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1.
Cell ; 172(3): 618-628.e13, 2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-29307492

RESUMO

Peptides have great potential to combat antibiotic resistance. While many platforms can screen peptides for their ability to bind to target cells, there are virtually no platforms that directly assess the functionality of peptides. This limitation is exacerbated when identifying antimicrobial peptides because the phenotype, death, selects against itself and has caused a scientific bottleneck that confines research to a few naturally occurring classes of antimicrobial peptides. We have used this seeming dissonance to develop Surface Localized Antimicrobial Display (SLAY), a platform that allows screening of unlimited numbers of peptides of any length, composition, and structure in a single tube for antimicrobial activity. Using SLAY, we screened ∼800,000 random peptide sequences for antimicrobial function and identified thousands of active sequences, dramatically increasing the number of known antimicrobial sequences. SLAY hits present with different potential mechanisms of peptide action and access to areas of antimicrobial physicochemical space beyond what nature has evolved. VIDEO ABSTRACT.


Assuntos
Antibacterianos/farmacologia , Descoberta de Drogas/métodos , Ensaios de Triagem em Larga Escala/métodos , Biblioteca de Peptídeos , Animais , Antibacterianos/química , Escherichia coli , Camundongos
2.
Nature ; 606(7913): 351-357, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35545677

RESUMO

Death is defined as the irreversible cessation of circulatory, respiratory or brain activity. Many peripheral human organs can be transplanted from deceased donors using protocols to optimize viability. However, tissues from the central nervous system rapidly lose viability after circulation ceases1,2, impeding their potential for transplantation. The time course and mechanisms causing neuronal death and the potential for revival remain poorly defined. Here, using the retina as a model of the central nervous system, we systemically examine the kinetics of death and neuronal revival. We demonstrate the swift decline of neuronal signalling and identify conditions for reviving synchronous in vivo-like trans-synaptic transmission in postmortem mouse and human retina. We measure light-evoked responses in human macular photoreceptors in eyes removed up to 5 h after death and identify modifiable factors that drive reversible and irreversible loss of light signalling after death. Finally, we quantify the rate-limiting deactivation reaction of phototransduction, a model G protein signalling cascade, in peripheral and macular human and macaque retina. Our approach will have broad applications and impact by enabling transformative studies in the human central nervous system, raising questions about the irreversibility of neuronal cell death, and providing new avenues for visual rehabilitation.


Assuntos
Transdução de Sinal Luminoso , Reabilitação Neurológica , Mudanças Depois da Morte , Retina , Animais , Autopsia , Morte Celular/efeitos da radiação , Sistema Nervoso Central/efeitos da radiação , Humanos , Transdução de Sinal Luminoso/efeitos da radiação , Macaca , Camundongos , Retina/metabolismo , Retina/efeitos da radiação , Fatores de Tempo
3.
Cell ; 149(2): 358-70, 2012 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-22500802

RESUMO

The function of the Vibrio 7(th) pandemic island-1 (VSP-1) in cholera pathogenesis has remained obscure. Utilizing chromatin immunoprecipitation sequencing and RNA sequencing to map the regulon of the master virulence regulator ToxT, we identify a TCP island-encoded small RNA that reduces the expression of a previously unrecognized VSP-1-encoded transcription factor termed VspR. VspR modulates the expression of several VSP-1 genes including one that encodes a novel class of di-nucleotide cyclase (DncV), which preferentially synthesizes a previously undescribed hybrid cyclic AMP-GMP molecule. We show that DncV is required for efficient intestinal colonization and downregulates V. cholerae chemotaxis, a phenotype previously associated with hyperinfectivity. This pathway couples the actions of previously disparate genomic islands, defines VSP-1 as a pathogenicity island in V. cholerae, and implicates its occurrence in 7(th) pandemic strains as a benefit for host adaptation through the production of a regulatory cyclic di-nucleotide.


