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1.
Braz. j. biol ; 84: e253215, 2024. tab
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1360216

RESUMO

Abstract Frequencies, magnitudes, and distributions of occurrence can affect the events. The problem can be worse or the solution better if greater frequencies and magnitudes are presented with aggregated distribution in the production system. Indices, hence, are used to assist in decision-making on certain issues. The system formed by Caryocar brasiliense Camb. (Malpighiales: Caryocaraceae), a typical and economically important Brazilian Cerrado tree species, and its several arthropods are adequate to evaluate a new index. This study aimed to test an index to identify the loss and solution sources and their importance in the system's loss or income gain. The index is: Percentage of Importance Indice % I . I . = k s 1 × c 1 × d s 1 / Σ k s 1 × c 1 × d s 1 + k s 2 × c 2 × d s 2 + k s n × c n × d s n x 100. T h e % I . I . separated the loss sources [e.g., Edessa rufomarginata De Geer, 1773 (Hemiptera: Pentatomidae) on fruits = 41.90%)] on the percentage of reduction of fruit production (e.g., 0.13%), calculated the attention level (e.g., 0.10/fruit), with a total lost production of 1.35% (≈ 307 total lost fruits). The % I.I. also separated the solution sources [e.g., Zelus armillatus (Lep. and Servi., 1825) (Hemiptera: Reduviidae) = 55.48%), the non-attention level (e.g., Z. armillatus: 0.394 for E. rufomarginata on fruit), with total income gain of 0.56% (≈ 128 total saved fruits) on the natural system (e.g., C. brasiliense trees). This index can calculate losses or the effectiveness of the solutions monetarily. Here I test the % I.I., an index that can detect the key loss and solution sources on the system, which can be applied in some knowledge areas.


Resumo Frequências, magnitudes e distribuição de ocorrência pode afetar os eventos. O problema pode ser pior ou a solução melhor se maiores frequências e magnitudes forem apresentadas com distribuição agregada no sistema de produção. Índices, então, são usados para assistir na decisão de certas questões. O sistema formado pelo Caryocar brasiliense Camb. (Malpighiales: Caryocaraceae), uma espécie arbórea típica e economicamente importante do Cerrado brasileiro, e seus diversos artrópodes são adequados para avaliar um novo índice. A motivação deste trabalho foi testar um índice capaz de identificar as fontes de perda e de soluções, e suas importâncias em termos de perdas ou ganhos no sistema. O índice é: percentagem de importância % I . I . = k s 1 × c 1 × d s 1 / Σ k s 1 × c 1 × d s 1 + k s 2 × c 2 × d s 2 + k s n × c n × d s n x 100. O % I . I . separou as fontes de perda [ex., Edessa rufomarginata De Geer, 1773 (Hemiptera: Pentatomidae) em frutos = 41,90%)] na percentagem de redução na produção de frutos (ex., 0,13%), calculando o nível de atenção (ex., 0,10/fruto), com um total de perda de produção de 1,35% (≈ 307 frutos totais perdidos). O % I.I. também separou as fontes de solução [ex., Zelus armillatus (Lep. and Servi., 1825) (Hemiptera: Reduviidae) = 55,48%)], o nível de não atenção (ex., Z. armillatus: 0,394 para E. rufomarginata em fruto), com total de ganho de 0,56% (≈ 128 total de frutos salvos) no sistema natural (ex., árvores de C. brasiliense). Esse índice pode calcular essas perdas ou a eficácia das soluções monetariamente. Aqui eu testo o % I.I., um índice capaz de detectar fatores chaves de perda e de soluções no sistema, capaz de ser aplicado em algumas áreas do conhecimento.

