Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 455
Filtrar
1.
Sensors (Basel) ; 24(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38732996

RESUMO

X-ray nanotomography is a powerful tool for the characterization of nanoscale materials and structures, but it is difficult to implement due to the competing requirements of X-ray flux and spot size. Due to this constraint, state-of-the-art nanotomography is predominantly performed at large synchrotron facilities. We present a laboratory-scale nanotomography instrument that achieves nanoscale spatial resolution while addressing the limitations of conventional tomography tools. The instrument combines the electron beam of a scanning electron microscope (SEM) with the precise, broadband X-ray detection of a superconducting transition-edge sensor (TES) microcalorimeter. The electron beam generates a highly focused X-ray spot on a metal target held micrometers away from the sample of interest, while the TES spectrometer isolates target photons with a high signal-to-noise ratio. This combination of a focused X-ray spot, energy-resolved X-ray detection, and unique system geometry enables nanoscale, element-specific X-ray imaging in a compact footprint. The proof of concept for this approach to X-ray nanotomography is demonstrated by imaging 160 nm features in three dimensions in six layers of a Cu-SiO2 integrated circuit, and a path toward finer resolution and enhanced imaging capabilities is discussed.

2.
Proc Natl Acad Sci U S A ; 121(16): e2400077121, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38598345

RESUMO

Type 2 alveolar epithelial cells (AEC2s) are stem cells in the adult lung that contribute to lower airway repair. Agents that promote the selective expansion of these cells might stimulate regeneration of the compromised alveolar epithelium, an etiology-defining event in several pulmonary diseases. From a high-content imaging screen of the drug repurposing library ReFRAME, we identified that dipeptidyl peptidase 4 (DPP4) inhibitors, widely used type 2 diabetes medications, selectively expand AEC2s and are broadly efficacious in several mouse models of lung damage. Mechanism of action studies revealed that the protease DPP4, in addition to processing incretin hormones, degrades IGF-1 and IL-6, essential regulators of AEC2 expansion whose levels are increased in the luminal compartment of the lung in response to drug treatment. To selectively target DPP4 in the lung with sufficient drug exposure, we developed NZ-97, a locally delivered, lung persistent DPP4 inhibitor that broadly promotes efficacy in mouse lung damage models with minimal peripheral exposure and good tolerability. This work reveals DPP4 as a central regulator of AEC2 expansion and affords a promising therapeutic approach to broadly stimulate regenerative repair in pulmonary disease.


Assuntos
Células Epiteliais Alveolares , Diabetes Mellitus Tipo 2 , Animais , Camundongos , Células Epiteliais Alveolares/metabolismo , Dipeptidil Peptidase 4/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Pulmão/metabolismo , Modelos Animais de Doenças
3.
J Med Chem ; 67(4): 2369-2378, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38335279

RESUMO

There remains a need to develop novel SARS-CoV-2 therapeutic options that improve upon existing therapies by an increased robustness of response, fewer safety liabilities, and global-ready accessibility. Functionally critical viral main protease (Mpro, 3CLpro) of SARS-CoV-2 is an attractive target due to its homology within the coronaviral family, and lack thereof toward human proteases. In this disclosure, we outline the advent of a novel SARS-CoV-2 3CLpro inhibitor, CMX990, bearing an unprecedented trifluoromethoxymethyl ketone warhead. Compared with the marketed drug nirmatrelvir (combination with ritonavir = Paxlovid), CMX990 has distinctly differentiated potency (∼5× more potent in primary cells) and human in vitro clearance (>4× better microsomal clearance and >10× better hepatocyte clearance), with good in vitro-to-in vivo correlation. Based on its compelling preclinical profile and projected once or twice a day dosing supporting unboosted oral therapy in humans, CMX990 advanced to a Phase 1 clinical trial as an oral drug candidate for SARS-CoV-2.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Diferenciação Celular , Revelação , Inibidores de Proteases/farmacologia , Inibidores de Proteases/uso terapêutico , Antivirais/farmacologia
4.
Environ Entomol ; 52(5): 779-786, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37579059

