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1.
Genes Dev ; 38(1-2): 11-30, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38182429

RESUMO

Amyotrophic lateral sclerosis (ALS) is a debilitating neurodegenerative disease characterized by loss of motor neurons. Human genetic studies have linked mutations in RNA-binding proteins as causative for this disease. The hnRNPA1 protein, a known pre-mRNA splicing factor, is mutated in some ALS patients. Here, two human cell models were generated to investigate how a mutation in the C-terminal low-complexity domain (LCD) of hnRNPA1 can cause splicing changes of thousands of transcripts that collectively are linked to the DNA damage response, cilium organization, and translation. We show that the hnRNPA1 D262V mutant protein binds to new binding sites on differentially spliced transcripts from genes that are linked to ALS. We demonstrate that this ALS-linked hnRNPA1 mutation alters normal RNA-dependent protein-protein interactions. Furthermore, cells expressing this hnRNPA1 mutant exhibit a cell aggregation phenotype, markedly reduced growth rates, changes in stress granule kinetics, and aberrant growth of neuronal processes. This study provides insight into how a single amino acid mutation in a splicing factor can alter RNA splicing networks of genes linked to ALS.


Assuntos
Esclerose Lateral Amiotrófica , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B , Doenças Neurodegenerativas , Humanos , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Mutação , Splicing de RNA/genética , Fatores de Processamento de RNA/genética
2.
Annu Rev Biochem ; 84: 291-323, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25784052

RESUMO

Precursor messenger RNA (pre-mRNA) splicing is a critical step in the posttranscriptional regulation of gene expression, providing significant expansion of the functional proteome of eukaryotic organisms with limited gene numbers. Split eukaryotic genes contain intervening sequences or introns disrupting protein-coding exons, and intron removal occurs by repeated assembly of a large and highly dynamic ribonucleoprotein complex termed the spliceosome, which is composed of five small nuclear ribonucleoprotein particles, U1, U2, U4/U6, and U5. Biochemical studies over the past 10 years have allowed the isolation as well as compositional, functional, and structural analysis of splicing complexes at distinct stages along the spliceosome cycle. The average human gene contains eight exons and seven introns, producing an average of three or more alternatively spliced mRNA isoforms. Recent high-throughput sequencing studies indicate that 100% of human genes produce at least two alternative mRNA isoforms. Mechanisms of alternative splicing include RNA-protein interactions of splicing factors with regulatory sites termed silencers or enhancers, RNA-RNA base-pairing interactions, or chromatin-based effects that can change or determine splicing patterns. Disease-causing mutations can often occur in splice sites near intron borders or in exonic or intronic RNA regulatory silencer or enhancer elements, as well as in genes that encode splicing factors. Together, these studies provide mechanistic insights into how spliceosome assembly, dynamics, and catalysis occur; how alternative splicing is regulated and evolves; and how splicing can be disrupted by cis- and trans-acting mutations leading to disease states. These findings make the spliceosome an attractive new target for small-molecule, antisense, and genome-editing therapeutic interventions.


Assuntos
Processamento Alternativo , Regulação da Expressão Gênica , Precursores de RNA/genética , Animais , Doença/genética , Humanos , Mutação , Splicing de RNA , RNA Catalítico/metabolismo , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Spliceossomos/química , Spliceossomos/efeitos dos fármacos
3.
Mol Cell ; 80(1): 156-163.e6, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33007255

RESUMO

The production of alternative RNA variants contributes to the tissue-specific regulation of gene expression. In the animal nervous system, a systematic shift toward distal sites of transcription termination produces transcript signatures that are crucial for neuron development and function. Here, we report that, in Drosophila, the highly conserved protein ELAV globally regulates all sites of neuronal 3' end processing and directly binds to proximal polyadenylation sites of target mRNAs in vivo. We uncover an endogenous strategy of functional gene rescue that safeguards neuronal RNA signatures in an ELAV loss-of-function context. When not directly repressed by ELAV, the transcript encoding the ELAV paralog FNE acquires a mini-exon, generating a new protein able to translocate to the nucleus and rescue ELAV-mediated alternative polyadenylation and alternative splicing. We propose that exon-activated functional rescue is a more widespread mechanism that ensures robustness of processes regulated by a hierarchy, rather than redundancy, of effectors.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Proteínas ELAV/metabolismo , Éxons/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Masculino , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma/genética
4.
Genes Dev ; 32(15-16): 1060-1074, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30042133

