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1.
Biochimie ; 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39029576

ABSTRACT

Bacterial resistance has become a serious public health problem in recent years, thus encouraging the search for new antimicrobial agents. Here, we report an antimicrobial peptide (AMP), called PEPAD, which was designed based on an encrypted peptide from a Kunitz-type plant peptidase inhibitor. PEPAD was capable of rapidly inhibiting and eliminating numerous bacterial species at micromolar concentrations (from 4µM to 10 µM), with direct membrane activity. It was also observed that the peptide can act synergistically with ciprofloxacin and showed no toxicity in the G. mellonella in vivo assay. Circular dichroism assays revealed that the peptide's secondary structure adopts different scaffolds depending on the environment in which it is inserted. In lipids mimicking bacterial cell membranes, PEPAD adopts a more stable α-helical structure, which is consistent with its membrane-associated mechanism of action. When in contact with lipids mimicking mammalian cells, PEPAD adopts a disordered structure, losing its function and suggesting cellular selectivity. Therefore, these findings make PEPAD a promising candidate for future antimicrobial therapies with low toxicity to the host.

2.
J Environ Sci Health B ; 59(6): 350-360, 2024.
Article in English | MEDLINE | ID: mdl-38736380

ABSTRACT

The aim of this study was to assess the efficacy of herbicides in association to control Rottboellia exaltata and Ipomoea quamoclit during pre-emergence while also to evaluate the potential impact on the sugarcane. The experimental design employed a randomized block with seven treatments and four replications. The treatments were: 1 - no herbicide application; 2 - indaziflam + sulfentrazone; 3 - indaziflam + diclosulam; 4 - indaziflam + tebuthiuron; 5 - flumioxazin + diclosulam, 6 - flumioxazin + pyroxasulfone and 7 - clomazone + sulfentrazone. The evaluated parameters were: percentage of weeds control, green coverage percentage (Canopeo® system), weed biomass (g m-2), itchgrass height, and sugarcane tiller. Several herbicide associations have been proven effective alternatives for managing itchgrass and cypressvine morningglory. The most successful treatments for itchgrass control were indaziflam + tebuthiuron (100%) and indaziflam + diclosulam (97%), whereas for cypressvine morningglory, the betters were indaziflam + sulfentrazone (97%), indaziflam + diclosulam (98%), indaziflam + tebuthiuron (97%), flumioxazin + diclosulam (94%), and clomazone + sulfentrazone (96%). All treatments reduced the weed biomass, with indaziflam + tebuthiuron being the safest option for protecting sugarcane.


Subject(s)
Herbicides , Saccharum , Weed Control , Herbicides/pharmacology , Weed Control/methods , Plant Weeds/drug effects , Ipomoea/drug effects
3.
Pest Manag Sci ; 80(9): 4594-4603, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38788160

ABSTRACT

BACKGROUND: Compatibility studies of insecticides and natural enemies usually focus on short-term lethal effects, without considering the long-term sublethal effects (including progeny). Even less-explored are the effects of commercial insecticides formulated with more than one active product. Short- and long-term lethal and sublethal effects were studied for the first time on the progeny of commercial formulations of spirotetramat, imidacloprid and a commercial mixture of these active ingredients on pupae of Diaeretiella rapae (M'ntosh) (Hymenoptera: Braconidae), an endoparasitoid of aphids considered to be a potential biological control agent. Insecticides were exposed topically on aphid mummies in which the parasitoid was in the pupal stage. RESULTS: Imidacloprid reduced adult emergence by more than 30% and prolonged intra-host development time with respect to control from half the maximum recommended field dose (MFRD). Spirotetramat and commercial mixture only showed significant effects on these endpoints at doses above the MFRD. The tested formulations did not affect adult longevity, sex ratio, and percentage of parasitism in the exposed generation. At low concentrations the active ingredients in the commercial mixture behave synergistically, whereas at medium and high concentrations they behave antagonistically. Considering the 10% lethal dose (LD10), imidacloprid showed the highest hazard coefficient, whereas the commercial mixture was more hazardous when considering the LD50 and LD90. The commercial mixture and imidacloprid induced higher adult emergence and altered the sex ratio in the progeny. CONCLUSIONS: The following order of toxicity on D. rapae can be established: imidacloprid > commercial mixture > spirotetramat. Joint use of this species with imidacloprid and commercial mixture should be avoided in integrated pest management programs. © 2024 Society of Chemical Industry.


Subject(s)
Aza Compounds , Insecticides , Neonicotinoids , Nitro Compounds , Pupa , Spiro Compounds , Wasps , Animals , Spiro Compounds/toxicity , Pupa/drug effects , Pupa/growth & development , Wasps/drug effects , Wasps/physiology , Wasps/growth & development , Aphids/drug effects , Aphids/parasitology , Female , Imidazoles/toxicity
4.
Eur J Pharmacol ; 975: 176636, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38729417

