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991.
Renato R.R. Braga Maria Auxiliadora R. Carvalho Oscar Bruña-Romero Rodrigo E. Teixeira José Eustáquio Costa Edilberto N. Mendes Luiz M. Farias Paula P. Magalhães 《Anaerobe》2010,16(3):234-239
Chronic periodontitis is a highly prevalent endogenous polymicrobial disease. To better understand the etiology of the disease a quantitative approach is mandatory and real-time PCR is the molecular technique currently preferred to achieve this purpose. Taking into account that such a kind of study is still scarce, we aimed to evaluate the association between periodontal microbiota and chronic periodontitis. A total of 60 low-income age-matched female adults, 30 with chronic periodontitis and 30 without periodontal disease, were enrolled. DNA obtained from subgingival specimens was used for quantification of Aggregatibacter actinomycetemcomitans, Eikenella corrodens, Fusobacterium nucleatum, Porphyromonas gingivalis, and Prevotella intermedia by real-time PCR. A. actinomycetemcomitans, E. corrodens, and F. nucleatum were detected in all subjects, P. gingivalis was observed in 70.0% and 46.6% and P. intermedia in 90.0% and 80.0% of chronic periodontitis patients and periodontally healthy subjects, respectively. P. gingivalis mean count was significantly higher in patients with chronic periodontitis than in periodontally healthy individuals. Accurate detection and quantification of five putative periodontal pathogens was feasible using a simple and fast real-time PCR protocol. Although P. gingivalis and P. intermedia have been found more commonly in chronic periodontitis patients, no statistical difference was observed between periodontally diseased and healthy groups. Quantitative data indicated association between P. gingivalis and chronic periodontitis. However, because of its uneven distribution, it should not be solely taken as a marker of periodontal status. 相似文献
992.
Ana F. Soares Rui A. Carvalho Francisco J. Veiga John G. Jones 《Metabolic engineering》2010,12(6):552-560
Hepatic glycogen is formed by direct and indirect pathways whose activities reflect altered nutrition or disease. Direct/indirect pathway measurements often involve test meals where ~10% of carbohydrate is galactose, but its effects on direct/indirect pathway estimates are unknown. Therefore, direct/indirect pathway contributions in 24-h fasted rats given 2 g/kg 100% glucose (GLU, n=6) or 90% glucose–10% galactose (GLU+GAL, n=6) were measured by [U-13C]glucose dilution and by position-5/position-2 glycogen enrichment (H5/H2) from 2H2O. For GLU+GAL, galactose glycogenesis was independently measured with [1-13C]galactose. Glycogenesis was equivalent in both groups but for GLU+GAL, 23±4% of glycogen was derived from galactose. [U-13C]glucose reported a 30±3% direct pathway contribution to glycogenesis for GLU but only 20±3% for GLU+GAL (p=0.012 vs. GLU). H5/H2 yielded identical direct pathway estimates (32±3% GLU, 29±6% GLU+GAL). Thus, galactose glycogenesis was undetected by H5/H2 while [U-13C]glucose reported a reduced direct/indirect pathway ratio. With [1-13C]galactose also present, correct glycogenic source contributions were obtained. 相似文献
993.
Michele Rigon Spier Adenise Lorenci Woiciechowski Luiz Alberto Junior Letti Gessiel Newton Scheidt Wilerson Sturm Jose Angel Rodriguez-León Julio César de Carvalho Dario Eduardo Amaral Dergint Carlos Ricardo Soccol 《Bioprocess and biosystems engineering》2010,33(9):1033-1041
Fermentation parameters for phytase production in column-type bioreactor were monitored using a new data acquisition system. There are a number of studies reporting phytase production in flasks, but a lack of data about microorganism respiration behaviour during phytase production using column bioreactor. The objectives of this work were the monitoration of fermentation parameters during phytase production and its relation with fungal growth and forced air. Phytase production by A. niger FS3 increased with forced air. The O2 consumption and CO2 production during solid-state fermentation were monitored by sensors (in the bottom and top of the columns) linked to controllers, recorded by acquisition software and processed by Fersol2® software tool. Phytase synthesis was associated with fungal growth. Therefore, phytase could be used to estimate FS3 biomass formed in citric pulp degradation. 相似文献
994.
Emiret O. Faria Lucilia Kato Cecília M.A. de Oliveira Brenda G. Carvalho Cleuza C. Silva Lilian S. Sales Ivânia T.A. Schuquel Elisângela P. Silveira-Lacerda Piero G. Delprete 《Phytochemistry letters》2010,3(3):113-116
Two new quaternary alkaloids, compound 1 and the 14-oxo derivative 2, were isolated along with the known alkaloid strictosamide (3) from the leaves of Psychotria prunifolia (Kunth) Steyerm. (Rubiaceae, Psychotriae). Their structures were elucidated using spectroscopic methods (1D and 2D NMR, IR, and HRMS). 相似文献
995.
