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61.
Nat lia Oliveira e Silva Breno Bittencourt de Brito Filipe Ant nio Fran a da Silva Maria Lu sa Cordeiro Santos Fabr cio Freire de Melo 《World Journal of Meta-Analysis》2020,8(2):54-66
The number of patients with inflammatory bowel disease (IBD), a group of diseases mainly represented by Crohn’s disease (CD) and ulcerative colitis (UC), has increased in recent decades. As a consequence, the number of people undergoing any drug treatment against these diseases has expanded. However, IBD conventional therapies present several limitations, which lead researchers to look for better alternatives to improve the quality of life of patients. Moreover, microbiome imbalance seems to play a crucial role in the pathogenesis of IBD, since important alterations in bacterial, viral, protist and fungal populations are observed in the gut microbiota of affected individuals. Given the importance of such life forms in that context, the use of probiotics becomes a plausible alternative for treating affected patients. Trials have been developed aiming the evaluation of probiotics potential to induce and to maintain remission in CD and UC. Regarding the tested microorganisms, various non-pathogenic bacteria and fungi have been assessed. However, consistent results have been obtained only with some of them, including Escherichia coli Nissle 1917, VSL#3, Saccharomyces boulardii, Lactobacillus, and Bifidobacterium. Therefore, this minireview aims to explore the role of microbiota in the genesis of such a disorder and to compile the most concrete data on probiotic-related efficiency in IBD treatment. 相似文献
62.
Juliana Maier Camila Silveira Sfreddo Ana Paula Pereira Reiniger Karla Zanini Kantorski Ulf ME Wikesj Carlos Heitor Cunha Moreira 《International dental journal》2021,71(2):127
BackgroundPeriodontal disease is a major cause of tooth loss. Few studies have evaluated the residual area of the periodontal ligament in extracted teeth and, to the best of our knowledge, none from Latin America have done so regarding indications for extraction. The aim of this study was to evaluate the residual periodontal ligament (RPL) with respect to indication for extraction in a sample of teeth from a Brazilian Public Health Service district.Materials and methodsAll teeth extracted within the Public Health Service district of Santa Maria, Brazil, over a 5-month period were requested for analysis. A total of 414 teeth eligible for measurement were stained and evaluated for RPL using a stereo microscope. Participating Public Health Service dentists completed a questionnaire detailing demographic variables and indication for each extracted tooth. The percentage of RPL was determined for each tooth. Comparisons of RPL between teeth extracted on periodontal versus other indications were made using the Mann-Whitney test.ResultsRPL averaged 34.8% for teeth extracted on periodontal indications versus 79.5% for other teeth (P ≤ 0.001). When considering teeth with an RPL ≥ 30% as possible to maintain, 189 (76%) of the teeth extracted on periodontal indications could have been maintained. When RPL cut-off limits of ≥ 40% or ≥ 50% are applied, 93 (37%) and 43 (17%) teeth, respectively, could have been maintained.ConclusionThis study suggests that strictly based on RPL, a large number of teeth extracted on periodontal indications conceivably could be maintained.Key words: Cross-sectional studies, Prognosis, Tooth extraction, Tooth loss 相似文献
63.
G. El Fidha N. Bitri F. Chaabouni S. Acosta F. Güell C. Bittencourt J. Casanova-Chafer E. Llobet 《RSC advances》2021,11(40):24917
Dysprosium-doped zinc oxide (ZnO) thin films have been prepared through spray pyrolysis onto glass substrates. Cross-sections of the deposited thin films were assessed through Scanning Electron Microscopy (SEM), showing thicknesses between 200 and 300 nm. The thin film roughness was evaluated using the obtained images from the Atomic Force Microscope (AFM) micrographs. The crystallographic structure of the samples was analyzed by X-ray diffraction (XRD) revealing polycrystalline thin films. However, the slight shift towards a higher 2θ angle in Dy-doped ZnO films as compared to the pure ones indicates the incorporation of Dy3+ into the ZnO crystal lattice. The analysis of the oxidation state via X-ray photoelectron spectroscopy (XPS) confirms the incorporation of Dy ions in the ZnO matrix. Besides, UV-Vis-NIR spectrophotometry analysis and photoluminescence (PL) spectroscopy showed that bandgap energy values of ZnO decreased when dysprosium doping increased. Therefore, Dy doped ZnO thin films can be potentially used as a solar-light-driven photocatalyst. Among the different doping yields, the ZnO doped with 6% dysprosium provides the highest degradation rate for methylene blue (MB) under solar irradiation. Specifically, 9% of dye degradation was achieved under sunlight irradiation for 120 minutes.Dysprosium-doped zinc oxide (ZnO) thin films prepared through spray pyrolysis show outstanding photocatalytic activity for the degradation of methylene blue. 相似文献
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65.
