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81.
Bravo R Caltabiano LM Fernandez C Smith KD Gallegos M Whitehead RD Weerasekera G Restrepo P Bishop AM Perez JJ Needham LL Barr DB 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,820(2):229-236
We have developed a method to measure 12 urinary phenolic metabolites of pesticides or related chemicals. The target chemicals for our method are 2-isopropoxyphenol; 2,4-dichlorophenol; 2,5-dichlorophenol; carbofuranphenol; 2,4,5-trichlorophenol; 2,4,6-trichlorophenol; 3,5,6-trichloro-2-pyridinol; para-nitrophenol, ortho-phenylphenol, pentachlorophenol, 1-naphthol and 2-naphthol. The sample preparation involves enzyme hydrolysis, isolation of the target chemicals using solid phase extraction cartridges, a phase-transfer catalyzed derivatization, cleanup using sorbent-immobilized liquid/liquid extraction cartridges, and concentration of the sample. Derivatized samples are analyzed by capillary gas chromatography-tandem mass spectroscopy using isotope dilution calibration for quantification. The limits of detection are in the mid ng/L range and the average coefficient of variation was below 15% for most of the analytes. Using our method, we measured concentrations of the target chemicals in urine samples from the general population. 相似文献
82.
Navarro M Goitia H Silva P Velásquez M Ojeda LE Fraile G 《Journal of inorganic biochemistry》2005,99(8):1630-1636
The metal-chloroquine (CQ) complexes, Cu(CQ)2Cl (1), Cu(CQ)(PPh3)(NO3) (2), [Cu(OAc)2(CQ)]2 (3) ZnCl2(CQ)(H2O)2 (4), [Zn(OAc)2(CQ)(H2O)]2 (5), were synthesized and characterized by NMR, FAB-mass, elemental analysis, and UV-Vis, EPR and IR spectroscopies. The effects of these compounds on the generation of reactive oxygen species (ROS) from human neutrophils (PMNs) were tested in the concentration range 1-100 microM and compared to that of chloroquine. The data show that the copper-chloroquine complexes 1-3 inhibit neutrophil release of ROS in PMNs activated either by a phorbol ester or by phagocytosable particles. Both effects were dose-dependent, with an IC50 of approximately 10 microM. With the same stimulants, there was only modest inhibition of ROS generation by any of the zinc-chloroquine complexes 4-5 at 10-100 microM. All complexes did not show significant in vitro toxicity as assayed by the trypan blue exclusion method. Our results reinforce previous observations that many metal derivatives of anti-inflammatory drugs affect neutrophil functions with higher potency than their parent ligands. 相似文献
83.
Tsevi I Vicente R Grande M López-Iglesias C Figueras A Capellà G Condom E Felipe A 《Journal of cellular physiology》2005,202(2):400-410
KCNQ1/KCNE1 channels are responsible for the Jervell-Lange-Nielsen cardiac syndrome, which is also characterized by congenital deafness. KCNQ1/KCNE1 is crucial for K+ transport in the inner ear. We show that KCNQ1 and KCNE1 are associated in testis and that their expression is closely regulated during development. Both genes were expressed in undifferentiated germ cells in 21-day-old rats and mostly confined to basal immature germ cells in adulthood. Leydig and Sertoli cells were negative. KCNQ1 and KCNE1 were also studied in various germ-cell pathologies. First, in spontaneous unilateral rat testis atrophy, hematoxylin-eosin analysis revealed massive germ-cell aplasia with only Sertoli cells and groups of interstitial Leydig cells. In these samples, KCNQ1 and KCNE1 were not expressed. In human seminoma samples characterized by a proliferation of undifferentiated germ cells, KCNQ1/KCNE1 protein levels were higher than in healthy samples. Our results demonstrate that the expression of KCNQ1 and KCNE1 is associated with early stages of spermatogenesis and with the presence of undifferentiated healthy or neoplastic germ cells. The presence of a K+ rich-fluid in the seminiferous tubule suggests that KCNQ1/KCNE1 is involved in K+ transport, probably during germ-cell development. 相似文献
84.
85.
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
86.
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87.
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
88.
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
89.
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90.
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