Flavia M. Carvalho Eduardo M. B. Tinoco Kathleen Deeley Poliana M. Duarte Marcelo Faveri Marcelo R. Marques Adriana C. Mendon?a Xiaojing Wang Karen Cuenco Renato Menezes Gustavo P. Garlet Alexandre R. Vieira 《PloS one》2010,5(4)
Aggressive periodontitis is characterized by a rapid and severe periodontal destruction in young systemically healthy subjects. A greater prevalence is reported in Africans and African descendent groups than in Caucasians and Hispanics. We first fine mapped the interval 1q24.2 to 1q31.3 suggested as containing an aggressive periodontitis locus. Three hundred and eighty-nine subjects from 55 pedigrees were studied. Saliva samples were collected from all subjects, and DNA was extracted. Twenty-one single nucleotide polymorphisms were selected and analyzed by standard polymerase chain reaction using TaqMan chemistry. Non-parametric linkage and transmission distortion analyses were performed. Although linkage results were negative, statistically significant association between two markers, rs1935881 and rs1342913, in the FAM5C gene and aggressive periodontitis (p = 0.03) was found. Haplotype analysis showed an association between aggressive periodontitis and the haplotype A-G (rs1935881-rs1342913; p = 0.009). Sequence analysis of FAM5C coding regions did not disclose any mutations, but two variants in conserved intronic regions of FAM5C, rs57694932 and rs10494634, were found. However, these two variants are not associated with aggressive periodontitis. Secondly, we investigated the pattern of FAM5C expression in aggressive periodontitis lesions and its possible correlations with inflammatory/immunological factors and pathogens commonly associated with periodontal diseases. FAM5C mRNA expression was significantly higher in diseased versus healthy sites, and was found to be correlated to the IL-1β, IL-17A, IL-4 and RANKL mRNA levels. No correlations were found between FAM5C levels and the presence and load of red complex periodontopathogens or Aggregatibacter actinomycetemcomitans. This study provides evidence that FAM5C contributes to aggressive periodontitis. 相似文献
996.
Isabela Werneck Cunha Katia Candido Carvalho Waleska Keller Martins Sarah Martins Marques Nair Hideko Muto Roberto Falzoni Rafael Malagoli Rocha Samuel Aguiar Ana C.Q. Simoes Lucas Fahham Eduardo Jordão Neves Fernando Augusto Soares Luiz Fernando Lima Reis 《Translational oncology》2010,3(1):23-32
Soft tissue tumors represent a group of neoplasia with different histologic and biological presentations varying from benign, locally confined to very aggressive and metastatic tumors. The molecular mechanisms responsible for such differences are still unknown. The understanding of these molecular alterations mechanism will be critical to discriminate patients who need systemic treatment from those that can be treated only locally and could also guide the development of new drugs'' against this tumors. Using 102 tumor samples representing a large spectrum of these tumors, we performed expression profiling and defined differentially expression genes that are likely to be involved in tumors that are locally aggressive and in tumors with metastatic potential. We described a set of 12 genes (SNRPD3, MEGF9, SPTAN-1, AFAP1L2, ENDOD1, SERPIN5, ZWINTAS, TOP2A, UBE2C, ABCF1, MCM2, and ARL6IP5) showing opposite expression when these two conditions were compared. These genes are mainly related to cell-cell and cell-extracellular matrix interactions and cell proliferation and might represent helpful tools for a more precise classification and diagnosis as well as potential drug targets. 相似文献
997.
Elias César Araujo de Carvalho Adelia Portero Batilana Julie Simkins Henrique Martins Jatin Shah Dimple Rajgor Anand Shah Scott Rockart Ricardo Pietrobon 《PloS one》2010,5(2)
Background
Sharing of epidemiological and clinical data sets among researchers is poor at best, in detriment of science and community at large. The purpose of this paper is therefore to (1) describe a novel Web application designed to share information on study data sets focusing on epidemiological clinical research in a collaborative environment and (2) create a policy model placing this collaborative environment into the current scientific social context.Methodology
The Database of Databases application was developed based on feedback from epidemiologists and clinical researchers requiring a Web-based platform that would allow for sharing of information about epidemiological and clinical study data sets in a collaborative environment. This platform should ensure that researchers can modify the information. A Model-based predictions of number of publications and funding resulting from combinations of different policy implementation strategies (for metadata and data sharing) were generated using System Dynamics modeling.Principal Findings
The application allows researchers to easily upload information about clinical study data sets, which is searchable and modifiable by other users in a wiki environment. All modifications are filtered by the database principal investigator in order to maintain quality control. The application has been extensively tested and currently contains 130 clinical study data sets from the United States, Australia, China and Singapore. Model results indicated that any policy implementation would be better than the current strategy, that metadata sharing is better than data-sharing, and that combined policies achieve the best results in terms of publications.Conclusions
Based on our empirical observations and resulting model, the social network environment surrounding the application can assist epidemiologists and clinical researchers contribute and search for metadata in a collaborative environment, thus potentially facilitating collaboration efforts among research communities distributed around the globe. 相似文献998.
