Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 642
Filtrar
1.
Sci Rep ; 14(1): 9156, 2024 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-38644369

RESUMO

Intervertebral Disc (IVD) degeneration has been associated with a chronic inflammatory response, but knowledge on the contribution of distinct IVD cells, namely CD44, to the progression of IVD degeneration remains elusive. Here, bovine nucleus pulposus (NP) CD44 cells were sorted and compared by gene expression and proteomics with the negative counterpart. NP cells were then stimulated with IL-1b (10 ng/ml) and dynamics of CD44 gene and protein expression was analyzed upon pro-inflammatory treatment. The results emphasize that CD44 has a multidimensional functional role in IVD metabolism, ECM synthesis and production of neuropermissive factors. CD44 widespread expression in NP was partially associated with CD14 and CD45, resulting in the identification of distinct cell subsets. In conclusion, this study points out CD44 and CD44-based cell subsets as relevant targets in the modulation of the IVD pro-inflammatory/degenerative cascade.


Assuntos
Receptores de Hialuronatos , Inflamação , Degeneração do Disco Intervertebral , Núcleo Pulposo , Animais , Bovinos , Núcleo Pulposo/metabolismo , Núcleo Pulposo/patologia , Receptores de Hialuronatos/metabolismo , Receptores de Hialuronatos/genética , Inflamação/metabolismo , Inflamação/patologia , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Células Cultivadas , Interleucina-1beta/metabolismo , Proteômica/métodos
2.
Braz J Biol ; 84: e276146, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422282

RESUMO

The objective of this work was characterizing persimmons of the 'Giombo' and 'Rama Forte' cultivars harvested at different ripening stages in the Brazilian semiarid. Fruits were harvested at three ripening stages - green, semi-ripe and ripe - then evaluated for the following characteristics: fruit weight and diameter, skin and pulp color, fruit firmness, pulp pH, soluble solids content, titratable acidity, SSC/TA ratio, total soluble sugars, reducing sugars, astringency index, and the contents of tannin, vitamin C, carotenoid, ß-carotene, and total extractable polyphenols. Also, total antioxidant activity by the DPPH and ABTS methods and pectin methylesterase, and polygalacturonase enzyme activities were evaluated. Two experiments were carried out in a completely randomized design, one for each cultivar, with treatments consisting of different stages of maturation, with five replications of three fruits each. Data were submitted to analysis of variance and the differences between the means were compared using the Tukey test at 5% probability. Fruit firmness and soluble solids content did not vary between maturation stages for any of the cultivars. However, the skin color index increased with advancing maturation for both 'Giombo' and 'Rama Forte'. The astringency index, the content of total extractable polyphenols, soluble tannins and the antioxidant capacity were lower in fruits harvested at the ripe stage, for both cultivars. It can be concluded that persimmons of the 'Giombo' and 'Rama Forte' cultivars present better physicochemical quality characteristics when harvested when ripe, with a totally yellow skin.


Assuntos
Antioxidantes , Diospyros , Antioxidantes/farmacologia , Brasil , Ácido Ascórbico , Açúcares
3.
Science ; 382(6671): 679-683, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37943897

RESUMO

Interactions between plants and herbivores are central in most ecosystems, but their strength is highly variable. The amount of variability within a system is thought to influence most aspects of plant-herbivore biology, from ecological stability to plant defense evolution. Our understanding of what influences variability, however, is limited by sparse data. We collected standardized surveys of herbivory for 503 plant species at 790 sites across 116° of latitude. With these data, we show that within-population variability in herbivory increases with latitude, decreases with plant size, and is phylogenetically structured. Differences in the magnitude of variability are thus central to how plant-herbivore biology varies across macroscale gradients. We argue that increased focus on interaction variability will advance understanding of patterns of life on Earth.


Assuntos
Variação Biológica da População , Herbivoria , Defesa das Plantas contra Herbivoria , Plantas , Ecossistema , Filogenia , Animais , Evolução Biológica
4.
J Phys Chem C Nanomater Interfaces ; 127(31): 15435-15442, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37706058

