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1.
Pest Manag Sci ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801197

RESUMO

BACKGROUND: Chrysodeixis includens (Walker) and Rachiplusia nu (Guenée) are major Plusiinae pests of soybean in the Southern Cone region of South America. In recent decades, C. includens was the main defoliator of soybean in Brazil, but from 2021 onwards, R. nu emerged as an important soybean pest in various regions of the country. Here, we characterize the differential susceptibility and resistance to insecticides in these Plusiinae pests from two soybean regions of Brazil. RESULTS: Except for spinetoram and chlorfenapyr (comparable lethality against both species) and a Bt-based biopesticide (more lethal for C. includens), the tested insecticides showed higher lethality against R. nu than against C. includens, but populations of the same species, even separated by long distances, presented similar resistance levels. For both species, the 90% lethal concentration (LC90) values of most insecticides were higher than the field-recommended dose. Nevertheless, the field-recommended doses of spinetoram, metaflumizone, emamectin benzoate, cyclaniliprole and chlorfenapyr showed comparable control efficacy against both species, whereas indoxacarb, chlorantraniliprole, flubendiamide, teflubenzuron and chlorfluazuron were more lethal for R. nu, and methoxyfenozide and the Bt-based insecticide were more lethal for C. includens. Thiodicarb, methomyl and lambda-cyhalothrin showed low lethality against both species. CONCLUSIONS: Large interspecific differences in the susceptibility to insecticides was found in major Plusiinae pests of soybean in Brazil. Furthermore, variations in susceptibility to insecticides occurred consistently among species and populations, regardless of the collection site and thus despite unequal temporal and spatial exposure to insecticides. These results demonstrate that accurate species identification is essential for effective control of Plusiinae in soybean. © 2024 Society of Chemical Industry.

2.
Biotechnol J ; 19(3): e2300307, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38472101

RESUMO

BACKGROUND: The worldwide growing demand for human insulin for treating diabetes could be supplied by transgenic animals producing insulin in their milk. METHODS AND RESULTS: Pseudo-lentivirus containing the bovine ß-casein promoter and human insulin sequences was used to produce modified adult fibroblasts, and the cells were used for nuclear transfer. Transgenic embryos were transferred to recipient cows, and one pregnancy was produced. Recombinant protein in milk was evaluated using western blotting and mass spectrometry. One transgenic cow was generated, and in milk analysis, two bands were observed in western blotting with a molecular mass corresponding to the proinsulin and insulin. The mass spectrometry analysis showed the presence of human insulin more than proinsulin in the milk, and it identified proteases in the transgenic milk that could convert proinsulin into insulin and insulin-degrading enzyme that could degrade the recombinant protein. CONCLUSION: The methodologies used for generating the transgenic cow allowed the detection of the production of recombinant protein in the milk at low relative expression compared to milk proteins, using mass spectrometry, which was efficient for detecting recombinant protein with low expression in milk. Milk proteases could act on protein processing converting recombinant protein to functional protein. On the other hand, some milk proteases could act in degrading the recombinant protein.


Assuntos
Leite , Proinsulina , Feminino , Gravidez , Animais , Bovinos , Humanos , Animais Geneticamente Modificados/metabolismo , Proinsulina/análise , Proinsulina/metabolismo , Leite/química , Proteínas Recombinantes/metabolismo , Insulina/análise , Peptídeo Hidrolases/metabolismo
3.
Trop Anim Health Prod ; 56(2): 92, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430430

RESUMO

This study aimed to identify and characterize runs of homozygosis (ROHs), genes involved in production characteristics and adaptation to tropical systems and to estimate the inbreeding coefficient of Curraleiro Pé-Duro (CPD) and Pantaneiro (PANT), two brazilian locally adapted cattle breeds. The results demonstrated that 79.25% and 54.29% of ROH segments were bigger than 8 Mb in CPD and PANT, respectively, indicating recent inbred matings in the studied population. Six homozygosis islands were identified simultaneously in both breeds, where 175 QTLs and 1072 genes previously described as associated with production traits are located. The inbreeding coefficient (FROH) estimated based on ROHs (FROH) showed that inbreeding is low (2 to 4%), which is different from expected for small populations such as locally adapted ones.


