Amitriptyline aggravates the fibrosis process in a rat model of infravesical obstruction

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Low intensity laser therapy (LILT) in vivo acts on the neutrophils recruitment and chemokines/cytokines levels in a model of acute pulmonary inflammation induced by aerosol of lipopolysaccharide from Escherichia coli in rat

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Recovery of pulmonary structure and exercise capacity by treatment with granulocyte-colony stimulating factor (G-CSF) in a mouse model of emphysema

Emphysema is a chronic obstructive pulmonary disease characterized abnormal dilatation of alveolar spaces, which impairs alveolar gas exchange, compromising the physical capacity of a patient due to airflow limitations. Here we tested the effects of G-CSF administration in pulmonary tissue and exercise capacity in emphysematous mice. C57Bl/6 female mice were treated with elastase intratracheally to induce emphysema. Their exercise capacities were evaluated in a treadmill. Lung histological sections were prepared to evaluate mean linear intercept measurement. Emphysematous mice were treated with G-CSF (3 cycles of 200 μg/kg/day for 5 consecutive days, with 7-day intervals) or saline and submitted to a third evaluation 8 weeks after treatment. Values of run distance and linear intercept measurement were expressed as mean ± SD and compared applying a paired t-test. Effects of treatment on these parameters were analyzed applying a Repeated Measures ANOVA, followed by Tukey's post hoc analysis. p < 0.05 was considered statistically significant. Twenty eight days later, animals ran significantly less in a treadmill compared to normal mice (549.7 ± 181.2 m and 821.7 ± 131.3 m, respectively; p < 0.01). Treatment with G-CSF significantly increased the exercise capacity of emphysematous mice (719.6 ± 200.5 m), whereas saline treatment had no effect on distance run (595.8 ± 178.5 m). The PCR cytokines genes analysis did not detect difference between experimental groups. Morphometric analyses in the lung showed that saline-treated mice had a mean linear intercept significantly higher (p < 0.01) when compared to mice treated with G-CSF, which did not significantly differ from that of normal mice. Treatment with G-CSF promoted the recovery of exercise capacity and regeneration of alveolar structural alterations in emphysematous mice. © 2013.

Low level laser therapy increases angiogenesis in a model of ischemic skin flap in rats mediated by VEGF, HIF-1α and MMP-2

It is known that low level laser therapy is able to improve skin flap viability by increasing angiogenesis. However, the mechanism for new blood vessel formation is not completely understood. Here, we investigated the effects of 660 nm and 780 nm lasers at fluences of 30 and 40 J/cm2 on three important mediators activated during angiogenesis. Sixty male Wistar rats were used and randomly divided into five groups with twelve animals each. Groups were distributed as follows: skin flap surgery non-irradiated group as a control; skin flap surgery irradiated with 660 nm laser at a fluence of 30 or 40 J/cm2 and skin flap surgery irradiated with 780 nm laser at a fluence of 30 or 40 J/cm2. The random skin flap was performed measuring 10 × 4 cm, with a plastic sheet interposed between the flap and the donor site. Laser irradiation was performed on 24 points covering the flap and surrounding skin immediately after the surgery and for 7 consecutive days thereafter. Tissues were collected, and the number of vessels, angiogenesis markers (vascular endothelial growth factor, VEGF and hypoxia inducible factor, HIF-1α) and a tissue remodeling marker (matrix metalloproteinase, MMP-2) were analyzed. LLLT increased an angiogenesis, HIF-1α and VEGF expression and decrease MMP-2 activity. These phenomena were dependent on the fluences, and wavelengths used. In this study we showed that LLLT may improve the healing of skin flaps by enhancing the amount of new vessels formed in the tissue. Both 660 nm and 780 nm lasers were able to modulate VEGF secretion, MMP-2 activity and HIF-1α expression in a dose dependent manner. © 2013 Published by Elsevier B.V.