RESUMO

Alternative premessenger RNA (pre-mRNA) splicing is a post-transcriptional mechanism for controlling gene expression. Splicing patterns are determined by both RNA-binding proteins and nuclear pre-mRNA structure. Here, we analyzed pre-mRNA splicing patterns, RNA-binding sites, and RNA structures near these binding sites coordinately controlled by two splicing factors: the heterogeneous nuclear ribonucleoprotein hnRNPA1 and the RNA helicase DDX5. We identified thousands of alternative pre-mRNA splicing events controlled by these factors by RNA sequencing (RNA-seq) following RNAi. Enhanced cross-linking and immunoprecipitation (eCLIP) on nuclear extracts was used to identify protein-RNA-binding sites for both proteins in the nuclear transcriptome. We found a significant overlap between hnRNPA1 and DDX5 splicing targets and that they share many closely linked binding sites as determined by eCLIP analysis. In vivo SHAPE (selective 2'-hydroxyl acylation analyzed by primer extension) chemical RNA structure probing data were used to model RNA structures near several exons controlled and bound by both proteins. Both sequence motifs and in vivo UV cross-linking sites for hnRNPA1 and DDX5 were used to map binding sites in their RNA targets, and often these sites flanked regions of higher chemical reactivity, suggesting an organized nature of nuclear pre-mRNPs. This work provides a first glimpse into the possible RNA structures surrounding pre-mRNA splicing factor-binding sites.


Assuntos
Processamento Alternativo , RNA Helicases DEAD-box/metabolismo , Ribonucleoproteína Nuclear Heterogênea A1/metabolismo , Precursores de RNA/química , RNA Mensageiro/química , Sítios de Ligação , Núcleo Celular/genética , Núcleo Celular/metabolismo , Precursores de RNA/metabolismo , RNA Mensageiro/metabolismo
5.
Hepatology ; 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38385945

RESUMO

BACKGROUND AND AIMS: Metabolic dysfunction-associated steatotic liver disease (MASLD) encompasses a broad and continuous spectrum of liver diseases ranging from fatty liver to steatohepatitis. The intricate interactions of genetic, epigenetic, and environmental factors in the development and progression of MASLD remain elusive. Here, we aimed to achieve an integrative understanding of the genomic and transcriptomic alterations throughout the progression of MASLD. APPROACH AND RESULTS: RNA-Seq profiling (n = 146) and whole-exome sequencing (n = 132) of MASLD liver tissue samples identified 3 transcriptomic subtypes (G1-G3) of MASLD, which were characterized by stepwise pathological and molecular progression of the disease. Macrophage-driven inflammatory activities were identified as a key feature for differentiating these subtypes. This subtype-discriminating macrophage interplay was significantly associated with both the expression and genetic variation of the dsDNA sensor IFI16 (rs6940, A>T, T779S), establishing it as a fundamental molecular factor in MASLD progression. The in vitro dsDNA-IFI16 binding experiments and structural modeling revealed that the IFI16 variant exhibited increased stability and stronger dsDNA binding affinity compared to the wild-type. Further downstream investigation suggested that the IFI16 variant exacerbated DNA sensing-mediated inflammatory signals through mitochondrial dysfunction-related signaling of the IFI16-PYCARD-CASP1 pathway. CONCLUSIONS: This study unveils a comprehensive understanding of MASLD progression through transcriptomic classification, highlighting the crucial roles of IFI16 variants. Targeting the IFI16-PYCARD-CASP1 pathway may pave the way for the development of novel diagnostics and therapeutics for MASLD.

