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61.
Vinicius Sousa Pietra Pedroso Márcia Carvalho Vilela Patrícia Campi Santos Patrícia Silva Cisalpino Milene Alvarenga Rachid Antônio Lúcio Teixeira 《Mycopathologia》2013,176(3-4):191-199
Background
Paracoccidioidomycosis is the most important systemic mycosis in South America. In the last decades, it was observed that central nervous system involvement is frequent, occurring in 12.5 % of the cases. The aim of this study was to report the early inflammatory changes associated with an experimental model of neuroparacoccidioidomycosis (NPCM).Methods
C57BL/6 mice were infected by intracranial route with 106 yeast cells of PB18 strain of Paracoccidioides brasiliensis. Leukocyte–endothelium interactions were assessed by intravital microscopy 1, 2, 4, and 8 weeks post-infection (p.i.). Chemokine/cytokine levels in the brain and histopathological changes were assessed 4 and 8 weeks p.i..Results
Intravital microscopy analysis revealed a progressive increase in leukocyte recruitment in the vessels of pia mater with a peak 4 weeks p.i. The chemokine CXCL9 was increased at 4 and 8 weeks p.i., while CCL2, CCL3, and CCL5 were increased at 8 weeks p.i. Histopathological analysis revealed the infiltration of inflammatory cells and the development of progressive granulomatous meningoencephalitis. CCL3 levels correlated with clinical manifestations of disease, as measured by the SHIRPA battery.Conclusions
The experimental model of NPCM showed increased leukocyte recruitment associated with increased expression of chemokines and nervous tissue inflammation which correlated with clinical manifestations of disease. 相似文献62.
Ígor B. Cursi Roberta Teixeira Silva Isabella Brasil Succi Andréa R. Bernardes-Engemann Rosane Orofino-Costa 《Mycopathologia》2013,175(1-2):75-82
Background
Onychomycosis by Neoscytalidium constitutes chronic infection of the nails, and its frequency has increased in recent decades. Currently, no effective standard treatment exists and literature data remain scarce. This work aimed to conduct a pilot project of combined treatment for this infection.Methods
Thirty patients were divided into three treatment groups: oral terbinafine plus ciclopirox nail lacquer twice a week; ciclopirox nail lacquer twice a week; and ciclopirox nail lacquer 5 days a week, all associated with nail abrasion when required, for 12 months, with 6 months posttreatment follow-up. Clinical and mycological criteria were used for evaluation.Results
Twenty-five patients completed the study. Significant clinical lesion reduction in disease occurred in all three treatment groups: 21 patients (84 %) entered the study with more than 50 % of diseased nail plate, at the end of treatment, and at 6-month follow-up, 84 and 96 %, respectively, presented less than 25 % nail lesion. Negative microscopy was observed in 36 % of the patients at the end of treatment and in 24 % of the patients at 6-month follow-up. At treatment completion (12 months), culture was negative in 21 patients (84 %) and in 18 (72 %) at follow-up. It was not possible to establish any clinical or mycological statistical differences between groups (p > 0.05). Global medical evaluation upon treatment completion revealed that one patient (4 %) presented complete cure, 8 (32 %) presented partial cure, 16 (64 %) presented therapeutic failure. At the end of follow-up period, 6 patients (24 %) were considered to have recurrence/reinfection.Conclusions
The results obtained at the 6-month period of follow-up showed marked improvement (96 % of clinical improvement and 72 % of negative culture) of the patients treated for onychomycosis caused by Neoscytalidium in the three tested groups with no statistical differences between them. Multicentric studies with greater number of patients enrolled are necessary to confirm these results. 相似文献63.
C. R. C. Moreno F. M. Louzada L. R. Teixeira F. Borges G. Lorenzi‐Filho 《Chronobiology international》2013,30(6):1295-1303
Recent studies suggest that short‐sleep duration is independently associated with obesity in the general population. The population of truck drivers is of particular interest, because they frequently work irregular shifts that in turn are associated with short‐sleep duration. In addition, truck drivers have a high prevalence of sedentary habits, poor diet, and obesity. The present study aimed at verifying the association between sleep patterns and factors associated with obesity in this population. The study sample consisted in 4,878 truck drivers who participated in a campaign promoted by a highway company in the State of São Paulo, Brazil. This campaign offered highway truck drivers a medical and laboratorial evaluation. The truck drivers completed a questionnaire concerning demographic data, sleep duration, consumption of medications, and medical problems, such as diabetes, cardiopathy, and hypertension; as well as the Berlin questionnaire, which is able to discriminate low and high risk for obstructive sleep apnea. Blood samples were collected to measure glucose and cholesterol levels. Also, body weight and height were registered to calculate the body mass index (BMI). The mean age (±SD) of the truck drivers studied was 40±10 years. Out of the truck drivers analyzed, 28.3% (n=1,379) had a BMI ≥30.0 Kg/m2 (obesity). Among the 4,878 drivers included in the study, 1,199 (24.6%) were on medications and 334 (6.8%) were diabetic. Drivers (26.9%) with the greater BMI had a short sleep length. The independent factors associated with obesity were sleep duration <8 h/day (OR=1.24), age >40 years (OR=1.20), glucose levels >200 (OR=2.02), cholesterol levels >240 (OR=1.57), snoring (OR=1.74), and hypertension (OR=2.14). Smoking was not associated with obesity (OR=0.69), and diabetes was considered a control variable. In conclusion, this study supports the hypothesis that short sleep duration as well as age >40 years are independently associated with obesity. This particular combination (short‐sleep duration and obesity) is independently associated with several healthcare problems, including high levels of cholesterol, glucose, snoring, and hypertension. However, due to the cross‐sectional nature of this study, no cause–effect relationship can be drawn from these results. 相似文献
64.
