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1.
Commun Eng ; 3(1): 119, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39191889

RESUMO

Mosquitoes and other biting arthropods transmit diseases worldwide, causing over 700,000 deaths each year, and costing about 3 billion USD annually for Aedes species alone. Insect vectored diseases also pose a considerable threat to agricultural animals. While clothing could provide a simple solution to vector-borne diseases, modern textiles do not effectively block mosquito bites. Here we have designed three micro-resolution knitted structures, with five adjustable parameters that can block mosquito bites. These designs, which exhibit significant bite reduction were integrated into a computer numerical control knitting robot for mass production of bite-blocking garments with minimal human labor. We then quantified the comfort of blocking garments. Our knits enable individuals to protect themselves from insects amidst their day-to-day activities without impacting the environment.

2.
Sci Rep ; 14(1): 16970, 2024 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-39043800

RESUMO

B cells and the antibodies they produce are critical in host defense against pathogens and contribute to various immune-mediated diseases. B cells responding to activating signals in vitro release extracellular vesicles (EV) that carry surface antibodies, yet B cell production of EVs that express antibodies and their function in vivo is incompletely understood. Using transgenic mice expressing the Cre recombinase in B cells switching to IgG1 to induce expression of fusion proteins between emerald green fluorescent protein (emGFP) and the EV tetraspanin CD63 as a model, we identify emGFP expression in B cells responding to foreign antigen in vivo and characterize the emGFP+ EVs they release. Our data suggests that emGFP+ germinal center B cells undergoing immunoglobulin class switching to express IgG and their progeny memory B cells and plasma cells, also emGFP+, are sources of circulating antigen-specific IgG+ EVs. Furthermore, using a mouse model of influenza virus infection, we find that IgG+ EVs specific for the influenza hemagglutinin antigen protect against virus infection. In addition, crossing the B cell Cre driver EV reporter mice onto the Nba2 lupus-prone strain revealed increased circulating emGFP+ EVs that expressed surface IgG against nuclear antigens linked to autoimmunity. These data identify EVs loaded with antibodies as a novel route for antibody secretion in B cells that contribute to adaptive immune responses, with important implications for different functions of IgG+ EVs in infection and autoimmunity.


Assuntos
Linfócitos B , Vesículas Extracelulares , Imunoglobulina G , Camundongos Transgênicos , Animais , Vesículas Extracelulares/imunologia , Vesículas Extracelulares/metabolismo , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Camundongos , Linfócitos B/imunologia , Linfócitos B/metabolismo , Infecções por Orthomyxoviridae/imunologia , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Fluorescência Verde/genética , Antígenos/imunologia , Switching de Imunoglobulina , Camundongos Endogâmicos C57BL , Centro Germinativo/imunologia , Centro Germinativo/metabolismo
3.
J Am Chem Soc ; 146(18): 12454-12462, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38687180

RESUMO

Quantum defects in single-walled carbon nanotubes promote exciton localization, which enables potential applications in biodevices and quantum light sources. However, the effects of local electric fields on the emissive energy states of quantum defects and how they can be controlled are unexplored. Here, we investigate quantum defect sensitization by engineering an intrinsically disordered protein to undergo a phase change at a quantum defect site. We designed a supercharged single-chain antibody fragment (scFv) to enable a full ligand-induced folding transition from an intrinsically disordered state to a compact folded state in the presence of a cytokine. The supercharged scFv was conjugated to a quantum defect to induce a substantial local electric change upon ligand binding. Employing the detection of a proinflammatory biomarker, interleukin-6, as a representative model system, supercharged scFv-coupled quantum defects exhibited robust fluorescence wavelength shifts concomitant with the protein folding transition. Quantum chemical simulations suggest that the quantum defects amplify the optical response to the localization of charges produced upon the antigen-induced folding of the proteins, which is difficult to achieve in unmodified nanotubes. These findings portend new approaches to modulate quantum defect emission for biomarker sensing and protein biophysics and to engineer proteins to modulate binding signal transduction.


