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1.
Microb Pathog ; 192: 106704, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38761893

RESUMO

The indiscriminate use of antimicrobials has led to the emergence of resistant bacteria, especially pathogenic strains of Escherichia coli, which are associated with diseases in animals and humans. The aim of the present study was to characterize E. coli isolates in calves with regards to the presence of virulence genes and investigate the resistance of the isolates to different antimicrobials. Between 2021 and 2023, 456 fecal samples were collected from calves in the Pantanal and Cerrado biomes of the state of Mato Grosso do Sul, Brazil. All samples were subjected to microbiological analysis and disc diffusion antibiogram testing. The polymerase chain reaction method was used to detect virulence genes. Bacterial growth was found in 451 of the 456 samples and biochemically identified as Escherichia coli. All 451 isolates (100 %) exhibited some phenotypic resistance to antimicrobials and 67.62 % exhibited multidrug resistance. The frequency of multidrug-resistant isolates in the Cerrado biome was significantly higher than that in the Pantanal biome (p = 0.0001). In the Cerrado, the most common pathotype was Shiga toxin-producing Escherichia coli (STEC) (28 %), followed by toxigenic Escherichia coli (ETEC) (11 %), enterohemorrhagic Escherichia coli (EHEC) (8 %) and enteropathogenic Escherichia coli (EPEC) (2 %). In most cases, the concomitant occurrence of pathotypes was more common, the most frequent of which were ETEC + STEC (33 %), ETEC + EHEC (15 %) and ETEC + EPEC (3 %). The STEC pathotype (30 %) was also found more frequently in the Pantanal, followed by EHEC (12 %), ETEC (9 %) and EPEC (6 %). The STEC pathotype had a significantly higher frequency of multidrug resistance (p = 0.0486) compared to the other pathotypes identified. The frequency of resistance was lower in strains from the Pantanal biome compared to those from the Cerrado biome. Although some factors are discussed in this paper, it is necessary to clarify the reasons for this difference and the possible impacts of these findings on both animal and human health in the region.


Assuntos
Antibacterianos , Doenças dos Bovinos , Farmacorresistência Bacteriana Múltipla , Infecções por Escherichia coli , Escherichia coli , Fezes , Testes de Sensibilidade Microbiana , Fatores de Virulência , Animais , Bovinos , Brasil , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Infecções por Escherichia coli/epidemiologia , Fezes/microbiologia , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/epidemiologia , Fatores de Virulência/genética , Escherichia coli Shiga Toxigênica/isolamento & purificação , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/efeitos dos fármacos , Escherichia coli Êntero-Hemorrágica/genética , Escherichia coli Êntero-Hemorrágica/isolamento & purificação , Escherichia coli Êntero-Hemorrágica/efeitos dos fármacos , Escherichia coli Enterotoxigênica/efeitos dos fármacos , Escherichia coli Enterotoxigênica/genética , Escherichia coli Enterotoxigênica/isolamento & purificação , Proteínas de Escherichia coli/genética
2.
Phys Chem Chem Phys ; 24(4): 2209-2218, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35013741

RESUMO

Exploration of new half-metallic materials for spintronic applications has drawn great attention from researchers. In this work, we investigate the structural, electronic, and magnetic properties of the NaMgO3 perovskite in the bulk and (001) surface conformations. The results show the half-metallic nature of bulk NaMgO3 generated by insulator spin-up channels with a large band gap of 6.08 eV and metallic spin-down channels. A total magnetic moment of 3 (µB) is obtained, which is produced mainly by O atoms with a local magnetic moment of 0.94 (µB). Once the bulk is cleaved along the (001) direction, atomic relaxation takes place to reach an equilibrium, where all constituent atoms exhibit an inward movement. Interestingly, the half-metallicity is retained from the bulk to the (001) surface conformation. The effects of slab termination and thickness on the surface energy, stability, band edges, spin-up energy gaps, and magnetic anisotropy will be also analyzed in detail. The results presented herein introduce the NaMgO3 perovskite as a promising half-metallic material to generate spin current in spintronic devices.

