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排序方式: 共有436条查询结果,搜索用时 31 毫秒
131.
Nayeli Monterrosas-Brisson Mayra Zagal-Guzmán Alejandro Zamilpa Enrique Jiménez-Ferrer Margarita Avilés-Flores Macrina Fuentes-Mata Maribel Herrera-Ruiz 《化学与生物多样性》2021,18(3):e2000790
Argemone mexicana L. is a widely used plant in Mexican traditional medicine to treat inflammatory and nervous medical conditions. It has been subjected to several pharmacological and chemical studies in which acute anti-inflammatory activity is indicated. This work aimed at finding an extract and fraction with anti-inflammatory activity by means of 2-O-tetradecanoylphorbol-13-acetate (TPA)-induced auricular edema. Afterward, the extract and the fraction were tested on neuroinflammation caused by lipopolysaccharides (LPS). Treatments obtained from A. mexicana included the methanolic extract (AmMeOH), a fraction extracted with ethyl acetate (AmAcOEt), and four sub-fractions (AmF-1 to AmF-4), which were evaluated in auricular edema with the TPA assay. Both treatments with the most significant inhibitory effect were employed to test these in the LPS neuroinflammation model. AmAcOEt and AmF-3 induced a higher inhibition of edema (%), and both diminished ear inflammation when viewed under a microscope. These treatments also raised an increase in spleen, but not in brain of mice with neuroinflammation. They were able to decrease the concentration of proinflammatory cytokines (TNF-α, IL-1β, and IL-6) in both organs. Furthermore, the accumulation of amyloid-β (Aβ) in hippocampus was not visible. AmF-3 contains the flavonoids isoquercetin, luteolin, and rutin, the former being the most concentrated. 相似文献
132.
Jordi Adamuz Diego Viasus Antonella Simonetti Emilio Jiménez-Martínez Lorena Molero Maribel González-Samartino Elena Castillo María-Eulalia Juvé-Udina María-Jesús Alcocer Carme Hernández María-Pilar Buera Asunción Roel Emilia Abad Adelaida Zabalegui Pilar Ricart Anna Gonzalez Pilar Isla Jordi Dorca Carolina Garcia-Vidal Jordi Carratalà 《PloS one》2015,10(10)
Background
Additional healthcare visits and rehospitalizations after discharge are frequent among patients with community-acquired pneumonia (CAP) and have a major impact on healthcare costs. We aimed to determine whether the implementation of an individualized educational program for hospitalized patients with CAP would decrease subsequent healthcare visits and readmissions within 30 days of hospital discharge.Methods
A multicenter, randomized trial was conducted from January 1, 2011 to October 31, 2014 at three hospitals in Spain. We randomly allocated immunocompetent adults patients hospitalized for CAP to receive either an individualized educational program or conventional information before discharge. The educational program included recommendations regarding fluid intake, adherence to drug therapy and preventive vaccines, knowledge and management of the disease, progressive adaptive physical activity, and counseling for alcohol and smoking cessation. The primary trial endpoint was a composite of the frequency of additional healthcare visits and rehospitalizations within 30 days of hospital discharge. Intention-to-treat analysis was performed.Results
We assigned 102 patients to receive the individualized educational program and 105 to receive conventional information. The frequency of the composite primary end point was 23.5% following the individualized program and 42.9% following the conventional information (difference, -19.4%; 95% confidence interval, -6.5% to -31.2%; P = 0.003).Conclusions
The implementation of an individualized educational program for hospitalized patients with CAP was effective in reducing subsequent healthcare visits and rehospitalizations within 30 days of discharge. Such a strategy may help optimize available healthcare resources and identify post-acute care needs in patients with CAP.Trial Registration
Controlled-Trials.com ISRCTN39531840 相似文献133.
Makowski MR Wiethoff AJ Blume U Cuello F Warley A Jansen CH Nagel E Razavi R Onthank DC Cesati RR Marber MS Schaeffter T Smith A Robinson SP Botnar RM 《Nature medicine》2011,17(3):383-388
Atherosclerosis and its consequences remain the main cause of mortality in industrialized and developing nations. Plaque burden and progression have been shown to be independent predictors for future cardiac events by intravascular ultrasound. Routine prospective imaging is hampered by the invasive nature of intravascular ultrasound. A noninvasive technique would therefore be more suitable for screening of atherosclerosis in large populations. Here we introduce an elastin-specific magnetic resonance contrast agent (ESMA) for noninvasive quantification of plaque burden in a mouse model of atherosclerosis. The strong signal provided by ESMA allows for imaging with high spatial resolution, resulting in accurate assessment of plaque burden. Additionally, plaque characterization by quantifying intraplaque elastin content using signal intensity measurements is possible. Changes in elastin content and the high abundance of elastin during plaque development, in combination with the imaging properties of ESMA, provide potential for noninvasive assessment of plaque burden by molecular magnetic resonance imaging (MRI). 相似文献
134.