2.
Braz. j. biol ; 84: e253218, 2024. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355863

RESUMO

Abstract Indices are used to help on decision-making. This study aims to develop and test an index, which can determine the loss (e.g., herbivorous insects) and solution (e.g., natural enemies) sources. They will be classified according to their importance regarding the ability to damage or to reduce the source of damage to the system when the final production is unknown. Acacia auriculiformis (Fabales: Fabaceae), a non-native pioneer species in Brazil with fast growth and rusticity, is used in restoration programs, and it is adequate to evaluate a new index. The formula was: Percentage of the Importance Indice-Production Unknown (% I.I.-PU) = [(ks1 x c1 x ds1)/Σ (ks1 x c1 x ds1) + (ks2 x c2 x ds2) + (ksn x cn x dsn)] x 100. The loss sources Aethalion reticulatum L., 1767 (Hemiptera: Aethalionidae), Aleyrodidae (Hemiptera), Stereoma anchoralis Lacordaire, 1848 (Coleoptera: Chrysomelidae), and Tettigoniidae, and solution sources Uspachus sp. (Araneae: Salticidae), Salticidae (Araneae), and Pseudomyrmex termitarius (Smith, 1877) (Hymenoptera: Formicidae) showed the highest % I.I.-PU on leaves of A. auriculiformis saplings. The number of Diabrotica speciosa Germar, 1824 (Coleoptera: Chrysomelidae) was reduced per number of Salticidae; that of A. reticulatum that of Uspachus sp.; and that of Cephalocoema sp. (Orthoptera: Proscopiidae) that of P. termitarius on A. auriculiformis saplings. However, the number of Aleyrodidae was increased per number of Cephalotes sp. (Hymenoptera: Formicidae) and that of A. reticulatum that of Brachymyrmex sp. (Hymenoptera: Formicidae) on A. auriculiformis saplings. The A. reticulatum damage was reduced per number of Uspachus sp., but the Aleyrodidae damage was increased per number of Cephalotes sp., totaling 23.81% of increase by insect damages on A. auriculiformis saplings. Here I show and test the % I.I.-PU. It is an new index that can detect the loss or solution sources on a system when production is unknown. It can be applied in some knowledge areas.


Resumo Índices são usados para ajudar na tomada de decisões. Este trabalho teve como objetivo desenvolver e testar um índice capaz de determinar fontes de perda (ex.: insetos herbívoros) e de solução (ex.: inimigos naturais). Eles serão classificados de acordo com sua importância quanto a habilidade de danificar ou reduzir danos no sistema, quando a produção final é desconhecida. Acacia auriculiformis (Fabales: Fabaceae), uma espécie pioneira não nativa do Brasil com rápido crescimento e rusticidade, usada em programas de restauração, é adequada para avaliar um novo índice. A fórmula foi: Porcentagem de Índice de Importância-Produção Desconhecida (% I.I.-PD) = [(ks1 x c1 x ds1)/Σ (ks1 x c1 x ds1) + (ks2 x c2 x ds2) + (ksn x cn x dsn)] x 100. As fontes de perda Aethalion reticulatum L., 1767 (Hemiptera: Aethalionidae), Aleyrodidae (Hemiptera), Stereoma anchoralis Lacordaire, 1848 (Coleoptera: Chrysomelidae) e Tettigoniidae, e as fontes de solução Uspachus sp. (Araneae: Salticidae), Salticidae (Araneae) e Pseudomyrmex termitarius (Smith, 1877) (Hymenoptera: Formicidae) apresentaram maiores % I.I.-PD nas folhas das mudas de A. auriculiformis. O número de Diabrotica speciosa Germar, 1824 (Coleoptera: Chrysomelidae) foi reduzido pelo número de Salticidae; o de A. reticulatum pelo de Uspachus sp.; e o de Cephalocoema sp. (Orthoptera: Proscopiidae) pelo de P. termitarius em mudas de A. auriculiformis. Entretanto, o número de Aleyrodidae foi aumentado pelo número de Cephalotes sp. (Hymenoptera: Formicidae) e o de A. reticulatum pelo de Brachymyrmex sp. (Hymenoptera: Formicidae) em mudas de A. auriculiformis. O dano de A. reticulatum foi reduzido pelo número de Uspachus sp., mas o dano de Aleyrodidae foi aumentado pelo número de Cephalotes sp., totalizando 23,81% de aumento de danos em mudas de A. auriculiformis. Aqui eu apresento e testo o % I.I.-PD. Ele é um novo índice capaz de detectar fontes de perda e de solução no sistema quando não se conhece a produção final. Ele pode ser aplicado em algumas áreas do conhecimento.


Assuntos
Animais , Formigas , Besouros , Acacia , Hemípteros , Insetos
3.
Braz. j. biol ; 83: e245536, 2023. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339403

RESUMO

Abstract Acacia mangium (Willd., 1806) (Fabales: Fabaceae) is a fast growing, rustic, pioneer species, with potential to fix nitrogen, and for programs to recover degraded areas. The objective was to evaluate the distribution and the functional diversity of interactions and the K-dominance of arthropod groups on A. mangium saplings. The number of individuals of eleven species of phytophagous insects, three bee species, and fourteen natural enemy species were highest on the adaxial leaf surface of this plant. Abundance, diversity and species richness of phytophagous insects and natural enemies, and abundance and species richness of pollinators were highest on the adaxial A. mangium leaf surface. The distribution of five species of sap-sucking hemipterans and six of protocooperating ants (Hymenoptera), with positive interaction between these groups, and three bee species (Hymenoptera) were aggregated on leaves of A. mangium saplings. Aethalion reticulatum (L.) (Hemiptera: Aethalionidae) and Bemisia sp. (Hemiptera: Aleyrodidae); Brachymyrmex sp. and Camponotus sp. (Hymenoptera: Formicidae); and Trigona spinipes Fabricius (Hymenoptera: Apidae) were the most dominant phytophagous insects, natural enemies, and pollinators, respectively, on A. mangium leaves. Knowledge of preferred leaf surfaces could help integrated pest management programs.