Assuntos
Endogamia , Polimorfismo de Nucleotídeo Único , Bovinos/genética , Animais , Homozigoto , Fenótipo , Reprodução
4.
Polymers (Basel) ; 15(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37836059

RESUMO

Thermoplastic polyurethanes (TPUs) are remarkably versatile polymers due to the wide range of raw materials available for their synthesis, resulting in physicochemical characteristics that can be tailored according to the specific requirements of their final applications. In this study, a renewable bio-based polyol obtained from soybean oil is used for the synthesis of TPU via reactive extrusion, and the influence of the bio-based polyol on the multi-phase structure and properties of the TPU is studied. As raw materials, 4,4'-diphenylmethane (MDI), 1,4-butanediol, a fossil-based polyester polyol, and a bio-based polyol are used. The fossil-based to soybean-based polyol ratios studied are 100/0, 99/1, 95/5, 90/10, 80/20, and 50/50% by weight, respectively. The TPUs were characterized by size exclusion chromatography (SEC), gel content analysis, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS), dynamic mechanical analysis (DMA), and contact angle measurements. The results reveal that incorporating the renewable polyol enhances the compatibility between the rigid and flexible segments of the TPU. However, due to its high functionality, the addition of soybean-based polyol can promote cross-linking. This phenomenon reduces the density of hydrogen bonds within the material, also reducing polarity and restricting macromolecular mobility, as corroborated by higher glass transition temperature (Tg) values. Remarkably, the addition of small amounts of the bio-based polyol (up to 5 wt.% of the total polyol content) results in high-molecular-weight TPUs with lower polarity, combined with suitable processability and mechanical properties, thus broadening the range of applications and improving their sustainability.

5.
Polymers (Basel) ; 14(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35956679

RESUMO

Thermoplastic polyurethanes (TPUs) are versatile polymers presenting a broad range of properties as a result of their countless combination of raw materials­in essence, isocyanates, polyols, and chain extenders. This study highlights the effect of two different chain extenders and their combination on the structure−property relationships of TPUs synthesized by reactive extrusion. The TPUs were obtained from 4,4-diphenylmethane diisocyanate (MDI), polyester diols, and the chain extenders 1,4-butanediol (BDO) and dipropylene glycol (DPG). The BDO/DPG ratios studied were 100/0, 75/25, 50/50, 25/75, and 0/100 wt.%. The TPUs were characterized by size exclusion chromatography (SEC), Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS), UV−vis spectroscopy, and physical-mechanical properties. The results indicate that DPG promotes compatibility between rigid (HS) and flexible (SS) segments of TPUs. Consequently, increasing DPG content (>75 wt.%) reduced the organization of the rigid segments and the degree of phase separation, increasing the polydispersity of the interdomain distance and the transparency in the UV−visible spectrum of the TPUs. Furthermore, increasing DPG content also reduced the amount of hydrogen bonds present in the rigid phase, reducing or extinguishing its glass transition temperature (TgHS) and melting temperature (Tm), and increasing the glass transition temperature of the flexible phase (TgSS). Therefore, increasing DPG content leads to a deterioration in mechanical properties and hydrolysis resistance.