RESUMO

The squash bug, Anasa tristis (De Geer) (Hemiptera: Coreidae), is a serious pest of cucurbit crops across the United States. Conventional growers commonly use broad-spectrum insecticides to manage squash bugs, however organic growers lack these effective chemical tools and must rely on alternative management strategies. Biological control of A. tristis is largely understudied, specifically the potential of natural enemy, Hadronotus pennsylvanicus (Ashmead) (Hymenoptera: Scelionidae), as an augmentative biological control agent. For this reason, we performed early-season field releases of H. pennsylvanicus on organic farms in southeastern Virginia to test if this would improve A. tristis egg parasitism. We chose organic vegetable farms growing summer squash (Cucurbita pepo L.) as release sites and nearby Virginia Tech Agricultural Research Extension Centers (AREC) as no-release sites. Parasitoids were reared in the lab and deployed as parasitized egg masses (~2-3 females wasps/plant) in June 2020 and 2021. Before parasitoid deployment, host eggs collected from release and no-release sites displayed low levels of H. pennsylvanicus parasitism in 2020 (<21%) and 2021 (<8%). In both years, the percentage of A. tristis eggs parasitized within 2 weeks post deployment was significantly greater at release sites (~60%) than at no-release sites (~14%). High rates of H. pennsylvanicus parasitism (>72%) were further observed at release sites 4, 6, 8, and 10 weeks following parasitoid deployment. Our study demonstrates that releases of lab-reared H. pennsylvanicus can increase A. tristis egg parasitism rates and subsequently decrease successful nymph hatch rates in early summer squash plantings.

5.
Proc Natl Acad Sci U S A ; 120(28): e2305085120, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37399395

RESUMO

Chronic cutaneous wounds remain a persistent unmet medical need that decreases life expectancy and quality of life. Here, we report that topical application of PY-60, a small-molecule activator of the transcriptional coactivator Yes-associated protein (YAP), promotes regenerative repair of cutaneous wounds in pig and human models. Pharmacological YAP activation enacts a reversible pro-proliferative transcriptional program in keratinocytes and dermal cells that results in accelerated re-epithelization and regranulation of the wound bed. These results demonstrate that transient topical administration of a YAP activating agent may represent a generalizable therapeutic approach to treating cutaneous wounds.


Assuntos
Qualidade de Vida , Cicatrização , Humanos , Animais , Suínos , Cicatrização/fisiologia , Pele/lesões , Queratinócitos/metabolismo , Administração Cutânea
6.
Curr Pain Headache Rep ; 27(9): 329-337, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37515744

RESUMO

PURPOSE OF REVIEW: Migraine is common and interventions to treat or manage it vary. Physical therapists possess a varied skill set that can assess and treat limitations related to migraine and its symptoms. Conservative and non-pharmacological examination and treatment techniques for migraine and headache management are reviewed in terms of efficacy and relevance in order to describe the physical therapist's abilities and clinical reasoning process when confronting a patient with migraine symptoms. RECENT FINDINGS: A thorough examination is necessary to detect red flags and will reveal a person with migraine's biopsychosocial limitations to manage their symptoms. Strength, endurance, cervical mobility, and visual deficits are common in those reporting headaches and examination techniques, along with patient-reported outcome measures, can elicit objective data for re-assessment during an episode of care. Exercise interventions, manual therapy, biofeedback techniques, and vestibular therapy have become viable and efficacious non-pharmacological interventions in recent years to assist the patient with managing and mitigating their migraine symptoms, along with mindfulness-based exercises. A case study, with individualized treatment approaches based on examination findings, current evidence, and accrued expertise, demonstrates the clinical applicability of a physical therapist's multimodal approach to treating migraine. Psychologically- informed physical therapy with mindfulness-based approaches and biofeedback can help a patient gain more control over their symptoms and their body's response to head pain, while exercise and vestibular therapy can assist the system with recovery and adaptation from deficits related to migraine symptoms. A thorough examination, with an individually- tailored rehabilitation plan incorporating movement and mindfulness-based therapies, is recommended.


