1,883 research outputs found

    Efficacy of instrumentation techniques and irrigation regimens in reducing the bacterial population within root canals

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    The purpose of this study was to compare the in vitro intracanal bacterial reduction produced by using two instrumentation techniques and different irrigation methods. Root canals inoculated with Enterococcus faecalis were prepared by using the following techniques and irrigants: alternated rotary motions (ARM) technique, hand nickel-titanium files and 2.5% sodium hypochlorite (NaOCl) as irrigant; ARM technique and combined irrigation with 2.5% NaOCl and citric acid; ARM technique and combined irrigation with 2.5% NaOCl and 2% chlorhexidine gluconate; and Greater Taper rotary files, using 2.5% NaOCl as irrigant. Controls were instrumented by using the ARM technique and irrigated with sterile saline. Canals were sampled before and after preparation. After serial dilution, samples were plated onto Mitis-Salivarius agar, and the colony forming units that were grown were counted. All test techniques and solutions significantly reduced the number of bacterial cells within the root canal (p 0.05). Nonetheless, all of them were significantly more effective than the control group (p < 0.05). These findings support the importance of using antimicrobial irrigants during the chemomechanical preparation, regardless of the solutions or instrumentation techniques used

    Asphalt binder "Skincare"? aging evaluation of an asphalt binder modified by Nano-TiO2

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    Aging by oxidation of asphalt roadway material promotes changes in its physical, chemical, and rheological properties, affecting its hardening and accelerating the degradation of its corresponding asphalt mixture. Titanium dioxide (TiO2) has been applied in engineering investigations to promote anti-aging and photocatalytic properties. In this study, a commercial binder was modified with nano-TiO2 (using contents of 0.1, 0.25, 0.5, 1, 2, 3, and 6%). It was evaluated by physicochemical and rheological tests (penetration, softening point, mass loss, dynamic viscosity, rheology, and Fourier transform infrared spectroscopy-FTIR) before and after aging by rolling thin-film oven test (RTFOT) and pressure aging vessel (PAV). The results indicated that incorporating nano-TiO2 mitigates binder aging, pointing out 0.25% as an optimum modification content for the investigated asphalt binder.This research was partially funded by the Portuguese Foundation for Science and Technology (FCT), PhD scholarship SFRH/BD/137421/2018, NanoAir PTDC/FISMAC/6606/2020, UIDB/04650/2020, and UIDB/04029/2020. V.C.B. would like to acknowledge National Council for Scientific and Technological Development (CNPq) for the funding on behalf of the scholarship 308360/2017-6. Furthermore, we would like to thank the Industrial Research Fund (IOF) for funding the PAPPoA project (IOF/SBO/41859/2020)

    Perspectives on the Trypanosoma cruzi-host cell receptor interaction

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    Chagas disease is caused by the parasite Trypanosoma cruzi. The critical initial event is the interaction of the trypomastigote form of the parasite with host receptors. This review highlights recent observations concerning these interactions. Some of the key receptors considered are those for thromboxane, bradykinin, and for the nerve growth factor TrKA. Other important receptors such as galectin-3, thrombospondin, and laminin are also discussed. Investigation into the molecular biology and cell biology of host receptors for T. cruzi may provide novel therapeutic targets

    Attenuation of motor deficits by hydroethanolic extract of Poincianella pyramidalis in a Parkinson's disease model