Resumo Acacia mangium (Willd., 1806) (Fabales: Fabaceae) é uma planta pioneira com rápido crescimento, rusticidade, potencial nitrificador e importante em programas de recuperação de áreas degradadas. O objetivo foi avaliar a distribuição e a diversidade funcional das interações e a dominância-K de grupos de artrópodes em árvores jovens de A. mangium. Os números de indivíduos de onze espécies de insetos fitófagos, três de abelhas e quatorze de inimigos naturais foram maiores na superfície adaxial de folhas dessa planta. A abundância, diversidade e riqueza de espécies de insetos fitófagos e inimigos naturais, e a abundância e riqueza de espécies de polinizadores foram maiores na face adaxial de folhas de A. mangium. A distribuição de cinco espécies de hemípteros sugadores de seiva e seis de formigas protocooperantes (Hymenoptera), com interação positiva entre esses grupos, e três de abelhas (Hymenoptera) foi agregada em folhas de plantas jovens de A. mangium. Aethalion reticulatum (L.) (Hemiptera: Aethalionidae) e Bemisia sp. (Hemiptera: Aleyrodidae); Brachymyrmex sp. e Camponotus sp. (Hymenoptera: Formicidae); e Trigona spinipes Fabricius (Hymenoptera: Apidae) foram os insetos fitófagos, inimigos naturais e polinizadores mais dominantes, respectivamente, em folhas de A. mangium. A definição da superfície foliar preferida pode auxiliar programas de manejo integrado de pragas.


Assuntos
Animais , Formigas , Artrópodes , Acacia , Fabaceae , Abelhas , Folhas de Planta
4.
Braz. J. Biol. ; 83: 1-10, 2023. tab
Artigo em Inglês | VETINDEX | ID: vti-765549

RESUMO

Acacia mangium (Willd., 1806) (Fabales: Fabaceae) is a fast growing, rustic, pioneer species, with potential to fix nitrogen, and for programs to recover degraded areas. The objective was to evaluate the distribution and the functional diversity of interactions and the K-dominance of arthropod groups on A. mangium saplings. The number of individuals of eleven species of phytophagous insects, three bee species, and fourteen natural enemy species were highest on the adaxial leaf surface of this plant. Abundance, diversity and species richness of phytophagous insects and natural enemies, and abundance and species richness of pollinators were highest on the adaxial A. mangium leaf surface. The distribution of five species of sap-sucking hemipterans and six of protocooperating ants (Hymenoptera), with positive interaction between these groups, and three bee species (Hymenoptera) were aggregated on leaves of A. mangium saplings. Aethalion reticulatum (L.) (Hemiptera: Aethalionidae) and Bemisia sp. (Hemiptera: Aleyrodidae); Brachymyrmex sp. and Camponotus sp. (Hymenoptera: Formicidae); and Trigona spinipes Fabricius (Hymenoptera: Apidae) were the most dominant phytophagous insects, natural enemies, and pollinators, respectively, on A. mangium leaves. Knowledge of preferred leaf surfaces could help integrated pest management programs.(AU)


Acacia mangium (Willd., 1806) (Fabales: Fabaceae) é uma planta pioneira com rápido crescimento, rusticidade, potencial nitrificador e importante em programas de recuperação de áreas degradadas. O objetivo foi avaliar a distribuição e a diversidade funcional das interações e a dominância-K de grupos de artrópodes em árvores jovens de A. mangium. Os números de indivíduos de onze espécies de insetos fitófagos, três de abelhas e quatorze de inimigos naturais foram maiores na superfície adaxial de folhas dessa planta. A abundância, diversidade e riqueza de espécies de insetos fitófagos e inimigos naturais, e a abundância e riqueza de espécies de polinizadores foram maiores na face adaxial de folhas de A. mangium. A distribuição de cinco espécies de hemípteros sugadores de seiva e seis de formigas protocooperantes (Hymenoptera), com interação positiva entre esses grupos, e três de abelhas (Hymenoptera) foi agregada em folhas de plantas jovens de A. mangium. Aethalion reticulatum (L.) (Hemiptera: Aethalionidae) e Bemisia sp. (Hemiptera: Aleyrodidae); Brachymyrmex sp. e Camponotus sp. (Hymenoptera: Formicidae); e Trigona spinipes Fabricius (Hymenoptera: Apidae) foram os insetos fitófagos, inimigos naturais e polinizadores mais dominantes, respectivamente, em folhas de A. mangium. A definição da superfície foliar preferida pode auxiliar programas de manejo integrado de pragas.(AU)