6.
Clin Infect Dis ; 78(3): 775-784, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-37815489

RESUMO

BACKGROUND: Pneumonia is a common cause of morbidity and mortality, yet a causative pathogen is identified in a minority of cases. Plasma microbial cell-free DNA sequencing may improve diagnostic yield in immunocompromised patients with pneumonia. METHODS: In this prospective, multicenter, observational study of immunocompromised adults undergoing bronchoscopy to establish a pneumonia etiology, plasma microbial cell-free DNA sequencing was compared to standardized usual care testing. Pneumonia etiology was adjudicated by a blinded independent committee. The primary outcome, additive diagnostic value, was assessed in the Per Protocol population (patients with complete testing results and no major protocol deviations) and defined as the percent of patients with an etiology of pneumonia exclusively identified by plasma microbial cell-free DNA sequencing. Clinical additive diagnostic value was assessed in the Per Protocol subgroup with negative usual care testing. RESULTS: Of 257 patients, 173 met Per Protocol criteria. A pneumonia etiology was identified by usual care in 52/173 (30.1%), plasma microbial cell-free DNA sequencing in 49/173 (28.3%) and the combination of both in 73/173 (42.2%) patients. Plasma microbial cell-free DNA sequencing exclusively identified an etiology of pneumonia in 21/173 patients (additive diagnostic value 12.1%, 95% confidence interval [CI], 7.7% to 18.0%, P < .001). In the Per Protocol subgroup with negative usual care testing, plasma microbial cell-free DNA sequencing identified a pneumonia etiology in 21/121 patients (clinical additive diagnostic value 17.4%, 95% CI, 11.1% to 25.3%). CONCLUSIONS: Non-invasive plasma microbial cell-free DNA sequencing significantly increased diagnostic yield in immunocompromised patients with pneumonia undergoing bronchoscopy and extensive microbiologic and molecular testing. CLINICAL TRIALS REGISTRATION: NCT04047719.


Assuntos
Pneumonia , Adulto , Humanos , Estudos Prospectivos , Pneumonia/etiologia , Análise de Sequência de DNA , Hospedeiro Imunocomprometido
7.
Hum Mol Genet ; 31(7): 1082-1095, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-34850884

RESUMO

Osteonecrosis of the femoral head (ONFH) involves necrosis of bone and bone marrow of the femoral head caused by ischemia with unknown etiology. Previous genetic studies on ONFH failed to produce consistent results, presumably because ONFH has various causes with different genetic backgrounds and the underlying diseases confounded the associations. Steroid-associated ONFH (S-ONFH) accounts for one-half of all ONFH, and systemic lupus erythematosus (SLE) is a representative disease underlying S-ONFH. We performed a genome-wide association study (GWAS) to identify genetic risk factors for S-ONFH in patients with SLE. We conducted a two-staged GWAS on 636 SLE patients with S-ONFH and 95 588 non-SLE controls. Among the novel loci identified, we determined S-ONFH-specific loci by comparing allele frequencies between SLE patients without S-ONFH and non-SLE controls. We also used Korean datasets comprising 148 S-ONFH cases and 37 015 controls to assess overall significance. We evaluated the functional annotations of significant variants by in silico analyses. The Japanese GWAS identified 4 significant loci together with 12 known SLE susceptibility loci. The four significant variants showed comparable effect sizes on S-ONFH compared with SLE controls and non-SLE controls. Three of the four loci, MIR4293/MIR1265 [odds ratio (OR) = 1.99, P-value = 1.1 × 10-9)], TRIM49/NAALAD2 (OR = 1.65, P-value = 4.8 × 10-8) and MYO16 (OR = 3.91, P-value = 4.9 × 10-10), showed significant associations in the meta-analysis with Korean datasets. Bioinformatics analyses identified MIR4293, NAALAD2 and MYO16 as candidate causal genes. MIR4293 regulates a PPARG-related adipogenesis pathway relevant to S-ONFH. We identified three novel susceptibility loci for S-ONFH in SLE.


