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1.
Science ; 384(6701): 1155, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38870292

RESUMO

Since 2001, the United Nations has designated 20 June as World Refugee Day. It seeks to raise awareness of refugees-currently estimated to be more than 114 million persons internally displaced, exiled, or on the move-and the often-harsh conditions they confront around the world. Among them are scientists, giving the scientific community a special responsibility to protect and support these colleagues. It is not just scientists and their families whose lives are disrupted, but science as an enterprise as well.

2.
Ear Hear ; 31(5): 714-21, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20539233

RESUMO

OBJECTIVE: Human mutations in the DNA repair genes, Xeroderma pigmentosum (XP)-C and XPA result in hearing loss, which has fueled the hypothesis that there is a significant demand for these genes in protecting cochlear genetic material. Therefore, we quantified the level of XPC and XPA mRNA in the mammalian cochlea. DESIGN: XPC and XPA mRNAs were purified from the cochlea of 15 Fischer344 rats and quantified using SYBR Green chemistry. Another 15 Fischer344 rats were sacrificed for immunolocalization of XPC and XPA polypeptides in the cochlea and kidney (control organ). RESULTS: XP mRNA levels were up to 95% (XPA) and 69% (XPC) of the respective maximum expression capacity of each gene. In addition, these cochlear levels were up to sixfold (XPC) and threefold (XPA) greater than that of the kidney, which is known to exhibit XP-DNA repair activity that is greater than most organs of the body. Immunohistochemistry revealed that most kidney and cochlear cells were immunopositive. CONCLUSION: These data suggest that under normal conditions the cochlea is experiencing persistent genomic stress that helps to explain the hypersensitivity of the cochlea to exogenous stressors (ototoxic xenobiotics and/or acoustic-overexposure) as well as provide a basis to interpret hearing loss among patients with XP.


Assuntos
Proteínas de Transporte/genética , Cóclea/fisiologia , Reparo do DNA/fisiologia , Proteínas de Ligação a DNA/genética , Animais , Proteínas de Transporte/metabolismo , Proteínas de Ligação a DNA/metabolismo , Expressão Gênica/fisiologia , Humanos , Imuno-Histoquímica , Rim/fisiologia , Mamíferos , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos F344
3.
Crit Rev Ther Drug Carrier Syst ; 34(1): 35-61, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28322140

RESUMO

Recent advances in nanotechnology have transformed the biomedicine field, in which the use of engineered nanomaterials (ENMs) has provided the foundation for novel applications. For this reason, the number of ENMs has increased rapidly, and here we provide a classification of ENMs based on chemical composition and biomedical applications, which include regenerative medicine, delivery systems, theranostics, and therapy. These have been identified as the most advanced and promising areas for further studies with humans. In addition, we discuss possible side effects related to ENM uses. We identify carbon, metal, and metal oxides as the most versatile ENM material groups, used in bone and neuronal regenerative medicine, thermal therapy, theranostics, drug delivery, gene therapy, and biosensors. However, the majority of drugs approved by the U.S. Food and Drug Administration (FDA) are lipid-based ENMs. We conclude that biomedical applications of ENMs offer potential benefits while side effects are mainly associated with occupational exposure. Finally, we suggest that in the future, nanocomposites, subnanometric structures, and biodegradable and biocorona formation could be used to improve the biomedical field by focusing on infectious diseases, early detection, and precision medicine.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Nanoestruturas/efeitos adversos , Nanoestruturas/uso terapêutico , Medicina Regenerativa/métodos , Nanomedicina Teranóstica/métodos , Animais , Sistemas de Liberação de Medicamentos/efeitos adversos , Humanos
4.
Int J Nanomedicine ; 9: 2031-41, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24790441

RESUMO

Nanomaterials are the subject of intense research, focused on their synthesis, modification, and biomedical applications. Increased nanomaterial production and their wide range of applications imply a higher risk of human and environmental exposure. Unfortunately, neither environmental effects nor toxicity of nanomaterials to organisms are fully understood. Cost-effective, rapid toxicity assays requiring minimal amounts of materials are needed to establish both their biomedical potential and environmental safety standards. Drosophila exemplifies an efficient and cost-effective model organism with a vast repertoire of in vivo tools and techniques, all with high-throughput scalability and screening feasibility throughout its life cycle. Here we report tissue specific nanomaterial assessment through direct microtransfer into target tissues. We tested several nanomaterials with potential biomedical applications such as single-wall carbon nanotubes, multiwall carbon nanotubes, silver, gold, titanium dioxide, and iron oxide nanoparticles. Assessment of nanomaterial toxicity was conducted by evaluating progression through developmental morphological milestones in Drosophila. This cost-effective assessment method is amenable to high-throughput screening.