RESUMO

We present an abinitio study of the quasi-2D layered perovskite Sr3Hf2O7 compound, performed within the framework of the density functional theory and lattice dynamics analysis. At high temperatures, this compound takes a I4/mmm centrosymmetric structure (S.G. n. 139); as the temperature is lowered, the symmetry is broken into other intermediate polymorphs before reaching the ground-state structure, which is the Cmc21 ferroelectric phase (S.G. n. 36). One of these intermediate polymorphs is the Ccce structural phase (S.G. n. 68). Additionally, we have probed the C2/c system (S.G n. 15), which was obtained by following the atomic displacements corresponding to the eigenvectors of the imaginary frequency mode localized at the Γ-point of the Ccce phase. By observing the enthalpies at low pressures, we found that the Cmc21 phase is thermodynamically the most stable. Our results show that the I4/mmm and C2/c phases never stabilize in the 0-20 GPa range of pressure values. On the other hand, the Ccce phase becomes energetically more stable at around 17 GPa, surpassing the Cmc21 structure. By considering the effect of entropy and the constant-volume free energies, we observe that the Cmc21 polymorph is energetically the most stable phase at low temperature; however, at 350 K, the Ccce system becomes the most stable. By probing the volume-dependent free energies at 19 GPa, we see that Ccce is always the most stable phase between the two structures and also throughout the studied temperature range. When analyzing the phonon dispersion frequencies, we conclude that the Ccce system becomes dynamically stable only around 19-20 GPa and that the Cmc21 phase is metastable up to 30 GPa.

5.
Braz J Biol ; 83: e271339, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37729210

RESUMO

Uncaria tomentosa is a plant native to the Amazon that has immunomodulatory and antitumor properties due to the alkaloids found in the plant, being able to modify the immune response by potentiating or suspending the action of cytokines secreted by macrophages that induce the immune response, either by the classical route (M1) or through the alternative route (M2). Macrophages activated by M1 convert L-arginine into L-citrulline and nitric oxide (NO), whereas macrophages activated by the M2 pathway use the enzymatic activity of arginase to convert the same substrate into L-ornithine and urea. The aim of this work was to evaluate the immunostimulating activity of the crude hydroalcoholic extract from the bark of the U. tomentosa stem in RAW 264.7 macrophages. Concentrations of 0.2, 0.1 and 0.05 mg/mL of U. tomentosa extract associated with LPS, INF-γ and IL-4 inducers were tested by determining NO production and arginase enzyme activity. Nitric oxide production was enhanced by the extract when associated with LPS and LPS + INF-γ inducers. In the activity of the arginase enzyme, the extract decreased the stimulation of IL-4 on the enzyme, mainly at 0.2 mg/mL concentration. Therefore, it is concluded that the crude hydroalcoholic extract of the stem bark of U. tomentosa in RAW 264.7 cells, at a concentration of 0.2 mg/mL, showed considerable pro-inflammatory activity.


Assuntos
Unha-de-Gato , Arginase , Interleucina-4 , Lipopolissacarídeos/farmacologia , Óxido Nítrico , Macrófagos , Extratos Vegetais/farmacologia
6.
Braz J Biol ; 83: e268747, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37466509

RESUMO

Areas planted with Eucalyptus urophylla S.T. Blake variety platyphylla F. Muell. (Myrtaceae) expand annually in most regions of Brazil. Many lepidopteran species defoliate this plant, but with damage varying per species. The objective of this study was to identify the pest status of lepidopteran defoliators based in the faunistic analysis of these insects and of their natural enemies on E. urophylla variety platyphylla plantations in a representative producing region of Brazil. Adult moths of lepidopterans and of their natural enemies were captured using a light trap, installed every two weeks, from September 2016 to August 2018. A total of 183, 10, three and 139 lepidopteran species was captured and classified as primary, secondary, without defined importance to eucalypt plants and non-identified with 1,419, seven, 465 and 876 individuals, respectively. Two primary pest species were constants, two accessories and six accidentals and all secondary ones were accidentals. Six primary pest species were common and dominant and four non-dominants. Faunistic indices indicated the main lepidopteran species that should be monitored in pest management programs. Seven hymenopteran species (65 individuals), three dipterans (49 individuals) and two hemipterans (four individuals) were the natural enemies collected using light traps. The monitoring of lepidopteran pests with light traps can contribute to the management and to reduce damage and control costs for these species, besides identifying natural enemies for biological control programs in Eucalyptus plantations.


Assuntos
Eucalyptus , Lepidópteros , Myrtaceae , Animais , Insetos , Brasil
7.
Braz J Biol ; 83: e270966, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283336

RESUMO

Terpenoids, also named terpenes or isoprenoids, are a family of natural products found in all living organisms. Many plants produce terpenoids as secondary metabolites, and these make up a large part of essential oils. One of most important characteristic is that the compounds are volatile, have odor and can be used in a variety of applications in different industrial segments and traditional medicine. Brazil has a rich and diverse flora that can be used as a source of research for obtaining new molecules. Within the Brazilian flora, it is worth mentioning the Caatinga as an exclusively Brazilian biome where plants adapt to a specific series of weather conditions and therefore become a great storehouse of the terpenoid compounds to be described herein. Fungal infections have become increasingly common, and a great demand for new agents with low toxicity and side effects has thus emerged. Scientists must search for new molecules exhibiting antifungal activity to develop new drugs. This review aims to analyze scientific data from the principal published studies describing the use of terpenes and their biological applications as antifungals.


