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1.
Nature ; 626(8001): 979-983, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38232945

RESUMO

The recent inference of sulfur dioxide (SO2) in the atmosphere of the hot (approximately 1,100 K), Saturn-mass exoplanet WASP-39b from near-infrared JWST observations1-3 suggests that photochemistry is a key process in high-temperature exoplanet atmospheres4. This is because of the low (<1 ppb) abundance of SO2 under thermochemical equilibrium compared with that produced from the photochemistry of H2O and H2S (1-10 ppm)4-9. However, the SO2 inference was made from a single, small molecular feature in the transmission spectrum of WASP-39b at 4.05 µm and, therefore, the detection of other SO2 absorption bands at different wavelengths is needed to better constrain the SO2 abundance. Here we report the detection of SO2 spectral features at 7.7 and 8.5 µm in the 5-12-µm transmission spectrum of WASP-39b measured by the JWST Mid-Infrared Instrument (MIRI) Low Resolution Spectrometer (LRS)10. Our observations suggest an abundance of SO2 of 0.5-25 ppm (1σ range), consistent with previous findings4. As well as SO2, we find broad water-vapour absorption features, as well as an unexplained decrease in the transit depth at wavelengths longer than 10 µm. Fitting the spectrum with a grid of atmospheric forward models, we derive an atmospheric heavy-element content (metallicity) for WASP-39b of approximately 7.1-8.0 times solar and demonstrate that photochemistry shapes the spectra of WASP-39b across a broad wavelength range.

2.
Genes Dev ; 34(15-16): 1075-1088, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32616520

RESUMO

Nonsense-mediated decay (NMD) is a translation-dependent RNA quality control mechanism that occurs in the cytoplasm. However, it is unknown how NMD regulates the stability of RNAs translated at the endoplasmic reticulum (ER). Here, we identify a localized NMD pathway dedicated to ER-translated mRNAs. We previously identified NBAS, a component of the Syntaxin 18 complex involved in Golgi-to-ER trafficking, as a novel NMD factor. Furthermore, we show that NBAS fulfills an independent function in NMD. This ER-NMD pathway requires the interaction of NBAS with the core NMD factor UPF1, which is partially localized at the ER in the proximity of the translocon. NBAS and UPF1 coregulate the stability of ER-associated transcripts, in particular those associated with the cellular stress response. We propose a model where NBAS recruits UPF1 to the membrane of the ER and activates an ER-dedicated NMD pathway, thus providing an ER-protective function by ensuring quality control of ER-translated mRNAs.


Assuntos
Retículo Endoplasmático/metabolismo , Degradação do RNAm Mediada por Códon sem Sentido , Retículo Endoplasmático/enzimologia , Complexo de Golgi/metabolismo , Células HeLa , Humanos , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/fisiologia , Biossíntese de Proteínas , RNA Helicases/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(14): e2216700120, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36989302

RESUMO

Chromosome segregation during mitosis is highly regulated to ensure production of genetically identical progeny. Recurrent mitotic errors cause chromosomal instability (CIN), a hallmark of tumors. The E6 and E7 oncoproteins of high-risk human papillomavirus (HPV), which causes cervical, anal, and head and neck cancers (HNC), cause mitotic defects consistent with CIN in models of anogenital cancers, but this has not been studied in the context of HNC. Here, we show that HPV16 induces a specific type of CIN in patient HNC tumors, patient-derived xenografts, and cell lines, which is due to defects in chromosome congression. These defects are specifically induced by the HPV16 oncogene E6 rather than E7. We show that HPV16 E6 expression causes degradation of the mitotic kinesin CENP-E, whose depletion produces chromosomes that are chronically misaligned near spindle poles (polar chromosomes) and fail to congress. Though the canonical oncogenic role of E6 is the degradation of the tumor suppressor p53, CENP-E degradation and polar chromosomes occur independently of p53. Instead, E6 directs CENP-E degradation in a proteasome-dependent manner via the E6-associated ubiquitin protein ligase E6AP/UBE3A. This study reveals a mechanism by which HPV induces CIN, which may impact HPV-mediated tumor initiation, progression, and therapeutic response.


