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1.
Environ Monit Assess ; 196(4): 358, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38470549

RESUMO

Gullies are significant contributors to soil degradation in several regions of Brazil, including Minas Gerais, where erosion processes have caused soil loss. The characterization of erosion processes is crucial for the application of measures for recovering degraded areas and reducing erosion impacts. This study models soil loss with the use of InVEST software and assesses the impact of three different scenarios, namely (1) implementation of soil conservation practices and replacement of pasture areas for temporary agriculture, (2) reforestation of pasture areas, and (3) preservation of ciliary forests. Soil loss, sediment exportation, retention, and deposition for the present scenario (2019), as well as the three aforementioned hypothetical scenarios, were estimated. In the present scenario, the estimated mean annual soil loss was 2.75 t/ha year, with 1,449.54 t/year sediment exportation, 9,042.13 t/year retention, and 1,449.54 t/year deposition. The model predicted scenario 1 would result in 2.23 t/ha year mean annual soil loss, 1,300.59 t/year sediment exportation, 9,191.08 t/year retention, and 11,755.76 t/year deposition. Scenario 2 showed 1.92 t/ha year mean annual soil loss, 1,046.69 t/year sediment exportation, 9,444.98 t/year retention, and 10,229.77 t/year deposition, whereas the results for scenario 3 were 2.36 t/ha year, 616.65 t/year, 9,862.06 t/year, and 13,206.47 t/year, respectively. Reforestation and preservation of ciliary forests, along with soil conservation practices, were effective measures for reducing soil loss. Such findings are valuable for the management of areas degraded by erosion processes.


Assuntos
Conservação dos Recursos Naturais , Solo , Brasil , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Agricultura/métodos
2.
J Small Anim Pract ; 65(3): 176-180, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38185815

RESUMO

OBJECTIVES: This study aimed to assess the prevalence of blood-borne infectious agents in healthy, client-owned dogs from a blood donor population in Portugal and Spain, and to address the importance of a screening protocol on every donation. MATERIALS AND METHODS: Client-owned healthy dogs were tested before each donation on a veterinary blood bank. Blood samples from new potential donors, and from regular donors, were tested by real-time polymerase chain reaction for Leishmania species, Ehrlichia species, Brucella species, Babesia species and Anaplasma species Serological tests were also performed for Leishmania species, Ehrlichia species and Dirofilaria immitis. All donors were tested for every infectious agent in each donation. RESULTS: The study found that out of a total of 8036 donors and 35,120 samples tested, 3.9% of blood donors tested positive for at least one of the agents, with the most prevalent being Anaplasma species (2.1%). Serological tests also revealed positive results in 14.0% of donors, with the highest percentage for Leishmania species (7.7%). Moreover, the study found that 28.2% of positive results were from dogs with negative results in donations performed 3 to 12 months before, and 18.0% of positive results were recent infections. CLINICAL SIGNIFICANCE: These findings indicate a high prevalence of infectious agents in seemingly healthy, selected dogs eligible to become blood donors in the Iberian Peninsula, highlighting the importance of regular testing on every donation. This study emphasises the importance of a regular screening protocol for every donation instead of annual testing, as is commonly performed in veterinary medicine.


Assuntos
Doenças do Cão , Ehrlichiose , Humanos , Cães , Animais , Doadores de Sangue , Prevalência , Ehrlichia , Doenças do Cão/epidemiologia , Ehrlichiose/veterinária
3.
J Small Anim Pract ; 62(2): 107-113, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33305378