6.
Ecol Evol ; 12(7): e9086, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35845383

RESUMO

In natural ecosystems, arthropod predation on herbivore prey is higher at lower latitudes, mirroring the latitudinal diversity gradient observed across many taxa. This pattern has not been systematically examined in human-dominated ecosystems, where frequent disturbances can shift the identity and abundance of local predators, altering predation rates from those observed in natural ecosystems. We investigated how latitude, biogeographical, and local ecological factors influenced arthropod predation in Brassica oleracea-dominated agroecosystems in 55 plots spread among 5 sites in the United States and 4 sites in Brazil, spanning at least 15° latitude in each country. In both the United States and Brazil, arthropod predator attacks on sentinel model caterpillar prey were highest at the highest latitude studied and declined at lower latitudes. The rate of increased arthropod attacks per degree latitude was higher in the United States and the overall gradient was shifted poleward as compared to Brazil. PiecewiseSEM analysis revealed that aridity mediates the effect of latitude on arthropod predation and largely explains the differences in the intensity of the latitudinal gradient between study countries. Neither predator richness, predator density, nor predator resource availability predicted variation in predator attack rates. Only greater non-crop plant density drove greater predation rates, though this effect was weaker than the effect of aridity. We conclude that climatic factors rather than ecological community structure shape latitudinal arthropod predation patterns and that high levels of aridity in agroecosystems may dampen the ability of arthropod predators to provide herbivore control services as compared to natural ecosystems.

7.
Mol Reprod Dev ; 89(9): 375-398, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35802460

RESUMO

Besides their canonical roles as energy sources, short-chain fatty acids act as metabolic regulators of gene expression through histone posttranslational modifications. Ketone body ß-hydroxybutyrate (BHB) causes a novel epigenetic modification, histone lysine ß-hydroxybutyrylation (Kbhb), which is associated with genes upregulated in starvation-responsive metabolic pathways. Dairy cows increase BHB in early lactation, and the effects of this increase on cellular epigenomes are unknown. We searched for and identified that Kbhb is present in bovine tissues in vivo and confirmed that this epigenetic mark is responsive to BHB in bovine and human fibroblasts cultured in vitro in a dose-dependent manner. Maturation of cumulus-oocyte complexes with high concentrations of BHB did not affect the competence to complete meiotic maturation or to develop until the blastocyst stage. BHB treatment strongly induced H3K9bhb in cumulus cells, but faintly in oocytes. RNA-seq analysis in cumulus cells indicated that BHB treatment altered the expression of 345 genes. The downregulated genes were mainly involved in glycolysis and ribosome assembly pathways, while the upregulated genes were involved in mitochondrial metabolism and oocyte development. The genes and pathways altered by BHB will provide entry points to carry out functional experiments aiming to mitigate metabolic disorders and improve fertility in cattle.


Assuntos
Ácido 3-Hidroxibutírico , Células do Cúmulo , Epigênese Genética , Histonas , Lisina , Oócitos , Ácido 3-Hidroxibutírico/metabolismo , Ácido 3-Hidroxibutírico/farmacologia , Animais , Bovinos , Células do Cúmulo/metabolismo , Feminino , Histonas/metabolismo , Humanos , Lisina/metabolismo , Oócitos/metabolismo
8.
J Surg Oncol ; 126(1): 20-27, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35689578

RESUMO

BACKGROUND: Risk-reducing operations are an important part of the management of hereditary predisposition to cancer. In selected cases, they can considerably reduce the morbidity and mortality associated with cancer in this population. OBJECTIVES: The Brazilian Society of Surgical Oncology (BSSO) developed this guideline to establish national benchmarks for cancer risk-reducing operations. METHODS: The guideline was prepared from May to December 2021 by a multidisciplinary team of experts to discuss the surgical management of cancer predisposition syndromes. Eleven questions were defined and assigned to expert groups that reviewed the literature and drafted preliminary recommendations. Following a review by the coordinators and a second review by all participants, the groups made final adjustments, classified the level of evidence, and voted on the recommendations. RESULTS: For all questions including risk-reducing colectomy, gastrectomy, and thyroidectomy, a major agreement was achieved by the participants, always using accessible alternatives. CONCLUSION: This and its accompanying article represent the first guideline in cancer risk reduction surgery developed by the BSSO and it should serve as an important reference for the management of families with cancer predisposition.