Assuntos
AMP Cíclico/biossíntese , Nucleotídeos Cíclicos/metabolismo , Vibrio cholerae/metabolismo , Vibrio cholerae/patogenicidade , Animais , Proteínas de Bactérias , Sequência de Bases , Regulação Viral da Expressão Gênica , Ilhas Genômicas , Humanos , Intestinos/microbiologia , Redes e Vias Metabólicas , Camundongos , Dados de Sequência Molecular , Fósforo-Oxigênio Liases , RNA não Traduzido/metabolismo , RNA Viral/metabolismo , Alinhamento de Sequência , Fatores de Transcrição , Vibrio cholerae/genética , Virulência
4.
Proc Natl Acad Sci U S A ; 121(27): e2314702121, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38916997

RESUMO

Enlargement of the cerebrospinal fluid (CSF)-filled brain ventricles (cerebral ventriculomegaly), the cardinal feature of congenital hydrocephalus (CH), is increasingly recognized among patients with autism spectrum disorders (ASD). KATNAL2, a member of Katanin family microtubule-severing ATPases, is a known ASD risk gene, but its roles in human brain development remain unclear. Here, we show that nonsense truncation of Katnal2 (Katnal2Δ17) in mice results in classic ciliopathy phenotypes, including impaired spermatogenesis and cerebral ventriculomegaly. In both humans and mice, KATNAL2 is highly expressed in ciliated radial glia of the fetal ventricular-subventricular zone as well as in their postnatal ependymal and neuronal progeny. The ventriculomegaly observed in Katnal2Δ17 mice is associated with disrupted primary cilia and ependymal planar cell polarity that results in impaired cilia-generated CSF flow. Further, prefrontal pyramidal neurons in ventriculomegalic Katnal2Δ17 mice exhibit decreased excitatory drive and reduced high-frequency firing. Consistent with these findings in mice, we identified rare, damaging heterozygous germline variants in KATNAL2 in five unrelated patients with neurosurgically treated CH and comorbid ASD or other neurodevelopmental disorders. Mice engineered with the orthologous ASD-associated KATNAL2 F244L missense variant recapitulated the ventriculomegaly found in human patients. Together, these data suggest KATNAL2 pathogenic variants alter intraventricular CSF homeostasis and parenchymal neuronal connectivity by disrupting microtubule dynamics in fetal radial glia and their postnatal ependymal and neuronal descendants. The results identify a molecular mechanism underlying the development of ventriculomegaly in a genetic subset of patients with ASD and may explain persistence of neurodevelopmental phenotypes in some patients with CH despite neurosurgical CSF shunting.


Assuntos
Cílios , Hidrocefalia , Microtúbulos , Animais , Feminino , Humanos , Masculino , Camundongos , ATPases Associadas a Diversas Atividades Celulares/genética , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/patologia , Transtorno do Espectro Autista/metabolismo , Cílios/metabolismo , Cílios/patologia , Epêndima/metabolismo , Epêndima/patologia , Hidrocefalia/genética , Hidrocefalia/patologia , Hidrocefalia/metabolismo , Katanina/metabolismo , Katanina/genética , Microtúbulos/metabolismo , Neurônios/metabolismo , Células Piramidais/metabolismo , Células Piramidais/patologia
5.
Nucleic Acids Res ; 52(2): 801-815, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38000390

RESUMO

Although ubiquitylation had traditionally been considered limited to proteins, the discovery of non-proteinaceous substrates (e.g. lipopolysaccharides and adenosine diphosphate ribose (ADPr)) challenged this perspective. Our recent study showed that DTX2 E3 ligase efficiently ubiquitylates ADPr. Here, we show that the ADPr ubiquitylation activity is also present in another DELTEX family member, DTX3L, analysed both as an isolated catalytic fragment and the full-length PARP9:DTX3L complex, suggesting that it is a general feature of the DELTEX family. Since structural predictions show that DTX3L possesses single-stranded nucleic acids binding ability and given the fact that nucleic acids have recently emerged as substrates for ADP-ribosylation, we asked whether DELTEX E3s might catalyse ubiquitylation of an ADPr moiety linked to nucleic acids. Indeed, we show that DTX3L and DTX2 are capable of ubiquitylating ADP-ribosylated DNA and RNA synthesized by PARPs, including PARP14. Furthermore, we demonstrate that the Ub-ADPr-nucleic acids conjugate can be reversed by two groups of hydrolases, which remove either the whole adduct (e.g. SARS-CoV-2 Mac1 or PARP14 macrodomain 1) or just the Ub (e.g. SARS-CoV-2 PLpro). Overall, this study reveals ADPr ubiquitylation as a general function of the DELTEX family E3s and presents the evidence of reversible ubiquitylation of ADP-ribosylated nucleic acids.


