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1.
Proc Natl Acad Sci U S A ; 117(41): 25464-25475, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-32973096

RESUMO

Proteolysis is a major posttranslational regulator of biology inside and outside of cells. Broad identification of optimal cleavage sites and natural substrates of proteases is critical for drug discovery and to understand protease biology. Here, we present a method that employs two genetically encoded substrate phage display libraries coupled with next generation sequencing (SPD-NGS) that allows up to 10,000-fold deeper sequence coverage of the typical six- to eight-residue protease cleavage sites compared to state-of-the-art synthetic peptide libraries or proteomics. We applied SPD-NGS to two classes of proteases, the intracellular caspases, and the ectodomains of the sheddases, ADAMs 10 and 17. The first library (Lib 10AA) allowed us to identify 104 to 105 unique cleavage sites over a 1,000-fold dynamic range of NGS counts and produced consensus and optimal cleavage motifs based position-specific scoring matrices. A second SPD-NGS library (Lib hP), which displayed virtually the entire human proteome tiled in contiguous 49 amino acid sequences with 25 amino acid overlaps, enabled us to identify candidate human proteome sequences. We identified up to 104 natural linear cut sites, depending on the protease, and captured most of the examples previously identified by proteomics and predicted 10- to 100-fold more. Structural bioinformatics was used to facilitate the identification of candidate natural protein substrates. SPD-NGS is rapid, reproducible, simple to perform and analyze, inexpensive, and renewable, with unprecedented depth of coverage for substrate sequences, and is an important tool for protease biologists interested in protease specificity for specific assays and inhibitors and to facilitate identification of natural protein substrates.


Assuntos
Caspase 3/metabolismo , Proteoma , Caspase 3/genética , Regulação Enzimológica da Expressão Gênica , Humanos , Biblioteca de Peptídeos , Especificidade por Substrato
2.
N Engl J Med ; 381(1): 47-54, 2019 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-31269365

RESUMO

A 37-year-old man with a history of seminoma presented with vertigo, ataxia, and diplopia. An autoantibody specific for kelch-like protein 11 (KLHL11) was identified with the use of programmable phage display. Immunoassays were used to identify KLHL11 IgG in 12 other men with similar neurologic features and testicular disease. Immunostaining of the patient's IgG on mouse brain tissue showed sparse but distinctive points of staining in multiple brain regions, with enrichment in perivascular and perimeningeal tissues. The onset of the neurologic syndrome preceded the diagnosis of seminoma in 9 of the 13 patients. An age-adjusted estimate of the prevalence of autoimmune KLHL11 encephalitis in Olmsted County, Minnesota, was 2.79 cases per 100,000 men. (Funded by the Rochester Epidemiology Project and others.).


Assuntos
Autoanticorpos/análise , Encéfalo/imunologia , Proteínas de Transporte/imunologia , Técnicas de Visualização da Superfície Celular , Encefalite/imunologia , Doença de Hashimoto/imunologia , Síndromes Paraneoplásicas do Sistema Nervoso/imunologia , Seminoma/complicações , Neoplasias Testiculares/complicações , Adulto , Idoso , Encefalite/epidemiologia , Doença de Hashimoto/epidemiologia , Humanos , Imunoensaio , Masculino , Pessoa de Meia-Idade , Minnesota/epidemiologia , Prevalência
3.
Wound Repair Regen ; 30(2): 258-267, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34985822

RESUMO

Chronic wounds are a major health problem that cause the medical infrastructure billions of dollars every year. Chronic wounds are often difficult to heal and cause significant discomfort. Although wound specialists have numerous therapeutic modalities at their disposal, tools that could three dimensional-map wound bed physiology and guide therapy do not exist. Visual cues are the current standard but are limited to surface assessment; clinicians rely on experience to predict response to therapy. Photoacoustic (PA) ultrasound (US) is a non-invasive, hybrid imaging modality that can solve these major limitations. PA relies on the contrast generated by haemoglobin in blood which allows it to map local angiogenesis, tissue perfusion and oxygen saturation-all critical parameters for wound healing. This work evaluates the use of PA-US to monitor angiogenesis and stratify patients responding versus not-responding to therapy. We imaged 19 patients with 22 wounds once a week for at least 3 weeks. Our findings suggest that PA imaging directly visualises angiogenesis. Patients responding to therapy showed clear signs of angiogenesis and an increased rate of PA increase (p = 0.002). These responders had a significant and negative correlation between PA intensity and wound size. Hypertension was correlated to impaired angiogenesis in non-responsive patients. The rate of PA increase and hence the rate of angiogenesis was able to predict healing times within 30 days from the start of monitoring (power = 88%, alpha = 0.05). This early response detection system could help inform management and treatment strategies while improving outcomes and reducing costs.


