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1.
Ann Neurol ; 93(5): 1012-1022, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36695634

RESUMO

OBJECTIVE: Identification of genetic risk factors for Parkinson disease (PD) has to date been primarily limited to the study of single nucleotide variants, which only represent a small fraction of the genetic variation in the human genome. Consequently, causal variants for most PD risk are not known. Here we focused on structural variants (SVs), which represent a major source of genetic variation in the human genome. We aimed to discover SVs associated with PD risk by performing the first large-scale characterization of SVs in PD. METHODS: We leveraged a recently developed computational pipeline to detect and genotype SVs from 7,772 Illumina short-read whole genome sequencing samples. Using this set of SV variants, we performed a genome-wide association study using 2,585 cases and 2,779 controls and identified SVs associated with PD risk. Furthermore, to validate the presence of these variants, we generated a subset of matched whole-genome long-read sequencing data. RESULTS: We genotyped and tested 3,154 common SVs, representing over 412 million nucleotides of previously uncatalogued genetic variation. Using long-read sequencing data, we validated the presence of three novel deletion SVs that are associated with risk of PD from our initial association analysis, including a 2 kb intronic deletion within the gene LRRN4. INTERPRETATION: We identified three SVs associated with genetic risk of PD. This study represents the most comprehensive assessment of the contribution of SVs to the genetic risk of PD to date. ANN NEUROL 2023;93:1012-1022.


Assuntos
Estudo de Associação Genômica Ampla , Doença de Parkinson , Humanos , Doença de Parkinson/genética , Genoma Humano , Sequenciamento Completo do Genoma , Genótipo
2.
Haematologica ; 2024 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-38511268

RESUMO

Multiple Myeloma (MM) is an incurable plasma cell malignancy, that despite an unprecedented increase in overall survival, lacks truly risk-adapted or targeted treatments. A proportion of patients with MM depend on BCL-2 for survival and recently the BCL-2 antagonist venetoclax has shown clinical efficacy and safety in t(11;14) and BCL-2 overexpressing MM. However, only a small proportion of MM patients rely on BCL-2 (~20%), there is a need to broaden the patient population outside of t(11;14) that can be treated with venetoclax. Therefore, we took an unbiased screening approach and screened epigenetic modifiers to enhance venetoclax sensitivity in two non-BCL-2 dependent MM cell lines. The demethylase inhibitor 5-azacytidine was one of the lead hits from the screen, and the enhanced cell killing of the combination was confirmed in additional MM cell lines. Using dynamic BH3 profiling and immunoprecipitations we identified the potential mechanism of synergy is due to increased NOXA expression, through the integrated stress response. Knockdown of PMAIP1 or PKR partially rescues cell death of the venetoclax and 5-azacytidine combination treatment. The addition of a steroid to the combination treatment did not enhance the cell death and interestingly we found enhanced death of the immune cells with steroid addition, suggesting that a steroid-sparing regimen may be more beneficial in MM. Lastly, we show for the first time in primary MM patient samples, that 5-azacytidine enhances the response to venetoclax ex-vivo, across diverse anti-apoptotic dependencies (BCL-2 or MCL-1) and diverse cytogenetic backgrounds. Overall, our data identifies 5-azacytidine and venetoclax as an effective treatment combination and this could be a tolerable steroid-sparing regimen, particularly for elderly MM patients.

3.
Nature ; 561(7722): 189-194, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30209367

RESUMO

Multidrug-resistant bacteria are spreading at alarming rates, and despite extensive efforts no new class of antibiotic with activity against Gram-negative bacteria has been approved in over fifty years. Natural products and their derivatives have a key role in combating Gram-negative pathogens. Here we report chemical optimization of the arylomycins-a class of natural products with weak activity and limited spectrum-to obtain G0775, a molecule with potent, broad-spectrum activity against Gram-negative bacteria. G0775 inhibits the essential bacterial type I signal peptidase, a new antibiotic target, through an unprecedented molecular mechanism. It circumvents existing antibiotic resistance mechanisms and retains activity against contemporary multidrug-resistant Gram-negative clinical isolates in vitro and in several in vivo infection models. These findings demonstrate that optimized arylomycin analogues such as G0775 could translate into new therapies to address the growing threat of multidrug-resistant Gram-negative infections.