Assuntos
ADP-Ribosilação , Ácidos Nucleicos , Ubiquitina-Proteína Ligases , Adenosina Difosfato Ribose/metabolismo , Ácidos Nucleicos/metabolismo , Ácido Okadáico/análogos & derivados , Proteínas/genética , Ubiquitina-Proteína Ligases/metabolismo , Humanos
6.
Proc Natl Acad Sci U S A ; 120(43): e2308741120, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37862383

RESUMO

Macromolecules bearing open-shell entities offer unique transport properties for both electronic and spintronic devices. This work demonstrates that, unlike their conjugated polymer counterparts, the charge carriers in radical polymers (i.e., macromolecules with nonconjugated backbones and with stable open-shell sites present at their pendant groups) are singlet cations, which opens significant avenues for manipulating macromolecular design for advanced solid-state transport in these highly transparent conductors. Despite this key point, magnetoresistive effects are present in radical polymer thin films under applied magnetic fields due to the presence of impurity sites in low (i.e., <1%) concentrations. Additionally, thermal annealing of poly(4-glycidyloxy-2,2,6,6- tetramethylpiperidine-1-oxyl) (PTEO), a nonconjugated polymer with stable open-shell pendant groups, facilitated better electron exchange and pairwise spin interactions resulting in an unexpected magnetoresistance signal at relatively low field strengths (i.e., <2 T). The addition of 4-hydroxy-2,2,6,6-tetramethylpiperidin-N-oxy (TEMPO-OH), a paramagnetic species, increased the magnitude of the MR effect when the small molecule was added to the radical polymer matrix. These macroscopic experimental observables are explained using computational approaches that detail the fundamental molecular principles. This intrinsic localized charge transport behavior differs from the current state of the art regarding closed-shell conjugated macromolecules, and it opens an avenue towards next-generation transport in organic electronic materials.

7.
FASEB J ; 38(5): e23518, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38441532

RESUMO

NUDC (nuclear distribution protein C) is a mitotic protein involved in nuclear migration and cytokinesis across species. Considered a cytoplasmic dynein (henceforth dynein) cofactor, NUDC was shown to associate with the dynein motor complex during neuronal migration. NUDC is also expressed in postmitotic vertebrate rod photoreceptors where its function is unknown. Here, we examined the role of NUDC in postmitotic rod photoreceptors by studying the consequences of a conditional NUDC knockout in mouse rods (rNudC-/- ). Loss of NUDC in rods led to complete photoreceptor cell death at 6 weeks of age. By 3 weeks of age, rNudC-/- function was diminished, and rhodopsin and mitochondria were mislocalized, consistent with dynein inhibition. Levels of outer segment proteins were reduced, but LIS1 (lissencephaly protein 1), a well-characterized dynein cofactor, was unaffected. Transmission electron microscopy revealed ultrastructural defects within the rods of rNudC-/- by 3 weeks of age. We investigated whether NUDC interacts with the actin modulator cofilin 1 (CFL1) and found that in rods, CFL1 is localized in close proximity to NUDC. In addition to its potential role in dynein trafficking within rods, loss of NUDC also resulted in increased levels of phosphorylated CFL1 (pCFL1), which would purportedly prevent depolymerization of actin. The absence of NUDC also induced an inflammatory response in Müller glia and microglia across the neural retina by 3 weeks of age. Taken together, our data illustrate the critical role of NUDC in actin cytoskeletal maintenance and dynein-mediated protein trafficking in a postmitotic rod photoreceptor.


Assuntos
Actinas , Dineínas , Animais , Camundongos , Transporte Biológico , Morte Celular , Dineínas/genética , Células Fotorreceptoras Retinianas Bastonetes
8.
Proc Natl Acad Sci U S A ; 119(15): e2109448119, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35394871

