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8.
Braz J Microbiol ; 55(2): 1451-1463, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38656427

RESUMO

Antarctic temperature variations and long periods of freezing shaped the evolution of microorganisms with unique survival mechanisms. These resilient organisms exhibit several adaptations for life in extreme cold. In such ecosystems, microorganisms endure the absence of liquid water and exhibit resistance to freezing by producing water-binding molecules such as antifreeze proteins (AFP). AFPs modify the ice structure, lower the freezing point, and inhibit recrystallization. The objective of this study was to select and identify microorganisms isolated from different Antarctic ecosystems based on their resistance to temperatures below 0 °C. Furthermore, the study sought to characterize these microorganisms regarding their potential antifreeze adaptive mechanisms. Samples of soil, moss, permafrost, and marine sediment were collected on King George Island, located in the South Shetland archipelago, Antarctica. Bacteria and yeasts were isolated and subjected to freezing-resistance and ice recrystallization inhibition (IR) tests. A total of 215 microorganisms were isolated, out of which 118 were molecularly identified through molecular analysis using the 16S rRNA and ITS regions. Furthermore, our study identified 24 freezing-resistant isolates, including two yeasts and 22 bacteria. A total of 131 protein extracts were subjected to the IR test, revealing 14 isolates positive for AFP production. Finally, four isolates showed both freeze-resistance and IR activity (Arthrobacter sp. BGS04, Pseudomonas sp. BGS05, Cryobacterium sp. P64, and Acinetobacter sp. M1_25C). This study emphasizes the diversity of Antarctic microorganisms with the ability to tolerate freezing conditions. These microorganisms warrant further investigation to conduct a comprehensive analysis of their antifreeze capabilities, with the goal of exploring their potential for future biotechnological applications.


Assuntos
Proteínas Anticongelantes , Bactérias , Congelamento , Regiões Antárticas , Proteínas Anticongelantes/metabolismo , Proteínas Anticongelantes/química , Proteínas Anticongelantes/genética , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Bactérias/isolamento & purificação , Ilhas , Filogenia , Leveduras/genética , Leveduras/classificação , Leveduras/isolamento & purificação , Leveduras/metabolismo , RNA Ribossômico 16S/genética , Ecossistema
9.
Braz J Biol ; 84: e273999, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38451628

RESUMO

The production of seedlings of the passion fruit tree, usually, is sexual, and the seeds are not uniform in the seedling emergence, and soaking treatments of seeds can provide faster and more uniform germination. It was aimed to study the action of plant growth regulators and the mobilization of reserves in the stages of soaking of yellow passion fruit seeds. The seeds were soaked for five hours in solutions containing plant growth regulators, in a completely randomized design, in a factorial 8 x 4, with four replications. The first factor corresponds to eight plant growth regulators: T1 - distilled water (control); T2 - 6-benzylaminepurine ​​500 mg L-1; T3 - 4-(3-indolyl) butyric acid 500 mg L-1; T4 - gibberellic acid 500 mg L-1; T5 - spermine 250 mg L-1; T6 - spermine 750 mg L-1; T7 - spermidine 750 mg L-1; T8 - spermidine 1250 mg L-1; and the second factor, to the four soaking times: zero, four, 72 and 120 hours, corresponding, respectively, to the dry seed, and to phases I, II, and III of the imbibition curve. It was evaluated the biochemical composition of seeds (lipids, soluble sugars and starch). The seeds showed accumulation of lipids in phase III; the content of soluble sugars increased in phase I and decreased in phase II. The starch content increased until the phase II and decreased in phase III. Starch is the main reserve in the seeds and the main source of energy used in phase III; soaking the seeds in polyamines generates an accumulation of lipids in the seeds and soaking in plant growth regulators increases the burning of starch.