3.
J Chem Phys ; 156(23): 234106, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35732515

RESUMO

Dispersion interactions are one of the components of van der Waals (vdW) forces that play a key role in the understanding of intermolecular interactions in many physical, chemical, and biological processes. The theory of dispersion forces was developed by London in the early years of quantum mechanics. However, it was only in the 1960s that it was recognized that for molecules lacking an inversion center, such as chiral and helical molecules, there are chirality-sensitive corrections to the dispersion forces proportional to the rotatory power known from the theory of circular dichroism and with the same distance scaling law R-6 as the London energy. The discovery of the chirality-induced spin selectivity effect in recent years has led to an additional twist in the study of chiral molecular systems, showing a close relation between spin and molecular geometry. Motivated by it, we propose in this investigation to describe the mutual induction of charge and spin-density fluctuations in a pair A-B of chiral molecules by a simple physical model. The model assumes that the same fluctuating electric fields responsible for vdW forces can induce a magnetic response via a Rashba-like term so that a spin-orbit field acting on molecule B is generated by the electric field arising from charge density fluctuations in molecule A (and vice versa). Within a second-order perturbative approach, these contributions manifest as an effective intermolecular exchange interaction. Although expected to be weaker than the standard London forces, these interactions display the same R-6 distance scaling.


Assuntos
Teoria Quântica , Londres , Estereoisomerismo
4.
Lasers Med Sci ; 35(4): 777-788, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31768691

RESUMO

To date, there is no compilation of evidence-based information associating photobiomodulation effect and salivary glands. This systematic review aims to assess photobiomodulation effect of low intensity laser on salivary glands in the presence of systemic diseases. MEDLINE databases were searched in duplicate through December 2018. In vivo studies and clinical trials were included if photobiomodulation was performed in salivary glands of animal (rat or mice) or human in the presence of systemic disease. The methodological quality was assessed in duplicate using the modified Newcastle-Ottawa scale (NOS). Search strategy identified 483 potentially eligible articles, and 449 were included. The Boolean search naturally leads to a high amount of works the majority of which were excluded because the analysis of the title and abstract demonstrated it was not focusing on PBM. Only 34 studies were selected for the full-text analysis, of which 5 were excluded due to non-use of photobiomodulation, 4 due to lack of control group, 2 because they were studies of cell cultures and 1 because they did not have the total of animals used. Thus, 21 papers were included for the critical evaluation of the impact of photobiomodulation on the major salivary glands; the studies used rats (n = 10) and humans (n = 11). Although studies reported an increase in the salivary rate, decrease in pain, and increase in quality of life after the PBM, the lack of standards for the application of light and reporting of the parameters, make it hard to reproduce the results. This topic is still in need for further research.


Assuntos
Terapia com Luz de Baixa Intensidade , Glândulas Salivares/efeitos da radiação , Animais , Ensaios Clínicos como Assunto , Humanos , Camundongos , Dor/radioterapia , Qualidade de Vida , Ratos
5.
Genet Mol Res ; 16(1)2017 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-28340277

RESUMO

This study aimed to evaluate the immunomodulatory and neuroprotective effects of allogeneic and cryopreserved mesenchymal stem cells (MSCs) on spinal cord injury. A total of 120 rats were distributed into the following groups: negative control (NC) - without injury, positive control (PC) - with injury without treatment, and group treated with MSC (GMSC) - with injury and treated. Motor function was evaluated by the BBB test at 24, 48, and 72 h and at 8 and 21 postoperative days. Spinal cords were evaluated by histopathology and immunohistochemistry to determine the expression of CD68, NeuN, and GFAP. IL-10, TNF-α, IL-1ß, TGF-ß, BDNF, GDNF, and VEGF expression was quantified by RT-PCR. The GMSC presented higher scores for motor function at 72 h and 8 and 21 days after injury, lower expression of CD68 at 8 days, and lower expression of GFAP at 21 days compared to the PC. In addition, higher expression of NeuN and lower degeneration of the white matter occurred at 21 days. The GMSC also showed higher expression of IL-10 24 h after injury, GDNF at 48 h and 8 days, and VEGF at 21 days. Moreover, lower expression of TNF-α was observed at 8 and 21 days and TGF-ß at 24 h and 21 days. There were no differences in the expression of IL-1ß and BDNF between the GMSC and PC. Thus, cryopreserved MSCs promote immunomodulatory and neuroprotective effects in rats with spinal cord injury by increasing IL-10, GDNF, and VEGF expression and reducing TNF-α and TGF-ß expression.


