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1.
Brain Topogr ; 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38753271

RESUMEN

White matter dissection (WMD) involves isolating bundles of myelinated axons in the brain and serves to gain insights into brain function and neural mechanisms underlying neurological disorders. While effective, cadaveric brain dissections pose certain challenges mainly due to availability of resources. Technological advancements, such as photogrammetry, have the potential to overcome these limitations by creating detailed three-dimensional (3D) models for immersive learning experiences in neuroanatomy. This study aimed to provide a detailed step-by-step WMD captured using two-dimensional (2D) images and 3D models (via photogrammetry) to serve as a comprehensive guide for studying white matter tracts of the brain. One formalin-fixed brain specimen was utilized to perform the WMD. The brain was divided in a sagittal plane and both cerebral hemispheres were stored in a freezer at -20 °C for 10 days, then thawed under running water at room temperature. Micro-instruments under an operating microscope were used to perform a systematic lateral-to-medial and medial-to-lateral dissection, while 2D images were captured and 3D models were created through photogrammetry during each stage of the dissection. Dissection was performed with comprehensive examination of the location, main landmarks, connections, and functions of the white matter tracts of the brain. Furthermore, high-quality 3D models of the dissections were created and housed on SketchFab®, allowing for accessible and free of charge viewing for educational and research purposes. Our comprehensive dissection and 3D models have the potential to increase understanding of the intricate white matter anatomy and could provide an accessible platform for the teaching of neuroanatomy.

2.
Transl Anim Sci ; 6(2): txac028, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35387309

RESUMEN

There has been an intense debate regarding the economic, social, and environmental sustainability of confinement versus grazing dairy systems. Our goal was to conduct a meta-analysis to compare dry matter intake, milk yield and composition, nutrient use efficiency (i.e., feed efficiency, milk N efficiency), and predicted enteric CH4 emissions using studies that simultaneously evaluated confinement and grazing. We were able to include in the meta-analysis 8 peer-reviewed articles that met the following selection criteria: (1) publication between 1991 and 2021 in English language, (2) report either SEM or SD, (3) inclusion of at least 1 confinement [total mixed ration or fresh cut herbage fed indoors (i.e., zero-grazing)] and 1 grazing treatment in the same study, and (4) use of markers (internal or external) to estimate herbage dry matter intake. Two unpublished experiments were added to the data set resulting in a total of 10 studies for comparing confinement and grazing. The magnitude of the effect (i.e., effect size) was evaluated using weighted raw mean differences between grazing and confinement systems for a random effect model. Enteric CH4 production was predicted as follows: CH4 (g/d) = 33.2 (13.54) + 13.6 (0.33) × dry matter intake + 2.43 (0.245) × neutral detergent fiber. Dry matter intake (-9.5%), milk yield (-9.3%), milk fat yield (-5.8%), milk protein yield (-10%), and energy-corrected milk (-12%) all decreased in grazing versus confined dairy cows. In contrast, concentration of milk fat and feed efficiency (energy-corrected milk/dry matter intake) were not affected by management system. Whereas milk protein concentration increased, milk nitrogen (N) efficiency (milk N/N intake) tended to decrease in grazing compared with confinement. Predicted enteric CH4 production was 6.1% lower in grazing than confined dairy cows. However, CH4 yield (g/kg of dry matter intake) and CH4 intensity (g/kg of energy-corrected milk) did not change between confinement and grazing. In conclusion, while production performance decreased in grazing dairy cows, nutrient use efficiency and predicted enteric CH4 emissions were relatively similar in both management systems. Results of our meta-analysis should be interpreted with caution due to the small number of studies that met our inclusion criteria leading to a limited number of treatment mean comparisons.