Assuntos
Passiflora , Reguladores de Crescimento de Plantas , Reguladores de Crescimento de Plantas/farmacologia , Frutas , Espermidina , Espermina , Ácido Butírico , Plântula , Amido , Açúcares
10.
Braz J Biol ; 83: e277437, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422256

RESUMO

The use of residues from coffee production to obtain biochar is a sustainable approach, which aims to minimize the environmental impact of these materials. In this study, the effect of adding coffee straw biochar on the physiological quality of lettuce and sorghum seeds was investigated. Thus, the objective of this work was to study the effect of adding different concentrations of coffee biochar in the substrate composition on the physiological quality of lettuce (Lactuca sativa) and sorghum (Sorghum bicolor) seeds. The experimental design used was completely randomized, with five concentrations of biochar (0; 7.5; 15; 30 and 60%), conducted with four replications of 25 seeds. The use of biochar in the concentrations studied does not provide an increase in the average germination percentage and vigor of lettuce and sorghum seeds. The increase in the concentration of biochar caused less seed vigor, suggesting a toxic effect. For seed germination, there was no significant difference between lettuce and sorghum species, regardless of treatment. For the germination speed index, sorghum seeds have higher means, except for the treatment with the addition of 15% coffee straw biochar. Lettuce seeds have higher shoot length averages, except for treatment with 100% commercial substrate. The sorghum seeds have higher mean root length and dry mass than lettuce, regardless of the treatment.


Assuntos
Carvão Vegetal , Germinação , Sorghum , Café , Grão Comestível , Lactuca , Sementes/fisiologia
11.
Braz J Biol ; 83: e274888, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38055577

RESUMO

Ateleia glazioveana Baill. is a pioneer, rustic and can be used for forest recovery. This work aimed to study the process of physiological maturation of this species. The research was carried out in the city of Alegre - ES, the trees were identified in the floral anthesis and accompanied during the filling of the fruits and development of the seeds until the complete maturation. The fruits were harvested at the following stages 7, 14, 21, 28, 35 and 42 days after anthesis, and characterized according to: morphometry, moisture, fresh and dry mass of fruits and seeds, germination, germination speed index, shoot and root length and dry mass of seedlings. The regression equations were adjusted for the main characteristics analyzed as a function of the harvest period. The point of physiological maturity of timbó occurred at 42 days after anthesis.


Assuntos
Fabaceae , Sementes , Germinação/fisiologia , Plântula , Frutas
12.
Braz J Biol ; 83: e275338, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37970903

RESUMO

Simultaneous analysis studies of several agronomic traits in cultivated plants make it possible to identify phenotypic and genotypic differences due to environmental variations, such as altitude. Therefore, the objective was to evaluate, through multivariate analysis of agronomic, physicochemical and physiological characters, passion fruit hybrids cultivated in different environments. The hybrids used were Gigante Amarelo, Rubi do Cerrado and Sol do Cerrado, cultivated in the southern region of Espírito Santo in four municipalities/environments: Marataízes (41 m), Jerônimo Monteiro (104 m), Alegre (711 m), and Ibitirama (1016 m). The agronomic characters of the plants, the physical-chemical characteristics of the fruits and the physical, biochemical and physiological qualities of the seeds were analyzed. The Singh method was used to determine the most important differentiating characters between hybrids growing in different environments. Based on these characters, a dissimilarity matrix was generated and a principal coordinate analysis was performed. It was observed that the pulp yield was influenced by altitude. The three hybrids showed greater performance in terms of agronomic characters at altitude (41 m) than at altitude (104 m). The Sol do Cerrado hybrid showed high performance in the physical-chemical characteristics of the fruits at altitude (104 m).


Assuntos
Frutas , Passiflora , Frutas/genética , Passiflora/genética , Sementes , Agricultura , Análise Multivariada
13.
Public Health Pract (Oxf) ; 6: 100419, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37608848

RESUMO

Objective: Assess the perceived protection afforded by a range of COVID-19 vaccines in immune-mediated inflammatory diseases patients previously vaccinated against SARS-CoV-2. Study design: Survey. Methods: On-line cross-sectional survey aimed at evaluating the perceived protection (and its determinants) afforded by a range of COVID-19 vaccines among immune-mediated inflammatory diseases previously vaccinated for COVID-19. Results: Out of 493 eligible respondents who lived in Brazil, 397 (80.5%) were confident that their primary vaccination series would protect them against severe COVID-19. In multivariate analysis, only overlapping immune-mediated inflammatory diseases remained (negatively) associated with the perception of protection. Conclusions: No influence was found between COVID-19 vaccine types and the perception of protection after initial vaccinations.