RESUMO

OBJECTIVES: This study aims to determine the prevalence of subclinical infectious agents considered core pathogens for worldwide screening in healthy, client-owned, indoor cats eligible to become blood donors in Spain and Portugal. MATERIALS AND METHODS: Blood samples of healthy, indoor, domestic cats selected to be potential blood donors were tested for feline leukaemia virus antigens, feline immunodeficiency virus antibodies and polymerase chain reactions for Mycoplasma haemofelis, Candidatus Mycoplasma haemominutum, Candidatus Mycoplasma turicensis, feline leukaemia virus provirus, Leishmania spp. and Bartonella spp. Not all donors were tested for all agents. RESULTS: Overall, 5105 healthy indoor cats were tested and 8.1% (414/5105) had at least one subclinical infectious agent that is transmissible through blood product transfusion. 1.5% (77/5105) were positive for feline leukaemia virus antigens and 2.9% (148/5105) were positive for feline immunodeficiency virus antibodies, therefore they were excluded as donors. The overall prevalence of haemoplasmas in feline leukaemia virus and feline immunodeficiency virus SNAP-negative feline blood donors was 3.7% (181/4880) [1.3% (63/4880) were positive for Mycoplasma haemofelis; 2.3% (112/4880) to Candidatus Mycoplasma haemominutum and 0.12% (6/4880) to Candidatus Mycoplasma turicensis]. The prevalence of feline leukaemia provirus was 5.2% (9/173) and of Bartonella spp. was 0.2% (2/1122). None of the 173 cats were positive for Leishmania spp. CLINICAL SIGNIFICANCE: The prevalence of many transfusion transmissible pathogens was relatively high in this healthy, client-owned, indoor cats eligible to become blood donors. Performing an extended screening panel that includes at least polymerase chain reactions for Mycoplasma haemofelis, Candidatus Mycoplasma haemominutum, Candidatus Mycoplasma turicensis, feline leukaemia virus provirus, and Bartonella spp., in addition to feline leukaemia virus antigens and feline immunodeficiency virus antibodies, is recommended in pet blood banks from analogous regions.


Assuntos
Bartonella , Doenças do Gato , Infecções por Mycoplasma , Mycoplasma , Animais , Doadores de Sangue , Gatos , Humanos , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/veterinária
4.
Int J Biol Macromol ; 165(Pt B): 1803-1812, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33075342

RESUMO

In the present research, soybean straw was used to prepare nanocellulose (NC) via a ball mill, in different milling times (6, 9, and 12 h) and in-situ modified with an anionic surfactant. NCs were characterized for their chemical structure, surface composition, dimension and stability, morphology, crystalline structure, and thermal stability. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy results indicated a cellulosic structure for NCs and a physical interaction due to the electronic attractions between nanocellulose hydroxyls and surfactant end chain groups. The dynamic light scattering, Zeta potential, and transmission electron microscopy indicated that the in situ modified samples showed smaller sizes and good electrostatic stability. Besides, while ball mill resulted in nanofibers, the in situ modified-NC showed a nanocrystal shape, indicating that the surfactant alters the milling process and cellulose scale reduction. The modified-NC showed lower crystallinity and crystal size than unmodified nanocelluloses due to the surfactant chains' addition and influence during the milling process. The modified-NC showed slightly superior thermal stability. The NC-12S showed smaller particle sizes, high electrostatic, and thermal stability and indicated that 12 h is adequate to prepare modified nanocellulose via in situ modification. The prepared samples could be potentially used as coatings, emulsifiers, and nanocomposites reinforcing agents.


Assuntos
Celulose/química , Nanocompostos/química , Resíduos , Tamanho da Partícula , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Temperatura , Termogravimetria , Difração de Raios X
5.
Environ Monit Assess ; 192(7): 434, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32542519

RESUMO

Soil erosion affects agricultural production by reducing the area of rural properties and altering the dynamics of watersheds. Gullies are a complex and irregular type of erosion form that can reach large dimensions, and studying gullies to stabilize erosion processes is a challenge. This study aims to understand their environmental relationships as a basis for future research and to recover land degraded by soil erosion. We combined mapping techniques using geographic information system (GIS) with temporal evolution of land use and fractal dimensions of gullies using FracLac to determine the stability of gullies in a watershed in south Minas Gerais (Brazil). We used R software to apply linear regressions and tested the statistics to verify the compatibility of the model. Environmental characteristics of the watershed contribute to the formation of gullies, but human activities influence the deflagration of these features. The temporal evolution of the land use demonstrated that nearly 50% of the watershed was used as pastures throughout the years, which contributed to soil degradation. The evolution of the fractal dimension showed fluctuations over the years, indicating that the gullies are not stable. The regressions suggest that the vegetation, geology, land use, channel order, and curvature may influence the fractal dimensions of gullies. We concluded that human activity influences the evolution of gullies; the use of techniques such as vegetation measures can contribute to the stabilization of gullies. We also concluded that fractal analysis is an interesting tool for performing environmental evaluations of irregular and complex features, such as gullies.