ABSTRACT

Endothelial cells express multiple receptors mediating estrogen responses; including the G protein-coupled estrogen receptor (GPER). Past studies on nitric oxide (NO) production elicited by estrogens raised the question whether 17-ß-estradiol (E2) and natural phytoestrogens activate equivalent mechanisms. We hypothesized that E2 and phytoestrogens elicit NO production via coupling to distinct intracellular pathways signalling. To this aim, perfusion of E2 and phytoestrogens to the precontracted rat mesentery bed examined vasorelaxation, while fluorescence microscopy on primary endothelial cells cultures quantified single cell NO production determined following 4-amino-5-methylamino-2',7'-difluoroescein diacetate (DAF) incubation. Daidzein (DAI) and genistein (GEN) induced rapid vasodilatation associated to NO production. Multiple estrogen receptor activity was inferred based on the reduction of DAF-NO signals; G-36 (GPER antagonist) reduced 75 % of all estrogen responses, while fulvestrant (selective nuclear receptor antagonist) reduced significantly more the phytoestrogens responses than E2. The joint application of both antagonists abolished the E2 response but not the phytoestrogen-induced DAF-NO signals. Wortmannin or LY-294002 (PI3K inhibitors), reduced by 90% the E2-evoked signal while altering significantly less the DAI-induced response. In contrast, H-89 (PKA inhibitor), elicited a 23% reduction of the E2-induced signal while blocking 80% of the DAI-induced response. Desmethylxestospongin-B (IP3 receptor antagonist), decreased to equal extent the E2 or the DAI-induced signal. Epidermal growth factor (EGF) induced NO production, cell treatment with AG-1478, an EGF receptor kinase inhibitor reduced 90% DAI-induced response while only 53% the E2-induced signals; highlighting GPER induced EGF receptor trans-modulation. Receptor functional selectivity may explain distinct signalling pathways mediated by E2 and phytoestrogens.


Subject(s)
Cyclic AMP-Dependent Protein Kinases , ErbB Receptors , Estradiol , Nitric Oxide , Phosphatidylinositol 3-Kinases , Phytoestrogens , Signal Transduction , Vasodilation , Animals , Phytoestrogens/pharmacology , Estradiol/pharmacology , Nitric Oxide/metabolism , Rats , Signal Transduction/drug effects , Vasodilation/drug effects , Cyclic AMP-Dependent Protein Kinases/metabolism , Phosphatidylinositol 3-Kinases/metabolism , ErbB Receptors/metabolism , Male , Isoflavones/pharmacology , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Genistein/pharmacology , Receptors, Estrogen/metabolism , Rats, Wistar
5.
Neotrop Entomol ; 53(3): 682-693, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38656592

ABSTRACT

Insecticides efficient against the target species while conserving natural enemies in the agroecosystem are required for IPM. With the imminent discontinuation of fipronil, a broad-spectrum insecticide, ethiprole, which belongs to the same group as phenylpyrazole (2B), and isocycloseram, a novel isoxazoline insecticide with distinct mode of action (30), provide options for controlling boll weevil. The susceptibility of the boll weevil, Anthonomus grandis grandis (Boh.), and two natural enemies [Eriopis connexa (Germar) and Bracon vulgaris Ashmead] to these insecticides were studied. Furthermore, the survival and biological traits of the lady beetle, E. connexa, exposed to fipronil, isocycloseram, and ethiprole were assessed. The LC50s values for fipronil, ethiprole, and isocycloseram for A. grandis grandis were 2.71, 0.32, and 0.025 mg a.i./L, respectively; 0.86, > 200, and 3.21 mg a.i./L for E. connexa; and 2.31, 592.94, and 0.18 mg a.i./L for B. vulgaris, respectively. The recommended rates of ethiprole did not cause mortality in adult lady beetles, although fipronil and isocycloseram were highly toxic. Lady beetle larvae and adults survived more than 80% when exposed to dried residues of ethiprole, but less than 10% when exposed to fipronil and isocycloseram. Lady beetle larvae development, reproduction, and predation rates of adults were similar between ethiprole and the control group. Although fipronil and ethiprole belong to the same insecticide group, the difference in toxicity to boll weevils and natural enemies is presented and discussed. Ethiprole was more toxic to boll weevils than to its parasitoid and lady beetle, and isocycloseram was highly toxic to all three species.


Subject(s)
Insecticides , Weevils , Animals , Weevils/drug effects , Isoxazoles/toxicity , Pyrazoles/toxicity , Coleoptera/drug effects
6.
J Pediatr ; 269: 114004, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38447756

ABSTRACT

OBJECTIVE: To examine clinical correlates and prevalence of food selectivity (FS) - ie, self-restricted diet, reluctance to try new foods - in children with autism spectrum disorder (ASD) ascertained from a general outpatient autism clinic. STUDY DESIGN: A multidisciplinary team (pediatric nurse practitioner, psychologist and dietitian) assessed medical and psychosocial histories and dietary habits in 103 children with ASD (mean age = 5.8 ± 2.2 years; range 2-10). Parents rated child mealtime behavior on the Brief Autism Mealtime Behavior Inventory (BAMBI) and disruptive behavior on the Aberrant Behavior Checklist (ABC). Height and weight measurements were collected. Children were classified as FS or no FS based on parent reported intake and mealtime behavior. A 24-hour dietary recall was used to record intake percentages < 80%. Logistic regression and multivariable modeling were used to evaluate clinical correlates with FS. RESULTS: Of 103 children, 45.6% (n = 47) were classified as FS; 54.4% (n = 56) no FS. After adjusting for potential confounders, the odds of FS increased by 1.91 (95% CI: 1.38, 2.64, P < .001) for every half-SD increase in BAMBI total score and by 1.35 (95% CI: 1.05, 1.74, P = .020) for every half-SD increase in ABC Hyperactivity/Noncompliance. No group differences in anthropometrics or nutritional intake were identified. CONCLUSIONS: Food selectivity (FS) in children with ASD was strongly associated with greater severity of disruptive mealtime and hyperactivity/noncompliance behaviors. FS was not associated with anthropometrics or nutritional intake.