14.
Immunol Lett ; 262: 7-17, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37634711

RESUMO

This study was designed to characterize mice bone marrow (BM) and bone marrow-derived dendritic cells (BMDC) and to compare the surface markers expression and inflammatory cytokine liberation in response to LPS and Bothrops jararacussu venom (BjV) stimulation. Typical morphology was observed in BM and BMDCs from the 4th up to the 8th day of culture using recombinant mouse GM-CSF and IL-4. A high basal level of MHC-II, CD1d, CD83, CD11c, CD80, and low CD86 was expressed by BM cells. After stimulation with GM-CSF/IL-4 for BMDCs differentiation, the BM cells differentiated into BMDCs presented MHC-II, CD1d, CD83, CD11c, CD86, and CD80 expression on the 4th - 8th day accompanied with high levels of TNF-α liberated. The difference between the surface markers' expression was observed in this time course in which CD1d, CD11c, and CD80 remained in high levels of expression, while MHC-II and CD83 showed moderate expression during the differentiation period. Also, cytokines liberation was monitored over the period of the BMDCs culture, and on the 6th day, low levels of IL-6 and IL-1ß were found, while high levels of TNF-α on the 4th and 8th days, both of which contributed to the maturity of the BMDCs. Maturation of DCs with LPS showed significant upregulation of surface markers (MHC-II, CD1d, CD83, CD86, CD80) and pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α) liberation. On the other hand, BjV induced a decrease in CD1d, CD11c, CD83, and CD86 expression in mature BMDCs which was not observed when LPS was used to stimulate BMDCs which probably induces impairment in T-cell activation.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos , Fator de Necrose Tumoral alfa , Animais , Camundongos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Medula Óssea , Interleucina-4 , Interleucina-6 , Lipopolissacarídeos , Venenos de Serpentes , Citocinas , Células Dendríticas
16.
J Phys Condens Matter ; 34(26)2022 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-35390772

RESUMO

Ordered mesoporous silica (OMS) was proved to be an efficient oral adjuvant capable to deliver a wide in size variety of different antigens, promoting efficient immunogenicity. This material can be used in single or polivalent vaccines, which have been developed by a group of Brazilian scientists. The experiments performed with the model protein Bovine Serum Albumin (BSA) gave the first promissing results, that were also achieved by testing the virus like particle surface antigen of hepatitis B (HBsAg) and diphtheria anatoxin (dANA). Nanostructured OMS, SBA-15 type, with bi-dimensional hexagonal porous symmetry was used to encapsulate the antigens either in the mesoporous (pore diameter ∼ 10 nm) or macroporous (pore diameter > 50 nm) regions. This silica vehicle proved to be capable to create an inflammatory response, did not exhibit toxicity, being effective to induce immunity in high and low responder mice towards antibody production. The silica particles are in the range of micrometer size, leaving no trace in mice organs due to its easy expulsion by faeces. The methods of physics, usually employed to characterize the structure, composition and morphology of materials are of fundamental importance to develop proper oral vaccines in order to state the ideal antigen load to avoid clustering and to determine the rate of antigen release in different media mimicking body fluids.