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    The present study aimed to evaluate the possible neuroprotective effect of the hydroethanolic extract of Poincianella pyramidalis (EFIPp) (Tul.) L. P. Queiroz (Fabaceae), an endemic plant found in Northeastern Brazil, commonly used in folk medicine, on the motor deficits induced by repeated treatment with reserpine (RES) in rats. Adult male Wistar rats received 10 s.c. injections of 0.1 mg/kg RES or vehicle (VR), every 48 h, and daily i.p. injections daily of HEPp (25 mg/kg) or vehicle (VE). Throughout treatment, catalepsy behavior and oral movements were scored. After behavioral tests, superoxide dismutase (SOD) and catalase (CAT) activities were evaluated in the prefrontal cortex, hippocampus and striatum. RES treatment induced a progressive increase of catalepsy time in the treated group compared to control groups starting at day 15. RES also increased the number of vacuous chewing movements, tongue protrusions and duration of facial twitching. Treatment with HEPp attenuated the motor deficit in the catalepsy test and delayed the onset of oral movements induced by RES. No significant changes were observed in the antioxidant assay. Taken together, these results show a beneficial effect of HEPp on motor deficits induced by reserpine, suggesting a neuroprotective effect in a rat model of PD.Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Fundação de Apoio a Pesquisa e a Inovação Tecnologica do Estado de Sergipe (FAPITEC)Pro-reitoria de Pesquisa da Universidade Federal de Sergipe (POSGRAP/UFS)Univ Fed Sergipe, Dept Physiol, Sao Cristovao, SE, BrazilUniv Massachusetts, Neurosci & Behav Program, Amherst, MA 01003 USAMinist Educ, CAPES Fdn, BR-70040020 Brasilia, DF, BrazilUniv Fed Sao Paulo, Dept Biosci, Santos, SP, BrazilUniv Fed Sao Paulo, Dept Pharmacol, Sao Paulo, SP, BrazilUniv Fed Sergipe, Dept Biosci, Itabaiana, SE, BrazilUniv Fed Sao Paulo, Dept Biosci, Santos, SP, BrazilUniv Fed Sao Paulo, Dept Pharmacol, Sao Paulo, SP, BrazilWeb of Scienc

    Identifying non-destructive growth and maturity indexes of Prickly pear (Opuntia albicarpa S. Var. Burrona) and evaluation of freeze-drying conditions

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    Around the world, prickly pear fruits are valued as a source of dietary functional compounds and ingredients for innovative foods. Growth and physicochemical changes of Opuntia albicarpa S. fruits were recorded from 0 to 132 days-after-flowering (DAF) to identify non-destructive maturity-indices. Optimum-ripened fruits were freeze-dried to study physicochemical and functional characteristics of dried and rehydrated pulp. Principal component analysis confirmed growth turned into fruit ripening in DAF 99, and it lasted until DAF 132. Changes in color parameters of the peel correlated with fruit texture and pulp sugar content and taste index (P < 0.01). During freeze-drying, plate temperature had more significant effects than the thickness (P < 0.05). At 30°C, color ΔE between dried and fresh slices augmented, but, texture Δ´s (medium force) between rehydrated and fresh pulp was lower. Color tests could be used to harvest commercially-ripened fruits. Freeze-drying at 30°C improves the rehydrated slices texture regarding thickness maintaining rehydration coefficients.Las tunas son apreciadas en todo el mundo como fuente de compuestos funcionales dietarios e ingredientes para alimentos innovadores. Para identificar índices de maduración no destructivos, se registraron cambios en el crecimiento y en los parámetros fisicoquímicos de frutos de Opuntia albicarpa S. entre los días después de la floración (DAF) 0 al 132. Frutos con maduración óptima fueron liofilizados para evaluar características fisicoquímicas y funcionales de pulpa seca y rehidratada. El análisis de componentes principales confirmo que el crecimiento dio lugar a la maduración en el DAF 99 y ésta prosiguió hasta el DAF 132. Los cambios en parámetros de color en cáscara correlacionaron con la textura del fruto, y en pulpa, con el contenido de azúcares y el índice de sabor (P< 0.01). Durante la liofilización, la temperatura de placa tiene más efectos significativos que el espesor (P≤ 0.05). A 30°C, el ΔE de color entre la pulpa seca y fresca aumentó, pero, el Δ de textura (fuerza media) fue menor entre la rehidratada y la fresca. Se pueden emplear evaluaciones de color para cosechar frutos en su madurez comercial, y liofilizar estos frutos a 30°C mejora la textura sin importar el espesor, manteniendo los coeficientes de rehidratación.This work was supported by the SIMORELOS program of CONACyT