Subject(s)
Autism Spectrum Disorder , Humans , Autism Spectrum Disorder/psychology , Autism Spectrum Disorder/epidemiology , Male , Female , Child , Child, Preschool , Prevalence , Feeding Behavior , Food Preferences
7.
J Environ Sci Health B ; 59(5): 223-232, 2024.
Article in English | MEDLINE | ID: mdl-38526555

ABSTRACT

The aim of the present study was to assess the selectivity of herbicides applied in the pre and post-planting of pre-sprouted seedlings (PSS). The experiment was conducted in a greenhouse, using a completely randomized design, with nine treatments and four repetitions. The IACSP95-5000 cultivar was used. The treatments consisted of herbicides applied in five doses as follows: in pre-planting: sulfentrazone, diclosulam, imazapic, and imazapyr, in post-planting: ethoxysulfuron, halosulfuron, 2,4-D and MSMA, and a control treatment without herbicide. Injury symptoms were assessed at 7, 15, 30, 45, 60, 75, and 90 days after application (DAA), height, diameter, number of tillers, chlorophyll A, B, and total chlorophyll at 30, 60, and 90 DAA, leaf area, shoot and root dry mass at 90 DAA. The post-emergent herbicides were considered selective. Pre-planting herbicides reduced the variables assessed at 90 DAA, observed by linear regression for diclosulam and imazapic, and exponential regression for imazapyr. Treatments with sulfentrazone caused few injury symptoms, with subsequent recovery. In addition, all the variables analyzed were equal to control, with the sulfentrazone considered selective for the IACSP95-5000 cultivar.


Subject(s)
Herbicides , Saccharum , Sulfonamides , Triazoles , Chlorophyll , Seedlings , Chlorophyll A
8.
Appl Microbiol Biotechnol ; 108(1): 250, 2024 Mar 02.
Article in English | MEDLINE | ID: mdl-38430417

ABSTRACT

The fungal diglycosidase α-rhamnosyl-ß-glucosidase I (αRßG I) from Acremonium sp. DSM 24697 catalyzes the glycosylation of various OH-acceptors using the citrus flavanone hesperidin. We successfully applied a one-pot biocatalysis process to synthesize 4-methylumbellipheryl rutinoside (4-MUR) and glyceryl rutinoside using a citrus peel residue as sugar donor. This residue, which contained 3.5 % [w/w] hesperidin, is the remaining of citrus processing after producing orange juice, essential oil, and peel-juice. The low-cost compound glycerol was utilized in the synthesis of glyceryl rutinoside. We implemented a simple method for the obtention of glyceryl rutinoside with 99 % yield, and its purification involving activated charcoal, which also facilitated the recovery of the by-product hesperetin through liquid-liquid extraction. This process presents a promising alternative for biorefinery operations, highlighting the valuable role of αRßG I in valorizing glycerol and agricultural by-products. KEYPOINTS: • αRßG I catalyzed the synthesis of rutinosides using a suspension of OPW as sugar donor. • The glycosylation of aliphatic polyalcohols by the αRßG I resulted in products bearing a single rutinose moiety. • αRßG I catalyzed the synthesis of glyceryl rutinoside with high glycosylation/hydrolysis selectivity (99 % yield).


Subject(s)
Acremonium , Hesperidin , Hesperidin/chemistry , Glycerol
9.
Nutrition ; 121: 112364, 2024 May.
Article in English | MEDLINE | ID: mdl-38401195

ABSTRACT

A feeding therapy developed in Brazil integrates aspects from diverse approaches and has increasingly been acknowledged as an adjunctive approach for addressing childhood feeding difficulties. In children, problems with eating are a common issue that affects their nutritional well-being, health, and overall quality of life, and can greatly hinder their social, emotional, and physical growth. In the realm of pediatrics, feeding therapy uses food and nutritional education, interactive games, and activities tailored to age groups and individualized treatment plans. The primary objective is to transform mealtime experiences and gradually foster children's acceptance of previously rejected foods. However, this treatment approach is new and recent in Brazil and lacks studies that explore and elucidate the topic. Therefore, this report aims to describe the follow-up and effects of feeding therapy in a 3-y and 8-mo-old neurotypical male patient with feeding difficulties who underwent feeding therapy conducted by a dietitian over a period of 19 wk. The feeding therapy consisted of 45-min sessions once a week in which food and nutrition education activities, games, and interactive activities, personalized according to the treatment plan, were carried out. The effects of feeding therapy were evaluated according to the patient's feeding progression throughout the sessions and their stepwise progress in the eating hierarchy. Based on our observations, the findings of this study suggest that feeding therapy practiced in Brazil can be a viable treatment approach for addressing feeding difficulties within this population. The feeding therapy originated in Brazil stands out from traditional nutritional care with its nurturing and compassionate approach that prioritizes respect for the child.


Subject(s)
Feeding Behavior , Quality of Life , Humans , Child , Male , Feeding Behavior/psychology , Emotions , Health Education , Food
10.
Neotrop Entomol ; 53(2): 383-390, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38228816

ABSTRACT

Reduced-risk insecticides and mirid predators have been used to control Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) in tomato crops. However, even when causing low mortality to the beneficial insects, these products might cause side effects. This study investigated the sublethal and transgenerational effects of buprofezin, cyantraniliprole, and spiromesifen on Macrolophus basicornis (Stal) (Hemiptera: Miridae). After 72 h of exposure of third-instar nymphs and adults to residues on tomato leaves, adult couples were formed and kept in cages with residue-free tomato leaves. The leaves were changed every 48 h and the offspring were assessed in 6 different periods. Body size was assessed by measuring the hind-tibia length of adults (F0) from exposed nymphs and in three different offspring groups. None of the insecticide residues caused a reduction on offspring populations or affected the body size of adults in generation F0. Regardless, buprofezin and spiromesifen reduced the tibia length of adults (F1) from exposed nymphs assayed in the third mating period. Cyantraniliprole did not affect any parameter and could be recommended for control of B. tabaci in association with M. basicornis releases. This study may contribute to future field assays of the compatibility of these insecticides with M. basicornis.


