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Wild Primate Populations in Emerging Infectious Disease Research: The Missing Link?
Wild primate populations, an unexplored source of information regarding emerging infectious disease, may hold valuable clues to the origins and evolution of some important pathogens. Primates can act as reservoirs for human pathogens. As members of biologically diverse habitats, they serve as sentinels for surveillance of emerging pathogens and provide models for basic research on natural transmission dynamics. Since emerging infectious diseases also pose serious threats to endangered and threatened primate species, studies of these diseases in primate populations can benefit conservation efforts and may provide the missing link between laboratory studies and the well-recognized needs of early disease detection, identification, and surveillance
PSMA, EpCAM, VEGF and GRPR as Imaging Targets in Locally Recurrent Prostate Cancer after Radiotherapy
In this retrospective pilot study, the expression of the prostate-specific membrane antigen (PSMA), the epithelial cell adhesion molecule (EpCAM), the vascular endothelial growth factor (VEGF) and the gastrin-releasing peptide receptor (GRPR) in locally recurrent prostate cancer after brachytherapy or external beam radiotherapy (EBRT) was investigated, and their adequacy for targeted imaging was analyzed. Prostate cancer specimens were collected of 17 patients who underwent salvage prostatectomy because of locally recurrent prostate cancer after brachytherapy or EBRT. Immunohistochemistry was performed. A pathologist scored the immunoreactivity in prostate cancer and stroma. Staining for PSMA was seen in 100% (17/17), EpCAM in 82.3% (14/17), VEGF in 82.3% (14/17) and GRPR in 100% (17/17) of prostate cancer specimens. Staining for PSMA, EpCAM and VEGF was seen in 0% (0/17) and for GRPR in 100% (17/17) of the specimens’ stromal compartments. In 11.8% (2/17) of cases, the GRPR staining intensity of prostate cancer was higher than stroma, while in 88.2% (15/17), the staining was equal. Based on the absence of stromal staining, PSMA, EpCAM and VEGF show high tumor distinctiveness. Therefore, PSMA, EpCAM and VEGF can be used as targets for the bioimaging of recurrent prostate cancer after EBRT to exclude metastatic disease and/or to plan local salvage therapy
Distribuição espacial de plantas daninhas resistentes a herbicidas no Brasil.
A ocorrência de plantas daninhas resistentes a herbicidas no Brasil tem sido um grande problema para os agricultores. O uso continuado de um mesmo herbicida resulta na seleção de biótipos resistentes ao princípio ativo e torna o manejo de plantas daninhas mais difícil, o que, por sua vez, pode gerar redução de produtividade. A confirmação da resistência demanda estudos em condições controladas, cujos resultados são divulgados em literatura especializada. Este trabalho teve por objetivo iniciar um levantamento de ocorrências comprovadas de plantas daninhas resistentes a herbicidas no Brasil, para posterior espacialização. Os trabalhos se iniciaram pela mais importante publicação nessa área, a revista Plantas Daninhas, da Sociedade Brasileira de Ciência das Plantas Daninhas, e abrangeram o período de 2000 a 2018. Foram publicados 36 artigos que descreviam plantas daninhas resistentes a herbicidas. As informações contidas nos artigos foram usadas para compor uma base de dados contendo informações sobre as plantas, os princípios ativos, o fator de resistência, os grupos de pesquisa, dados geográficos e agronômicos. Nesses artigos foram descritos 145 biótipos de plantas daninhas resistentes, pertencentes a 22 espécies e 12 gêneros. Os relatos descrevem a resistência a 14 princípios ativos. O herbicida mais frequente foi o glifosato, com 63 descrições. A maior parte dos biótipos resistentes foi encontrada no estado do Paraná, em seguida no Rio Grande do Sul, ocorrendo 68 e 50 relatos, respectivamente. Isso se deve, parcialmente, ao maior esforço de pesquisa realizado nesses estados
Gauging the SU(2) Skyrme model
In this paper the SU(2) Skyrme model will be reformulated as a gauge theory
and the hidden symmetry will be investigated and explored in the energy
spectrum computation. To this end we purpose a new constraint conversion
scheme, based on the symplectic framework with the introduction of Wess-Zumino
(WZ) terms in an unambiguous way. It is a positive feature not present on the
BFFT constraint conversion. The Dirac's procedure for the first-class
constraints is employed to quantize this gauge invariant nonlinear system and
the energy spectrum is computed. The finding out shows the power of the
symplectic gauge-invariant formalism when compared with another constraint
conversion procedures present on the literature.Comment: revised version, to appear in Phys.Rev.