Assuntos
Conservação dos Recursos Naturais , Sistemas de Informação Geográfica , Brasil , Monitoramento Ambiental , Fractais , Solo
6.
Genet Mol Res ; 16(3)2017 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-28973745

RESUMO

The objective of this study was the identification of the cytoplasmic types and the genotyping for the fertility restoration nuclear locus (Ms) in 59 onion accessions, aiming at the selection of 'A' and 'B' lines essential for the obtainment of hybrids. Three markers were used to identify the cytoplasm 5' cob, orfA501, and orf725, and two were used for the Ms locus (AcSKP1 and AcPMS1). The two types of male-sterile cytoplasm ('S' and 'T'), as well as fertile cytoplasm ('N'), and the Ms and ms alleles in both homozygosity and heterozygosity were detected in the 59 genotypes evaluated in the experiment. The frequencies of the 5' cob/orfA501 and orf725 markers, as well as of the markers AcSKP1 and AcPMS1, were close in the onion accessions evaluated in this study. In the Brazilian germplasm, the frequencies of the 'N', 'S', and 'T' cytoplasm were approximately 0.47, 0.28, and 0.25, respectively, whereas the allele frequencies of Ms and ms were 0.52 and 0.48, respectively. The accessions Régia, EHCEB 20146, EHCEB 201427, Alvorada, Serrana, Crioula Mercosul, EHCEB 20142, BRS 367, Rainha, Juporanga, and Alfa SF C-XI have potential for the identification of 'A' and 'B' lines, since they presented mixtures of cytoplasm and different allele frequencies for Ms. All the plants of the accessions EHCEB 20142040/EHCEB 20141040, EHCEB 20142028/EHCEB 20141028, and EHCEB 20112006/EHCEB 20111006 were in the Nmsms and Smsms conditions, and have the potential for 'B' and 'A' lines, respectively, for the CMS-S system. All the plants of the accessions EHCEB 20142027/EHCEB 20141027, EHCEB 20102019/EHCEB 20101019, and Alfa SF 'B'/Alfa SF 'A' were in Nmsms and Tmsms conditions, and have the potential for 'B' and 'A' lines, respectively, for the CMS-T system.


Assuntos
Citoplasma/genética , Genes de Plantas , Cebolas/genética , Infertilidade das Plantas/genética , Loci Gênicos , Cebolas/fisiologia
7.
Arq. bras. med. vet. zootec ; 61(4): 825-834, ago. 2009. ilus
Artigo em Português | LILACS | ID: lil-524436

RESUMO

Compararam-se duas técnicas cirúrgicas de redução e estabilização da articulação coxofemoral experimentalmente luxada em cães. Dois grupos de animais, submetidos às respectivas técnicas após a indução cirúrgica da luxação, foram acompanhados clínica e radiograficamente por um período de 60 dias, findos os quais, realizaram-se avaliações macroscópica e histológica e teste de tensiometria das articulações. Cada grupo foi constituído por oito animais, clinicamente sadios, com pesos entre 5 e 20kg. Os animais submetidos ao implante de fáscia apresentaram, ao exame físico, evolução da deambulação significativamente precoce em relação aos do grupo submetido ao implante de pino de Steinmann, além de menor grau de atrofia muscular. Os testes de tensiometria, as avaliações macroscópicas e radiográficas e os exames histológicos não diferiram entre os grupos, evidenciando também que ambas as técnicas não geraram alterações deletérias à articulação operada. Conclui-se que a técnica de estabilização da articulação coxofemoral com implante de fascia lata foi clinicamente eficaz e vantajosa quando comparada à técnica do pino transarticular.


It was compared both surgical techniques of reduction and stabilization of experimentally luxated coxofemoral join in dog. Two groups were submitted to the techniques after surgical induction of the luxation. All animals were clinically and radiografically observed during 60 days. After that, a macroscopic study, an histological exam, and a tensiometry test in the articulations were performed. Each group had eight healthy animals, weighting from 5 to 20kg. The most important advantage was related to the deambulation, which the animals submited to the facia lata implant showed a faster evolution after the surgery at the physical exam, and muscular atrophy in a smaller degree. The tensiometry tests, the radiographic and the histological exams did not present important differences between both groups, but they were useful to show that the two techniques did not cause alterations in the studied articulation. It can be concluded that the stabilization of the coxofemoral articulation using bubaline fascia lata implant was clinically efficient and more advantageous compared to the transarticular pin technique.