Assuntos
Neovascularização Patológica , Cicatrização , Humanos , Morfogênese , Ultrassonografia , Cicatrização/fisiologia
4.
Phys Rev Lett ; 124(7): 075903, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32142352

RESUMO

Significant thermal rectification has the potential to revolutionize approaches to controlled heat flow and enable breakthrough technologies such as phononic computing. We demonstrate a framework based on phonon population confinement and filtering that has potential to reach rectifications that are an order of magnitude larger than previous literature. With the use of a straightforward modification of the phonon gas model, we illustrate theoretical thermal rectification in a thin film of diamond (1-10 nm) graded to dimensions >1 µm of between 25% and 250%. Utilizing this mechanism for thermal rectification sets the stage for significant development in thermal devices.

5.
Soft Matter ; 16(2): 330-336, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31701098

RESUMO

Programming the local orientation of liquid crystal elastomers (LCEs) is a differentiated approach to prepare monolithic material compositions with localized deformation. Our prior efforts prepared LCEs with surface-enforced spatial variations in orientation to localize deformation when the LCEs were subjected to directional load. However, because these surface alignment methods included regions of planar orientation, the deformation of these programmed LCEs is inherently directional. The absence of macroscopic orientation in polydomain LCEs results in uniform, nonlinear deformation in all axes (omnidirectional soft elasticity). Here, we exploit the distinct mechanical response of polydomain LCEs prepared with isotropic or nematic genesis. By localizing the polydomain genesis via masked photopolymerizations conducted at different temperatures, we detail the preparation of main-chain, polydomain LCEs that are homogeneous in composition but exhibit spatially localized programmability in their mechanical response that is uniform in all directions.

6.
Langmuir ; 35(6): 2106-2114, 2019 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-30624942

RESUMO

Understanding the effects and limitations of solid/liquid interfaces on energy transport is crucial to applications ranging from nanoscale thermal engineering to chemical synthesis. Until now, the majority of experimental evidence regarding solid/liquid interactions has been limited to macroscale observations and experiments. The lack of experimental works exploring nanoscale solid/liquid interactions has been accentuated as the body of knowledge from theory and simulations at these scales has exploded in recent years. In this study, we expand on current nanoscale thermal measurement techniques in order to more fully understand solid/liquid interfacial energy transport. We use thermal ablation threshold measurements on thick Au films in various liquids as a metric to describe thermal transport at the Au/liquid interface. Furthermore, using ultrafast pump-probe experiments, we gain insight into this transport through picosecond ultrasonic coupling at solid/liquid interfaces with known macroscopic observations. We find significant variations in both the ablation threshold and the damping of the acoustic modes within the Au films depending on nanoscopic interactions at the solid/liquid interface rather than typical macroscale metrics such as acoustic mismatch, measured contact angle, and work of adhesion.

7.
Bioorg Med Chem Lett ; 29(11): 1407-1412, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30962087

RESUMO

A series of DNA gyrase inhibitors were designed based on the X-ray structure of a parent thiophene scaffold with the objective to improve biochemical and whole-cell antibacterial activity, while reducing cardiac ion channel activity. The binding mode and overall design hypothesis of one series was confirmed with a co-crystal structure with DNA gyrase. Although some analogs retained both biochemical activity and whole-cell antibacterial activity, we were unable to significantly improve the activity of the series and analogs retained activity against the cardiac ion channels, therefore we stopped optimization efforts.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , DNA Girase/metabolismo , Desenho de Fármacos , Escherichia coli/efeitos dos fármacos , Inibidores da Topoisomerase II/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Linhagem Celular , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Humanos , Camundongos , Camundongos Knockout , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/química
8.
Angew Chem Int Ed Engl ; 58(39): 13744-13748, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31219675