Fernanda Martins Tatiana M. Noso Viviane B. Porto Alline Curiel Alessandra Gambero Deborah H.M. Bastos Marcelo L. Ribeiro Patrícia de O. Carvalho 《Obesity (Silver Spring, Md.)》2010,18(1):42-47
The inhibitory effects of maté tea (MT), a beverage produced with leaves from Ilex paraguariensis, in vitro lipase activity and on obesity in obese mice models were examined. For the in vitro experiment, porcine and human pancreatic lipase (PL) activities were determined by measuring the rate of release of oleic acid from hydrolysis of olive oil emulsified with taurocholate, phospholipids, gum arabic, or polyvinyl alcohol. For the in vivo experiments, animals were fed with a standard diet (SD, n = 10) or high‐fat diet (HFD, n = 30) for 16 weeks. After the first 8 weeks on the HFD, the animals were treated with 1 and 2 g/kg of body weight of MT. The time course of the body weight and obesity‐related biochemical parameters were evaluated. The results showed that MT inhibited both porcine and human PL (half‐maximal inhibitory concentration = 1.5 mg MT/ml) and induced a strong inhibition of the porcine lipase activity in the hydrolysis of substrate emulsified with taurocholate + phosphatidylcholine (PC) (83 ± 3.8%) or PC alone (62 ± 4.3%). MT suppressed the increases in body weight (P < 0.05) and decreased the serum triglycerides and low‐density lipoprotein (LDL)‐cholesterol concentrations at both doses (from 190.3 ± 5.7 to 135.0 ± 8.9 mg/dl, from 189.1 ± 7.3 to 129.3 ± 17.6 mg/dl; P < 0.05, respectively) after they had been increased by the HFD. The liver lipid content was also decreased by the diet containing MT (from 132.6 ± 3.9 to 95.6 ± 6.1 mg/g of tissue; P < 0.05). These results suggest that MT could be a potentially therapeutic alternative in the treatment of obesity caused by a HFD. 相似文献
999.
L. Pinto P. Poeta S. Vieira C. Caleja H. Radhouani C. Carvalho M. Vieira-Pinto P. Themudo C. Torres R. Vitorino P. Domingues G. Igrejas 《Journal of Proteomics》2010,73(8):1535-1541
Using Salmonella strains identical to those present in the gastrointestinal tract of different animals we aim to determine and compare the proteome of two serotypes, Salmonella Typhimurium and Enteritidis recovered from faecal samples of wild boars and wild rabbits, respectively. The presence of genes responsible for antibiotic resistance was detected by PCR. Proteomes of the two distinct serotypes were determined using 2-DE in order to identify proteins associated with antibiotic resistance or virulence. Through 2-DE we obtained a total of 229 spots from both strains. All were suitable for MALDI-TOF/TOF and, in correlation with bioinformatic databases, allowed accurate identification and characterization of proteins. S. Enteritidis recovered from wild rabbits was sensitive to all the antibiotics tested in contrast to S. Typhimurium isolated from wild boars which presented a resistance phenotype to ampicillin, streptomycin and chloramphenicol. Nevertheless, despite the different ratio of proteins observed in each proteome according to their biological function, no significant difference was observed in the involvement of these proteins in pathogenicity. Bearing in mind that serotypes are related to infectious processes in humans and animals, it is important to explore the proteome of new strains which might serve as protein biomarkers for biological activity. 相似文献
1000.
Mass spectrometry-based proteomics is rapidly becoming an essential tool for biologists. One of the most common applications is identifying the components of protein complexes isolated by co-immunoprecipitation. In this review, we discuss the co-immunoprecipitation, mass spectrometry and data analysis techniques that have been used successfully to define protein complexes in C. elegans research. In this discussion, two strategies emerged. One approach is to use stringent biochemical purification methods and attempt to identify a small number of complex components with a high degree of certainty based on MS data. A second approach is to use less stringent purification and identification parameters, and ultimately test a longer list of potential binding partners in biological validation assays. This should provide a useful guide for biologists planning proteomic experiments. 相似文献