Assuntos
Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Humanos , Instabilidade Cromossômica , Cromossomos/metabolismo , Papillomavirus Humano 16/genética , Cinesinas/genética , Cinesinas/metabolismo , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
4.
Lancet ; 403(10432): 1164-1175, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38402887

RESUMO

BACKGROUND: Novel oral poliovirus vaccine type 2 (nOPV2) has been engineered to improve the genetic stability of Sabin oral poliovirus vaccine (OPV) and reduce the emergence of circulating vaccine-derived polioviruses. This trial aimed to provide key safety and immunogenicity data required for nOPV2 licensure and WHO prequalification. METHODS: This phase 3 trial recruited infants aged 18 to <52 weeks and young children aged 1 to <5 years in The Gambia. Infants randomly assigned to receive one or two doses of one of three lots of nOPV2 or one lot of bivalent OPV (bOPV). Young children were randomised to receive two doses of nOPV2 lot 1 or bOPV. The primary immunogenicity objective was to assess lot-to-lot equivalence of the three nOPV2 lots based on one-dose type 2 poliovirus neutralising antibody seroconversion rates in infants. Equivalence was declared if the 95% CI for the three pairwise rate differences was within the -10% to 10% equivalence margin. Tolerability and safety were assessed based on the rates of solicited adverse events to 7 days, unsolicited adverse events to 28 days, and serious adverse events to 3 months post-dose. Stool poliovirus excretion was examined. The trial was registered as PACTR202010705577776 and is completed. FINDINGS: Between February and October, 2021, 2345 infants and 600 young children were vaccinated. 2272 (96·9%) were eligible for inclusion in the post-dose one per-protocol population. Seroconversion rates ranged from 48·9% to 49·2% across the three lots. The minimum lower bound of the 95% CIs for the pairwise differences in seroconversion rates between lots was -5·8%. The maximum upper bound was 5·4%. Equivalence was therefore shown. Of those seronegative at baseline, 143 (85·6%) of 167 (95% CI 79·4-90·6) infants and 54 (83·1%) of 65 (71·7-91·2) young children seroconverted over the two-dose nOPV2 schedule. The post-two-dose seroprotection rates, including participants who were both seronegative and seropositive at baseline, were 604 (92·9%) of 650 (95% CI 90·7-94·8) in infants and 276 (95·5%) of 289 (92·4-97·6) in young children. No safety concerns were identified. 7 days post-dose one, 78 (41·7%) of 187 (95% CI 34·6-49·1) infants were excreting the type 2 poliovirus. INTERPRETATION: nOPV2 was immunogenic and safe in infants and young children in The Gambia. The data support the licensure and WHO prequalification of nOPV2. FUNDING: Bill & Melinda Gates Foundation.


Assuntos
Poliomielite , Poliovirus , Pré-Escolar , Humanos , Lactente , Anticorpos Antivirais , Formação de Anticorpos , Gâmbia , Esquemas de Imunização , Poliomielite/epidemiologia , Vacina Antipólio Oral
5.
Clin Infect Dis ; 78(2): 453-456, 2024 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-37805935

RESUMO

Chagas disease (CD), caused by Trypanosoma cruzi, is underdiagnosed in the United States. Improved screening strategies are needed, particularly for people at risk for life-threatening sequelae of CD, including people with human immunodeficiency virus (HIV, PWH). Here we report results of a CD screening strategy applied at a large HIV clinic serving an at-risk population.