8.
Braz J Med Biol Res ; 38(7): 985-94, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16007270

RESUMO

The essential amino acids lysine and threonine are synthesized in higher plants via a pathway starting with aspartate that also leads to the formation of methionine and isoleucine. Lysine is one of most limiting amino acids in plants consumed by humans and livestock. Recent genetic, molecular, and biochemical evidence suggests that lysine synthesis and catabolism are regulated by complex mechanisms. Early kinetic studies utilizing mutants and transgenic plants that over-accumulate lysine have indicated that the major step for the regulation of lysine biosynthesis is at the enzyme dihydrodipicolinate synthase. Despite this tight regulation, recent strong evidence indicates that lysine catabolism is also subject to control, particularly in cereal seeds. The challenge of producing crops with a high-lysine concentration in the seeds appeared to be in sight a few years ago. However, apart from the quality protein maize lines currently commercially available, the release of high-lysine crops has not yet occurred. We are left with the question, is the production of high-lysine crops still a challenge?


Assuntos
Produtos Agrícolas/metabolismo , Lisina/biossíntese , Treonina/biossíntese , Grão Comestível/metabolismo , Humanos , Plantas Geneticamente Modificadas/metabolismo
9.
Braz. j. med. biol. res ; 38(7)July 2005. ilus
Artigo em Inglês | LILACS | ID: lil-403854

RESUMO

The essential amino acids lysine and threonine are synthesized in higher plants via a pathway starting with aspartate that also leads to the formation of methionine and isoleucine. Lysine is one of most limiting amino acids in plants consumed by humans and livestock. Recent genetic, molecular, and biochemical evidence suggests that lysine synthesis and catabolism are regulated by complex mechanisms. Early kinetic studies utilizing mutants and transgenic plants that over-accumulate lysine have indicated that the major step for the regulation of lysine biosynthesis is at the enzyme dihydrodipicolinate synthase. Despite this tight regulation, recent strong evidence indicates that lysine catabolism is also subject to control, particularly in cereal seeds. The challenge of producing crops with a high-lysine concentration in the seeds appeared to be in sight a few years ago. However, apart from the quality protein maize lines currently commercially available, the release of high-lysine crops has not yet occurred. We are left with the question, is the production of high-lysine crops still a challenge?.


Assuntos
Humanos , Produtos Agrícolas/metabolismo , Lisina/biossíntese , Treonina/biossíntese , Grão Comestível/metabolismo , Plantas Geneticamente Modificadas/metabolismo
10.
Pharmacol Res ; 41(3): 291-7, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10675280

RESUMO

We studied here the effect of a wide range of adenosine concentration and time of preincubation, on the histamine release induced in the guinea pig mast cells by different stimulus. Adenosine (10(-5)-10(-3)m) potentiated the histamine release induced by antigen in the guinea pig heart (isolated and dispersed tissue) and lung mast cells but not induced by ionophore A23197. The potentiation caused by adenosine (10(-4)m) was maximum after 1-3 min of preincubation and is probably an extracellular effect since it was not avoided by dipyridamol (3x10(-7)-10(-6)m) that inhibit the uptake of adenosine. Similar potentiation was also produced by the adenosine mimetic 2-chloroadenosine (10(-5)m) and both effects were inhibited by 8-phenyltheophylline indicating an effect on the type A receptors. It is suggested that the adenosine potentiation may not be related to changes on the cyclic AMP levels. 2000 Academic Press@p$hr


Assuntos
Adenosina/farmacologia , Liberação de Histamina/efeitos dos fármacos , Mastócitos/efeitos dos fármacos , 2-Cloroadenosina/farmacologia , Animais , Bucladesina/metabolismo , Dipiridamol/farmacologia , Interações Medicamentosas , Feminino , Cobaias , Pulmão/citologia , Pulmão/metabolismo , Masculino , Mastócitos/metabolismo , Miocárdio/citologia , Miocárdio/metabolismo , Teofilina/análogos & derivados , Teofilina/farmacologia , Fatores de Tempo , Vasodilatadores/farmacologia
11.
Arq Neuropsiquiatr ; 55(3B): 650-8, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9629422

RESUMO

The usual approach to language disorders relies on standardised evaluations in which pattern-tests characterise the subject's status according to the classical aphasiological typology. Those data are then analysed to support a traditional prevalent criterion for the distinction between "normal" and "pathological" linguistic performance, which is strictly focused on a quantitative approach. In the present study a method for evaluation and treatment of aphasia is proposed in which socio-cultural conditions are emphasised, in order to expand this conventional criterion as to encompass a qualitative (individualised) one. Although the methodology draws the attention, the results here obtained also point to the importance of re-evaluating what is presently considered as the most appropriate criterion for "normal" cognitive processes, particularly those related to language.


