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1.
Cell ; 183(3): 786-801.e19, 2020 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-33125893

RESUMO

Trained immunity, a functional state of myeloid cells, has been proposed as a compelling immune-oncological target. Its efficient induction requires direct engagement of myeloid progenitors in the bone marrow. For this purpose, we developed a bone marrow-avid nanobiologic platform designed specifically to induce trained immunity. We established the potent anti-tumor capabilities of our lead candidate MTP10-HDL in a B16F10 mouse melanoma model. These anti-tumor effects result from trained immunity-induced myelopoiesis caused by epigenetic rewiring of multipotent progenitors in the bone marrow, which overcomes the immunosuppressive tumor microenvironment. Furthermore, MTP10-HDL nanotherapy potentiates checkpoint inhibition in this melanoma model refractory to anti-PD-1 and anti-CTLA-4 therapy. Finally, we determined MTP10-HDL's favorable biodistribution and safety profile in non-human primates. In conclusion, we show that rationally designed nanobiologics can promote trained immunity and elicit a durable anti-tumor response either as a monotherapy or in combination with checkpoint inhibitor drugs.


Assuntos
Inibidores de Checkpoint Imunológico/uso terapêutico , Imunidade , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Nanotecnologia , Acetilmuramil-Alanil-Isoglutamina/metabolismo , Animais , Comportamento Animal , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Proliferação de Células/efeitos dos fármacos , Colesterol/metabolismo , Feminino , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Inibidores de Checkpoint Imunológico/farmacologia , Imunidade/efeitos dos fármacos , Imunoterapia , Lipoproteínas HDL/metabolismo , Camundongos Endogâmicos C57BL , Primatas , Distribuição Tecidual/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
2.
Cell ; 150(6): 1135-46, 2012 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-22980977

RESUMO

DNA methylation at the 5 position of cytosine (5-mC) is a key epigenetic mark that is critical for various biological and pathological processes. 5-mC can be converted to 5-hydroxymethylcytosine (5-hmC) by the ten-eleven translocation (TET) family of DNA hydroxylases. Here, we report that "loss of 5-hmC" is an epigenetic hallmark of melanoma, with diagnostic and prognostic implications. Genome-wide mapping of 5-hmC reveals loss of the 5-hmC landscape in the melanoma epigenome. We show that downregulation of isocitrate dehydrogenase 2 (IDH2) and TET family enzymes is likely one of the mechanisms underlying 5-hmC loss in melanoma. Rebuilding the 5-hmC landscape in melanoma cells by reintroducing active TET2 or IDH2 suppresses melanoma growth and increases tumor-free survival in animal models. Thus, our study reveals a critical function of 5-hmC in melanoma development and directly links the IDH and TET activity-dependent epigenetic pathway to 5-hmC-mediated suppression of melanoma progression, suggesting a new strategy for epigenetic cancer therapy.


Assuntos
Citosina/análogos & derivados , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Melanoma/genética , Nevo/genética , 5-Metilcitosina/análogos & derivados , Citosina/metabolismo , Proteínas de Ligação a DNA/genética , Dioxigenases , Estudo de Associação Genômica Ampla , Humanos , Isocitrato Desidrogenase/genética , Melanócitos/metabolismo , Melanoma/patologia , Nevo/patologia , Proteínas Proto-Oncogênicas/genética
3.
Brain ; 147(6): 2069-2084, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38763511

RESUMO

The peroxisomal disease adrenoleukodystrophy (X-ALD) is caused by loss of the transporter of very-long-chain fatty acids (VLCFAs), ABCD1. An excess of VLCFAs disrupts essential homeostatic functions crucial for axonal maintenance, including redox metabolism, glycolysis and mitochondrial respiration. As mitochondrial function and morphology are intertwined, we set out to investigate the role of mitochondrial dynamics in X-ALD models. Using quantitative 3D transmission electron microscopy, we revealed mitochondrial fragmentation in corticospinal axons in Abcd1- mice. In patient fibroblasts, an excess of VLCFAs triggers mitochondrial fragmentation through the redox-dependent phosphorylation of DRP1 (DRP1S616). The blockade of DRP1-driven fission by the peptide P110 effectively preserved mitochondrial morphology. Furthermore, mRNA inhibition of DRP1 not only prevented mitochondrial fragmentation but also protected axonal health in a Caenorhabditis elegans model of X-ALD, underscoring DRP1 as a potential therapeutic target. Elevated levels of circulating cell-free mtDNA in patients' CSF align this leukodystrophy with primary mitochondrial disorders. Our findings underscore the intricate interplay between peroxisomal dysfunction, mitochondrial dynamics and axonal integrity in X-ALD, shedding light on potential avenues for therapeutic intervention.


