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2.
Mol Biol Evol ; 38(9): 3864-3883, 2021 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-34426843

RESUMO

Dietary adaptation is a major feature of phenotypic and ecological diversification, yet the genetic basis of dietary shifts is poorly understood. Among mammals, Neotropical leaf-nosed bats (family Phyllostomidae) show unmatched diversity in diet; from a putative insectivorous ancestor, phyllostomids have radiated to specialize on diverse food sources including blood, nectar, and fruit. To assess whether dietary diversification in this group was accompanied by molecular adaptations for changing metabolic demands, we sequenced 89 transcriptomes across 58 species and combined these with published data to compare ∼13,000 protein coding genes across 66 species. We tested for positive selection on focal lineages, including those inferred to have undergone dietary shifts. Unexpectedly, we found a broad signature of positive selection in the ancestral phyllostomid branch, spanning genes implicated in the metabolism of all major macronutrients, yet few positively selected genes at the inferred switch to plantivory. Branches corresponding to blood- and nectar-based diets showed selection in loci underpinning nitrogenous waste excretion and glycolysis, respectively. Intriguingly, patterns of selection in metabolism genes were mirrored by those in loci implicated in craniofacial remodeling, a trait previously linked to phyllostomid dietary specialization. Finally, we show that the null model of the widely-used branch-site test is likely to be misspecified, with the implication that the test is too conservative and probably under-reports true cases of positive selection. Our findings point to a complex picture of adaptive radiation, in which the evolution of new dietary specializations has been facilitated by early adaptations combined with the generation of new genetic variation.


Assuntos
Metabolismo dos Carboidratos/genética , Quirópteros/genética , Dieta , Evolução Molecular , Seleção Genética , Adaptação Biológica/genética , Animais , Quirópteros/metabolismo , Comportamento Alimentar
3.
Regen Med ; 11(3): 287-305, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26979513

RESUMO

AIMS: Some allogeneic cell therapies requiring a high dose of cells for large indication groups demand a change in cell expansion technology, from planar units to microcarriers in single-use bioreactors for the market phase. The aim was to model the optimal timing for making this change. MATERIALS & METHODS: A development lifecycle cash flow framework was created to examine the implications of process changes to microcarrier cultures at different stages of a cell therapy's lifecycle. RESULTS: The analysis performed under assumptions used in the framework predicted that making this switch earlier in development is optimal from a total expected out-of-pocket cost perspective. From a risk-adjusted net present value view, switching at Phase I is economically competitive but a post-approval switch can offer the highest risk-adjusted net present value as the cost of switching is offset by initial market penetration with planar technologies. CONCLUSION: The framework can facilitate early decision-making during process development.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/economia , Custos e Análise de Custo , Avaliação Pré-Clínica de Medicamentos/economia , Modelos Econômicos , Transplante de Células-Tronco/economia , Células-Tronco , Aloenxertos , Humanos
4.
Stem Cell Reports ; 5(4): 647-59, 2015 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26411904

RESUMO

The discovery of induced pluripotent stem cells (iPSCs) and the concurrent development of protocols for their cell-type-specific differentiation have revolutionized our approach to cell therapy. It has now become critical to address the challenges related to the generation of iPSCs under current good manufacturing practice (cGMP) compliant conditions, including tissue sourcing, manufacturing, testing, and storage. Furthermore, regarding the technical challenges, it is very important to keep the costs of manufacturing and testing reasonable and solve logistic hurdles that permit the global distribution of these products. Here we describe our efforts to develop a process for the manufacturing of iPSC master cell banks (MCBs) under cGMPs and announce the availability of such banks.


Assuntos
Biotecnologia/métodos , Técnicas de Reprogramação Celular/métodos , Células-Tronco Pluripotentes Induzidas/citologia , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Linhagem Celular , Terapia Baseada em Transplante de Células e Tecidos , Marcação de Genes/métodos , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Transplante de Células-Tronco , Bancos de Tecidos
5.
Regen Med ; 10(5): 591-609, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26237703

RESUMO

AIM: To develop a decisional tool to identify the most cost effective process flowsheets for allogeneic cell therapies across a range of production scales. MATERIALS & METHODS: A bioprocess economics and optimization tool was built to assess competing cell expansion and downstream processing (DSP) technologies. RESULTS: Tangential flow filtration was generally more cost-effective for the lower cells/lot achieved in planar technologies and fluidized bed centrifugation became the only feasible option for handling large bioreactor outputs. DSP bottlenecks were observed at large commercial lot sizes requiring multiple large bioreactors. The DSP contribution to the cost of goods/dose ranged between 20-55%, and 50-80% for planar and bioreactor flowsheets, respectively. CONCLUSION: This analysis can facilitate early decision-making during process development.