Cláudia Marques Diana Teixeira Ana Cunha Manuela Meireles Diogo Pestana Elisa Keating Conceição Calhau Rosário Monteiro Ana Faria 《Cell biology and toxicology》2013,29(4):293-302
Methotrexate (MTX) is broadly used in the treatment of chronic inflammatory diseases such as rheumatoid arthritis (RA). The prevalence of metabolic syndrome (MeS) in patients with this condition is relatively high. Given the importance of adipose tissue in the development of obesity metabolic complications, this study aimed to investigate the effect of methotrexate on preadipocyte proliferation, adipogenesis, and glucose uptake by adipocytes. 3T3-L1 preadipocytes proliferation was evaluated by sulforhodamine B staining and 3H-thymidine incorporation, after 24 or 48 h of treatment with MTX (0.1 and 10 μM). Preadipocytes were induced to differentiate with an appropriate adipogenic cocktail in the presence or absence of MTX. Adipogenesis was determined by measuring lipid accumulation after staining with oil red O. 3H-Deoxyglucose (3H-DG) uptake was determined by liquid scintillation counting. MTX treatment reduced culture protein content in a concentration-dependent manner and 3H-thymidine incorporation (P?<?0.05). MTX (0.1 μM) treatment increased lipid accumulation and basal 3H-DG uptake by adipocytes (P?<?0.05). In 0.1 μM MTX-treated adipocytes, insulin stimulation did not result in an increase of 3H-DG uptake, contrarily to what was observed in control cells. These results demonstrate that methotrexate interferes with adipocyte proliferation and promotes the hypertrophic growth of adipocytes. These molecular effects may have implications on metabolic profile of RA patients treated with MTX. 相似文献
65.
66.
Rosane Dias Costa Vanessa Amaral Mendon?a Frederico Marianetti Soriani Sandra Lyon Rachel Adriana Penido Ana Maria Duarte Dias Costa Marina Dias Costa Fabio de Souza Terra Mauro Martins Teixeira Carlos Mauricio de Figueiredo Antunes Antonio Lúcio Teixeira 《Memórias do Instituto Oswaldo Cruz》2013,108(8):1051-1056
Leprosy is an infectious and contagious spectral disease accompanied by a series of
immunological events triggered by the host response to the aetiologic agent,
Mycobacterium leprae . The induction and maintenance of the
immune/inflammatory response in leprosy are linked to multiple cell interactions and
soluble factors, primarily through the action of cytokines. The purpose of the
present study was to evaluate the serum levels of tumour necrosis factor (TNF)-α and
its soluble receptors (sTNF-R1 and sTNF-R2) in leprosy patients at different stages
of multidrug treatment (MDT) in comparison with non-infected individuals and to
determine their role as putative biomarkers of the severity of leprosy or the
treatment response. ELISA was used to measure the levels of these molecules in 30
healthy controls and 37 leprosy patients at the time of diagnosis and during and
after MDT. Our results showed increases in the serum levels of TNF-α and sTNF-R2 in
infected individuals in comparison with controls. The levels of TNF-α, but not
sTNF-R2, decreased with treatment. The current results corroborate previous reports
of elevated serum levels of TNF-α in leprosy and suggest a role for sTNF-R2 in the
control of this cytokine during MDT. 相似文献
67.
Yaping Kou Guohua Ma Jaime A. Teixeira da Silva Nian Liu 《Plant Cell, Tissue and Organ Culture》2013,112(1):1-7
Curcuma attenuata is a highly valued ornamental. This study provides the first report on C. attenuata shoot organogenesis and plant regeneration. Immature anthers derived from 5 to 7?cm long inflorescences were isolated and cultured on different variations of Murashige and Skoog (MS) media to induce callus and then shoot organogenesis. When the 2-mm long anthers in which microspores were at the uninucleate developmental stage were cultured in the dark on MS medium containing 13.6???M 2,4-dichlorophenoxyacetic acid (2,4-D) and 2.3???M kinetin (KT) for 15?days and then transferred to 40???mol?m?2?s?1 fluorescent light for 30?days, the percentage callus induction reached 33.3?%. After callus was transferred to various differentiation media and cultured in the light, 33.1?% of all callus cultures could differentiate into adventitious shoots on MS medium supplemented with 22.0???M 6-benzyladenine (BA), 0.53???M ??-naphthaleneacetic acid (NAA) and 1.4???M thidiazuron (TDZ) after culturing for 60?days. Over 95?% of plantlets survived after transplanting plantlets into trays with a mixture of sand and perlite (2: 1) for 20?days. Chromosome number, determined from the root tips of young plantlets, indicated that all plantlets were diploid (2n?=?84). 相似文献
68.