RESUMO

Liquid crystal elastomers (LCEs) are anisotropic polymeric materials. When subjected to an applied stress, liquid crystalline (LC) mesogens within the elastomeric polymer network (re)orient to the loading direction. The (re)orientation during deformation results in nonlinear stress-strain dependence (referred to as soft elasticity). Here, we uniquely explore mechanotropic phase transitions in elastomers with appreciable mesogenic content and compare these responses to LCEs in the polydomain orientation. The isotropic (amorphous) elastomers undergo significant directional orientation upon loading, evident in strong birefringence and x-ray diffraction. Functionally, the mechanotropic displacement of the elastomers to load is also nonlinear. However, unlike the analogous polydomain LCE compositions examined here, the isotropic elastomers rapidly recover after deformation. The mechanotropic orientation of the mesogens in these materials increase the toughness of these thiol-ene photopolymers by nearly 1300 % relative to a chemically similar elastomer prepared from wholly isotropic precursors.

9.
Bioorg Med Chem Lett ; 28(23-24): 3793-3797, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30327146

RESUMO

Neuronal voltage-gated potassium channels, KV7s, are the molecular mediators of the M current and regulate membrane excitability in the central and peripheral neuronal systems. Herein, we report novel small molecule KV7 openers that demonstrate anti-seizure activities in electroshock and pentylenetetrazol-induced seizure models without influencing Rotarod readouts in mice. The anti-seizure activity was determined to be proportional to the unbound concentration in the brain. KV7 channels are also expressed in the bladder smooth muscle (detrusor) and activation of these channels may cause localized undesired effects. Therefore, the impact of individual KV7 isoforms was investigated in human detrusor tissue using a panel of KV7 openers with distinct activity profiles among KV7 isoforms. KCNQ4 and KCNQ5 mRNA were highly expressed in detrusor tissue, yet a compound that has significantly reduced activity on homomeric KV7.4 did not reduce detrusor contraction. This may suggest that the homomeric KV7.4 channel plays a less significant role in bladder contraction and further investigation is needed.


Assuntos
Anticonvulsivantes/química , Anticonvulsivantes/farmacologia , Epilepsia/tratamento farmacológico , Canais de Potássio KCNQ/metabolismo , Convulsões/tratamento farmacológico , Animais , Anticonvulsivantes/uso terapêutico , Epilepsia/metabolismo , Humanos , Camundongos , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Isoformas de Proteínas/metabolismo , Convulsões/metabolismo , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/metabolismo
10.
Phys Rev Lett ; 128(12): 129602, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35394300
11.
PLoS Biol ; 12(1): e1001760, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24453938

RESUMO

Over the last decade macroeconomic studies have established a clear link between student achievement on science and math tests and per capita gross domestic product (GDP) growth, supporting the widely held belief that science, technology, engineering, and math(STEM) education are important factors in the production of economic prosperity. We critique studies that use science and math tests to predict GDP growth, arguing that estimates of the future economic value of STEM education involve substantial speculation because they ignore the impacts of economic growth on biodiversity and ecosystem functionality, which, in the long-term, limit the potential for future economic growth. Furthermore, we argue that such ecological impacts can be enabled by STEM education. Therefore, we contend that the real economic imperative for the STEM pipeline is not just raising standardized test scores, but also empowering students to assess, preserve, and restore ecosystems in order to reduce ecological degradation and increase economic welfare.


Assuntos
Ecologia/educação , Instituições Acadêmicas/economia , Estudantes/psicologia , Biodiversidade , Ecologia/ética , Escolaridade , Produto Interno Bruto/tendências , Humanos , Estados Unidos
12.
Nat Mater ; 14(4): 414-20, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25686264