Assuntos
Doença de Chagas , Infecções por HIV , Trypanosoma cruzi , Humanos , Estados Unidos/epidemiologia , HIV , Doença de Chagas/diagnóstico , Doença de Chagas/epidemiologia , Doença de Chagas/complicações , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/complicações
6.
Biol Reprod ; 109(6): 812-820, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-37688580

RESUMO

Embryo morphokinetic analysis through time-lapse embryo imaging is envisioned as a method to improve selection of developmentally competent embryos. Morphokinetic analysis could be utilized to evaluate the effects of experimental manipulation on pre-implantation embryo development. The objectives of this study were to establish a normative morphokinetic database for in vitro fertilized rhesus macaque embryos and to assess the impact of atypical initial cleavage patterns on subsequent embryo development and formation of embryo outgrowths. The cleavage pattern and the timing of embryo developmental events were annotated retrospectively for unmanipulated in vitro fertilized rhesus macaque blastocysts produced over four breeding seasons. Approximately 50% of the blastocysts analyzed had an abnormal early cleavage event. The time to the initiation of embryo compaction and the time to completion of hatching was significantly delayed in blastocysts with an abnormal early cleavage event compared to blastocysts that had cleaved normally. Embryo hatching, attachment to an extracellular matrix, and growth during the implantation stage in vitro was not impacted by the initial cleavage pattern. These data establish normative morphokinetic parameters for in vitro fertilized rhesus macaque embryos and suggest that cleavage anomalies may not impact embryo implantation rates following embryo transfer.


Assuntos
Desenvolvimento Embrionário , Fertilização in vitro , Animais , Macaca mulatta , Estudos Retrospectivos , Fertilização in vitro/veterinária , Fertilização in vitro/métodos , Embrião de Mamíferos , Implantação do Embrião , Blastocisto , Imagem com Lapso de Tempo/métodos , Técnicas de Cultura Embrionária/veterinária , Técnicas de Cultura Embrionária/métodos
7.
Exp Parasitol ; 249: 108519, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37004860

RESUMO

Leishmaniasis is a vector-borne neglected tropical disease caused by the Leishmania spp. Parasite. The disease is transmitted to humans and animals by the bite of infected female sandflies during the ingestion of bloodmeal. Because current drug treatments induce toxicity and parasite resistance, there is an urgent need to evaluate new drugs. Most therapeutics target the differentiation of promastigotes to amastigotes, which is necessary to maintain Leishmania infection. However, in vitro assays are laborious, time-consuming, and depend on the experience of the technician. In this study, we aimed to establish a short-term method to assess the differentiation status of Leishmania mexicana (L. mexicana) using flow cytometry. Here, we showed that flow cytometry provides a rapid means to quantify parasite differentiation in cell culture as reliably as light microscopy. Interestingly, we found using flow cytometry that miltefosine reduced promastigote-to-amastigote differentiation of L. mexicana. We conclude that flow cytometry provides a means to rapidly assay the efficacy of small molecules or natural compounds as potential anti-leishmanials.


Assuntos
Leishmania mexicana , Leishmania , Leishmaniose , Humanos , Animais , Feminino , Leishmania mexicana/fisiologia , Citometria de Fluxo , Diferenciação Celular
8.
Mol Plant Microbe Interact ; 35(3): 257-273, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34931906

RESUMO

The lipopolysaccharides (LPS) of gram-negative bacteria trigger a nitrosative and oxidative burst in both animals and plants during pathogen invasion. Liberibacter crescens strain BT-1 is a surrogate for functional genomic studies of the uncultured pathogenic 'Candidatus Liberibacter' spp. that are associated with severe diseases such as citrus greening and potato zebra chip. Structural determination of L. crescens LPS revealed the presence of a very long chain fatty acid modification. L. crescens LPS pretreatment suppressed growth of Xanthomonas perforans on nonhost tobacco (Nicotiana benthamiana) and X. citri subsp. citri on host orange (Citrus sinensis), confirming bioactivity of L. crescens LPS in activation of systemic acquired resistance (SAR). L. crescens LPS elicited a rapid burst of nitric oxide (NO) in suspension cultured tobacco cells. Pharmacological inhibitor assays confirmed that arginine-utilizing NO synthase (NOS) activity was the primary source of NO generation elicited by L. crescens LPS. LPS treatment also resulted in biological markers of NO-mediated SAR activation, including an increase in the glutathione pool, callose deposition, and activation of the salicylic acid and azelaic acid (AzA) signaling networks. Transient expression of 'Ca. L. asiaticus' bacterioferritin comigratory protein (BCP) peroxiredoxin in tobacco compromised AzA signaling, a prerequisite for LPS-triggered SAR. Western blot analyses revealed that 'Ca. L. asiaticus' BCP peroxiredoxin prevented peroxynitrite-mediated tyrosine nitration in tobacco. 'Ca. L. asiaticus' BCP peroxiredoxin (i) attenuates NO-mediated SAR signaling and (ii) scavenges peroxynitrite radicals, which would facilitate repetitive cycles of 'Ca. L. asiaticus' acquisition and transmission by fecund psyllids throughout the limited flush period in citrus.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Citrus , Rhizobiaceae , Proteínas de Bactérias , Citrus/microbiologia , Grupo dos Citocromos b , Ferritinas , Liberibacter , Lipopolissacarídeos/metabolismo , Estresse Nitrosativo , Peroxirredoxinas/metabolismo , Doenças das Plantas/microbiologia , Rhizobiaceae/metabolismo
9.
Eur J Neurosci ; 56(3): 4107-4120, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35703007