Giovanne B. Diniz Daniella S. Battagello Marianne O. Klein Bianca S. M. Bono Jozélia G. P. Ferreira Livia C. Motta-Teixeira Jessica C. G. Duarte Françoise Presse Jean-Louis Nahon Antoine Adamantidis Melissa J. Chee Luciane V. Sita Jackson C. Bittencourt 《Journal of neuroscience research》2020,98(10):2045-2071
Melanin-concentrating hormone (MCH) is a ubiquitous vertebrate neuropeptide predominantly synthesized by neurons of the diencephalon that can act through two G protein-coupled receptors, called MCHR1 and MCHR2. The expression of Mchr1 has been investigated in both rats and mice, but its synthesis remains poorly described. After identifying an antibody that detects MCHR1 with high specificity, we employed immunohistochemistry to map the distribution of MCHR1 in the CNS of rats and mice. Multiple neurochemical markers were also employed to characterize some of the neuronal populations that synthesize MCHR1. Our results show that MCHR1 is abundantly found in a subcellular structure called the primary cilium, which has been associated, among other functions, with the detection of free neurochemical messengers present in the extracellular space. Ciliary MCHR1 was found in a wide range of areas, including the olfactory bulb, cortical mantle, striatum, hippocampal formation, amygdala, midline thalamic nuclei, periventricular hypothalamic nuclei, midbrain areas, and in the spinal cord. No differences were observed between male and female mice, and interspecies differences were found in the caudate-putamen nucleus and the subgranular zone. Ciliary MCHR1 was found in close association with several neurochemical markers, including tyrosine hydroxylase, calretinin, kisspeptin, estrogen receptor, oxytocin, vasopressin, and corticotropin-releasing factor. Given the role of neuronal primary cilia in sensing free neurochemical messengers in the extracellular fluid, the widespread distribution of ciliary MCHR1, and the diverse neurochemical populations who synthesize MCHR1, our data indicate that nonsynaptic communication plays a prominent role in the normal function of the MCH system. 相似文献
66.
Itamar S. Santos Márcio S. Bittencourt Ilka R.S. Oliveira Angelita G. Souza Danilo P. Meireles Tatjana Rundek Murilo Foppa Daniel C. Bezerra Cláudia M.V. Freire Leonard H. Roelke Sayonara Carrilho Isabela M. Benseñor Paulo A. Lotufo 《Atherosclerosis》2014
Objective
Carotid intima–media thickness (IMT) is a noninvasive measurement of early atherosclerosis. Most IMT studies have involved populations with low rates of racial blending. The aim of the present article is to describe IMT value distributions and analyze the influence of sex and race on IMT values in a large Brazilian sample, a setting with a high rate of racial admixture.Methods
The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) is a multicenter cohort of 15,105 adult (aged 35–74 years) civil servants in six Brazilian cities. Baseline assessment included IMT measurements in both common carotid arteries. Race was self-reported. We studied the association between sex and race with IMT values using multiple linear regression models. We conducted analyses in all and low-risk individuals, defined as those without classical cardiovascular risk factors.Results
We analyzed complete IMT data from 10,405 ELSA-Brasil participants. We present nomograms by age for all and low-risk individuals, stratified by sex and race. We found that men had significantly higher maximal IMT values compared with women (β = 0.058; P < 0.001). This association remained for low-risk individuals (β = 0.027; P = 0.001). In addition, Brown and White individuals had lower maximal IMT values compared with Black individuals for all (β = −0.034 and β = −0.054, respectively; P < 0.001) and low-risk individuals (β = −0.027; P = 0.013 and β = −0.035; P < 0.001, respectively).Conclusion
We found significantly higher IMT values in men. We found significantly higher IMT values in Black individuals than White and Brown individuals. These results persisted when analyses were restricted to low-risk individuals. 相似文献67.
