997 resultados para Simulator of Human Intestinal Microbial Ecosystem (SHIME)


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The formation of salivary glands entails the proliferation of epithelial cells from the stomatodeum into the underlying ectomesenchyme, culminating in a complex network of ducts and acinar bulbs. The extent to which mucins regulate this process is unknown, but they appear to mediate luminal space formation and maturation. Our aim was to examine mucin expression patterns during the morphogenesis of human salivary glands. Mucin expression - MUC1, 2, 3, 4, 5AC, 5B, 6, and 16 - was analyzed in specimens of developing human salivary glands, obtained from fetuses at 4-24 weeks` gestation, and fully developed salivary glands by immunohistochemistry. Expression patterns were analyzed qualitatively according to the development stage of the salivary glands. Mucins 1, 3, 4, 5B, and 16 were expressed during salivary gland development - being stronger in all ductal segments by the final phases of branching morphogenesis and in mature glands. Acinar cells were negative for most mucins, including MUC1 in mature salivary glands. Mucins 2, 5AC, and 6 were not expressed. Mucins MUC1, 3, 4, 5B, and 16 are expressed in developing human salivary glands and in mature glands, suggesting important roles in the maturation and maintenance of the ductal network.

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Objective: Human T-cell lymphotropic virus type 1 (HTLV-1) was the first human retrovirus discovered and its pathogenesis is related to T cells infection. This study aimed to verify the presence of oral manifestations in a Brazilian population of patients who was seropositive for HTLV, and identify risk factors for oral manifestations. Subjects and methods: An assessment was made of 139 patients at the Emilio Ribas Institute of Infectious Diseases. Results: A total of 112 (80.5%) patients were HTLV-1, 26 (18.7%) were HTLV-2+. About 35.2% of patients had myelopathy/tropical spastic paraparesis (HAM/TSP), with 48 of them being HTLV-1+ and one patient was seropositive for HTLV-1 and -2. The most common oral manifestations were: xerostomia (26.8%), candidiasis (20.8%), fissured tongue (17.9%), and loss of tongue papillae (10.0%). A multivariate logistic regression analysis showed that HAM/TSP is an independent risk factor for xerostomia (P = 0.02). The patients who were HAM/TSP+ were three times more likely to develop xerostomia when compared with patients without HAM/TSP (odds ratio = 2.69, 95% confidence interval = 1.17-6.17). Conclusion: Despite the fact that the findings of this study suggest a relationship between xerostomia and HAM/TSP, more studies should be developed to show what the association would be between xerostomia presented by HTLV patients and pathogenesis of the virus.

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Objectives: To compare the response of human dental pulp capped with a mineral trioxide aggregate (MTA) and Ca(OH)(2) powder. Methods and Material: Pulp exposures were performed on the occlusal floor of 40 permanent premolars. The pulp was then capped with either Ca(OH)(2) powder (CH) or MTA and restored with resin composite. After 30 days (groups CH30 and MTA30) and 60 days (groups CH60 and MTA60), the teeth were extracted and processed for HE and categorized in a histological score system. The data were subjected to Kruskal-Wallis and Conover tests (alpha=0.05). Results: In regard to dentin bridge formation, CH30 showed a tendency towards superior performance compared to MTA30 (p>0.05), although the products showed comparable results at day 60. In the item ""Inflammation"" and ""General State of the Pulp"" (p>0.05), CH showed a tendency towards presenting a higher inflammatory response. In the item ""Other Pulpal Findings,"" MTA and Ca(OH)(2) showed equal and excellent performance after 30 and 60 days (p>0.05). Conclusion: After 30 days, Ca(OH)(2) powder covered with calcium hydroxide cement showed faster hard tissue bridge formation compared to MTA. After 60 days, Ca(OH)(2) powder or NITA materials showed a similar and excellent histological response with the formation of a hard tissue bridge in almost all cases with low inflammatory infiltrate.

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The purpose of this in vitro study was to evaluate alterations in the surface roughness and micromorphology of human enamel submitted to three prophylaxis methods. Sixty-nine caries-free molars with exposed labial surfaces were divided into three groups. Group I was treated with a rotary instrument set at a low speed, rubber clip and a mixture of water and pumice; group II with a rotary instrument set at a low speed, rubber cup and prophylaxis paste Herjos-F (Vigodent S/A Industria e Comercio, Rio de Janeiro, Brazil); and group III with sodium bicarbonate spray Profi II Ceramic (Dabi A dante Indtistrias Medico Odontologicas Ltda, Ribeirao Preto, Brazil). All procedures were performed by the same operator for 10 s, and samples were rinsed and stored in distilled water. Pre and post-treatment surface evaluation was completed using a surface profilometer (Perthometer S8P Marh, Perthen, Germany) in 54 samples. In addition, the other samples were coated with gold and examined in a scanning electron microscope (SEM). The results of this study were statistically analyzed with the paired t-test (Student), the Kruskal-Wallis test and the Dunn (5%) test. The sodium bicarbonate spray led to significantly rougher surfaces than the pumice paste. The use of prophylaxis paste showed no statistically significant difference when compared with the other methods. Based on SEM analysis, the sodium bicarbonate spray presented an irregular surface with granular material and erosions. Based on this study, it can be concluded that there was an increased enamel stuface roughness when teeth were treated with sodium bicarbonate spray when compared with teeth treated with pumice paste.

