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1.
J Environ Manage ; 347: 119149, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37783087

RESUMEN

The recent agricultural expansion in the Matopiba region, Brazil's new agricultural frontier, has raised questions about the risk of increasing soil organic carbon (SOC) loss as large areas of native vegetation (NV; i.e., Cerrado biome) have been replaced by large-scale mechanized agriculture. Although sustainable managements, such as integrated crop-livestock (ICL) systems, are considered strategic to counterbalance the SOC loss associated with land-use change (LUC) while keeping food production, little is known about their long-term effects on SOC stocks in the Matopiba region. To this end, we used the DayCent model to simulate the effects of converting the management commonly used in this region, i.e., soybean-cotton rotation under no-tillage (NT), into ICL systems with distinct levels of intensification (e.g., crop rotations: soybean-pasture and soybean-pasture-cotton; soil and crop management: grass irrigation, scarification/harrowing, and length of grass cultivation) on long term SOC dynamics. Additionally, data from two projected climate scenarios: SSP2-4.5 [greenhouse gases emissions (GHG) will not change markedly over time and global temperature will increase by 2.0 °C by 2060] and SSP5-8.5 (marked changes in GHG emissions are expected to occur resulting in an increase of 2.4 and 4.4 °C in global temperature in the middle and at the end of the century) were included in our simulations to evaluate climate change effects on SOC dynamics in this region. Based on a 50-yr-time frame simulation, we observed that SOC stocks under ICL systems were, on average, 23% and 47% higher than in the NV (36.9 Mg ha-1) and soybean-cotton rotation under NT (30.9 Mg ha-1), respectively. Growing grasses interlaid with crops was crucial to increase SOC stocks even when disruptive soil practices were followed. Although the irrigation of grass resulted in an early increase of SOC stocks and a higher pasture stoking rate, it did not increase SOC stocks in the long term compared to non-irrigated treatments. The SSP2-4.5 and SSP5-8.5 climate scenarios had little effects on SOC dynamics in the simulated ICL systems. However, additional SOC loss (∼0.065 Mg ha-1 yr-1) is predicted to occur if the current management is not improved. These findings can help guide management decisions for the Matopiba region, Brazil, to alleviate the anthropogenic pressure associated with agriculture development. More broadly, they confirm that crop-livestock integration in croplands is a successful strategy to regenerate SOC.


Asunto(s)
Cambio Climático , Suelo , Carbono/análisis , Brasil , Biodiversidad , Temperatura , Agricultura/métodos , Poaceae
2.
Heliyon ; 9(3): e14642, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37020934

RESUMEN

The present work demonstrates that conductive carbon paint, used for sample preparation in electron microscopy, can be a more straightforward and as-effective substitute for the metallic layer deposition usually used for the electrodeposition of metallic nanowires within porous membranes. AFM images demonstrated the good surface quality of the carbon layer. Raman spectroscopy confirmed the high crystallinity of carbon and high density of π-electrons. The electrical conductivity of the carbon layer was estimated using the linear sweep voltammetry technique. This new cathode was employed to grow continuous (Ni) and composition-modulated (Ni/Cu) nanowires within alumina templates, starting from aqueous solutions of Ni2+ and Cu2+ mixed salts. The obtention of metallic copper and nickel, and their separation can be readily observed by scanning electron microscopy and elemental mapping by EDS.

3.
Braz J Biol ; 83: e269317, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36722663

RESUMEN

Bacteria may be the initial cause of certain pathologies as well as a secondary agent responsible for the development of complications such as pressure ulcer infections. Pressure ulcers are a persistent health problem, especially in immunocompromised patients, and associated with infection by opportunistic microorganisms with antimicrobial resistance, such as Klebsiella pneumoniae, highlight the need for the development of new antimicrobial approaches. Thus, the aim of this study was to evaluate the antibacterial and anti-adherent activity of Origanum vulgare L. (oregano) essential oil against Klebsiella pneumoniae strains, as well as the effect of its association with synthetic antimicrobials. To this end, the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) analyses were performed on microdilution plates. The assay of the Minimum Inhibitory Adherence Concentration (MIAC), with test tubes. As well as, the association study through the infusion disc method containing ampicillin (AMP), gentamicin (GEN), ciprofloxacin (CIP) and ceftriaxone (CEF). Therefore, it was possible to obtain that the essential oil of oregano presents antimicrobial and bactericidal activity, with MIC ranging between 128µg/mL and 256 µg/mL and MBC between 256 µg/mL and 512 µg/mL, on the tested K. pneumoniae strains. When used in association with ampicillin and gentamicin, oregano essential oil showed synergistic effect for some strains. Therefore, it is observed that the tested essential oil can act as a promising antibacterial in the treatment of diseases caused by K. pneumoniae.