Assuntos
Neoplasias , Oncologia Cirúrgica , Brasil/epidemiologia , Humanos , Glândula Tireoide
9.
J Econ Entomol ; 115(2): 631-636, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35244181

RESUMO

This study evaluated intra- and interspecific variation regarding the susceptibility to insecticides of key pentatomid pests of soybean (Glycine max L.) and maize (Zea mays L.) crops in Brazil. To perform bioassays, populations of Euschistus heros (F.), Diceraeus (=Dichelops) furcatus (F.), Nezara viridula (L.), and Piezodorus guildinii (Westwood) (Hemiptera: Pentatomidae) were collected in soybean fields in Southern Brazil during the 2020/2021 crop season. Then, stink bugs were exposed to doses of commercial insecticides commonly applied for its control in dip-test bioassays using fresh green bean pods. In general, all stink bug species and populations studied were susceptible to acephate, acetamiprid + bifenthrin, imidacloprid + bifenthrin, and ethiprole, with mortality rates > 80%. Most populations of E. heros and D. furcatus, considered the main stink bugs that attack soybean and maize, respectively, presented low or intermediate susceptibility to acetamiprid + α-cypermethrin, ζ-cypermethrin + bifenthrin, dinotefuran + λ-cyhalothrin, and bifenthrin + carbosulfan. Except for bifenthrin + carbosulfan (mortality < 57%), secondary stink bugs species that attack soybean (N. viridula and P. guildinii) showed pronounced susceptibility to all insecticides tested, with mortality rates > 70%. In summary, the populations of E. heros and D. furcatus showed diminished susceptibility to various insecticides formulated with the mixture of neonicotinoids + pyrethroids, whereas N. viridula and P. guildinii were most susceptible to the insecticides evaluated. The implications of these findings to integrated and resistance management programs are discussed.


Assuntos
Heterópteros , Inseticidas , Animais , Brasil , Glycine max , Zea mays
10.
Mol Reprod Dev ; 88(9): 628-643, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34402123

RESUMO

In vivo- and in vitro-produced bovine embryos have different metabolic profiles and differences in gene transcription patterns. These embryos also have a distinct ability to establish and sustain early pregnancies. Small extracellular vesicles (sEVs) are secreted by embryos and carry bioactive molecules, such as miRNAs. We hypothesize that in vivo or in vitro-produced bovine hatched blastocysts on Day 9 and the sEVs secreted by them have different miRNA profiles. To address this hypothesis, embryos of both groups were placed in in vitro culture on Day 7. After 48 h, hatched embryos and hatched embryo-conditioned media (eCM) of both groups were collected. A total of 210 miRNAs were detected in embryos of both groups, of these 6 miRNAs were downregulated, while 7 miRNAs were upregulated in vitro group when compared to in vivo group. sEVs were isolated from eCM to determine miRNA profile. A total of 106 miRNAs were detected in both groups, including 14 miRNAs upregulated in sEVs from in vivo-eCM, and 2 miRNAs upregulated in sEVs from in vitro-eCM. These miRNAs express in embryos and sEVs secreted by them regulate early embryonic developmental and endometrial pathways, which can modify embryo-maternal communication during early pregnancy and consequently affect pregnancy establishment.


Assuntos
Vesículas Extracelulares , MicroRNAs , Animais , Blastocisto/metabolismo , Bovinos , Técnicas de Cultura Embrionária , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/genética , Vesículas Extracelulares/metabolismo , Feminino , MicroRNAs/genética , MicroRNAs/metabolismo , Gravidez
11.
Pest Manag Sci ; 77(12): 5367-5374, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34310024