Assuntos
Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP , Adrenoleucodistrofia , Dinaminas , Dinâmica Mitocondrial , Adrenoleucodistrofia/metabolismo , Adrenoleucodistrofia/patologia , Adrenoleucodistrofia/genética , Animais , Dinâmica Mitocondrial/fisiologia , Humanos , Camundongos , Dinaminas/metabolismo , Dinaminas/genética , Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP/genética , Caenorhabditis elegans , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Axônios/patologia , Axônios/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Masculino , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Modelos Animais de Doenças , Tratos Piramidais/patologia , Tratos Piramidais/metabolismo , Fragmentos de Peptídeos , GTP Fosfo-Hidrolases
4.
Nano Lett ; 24(19): 5722-5728, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38712788

RESUMO

Quantum dots (QDs) with metal fluoride surface ligands were prepared via reaction with anhydrous oleylammonium fluoride. Carboxylate terminated II-VI QDs underwent carboxylate for fluoride exchange, while InP QDs underwent photochemical acidolysis yielding oleylamine, PH3, and InF3. The final photoluminescence quantum yield (PLQY) reached 83% for InP and near unity for core-shell QDs. Core-only CdS QDs showed dramatic improvements in PLQY, but only after exposure to air. Following etching, the InP QDs were bound by oleylamine ligands that were characterized by the frequency and breadth of the corresponding ν(N-H) bands in the infrared absorption spectrum. The fluoride content (1.6-9.2 nm-2) was measured by titration with chlorotrimethylsilane and compared with the oleylamine content (2.3-5.1 nm-2) supporting the formation of densely covered surfaces. The influence of metal fluoride adsorption on the air stability of QDs is discussed.

5.
Learn Mem ; 31(6)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38950977

RESUMO

Changes caused by learning that a food is inedible in Aplysia were examined for fast and slow synaptic connections from the buccal ganglia S1 cluster of mechanoafferents to five followers, in response to repeated stimulus trains. Learning affected only fast connections. For these, unique patterns of change were present in each follower, indicating that learning differentially affects the different branches of the mechanoafferents to their followers. In some followers, there were increases in either excitatory or inhibitory connections, and in others, there were decreases. Changes in connectivity resulted from changes in the amplitude of excitation or inhibition, or as a result of the number of connections, or of both. Some followers also exhibited changes in either within or between stimulus train plasticity as a result of learning. In one follower, changes differed from the different areas of the S1 cluster. The patterns of changes in connectivity were consistent with the behavioral changes produced by learning, in that they would produce an increase in the bias to reject or to release food, and a decrease in the likelihood to respond to food.


Assuntos
Aplysia , Gânglios dos Invertebrados , Neurônios Motores , Aplysia/fisiologia , Animais , Neurônios Motores/fisiologia , Gânglios dos Invertebrados/fisiologia , Aprendizagem/fisiologia , Mecanorreceptores/fisiologia , Plasticidade Neuronal/fisiologia , Alimentos , Comportamento Alimentar/fisiologia
6.
Learn Mem ; 31(6)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38950976

RESUMO

How does repeated stimulation of mechanoafferents affect feeding motor neurons? Monosynaptic connections from a mechanoafferent population in the Aplysia buccal ganglia to five motor followers with different functions were examined during repeated stimulus trains. The mechanoafferents produced both fast and slow synaptic outputs, which could be excitatory or inhibitory. In contrast, other Aplysia mechanoafferents produce only fast excitation on their followers. In addition, patterns of synaptic connections were different to the different motor followers. Some followers received both fast excitation and fast inhibition, whereas others received exclusively fast excitation. All followers showed strong decreases in fast postsynaptic potential (PSP) amplitude within a stimulus train. Fast and slow synaptic connections were of net opposite signs in some followers but not in others. For one follower, synaptic contacts were not uniform from all subareas of the mechanoafferent cluster. Differences in properties of the buccal ganglia mechanoafferents and other Aplysia mechanoafferents may arise because the buccal ganglia neurons innervate the interior of the feeding apparatus, rather than an external surface, and connect to motor neurons for muscles with different motor functions. Fast connection patterns suggest that these synapses may be activated when food slips, biasing the musculature to release food. The largest slow inhibitory synaptic PSPs may contribute to a delay in the onset of the next behavior. Additional functions are also possible.