Subject(s)
Hemiptera , Heteroptera , Insecticides , Pyrazoles , Solanum lycopersicum , Spiro Compounds , Thiadiazines , ortho-Aminobenzoates , Animals , Insecticides/pharmacology , Nymph
11.
Exp Appl Acarol ; 92(1): 27-39, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37985607

ABSTRACT

Multiple arthropod pests can affect the same crop in agricultural systems, requiring the integration of control methods. In the present study, the effects of residual exposure to four broad-spectrum insecticides/acaricides (azadiractin, abamectin, chlorfenapyr, and fenpyroximate) on immature (development and survival time) and adult females (longevity, fecundity, and fertility life table parameters) of the predatory mite Neoseiulus barkeri were evaluated. Additionally, the insecticides/acaricides were categorized according to their selectivity based on the classification proposed by the International Organization for Biological Control (IOBC) for assessing the susceptibility of arthropods in laboratory experiments. Method 004, proposed by the Insecticide Resistance Action Committee (IRAC), was adopted for the bioassays with predators exposed to insecticide-acaricide residues. Among the insecticides/acaricides studied, azadirachtin had minimal effects on immature and adult N. barkeri (all non-significant) and was considered harmless based on the classification of toxicity according to the standards/categories proposed by the IOBC. All other insecticides/acaricides affected immature and adult N. barkeri and were considered slightly harmful in terms of toxicity, according to the IOBC.


Subject(s)
Acaricides , Insecticides , Mites , Pesticides , Female , Animals , Acaricides/toxicity , Pesticides/pharmacology , Insecticides/pharmacology , Fertility , Predatory Behavior
12.
FEBS J ; 291(5): 865-883, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37997610

ABSTRACT

Mastoparans are cationic peptides with multifunctional pharmacological properties. Mastoparan-R1 and mastoparan-R4 were computationally designed based on native mastoparan-L from wasps and have improved therapeutic potential for the control of bacterial infections. Here, we evaluated whether these peptides maintain their activity against Escherichia coli strains under a range of salt concentrations. We found that mastoparan-R1 and mastoparan-R4 preserved their activity under the conditions tested, including having antibacterial activities at physiological salt concentrations. The overall structure of the peptides was investigated using circular dichroism spectroscopy in a range of solvents. No significant changes in secondary structure were observed (random coil in aqueous solutions and α-helix in hydrophobic and anionic environments). The three-dimensional structures of mastoparan-R1 and mastoparan-R4 were elucidated through nuclear magnetic resonance spectroscopy, revealing amphipathic α-helical segments for Leu3-Ile13 (mastoparan-R1) and Leu3-Ile14 (mastoparan-R4). Possible membrane-association mechanisms for mastoparan-R1 and mastoparan-R4 were investigated through surface plasmon resonance and leakage studies with synthetic POPC and POPC/POPG (4:1) lipid bilayers. Mastoparan-L had the highest affinity for both membrane systems, whereas the two analogs had weaker association, but improved selectivity for lysing anionic membranes. This finding was also supported by molecular dynamics simulations, in which mastoparan-R1 and mastoparan-R4 were found to have greater interactions with bacteria-like membranes compared with model mammalian membranes. Despite having a few differences in their functional and structural profiles, the mastoparan-R1 analog stood out with the highest activity, greater bacteriostatic potential, and selectivity for lysing anionic membranes. This study reinforces the potential of mastoparan-R1 as a drug candidate.


Subject(s)
Intercellular Signaling Peptides and Proteins , Peptides , Animals , Peptides/pharmacology , Wasp Venoms/pharmacology , Escherichia coli , Sodium Chloride , Computers , Mammals
13.
Future Med Chem ; 16(1): 11-26, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38084595

ABSTRACT

Aim: Our objective was to investigate the trypanocidal effect of the chalcone (2E,4E)-1-(2-hydroxy-3,4,6-trimethoxyphenyl)-5-phenylpenta-2,4-dien-1-one (CPNC). Material & methods: Cytotoxicity toward LLC-MK2 host cells was assessed by MTT assay, and the effect on Trypanosoma cruzi life forms (epimastigotes, trypomastigotes and amastigotes) was evaluated by counting. Flow cytometry analysis was performed to evaluate the possible mechanisms of action. Finally, molecular docking simulations were performed to evaluate interactions between CPNC and T. cruzi enzymes. Results: CPNC showed activity against epimastigote, trypomastigote and amastigote life forms, induced membrane damage, increased cytoplasmic reactive oxygen species and mitochondrial dysfunction on T. cruzi. Regarding molecular docking, CPNC interacted with both trypanothione reductase and TcCr enzymes. Conclusion: CPNC presented a trypanocidal effect, and its effect is related to oxidative stress, mitochondrial impairment and necrosis.