Oxidative stress is known to play important roles in engineered nanomaterial‐induced cellular toxicity. However, the proteins and signaling pathways associated with the engineered nanomaterial‐mediated oxidative stress and toxicity are largely unknown. To identify these toxicity pathways and networks that are associated with exposure to engineered nanomaterials, an integrated proteomic study was conducted using human bronchial epithelial cells, BEAS‐2B and nanoscale titanium dioxide. Utilizing 2‐DE and MS, we identified 46 proteins that were altered at protein expression levels. The protein changes detected by 2‐DE/MS were verified by functional protein assays. These identified proteins include some key proteins involved in cellular stress response, metabolism, adhesion, cytoskeletal dynamics, cell growth, cell death, and cell signaling. The differentially expressed proteins were mapped using Ingenuity Pathway Analyses? canonical pathways and Ingenuity Pathway Analyses tox lists to create protein‐interacting networks and proteomic pathways. Twenty protein canonical pathways and tox lists were generated, and these pathways were compared to signaling pathways generated from genomic analyses of BEAS‐2B cells treated with titanium dioxide. There was a significant overlap in the specific pathways and lists generated from the proteomic and the genomic data. In addition, we also analyzed the phosphorylation profiles of protein kinases in titanium dioxide‐treated BEAS‐2B cells for a better understanding of upstream signaling pathways in response to the titanium dioxide treatment and the induced oxidative stress. In summary, the present study provides the first protein‐interacting network maps and novel insights into the biological responses and potential toxicity and detoxification pathways of titanium dioxide. 相似文献
135.
Joaquín Herrero Francisco Fernández-Pérez Tatiana Yebra Esther Novo-Uzal Federico Pomar Mª Ángeles Pedreño Juan Cuello Alfredo Guéra Alberto Esteban-Carrasco José Miguel Zapata 《Planta》2013,237(6):1599-1612
Lignins result from the oxidative polymerization of three hydroxycinnamyl (p-coumaryl, coniferyl, and sinapyl) alcohols in a reaction mediated by peroxidases. The most important of these is the cationic peroxidase from Zinnia elegans (ZePrx), an enzyme considered to be responsible for the last step of lignification in this plant. Bibliographical evidence indicates that the arabidopsis peroxidase 72 (AtPrx72), which is homolog to ZePrx, could have an important role in lignification. For this reason, we performed a bioinformatic, histochemical, photosynthetic, and phenotypical and lignin composition analysis of an arabidopsis knock-out mutant of AtPrx72 with the aim of characterizing the effects that occurred due to the absence of expression of this peroxidase from the aspects of plant physiology such as vascular development, lignification, and photosynthesis. In silico analyses indicated a high homology between AtPrx72 and ZePrx, cell wall localization and probably optimal levels of translation of AtPrx72. The histochemical study revealed a low content in syringyl units and a decrease in the amount of lignin in the atprx72 mutant plants compared to WT. The atprx72 mutant plants grew more slowly than WT plants, with both smaller rosette and principal stem, and with fewer branches and siliques than the WT plants. Lastly, chlorophyll a fluorescence revealed a significant decrease in ΦPSII and q L in atprx72 mutant plants that could be related to changes in carbon partitioning and/or utilization of redox equivalents in arabidopsis metabolism. The results suggest an important role of AtPrx72 in lignin biosynthesis. In addition, knock-out plants were able to respond and adapt to an insufficiency of lignification. 相似文献
136.