RESUMO

Neuroimaging studies using univariate and multivariate approaches have shown that the fusiform face area (FFA) and parahippocampal place area (PPA) respond selectively to images of faces and places. The aim of this study was to determine the extent to which this selectivity to faces or places is based on the shape or texture properties of the images. Faces and houses were filtered to manipulate their texture properties, while preserving the shape properties (spatial envelope) of the images. In Experiment 1, multivariate pattern analysis (MVPA) showed that patterns of fMRI response to faces and houses in FFA and PPA were predicted by the shape properties, but not by the texture properties of the image. In Experiment 2, a univariate analysis (fMR-adaptation) showed that responses in the FFA and PPA were sensitive to changes in both the shape and texture properties of the image. These findings can be explained by the spatial scale of the representation of images in the FFA and PPA. At a coarser scale (revealed by MVPA), the neural selectivity to faces and houses is sensitive to variation in the shape properties of the image. However, at a finer scale (revealed by fMR-adaptation), the neural selectivity is sensitive to the texture properties of the image. By combining these neuroimaging paradigms, our results provide insights into the spatial scale of the neural representation of faces and places in the ventral-temporal cortex.


Assuntos
Córtex Visual , Adaptação Fisiológica , Mapeamento Encefálico , Imageamento por Ressonância Magnética , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Córtex Visual/fisiologia
10.
Stem Cells ; 39(10): 1410-1422, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34028139

RESUMO

Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder characterized by the progressive loss of striatal medium spiny neurons. Using a highly efficient protocol for direct reprogramming of adult human fibroblasts with chemically modified mRNA, we report the first generation of HD induced neural precursor cells (iNPs) expressing striatal lineage markers that differentiated into DARPP32+ neurons from individuals with adult-onset HD (41-57 CAG). While no transcriptional differences between normal and HD reprogrammed neurons were detected by NanoString nCounter analysis, a subpopulation of HD reprogrammed neurons contained ubiquitinated polyglutamine aggregates. Importantly, reprogrammed HD neurons exhibited impaired neuronal maturation, displaying altered neurite morphology and more depolarized resting membrane potentials. Reduced BDNF protein expression in reprogrammed HD neurons correlated with increased CAG repeat lengths and earlier symptom onset. This model represents a platform for investigating impaired neuronal maturation and screening for neuronal maturation modifiers to treat HD.


Assuntos
Doença de Huntington , Células-Tronco Neurais , Corpo Estriado , Humanos , Doença de Huntington/metabolismo , Células-Tronco Neurais/metabolismo , Neurogênese , Neurônios/metabolismo
11.
Pediatr Nephrol ; 37(4): 821-832, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34608521