Assuntos
Antibacterianos/classificação , Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Peptídeos Cíclicos/farmacologia , Biocatálise/efeitos dos fármacos , Produtos Biológicos/classificação , Produtos Biológicos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Escherichia coli/enzimologia , Bactérias Gram-Negativas/enzimologia , Bactérias Gram-Negativas/patogenicidade , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/patogenicidade , Lisina/metabolismo , Proteínas de Membrana/antagonistas & inibidores , Testes de Sensibilidade Microbiana , Peptídeos Cíclicos/química , Porinas , Ligação Proteica , Domínios Proteicos , Serina Endopeptidases , Especificidade por Substrato
4.
Nature ; 557(7704): 196-201, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29720648

RESUMO

The movement of core-lipopolysaccharide across the inner membrane of Gram-negative bacteria is catalysed by an essential ATP-binding cassette transporter, MsbA. Recent structures of MsbA and related transporters have provided insights into the molecular basis of active lipid transport; however, structural information about their pharmacological modulation remains limited. Here we report the 2.9 Å resolution structure of MsbA in complex with G907, a selective small-molecule antagonist with bactericidal activity, revealing an unprecedented mechanism of ABC transporter inhibition. G907 traps MsbA in an inward-facing, lipopolysaccharide-bound conformation by wedging into an architecturally conserved transmembrane pocket. A second allosteric mechanism of antagonism occurs through structural and functional uncoupling of the nucleotide-binding domains. This study establishes a framework for the selective modulation of ABC transporters and provides rational avenues for the design of new antibiotics and other therapeutics targeting this protein family.


Assuntos
Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/química , Antibacterianos/química , Antibacterianos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/química , Quinolinas/química , Quinolinas/farmacologia , Transportadores de Cassetes de Ligação de ATP/metabolismo , Regulação Alostérica/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Sítios de Ligação/efeitos dos fármacos , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Escherichia coli/química , Hidrocarbonetos/química , Hidrocarbonetos/metabolismo , Lipopolissacarídeos/química , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Modelos Moleculares , Domínios Proteicos/efeitos dos fármacos
5.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34234017

RESUMO

Heterogeneous selection is often proposed as a key mechanism maintaining repeatable behavioral variation ("animal personality") in wild populations. Previous studies largely focused on temporal variation in selection within single populations. The relative importance of spatial versus temporal variation remains unexplored, despite these processes having distinct effects on local adaptation. Using data from >3,500 great tits (Parus major) and 35 nest box plots situated within five West-European populations monitored over 4 to 18 y, we show that selection on exploration behavior varies primarily spatially, across populations, and study plots within populations. Exploration was, simultaneously, selectively neutral in the average population and year. These findings imply that spatial variation in selection may represent a primary mechanism maintaining animal personalities, likely promoting the evolution of local adaptation, phenotype-dependent dispersal, and nonrandom settlement. Selection also varied within populations among years, which may counteract local adaptation. Our study underlines the importance of combining multiple spatiotemporal scales in the study of behavioral adaptation.


Assuntos
Migração Animal/fisiologia , Comportamento Exploratório/fisiologia , Passeriformes/fisiologia , Animais , Europa (Continente) , Dinâmica não Linear
6.
J Environ Manage ; 358: 120804, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38593736

RESUMO

Forests boast essential resources and potential to mitigate climate change, meriting the development of conservation policies on all governmental scales. Ecosystem services provided by forests, including biodiversity, air quality, and food and fuel production, make forests valuable assets for climate-vulnerable communities that often lack the means to cope with ecosystem service degradation resulting from climate change. Historically, these vulnerable communities are previously marginalized and socio-economically limited, and climate change augments already-existing injustices. Policy discussions around managing forests and carbon, therefore, must consider environmental justice as well as diversity, equity, and inclusion to better meet the needs of all constituents. Using R, we perform a review of forest, climate, and policy peer-reviewed literature published between 2018 and 2021 for prevalence of topics related to diversity, equity, inclusion, and justice (DEIJ). We select DEIJ terms a priori and a posteriori based on our understanding of DEIJ and common considerations of the literature. Out of 2891 unique articles, 15.7% of literature mentioned at least one DEIJ term in the title, keyword list, or abstract. We identify which journals have published DEIJ literature more often in the context of forest, climate, and policy, and we perform a co-occurrence analysis of additional common themes. Concepts such as ecosystem services and economics appeared often in the literature, as well as REDD+ as a specifically mentioned policy. We call for increased consideration of DEIJ in forest, climate, and policy discussions and literature, as vulnerable communities historically have been excluded from and victimized by the conversations held among large, economically motivated entities.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Justiça Ambiental , Florestas , Biodiversidade , Ecossistema , Clima , Política Ambiental
7.
Angew Chem Int Ed Engl ; 63(4): e202315297, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-37945544

