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1.
Braz J Biol ; 83: e270865, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37222368

RESUMO

The present study aimed to evaluate concentrations and forms of application of salicylic acid used for water stress mitigation on the gas exchange and growth of yellow passion fruit. The experimental design was arranged in randomized blocks in a 4 × 4 × 2 factorial scheme, with four concentrations of salicylic acid (SA) via foliar application (0.0, 0.7, 1.4, and 2.1 mM), four SA concentrations via fertigation (0.0, 0.7, 1.4, and 2.1 mM), and two irrigation depths estimated based on the actual evapotranspiration - ETr (50 and 100% of ETr), with three replications. Water stress negatively affected the physiology and growth of yellow passion fruit seedlings at 75 days after sowing (DAS). The application of salicylic acid, regardless of the form of application, attenuates the effects of water stress on gas exchange and growth of yellow passion fruit, with the best results obtained when applying a concentration of 1.30 mM via leaf or 0.90 mM via fertirrigation. The combination of foliar application of AS and fertigation contributed to improve photosynthetic and growth parameters under water conditions of 50 and 100% of ETr. The foliar application of AS presents superior responses to the application via fertigation. These results reinforce the hypothesis that the attenuation of water stress by salicylic acid is related to the maintenance of gas exchange, which depends on the concentration and form of application, and studies testing combinations throughout the crop cycle become promising for advances in knowledge from the action of this phytohormone on abiotic stress.


Assuntos
Passiflora , Desidratação , Frutas , Plântula , Ácido Salicílico
2.
Braz J Biol ; 82: e265069, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36327399

RESUMO

Salt stress caused by excess salts present in irrigation water, is one of the biggest barriers in agricultural production, especially in semi-arid regions. Thus, the use of substances, such as salicylic acid, that minimize the deleterious effects of salinity on plants can be an alternative to ensure satisfactory production. In this context, the objective of this study was to evaluate the effects of different methods of application of salicylic acid on the growth, production and water use efficiency of cherry tomato plants under salt stress. The study was conducted in a greenhouse, using an Entisol soil with a sandy loam texture. The treatments were distributed in a completely randomized design, in a 2×4 factorial arrangement, corresponding to two levels of electrical conductivity of irrigation water - ECw (0.6 and 2.6 dS m-1) and four methods of application of salicylic acid (Control - without application of SA; via spraying; via irrigation and via spraying and irrigation), with five replicates and one plant per plot. The salicylic acid concentration used in the different methods was 1.0 mM. Application of salicylic acid via foliar spraying increased the growth, production and water use efficiency of cherry tomato plants. The salt stress induced by the electrical conductivity of 2.6 dS m-1 was attenuated by the foliar application of salicylic acid. The use of water of 2.6 dS m-1 associated with the application of salicylic acid via irrigation water further intensified the adverse effects of salinity on cherry tomato plants.


Assuntos
Solanum lycopersicum , Ácido Salicílico/farmacologia , Salinidade , Estresse Salino , Água
3.
Environ Entomol ; 46(4): 995-1004, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28881958

RESUMO

Biological features of Diaeretiella rapae (McIntosh), an aphid parasitoid, are conditioned by temperature and host. However, studies of host quality changes due to temperature adaptability have not been performed previously. Therefore, this study evaluated the adaptability of Lipaphis pseudobrassicae (Davis) and Myzus persicae (Sulzer) to high temperature, high temperature effect on their quality as hosts for D. rapae, and on parasitoid's thermal threshold. Aphid development, survivorship, fecundity, and longevity were compared at 19 °C and 28 °C. Host quality in different temperatures was determined through evaluation of parasitoid biology. Thermal threshold of D. rapae was determined using development time data. At 28 °C, development time, rate of immature survival, and total fecundity rates were greater in L. pseudobrassicae than in M. persicae. Development time of D. rapae in L. pseudobrassicae was shorter than that in M. persicae at 28 °C and 31 °C for females and at 31 °C for males. The thermal threshold of D. rapae was 6.38 °C and 3.33 °C for females and 4.45 °C and 3.63 °C for males developed on L. pseudobrassicae and M. persicae, respectively. Diaeretiella rapae size gain was greater in L. pseudobrassicae than that in M. persicae at 25 °C and 28 °C. Lipaphis pseudobrassicae showed better adaptation than M. persicae to elevated temperatures, which resulted in a better quality host for D. rapae at temperatures of 28 °C and 31 °C and a higher lower thermal threshold when the parasitoid developed within L. pseudobrassicae. The host's adaptation to high temperatures is a determinant of host quality for the parasitoid at that same climatic condition.


