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261.
Barth OM Barreto DF Paes MV Takiya CM Pinhão AT Schatzmayr HG 《Memórias do Instituto Oswaldo Cruz》2006,101(8):905-915
One of the main difficulties in studying dengue virus infection in humans and in developing a vaccine is the absence of a suitable animal model which develops the full spectrum of dengue fever, dengue haemorrhagic fever, and dengue shock syndrome. It is our proposal to present morphological aspects of an animal model which shows many similarities with the dengue infection in humans. BALB/c mice were intraperitoneally infected with non-neuroadapted dengue virus serotype 2 (DENV-2). Histopathological and morphometrical analyses of liver tissue revealed focal alterations along the infection, reaching wide-ranging portal and centrolobular veins congestion and sinusoidal cell death. Additional ultrastructural observations demonstrated multifocal endothelial injury, platelet recruitment, and alterated hepatocytes. Dengue virus antigen was detected in hepatocytes and in the capillar endothelium of the central lobular vein area. Liver function tests showed high levels of aspartate transaminase and alanine transaminase enzyme activity. Lung tissue showed interstitial pneumonia and mononuclear cells, interseptal oedema, hyperplasia, and hypertrophy of the bronchiolar epithelial cells. DENV-2 led to a transient inflammatory process, but caused focal alterations of the blood-exchange barrier. Viremia was observed from 2nd to 11th day p.i. by isolation of DENV-2 in C6/36 mosquito cell line inoculated with the supernatant of macerated liver, lung, kidney, and cerebellum tissues of the infected mice. 相似文献
262.
Helton C. Delicio Ana C. Luchiari Rodrigo E. Barreto Ana L. Marcondes 《Journal of Ethology》2006,24(2):195-200
Time–place learning based on food association was investigated in the fish Nile tilapia. During a 30-day period, food was placed at one side of the aquarium (containing three compartments) in the morning and at the opposite side in the afternoon. Learning was inferred by the number of correct side choices of all fish in each day of test (15th, 30th). During the test day, fish were not fed. The Nile tilapia did not learn to switch sides at the correct day period in order to get food, suggesting thus that this species does not have time–place learning ability. 相似文献
263.
Philip J Cooper Martha E Chico Maritza G Vaca Alejandro Rodriguez Neuza M Alcântara-Neves Bernd Genser Lain Pontes de Carvalho Renato T Stein Alvaro A Cruz Laura C Rodrigues Mauricio L Barreto 《BMC pulmonary medicine》2006,6(1):1-9
Background
This study examined the attitudes and actions of 3415 physician-recruited adults aged ≥ 16 years with asthma in eleven countries who were prescribed regular maintenance therapy with inhaled corticosteroids or inhaled corticosteroids plus long-acting β2-agonists.Methods
Structured interviews were conducted to assess medication use, asthma control, and patients' ability to recognise and self-manage worsening asthma.Results
Despite being prescribed regular maintenance therapy, 74% of patients used short-acting β2-agonists daily and 51% were classified by the Asthma Control Questionnaire as having uncontrolled asthma. Even patients with well-controlled asthma reported an average of 6 worsenings/year. The mean period from the onset to the peak symptoms of a worsening was 5.1 days. Although most patients recognised the early signs of worsenings, the most common response was to increase short-acting β2-agonist use; inhaled corticosteroids were increased to a lesser extent at the peak of a worsening.Conclusion
Previous studies of this nature have also reported considerable patient morbidity, but in those studies approximately three-quarters of patients were not receiving regular maintenance therapy and not all had a physician-confirmed diagnosis of asthma. This study shows that patients with asthma receiving regular maintenance therapy still have high levels of inadequately controlled asthma. The study also shows that patients recognise deteriorating asthma control and adjust their medication during episodes of worsening. However, they often adjust treatment in an inappropriate manner, which represents a window of missed opportunity. 相似文献264.
Miagostovich MP dos Santos FB Fumian TM Guimarães FR da Costa EV Tavares FN Coelho JO Nogueira RM 《Memórias do Instituto Oswaldo Cruz》2006,101(3):307-313
We have determined the complete nucleotide and the deduced amino acid sequences of Brazilian dengue virus type 3 (DENV-3) from a dengue case with fatal outcome, which occurred during an epidemic in the state of Rio de Janeiro, Brazil, in 2002. This constitutes the first complete genetic characterization of a Brazilian DENV-3 strain since its introduction into the country in 2001. DENV-3 was responsible for the most severe dengue epidemic in the state, based on the highest number of reported cases and on the severity of clinical manifestations and deaths reported. 相似文献
265.
The paper briefly describes Canada's distinctive experience in the control of polio and offers some lessons for governments and health policy leaders in other jurisdictions, particularly as they consider immunization policies for the post-polio-eradication era. 相似文献
266.
