distortion in the lateral and bilayer organization of lipids as well as the peroxidation of fatty acid moieties can be quantified and localized in living sperm. The relation of a disordering in the sperm membrane's lipid architecture and sperm deterioration versus capacitation is discussed. Finally, the integrity of sperm DNA can be measured at three different levels by assessing the degree of DNA-protamine condensation, the incidence of breaks and nicks in the DNA and the frequency of fragmentation of the nuclei into sub-haploid apoptotic bodies. The relevance of detecting DNA aberrations and especially the putative link to the incidence of apoptosis is critically considered.


Assuntos
Criopreservação/veterinária , Peroxidação de Lipídeos , Preservação do Sêmen/veterinária , Capacitação Espermática/fisiologia , Espermatozoides/fisiologia , Acrossomo/fisiologia , Animais , Masculino , Lipídeos de Membrana/análise , Preservação do Sêmen/efeitos adversos , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/ultraestrutura
10.
J Pediatr (Rio J) ; 77(5): 369-73, 2001.
Artigo em Português | MEDLINE | ID: mdl-14647840

RESUMO

OBJECTIVE: To assess the prevalence of prenatal exposure to cocaine in a sample of newborns using two methods: fluorescence polarization immunoassay and interview with the mother. METHODS: This cross-sectional study was carried out in a university teaching hospital. The population included all live births between March 23, 1999 and June 01, 1999 (n=847). Exposure was determined by a benzoylecgonine-positive meconium specimen and/or by a positive interview with the mother. RESULTS: The prevalence of prenatal exposure to cocaine in this sample was 2.4% (16 cases) according to the interviews, and 3.4% (25 cases) according to the meconium analysis. A rate of 4.6% (34 cases) was found when both methods were associated. CONCLUSIONS: We observed that the meconium test was more effective than the maternal interview for the diagnosis of prenatal exposure to cocaine. The meconium analysis enhanced diagnostic chances by 53.4%, compared to 26% in the case of maternal interview.

11.
Rev Port Cardiol ; 19(3): 291-7, 2000 Mar.
Artigo em Inglês, Português | MEDLINE | ID: mdl-10804775

RESUMO

AIM: To evaluate primary angioplasty results for the treatment of acute myocardial infarction complicated by cardiogenic shock on admission. POPULATION AND METHODS: Retrospective analysis of 11 consecutive patients with acute myocardial infarction complicated by cardiogenic shock (defined as systolic blood pressure below 80 mmHg and signs of hypoperfusion, despite volume expanders and/or vasopressors infusion) treated with primary angioplasty. Clinical characteristics, angiographic data, hospital outcome and follow-up were analysed. RESULTS: There were ten males (90.9%) with a mean age of 66 years. Eight patients had anterior wall myocardial infarction and three patients had inferior wall myocardial infarction, two of which with extension to the right ventricle. The mean time between symptom onset and angioplasty was 3.5 hours. Three patients had left main coronary artery occlusion; three patients had single vessel disease and five patients had multivessel disease. The angiographic success rate (open infarct-related artery and TIMI III flow) was 90.9% (ten patients). Stent implantation was performed in five patients. Abciximab was given in five patients. In-hospital mortality rate was 36.4% (four patients). The surviving patients had a mean ejection fraction of 43.1% on discharge. In a mean follow-up of 16.2 months, one patient had coronary artery bypass graft and one had stroke. CONCLUSION: Based on published data, our experience with this short series of cases shows that primary angiography should be regarded as a positive option for the treatment of acute myocardial infarction complicated by cardiogenic shock.


Assuntos
Angioplastia Coronária com Balão , Infarto do Miocárdio/terapia , Choque Cardiogênico/terapia , Idoso , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/mortalidade , Admissão do Paciente , Recidiva , Estudos Retrospectivos , Choque Cardiogênico/etiologia , Choque Cardiogênico/mortalidade , Fatores de Tempo , Resultado do Tratamento
12.
Rev Port Cardiol ; 19(2): 227-31, 2000 Feb.
Artigo em Português | MEDLINE | ID: mdl-10763352