Assuntos
Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/fisiologia , Medicina Regenerativa/métodos , Traumatismos da Medula Espinal/terapia , Animais , Criopreservação/métodos , Modelos Animais de Doenças , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Interleucina-10/metabolismo , Masculino , Células-Tronco Mesenquimais/imunologia , Células-Tronco Mesenquimais/metabolismo , Fármacos Neuroprotetores/imunologia , Ratos , Ratos Endogâmicos Lew , Traumatismos da Medula Espinal/imunologia , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Reprod Domest Anim ; 51(5): 827-30, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27453486

RESUMO

Paraoxonase-1 (PON1) is an enzyme found in serum and follicular fluid that protects cell membrane and circulating lipids against oxidative damage. The aims of this study were to measure the direct effects of recombinant PON1 (rPON1) on bovine oocyte maturation at the molecular level (gene expression) and to measure the carry-over effects of PON1 on pre-implantation embryo development in vitro. COCs were submitted to IVM with the addition of 0.0, 0.02, 0.04 and 0.08 mg ml(-1) of rPON1, corresponding to an average PON1 arylesterase enzyme activity of 2.2 ± 0.4, 15.5 ± 1.5, 30.2 ± 3.0 and 57.9 ± 5.0 U ml(-1) , respectively. The results indicated that addition of rPON1 during IVM improved embryo development in a dose-dependent manner as D7 embryo development was 22.2%, 29.4%, 32.2% and 37.0% for the treatment groups, respectively (p = 0.02). In conclusion, addition of PON1 enzyme during IVM exerted dose-related positive effects on embryo development rates to blastocysts.


Assuntos
Arildialquilfosfatase/farmacologia , Bovinos/embriologia , Técnicas de Cultura Embrionária/veterinária , Técnicas de Maturação in Vitro de Oócitos/veterinária , Animais , Meios de Cultura , Células do Cúmulo/efeitos dos fármacos , Embrião de Mamíferos/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos
7.
Genet Mol Res ; 15(4)2016 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-27813557

RESUMO

Streams are very important environments for Neotropical freshwater fish fauna, and possess a high number of species. These small drainages are also highlighted by their intrinsic biological and physicochemical features; however, knowledge on the genetic distribution of fish in these drainages is limited. Therefore, in the present study, RAPD (random amplified polymorphic DNA) and microsatellite markers were used to analyze population differentiation and gene flow of Astyanax altiparanae and Geophagus brasiliensis from three sites (high, medium, and low) throughout the Penacho stream (about 32 km long), which is a Neotropical stream. Both markers revealed higher levels of genetic diversity levels for A. altiparanae (: 90.05; HS: 0.350) compared to G. brasiliensis (: 30.43; HS: 0.118), which may be related to the particular biology of each species. AMOVA revealed significant genetic variation among populations of each species. All pairwise ΦST values were significant, ranging from 0.020 to 0.056 for A. altiparanae samples, and from 0.065 to 0.190 for G. brasiliensis samples. Bayesian clustering analysis corroborated these results and revealed clusters of both A. altiparanae (two based on RAPD data) and G. brasiliensis (two based on RAPD data and three on microsatellite data). Gene flow estimates showed that there were similar rates of migration among A. altiparanae samples and low rates of migration among some G. brasiliensis samples. These results suggest patterns of fine-scale genetic structure for both species in the Penacho stream. This information may enhance knowledge of Neotropical streams and may be useful for future management and conservation activities.


Assuntos
Characidae/genética , Ciclídeos/genética , Genética Populacional , Repetições de Microssatélites/genética , Animais , Água Doce , Fluxo Gênico , Técnica de Amplificação ao Acaso de DNA Polimórfico , Rios
8.
Int Endod J ; 48(9): 878-87, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25266756

RESUMO

AIM: To investigate whether single nucleotide polymorphisms (SNPs) within the interleukin-1 gene cluster (IL1) are associated with the occurrence and severity of inflammatory external root resorption (IERR) after replantation of avulsed permanent teeth. METHODOLOGY: Indexes of IERR were radiographically assessed in 182 mature replanted permanent teeth from 146 patients at the onset of endodontic therapy. DNA was extracted from buccal mucosa cells and genotyped using TaqMan probes-based assays for the SNPs IL1A -889C/T (rs 180058), IL1B +3954C/T (rs1143634) and IL1RN +2018C/T (rs419598). Teeth were grouped into two categories: IERR absent to mild (indexes ≤ 4) and moderate to severe IERR (indexes > 4). Genetic variations in the IL1 gene cluster were tested for their effect on the occurrence and extension of IERR using the GEE model (generalized estimation equation). Patient's age at the moment of injury, timing of pulpectomy, extra-alveolar period and storage condition of the avulsed teeth was included as possible confounders. RESULTS: No association was found between SNPs IL1A -889C/T, IL1B +3954C/T (rs1143634) and IL1RN +2018C/T (rs419598) and IERR indexes. Timing of pulpectomy (OR 3.5 IC 95% 2.0-6.2 P < 0.001) and patient's age at the moment of trauma (OR 0.29 IC 95% 0.12-0.67 P = 0.004) significantly affected the risk of developing severe IERR. CONCLUSIONS: While timing of pulpectomy and patient's age at the moment of trauma were confirmed as important risk factors, SNPs within the IL1 gene cluster did not affect the susceptibility for IERR after replantation of permanent teeth.