C. Schmidt M. Fronza M. Goettert F. Geller S. Luik E.M.M. Flores C.F. Bittencourt G.D. Zanetti B.M. Heinzmann S. Laufer I. Merfort 《Journal of ethnopharmacology》2009
Aim of the study
n-Hexanic and ethanolic extracts from twelve plants (Brugmansia suaveolens Brecht. et Presl., Eupatorium laevigatum Lam., Galinsoga parviflora Cav., Iresine herbstii Hook., Kalanchöe tubiflora Hamet-Ahti, Petiveria alliacea L., Pluchea sagittalis (Lam.) Cabrera, Piper regnellii DC., Schinus molle L., Sedum dendroideum Moç et Sessé ex DC., Waltheria douradinha St. Hill., Xanthium cavanillesii Schouw.) used in traditional South Brazilian medicine as wound healing agents were investigated in various biological assays, targeting different aspects in this complex process.Materials and methods
The extracts were investigated on NF-κB DNA binding, p38α MAPK, TNF-α release, direct elastase inhibition and its release as well as on caspase-3. Fibroblasts migration to and proliferation into the wounded monolayers were evaluated in the scratch assay, the agar diffusion test for antibacterial and the MTT assay for cytotoxic effects.Results
The hydrophilic extracts from Galinsoga parviflora, Petiveria alliacea, Schinus molle, Waltheria douradinha and Xanthium cavanillesii as well as the lipophilic extract of Waltheria douradinha turned out to be the most active ones.Conclusions
These results increase our knowledge on the wound healing effects of the investigated medicinal plants. Further studies are necessary to find out the effective secondary metabolites responsible for the observed effects. 相似文献68.
Anne Caroline Schoch Marques Pinto Camilla Reginatto De Pierri Alberto Gonalves Evangelista Ana Silvia de Lara Pires Batista Gomes Fernando Bittencourt Luciano 《Toxins》2022,14(2)
Deoxynivalenol (DON) is a toxic secondary metabolite produced by fungi that contaminates many crops, mainly wheat, maize, and barley. It affects animal health, causing intestinal barrier impairment and immunostimulatory effect in low doses and emesis, reduction in feed conversion rate, and immunosuppression in high doses. As it is very hard to completely avoid DON’s production in the field, mitigatory methods have been developed. Biodegradation has become a promising method as new microorganisms are studied and new enzymatic routes are described. Understanding the common root of bacteria with DON degradation capability and the relationship with their place of isolation may bring insights for more effective ways to find DON-degrading microorganisms. The purpose of this review is to bring an overview of the occurrence, regulation, metabolism, and toxicology of DON as addressed in recent publications focusing on animal production, as well as to explore the enzymatic routes described for DON’s degradation by microorganisms and the phylogenetic relationship among them. 相似文献
69.
Maria Irma Seixas Duarte Heitor Franco de Andrade Cleusa Fumica Hirata Takamura Antonio Sesso Felipe Francisco Tuon 《Parasitology research》2009,104(5):1129-1136
The liver involvement in the human visceral leishmaniasis (VL) has been related to parasitism and activated Kupffer cells
with further occasional fibrotic alterations, especially after long-term disease without treatment. However, fibrotic alterations
have been reported after therapy, whose clinical finding is the persistence of hepatomegaly. Fibrotic involvement of the liver
after therapy was never well understood, and the aim of this study was to evaluate this finding through ultrastructural and
morphometric analysis. A case–control study was performed with 20 patients (15 cases and five controls). Cases included patients
with persistent hepatomegaly (residual) after treatment of VL submitted to liver biopsy to exclude other causes of liver enlargement,
including serum tests of viral hepatitis. The material was evaluated by electron microcopy allowing ultrastructural with morphometric
analysis of medium portion of hepatic lobule. Narrow sinusoidal lumen and prominent Kupffer cells were found with insignificant
alterations of hepatocytes, pit, and endothelial cells. On ultrastructural analysis, the enlargement of the space of Disse
was due to fibrous collagen, increase of number of Ito cells, and nonfibrous extracellular matrix that were associated with
Kupffer cells enlargement. Immunohistochemistry showed an intense expression of TGF-beta in patients with VL. These findings
suggest a production of TGF-beta by Kupffer cells that resulted in the characteristic fibrotic involvement of the liver. Residual
hepatomegaly in visceral leishmaniasis could result from sustained Kupffer cell activation with perihepatocytic fibrosis.
The authors are not part of any associations or commercial relationships that might represent conflicts of interest in the
writing of this study (e.g., pharmaceutical stock ownership, consultancy, advisory board membership, relevant patents, or
research funding). This article has financial support by the FAPESP (Grants 96/5875-8) 相似文献
70.