3.
J Dairy Sci ; 104(7): 7653-7670, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33814134

RESUMEN

A meta-analysis of 158 peer-reviewed articles was conducted to examine effects of inoculation with Lactobacillus buchneri (LB)-based inoculants (LBB) that did or did not include homolactic or obligate heterolactic bacteria on silage fermentation and aerobic stability. A complementary meta-analysis of 12 articles examined LBB inoculation effects on dairy cow performance. Raw mean differences between inoculant and control treatment means weighted by inverse variance were compared with a hierarchical effects model that included robust variance estimation. Meta-regression and subgrouping analysis were used to identify effects of covariates including forage type, application rate (≤104, 105, 106, or ≥ 107 cfu/g as fed), bacteria type (LB vs. LB plus other bacteria), enzyme inclusion, ensiling duration, and silo type (laboratory or farm scale). Inoculation with LBB increased acetate (62%), 1, 2 propanediol (364%) and propionate (30%) concentration and aerobic stability (73.8%) and reduced lactate concentration (7.2%), yeast counts (7-fold) and mold counts (3-fold). Feeding inoculated silage did not affect milk yield, dry matter intake, and feed efficiency in lactating dairy cows. However, forage type, inoculant composition, and dose effects on silage quality measures were evident. Inoculation with LBB increased aerobic stability of all silages except tropical grasses. Adding obligate homolactic or facultative heterolactic bacteria to LB prevented the small increase in DM losses caused by LB alone. The 105 and 106 cfu/g rates were most effective at minimizing DM losses while aerobic stability was only increased with 105, 106, and ≥ 107 cfu/g rates. Inoculation with LBB increased acetate concentration, reduced yeast counts and improved aerobic stability but did not improve dairy cow performance.


Asunto(s)
Lactancia , Ensilaje , Aerobiosis , Animales , Bovinos , Femenino , Fermentación , Lactobacillus , Ensilaje/análisis , Zea mays
4.
ACS Biomater Sci Eng ; 6(8): 4523-4538, 2020 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-33455175

RESUMEN

IR-780 iodide is a fluorescent dye with optical properties in the near-infrared region that has applications in tumor detection and photothermal/photodynamic therapy. This multifunctional effect led to the development of theranostic nanoparticles with both IR-780 and chemotherapeutic drugs such as docetaxel, doxorubicin, and lonidamine. In this work, we developed two albumin-based nanoparticles containing near-infrared IR-780 iodide multifunctional dyes, one of them possessing a magnetic core. Molecular docking with AutoDock Vina studies showed that IR-780 binds to bovine serum albumin (BSA) with greater stability at a higher temperature, allowing the protein binding pocket to better fit this dye. The theoretical analysis corroborates the experimental protocols, where an enhancement of IR-780 was found coupled to BSA at 60 °C, even 30 days after preparation, in comparison to 30 °C. In vitro assays monitoring the viability of Ehrlich ascites carcinoma cells revealed the importance of the inorganic magnetic core on the nanocarrier photothermal-cytotoxic effect. Fluorescence molecular tomography measurements of Ehrlich tumor-bearing Swiss mice revealed the biodistribution of the nanocarriers, with marked accumulation in the tumor tissue (≈3% ID). The histopathological analysis demonstrated strong increase in tumoral necrosis areas after 24 and 72 h after treatment, indicating tumor regression. Tumor regression analysis of nonirradiated animals indicate a IR-780 dose-dependent antitumoral effect with survival rates higher than 70% (animals monitored up to 600 days). Furthermore, an in vivo photothermal therapy procedure was performed and tumor regression was also verified. These results show a novel insight for the biomedical application of IR-780-albumin-based nanocarriers, namely cancer therapy, not only by photoinduced therapy but also by a nonirradiation mechanism. Safety studies (acute oral toxicity, cardiovascular evaluation, and histopathological analysis) suggest potential for clinical translation.


Asunto(s)
Hipertermia Inducida , Animales , Línea Celular Tumoral , Indoles , Ratones , Simulación del Acoplamiento Molecular , Fototerapia , Distribución Tisular
5.
PLoS One ; 14(9): e0223017, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31557229

RESUMEN

The West Nile Virus (WNV) NS2B-NS3 protease is an attractive target for the development of therapeutics against this arboviral pathogen. In the present investigation, the screening of a small library of fifty-eight synthetic compounds against the NS2-NB3 protease of WNV is described. The following groups of compounds were evaluated: 3-(2-aryl-2-oxoethyl)isobenzofuran-1(3H)-ones; eugenol derivatives bearing 1,2,3-triazolic functionalities; and indan-1,3-diones with 1,2,3-triazolic functionalities. The most promising of these was a eugenol derivative, namely 4-(3-(4-allyl-2-methoxyphenoxy)-propyl)-1-(2-bromobenzyl)-1H-1,2,3-triazole (35), which inhibited the protease with IC50 of 6.86 µmol L-1. Enzyme kinetic assays showed that this derivative of eugenol presents competitive inhibition behaviour. Molecular docking calculations predicted a recognition pattern involving the residues His51 and Ser135, which are members of the catalytic triad of the WNV NS2B-NS3 protease.