RESUMO

BACKGROUND: Wilms tumour (WT) survivors, especially patients with associated syndromes or genitourinary anomalies due to constitutional WT1 pathogenic variant, have increased risk of kidney failure. We describe the long-term kidney function in children with WT and WT1 pathogenic variant to inform the surgical strategy and oncological management of such complex children. METHODS: Retrospective analysis of patients with WT and constitutional WT1 pathogenic variant treated at a single centre between 1993 and 2016, reviewing genotype, phenotype, tumour histology, laterality, treatment, patient survival, and kidney outcome. RESULTS: We identified 25 patients (60% male, median age at diagnosis 14 months, range 4-74 months) with WT1 deletion (4), missense (2), nonsense (8), frameshift (7), or splice site (4) pathogenic variant. Thirteen (52%) had bilateral disease, 3 (12%) had WT-aniridia, 1 had incomplete Denys-Drash syndrome, 11 (44%) had genitourinary malformation, and 10 (40%) had no phenotypic anomalies. Patient survival was 100% and 3 patients were in remission after relapse at median follow-up of 9 years. Seven patients (28%) commenced chronic dialysis of which 3 were after bilateral nephrectomies. The overall kidney survival for this cohort as mean time to start of dialysis was 13.38 years (95% CI: 10.3-16.4), where 7 patients experienced kidney failure at a median of 5.6 years. All of these 7 patients were subsequently transplanted. In addition, 2 patients have stage III and stage IV chronic kidney disease and 12 patients have albuminuria and/or treatment with ACE inhibitors. Four patients (3 frameshift; 1 WT1 deletion) had normal blood pressure and kidney function without proteinuria at follow-up from 1.5 to 12 years. CONCLUSIONS: Despite the known high risk of kidney disease in patients with WT and constitutional WT1 pathogenic variant, nearly two-thirds of patients had sustained native kidney function, suggesting that nephron-sparing surgery (NSS) should be attempted when possible without compromising oncological risk. Larger international studies are needed for accurate assessment of WT1genotype-kidney function phenotype correlation.


Assuntos
Neoplasias Renais , Insuficiência Renal , Proteínas WT1 , Tumor de Wilms , Criança , Pré-Escolar , Feminino , Genes do Tumor de Wilms , Humanos , Lactente , Rim/patologia , Rim/cirurgia , Neoplasias Renais/genética , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Masculino , Mutação , Recidiva Local de Neoplasia/genética , Diálise Renal , Insuficiência Renal/genética , Estudos Retrospectivos , Proteínas WT1/genética , Tumor de Wilms/genética , Tumor de Wilms/patologia , Tumor de Wilms/cirurgia
12.
Ber Wiss ; 45(3): 317-331, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36086849

RESUMO

Employing and extending Hans-Jörg Rheinberger's analytical concept of epistemic things, this essay proposes one reason why squid giant axons, unusually large invertebrate nerve fibers, had such great impacts on twentieth-century neurobiology. The 1930s characterizations of these axons by John Zachary Young reshaped prevailing assumptions about nerve cells as epistemic things, I argue. Specifically, Young's preparations of these axons, which consisted of fibers attached to laboratory technologies, highlighted similarities between giant axons and more familiar ones via lines of comparative study common to aquatic biology. Young's work convinced other biologists that the squid giant fibers were, in fact, axons, despite their unusual fused (syncytial) structures, thereby promoting further studies, such as intracellular measurements, made possible by the fiber's size. Tracing direct relations between preparations of squid axons and broader interpretations of neurons as epistemic things, this paper renders an actors' category, "preparations," into an analytical one. In turn, it offers glimpses into how aquatic organisms shaped twentieth-century neurobiology and how local experiments can drive broader, disciplinary changes.


