Pontos de carbono luminescentes à base de ovalbumina aplicados em marcação biológica

Entre os nanomateriais de carbono, os pontos de carbono (PCs) estão entre os mais atraentes devido as suas interessantes propriedades fotoluminescentes. Os PCs apresentam processo de síntese fácil, possibilidade de funcionalização da superfície, baixa toxicidade, alta solubilidade em água e biocompatibilidade. Devido a isso, suas aplicações na área biomédica e de bioimagem tem se destacado na literatura. Neste trabalho, PCs foram sintetizados por dois métodos diferentes a partir da ovalbumina, o qual é um precursor não tóxico e composto predominantemente por aminoácidos de cadeia curta. Os PCs foram caracterizados por espectroscopias de absorção (UV-Vis), de emissão (fluorescência) e infravermelho (IVTF), além de análise termogravimétrica (ATG). Os PCs foram utilizados como sondas fluorescentes para uma imagem colorida (azul e verde) de células HEK293 e não induziram a morte celular, o que indica que os mesmos são biocompatíveis e não tóxicos para este tipo de células. Dessa forma, os resultados aqui apresentados demonstram que os PCs podem ser considerados potenciais substitutos para corantes comerciais em marcação biológica.Palavras-chave: nanopartículas de carbono, fotoluminescência, biocompatibilidade, HEK293.

Intravenous human umbilical cord-derived mesenchymal stromal cell administration in models of moderate and severe intracerebral hemorrhage

Intracerebral hemorrhage (ICH) is as a life-threatening condition that can occur in young adults, often causing long-term disability. Recent preclinical data suggests mesenchymal stromal cell (MSC)-based therapies as promising options to minimize brain damage after ICH. However, therapeutic evidence and mechanistic insights are still limited, particularly when compared to other disorders such as ischemic stroke. Herein, we employed a model of collagenase-induced ICH in young adult rats to investigate the potential therapeutic effects of an intravenous injection of human umbilical cord Wharton's jelly-derived MSCs (hUC-MSCs). Two doses of collagenase were used to cause moderate or severe hemorrhages. Magnetic resonance imaging showed that animals treated with hUC-MSCs after moderate ICH had smaller residual hematoma volumes than vehicle-treated rats, whereas the cell therapy failed to decrease the hematoma volume in animals with a severe ICH. Functional assessments (rotarod and elevated body swing tests) were performed for up to 21 days after ICH. Enduring neurological impairments were seen only in animals subjected to severe ICH, but the cell therapy did not induce statistically significant improvements in the functional recovery. The biodistribution of Technetium-99m-labeled hUC-MSCs was also evaluated, showing that most cells were found in organs such as the spleen and lungs 24 h after transplantation. Nevertheless, it was possible to detect a weak signal in the brain, which was higher in the ipsilateral hemisphere of rats subjected to a severe ICH. These data indicate that hUC-MSCs have moderately beneficial effects in cases of less severe brain hemorrhages in rats by decreasing the residual hematoma volume, and that optimization of the therapy is still necessary

Survey of Third-Party Parenting Options Associated With Fertility Preservation Available to Patients With Cancer Around the Globe

Purpose: In the accompanying article, “Analysis of Fertility Preservation Options Available to Patients With Cancer Around the Globe,” we showed that specific fertility preservation services may not be offered at various sites around the world because of cultural and legal barriers. We assessed global and regional experiences as well as the legal status of third-party reproduction and adoption to serve as a comprehensive international data set and resource for groups that wish to begin oncofertility interventions. Methods: We provide data on the legalities of third-party assisted reproductive technologies and other family-building options in the 28 oncofertility-practicing countries surveyed. Results: We found regional and country differences that will be important in the development of tailored resources for physicians and for patient brochures that are sensitive to these local restrictions and cultural norms. Conclusion: Because many patients first consult Web-based materials, the formal assessment of the availability of these options provides members of the global oncofertility community with data to which they might otherwise not have ready access to better serve their patients