Assuntos
Afídeos/fisiologia , Afídeos/parasitologia , Interações Hospedeiro-Parasita , Himenópteros/fisiologia , Adaptação Fisiológica , Animais , Afídeos/crescimento & desenvolvimento , Feminino , Himenópteros/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/parasitologia , Larva/fisiologia , Masculino , Temperatura
5.
Arq. bras. med. vet. zootec ; 66(5): 1611-1614, Sep-Oct/2014. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1095994

RESUMO

From fifteen female dogs with clinical diagnoses of pyometra, hematological exams were performed at three times: M0 (prior to the surgery), M24 (24h after ovarysalpingohisterectomy-OSH) and M48 (48h after OSH). Anemia was seen in 80% of the cases, characterized as mild normocytic normochromic type. The means of total leukocyte counts were 27.043, 57.940 and 40.139 céls/µL in M0, M24 and M48. A total of80% of the animals presented neutrophilic left shift in all moments. During medullar exams, the cellular, iron reserve and megakaryocytic concentration were raised as well as the ME ratio, showing a value of 26,3:1,0, probably due to the elevation of granular proliferation and maturation compartment, as the mean of the reserve compartment was within normal range. As 83% of the animals with neutrophilic left shift showed a melullary reserve compartment raised, it can be concluded that female dogs with piometra had left shift of neutrophils with disproportionally between compartments, without segmented medullar saturation.(AU)


Assuntos
Animais , Feminino , Cães , Medula Óssea/patologia , Piometra/veterinária , Neutrófilos , Contagem de Células Sanguíneas/veterinária
6.
J Chemother ; 23(3): 135-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21742581

RESUMO

The aim of this study was to identify phenotypic changes in a laboratory-derived strain of ertapenem-resistant Escherichia coli (Ec-ERT) when compared to its susceptible parent strain (Ec-WT). In both strains, we assessed both the effects of ertapenem via time-kill curves and the occurrence of cross resistance with other beta-lactams. The strains were compared based on growth pattern, biochemical-physiological profile and changes in the subproteome using 2D-DIGE followed by MALDI-TOF/TOF MS. To assess virulence, we employed a murine model of intraperitoneal infection in which we investigated the invasiveness of both strains. Growth persistence of the laboratory-derived resistant strain was observed via the time-kill curve assay, but cross resistance was not observed for other beta-lactams. We also observed a slower growth rate and changes in the biochemical and physiological characteristics of the drug-resistant bacteria. In the resistant strain, a total of 51 protein spots were increased in abundance relative to the wild-type strain, including an outer membrane protein A, which is related to bacterial virulence. The mouse infection assay showed a higher invasiveness of the Ec-ERT strain in relation to the Ec-WT strain. In conclusion, the alterations driven by ertapenem in E. coli reinforce the idea that antimicrobial agents may interfere in several aspects of bacterial cell biology, with possible implications for host-bacteria interactions.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , beta-Lactamas/farmacologia , Animais , Proteínas da Membrana Bacteriana Externa/metabolismo , Farmacorresistência Bacteriana , Ertapenem , Escherichia coli/metabolismo , Escherichia coli/patogenicidade , Camundongos , Testes de Sensibilidade Microbiana , Fenótipo , Eletroforese em Gel Diferencial Bidimensional , Virulência , beta-Lactamas/metabolismo
7.
Arq. bras. med. vet. zootec ; 63(2): 499-502, abr. 2011. tab
Artigo em Português | LILACS | ID: lil-591146

RESUMO

The possible changes in the bone marrow associated with hematological changes in peripheral blood during the first six weeks of life in cattle were evaluated. To this purpose, blood samples were evaluated at 2, 4, 7, 10, 14, 21, 28, 35, and 42 days of life, and cytologic examination of bone marrow at 2, 7, 21, and 42 days of life in 10 Holstein calves. The bone marrow examination showed, in different times, myeloid:erythroid ratio from 0.60 to 0.69. The erythroid lineage distribution remained pyramidal, with concentration of precursor cells above the initial reference values for adult cattle. Proliferation pool of myeloid lineage also remained above the reference range, with decreases of concentrations in the third and sixth weeks. In the lymphoid lineage, the concentration of lymphocytes showed a decrease in the first three weeks, with a tendency to rise in the sixth week.