Assuntos
Transtornos de Enxaqueca , Fisioterapeutas , Cefaleia do Tipo Tensional , Humanos , Transtornos de Enxaqueca/terapia , Transtornos de Enxaqueca/diagnóstico , Cefaleia/terapia , Cefaleia do Tipo Tensional/terapia , Terapia por Exercício
7.
Proc Natl Acad Sci U S A ; 120(20): e2300763120, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37155889

RESUMO

KEAP1 (Kelch-like ECH-associated protein), a cytoplasmic repressor of the oxidative stress responsive transcription factor Nuclear factor erythroid 2-related factor 2 (NRF2), senses the presence of electrophilic agents by modification of its sensor cysteine residues. In addition to xenobiotics, several reactive metabolites have been shown to covalently modify key cysteines on KEAP1, although the full repertoire of these molecules and their respective modifications remain undefined. Here, we report the discovery of sAKZ692, a small molecule identified by high-throughput screening that stimulates NRF2 transcriptional activity in cells by inhibiting the glycolytic enzyme pyruvate kinase. sAKZ692 treatment promotes the buildup of glyceraldehyde 3-phosphate, a metabolite which leads to S-lactate modification of cysteine sensor residues of KEAP1, resulting in NRF2-dependent transcription. This work identifies a posttranslational modification of cysteine derived from a reactive central carbon metabolite and helps further define the complex relationship between metabolism and the oxidative stress-sensing machinery of the cell.


Assuntos
Cisteína , Fator 2 Relacionado a NF-E2 , Proteína 1 Associada a ECH Semelhante a Kelch/química , Fator 2 Relacionado a NF-E2/metabolismo , Cisteína/metabolismo , Transdução de Sinais , Estresse Oxidativo
8.
Proc Natl Acad Sci U S A ; 120(10): e2302075120, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36857341
9.
Nat Commun ; 14(1): 1596, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36949079

RESUMO

Evaluating protein structures in living cells remains a challenge. Here, we investigate Interleukin-4 receptor alpha (IL-4Rα) into which the non-canonical amino acid bicyclo[6.1.0]nonyne-lysine (BCNK) is incorporated by genetic code expansion. Bioorthogonal click labeling is performed with tetrazine-conjugated dyes. To quantify the reaction yield in situ, we develop brightness-calibrated ratiometric imaging, a protocol where fluorescent signals in confocal multi-color images are ascribed to local concentrations. Screening receptor mutants bearing BCNK in the extracellular domain uncovered site-specific variations of both click efficiency and Interleukin-4 binding affinity, indicating subtle well-defined structural perturbations. Molecular dynamics and continuum electrostatics calculations suggest solvent polarization to determine site-specific variations of BCNK reactivity. Strikingly, signatures of differential click efficiency, measured for IL-4Rα in ligand-bound and free form, mirror sub-angstrom deformations of the protein backbone at corresponding locations. Thus, click efficiency by itself represents a remarkably informative readout linked to protein structure and dynamics in the native plasma membrane.


Assuntos
Lisina , Proteínas , Proteínas/metabolismo , Lisina/química , Aminoácidos/química , Código Genético , Corantes Fluorescentes/química
10.
Protein Sci ; 32(1): e4488, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36371621
11.
Eur J Med Chem ; 242: 114638, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36001933

RESUMO

Epithelial-mesenchymal transition (EMT) endows stem cell-like properties to cancer cells. Targeting this process represents a potential therapeutic approach to overcome cancer metastasis and chemotherapy resistance. FiVe1 was identified from an EMT-based synthetic lethality screen and was found to inhibit the stem cell-like properties and proliferation of not only cancer cells undergoing EMT, but also more broadly in mesenchymal cancers that include therapeutically intractable soft tissue sarcomas. FiVe1 functions by directly binding to the type III intermediate filament protein vimentin (VIM) in a mode that induces hyperphosphorylation of Ser56, which results in selective disruption of mitosis and induced multinucleation in transformed VIM-expressing mesenchymal cancer cell types. Cell-based potency (IC50 = 1.6 µM, HT-1080 fibrosarcoma), poor solubility (<1 µM) and low oral bioavailability limits the direct application of FiVe1 as an in vivo probe or therapeutic agent. To overcome these drawbacks, we performed structure-activity relationship (SAR) studies and synthesized a set of 35 new compounds, consisting of diverse modifications of the FiVe1 scaffold. Among these compounds, 4e showed a marked improvement in potency (IC50 = 44 nM, 35-fold improvement, HT-1080) and cell type selectivity (19-fold improvement), when compared to FiVe1. Improvements in the potency of 4e, in terms of overall cytotoxicity, directly correlate with VIM Ser56 phosphorylation status and the oral bioavailability and pharmacokinetic profiles of 4e in mouse are superior to FiVe1. Successful optimization also resulted in potent and selective derivatives 11a, 11j and 11k, which exhibited superior pharmacological profiles, in terms of metabolic stability and aqueous solubility. Collectively, these optimization efforts have resulted in the development of promising FiVe1 analogs with potential applications in the treatment of mesenchymal cancers, as well as in the study of VIM-related biology.