Assuntos
Aplysia , Comportamento Alimentar , Gânglios dos Invertebrados , Neurônios Motores , Animais , Aplysia/fisiologia , Neurônios Motores/fisiologia , Gânglios dos Invertebrados/fisiologia , Comportamento Alimentar/fisiologia , Mecanorreceptores/fisiologia , Sinapses/fisiologia , Estimulação Física
7.
Plant Mol Biol ; 114(1): 4, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227103

RESUMO

Although many important discoveries have been made regarding the jasmonate signaling pathway, how jasmonate biosynthesis is initiated is still a major unanswered question in the field. Previous evidences suggest that jasmonate biosynthesis is limited by the availability of fatty acid precursor, such as ⍺-linolenic acid (⍺-LA). This indicates that the lipase responsible for releasing α-LA in the chloroplast, where early steps of jasmonate biosynthesis take place, is the key initial step in the jasmonate biosynthetic pathway. Nicotiana benthamiana glycerol lipase A1 (NbGLA1) is homologous to N. attenuata GLA1 (NaGLA1) which has been reported to be a major lipase in leaves for jasmonate biosynthesis. NbGLA1 was studied for its potential usefulness in a species that is more common in laboratories. Virus-induced gene silencing of both NbGLA1 and NbGLA2, another homolog, resulted in more than 80% reduction in jasmonic acid (JA) biosynthesis in wounded leaves. Overexpression of NbGLA1 utilizing an inducible vector system failed to increase JA, indicating that transcriptional induction of NbGLA1 is insufficient to trigger JA biosynthesis. However, co-treatment with wounding in addition to NbGLA1 induction increased JA accumulation several fold higher than the gene expression or wounding alone, indicating an enhancement of the enzyme activity by wounding. Domain-deletion of a 126-bp C-terminal region hypothesized to have regulatory roles increased NbGLA1-induced JA level. Together, the data show NbGLA1 to be a major lipase for wound-induced JA biosynthesis in N. benthamiana leaves and demonstrate the use of inducible promoter-driven construct of NbGLA1 in conjunction with its transient expression in N. benthamiana as a useful system to study its protein function.


Assuntos
Lipase , Nicotiana , Oxilipinas , Nicotiana/genética , Lipase/genética , Cloroplastos , Ciclopentanos , Glicerol
8.
Ann Surg ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916985

RESUMO

OBJECTIVE: To describe the evolution of pancreas transplantation, including improved outcomes and factors associated with improved outcomes over the past five decades. BACKGROUND: The world's first successful pancreas transplant was performed in December 1966 at the University of Minnesota. As new modalities for diabetes treatment mature, we must carefully assess the current state of pancreas transplantation to determine its ongoing role in patient care. METHODS: A single-center retrospective review of 2,500 pancreas transplants performed over >50 years in bivariate and multivariable models. Transplants were divided into six eras; outcomes are presented for the entire cohort and by era. RESULTS: All measures of patient and graft survival improved progressively through the six transplant eras. The overall death censored (DC) pancreas graft half-lives were >35 years for simultaneous pancreas and kidney (SPK), 7.1 years for pancreas after kidney (PAK), and 3.3 years for pancreas transplants alone (PTA). The 10-year DC pancreas graft survival rate in the most recent era was 86.9% for SPK recipients, 58.2% for PAK recipients, and 47.6% for PTA. Overall graft loss was most influenced by patient survival in SPK transplants, whereas graft loss in PAK and PTA recipients was more often due to graft failures. Predictors of improved pancreas graft survival were primary transplants, bladder drainage of exocrine secretions, younger donor age, and shorter preservation time. CONCLUSIONS: Pancreas outcomes have significantly improved over time via sequential, but overlapping, advances in surgical technique, immunosuppressive protocols, reduced preservation time, and the more recent reduction of immune-mediated graft loss.