RESUMO

Genetic studies of hippocampal granule neuron development have been used to elucidate cellular functions of Pten and Fmr1. While mutations in each gene cause neurodevelopmental disorders such as autism and fragile X syndrome, how Pten and Fmr1 function alone or together during normal development is not known. Moreover, Pten mRNA is bound by the fragile X mental retardation protein (FMRP) RNA binding protein, but how this physical interaction impinges on phosphatase and tensin homolog protein (PTEN) expression is not known. To understand the interaction of PTEN and FMRP, we investigated the dentate gyrus granule neuron development in Pten and Fmr1 knockout (KO) mice. Interestingly, heterozygosity of Pten restored Fmr1 KO cellular phenotypes, including dendritic arborization, and spine density, while PTEN protein expression was significantly increased in Fmr1 KO animals. However, complete deletion of both Pten and Fmr1 resulted in a dramatic increase in dendritic length, spine density, and spine length. In addition, overexpression of PTEN in Fmr1 KO Pten heterozygous background reduced dendritic length, arborization, spine density, and spine length including pS6 levels. Our findings suggest that PTEN levels are negatively regulated by FMRP, and some Fmr1 KO phenotypes are caused by dysregulation of PTEN protein. These observations provide evidence for the genetic interaction of PTEN and FMRP and a possible mechanistic basis for the pathogenesis of Fmr1-related fragile X neurodevelopmental disorders.


Assuntos
Proteína do X Frágil da Deficiência Intelectual , Síndrome do Cromossomo X Frágil , PTEN Fosfo-Hidrolase , Animais , Giro Denteado/citologia , Giro Denteado/crescimento & desenvolvimento , Modelos Animais de Doenças , Proteína do X Frágil da Deficiência Intelectual/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/metabolismo , Heterozigoto , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurogênese/genética , Neurônios/metabolismo , Neurônios/patologia , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo
9.
Nano Lett ; 24(38): 11954-11959, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39269787

RESUMO

Intercalation of several elements (Ag, Bi, In, Mo, Os, Pd, Pt, Rh, Ru, Sb, and W) is used to chemically alter a wide range of properties of two-dimensional layered α-MoO3. Intercalation modifies acoustic phonons and elastic constants, as measured with Brillouin scattering. Intercalation alters electronic bandgaps, color, structure, Raman shifts, and electron binding energies. Optical chemochromism is demonstrated with intercalants changing the color of MoO3 from transparent to brilliant blue (In, Mo, Os, and Ru) and orange (Ag). Correlations are investigated among material properties. There is evidence that in-plane longitudinal stiffness c11 correlates with changes in the bandgap, while various Raman modes appear to be connected to a variety of properties, including shear modulus c55, Mo binding energies, lattice constants, and the preferred crystal structure of the intercalant. The results indicate a surprising degree of complexity, suggesting competition among multiple distinct mechanisms and interactions involving specific intercalant species.

10.
J Neurosci ; 43(5): 827-845, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36526374

RESUMO

Hyperactivation of PI3K/PTEN-mTOR signaling during neural development is associated with focal cortical dysplasia (FCD), autism, and epilepsy. mTOR can signal through two major hubs, mTORC1 and mTORC2, both of which are hyperactive following PTEN loss of function (LOF). Here, we tested the hypothesis that genetic inactivation of the mTORC2 complex via deletion of Rictor is sufficient to rescue morphologic and electrophysiological abnormalities in the dentate gyrus caused by PTEN loss, as well as generalized seizures. An established, early postnatal mouse model of PTEN loss in male and female mice showed spontaneous seizures that were not prevented by mTORC2 inactivation. This lack of rescue occurred despite the normalization or amelioration of many morphologic and electrophysiological phenotypes. However, increased excitatory connectivity proximal to dentate gyrus granule neuron somas was not normalized by mTORC2 inactivation. Further studies demonstrated that, although mTORC2 inactivation largely rescued the dendritic arbor overgrowth caused by PTEN LOF, it increased synaptic strength and caused additional impairments of presynaptic function. These results suggest that a constrained increase in excitatory connectivity and co-occurring synaptic dysfunction is sufficient to generate seizures downstream of PTEN LOF, even in the absence of characteristic changes in morphologic properties.SIGNIFICANCE STATEMENT Homozygous deletion of the Pten gene in neuronal subpopulations in the mouse serves as a valuable model of epilepsy caused by mTOR hyperactivation. To better understand the physiological mechanisms downstream of Pten loss that cause epilepsy, as well as the therapeutic potential of targeted gene therapies, we tested whether genetic inactivation of the mTORC2 complex could improve the cellular, synaptic, and in vivo effects of Pten loss in the dentate gyrus. We found that mTORC2 inhibition improved or rescued all morphologic effects of Pten loss in the dentate gyrus, but synaptic changes and seizures persisted. These data suggest that synaptic dysfunction can drive epilepsy caused by hyperactivation of PI3K/PTEN-mTOR, and that future therapies should focus on this mechanistic link.