Assuntos
Animais , Biologia Celular/tendências , Bovinos/classificação , Hematologia/tendências , Colostro , Medula Óssea/anatomia & histologia
8.
Lett Appl Microbiol ; 49(6): 738-44, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19780950

RESUMO

AIMS: To compare the effects of five yeast probiotic formulations on viability, revival and washout kinetic in the digestive tract of mice, and the protection against an experimental infection with Salmonella enterica serovar Typhimurium. METHODS AND RESULTS: The number of viable cells in five commercial probiotic products codified as A, B, C and D (Saccharomyces boulardii- lyophilized) and E (Saccharomyces cerevisiae- aqueous suspension) was determined, as well as revival and washout kinetic in mouse intestine. Protective capacity was evaluated by survival rate and histopathology of liver and intestine of mice treated with each product and then challenged with Salm. Typhimurium. CONCLUSIONS: Product A contained the highest number of viable cells and, fed to mice, gave the highest counts of viable yeasts and the longest persistence in faeces. Probably as a consequence, the highest survival and protection of intestinal and hepatic tissues were observed when product A was used for mouse treatment. Product E showed low counts in the formulation and was not recovered from mouse intestine. SIGNIFICANCE AND IMPACT OF THE STUDY: Formulation (lyophilization or aqueous suspension) is an important factor for revival and survival of a probiotic product in vivo and consequently for its protective properties.


Assuntos
Probióticos/administração & dosagem , Probióticos/farmacologia , Saccharomyces , Salmonelose Animal/prevenção & controle , Animais , Contagem de Colônia Microbiana , Fezes/microbiologia , Intestinos/microbiologia , Intestinos/patologia , Fígado/patologia , Camundongos , Salmonelose Animal/patologia , Salmonella typhimurium
9.
Transpl Infect Dis ; 11(2): 132-6, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18983416

RESUMO

Strongyloides stercoralis is an intestinal nematode that causes human infections and whose life cycle has special features, including autoinfection. Strongyloides infection may be asymptomatic for years, owing to a low parasite load. During immunosuppressive therapy, however, if cellular immunity is depressed, autoinfection can occur at a higher rate, resulting in hyperinfection syndrome. In this specific circumstance, it can become a fatal illness. We describe a case of hyperinfection syndrome in a liver transplant recipient and also review the literature.


Assuntos
Imunossupressores/efeitos adversos , Transplante de Fígado/efeitos adversos , Complicações Pós-Operatórias/parasitologia , Strongyloides stercoralis , Estrongiloidíase/etiologia , Superinfecção/etiologia , Adulto , Animais , Anti-Helmínticos/uso terapêutico , Evolução Fatal , Rejeição de Enxerto/prevenção & controle , Humanos , Imunossupressores/uso terapêutico , Masculino , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/tratamento farmacológico , Recidiva , Estrongiloidíase/diagnóstico , Estrongiloidíase/tratamento farmacológico , Superinfecção/diagnóstico , Superinfecção/tratamento farmacológico
11.
Rev Med Chil ; 122(1): 82-7, 1994 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-8066349

RESUMO

This is a clinico-pathological report of a 30 years old male patient that presented with acute epigastric pain. Ultrasound examination showed a retroperitoneal tumor, thrombosis of the inferior vena cava and ascites. CAT scan disclosed thrombosis of hepatic vein and inferior vena cava with right atrium involvement. Necropsy showed a leiomyosarcoma of the inferior vena cava. There are seldom reports of this tumor in the last 5 years and an early diagnosis allows therapeutic interventions associating surgery, radiotherapy and chemotherapy.


Assuntos
Leiomiossarcoma/patologia , Veia Cava Inferior , Adulto , Biópsia , Diagnóstico Diferencial , Humanos , Leiomiossarcoma/diagnóstico , Masculino , Tomografia Computadorizada por Raios X , Doenças Vasculares/patologia
12.
Arq Bras Cardiol ; 60(4): 243-5, 1993 Apr.
Artigo em Português | MEDLINE | ID: mdl-8311732

RESUMO

PURPOSE: To evaluate the role of arterial hypertension (AH) in the development of proteinuria in patients with decompensated congestive heart failure (CHF). METHODS: Twenty-four-hour urinary protein determinations were obtained from 30 patients with decompensated CHF, before and after therapy of CHF. The patients were divided in two groups according with the presence of AH as cause of CHF: group A, 18 patients with CHF due to AH and group B, 12 patients with CHF due to idiopathic dilated or chagasic cardiomyopathy without previous AH. RESULTS: There was no differences between the groups concerning age, sex, renal function and duration of CHF. Before treatment, 88% of group A presented proteinuria exceeding 150 mg/24h compared to 25% of group B (p < 0.01). After treatment of CHF, proteinuria > 150 mg/24 h remained in 38% of group A and in none of group B. Proteinuria did not reverse after 6 months of follow-up in 2 patients, one of them showed benign nephrosclerosis in renal biopsy. CONCLUSION: Patients with decompensated CHF, unrelated to AH, presented mild proteinuria reversible after the treatment, that improved renal function. In patients with CHF due to AH, proteinuria was more frequent, more severe and did not improve after the treatment, suggesting renal lesion.


Assuntos
Insuficiência Cardíaca/complicações , Hipertensão/etiologia , Proteinúria/etiologia , Creatinina/urina , Feminino , Insuficiência Cardíaca/urina , Humanos , Hipertensão/urina , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteinúria/urina
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