9.
Immunity ; 42(5): 850-63, 2015 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25979419

RESUMO

The molecular mechanisms regulating antigen translocation into the cytosol for cross-presentation are under controversial debate, mainly because direct data is lacking. Here, we have provided direct evidence that the activity of the endoplasmic reticulum (ER) translocon protein Sec61 is essential for endosome-to-cytosol translocation. We generated a Sec61-specific intrabody, a crucial tool that trapped Sec61 in the ER and prevented its recruitment into endosomes without influencing Sec61 activity and antigen presentation in the ER. Expression of this ER intrabody inhibited antigen translocation and cross-presentation, demonstrating that endosomal Sec61 indeed mediates antigen transport across endosomal membranes. Moreover, we showed that the recruitment of Sec61 toward endosomes, and hence antigen translocation and cross-presentation, is dependent on dendritic cell activation by Toll-like receptor (TLR) ligands. These data shed light on a long-lasting question regarding antigen cross-presentation and point out a role of the ER-associated degradation machinery in compartments distinct from the ER.


Assuntos
Antígenos/metabolismo , Linfócitos T CD8-Positivos , Apresentação Cruzada/imunologia , Citosol/metabolismo , Endossomos/metabolismo , Proteínas de Membrana/metabolismo , Modelos Biológicos , Animais , Antígenos/imunologia , Linhagem Celular , Citosol/imunologia , Proteínas de Membrana/química , Camundongos , Transporte Proteico , Canais de Translocação SEC
10.
J Inherit Metab Dis ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38973597

RESUMO

The protein encoded by COQ7 is required for CoQ10 synthesis in humans, hydroxylating 3-demethoxyubiquinol (DMQ10) in the second to last steps of the pathway. COQ7 mutations lead to a primary CoQ10 deficiency syndrome associated with a pleiotropic neurological disorder. This study shows the clinical, physiological, and molecular characterization of four new cases of CoQ10 primary deficiency caused by five mutations in COQ7, three of which have not yet been described, inducing mitochondrial dysfunction in all patients. However, the specific combination of the identified variants in each patient generated precise pathophysiological and molecular alterations in fibroblasts, which would explain the differential in vitro response to supplementation therapy. Our results suggest that COQ7 dysfunction could be caused by specific structural changes that affect the interaction with COQ9 required for the DMQ10 presentation to COQ7, the substrate access to the active site, and the maintenance of the active site structure. Remarkably, patients' fibroblasts share transcriptional remodeling, supporting a modification of energy metabolism towards glycolysis, which could be an adaptive mechanism against CoQ10 deficiency. However, transcriptional analysis of mitochondria-associated pathways showed distinct and dramatic differences between patient fibroblasts, which correlated with the extent of pathophysiological and neurological alterations observed in the probands. Overall, this study suggests that the combination of precise genetic diagnostics and the availability of new structural models of human proteins could help explain the origin of phenotypic pleiotropy observed in some genetic diseases and the different responses to available therapies.

11.
Nature ; 559(7713): 236-240, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29995867

RESUMO

Controlled transport of water molecules through membranes and capillaries is important in areas as diverse as water purification and healthcare technologies1-7. Previous attempts to control water permeation through membranes (mainly polymeric ones) have concentrated on modulating the structure of the membrane and the physicochemical properties of its surface by varying the pH, temperature or ionic strength3,8. Electrical control over water transport is an attractive alternative; however, theory and simulations9-14 have often yielded conflicting results, from freezing of water molecules to melting of ice14-16 under an applied electric field. Here we report electrically controlled water permeation through micrometre-thick graphene oxide membranes17-21. Such membranes have previously been shown to exhibit ultrafast permeation of water17,22 and molecular sieving properties18,21, with the potential for industrial-scale production. To achieve electrical control over water permeation, we create conductive filaments in the graphene oxide membranes via controllable electrical breakdown. The electric field that concentrates around these current-carrying filaments ionizes water molecules inside graphene capillaries within the graphene oxide membranes, which impedes water transport. We thus demonstrate precise control of water permeation, from ultrafast permeation to complete blocking. Our work opens up an avenue for developing smart membrane technologies for artificial biological systems, tissue engineering and filtration.