Assuntos
Óleos Voláteis , Terpenos , Terpenos/farmacologia , Terpenos/metabolismo , Antifúngicos/farmacologia , Brasil , Óleos Voláteis/farmacologia , Plantas
8.
Int J Numer Method Biomed Eng ; 39(7): e3715, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37151128

RESUMO

Cell proliferation is vital for the development and homeostasis of the human body. For such to occur, cells go through the cell cycle during which they replicate their genetic material and ultimately complete cellular division, when one cell divides into two new cells with equal genetic material. However, if there are some errors or abnormalities during the cell cycle that disrupt the balance between cell death and proliferation, severe problems can occur, such as tumour development, which is currently one of the leading causes of death in the world. Nowadays, mathematical and computational models are used to understand and study several biological mechanisms and processes, namely cellular proliferation. Over the last forty-five years, several models have attempted to describe cell proliferation and its regulation. Due to the complexity of the process, numerous assumptions and simplifications have been considered. This work presents a review of some of these models, focusing mainly on mammalian or generic eukaryotic models. Previously published continuum, discrete and hybrid approaches are presented and compared, in order to understand and highlight the relevance and capabilities of these models, their shortcomings and future challenges.


Assuntos
Modelos Biológicos , Neoplasias , Animais , Humanos , Ciclo Celular , Proliferação de Células , Mamíferos
9.
Eur Ann Allergy Clin Immunol ; 55(4): 152-160, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36927821

RESUMO

Summary: Hereditary α-tryptasemia (HαT) is a common autosomal dominant genetic trait with variable penetrance associated with increased serum baseline tryptase (SBT) levels. Clinical manifestations may range from an absence of symptoms to overtly severe and recurrent anaphylaxis. Symptoms have been claimed to result from excessive activation of EGF-like module-containing mucin-like hormone receptor-like 2 (EMR2) and protease-activated receptor 2 (PAR-2) receptors by α/ß-tryptase heterotetramers. Herein, we aimed to review the evidence on whether HαT can be considered a hereditary risk factor or a modifying factor for anaphylaxis.Increased SBT levels have been linked to an increased risk of anaphylaxis. Likewise, recent studies have shown that HαT might be associated with a higher risk of developing anaphylaxis and more severe anaphylaxis. The same has also been shown for patients with clonal mast cell disorders, in whom the co-existence of HαT might lead to a greater propensity for severe, potentially life-threatening anaphylaxis. However, studies leading to such conclusions are generally limited in sample size, while other studies have shown opposing results. As such, further studies investigating the potential association of HαT with anaphylaxis caused by different triggers, and different severity grades, in both patients with clonal mast cell activation syndromes and the general population are still needed.


Assuntos
Anafilaxia , Síndrome da Ativação de Mastócitos , Mastocitose , Humanos , Anafilaxia/diagnóstico , Anafilaxia/genética , Mastócitos , Mastocitose/diagnóstico , Fatores de Risco , Triptases/genética
10.
Braz J Med Biol Res ; 56: e12454, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36856253

RESUMO

The use of routine magnetic resonance imaging (MRI) to potentially assess skeletal fragility has been widely studied in osteoporosis. The aim of this study was to evaluate bone texture attributes (TA) from routine lumbar spine (LS) MRI and their correlation with vertebral fragility fractures (VFF) and bone mineral density (BMD). Sixty-four post-menopausal women were submitted to LS densitometry, total spine radiographs, and routine T2-weighted LS MRI. Twenty-two TA were extracted with the platform IBEX from L3 vertebra. The statistical difference was evaluated using ANOVA and Duncan's post-test. Correlation analyses were performed using Spearman's coefficient. Statistical significance was considered when P<0.05. The results did not show a significant difference in BMD between the women with and without fractures. Two bone TA (cluster tendency and variance) were significantly lower in the fracture group. Cluster tendency with VFF in osteopenia was 1.54±1.37 and in osteoporosis was 1.11±58. Cluster tendency without VFF in osteopenia was 2.23±1.38 and in osteoporosis was 1.88±1.14). Variance with VFF in osteopenia was 1.44±1.37 and in osteoporosis was 1.13±59. Variance without VFF in osteopenia was 2.34±1.38 and in osteoporosis was 1.89±1.14. There was a significant correlation between BMD and cluster prominence (r=0.409), cluster tendency (r=0.345), correlation (r=0.570), entropy (r=0.364), information measure corr1 (r=0.378), inverse variance (r=0.449), sum entropy (r=0.320), variance (r=0.338), sum average (r=-0.274), and sum variance (r=-0.266). Our results demonstrated the potential use of TA extracted from routine MRI as a biomarker to assess osteoporosis and identify the tendency of skeletal fragility vertebral fractures.