Light-front model of the kaon electromagnetic current

The kaon electromagnetic form factor is extracted from both components of the current: J(+) and J(-) with a pseudo-scalar coupling of the quarks to the meson. The pair production process does not contribute to J(+) in the Drell-Yan frame (q(+) = 0). However, the pair production process contribution is different from zero in J(-) and this contribution is necessary to keep the rotational symmetry properties of the current.

Positronium-hydrogen-atom scattering in a five-state model

The scattering of orthopositronium (Ps) by hydrogen atoms has been investigated in a five-state coupled-channel model allowing for Ps(1s)H(2s,2p) and Ps(2s,2p)H(1s) excitations using a recently proposed electron-exchange model potential. The higher (n greater than or equal to 3) excitations and ionization of the Ps atom are calculated using the first Born approximation. Calculations are reported of scattering lengths, phase shifts. elastic, Ps and H excitation, and total cross sections. Remarkable correlations are observed between the S-wave Ps-H binding energy and the singlet scattering length, effective range, and resonance energy obtained in various model calculations. These correlations suggest that if a Ps-H dynamical model yields the correct result for one of these four observables, it is expected to lead to the correct result for the other three. The present model, which is constructed so as to reproduce the Ps-H resonance at 4.01 eV, automatically yields a Ps-H bound state at - 1.05 eV that compares well with the accurate value of - 1.067 eV. The model leads to a singlet scattering length of 3.72a(0) and effective range of 1.67a(0), whereas the correlations suggest the precise values of 3.50a(0) and 1.65a(0) for these observables, respectively. [S1050-2947(99)07703-3].

Light-Front model of transition form-factors in heavy meson decay

Electroweak transition form factors of heavy meson decays are important ingredients in the extraction of the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements from experimental data. In this work, within a. light-front framework, we calculate electroweak transition form factor for the semileptonic decay of D mesons into a pion or a kaon. The model results underestimate in both cases the new data of CLEO for the larger momentum transfers accessible in the experiment. We discuss possible reasons for that in order to improve the model.

Traços de personalidade e habilidades sociais em universitários

O presente estudo teve como objetivo analisar as relações entre habilidades sociais e traços de personalidade englobados por socialização, no modelo dos Cinco Grandes Fatores. O Inventário de Habilidades Sociais (IHS) foi utilizado para a mensuração de habilidades sociais, e para avaliação do nível de socialização foi escolhida a Escala Fatorial de Socialização (EFS). A amostra foi composta por 126 estudantes universitários com média de idade de 21 anos (DP=3,37), e 53,5% eram homens. Os resultados da IHS e EFS foram comparados para os sexos, encontrando-se diferenças estatisticamente significativas para seis das dez medidas realizadas no estudo. Foram encontradas correlações significativas entre amabilidade, auto-afirmação e o total do IHS. Pró-sociabilidade correlacionou-se com auto-afirmação e autocontrole. Confiança nas pessoas apresentou correlações significativas com enfrentamento, auto-afirmação e autocontrole. Os resultados indicam que, efetivamente, a personalidade pode influenciar diferentes aspectos da habilidade social.

Chloroquine is therapeutic in murine experimental model of paracoccidioidomycosis

Chloroquine, due to its basic properties, has been shown to prevent the release of iron from holotransferrin, thereby interfering with normal iron metabolism in a variety of cell types. We have studied the effects of chloroquine on the evolution of experimental paracoccidioidomycosis by evaluating the viable fungal recovery from lung, liver and spleen from infected mice and H2O2, NO production, tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-6, IL-10 levels and transferrin receptor (TfR) expression from uninfected and infected peritoneal macrophages. Chloroquine caused a significant decrease in the viable fungal recovery from all organs tested, during all periods of evaluation. Peritoneal macrophages from chloroquine-treated infected mice showed higher H2O2 production and TfR expression, and decreased levels of NO, endogenous and stimulated-TNF-alpha, IL-6 and IL-10 during the three evaluated periods. However, despite its suppressor effects on the macrophage function, the chloroquine therapeutic effect upon murine paracoccidioidomycosis was probably due to its effect on iron metabolism, blocking iron uptake by cells, and consequently restricting iron to fungus growth and survival.