Assuntos
Animais , Acacia/parasitologia , Hemípteros , Himenópteros , Abelhas
5.
Mol Pharm ; 19(2): 508-519, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-34939811

RESUMO

Using light scattering (LS), small-angle X-ray scattering (SAXS), and coarse-grained Monte Carlo (MC) simulations, we studied the self-interactions of two monoclonal antibodies (mAbs), PPI03 and PPI13. With LS measurements, we obtained the osmotic second virial coefficient, B22, and the molecular weight, Mw, of the two mAbs, while with SAXS measurements, we studied the mAbs' self-interaction behavior in the high protein concentration regime up to 125 g/L. Through SAXS-derived coarse-grained representations of the mAbs, we performed MC simulations with either a one-protein or a two-protein model to predict B22. By comparing simulation and experimental results, we validated our models and obtained insights into the mAbs' self-interaction properties, highlighting the role of both ion binding and charged patches on the mAb surfaces. Our models provide useful information about mAbs' self-interaction properties and can assist the screening of conditions driving to colloidal stability.


Assuntos
Anticorpos Monoclonais , Anticorpos Monoclonais/química , Método de Monte Carlo , Espalhamento a Baixo Ângulo , Difração de Raios X , Raios X
6.
Elife ; 112022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35357307

RESUMO

The biogenesis of eukaryotic ribosomes involves the ordered assembly of around 80 ribosomal proteins. Supplying equimolar amounts of assembly-competent ribosomal proteins is complicated by their aggregation propensity and the spatial separation of their location of synthesis and pre-ribosome incorporation. Recent evidence has highlighted that dedicated chaperones protect individual, unassembled ribosomal proteins on their path to the pre-ribosomal assembly site. Here, we show that the co-translational recognition of Rpl3 and Rpl4 by their respective dedicated chaperone, Rrb1 or Acl4, reduces the degradation of the encoding RPL3 and RPL4 mRNAs in the yeast Saccharomyces cerevisiae. In both cases, negative regulation of mRNA levels occurs when the availability of the dedicated chaperone is limited and the nascent ribosomal protein is instead accessible to a regulatory machinery consisting of the nascent-polypeptide-associated complex and the Caf130-associated Ccr4-Not complex. Notably, deregulated expression of Rpl3 and Rpl4 leads to their massive aggregation and a perturbation of overall proteostasis in cells lacking the E3 ubiquitin ligase Tom1. Taken together, we have uncovered an unprecedented regulatory mechanism that adjusts the de novo synthesis of Rpl3 and Rpl4 to their actual consumption during ribosome assembly and, thereby, protects cells from the potentially detrimental effects of their surplus production.


Living cells are packed full of molecules known as proteins, which perform many vital tasks the cells need to survive and grow. Machines called ribosomes inside the cells use template molecules called messenger RNAs (or mRNAs for short) to produce proteins. The newly-made proteins then have to travel to a specific location in the cell to perform their tasks. Some newly-made proteins are prone to forming clumps, so cells have other proteins known as chaperones that ensure these clumps do not form. The ribosomes themselves are made up of several proteins, some of which are also prone to clumping as they are being produced. To prevent this from happening, cells control how many ribosomal proteins they make, so there are just enough to form the ribosomes the cell needs at any given time. Previous studies found that, in yeast, two ribosomal proteins called Rpl3 and Rpl4 each have their own dedicated chaperone to prevent them from clumping. However, it remained unclear whether these chaperones are also involved in regulating the levels of Rpl3 and Rpl4. To address this question, Pillet et al. studied both of these dedicated chaperones in yeast cells. The experiments showed that the chaperones bound to their target proteins (either units of Rpl3 or Rpl4) as they were being produced on the ribosomes. This protected the template mRNAs the ribosomes were using to produce these proteins from being destroyed, thus allowing further units of Rpl3 and Rpl4 to be produced. When enough Rpl3 and Rpl4 units were made, there were not enough of the chaperones to bind them all, leaving the mRNA templates unprotected. This led to the destruction of the mRNA templates, which decreased the numbers of Rpl3 and Rpl4 units being produced. The work of Pillet et al. reveals a feedback mechanism that allows yeast to tightly control the levels of Rpl3 and Rpl4. In the future, these findings may help us understand diseases caused by defects in ribosomal proteins, such as Diamond-Blackfan anemia, and possibly also neurodegenerative diseases caused by clumps of proteins forming in cells. The next step will be to find out whether the mechanism uncovered by Pillet et al. also exists in human and other mammalian cells.