RESUMO

Tailoring the hydrophobicity of supramolecular assembly building blocks enables the fabrication of well-defined functional materials. However, the selection of building blocks used in the assembly of metal-phenolic networks (MPNs), an emerging supramolecular assembly platform for particle engineering, has been essentially limited to hydrophilic molecules. Herein, we synthesized and applied biscatechol-functionalized hydrophobic polymers (poly(methyl acrylate) (PMA) and poly(butyl acrylate) (PBA)) as building blocks to engineer MPN particle systems (particles and capsules). Our method allowed control over the shell thickness (e.g., between 10 and 21 nm), stiffness (e.g., from 10 to 126 mN m-1 ), and permeability (e.g., 28-72 % capsules were permeable to 500 kDa fluorescein isothiocyanate-dextran) of the MPN capsules by selection of the hydrophobic polymer building blocks (PMA or PBA) and by controlling the polymer concentration in the MPN assembly solution (0.25-2.0 mM) without additional/engineered assembly processes. Molecular dynamics simulations provided insights into the structural states of the hydrophobic building blocks during assembly and mechanism of film formation. Furthermore, the hydrophobic MPNs facilitated the preparation of fluorescent-labeled and bioactive capsules through postfunctionalization and also particle-cell association engineering by controlling the hydrophobicity of the building blocks. Engineering MPN particle systems via building block hydrophobicity is expected to expand their use.

8.
Proc Biol Sci ; 290(2003): 20231067, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37464752

RESUMO

Cognitive flexibility controls how animals respond to changing environmental conditions. Individuals within species vary considerably in cognitive flexibility but the micro-evolutionary potential in animal populations remains enigmatic. One prerequisite for cognitive flexibility to be able to evolve is consistent and heritable among-individual variation. Here we determine the repeatability and heritability of cognitive flexibility among great tits (Parus major) by performing an artificial selection experiment on reversal learning performance using a spatial learning paradigm over three generations. We found low, yet significant, repeatability (R = 0.15) of reversal learning performance. Our artificial selection experiment showed no evidence for narrow-sense heritability of associative or reversal learning, while we confirmed the heritability of exploratory behaviour. We observed a phenotypic, but no genetic, correlation between associative and reversal learning, showing the importance of prior information on reversal learning. We found no correlation between cognitive and personality traits. Our findings emphasize that cognitive flexibility is a multi-faceted trait that is affected by memory and prior experience, making it challenging to retrieve reliable values of temporal consistency and assess the contribution of additive genetic variation. Future studies need to identify what cognitive components underlie variation in reversal learning and study their between-individual and additive genetic components.


Assuntos
Passeriformes , Reversão de Aprendizagem , Animais , Passeriformes/genética , Cognição
9.
Mol Ecol ; 32(12): 3322-3339, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36906957

RESUMO

The gut microbiota have important consequences for host biological processes and there is some evidence that they also affect fitness. However, the complex, interactive nature of ecological factors that influence the gut microbiota has scarcely been investigated in natural populations. We sampled the gut microbiota of wild great tits (Parus major) at different life stages allowing us to evaluate how microbiota varied with respect to a diverse range of key ecological factors of two broad types: (1) host state, namely age and sex, and the life history variables, timing of breeding, fecundity and reproductive success; and (2) the environment, including habitat type, the distance of the nest to the woodland edge, and the general nest and woodland site environments. The gut microbiota varied with life history and the environment in many ways that were largely dependent on age. Nestlings were far more sensitive to environmental variation than adults, pointing to a high degree of flexibility at an important time in development. As nestlings developed their microbiota from one to two weeks of life, they retained consistent (i.e., repeatable) among-individual differences. However these apparent individual differences were driven entirely by the effect of sharing the same nest. Our findings point to important early windows during development in which the gut microbiota are most sensitive to a variety of environmental drivers at multiple scales, and suggest reproductive timing, and hence potentially parental quality or food availability, are linked with the microbiota. Identifying and explicating the various ecological sources that shape an individual's gut bacteria is of vital importance for understanding the gut microbiota's role in animal fitness.