Asunto(s)
Aceites Volátiles , Origanum , Humanos , Klebsiella pneumoniae , Antibacterianos/farmacología , Ampicilina , Gentamicinas , Aceites Volátiles/farmacología
4.
Int Endod J ; 45(12): 1080-90, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22747502

RESUMEN

AIM: To compare cells from normal and inflamed human dental pulps regarding the presence of stem cells, their proliferation and differentiation potential. METHODOLOGY: Human dental pulp stem cells (hDPSCs) were isolated from normal (DPSC-N) and inflamed dental pulps (DPSC-I). They were compared in respect to proliferation (MTT assay), morphology and STRO-1 expression. STRO-1-positive cells were subject to proliferation (MTT and CFU counting) and morphological analyses and then submitted to odonto-osteogenic, adipogenic and condrogenic differentiation. Differentiated cells were evaluated concerning morphology and the expression, by qRT-PCR, of BSP, LPL and SOX-9 genes. The amount of mineralized matrix produced after odonto-osteogenic differentiation was compared with quantitative Alizarin Red staining. RESULTS: No difference was observed in the morphology and in the proliferation rate of DPSC-N and DPSC-I either before or after separation of STRO-1-positive cells. These cells represented 0.46% (±0.14) and 0.43% (±0.19) of the cell population from normal and inflamed dental pulps, respectively. Both DPSC-N and DPSC-I were capable of differentiating under the three assayed conditions and presented similar patterns for BSP, LPL and SOX-9 expression. Mineralized matrix production was also compatible. In all the quantitative experiments, differences were found between cells from each patient, either from normal or from inflamed pulps. Nonetheless, there was no statistical difference between these two groups. CONCLUSION: The morphology, proliferation rate and differentiation potential of DPSC-I were similar to the observed in DPSC-N, thus demonstrating that the inflammatory process did not affect the stem cell properties that were assessed.


Asunto(s)
Pulpa Dental/citología , Células Madre Mesenquimatosas , Pulpitis/patología , Adipogénesis , Adolescente , Adulto , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Condrogénesis , Citometría de Flujo , Humanos , Inmunofenotipificación , Sialoproteína de Unión a Integrina/biosíntesis , Lipoproteína Lipasa/biosíntesis , Metaloproteinasa 3 de la Matriz/biosíntesis , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/fisiología , Osteogénesis , Regeneración , Factor de Transcripción SOX9/biosíntesis , Adulto Joven
5.
J Cell Physiol ; 222(3): 606-11, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19957302

RESUMEN

Inorganic polyphosphate (poly P) is a polymer of phosphate residues that has been shown to act as modulator of some vertebrate cathepsins. In the egg yolk granules of Rhodnius prolixus, a cathepsin D is the main protease involved in yolk mobilization and is dependent on an activation by acid phosphatases. In this study, we showed a possible role of poly P stored inside yolk granules on the inhibition of cathepsin D and arrest of yolk mobilization during early embryogenesis of these insects. Enzymatic assays detected poly P stores inside the eggs of R. prolixus. We observed that micromolar poly P concentrations inhibited cathepsin D proteolytic activity using both synthetic peptides and homogenates of egg yolk as substrates. Poly P was a substrate for Rhodnius acid phosphatase and also a strong competitive inhibitor of a pNPPase activity. Fusion events have been suggested as important steps towards acid phosphatase transport to yolk granules. We observed that poly P levels in those compartments were reduced after in vitro fusion assays and that the remaining poly P did not have the same cathepsin D inhibition activity after fusion. Our results are consistent with the hypothesis that poly P is a cathepsin D inhibitor and a substrate for acid phosphatase inside yolk granules. It is possible that, once activated, acid phosphatase might degrade poly P, allowing cathepsin D to initiate yolk proteolysis. We, therefore, suggest that degradation of poly P might represent a new step toward yolk mobilization during embryogenesis of R. prolixus.


