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101.
Flávio Teles Tarcilo Machado da Silva Francisco Pessoa da Cruz Júnior Vitor Hugo Honorato Henrique de Oliveira Costa Ana Paula Fernandes Barbosa Sabrina Gomes de Oliveira Zenaldo Porfírio Alexandre Braga Libório Raquel Lerner Borges Camilla Fanelli 《PloS one》2015,10(1)
The pathogenic role of inflammation and oxidative stress in chronic kidney disease (CKD) is well known. Anti-inflammatories and antioxidant drugs has demonstrated significant renoprotection in experimental nephropathies. Moreover, the inclusion of natural antioxidants derived from food and herbal extracts (such as polyphenols, curcumin and lycopene) as an adjuvant therapy for slowing CKD progression has been largely tested. Brazilian propolis is a honeybee product, whose anti-inflammatory, antimicrobial and antioxidant effects have been widely shown in models of sepsis, cancer, skin irritation and liver fibrosis. Furthermore, previous studies demonstrated that this compound promotes vasodilation and reduces hypertension. However, potential renoprotective effects of propolis in CKD have never been investigated. The aim of this study was to evaluate the effects of a subtype of Brazilian propolis, the Red Propolis (RP), in the 5/6 renal ablation model (Nx). Adult male Wistar rats underwent Nx and were divided into untreated (Nx) and RP-treated (Nx+RP) groups, after 30 days of surgery; when rats already exhibited marked hypertension and proteinuria. Animals were observed for 90 days from the surgery day, when Nx+RP group showed significant reduction of hypertension, proteinuria, serum creatinine retention, glomerulosclerosis, renal macrophage infiltration and oxidative stress, compared to age-matched untreated Nx rats, which worsened progressively over time. In conclusion, RP treatment attenuated hypertension and structural renal damage in Nx model. Reduction of renal inflammation and oxidative stress could be a plausible mechanism to explain this renoprotection. 相似文献
102.
Thiago Olitta Basso Fernanda Sgarbosa Gomes Mario Lucio Lopes Henrique Vianna de Amorim Gillian Eggleston Luiz Carlos Basso 《Antonie van Leeuwenhoek》2014,105(1):169-177
Bacterial contamination during industrial yeast fermentation has serious economic consequences for fuel ethanol producers. In addition to deviating carbon away from ethanol formation, bacterial cells and their metabolites often have a detrimental effect on yeast fermentative performance. The bacterial contaminants are commonly lactic acid bacteria (LAB), comprising both homo- and heterofermentative strains. We have studied the effects of these two different types of bacteria upon yeast fermentative performance, particularly in connection with sugarcane-based fuel ethanol fermentation process. Homofermentative Lactobacillus plantarum was found to be more detrimental to an industrial yeast strain (Saccharomyces cerevisiae CAT-1), when compared with heterofermentative Lactobacillus fermentum, in terms of reduced yeast viability and ethanol formation, presumably due to the higher titres of lactic acid in the growth medium. These effects were only noticed when bacteria and yeast were inoculated in equal cell numbers. However, when simulating industrial fuel ethanol conditions, as conducted in Brazil where high yeast cell densities and short fermentation time prevail, the heterofermentative strain was more deleterious than the homofermentative type, causing lower ethanol yield and out competing yeast cells during cell recycle. Yeast overproduction of glycerol was noticed only in the presence of the heterofermentative bacterium. Since the heterofermentative bacterium was shown to be more deleterious to yeast cells than the homofermentative strain, we believe our findings could stimulate the search for more strain-specific antimicrobial agents to treat bacterial contaminations during industrial ethanol fermentation. 相似文献
103.
Lucas Martins França Larissa Nara Costa Freitas Vinicyus Teles Chagas Caio Fernando Ferreira Coêlho Wermerson Assunção Barroso Graciomar Conceição Costa Lucilene Amorim Silva Victor Debbas Francisco Rafael Martins Laurindo Antonio Marcus de Andrade Paes 《Biochemical and biophysical research communications》2014
Non-alcoholic fatty liver disease (NAFLD) is intimately associated with insulin resistance and hypertriglyceridemia, whereas many of the mechanisms underlying this association are still poorly understood. In the present study, we investigated the relationship between microsomal triglyceride transfer protein (MTP) and markers of endoplasmic reticulum (ER) stress in the liver of rats subjected to neonatal monosodium l-glutamate (MSG)-induced obesity. At age 120 days old, the MSG-obese animals exhibited hyperglycemia, hypertriglyceridemia, insulin resistance, and liver steatosis, while the control (CTR) group did not. Analysis using fast protein liquid chromatography of the serum lipoproteins revealed that the triacylglycerol content of the very low-density lipoprotein (VLDL) particles was twice as high in the MSG animals compared with the CTR animals. The expression of ER stress markers, GRP76 and GRP94, was increased in the MSG rats, promoting a higher expression of X-box binding protein 1 (XBP-1), protein disulfide isomerase (PDI), and MTP. As the XBP-1/PDI/MTP axis has been suggested to represent a significant lipogenic mechanism in the liver response to ER stress, our data indicate that hypertriglyceridemia and liver steatosis occurring in the MSG rats are associated with increased MTP expression. 相似文献
104.