Assuntos
Necrose da Cabeça do Fêmur , Lúpus Eritematoso Sistêmico , Esteroides , Carboxipeptidases/genética , Proteínas de Transporte/genética , Cabeça do Fêmur , Necrose da Cabeça do Fêmur/induzido quimicamente , Necrose da Cabeça do Fêmur/complicações , Necrose da Cabeça do Fêmur/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Lúpus Eritematoso Sistêmico/genética , MicroRNAs/genética , Cadeias Pesadas de Miosina/genética , Polimorfismo de Nucleotídeo Único , Esteroides/efeitos adversos
8.
Artigo em Inglês | MEDLINE | ID: mdl-39218203

RESUMO

OBJECTIVE: AMP-activated protein kinase (AMPK) dysregulation is implicated in osteoarthritis (OA), but the mechanisms underlying this dysregulation remain unclear. We investigated the role of cereblon, a substrate-recognition protein within the E3-ligase ubiquitin complex, in AMPK dysregulation and OA pathogenesis. METHODS: Cereblon expression was examined in human (n = 5) and mouse (n = 10) OA cartilage. The role of cereblon was investigated through its adenoviral overexpression (n = 10) or knockout (KO, n = 15) in the destabilization of the medial meniscus (DMM)-operated mice. The therapeutic potentials of the chemical cereblon degrader, TD-165, and the AMPK activator, metformin, were assessed through intra-articular (IA) injection to mice (n = 15). RESULTS: Immunostaining revealed that cereblon is upregulated in human and mouse OA cartilage. In DMM model mice, cartilage destruction was exacerbated by overexpression of cereblon in mouse joint tissues (OARSI grade; 1.11 [95% CI: 0.50 to 2.75]), but inhibited in global (-2.50 [95% CI: -3.00 to -1.17]) and chondrocyte-specific (-2.17 [95% CI: -3.14 to -1.06]) cereblon KO mice. The inhibitory effects were more pronounced in mice fed a high-fat diet compared to a regular diet. The degradation of cereblon through IA injection of TD-165 inhibited OA cartilage destruction (-2.47 [95% CI: -3.22 to -1.56]). Mechanistically, cereblon exerts its catabolic effects by negatively modulating AMPK activity within chondrocytes. Consistently, activation of AMPK by IA injection of metformin inhibited posttraumatic OA cartilage destruction (-1.20 ([95% CI: -1.89 to -0.45]). CONCLUSIONS: The cereblon-AMPK axis acts as a catabolic regulator of OA pathogenesis and seems to be a promising therapeutic target in animal models of OA.

9.
FASEB J ; 37(2): e22763, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36625326

RESUMO

Diabetic retinopathy (DR) is caused by retinal vascular dysfunction and neurodegeneration. Intraocular delivery of C-peptide has been shown to be beneficial against hyperglycemia-induced microvascular leakage in the retina of diabetes; however, the effect of C-peptide on diabetes-induced retinal neurodegeneration remains unknown. Moreover, extraocular C-peptide replacement therapy against DR to avoid various adverse effects caused by intravitreal injections has not been studied. Here, we demonstrate that systemic C-peptide supplementation using osmotic pumps or biopolymer-conjugated C-peptide hydrogels ameliorates neurodegeneration by inhibiting vascular endothelial growth factor-induced pathological events, but not hyperglycemia-induced vascular endothelial growth factor expression, in the retinas of diabetic mice. C-peptide inhibited hyperglycemia-induced activation of macroglial and microglial cells, downregulation of glutamate aspartate transporter 1 expression, neuronal apoptosis, and histopathological changes by a mechanism involving reactive oxygen species generation in the retinas of diabetic mice, but transglutaminase 2, which is involved in retinal vascular leakage, is not associated with these pathological events. Overall, our findings suggest that systemic C-peptide supplementation alleviates hyperglycemia-induced retinal neurodegeneration by inhibiting a pathological mechanism, involving reactive oxygen species, but not transglutaminase 2, in diabetes.


Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , Hiperglicemia , Animais , Camundongos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Peptídeo C/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Retina/metabolismo , Fatores de Crescimento do Endotélio Vascular , Retinopatia Diabética/metabolismo , Hiperglicemia/metabolismo , Suplementos Nutricionais
10.
Brain Behav Immun ; 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39284516

RESUMO

Synucleinopathies are age-related neurological disorders characterized by the abnormal accumulation of α-synuclein (α-syn) in neuronal and non-neuronal cells. It has been proposed that microglial cells play an important role in synucleinopathy neuroinflammation, as well as homeostatically, such as in the clearance of α-syn aggregates in the brain. Here, we examined the effects of microglia on the pathogenesis of synucleinopathies by cell depletion in a mouse model of synucleinopathies. For this purpose, we treated non-transgenic (Non-tg) and α-synuclein transgenic (α-syn-tg) mice with pexidartinib (PLX3397), a tyrosine kinase inhibitor of colony-stimulating factor 1 receptor (CSF-1R). Neuropathological and immunoblot analysis confirmed that Iba-1 immunoreactive microglial cells were decreased by 95% following PLX3397 treatment in Non-tg and α-syn-tg mice. The level of total α-syn in the Triton X-insoluble fraction of brain homogenate was significantly decreased by microglial depletion in the α-syn-tg mice, while the level of Triton X-soluble human α-syn was not affected. Furthermore, the number of p-α-syn immunoreactive inclusions was reduced in α-syn-tg mice treated with PLX3397. Microglial depletion also ameliorated neuronal and synaptic degeneration in α-syn-tg mice, thereby resulted partially improving the motor behavioral deficit in α-syn-tg mice. Moreover, we demonstrated that microglia that survived post-PLX3397 treatment (PLX-resistant microglia) have lower expressions of CSF-1R, and microglial transcriptome analysis further elucidated that PLX-resistant microglia have unique morphology and transcriptomic signatures relative to vehicle-treated microglia of both genotypes; these include differences in definitive microglial functions such as their immune response, cell mobility, cell-cell communications, and regulation of neural homeostasis. Therefore, we suggest that microglia play a critical role in the pathogenesis of synucleinopathies, and that modulation of microglial status might be an effective therapeutic strategy for synucleinopathies.

11.
Neuroepidemiology ; : 1-9, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38952140

RESUMO

BACKGROUND: Smoking is a well-known risk factor for cardiovascular diseases, including myocardial infarction (MI) and ischemic stroke (IS). While the relationship between smoking and the risk of cardiovascular diseases is established, the impact of changing smoking habits post-IS on the risk of subsequent MI remains unclear. This study aims to elucidate the effects of alterations in smoking behavior following an IS diagnosis on the likelihood of experiencing an MI. METHODS: Utilizing data from the Korean National Health Insurance Services Database, this nationwide population-based cohort study included 199,051 participants diagnosed with IS between January 2010 and December 2016. Smoking status was categorized based on changes in smoking habits before and after IS diagnosis. The association between changes in smoking behavior and the risk of subsequent MI was analyzed using multivariable Cox proportional hazard regression models. RESULTS: During a median follow-up of 4.17 person-years, a total of 5,734 (2.88%) patients were diagnosed with MI after IS. Smoking quitters (2.93%) or former smokers (2.47%) have a similar or lower rate of MI than the average, even if they have smoked cigarettes, while sustained smokers (3.46%) or new smokers (3.81%) have much higher rates of MI. Among sustained and new smokers, the risk of incident MI was significantly higher than never smokers (new smoker adjusted HR [aHR]: 1.496, 95% CI: 1.262-1.774; sustained smoker aHR: 1.494, 95% CI: 1.361-1.641). Also, among the study participants, approximately two-thirds continued smoking after their IS diagnosis. CONCLUSION: Changing smoking habits after an IS diagnosis significantly influences the risk of subsequent MI. Specifically, continuing or starting to smoke after an IS diagnosis is associated with a higher risk of MI. These results underscore the importance of targeted smoking cessation interventions for stroke patients to reduce the risk of subsequent MI.

12.
Gynecol Oncol ; 189: 64-67, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39029275

RESUMO

Asian American and Pacific Islanders (AAPI) are the fastest growing racial group in the United States. Data on AAPI communities, however, are significantly limited. The oversimplification and underreporting of this ethnically and socioeconomically heterogenous population through the use of aggregated data has deleterious effects and worsens disparities in patient treatment, outcomes, and experiences. Gynecologic oncology disparities do not exist in a vacuum, and are rooted in larger cultural gaps in our understanding and delivery of healthcare. In this paper, we aim to demonstrate how AAPI data inequities have negative downstream effects on research and public health policies and initiatives, and also provide a call to action with specific recommendations on how to improve AAPI data equity within these realms.


