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The acute toxicity of cylindrospermopsin (CYN) has been established in rodents, based on diverse intraperitoneal an oral exposure studies and more recently in fish. But no data have been reported in fish after subchronic exposure to cyanobacterial cells containing this cyanotoxin, so far. In this work, tilapia (Oreochromis niloticus) were exposed by immersion to lyophilized Aphanizomenon ovalisporum cells added to the aquaria using two concentration levels of CYN (10 or 100 μg CYN L?1) and deoxy‐cylindrospermopsin (deoxy‐CYN) (0.46 or 4.6 μg deoxy‐CYN L?1), during two different exposure times: 7 or 14 d. This is the first study showing damage in the liver, kidney, hearth, intestines, and gills of tilapia after subchronic exposure to cyanobacterial cells at environmental relevant concentrations. The major histological changes observed were degenerative processes and steatosis in the liver, membranous glomerulopathy in the kidney, myofibrolysis and edema in the heart, necrotic enteritis in the gastrointestinal tract, and hyperemic processes in gill lamellae and microhemorrhages. Moreover, these histopathological findings confirm that the extent of damage is related to the CYN concentration and length of exposure. Results from the morphometric study indicated that the average of nuclear diameter of hepatocytes and cross‐sections of proximal and distal convoluted tubules are useful to evaluate the damage induced by CYN in the main targets of toxicity. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 261–277, 2015.  相似文献   
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The objective of this study was to assess the degree of concordance between two popular classification systems [the Centers for Disease Control and Prevention (CDC)‐2000 and the Institute of Medicine (IOM)‐2009] used to categorise the nutritional status of pregnant adolescents. This cross‐sectional study involved 327 pregnant adolescents (10–19 years) booking for antenatal care at a single public maternity in São Paulo, Brazil. Participants were classified into one of four categories, by both systems according to their pre‐pregnancy body mass index and age. The CDC‐2000 system classified significantly fewer pregnant adolescents as underweight (3.7% vs. 12.5%, P < 0.0001) and significantly more adolescents as normal‐weight (86.8% vs. 75.6%, P = 0.0003) than the IOM‐2009 system. The distribution of the adolescents in the two systems differed significantly. The global rate of discordance was 13.5%. The overall concordance between the two systems was marginally good (K = 0.63), being moderate for younger (<16 years) adolescents (K = 0.52). Approximately one in every seven pregnant adolescent would be classified in a non‐corresponding category if the IOM‐2009 classification was used instead of the CDC‐2000 classification. The IOM‐2009 nutritional classification, which does not take into account age and gender, tends to overestimate the proportion of underweight adolescents, especially in the younger‐age group. The use of this classification system can lead to recommendations of higher gestational weight gain in a substantial proportion of pregnant adolescents, which could predispose to post‐partum weight retention and future obesity.  相似文献   
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Objectives: To observe the distribution of patients who presented with low back pain (LBP) and to determine the between therapists’ interrater reliability of assessments in a private outpatient setting using treatment-based classification (TBC) subgroups.

Methods: An observational and methodological study was conducted. Four hundred and twenty-nine patients (231 male; 198 female) presenting LBP symptoms and referred to conservative treatment were assessed by 13 physical therapists who conducted a 60-min examination process utilizing TBC subgroups. Interrater reliability analyses from six raters were assessed using Fleiss’ kappa and previously recorded data (n = 30).

Results: In this study, 65.74% of patients were classified in only one subgroup, the most prevalent being stabilization (21.91%), followed by extension (15.38%), traction (11.89%), flexion (10.96%), manipulation (5.13%), and lateral shift (0.47%). Approximately 20.98% of patients were classified in two subgroups, where the most frequent overlaps were flexion + stabilization (7.46%), extension + stabilization (6.06%), flexion + traction (4.20%), extension + manipulation (1.86%), and 13.29% of patients were not classified in any TBC subgroup. Analysis of interrater reliability showed a kappa value of 0.62 and an overall agreement of 66% between raters.

Discussion: LBP is a heterogeneous clinical condition and several classification methods are proposed in the attempt to observe better outcomes for patients. Eighty-five percent of patients assessed were able to be classified when using the TBC assessment and reliability analysis showed a substantial agreement between raters.

Level of Evidence: 2c.  相似文献   

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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   
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Nearly all countries in the world today are burdened with malnutrition, manifesting as undernutrition, micronutrient deficiencies, and/or overweight and obesity. Despite some progress, efforts to alleviate malnutrition are hampered by a shortage in number, skills, and geographic coverage, of a workforce for nutrition. Here, we report the findings of the Castel Gandolfo workshop, a convening of experts from diverse fields in March 2014 to consider how to develop the capacity of a global cadre of nutrition professionals for the post-2015 development era. Workshop participants identified several requirements for developing a workforce for nutrition, including an ability to work as part of a multisectoral team; communication, advocacy, and leadership skills to engage decision makers; and a set of technical skills to address future challenges for nutrition. Other opportunities were highlighted that could immediately contribute to capacity development, including the creation of a consortium to link global North and South universities, online training modules for middle managers, and practical, hands-on experiences for frontline nutrition workers. Institutional and organizational support is needed to enable workshop recommendations on education and training to be effectively implemented and sustained. The findings from the Castel Gandolfo workshop can contribute to the delivery of successful nutrition-relevant actions in the face of mounting external pressures and informing and attaining the forthcoming Sustainable Development Goals.  相似文献   
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