RESUMO

BACKGROUND: Fall armyworm (FAW), Spodoptera frugiperda (Smith), is an economically important pest worldwide. In this study, we selected a genotype of FAW resistant to chlorpyrifos from a field-collected population, characterized the genetic basis of resistance, and evaluated cross-resistance and mechanisms of resistance using synergists. RESULTS: The LD50 values of chlorpyrifos for the resistant (Clorp-R) and susceptible (Sus) FAW genotypes were 24.26 and 0.023 µg per larva, respectively, representing a resistance ratio > 1050-fold. The LD50 values of chlorpyrifos against heterozygotes were 3.34 and 4.00 µg per larva, suggesting that resistance is autosomally inherited. The chlorpyrifos resistance in FAW was influenced by few genes, with the minimum numbers of segregations being 1.74 and 1.88. On chlorpyrifos-sprayed plants and leaves, Clorp-R and heterozygote genotypes showed >95% and >52% survival, respectively, whereas the Sus genotype had no survival, indicating that the resistance is incompletely dominant at the field rate of chlorpyrifos. The Clorp-R genotype presented some cross-resistance to acephate, but low cross-resistance to thiodicarb, methomyl, chlorfenapyr, flubendiamide, methoxyfenozide, spinetoram, and teflubenzuron. The synergists piperonyl butoxide, diethyl maleate, and S,S,S-tributyl phosphorotrithiotate did not have relevant effects on the Clorp-R genotype, suggesting a minor role for metabolic resistance. CONCLUSIONS: The inheritance of chlorpyrifos resistance in FAW was characterized as autosomal, incompletely dominant, and polygenic, with metabolic resistance playing a small role in the detoxification of chlorpyrifos. Low cross-resistance between chlorpyrifos and other mode of action (MoA) insecticides occurs in FAW, highlighting the importance of considering the rotation of MoA as a strategy to delay resistance. © 2021 Society of Chemical Industry.


Assuntos
Clorpirifos , Inseticidas , Mariposas , Animais , Clorpirifos/farmacologia , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Larva/genética , Spodoptera/genética
12.
Environ Entomol ; 50(4): 898-908, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34018549

RESUMO

Spodoptera frugiperda (J. E. Smith, 1797) is a polyphagous pest of global relevance due to the damage it inflicts on agricultural crops. In South American countries, this species is one of the principal pests of maize and cotton. Currently, S. frugiperda is also emerging as an important pest of soybeans and winter cereals in Brazil. Chemical control is one of the main control tactics against S. frugiperda, even though resistance against numerous modes of action insecticides has been reported. To support insect resistance management programs, we evaluated the fitness costs of resistance of S. frugiperda to the acetylcholinesterase inhibitor chlorpyrifos. Fitness costs were quantified by comparing biological parameters of chlorpyrifos-resistant and -susceptible S. frugiperda and their F1 hybrids (heterozygotes) on non-Bt cotton, non-Bt maize, non-Bt soybean, and oats. The results revealed that the chlorpyrifos-resistant genotype showed lower pupa-to-adult and egg-to-adult survivorship and reduced larval weights on oats; longer neonate-to-pupa and egg-to-adult developmental periods, and lower pupal weights and fecundity on maize; lower pupal weights on soybean; and reduced fecundity on cotton compared with the chlorpyrifos-susceptible genotype. Fitness costs also affected fertility life table parameters of the resistant genotype, increasing the mean length of a generation on cotton and maize and reducing the potential for population growth on all hosts. These findings suggest fitness costs at the individual and population levels of chlorpyrifos resistance in S. frugiperda, indicating that removal of the selective agent from the environment would result in reduced resistance and opportunities for the restoration of susceptibility.


Assuntos
Clorpirifos , Proteínas Hemolisinas , Animais , Proteínas de Bactérias/genética , Brasil , Endotoxinas , Proteínas Hemolisinas/genética , Resistência a Inseticidas/genética , Plantas Geneticamente Modificadas , Spodoptera/genética , Zea mays/genética
13.
An Acad Bras Cienc ; 93(2): e20200799, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33950143

RESUMO

Epoxy systems are widely applied as adhesives in the aerospace industry. They have excellent adhesion properties, however, being thermosetting, epoxy systems show fracture brittleness characteristics. Polysulfide and polymercaptans are good options to increase the flexibility of the epoxy adhesive. Thermal analysis techniques are generally used to evaluate the curing degree of epoxy systems. In most cases, when infrared (IR) analysis is used, it is employed qualitatively. This paper presents the reaction study of a DGEBA epoxy prepolymer with diethylenetriamine (DETA) and linear and branched dodecyl mercaptans as flexibilizers. Conversion data and curing time were assessed qualitatively and quantitatively by Fourier Transform Infrared Spectroscopy (FT-IR) in the medium infrared region (MIR) and in the near infrared region, using near infrared reflectance accessory (NIRA). NIRA methodology showed satisfactory results, with errors between 3 and 7%, especially in samples with lower amine contents. Mechanical tests confirmed the flexibilization of the cured epoxy system by the addition of mercaptans, indicating a lower crosslinking degree in the matrix. Young's modulus (E) significantly decreased from 2017 MPa to 578 MPa with the addition of approximately 20 wt% of normal dodecyl mercaptan to the epoxy system.