Assuntos
Proteínas Ribossômicas , Proteínas de Saccharomyces cerevisiae , Proteostase , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
7.
J Surg Res ; 279: 548-556, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35921721

RESUMO

INTRODUCTION: Patients who undergo splenectomy (SPLN) have an estimated 10%-35% risk of venous thromboembolic events; however, the underlying mechanism and strategy for prevention have yet to be identified. The goals of this study were to 1) investigate platelet aggregation after SPLN, 2) examine if aspirin administration could mitigate this effect, and 3) determine if concomitant hemorrhage would affect post-SPLN platelet function and response to aspirin. METHODS: Murine models of operative SPLN and submandibular bleed (SMB) were utilized. Mice were randomized to eight groups as follows: untouched, SPLN, sham (laparotomy only), SMB, SPLN + SMB, SPLN + aspirin (ASA), SMB + ASA, and SPLN + SMB + ASA. Aspirin (50 mg/kg) was administered on postoperative days (PODs) one and two via oral gavage. Mice were euthanized on POD 3, platelet counts were obtained, and blood samples were analyzed via rotational thromboelastometry and impedance aggregometry with adenosine diphosphate (ADP) and arachidonic acid (AA) as agonists. RESULTS: By POD 3, SPLN mice displayed a significant thrombocytosis compared to untouched, SMB, and sham SPLN mice. Clotting time and clot formation time were significantly decreased in SPLN and SPLN + SMB cohorts compared to untouched and sham controls with elevated mean clot firmness. SPLN mice also displayed a significant increase in ADP- and AA-mediated platelet aggregability compared to untouched controls, SMB, and SPLN + SMB. ASA significantly decreased platelet aggregation via both ADP and AA signaling in SPLN and SPLN + SMB cohorts without affecting viscoelastic coagulation testing. CONCLUSIONS: Platelet hyperaggregability after SPLN is mediated by both ADP and AA signaling. Early aspirin administration may prevent increased platelet aggregation exacerbated after polytrauma.

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 282: 121661, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35926287

RESUMO

A novel turn-on fluorescent sensor for hydrogen peroxide (H2O2) was prepared from chitosan (CS) coating mesoporous silica nanoparticles (MSNs) loaded with 1-(4-Aminophenyl)-1,2,2-triphenylethene (TPE-NH2) and silver nanoparticles (AgNCs). The surface of MSNs was coated by CS as the gatekeeper and the template for loading of AgNCs. Because of the surface plasmon-enhanced energy transfer (SPEET), AgNCs effectively quenched the fluorescence emission of nanoparticles. In the presence of H2O2, AgNCs can be oxidized to Ag+, resulting in the recovery of fluorescence. This fluorescent sensor was characterized with respect to its chemical composition, morphological features and optical properties by means of FTIR, XRD, TGA, SEM, TEM, XPS, UV-Vis and fluorescence spectroscopy. The MSN/TPE-CS@Ag nanoparticles showed good sensitivity and selectivity for H2O2 even with various interfering ions and agents. Under optimized conditions, the detection limit for H2O2 was 0.64 µM in the rage of 1-300 µM. The feasibility of the practical application of this probe was confirmed by accurate quantitative of H2O2 in practical samples.

9.
Biosens Bioelectron ; 215: 114582, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35933738

RESUMO

The discriminative detection of glutathione (GSH) from cysteine (Cys) remains a challenge because of their similarity in structure and chemical properties. This study reported a strategy for selective and sensitive detection of GSH based on the GSH-promoted blue fluorescence of UiO-66-NH2 and aggregation-enhanced emission (AEE) feature of orange emissive Cu nanoclusters (NCs). A relatively weak blue fluorescence of UiO-66-NH2 was converted to strong after reacting with GSH due to the rotation-restricted emission enhancement mechanism. In addition, the GSH-activated UiO-66-NH2 was further used as a template and reducing reagent for synthesizing orange-red AEE active Cu NCs composites (UiO-66-NH2@Cu NCs). A ratiometric fluorescence response was observed after forming UiO-66-NH2@Cu NCs, helping discriminate GSH over Cys. In addition, UiO-66-NH2@Cu NCs were further utilized for the detection of GSH in clinical samples. The present findings provide an efficient strategy to discriminate GSH over Cys and open a new door for utilizing and functionalizing metal-organic frameworks (MOFs) for various applications.