Jane Mello Lopes Cheila de Lima Boijink Luiz Henrique Florindo Cleo Alcantara Costa Leite Ana Lúcia Kalinin William K. Milsom Francisco Tadeu Rantin 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2010,180(6):797-811
In one series of experiments, heart frequency (f
H), blood pressure (P
a), gill ventilation frequency (f
R
), ventilation amplitude (V
AMP) and total gill ventilation (V
TOT) were measured in intact jeju (Hoplerythrinus unitaeniatus) and jeju with progressive denervation of the branchial branches of cranial nerves IX (glossopharyngeal) and X (vagus) without
access to air. When these fish were submitted to graded hypoxia (water PO2 ~140, normoxia to 17 mmHg, severe hypoxia), they increased f
R
, V
AMP, V
TOT and P
a and decreased f
H. In a second series of experiments, air-breathing frequency (f
RA), measured in fish with access to the surface, increased with graded hypoxia. In both series, bilateral denervation of all
gill arches eliminated the responses to graded hypoxia. Based on the effects of internal (caudal vein, 150 μg NaCN in 0.2 mL
saline) and external (buccal) injections of NaCN (500 μg NaCN in 1.0 mL water) on f
R
, V
AMP, V
TOT, P
a and f
H we conclude that the O2 receptors involved in eliciting changes in gill ventilation and associated cardiovascular responses are present on all gill
arches and monitor the O2 levels of both inspired water and blood perfusing the gills. We also conclude that air breathing arises solely from stimulation
of branchial chemoreceptors and support the hypothesis that internal hypoxaemia is the primary drive to air breathing. 相似文献
105.
106.
Jonny E. Scherwinski-Pereira Rodrigo S. da Guedes Paulo César P. FerminoJr Tatiane L. Silva Frederico Henrique S. Costa 《In vitro cellular & developmental biology. Plant》2010,46(4):378-385
An efficient procedure has been developed for inducing somatic embryogenesis and regeneration of plants from tissue cultures
of oil palm (Elaeis guineensis Jacq.). Thin transverse sections (thin cell layer explants) of different position in the shoot apex and leaf sheath of oil
palm were cultivated in Murashige and Skoog (MS) (Physiol Plant 15:473–497, 1962) medium supplemented with 0–450 μM picloram and 2,4-D with 3.0% sucrose, 500 mg L−1 glutamine, and 0.3 g L−1 activated charcoal and gelled with 2.5 g L−1 Phytagel. Embryogenic calluses were evaluated 12 wk after inoculation. Picloram (450 μM) was effective in inducing embryogenic
calluses in 41.5% of the basal explants. Embryogenic calluses were maintained on a maturation medium composed of basal media,
plus 0.6 μM NAA and 12.30 μM 2iP, 0.3 g L−1 activated charcoal, and 500 mg L−1 glutamine, with subcultures at 4-wk intervals. Somatic embryos were converted to plants on MS medium with macro- and micronutrients
at half-strength, 2% sucrose, and 1.0 g L−1 activated charcoal and gelled with 2.5 g L−1 Phytagel. 相似文献
107.
Ana Flávia Azevedo Carvalho Maurício Boscolo Roberto da Silva Henrique Ferreira Eleni Gomes 《Journal of microbiology (Seoul, Korea)》2010,48(4):452-459
An α-glucosidase enzyme produced by the fungus Thermoascus aurantiacus CBMAI 756 was purified by ultra filtration, ammonium sulphate precipitation, and chromatography using Q Sepharose, Sephacryl
S-200, and Superose 12 columns. The apparent molecular mass of the enzyme was 83 kDa as determined in gel electrophoresis.
Maximum activity was observed at pH 4.5 at 70°C. Enzyme showed stability stable in the pH range of 3.0–9.0 and lost 40% of
its initial activity at the temperatures of 40, 50, and 60°C. In the presence of ions Na+, Ba2+, Co2+, Ni2+, Mg2+, Mn2+, Al3+, Zn2+, Ca2+ this enzyme maintained 90–105% of its maximum activity and was inhibited by Cr3+, Ag+, and Hg2+. The enzyme showed a transglycosylation property, by the release of oligosaccharides after 3 h of incubation with maltose,
and specificity for short maltooligosaccharides and α-PNPG. The Km measured for the α-glucosidase was 0.07 μM, with a Vmax of 318.0 μmol/min/mg. 相似文献
108.