12.
J Med Genet ; 60(4): 406-415, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36243518

RESUMO

BACKGROUND: Schaaf-Yang syndrome (SYS) is caused by truncating mutations in MAGEL2, mapping to the Prader-Willi region (15q11-q13), with an observed phenotype partially overlapping that of Prader-Willi syndrome. MAGEL2 plays a role in retrograde transport and protein recycling regulation. Our aim is to contribute to the characterisation of SYS pathophysiology at clinical, genetic and molecular levels. METHODS: We performed an extensive phenotypic and mutational revision of previously reported patients with SYS. We analysed the secretion levels of amyloid-ß 1-40 peptide (Aß1-40) and performed targeted metabolomic and transcriptomic profiles in fibroblasts of patients with SYS (n=7) compared with controls (n=11). We also transfected cell lines with vectors encoding wild-type (WT) or mutated MAGEL2 to assess stability and subcellular localisation of the truncated protein. RESULTS: Functional studies show significantly decreased levels of secreted Aß1-40 and intracellular glutamine in SYS fibroblasts compared with WT. We also identified 132 differentially expressed genes, including non-coding RNAs (ncRNAs) such as HOTAIR, and many of them related to developmental processes and mitotic mechanisms. The truncated form of MAGEL2 displayed a stability similar to the WT but it was significantly switched to the nucleus, compared with a mainly cytoplasmic distribution of the WT MAGEL2. Based on the updated knowledge, we offer guidelines for the clinical management of patients with SYS. CONCLUSION: A truncated MAGEL2 protein is stable and localises mainly in the nucleus, where it might exert a pathogenic neomorphic effect. Aß1-40 secretion levels and HOTAIR mRNA levels might be promising biomarkers for SYS. Our findings may improve SYS understanding and clinical management.


Assuntos
Síndrome de Prader-Willi , Humanos , Síndrome de Prader-Willi/genética , Fenótipo , Mutação , Proteínas/genética , Biomarcadores
13.
Blood Purif ; 53(2): 107-113, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37926072

RESUMO

INTRODUCTION: Midazolam-based continuous intravenous sedation in patients admitted to the intensive care unit (ICU) was a necessity during the COVID-19 pandemic. However, benzodiazepine-based sedation is associated with a high incidence of benzodiazepine-related delirium and additional days on mechanical ventilation. Due to the requirement of high midazolam doses in combination with the impaired renal clearance (CL) of the pharmacological active metabolite 1-OH-midazolam-glucuronide (10% compared to midazolam), ICU patients with COVID-19 and continuous renal replacement therapy (CRRT) were at risk of unintended prolonged sedation. Several CRRT-related factors may have influenced the delivered CL of midazolam and its metabolites. Therefore, the aim of the study was to identify and describe these CRRT-related factors. METHODS: Pre-filter blood samples and ultrafiltrate samples were collected simultaneously. Midazolam, 1-OH-midazolam, and 1-OH-midazolam-glucuronide plasma samples were analyzed using an UPLC-MS/MS method. The prescribed CRRT dose was corrected for downtime and filter integrity using the urea ratio (urea concentration in effluent/urea concentration plasma). CL of midazolam and its metabolites were calculated with the delivered CRRT dose (corrected for downtime and saturation coefficient [SD]). RESULTS: Three patients on continuous venovenous hemodialysis (CVVHD) and 2 patients on continuous venovenous hemodiafiltration (CVVHDF) were included. Midazolam, 1-OH-midazolam, and 1-OH-midazolam-glucuronide concentrations were 2,849 (0-6,700) µg/L, 153 (0-295) µg/L, and 27,297 (1,727-39,000) µg/L, respectively. The SD was 0.03 (0.02-0.03) for midazolam, 0.05 (0.05-0.06) for 1-OH-midazolam, and 0.33 (0.23-0.43) for 1-OH-midazolam-glucuronide. The delivered CRRT CL was 1.4 (0-1.7) mL/min for midazolam, 2.7 (0-3.5) mL/min for 1-OH-midazolam, and 15.7 (4.0-27.7) mL/min for 1-OH-midazolam-glucuronide. CONCLUSIONS: Midazolam and 1-OH-midazolam were not removed during CVVHD and CVVHDF. However, 1-OH-midazolam-glucuronide was removed reasonably, approximately up to 43%. CRRT modality, filter integrity, and downtime affect this removal. These data imply a personalized titration of midazolam in critically ill patients with renal failure and awareness for the additional sedative effects of its active metabolites.