Assuntos
Decapodiformes , Neurobiologia , Animais , Axônios/fisiologia , Fibras Nervosas , Neurônios
13.
Plant J ; 102(2): 311-326, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31782853

RESUMO

The formation of nitrogen-fixing nodules on legume hosts is a finely tuned process involving many components of both symbiotic partners. Production of the exopolysaccharide succinoglycan by the nitrogen-fixing bacterium Sinorhizobium meliloti 1021 is needed for an effective symbiosis with Medicago spp., and the succinyl modification to this polysaccharide is critical. However, it is not known when succinoglycan intervenes in the symbiotic process, and it is not known whether the plant lysin-motif receptor-like kinase MtLYK10 intervenes in recognition of succinoglycan, as might be inferred from work on the Lotus japonicus MtLYK10 ortholog, LjEPR3. We studied the symbiotic infection phenotypes of S. meliloti mutants deficient in succinoglycan production or producing modified succinoglycan, in wild-type Medicago truncatula plants and in Mtlyk10 mutant plants. On wild-type plants, S. meliloti strains producing no succinoglycan or only unsuccinylated succinoglycan still induced nodule primordia and epidermal infections, but further progression of the symbiotic process was blocked. These S. meliloti mutants induced a more severe infection phenotype on Mtlyk10 mutant plants. Nodulation by succinoglycan-defective strains was achieved by in trans rescue with a Nod factor-deficient S. meliloti mutant. While the Nod factor-deficient strain was always more abundant inside nodules, the succinoglycan-deficient strain was more efficient than the strain producing only unsuccinylated succinoglycan. Together, these data show that succinylated succinoglycan is essential for infection thread formation in M. truncatula, and that MtLYK10 plays an important, but different role in this symbiotic process. These data also suggest that succinoglycan is more important than Nod factors for bacterial survival inside nodules.


Assuntos
Medicago truncatula/microbiologia , Proteínas de Plantas/metabolismo , Polissacarídeos Bacterianos/metabolismo , Sinorhizobium meliloti/fisiologia , Simbiose , Medicago truncatula/enzimologia , Medicago truncatula/genética , Peso Molecular , Mutação , Fixação de Nitrogênio , Fenótipo , Fosfotransferases/genética , Fosfotransferases/metabolismo , Proteínas de Plantas/genética , Polissacarídeos Bacterianos/genética , Nódulos Radiculares de Plantas/enzimologia , Nódulos Radiculares de Plantas/genética , Nódulos Radiculares de Plantas/microbiologia , Sinorhizobium meliloti/genética
14.
Mol Plant Microbe Interact ; 34(5): 461, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34138639

RESUMO

Plants live in a world filled with microbes, and spend their lives engaged in the delicate dance of nurturing beneficial interactions while simultaneously reducing disease-causing interactions. How do plants engage with beneficial microorganisms while at the same time restricting pathogens? was recently selected in a crowd-sourced effort as the top, unanswered question in the field of molecular plant-microbe interactions. Elaborating on this question and setting the stage for this focus issue, the Top10 review by Thoms, Liang and Haney examines the way multiple inputs are integrated to initiate programs of immunity or mutualistic symbiosis, and how this shapes the microbiome. This comprehensive review describes the current landscape of the field, focusing on the plant-microbe-soil continuum, but providing ideas for extending these concepts to leaves, where much of the research on immunity has centered. Other papers in this issue examine the simultaneous interaction of plants with beneficial and pathogenic microorganisms, as well as many diverse relationships with beneficial microbes that can improve plant health by increasing access to nutrients or by decreasing disease.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.


Assuntos
Microbiota , Plantas , Solo , Simbiose
15.
Mol Plant Microbe Interact ; 33(12): 1354-1365, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33106084

RESUMO

This article is part of the Top 10 Unanswered Questions in MPMI invited review series.The past few decades have seen major discoveries in the field of molecular plant-microbe interactions. As the result of technological and intellectual advances, we are now able to answer questions at a level of mechanistic detail that we could not have imagined possible 20 years ago. The MPMI Editorial Board felt it was time to take stock and reassess. What big questions remain unanswered? We knew that to identify the fundamental, overarching questions that drive our research, we needed to do this as a community. To reach a diverse audience of people with different backgrounds and perspectives, working in different areas of plant-microbe interactions, we queried the more than 1,400 participants at the 2019 International Congress on Molecular Plant-Microbe Interactions meeting in Glasgow. This group effort resulted in a list of ten, broad-reaching, fundamental questions that influence and inform our research. Here, we introduce these Top 10 unanswered questions, giving context and a brief description of the issues. Each of these questions will be the subject of a detailed review in the coming months. We hope that this process of reflecting on what is known and unknown and identifying the themes that underlie our research will provide a framework to use going forward, giving newcomers a sense of the mystery of the big questions and inspiring new avenues and novel insights.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.


