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131.
Luiz Fernando Mendes Leonardo Zambotti-Villela Pio Colepicolo Eliane Marinho-Soriano Cassius Vinicius Stevani Nair Sumie Yokoya 《Journal of applied phycology》2013,25(6):1939-1947
Macroalgae of the genus Gracilaria have considerable economic importance as raw material for agar production and belong to an important group of organisms that are tolerant of high concentrations of metal. The median inhibitory concentration (IC50) values obtained by measuring the ratio of fresh mass variation (i.e., daily growth rates) of the red macroalga Gracilaria domingensis during a 48-h aquatic toxicity assay are reported here. The alga was exposed to 14 different metal cations as well as the molybdate anion in synthetic seawater. The actual concentrations of these ionic species (at IC50 values) and the proportion of free ions (aqueous complexes) were determined by inductively coupled plasma atomic emission spectroscopy and the Environmental Protection Agency-recommended software, MINTEQA2, respectively. Based on the free IC50 values (IC50 F), the ions were ranked in terms of toxicity: Cd2+???Cu2+???Pb2+???Zn2+???Ni2+?>?Co2+?>?La3+???Mn2+?>?Ca2+?~?Li+???MoO4 2????Sr2+?>?Mg2+???K+?>?Na+. As a member of the first trophic level in the marine food chain, G. domingensis is an appropriate target organism both for the development of toxicological assays and as a bioindicator of marine degradation. 相似文献
132.
Maria Inês Nogueira Claudia Perpétuo Pfeiffer Jackson Cioni Bittencourt Luis Eduardo Ribeiro do Vale 《Biological Rhythm Research》2013,44(3):245-260
Nucleus raphe pallidus (RPa) lies ventrally in the caudal brainstem, where it is coextensive rostrally with the nucleus raphe magnus (RMg) and caudally with the nucleus raphe obscurus (ROb). Retrograde neuronal tracing studies of our laboratory, carried out in rats and presented elsewhere, with fluorogold, true-blue or fast-blue, iontophoretically injected or by crystalline deposit, along the RPa extent, displayed many labeled pericaria at the preoptic area (POA), as well as lateral (LH) and dorsomedial (DMH) hypothalamus; paraventricular nucleus (PVN) and dorsal (DR) and median (MnR) raphe nuclei among others structures. In addition, RPa, which projects to the intermediolateral column, has been demonstrated to bear relation to many of the somatic-visceral functions also reported for POA. Iontophoretic injections of PHA-L, an anterograde tracer, in the POA subnuclei, presented terminal and varicose labeled fibers in RPa, as well as in the RMg, ROb, paraventricular thalamic (PVA), PVN and supraoptic nucleus (SO), LH, subparaventricular zone (sPVZ) and locus coeruleus (LC). Interestingly, POA, PVA, PVN, LH and SO have been described as retino- and suprachiasmatic-recipients. Taken together, these neuronal connections between brainstem raphe nuclei and POA, the similarity of functions to which they are related, as well as connections with other retino-suprachiasmatic-recipient structures, suggest that these caudal brainstem raphe nuclei could be part of the output system for the expression of some biological rhythms. 相似文献
133.
Carlos Alberto Pires Pereira Alexandre R. Marra Luis Fernando Aranha Camargo Ant?nio Carlos Campos Pignatari Teresa Sukiennik Paulo Renato Petersen Behar Eduardo Alexandrino Servolo Medeiros Julival Ribeiro Evelyne Gir?o Luci Correa Carla Guerra Irna Carneiro Carlos Brites Marise Reis Marta Antunes de Souza Regina Tranchesi Cristina U. Barata Michael B. Edmond Brazilian SCOPE Study Group 《PloS one》2013,8(7)
Background
Nosocomial bloodstream infections (nBSIs) are an important cause of morbidity and mortality and are the most frequent type of nosocomial infection in pediatric patients.Methods
We identified the predominant pathogens and antimicrobial susceptibilities of nosocomial bloodstream isolates in pediatric patients (≤16 years of age) in the Brazilian Prospective Surveillance for nBSIs at 16 hospitals from 12 June 2007 to 31 March 2010 (Br SCOPE project).Results
In our study a total of 2,563 cases of nBSI were reported by hospitals participating in the Br SCOPE project. Among these, 342 clinically significant episodes of BSI were identified in pediatric patients (≤16 years of age). Ninety-six percent of BSIs were monomicrobial. Gram-negative organisms caused 49.0% of these BSIs, Gram-positive organisms caused 42.6%, and fungi caused 8.4%. The most common pathogens were Coagulase-negative staphylococci (CoNS) (21.3%), Klebsiella spp. (15.7%), Staphylococcus aureus (10.6%), and Acinetobacter spp. (9.2%). The crude mortality was 21.6% (74 of 342). Forty-five percent of nBSIs occurred in a pediatric or neonatal intensive-care unit (ICU). The most frequent underlying conditions were malignancy, in 95 patients (27.8%). Among the potential factors predisposing patients to BSI, central venous catheters were the most frequent (66.4%). Methicillin resistance was detected in 37 S. aureus isolates (27.1%). Of the Klebsiella spp. isolates, 43.2% were resistant to ceftriaxone. Of the Acinetobacter spp. and Pseudomonas aeruginosa isolates, 42.9% and 21.4%, respectively, were resistant to imipenem.Conclusions
In our multicenter study, we found a high mortality and a large proportion of gram-negative bacilli with elevated levels of resistance in pediatric patients. 相似文献134.