10.
Redox Biol ; 55: 102415, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35933901

RESUMO

Alexander disease is a fatal neurological disorder caused by mutations in the intermediate filament protein Glial Fibrillary Acidic Protein (GFAP), which is key for astrocyte homeostasis. These mutations cause GFAP aggregation, astrocyte dysfunction and neurodegeneration. Remarkably, most of the known GFAP mutations imply a change by more nucleophilic amino acids, mainly cysteine or histidine, which are more susceptible to oxidation and lipoxidation. Therefore, we hypothesized that a higher susceptibility of Alexander disease GFAP mutants to oxidative or electrophilic damage, which frequently occurs during neurodegeneration, could contribute to disease pathogenesis. To address this point, we have expressed GFP-GFAP wild type or the harmful Alexander disease GFP-GFAP R239C mutant in astrocytic cells. Interestingly, GFAP R239C appears more oxidized than the wild type under control conditions, as indicated both by its lower cysteine residue accessibility and increased presence of disulfide-bonded oligomers. Moreover, GFP-GFAP R239C undergoes lipoxidation to a higher extent than GFAP wild type upon treatment with the electrophilic mediator 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2). Importantly, GFAP R239C filament organization is altered in untreated cells and is earlier and more severely disrupted than GFAP wild type upon exposure to oxidants (diamide, H2O2) or electrophiles (4-hydroxynonenal, 15d-PGJ2), which exacerbate GFAP R239C aggregation. Furthermore, H2O2 causes reversible alterations in GFAP wild type, but irreversible damage in GFAP R239C expressing cells. Finally, we show that GFAP R239C expression induces a more oxidized cellular status, with decreased free thiol content and increased mitochondrial superoxide generation. In addition, mitochondria show decreased mass, increased colocalization with GFAP and altered morphology. Notably, a GFP-GFAP R239H mutant recapitulates R239C-elicited alterations whereas an R239G mutant induces a milder phenotype. Together, our results outline a deleterious cycle involving altered GFAP R239C organization, mitochondrial dysfunction, oxidative stress, and further GFAP R239C protein damage and network disruption, which could contribute to astrocyte derangement in Alexander disease.

11.
Big Data Cogn Comput ; 6(1)2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35936510

RESUMO

Literature-based discovery (LBD) summarizes information and generates insight from large text corpuses. The SemNet framework utilizes a large heterogeneous information network or "knowledge graph" of nodes and edges to compute relatedness and rank concepts pertinent to a user-specified target. SemNet provides a way to perform multi-factorial and multi-scalar analysis of complex disease etiology and therapeutic identification using the 33+ million articles in PubMed. The present work improves the efficacy and efficiency of LBD for end users by augmenting SemNet to create SemNet 2.0. A custom Python data structure replaced reliance on Neo4j to improve knowledge graph query times by several orders of magnitude. Additionally, two randomized algorithms were built to optimize the HeteSim metric calculation for computing metapath similarity. The unsupervised learning algorithm for rank aggregation (ULARA), which ranks concepts with respect to the user-specified target, was reconstructed using derived mathematical proofs of correctness and probabilistic performance guarantees for optimization. The upgraded ULARA is generalizable to other rank aggregation problems outside of SemNet. In summary, SemNet 2.0 is a comprehensive open-source software for significantly faster, more effective, and user-friendly means of automated biomedical LBD. An example case is performed to rank relationships between Alzheimer's disease and metabolic co-morbidities.

12.
Folia Parasitol (Praha) ; 692022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35938931

RESUMO

Parasitism among individuals in a population often varies more than expected by chance only, leading to parasite aggregation, which is a parameter of paramount importance in parasite population dynamics and particularly in vector-borne epidemiology. However, the origin of this phenomenon is yet not fully elucidated. An increasing body of literature has demonstrated that individuals vary consistently in their behaviour, which is referred to as animal personality. Such behavioural variation could potentially lead to different encounter rates with parasites. To test this hypothesis, the relationship between personality and burden with ticks (Ixodes spp.) in the bank vole, Myodes glareolus (Schreber), was assessed. Wild rodents (eight females and 18 males) were live-trapped, identified, sexed, weighted, and inspected for ticks. Behavioural profiling was then performed using standardised tests measuring activity/exploration and boldness with a combination of automatically and manually recorded behavioural variables summarised using multivariate analyses. The resulting personality descriptors and questing tick variables were used as explanatory variables in negative binomial generalised linear models of tick burden and Bayesian simulations were performed to better estimate coefficients. Tick burden was associated to body mass and sex, but not to personality descriptors, which was mainly associated to activity/exploration. These results are discussed regarding the complex relationships among individual personality, physiological status, space use and health status.