Excitation of Magnetic Dipole Transitions at Optical Frequencies
We use the magnetic field distribution of an azimuthally polarized focused laser beam to excite a magnetic dipole transition in Eu3+ ions embedded in a Y2O3 nanoparticle. The absence of the electric field at the focus of an azimuthally polarized beam allows us to unambiguously demonstrate that the nanoparticle is excited by the magnetic dipole transition near 527.5 nm. When the laser wavelength is resonant with the magnetic dipole transition, the nanoparticle maps the local magnetic field distribution, whereas when the laser wavelength is resonant with an electric dipole transition, the nanoparticle is sensitive to the local electric field. Hence, by tuning the excitation wavelength, we can selectively excite magnetic or electric dipole transitions through optical fields
Two nonrecombining sympatric forms of the human malaria parasite Plasmodium ovale occur globally.
BACKGROUND: Malaria in humans is caused by apicomplexan parasites belonging to 5 species of the genus Plasmodium. Infections with Plasmodium ovale are widely distributed but rarely investigated, and the resulting burden of disease is not known. Dimorphism in defined genes has led to P. ovale parasites being divided into classic and variant types. We hypothesized that these dimorphs represent distinct parasite species. METHODS: Multilocus sequence analysis of 6 genetic characters was carried out among 55 isolates from 12 African and 3 Asia-Pacific countries. RESULTS: Each genetic character displayed complete dimorphism and segregated perfectly between the 2 types. Both types were identified in samples from Ghana, Nigeria, São Tomé, Sierra Leone, and Uganda and have been described previously in Myanmar. Splitting of the 2 lineages is estimated to have occurred between 1.0 and 3.5 million years ago in hominid hosts. CONCLUSIONS: We propose that P. ovale comprises 2 nonrecombining species that are sympatric in Africa and Asia. We speculate on possible scenarios that could have led to this speciation. Furthermore, the relatively high frequency of imported cases of symptomatic P. ovale infection in the United Kingdom suggests that the morbidity caused by ovale malaria has been underestimated
Storage methods, phenolic composition, and bioactive properties of Apis mellifera and Trigona spinipes pollen
The aim of this study was to evaluate the influence of lyophilization and drying in stove on phenolic compounds content
and the biological activity of Apis mellifera and Trigona spinipes pollens produced in Brazil. In general, the bee pollen produced
by T. spinipes presented highest antioxidant activity in dried and fresh samples assessed either by test of plasma
ferric reduction capacity (FRAP) and free radical scavenging assay (DPPH) methods. For A. mellifera bee pollen the antioxidant
activity was higher on the fresh samples. Nevertheless, b-carotene bleaching assay (BCB) and linoleic acid content
were higher in T. spinipes samples, mainly in the fresh ones. Higher antioxidant activity was owing to higher
content in phenolic compounds. Lyophilization method was the best for phenolic compounds’ conservation for both
species. The bee pollen of both species has a high amount of flavonoids: kaempferol-3-O-glucoside was the most abundant
in A. mellifera while for T. spinipes the most prevalent was resorcylic acidþepicatechin. All extracts presented antibacterial
activity against Saphylococcus aureus (ATCC 43300)TM, (ESA 83138150), (ESA 32), Pseudomonas aeruginosa
(ATCC 15442)TM, Pseudomonas aeruginosa (MRC.4) and (MRC.10). The methods used for storage influenced the biological
properties of bee pollen from both species. Regarding the content of phenolic compounds, differences were
observed amongst the pollen types: for A. mellifera these were best preserved with lyophilization, while for T. spinipes
the three storage methods were equivalent.The authors are grateful to the Coordenac¸~ao de
Aperfeic¸oamento de Pessoal de N ıvel Superior – CAPES
(88881.062167/2014-01 for M.L.M.E.). A. Pascoal would like to
thank Foundation for Science and Technology (FCT, Portugal),
Programa Operacional Potencial Humano (POPH), and
European Union (EU) for his Postdoctoral grant SFRH/BPD/
91380/2012.info:eu-repo/semantics/publishedVersio
Operatorial quantization of Born-Infeld Skyrmion model and hidden symmetries
The SU(2) collective coordinates expansion of the Born-Infeld\break Skyrmion
Lagrangian is performed. The classical Hamiltonian is computed from this
special Lagrangian in approximative way: it is derived from the expansion of
this non-polynomial Lagrangian up to second-order variable in the collective
coordinates. This second-class constrained model is quantized by Dirac
Hamiltonian method and symplectic formalism. Although it is not expected to
find symmetries on second-class systems, a hidden symmetry is disclosed by
formulating the Born-Infeld Skyrmion %model as a gauge theory. To this end we
developed a new constraint conversion technique based on the symplectic
formalism. Finally, a discussion on the role played by the hidden symmetry on
the computation of the energy spectrum is presented.Comment: A new version of hep-th/9901133. To appear in JP
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