Asunto(s)
Fosfatasa Ácida/metabolismo , Catepsina D/metabolismo , Proteínas del Huevo/metabolismo , Yema de Huevo/enzimología , Proteínas de Insectos/metabolismo , Polifosfatos/metabolismo , Rhodnius/enzimología , Ácido Anhídrido Hidrolasas/metabolismo , Animales , Catepsina D/antagonistas & inhibidores , Yema de Huevo/efectos de los fármacos , Proteínas de Insectos/antagonistas & inhibidores , Pepstatinas/farmacología , Inhibidores de Proteasas/farmacología , Transporte de Proteínas , Proteínas Recombinantes/metabolismo , Rhodnius/efectos de los fármacos , Rhodnius/embriología
6.
Inflamm Res ; 59(2): 129-34, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19701605

RESUMEN

OBJECTIVE AND DESIGN: To evaluate plasma sTNFR-1 and IL-6 levels and correlate with hand grip in the institutionalized and community living Brazilian elderly. MATERIAL: A convenience sample of 110 elderly women (71.17 + or - 7.44 years) was selected. Plasma sTNFR-1 and IL-6 levels were measured by ELISA. For the measurement of hand grip, a JAMAR dynamometer was used. RESULTS: Plasma concentrations of inflammatory markers were significantly higher in institutionalized elderly (sTNFR-1: 479 + or - 22 pg/mL; IL-6: 6.3 + or - 0.8 pg/mL) than in community-dwelling elderly (sTNFR-1: 329 + or - 24 pg/mL; IL-6: 2.5 + or - 0.4 pg/mL; P < 0.0001). Institutionalized elderly had reduced hand grip (15 + or - 0.8 Kgf) in comparison to community dwelling elderly (23 + or - 0.6 Kgf; P < 0.05). When individuals were subdivided in age groups, sTNFR-1 was higher in community dwelling versus institutionalized elderly in the 60-70 age range. CONCLUSIONS: Our results demonstrate that being institutionalized has an impact on levels of inflammatory markers.


Asunto(s)
Inflamación/sangre , Institucionalización , Receptores Tipo I de Factores de Necrosis Tumoral/sangre , Características de la Residencia , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Brasil , Estudios Transversales , Femenino , Fuerza de la Mano/fisiología , Humanos , Vida Independiente , Interleucina-6/sangre , Persona de Mediana Edad , Dinamómetro de Fuerza Muscular , Factor de Necrosis Tumoral alfa/sangre
7.
Int J Pharm ; 591: 120001, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33141086

RESUMEN

The aim of this study was to develop and characterize a double layer biomembrane for dual drug delivery to be used for the treatment of wounds. The membrane was composed of chitosan, hydroxypropyl methylcellulose and lidocaine chloride (anesthetic drug) in the first layer, and of sodium alginate-polymyxin B sulphate (antibiotic) nanoparticles as the second layer. A product with excellent thickness (0.01-0.02 mm), adequate mechanical properties with respect to elasticity, stiffness, tension, and compatible pH for lesion application has been successfully obtained. The incorporation of the drugs was confirmed analysing the membrane cross-sections by scanning electron microscopy. A strong interaction between the drugs and the functional groups of respective polymers was confirmed by Fourier-Transform Infrared Spectroscopy, thermal analysis and X-ray diffraction. Microbiological assays showed a high antimicrobial activity when polymyxin B was present to act against the Staphylococcus aureus and Pseudomonas aeruginosa strains. Low cytotoxicity observed in a cell viability colorimetric assay and SEM analysis suggest biocompatibility between the developed biomembrane and the cell culture. The in vivo assay allowed visualizing the healing potential by calculating the wound retraction index and by histological analysis. Our results confirm the effectiveness of the developed innovative biomaterial for tissue repair and regeneration in an animal model.


Asunto(s)
Quitosano , Nanopartículas , Alginatos , Animales , Vendajes , Lidocaína , Polimixinas , Espectroscopía Infrarroja por Transformada de Fourier , Cicatrización de Heridas
8.
Int J Biol Macromol ; 140: 761-770, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31434004

RESUMEN

Lipase B from Candida antarctica (CalB) is the most widely used lipase, including in many industrial sectors, such as in biodiesel and pharmaceuticals production. CalB has been produced by heterologous expression using Pichia pastoris under PGK constitutive promoter (named LipB). Here, we have studied the structural features of commercial CalB and LipB enzymes using circular dichroism and fluorescence under different conditions. In the presence of denaturing agents CalB was more stable than LipB, in contrast, at increasing temperatures, LipB was more thermostable than CalB. Mass spectrometry data indicates that both enzymes have an insertion of amino acids related to α-factor yeast signal, however LipB enzyme showed the addition of nine residues at the N-terminal while CalB showed only four residues. Molecular modeling of LipB showed the formation of an amphipathic α-helix in N-terminal region that was not observed in CalB. This data suggests that this new α-helix possess could be involved in LipB thermostability. These results associated with new structural studies may provide information to the design of novel biocatalysts.