Assuntos
Teoria Quântica , Anticorpos de Cadeia Única/química , Nanotubos de Carbono/química , Dobramento de Proteína , Interleucina-6 , Humanos , Proteínas Intrinsicamente Desordenadas/química
4.
Cancer Res ; 83(13): 2105-2122, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37205636

RESUMO

Cancer cell dissemination to sentinel lymph nodes is associated with poor patient outcomes, particularly in breast cancer. The process by which cancer cells egress from the primary tumor upon interfacing with the lymphatic vasculature is complex and driven by dynamic interactions between cancer cells and stromal cells, including cancer-associated fibroblasts (CAF). The matricellular protein periostin can distinguish CAF subtypes in breast cancer and is associated with increased desmoplasia and disease recurrence in patients. However, as periostin is secreted, periostin-expressing CAFs are difficult to characterize in situ, limiting our understanding of their specific contribution to cancer progression. Here, we used in vivo genetic labeling and ablation to lineage trace periostin+ cells and characterize their functions during tumor growth and metastasis. Periostin-expressing CAFs were spatially found at periductal and perivascular margins, were enriched at lymphatic vessel peripheries, and were differentially activated by highly metastatic cancer cells versus poorly metastatic counterparts. Surprisingly, genetically depleting periostin+ CAFs slightly accelerated primary tumor growth but impaired intratumoral collagen organization and inhibited lymphatic, but not lung, metastases. Periostin ablation in CAFs impaired their ability to deposit aligned collagen matrices and inhibited cancer cell invasion through collagen and across lymphatic endothelial cell monolayers. Thus, highly metastatic cancer cells mobilize periostin-expressing CAFs in the primary tumor site that promote collagen remodeling and collective cell invasion within lymphatic vessels and ultimately to sentinel lymph nodes. SIGNIFICANCE: Highly metastatic breast cancer cells activate a population of periostin-expressing CAFs that remodel the extracellular matrix to promote escape of cancer cells into lymphatic vessels and drive colonization of proximal lymph nodes.


Assuntos
Neoplasias da Mama , Linfonodos , Humanos , Feminino , Linfonodos/patologia , Neoplasias da Mama/patologia , Células Estromais/patologia , Invasividade Neoplásica/patologia
5.
Sci Adv ; 9(10): eabq1990, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36897954

RESUMO

Ancestral metabolic processes involve the reversible oxidation of molecular hydrogen by hydrogenase. Extant hydrogenase enzymes are complex, comprising hundreds of amino acids and multiple cofactors. We designed a 13-amino acid nickel-binding peptide capable of robustly producing molecular hydrogen from protons under a wide variety of conditions. The peptide forms a di-nickel cluster structurally analogous to a Ni-Fe cluster in [NiFe] hydrogenase and the Ni-Ni cluster in acetyl-CoA synthase, two ancient, extant proteins central to metabolism. These experimental results demonstrate that modern enzymes, despite their enormous complexity, likely evolved from simple peptide precursors on early Earth.


Assuntos
Hidrogenase , Níquel , Níquel/química , Níquel/metabolismo , Hidrogenase/química , Prótons , Hidrogênio/química , Peptídeos
6.
Sci Adv ; 8(27): eabh3421, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35857443

RESUMO

The VX nerve agent is one of the deadliest chemical warfare agents. Specific, sensitive, real-time detection methods for this neurotoxin have not been reported. The creation of proteins that use biological recognition to fulfill these requirements using directed evolution or library screening methods has been hampered because its toxicity makes laboratory experimentation extraordinarily expensive. A pair of VX-binding proteins were designed using a supercharged scaffold that couples a large-scale phase change from unstructured to folded upon ligand binding, enabling fully internal binding sites that present the maximum surface area possible for high affinity and specificity in target recognition. Binding site residues were chosen using a new distributed evolutionary algorithm implementation in protCAD. Both designs detect VX at parts per billion concentrations with high specificity. Computational design of fully buried molecular recognition sites, in combination with supercharged phase-changing chassis proteins, enables the ready development of a new generation of small-molecule biosensors.