Victor Camera Pimentel Daniela Zanini Andréia Machado Cardoso Roberta Schmatz Margarete Dulce Bagatini Jessié Martins Gutierres Fabiano Carvalho Jéssica Lopes Gomes Maribel Rubin Vera Maria Morsch Maria Beatriz Moretto Mariana Colino-Oliveira Ana Maria Sebastião Maria Rosa Chitolina Schetinger 《Neurochemical research》2013,38(4):886-894
It is well known that the levels of adenosine in the brain increase dramatically during cerebral hypoxic-ischemic (HI) insults. Its levels are tightly regulated by physiological and pathophysiological changes that occur during the injury acute phase. The aim of the present study was to examine the effects of the neonatal HI event on cytosolic and ecto-enzymes of purinergic system––NTPDase, 5′-nucleotidase (5′-NT) and adenosine deaminase (ADA)––in cerebral cortex of rats immediately post insult. Furthermore, the Na+/K+-ATPase activity, adenosine kinase (ADK) expression and thiobarbituric acid reactive species (TBARS) levels were assessed. Immediately after the HI event the cytosolic NTPDase and 5′-NT activities were increased in the cerebral cortex. In synaptosomes there was an increase in the ecto-ADA activity while the Na+/K+ ATPase activity presented a decrease. The difference between ATP, ADP, AMP and adenosine degradation in synaptosomal and cytosolic fractions could indicate that NTPDase, 5′-NT and ADA were differently affected after insult. Interestingly, no alterations in the ADK expression were observed. Furthermore, the Na+/K+-ATPase activity was correlated negatively with the cytosolic NTPDase activity and TBARS content. The increased hydrolysis of nucleotides ATP, ADP and AMP in the cytosol could contribute to increased adenosine levels, which could be related to a possible innate neuroprotective mechanism aiming at potentiating the ambient levels of adenosine. Together, these results may help the understanding of the mechanism by which adenosine is produced following neonatal HI injury, therefore highlighting putative therapeutical targets to minimize ischemic injury and enhance recovery. 相似文献
137.
Carole D. Mitnick Molly F. Franke Michael L. Rich Felix A. Alcantara Viru Sasha C. Appleton Sidney S. Atwood Jaime N. Bayona Cesar A. Bonilla Katiuska Chalco Hamish S. F. Fraser Jennifer J. Furin Dalia Guerra Rocio M. Hurtado Keith Joseph Karim Llaro Lorena Mestanza Joia S. Mukherjee Maribel Mu?oz Eda Palacios Epifanio Sanchez Kwonjune J. Seung Sonya S. Shin Alexander Sloutsky Arielle W. Tolman Mercedes C. Becerra 《PloS one》2013,8(3)
Rationale
A better understanding of the composition of optimal treatment regimens for multidrug-resistant tuberculosis (MDR-TB) is essential for expanding universal access to effective treatment and for developing new therapies for MDR-TB. Analysis of observational data may inform the definition of an optimized regimen.Objectives
This study assessed the impact of an aggressive regimen–one containing at least five likely effective drugs, including a fluoroquinolone and injectable–on treatment outcomes in a large MDR-TB patient cohort.Methods
This was a retrospective cohort study of patients treated in a national outpatient program in Peru between 1999 and 2002. We examined the association between receiving an aggressive regimen and the rate of death.Measurements and Main Results
In total, 669 patients were treated with individualized regimens for laboratory-confirmed MDR-TB. Isolates were resistant to a mean of 5.4 (SD 1.7) drugs. Cure or completion was achieved in 66.1% (442) of patients; death occurred in 20.8% (139). Patients who received an aggressive regimen were less likely to die (crude hazard ratio [HR]: 0.62; 95% CI: 0.44,0.89), compared to those who did not receive such a regimen. This association held in analyses adjusted for comorbidities and indicators of severity (adjusted HR: 0.63; 95% CI: 0.43,0.93).Conclusions
The aggressive regimen is a robust predictor of MDR-TB treatment outcome. TB policy makers and program directors should consider this standard as they design and implement regimens for patients with drug-resistant disease. Furthermore, the aggressive regimen should be considered the standard background regimen when designing randomized trials of treatment for drug-resistant TB. 相似文献138.