RESUMO

The interest in plasmonic technologies surrounds many emergent optoelectronic applications, such as plasmon lasers, transistors, sensors and information storage. Although plasmonic materials for ultraviolet-visible and near-infrared wavelengths have been found, the mid-infrared range remains a challenge to address: few known systems can achieve subwavelength optical confinement with low loss in this range. With a combination of experiments and ab initio modelling, here we demonstrate an extreme peak of electron mobility in Dy-doped CdO that is achieved through accurate 'defect equilibrium engineering'. In so doing, we create a tunable plasmon host that satisfies the criteria for mid-infrared spectrum plasmonics, and overcomes the losses seen in conventional plasmonic materials. In particular, extrinsic doping pins the CdO Fermi level above the conduction band minimum and it increases the formation energy of native oxygen vacancies, thus reducing their populations by several orders of magnitude. The substitutional lattice strain induced by Dy doping is sufficiently small, allowing mobility values around 500 cm(2) V(-1) s(-1) for carrier densities above 10(20) cm(-3). Our work shows that CdO:Dy is a model system for intrinsic and extrinsic manipulation of defects affecting electrical, optical and thermal properties, that oxide conductors are ideal candidates for plasmonic devices and that the defect engineering approach for property optimization is generally applicable to other conducting metal oxides.

13.
Ann Neurol ; 78(5): 722-30, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26290222

RESUMO

OBJECTIVE: Identification of a particular cause of meningoencephalitis can be challenging owing to the myriad bacteria, viruses, fungi, and parasites that can produce overlapping clinical phenotypes, frequently delaying diagnosis and therapy. Metagenomic deep sequencing (MDS) approaches to infectious disease diagnostics are known for their ability to identify unusual or novel viruses and thus are well suited for investigating possible etiologies of meningoencephalitis. METHODS: We present the case of a 74-year-old woman with endophthalmitis followed by meningoencephalitis. MDS of her cerebrospinal fluid (CSF) was performed to identify an infectious agent. RESULTS: Sequences aligning to Balamuthia mandrillaris ribosomal RNA genes were identified in the CSF by MDS. Polymerase chain reaction subsequently confirmed the presence of B. mandrillaris in CSF, brain tissue, and vitreous fluid from the patient's infected eye. B. mandrillaris serology and immunohistochemistry for free-living amoebas on the brain biopsy tissue were positive. INTERPRETATION: The diagnosis was made using MDS after the patient had been hospitalized for several weeks and subjected to costly and invasive testing. MDS is a powerful diagnostic tool with the potential for rapid and unbiased pathogen identification leading to early therapeutic targeting.


Assuntos
Amebíase/diagnóstico , Amebíase/genética , Balamuthia mandrillaris/genética , Meningoencefalite/diagnóstico , Meningoencefalite/genética , Análise de Sequência de RNA/métodos , Idoso , Amebíase/líquido cefalorraquidiano , Animais , Encéfalo/microbiologia , DNA de Protozoário/genética , Feminino , Genômica , Humanos , Meningoencefalite/líquido cefalorraquidiano , Reação em Cadeia da Polimerase , Corpo Vítreo/microbiologia
15.
Science ; 383(6685): 818-822, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38386735

RESUMO

Moving instruction "beyond Mendel" can counter inaccurate, essentialist views.


Assuntos
Genômica , Genética Humana , Racismo , Genômica/educação , Racismo/prevenção & controle , Genética Humana/educação
16.
Artigo em Inglês | MEDLINE | ID: mdl-39047150

RESUMO

Confined geometries are used to increase measurement sensitivity to thermal boundary resistance at buried SiO2 interfaces with frequency-domain thermoreflectance (FDTR). We show that radial confinement of the transducer film and additional underlying material layers prevents heat from spreading and increases the thermal penetration depth of the thermal wave. Parametric analyses are performed with finite element methods and used to examine the extent to which the thermal penetration depth increases as a function of a material's effective thermal resistance and the degree of material confinement relative to the pump beam diameter. To our surprise, results suggest that the measurement technique is not always the most sensitive to the largest thermal resistor in a multilayer material. We also find that increasing the degree to which a material is confined improves measurement sensitivity to the thermal resistance across material interfaces that are buried 10s of µm to mm below the surface. These results are used to design experimental measurements of etched, 200 nm thick SiO2 films deposited on Al2O3 substrates, and offer an opportunity for thermal scientists and engineers to characterize the thermal resistance across a broader range of material interfaces within electronic device architectures that have historically been difficult to access via experiment.

17.
Science ; 383(6685): 822-825, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38386730

RESUMO

Several widely used high school biology texts depart from established science.