Survey of third-party parenting options associated with fertility preservation available to patients with cancer around the globe

bstract PURPOSE In the accompanying article, “Survey of Fertility Preservation Options Available to Patients With Cancer Around the Globe,” we showed that specific fertility preservation services may not be offered at various sites around the world because of cultural and legal barriers. We assessed global and regional experiences as well as the legal status of third-party reproduction and adoption to serve as a comprehensive international data set and resource for groups that wish to begin oncofertility interventions. METHODS We provide data on the legalities of third-party assisted reproductive technologies and other familybuilding options in the 28 oncofertility-practicing countries surveyed. RESULTS We found regional and country differences that will be important in the development of tailored resources for physicians and for patient brochures that are sensitive to these local restrictions and cultural norms. CONCLUSION Because many patients first consult Web-based materials, the formal assessment of the availability of these options provides members of the global oncofertility community with data to which they might otherwise not have ready access to better serve their patients

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Biologia e nicho de espermatogônias tronco em catetos (tayassu tajacu) adultos

Exportado OPUSMade available in DSpace on 2019-08-13T19:13:39Z (GMT). No. of bitstreams: 1 disserta_ao_paulo_ha_campos_junior.pdf: 2082556 bytes, checksum: 9254060ec006474cb2776cc8aa238269 (MD5) Previous issue date: 19No epitélio seminífero, as células tronco espermatogoniais (SSCs) apresentam-se localizadas em micro-ambientes específicos denominados nichos espermatogoniais, que são regulados pela membrana basal, células somáticas testiculares e fatores provenientes destas e dos vasos sangüíneos. No entanto, o exato papel das células de Leydig (CL) como componente do nicho espermatogonial permanece ainda desconhecido. Estudos recentemente desenvolvidos em nosso laboratório demonstraram que catetos (Tayassu tajacu) apresentam citoarquitetura peculiar das CL, na qual estas células envolvem lóbulos de túbulos seminíferos formando estruturas semelhantes a cordões celulares. Esta particularidade torna os catetos um modelo experimental ímpar para se investigar a biologia e nicho espermatogonial em mamíferos. Este aspecto peculiar permite também subdividir as secções transversais de túbulos seminíferos em três diferentes regiões: [túbulo-túbulo (T-T); túbulointerstício (T-I); e túbulo-CL (T=-L)]. Os objetivos do presente estudo foram os de se caracterizar os diferentes tipos espermatogoniais de catetos e determinar a localização e/ou distribuição das SSCs nos túbulos seminíferos desta espécie, utilizando diferentes abordagens metodológicas. Comparado com as espermatogônias em diferenciação (Adif), as espermatogônias indiferenciadas (Aund) apresentaram volume nuclear maior (p<0.05), o que permitiu uma acurada avaliação de sua distribuição. Análises deimunomarcações demonstraram que todas Aund expressam GFR1 que é o receptor de membrana para o GDNF (Glial cellderived neurotrophic factor) produzido pelas células de Sertoli. No entanto, principalmente as espermatogônias A isoladas (As) e A pareadas(Apr) apresentaram-se preferencialmente localizadas na região TI (p<0.05), enquanto clones espermatogoniais contendo 8 ou mais células (Aal) apresentaram-se principalmente na região T-CL (p<0.05). A expressão do CSF-1 (Colony stimulating factor -1 ) foi observada nas CL e células peritubulares mióides (CPM) enquanto seu receptor (CSF1r) foi observado nas CL e em todas as espermatogônias Aund GFR1+.Desta forma, estes resultados sugerem fortemente que, diferentemente das CPM, as CL atuam negativamente no nicho e fisiologia espermatogonial, e que estas células esteroidogênicas estão possivelmente envolvidas na diferenciação das espermatogônias Aund para A1.In the seminiferous epithelium, spermatogonial stem cells (SSCs) are located in a particular environment called niche that is controlled by the basement membrane, key testis somatic cells, and by factors emanating from the vascular network. However, the role of Leydig cells (LC) as a niche component is not yet clearly elucidated. Recent studies showed that peccaries (Tayassu tajacu) present a peculiar LC cytoarchitecture,where these cells are located around the seminiferous tubules lobes, making the peccary an unique model for investigating SSCs. This peculiarity allowed us to subdivide the seminiferous tubules cross-sections in three different regions [tubuletubule (T-T); tubule-interstitium (T-I); and tubule-LC contact (T-LC)]. Our aims were tocharacterize the different spermatogonial cell types in this species and to determine the location and/or distribution of the SSCs along the seminiferous tubules. Compared to differentiating spermatogonia (Adiff), undifferentiated spermatogonia (Aund) presented a noticeably higher nuclear volume (p<0.05), allowing an accurate evaluation of their distribution. Immunostaining analysis demonstrated that all Aund (As,Apr and Aal) were GFRA1+. However, only A-single (As) and A-paired (Apr) spermatogonia were located in the T-I (p<0.05), whereas clones containing eight or more undifferentiated cells (Aal) were situated close to the T-LC (p<0.05). The expression of CSF-1 was observed in LC and peritubular myoid cells (PMC) while its receptor was present in LC and in GFRA1+ Aund. Taken together, our findings strongly suggest that, different from PMC, LC play a negative role in the SSC niche and physiology and that these steroidogenic cells are probably involved in the differentiation of Aund toward type A1 spermatogonia

