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101.
Average spectral power changes at the hippocampal electroencephalogram in schizophrenia model induced by ketamine 下载免费PDF全文
Luis Rafael L. Sampaio Lucas T.N. Borges Joyse M.F. Silva Francisca Roselin O. de Andrade Talita M. Barbosa Tatiana Q. Oliveira Danielle Macedo Ricardo F. Lima Leonardo P. Dantas Manoel Cláudio A. Patrocinio Silvânia M.M. Vasconcelos 《Fundamental & clinical pharmacology》2018,32(1):60-68
The use of ketamine (Ket) as a pharmacological model of schizophrenia is an important tool for understanding the main mechanisms of glutamatergic regulated neural oscillations. Thus, the aim of the current study was to evaluate Ket‐induced changes in the average spectral power using the hippocampal quantitative electroencephalography (QEEG). To this end, male Wistar rats were submitted to a stereotactic surgery for the implantation of an electrode in the right hippocampus. After three days, the animals were divided into four groups that were treated for 10 consecutive days with Ket (10, 50, or 100 mg/kg). Brainwaves were captured on the 1st or 10th day, respectively, to acute or repeated treatments. The administration of Ket (10, 50, or 100 mg/kg), compared with controls, induced changes in the hippocampal average spectral power of delta, theta, alpha, gamma low or high waves, after acute or repeated treatments. Therefore, based on the alterations in the average spectral power of hippocampal waves induced by Ket, our findings might provide a basis for the use of hippocampal QEEG in animal models of schizophrenia. 相似文献
102.
Gregory J. Feldman Ana R. Sousa David A. Lipson Lee Tombs Neil Barnes John H. Riley Sadhana Patel Ian Naya Chris Compton Bernardino Alcázar Navarrete 《Advances in therapy》2017,34(11):2518-2533
Introduction
We report the results of the first direct comparison of the once-daily fixed-dose long-acting muscarinic antagonist/long-acting β2-agonist (LAMA/LABA) combinations umeclidinium/vilanterol (UMEC/VI) and tiotropium/olodaterol (TIO/OLO) in patients with COPD.Methods
This was a randomized, two-period crossover open-label study in symptomatic patients with COPD [age 40 years or older, postbronchodilator forced expiratory volume in 1 s (FEV1) of 70% or less and 50% or more of predicted normal values, and modified Medical Research Council Dyspnoea Scale score of 2 or greater] not receiving inhaled corticosteroid therapy. Patients were randomized to receive UMEC/VI (62.5/25 µg once daily) via a multidose dry powder inhaler (ELLIPTA) followed by TIO/OLO (5/5 µg once daily) via a soft mist inhaler (Respimat), each for 8 weeks with an interim 3-week washout or vice versa. The primary end point was the change from baseline in trough FEV1 at week 8 with a noninferiority margin of ? 50 mL in the per-protocol (PP) population. The incidence of adverse events was also assessed.Results
In total, 236 patients (mean age 64.4 years, 60% male) were included in the intent-to-treat population and 227 were included in the PP population. UMEC/VI treatment was noninferior in the PP population and superior in the intent-to-treat population to TIO/OLO treatment with regard to trough FEV1 at week 8 [FEV1 change from baseline 180 mL vs 128 mL; difference 52 mL (95% confidence interval 28–77 mL); p < 0.001]. Patients receiving UMEC/VI had twofold increased odds of experiencing a clinically meaningful increase (100 mL or more) from baseline in trough FEV1 at week 8 compared with patients receiving TIO/OLO (odds ratio 2.05; 95% confidence interval 1.34–3.14). Adverse events occurred in 25% of patients in the UMEC/VI group and in 31% of patients in the TIO/OLO group.Conclusion
In this first direct comparison of two once-daily fixed-dose LAMA/LABA combinations, superiority was observed for the primary end point of trough FEV1 at week 8 with UMEC/VI compared with TIO/OLO in patients with symptomatic COPD. Both treatments had similar safety profiles. These findings confirm the results of previous indirect LAMA/LABA comparisons, and show that an efficacy gradient exists within the LAMA/LABA class.Trial Registration
ClinicalTrials.gov identifier NCT02799784.Funding
GlaxoSmithKline.103.
Single‐use flexible bronchoscopes compared with reusable bronchoscopes: Positive organizational impact but a costly solution 下载免费PDF全文
104.