Subject(s)
Chagas Disease , Chalcones , Trypanocidal Agents , Trypanosoma cruzi , Humans , Chalcones/pharmacology , Molecular Docking Simulation , Chagas Disease/drug therapy , Reactive Oxygen Species , Trypanocidal Agents/pharmacology
14.
Braz. j. biol ; 84: e270451, 2024. tab
Article in English | VETINDEX | ID: biblio-1420705

ABSTRACT

Phytophagous mites are dangerous pests, causing economic losses to the world's crops. Nanotechnology is a promising field for pests and disease management, and enhancement of agricultural productivity. The aim of the study was to evaluation of the effectiveness of copper nanoparticles (CuNP) against all stages of eriophyid mite, the citrus rust mite, Phyllocoptruta oleivora (Ashmead) (Acari: Eriophyidae) and tetranychid mite, the citrus brown mite Eutetranychus orientalis (Klein) (Acari: Tetranychidae), and Tenuipalpid mite, the false spider mite, Brevipalpus obovatus Donnadieu (Acari: Tenuipalpidae). This includes its impacts on predacious mites, Amblyseius swirskii Athias-Henriot and Euseius scutalis (Athias-Henriot) (Acari: Phytoseiidae), on orange trees under field conditions. Five different concentrations of copper nanoparticles (40, 80, 160, 240, and 320 ppm), as well as the control (well water) were examined. The obtained results indicated that the mortality rate of both phytophagous and predacious mites was associated with an increase in the concentrations of copper nanoparticles. Copper nanoparticles were significantly effective in killing P. oleivora, E. orientalis and B. obovatus with minimal effects on A. swirskii and E. scutalis. The mortality percentage was 15.24, 20.32, 46.32, 78.97 and 86.37% for P. oleivora, 6.87, 9.86, 28.91, 56.30 and 77.52% for E. orientalis and 8.38, 23.50, 48.83, 68.80 and 84.08% for B. obovatus while the mortality percentage was 0.00, 0.56, 5.83, 9.91 and 15.19% for A. swirskii and 0.44, 3.96, 6.93, 8.63 and 21.39% for E. scutalis one week after exposure to 40, 80, 160, 240 and 320 ppm of copper nanoparticles, respectively. Moreover, the results showed that copper nanoparticles caused a reduction in the percentage of eggs hatching. The percentages of larvae hatching from eggs were 96.29, 80.00, 64.13, 45.66 and 32.17% for P. oleivora, 97.38, 83.28, 69.41, 48.01 and 35.29 for E. orientalis and 96.60, 76.92, 56.38, 40.55 and 33.28% for B. obovatus one week after exposure to copper nanoparticles at 40, 80, 160, 240 and 320 ppm respectively, compared with the control (well water). According to the results, the use of copper nanoparticles significant effect on reducing the population of phytophagous mites associated with orange trees, with low detrimental effects on predatory mites.


Os ácaros fitófagos são pragas perigosas, causando prejuízos econômicos às lavouras mundiais. A nanotecnologia é um campo promissor para o manejo de pragas e doenças, aumentando a produtividade agrícola. O objetivo do presente estudo foi avaliar a eficácia de nanopartículas de cobre (CuNP) em laranjeiras em condições de campo, contra todos os estágios das seguintes espécies: o ácaro eriofídeo, também chamado de ácaro da falsa ferrugem dos citros, ou Phyllocoptruta oleivora (Ashmead) (Acari: Eriophyidae); o ácaro tetraniquídeo, também chamado de ácaro marrom dos citros, ou Eutetranychus orientalis (Klein) (Acari: Tetranychidae); e o ácaro Tenuipalpidae, também chamado de falso ácaro, ou Brevipalpus obovatus (Donnadieu) (Acari: Tenuipalpidae). Isso inclui seus impactos sobre ácaros predadores, como o Amblyseius swirskii Athias-Henriot e o Euseius scutalis (Athias-Henriot) (Acari: Phytoseiidae). Foram examinadas cinco diferentes concentrações de nanopartículas de cobre (40, 80, 160, 240 e 320 ppm), assim como o controle (água de poço). Os resultados obtidos indicaram que a taxa de mortalidade de ácaros fitófagos e predadores esteve associada ao aumento das concentrações de nanopartículas de cobre. As nanopartículas de cobre foram significativamente eficazes em matar o P. oleivora, o E. orientalis e o B. obovatus, com efeitos mínimos sobre o A. swirskii e o E. scutalis. As porcentagens de mortalidade foram: 15,24, 20,32, 46,32, 78,97 e 86,37% para P. oleivora; 6,87, 9,86, 28,91, 56,30 e 77,52% para E. orientalis; 8,38, 23,50, 48,83, 68,80 e 84,08% para B. obovatus; 0,00, 0,56, 5,83, 9,91 e 15,19% para A. swirskii; e 0,44, 3,96, 6,93, 8,63 e 21,39% para E. scutalis, uma semana após a exposição a 40, 80, 160, 240 e 320 ppm de nanopartículas de cobre, respectivamente. Além disso, os resultados mostraram que as nanopartículas de cobre causaram uma redução na porcentagem de eclosão dos ovos. As porcentagens de larvas eclodindo dos ovos foram: 96,29, 80,00, 64,13, 45,66 e 32,17% para P. oleivora; 97,38, 83,28, 69,41, 48,01 e 35,29 para E. orientalis; e 96,60, 76,92, 56,38, 40,58 e 33,29 para B. obovatus, uma semana após a exposição às nanopartículas de cobre a 40, 80, 160, 240 e 320 ppm, respectivamente, em comparação com o controle (água de poço). De acordo com os resultados, o uso de nanopartículas de cobre teve efeito significativo na redução da população de ácaros fitófagos associados às laranjeiras, com baixo efeito prejudicial aos ácaros predadores.