Obesity enhances eosinophilic inflammation in a murine model of allergic asthma

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Pro-inflammatory cytokines predominate in the brains of dogs with visceral leishmaniasis: A natural model of neuroinflammation during systemic parasitic infection

Visceral leishmaniasis is a multisystemic zoonotic disease that can manifest with several symptoms, including neurological disorders. To investigate the pathogenesis of brain alterations occurring during visceral leishmaniasis infection, the expression of the cytokines IL-1β, IL-6, IL-10, IL-12p40, IFN-γ, TGF-β and TNF-α and their correlations with peripheral parasite load were evaluated in the brains of dogs naturally infected with Leishmania infantum. IL-1β, IFN-γ and TNF-α were noticeably up-regulated, and IL-10, TGF-β and IL-12p40 were down-regulated in the brains of infected dogs. Expression levels did not correlate with parasite load suggestive that the brain alterations are due to the host's immune response regardless of the phase of the disease. These data indicate the presence of a pro-inflammatory status in the nervous milieu of dogs with visceral leishmaniasis especially because IL-1β and TNF-α are considered key factors for the initiation, maintenance and persistence of inflammation. © 2012 Elsevier B.V.

Curcumin-mediated photodynamic inactivation of Candida albicans in a murine model of oral candidiasis

In vitro investigations of curcumin-mediated photodynamic therapy (PDT) are encouraging, but there is a lack of reliable in vivo evidence of its efficacy. This study describes the photoinactivation of Candida albicans in a murine model of oral candidiasis, using curcumin as a photosensitizer. Forty immunosuppressed mice were orally inoculated with C. albicans and after five days, they received topical curcumin (20, 40 and 80 μM) and illumination with LED light. The use of curcumin or light alone were also investigated. Positive control animals did not receive any treatment and negative control animals were not inoculated with C. albicans. The number of surviving yeast cells was determined and analyzed by ANOVA and Tukey's post-hoc test (α = 0.05). Histological evaluation of the presence of yeast and inflammatory reaction was also conducted. All exposures to curcumin with LED light caused a significant reduction in C. albicans viability after PDT, but the use of 80 μM curcumin associated with light was able to induce the highest log10 reduction in colony counts (4 logs). It was concluded that curcumin-mediated PDT proved to be effective for in vivo inactivation of C. albicans without harming the host tissue of mice. © 2013 ISHAM.

Mechanism and effect of esculetin in an experimental animal model of inflammatory bowel disease

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morphologic and biomechanical changes of thoracic and abdominal aorta in a rat model of cigarette smoke exposure

Background: Smoking is the most relevant environmental factor that affects the development of aortic aneurysm. Smokers have elevated levels of elastase activity in the arterial wall, which leads to weakening of the aorta. The aim of this study was to verify whether cigarette smoke exposure itself is capable of altering the aortic wall. Methods: Forty-eight Wistar rats were divided into 2-, 4-, and 6-month experimental periods and into 2 groups: smokers (submitted to smoke exposure at a rate of 40 cigarettes/day) and nonsmokers. At the end of the experimental periods, the aortas were removed and cross-sectioned to obtain histologic specimens for light microscopic and morphometric analyses. The remaining longitudinal segments were stretched to rupture and mechanical parameters were determined. Results: A degenerative process (i.e., a reduction in elastic fibers, the loss of lamellar arrangement, and a reduction of smooth muscle cells) was observed, and this effect was proportional in intensity to the period of tobacco exposure. We observed a progressive reduction in the yield point of the thoracic aorta over time (P < 0.05). There was a decrease in stiffness (P < 0.05) and in failure load (P < 0.05) at 6 months in the abdominal aorta of rats in the smoking group. Conclusions: Chronic exposure to tobacco smoke can affect the mechanical properties of the aorta and can also provoke substantial structural changes of the arterial wall. © 2013 Elsevier Inc. All rights reserved.

Effect of melatonin on tumor growth and angiogenesis in xenograft model of breast cancer

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)