Assuntos
Doenças Ósseas Metabólicas , Osteoporose , Humanos , Feminino , Densidade Óssea , Vértebras Lombares/diagnóstico por imagem , Osteoporose/diagnóstico por imagem , Imageamento por Ressonância Magnética
11.
Clin Radiol ; 78(3): e268-e278, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36623977

RESUMO

AIM: To evaluate bone marrow fat fraction using the Dixon technique (FFDix) of magnetic resonance imaging (MRI) as a potential biomarker of haemolysis and clinical severity in the overall assessment and follow-up of sickle cell disease (SCD) patients. MATERIAL AND METHODS: The present study was a cross-sectional study in which healthy individuals and SCD patients (matched for age, sex, and weight) were subjected to MRI of the lumbar spine and pelvis to quantify FFDix in the bone marrow using the Dixon technique. SCD severity was analysed by clinical and laboratory data, and an online calculator. A high degree of haemolysis was defined using the cut-off values haemoglobin (Hb) ≤10 g/dl, lactate dehydrogenase (LDH) ≥325 U/l, reticulocytes ≥3% and total bilirubin (TB) ≥1.2 mg/dl. Pearson's correlation, receiver operating characteristic (ROC) curve and binary logistic regression analysis were performed. RESULTS: Forty-eight SCD patients (26 homozygous: HbSS and 22 compound heterozygous: HbSC) and 48 healthy individuals participated in the study. FFDix was lower in SCD patients than in the control group, showing even lower values in the HbSS subtype and patients with a higher degree of haemolysis. HbSC patients with a higher degree of haemolysis using hydroxyurea (medium dosage 9.8 mg/kg/day) had lower FFDix. ROC curves and odds ratios for detecting patients with a higher degree of haemolysis at the different FFDix measurement sites demonstrated excellent performance: iliac bones (cut-off ≤16.75%, AUC = 0.824, p<0.001), femoral heads (cut-off ≤46.7%, AUC = 0.775, p=0.001), lumbar vertebrae (cut-off ≤7.8%, AUC = 0.755, p=0.002). CONCLUSION: Decreased FFDix is indicative of higher degree of haemolysis and SCD severity with great potential as a non-invasive biomarker contributing to the overall assessment and follow-up of SCD patients.


Assuntos
Anemia Falciforme , Doença da Hemoglobina SC , Humanos , Hemólise , Medula Óssea , Estudos Transversais , Anemia Falciforme/complicações , Anemia Falciforme/diagnóstico por imagem , Hemoglobina Falciforme , Biomarcadores
12.
Eur Ann Allergy Clin Immunol ; 55(1): 9-18, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-33949172

RESUMO

Summary: Background. Chronic urticaria (CU) is a frequent disease, with a prevalence of at least 1%. It is characterized by pruritic wheals, angioedema or both for a period longer than 6 weeks. Objective. Identify the demographic, clinical, laboratory and therapeutic profile of patients treated in a Portuguese Urticaria Center of Reference and Excellence (UCARE) and compare it with international series. Methods. Retrospective analysis of database of patients observed in a specialized urticaria outpatient clinic, from January 2017 through September 2019, of a UCARE center in Portugal. Demographic and clinical features, laboratory findings and pharmacological treatment were obtained from the records. Descriptive analyses were performed for all variables. Chi square and fisher's exact tests were applied to analyze the independence of variables and the fit of distribution. P less than 0.05 was considered significant. Results. During this period, 477 patients were observed, of whom 429 (90%) were diagnosed with chronic urticaria. Mean age (years) at the onset of symptoms was 43.7 (standard deviation (SD) 17.6, range 6-88) and at diagnosis 46.7 (SD 17.8, range 6-88) resulting in an average diagnostic delay of 3 years (range 0-25). Median follow-up period since first attendance in the specialized outpatient clinic was 1.7 years (interquartile range (IQR) 0.79, range 0.1-2.75) . Concerning the whole group of CU patients, 347 (81%) had chronic spontaneous urticaria (CSU) - 79% female, 39 (9%) had isolated chronic inducible urticaria (CIndU) and 43 (10%) had CSU with CIndU. Autologous serum skin test (ASST) was done in 76 patients (positive in 24 (32%)) and basophil activation test (BAT) was done in 38 (positive in 13 (34%)). At the moment of study, 204 (48%) of CU patients were medicated with a second-generation H1-antihistamine (sgAH) daily (first-line therapy), 99 (23%) with sgAH up to four times the standard dose (second-line therapy) and 126 (29%) with omalizumab (third-line therapy). Additionally, 7 (2%) patients were completing a short course of systemic corticosteroids for management of disease exacerbation. Disease control was achieved in 316 of CSU patients (81%). Conclusions. Referral to a specialized urticaria outpatient clinic is important for a proper assessment of the disease and adequately symptom control.