Assuntos
Interleucina-1/genética , Reabsorção da Raiz/genética , Reimplante Dentário/métodos , Adolescente , Adulto , Fatores Etários , Brasil , Criança , Feminino , Seguimentos , Humanos , Masculino , Família Multigênica , Polimorfismo de Nucleotídeo Único , Pulpectomia , Fatores de Risco , Reabsorção da Raiz/etiologia , Fatores de Tempo , Avulsão Dentária/terapia
9.
Genet Mol Res ; 14(4): 15301-11, 2015 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-26634494

RESUMO

Each year, approximately 170 million metric tons of chemical fertilizer are consumed by global agriculture. Furthermore, some chemical fertilizers contain toxic by-products and their long-term use may contaminate groundwater, lakes, and rivers. The use of plant growth-promoting bacteria may be a cost-effective strategy for partially replacing conventional chemical fertilizers, and may become an integrated plant nutrient solution for sustainable crop production. The main direct bacteria-activated mechanisms of plant growth promotion are based on improvement of nutrient acquisition, siderophore biosynthesis, nitrogen fixation, and hormonal stimulation. The aim of this study was to isolate and identify bacteria with growth-promoting activities from sugarcane. We extracted the bacterial isolate SCB4789F-1 from sugarcane leaves and characterized it with regard to its profile of growth-promoting activities, including its ability to colonize Arabidopsis thaliana. Based on its biochemical characteristics and 16S rDNA sequence analysis, this isolate was identified as Pantoea ananatis. The bacteria were efficient at phosphate and zinc solubilization, and production of siderophores and indole-3-acetic acid in vitro. The isolate was characterized by Gram staining, resistance to antibiotics, and use of carbon sources. This is the first report on zinc solubilization in vitro by this bacterium, and on plant growth promotion following its inoculation into A. thaliana. The beneficial effects to plants of this bacterium justify future analysis of inoculation of economically relevant crops.


Assuntos
Pantoea/isolamento & purificação , Reguladores de Crescimento de Plantas/isolamento & purificação , Saccharum/crescimento & desenvolvimento , Saccharum/microbiologia , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/microbiologia , Ácidos Indolacéticos/metabolismo , Fixação de Nitrogênio/fisiologia , Pantoea/genética , Fosfatos/metabolismo , Reguladores de Crescimento de Plantas/genética , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , RNA Ribossômico 16S/genética , Saccharum/metabolismo , Sideróforos/metabolismo , Zinco/metabolismo
10.
Nutr Metab Cardiovasc Dis ; 24(6): 606-13, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24602606

RESUMO

BACKGROUND & AIMS: Butyrate is a four-carbon fatty acid that presents anti-inflammatory, anti-oxidative and apoptotic properties in colon and several cell lines. Because atherosclerosis has important oxidative and inflammatory components, butyrate could reduce oxidation and inflammation, impairing atherogenesis. We evaluated the effects of butyrate supplementation of butyrate on atherosclerosis and its mechanisms of action. METHODS AND RESULTS: ApoE knockout mice were fed on chow diet or 1% butyrate-supplemented chow diet (Butyrate) for 10 weeks to assess atherosclerosis lesions area and inflammatory status. Macrophage and endothelial cells were also pretreated with butyrate (0.5 mM) for 2 h before oxLDL stimulation to study oxLDL uptake and pro and anti-inflammatory cytokine production. Butyrate reduced atherosclerosis in the aorta by 50%. In the aortic valve, butyrate reduced CCL2, VCAM1 and MMP2 productions in the lesion site, resulting in a lower migration of macrophage and increased collagen depositions in the lesion and plaque stability. When EA.hy926 cells were pretreated with butyrate, oxLDL uptake, CD36, VCAM1, CCL2 TNF, IL1ß and IL6 productions were reduced, whereas IL10 production was increased. These effects were accompanied by a lower activation of NFκB due to a lower nuclear translocation of the p65 subunit. CONCLUSION: Oral butyrate is able to slow the progression of atherosclerosis by reducing adhesion and migration of macrophages and increasing plaque stability. These actions are linked to the reduction of CD36 in macrophages and endothelial cells, decreased pro-inflammatory cytokines and lower activation of NFκB all of these data support a possible role for butyrate as an atheroprotective agent.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Antioxidantes/uso terapêutico , Aterosclerose/dietoterapia , Ácido Butírico/uso terapêutico , Suplementos Nutricionais , Placa Aterosclerótica/prevenção & controle , Fator de Transcrição RelA/antagonistas & inibidores , Animais , Anti-Inflamatórios não Esteroides/metabolismo , Antioxidantes/metabolismo , Aorta/imunologia , Aorta/metabolismo , Aorta/patologia , Valva Aórtica/imunologia , Valva Aórtica/metabolismo , Valva Aórtica/patologia , Aterosclerose/imunologia , Aterosclerose/metabolismo , Aterosclerose/fisiopatologia , Ácido Butírico/metabolismo , Antígenos CD36/antagonistas & inibidores , Antígenos CD36/metabolismo , Adesão Celular , Linhagem Celular , Movimento Celular , Núcleo Celular , Células Cultivadas , Endotélio Vascular/imunologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Humanos , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/patologia , Masculino , Camundongos Knockout , Placa Aterosclerótica/etiologia , Transporte Proteico , Fator de Transcrição RelA/metabolismo
11.
Braz J Biol ; 84: e278004, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511776