Assuntos
Epilepsia , Convulsões , Masculino , Feminino , Camundongos , Animais , Alvo Mecanístico do Complexo 2 de Rapamicina/genética , Homozigoto , Camundongos Knockout , Deleção de Sequência , Serina-Treonina Quinases TOR/genética , Epilepsia/genética , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases
11.
Anal Chem ; 96(28): 11255-11262, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38967238

RESUMO

Molten salts have a significant potential for use as next-generation nuclear reactor coolants and in pyroprocessing for the recycling of used nuclear fuel. However, the molten salt composition needs to be known at all times, and high temperatures and intense ionizing radiation pose challenges for the monitoring instrumentation. Although the technique of laser-induced breakdown spectroscopy (LIBS) has been studied for in situ measurements of molten salts, trials to improve its monitoring accuracy using chemometrics are lacking. In this study, a data fusion technique using the LIBS optical and laser-induced acoustic (LIA) signals was investigated to enhance the measurement accuracy for molten salt monitoring. Prediction models were constructed using the partial least-squares method, and the variable importance in projection scores was analyzed to evaluate the effect of incorporating the LIA signal into the analysis. This study investigates rare earth elements Eu, Er, and Pr found not only in nuclear but also in other settings such as laser and magnetic materials. The analysis of LIBS data without data fusion resulted in a root-mean-square error of prediction (RMSEP) of 0.0774-0.0913 wt %, whereas the prediction model using data fusion led to approximately 18-40% enhanced RMSEP (0.0461-0.0679 wt %). The results suggest that fusing the LIBS data with the simultaneously recorded LIA data can improve the monitoring accuracy of rare earth element composition in molten salts.

12.
J Urol ; : 101097JU0000000000004186, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39146526

RESUMO

PURPOSE: Ultrasonic propulsion is an investigational procedure for awake patients. Our purpose was to evaluate whether ultrasonic propulsion to facilitate residual kidney stone fragment clearance reduced relapse. MATERIALS AND METHODS: This multicenter, prospective, open-label, randomized, controlled trial used single block randomization (1:1) without masking. Adults with residual fragments (individually ≤5 mm) were enrolled. Primary outcome was relapse as measured by stone growth, a stone-related urgent medical visit, or surgery by 5 years or study end. Secondary outcomes were fragment passage within 3 weeks and adverse events within 90 days. Cumulative incidence of relapse was estimated using the Kaplan-Meier method. Log-rank test was used to compare the treatment (ultrasonic propulsion) and control (observation) groups. RESULTS: The trial was conducted from May 9, 2015, through April 6, 2024. Median follow-up (interquartile range) was 3.0 (1.8-3.2) years. The treatment group (n = 40) had longer time to relapse than the control group (n = 42; P < .003). The restricted mean time-to-relapse was 52% longer in the treatment group than in the control group (1530 ± 92 days vs 1009 ± 118 days), and the risk of relapse was lower (hazard ratio 0.30, 95% CI 0.13-0.68) with 8 of 40 and 21 of 42 participants, respectively, experiencing relapse. Omitting 3 participants not asked about passage, 24 treatment (63%) and 2 control (5%) participants passed fragments within 3 weeks of treatment. adverse events were mild, transient, and self-resolving, and were reported in 25 treated participants (63%) and 17 controls (40%). CONCLUSIONS: Ultrasonic propulsion reduced relapse and added minimal risk. CLINICAL TRIAL REGISTRATION NO.: NCT02028559.