Assuntos
Urticária Crônica , Antagonistas não Sedativos dos Receptores H1 da Histamina , Urticária , Humanos , Feminino , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Masculino , Portugal/epidemiologia , Estudos Retrospectivos , Diagnóstico Tardio , Urticária/diagnóstico , Urticária/tratamento farmacológico , Urticária/epidemiologia , Urticária Crônica/tratamento farmacológico , Omalizumab/uso terapêutico , Antagonistas não Sedativos dos Receptores H1 da Histamina/uso terapêutico , Urticária Crônica Induzida , Doença Crônica
13.
Eur Ann Allergy Clin Immunol ; 55(1): 29-34, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-33949175

RESUMO

Summary: Background. The adrenaline autoinjector (AAi) is universally recommended as the first-line treatment for anaphylactic reactions occurring outside the medical setting. The quantification of its acquisition may help estimate the prevalence of patients at risk of anaphylaxis with an indication for AAi. Objective. Evaluation of the global and regional frequency of AAi purchases in Mainland Portugal between 2003-2017 and calculate the inherent costs in 2017. Methods. AAi acquisition distribution analysis along this period. The population was divided in two age groups according to the adrenaline dosage. Results. A total of 10,993 AAi units of 0.15mg/0.3mL and 28,619 of 0.3mg/0.3mL were acquired in these 15 years, with an annual average of 733 and 1908 units, respectively. In cumulative values terms, Lisbon showed the highest number of AAI acquired and higher prevalence per region/100,000 inhabitants in both groups. In 2017, the annual cost for each age group was 64,202.71 € 187,447.70 € for patients and € 37,706.35 / 110,113.30 € for the National Health System. Conclusions. In the last 15 years, there was a progressive increase in AAi acquisition. We estimate a rate of anaphylaxis occurrence in Portugal according to AAi aquisition of 0.165%.


Assuntos
Anafilaxia , Epinefrina , Humanos , Epinefrina/uso terapêutico , Anafilaxia/tratamento farmacológico , Anafilaxia/epidemiologia , Portugal/epidemiologia , Autoadministração , Prevalência
14.
Acta Biomater ; 155: 667-683, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36328124

RESUMO

The host inflammatory response to biomaterials conditions their capacity to promote tissue repair, and macrophage polarization shift from M1 to M2 is determinant in this process. Previous work showed that extracts of a combination between fibrinogen and metallic magnesium materials acted synergistically to reduce macrophage inflammatory phenotype. The hypothesis underlying the current work was that the ability of magnesium-modified fibrinogen scaffolds to modulate macrophage phenotype depends on the concentration of magnesium. Thus, Fibrinogen (Fg) scaffolds incorporating precise concentrations of magnesium sulfate (Mg: 0, 10, 25, 50 mM) were developed and characterized. Mg incorporation in Fg scaffolds increased surface charge, while porosity decreased with increasing Mg concentrations, but only Fg scaffolds with 10 mM of Mg (FgMg10) had significantly improved mechanical properties. Human macrophages cultured on FgMg10 scaffolds, showed increased M2 and decreased M1 polarization, when compared to those cultured on scaffolds with 0, 25 and 50 mM of Mg. Macrophage polarization results were independent of the anion used (chloride or sulfate). Macrophage modulation by FgMg10 scaffolds involved reduced NF-κB p65 nuclear translocation, and impacted production of pro-inflammatory mediators (e.g. IFNγ, IL-12, TNF-⍺, IP-10). Importantly, FgMg10 scaffolds implanted in vivo increased the expression of M2 marker CD163, in macrophages from inflammatory exudates, compared to Sham and Fg-implanted animals, increasing the M2:M1 ratio. A cytokine/chemokine array showed that, while both Fg and FgMg10 scaffolds decreased inflammatory mediators, only FgMg10 decreased IL-1ß, IP-10, MIP-2, MDC and MIP-3⍺, compared to Sham-operated animals. This study demonstrated that incorporation of 10mM of Mg modulated inflammation, promoting M2 macrophage polarization in vitro and in vivo. STATEMENT OF SIGNIFICANCE: Developing biomaterials that can modulate inflammation and promote macrophage phenotype switch from M1 to M2 is crucial to promote a regenerative microenvironment. Our previous work showed that extracts of a combination between fibrinogen (Fg) and metallic magnesium (Mg) materials synergistically reduced macrophage pro-inflammatory phenotype. Herein, we tested the hypothesis that macrophage modulation was dependent on Mg concentration. A new family of Fg porous scaffolds incorporating different amounts of Mg (0, 10, 25 and 50 mM) was produced and characterized. We observed that only the combination of Fg scaffolds with 10 mM of Mg (FgMg10) significantly changed the scaffolds mechanical properties and directed macrophages towards a M2 phenotype, reducing the production of inflammatory mediators, both in vitro and in vivo.


