Acute effects of beta-blocker with intrinsic sympathomimetic activity on stress-induced cardiac dysfunction in rats

AbstractBackgroundWe have reported that α and β adrenergic blockers could protect against emotional stress-induced cardiac dysfunction but those protective effects of β adrenergic blockers with intrinsic sympathomimetic activity (ISA), such as celiprolol, are unknown. The purpose of this study is to evaluate whether ISA could relate with this protective effect.Methods and resultsRats medicated with celiprolol (8mg/kg), metoprolol (4mg/kg), or vehicle, were restrained for 30min (immobilization stress: IMO) to reproduce emotional stress, and anesthetized to release stress. We measured the fractional area change (FAC) using an echocardiography (SONOS5500) with s12 probe (frequency: 5–12MHz, frame rate: 120Hz) at the end of IMO and every 10min for 1h. During IMO, FAC in rats with a premedication of metoprolol was lower than in those with a premedication of vehicle or celiprolol. At 20min after IMO, FAC in rats with a premedication of celiprolol was significantly higher than that with a premedication of metoprolol or vehicle (84±9% vs. 65±3% or 60±7%, p<0.05). At 60min after IMO, FAC in rats with a premedication of vehicle or celiprolol recovered, but FAC in rats with a premedication of metoprolol did not.ConclusionAcute premedication with celiprolol could prevent a sudden drop of cardiac function after acute stress such as IMO. ISA might have an important role in preventing stress-induced cardiac dysfunction

Estratégia de leitura : língua japonesa como L2

Trabalho de Conclusão de Curso (graduação)—Universidade de Brasília, Instituto de Letras, Departamento de Línguas Estrangeiras e Tradução, Curso de Língua e Literatura Japonesa, 2013.O presente trabalho tem como tópico o uso de estratégias de compreensão leitora de textos de Língua Japonesa (LJ) como segunda língua (L2), apoiado nas principais teorias cognitivas de processamento de leitura: os métodos ascendente, descendente e interativo. Para tanto, este trabalho é delineado por um estudo de caso conduzido com 8 alunos da disciplina ‘Laboratório de Língua Japonesa’ do último semestre do curso de Licenciatura em LJ da Universidade de Brasília. A coleta de dados foi realizada através de um questionário misto contendo perguntas sobre o perfil do informante e as diferentes condutas durante a leitura. Para a análise, optou-se por agrupar a amostra de acordo com variáveis relativas ao tempo de contato com a LJ que, hipoteticamente, podem marcar a competência leitora; o tempo de estudo e a frequência leitora de textos nesta língua. Buscamos refletir sobre as diferentes estratégias leitoras e observar se existe distinção de comportamento entre os grupos. ___________________________________________________________________________ ABSTRACTThe present study focuses in the use of texts reading comprehension strategies in Japanese Language (LJ) as a second language, supported by the main cognitive theories of reading: bottom-up, top-down and interactive models. This work is outlined in a case study conducted with eight students in a discipline of the last semester of LJ Degree in the University of Brasilia. Data collection was performed through a mixed questionnaire containing questions about the profile of the informant and the different behaviors during reading. For analysis, we chose to group the sample according to variables related to the time contact with LJ that, hypothetically, may mark the reading competence; the study time and the reading frequency of texts in this language. We seek to reflect on the different reading strategies and see if there is difference in behavior between the groups

A Five-Year-Old Boy with Marked Hypergastrinemia Associated with H. pylori Infection