Subject(s)
Copper , Citrus sinensis/parasitology , Nanoparticles , Mites/drug effects
15.
Braz. j. biol ; 84: e261262, 2024. tab, graf, ilus
Article in English | VETINDEX | ID: biblio-1384101

ABSTRACT

Promising bioactivities of silver nanoparticles SNP urged researchers of different specialties to evaluate their field-respective activities. Bioactivity towards agricultural pests were the subject of limited publications. In the current study, SNP were synthesized and miticidal activity was evaluated towards old world date mite Oligonychus afrasiaticus (McGregor) (Acari: Tetranychidae) and an associated predatory mite Neoseiulus barkeri Hughes (Phytoseiidae). Under laboratory conditions, SNP displayed significantly higher activity towards O. afrasiaticus (LC50 was 39.7 µg/mL) than N. barkeri (LC50 was 1587.9 µg/mL) which accounts for about 40 folds of selectivity against the pest. SNP exhibited ovicidal activity against laid eggs of O. afrasiaticus (LC50 was 67.8 µg/mL). In field, SNP (at 216 µg/mL) achieved slightly higher efficiency than in laboratory study, 86.5% of population reduction of O. afrasiaticus was achieved and only 18.5% of N. barkeri population was affected. SNP suppressed hatching of 57.1% of laid eggs of O. afrasiaticus. Residues of silver were determined using ICP-OES spectrometry. Initial residues reached 1.83 µg/mL after application then declined with time passing. Estimated daily intake (EDI) reached 1.28 µg/kg/day, calculated for the highest residues obtained and the highest consumption rate of date in the world. Hazard index (Hi) was 0.17 in average. The obtained level of residues appeared to be safe in terms of acute and chronic toxicity references.


Bioatividades promissoras de nanopartículas de prata (SNPs) incitaram pesquisadores de diferentes especialidades a avaliar suas atividades em campo. A bioatividade contra pragas agrícolas foi objeto de publicações limitadas. No presente estudo, SNPs foram sintetizadas, e a atividade miticida foi avaliada em relação ao ácaro Oligonychus afrasiaticus (McGregor) (Acari: Tetranychidae) e um ácaro predador associado, Neoseiulus barkeri Hughes (Phytoseiidae). Em condições de laboratório, SNP apresentou atividade significativamente maior para O. afrasiaticus (LC50 foi de 39,7 µg/mL) do que N. barkeri (LC50 foi de 1.587,9 µg/mL), o que representa cerca de 40 vezes de seletividade contra a praga. O SNP exibiu atividade ovicida contra ovos postos de O. afrasiaticus (LC50 foi de 67,8 µg/mL). Em campo, o SNP (a 216 µg/mL) alcançou eficiência ligeiramente maior do que em estudo de laboratório; 86,5% de redução populacional de O. afrasiaticus foram alcançados e apenas 18,5% da população de N. barkeri foram afetados. O SNP suprimiu a eclosão de 57,1% dos ovos postos de O. afrasiaticus. Os resíduos de prata foram determinados usando espectrometria ICP-OES. Os resíduos iniciais atingiram 1,83 µg/mL após a aplicação e depois diminuíram com o passar do tempo. A ingestão diária estimada (IDE) atingiu 1,28 µg/kg/dia, calculada para os maiores resíduos obtidos e a maior taxa de consumo de tâmaras do mundo. O índice de risco (Hi) foi de 0,17 em média. O nível de resíduos obtido mostrou-se seguro em termos de referências de toxicidade aguda e crônica.


Subject(s)
Animals , Silver , Pest Control , Agricultural Pests , Tetranychidae , Nanoparticles/administration & dosage , Mites
16.
Braz. j. biol ; 842024.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469327

ABSTRACT

Abstract The aim objective of this study was to determine the trophic ecology of juvenile and adult Acestrorhynchus falcirostris during the rising and flood (high-water) period in six island lakes adjacent to the Solimões River. As such, we investigated: i) the trophic position, through the fractional trophic niche; ii) the niche breadth; iii) niche overlap and iv) the food strategy of the species. The specimens were collected during the years 2014 to 2017, using gillnets with mesh sizes ranging from 30 to 120mm between opposite knots. Through the analysis of stomach contents, the preference in the consumption of items of animal origin was observed. Juveniles consumed insects in greater proportions (IAi% = 50%), while adults consumed fish (IAi%=99,98%). Despite the large supply of food items available in the high-water period, juveniles were the only ones to consume items of allochthonous origin, such as insects. Juveniles presented a different dietary strategy and dietary composition to adults. Juveniles were omnivores with a generalist strategy, while adults were piscivores with a specialist strategy. Thus, the food composition, niche breadth, trophic position and feeding strategy of Acestrorhynchus falcirostris change due to the stage of development.


Resumo O objetivo deste estudo foi determinar a ecologia trófica de juvenis e adultos de Acestrorhynchus falcirostris durante o período de enchente e cheia em seis lagos de ilha adjacentes ao rio Solimões. Assim, investigamos: i) a posição trófica, através do nicho trófico fracional; ii) a largura de nicho; iii) sobreposição de nicho; iv) a estratégia alimentar. Os espécimes foram coletados durante os anos de 2014 a 2017, utilizando redes de emalhar com malha variando de 30 a 120mm entre nós opostos. Por meio da análise do conteúdo estomacal, observamos a preferência no consumo de itens de origem animal. Os juvenis consumiram insetos em maiores proporções (IAi% = 50%), enquanto os adultos consumiram preferencialmente peixes (IAi% = 99,98%). Apesar da grande oferta de alimentos disponíveis no período da cheia, os juvenis eram os únicos a consumir itens de origem alóctone, como por exemplo, os insetos. Os juvenis apresentaram uma estratégia alimentar e composição alimentar diferente para os adultos. Os juvenis foram considerados onívoros com uma estratégia generalista, enquanto os adultos foram considerados piscívoros com uma estratégia alimentar mais especialista. Assim, a composição alimentar, amplitude do nicho, posição trófica e a estratégia alimentar de Acestrorhynchus falcirostris muda em função do estágio de desenvolvimento.