Assuntos
Ixodes , Infestações por Carrapato , Animais , Arvicolinae/parasitologia , Teorema de Bayes , Feminino , Ixodes/fisiologia , Masculino , Personalidade , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Infestações por Carrapato/veterinária
13.
Mikrochim Acta ; 189(9): 324, 2022 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-35939150

RESUMO

An electromembrane microextraction (EME)-assisted fluorescent molecularly imprinted polymer (MIP) sensing method is presented for detecting the total cathinone drugs in urine samples. In this detection system, the clean-up ability of EME eliminated the matrix effects on both target binding with MIPs and the luminescence of the fluorophore in the sensor. Moreover, by optimizing the extraction conditions of EME, different cathinone drugs with a same concentration show a same response on the single aggregation induced emission (AIE) based MIP (AIE-MIP) sensor (λex = 360 nm, λem = 467 nm). The recoveries were 57.9% for cathinone (CAT) and 78.2% for methcathinone (MCAT). The EME-assisted "light-up" AIE-MIP sensing method displayed excellent performance with a linear range of 2.0-12.0 µmol L-1 and a linear determination coefficient (R2) of 0.99. The limit of detection (LOD) value for EME-assisted "light-up" AIE-MIP sensing method was 0.3 µmol L-1. The relative standard deviation (RSD) values for the detection were found to be within the range 2.0-12.0%. To the best of our knowledge, this is the first time that determination of total illicit drugs with a single fluorescent MIP sensor was achieved and also the first utilization of sample preparation to tune the sensing signal of the sensor to be reported. We believe that this versatile combination of fluorescent MIP sensor and sample preparation can be used as a common protocol for sensing the total amount of a group of analytes in various fields.


Assuntos
Alcaloides , Impressão Molecular , Corantes , Limite de Detecção , Impressão Molecular/métodos , Polímeros
14.
Food Chem ; 397: 133567, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35940090

RESUMO

To understand the functionality of wheat flour starch lipids (SLs), non-starch lipids (NSLs), glycolipids (GLs), phospholipids (PLs), and neutral lipids (NLs) in non-leavened wheat-based products, their independent influence on noodle dough viscoelasticity and noodle texture were compared and the underlying mechanism was elucidated. Defatting caused slightly improved hydration, marginally promoting dough viscoelasticity and noodle springiness and adhesiveness but the resulting absence of starch-lipid complexes and few B-starch granules signally reduced the noodle hardness. Independently adding 2.50 g of these five lipids back into 100 g of defatted flour, GLs showed the most improved effects, followed by PLs, SLs, NSLs, and NLs. These lipids associated with gluten proteins and enhanced water-solids interplay, resulting in a significantly decreased SDS-soluble gluten proteins and further producing dough with increased ß-turn, moderate protein aggregation, and properly intensive microstructures. Consequently, the resultant noodle dough exhibited an optimal viscoelasticity and the cooked noodle had a desirable texture.

15.
ChemistrySelect ; 7(28): e202201229, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35942361

RESUMO

Herein, we report two novel multidentate luminogen proligands bis(3,5-diiodosalicylidene) carbohydrazone (H4L1) and bis(3,5-diiodosalicylidene) thiocarbohydrazone (H4L2), which are suitable candidates for biomedical applications. Though the thiocarbohydrazone H4L2 shows aggregation caused quenching (ACQ), the carbohydrazone H4L1 exhibits stronger fluorescence due to aggregation induced emission enhancement (AIEE). Molecular docking studies of H4L1 and H4L2 along with four similar (thio)carbohydrazones with the active sites of SARS-CoV-2 main protease 3CLpro reveals that the thiocarbohydrazones, in general, are showing better propensity compared to their oxygen analogues. Both the thiocarbohydrazones and the carbohydrazones, however, exhibit better binding potential at the active sites than that of some of the repurposed drugs such as chloroquine, hydroxychloroquine, lopinavir, ritonavir, darunavir and remdesivir. Also, the carbohydrazone H4L1 can be a better bioprobe compared to H4L2 as the former is found to have better binding potential with SARS-CoV-2 spike glycoprotein along with AIEE feature.

16.
Pharm Res ; 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945303

RESUMO

In this paper, we focus on providing a discrete formulation for a reduced aggregation population balance equation. The new formulation is simpler, easier to code, and adaptable to any type of grid. The presented method is extended to address a mixed-suspension mixed-product removal (MSMPR) system where aggregation and nucleation are the primary mechanisms that affect particle characteristics (or distributions). The performance of the proposed formulation is checked and verified against the cell average technique using both gelling and non gelling kernels. The testing is carried out on two benchmarking applications, namely batch and MSMPR systems. The new technique is shown to be computationally less expensive (approximately 40%) and predict numerical results with higher precision even on a coarser grid. Even with a revised grid, the new approach tends to outperform the cell average technique while requiring less computational effort. Thus the new approach can be easily adapted to model the crystallization process arising in pharmaceutical sciences and chemical engineering.