Assuntos
Injúria Renal Aguda , COVID-19 , Terapia de Substituição Renal Contínua , Humanos , Midazolam/uso terapêutico , Estado Terminal/terapia , Cromatografia Líquida , Glucuronídeos , Pandemias , COVID-19/terapia , Espectrometria de Massas em Tandem , Ureia , Terapia de Substituição Renal
14.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34187879

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic is heterogeneous throughout Africa and threatening millions of lives. Surveillance and short-term modeling forecasts are critical to provide timely information for decisions on control strategies. We created a strategy that helps predict the country-level case occurrences based on cases within or external to a country throughout the entire African continent, parameterized by socioeconomic and geoeconomic variations and the lagged effects of social policy and meteorological history. We observed the effect of the Human Development Index, containment policies, testing capacity, specific humidity, temperature, and landlocked status of countries on the local within-country and external between-country transmission. One-week forecasts of case numbers from the model were driven by the quality of the reported data. Seeking equitable behavioral and social interventions, balanced with coordinated country-specific strategies in infection suppression, should be a continental priority to control the COVID-19 pandemic in Africa.


Assuntos
COVID-19/epidemiologia , COVID-19/transmissão , África/epidemiologia , COVID-19/diagnóstico , COVID-19/prevenção & controle , Previsões , Humanos , Modelos Estatísticos , Política Pública , SARS-CoV-2/isolamento & purificação , Tempo (Meteorologia)
15.
Learn Mem ; 30(11): 278-281, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37852783

RESUMO

An in vitro analog of learning that a food is inedible provided insight into mechanisms underlying the learning. Aplysia learn to stop responding to a food when they attempt but fail to swallow it. Pairing a cholinergic agonist with an NO donor or histamine in the Aplysia cerebral ganglion produced significant decreases in fictive feeding in response to the cholinergic agonist alone. Acetylcholine (ACh) is the transmitter of chemoreceptors sensing food touching the lips. Nitric oxide (NO) and histamine (HA) signal failed attempts to swallow food. Reduced responses to the cholinergic agonist after pairing with NO or HA indicate that learning partially arises via a decreased response to ACh in the cerebral ganglion.


Assuntos
Aplysia , Deglutição , Animais , Aplysia/fisiologia , Deglutição/fisiologia , Histamina , Comportamento Alimentar/fisiologia , Óxido Nítrico/fisiologia , Agonistas Colinérgicos
16.
J Neurosci ; 42(45): 8542-8555, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36198499

RESUMO

The oligodendrocyte (OL) lineage transcription factor Olig2 is expressed throughout oligodendroglial development and is essential for oligodendroglial progenitor specification and differentiation. It was previously reported that deletion of Olig2 enhanced the maturation and myelination of immature OLs and accelerated the remyelination process. However, by analyzing multiple Olig2 conditional KO mouse lines (male and female), we conclude that Olig2 has the opposite effect and is required for OL maturation and remyelination. We found that deletion of Olig2 in immature OLs driven by an immature OL-expressing Plp1 promoter resulted in defects in OL maturation and myelination, and did not enhance remyelination after demyelination. Similarly, Olig2 deletion during premyelinating stages in immature OLs using Mobp or Mog promoter-driven Cre lines also did not enhance OL maturation in the CNS. Further, we found that Olig2 was not required for myelin maintenance in mature OLs but was critical for remyelination after lysolecithin-induced demyelinating injury. Analysis of genomic occupancy in immature and mature OLs revealed that Olig2 targets the enhancers of key myelination-related genes for OL maturation from immature OLs. Together, by leveraging multiple immature OL-expressing Cre lines, these studies indicate that Olig2 is essential for differentiation and myelination of immature OLs and myelin repair. Our findings raise fundamental questions about the previously proposed role of Olig2 in opposing OL myelination and highlight the importance of using Cre-dependent reporter(s) for lineage tracing in studying cell state progression.SIGNIFICANCE STATEMENT Identification of the regulators that promote oligodendrocyte (OL) myelination and remyelination is important for promoting myelin repair in devastating demyelinating diseases. Olig2 is expressed throughout OL lineage development. Ablation of Olig2 was reported to induce maturation, myelination, and remyelination from immature OLs. However, lineage-mapping analysis of Olig2-ablated cells was not conducted. Here, by leveraging multiple immature OL-expressing Cre lines, we observed no evidence that Olig2 ablation promotes maturation or remyelination of immature OLs. Instead, we find that Olig2 is required for immature OL maturation, myelination, and myelin repair. These data raise fundamental questions about the proposed inhibitory role of Olig2 against OL maturation and remyelination. Our findings highlight the importance of validating genetic manipulation with cell lineage tracing in studying myelination.