Asunto(s)
Candida/enzimología , Proteínas Fúngicas/química , Lipasa/química , Proteínas Recombinantes de Fusión , Secuencia de Aminoácidos , Candida/genética , Activación Enzimática , Estabilidad de Enzimas , Proteínas Fúngicas/genética , Proteínas Fúngicas/aislamiento & purificación , Proteínas Fúngicas/metabolismo , Hidrólisis , Lipasa/genética , Lipasa/aislamiento & purificación , Lipasa/metabolismo , Modelos Moleculares , Conformación Proteica , Relación Estructura-Actividad , Temperatura , Termodinámica
9.
Water Sci Technol ; 57(12): 1915-20, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18587178

RESUMEN

Tritium content in the leachate of sanitary landfills, in concentrations well above those observed in global precipitation, can be used as a tracer for the evaluation of the contamination of groundwater in piezometers of the landfills and in neighbouring tubular wells. This possibility was first investigated in Brazil for sanitary landfills in the region of Belo Horizonte City. Tritium levels together with the content of metals present in water and the measurement of soil electrical conductivity, proved to be valuable for these studies and also as a tracer for hydrodynamic studies of the surface water in the Ressaca creek.


Asunto(s)
Eliminación de Residuos , Tritio/análisis , Contaminación Química del Agua/análisis , Abastecimiento de Agua/análisis , Brasil , Geografía , Contaminantes Químicos del Agua/análisis
10.
Transplant Proc ; 39(2): 346-7, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17362726

RESUMEN

OBJECTIVE: To evaluate changes in the profile of potential dead donors brain as to age, gender, and cause of death between 1988 to 2004, as well as the notification rates of potential donors, the donation itself, and family non-authorization. PATIENTS AND METHODS: Records of 2,757 potential donors were reviewed in three periods: I: 1988-1992 (n = 465), II: 1993-1997 (n = 567), and III: 1998-2004 (n = 1,725). RESULTS: The mean age which was similar in periods I and II (30.8 and 29.8 years), increased in period III (38.3 + 18.5 years); (P < .05). The frequency of male donors decreased from 71% and 69%, to 57% (P < .05). The cranium-encephalic trauma decreased from 63.2% and 54.7% to 34.8% (P < .05), while the brain-vascular accidents (CVA) increased from 28.0% and 34.5% to 49.4% (P < .05). The rate of potential donors notified increased from 10.7 per million population per year (pmp/y) and 11.9 to 24.6 pmp/y, while the donation rate increased from 4.4 pmp/y (42.4%) and 7.7 pmp/y (64.3%) to 9.6 pmp/y (38.8%), in periods I, II and III, respectively. The family's nonauthorization changed from 41.5% and 21.7% to 31.9%. CONCLUSIONS: We observed a similar trend as that in developed countries, that is, a significant increases in the ages of potential donors, in the proportion of female donors, and in the CVA brain death. There has been a significant increase in the notification rate and the donation itself, without a significant modification in family nonauthorization rate.


Asunto(s)
Muerte Encefálica , Donantes de Tejidos/estadística & datos numéricos , Adulto , Brasil , Causas de Muerte , Familia , Femenino , Humanos , Masculino , Estudios Retrospectivos
11.
Transplant Proc ; 39(2): 381-2, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17362736

RESUMEN

In 2002, it was established a system of urgency priority for kidney transplantations in cases with no vascular or peritoneal access for dialysis. The aims of this article are to describe the system in the organ donation and procurement agency (CNCDO) as well as to show the results to date. We reviewed cases of urgency priority request for kidney transplantation addressed to the CNCDO from May 2002 to August 2005. Within this period the CNCDO received 35 urgency priority requests for kidney transplantation (mean, 1 every 1.2 months). Thirty-one (88%) were accepted as urgent, and only 4 (11%) were refused. Among the 31 accepted, 26 (83%) had the transplantation performed in an average time of 19.6 days (range, 1-90), representing only 3.2% of all cadaveric kidney transplantations during that period.