Assuntos
Resinas Epóxi , Compostos de Sulfidrila , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Arq. bras. med. vet. zootec. (Online) ; 73(2): 517-521, Mar.-Apr. 2021. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1248950

RESUMO

A análise dos padrões morfológicos e morfométricos das microestruturas capilares é uma técnica não invasiva que pode ser utilizada para identificar espécies de mamíferos. Esta técnica pode ser aplicada em diversas áreas da ciência animal, tais como controle de qualidade de alimentos e análises forenses. Dada a dificuldade de obter seções transversais de pelos de guarda para expor o córtex, a maioria dos estudos analisou apenas os componentes medulares e cuticulares do pelo. A inclusão do córtex capilar de guarda em uma análise tricológica pode proporcionar uma descrição mais precisa das raças ou espécies de mamíferos. O presente estudo propõe um novo método para a execução de cortes transversais que expõem o córtex do pelo guarda de mamíferos utilizando um criostato.(AU)


Assuntos
Animais , Ciências Forenses/tendências , Pelo Animal/ultraestrutura , Análise do Cabelo/veterinária , Microscopia/métodos
15.
Mol Biol Rep ; 48(2): 1985-1994, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33619662

RESUMO

Reck (REversion-inducing Cysteine-rich protein with Kazal motifs) tumor suppressor gene encodes a multifunctional glycoprotein which inhibits the activity of several matrix metalloproteinases (MMPs), and has the ability to modulate the Notch and canonical Wnt pathways. Reck-deficient neuro-progenitor cells undergo precocious differentiation; however, modulation of Reck expression during progression of the neuronal differentiation process is yet to be characterized. In the present study, we demonstrate that Reck expression levels are increased during in vitro neuronal differentiation of PC12 pheochromocytoma cells and P19 murine teratocarcinoma cells and characterize mouse Reck promoter activity during this process. Increased Reck promoter activity was found upon induction of differentiation in PC12 cells, in accordance with its increased mRNA expression levels in mouse in vitro models. Interestingly, Reck overexpression, prior to the beginning of the differentiation protocol, led to diminished efficiency of the neuronal differentiation process. Taken together, our findings suggest that increased Reck expression at early stages of differentiation diminishes the number of neuron-like cells, which are positive for the beta-3 tubulin marker. Our data highlight the importance of Reck expression evaluation to optimize in vitro neuronal differentiation protocols.


Assuntos
Proteínas Ligadas por GPI/metabolismo , Genes Supressores de Tumor , Neurogênese/genética , Teratocarcinoma/metabolismo , Animais , Sítios de Ligação , Citometria de Fluxo , Proteínas Ligadas por GPI/genética , Regulação Neoplásica da Expressão Gênica/genética , Camundongos , Células PC12 , Regiões Promotoras Genéticas , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Teratocarcinoma/genética , Tubulina (Proteína)/metabolismo , Regulação para Cima
16.
Transl Anim Sci ; 4(1): 84-94, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32704969