17.
Braz. j. biol ; 84: e253852, 2024. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1355905

ABSTRACT

Abstract The aim objective of this study was to determine the trophic ecology of juvenile and adult Acestrorhynchus falcirostris during the rising and flood (high-water) period in six island lakes adjacent to the Solimões River. As such, we investigated: i) the trophic position, through the fractional trophic niche; ii) the niche breadth; iii) niche overlap and iv) the food strategy of the species. The specimens were collected during the years 2014 to 2017, using gillnets with mesh sizes ranging from 30 to 120mm between opposite knots. Through the analysis of stomach contents, the preference in the consumption of items of animal origin was observed. Juveniles consumed insects in greater proportions (IAi% = 50%), while adults consumed fish (IAi%=99,98%). Despite the large supply of food items available in the high-water period, juveniles were the only ones to consume items of allochthonous origin, such as insects. Juveniles presented a different dietary strategy and dietary composition to adults. Juveniles were omnivores with a generalist strategy, while adults were piscivores with a specialist strategy. Thus, the food composition, niche breadth, trophic position and feeding strategy of Acestrorhynchus falcirostris change due to the stage of development.


Resumo O objetivo deste estudo foi determinar a ecologia trófica de juvenis e adultos de Acestrorhynchus falcirostris durante o período de enchente e cheia em seis lagos de ilha adjacentes ao rio Solimões. Assim, investigamos: i) a posição trófica, através do nicho trófico fracional; ii) a largura de nicho; iii) sobreposição de nicho; iv) a estratégia alimentar. Os espécimes foram coletados durante os anos de 2014 a 2017, utilizando redes de emalhar com malha variando de 30 a 120mm entre nós opostos. Por meio da análise do conteúdo estomacal, observamos a preferência no consumo de itens de origem animal. Os juvenis consumiram insetos em maiores proporções (IAi% = 50%), enquanto os adultos consumiram preferencialmente peixes (IAi% = 99,98%). Apesar da grande oferta de alimentos disponíveis no período da cheia, os juvenis eram os únicos a consumir itens de origem alóctone, como por exemplo, os insetos. Os juvenis apresentaram uma estratégia alimentar e composição alimentar diferente para os adultos. Os juvenis foram considerados onívoros com uma estratégia generalista, enquanto os adultos foram considerados piscívoros com uma estratégia alimentar mais especialista. Assim, a composição alimentar, amplitude do nicho, posição trófica e a estratégia alimentar de Acestrorhynchus falcirostris muda em função do estágio de desenvolvimento.


Subject(s)
Animals , Rivers , Characiformes , Seasons , Lakes , Ecosystem , Food Chain , Fishes , Gastrointestinal Contents
18.
Audiol., Commun. res ; 29: e2848, 2024. tab
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1564008

ABSTRACT

RESUMO Objetivo verificar o risco de distúrbio alimentar pediátrico em pré-escolares que nasceram prematuros e relacionar com os aspectos neonatais, de aleitamento materno e de hábitos orais. Métodos estudo descritivo e longitudinal. A amostra foi composta por pré-escolares que nasceram prematuros e que foram acompanhados até os 24 meses de idade corrigida. A coleta de dados consistiu em análise de prontuários, entrevista e aplicação da Escala Brasileira de Alimentação Infantil. Resultados participaram 19 pré-escolares, com média de idade de 5 anos e 1 mês, nascidos prematuros (idade gestacional de 32 semanas), saudáveis e com função motora oral normal aos 2 anos de idade corrigida. A aplicação da escala permitiu identificar risco de distúrbio alimentar pediátrico em 31,57% da amostra. Não houve diferença entre os grupos com e sem risco do distúrbio quanto às variáveis neonatais, de aleitamento materno e de hábitos orais. Apenas a variável tempo de transição alimentar no período de internação neonatal apresentou diferença entre os grupos, sendo maior em crianças que não apresentaram risco para o distúrbio. Conclusão O risco de distúrbio alimentar pediátrico ocorreu em quase um terço dos prematuros em idade pré-escolar. O tempo de transição alimentar no período de internação neonatal foi a única variável que apresentou diferença entre os grupos com e sem risco para o distúrbio. Assim, pode-se refletir que o momento de introdução da alimentação oral e a forma de progressão da dieta até a via oral plena na internação neonatal podem ter relação com o comportamento alimentar em outras fases do desenvolvimento infantil.