RESUMO

In this study, our objective was to conduct a comprehensive phytochemical analysis, determine toxicity levels, and assess the antioxidant and antimicrobial properties of extracts derived from the leaves of Dipteryx alata Vogel, a native species of the Brazilian cerrado flora. Three distinct extracts were prepared utilizing assisted ultrasound and the Soxhlet apparatus, namely, Ultrasound Crude Extract (UCE), Soxhlet Crude Extract (SCE), and the Soxhlet Ethanol Extract (SEE). The phytochemical analysis revealed the presence of flavonoids, tannins, phytosterols, and saponins in all extracts. Additionally, alkaloids were specifically identified in the SCE and SEE extracts. In the analysis using LC-DAD, the compounds gallic acid, rutin, quercetin, luteolin and kampefrol were determined in higher concentrations in the SCE, followed by the SEE and UCE, respectively. The GC-MS analysis revealed the presence of campesterol, stigmasterol and ß-sitosterol in all extracts, with UCE and SCE showing a higher concentration of ß-sitosterol. SCE showed the highest concentration of all identified compounds. In the analysis of antioxidant activity by DPPH• and ABTS•+, SEE showed greater efficiency (IC50 = 2.98 ± 2.92 and 6.57 ± 0.89 µg/mL, respectively). In the toxicity test with Allium cepa, all extracts stimulated root growth at 50 g/mL; UCE and SEE stimulated root growth at 250 g/mL; and SEE inhibited root growth at 750 g/mL. In the Artemia salina toxicity, all extracts were non-toxic. Antibacterial activity was identified in the microorganisms S. aureus and S. mutans; however, the extracts did not show antifungal action against the strain of C. albicans. The extracts of D. alata have therapeutic potential for applicability in dentistry.


Assuntos
Anti-Infecciosos , Dipteryx , Antioxidantes/química , Extratos Vegetais/química , Staphylococcus aureus , Compostos Fitoquímicos/análise , Anti-Infecciosos/toxicidade , Etanol
12.
Braz J Biol ; 84: e279536, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597531

RESUMO

Planting with higher density in sugarcane is one of the practices used to overcome low productivity. However, this planting material is equivalent to 25% of the total cost of production, being one of the main expenses for cultivation. In this sense, the present work aims to evaluate the productivity and economic viability of sugarcane as a function of planting density. The experiment was carried out at Usina Monte Alegre in the municipality of Mamanguape, Paraíba, Brazil, from March 2021 to January 2022 with the variety RB92579. Seven planting density were studied: T1: 7 gems m-1, T2: 10 gems m-1, T3: 12 gems m-1, T4: 11 gems m-1, T5: 15 gems m-1, T6: 17 gems m-1, T7: 24 gems m-1, in randomized blocks with four replications. Growth, productivity and economic viability were evaluated. The highest productivity of cane and sugar, 77.69 ton ha-1 and 10.390 ton ha-1, respectively, was with planting density of 17 and 24 gems-1. While the minimum productivity of cane (61.313 ton ha-1) and sugar (7.924 ton ha-1) was recorded at sowing density of 7 and 11 gems-1. However, cultivation density with 7 and 10 gems m-1 were the ones that provided the highest profitability around 50%, followed by density of 12, 15 and 17 gems m-1 with an average of 45% profit and 11 and 24 gems m-1 with the lowest proportion of profit on average 38%. The cultivation with 17 gems m-1 of cane provides in cane-plant, variety RB92579, greater productivity with a profit rate of 45%, being the most suitable.