Kap‐Hoon Han Yoon‐Hee Chun Bárbara De Castro Pimentel Figueiredo Frederico Marianetti Soriani Marcela Savoldi Agostinho Almeida Fernando Rodrigues Charlie Timothy Cairns Elaine Bignell Jaqueline Moisés Tobal Maria Helena S. Goldman Jong‐Hwan Kim Yong‐Sun Bahn Gustavo Henrique Goldman Márcia Eliana Da Silva Ferreira 《Molecular microbiology》2010,75(6):1372-1388
Carbon dioxide (CO2) and its hydration product bicarbonate (HCO3‐) are essential molecules in various physiological processes of all living organisms. The reversible interconversion between CO2 and HCO3‐ is in equilibrium. This reaction is slow without catalyst, but can be rapidly facilitated by Zn2+‐metalloenzymes named carbonic anhydrases (CAs). To gain an insight into the function of multiple clades of fungal CA, we chose to investigate the filamentous fungi Aspergillus fumigatus and A. nidulans. We identified four and two CAs in A. fumigatus and A. nidulans, respectively, named cafA‐D and canA‐B. The cafA and cafB genes are constitutively, strongly expressed whereas cafC and cafD genes are weakly expressed but CO2‐inducible. Heterologous expression of the A. fumigatus cafB, and A. nidulans canA and canB genes completely rescued the high CO2‐requiring phenotype of a Saccharomyces cerevisiaeΔnce103 mutant. Only the ΔcafAΔcafB and ΔcanB deletion mutants were unable to grow at 0.033% CO2, of which growth defects can be restored by high CO2. Defects in the CAs can affect Aspergilli conidiation. Furthermore, A. fumigatusΔcafA, ΔcafB, ΔcafC, ΔcafD and ΔcafAΔcafB mutant strains are fully virulent in a low‐dose murine infection. 相似文献
109.
G Junior DS Araújo FR Almeida Junior NF Adi SS Cheung LM Fragoso SP Ramos CA Oliveira RH Santos CS Bacanelli G Soares CO Rosinha GM Fonseca AH 《Memórias do Instituto Oswaldo Cruz》2010,105(7):843-849
The sequencing of the complete genome of Anaplasma marginale has enabled the identification of several genes that encode membrane proteins, thereby increasing the chances of identifying candidate immunogens. Little is known regarding the genetic variability of genes that encode membrane proteins in A. marginale isolates. The aim of the present study was to determine the degree of conservation of the predicted amino acid sequences of OMP1, OMP4, OMP5, OMP7, OMP8, OMP10, OMP14, OMP15, SODb, OPAG1, OPAG3, VirB3, VirB9-1, PepA, EF-Tu and AM854 proteins in a Brazilian isolate of A. marginale compared to other isolates. Hence, primers were used to amplify these genes: omp1, omp4, omp5, omp7, omp8, omp10, omp14, omp15, sodb, opag1, opag3, virb3, VirB9-1, pepA, ef-tu and am854. After polimerase chain reaction amplification, the products were cloned and sequenced using the Sanger method and the predicted amino acid sequence were multi-aligned using the CLUSTALW and MEGA 4 programs, comparing the predicted sequences between the Brazilian, Saint Maries, Florida and A. marginale centrale isolates. With the exception of outer membrane protein (OMP) 7, all proteins exhibited 92-100% homology to the other A. marginale isolates. However, only OMP1, OMP5, EF-Tu, VirB3, SODb and VirB9-1 were selected as potential immunogens capable of promoting cross-protection between isolates due to the high degree of homology (over 72%) also found with A. (centrale) marginale. 相似文献
110.
Luiz Henrique Saes Zobiole Edicléia Aparecida Bonini Rubem Silvério de OliveiraJr. Robert John Kremer Osvaldo Ferrarese-Filho 《Acta Physiologiae Plantarum》2010,32(5):831-837
Farmers report that some glyphosate-resistant soybean varieties are visually injured by glyphosate. Glyphosate is the main
herbicide that directly affects the synthesis of secondary compounds. In this work, we evaluated the effect of increasing
rates of glyphosate on lignin and amino acid content, photosynthetic parameters and dry biomass in the early maturity group
cultivar BRS 242 GR soybean. Plants were grown in half-strength complete nutrient solution and subjected to various rates
of glyphosate either as a single or in sequential applications. All parameters evaluated were affected by increasing glyphosate
rates. The effects were more pronounced as glyphosate rates increased, and were more intense with a single total application
than sequential applications at lower rates. 相似文献