Assuntos
Microbioma Gastrointestinal , Microbiota , Passeriformes , Animais , Microbioma Gastrointestinal/genética , Bactérias , Fertilidade
10.
Biomacromolecules ; 24(1): 387-399, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36469858

RESUMO

Herein, we report a platform to integrate customizable quantities of catechol units into polymers by reacting caffeic acid carbonic anhydride with polymers having pendant amine groups. Brush poly(ethylene glycol)-caffeamide (PEG-CAF) copolymers based on oligo(ethylene glycol)methyl ether methacrylate (OEGMA500) were obtained with a catechol content of approximately 30, 40, and 50 mol % (vs OEGMA content). Owing to the hydrophobicity of the introduced CAF groups, the catechol copolymers exhibited cloud points in the range of 23-46 °C and were used to fabricate thermoresponsive FeIII metal-phenolic network capsules. Polymers with the highest CAF content (50 mol %) proved most effective for attenuating reactive oxygen species levels in vitro, in co-cultured fibroblasts, and breast cancer cells, even in the presence of an exogenous oxidant source. The reported approach to synthesize customizable catechol materials could be generalized to other amine-functional polymers, with potential biomedical applications such as adhesives or stimuli-responsive drug delivery systems.


Assuntos
Polietilenoglicóis , Polímeros , Polímeros/farmacologia , Compostos Férricos , Catecóis , Estresse Oxidativo
11.
Biol Lett ; 19(9): 20230287, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37670611

RESUMO

Many vertebrates show lateralized behaviour, or handedness, where an individual preferentially uses one side of the body more than the other. This is generally thought to be caused by brain lateralization and allows functional specializations such as sight, locomotion, and decision-making among other things. We deployed accelerometers on 51 northern gannets, Morus bassanus, to test for behavioural lateralization during plunge dives. When plunge diving, gannets 'roll' to one side, and standard indices indicated that 51% of individuals were left-sided, 43% right-sided, and 6% 'non-lateralized'. Lateralization indices provide no measure of error and do not account for environmental covariance, so we conducted two repeatability analyses on individuals' dive roll direction and angle. Dive side lateralization was highly repeatable among individuals over time at the population level (R = 0.878, p < 0.001). Furthermore, roll angle was also highly repeatable in individuals (R = 0.751, p < 0.001) even after controlling for lateralized state. Gannets show individual specializations in two different parts of the plunge diving process when attempting to catch prey. This is the first demonstration of lateralization during prey capture in a foraging seabird. It is also one of the few demonstrations of behavioural lateralization in a mixed model approach, providing a structure for further exploring behavioural lateralization.


Assuntos
Mergulho , Lateralidade Funcional , Humanos , Animais , Especialização , Aves , Locomoção
12.
Ann Vasc Surg ; 88: 239-248, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35817387

RESUMO

BACKGROUND: One strategy to address the impending shortage of vascular surgeons is to augment interest in the trainee pipeline. Endovascular procedures are unique to vascular surgery (VS) and endovascular simulations have proven effective at generating VS interest in the past. Like endovascular techniques, the use of ultrasound (US) testing in VS is unique among medical specialties. We hypothesized that an interactive US demonstration would increase VS interest in preclinical medical students. METHODS: We created a 5-point Likert scale survey assessing interest in VS, understanding of VS, likelihood to further investigate VS, choosing VS as a rotational elective, and pursuing VS shadowing and research opportunities. This survey was administered 1 day before and 1 day after the demonstration. Results were compared via paired t-test. A VS attending assisted by a senior registered vascular technologist covered physics, B-mode, continuous, pulsed wave, and color Doppler in an interactive, hands-on experience. Our dedicated US simulation laboratory enabled simultaneous interactive virtual broadcast and in-person learning. All first-year and second-year students at our medical school were invited via e-mail. RESULTS: Five hundred twelve students were invited, 39 attended, and 19 students who completed surveys were included. Sixty eight percent were female. Attendance at the US demonstration resulted in a significant increase in students' interest in vascular surgery (P = 0.012), understanding of vascular surgery (P < 0.001), likelihood to further investigate vascular surgery (P < 0.001), likelihood to choose a vascular surgery rotation (P < 0.001), and likelihood to pursue vascular surgery shadowing and research opportunities (P < 0.001). Although only 2 of 6 in-person attendees returned surveys, their increase in average response to all questions was higher than virtual attendees (+1.80 vs. +0.91, P = 0.043). CONCLUSIONS: Attending an interactive US demonstration significantly increased preclinical medical students' interest in understanding of VS. In-person and virtual attendance both had a positive impact. Such a demonstration may be an effective tool to recruit students. It is imperative that we continue innovating to address the future shortage of vascular surgeons.


