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81.
Eve Wemelle Lionel Carneiro Anne Abot Jean Lesage Patrice D. Cani Claude Knauf 《Nutrients》2022,14(10)
(1) Background: Type 2 diabetes (T2D) is associated with a duodenal hypermotility in postprandial conditions that favors hyperglycemia and insulin resistance via the gut-brain axis. Enterosynes, molecules produced within the gut with effects on the enteric nervous system, have been recently discovered and pointed to as potential key modulators of the glycemia. Indeed, targeting the enteric nervous system that controls gut motility is now considered as an innovative therapeutic way in T2D to limit intestinal glucose absorption and restore the gut-brain axis to improve insulin sensitivity. So far, little is known about the role of glucose on duodenal contraction in fasted and fed states in normal and diabetic conditions. The aim of the present study was thus to investigate these effects in adult mice. (2) Methods: Gene-expression level of glucose transporters (SGLT-1 and GLUT2) were quantified in the duodenum and jejunum of normal and diabetic mice fed with an HFD. The effect of glucose at different concentrations on duodenal and jejunal motility was studied ex vivo using an isotonic sensor in fasted and fed conditions in both normal chow and HFD mice. (3) Results: Both SGLT1 and GLUT2 expressions were increased in the duodenum (47 and 300%, respectively) and jejunum (75% for GLUT2) of T2D mice. We observed that glucose stimulates intestinal motility in fasted (200%) and fed (400%) control mice via GLUT2 by decreasing enteric nitric oxide release (by 600%), a neurotransmitter that inhibits gut contractions. This effect was not observed in diabetic mice, suggesting that glucose sensing and mechanosensing are altered during T2D. (4) Conclusions: Glucose acts as an enterosyne to control intestinal motility and glucose absorption through the enteric nervous system. Our data demonstrate that GLUT2 and a reduction of NO production could both be involved in this stimulatory contracting effect. 相似文献
82.
Inês E. Oliveira Ricardo M. Silva Joana Rodrigues Maria R. Correia Teresa Monteiro Joaquim L. Faria Rui F. Silva Cludia G. Silva 《RSC advances》2022,12(26):16419
Titanium oxide (TiO2) has been widely investigated as a photocatalytic material, and the fact that its performance depends on its crystalline structure motivates further research on the relationship between preparation methods and material properties. In this work, TiO2 thin films were grown on non-functionalized wave-like patterned vertically aligned carbon nanotubes (w-VA-CNTs) via the atomic layer deposition (ALD) technique. Grazing incidence X-ray diffraction (GIXRD) analysis revealed that the structure of the TiO2/VA-CNT nanocomposites varied from amorphous to a crystalline phase with increasing deposition temperature, suggesting a “critical deposition temperature” for the anatase crystalline phase formation. On the other hand, scanning transmission electron microscopy (STEM) studies revealed that the non-functionalized carbon nanotubes were conformally and homogeneously coated with TiO2, forming a nanocomposite while preserving the morphology of the nanotubes. X-ray photoelectron spectroscopy (XPS) provided information about the surface chemistry and stoichiometry of TiO2. The photodegradation experiments under ultraviolet (UV) light on a model pollutant (Rhodamine B, RhB) revealed that the nanocomposite comprised of anatase crystalline TiO2 grown at 200 °C (11.2 nm thickness) presented the highest degradation efficiency viz 55% with an illumination time of 240 min. Furthermore, its recyclability was also demonstrated for multiple cycles, showing good recovery and potential for practical applications.Amorphous or anatase crystalline TiO2/VA-CNT nanocomposites were grown controlling the synthesis temperature. Photocatalytic degradation of RhB of 55% was achieved after 240 min. The immobilized material remains active after 4 cycles of use. 相似文献
83.