13.
Environ Sci Technol ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39263826

RESUMO

Lithium is a critical mineral in a wide range of current technologies, and demand continues to grow with the transition to a green economy. Current lithium mining and extraction practices are often highly ecologically damaging, in part due to the large amount of water and energy they consume. Biomineralization is a natural process that transforms inorganic precursors to minerals. Microbial biomineralization has potential as an ecofriendly alternative to current lithium extraction techniques. This work demonstrates Lysinibacillus sphaericus biomineralization of lithium chloride to lithium hydroxide. Quantitative analysis of biomineralized lithium via the 2-(2-hydroxyphenyl)-benzoxazole fluorescence assay reveals significantly greater recovery with L. sphaericus than without. Furthermore, L. sphaericus biomineralization is specific to lithium over sodium. The nanoparticles produced were further characterized via Fourier transform infrared and transmission electron microscopy analysis as crystalline lithium hydroxide, which is an advanced functional material. Finally, ESI-LC/MS was used to identify several proteins involved in this microbial biomineralization process, including the S-layer protein. Through the isolation of L. sphaericus ghosts, this work shows that the S-layer protein alone plays a critical role in the biomineralization of crystalline lithium hydroxide nanoparticles. Through this study of microbial biomineralization of lithium with L. sphaericus, there is potential to develop innovative and environmentally friendly extraction techniques.

14.
Environ Sci Technol ; 58(22): 9548-9558, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38778038

RESUMO

Agricultural applications of nanotechnologies necessitate addressing safety concerns associated with nanopesticides, yet research has not adequately elucidated potential environmental risks between nanopesticides and their conventional counterparts. To address this gap, we investigated the risk of nanopesticides by comparing the ecotoxicity of nanoencapsulated imidacloprid (nano-IMI) with its active ingredient to nontarget freshwater organisms (embryonic Danio rerio, Daphnia magna, and Chironomus kiinensis). Nano-IMI elicited approximately 5 times higher toxicity than IMI to zebrafish embryos with and without chorion, while no significant difference was observed between the two invertebrates. Toxicokinetics further explained the differential toxicity patterns of the two IMI analogues. One-compartmental two-phase toxicokinetic modeling showed that nano-IMI exhibited significantly slower elimination and subsequently higher bioaccumulation potential than IMI in zebrafish embryos (dechorinated), while no disparity in toxicokinetics was observed between nano-IMI and IMI in D. magna and C. kiinensis. A two-compartmental toxicokinetic model successfully simulated the slow elimination of IMI from C. kiinensis and confirmed that both analogues of IMI reached toxicologically relevant targets at similar levels. Although nanopesticides exhibit comparable or elevated toxicity, future work is of utmost importance to properly understand the life cycle risks from production to end-of-life exposures, which helps establish optimal management measures before their widespread applications.


Assuntos
Água Doce , Toxicocinética , Peixe-Zebra , Animais , Água Doce/química , Poluentes Químicos da Água/toxicidade , Daphnia/efeitos dos fármacos , Neonicotinoides/toxicidade
15.
Environ Sci Technol ; 58(39): 17235-17246, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39287556

RESUMO

Molecular, cellular, and organismal alterations are important descriptors of toxic effects, but our ability to extrapolate and predict ecological risks is limited by the availability of studies that link measurable end points to adverse population relevant outcomes such as cohort survival and growth. In this study, we used laboratory gene expression and behavior data from two populations of Atlantic killifish Fundulus heteroclitus [one reference site (SCOKF) and one PCB-contaminated site (NBHKF)] to inform individual-based models simulating cohort growth and survival from embryonic exposures to environmentally relevant concentrations of neurotoxicants. Methylmercury exposed SCOKF exhibited brain gene expression changes in the si:ch211-186j3.6, si:dkey-21c1.4, scamp1, and klhl6 genes, which coincided with changes in feeding and swimming behaviors, but our models simulated no growth or survival effects of exposures. PCB126-exposed SCOKF had lower physical activity levels coinciding with a general upregulation in nucleic and cellular brain gene sets (BGS) and downregulation in signaling, nucleic, and cellular BGS. The NBHKF, known to be tolerant to PCBs, had altered swimming behaviors that coincided with 98% fewer altered BGS. Our models simulated PCB126 decreased growth in SCOKF and survival in SCOKF and NBHKF. Overall, our study provides a unique demonstration linking molecular and behavioral data to develop quantitative, testable predictions of ecological risk.