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This in situ study evaluated the interaction between caries and erosion processes. In the first phase, enamel specimens were subjected to erosion without dental plaque (EO) or to erosion with plaque (EP); in the second phase, they were subjected to erosion plus cariogenic challenge (EC) or cariogenic challenge (CO), both with plaque accumulation. Cross-sectional hardness data (10-330 mu m depth) were tested using ANOVA (alpha = 0.05). EO and EP showed surface softening to 10 mu m depth. CO and EC produced subsurface lesions, of similar depth (up to 220 mu m), with CO showing higher integrated loss of hardness than EC, indicating that cariogenic and erosive challenges did not have an additive effect. Copyright (C) 2010 S. Karger AG, Basel

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Periodontitis is an infectious disease, where putative periodontopathogens trigger chronic inflammatory and immune responses against periodontal structures, in which an unbalanced host response is also determinant to the disease outcome. It is reasonable to assume that patient susceptibility to periodontal tissue destruction could be determined by the balance between the response against periodontopathogens and regulatory mechanisms of these events mediated by suppressive T cells. In the present study, we identified and characterized natural regulatory T cells ( Tregs) in the inflammatory infiltrate of human chronic periodontitis ( CP) with emphasis on phenotypic analyses that were carried out to address the participation of Tregs in CP. Results showed that patients with CP presented increased frequency of T lymphocytes and CD4(+)CD25(+) T cells in the inflammatory infiltrate of gingival tissues. These cells exhibited the phenotypic markers of Tregs such as forkhead box p3 ( Foxp3), CTLA- 4, glucocorticoidinducible TNFR, CD103, and CD45RO and seemed to be attracted to the inflammation site by the chemokines CCL17 and CCL22, as their expression and its receptor CCR4 were increased in CP patients. Moreover, besides the increased detection of Foxp3 mRNA, diseased tissues presented high expression of the regulatory cytokines IL-10 and TGF-beta. In addition, the inflammatory infiltrate in CP biopsies was composed of CD25(+)Foxp3(+) and CD25(+)TGF-beta(+) cells, thus corroborating the hypothesis of the involvement of Tregs in the pathogenesis of CP. Finally, these results indicate that Tregs are found in the chronic lesions and must be involved in the modulation of local immune response in CP patients.

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Background: Detection and quantification of human papillomavirus (HPV) may help in predicting the evolution of HPV infection and progression of associated lesions. Objectives: We propose a novel protocol using consensus primers GP5+/6+ in a SYBR Green quantitative real-time (Q-RT) polymerase chain reaction (PCR). The strategy permits screening for HPV infection and viral load quantification simultaneously. Study design: DNA from 153 archived cervical samples, previously tested for HPV detection by GP5+/6+ PCR and typed by EIA-RLB (enzyme immunoassay-reverse line blot) or sequence analysis, was analysed using SYBR Green Q-RT PCR. Melting temperature assay (T(m)) and cycle threshold (C(t)) were used to evaluate HPV positivity and viral load. The T(m) in the range of 77-82 degrees C was considered to be positive for HPV-DNA. HPV results generated through GP5+/6+ conventional PCR were considered the gold standard against which sensitivity and specificity of our assay were measured. Results: Out of 104 HPV positive samples, 100 (96.2%) were also determined as positive by SYBR Green Q-RT PCR; of the 49 HPV-negative samples, all were determined as negative. There was an excellent positivity agreement (K = 0.94) between the SYBR Green Q-RT and the previous methods employed. The specificity and sensitivity were 100% and 96.2%, respectively. Comparison of SYBR Green Q-RT and TaqMan oligo-probe technologies gave an excellent concordance (pc = 0.95) which validated the proposed strategy. Conclusions: We propose a sensitive and easy-to-perform technique for HPV screening and viral load quantification simultaneously. (C) 2009 Elsevier B.V. All rights reserved.