7.
Artigo em Inglês | MEDLINE | ID: mdl-35162344

RESUMO

Critical temporal changes such as weekly fluctuations in surveillance systems often reflect changes in laboratory testing capacity, access to testing or healthcare facilities, or testing preferences. Many studies have noted but few have described day-of-the-week (DoW) effects in SARS-CoV-2 surveillance over the major waves of the novel coronavirus 2019 pandemic (COVID-19). We examined DoW effects by non-pharmaceutical intervention phases adjusting for wave-specific signatures using the John Hopkins University's (JHU's) Center for Systems Science and Engineering (CSSE) COVID-19 data repository from 2 March 2020 through 7 November 2021 in Middlesex County, Massachusetts, USA. We cross-referenced JHU's data with Massachusetts Department of Public Health (MDPH) COVID-19 records to reconcile inconsistent reporting. We created a calendar of statewide non-pharmaceutical intervention phases and defined the critical periods and timepoints of outbreak signatures for reported tests, cases, and deaths using Kolmogorov-Zurbenko adaptive filters. We determined that daily death counts had no DoW effects; tests were twice as likely to be reported on weekdays than weekends with decreasing effect sizes across intervention phases. Cases were also twice as likely to be reported on Tuesdays-Fridays (RR = 1.90-2.69 [95%CI: 1.38-4.08]) in the most stringent phases and half as likely to be reported on Mondays and Tuesdays (RR = 0.51-0.93 [0.44, 0.97]) in less stringent phases compared to Sundays; indicating temporal changes in laboratory testing practices and use of healthcare facilities. Understanding the DoW effects in daily surveillance records is valuable to better anticipate fluctuations in SARS-CoV-2 testing and manage appropriate workflow. We encourage health authorities to establish standardized reporting protocols.


Assuntos
COVID-19 , Teste para COVID-19 , Humanos , Massachusetts/epidemiologia , Pandemias , SARS-CoV-2
8.
IEEE Trans Vis Comput Graph ; 28(9): 3180-3192, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-33539299

RESUMO

Knitting can efficiently fabricate stretchable and durable soft surfaces. These surfaces are often designed to be worn on solid objects as covers, garments, and accessories. Given a 3D model, we consider a knit for it wearable if the knit not only reproduces the shape of the 3D model but also can be put on and taken off from the model without deforming the model. This "wearability" places additional constraints on surface design and fabrication, which existing machine knitting approaches do not take into account. We introduce the first practical automatic pipeline to generate knit designs that are both wearable and machine knittable. Our pipeline handles knittability and wearability with two separate modules that run in parallel. Specifically, given a 3D object and its corresponding 3D garment surface, our approach first converts the garment surface into a topological disc by introducing a set of cuts. The resulting cut surface is then fed into a physically-based unclothing simulation module to ensure the garment's wearability over the object. The unclothing simulation determines which of the previously introduced cuts could be sewn permanently without impacting wearability. Concurrently, the cut surface is converted into an anisotropic stitch mesh. Then, our novel, stochastic, any-time flat-knitting scheduler generates fabrication instructions for an industrial knitting machine. Finally, we fabricate the garment and manually assemble it into one complete covering worn by the target object. We demonstrate our method's robustness and knitting efficiency by fabricating models with various topological and geometric complexities. Further, we show that our method can be incorporated into a knitting design tool for creating knitted garments with customized patterns.


Assuntos
Gráficos por Computador , Dispositivos Eletrônicos Vestíveis
9.
Lang Speech Hear Serv Sch ; 52(4): 978-992, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34618545

RESUMO

Purpose This case study describes the language evaluation and treatment of a 5-year-old boy, Lucas, who is Deaf, uses American Sign Language (ASL), and presented with a language disorder despite native access to ASL and no additional diagnosis that would explain the language difficulties. Method Lucas participated in an evaluation where his nonverbal IQ, fine motor, and receptive/expressive language skills were assessed. Language assessment included both formal and informal evaluation procedures. Language intervention was delivered across 7 weeks through focused stimulation. Results Evaluation findings supported diagnosis of a language disorder unexplained by other factors. Visual analysis revealed an improvement in some behaviors targeted during intervention (i.e., number of different verbs and pronouns), but not others. In addition, descriptive analysis indicated qualitative improvement in Lucas' language production. Parent satisfaction survey results showed a high level of satisfaction with therapy progress, in addition to a belief that Lucas improved in language areas targeted. Conclusions This study adds to the growing body of literature that unexplained language disorders in signed languages exist and provides preliminary evidence for positive outcomes from language intervention for a Deaf signing child. The case described can inform professionals who work with Deaf signing children (e.g., speech-language pathologists, teachers of the Deaf, and parents of Deaf children) and serve as a potential starting point in evaluation and treatment of signed language disorders. Supplemental Material https://doi.org/10.23641/asha.16725601.