Assuntos
Nativo Asiático-Americano do Havaí e das Ilhas do Pacífico , Neoplasias dos Genitais Femininos , Disparidades em Assistência à Saúde , Feminino , Humanos , Neoplasias dos Genitais Femininos/etnologia , Neoplasias dos Genitais Femininos/terapia , Ginecologia/estatística & dados numéricos , Disparidades em Assistência à Saúde/etnologia , Disparidades em Assistência à Saúde/estatística & dados numéricos , Oncologia/estatística & dados numéricos , Estados Unidos
13.
J Surg Res ; 298: 325-334, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38657351

RESUMO

INTRODUCTION: The tall cell, columnar, and diffuse sclerosing subtypes are aggressive histologic subtypes of papillary thyroid cancer (PTC) with increasing incidence, yet there is a wide variation in reporting. We aimed to identify and compare factors associated with the reporting of these aggressive subtypes (aPTC) to classic PTC (cPTC) and secondarily identify differences in outcomes. METHODS: The National Cancer Database was utilized to identify cPTC and aPTC from 2004 to 2017. Patient and facility demographics and clinicopathologic variables were analyzed. Independent predictors of aPTC reporting were identified and a survival analysis was performed. RESULTS: The majority of aPTC (67%) were reported by academic facilities. Compared to academic facilities, all other facility types were 1.4-2.0 times less likely to report aPTC (P < 0.05). Regional variation in reporting was noted, with more cases reported in the Middle Atlantic, despite there being more total facilities in the South Atlantic and East North Central regions. Compared to the Middle Atlantic, all other regions were 1.4-5 times less likely to report aPTC (P < 0.001). Patient characteristics including race and income were not associated with aPTC reporting. Compared to cPTC, aPTC had higher rates of aggressive features and worse 5-y overall survival (90.5% versus 94.5%, log rank P < 0.001). CONCLUSIONS: Aggressive subtypes of PTC are associated with worse outcomes. Academic and other facilities in the Middle Atlantic were more likely to report aPTC. This suggests the need for further evaluation of environmental or geographic factors versus a need for increased awareness and more accurate diagnosis of these subtypes.


Assuntos
Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/patologia , Câncer Papilífero da Tireoide/mortalidade , Feminino , Masculino , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/mortalidade , Neoplasias da Glândula Tireoide/epidemiologia , Pessoa de Meia-Idade , Adulto , Idoso , Estados Unidos/epidemiologia , Estudos Retrospectivos , Bases de Dados Factuais/estatística & dados numéricos
14.
Microb Cell Fact ; 23(1): 122, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678199

RESUMO

BACKGROUND: Industrial biomanufacturing of value-added products using CO2 as a carbon source is considered more sustainable, cost-effective and resource-efficient than using common carbohydrate feedstocks. Cupriavidus necator H16 is a representative H2-oxidizing lithoautotrophic bacterium that can be utilized to valorize CO2 into valuable chemicals and has recently gained much attention as a promising platform host for versatile C1-based biomanufacturing. Since this microbial platform is genetically tractable and has a high-flux carbon storage pathway, it has been engineered to produce a variety of valuable compounds from renewable carbon sources. In this study, the bacterium was engineered to produce resveratrol autotrophically using an artificial phenylpropanoid pathway. RESULTS: The heterologous genes involved in the resveratrol biosynthetic pathway-tyrosine ammonia lyase (TAL), 4-coumaroyl CoA ligase (4CL), and stilbene synthase (STS) -were implemented in C. necator H16. The overexpression of acetyl-CoA carboxylase (ACC), disruption of the PHB synthetic pathway, and an increase in the copy number of STS genes enhanced resveratrol production. In particular, the increased copies of VvSTS derived from Vitis vinifera resulted a 2-fold improvement in resveratrol synthesis from fructose. The final engineered CR-5 strain produced 1.9 mg/L of resveratrol from CO2 and tyrosine via lithoautotrophic fermentation. CONCLUSIONS: To the best of our knowledge, this study is the first to describe the valorization of CO2 into polyphenolic compounds by engineering a phenylpropanoid pathway using the lithoautotrophic bacterium C. necator H16, demonstrating the potential of this strain a platform for sustainable chemical production.


