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171.
Martini Claudia Sosa Fernando Nicolas Malvicini Ricardo Pacienza Natalia Yannarelli Gustavo del C. Vila María 《Journal of physiology and biochemistry》2021,77(4):601-611
Journal of Physiology and Biochemistry - Alendronate, a bisphosphonate used to prevent osteoporosis, stimulates osteogenesis but impairs adipogenesis. Different clinical trials suggest that the... 相似文献
172.
Kathryn M. Maselli Gabriel Levin Kristin M. Gee Elisabeth J. Leeflang Ana Claudia O. Carreira Mari Cleide Sogayar Tracy C. Grikscheit 《Biochemistry and Biophysics Reports》2021
BackgroundR-spondins, including R-spondin 1 (RSPO1), are a family of Wnt ligands that help to activate the canonical Wnt/β-catenin pathway, which is critical for intestinal epithelial cell proliferation and maintenance of intestinal stem cells. This proliferation underpins the epithelial expansion, or intestinal adaptation (IA), that occurs following massive bowel resection and short bowel syndrome (SBS). The purpose of this study was to identify if recombinant human RSPO1 (rhRSPO1) could be serially administered to SBS zebrafish to enhance cellular proliferation and IA.MethodsAdult male zebrafish were assigned to four groups: sham + PBS, SBS + PBS, sham + rhRSPO1, and SBS + rhRSPO1. Sham fish had a laparotomy alone. SBS fish had a laparotomy with distal intestinal ligation and creation of a proximal stoma. Fish were weighed at initial surgery and then weekly. rhRSPO1 was administered post-operatively following either a one- or two-week dosing schedule with either 3 or 5 intraperitoneal injections, respectively. Fish were harvested at 7 or 14 days with intestinal segments collected for analysis.ResultsRepeated intraperitoneal injection of rhRSPO1 was feasible and well tolerated. At 7 days, intestinal epithelial proliferation was increased by rhRSPO1. At 14 days, SBS + rhRSPO1 fish lost significantly less weight than SBS + PBS fish. Measurements of intestinal surface area were not increased by rhRSPO1 administration but immunofluorescent staining for β-catenin and gene expression for cyclin D1 was increased.ConclusionsIntraperitoneal injection of rhRSPO1 decreased weight loss in SBS zebrafish with increased β-catenin + cells and cyclin D1 expression at 14 days, indicating improved weight maintenance might result from increased activation of the canonical Wnt pathway. 相似文献
173.
Maria Claudia Cardoso Pereira Valdinar de Araújo Rocha Júnior Martim Bottaro Marcelino Monteiro de Andrade Fabiano Peruzzo Schwartz André Martorelli Rodrigo Celes Jake Carvalho Carmo 《Journal of electromyography and kinesiology》2013,23(2):448-454
The relationship between surface electromyography (SEMG) amplitude and the ventilatory threshold has been extensively studied. However, previous studies of muscle fiber conduction velocity (MFCV) are scarce and present insufficient evidence concerning the relationship between MFCV and metabolic responses during cycling. Based on that fact, the purpose of this study is twofold: (1) to investigate the existence of a MFCV threshold (MFCVT) during cycling and (2) to verify if this possible breakpoint is correlated with the ventilatory threshold (VT) and the SEMG threshold (SEMGT). Eight trained male cyclists (age 36.0 ± 9.7 years) performed an incremental cycling test with initial workload of 150 W gradually incremented by 20 W min?1 until the exhaustion. Gas analyses were conducted using a breath-by-breath open-circuit spirometry and SEMG were registered from vastus lateralis in each pedaling cycle with a linear array of electrodes. A bi-segmental linear regression computer algorithm was used to estimate VT, MFCVT and SEMGT respectively in the carbon dioxide production (VCO2), MFCV and electromyography root mean square (EMG RMS) curves. The one way ANOVA for repeated measures did not reveal any significant difference among VT (77.1 ± 7.5% of VO2max), MFCVT (80.3 ± 10.4% of VO2max) and SEMGT (81.9 ± 11.7% of VO2max). The Bland and Altman procedure confirmed a good concordance between SEMGT and VT (Bias = 5.5 of %VO2max) as well as MFCVT and VT (Bias = 5.2 of %VO2max). The present findings suggest that muscle fiber conduction velocity threshold is a valid and reliable non-invasive tool to obtain information about ventilatory threshold in trained cyclists. 相似文献
174.