Asunto(s)
Antivirales/farmacología , Endopeptidasas/metabolismo , Inhibidores de Proteasas/farmacología , Proteínas no Estructurales Virales/antagonistas & inhibidores , Virus del Nilo Occidental/enzimología , Antivirales/química , Dominio Catalítico/efectos de los fármacos , Descubrimiento de Drogas , Endopeptidasas/química , Eugenol/química , Histidina/química , Histidina/metabolismo , Indanos/química , Concentración 50 Inhibidora , Simulación del Acoplamiento Molecular , Inhibidores de Proteasas/química , Serina/química , Serina/metabolismo , Relación Estructura-Actividad , Proteínas no Estructurales Virales/química
6.
Eur J Med Chem ; 149: 98-109, 2018 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-29499491

RESUMEN

A simple and efficient Knoevenagel procedure for the synthesis of 2-arylidene indan-1,3-diones is herein reported. These compounds were prepared via ZrOCl2·8H2O catalyzed reactions of indan-1,3-dione with several aromatic aldehydes and using water as the solvent. The 2-arylidene indan-1,3-diones were obtained with 53%-95% yield within 10-45 min. The synthesized compounds were evaluated as inhibitors of the NS2B-NS3 protease of West Nile Virus (WNV). It was found that hydroxylated derivatives impaired enzyme activity with varying degrees of effectiveness. The most active hydroxylated derivatives, namely 2-(4-hydroxybenzylidene)-1H-indene-1,3(2H)-dione (14) and 2-(3,4-dihydroxybenzylidene)-1H-indene-1,3(2H)-dione (17), were characterized as noncompetitive enzymes inhibitors, with IC50 values of 11 µmol L-1 and 3 µmol L-1, respectively. Docking and electrostatic potential surfaces investigations provided insight on the possible binding mode of the most active compounds within an allosteric site.


Asunto(s)
Inhibidores de Proteasas/síntesis química , Proteínas no Estructurales Virales/antagonistas & inhibidores , Virus del Nilo Occidental/enzimología , Sitio Alostérico , Catálisis , Hidroxilación , Indanos/síntesis química , Indanos/farmacología , Concentración 50 Inhibidora , Simulación del Acoplamiento Molecular , Inhibidores de Proteasas/química , Circonio
7.
J Dairy Sci ; 100(6): 4513-4527, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28365114

RESUMEN

The aim of this study was to use meta-analytical methods to estimate effects of adding exogenous fibrolytic enzymes (EFE) to dairy cow diets on their performance and to determine which factors affect the response. Fifteen studies with 17 experiments and 36 observations met the study selection criteria for inclusion in the meta-analysis. The effects were compared by using random-effect models to examine the raw mean difference (RMD) and standardized mean difference between EFE and control treatments after both were weighted with the inverse of the study variances. Heterogeneity sources evaluated by meta-regression included experimental duration, EFE type and application rate, form (liquid or solid), and method (application to the forage, concentrate, or total mixed ration). Only the cellulase-xylanase (C-X) enzymes had a substantial number of observations (n = 13 studies). Application of EFE, overall, did not affect dry matter intake, feed efficiency but tended to increase total-tract dry matter digestibility and neutral detergent fiber digestibility (NDFD) by relatively small amounts (1.36 and 2.30%, respectively, or <0.31 standard deviation units). Application of EFE increased yields of milk (0.83 kg/d), 3.5% fat-corrected milk (0.55 kg/d), milk protein (0.03 kg/d), and milk lactose (0.05 kg/d) by moderate to small amounts (<0.30 standard deviation units). Low heterogeneity (I 2 statistic <25%) was present for yields and concentrations of milk fat and protein and lactose yield. Moderate heterogeneity (I 2 = 25 to 50%) was detected for dry matter intake, milk yield, 3.5% fat-corrected milk, and feed efficiency (kg of milk/kg of dry matter intake), whereas high heterogeneity (I 2 > 50%) was detected for total-tract dry matter digestibility and NDFD. Milk production responses were higher for the C-X enzymes (RMD = 1.04 kg/d; 95% confidence interval: 0.33 to 1.74), but were still only moderate, about 0.35 standardized mean difference. A 24% numerical increase in the RMD resulting from examining only C-X enzymes instead of all enzymes (RMD = 1.04 vs. 0.83 kg/d) suggests that had more studies met the inclusion criteria, the C-X enzymes would have statistically increased the milk response relative to that for all enzymes. Increasing the EFE application rate had no effect on performance measures. Application of EFE to the total mixed ration improved only milk protein concentration, and application to the forage or concentrate had no effect. Applying EFE tended to increase dry matter digestibility and NDFD and increased milk yield by relatively small amounts, reflecting the variable response among EFE types.