RESUMO

In Exp. 1, Brachiaria ruziziensis (11.1 % CP) was inoculated or not with two sources of monensin, resulting in three treatments: 1) no monensin inoculation (CONT), 2) 20 mg of monensin sodium-A/kg of DM (Elanco Animal Health; MON-A), and 3) 20 mg of monensin sodium-B/kg of DM (Shandong Qilu King-Phar Pharmaceutical Co. Ltd.; MON-B). Three rumen-fistulated Jersey steers were offered a cool-season forage-based diet and were used as the rumen inoculum donors. Volatile fatty acids concentrations were evaluated at 0, 6, 12, 24, 30, and 48 h after treatment inoculation. Overall, acetate and butyrate concentrations were reduced in MON-A vs. CONT (P ≤ 0.02), whereas both monensin products reduced Ac:Pr ratio vs. CONT (P ≤ 0.01); however, MON-A also (P = 0.05) reduced the Ac:Pr ratio vs. MON-B. A treatment × hour interaction was detected for rumen propionate concentration (P = 0.01), primarily because MON-A resulted in greater propionate than CONT and MON-B at 24 and 48 h (P ≤ 0.03), but no differences were observed between CONT vs. MON-B (P ≥ 0.27). In Exp. 2, 240 Nellore bulls (initial BW = 363.2 ± 40.9 kg) were ranked and blocked according to initial BW, and within blocks animals were allotted into pens (n = 10 pens/treatment). Pens were randomly assigned into one of three treatments: 1) corn-based diet with no monensin (CONT), 2) CONT plus 28 mg of MON-A/kg of DM, and 3) CONT plus 28 mg of MON-B/kg of DM. The CONT diet was composed of sugarcane bagasse, ground corn, DDGS, urea, and a mineral-vitamin mix. The experimental period lasted 106 d and was divided into a 21-d adaptation period and an 85-d finishing phase. During the adaptation phase, both monensin sources increased (P ≤ 0.01) BW change, ADG, and F:G, as well as reduced DMI variation (P = 0.02). When the entire experimental period was evaluated, no treatment effects were detected for final BW, DMI, and ADG (P ≥ 0.26). Nonetheless, DMI variation was reduced as monensin was included (P = 0.01) and only MON-A improved the efficiency by reducing F:G vs. CONT (P = 0.05) and biological efficiency vs. MON-B (P = 0.05). Additionally, carcass ADG tended (P = 0.10) to be greater for MON-A vs. MON-B, whereas no other differences in the carcass characteristics were observed (P ≥ 0.53). In summary, the source of monensin inoculated in vitro and offered to Nellore bulls during the feedlot phase significantly affected the energetic efficiency and the performance of the animals.

17.
J Invasive Cardiol ; 32(9): 335-341, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32568096

RESUMO

OBJECTIVES: We sought to assess the effects of a high loading dose of rosuvastatin (40 mg) on acute inflammatory response after coronary stenting. METHODS: Patients with stable coronary disease without statin use (≥7 days) and undergoing elective percutaneous coronary intervention (PCI) in a native coronary artery were randomized to receive a loading dose of rosuvastatin (n = 64) or not (n = 61). Blood samples were obtained before statin intake (time point A), 3 hours after medication (time point B), and 3 hours after PCI (time point C). The primary goal was the comparison in the variation of the serum inflammatory markers and their gene expression at the different time points between the two groups. RESULTS: Baseline clinical, angiographic, and procedural characteristics did not significantly differ between the groups, except for the more frequent use of postdilation in the control group (73.4% vs 90.2%; P=.02). Patients pretreated with statin showed a reduction in the serum levels of interleukin (IL)-1ß (Δ = -0.491 pg/mL; Pinteraction<.001), IL-6 (Δ = -0.209 pg/mL; Pinteraction<.001), and plasminogen activator inhibitor 1 (Δ = -1.573 pg/mL; Pinteraction<.001) as well as in their genetic expression, which was not observed in the control group. Regarding high-sensitivity c-reactive protein, there was no significant variation in its value from time point A to C in patients pretreated with statin (P=.58) while it significantly increased in the control group (P=.04). CONCLUSIONS: Among patients with stable coronary artery disease undergoing PCI with stents, pretreatment with high dose of rosuvastatin resulted in significant reduction in the serum levels of important inflammatory markers and their genetic expression.