Assuntos
Biologia , Sexo , Estereotipagem , Humanos , Biologia/educação , Estados Unidos , Sexismo
18.
J Econ Entomol ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39001690

RESUMO

The clover seed weevil, Tychius picirostris Fabricius (Coleoptera: Curculionidae), is a major pest in Oregon white clover seed crops. Reliance on synthetic pyrethroid insecticides and limited availability of diverse modes of action (MoAs) has increased insecticide resistance selection in regional T. picirostris populations, emphasizing the need to evaluate novel chemistries and rotational strategies for effective insecticide resistance management (IRM). The efficacy of 8 foliar insecticide formulations for managing T. picirostris adult and larval life stages was determined in small and large-plot field trials across 2 crop years. In both years, bifenthrin (Brigade 2EC), the grower's standard, showed negligible adult and larval suppression. Insecticide formulations with isocycloseram and cyantraniliprole active ingredients reduced adult and larval populations when applied at BBCH 59-60 (prebloom) and BBCH 65-66 (full bloom) growth stages, respectively. While differences in T. picirostris abundance were observed among insecticide treatments, seed yield differences were not detected in large-plot trials. Larval abundance was correlated with reduced seed yield, and an economic threshold of ≥3 larvae per 30 inflorescences was determined as a conservative larval threshold to justify foliar applications of diamide insecticides. Additional commercial white clover seed fields were surveyed to compare larval scouting techniques, including a standard Berlese funnel and a grower's do-it-yourself funnel. Both larval extraction techniques were correlated and provided similar estimates of larval abundance. These findings demonstrate new MoAs, optimal insecticide application timing, and larval monitoring methods that can be incorporated into an effective T. picirostris IRM program in white clover seed crops.

19.
J Clin Invest ; 134(13)2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38753445

RESUMO

Given the global surge in autoimmune diseases, it is critical to evaluate emerging therapeutic interventions. Despite numerous new targeted immunomodulatory therapies, comprehensive approaches to apply and evaluate the effects of these treatments longitudinally are lacking. Here, we leveraged advances in programmable-phage immunoprecipitation methodology to explore the modulation, or lack thereof, of autoantibody profiles, proteome-wide, in both health and disease. Using a custom set of over 730,000 human-derived peptides, we demonstrated that each individual, regardless of disease state, possesses a distinct and complex constellation of autoreactive antibodies. For each individual, the set of resulting autoreactivites constituted a unique immunological fingerprint, or "autoreactome," that was remarkably stable over years. Using the autoreactome as a primary output, we evaluated the relative effectiveness of various immunomodulatory therapies in altering autoantibody repertoires. We found that therapies targeting B cell maturation antigen (BCMA) profoundly altered an individual's autoreactome, while anti-CD19 and anti-CD20 therapies had minimal effects. These data both confirm that the autoreactome comprises autoantibodies secreted by plasma cells and strongly suggest that BCMA or other plasma cell-targeting therapies may be highly effective in treating currently refractory autoantibody-mediated diseases.


Assuntos
Autoanticorpos , Autoimunidade , Proteoma , Humanos , Autoanticorpos/imunologia , Feminino , Doenças Autoimunes/imunologia , Doenças Autoimunes/terapia , Masculino , Imunoterapia Adotiva/métodos , Antígeno de Maturação de Linfócitos B/imunologia , Antígeno de Maturação de Linfócitos B/metabolismo , Adulto , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/metabolismo , Antígenos CD19/imunologia , Pessoa de Meia-Idade
20.
Percept Mot Skills ; 130(1): 27-53, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36314278

RESUMO

In prior research, Irish youth displayed poor motor competence across fundamental movement skills (FMS) and functional movements (FM). Our purpose in this study was to compare FMS and FM across male and female Irish adolescents and to determine whether there are associations between these movement domains. We collected data on 373 adolescents (178 females; M age = 14.38, SD = 0.87 years) from six Irish secondary schools, including motor competence testing of 10 FMS, and 7 FM. Overall levels of motor competence of both FMS and FM were low, and certain levels of dysfunctional movement were high. We observed significant sex-based differences in both FMS and FM, and there was a moderate association between FMS and FM that warrants further investigation. There is a need for societal intervention and policy changes to address low levels of motor competence among adolescent youth.


Assuntos
Destreza Motora , Caracteres Sexuais , Humanos , Masculino , Adolescente , Feminino , Movimento , Instituições Acadêmicas
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