Assuntos
Saccharum , Açúcares , Brasil
13.
J Clin Microbiol ; 51(4): 1250-2, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23345296

RESUMO

CLSI method M27-A3 is not available for use with dimorphic fungi, such as those of the Paracoccidioides genus. In this study, we developed a microdilution method and added the alamarBlue reagent to test the responses of Paracoccidioides brasiliensis and Paracoccidioides lutzii against amphotericin B and itraconazole antifungals. The test proved to be sensitive, practical, and inexpensive and can be used to monitor the activity of low-growth microorganisms and their response to various drugs.


Assuntos
Antifúngicos/farmacologia , Oxazinas/metabolismo , Paracoccidioides/efeitos dos fármacos , Coloração e Rotulagem/métodos , Xantenos/metabolismo , Anfotericina B/farmacologia , Humanos , Itraconazol/farmacologia , Testes de Sensibilidade Microbiana/métodos , Paracoccidioides/crescimento & desenvolvimento , Paracoccidioides/metabolismo
14.
Reprod Domest Anim ; 48(4): 691-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23369109

RESUMO

Although thyroid dysfunction occurs frequently in humans and some animal species, the mechanisms by which hypo- and hyperthyroidism affect the corpus luteum have not been thoroughly elucidated. This study evaluated the levels of proliferative activity, angiogenesis, apoptosis and expression of cyclooxygenase-2 in the corpus luteum of female rats with thyroid dysfunction. These processes may be important in understanding the reproductive changes caused by thyroid dysfunction. A total of 18 adult female rats were divided into three groups (control, hypothyroid and hyperthyroid) with six animals per group. Three months after treatment to induce thyroid dysfunction, the rats were euthanized in the dioestrus phase. The ovaries were collected and immunohistochemically analysed for expression of the cell proliferation marker CDC-47, vascular endothelial growth factor (VEGF), VEGF receptor Flk-1 and cyclooxygenase-2 (COX-2). Apoptosis was evaluated using the TUNEL assay. Hypothyroidism reduced the intensity and area of COX-2 expression in the corpus luteum (p < 0.05), while hyperthyroidism did not alter COX-2 expression in the dioestrus phase. Hypothyroidism significantly reduced the expression of CDC-47 in endothelial cells and pericytes in the corpus luteum, whereas hyperthyroidism did not induce a detectable change in CDC-47 expression (p > 0.05). Hypothyroidism reduced the level of apoptosis in luteal cells (p < 0.05) and increased VEGF expression in the corpus luteum. In contrast, hyperthyroidism increased the level of apoptosis in the corpus luteum (p < 0.05). In conclusion, thyroid dysfunction differentially affects the levels of proliferative activity, angiogenesis and apoptosis and COX-2 expression in the corpus luteum of female rats.


Assuntos
Corpo Lúteo/patologia , Corpo Lúteo/fisiopatologia , Ciclo-Oxigenase 2/análise , Hipertireoidismo/fisiopatologia , Hipotireoidismo/fisiopatologia , Animais , Apoptose , Proliferação de Células , Corpo Lúteo/química , Feminino , Hipertireoidismo/induzido quimicamente , Hipertireoidismo/patologia , Hipotireoidismo/induzido quimicamente , Hipotireoidismo/patologia , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Componente 7 do Complexo de Manutenção de Minicromossomo/análise , Neovascularização Fisiológica , Propiltiouracila/administração & dosagem , Ratos , Ratos Wistar , Tiroxina/administração & dosagem , Tiroxina/sangue , Fator A de Crescimento do Endotélio Vascular/análise , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/análise
15.
Reprod Domest Anim ; 48(3): e33-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23057740

RESUMO

Here is reported a disorder of sex development found in the Portuguese Lusitano horse breed. The complex genital phenotype included mammary glands, abdominal testes without epididymis, connected through oviducts to pelvic hypoplastic uterine horns and fused vulvar labia majora from which protruded ventrally a penis-like structure. This structure was presented in a reversed position, the urethral opening placed dorsally in the glans. However, it was functional both for micturition and erection. The horse exhibited female micturition posture and aggressive male-like behaviour, including flehmen, mounting, thrusting and flagging of the tail. Plasma testosterone concentrations were below detection limits and the genetic evaluation revealed a 64, XX, SRY-negative karyotype. Surgery consisted in the removal of abdominal gonads followed by amputation of the penis and repositioning of the urethra. This case of reversion between the chromosomal and gonadal sex, associated with mixed anatomical and behavioural phenotype, illustrates that development of the testes may occur in the absence of the SRY gene and that other genetic and cellular pathways leading to gonad differentiation should be investigated.