Assuntos
Reatores Biológicos/economia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Tomada de Decisões , Medicina Regenerativa/economia , Técnicas de Cultura de Células , Proliferação de Células , Análise Custo-Benefício , Humanos , Indústrias , Células-Tronco Mesenquimais , Transplante de Células-Tronco/economia , Transplante Homólogo
6.
Biotechnol Bioeng ; 111(1): 69-83, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23893544

RESUMO

For allogeneic cell therapies to reach their therapeutic potential, challenges related to achieving scalable and robust manufacturing processes will need to be addressed. A particular challenge is producing lot-sizes capable of meeting commercial demands of up to 10(9) cells/dose for large patient numbers due to the current limitations of expansion technologies. This article describes the application of a decisional tool to identify the most cost-effective expansion technologies for different scales of production as well as current gaps in the technology capabilities for allogeneic cell therapy manufacture. The tool integrates bioprocess economics with optimization to assess the economic competitiveness of planar and microcarrier-based cell expansion technologies. Visualization methods were used to identify the production scales where planar technologies will cease to be cost-effective and where microcarrier-based bioreactors become the only option. The tool outputs also predict that for the industry to be sustainable for high demand scenarios, significant increases will likely be needed in the performance capabilities of microcarrier-based systems. These data are presented using a technology S-curve as well as windows of operation to identify the combination of cell productivities and scale of single-use bioreactors required to meet future lot sizes. The modeling insights can be used to identify where future R&D investment should be focused to improve the performance of the most promising technologies so that they become a robust and scalable option that enables the cell therapy industry reach commercially relevant lot sizes. The tool outputs can facilitate decision-making very early on in development and be used to predict, and better manage, the risk of process changes needed as products proceed through the development pathway.


Assuntos
Técnicas de Cultura de Células , Terapia Baseada em Transplante de Células e Tecidos , Células-Tronco/citologia , Transplante Homólogo , Algoritmos , Biotecnologia/economia , Biotecnologia/instrumentação , Biotecnologia/métodos , Técnicas de Cultura de Células/economia , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Humanos
7.
Pediatr Infect Dis J ; 32(1): 8-12, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23014358

RESUMO

BACKGROUND: Over 30 outbreaks of human salmonellosis linked to contact with live poultry from mail-order hatcheries were reported to Centers for Disease Control and Prevention between 1990 and 2010. In May 2009, we investigated an outbreak of human Salmonella Typhimurium infections, primarily affecting children. METHODS: A case was defined as a person with the outbreak strain of Salmonella Typhimurium, as determined by pulsed-field gel electrophoresis and multiple-locus variable-number tandem repeat analysis, in a Pennsylvania or New York resident with illness onset between May 1 and September 1, 2009. We conducted a case-control study to examine the relationship between illness and live poultry contact. Controls were age-matched and geographically-matched. Traceback and environmental investigations were conducted. RESULTS: We identified 36 case-patients in Pennsylvania and New York; 36% were children aged ≤5 years. Case-patients were more likely than controls to report live baby poultry contact (matched odds ratio [mOR]: 17.0; 95% confidence interval [CI]: 2.7-710.5), contact with chicks (mOR: 14.0; 95% CI: 2.1-592.0), ducklings (mOR: 8.0; 95% CI: 1.1-355.0) and visiting agricultural feed stores (mOR: 6.0; 95% CI: 1.3-55.2). Most (83%) visited agricultural Feed Store Chain Y, a national agricultural feed store chain, which received poultry from Hatchery C, which is supplied by multiple egg sources. Salmonella Typhimurium was isolated from a source duck flock, but had a different pulsed-field gel electrophoresis pattern than the outbreak strain. CONCLUSIONS: Live baby poultry remain an important source of human salmonellosis, particularly among children. Preventing these infections requires comprehensive interventions at hatcheries and agricultural feed stores; pediatricians should inform patients of risks associated with live poultry contact.


Assuntos
Surtos de Doenças , Patos , Salmonelose Animal/epidemiologia , Infecções por Salmonella/epidemiologia , Salmonella typhimurium/isolamento & purificação , Adolescente , Adulto , Análise de Variância , Ração Animal , Animais , Estudos de Casos e Controles , Criança , Pré-Escolar , Busca de Comunicante , Feminino , Humanos , Lactente , Masculino , New York/epidemiologia , Pennsylvania/epidemiologia , Infecções por Salmonella/microbiologia , Salmonelose Animal/microbiologia , Salmonella typhimurium/classificação , Inquéritos e Questionários
8.
J Gerontol Nurs ; 30(10): 34-42, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15515443

RESUMO

This study examined the effects of indoor gardening on socialization, activities of daily living (ADLs), and perceptions of loneliness in elderly nursing home residents. A total of 66 residents from two nursing homes participated in this two-phase study. In phase one, experimental group 1 participated once a week for 5 weeks in gardening activities while a control group received a 20-minute visit. While no significant differences were found between groups in socialization or perceptions of loneliness, there were significant pretest-posttest differences within groups on loneliness and guidance, reassurance of worth, social integration, and reliable alliance. The results also demonstrated gardening interventions had a significant effect on three ADLs (transfer, eating, and toileting). Phase two examined differences in the effects of a 5-week versus a 2-week intervention program. Although no significant within-group differences were noted in socialization, loneliness, or ADLs, the 5-week program was more effective in increasing socialization and physical functioning.


Assuntos
Atividades Cotidianas , Idoso/psicologia , Agricultura , Enfermagem Geriátrica/métodos , Promoção da Saúde/métodos , Solidão/psicologia , Socialização , Idoso de 80 Anos ou mais , Análise de Variância , Feminino , Avaliação Geriátrica , Enfermagem Geriátrica/normas , Promoção da Saúde/normas , Instituição de Longa Permanência para Idosos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Enfermagem , Avaliação em Enfermagem , Pesquisa em Avaliação de Enfermagem , Casas de Saúde , Qualidade de Vida , Fatores de Tempo
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