Asunto(s)
Alimentación Animal , Fibras de la Dieta/metabolismo , Suplementos Dietéticos , Digestión/efectos de los fármacos , Enzimas/administración & dosificación , Leche/metabolismo , Animales , Bovinos , Celulasa/administración & dosificación , Industria Lechera , Dieta , Digestión/fisiología , Ingestión de Alimentos/efectos de los fármacos , Endo-1,4-beta Xilanasas/administración & dosificación , Femenino , Glucolípidos/metabolismo , Glicoproteínas/efectos de los fármacos , Glicoproteínas/metabolismo , Lactancia , Gotas Lipídicas , Proteínas de la Leche/metabolismo
8.
J Dairy Sci ; 100(6): 4587-4603, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28342607

RESUMEN

Forages are usually inoculated with homofermentative and facultative heterofermentative lactic acid bacteria (LAB) to enhance lactic acid fermentation of forages, but effects of such inoculants on silage quality and the performance of dairy cows are unclear. Therefore, we conducted a meta-analysis to examine the effects of LAB inoculation on silage quality and preservation and the performance of dairy cows. A second objective was to examine the factors affecting the response to silage inoculation with LAB. The studies that met the selection criteria included 130 articles that examined the effects of LAB inoculation on silage quality and 31 articles that investigated dairy cow performance responses. The magnitude of the effect (effect size) was evaluated using raw mean differences (RMD) between inoculated and uninoculated treatments. Heterogeneity was explored by meta-regression and subgroup analysis using forage type, LAB species, LAB application rate, and silo scale (laboratory or farm-scale) as covariates for the silage quality response and forage type, LAB species, diet type [total mixed ration (TMR) or non-TMR], and the level of milk yield of the control cows as covariates for the performance responses. Inoculation with LAB (≥105 cfu/g as fed) markedly increased silage fermentation and dry matter recovery in temperate and tropical grasses, alfalfa, and other legumes. However, inoculation did not improve the fermentation of corn, sorghum, or sugarcane silages. Inoculation with LAB reduced clostridia and mold growth, butyric acid production, and ammonia-nitrogen in all silages, but it had no effect on aerobic stability. Silage inoculation (≥105 cfu/g as fed) increased milk yield and the response had low heterogeneity. However, inoculation had no effect on diet digestibility and feed efficiency. Inoculation with LAB improved the fermentation of grass and legume silages and the performance of dairy cows but did not affect the fermentation of corn, sorghum, and sugar cane silages or the aerobic stability of any silage. Further research is needed to elucidate how silage inoculated with homofermentative and facultative heterofermentative LAB improves the performance of dairy cows.


Asunto(s)
Fermentación , Lactancia , Ácido Láctico/metabolismo , Lactobacillus/metabolismo , Ensilaje/microbiología , Aerobiosis , Animales , Bovinos , Digestión , Fabaceae/metabolismo , Femenino , Medicago sativa/metabolismo , Poaceae/metabolismo , Saccharum/metabolismo , Sorghum/metabolismo , Zea mays/metabolismo
9.
J Nanobiotechnology ; 14(1): 61, 2016 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-27465605