Assuntos
Interações Hospedeiro-Patógeno , Plantas , Pesquisa , Interações Hospedeiro-Patógeno/genética , Plantas/genética , Plantas/microbiologia , Pesquisa/tendências
16.
Annu Rev Genomics Hum Genet ; 18: 389-415, 2017 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-28415857

RESUMO

The Human Genome Project modeled its open science ethos on nematode biology, most famously through daily release of DNA sequence data based on the 1996 Bermuda Principles. That open science philosophy persists, but daily, unfettered release of data has had to adapt to constraints occasioned by the use of data from individual people, broader use of data not only by scientists but also by clinicians and individuals, the global reach of genomic applications and diverse national privacy and research ethics laws, and the rising prominence of a diverse commercial genomics sector. The Global Alliance for Genomics and Health was established to enable the data sharing that is essential for making meaning of genomic variation. Data-sharing policies and practices will continue to evolve as researchers, health professionals, and individuals strive to construct a global medical and scientific information commons.


Assuntos
Genômica , Disseminação de Informação , Humanos , Modelos Animais , Patentes como Assunto
17.
J Neuroinflammation ; 17(1): 121, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32303238

RESUMO

BACKGROUND: After peripheral nerve transection, facial motoneuron (FMN) survival depends on an intact CD4+ T cell population and a central source of interleukin-10 (IL-10). However, it has not been determined previously whether CD4+ T cells participate in the central neuroprotective IL-10 cascade after facial nerve axotomy (FNA). METHODS: Immunohistochemical labeling of CD4+ T cells, pontine vasculature, and central microglia was used to determine whether CD4+ T cells cross the blood-brain barrier and enter the facial motor nucleus (FMNuc) after FNA. The importance of IL-10 signaling in CD4+ T cells was assessed by performing adoptive transfer of IL-10 receptor beta (IL-10RB)-deficient CD4+ T cells into immunodeficient mice prior to injury. Histology and qPCR were utilized to determine the impact of IL-10RB-deficient T cells on FMN survival and central gene expression after FNA. Flow cytometry was used to determine whether IL-10 signaling in T cells was necessary for their differentiation into neuroprotective subsets. RESULTS: CD4+ T cells were capable of crossing the blood-brain barrier and associating with reactive microglial nodules in the axotomized FMNuc. Full induction of central IL-10R gene expression after FNA was dependent on CD4+ T cells, regardless of their own IL-10R signaling capability. Surprisingly, CD4+ T cells lacking IL-10RB were incapable of mediating neuroprotection after axotomy and promoted increased central expression of genes associated with microglial activation, antigen presentation, T cell co-stimulation, and complement deposition. There was reduced differentiation of IL-10RB-deficient CD4+ T cells into regulatory CD4+ T cells in vitro. CONCLUSIONS: These findings support the interdependence of IL-10- and CD4+ T cell-mediated mechanisms of neuroprotection after axotomy. CD4+ T cells may potentiate central responsiveness to IL-10, while IL-10 signaling within CD4+ T cells is necessary for their ability to rescue axotomized motoneuron survival. We propose that loss of IL-10 signaling in CD4+ T cells promotes non-neuroprotective autoimmunity after FNA.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Traumatismos do Nervo Facial/metabolismo , Nervo Facial/metabolismo , Neurônios Motores/metabolismo , Receptores de Interleucina-10/biossíntese , Animais , Axotomia/métodos , Sobrevivência Celular/fisiologia , Células Cultivadas , Traumatismos do Nervo Facial/genética , Feminino , Expressão Gênica , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptores de Interleucina-10/genética
18.
Parasite Immunol ; 42(10): e12769, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32592180