Assuntos
Doenças dos Cavalos/patologia , Cavalos/genética , Cariótipo , Transtornos Ovotesticulares do Desenvolvimento Sexual/veterinária , Animais , Feminino , Doenças dos Cavalos/genética , Masculino , Transtornos Ovotesticulares do Desenvolvimento Sexual/patologia , Comportamento Sexual Animal
16.
Braz J Biol ; 83: e270316, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37162094

RESUMO

Ganoderma lucidum is a medicinal mushroom widely recognized as a source of biomolecules with pharmacological properties, however, little is known about the factors that influence the synthesis of bioactive proteins by this fungus when cultivated under submerged fermentation. The objective of this work was to evaluate the production of mycelial biomass and intracellular proteases and protease inhibitors by G. lucidum cultivated under different submerged fermentation conditions. The cultivation was carried out in a medium composed of glucose (10 or 20 g.L-1), soy peptone (2.5 or 5 g.L-1) and yeast extract (5 g.L-1), with incubation under agitation (120 rpm) and non-agitation, totaling 8 experimental conditions. Biomass production was determined from the dry weight, while glucose consumption was estimated by quantification of reducing sugars. The proteins were extracted in NaCl (0.15 M), and the protein extracts were submitted to protein quantification by the Bradford method, total proteolytic activity using azocasein, caseinolytic and fibrinolytic activity in Petri dishes, activity of serine (trypsin and chymotrypsin) and cysteine (papain) protease inhibitors. Cultivation in agitated condition showed higher biomass production with a maximum value of 7 g.L-1, in addition to higher activities of trypsin, chymotrypsin and papain inhibitors, with 154 IU.mg-1, 153 IU.mg-1 e 343 IU.mg-1 of protein, respectively. The non-agitated condition showed a greater potential for obtaining proteins, total proteases, caseinolytic and fibrinolytic enzymes, with maximum values of 433 mg.g-1 of extract, 71 U.mL-1 of extract, 63.62 mm2 and 50.27 mm2, respectively. Thus, a medium composed of soy peptone, yest extract and glucose in a 1:2:4 proportion is recommended, under agitation to produce protease inhibitors, and the non-agitated condition when the target is, mainly caseinolytic and fibrinolytic enzymes.


Assuntos
Peptídeo Hidrolases , Reishi , Fermentação , Inibidores de Proteases/farmacologia , Tripsina , Papaína , Quimotripsina , Peptonas , Biomassa
17.
Braz J Med Biol Res ; 56: e12564, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37194834

RESUMO

The need to fully exploit fishing resources due to increasing production and consequent waste generation requires research to promote the sustainability of the fishing industry. Fish waste from the industry is responsible for relevant environmental contamination. However, these raw materials contain high amounts of collagen and other biomolecules, being attractive due to their industrial and biotechnological applicability. Thus, to reduce the waste from pirarucu (Arapaima gigas) processing, this study aimed to obtain collagen from pirarucu skin tissue. The extraction process used 0.05 M sodium hydroxide, 10% butyl alcohol, and 0.5 M acetic acid, with extraction temperature of 20°C. The obtained yield was 27.8%, and through sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), it was determined that the collagen obtained was type I. This study showed that collagen solubility was highest at pH 3 and the lowest solubility was at concentrations of 3% sodium chloride. The denaturation temperature of collagen was 38.1°C, and its intact molecular structure was observed using the Fourier transform infrared spectrophotometry technique with an absorption radius of 1. The results showed that it was possible to obtain collagen from pirarucu skin at 20°C, which has the typical characteristics of commercial type I collagen. In conclusion, the procedures used may be considered to be an interesting alternative for collagen extraction, a new product obtained from the processing of fish waste.


Assuntos
Colágeno , Proteínas de Peixes , Animais , Proteínas de Peixes/análise , Proteínas de Peixes/química , Colágeno Tipo I , Pele/química , Peixes , Água Doce
18.
Biofouling ; 28(7): 711-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22784100

RESUMO

The pathogenic fungus, Histoplasma capsulatum, causes the respiratory and systemic disease 'histoplasmosis'. This disease is primarily acquired via inhalation of aerosolized microconidia or hyphal fragments of H. capsulatum. Evolution of this respiratory disease depends on the ability of H. capsulatum yeasts to survive and replicate within alveolar macrophages. It is known that adhesion to host cells is the first step in colonization and biofilm formation. Some microorganisms become attached to biological and non-biological surfaces due to the formation of biofilms. Based on the importance of biofilms and their persistence on host tissues and cell surfaces, the present study was designed to investigate biofilm formation by H. capsulatum yeasts, as well as their ability to adhere to pneumocyte cells. H. capsulatum biofilm assays were performed in vitro using two different clinical strains of the fungus and biofilms were characterized using scanning electron microscopy. The biofilms were measured using a 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium-hydroxide (XTT) reduction assay. The results showed that both the H. capsulatum strains tested were very efficient at adhering to host cells and forming biofilm. Therefore, this is a possible survival strategy adopted by this fungus.