Rogerio Faustino Ribeiro Jr Felipe F. Potratz Brunella M. M. Pavan Ludimila Forechi Filipe Lugon Moulin Lima Jonaina Fiorim Aurelia Araujo Fernandes Dalton Valentim Vassallo Ivanita Stefanon 《PloS one》2013,8(1)
Carvedilol has beneficial effects on cardiac function in patients with heart failure but its effect on ovariectomy-induced myocardial contractile dysfunction remains unclear. Estrogen deficiency induces myocardial contractile dysfunction and increases cardiovascular disease risk in postmenopausal women. Our aim was to investigate whether carvedilol, a beta receptor blocker, would prevent ovariectomy-induced myocardial contractile dysfunction. Female rats (8 weeks old) that underwent bilateral ovariectomy were randomly assigned to receive daily treatment with carvedilol (OVX+CAR, 20 mg/kg), placebo (OVX) and SHAM for 58 days. Left ventricle papillary muscle was mounted for isometric tension recordings. The inotropic response to Ca2+ (0.62 to 3.75 mM) and isoproterenol (Iso 10−8 to 10−2 M) were assessed. Expression of calcium handling proteins was measured by western blot analysis. Carvedilol treatment in the OVX animals: prevented weight gain and slight hypertrophy, restored the reduced positive inotropic responses to Ca2+ and isoproterenol, prevented the reduction in SERCA2a expression, abolished the increase in superoxide anion production, normalized the increase in p22phox expression, and decreased serum angiotensin converting enzyme (ACE) activity. This study demonstrated that myocardial contractile dysfunction and SERCA2a down regulation were prevented by carvedilol treatment. Superoxide anion production and NADPH oxidase seem to be involved in this response. 相似文献
135.
Eliane Volchan Isabel A. David Gisella Tavares Billy M. Nascimento Jose M. Oliveira Sonia Gleiser Andre Szklo Cristina Perez Tania Cavalcante Mirtes G. Pereira Leticia Oliveira 《PloS one》2013,8(8)
Objective
The use of pictorial warning labels on cigarette packages is one of the provisions included in the first ever global health treaty by the World Health Organization against the tobacco epidemic. There is substantial evidence demonstrating the effectiveness of graphic health warning labels on intention to quit, thoughts about health risks and engaging in cessation behaviors. However, studies that address the implicit emotional drives evoked by such warnings are still underexplored. Here, we provide experimental data for the use of pictorial health warnings as a reliable strategy for tobacco control.Methods
Experiment 1 pre-tested nineteen prototypes of pictorial warnings to screen for their emotional impact. Participants (n = 338) were young adults balanced in gender, smoking status and education. Experiment 2 (n = 63) tested pictorial warnings (ten) that were stamped on packs. We employed an innovative set-up to investigate the impact of the warnings on the ordinary attitude of packs’ manipulation, and quantified judgments of warnings’ emotional strength and efficacy against smoking.Findings
Experiment 1 revealed that women judged the warning prototypes as more aversive than men, and smokers judged them more aversive than non-smokers. Participants with lower education judged the prototypes more aversive than participants with higher education. Experiment 2 showed that stamped warnings antagonized the appeal of the brands by imposing a cost to manipulate the cigarette packs, especially for smokers. Additionally, participants’ judgments revealed that the more aversive a warning, the more it is perceived as effective against smoking.Conclusions
Health warning labels are one of the key components of the integrated approach to control the global tobacco epidemic. The evidence presented in this study adds to the understanding of how implicit responses to pictorial warnings may contribute to behavioral change. 相似文献136.