RESUMO

E6020 is a synthetic agonist of Toll-like receptor-4 (TLR4). The purpose of this study was to evaluate the effect of different doses of E6020-SE on Trypanosoma cruzi-specific immune responses and its ability to confer protection against acute lethal infection in mice. Forty female BALB/c were infected with 500 trypomastigotes of T cruzi H1 strain, divided into four groups (n = 10) and treated at 7- and 14-day post-infection (dpi) with different doses of E6020-SE or PBS (control). Survival was followed for 51 days, mice were euthanized and hearts were collected to evaluate parasite burden, inflammation and fibrosis. We found significantly higher survival and lower parasite burdens in mice injected with E6020-SE at all doses compared to the control group. However, E6020-SE treatment did not significantly reduce cardiac inflammation or fibrosis. On the other hand, E6020-SE modulated Th1 and Th2 cytokines, decreasing IFN-γ and IL-4 in a dose-dependent manner after stimulation with parasite antigens. We conclude that E6020-SE alone increased survival by decreasing cardiac parasite burdens in BALB/c mice acutely infected with T cruzi but failed to prevent cardiac damage. Our results suggest that for optimal protection, a vaccine antigen is necessary to balance and orient a protective immune response.


Assuntos
Doença de Chagas/tratamento farmacológico , Fosfolipídeos/uso terapêutico , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Doença de Chagas/imunologia , Citocinas/imunologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Trypanosoma cruzi/imunologia
19.
BMC Pediatr ; 20(1): 557, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33317469

RESUMO

BACKGROUND: Previous research studies have demonstrated abnormalities in the metabolism of mothers of young children with autism. METHODS: Metabolic analysis was performed on blood samples from 30 mothers of young children with Autism Spectrum Disorder (ASD-M) and from 29 mothers of young typically-developing children (TD-M). Targeted metabolic analysis focusing on the folate one-carbon metabolism (FOCM) and the transsulfuration pathway (TS) as well as broad metabolic analysis were performed. Statistical analysis of the data involved both univariate and multivariate statistical methods. RESULTS: Univariate analysis revealed significant differences in 5 metabolites from the folate one-carbon metabolism and the transsulfuration pathway and differences in an additional 48 metabolites identified by broad metabolic analysis, including lower levels of many carnitine-conjugated molecules. Multivariate analysis with leave-one-out cross-validation allowed classification of samples as belonging to one of the two groups of mothers with 93% sensitivity and 97% specificity with five metabolites. Furthermore, each of these five metabolites correlated with 8-15 other metabolites indicating that there are five clusters of correlated metabolites. In fact, all but 5 of the 50 metabolites with the highest area under the receiver operating characteristic curve were associated with the five identified groups. Many of the abnormalities appear linked to low levels of folate, vitamin B12, and carnitine-conjugated molecules. CONCLUSIONS: Mothers of children with ASD have many significantly different metabolite levels compared to mothers of typically developing children at 2-5 years after birth.


Assuntos
Transtorno do Espectro Autista , Biomarcadores , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Ácido Fólico , Humanos , Mães
20.
Molecules ; 25(17)2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32854369

RESUMO

The arbocyclic nucleosides aristeromycin and neplanocin have been studied as a source for new antiviral agents. A convenient synthesis of C-5'-truncated 3-deaza-1',6'-isoneplanocin, which combines the features of antiviral candidates 5'-noraristeromycin and 3-deaza-1',6'-isoneplanocin is reported from (-)-cyclopentenone to give the two C-4' epimers of 5'-nor-3-deaza isoneplanocin. Antiviral assays showed activity against the JC virus (EC50 = 1.12 µM for (4'R)-8; EC50 = 59.14 µM for (4'S)-7) and inactivity of both compounds against several DNA and RNA viruses. Both compounds lacked cytotoxicity.


Assuntos
Adenosina , Antivirais , Vírus JC/crescimento & desenvolvimento , Vírus de RNA/crescimento & desenvolvimento , Adenosina/análogos & derivados , Adenosina/síntese química , Adenosina/química , Adenosina/farmacologia , Antivirais/síntese química , Antivirais/química , Antivirais/farmacologia , Humanos
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