Tatiane Teixeira Oliveira Keina Maciele Campos Ana Tereza Cerqueira-Lima Tamires Cana Brasil Carneiro Eudes da Silva Velozo Ingrid Christie Alexandrino Ribeiro Melo Eugênia Abrantes Figueiredo Eduardo de Jesus Oliveira Darizy Flávia Silva Amorim de Vasconcelos Lain Carlos Pontes-de-Carvalho Neuza Maria Alcantara-Neves Camila Alexandrina Figueiredo 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2015,23(1)
Background
Asthma is an inflammatory condition characterized by airway hyperresponsiveness and chronic inflammation. The resolution of inflammation is an essential process to treat this condition. In this study we investigated the effect of Allium cepa L. extract (AcE) and quercetin (Qt) on cytokine and on smooth muscle contraction in vitro and its therapeutic potential in a murine model of asthma.Methods
AcE was obtained by maceration of Allium cepa L. and it was standardized in terms of quercetin concentration using high performance liquid chromatography (HPLC). In vitro, using AcE 10, 100 or 1000 μg/ml or Qt 3.5, 7.5, 15 μg/ml, we measured the concentration of cytokines in spleen cell culture supernatants, and the ability to relax tracheal smooth muscle from A/J mice. In vivo, Blomia tropicalis (BT)-sensitized A/J mice were treated with AcE 100, 1000 mg/kg or 30 mg/kg Qt. We measured cell influx in bronchoalveolar lavage (BAL), eosinophil peroxidase (EPO) in lungs, serum levels of Bt-specific IgE, cytokines levels in BAL, and lung histology.Results
We observed a reduction in the production of inflammatory cytokines, a relaxation of tracheal rings, and a reduction in total number of cells in BAL and EPO in lungs by treatment with AcE or Qt.Conclusion
AcE and Qt have potential as antiasthmatic drugs, as they possess both immunomodulatory and bronchodilatory properties. 相似文献84.
Comparison of cardiac function in male and female diabetic rats 总被引:1,自引:0,他引:1
To examine the influence of sex differences in the STZ model of diabetes, we studied left ventricular function in hearts from 6 week old male and female rats. Significantly lower values for +dP/dt occurred in male diabetic rats compared with their own controls or female diabetics at most left atrial filling pressures. Decreases in this value for female diabetic rats compared to their own controls occurred only at high left atrial pressures. It appears that diabetes mellitus produces greater myocardial dysfunction in male diabetic rats. 相似文献
85.
Camilla Rodrigues de Almeida Ribeiro Katrini Guidolini Martinelli Vinícius da Motta de Mello Natlia Spitz Oscar Rafael Carmo Araújo Lia Laura Lewis-Ximenez Natalia Motta Araujo Vanessa Salete de Paula 《Viruses》2022,14(7)
Several hepatitis B virus (HBV)-related factors, including the viral load, genotype, and genomic mutations, have been linked to the development of liver diseases. Therefore, in this study we aimed to investigate the influence of HBV genetic variability during acute and chronic infection phases. A real-time nested PCR was used to detect HBV DNA in all samples (acute, n = 22; chronic, n = 49). All samples were sequenced for phylogenetic and mutation analyses. Genotype A, sub-genotype A1, was the most common genotype in the study population. A total of 190 mutations were found in the pre-S/S gene area and the acute profile revealed a greater number of nucleotide mutations (p < 0.05). However, both profiles contained nucleotide mutations linked to immune escape and an increased risk of hepatocellular carcinomas (acute, A7T; chronic, A7Q). Furthermore, 17 amino acid substitutions were identified in the viral polymerase region, including the drug resistance mutations lamivudine and entecavir (rtL180M), with statistically significant differences between the mutant and wild type strains. Owing to the natural occurrence of these mutations, it is important to screen for resistance mutations before beginning therapy. 相似文献
86.