A 5-year-old boy was referred to our department for persistent epigastric discomfort. Serum gastrin level was 635 pg/ml with a pepsinogen (PG) I level of 102.7 ng/ml and a PG I/II ratio of 23.2, indicating a hyperacidic state. Upper gastrointestinal endoscopy showed normal gastric mucosal folds and no abnormalities including no gastric mucosal atrophy. To investigate the cause of hypergastrinemia, a Ca injection test was performed and the patient showed no definitive response to a large load of Ca. Contrast-enhanced dynamic CT revealed no space-occupying lesions. The results from these two studies were not consistent with the presence of gastrinoma. A urea breath test showed 2.8%, and a test for the fecal H. pylori antigen was positive. Since H. pylori infection was considered to be a possible cause of hypergastrinemia, eradication therapy was introduced. The therapy was shown to be successful by using a repeated urea breath test that showed a normalization to 0.6%. 7 months after the therapy blood examination showed a gastrin level of 191 pg/ml, a PG I level of 36.7 ng/ml, and a PG I/II ratio of 7.3. An immunostaining study of the gastric mucosa suggested that a decrease in somatostatin secretion due to a reduction in D cell population might have induced hypergastrinemia in this case. In children with H. pylori infection showing marked hypergastrinemia, immunohistochemical examination and therapeutic diagnosis by eradication may be helpful in the differential diagnosis of gastrinoma

Pathological study of pulmonary toxicity induced by intratracheally instilled Asian sand dust (Kosa): effects of lowered serum zinc level on the toxicity

Introduction. We have previously reported that Asian sand dust (ASD) induced acute and chronic inflammatory changes in the lung of mice. Zinc (Zn) is reported to influence inflammation and wound healing. The purpose of the study was to assess the effects of lowered serum Zn levels on the lung toxicity induced by ASD. Material and methods. Mice that were fed diets containing normal (group 1) or low (group 2) content of Zn for 8 weeks were intratracheally instilled with 3.0 mg of ASD, followed by sacrifice at 24 hours, 2 weeks, and 1, 2 and 3 months after instillation. Paraffin sections of lung tissues were stained by hematoxylin and eosin and by immunohistochemistry to detect tumor necrosis factor (TNF) and interleukin (IL)-1β as well as inflammasome (NALP3), autophagy (LC-3) and lysosome (LAMP-1) markers. Selected samples of lung tissue were examined by electron microscopy. Results. Following histological examination of the lung, similar patterns of inflammatory changes were observed in mice with normal and low serum Zn concentrations; however, they were more prominent and persistent in mice with low serum Zn level. These changes were both purulent (acute) and pyogranulomatous (chronic) in nature. In the lung lesions of group 2 mice the changes within the cytoplasmic vacuoles of enlarged ASD-containing macrophages (Mo) were clearly visible. The macrophages expressed TNF and IL-1β, and semi-quantitative analysis revealed a larger number of TNF-positive Mo in mice with normal level of serum Zn and a larger number of IL-1β-positive Mo in mice with low level of serum Zn. Decreased positive LC-3 staining and dilated lysosomes containing ASD particles were observed in the cytoplasm of Mo in mice with low serum Zn concentration. Conclusions. These findings suggest that low serum zinc concentration may induce the modulation of cytokine expression and lysosomal malfunction by phagocytotic and/or autophagic mechanisms, and may result in interstitial pyogranulomatous inflammation in the lungs of mice treated with ASD

Carbon Isotope and Isotopomer Fractionation in Cold Dense Cloud Cores

We construct the gas-grain chemical network model which includes carbon isotopes (12C and 13C) with an emphasis on isotopomer-exchange reactions. Temporal variations of molecular abundances, the carbon isotope ratios (12CX/13CX) and the isotopomer ratios (12C13CX/13C12CX) of CCH and CCS in cold dense cloud cores are investigated by numerical calculations. We confirm that the isotope ratios of molecules, both in the gas phase and grain surfaces, are significantly different depending on whether the molecule is formed from the carbon atom (ion) or the CO molecule. Molecules formed from carbon atoms have the CX/13CX ratios greater than the elemental abundance ratio of [12C/13C]. On the other hand, molecules formed from CO molecules have the CX/13CX ratios smaller than the [12C/13C] ratio. We reproduce the observed C13CH/13CCH ratio in TMC-1, if the isotopomer exchange reaction, 13CCH + H C13CH + H + 8.1 K, proceeds with the forward rate coefficient kf > 10^-11 cm3 s-1. However, the C13CS/13CCS ratio is lower than that observed in TMC-1. We then assume the isotopomer exchange reaction catalyzed by the H atom, 13CCS + H C13CS + H + 17.4 K. In the model with this reaction, we reproduce the observed C13CS/13CCS, CCS/C13CS and CCS/13CCS ratio simultaneously.Comment: 38 pages, 11 figures, 4 tables, accepted for publication in Astrophysical Journa