Assuntos
Fibrinogênio , Magnésio , Animais , Humanos , Materiais Biocompatíveis/metabolismo , Quimiocina CXCL10/metabolismo , Fibrinogênio/metabolismo , Inflamação/metabolismo , Macrófagos/metabolismo , Magnésio/farmacologia , Magnésio/metabolismo , Fenótipo
16.
Braz. j. biol ; 83: 1-6, 2023. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468955

RESUMO

The possible interference of resistant pest’s populations to insecticides in natural enemies in the action thas not been clarified yet. Thus, this study aimed to evaluate Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) performance on Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) eggs with resistance frequency to the Metaflumizone over six generations of product exposure. Egg cards (2.0 x 7.0 cm) containing eggs from two populations of S. frugiperda, (resistant to Metaflumizone and the other susceptible), were exposed to T. pretiosum females for 24 hours in free-choice and no-choice testing in three generations (G1, G4, and G6). A completely randomized experimental design was used with 25 replications, each consisting of an egg card (experimental unit) containing 20 eggs. The parameters evaluated were: parasitism (%), emergence (%), sex ratio, number of emerged parasitoids per egg and males/females longevity. ANOVA and Tukey test (P≤ 0.05) were applied on the results. Results showed a reduction in parasitism [41.0% (G1) and 28.4% (G4)], egg emergence (17.5%) and parasitoids/egg [16.2 (G4) and 17.2 (G6)] in eggs originating from the population with resistance frequency. Females emerging from G6 populations eggs without exposure to Metaflumizone had greater longevity (3.5 days more) than the resistant population. The sex ratio and male longevity were not affected. The results indicate a reduction in T. pretiosum activity if S. frugiperda populations have some frequency of resistance to Metaflumizone.


A possível interferência de populações de pragas resistentes na ação de inimigos naturais ainda não foi esclarecida. Assim, este trabalho teve como objetivo avaliar o desempenho de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) em ovos de Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) com frequência de resistência à Metaflumizona ao longo de seis gerações de exposição ao produto. Cartelas (2,0 x 7,0 cm) com ovos de duas populações de S. frugiperda, (resistente à Metaflumizona e outra suscetível), foram expostas às fêmeas de T. pretiosum por 24 horas em condições de livre escolha e sem chance de escolha por três gerações (G1, G4 e G6). O delineamento experimental foi inteiramente casualizado com 25 repetições, sendo cada repetição composta por uma cartela (unidade experimental) contendo 20 ovos. Os parâmetros avaliados foram: parasitismo (%), emergência (%), razão sexual, número de parasitoides emergidos por ovo e longevidade de machos e fêmeas. ANOVA e teste de Tukey (P≤ 0,05) foram aplicados aos dados coletados. Os resultados mostraram redução do parasitismo [41,0% (G1) e 28,4% (G4)], emergência de ovos (17,5%) e parasitoides/ovo [16,2 (G4) e 17,2 (G6)] em ovos oriundos da população com frequência de resistência. As fêmeas emergidas de ovos da população G6 sem exposição à Metaflumizona, tiveram maior longevidade (3,5 dias a mais) do que a população exposta ao inseticida. A razão sexual e a longevidade de machos não foram afetadas. Os resultados indicam uma redução na atividade de T. pretiosum se as populações de S. frugiperda apresentarem alguma frequência de resistência à Metaflumizona.