Acid mine drainage (AMD) barrens result from destruction of vegetation within AMD flow paths. When exposed to air, soluble iron in AMD undergoes oxidation and hydrolysis to form ferric iron (oxyhydr)oxides which accumulate on soil surfaces. A restoration experiment was conducted at a 50‐year‐old AMD barrens created by discharge from an abandoned underground coal mine. The objective was to determine whether vegetation could be established by altering rather than removing surface layers of acidic precipitates at a site representative of other mining‐degraded areas. Three zones in the barrens were identified based on moisture content, pH (2.7–3.3), and thickness of precipitates (0–35 cm). Our hypothesis was that application of the same reclamation method to all zones would fail to sustain >70% vegetative cover in each zone after four growing seasons. The method consisted of applying 11 t/ha lime and 27 or 54 t/ha compost before rototilling (top 15 cm) and mulching with oat straw containing viable seeds for a nurse crop. Lime‐only plots were included for comparison, and all amended plots were sown with a mine reclamation seed mix. Oats, sown species, and indigenous species dominated cover in the first, second, and fourth growing seasons, respectively. In the fourth year following reclamation, compost‐amended plots had >70% cover and improved soil properties in all three zones, providing evidence to reject our hypothesis. Vegetative restoration of AMD barrens did not require removal of highly acidic precipitates, since they could be transformed at low‐cost into a medium that supports indigenous plants. 相似文献
175.
Jazmin M. Pérez-Rojas Cristino Cruz Patricia García-López Dolores J. Sánchez-González Claudia M. Martínez-Martínez Gisela Ceballos 《Free radical research》2013,47(11):1122-1132
Cisplatin (CDDP) is a chemotherapeutic agent that produces nephrotoxicity associated with oxidative/nitrosative stress. α-Mangostin (α-M) is a xanthone extracted from mangosteen with antioxidant and anti-inflammatory properties. The purpose of this study was to evaluate the renoprotective effect of α-M on the CDDP-induced nephrotoxicity. α-M was administered (12.5 mg/kg/day, i.g.) for 10 days (7 days before and 3 days after CDDP injection). On day 7, rats were treated with a single injection of CDDP (7.5 mg/Kg, i.p.); 3 days after the rats were killed. α-M attenuated renal dysfunction, structural damage, oxidative/nitrosative stress, decrease in catalase expression and increase in mRNA levels of tumour necrosis factor alpha and transforming growth factor beta. In conclusion the renoprotective effect of α-M on CDDP-induced nephrotoxicity was associated with the attenuation in oxidative/nitrosative stress and inflammatory and fibrotic markers and preservation of catalase activity. 相似文献
176.
Pierre Sicard Stéphanie Delemasure Claudia Korandji Anabelle Segueira-Le grand Benjamin Lauzier Jean-Claude Guilland 《Free radical research》2013,47(3):226-236
Among their pleiotropic effects, statins exert antioxidant and anti-inflammatory properties. The aim of this study was to evaluate in normotensive (WKY) and in spontaneously hypertensive rats (SHR) the effect of rosuvastatin (ROSU) treatment on (1) plasma inflammation markers and endogenous NO synthase inhibitor (ADMA) levels, (2) reactive oxygen species (ROS) generated by circulating leukocytes and (3) vascular oxidative stress and tissue inflammation markers. Plasma cytokines were higher in SHR than in WKY, except for IL-4, which was lower in SHR than in WKY. SHR monocytes exhibited higher production of ROS than did WKY monocytes. In the experimental conditions, ROSU did not modify plasma cholesterol levels in SHR but attenuated the increase in systolic blood pressure. In SHR only, ROSU lessened pro-inflammatory cytokines and ADMA levels, increased IL-4 and reduced ROS production in circulating monocytes. These results demonstrate the beneficial effects of ROSU in SHR, independently of any lowering of cholesterol levels. 相似文献
177.