Comparative evaluations of lignocellulose reactivity and usability in transgenic rice plants with altered lignin composition

The aromatic composition of lignins is considered an important trait that affects the physico-chemical properties of lignocellulosic biomass. However, our knowledge of the relationship between lignin structure and biomass utilization properties remains limited, especially in monocotyledonous grass species, despite their potential as biomass feedstocks. In this study, we used recently produced rice transgenic lines with distinct lignin monomer compositions, i.e., guaiacyl (G)/syringyl (S)/p-hydroxyphenyl (H) aromatic unit ratios, to study the impact of lignin composition on the chemical reactivity, enzymatic saccharification efficiency and calorific value of rice lignocellulose. The H-lignin-enriched rice transgenic line showed significantly enhanced biomass saccharification efficiency after alkali and acid pretreatments and even without any pretreatment, whereas the S-lignin-enriched rice transgenic line displayed enhanced saccharification efficiency after liquid hot water pretreatment. While we detected no significant differences in biomass heating values between the transgenic rice materials tested, analysis of synthetic lignins comprising only G, S or H units suggested that increased ratios of G or H units could increase the heating value of lignin-based solid biofuels

Temperature and Field Dependence of the Energy Gap of MgB2/Pb planar junction

We have constructed MgB2/Pb planar junctions for both temperature and field dependence studies. Our results show that the small gap is a true bulk property of MgB2 superconductor, not due to surface effects. The temperature dependence of the energy gap manifests a nearly BCS-like behavior. Analysis of the effect of magnetic field on junctions suggests that the energy gap of MgB2 depends non-linearly on the magnetic field. Moreover, MgB2 has an upper critical field of 15 T, in agreement with some reported Hc2 from transport measurements.Comment: 5 pages, 5 figures. Submitted to Phys. Rev.

The Kiloparsec-scale Neutral Atomic Carbon Outflow in the Nearby Type-2 Seyfert Galaxy NGC 1068: Evidence for Negative AGN Feedback

Active galactic nucleus (AGN) feedback is postulated as a key mechanism for regulating star formation within galaxies. Studying the physical properties of the outflowing gas from AGN is thus crucial for understanding the co-evolution of galaxies and supermassive black holes. Here we report 55 pc resolution ALMA neutral atomic carbon [CI] $^3P_1\text{-}^3P_0$ observations toward the central 1 kpc of the nearby type-2 Seyfert galaxy NGC 1068, supplemented by 55 pc resolution CO($J=1\text{-}0$) observations. We find that [CI] emission within the central kpc is strongly enhanced by a factor of $>$5 compared to the typical [CI]/CO intensity ratio of $\sim$0.2 for nearby starburst galaxies (in units of brightness temperature). The most [CI]-enhanced gas (ratio $>$ 1) exhibits a kpc-scale elongated structure centered at the AGN that matches the known biconical ionized gas outflow entraining molecular gas in the disk. A truncated, decelerating bicone model explains well the kinematics of the elongated structure, indicating that the [CI] enhancement is predominantly driven by the interaction between the ISM in the disk and the highly inclined ionized gas outflow (which is likely driven by the radio jet). Our results strongly favor the "CO dissociation scenario" rather than the "in-situ C formation" one which prefers a perfect bicone geometry. We suggest that the high [CI]/CO intensity ratio gas in NGC 1068 directly traces ISM in the disk that is currently dissociated and entrained by the jet and the outflow, i.e., the "negative" effect of the AGN feedback.Comment: 12 pages, 5 figures, accepted for publication in The Astrophysical Journal Letter