Assuntos
Animais , Himenópteros/efeitos dos fármacos , Inseticidas/administração & dosagem , Spodoptera/parasitologia
17.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469171

RESUMO

Abstract The possible interference of resistant pests populations to insecticides in natural enemies in the action thas not been clarified yet. Thus, this study aimed to evaluate Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) performance on Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) eggs with resistance frequency to the Metaflumizone over six generations of product exposure. Egg cards (2.0 x 7.0 cm) containing eggs from two populations of S. frugiperda, (resistant to Metaflumizone and the other susceptible), were exposed to T. pretiosum females for 24 hours in free-choice and no-choice testing in three generations (G1, G4, and G6). A completely randomized experimental design was used with 25 replications, each consisting of an egg card (experimental unit) containing 20 eggs. The parameters evaluated were: parasitism (%), emergence (%), sex ratio, number of emerged parasitoids per egg and males/females longevity. ANOVA and Tukey test (P 0.05) were applied on the results. Results showed a reduction in parasitism [41.0% (G1) and 28.4% (G4)], egg emergence (17.5%) and parasitoids/egg [16.2 (G4) and 17.2 (G6)] in eggs originating from the population with resistance frequency. Females emerging from G6 populations eggs without exposure to Metaflumizone had greater longevity (3.5 days more) than the resistant population. The sex ratio and male longevity were not affected. The results indicate a reduction in T. pretiosum activity if S. frugiperda populations have some frequency of resistance to Metaflumizone.


Resumo A possível interferência de populações de pragas resistentes na ação de inimigos naturais ainda não foi esclarecida. Assim, este trabalho teve como objetivo avaliar o desempenho de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) em ovos de Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) com frequência de resistência à Metaflumizona ao longo de seis gerações de exposição ao produto. Cartelas (2,0 x 7,0 cm) com ovos de duas populações de S. frugiperda, (resistente à Metaflumizona e outra suscetível), foram expostas às fêmeas de T. pretiosum por 24 horas em condições de livre escolha e sem chance de escolha por três gerações (G1, G4 e G6). O delineamento experimental foi inteiramente casualizado com 25 repetições, sendo cada repetição composta por uma cartela (unidade experimental) contendo 20 ovos. Os parâmetros avaliados foram: parasitismo (%), emergência (%), razão sexual, número de parasitoides emergidos por ovo e longevidade de machos e fêmeas. ANOVA e teste de Tukey (P 0,05) foram aplicados aos dados coletados. Os resultados mostraram redução do parasitismo [41,0% (G1) e 28,4% (G4)], emergência de ovos (17,5%) e parasitoides/ovo [16,2 (G4) e 17,2 (G6)] em ovos oriundos da população com frequência de resistência. As fêmeas emergidas de ovos da população G6 sem exposição à Metaflumizona, tiveram maior longevidade (3,5 dias a mais) do que a população exposta ao inseticida. A razão sexual e a longevidade de machos não foram afetadas. Os resultados indicam uma redução na atividade de T. pretiosum se as populações de S. frugiperda apresentarem alguma frequência de resistência à Metaflumizona.

18.
Braz. j. biol ; 83: e245273, 2023. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339412

RESUMO

Abstract The possible interference of resistant pest's populations to insecticides in natural enemies in the action thas not been clarified yet. Thus, this study aimed to evaluate Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) performance on Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) eggs with resistance frequency to the Metaflumizone over six generations of product exposure. Egg cards (2.0 x 7.0 cm) containing eggs from two populations of S. frugiperda, (resistant to Metaflumizone and the other susceptible), were exposed to T. pretiosum females for 24 hours in free-choice and no-choice testing in three generations (G1, G4, and G6). A completely randomized experimental design was used with 25 replications, each consisting of an egg card (experimental unit) containing 20 eggs. The parameters evaluated were: parasitism (%), emergence (%), sex ratio, number of emerged parasitoids per egg and males/females longevity. ANOVA and Tukey test (P≤ 0.05) were applied on the results. Results showed a reduction in parasitism [41.0% (G1) and 28.4% (G4)], egg emergence (17.5%) and parasitoids/egg [16.2 (G4) and 17.2 (G6)] in eggs originating from the population with resistance frequency. Females emerging from G6 populations eggs without exposure to Metaflumizone had greater longevity (3.5 days more) than the resistant population. The sex ratio and male longevity were not affected. The results indicate a reduction in T. pretiosum activity if S. frugiperda populations have some frequency of resistance to Metaflumizone.