    A“Dirty” Footprint: Macroinvertebrate diversity in Amazonian Anthropic Soils

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    International audienceAmazonian rainforests, once thought to be pristine wilderness, are increasingly known to have been widely inhabited, modified, and managed prior to European arrival, by human populations with diverse cultural backgrounds. Amazonian Dark Earths (ADEs) are fertile soils found throughout the Amazon Basin, created by pre-Columbian societies with sedentary habits. Much is known about the chemistry of these soils, yet their zoology has been neglected. Hence, we characterized soil fertility, macroinvertebrate communities, and their activity at nine archeological sites in three Amazonian regions in ADEs and adjacent reference soils under native forest (young and old) and agricultural systems. We found 673 morphospecies and, despite similar richness in ADEs (385 spp.) and reference soils (399 spp.), we identified a tenacious pre-Columbian footprint, with 49% of morphospecies found exclusively in ADEs. Termite and total macroinvertebrate abundance were higher in reference soils, while soil fertility and macroinvertebrate activity were higher in the ADEs, and associated with larger earthworm quantities and biomass. We show that ADE habitats have a unique pool of species, but that modern land use of ADEs decreases their populations, diversity, and contributions to soil functioning. These findings support the idea that humans created and sustained high-fertility ecosystems that persist today, altering biodiversity patterns in Amazonia

    Brazilian network for HIV Drug Resistance Surveillance (HIV-BresNet): a survey of treatment-naive individuals

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    Introduction: In Brazil, more than 487,450 individuals are currently undergoing antiretroviral treatment. In order to monitor the transmission of drug-resistant strains and HIV subtype distribution in the country, this work aimed to estimate its prevalence and to characterize the nationwide pretreatment drug resistance in individuals recently diagnosed with HIV between 2013 and 2015. Methods: The HIV threshold survey methodology (HIV-THS, WHO) targeting antiretroviral-naive individuals with recent HIV diagnosis was utilized, and subjects were selected from 51 highly populated cities in all five Brazilian macroregions. The HIV pol genotypic test was performed by genomic sequencing. Results: We analysed samples from 1568 antiretroviral-naive individuals recently diagnosed with HIV, and the overall transmitted drug resistance (TDR) prevalence was 9.5% (150 sequences). The regional prevalence of resistance according to Brazilian geographical regions was 9.4% in the northeast, 11.2% in the southeast, 6.8% in the central region, 10.2% in the north and 8.8% in the south. The inhibitor-specific TDR prevalence was 3.6% for nucleoside reverse transcriptase inhibitors (NRTIs), 5.8% for non-nucleoside reverse transcriptase inhibitors (NNRTIs) and 1.6% for protease inhibitors (PIs)1.0% of individuals presented resistance to more than one class of inhibitors. Overall, subtype B was more prevalent in every region except for the southern, where subtype C prevails. Conclusions: To the best of our knowledge, this is the first TDR study conducted in Brazil with nationwide representative sampling. The TDR prevalence revealed a moderate rate in the five Brazilian geographical regions, although some cities presented higher TDR prevalence rates, reaching 14% in Sao Paulo, for example. These results further illustrate the importance of surveillance studies for designing future strategies in primary antiretroviral therapy, aiming to mitigate TDR, as well as for predicting future trends in other regions of the globe where mass antiretroviral (ARV) treatment was implemented.Brazilian Ministry of HealthUniv Fed Rio de Janeiro, Lab Virol Mol, Dept Genet IB, Rio De Janeiro, RJ, BrazilFdn Med Trop Amazonas, Manaus, Amazonas, BrazilLAPI Univ Fed Bahia, Hosp Univ Prof Edgar Santos, Lab Pesquisa, Salvador, BA, BrazilLab Cent Saude Publ Ceara Lacen CE, Fortaleza, Ceara, BrazilLab Cent Saude Publ Dist Fed, Setor Grandes Areas Norte SGAN 601, Brasilia, DF, BrazilUniv Fed Minas Gerais UFMG, Fac Med, Lab Imunol & Biol Mol DIP, Belo Horizonte, MG, BrazilLab Cent Saude Publ Mato Grosso Sul, Campo Grande, MS, BrazilLab Cent Saude Publ Pernambuco, Recife, PE, BrazilLab Municipal Curitiba, Curitiba, PR, BrazilFiocruz MS, Lab AIDS & Imunol Mol, Dept Imunol, Rio De Janeiro, RJ, BrazilUniv Fed Rio de Janeiro, Hosp Univ Clementino Fraga Filho, Lab Carga Viral, Rio de Janeiro, RJ, BrazilInst Biol Exercito, Rio De Janeiro, RJ, BrazilLab Cent Saude Publ Rio Grande Sul, Porto Alegre, RS, BrazilLab Hosp Nossa Senhora Conceicao, Porto Alegre, RS, BrazilLab Cent Saude Publ Santa Catarina, Florianopolis, SC, BrazilUNESP, Lab Biol Mol Hemocentro Botucatu, Fac Med, Botucatu, SP, BrazilUniv Estadual Campinas, Lab Pesquisa AIDS, Hosp Clin, Campinas, SP, BrazilInst Adolfo Lutz Sao Jose do Rio Preto, Lab Biol Mol, Sao Jose Do Rio Preto, SP, BrazilUniv Fed Sao Paulo UNIFESP, Escola Paulista Med, Lab Retrovirol, Sao Paulo, SP, BrazilInst Adolfo Lutz Cent, Lab Retrovirus, Ctr Virol, Nucleo Doencas Sanguineas & Sexuais, Sao Paulo, SP, BrazilMinist Saude, Dept Vigilancia Prevencao & Controle DST AIDS & H, Setor Adm Fed Sul SAFS 02, Secretaria Vigilancia Saude, Brasilia, DF, BrazilUniv Brasilia, Programa Pos Grad Saude Colet, Fac Med, Fac Ciencias Saude, Brasilia, DF, BrazilUniv Sao Paulo, Fac Med, Sao Paulo, SP, BrazilUniv Fed Sao Paulo UNIFESP, Escola Paulista Med, Lab Retrovirol, Sao Paulo, SP, BrazilBMH: TC 298/12Web of Scienc

    Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis.

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    Multiple sclerosis is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability. Epidemiological studies have shown that genetic factors are primarily responsible for the substantially increased frequency of the disease seen in the relatives of affected individuals, and systematic attempts to identify linkage in multiplex families have confirmed that variation within the major histocompatibility complex (MHC) exerts the greatest individual effect on risk. Modestly powered genome-wide association studies (GWAS) have enabled more than 20 additional risk loci to be identified and have shown that multiple variants exerting modest individual effects have a key role in disease susceptibility. Most of the genetic architecture underlying susceptibility to the disease remains to be defined and is anticipated to require the analysis of sample sizes that are beyond the numbers currently available to individual research groups. In a collaborative GWAS involving 9,772 cases of European descent collected by 23 research groups working in 15 different countries, we have replicated almost all of the previously suggested associations and identified at least a further 29 novel susceptibility loci. Within the MHC we have refined the identity of the HLA-DRB1 risk alleles and confirmed that variation in the HLA-A gene underlies the independent protective effect attributable to the class I region. Immunologically relevant genes are significantly overrepresented among those mapping close to the identified loci and particularly implicate T-helper-cell differentiation in the pathogenesis of multiple sclerosis

    Machado-Joseph disease in a Nigerian family: mutational origin and review of the literature

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    Machado-Joseph disease (MJD) has been described in Africans, but no cases have been reported from Nigeria. Current MJD global distribution results from both the ancestral populations-of-origin and the founder effects of mutations, some as a consequence of the Portuguese sea travels in the 15th to 16th century. Two main ancestral haplotypes have been identified: the Machado lineage, which is more recent, predominant in families of Portuguese extraction, and the Joseph lineage, which is much older and worldwide spread, postulated to have an Asian origin. We report a Nigerian family with MJD from Calabar, once settled by Portuguese slave traders, and assessed its mutational origin. The proband was a 33-year-old man with progressive unsteady gait, weakness of all limbs, dysphagia, dysarthria, urinary frequency and diaphoresis. He had end-of-gaze nystagmus, spastic quadriparesis and atrophic small muscles of the hand. He showed fibrillation potentials on EMG, and nerve conduction studies suggested a central axonopathy without demyelination. This family bears the Joseph haplotype, which has a founder effect in the island of Flores, in the Azores (and their descendants in North-America), but is also the most common in non-Portuguese populations worldwide, with an estimated mutation age of around 7000 years.SM is the recipient of a scholarship (SFRH/BPD/77969/2011) from the Portuguese Foundation for Science and Technology (FCT); IPATIMUP is partially supported by FCT. This work was co-financed by the European Social Fund (Human Potential Thematic Operational Programme)
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