Ema Carina Rosas-Burgos Mario Onofre Cortez-Rocha Maribel Plascencia-Jatomea Francisco Javier Cinco-Moroyoqui Ramón Enrique Robles-Zepeda Jaime López-Cervantes Dalia Isabel Sánchez-Machado Fernando Lares-Villa 《World journal of microbiology & biotechnology》2011,27(5):1025-1033
The aim of this study was to evaluate the effect of Baccharis glutinosa isolated extract on the growth of Aspergillus flavus and Aspergillus parasiticus, and their aflatoxin B1 production; and growth of Fusarium verticillioides, and their fumonisin B1 production. The three fungi were exposed to an antifungal fraction, designated as fraction F6-1, isolated from B. glutinosa by methanolic extraction followed by silica gel chromatography. The growth of the fungi was evaluated in kinetics of radial
extension growth, kinetics of spores germination, length and diameter of hyphae, spores diameter, as well as in aflatoxin
B1 and fumonisin B1 production. Fraction F6-1 caused radial growth inhibition of the three fungi mainly F. verticillioides. Spores germination of A. flavus and A. parasiticus was delayed in the early stage of the incubation time, although they completely germinated at 27 h. In contrast, spore germination
of F. verticillioides was inhibited 87.7% up to 96 h. The lengths and diameters of hyphae, and spore diameters of the three fungi, were significantly
smaller in comparison with those of the controls, and several morphological alterations were observed. Concerning aflatoxin
B1 and fumonisin B1, fraction F6-1 did not show any inhibition effect at the concentration used. Fraction F6-1 was able to significantly inhibit
the development of the three fungi, mainly F. verticillioides. The strong inhibitory effect of F6-1 on hyphae and spores suggests that it interacted with the fungi cell walls, which caused
severe deformities. Nevertheless, this fraction was unable in inhibiting mycotoxin production from the three fungi at the
concentration tested. 相似文献
139.
The amount of ionic current flowing through K(+) channels is determined by the interplay between two separate time-dependent processes: activation and inactivation gating. Activation is concerned with the stimulus-dependent opening of the main intracellular gate, whereas inactivation is a spontaneous conformational transition of the selectivity filter toward a nonconductive state occurring on a variety of timescales. A recent analysis of multiple x-ray structures of open and partially open KcsA channels revealed the mechanism by which movements of the inner activation gate, formed by the inner helices from the four subunits of the pore domain, bias the conformational changes at the selectivity filter toward a nonconductive inactivated state. This analysis highlighted the important role of Phe103, a residue located along the inner helix, near the hinge position associated with the opening of the intracellular gate. In the present study, we use free energy perturbation molecular dynamics simulations (FEP/MD) to quantitatively elucidate the thermodynamic basis for the coupling between the intracellular gate and the selectivity filter. The results of the FEP/MD calculations are in good agreement with experiments, and further analysis of the repulsive, van der Waals dispersive, and electrostatic free energy contributions reveals that the energetic basis underlying the absence of inactivation in the F103A mutation in KcsA is the absence of the unfavorable steric interaction occurring with the large Ile100 side chain in a neighboring subunit when the intracellular gate is open and the selectivity filter is in a conductive conformation. Macroscopic current analysis shows that the I100A mutant indeed relieves inactivation in KcsA, but to a lesser extent than the F103A mutant. 相似文献
140.
Balbontín J Hermosell IG Marzal A Reviriego M De Lope F Møller AP 《The Journal of animal ecology》2007,76(5):915-925
1. We investigated age-related changes in two reproductive traits (laying date and annual fecundity) in barn swallows Hirundo rustica L. using a mixed model approach to di-stinguish among between- and within-individual changes in breeding performance with age. 2. We tested predictions of age-related improvements of competence (i.e. constraint hypothesis) and age-related progressive disappearance of poor-quality breeders (i.e. selection hypothesis) to explain age-related increase in breeding performance in early life. 3. Reproductive success increased in early life, reaching a plateau at middle age (e.g. at 3 years of age) and decreasing at older age (> 4 years). Age-related changes in breeding success were due mainly to an effect of female age. 4. Age of both female and male affected timing of reproduction. Final linear mixed effect models (LME) for laying date included main and quadratic terms for female and male age, suggesting a deterioration in reproductive performance at older age for both males and females. 5. We found evidence supporting the constraints hypothesis that increases in competence within individuals, with ageing being the most probable cause of the observed increase in breeding performance with age in early life. Two mechanisms were implicated: (1) advance in male arrival date with age provided middle-aged males with better access to mates. Yearling males arrived later to the breeding grounds and therefore had limited access to high-quality mates. (2) Breeding pairs maintaining bonds for 2 consecutive years (experienced pairs) had higher fecundity than newly formed inexperienced breeding pairs. 6. There was no support for the selection hypothesis because breeding performance was not correlated with life span. 7. We found a within-individual deterioration in breeding and migratory performance (arrival date) in the oldest age-classes consistent with senescence in these reproductive and migratory traits. 相似文献