Jung C Meinzer U Montcuquet N Thachil E Château D Thiébaut R Roy M Alnabhani Z Berrebi D Dussaillant M Pedruzzi E Thenet S Cerf-Bensussan N Hugot JP Barreau F 《The Journal of clinical investigation》2012,122(6):2239-2251
Intestinal barrier function requires intricate cooperation between intestinal epithelial cells and immune cells. Enteropathogens are able to invade the intestinal lymphoid tissue known as Peyer's patches (PPs) and disrupt the integrity of the intestinal barrier. However, the underlying molecular mechanisms of this process are poorly understood. In mice infected with Yersinia pseudotuberculosis, we found that PP barrier dysfunction is dependent on the Yersinia virulence plasmid and the expression of TLR-2 by hematopoietic cells, but not by intestinal epithelial cells. Upon TLR-2 stimulation, Y. pseudotuberculosis-infected monocytes activated caspase-1 and produced IL-1β. In turn, IL-1β increased NF-κB and myosin light chain kinase activation in intestinal epithelial cells, thus disrupting the intestinal barrier by opening the tight junctions. Therefore, Y. pseudotuberculosis subverts intestinal barrier function by altering the interplay between immune and epithelial cells during infection. 相似文献
105.
106.
Santos AO Ueda-Nakamura T Dias Filho BP Veiga Junior VF Pinto AC Nakamura CV 《Journal of ethnopharmacology》2008,120(2):204-208
Ethnopharmacological relevance
Copaiba oil has been used in folk medicine since the 19th century. The use of copaiba oils to treat leishmaniasis is cited in several ethnopharmacological studies. Nevertheless, the potential antileishmania of copaiba oils had not been studied.Aim of the study
Eight different kinds of Brazilian copaiba oils were screened for antileishmanial activity.Materials and methods
The antiproliferative effect of copaiba oil on promastigote and amastigote axenic were determined. To determine the survival index peritoneal macrophage were infected with promastigotes of Leishmania amazonensis and treated with copaiba oil. The cytotoxic effect of copaiba oil was assessed on macrophage strain J774G8 by assay of sulforhodamine B.Results
Copaiba oils showed variable levels of activity against promastigote forms with IC50 values in the range between 5 and 22 μg/mL. The most active oil was that from Copaifera reticulata (collected in Pará State, Brazil) with IC50 values of 5, 15, and 20 μg/mL for promastigote, axenic amastigote and intracellular amastigote forms, respectively. Amphotericin B showed IC50 of 0.058 and 0.231 μg/mL against promastigote and amastigote forms, respectively. Cytotoxicity assay showed that this copaiba oil obtained from Copaifera reticulata showed low cytotoxicity against J774G8 macrophages.Conclusion
Copaiba oils showed significant activity against the parasite Leishmania amazonensis. 相似文献107.
Koroishi AM Foss SR Cortez DA Ueda-Nakamura T Nakamura CV Dias Filho BP 《Journal of ethnopharmacology》2008,117(2):270-277
The present study was designated to evaluate the in vitro antidermatophyte activity of extracts from leaves of Piper regnellii as well as of the bioactivity-directed isolation of neolignans. The antifungal assay was performed by microdilution techniques. The hydroalcoholic extract of Piper regnellii leaves presented a strong activity against the dermatophyte fungi Trichophyton mentagrophytes, Trichophyton rubrum, Microsporum canis and Microsporum gypseum with MICs of 15.62, 15.62, 15.62 and 62.5 microg/ml, respectively. On light microscopy and scanning electron microscopy of nail fragments not exposed to hydroalcoholic extract of Piper regnelli leaves, well-formed and extensive mycelial growth was seen. On nail fragments exposed to hydroalcoholic extract at concentrations more than 1.2mg/ml and then inoculated with spore suspension, growth was not seen. The hydroalcoholic extract was fractionated on silica gel in to nine fractions. The active chloroform fraction was lyophilized and chromatographed by column chromatography on silica gel. Structures were established by comparison with literature data and identified as eupomatenoid-3 and eupomatenoid-5. The pure compounds showed strong activity on Trichophyton rubrum with MIC of 50 and 6.2 microg/ml, respectively. Comparing the activity of the active chloroform fraction obtained from hydroalcoholic crude extract with that of isolated compound eupomatenoid-5, it is clear that this showed the same results against Trichophyton rubrum. The results showed that the plant could be explored for possible antifungal agents and provides preliminary scientific validation for the traditional medicinal use of this plant. 相似文献
108.