Maja Bulatovi? ?alasan Oscar FC van den Bosch Marjonne CW Creemers Martijn Custers Antonius HM Heurkens Jan Maarten van Woerkom Nico M Wulffraat 《Arthritis research & therapy》2013,15(6):R217
Introduction
The aim of this study was to determine the prevalence of gastrointestinal and behavioural symptoms occurring before (anticipatory/associative) and after methotrexate (MTX) administration, termed MTX intolerance, in rheumatoid (RA) and psoriatic arthritis (PsA).Methods
Methotrexate Intolerance Severity Score (MISS), previously validated in juvenile idiopathic arthritis patients, was used to determine MTX intolerance prevalence in 291 RA/PsA patients. The MISS consisted of four domains: abdominal pain, nausea, vomiting and behavioural symptoms, occurring upon, prior to (anticipatory) and when thinking of MTX (associative). MTX intolerance was defined as ≥6 on the MISS with ≥1 point on anticipatory and/or associative and/or behavioural items.Results
A total of 123 patients (42.3%) experienced at least one gastrointestinal adverse effect. The prevalence of MTX intolerance was 11%. MTX intolerance prevalence was higher in patients on parenteral (20.6%) than on oral MTX (6.2%) (p < 0.001).Conclusion
Besides well-known gastrointestinal symptoms after MTX, RA and PsA patients experienced these symptoms also before MTX intake. RA and PsA patients on MTX should be closely monitored with the MISS for early detection of MTX intolerance, in order to intervene timely and avoid discontinuation of an effective treatment. 相似文献267.
Gabriela Pereira Teixeira Alessandra de Castro Ferreira Barreto Maria Carliana Mota 《Chronobiology international》2013,30(10):1418-1428
ABSTRACTStudies have suggested that eating at later times may be a risk factor for being overweight. The aim of this study was to investigate the association of caloric midpoint on the anthropometric profile and calorie and macronutrient intake during the day. The study included 718 Brazilian undergraduate students (20.5 ± 2.9 years old; 67% women). Dietary intake was assessed by 24-h recall and the diurnal variation of calorie consumption was evaluated by caloric midpoint average time at which 50% of daily energy were consumed. Participants were classified into two groups according to caloric midpoint median; early eaters (caloric midpoint ≤ 3:00 pm) or late eaters (caloric midpoint > 3:00 pm). Body weight and waist circumference were measured and body mass index (BMI) was determined. Generalized linear models adjusted for confounding variables were used to determine the association between variables. The late eaters presented higher BMI when compared to early eaters (23.0 kg/m2 ± 0.3 vs. 22.1 kg/m2 ± 0.2, respectively; p = .02). Late eaters reported a higher total daily consumption of energy (p < .001) and proportion consumed after 9:00 pm (p < .001), as well as total daily carbohydrate (p < .001), protein (p < .001), fat (p < .001), saturated fat (p < .001), and cholesterol (p = .04) intake when compared with early eaters. We conclude that concentrating food intake later in the day is associated with higher total energy and macronutrient intake as well as a higher average BMI. 相似文献
268.
269.
270.
Zanatta L Zamoner A Gonçalves R Zanatta AP Bouraïma-Lelong H Carreau S Silva FR 《Biochemistry》2011,50(47):10284-10292
1α,25-Dihydroxyvitamin D(3) (1,25D(3)) is the active metabolite of vitamin D(3) and the major calcium regulatory hormone in tissues. The aim of this work was to investigate the mechanism of action of 1,25D(3) on (45)Ca(2+) uptake in Sertoli cells from 30-day-old rats. Results showed that 10(-9) and 10(-12) M 1,25D(3) increased the rate of (45)Ca(2+) uptake 5 and 15 min after hormone exposure and that 1α,25(OH)(2) lumisterol(3) (JN) produced a similar effect suggesting that 1,25D(3) action occurs via a putative membrane receptor. The involvement of voltage-dependent calcium channels (VDCC) in 1,25D(3) action was evidenced by using nifedipine, while the use of Bapta-AM demonstrated that intracellular calcium was not implicated. Moreover, the incubation with ouabain and digoxin increased the rate of (45)Ca(2+) uptake, indicating that the effect of 1,25D(3) may also result from Na(+)/K(+)-ATPase inhibition. In addition, we demonstrated that the mechanism underlying the hormone action involved extracellular signal-regulated kinase (ERK) and protein kinase C (PKC) activation in a phospholipase C-independent way. Furthermore, a local elevation of the level of cAMP, as demonstrated by incubating cells with dibutyryl cAMP or a phosphodiesterase inhibitor, produced an effect similar to that of 1,25D(3), and the inhibition of protein kinase A (PKA) nullified the hormone action. In conclusion, the stimulatory effect of 1,25D(3) on (45)Ca(2+) uptake in Sertoli cells occurs via VDCC, as well as PKA, PKC, and ERK activation. These protein kinases seem to act by inhibiting Na(+)/K(+)-ATPase or directly phosphorylating calcium channels. The Na(+)/K(+)-ATPase inhibition may result in Na(+)/Ca(2+) exchanger activation in reverse mode and consequently induce the uptake of calcium into the cells. 相似文献