Asunto(s)
Trasplante de Riñón/estadística & datos numéricos , Obtención de Tejidos y Órganos/estadística & datos numéricos , Listas de Espera , Brasil , Humanos , Estudios Retrospectivos , Factores de Tiempo
12.
Transplant Proc ; 39(2): 344-5, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17362725

RESUMEN

INTRODUCTION: There are few reports in the literature analyzing brain death epidemiology in suicides, or the rate of donation and family authorization in such situations. OBJECTIVE: The objectives of this study were to analyze the frequency of suicide as a cause of brain death and to compare the donation rates among this population with other causes of brain death. PATIENTS AND METHODS: We reviewed records from 2627 potential donors between 1988 and 2004. RESULTS: Within that period, 101 (3.8%) cases of brain death were recorded as suicides. The mean age was significantly lower (P < .05) in cases of suicide than for other causes (26.2 + 11.1 vs 34.4 + 16.5 years); there was a male prevalence (76.2% vs 60.8%). As to suicides, the donation rate was significantly higher than in other situations (62.3% vs 43.8%). This was due to a lower rate of negative family responses (17.8% vs 32.1%). CONCLUSIONS: Suicide is a frequent cause of brain death (3.8%), mainly among young men. The donation rate in this group is higher than that due to other causes of death because of a lower negative response rate by the family. The explanation remains to be clarified for such a low refusal rate for organ donation by the relatives of potential donors due to suicide.


Asunto(s)
Suicidio/estadística & datos numéricos , Donantes de Tejidos/estadística & datos numéricos , Adolescente , Adulto , Muerte Encefálica , Causas de Muerte , Familia , Humanos , Persona de Mediana Edad
13.
Transplant Proc ; 39(2): 399-400, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17362740

RESUMEN

INTRODUCTION: There are still few publications about brain death caused by electric shock and the use of organs for donation in this situation. We sought to present our experience, with brain dead pediatric donors caused by electric shock. MATERIAL AND METHODS: Notification registers of potential donors were analyzed from 1998 to 2005. RESULTS: During this period, 2086 potential donors were secured, of whom 307 (14.7%) were less than 18 years old. Four pediatric potential donors (1.3%) suffered brain death due to anoxia by electric shock. Six kidneys, three livers, six corneas, and three heart valves were used for transplantation. The hearts and the lungs were not offered, because of a lack of compatible patients on the waiting list. The pediatric donors showed significant alterations of cardiac enzymes and two had altered liver enzymes. CONCLUSION: Brain death caused by electric shock is not a contraindication for organ donation. Follow-up of the recipients is necessary to determine if the transplants were successful.


Asunto(s)
Muerte Encefálica , Traumatismos por Electricidad , Donantes de Tejidos/estadística & datos numéricos , Adolescente , Brasil , Niño , Humanos , Hipoxia/etiología , Sistema de Registros , Estudios Retrospectivos , Factores de Tiempo
14.
Genet Mol Res ; 6(4): 766-98, 2007 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-18058704

RESUMEN

Flagella are constructed and maintained through the highly conserved process of intraflagellar transport (IFT), which is a rapid movement of particles along the axonemal microtubules of cilia/flagella. Particles that are transported by IFT are composed of several protein subunits comprising two complexes (A and B), which are conserved among green algae, nematodes, and vertebrates. To determine whether or not homologues to members of the IFT complex proteins are conserved in Leishmania spp, we scanned genomes, transcriptomes and proteomes of Leishmania species in a search for putative IFT factors, which were then identified in silico, compared, cataloged, and characterized. Since a large proportion of newly identified genes in L. major remain unclassified, with many of these being potentially Leishmania- (or kinetoplastid-) specific, there is a need for detailed analyses of homologs/orthologs that could help us understand the functional assignment of these gene products. We used a combination of integrated bioinformatics tools in a pathogenomics approach to contribute to the annotation of Leishmania genomes, particularly regarding flagellar genes and their roles in pathogenesis. This resulted in the formal in silico identification of eight of these homologs in Leishmania (IFT subunits, 20, 27, 46, 52, 57, 88, 140, and 172), along with others (IFTs 71, 74/72, and 81), as well as sequence comparisons and structural predictions. IFT, an important flagellar pathway in Leishmania, begins to be revealed through screening of trypanosomatid genomes; this information could also be used to better understand fundamental processes in Leishmania, such as motility and pathogenesis.