Assuntos
Transição Epitelial-Mesenquimal , Sarcoma , Animais , Linhagem Celular Tumoral , Camundongos , Mitose , Fosforilação , Vimentina/genética
12.
PLoS Pathog ; 18(2): e1009862, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35134095

RESUMO

There is a growing appreciation for the idea that bacterial utilization of host-derived lipids, including cholesterol, supports Mycobacterium tuberculosis (Mtb) pathogenesis. This has generated interest in identifying novel antibiotics that can disrupt cholesterol utilization by Mtb in vivo. Here we identify a novel small molecule agonist (V-59) of the Mtb adenylyl cyclase Rv1625c, which stimulates 3', 5'-cyclic adenosine monophosphate (cAMP) synthesis and inhibits cholesterol utilization by Mtb. Similarly, using a complementary genetic approach that induces bacterial cAMP synthesis independent of Rv1625c, we demonstrate that inducing cAMP synthesis is sufficient to inhibit cholesterol utilization in Mtb. Although the physiological roles of individual adenylyl cyclase enzymes in Mtb are largely unknown, here we demonstrate that the transmembrane region of Rv1625c is required during cholesterol metabolism. Finally, the pharmacokinetic properties of Rv1625c agonists have been optimized, producing an orally-available Rv1625c agonist that impairs Mtb pathogenesis in infected mice. Collectively, this work demonstrates a role for Rv1625c and cAMP signaling in controlling cholesterol metabolism in Mtb and establishes that cAMP signaling can be pharmacologically manipulated for the development of new antibiotic strategies.


Assuntos
Adenilil Ciclases/metabolismo , Colesterol/metabolismo , AMP Cíclico/metabolismo , Mycobacterium tuberculosis/genética , Animais , Proteínas de Bactérias/metabolismo , Camundongos Endogâmicos BALB C , Transdução de Sinais/fisiologia , Ativação Transcricional/fisiologia
13.
Science ; 375(6576): 30, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34990254

RESUMO

Fearless scientist and leader of Scripps Research.

14.
Trauma Surg Acute Care Open ; 6(1): e000744, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34527812

RESUMO

BACKGROUND: Reducing length of stay (LOS) is a major healthcare initiative. While LOS is closely linked to the diagnosis and procedure in elective surgery, many additional factors influence LOS on a trauma service. We hypothesized that more standardized patient management would lead to decreased LOS. METHODS: Retrospective analysis of Trauma Registry data compared LOS before (PRE) and after (POST) implementation of standardized processes on a trauma service. Patients were subdivided by age (over and under 65 years). Data were compared using unpaired t-test, χ2 test and analysis of variance tests, where appropriate. RESULTS: 1613 PRE and 1590 POST patients were compared. Although age and Injury Severity Score were similar, median LOS decreased by 1 day for the group overall (p<0.0001), and for subgroups over and under the age of 65 years (p<0.0001). Older patients were discharged home 13% more often in POST, compared with 4% more for younger patients. CONCLUSIONS: Improved standardization of processes on a trauma service reduced LOS in patients of all ages. A prospective study may identify specific factors associated with prolonged LOS, to allow further improvement. LEVEL OF EVIDENCE: III. STUDY TYPE: Therapeutic/Care management.

15.
Sci Adv ; 7(33)2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34380625

RESUMO

Despite the development of next-generation antiandrogens, metastatic castration-resistant prostate cancer (mCRPC) remains incurable. Here, we describe a unique semisynthetic bispecific antibody that uses site-specific unnatural amino acid conjugation to combine the potency of a T cell-recruiting anti-CD3 antibody with the specificity of an imaging ligand (DUPA) for prostate-specific membrane antigen. This format enabled optimization of structure and function to produce a candidate (CCW702) with specific, potent in vitro cytotoxicity and improved stability compared with a bispecific single-chain variable fragment format. In vivo, CCW702 eliminated C4-2 xenografts with as few as three weekly subcutaneous doses and prevented growth of PCSD1 patient-derived xenograft tumors in mice. In cynomolgus monkeys, CCW702 was well tolerated up to 34.1 mg/kg per dose, with near-complete subcutaneous bioavailability and a PK profile supporting testing of a weekly dosing regimen in patients. CCW702 is being evaluated in a first in-human clinical trial for men with mCRPC who had progressed on prior therapies (NCT04077021).