RESUMO

OBJECTIVE: We analyse the value of the clinical data, isolated or associated with the stress EKG (SEKG) variables, in the detection of angiographic restenosis (AR: lesion > 50%), in a group of patients (pts) submitted to coronary angioplasty (PTCA) with stenting. POPULATION AND METHODS: 105 patients were followed prospectively (male: 87%; age: 56 +/- 10); clinical evaluation was performed in the 1st, 3rd and 6th month, SEKG in the 4th month and recatheterization for angiographic control in the 6th month. The vascular risk factors, cause of admission, medication at discharge, angiographic and procedure characteristics were analysed. RESULTS: The most frequent vascular risk factors were hypertension (42%), smoking (64%), and dyslipidemia (52%); 30% had previous ischemic heart disease. The indication for PTCA was myocardial infarction (direct PTCA or residual ischemia) in 42% and angina in 59%. All patients were discharged with AAS and ticlopidine, 38% with beta-blockers, 59% with calcium channel blockers and 92% with nitrates. Thirty-eight percent had multivessel disease. They were submitted to dilatation with the implantation of 128 stents in 199 vessels. An intraaortic balloon pump was used in 13% and Abciximab in 47% of the procedures. In the recatheterization for angiographic control in the sixth month, 30 patients had angiographic restenosis (AR rate = 25.2%). In the clinical evaluation, 22 patients (20.9%) had angina, and 14 of them had angiographic restenosis (clinical restenosis rate = 13.3%). In the 16 asymptomatic patients with AR, 5 had positive SEKG. CONCLUSION: The presence of angina in a group of patients submitted to coronary angioplasty with stenting has a low sensitivity (54%), a good specificity (88%), a positive predictive value of 64% and negative of 83% in the detection of angiographic restenosis. The association with clinical data improves sensitivity (83%), with a decrease in specificity (61%).


Assuntos
Angioplastia Coronária com Balão , Oclusão de Enxerto Vascular/diagnóstico , Stents , Idoso , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Sensibilidade e Especificidade
13.
Photochem Photobiol ; 67(2): 184-91, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9487797

RESUMO

The larger photobiological activity of visnagin (VI) versus khellin (KH) toward several living organisms, including fungi, viruses, yeasts and bacteria, induced a detailed investigation of the photophysical properties of these naturally occurring furanochromones, using laser-flash-photolysis, photoacoustic calorimetry and fluorescence (steady-state and time-resolved) techniques in solvents with different polarity and content of water, including micelles and vesicles. The results have shown that the magnitude of all the three rate constants out of S1 (radiative, kf; internal conversion, kic and intersystem crossing, kisc) for VI and KH strongly depend on the solvent, namely on its hydrogen bonding ability and polarity. The changes of kf and kisc are due to the solvent-assisted mixing and/or inversion of the two first singlet excited states (1n, pi and 1 pi, pi), while kic increases with a decrease of the S0-S1 energy gap. As a consequence, the quantum yield of triplet formation (phi T) strongly decreases from values of approximately 0.8 in dioxane to < 0.05 in water for both compounds. The magnitude of solvent polarity/hydrogen bonding ability required, at which the state order is inverted and phi T starts to decrease, is greater for VI than for KH and consequently phi T (VI) >> phi T (KH) over a broad range of water content including that appropriate to the environment of the compounds in a living system. These facts account for the larger photobiological activity of VI with respect to KH, regarding both the fungus Fusarium culmorum L. and the wild strain of Escherichia coli, studied by us.


Assuntos
Quelina/análogos & derivados , Quelina/química , Quelina/farmacologia , Fenômenos Químicos , Físico-Química , Escherichia coli/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Fotobiologia , Fotoquímica , Espectrometria de Fluorescência/métodos
14.
AMB Rev Assoc Med Bras ; 36(2): 110-2, 1990.
Artigo em Português | MEDLINE | ID: mdl-1965667

RESUMO

The authors present a rare case of closed abdominal trauma in a five year old girl resulting from a washtub fall on her causing three lacerations in the middle third of the esophagus, identified 48 hours after the trauma. The stitcher surgical treatment of the lacerations associated with gastrostomy and lengthy parenteral nutrition did not prevent the recurrence of the esophagus-pleural fistula, and an esophagectomy plus cervical esophagostomy was required. After a 10-month follow-up, the digestive passage was reconstructed by an esophagocoloplasty. At present, after 5 years of follow-up, the patient is cured. The authors discuss the causes of esophagus rupture in children and its etiopathogeny. They propose that preservativement the esophagus is the best initial treatment, in spite of the foot that this procedure was ineffective in the present case.


Assuntos
Esôfago/lesões , Ferimentos não Penetrantes/complicações , Pré-Escolar , Feminino , Humanos , Ruptura , Toracotomia , Ferimentos não Penetrantes/cirurgia
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