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Objective This study compared the clinical and radiographic effectiveness of mineral trioxide aggregate (MTA) and Portland cement (PC) as pulp dressing agents in carious primary teeth. Methodology Thirty carious primary mandibular molars of children aged 5-9 years old were randomly assigned to MTA or PC groups, and treated by a conventional pulpotomy technique. The teeth were restored with resin modified glass ionomer cement. Clinical and radiographic successes and failures were recorded at 6, 12, 18 and 24-month follow-up. Results All pulpotomised teeth were clinically and radiographically successful at all follow-up appointments. Six out of 15 teeth in the PC group and five out of 14 teeth in the MTA group exfoliated throughout the follow-up period. No statistically significant difference regarding dentine bridge formation was found between both groups throughout the follow-up period. As far as pulp canal obliteration is concerned, a statistically significant difference was detected at 6-month follow-up (p < 0.05), since the beginning of mineralised material deposition could be radiographically detected in 100% and 57.14% of the teeth treated with PC and MTA, respectively. Conclusions PC may serve as an effective and less expensive MTA substitute in primary molar pulpotomies. Further studies and longer follow-up assessments are needed.

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This study investigated the response of human alveolar bone-derived cells to a novel poly(vinylidene fluoride-trifluoroethylene)/barium titanate (P(VDF-TrFE)/BT) membrane. Osteoblastic cells were cultured in osteogenic conditions either on P(VDF-TrFE)/BT or polytetrafluoroethylene (PTFE) for up to 14 days. At 7 and 14 days, the mRNA expression of Runt-related transcription factor 2 (RUNX2), Type I collagen (COL I), Osteopontin (OPN), Alkaline phosphatase (ALP), Bone sialoprotein (BSP), and Osteocalcin (OC), key markers of the osteoblastic phenotype, and of Bcl2-associated X protein (Bax), B-cell CLL/lymphoma 2 (Bcl-2), and Survivin (SUR), associated with the control of the apoptotic cell death, was assayed by real-time PCR. In situ ALP activity was qualitatively evaluated by means of Fast red staining. Surface characterization was also qualitatively and quantitatively assayed in terms of topography, roughness, and wettability. Cells grown on P(VDF-TrFE)/BT exhibited a significantly higher mRNA expression for all markers compared to the ones on PTFE, except for Bcl-2, which was not detected for both groups. Additionally, Fast red staining was noticeably stronger in cultures on P(VDF-TrFE)/BT at 7 and 14 days. At micron-and submicron scale, SEM images and roughness analysis revealed that PTFE and P(VDF-TrFE)/BT exhibited a smooth topography and a similar roughness, respectively. PTFE membrane displayed higher contact angles compared with P(VDF-TrFE)/BT, as indicated by wettability assay. The novel P(VDF-TrFE)/BT membrane supports the acquisition of the osteoblastic phenotype in vitro, while up-regulating the expression of apoptotic markers. Further in vivo experiments should be carried out to confirm the capacity of P(VDF-TrFE)/BT membrane in promoting bone formation in guided bone regeneration.

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The mm of this work was to evaluate the biocompatibility of poly(vinylidene fluoride-trifluoroethylene)/barium titanate (P(VDF-TrFE)/BT) membrane to be used in guided tissue regeneration (GTR) Fibroblasts from human periodontal ligament (hPDLF) and keratinocytes (SCC9) were plated on P(VDF-TrFE)/BT and polytetrafluorethylene membranes at a cell density of 20.000 cells well(-1) and Cultured for up to 21 days Cell morphology, adhesion and proliferation were evaluated in hPDLF and keratinocytes, while total protein content and alkaline phosphatase (ALP) activity were assayed only for hPDLF Using a higher cell density. real-time polymerase chain reaction (PCR) was performed to assess the expression of typical genes of hPDLF, such as periostin, PDLs17, S100A4 and fibromodulin, and key phenotypic markers of keratinocytes, including involucrin, keratins 1. 10 and 14 Expression of the apoptotic genes bax, bcl-2 and Survivin was evaluated for both cultures hPDLF adhered and spread more oil P(VDF-TrFE)/BT, whereas keratinocytes showed a round shape on both membranes. hPDLF adhesion was greater oil P(VDF-TrFE)/BT at 2 and 4 h, while keratinocyte adhesion was similar for both membranes. Whereas proliferation was significantly higher for hPDLF on P(VDF-TrFE)/BT at days 1 and 7. no signs of keratinocyte proliferation could be noticed for both membranes Total protein content was greater on P(VDF-TrFE)/BT at 7, 14 and 21 days, and higher levels of ALP activity were observed oil P(VDF-TrFE)/BT at 21 days. Real-time PCR revealed higher expression of phenotypic markers of hPDLF and keratinocytes as well as greater expression of apoptotic genes in cultures grown on P(VDF-TrFE)/BT. These results indicate that, by favoring hPDLF adhesion. spreading. proliferation and typical mRNA expression, P(VDF-TrFE)/BT membrane should be considered an advantageous alternative for GTR (C) 2009 Acta Materialia Inc Published by Elsevier Ltd All rights reserved