Asunto(s)
Biología Computacional/métodos , Flagelos/genética , Genes Protozoarios , Genoma de Protozoos , Leishmania/genética , Secuencia de Aminoácidos , Animales , Transporte Biológico , Cilios/genética , Secuencia Conservada , Datos de Secuencia Molecular , Estructura Terciaria de Proteína , Subunidades de Proteína/química , Subunidades de Proteína/genética , Proteínas Protozoarias/química , Proteínas Protozoarias/genética , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
15.
Arq. bras. med. vet. zootec. (Online) ; 73(6): 1413-1421, Nov.-Dec. 2021. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355684

RESUMEN

The objective this study was to identify differences in the morphogenic patterns of four Urochloa brizantha cultivars (marandu, piatã, xaraés and paiaguás grasses) during the stockpiling period. A completely randomized design was used, with three replications, in experimental plots of 9m². The evaluations took place over 2 years. The grasses were stockpiled for 92 (Year 1) and 95 (Year 2) days. The leaf appearance rate of paiaguás grass was higher, compared to other grasses. In Year 1, the stem elongation rate of xaraés grass was higher than other grasses. At the end of stockpiling period of Year 1, the tiller population density (TPD) was higher in the paiaguás grass, intermediate in the xaraés and marandu grasses and lower in the piatã grass. At the end of the stockpiling period in Year 2, TPD was higher in the paiaguás grass canopy, intermediate in the marandu and piatã grasses canopies, and lower in the xaraés grass canopy. Paiaguás grass has greater leaf growth during the stockpiling period and is therefore suitable for use under stockpiled grazing. Xaraés grass has high stem elongation during the stockpiling period, which is why its use under stockpiled grazing must be accompanied by adjustments in pasture management.(AU)


O objetivo deste estudo foi identificar diferenças nos padrões morfogênicos de quatro cultivares de Urochloa brizantha (marandu, piatã, xaraés e paiaguás) durante o período de diferimento. Foi utilizado o delineamento inteiramente ao acaso, com três repetições, em parcelas experimentais de 9m². As avaliações ocorreram por dois anos. Os capins foram diferidos por 92 (Ano 1) e 95 (Ano 2) dias. A taxa de aparecimento foliar do capim-paiaguás foi maior, em comparação aos demais capins. No Ano 1, a taxa de alongamento do colmo do capim-xaraés foi superior aos demais capins. No final do diferimento do Ano 1, a densidade populacional de perfilho (DPP) foi maior no capim-paiaguás, intermediária nos capins xaraés e marandu e inferior no capim-piatã. No fim do período de diferimento do Ano 2, a DPP foi superior no dossel de capim-paiaguás, intermediária nos dosséis dos capins marandu e piatã, e menor no dossel de capim-xaraés. O capim-paiaguás tem maior crescimento foliar durante o período de diferimento, sendo, portanto, apropriado para uso sob pastejo diferido. O capim-xaraés apresenta elevado alongamento de colmo durante o período de diferimento, razão pela qual seu uso sob pastejo diferido deve vir acompanhado de ajustes no manejo da pastagem.(AU)


Asunto(s)
Tallos de la Planta , Brachiaria/crecimiento & desarrollo , Morfogénesis/fisiología
16.
Arq. bras. med. vet. zootec. (Online) ; 73(6): 1403-1412, Nov.-Dec. 2021. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355685

RESUMEN

The objective was to identify lowering strategies for Urochloa brizantha cv. Marandu in the beginning of the stockpiling period that increase forage production and improve the structure of stockpiled canopies. Three lowering strategies were evaluated: maintenance of marandu palisade grass with 15cm four months before the stockpiling period; maintenance of palisade grass with 30cm for four months, and lowering to 15cm before the stockpiling period; and maintaining of palisade grass at 45cm for four months, and lowering to 15cm before the stockpiling period. The experimental design was completely randomized, with four replications. At the end of stockpiling, the number of reproductive tillers and forage mass were higher in the canopy under 15/15cm than in the others; the percentage of live leaf was higher in the canopy under 45/15cm than under 15/15cm. Forage production during the stockpiling period was higher in the canopy under 15/15cm and lower in the under 45/15cm. Maintaining 15cm marandu palisadegrass for four months before the stockpiling period increases forage production during this period. The lowering of the marandu palisadegrass from 45 to 15cm at the beginning of the stockpiling period improves the structure of the stockpiled canopy.(AU)