Assuntos
Dióxido de Silício , Vacinas , Adjuvantes Imunológicos , Animais , Antígenos , Antígenos de Superfície da Hepatite B , Camundongos , Porosidade , Dióxido de Silício/química
17.
Arq. bras. med. vet. zootec. (Online) ; 74(6): 1024-1038, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1416136

RESUMO

Ozone therapy is a technique used in several specialties of equine medicine; however, there are few studies on its use in vaquejada (cowboy competition) athlete horses. This study aims to evaluate the potential effect of ozone gas administered by two different routes on hematological and biochemical values and the oxidative stress marker in vaquejada athlete horses. For this, nine healthy equines that followed a training protocol and underwent two treatments were used with an 8-day wash-out between them. The major ozonated autohemotherapy (MOA) treatment group received a volume of 600ml of the 02-03 mixture at a concentration of 60 µg/mL, and the rectal insufflation (RI) treatment group received 5mL of gas per kg of body weight at a concentration of 15µg/kg performed every 24h on three consecutive days. Results were significant for RBC, hematocrit, and hemoglobin in the hematological variables, and AST and lactate for biochemical and malondialdehyde variables. No statistically significant differences were found in comparisons between treatment groups. Thus, we can conclude that there is no difference between the two therapies, indicating that the two techniques are effective for the application of ozone therapy in horses competing for vaquejada.


A ozonioterapia é uma técnica utilizada em diversas especialidades da medicina equina, contudo, são escassos os estudos de sua utilização em cavalos atletas de vaquejada. O presente estudo tem por objetivo avaliar o potencial efeito do gás ozônio administrado por duas diferentes vias sobre os valores hematológicos, bioquímicos e no marcador de estresse oxidativo em cavalos atletas de vaquejada. Para isso, foram utilizados 9 equinos hígidos que seguiram um protocolo de treinamento e foram submetidos a dois tratamentos, com um wash-out de 8 dias entre eles. O grupo de tratamento auto-hemoterapia maior ozonizada (AHTMO) recebeu um volume de 600ml da mistura 02-03 na concentração de 60 µg/mL e o grupo de tratamento insuflação retal (IR) recebeu 5mL de gás por kg de peso vivo, na concentração de 15µg/kg, realizado a cada 24h em três dias consecutivos. Os resultados demonstraram-se significativos para hemácias, hematocrito e hemoglobina nas variáveis hematológicas, AST e lactato para as variáveis bioquímicas e para o malondialdeido. Não foram encontradas diferenças estatísticas significativas nas comparações entre grupos de tratamento. Assim, pode-se concluir que não há diferença entre as duas terapias, indicando que as duas técnicas são eficazes para a aplicação da ozonioterapia em cavalos competidores de vaquejada.


Assuntos
Animais , Condicionamento Físico Animal/métodos , Peroxidação de Lipídeos , Estresse Oxidativo , Ozonioterapia , Cavalos/sangue , Fenômenos Bioquímicos , Testes Hematológicos/veterinária
18.
Ars vet ; 38(3): 121-126, 2022. ilus
Artigo em Português | VETINDEX | ID: biblio-1417126

RESUMO

Pitiose gástrica canina é uma afecção crônica granulomatosa causada pelo pseudo-fungo Pythium insidiosum que ocasiona espessamento trasnsmural do estômago. Relata-se um caso de gastrite fúngica em um canino dobermann de 1 ano, macho, atendido no Hospital Veterinário da Universidade Federal do Mato Grosso, campus Sinop-MT, com sinais clínicos de diarreia escura intermitente, regurgitação, êmese e anorexia progressiva por cerca de três meses. No exame ultrassonográfico, observou espessamento gástrico difuso. Devido ao prognóstico ruim, foi realizado eutanásia. Na macroscopia, havia espessamento difuso da parede do estômago e petéquias multifocais por toda a mucosa. Na microscopia havia acentuado infiltrado inflamatório granulomatoso por toda a submucosa e muscular. Foi realizado coloração de metenamina nitrato de prata de Grocott (GMS), com evidenciação de hifas cenocíticas, raras septação e diâmetro de 6-10µm. A confirmação do diagnóstico e identificação do agente foi realizado através Imuno-histoquímica com anticorpo primário para Pythium insidiosum.