Assuntos
Anticorpos Biespecíficos , Neoplasias de Próstata Resistentes à Castração , Animais , Anticorpos Biespecíficos/farmacologia , Anticorpos Biespecíficos/uso terapêutico , Complexo CD3/uso terapêutico , Linhagem Celular Tumoral , Ensaios Clínicos como Assunto , Humanos , Ligantes , Masculino , Camundongos , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Linfócitos T
16.
Chemistry ; 27(50): 12835-12844, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34240752

RESUMO

Single-crystalline domains in intergrown microcrystalline material of the new compounds Ba22.5+x La55-x [Si129 N240-x Ox ]O3 :Ce3+ and Ba25.5+x La77-x [Si170 N312-x O9+x ]O4 :Ce3+ were identified by transmission electron microscopy (TEM). Precise diffraction data from these domains were collected with microfocused synchrotron radiation so that crystal structure elucidation of the complex disordered networks became possible. They are composed of two different interconnected slabs of which one is similar in both compounds, which explains their notorious intergrowth. The distribution of Ba and La is indicated by the analysis of bond-valence sums and by comparison with isostructural Sr28.5+x La75-x [Si170 N312-x O9+x ]O4 . Ce3+ doping leads to yellow luminescence. This is a showcase that highlights the discovery and accurate characterization of new compounds relevant for luminescence applications from heterogeneous microcrystalline samples by exploiting the capability of the combination of TEM and diffraction using the latest focusing techniques for synchrotron radiation.

17.
Nat Commun ; 12(1): 3309, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34083527

RESUMO

The ongoing pandemic caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), necessitates strategies to identify prophylactic and therapeutic drug candidates for rapid clinical deployment. Here, we describe a screening pipeline for the discovery of efficacious SARS-CoV-2 inhibitors. We screen a best-in-class drug repurposing library, ReFRAME, against two high-throughput, high-content imaging infection assays: one using HeLa cells expressing SARS-CoV-2 receptor ACE2 and the other using lung epithelial Calu-3 cells. From nearly 12,000 compounds, we identify 49 (in HeLa-ACE2) and 41 (in Calu-3) compounds capable of selectively inhibiting SARS-CoV-2 replication. Notably, most screen hits are cell-line specific, likely due to different virus entry mechanisms or host cell-specific sensitivities to modulators. Among these promising hits, the antivirals nelfinavir and the parent of prodrug MK-4482 possess desirable in vitro activity, pharmacokinetic and human safety profiles, and both reduce SARS-CoV-2 replication in an orthogonal human differentiated primary cell model. Furthermore, MK-4482 effectively blocks SARS-CoV-2 infection in a hamster model. Overall, we identify direct-acting antivirals as the most promising compounds for drug repurposing, additional compounds that may have value in combination therapies, and tool compounds for identification of viral host cell targets.


Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , Reposicionamento de Medicamentos/métodos , Pandemias , SARS-CoV-2 , Animais , COVID-19/prevenção & controle , COVID-19/virologia , Linhagem Celular , Citidina/administração & dosagem , Citidina/análogos & derivados , Citidina/farmacologia , Bases de Dados de Produtos Farmacêuticos , Descoberta de Drogas/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Células HeLa , Ensaios de Triagem em Larga Escala/métodos , Humanos , Hidroxilaminas/administração & dosagem , Hidroxilaminas/farmacologia , Mesocricetus , Nelfinavir/farmacologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/fisiologia , Replicação Viral/efeitos dos fármacos
18.
Proc Natl Acad Sci U S A ; 118(11)2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33836615

RESUMO

Gram-positive bacteria assemble a multilayered cell wall that provides tensile strength to the cell. The cell wall is composed of glycan strands cross-linked by nonribosomally synthesized peptide stems. Herein, we modify the peptide stems of the Gram-positive bacterium Bacillus subtilis with noncanonical electrophilic d-amino acids, which when in proximity to adjacent stem peptides form novel covalent 5,3-cross-links. Approximately 20% of canonical cell-wall cross-links can be replaced with synthetic cross-links. While a low level of synthetic cross-link formation does not affect B. subtilis growth and phenotype, at higher levels cell growth is perturbed and bacteria elongate. A comparison of the accumulation of synthetic cross-links over time in Gram-negative and Gram-positive bacteria highlights key differences between them. The ability to perturb cell-wall architecture with synthetic building blocks provides a novel approach to studying the adaptability, elasticity, and porosity of bacterial cell walls.