Assuntos
Bioensaio/instrumentação , Drosophila melanogaster/efeitos dos fármacos , Drosophila melanogaster/embriologia , Microinjeções/instrumentação , Micromanipulação/instrumentação , Nanopartículas/toxicidade , Testes de Toxicidade/instrumentação , Animais , Drosophila melanogaster/fisiologia , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/fisiologia , Desenho de Equipamento , Análise de Falha de Equipamento , Nanopartículas/administração & dosagem
5.
CBE Life Sci Educ ; 12(3): 394-402, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24006388

RESUMO

Scientific workforce diversity is critical to ensuring the realization of our national research goals and minority-serving institutions play a vital role in preparing undergraduate students for science careers. This paper summarizes the outcomes of supporting career training and research practices by faculty from teaching-intensive, minority-serving institutions. Support of these faculty members is predicted to lead to: 1) increases in the numbers of refereed publications, 2) increases in federal grant funding, and 3) a positive impact on professional activities and curricular practices at their home institutions that support student training. The results presented show increased productivity is evident as early as 1 yr following completion of the program, with participants being more independently productive than their matched peers in key areas that serve as measures of academic success. These outcomes are consistent with the goals of the Visiting Professorship Program to enhance scientific practices impacting undergraduate student training. Furthermore, the outcomes demonstrate the benefits of training support for research activities at minority-serving institutions that can lead to increased engagement of students from diverse backgrounds. The practices and results presented demonstrate a successful generalizable approach for stimulating junior faculty development and can serve as a basis for long-term faculty career development strategies that support scientific workforce diversity.


Assuntos
Academias e Institutos , Comportamento Cooperativo , Docentes , Grupos Minoritários/educação , Competência Profissional , Pesquisa/educação , Academias e Institutos/economia , Etnicidade/educação , Etnicidade/estatística & dados numéricos , Humanos , Grupos Minoritários/estatística & dados numéricos , Modelos Educacionais , Publicações , Pesquisa/economia , Apoio à Pesquisa como Assunto/economia , Estudantes
6.
CBE Life Sci Educ ; 10(3): 287-97, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21885825

RESUMO

Today, more minority students are entering undergraduate programs than ever before, but they earn only 6% of all science or engineering PhDs awarded in the United States. Many studies suggest that hands-on research activities enhance students' interest in pursuing a research career. In this paper, we present a model for the implementation of laboratory research in the undergraduate teaching laboratory using a culturally relevant approach to engage students. Laboratory modules were implemented in upper-division genetics and cell biology courses using cassava as the central theme. Students were asked to bring cassava samples from their respective towns, which allowed them to compare their field-collected samples against known lineages from agricultural stations at the end of the implementation. Assessment of content and learning perceptions revealed that our novel approach allowed students to learn while engaged in characterizing Puerto Rican cassava. In two semesters, based on the percentage of students who answered correctly in the premodule assessment for content knowledge, there was an overall improvement of 66% and 55% at the end in the genetics course and 24% and 15% in the cell biology course. Our proposed pedagogical model enhances students' professional competitiveness by providing students with valuable research skills as they work on a problem to which they can relate.


Assuntos
Biologia Celular/educação , Cultura , Currículo , Genética/educação , Laboratórios , Ensino , DNA de Plantas/isolamento & purificação , Eletroforese em Gel de Ágar , Marcadores Genéticos , Conhecimento , Aprendizagem , Manihot/genética , Repetições de Microssatélites/genética , Raízes de Plantas/metabolismo , Estômatos de Plantas/metabolismo , Porto Rico , Amido/análise , Estudantes
7.
8.
J Biol Chem ; 280(8): 6496-503, 2005 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-15596439

RESUMO

Receptor-triggered control of local postsynaptic protein synthesis plays a crucial role for enabling long lasting changes in synaptic functions, but signaling pathways that link receptor stimulation with translational control remain poorly known. Among the putative regulatory factors are mRNA-binding proteins (messenger ribonucleoprotein, mRNP), which control the fate of cytosolic localized mRNAs. Based on the assumption that a subset of mRNA is maintained in an inactive state, mRNP-mRNA complexes were separated into polysome-bound (translated) and polysome-free (nontranslated) fractions by sucrose density centrifugation. Poly(A) mRNA-mRNP complexes were purified from a postmitochondrial extract of rat cerebral cortex by oligo(dT)-cellulose affinity chromatography. The mRNA processing proteins were characterized, from solution, by a nanoflow reverse phase-high pressure liquid chromatography-mu-electrospray ionization mass spectrometry. The majority of detected mRNA-binding proteins was found in both fractions. However, a small number of proteins appeared to be fraction-specific. This subset of proteins is by far the most interesting because the proteins are potentially involved in controlling an activity-dependent onset of translation. They include transducer proteins, kinases, and anchor proteins. This study of the mRNP proteome is the first step in allowing future experimentation to characterize individual proteins responsible for mRNA processing and translation in dendrites.


Assuntos
RNA Mensageiro/metabolismo , Ribonucleoproteínas/isolamento & purificação , Animais , Fracionamento Celular , Centrifugação com Gradiente de Concentração , Córtex Cerebral , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Substâncias Macromoleculares , Polirribossomos/metabolismo , Ligação Proteica , Biossíntese de Proteínas , Proteômica , RNA Mensageiro/isolamento & purificação , Ratos , Ratos Long-Evans , Ribonucleoproteínas/análise , Ribonucleoproteínas/metabolismo , Ribossomos/metabolismo , Espectrometria de Massas por Ionização por Electrospray
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