Assuntos
Surdez , Transtorno Específico de Linguagem , Criança , Pré-Escolar , Surdez/terapia , Humanos , Idioma , Masculino , Pais , Língua de Sinais
10.
Clin Nutr ESPEN ; 44: 150-158, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34330460

RESUMO

BACKGROUND: Evidence suggests that changes in dietary acid load may influence body weight, body composition, and insulin sensitivity. METHODS: Participants (n = 244) were randomly assigned to an intervention (vegan) (n = 122) or control group (n = 122) for 16 weeks. Before and after the intervention period, body composition was measured by dual X-ray absorptiometry. Insulin resistance was assessed with the Homeostasis Model Assessment (HOMA-IR) index and predicted insulin sensitivity index (PREDIM). Repeated measure ANOVA was used for statistical analysis. RESULTS: Potential Renal Acid Load (PRAL) and Net Endogenous Acid Production (NEAP) decreased significantly in the vegan group with no change in the control group (treatment effect -24.7 mEq/day [95% CI -30.2 to -19.2]; p < 0.001; and -23.8 mEq/day [95% CI -29.6 to -18.0]; p < 0.001, respectively). Body weight decreased by 6.4 kg in the vegan group, compared with 0.5 kg in the control group (treatment effect -5.9 kg [95% CI -6.8 to -5.0]; Gxt, p < 0.001), largely due to a reduction in fat mass and visceral fat. HOMA-IR index decreased and PREDIM increased in the vegan group. After adjustment for energy intake, changes in PRAL and NEAP correlated positively with changes in body weight (r = +0.37; p < 0.001; and r = +0.37; p < 0.001, respectively), fat mass (r = +0.32; p < 0.001; and r = +0.32; p < 0.001, respectively), visceral fat (r = +0.19; p = 0.006; and r = +0.15; p = 0.03, respectively), and HOMA (r = +0.17; p = 0.02; and r = +0.20; p = 0.006, respectively), and negatively with changes in PREDIM (r = -0.22; p = 0.002; and r = -0.27; p < 0.001, respectively). CONCLUSION: Dietary acid load as part of a plant-based diet was associated with changes in body weight, body composition, and insulin sensitivity, independent of energy intake. Mechanistic explanations suggest that the relationship may be causal. TRIAL REGISTRATION: ClinicalTrials.gov number, NCT03698955.


Assuntos
Resistência à Insulina , Sobrepeso , Adulto , Peso Corporal , Dieta , Dieta Vegana , Humanos
11.
Genesis ; 58(7): e23369, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32543746

RESUMO

Extracellular vesicles (EVs) are abundant, lipid-enclosed vectors that contain nucleic acids and proteins, they can be secreted from donor cells and freely circulate, and they can be engulfed by recipient cells thus enabling systemic communication between heterotypic cell types. However, genetic tools for labeling, isolating, and auditing cell type-specific EVs in vivo, without prior in vitro manipulation, are lacking. We have used CRISPR-Cas9-mediated genome editing to generate mice bearing a CD63-emGFPloxP/stop/loxP knock-in cassette that enables the specific labeling of circulating CD63+ vesicles from any cell type when crossed with lineage-specific Cre recombinase driver mice. As proof-of-principle, we have crossed these mice with Cdh5-CreERT2 mice to generate CD63emGFP+ vasculature. Using these mice, we show that developing vasculature is marked with emerald GFP (emGFP) following tamoxifen administration to pregnant females. In adult mice, quiescent vasculature and angiogenic vasculature (in tumors) is also marked with emGFP. Moreover, whole plasma-purified EVs contain a subpopulation of emGFP+ vesicles that are derived from the endothelium, co-express additional EV (e.g., CD9 and CD81) and endothelial cell (e.g., CD105) markers, and they harbor specific miRNAs (e.g., miR-126, miR-30c, and miR-125b). This new mouse strain should be a useful genetic tool for generating cell type-specific, CD63+ EVs that freely circulate in serum and can subsequently be isolated and characterized using standard methodologies.


Assuntos
Vesículas Extracelulares/metabolismo , Técnicas de Introdução de Genes/métodos , Tetraspanina 30/genética , Animais , Sistemas CRISPR-Cas , Células Cultivadas , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Integrases/genética , Integrases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Tetraspanina 30/metabolismo
12.
Sci Rep ; 9(1): 16743, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727903