Assuntos
Parede Celular/química , Bacilos Gram-Positivos/química , Peptidoglicano/química , Aminoácidos/química , Aminoácidos/metabolismo , Bacillus subtilis/química , Bacillus subtilis/citologia , Bacillus subtilis/crescimento & desenvolvimento , Bacillus subtilis/metabolismo , Parede Celular/metabolismo , Bactérias Gram-Negativas/química , Bactérias Gram-Negativas/citologia , Bactérias Gram-Negativas/metabolismo , Bacilos Gram-Positivos/citologia , Bacilos Gram-Positivos/crescimento & desenvolvimento , Bacilos Gram-Positivos/metabolismo , Peptidoglicano/metabolismo , Peptidil Transferases/genética , Peptidil Transferases/metabolismo , Fenótipo
19.
J Econ Entomol ; 114(2): 839-847, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33675660

RESUMO

The ambrosia beetles Xylosandrus germanus (Blandford) and Xylosandrus crassiusculus (Motschulsky) bore into flood-stressed trees to establish colonies, but the influence of flooding duration on colonization is unknown. This relationship was examined by flooding trees for various time periods and evaluating colonization. In one experiment, X. germanus bored into 20 dogwood (Cornus florida L.) trees during a 3-d flood treatment. Ten trees dissected that season had no offspring present in tunnels; the remaining trees appeared healthy and bloomed the following spring. In another experiment, dogwood trees were flooded for 3 or 7 d and then dissected to assess colonization. The incidence of superficial (short unbranched) and healed (callus tissue in entrance) tunnels was greater in the 3-d trees, while the incidence of tunnels with X. germanus or offspring was greater in the 7-d trees. Four experiments (three in Ohio and one in Virginia) had flood treatments of 0 (nonflooded), 3, 5, 7, and 10 d. Numbers of tunnel entrances, tunnels with X. germanus, and incidence of tunnels with offspring or live foundresses tended to increase as flood duration increased on apple (Malus × domestica Borkh.), dogwood, and redbud (Cercis canadensis L.) in Ohio and redbud in Virginia. Nonflooded trees in Ohio had no boring activity, but ambrosia beetles bored into three nonflooded trees in Virginia. Indicators of unsuccessful colonization, such as superficial tunnels and healing, decreased as flood duration increased. These results suggest tree crops may recover from boring by ambrosia beetles following short-duration flood events, and not necessarily require culling.


Assuntos
Besouros , Gorgulhos , Ambrosia , Animais , Inundações , Controle de Insetos , Ohio , Árvores , Virginia
20.
Nat Chem Biol ; 17(7): 767-775, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33723431

RESUMO

The transcriptional coactivator Yes-associated protein 1 (YAP) orchestrates a proproliferative transcriptional program that controls the fate of somatic stem cells and the regenerative responses of certain tissues. As such, agents that activate YAP may hold therapeutic potential in disease states exacerbated by insufficient proliferative repair. Here we report the discovery of a small molecule, termed PY-60, which robustly activates YAP transcriptional activity in vitro and promotes YAP-dependent expansion of epidermal keratinocytes in mouse following topical drug administration. Chemical proteomics revealed the relevant target of PY-60 to be annexin A2 (ANXA2), a protein that directly associates with YAP at the cell membrane in response to increased cell density. PY-60 treatment liberates ANXA2 from the membrane, ultimately promoting a phosphatase-bound, nonphosphorylated and transcriptionally active form of YAP. This work reveals ANXA2 as a previously undescribed, druggable component of the Hippo pathway and suggests a mechanistic rationale to promote regenerative repair in disease.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Anexina A2/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Fatores de Transcrição/metabolismo , Administração Tópica , Células-Tronco Adultas/efeitos dos fármacos , Células-Tronco Adultas/metabolismo , Animais , Anexina A2/metabolismo , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Camundongos , Estrutura Molecular , Bibliotecas de Moléculas Pequenas/administração & dosagem , Bibliotecas de Moléculas Pequenas/química , Proteínas de Sinalização YAP
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...