Régis A. Zanette Laerte Ferreiro Sydney H. Alves Francielli P.K. Jesus Claudia Lautert Andréia Spanamberg Janio M. Santurio 《Revista iberoamericana de micología》2013,30(4):264-266
BackgroundPythium insidiosum is an oomycete classified in the kingdom Stramenopila. P. insidiosum hyphae are not able to initiate infection without the secretion of hydrolytic enzymes, which are considered an important factor in microbial virulence.AimsTo evaluate the extracellular enzymatic activity of 14 Brazilian P. insidiosum isolates and a standard strain (ATCC 58637) by the API-ZYM System screening method.MethodsZoospores were grown in RPMI 1640 broth, and 65 μL of the liquid phase were inoculated in each cupule of the API-ZYM strips.ResultsDifferences in the enzymatic activities were observed among the isolates, although phosphohydrolases and ester hydrolases were conspicuous among all isolates. β-glucosidase was also present in most of the isolates. Enzymatic activities of α-glucosidase and chymotrypsin were not observed, differing from a previous study involving Australian isolates and intracellular enzymes.ConclusionsThe discrepancy in the enzymatic profile observed among Brazilian P. insidiosum isolates reflects the phenotypic variations found in susceptibility tests. 相似文献
178.
Nicola Bizzaro Elena Bartoloni Gabriella Morozzi Stefania Manganelli Valeria Riccieri Paola Sabatini Matteo Filippini Marilina Tampoia Antonella Afeltra Giandomenico Sebastiani Claudia Alpini Vittorio Bini Onelia Bistoni Alessia Alunno Roberto Gerli 《Arthritis research & therapy》2013,15(1):R16
Introduction
The diagnostic, predictive and prognostic role of anti-cyclic citrullinated peptide (CCP) antibodies in rheumatoid arthritis (RA) patients is widely accepted. Moreover, detection of these antibodies in subjects presenting with undifferentiated arthritis (UA) is associated with a significant risk to develop the disease. On the other hand, clinical and prognostic significance of evaluating anti-CCP levels in subjects with inflammatory arthritis at disease onset has not been fully clarified. The goal of this prospective study is to analyze the value and prognostic significance of anti-CCP titer quantification in UA subjects.Methods
Serial anti-CCP assays were measured in 192 consecutive patients presenting with UA lasting less than 12 weeks. Clinical and serological data and arthritis outcome were evaluated every 6 months until two years of follow-up.Results
Anti-CCP positivity, at both low and high titer, and arthritis of hand joints significantly predicted RA at two years, risk increasing in subjects with high anti-CCP titers at baseline. Moreover, time to RA diagnosis was shorter in patients with high anti-CCP2 titers at enrollment with respect to those with low antibody concentration.Conclusions
Presence of anti-CCP antibodies, at both low and high concentration, is significantly associated with RA development in subjects with recent onset UA. However, time interval from the onset of the first symptoms to the fulfilment of the classification criteria appears to be directly related to the initial anti-CCP level. 相似文献179.
Raffaele Saladino Paola Carlucci Claudia Crestini Pietro Tagliatesta Donato Monti Tristano Boschi 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):1123-1124
Abstract The oxidation of purine derivatives using porphyrins as catalysts and dimethyldioxirane (DMDO) as oxygen atom donor is reported. The regioselectivity of the oxidation was found to be dependent on the presence of a free OH moiety on the N(9)-side chain of the substrate and on the structure of the catalyst. 相似文献
180.