106 research outputs found
An entomoepidemiological investigation of Chagas disease in the state of Ceará, Northeast Region of Brazil
Circumstellar disks and planets. Science cases for next-generation optical/infrared long-baseline interferometers
We present a review of the interplay between the evolution of circumstellar
disks and the formation of planets, both from the perspective of theoretical
models and dedicated observations. Based on this, we identify and discuss
fundamental questions concerning the formation and evolution of circumstellar
disks and planets which can be addressed in the near future with optical and
infrared long-baseline interferometers. Furthermore, the importance of
complementary observations with long-baseline (sub)millimeter interferometers
and high-sensitivity infrared observatories is outlined.Comment: 83 pages; Accepted for publication in "Astronomy and Astrophysics
Review"; The final publication is available at http://www.springerlink.co
Aspects of peridomiciliary ecotopes in rural areas of Northeastern Brazil associated to triatomine (Hemiptera, Reduviidae) infestation, vectors of Chagas disease
Cotton Rats (Sigmodon hispidus) and Black Rats (Rattus rattus) as Possible Reservoirs of Leishmania spp. in Lara State, Venezuela
Optical imaging of the peri-tumoral inflammatory response in breast cancer
<p>Abstract</p> <p>Purpose</p> <p>Peri-tumoral inflammation is a common tumor response that plays a central role in tumor invasion and metastasis, and inflammatory cell recruitment is essential to this process. The purpose of this study was to determine whether injected fluorescently-labeled monocytes accumulate within murine breast tumors and are visible with optical imaging.</p> <p>Materials and methods</p> <p>Murine monocytes were labeled with the fluorescent dye DiD and subsequently injected intravenously into 6 transgenic MMTV-PymT tumor-bearing mice and 6 FVB/n control mice without tumors. Optical imaging (OI) was performed before and after cell injection. Ratios of post-injection to pre-injection fluorescent signal intensity of the tumors (MMTV-PymT mice) and mammary tissue (FVB/n controls) were calculated and statistically compared.</p> <p>Results</p> <p>MMTV-PymT breast tumors had an average post/pre signal intensity ratio of 1.8+/- 0.2 (range 1.1-2.7). Control mammary tissue had an average post/pre signal intensity ratio of 1.1 +/- 0.1 (range, 0.4 to 1.4). The p-value for the difference between the ratios was less than 0.05. Confocal fluorescence microscopy confirmed the presence of DiD-labeled cells within the breast tumors.</p> <p>Conclusion</p> <p>Murine monocytes accumulate at the site of breast cancer development in this transgenic model, providing evidence that peri-tumoral inflammatory cell recruitment can be evaluated non-invasively using optical imaging.</p
CD8+ T-Cells Expressing Interferon Gamma or Perforin Play Antagonistic Roles in Heart Injury in Experimental Trypanosoma Cruzi-Elicited Cardiomyopathy
In Chagas disease, CD8+ T-cells are critical for the control of Trypanosoma cruzi during acute infection. Conversely, CD8+ T-cell accumulation in the myocardium during chronic infection may cause tissue injury leading to chronic chagasic cardiomyopathy (CCC). Here we explored the role of CD8+ T-cells in T. cruzi-elicited heart injury in C57BL/6 mice infected with the Colombian strain. Cardiomyocyte lesion evaluated by creatine kinase-MB isoenzyme activity levels in the serum and electrical abnormalities revealed by electrocardiogram were not associated with the intensity of heart parasitism and myocarditis in the chronic infection. Further, there was no association between heart injury and systemic anti-T. cruzi CD8+ T-cell capacity to produce interferon-gamma (IFNγ) and to perform specific cytotoxicity. Heart injury, however, paralleled accumulation of anti-T. cruzi cells in the cardiac tissue. In T. cruzi infection, most of the CD8+ T-cells segregated into IFNγ+ perforin (Pfn)neg or IFNγnegPfn+ cell populations. Colonization of the cardiac tissue by anti-T. cruzi CD8+Pfn+ cells paralleled the worsening of CCC. The adoptive cell transfer to T. cruzi-infected cd8−/− recipients showed that the CD8+ cells from infected ifnγ−/−pfn+/+ donors migrate towards the cardiac tissue to a greater extent and caused a more severe cardiomyocyte lesion than CD8+ cells from ifnγ+/+pfn−/− donors. Moreover, the reconstitution of naïve cd8−/− mice with CD8+ cells from naïve ifnγ+/+pfn−/− donors ameliorated T. cruzi-elicited heart injury paralleled IFNγ+ cells accumulation, whereas reconstitution with CD8+ cells from naïve ifnγ−/−pfn+/+ donors led to an aggravation of the cardiomyocyte lesion, which was associated with the accumulation of Pfn+ cells in the cardiac tissue. Our data support a possible antagonist effect of CD8+Pfn+ and CD8+IFNγ+ cells during CCC. CD8+IFNγ+ cells may exert a beneficial role, whereas CD8+Pfn+ may play a detrimental role in T. cruzi-elicited heart injury
FIRST CASE OF AUTOCHTHONOUS HUMAN VISCERAL LEISHMANIASIS IN THE URBAN CENTER OF RIO DE JANEIRO: CASE REPORT
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