Assuntos
Afasia de Condução/diagnóstico , Afasia de Condução/terapia , Individualidade , Afasia de Condução/psicologia , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
12.
Inflamm Res ; 45(9): 442-7, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8891754

RESUMO

We have characterized the histamine releasing effects of lectins extracted from Brazilian beans, in comparison to concanavalin A, in hamster cheek pouch cell suspensions containing mast cells. The lectins from Dioclea virgata, Canavalia brasiliensis, and Dioclea rostrata induce histamine release in a similar manner to concanavalin A, but appear to differ in potency and efficacy. The effects depended on the temperature, pH, and metabolic energy, demonstrating the non-cytotoxic nature of the histamine release. It is suggested that the lectins studied act by the same mechanism as concanavalin A (interacting with sugars in the antibodies bound to the mast cells), since high concentrations of glucose inhibit the histamine release. The lectins at high concentrations quench the histamine release. This suppression is reversed by increasing calcium concentration, suggesting that the lectins bind to the calcium that is essential for the secretion, thereby confirming and extending our previous data using the lectin from Dioclea virgata in rat peritoneal mast cells.


Assuntos
Liberação de Histamina/efeitos dos fármacos , Lectinas/farmacologia , Mastócitos/metabolismo , Mucosa Bucal/metabolismo , Animais , Bochecha , Concanavalina A/farmacologia , Cricetinae , Feminino , Concentração de Íons de Hidrogênio , Masculino , Fosfatidilserinas/farmacologia , Temperatura
13.
Agents Actions ; 41(3-4): 132-5, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-7524287

RESUMO

The histamine releasing properties of glucose (mannose)-specific lectins isolated from Brazilian beans was examined. The Canavalia brasiliensis, Dioclea rostrata, and Dioclea virgata lectins induced histamine release in rat peritoneal mast cells similar to concanavalin A. Less potency and efficacy was observed for Canavalia maritima, Dioclea guianensis, and Dioclea violacea while very low activities were seen for the lectins from Dioclea grandiflora, Canavalia bonariensis, and Cratylia floribunda. The histamine releasing effect was quenched by higher doses of D. virgata lectin similar to what was reported for concanavalin A. This effect was abrogated by increasing the concentration of calcium in the incubating medium. As these above proteins have sites that bind calcium, higher doses of the lectins might withdraw the calcium which is essential for the mast cell secretion.


Assuntos
Concanavalina A/farmacologia , Liberação de Histamina/efeitos dos fármacos , Lectinas/farmacologia , Mastócitos/efeitos dos fármacos , Animais , Cálcio/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Fabaceae/química , Lectinas/isolamento & purificação , Cavidade Peritoneal/citologia , Lectinas de Plantas , Plantas Medicinais , Ratos , Ratos Wistar
15.
Rev. saúde pública ; 15(3): 251-62, 1981.
Artigo em Português | LILACS | ID: lil-2697

RESUMO

Estudo epidemiologico de 341 acidentes de trabalho fatais ocorridos em Campinas, no periodo do 1972 a 1978, realizado a partir da consulta a arquivos do Instituto Nacional de Previdencia Social (INPS). Identificaram-se como caracteres epidemiologicos predominantes o acometimento de adultos jovens (68,3% das vitimas fatais tinham menos de 40 anos), do sexo masculino (95,6%); os condutores de veiculos de transporte constituiram a categoria profissional mais acometida (19,4%), em seguida da dos serventes de obras (10,4%); a construcao civil foi o ramo de atividade que mais contribuiu para a mortalidade por acidentes de trabalho (29,9%); os acidentes de transito de veiculos a motor constituiram-se na causa externa mais frequente (50,1%), seguindo-se o grupo dos outros acidentes(22,9%) e o das quedas acidentais (12,6%); os traumatismos de cranio foram a natureza da lesao mais frequente. Sao mencionados alguns aspectos a serem considerados na prevencao, quanto a prioridade da construcao civil e quanto a participacao das Empresas na prevencao de acidentes de transito em situacao ocupaciona


Assuntos
Acidentes de Trabalho , Brasil
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