Resumo A possível interferência de populações de pragas resistentes na ação de inimigos naturais ainda não foi esclarecida. Assim, este trabalho teve como objetivo avaliar o desempenho de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) em ovos de Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) com frequência de resistência à Metaflumizona ao longo de seis gerações de exposição ao produto. Cartelas (2,0 x 7,0 cm) com ovos de duas populações de S. frugiperda, (resistente à Metaflumizona e outra suscetível), foram expostas às fêmeas de T. pretiosum por 24 horas em condições de livre escolha e sem chance de escolha por três gerações (G1, G4 e G6). O delineamento experimental foi inteiramente casualizado com 25 repetições, sendo cada repetição composta por uma cartela (unidade experimental) contendo 20 ovos. Os parâmetros avaliados foram: parasitismo (%), emergência (%), razão sexual, número de parasitoides emergidos por ovo e longevidade de machos e fêmeas. ANOVA e teste de Tukey (P≤ 0,05) foram aplicados aos dados coletados. Os resultados mostraram redução do parasitismo [41,0% (G1) e 28,4% (G4)], emergência de ovos (17,5%) e parasitoides/ovo [16,2 (G4) e 17,2 (G6)] em ovos oriundos da população com frequência de resistência. As fêmeas emergidas de ovos da população G6 sem exposição à Metaflumizona, tiveram maior longevidade (3,5 dias a mais) do que a população exposta ao inseticida. A razão sexual e a longevidade de machos não foram afetadas. Os resultados indicam uma redução na atividade de T. pretiosum se as populações de S. frugiperda apresentarem alguma frequência de resistência à Metaflumizona.


Assuntos
Animais , Masculino , Feminino , Vespas , Himenópteros , Mariposas , Semicarbazonas , Razão de Masculinidade , Spodoptera
19.
Braz. j. med. biol. res ; 56: e12454, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1420760

RESUMO

The use of routine magnetic resonance imaging (MRI) to potentially assess skeletal fragility has been widely studied in osteoporosis. The aim of this study was to evaluate bone texture attributes (TA) from routine lumbar spine (LS) MRI and their correlation with vertebral fragility fractures (VFF) and bone mineral density (BMD). Sixty-four post-menopausal women were submitted to LS densitometry, total spine radiographs, and routine T2-weighted LS MRI. Twenty-two TA were extracted with the platform IBEX from L3 vertebra. The statistical difference was evaluated using ANOVA and Duncan's post-test. Correlation analyses were performed using Spearman's coefficient. Statistical significance was considered when P<0.05. The results did not show a significant difference in BMD between the women with and without fractures. Two bone TA (cluster tendency and variance) were significantly lower in the fracture group. Cluster tendency with VFF in osteopenia was 1.54±1.37 and in osteoporosis was 1.11±58. Cluster tendency without VFF in osteopenia was 2.23±1.38 and in osteoporosis was 1.88±1.14). Variance with VFF in osteopenia was 1.44±1.37 and in osteoporosis was 1.13±59. Variance without VFF in osteopenia was 2.34±1.38 and in osteoporosis was 1.89±1.14. There was a significant correlation between BMD and cluster prominence (r=0.409), cluster tendency (r=0.345), correlation (r=0.570), entropy (r=0.364), information measure corr1 (r=0.378), inverse variance (r=0.449), sum entropy (r=0.320), variance (r=0.338), sum average (r=-0.274), and sum variance (r=-0.266). Our results demonstrated the potential use of TA extracted from routine MRI as a biomarker to assess osteoporosis and identify the tendency of skeletal fragility vertebral fractures.

20.
Braz J Med Biol Res ; 55: e12015, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36383800

RESUMO

The aim of this study was to verify the relationship between quantitative T2 relaxation measurements of lumbar intervertebral discs (IVDs) and spinopelvic parameters in patients with chronic low back pain. The study was approved by the Clinical Hospital of the Ribeirao Preto Medical School (USP) Ethics Committee, and written consent was obtained from all patients. A total of 455 IVDs from 91 consecutive patients with chronic low back pain were included in this prospective study. All subjects were assessed using the Oswestry Disability Index and visual analogue scale questionnaires and were confirmed to have no other spine diseases except disc degeneration. Spinopelvic parameters including the pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), sagittal vertical axis (SVA), global tilt (GT), T1 pelvic angle (TPA), lumbar lordosis (LL), thoracic kyphosis (TK), pelvic incidence minus lumbar lordosis mismatch (PI-LL), and lack of lumbar lordosis (LLL) were measured. The study group was categorized according to the Roussouly classification. Sagittal T2 maps were acquired to extract the IVD relaxation times, and the complete manual segmentation of IVDs at all levels was performed using Display® software. Lumbar IVD T2 relaxation times showed significant correlation with PT (P<0.01), GT (P<0.01), TPA (P<0.01), PI-LL (P=0.01), and LLL (P=0.01). No difference was noted between Roussouly subtypes regarding T2 relaxation times at any disc level. Data from questionnaires showed no correlation with T2 relaxation times. Global tilt and T1 pelvic angle were correlated with IVD composition changes (T2 relaxometry). There was no correlation between clinical symptoms and IVD T2 relaxation times.


Assuntos
Disco Intervertebral , Lordose , Dor Lombar , Humanos , Lordose/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Dor Lombar/diagnóstico por imagem , Estudos Prospectivos , Estudos Retrospectivos , Disco Intervertebral/diagnóstico por imagem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...