RESUMEN

BACKGROUND: In recent times, studies have demonstrated that carbon nanotubes are good candidates for use as vehicles for transfection of exogenous material into the cells. However, there are few studies evaluating the behavior of carbon nanotubes as DNA vectors and few of these studies have used multi-walled carbon nanotubes (MWCNTs) or carboxylated MWCNTs. Thus, this study aims to assess the MWCNTs' (carboxylated or not) efficiency in the increase in expression of the tetravalent vaccine candidate (TVC) plasmid vector for dengue virus in vitro using Vero cells, and in vivo, through the intramuscular route, to evaluate the immunological response profile. RESULTS: Multi-walled carbon nanotubes internalized by Vero cells, have been found in the cytoplasm and nucleus associated with the plasmid. However, it was not efficient to increase the messenger ribonucleic acid (mRNA) compared to the pure vaccine candidate associated with Lipofectamine(®) 2000. The in vivo experiments showed that the use of intramuscular injection of the TVC in combination with MWCNTs reduced the immune response compared to pure TVC, in a general way, although an increase was observed in the population of the antibody-producing B cells, as compared to pure TVC. CONCLUSIONS: The results confirm the data found by other authors, which demonstrate the ability of nanotubes to penetrate target cells and reach both the cytoplasm and the cell nucleus. The cytotoxicity values are also in accordance with the literature, which range from 5 to 20 µg/mL. This has been found to be 10 µg/mL in this study. Although the expression levels are higher in cells that receive the pure TVC transfected using Lipofectamine(®) 2000, the nanotubes show an increase in B-cells producing antibodies.


Asunto(s)
Anticuerpos Antivirales/biosíntesis , Linfocitos B/efectos de los fármacos , Vacunas contra el Dengue/administración & dosificación , Dengue/prevención & control , Nanotubos de Carbono/química , Transfección/métodos , Vacunación , Animales , Linfocitos B/inmunología , Linfocitos B/virología , Chlorocebus aethiops , Dengue/inmunología , Dengue/virología , Vacunas contra el Dengue/inmunología , Virus del Dengue/efectos de los fármacos , Virus del Dengue/inmunología , Modelos Animales de Enfermedad , Femenino , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Humanos , Lípidos/farmacología , Recuento de Linfocitos , Ratones , Ratones Endogámicos BALB C , Plásmidos/química , Plásmidos/metabolismo , Células Vero
10.
Rev. bras. anal. clin ; 43(2): 125-130, 2011. graf, tab
Artículo en Portugués | LILACS | ID: lil-605686

RESUMEN

0 diagnóstico da infecção pelo vírus da dengue é baseado, em grande parte dos casos, apenas no exame clínico do paciente, já que somente alguns poucos grandes centros possuem laboratórios clinicos que disponibilizam testes diagnósticos para confirmar sintomas clinicos de infecção. Atualmente, o diagnóstico laboratorial da dengue pode ser feito por diferentes tipos de testes. Entre eles estao os métodos de pesquisa sorológica, de isolamento viral, de detecção de antigenos virais e do genoma viral. 0 desenvolvimento continuado de testes diagnósticos baratos, sensíveis, especificos e de fácil execucção, que sejam capazes de proporcionar diagnóstico precoce da infecção pelos virus da dengue, é ainda uma necessidade. Existem também outros obstáculos que nao são especificamente relacionados ao desenvolvimento tecnológico dos métodos diagnósticos. Por exemplo, a infra-estrutura dos laboratórios, o treinamento do pessoal técnico e a capacidade de pesquisa ainda são limitados em muitas partes do Brasil e do mundo, onde a dengue é endêmica. Laboratórios clinicos, principalmente os que atendem às regiões de maior incidência da dengue, devem se interar de todos os métodos diagnósticos disponíveis para a rotina atualmente e definir qual se adapta melhor às suas condições de trabalho e população atendida, com o intuito de salvarvidas.


The diagnosis of the infection caused by the dengue virus relies in most cases on the clinical examination of the patient, since only a few major centers have clinical laboratories providing diagnostic tests to confirm the clinical symptons of infection. Currently, routine laboratory diagnosis can be done by different kinds of testing. Among them the methods ofserological research, virus isolation, detection of viral antigens and of viral genome are included. The continued development of diagnostic tests that are cheap, sensitive, specific, easy to perform, and that are capable of giving early diagnosis of the dengue virus infection is still a need. There are also other obstacles not specifically related to the technological development ofdiagnostic methods. For instance, the laboratories' infrastructure, the workers training and the research capacity are still limited in many parts of Brazil and the world, where dengue is endemic. Clinical laboratories, specially those situated in regions with high incidence of dengue, should be aware of all the diagnostic methods available four routine nowadays, and choose the best one that fulfills their working conditions and populations served, in order to save lives.


Asunto(s)
Infecciones por Arbovirus , Arbovirus/aislamiento & purificación , Técnicas de Laboratorio Clínico , Dengue/diagnóstico , Ensayo de Inmunoadsorción Enzimática , Virus/aislamiento & purificación
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