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Eag1 (K(v)10.1) is the founding member of an evolutionarily conserved superfamily of voltage-gated K+ channels. In rats and humans Eag1 is preferentially expressed in adult brain but its regional distribution has only been studied at mRNA level and only in the rat at high resolution. The main aim of the present study is to describe the distribution of Eag1 protein in adult rat brain in comparison to selected regions of the human adult brain. The distribution of Eag1 protein was assessed using alkaline-phosphatase based immunohistochemistry. Eag1 immunoreactivity was widespread, although selective, throughout rat brain, especially noticeable in the perinuclear space of cells and proximal regions of the extensions, both in rat and human brain. To relate the results to the relative abundance of Eag1 transcripts in different regions of rat brain a reverse-transcription coupled to quantitative polymerase chain reaction (real time PCR) was performed. This real time PCR analysis showed high Eag1 expression in the olfactory bulb, cerebral cortex, hippocampus, hypothalamus, and cerebellum. The results indicate that Eag1 protein expression greatly overlaps with mRNA distribution in rats and humans. The physiological relevance of potassium channels in the different regions expressing Eag1 protein is discussed. (C) 2008 IBRO. Published by Elsevier Ltd. All rights reserved.

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it has been demonstrated that the effect of GH on bone tissue is reduced with aging. In this study we tested the hypothesis that the action of GH on osteoblastic cells is donor-age-dependent by investigating the effect of GH on the development of osteoblastic phenotype in cultures of cells from adolescents (13-16 years old), young adults (18-35 years old), and adults (36-49 years old). Osteoblastic cells derived from human alveolar bone were cultured with or without GH for periods of up to 21 days, and parameters of in vitro osteogenesis and gene expression of osteoblastic markers were evaluated. GH increased culture growth, collagen content and alkaline phosphatase (ALP) activity in cultures from adolescents and young adults, whereas non-significant effect was observed in cultures from adults. While GH significantly increased the bone-like formation in cultures from adolescents, a slightly effect was observed in cultures from young adults and no alteration was detected in cultures from adults. Results from real-time PCR demonstrated that GH upregulated ALP, osteocalcin, type I collagen, and Cbfa1 mRNA levels in cultures from adolescents. In addition, cultures from young adults showed higher ALP mRNA expression and the expression of all evaluated genes was not affected by GH in cultures from adults. These results indicate that the GH effect on both in vitro osteogenesis and gene expression of osteoblastic markers is donor-age-dependent, being more pronounced on cultures from adolescents.

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One cause of congenital lactic acidosis is a mutation in the E1 alpha -subunit of the pyruvate dehydrogenase multienzyme complex. Little is known about the consequences of these mutations at the enzymatic level. Here we study the A199T mutation by expressing the protein in Escherichia coil. The specific activity is 25% of normal and the K-m for pyruvate is elevated by 10-fold. Inhibitors of lactate dehydrogenase might be a useful therapy for patients with such mutations. (C) 2001 Academic Press.

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Human S100A12 (extracellular newly identified RAGE (receptor for advanced glycosylation end products)binding protein), a new member of the S100 family of EF-hand calcium-binding proteins, was chemically synthesised using highly optimised 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate/tert-butoxycarbonyl in situ neutralisation solid-phase chemistry. Circular dichroism studies indicated that CaCl2 decreased the helical content by 27% whereas helicity was marginally increased by ZnCl2. The propensity of S100A12 to dimerise was examined by electrospray ionisation time-of-flight mass spectrometry which clearly demonstrated the prevalence of the non-covalent homodimer (20 890 Da). Importantly, synthetic human S100A12 in the nanomolar range was chemotactic for neutrophils and macrophages in vitro. (C) 2001 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.

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The inhibition of recombinant CYP1A1 and CYP1A2 activity by quinidine and quinine was evluated using ethoxyresorufin O -deethylation, phenacetin O -deethylation and propranolol desisopropylation as probe catalytic pathways. 2. With substrate concentrations near the K m of catalysis, both quinidine and quinine potently inhibited CYP1A1 activity with [ I ] 0.5 ~ 1-3 μM, whereas in contrast, there was little inhibition of CYP1A2 activity. The Lineweaver-Burk plots with varying inhibitor concentrations suggested that inhibition by quinidine and quinine was competitive. 3. There was only trace metabolism of quinidine by recombinant CYP1A1, whereas rat liver microsomes as a control showed extensive consumption of quinidine and metabolite production. 4. This work suggests that quinidine is a non-classical inhibitor of CYP1A1 and that it is not as highly specific at inhibiting CYP2D6 as previously thought.