Elma Izze da Silva Magalhes Bianca Rodrigues de Oliveira Lívia Carolina Sobrinho Rudakoff Vitria Abreu de Carvalho Poliana Cristina de Almeida Fonseca Viola Soraia Pinheiro Machado Arruda Carolina Abreu de Carvalho Carla Cristine Nascimento da Silva Coelho Maylla Luanna Barbosa Martins Bragana Heloisa Bettiol Marco Antnio Barbieri Viviane Cunha Cardoso Alcione Miranda dos Santos Renata Bertazzi Levy Antnio Augusto Moura da Silva 《Nutrients》2022,14(15)
Longitudinal studies evaluating the relationship between UPF consumption and the incidence of Metabolic Syndrome (MetS) and its components are still scarce. This study aimed to evaluate the effect of UPF consumption on the incidence of MetS and its components in adults. A prospective study was conducted with 896 participants from the 1978/79 Ribeirão Preto cohort, São Paulo, Brazil. UPF consumption was evaluated in %kcal and %g at ages 23–25 years. Incidence of MetS and its components were estimated at ages 37–39 years, according to the Joint Interim Statement criteria. Poisson regression was used to assess associations, and interactions with sex were investigated. UPF consumption had no association with MetS (%kcal Adjusted PR: 1.00; 95% CI: 0.99–1.01; %g Adjusted PR: 1.00; 95% CI: 0.99–1.01). However, women with higher UPF consumption, in %kcal and %g, had a higher risk of abdominal obesity (%kcal: p = 0.030; %g: p = 0.003); and women with higher UPF consumption, in %g, had a higher risk of low HDL-cholesterol (p = 0.041). For the other components of MetS, no significant associations were observed in either sex. These findings suggest evidence of no association between UPF consumption and MetS; however, consumption of UPF was associated with increased WC and low HDL-c, but only in women. 相似文献
87.
Anterior clear spaces were observed prospectively at slit-lamp examination in 26 of 69 consecutive eyes (38%) with keratoconus. Two corneal buttons with this finding were examined by light and electron microscopy and revealed breaks in Bowman's layer. Anterior clear spaces should be considered in the spectrum of clinical findings in keratoconus. 相似文献
88.
José?Rodrigues?PereiraEmail author Sandro?J?Martins Sueli?M?Nikaedo Flora?K?Ikari 《BMC cancer》2004,4(1):69
Background
Although modest improvements in the survival of patients with non-small cell lung cancer (NSCLC) can be achieved with cisplatin-based chemotherapy (CT), its value is disputed in the geriatric setting. In this study, we evaluate the feasibility of vinorelbine/cisplatin CT for elderly NSCLC patients. 相似文献89.
Hydatid disease, manifesting as single or multiple hydatid cysts and caused by Echinococcus granulosus, is common in many parts of the world, especially the tropical countries. Although rare, this disease can also present during pregnancy, especially in endemic areas. Although much has been written about hepatic hydatidosis, there are only a few articles (mainly case reports) on hydatid disease in association with pregnancy. A literature search was done through Medline/PubMed and Medscape independently by the authors from 1950 to 2007 for key words "echinococcosis" and "pregnancy" and "management." All retrieved articles were reviewed. Manual cross-referencing was also done with inclusion of all relevant articles. In this review, we have attempted to summarize the presentation and available management approaches to hydatid disease, and have suggested evidence-based guidelines for its management during pregnancy. 相似文献
90.
Jorge MP Madjarof C Gois Ruiz AL Fernandes AT Ferreira Rodrigues RA de Oliveira Sousa IM Foglio MA de Carvalho JE 《Journal of ethnopharmacology》2008,118(3):361-366
ETHNOPHARMACOLOGICAL RELEVANCE: Arrabidaea chica Verlot. (Bignoniaceae), popularly known as Crajiru, has been traditionally used as wound healing agent. AIM OF THE STUDY: Investigate in vitro and in vivo healing properties of Arrabidaea chica leaves extract (AC). MATERIALS AND METHODS: AC was evaluated in vitro in fibroblast growth stimulation (0.25-250 microg/mL) and collagen production stimulation (250 microg/mL) assays. Allantoin (0.25-250 microg/mL) and vitamin C (25 microg/mL) were used as controls respectively. DPPH and Folin-Ciocalteau assays were used for antioxidant evaluation, using trolox (0.25-250 microg/mL) as reference antioxidant. To study wound healing properties in rats, AC (100mg/mL, 200 microL/wound/day) was topically administered during 10 days and wound area was evaluated every day. Allantoin (100mg/mL, 200 microL/wound/day) was used as standard drug. After treatment, wound sites were removed for histopathological analysis and total collagen determination. RESULTS: AC stimulated fibroblast growth in a concentration dependent way (EC50=30 microg/mL), increased in vitro collagen production and demonstrated moderate antioxidant capacity. In vivo, AC reduced wound size in 96%, whereas saline group showed only 36% wound healing. CONCLUSION: AC efficiency seems to involve fibroblast growing stimulus and collagen synthesis both in vitro and in vivo, beyond moderate scavenging activity, corroborating Crajiru folk use. 相似文献