Assuntos
Procedimentos Endovasculares , Especialidades Cirúrgicas , Estudantes de Medicina , Feminino , Humanos , Masculino , Escolha da Profissão , Resultado do Tratamento , Inquéritos e Questionários , Procedimentos Endovasculares/efeitos adversos
13.
Sensors (Basel) ; 23(23)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38067696

RESUMO

Data are needed to assess the relationships between urbanization and biodiversity to establish conservation priorities. However, many of these relationships are difficult to fully assess using traditional research methods. To address this gap and evaluate new acoustic sensors and associated data, we conducted a multimethod analysis of biodiversity in a rapidly urbanizing county: Greenville, South Carolina, USA. We conducted audio recordings at 25 points along a development gradient. At the same locations, we used refugia tubes, visual assessments, and an online database. Analysis focused on species identification of both audio and visual data at each point along the trail to determine relationships between both herpetofauna and acoustic indices (as proxies for biodiversity) and environmental gradient of land use and land cover. Our analysis suggests the use of a multitude of different sampling methods to be conducive to the completion of a more comprehensive occupancy measure. Moving forward, this research protocol can potentially be useful in the establishment of more effective wildlife occupancy indices using acoustic sensors to move toward future conservation policies and efforts concerning urbanization, forest fragmentation, and biodiversity in natural, particularly forested, ecosystems.


Assuntos
Ecossistema , Florestas , Biodiversidade , Urbanização , Bases de Dados Factuais , Conservação dos Recursos Naturais/métodos
14.
Int J Mol Sci ; 24(14)2023 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-37511018

RESUMO

Extramedullary multiple myeloma (or extramedullary disease, EMD) is an aggressive form of multiple myeloma (MM) that occurs when malignant plasma cells become independent of the bone marrow microenvironment. This may occur alongside MM diagnosis or in later stages of relapse and confers an extremely poor prognosis. In the era of novel agents and anti-myeloma therapies, the incidence of EMD is increasing, making this a more prevalent and challenging cohort of patients. Therefore, understanding the underlying mechanisms of bone marrow escape and EMD driver events is increasingly urgent. The role of genomics in MM has been studied extensively; however, much less is known about the genetic background of EMD. Recently there has been an increased focus on driver events for the establishment of distant EMD sites. Generally, high-risk cytogenetic abnormalities and gene signatures are associated with EMD, alongside mutations in RAS signalling pathways. More recently, changes in epigenetic regulation have also been documented, specifically the hypermethylation of DNA promoter regions. Therefore, the focus of this review is to summarize and discuss what is currently known about the genetic background of EMD in MM.


Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/patologia , Epigênese Genética , Recidiva Local de Neoplasia/genética , Plasmócitos/patologia , Medula Óssea/patologia , Microambiente Tumoral
15.
Int J Mol Sci ; 24(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37511314

RESUMO

The hominid-specific retrotransposon SINE-VNTR-Alu (SVA) is a composite element that has contributed to the genetic variation between individuals and influenced genomic structure and function. SVAs are involved in modulating gene expression and splicing patterns, altering mRNA levels and sequences, and have been associated with the development of disease. We evaluated the genome-wide effects of SVAs present in the reference genome on transcript sequence and expression in the CNS of individuals with and without the neurodegenerative disorder Amyotrophic Lateral Sclerosis (ALS). This study identified SVAs in the exons of 179 known transcripts, several of which were expressed in a tissue-specific manner, as well as 92 novel exonisation events occurring in the motor cortex. An analysis of 65 reference genome SVAs polymorphic for their presence/absence in the ALS consortium cohort did not identify any elements that were significantly associated with disease status, age at onset, and survival. However, there were transcripts, such as transferrin and HLA-A, that were differentially expressed between those with or without disease, and expression levels were associated with the genotype of proximal SVAs. This study demonstrates the functional consequences of several SVA elements altering mRNA splicing patterns and expression levels in tissues of the CNS.