ABSTRACT Purpose To verify the risk of pediatric eating disorders in preschoolers who were born prematurely and relate it to neonatal aspects, breastfeeding and oral habits. Methods Descriptive and longitudinal study. The sample was made up of preschoolers who were born prematurely and who were followed up until 24 months of corrected age. Data collection consisted of analysis of medical records, interviews and application of the Brazilian Infant Feeding Scale (EBAI). Results 19 preschoolers participated, with a mean age of 5.11±0.51, born prematurely (gestational age of 32.05 ± 3.26 weeks), healthy and with normal oral motor function at 2 years of corrected age. The application of the EBAI made it possible to identify the risk of pediatric eating disorders in 31.57% of the sample. There was no difference between the groups with and without risk of pediatric eating disorders regarding neonatal variables, breastfeeding and oral habits. Only the variable feeding time during the neonatal hospitalization period showed a difference between the groups, being higher in children who were not at risk for pediatric eating disorders. Conclusion The risk of pediatric eating disorders occurred in almost a third of pre-school-age premature infants. The dietary transition time during the neonatal hospitalization period was the only variable that showed a difference between the groups with and without risk of pediatric eating disorders. Thus, one may consider that, the moment of introduction of oral feeding and the way in which the diet progresses until the full oral route, during neonatal hospitalization, may be related to eating behavior in other phases of child development.

19.
Mundo Saúde (Online) ; 48: e15292023, 2024.
Article in English, Portuguese | LILACS-Express | LILACS | ID: biblio-1527499

ABSTRACT

Dificuldade alimentar é todo problema que afeta negativamente o processo dos pais ou cuidadores de suprirem alimento ou nutrientes à criança. O objetivo deste trabalho foi investigar as dificuldades alimentares em pré-escolares de uma escola municipal de educação infantil de Uruguaiana/RS. O estudo foi aprovado pelo Comitê de Ética em Pesquisa e realizado entre outubro e novembro de 2022. Foram convidadas a participar da pesquisa todos os pais ou responsáveis das crianças (n=70) que frequentavam a escola, na faixa etária de 4-5 anos. Todos receberam o Termo de Consentimento Livre e Esclarecido, bem como o questionário de pesquisa. O instrumento utilizado foi a Escala Brasileira de Alimentação Infantil (EBAI), que possui 14 perguntas referentes à alimentação das crianças. Foi realizada estatística descritiva, em termos de frequência e realizada análise de variância (ANOVA) para comparações entre os sexos (p<0,05). Foram obtidas 31 respostas dos pais relativas à alimentação das crianças. Os dados revelaram que 9,68% (n=3) possuíam algum grau de dificuldade alimentar, sendo 3,33% (n=1) com grau severo e 6,45% (n=2) com grau moderado. As demais crianças (n=28) também apresentaram comportamentos relacionados às dificuldades alimentares, porém, sem pontuação suficiente para serem classificadas com dificuldade alimentar. Os comportamentos mais frequentemente descritos foram: o responsável usar distrações ou ir atrás da criança para que ela coma, tempo de a alimentação em torno de 31-60min ou mais, criança que nauseia, cospe ou vomita com algum tipo de alimento e a influência negativa da alimentação nas relações familiares. Desta forma, observou-se um baixo percentual de dificuldades alimentares na população estudada, de acordo com a literatura estudada.


Feeding difficulties are any problem that negatively affects the process of parents or caregivers providing food or nutrients to the child. The objective of this work was to investigate eating difficulties in preschool children at a municipal early childhood education school in Uruguaiana/RS. The study was approved by the Research Ethics Committee and carried out between October and November 2022. All parents or guardians of children (n=70) who attended school, aged 4-5 years, were invited to participate in the research. Everyone received the Free and Informed Consent Form, as well as the research questionnaire. The instrument used was the Brazilian Infant Feeding Scale (EBAI), which has 14 questions regarding children's nutrition. Descriptive statistics were performed in terms of frequency and analysis of variance (ANOVA) was performed for comparisons between sexes (p<0.05). 31 responses were obtained from parents regarding children's nutrition. The data revealed that 9.68% (n=3) had some degree of feeding difficulty, 3.33% (n=1) with a severe degree and 6.45% (n=2) with a moderate degree. The remaining children (n=28) also presented behaviors related to feeding difficulties, however, without enough scores to be classified as having feeding difficulties. The most frequently described behaviors were: the caregiver using distractions or going after the child to make them eat, feeding time around 31-60 minutes or more, child who nauseates, spits or vomits with some type of food and the negative influence of food in family relationships. Thus, a low percentage of feeding difficulties was observed in the studied population, in accordance with the literature studied.

20.
Curr Drug Deliv ; 2023 Nov 27.
Article in English | MEDLINE | ID: mdl-38013438

ABSTRACT

Glioblastoma multiforme is the most common and aggressive malignant tumor that affects the central nervous system, with high mortality and low survival. Glioblastoma multiforme treatment includes resection tumor surgery, followed by radiotherapy and chemotherapy adjuvants. However, the drugs used in chemotherapy present some limitations, such as the difficulty of crossing the bloodbrain barrier and resisting the cellular mechanisms of drug efflux. The use of polymeric nanoparticles has proven to be an effective alternative to circumvent such limitations, as it allows the exploration of a range of polymeric structures that can be modified in order to control the biodistribution and cytotoxic effect of the drug delivery systems. Nanoparticles are nanometric in size and allow the incorporation of targeting ligands on their surface, favoring the transposition of the blood-brain barrier and the delivery of the drug to specific sites, increasing the selectivity and safety of chemotherapy. The present review has described the characteristics of chitosan, poly(vinyl alcohol), poly(lactic-coglycolic acid), poly(ethylene glycol), poly(ß-amino ester), and poly(ε-caprolactone), which are some of the most commonly used polymers in the manufacture of nanoparticles for the treatment of glioblastoma multiforme. In addition, some of the main targeting ligands used in these nanosystems are presented, such as transferrin, chlorotoxin, albumin, epidermal growth factor, and epidermal growth factor receptor blockers, explored for the active targeting of antiglioblastoma agents.

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