RESUMO

Extracellular vesicles (EVs) play important roles in tumor progression by altering immune surveillance, promoting vascular dysfunction, and priming distant sites for organotropic metastases. The miRNA expression patterns in circulating EVs are important diagnostic tools in cancer. However, multiple cell types within the tumor microenvironment (TME) including cancer cells and stromal cells (e.g. immune cells, fibroblasts, and endothelial cells, ECs) contribute to the pool of circulating EVs. Because EVs of different cellular origins have different functional properties, auditing the cargo derived from cell type-specific EVs in the TME is essential. Here, we demonstrate that a murine EC lineage-tracing model (Cdh5-CreERT2:ZSGreenl/s/l mice) can be used to isolate EC-derived extracellular vesicles (EC-EVs). We further show that purified ZSGreen+ EVs express expected EV markers, they are transferable to multiple recipient cells, and circulating EC-EVs from tumor-bearing mice harbor elevated levels of specific miRNAs (e.g. miR-30c, miR-126, miR-146a, and miR-125b) compared to non tumor-bearing counterparts. These results suggest that, in the tumor setting, ECs may systemically direct the function of heterotypic cell types either in the circulation or in different organ micro-environments via the cargo contained within their EVs.


Assuntos
Neoplasias da Mama/genética , Células Epiteliais/citologia , Vesículas Extracelulares/genética , MicroRNAs/genética , Animais , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Camundongos , Transplante de Neoplasias , Análise de Sequência de RNA , Microambiente Tumoral , Regulação para Cima
13.
J Clin Invest ; 129(4): 1654-1670, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30855280

RESUMO

In tumors, extravascular fibrin forms provisional scaffolds for endothelial cell (EC) growth and motility during angiogenesis. We report that fibrin-mediated angiogenesis was inhibited and tumor growth delayed following postnatal deletion of Tgfbr2 in the endothelium of Cdh5-CreERT2 Tgfbr2fl/fl mice (Tgfbr2iECKO mice). ECs from Tgfbr2iECKO mice failed to upregulate the fibrinolysis inhibitor plasminogen activator inhibitor 1 (Serpine1, also known as PAI-1), due in part to uncoupled TGF-ß-mediated suppression of miR-30c. Bypassing TGF-ß signaling with vascular tropic nanoparticles that deliver miR-30c antagomiRs promoted PAI-1-dependent tumor growth and increased fibrin abundance, whereas miR-30c mimics inhibited tumor growth and promoted vascular-directed fibrinolysis in vivo. Using single-cell RNA-Seq and a NanoString miRNA array, we also found that subtypes of ECs in tumors showed spectrums of Serpine1 and miR-30c expression levels, suggesting functional diversity in ECs at the level of individual cells; indeed, fresh EC isolates from lung and mammary tumor models had differential abilities to degrade fibrin and launch new vessel sprouts, a finding that was linked to their inverse expression patterns of miR-30c and Serpine1 (i.e., miR-30chi Serpine1lo ECs were poorly angiogenic and miR-30clo Serpine1hi ECs were highly angiogenic). Thus, by balancing Serpine1 expression in ECs downstream of TGF-ß, miR-30c functions as a tumor suppressor in the tumor microenvironment through its ability to promote fibrin degradation and inhibit blood vessel formation.


Assuntos
Células Endoteliais/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , MicroRNAs/metabolismo , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , RNA Neoplásico/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Células Endoteliais/patologia , Feminino , Deleção de Genes , Neoplasias Mamárias Experimentais/irrigação sanguínea , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Transgênicos , MicroRNAs/genética , Proteínas de Neoplasias/genética , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Inibidor 1 de Ativador de Plasminogênio/genética , RNA Neoplásico/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/deficiência , Receptor do Fator de Crescimento Transformador beta Tipo II/metabolismo , Fator de Crescimento Transformador beta/genética
14.
Oncogene ; 38(26): 5191-5210, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30918328

RESUMO

Angiogenesis is critical to cancer development and metastasis. However, anti-angiogenic agents have only had modest therapeutic success, partly due to an incomplete understanding of tumor endothelial cell (EC) biology. We previously reported that the microRNA (miR)-200 family inhibits metastasis through regulation of tumor angiogenesis, but the underlying molecular mechanisms are poorly characterized. Here, using integrated bioinformatics approaches, we identified the RNA-binding protein (RBP) quaking (QKI) as a leading miR-200b endothelial target with previously unappreciated roles in the tumor microenvironment in lung cancer. In lung cancer samples, both miR-200b suppression and QKI overexpression corresponded with tumor ECs relative to normal ECs, and QKI silencing phenocopied miR-200b-mediated inhibition of sprouting. Additionally, both cancer cell and endothelial QKI expression in patient samples significantly corresponded with poor survival and correlated with angiogenic indices. QKI supported EC function by stabilizing cyclin D1 (CCND1) mRNA to promote EC G1/S cell cycle transition and proliferation. Both nanoparticle-mediated RNA interference of endothelial QKI expression and palbociclib blockade of CCND1 function potently inhibited metastasis in concert with significant effects on tumor vasculature. Altogether, this work demonstrates the clinical relevance and therapeutic potential of a novel, actionable miR/RBP axis in tumor angiogenesis and metastasis.