Assuntos
Fundulidae , Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/toxicidade , Fundulidae/genética , Bifenilos Policlorados/toxicidade , Compostos de Metilmercúrio/toxicidade , Comportamento Animal/efeitos dos fármacos , Neurotoxinas/toxicidade , Fundulus heteroclitus
16.
Environ Sci Technol ; 58(35): 15415-15427, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-38696305

RESUMO

Identifying causative toxicants in mixtures is critical, but this task is challenging when mixtures contain multiple chemical classes. Effect-based methods are used to complement chemical analyses to identify toxicants, yet conventional bioassays typically rely on an apical and/or single endpoint, providing limited diagnostic potential to guide chemical prioritization. We proposed an event-driven taxonomy framework for mixture risk assessment that relied on high-throughput screening bioassays and toxicant identification integrated by deep learning. In this work, the framework was evaluated using chemical mixtures in sediments eliciting aryl-hydrocarbon receptor activation and oxidative stress response. Mixture prediction using target analysis explained <10% of observed sediment bioactivity. To identify additional contaminants, two deep learning models were developed to predict fingerprints of a pool of bioactive substances (event driver fingerprint, EDFP) and convert these candidates to MS-readable information (event driver ion, EDION) for nontarget analysis. Two libraries with 121 and 118 fingerprints were established, and 247 bioactive compounds were identified at confidence level 2 or 3 in sediment extract using GC-qToF-MS. Among them, 12 toxicants were analytically confirmed using reference standards. Collectively, we present a "bioactivity-signature-toxicant" strategy to deconvolute mixtures and to connect patchy data sets and guide nontarget analysis for diverse chemicals that elicit the same bioactivity.


Assuntos
Aprendizado Profundo , Sedimentos Geológicos , Sedimentos Geológicos/química , Poluentes Químicos da Água/toxicidade , Cromatografia Gasosa-Espectrometria de Massas
17.
Environ Sci Technol ; 58(3): 1473-1483, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38205949

RESUMO

Though toxins produced during harmful blooms of cyanobacteria present diverse risks to public health and the environment, surface water quality surveillance of cyanobacterial toxins is inconsistent, spatiotemporally limited, and routinely relies on ELISA kits to estimate total microcystins (MCs) in surface waters. Here, we employed liquid chromatography tandem mass spectrometry to examine common cyanotoxins, including five microcystins, three anatoxins, nodularin, cylindrospermopsin, and saxitoxin in 20 subtropical reservoirs spatially distributed across a pronounced annual rainfall gradient. Probabilistic environmental hazard analyses identified whether water quality values for cyanotoxins were exceeded and if these exceedances varied spatiotemporally. MC-LR was the most common congener detected, but it was not consistently observed with other toxins, including MC-YR, which was detected at the highest concentrations during spring with many observations above the California human recreation guideline (800 ng/L). Cylindrospermopsin was also quantitated in 40% of eutrophic reservoirs; these detections did not exceed a US Environmental Protection Agency swimming/advisory level (15,000 ng/L). Our observations have implications for routine water quality monitoring practices, which traditionally use ELISA kits to estimate MC levels and often limit collection of surface samples during summer months near reservoir impoundments, and further indicate that spatiotemporal surveillance efforts are necessary to understand cyanotoxins risks when harmful cyanobacteria blooms occur throughout the year.


Assuntos
Toxinas Bacterianas , Cianobactérias , Humanos , Microcistinas/análise , Qualidade da Água , Toxinas Marinhas , Toxinas Bacterianas/análise , Água Doce/análise , Água Doce/química , Água Doce/microbiologia , Toxinas de Cianobactérias , Cianobactérias/química , Monitoramento Ambiental/métodos
18.
Bioorg Med Chem ; 100: 117618, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38309201

RESUMO

The virally encoded 3C-like protease (3CLpro) is a well-validated drug target for the inhibition of coronaviruses including Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). Most inhibitors of 3CLpro are peptidomimetic, with a γ-lactam in place of Gln at the P1 position of the pseudopeptide chain. An effort was pursued to identify a viable alternative to the γ-lactam P1 mimetic which would improve physicochemical properties while retaining affinity for the target. Discovery of a 2-tetrahydrofuran as a suitable P1 replacement that is a potent enzymatic inhibitor of 3CLpro in SARS-CoV-2 virus is described herein.