Parathyroidectomy Improves Survival In Patients with Severe Hyperparathyroidism: A Comparative Study
Patricia Taschner Goldenstein Rosilene Motta Elias Lilian Pires de Freitas do Carmo Fernanda Oliveira Coelho Luciene Pereira Magalh?es Gisele Lins Antunes Melani Ribeiro Custódio Fábio Luiz de Menezes Montenegro Silvia Maria Titan Vanda Jorgetti Rosa Maria Affonso Moysés 《PloS one》2013,8(8)
Background and objectives
Secondary hyperparathyroidism (SHPT) in CKD is associated with an increased risk for mortality, but definitive data showing that parathormone control decreases mortality is still lacking. This study aimed to compare the mortality of patients with severe SHPT submitted to parathyroidectomy(PTX) with those who did not have access to surgery.Methods
This is a retrospective study in a cohort of 251 CKD patients with severe SHPT who were referred to a CKD-MBD Center for PTX from 2005 until 2012.Results
Most of our patients had indication of PTX, but only 49% of them had access to this surgical procedure. After a mean follow-up of 23 months, 72 patients had died. Non-survivors were older; more often had diabetes, lower serum 25 vitamin D and mostly had not been submitted to surgery. The relative risk of death was lower in the PTX patients (0.428; 95% CI, 0.28 to 0.67; p<0.0001). After adjustments, mortality risk was dependent on age (1.04; 95% CI, 1.01 to 1.07; p = 0.002), 25 vitamin D (0.43; 95% CI, 0.24 to 0.81; p = 0.006) and no access to PTX (4.13; 95% CI, 2.16 to 7.88; p<0.0001). Results remained the same in a second model using the PTX date as the study start date for the PTX group.Conclusions
Our data confirms the benefit of PTX on mortality in patients with severe SHPT. The high mortality encountered in our population is significant and urges the need to better treat these patients. 相似文献137.
Egle Machado de Almeida Siqueira Fernanda Ribeiro Rosa Adriana Medeiros Fustinoni Lívia Pimentel de Sant'Ana Sandra Fernandes Arruda 《PloS one》2013,8(8)
The bioactive compounds content and the antioxidant activity (AA) of twelve fruits native to the Cerrado were compared with the Red Delicious apple by means of the antiradical efficiency (using the 2,2-diphenyl-1-picrylhydrazil assay/DPPH), ferric reducing antioxidant power (FRAP) and the β-carotene/linoleic system. The antiradical efficiency (AE) and the kinetic parameters (Efficient concentration/EC50 and time needed to reach the steady state to EC50 concentration/TEC50) of the DPPH curve were also evaluated for comparison with the Trolox equivalent (TE) values. A strong, significant and positive correlation was observed between the TE and AE values, whereas a weak and negative correlation was observed between TE and EC50, suggesting that the values of AE and TE are more useful for the determination of antiradical activity in fruits than the widely used EC50. The total phenolic content found in the fruits corresponded positively to their antioxidant activity. The high content of bioactive compounds (flavanols, anthocyanins or vitamin C) relative to the apple values found in araticum, cagaita, cajuzinho, jurubeba, lobeira, magaba and tucum corresponded to the high antioxidant activity of these fruits. Flavanols and anthocyanins may be the main bioactive components in these Cerrado fruits. The daily consumption of at least seven of the twelve Cerrado fruits studied, particularly, araticum, cagaita, lobeira and tucum, may confer protection against oxidative stress, and thus, they may prevent chronic diseases and premature aging. The findings of this study should stimulate demand, consumption and cultivation of Cerrado fruits and result in sustainable development of the region where this biome dominates. 相似文献
138.
139.
Marcelo Magioli Katia Maria Paschoaletto Micchi de Barros Ferraz Eleonore Zulnara Freire Setz Alexandre Reis Percequillo Michelle Viviane de Sá Santos Rondon Vanessa Villanova Kuhnen Mariana Cristina da Silva Canhoto Karen Evelyn Almeida dos Santos Claudia Zukeran Kanda Gabriela de Lima Fregonezi Helena Alves do Prado Mitra Katherina Ferreira Milton Cezar Ribeiro Priscilla Marqui Schmidt Villela Luiz Lehmann Coutinho Márcia Gonçalves Rodrigues 《European Journal of Wildlife Research》2016,62(4):431-446
140.
Ismail Eş Maycon Carvalho Ribeiro Samuel Rodrigues dos Santos Júnior Amin Mousavi Khaneghah Armando Garcia Rodriguez André Corrêa Amaral 《Bioprocess and biosystems engineering》2016,39(10):1487-1500
The whole-cell immobilization on chitosan matrix was evaluated. Bacillus sp., as producer of CGTase, was grown in solid-state and batch cultivation using three types of starches (cassava, potato and cornstarch). Biomass growth and substrate consumption were assessed by flow cytometry and modified phenol–sulfuric acid assays, respectively. Qualitative analysis of CGTase production was determined by colorless area formation on solid culture containing phenolphthalein. Scanning electron microscopy (SEM) analysis demonstrated that bacterial cells were immobilized on chitosan matrix efficiently. Free cells reached very high numbers during batch culture while immobilized cells maintained initial inoculum concentration. The maximum enzyme activity achieved by free cells was 58.15 U ml?1 (36 h), 47.50 U ml?1 (36 h) and 68.36 U ml?1 (36 h) on cassava, potato and cornstarch, respectively. CGTase activities for immobilized cells were 82.15 U ml?1 (18 h) on cassava, 79.17 U ml?1 (12 h) on potato and 55.37 U ml?1 (in 6 h and max 77.75 U ml?1 in 36 h) on cornstarch. Application of immobilization technique increased CGTase activity significantly. The immobilized cells produced CGTase with higher activity in a shorter fermentation time comparing to free cells. 相似文献