Assuntos
Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/genética , Repetições Minissatélites , Elementos Nucleotídeos Curtos e Dispersos , Elementos Alu , RNA Mensageiro/genética
16.
Environ Manage ; 72(6): 1216-1227, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37500808

RESUMO

Ecosystem services (ESs) associated with surficial processes may change according to shifts in land use, land cover, and climate parameters. Estimating these shifts can be important for land development planning, as urbanization alters soil processes that can manifest legacy effects. We employed the InVEST suite of models for sediment retention, nutrient delivery, and carbon storage to postulate how these ESs will change in the Upstate of South Carolina under future precipitation and land use and land cover (LULC) scenarios. We used the average precipitation from 1981-2010 and WorldClim precipitation projections for 2021-2040 and 2041-2060 to embody climatic precipitation shifts. For our LULC scenarios, we used 2011 and 2016 NLCD landscapes, then projected future LULC to hypothesize four future scenarios. We found that for the ES models that included both precipitation and LULC as inputs, precipitation dictated ES delivery far more heavily than land use or land cover. LULC scenarios produced consistent changes in ES delivery for all models except sediment export. Phosphorus and sediment exports increased between 2011 and 2016 due to LULC change, while nitrogen export stayed the same and carbon storage decreased. Land development that prioritizes forest cover will cause the least change in ESs, but allowing for continued forest loss to low-density development will have the most intense implications for ESs. Prioritization of land uses that preserve ESs associated with surficial processes will be critical to the longevity of agriculture and ecosystem integrity in this rapidly developing region. Land development planners should integrate consideration of ESs associated with surficial processes into future regional planning.

17.
J Am Chem Soc ; 144(1): 503-514, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34958559

RESUMO

Dynamic nanostructured materials that can react to physical and chemical stimuli have attracted interest in the biomedical and materials science fields. Metal-phenolic networks (MPNs) represent a modular class of such materials: these networks form via coordination of phenolic molecules with metal ions and can be used for surface and particle engineering. To broaden the range of accessible MPN properties, we report the fabrication of thermoresponsive MPN capsules using FeIII ions and the thermoresponsive phenolic building block biscatechol-functionalized poly(N-isopropylacrylamide) (biscatechol-PNIPAM). The MPN capsules exhibited reversible changes in capsule size and shell thickness in response to temperature changes. The temperature-induced capsule size changes were influenced by the chain length of biscatechol-PNIPAM and catechol-to-FeIII ion molar ratio. The metal ion type also influenced the capsule size changes, allowing tuning of the MPN capsule mechanical properties. AlIII-based capsules, having a lower stiffness value (10.7 mN m-1), showed a larger temperature-induced size contraction (∼63%) than TbIII-based capsules, which exhibit a higher stiffness value (52.6 mN m-1) and minimal size reduction (<1%). The permeability of the MPN capsules was controlled by changing the temperature (25-50 °C)─a reduced permeability was obtained as the temperature was increased above the lower critical solution temperature of biscatechol-PNIPAM. This temperature-dependent permeability behavior was exploited to encapsulate and release model cargo (500 kDa fluorescein isothiocyanate-tagged dextran) from the capsules; approximately 70% was released over 90 min at 25 °C. This approach provides a synthetic strategy for developing dynamic and thermoresponsive-tunable MPN systems for potential applications in biological science and biotechnology.

18.
Anal Chem ; 94(2): 1230-1239, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34990117

RESUMO

With recent advances and success in several drugs designed to treat acute and chronic diseases, targeted covalent inhibitors show a resurgence in drug discovery. As covalent inhibition is time-dependent, the preferred quantitative potency metric of irreversible inhibitors is the second-order rate constant kinact/Ki, rather than IC50. Here, we present the development of a mass spectrometry-based platform for rapid kinetic analysis of irreversible covalent inhibitors. Using a simple liquid handling robot for automated sample preparation and a solid-phase extraction-based RapidFire-MS system for rapid MS analysis, kinetic characterization of covalent inhibitors was performed in high throughput both by intact protein analysis and targeted multiple reaction monitoring (MRM). In addition, a bimolecular reaction model was applied to extract kinact/Ki in data fitting, providing tremendous flexibility in the experimental design to characterize covalent inhibitors with various properties. Using KRASG12C inhibitors as a test case, the platform was demonstrated to be effective for studying covalent inhibitors with a wide range of kinact/Ki values from single digit to 3 × 105 M-1 s-1.