Assuntos
Células Epiteliais Alveolares/microbiologia , Biofilmes , Histoplasma/patogenicidade , Células Epiteliais Alveolares/metabolismo , Adesão Celular , Linhagem Celular , Histoplasma/metabolismo , Histoplasma/fisiologia , Histoplasmose/microbiologia , Interações Hospedeiro-Patógeno , Humanos , Microscopia Eletrônica de Varredura , Sais de Tetrazólio/metabolismo
19.
Genet Mol Res ; 11(4): 3798-813, 2012 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-22930436

RESUMO

Eucalyptus is a genus widely cultivated in many tropical and subtropical regions of the world as one of the main sources of raw materials for the pulp and paper industry. Identification of clones and selection of genotypes with desirable agronomic characteristics would be useful. We assessed eucalyptus full-sibs that varied in wood quality, using a combination of two-dimensional gel electrophoresis and mass spectrometry to identify differentially expressed proteins as candidates for quality markers. Thirty-one differently expressed proteins were identified, including three proteins of clone X1, four of clone X2, and 12 each of clones X3 and X4. These proteins are involved in various biological processes, including polyphosphate biosynthesis, catalytic activity, nucleotide excision repair, cellular metabolic processes, cell redox homeostasis, response to salt stress, response to temperature, oxidation and reduction processes, cellular water homeostasis, and protein phosphorylation. In the cambial region of each clone, the proteins ketol-acid reductoisomerase, uncharacterized protein MG428, receptor-like serine/threonine-protein kinase and a heat shock protein were found in larger quantities in clone X4 than in clone X1. These proteins are known to be related to protection against oxidative stress and biosynthesis of lignin. A high buildup of proteins involved in response to stress in the cambial region of eucalyptus would indicate clones with undesirable characteristics for use in the pulp and paper industry.


Assuntos
Eucalyptus/metabolismo , Indústrias , Estresse Oxidativo , Papel/normas , Proteínas de Plantas/metabolismo , Cromatografia Líquida , Células Clonais , Eletroforese em Gel Bidimensional , Proteínas de Plantas/classificação , Espectrometria de Massas por Ionização por Electrospray , Madeira/metabolismo , Xilema/metabolismo
20.
J Fish Biol ; 80(5): 1678-703, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22497403

RESUMO

Recent regulations have required European nations to report commercial landings of Rajidae (skates) to species level since 2008. Morphological similarities between some species, variability in colouration and regional differences in common names may compromise the accuracy of some of these data. An increased proportion of rajid landings reported by the U.K. (England, Wales and Northern Ireland) are now reported to species level (42% in 2008, rising to 92% in 2010). Recent landings (2007-2010) of Rajidae by the U.K. indicated that the majority of reported landings were made by otter trawl (55·9%), tangle and gillnet (18·7%) and beam trawl (15·5%). Approximately 70% of recent landings originated from four ICES Divisions: the Irish Sea (VIIa), western English Channel (VIIe), Bristol Channel (VIIf) and southern North Sea (IVc). Recent species-specific landings of Rajidae are appraised in terms of the species reported and the overall composition, and potential problems identified. Data from observer trips have been used to estimate the species composition of Rajidae taken in some of the main commercial fisheries operating around the British Isles, and these data are compared to landings. Although there was typically broad agreement between these data sets in terms of the main species landed, misidentification issues were apparent and Rajidae with highly patchy distributions may be under-represented in observer data. Data from observer trips were also used to examine the discard and retention pattern. Most rajid species were first retained from total lengths, L(T) , of 27-34 cm, with 50% retention occurring at between 49 and 51 cm and near-full retention at L(T) of 60-67 cm. Beam trawls captured a higher proportion of smaller individuals, whilst gillnets (>150 mm mesh size) caught proportionally more larger rajids.


Assuntos
Pesqueiros/estatística & dados numéricos , Rajidae/classificação , Animais , Oceano Atlântico , Biodiversidade , Biomassa , Geografia , Mar do Norte , Reino Unido
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