Canine gastric pythiosis is a chronic granulomatous infection caused by the insidious pythi fungus that causes stomach thickening. We report a case of fungal gastritis in a 1-year-old male progressive Doberman canine treated at the Veterinary Hospital of the Federal University of Mato Grosso, Sinop-MT campus, with clinical signs of intermittent diarrhea, regurgitation, vomiting and anorexia for about three months. On ultrasound examination, diffuse gastric thickening was observed. Due to the poor prognosis, euthanasia was performed. Macroscopically, there was diffuse thickening of the stomach wall and multifocal petechiae throughout the mucosa. On microscopy, there was a marked granulomatous inflammatory infiltrate throughout the submucosa and muscle Production of Grocott silver nitrate methenamine (GMS) was performed with evidence of cenocytic hyphae, rare septation and diameter of 6-10µm. Confirmation of the diagnosis and identification of the agent was performed through Immunohistochemistry with primary antibody to Pythium insidiosum.


Assuntos
Animais , Masculino , Cães , Pythium , Pitiose/diagnóstico , Gastrite/veterinária , Doença Granulomatosa Crônica/veterinária
19.
J Phys Condens Matter, v. 34, n. 26, 264001, abr. 2022
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4286

RESUMO

Ordered mesoporous silica was proved to be an efficient oral adjuvant capable to deliver a wide in size variety of different antigens, promoting efficient immunogenicity. This material can be used in single or polivalent vaccines, which have been developed by a group of Brazilian scientists. The experiments performed with the model protein Bovine Serum Albumin (BSA) gave the first promissing results, that were also achieved by testing the virus like particle surface antigen of hepatitis B (HBsAg) and diphtheria anatoxin (dANA). Nanostructured ordered mesoporous silica, SBA-15 type, with bi-dimensional hexagonal porous symmetry was used to encapsulate the antigens either in the mesoporous (pore diameter ~10 nm) or macroporous ( pore diameter > 50 nm) regions. This silica vehicle proved to be capable to create an inflammatory response, did not exhibit toxicity, being effective to induce immunity in high and low responder mice towards antibody production. The silica particles are in the range of micrometer size, leaving no trace in mice organs due to its easy expulsion by faeces. The methods of Physics, usually employed to characterize the structure, composition and morphology of materials are of fundamental importance to develop proper oral vaccines in order to state the ideal antigen load to avoid clustering and to determine the rate of antigen release in different media mimicking body fluids.

20.
Braz J Med Biol Res ; 54(2): e10466, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33439935

RESUMO

Preoperative evaluation in elective surgeries has been associated with successful surgical treatment. However, there is no solid scientific evidence that screening for coronary artery disease (CAD) reduces surgical risk. The aims of this study were to describe the frequency of inappropriate investigation of obstructive CAD induced by pre-anesthetic assessment in individuals without cardiovascular symptoms (candidates for low- to intermediate-risk surgeries) and to evaluate predictors of this conduct. We performed a retrospective evaluation of medical records of anesthesiology services from patients undergoing pre-anesthesia assessment between May 2015 and May 2016, including those with functional capacity ≥4 metabolic equivalents without a diagnosis of heart disease. A total of 778 medical records (47±16 years of age, 62.6% female) were studied. A private hospital performed 50.1% of the surgeries and 60.4% were of intermediate risk. Only 2.7% (95%CI: 1.7-4.1%) were screened for CAD, and 91% of these requests were mediated by cardiology consultations performed during pre-anesthetic testing visits. Factors associated with screening for CAD were hypertension, diabetes, moderate systemic disease (ASA III), cardiac consultation, previous diagnosis of CAD, and admission to a private hospital. Independent predictors were private hospitals (OR: 3.9; 95%CI: 1.3-11.0), ASA III (OR: 5.3; 95%CI: 1.7-16.2), and hypertension (OR: 3.8; 95%CI: 1.5-9.8). The frequency of inappropriate requests for CAD screening in asymptomatic individuals without untreated systemic diseases was low in pre-anesthetic visits. Although infrequent, screening for CAD is more common in the private setting, in patients with poorer health status, and is usually prescribed during cardiology consultation.


Assuntos
Anestesia , Doença da Artéria Coronariana , Procedimentos Desnecessários , Adulto , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/cirurgia , Feminino , Cardiopatias , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
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