Assuntos
Descoberta de Drogas , Proteínas Proto-Oncogênicas p21(ras) , Cinética
19.
Am J Hematol ; 97(5): 562-573, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35132679

RESUMO

There are limited prospective data on lenalidomide, subcutaneous bortezomib, and dexamethasone (RsqVd) in transplant-eligible/transplant-ineligible patients with newly diagnosed multiple myeloma. Reliable biomarkers for efficacy and toxicity are required to better tailor therapy. Two parallel studies were conducted by Cancer Trials Ireland (CTI; NCT02219178) and the Dana-Farber Cancer Institute (DFCI; NCT02441686). Patients received four 21-day cycles of RsqVd and could then receive either another 4 cycles of RsqVd or undergo autologous stem cell transplant. Postinduction/posttransplant, patients received lenalidomide maintenance, with bortezomib included for high-risk patients. The primary endpoint was overall response rate (ORR) after 4 cycles of RsqVd. Eighty-eight patients were enrolled and 84 treated across the two studies; median age was 64.7 (CTI study) and 60.0 years (DFCI study), and 59% and 57% had stage II-III disease. Pooled ORR after 4 cycles in evaluable patients was 93.5%, including 48.1% complete or very good partial responses (CTI study: 91.9%, 59.5%; DFCI study: 95.0%, 37.5%), and in the all-treated population was 85.7% (44.0%). Patients received a median of 4 (CTI study) and 8 (DFCI study) RsqVd cycles; 60% and 31% of patients (CTI study) and 33% and 51% of patients (DFCI study) underwent transplant or received further RsqVd induction, respectively. The most common toxicity was peripheral neuropathy (pooled: 68%, 7% grade 3-4; CTI study: 57%, 7%; DFCI study: 79%, 7%). Proteomics analyses indicated elevated kallikrein-6 in good versus poor responders, decreased midkine in good responders, and elevated macrophage inflammatory protein 1-alpha in patients who stopped treatment from neurotoxicity, suggesting predictive biomarkers warranting further investigation.


Assuntos
Mieloma Múltiplo , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bortezomib/efeitos adversos , Dexametasona/efeitos adversos , Humanos , Quimioterapia de Indução , Lenalidomida/efeitos adversos , Pessoa de Meia-Idade , Mieloma Múltiplo/terapia , Estudos Prospectivos
20.
J Anim Ecol ; 91(2): 320-333, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34693529

RESUMO

Organisms are constantly under selection to respond effectively to diverse, sometimes rapid, changes in their environment, but not all individuals are equally plastic in their behaviour. Although cognitive processes and personality are expected to influence individual behavioural plasticity, the effects reported are highly inconsistent, which we hypothesise is because ecological context is usually not considered. We explored how one type of behavioural plasticity, foraging flexibility, was associated with inhibitory control (assayed using a detour-reaching task) and exploration behaviour in a novel environment (a trait closely linked to the fast-slow personality axis). We investigated how these effects varied across two experimentally manipulated ecological contexts-food value and predation risk. In the first phase of the experiment, we trained great tits Parus major to retrieve high value (preferred) food that was hidden in sand so that this became the familiar food source. In the second phase, we offered them the same familiar hidden food at the same time as a new alternative option that was visible on the surface, which was either high or low value, and under either high or low perceived predation risk. Foraging flexibility was defined as the proportion of choices made during 4-min trials that were for the new alternative food source. Our assays captured consistent differences among individuals in foraging flexibility. Inhibitory control was associated with foraging flexibility-birds with high inhibitory control were more flexible when the alternative food was of high value, suggesting they inhibited the urge to select the familiar food and instead selected the new food option. Exploration behaviour also predicted flexibility-fast explorers were more flexible, supporting the information-gathering hypothesis. This tendency was especially strong under high predation risk, suggesting risk aversion also influenced the observed flexibility because fast explorers are risk prone and the new unfamiliar food was perceived to be the risky option. Thus, both behaviours predicted flexibility, and these links were at least partly dependent on ecological conditions. Our results demonstrate that an executive cognitive function (inhibitory control) and a behavioural assay of a well-known personality axis are both associated with individual variation in the plasticity of a key functional behaviour. That their effects on foraging flexibility were primarily observed as interactions with food value or predation risk treatments also suggest that the population-level consequences of some behavioural mechanisms may only be revealed across key ecological conditions.


Assuntos
Passeriformes , Animais , Comportamento Exploratório , Personalidade , Fenótipo , Comportamento Predatório
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