Objetivou-se identificar estratégias de rebaixamento da Urochloa brizantha cv. Marandu no início do diferimento, as quais resultem em aumento da produção e em melhoria da estrutura do dossel diferido. Foram avaliadas três estratégias de rebaixamento no início do diferimento: manutenção do capim-marandu com 15cm por quatro meses antes do início do diferimento; manutenção do capim-marandu com 30cm por quatro mese, e rebaixamento para 15cm no início do diferimento; e manutenção do capim com 45cm por quatro meses e rebaixamento para 15cm no início do diferimento. O delineamento foi inteiramente ao acaso, com quatro repetições. No fim do diferimento, o número de perfilho reprodutivo e a massa de forragem foram superiores no dossel sob 15/15cm do que nos demais; a percentagem de folha viva foi maior no dossel sob 45/15cm do que sob 15/15cm. A produção de forragem durante o diferimento foi superior no dossel sob 15/15cm e inferior no sob 45/15cm. A manutenção do capim-marandu com 15cm por quatro meses antes do período de diferimento aumenta a produção de forragem neste período. O rebaixamento do capim-marandu de 45 para 15cm no início do diferimento melhora a estrutura do dossel diferido.(AU)


Asunto(s)
Producción de Cultivos , Hojas de la Planta/anatomía & histología , Brachiaria/crecimiento & desarrollo
17.
Braz J Biol ; 76(3): 645-55, 2016 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-27143060

RESUMEN

Considering the physiological importance and need of greater morphophysiological knowledge of adrenal glands, the aims of present study were compare the morphometric data between left and right adrenal of male and female; perform a histological, scanning and transmission electron microscopy study showing tissue constitution of glands; finally, in order to define the presence and correct site of the cytochrome P450c17 expression in adrenal glands, immunohistochemical study of this enzyme was performed in 18 adrenal glands (right n=9 and left n=9) of nine adult Galea spixii (four males and five females). Right adrenal was more cranially positioned than left adrenal; dimensions (weight, length and width) of right adrenal was larger than left adrenal; no differences between male and female body and adrenal measurements were found; the morphology of cells and different amounts of lipid droplets may be related to the different demands of steroid hormones production, related to each zone of the adrenal cortex; and, the cytochrome P450c17 immunolocalization in fasciculate and reticular zone may be related with synthesis of 17-hydroxy-pregnenolone, 17-hydroxy-progesterone, dehydroepiandrosterone or androstenedione.


Asunto(s)
Glándulas Suprarrenales/anatomía & histología , Roedores/anatomía & histología , Animales , Femenino , Cobayas , Masculino
18.
Transplant Proc ; 37(1): 425-7, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15808665

RESUMEN

AIM: To study the effects of N-acetylcysteine and ischemic preconditioning on the portal triad clamping compared to arterial and portal clamping alone. METHODS: Eighty EPM 1-Wistar rats were randomized into two groups, depending on inclusion (Group 1) or not (Group 2) of the bile duct in the hepatic vascular pedicle occlusion. Each group was divided into four subgroups as follows. IR 1: 20 minutes after celiotomy, the pedicle containing vascular elements and bile duct to the left lateral and median liver lobes was occluded for 40 minutes, followed by 30 minutes of reperfusion. IPC 1: after 10 minutes of ischemia and 10 minutes of reperfusion, the ischemic preconditioning period, the rats were submitted to the same procedure described for IR 1 Group. NAC 1: the rats received N-acetylcysteine (150 mg/kg) 15 minutes before 40 minutes of ischemia and 5 minutes before 30 minutes of reperfusion. SHAM 1: The hepatic pedicle for the lateral and median liver lobes was dissected after 20 minutes, the bile duct alone was clamped for 40 minutes, and released for an additional 30 minutes. In the IR 2, IPC 2, and NAC 2 groups, ischemia was achieved with an exclusive vascular occlusion. SHAM 2: dissection and observation for 90 minutes. The blood was sampled for liver enzyme levels. Statistical analysis was done (P

Asunto(s)
Acetilcisteína/farmacología , Conductos Biliares/fisiología , Precondicionamiento Isquémico , Circulación Hepática/fisiología , Daño por Reperfusión/prevención & control , Alanina Transaminasa/metabolismo , Fosfatasa Alcalina/metabolismo , Animales , Aspartato Aminotransferasas/metabolismo , Bilirrubina/metabolismo , Circulación Hepática/efectos de los fármacos , Masculino , Sistema Porta , Ratas , Ratas Wistar , gamma-Glutamiltransferasa/metabolismo
19.
Braz J Biol ; 65(3): 483-94, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16341427