Assuntos
Doenças Desmielinizantes , Remielinização , Animais , Feminino , Masculino , Camundongos , Diferenciação Celular , Doenças Desmielinizantes/metabolismo , Bainha de Mielina/metabolismo , Fator de Transcrição 2 de Oligodendrócitos/genética , Fator de Transcrição 2 de Oligodendrócitos/metabolismo , Oligodendroglia/metabolismo , Camundongos Knockout
17.
Crit Rev Clin Lab Sci ; 60(4): 270-289, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36694353

RESUMO

The currently available biomarkers generally lack the specificity and sensitivity needed for the diagnosis and follow-up of patients with mitochondrial diseases (MDs). In this group of rare genetic disorders (mutations in approximately 350 genes associated with MDs), all clinical presentations, ages of disease onset and inheritance types are possible. Blood, urine, and cerebrospinal fluid surrogates are well-established biomarkers that are used in clinical practice to assess MD. One of the main challenges is validating specific and sensitive biomarkers for the diagnosis of disease and prediction of disease progression. Profiling of lactate, amino acids, organic acids, and acylcarnitine species is routinely conducted to assess MD patients. New biomarkers, including some proteins and circulating cell-free mitochondrial DNA, with increased diagnostic specificity have been identified in the last decade and have been proposed as potentially useful in the assessment of clinical outcomes. Despite these advances, even these new biomarkers are not sufficiently specific and sensitive to assess MD progression, and new biomarkers that indicate MD progression are urgently needed to monitor the success of novel therapeutic strategies. In this report, we review the mitochondrial biomarkers that are currently analyzed in clinical laboratories, new biomarkers, an overview of the most common laboratory diagnostic techniques, and future directions regarding targeted versus untargeted metabolomic and genomic approaches in the clinical laboratory setting. Brief descriptions of the current methodologies are also provided.


Assuntos
Doenças Mitocondriais , Humanos , Seguimentos , Biomarcadores , Doenças Mitocondriais/diagnóstico , Doenças Mitocondriais/genética , Metabolômica/métodos , Aminoácidos
18.
Int J Cancer ; 152(10): 2109-2122, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36573352

RESUMO

Up to 50% of patients treated with curative esophagectomy for esophageal cancer will develop recurrence, contributing to the dismal survival associated with this disease. Regional recurrence may represent disease that is not yet widely metastatic and may therefore be amenable to more-aggressive treatment. We sought to assess all patients treated with curative esophagectomy for esophageal cancer who developed regional recurrence. We retrospectively identified all patients who underwent esophagectomy for esophageal adenocarcinoma and esophageal squamous cell carcinoma at a single institution from January 2000 to August 2019. In total, 1626 patients were included in the study cohort. As of June 2022, 595 patients had disease recurrence, which was distant or systemic in 435 patients (27%), regional in 125 (7.7%) and local in 35 (2.2%). On multivariable analysis, neoadjuvant chemoradiation with a total radiation dose <45 Gy (hazard ratio [HR], 3.5 [95% CI, 1.7-7.3]; P = .001), pathologic node-positive disease (HR, 1.9 [95% CI, 1.3-3.0]; P = .003) and lymphovascular invasion (HR, 1.6 [95% CI, 1.0-2.5]; P = .049) were predictors of isolated nodal recurrence, whereas increasing age (HR, 0.97 [95% CI, 0.96-0.99]; P = .001) and increasing number of excised lymph nodes (HR, 0.98 [95% CI, 0.95-1.00]; P = .021) were independently associated with decreased risk of regional recurrence. Patients treated with a combination of local and systemic therapies had better survival outcomes than patients treated with systemic therapy alone (P < .001). In patients with recurrence of esophageal cancer limited to regional lymph nodes, salvage treatment may be possible. Higher radiation doses and more-extensive lymphadenectomy may reduce the risk of regional recurrence.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Esofagectomia/efeitos adversos , Estudos Retrospectivos , Incidência , Carcinoma de Células Escamosas/patologia , Linfonodos/patologia , Excisão de Linfonodo/efeitos adversos , Recidiva Local de Neoplasia/patologia , Taxa de Sobrevida
19.
Ann Surg ; 277(3): e538-e544, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34387205