17.
J Food Biochem ; : e14369, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945661

RESUMO

Purified soya bean proteins (glycinin and conglycinin) are known to form amyloid-like aggregates in vitro at a higher temperature. Soya beans (chunks) are textured proteinaceous vegetables made from defatted soya flour by heating it above 100°C and extruding under high pressure. Therefore, it was assumed that subjecting the soya bean proteins to high temperatures raises the possibility of forming amyloids or amyloid-like protein aggregates. Hence, the present study aimed to examine the presence of amyloid-like protein aggregates in soya beans. The isolated protein aggregates from hydrated soya beans displayed typical characteristics of amyloids, such as the red shift in the absorption maximum (λmax ) of Congo red (CR), high Thioflavin T (ThT), and 8-Anilinonapthalene-1-sulfonate (ANS) binding, and fibrilar morphology. Furthermore, these aggregates were found to be stable against proteolytic hydrolysis, confirming the specific property of amyloids. The presence of amyloid-like structures in soya beans raises concerns about their implications for human nutrition and health. PRACTICAL APPLICATIONS: Protein aggregation has usually been considered detrimental. The traditional food-processing conditions, such as thermal processing, are associated with protein denaturation and aggregation. The formation of ordered protein aggregates with extensive ß-sheet are progressively evident in various protein-rich foods known as amyloid, which expands food safety concerns. Instead, it is also associated with poor nutritional characteristics. The present study concerns the presence of amyloid-like protein aggregates in widely consumed native soya beans, which are manufactured by extensive heat treatment of defatted soy flour. Although there is no indication of their toxicity, these aggregates are found to be proteolytically resistant. The seminal findings in this manuscript suggest that it is time to adapt innovative food processing and supplementation of bioactive molecules that can prevent the formation of such protein aggregates and help maximize the utilization of protein-based nutritional values.

18.
Chembiochem ; 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945807

RESUMO

The design of novel AIEGens, has generally been facilitated by disrupting the possibility of π-π stacking. The recent literature describes a novel strategy to design AIEGens by introducing anion-π + interactions to prevent the detrimental π-π stacking. This new strategy provides access to intrinsically charged AIEgens whose photophysical properties can be tuned either by incorporating different substituents on the π-molecular scaffold to modulate the acidity for tuning the interaction energy between a π-acceptor and counter-anions. This concept article provides a brief overview of the field, focusing on the synthesis of AIEGens, their photophysical properties, crystallography studies and their applications in live cell fluorescence imaging.

19.
Eng Appl Artif Intell ; 114: 105110, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35945944

RESUMO

In this work we are presenting an approach for fuzzy aggregation in ensembles of neural networks for forecasting. The aggregator is used in an ensemble to combine the outputs of the networks forming the ensemble. This is done in such a way that the total output of the ensemble is better than the outputs of the individual modules. In our approach a fuzzy system is used to estimate the weights that will be assigned to the outputs in the process of combining them in a weighted average calculation. The uncertainty in the process of aggregation is modeled with interval type-3 fuzzy, which in theory can outperform type-2 and type-1. Publicly available data sets of COVID-19 cases for several countries in the world were utilized to test the proposed approach. Simulation results of the COVID-19 data show the potential of the approach to outperform other aggregators in the literature.

20.
Open Biol ; 12(8): 220098, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35946309

RESUMO

Neurodegenerative diseases (NDs) are a diverse group of disorders characterized by the progressive degeneration of the structure and function of the central or peripheral nervous systems. One of the major features of NDs, such as Alzheimer's disease (AD), Parkinson's disease (PD) and Huntington's disease (HD), is the aggregation of specific misfolded proteins, which induces cellular dysfunction, neuronal death, loss of synaptic connections and eventually brain damage. By far, a great amount of evidence has suggested that TRIM family proteins play crucial roles in the turnover of normal regulatory and misfolded proteins. To maintain cellular protein quality control, cells rely on two major classes of proteostasis: molecular chaperones and the degradative systems, the latter includes the ubiquitin-proteasome system (UPS) and autophagy; and their dysfunction has been established to result in various physiological disorders including NDs. Emerging evidence has shown that TRIM proteins are key players in facilitating the clearance of misfolded protein aggregates associated with neurodegenerative disorders. Understanding the different pathways these TRIM proteins employ during episodes of neurodegenerative disorder represents a promising therapeutic target. In this review, we elucidated and summarized the diverse roles with underlying mechanisms of members of the TRIM family proteins in NDs.

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