Use of ultrasound biomicroscopy to evaluate induced ovarian follicular growth and ovulation in mice.

Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2014-11-27T16:48:21Z No. of bitstreams: 1 Campos J r P H A Use of ultrasound....pdf: 283319 bytes, checksum: 57e446f20b0b9f0ea96574bd03bc1690 (MD5)Approved for entry into archive by Ana Maria Fiscina Sampaio ([email protected]) on 2014-11-27T16:48:29Z (GMT) No. of bitstreams: 1 Campos J r P H A Use of ultrasound....pdf: 283319 bytes, checksum: 57e446f20b0b9f0ea96574bd03bc1690 (MD5)Made available in DSpace on 2014-11-27T17:08:27Z (GMT). No. of bitstreams: 1 Campos J r P H A Use of ultrasound....pdf: 283319 bytes, checksum: 57e446f20b0b9f0ea96574bd03bc1690 (MD5) Previous issue date: 2011Federal University of Minas Gerais. Belo Horizonte, MG, Brasil / Embrapa Dairy Cattle Research Center. Juiz de Fora, MG, BrasilBiotechnology and Cellular Therapy Center. Salvador, BA, Brasil / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilFederal University of Juiz de Fora. Juiz de Fora, MG, BrasilBiotechnology and Cellular Therapy Center. Salvador, BA, Brasil / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilBiotechnology and Cellular Therapy Center. Salvador, BA, Brasil / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilEmbrapa Dairy Cattle Research Center. Juiz de Fora, MG, BrasilRecent advances in image technology, including significant gains in spatial resolution, have made realtime sequential ovarian evaluations possible in small rodents, allowing longitudinal (continued) studies of the ovarian cycle and reducing the required number of experimental animals. The aim of this study was to evaluate exogenous stimulated follicular growth in mice using high-resolution ultrasound technology. Female mice (n ¼ 15) received a 5 IU intraperitoneal injection of equine chorionic gonadotropin (eCG) and 48 h later a 5 IU injection of human chorionic gonadotropin (hCG), and were allowed to mate thereafter. In experiment 1, animals (n ¼ 7) were evaluated every 6 h, from 3 to 51 h after eCG injection, with an ultrasound biomicroscopy (UBM) equipped with a realtime 45 MHz microvisualization probe (RMV 707b). The ovaries were identified and follicular population quantified, and follicles were classified according to the diameter as small ( 449 mm) or large ( 450 mm). A significant change in the distribution of follicle population according to category was observed only 45 h after eCG injection (P, 0.05). In experiment 2, animals (n ¼ 8) were evaluated every 2 h, from 2 h to 10 h after hCG treatment. The largest follicles reached a maximum size (596.7+106.0 mm) 5.8+2.3 h after hCG injection. As expected, the population of large follicles decreased thereafter, indicating the progress of ovulations, but large follicles were still detected late after treatment (10.1+1.1 h). In conclusion, UBM can be used to evaluate follicle dynamics in superstimulated mice (C57BL/6 and BALB/c); significant changes in follicle distribution only occur at later stages after eCG stimulation; and hCG-induced ovulations may not occur synchronously in mice