Luciana Rodrigues da Cunha Diego Alves Vieira Yala Gramigna Giampietro Adriana Dias Gomes César Lúcio Lopes de Faria Jr Fabrício Freire de Melo Rosângela Teixeira Andrea Teixeira de Carvalho Luciana Maria Oliveira Olindo Assis Martins Filho Gifone Aguiar Rocha Dulciene Maria de Magalhães Queiroz Fernando Silva Neves Luciana Diniz Silva 《Clinics and research in hepatology and gastroenterology》2019,43(4):417-426
109.
Behaviour was assessed in 32 C57BL/6JCrl and 32 C3H/HeN male mice 1 h following vasectomy; saline or meloxicam was administered 30 min prior to surgery at 5, 10, or 20 mg kg(-1). Faeces were collected 24 h prior to, and 3, 6, 9, 12, 24 h following, vasectomy for measurement of faecal corticosterone. Peak corticosterone levels were significantly higher in mice that underwent vasectomy and received saline (p<0.001) or meloxicam at 5 or 10 mg kg(-1) (p=0.021, and p<0.001, respectively) compared with normal un-operated controls. Mice that underwent vasectomy and received 20 mg kg(-1) meloxicam had peak corticosterone levels that were not different from normal un-operated mice (p=0.254). Discriminant analysis was used to identify behaviours responsible for group separation; these were summed to create two behaviour scores. Score 2 (the frequency of flinching, writhing, rear leg lift and press 2) was thought to be pain related; mice that underwent vasectomy and received saline exhibited significantly more of these behaviours than the normal controls (p=0.032), and the mice that received meloxicam (at any dose). Strain differences were observed in both the stress response to vasectomy and the behavioural changes; the C3H/HeN mice had higher pain scores (behaviour Score 2) and peak corticosterone responses than the C57BL/6JCrl mice. We have demonstrated that significant changes occur in the behaviour of mice following vasectomy, and these changes are reduced by use of meloxicam. Vasectomy elicits a rise in corticosterone levels that was only reduced by the highest dose of meloxicam. 相似文献
110.
de Moraes Pantaleão S Alcântara AV Hora Alves Jdo P Pavanin LA Graf U de Rezende AA Bueno Valadares BL Fragiorge EJ de Souza NC Guterres Zda R Spanó MA 《Environmental and molecular mutagenesis》2007,48(2):96-105
The Drosophila melanogaster somatic mutation and recombination test (SMART) was used to assess the genotoxicity of surface (S) and bottom (B) water and sediment samples collected from Sites 1 and 2 on the Japaratuba River (Sergipe, Brazil), an area impacted by a petrochemical industrial complex that indirectly discharges treated effluent (produced water) into the river. The genotoxicity tests were performed in standard (ST) cross and high bioactivation (HB) cross flies and were conducted on samples taken in March (dry season) and in July (rainy season) of 2003. Mutant spot frequencies found in treatments with unprocessed water and sediment samples from the test sites were compared with the frequencies observed for similar samples taken from a clean reference site (the Jacarecica River in Sergipe, Brazil) and those of negative (ultrapure water) controls. While samples from the Japaratuba River generally produced greater responses than those from the Jacarecica River, positive responses were detected for both the test and reference site samples. All the water samples collected in March 2003 were genotoxic. In July 2003, the positive responses were restricted to water samples collected from Sites 1 B and 2 S in the ST cross. The genotoxicity of the water samples was due to mitotic recombination, and the samples produced similar genotoxic responses in ST and HB flies. The spot frequencies found in the July water samples were considerably lower than those for the March water samples, suggesting a seasonal effect. The only sediment samples that were genotoxic were from Site 1 (March and July) and from the Jacarecica River (March). The genotoxins in these samples produced both somatic mutation (limited to the Site 1 sample in HB flies) and recombination. The results of this study indicate that samples from both the Japaratuba and Jacarecica Rivers were genotoxic, with the most consistently positive responses detected with Site 1 samples, the site closest to the putative pollution source. 相似文献