Assuntos
Antivirais , Inibidores de Protease de Coronavírus , Furanos , Antivirais/química , Antivirais/farmacologia , Lactamas , Peptídeo Hidrolases , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , SARS-CoV-2 , Furanos/química , Inibidores de Protease de Coronavírus/química
19.
Surg Endosc ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39160315

RESUMO

BACKGROUND: Historically, DeMeester score over 14.7 has been used to diagnose GERD. The 2022 American Gastroenterological Association clinical guidelines define GERD based on acid exposure time (AET) instead of DeMeester score. We aim to compare outcomes after laparoscopic Nissen fundoplication (LNF) in patients based on differing GERD diagnostic criteria. METHODS: Patients who underwent first-time LNF between 2009 and 2017 were identified. Demographics, objective GERD evaluation, and outcomes were maintained in an IRB-approved database. Disease-specific quality of life was assessed with a survey (GERD-HRQL) with higher values representing more symptomatic disease. Descriptive statistics, Fischer's exact test and logistic regression were used to analyze the data, p-value < 0.05. RESULTS: 225 patients were stratified into two groups: borderline GERD (AET 4-6%, n = 25.11%) and GERD (AET ≥ 6%, n = 200.89%). The mean age was 50.1 ± 13.4 years and 169 (75%) were female. Baseline GERD-HRQL was lower in the borderline group (24.3 vs 30.0, p = 0.031). Short-term (5 weeks [IQR 4, 8]), medium-term (14 months [IQR 7.25, 31]) and long-term (6.75 years [IQR 5.5, 8]) follow-up was performed. GERD-HRQL scores did not differ between borderline and GERD patients at short-(6.0 vs 7.1, p = 0.630), medium-(12.0 vs 12.1, p = 0.818), or long-term follow-up (10.0 vs 9.0, p = 0.757). The absolute long-term improvement in GERD-HRQL was -12.3 (p = 0.022) vs. -21.3 (p < 0.001). At long-term follow-up there was no difference in PPI use (50% vs 47%, p = 0.852), satisfaction (58% vs 76%, p = 0.187), willingness to repeat the procedure given the benefit of hindsight (75% vs 85%, p = 0.386), or need for reoperation (14% vs 13%, p = 0.910). CONCLUSION: Both patients with borderline GERD and GERD achieve GERD-HRQL improvements at 7 years following laparoscopic Nissen fundoplication and demonstrate similar long-term PPI usage and satisfaction with surgical results. Borderline GERD patients have lower GERD-HRQL at baseline, and thus have smaller improvements in their QOL scores. Anti-reflux surgery should be considered for patients with a diagnosis of borderline GERD refractory to medical therapy.

20.
J Ultrasound Med ; 43(3): 513-523, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38050780

RESUMO

OBJECTIVES: The number and distribution of lung ultrasound (LUS) imaging artifacts termed B-lines correlate with the presence of acute lung disease such as infection, acute respiratory distress syndrome (ARDS), and pulmonary edema. Detection and interpretation of B-lines require dedicated training and is machine and operator-dependent. The goal of this study was to identify radio frequency (RF) signal features associated with B-lines in a cohort of patients with cardiogenic pulmonary edema. A quantitative signal indicator could then be used in a single-element, non-imaging, wearable, automated lung ultrasound sensor (LUSS) for continuous hands-free monitoring of lung fluid. METHODS: In this prospective study a 10-zone LUS exam was performed in 16 participants, including 12 patients admitted with acute cardiogenic pulmonary edema (mean age 60 ± 12 years) and 4 healthy controls (mean age 44 ± 21). Overall,160 individual LUS video clips were recorded. The LUS exams were performed with a phased array probe driven by an open-platform ultrasound system with simultaneous RF signal collection. RF data were analyzed offline for candidate B-line indicators based on signal amplitude, temporal variability, and frequency spectrum; blinded independent review of LUS images for the presence or absence of B-lines served as ground truth. Predictive performance of the signal indicators was determined with receiving operator characteristic (ROC) analysis with k-fold cross-validation. RESULTS: Two RF signal features-temporal variability of signal amplitude at large depths and at the pleural line-were strongly associated with B-line presence. The sensitivity and specificity of a combinatorial indicator were 93.2 and 58.5%, respectively, with cross-validated area under the ROC curve (AUC) of 0.91 (95% CI = 0.80-0.94). CONCLUSION: A combinatorial signal indicator for use with single-element non-imaging LUSS was developed to facilitate continuous monitoring of lung fluid in patients with respiratory illness.


Assuntos
Edema Pulmonar , Síndrome do Desconforto Respiratório , Humanos , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Adulto , Estudos Prospectivos , Pulmão/diagnóstico por imagem , Sensibilidade e Especificidade , Ultrassonografia/métodos
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