Assuntos
Síndrome Coronariana Aguda , Doença da Artéria Coronariana , Inibidores de Hidroximetilglutaril-CoA Redutases , Inflamação , Intervenção Coronária Percutânea , Rosuvastatina Cálcica/administração & dosagem , Proteína C-Reativa/análise , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/cirurgia , Humanos , Inflamação/sangue , Interleucina-1beta/sangue , Intervenção Coronária Percutânea/efeitos adversos , Inibidor 1 de Ativador de Plasminogênio/sangue
18.
J Phys Condens Matter ; 32(7): 075602, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-31671418

RESUMO

We develop a comparative study of the extended Hubbard model on three-site clusters of triangular and linear geometries, searching for geometrical-frustration effects on thermodynamic properties. Using exact diagonalization, we evaluate physical quantities such as specific heat, entropy, and spin correlations as functions of temperature, varying interaction parameters and electron density. In particular, we highlight the existence of clear signatures of frustration in the thermal behavior of the electronic specific heat in triangular clusters, which allows us to suggest that specific-heat measurements may be an important experimental tool to detect geometrical frustration in correlated-electron systems.

19.
Anal Sci ; 35(11): 1255-1261, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31378775

RESUMO

This paper discusses about the improvement of electrochemical characteristics of graphite paste electrode chemically modified with chitosan through physical crosslinking of the biopolymer with sodium tripolyphosphate. Biopolymer characterizations were performed by scanning electron microscopy, Fourier transform infrared spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. The electrochemical characterization of Pb with graphite paste electrode modified with chitosan crosslinked with sodium tripolyphosphate (GPE-CTS-TPP) showed that the process is quasireversible, controlled by adsorption and involves the transfer of two electrons. Additionally, the physical crosslinking process decreased the electrode resistance as well as improved the electron transfer rate. Once the GPE-CTS-TPP showed enhanced morphological and electrochemical characteristics, it was applied for Pb determination by square wave anodic stripping voltammetry. The method presented appropriate accuracy (recoveries from 95 to 108% and concordance with comparative method between 90 and 107%), high sensitivity (limit of detection and quantification of Pb were 0.73 and 2.44 µg L-1, respectively) and could be applied to analytical determinations.


Assuntos
Quitosana/análogos & derivados , Eletroquímica/instrumentação , Chumbo/análise , Adsorção , Quitosana/química , Eletrodos , Grafite/química , Chumbo/química , Limite de Detecção
20.
Catheter. cardiovasc. interv ; 92(6): 368-e374, Nov. 2018. tab, graf, ilus
Artigo em Inglês | Sec. Est. Saúde SP, CONASS, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1223203

RESUMO

INTRODUCTION: Bioresorbable coronary scaffolds (BRS) have been developed to increase the late safety of coronary angioplasty by providing transitory coronary support and then being fully incorporated to the vessel wall. In the present trial, we sought to evaluate the performance and changes over time in the DESolveTM novolimus-eluting BRS using serial intravascular ultrasound (IVUS) in patients submitted to percutaneous coronary interventions. Methods: Single-center, prospective, non-randomized study involving 17 consecutive patients submitted to implantation of the DESolveTM scaffold and serial evaluated with IVUS at different time points (post procedure, 6 and 18 months). Primary endpoint included the variation in lumen, scaffold, and vessel diameter and area along the months. RESULTS: Angiographic success was achieved in all cases. Scaffold area and volume on IVUS were significantly greater at 6 months than at baseline (6.41 6 1.35 mm2 vs. 7.35 6 1.53 mm2, P < 0.002; and 101.19 6 20.9 mm3 vs. 118.51 6 26.6 mm 3, P 5 0.001). Late lumen loss was 0.22 6 0.30 mm at 6 months and 0.33 6 0.44 mm at 18 months. No major adverse cardiac events occurred. At late follow-up (18 months) the scaffold was not visualized by IVUS; therefore the evaluation was restricted to lumen and vessel at that time point. CONCLUSIONS: IVUS serial evaluation of the novel DESolve BRS showed an increase in the device dimensions between baseline and 6 months, with concomitant enlargement of lumen dimensions and effective suppression of neointimal proliferation. At 18 months, no footprint of the scaffold was detected and the initial lumen enlargement was sustained.


Assuntos
Angioplastia , Stents Farmacológicos , Intervenção Coronária Percutânea
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