Assuntos
Ciclo Celular/genética , Redes Reguladoras de Genes/genética , Células Endoteliais da Veia Umbilical Humana/fisiologia , Neoplasias/patologia , Neovascularização Patológica/genética , Proteínas de Ligação a RNA/fisiologia , Animais , Ciclo Celular/fisiologia , Movimento Celular/genética , Proliferação de Células/genética , Células Cultivadas , Ciclina D1/genética , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Camundongos , Camundongos Nus , Metástase Neoplásica/genética , Neoplasias/irrigação sanguínea , Neoplasias/genética , Neovascularização Patológica/patologia , Interferência de RNA/fisiologia
15.
Curr Dev Nutr ; 2(12): nzy063, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30569029

RESUMO

Although significant achievements in human health have been made globally, progress has been made possible, in part, through unconstrained use of natural resources. As the health of our planet worsens, human health is also endangered. Scholars and policymakers from diverse disciplines highlighted complex, multisectoral approaches for addressing poor dietary intake, over- and undernutrition, and chronic diseases in sub-Saharan Africa at the Agriculture, Nutrition, Health, and the Environment in Africa Conference held at Harvard University on 6-7 November 2017. A planetary health approach to addressing these challenges offers a unique opportunity to advance solutions for environmental and social factors that influence agriculture, nutrition, and overall health in the larger context of rapid population growth and transitions in food systems and livelihoods. This paper outlines 3 key avenues for universities to promote science at the intersection of public health and the environment in sub-Saharan Africa.

17.
Nat Methods ; 15(9): 669-676, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30171252

RESUMO

Single-molecule Förster resonance energy transfer (smFRET) is increasingly being used to determine distances, structures, and dynamics of biomolecules in vitro and in vivo. However, generalized protocols and FRET standards to ensure the reproducibility and accuracy of measurements of FRET efficiencies are currently lacking. Here we report the results of a comparative blind study in which 20 labs determined the FRET efficiencies (E) of several dye-labeled DNA duplexes. Using a unified, straightforward method, we obtained FRET efficiencies with s.d. between ±0.02 and ±0.05. We suggest experimental and computational procedures for converting FRET efficiencies into accurate distances, and discuss potential uncertainties in the experiment and the modeling. Our quantitative assessment of the reproducibility of intensity-based smFRET measurements and a unified correction procedure represents an important step toward the validation of distance networks, with the ultimate aim of achieving reliable structural models of biomolecular systems by smFRET-based hybrid methods.


Assuntos
Transferência Ressonante de Energia de Fluorescência/métodos , Laboratórios/normas , Reprodutibilidade dos Testes
20.
J Clin Invest ; 128(7): 2750-2753, 2018 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-29863494

RESUMO

Stromal cells within the tumor microenvironment play a supportive role in tumor growth, progression, and treatment resistance; therefore, these nonmalignant cells are potential therapeutic targets. In this issue of the JCI, Szot et al. devised a strategy to exploit the cell-surface marker TEM8 (also known as ANTXR1), which is expressed by cancer-associated stromal cells, as a zip code to deliver an antibody-drug conjugate (ADC) linked to the potent cancer-killing drug monomethyl auristatin E (MMAE). In preclinical tumor and experimental metastasis models of multiple cancer types, TEM8-ADC targeted TEM8-expressing cancer-associated stromal cells, which processed and liberated membrane-permeable MMAE and released this drug via the P-glycoprotein (P-gp) drug transporter. Released MMAE killed cancer cells through a bystander mechanism that did minimal damage to the stromal cells themselves. P-gp-expressing tumor cells displayed MMAE resistance, suggesting that P-gp expression status may identify patients who might benefit the most from TEM8-ADC. This strategy, termed DAaRTS (drug activation and release through stroma), represents an elegant example of how selective expression of a cell-surface molecule on cancer-associated stroma can be exploited to facilitate drug delivery and shrink solid tumors.


Assuntos
Antineoplásicos , Imunoconjugados , Linhagem Celular Tumoral , Humanos , Proteínas dos Microfilamentos , Proteínas de Neoplasias , Receptores de Superfície Celular , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
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