RESUMO

OBJECTIVE: To compare the efficacy and safety of induction FOLFOX followed by PET-directed nCRT, induction CP followed by PET-directed nCRT, and nCRT with CP alone in patients with EAC. SUMMARY OF BACKGROUND DATA: nCRT with CP is a standard treatment for locally advanced EAC. The results of cancer and leukemia group B 80803 support the use of induction chemotherapy followed by PET-directed chemo-radiation therapy. METHODS: We retrospectively identified all patients with EAC who underwent the treatments above followed by esophagectomy. We assessed incidences of pathologic complete response (pCR), near-pCR (ypN0 with ≥90% response), and surgical complications between treatment groups using Fisher exact test and logistic regression; disease-free survival (DFS) and overall survival (OS) were estimated by the Kaplan-Meier method and evaluated using the log-rank test and extended Cox regression. RESULTS: In total, 451 patients were included: 309 (69%) received induction chemotherapy before nCRT (FOLFOX, n = 70; CP, n = 239); 142 (31%) received nCRT with CP. Rates of pCR (33% vs. 16%, P = 0.004), near-pCR (57% vs. 33%, P < 0.001), and 2-year DFS (68% vs. 50%, P = 0.01) were higher in the induction FOLFOX group than in the induction CP group. Similarly, the rate of near-pCR (57% vs. 42%, P = 0.04) and 2-year DFS (68% vs. 44%, P < 0.001) were significantly higher in the FOLFOX group than in the no-induction group. CONCLUSIONS: Induction FOLFOX followed by PET-directed nCRT may result in better histopathologic response rates and DFS than either induction CP plus PET-directed nCRT or nCRT with CP alone.


Assuntos
Adenocarcinoma , Terapia Neoadjuvante , Humanos , Estudos Retrospectivos , Terapia Neoadjuvante/métodos , Quimiorradioterapia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/terapia , Tomografia por Emissão de Pósitrons
20.
Ann Surg ; 277(5): 781-788, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36727949

RESUMO

OBJECTIVE: To assess postoperative morbidity, disease-free survival (DFS), and overall survival (OS) in patients treated with salvage esophagectomy (SE). BACKGROUND DATA: A shift toward a "surgery as needed" approach for esophageal cancer has emerged, potentially resulting in delayed esophagectomy. METHODS: We identified patients with clinical stage I-III esophageal adenocarcinoma or squamous cell carcinoma who underwent chemoradiation followed by esophagectomy from 2001 to 2019. SE was defined as esophagectomy performed >90 days after chemoradiation ("for time") and esophagectomy performed for recurrence after curative-intent chemoradiation ("for recurrence"). The odds of postoperative serious complications were assessed by multivariable logistic regression. The relationship between SE and OS and DFS were quantified using Cox regression models. RESULTS: Of 1137 patients identified, 173 (15%) underwent SE. Of those, 61 (35%) underwent SE for recurrence, and 112 (65%) underwent SE for time. The odds of experiencing any serious complication [odds ratio, 2.10 (95% CI, 1.37-3.20); P =0.001] or serious pulmonary complication [odds ratio, 2.11 (95% CI, 1.31-3.42); P =0.002] were 2-fold higher for SE patients; SE patients had a 1.5-fold higher hazard of death [hazard ratio, 1.56 (95% CI, 1.25-1.94); P <0.0001] and postoperative recurrence [hazard ratio, 1.43 (95% CI, 1.16-1.77); P =0.001]. Five-year OS for nonsalvage esophagectomy was 45% [(95% CI, 41.6%-48.6%) versus 26.5% (95% CI, 20.2%-34.8%) for SE (log-rank P <0.001)]. Five-year OS for SE for time was 27.1% [(95% CI, 19.5%-37.5%) versus 25.2% (95% CI, 15.3%-41.5%) for SE for recurrence ( P =0.611)]. CONCLUSIONS: SE is associated with a higher risk of serious postoperative complications and shorter DFS and OS.


Assuntos
Adenocarcinoma , Carcinoma de Células Escamosas , Neoplasias Esofágicas , Humanos , Esofagectomia/métodos , Estudos Retrospectivos
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