RESUMEN

The aim of this study was to describe the anatomy and ontogeny of Pterodon emarginatus seed using the usual techniques. The ovules are campilotropous, crassinucelate, and bitegmic. The following processes occur during integument development: anticlinal divisions and phenolic compound accumulations in the exotesta, whose cells become palisade; predominantly periclinal divisions and cell expansion in the mesotesta, where the rapheal bundle differentiates; differentiation of the hourglass-cell layer adjacent to the palisade; fusion of outer and inner integuments, which remain individualized structures only at the micropylar end; and intense pectin impregnation in the mesotesta thicker walls with lignification restricted to the xylem. At the hilar pole, the Faboideae seed characteristic structure develops, with double palisade layer, subhilar parenchyma, and tracheid bar. The younger nucellus shows thicker pectic cell walls and is consumed during seed formation. The endosperm is nuclear and, after cellularization, shows peripheral cells with dense lipid content; the seeds are albuminous. The axial embryo shows fleshy cotyledons, which accumulate lipid and protein reserves; starch is rare. Although the seed structure is characteristic of the Fabaceae, the inner integument coalesces into the outer integument without being reabsorbed.


Asunto(s)
Fabaceae/anatomía & histología , Semillas/anatomía & histología , Fabaceae/citología , Fabaceae/crecimiento & desarrollo , Semillas/citología , Semillas/crecimiento & desarrollo
20.
Animal ; 9(2): 362-72, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25256316

RESUMEN

The objective of this study was to evaluate the fatty acid profile and qualitative characteristics of meat from feedlot young bulls fed ground soybean or ground cottonseed, with or without supplementation of vitamin E. A total of 40 Red Norte young bulls, with an initial average age of 20 months, and an initial average BW of 339±15 kg, were allotted in a completely randomized design using a 2×2 factorial arrangement, with two oilseeds, and daily supplementation or not of 2500 IU of vitamin E. The experimental period was for 84 days, which was preceded by an adaptation period of 28 days. The treatments were ground soybean (SB), ground soybean plus vitamin E (SBE), ground cottonseed (CS) and ground cottonseed plus vitamin E (CSE). The percentage of cottonseed and soybean in the diets (dry matter basis) was 24% and 20%, respectively. Diets were isonitrogenous (13% CP) and presented similar amount of ether extract (6.5%). The animals were slaughtered at average live weight of 464±15 kg, and samples were taken from the longissimus dorsi muscle for the measurement of fatty acid concentration and the evaluation of lipid oxidation and color of the beef. Before fatty acid extraction, muscle tissue and subcutaneous fat of the longissimus dorsi were separated to analyze fatty acid profile in both tissues. Supplementation of vitamin E did not affect fatty acid concentration, lipid oxidation and color (P>0.05). Subcutaneous fat from animals fed CS diet had greater C12:0, C16:0 and C18:0 contents (P<0.03). In addition, CS diets reduced the C18:1 and C18:2 cis-9, trans-11 contents in subcutaneous fat (P<0.05). The muscle from animals fed CS tended to higher C16:0 and C18:0 contents (P<0.11), and decreased C18:1, C18:2 cis-9, trans-11 and C18:3 contents (P<0.05) compared with SB. The Δ9-desaturase index was greater in muscle from animals fed SB (P<0.01). At 42 days of age, meat from cattle fed SB had a greater lipid oxidation rate (P<0.05). Meat from animals fed SB diets had less lightness and redness indices than meat from animals fed CS diets after 14 days of age. In conclusion, the addition of ground cottonseed in the finishing diets did increase the saturated fatty acid content of the longissimus dorsi. However, animals fed cottonseed exhibited greater lightness and redness of beef. In this study, the addition of vitamin E did not affect qualitative characteristics of meat.


Asunto(s)
Alimentación Animal/análisis , Bovinos/fisiología , Suplementos Dietéticos , Ácidos Grasos/metabolismo , Carne/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Peso Corporal , Aceite de Semillas de Algodón , Dieta/veterinaria , Ácidos Grasos/análisis , Metabolismo de los Lípidos , Masculino , Carne/normas , Semillas , Glycine max , Grasa Subcutánea/metabolismo , Vitamina E/administración & dosificación
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