João Vidigal Mafalda M. Dias Fabiana Fernandes Marco Patrone Cláudia Bispo Cláudia Andrade Rui Gardner Manuel J.T. Carrondo Paula M. Alves Ana P. Teixeira 《Journal of biotechnology》2013
Insect cell lines such as Sf9 and High Five™ have been widely used to produce recombinant proteins mostly by the lytic baculovirus vector system. We have recently established an expression platform in Sf9 cells using a fluorescence-based recombinase mediated cassette exchange (RMCE) strategy which has similar development timelines but avoids baculovirus infection. To expedite cell engineering efforts, a robust fluorescence-activated cell sorting (FACS) protocol optimized for insect cells was developed here. The standard sorting conditions used for mammalian cells proved to be unsuitable, resulting in post-sorting viabilities below 10% for both cell lines. We found that the extreme sensitivity to the shear stress displayed by Sf9 and High Five™ cells was the limiting factor, and using Pluronic F-68 in the cell suspension could increase post-sorting viabilities in a dose dependent manner. The newly developed protocol was then used to sort stable populations of both cell lines tagged with a DsRed-expressing cassette. Before sorting, the average fluorescence intensity of the Sf9 cell population was 3-fold higher than that of the High Five™ cell population. By enriching with the 10% strongest DsRed-fluorescent cells, the productivity of both cell populations could be successfully improved. The established sorting protocol potentiates the use of RMCE technology for recombinant protein production in insect cells. 相似文献
69.
Bacterial community composition of anthropogenic biochar and Amazonian anthrosols assessed by 16S rRNA gene 454 pyrosequencing 总被引:1,自引:0,他引:1
Rodrigo Gouvêa Taketani Amanda Barbosa Lima Ederson da Conceição Jesus Wenceslau Geraldes Teixeira James M. Tiedje Siu Mui Tsai 《Antonie van Leeuwenhoek》2013,104(2):233-242
Biochar (BC) is a common minor constituent of soils and is usually derived from the burning of wood materials. In the case of Amazonian dark earth (ADE) soils, the increased amount of this material is believed to be due to anthropogenic action by ancient indigenous populations. In this study, we use 16S rRNA gene pyrosequencing to assess the bacterial diversity observed in the BC found in ADEs as well as in the dark earth itself and the adjacent Acrisol. Samples were taken from two sites, one cultivated with manioc and one with secondary forest cover. Analyses revealed that the community structure found in each sample had unique features. At a coarse phylogenetic resolution, the most abundant phyla in all sequence libraries were Actinobacteria, Acidobacteria, Verrucomicrobia and Proteobacteria that were present in similar relative abundance across all samples. However, the class composition varied between them highlighting the difference between the Acrisol and the remaining samples. This result was also corroborated by the comparison of the OTU composition (at 97 % identity). Also, soil coverage has shown an effect over the community structure observed in all samples. This pattern was found to be significant through unweighted UniFrac as well as P tests. These results indicate that, although the ADEs are found in patches within the Acrisols, the contrasting characteristics found between them led to the development of significantly different communities. 相似文献
70.
Alexandre Maller Tony Marcio da Silva André Ricardo de Lima Damásio Izaura Yoshico Hirata João Atílio Jorge Hector Francisco Terenzi Maria de Lourdes Teixeira de Moraes Polizeli 《Folia microbiologica》2013,58(6):615-621
A thermotolerant fungus identified as Aspergillus niveus was isolated from decomposing materials and it has produced excellent levels of hydrolytic enzymes that degrade plant cell walls. A. niveus germinated faster at 40 °C, presenting protein levels almost twofold higher than at 25 °C. The crude extract of the A. niveus culture was purified by diethylaminoethyl (DEAE)-cellulose, followed by Biogel P-100 column. Polygalacturonase (PG) is a glycoprotein with 37.7 % carbohydrate, molecular mass of 102.6 kDa, and isoelectric point of 5.4. The optimum temperature and pH were 50 °C and 4.0–6.5, respectively. The enzyme was stable at pH 3.0 to 9.0 for 24 h. The DEAE-cellulose derivative was about sixfold more stable at 60 °C than the free enzyme. Moreover, the monoaminoethyl-N-aminoethyl-agarose derivative was tenfold more stable than the free enzyme. PG was 232 % activated by Mn2+. The hydrolysis product of sodium polypectate corresponded at monogalacturonic acid, which classifies the enzyme as an exo-PG. The K m, V max, K cat, and K cat/K m values were 6.7 mg/ml, 230 U/mg, 393.3/s, and 58.7 mg/ml/s, respectively. The N-terminal amino acid sequence presented 80 % identity with PglB1, PglA2, and PglA3 putative exo-PG of Aspergillus fumigatus and an exo-PG Neosartorya fischeri. 相似文献