Assuntos
Dióxido de Carbono , Cupriavidus necator , Fermentação , Engenharia Metabólica , Resveratrol , Cupriavidus necator/metabolismo , Cupriavidus necator/genética , Resveratrol/metabolismo , Dióxido de Carbono/metabolismo , Engenharia Metabólica/métodos , Aciltransferases/genética , Aciltransferases/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Amônia-Liases/metabolismo , Amônia-Liases/genética , Vias Biossintéticas
15.
J Nat Prod ; 87(2): 358-364, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38320400

RESUMO

Bioassay-guided isolation of the extract from the marine sponge Diacarnus spinipoculum showing inhibitory activity against human transient receptor potential ankyrin 1 (hTRPA1) resulted in the isolation of 12 norditerpene cyclic peroxides (1-12) and eight norsesterterpene cyclic peroxides (13-20). Among these, 10 (5-7, 11, 12, 16-20) are unprecedented analogs. Compounds with either a hydroxy (5, 11) or a methoxy (6, 12) group attached to the cyclohexanone moiety were obtained as epimeric mixtures at C-11, while compounds 4, 6, 10, and 12 are likely the artifacts of isolation. The absolute configurations of the new compounds were established based on an NMR-based empirical method and comparison of specific rotation values. Mosher ester analysis revealed the absolute configurations of compounds 17-20. The inhibitory activity of the isolated compounds against hTRPA1 varied significantly depending on their structures, with the norsesterterpenoid 19 displaying the most potent activity (IC50 2.0 µM).


Assuntos
Diterpenos , Poríferos , Animais , Humanos , Anquirinas/antagonistas & inibidores , Estrutura Molecular , Peróxidos/farmacologia , Peróxidos/química , Poríferos/química , Terpenos/farmacologia , Terpenos/química
16.
J Pediatr Hematol Oncol ; 46(2): e143-e146, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38237014

RESUMO

Isavuconazonium sulfate (ISA) is a triazole antifungal approved for the treatment of invasive aspergillosis and mucormycosis in adults. This single-center, retrospective review of pediatric oncology and stem cell transplant patients receiving ISA for prophylaxis (n=20) or treatment (n=6) of invasive fungal disease (IFD) aims to characterize real-world clinical efficacy and toxicity of ISA in patients <18 years of age. Of 20 patients receiving ISA for prophylaxis, three patients had presumed breakthrough IFD (1 proven, 2 probable/possible). No adverse effects were attributed to ISA use or led to the discontinuation of therapy.


Assuntos
Infecções Fúngicas Invasivas , Neoplasias , Nitrilas , Piridinas , Adulto , Criança , Humanos , Estudos Retrospectivos , Antifúngicos , Infecções Fúngicas Invasivas/tratamento farmacológico , Triazóis , Transplante de Células-Tronco , Neoplasias/tratamento farmacológico
17.
Surg Endosc ; 38(2): 1020-1028, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38097749

RESUMO

INTRODUCTION: Endoluminal functional lumen imaging probe (EndoFLIP) provides a real-time assessment of gastroesophageal junction (GEJ) compliance during fundoplication. Given the limited data on EndoFLIP measurements during the Hill procedure, we investigated the impact of the Hill procedure on GEJ compliance compared to Toupet fundoplication. METHODS: Patients who underwent robotic Hill or Toupet fundoplication with intraoperative EndoFLIP between 2017 and 2022 were included. EndoFLIP measurements of the GEJ included cross sectional surface area (CSA), intra-balloon pressure, high pressure zone length (HPZ), distensibility index (DI), and compliance. Subjective reflux symptoms, gastroesophageal reflux disease-health related quality of life (GERD-HRQL) score, and dysphagia score were assessed pre-operatively as well as at short- and longer-term follow-up. RESULTS: One-hundred and fifty-four patients (71.9%) had a Toupet fundoplication while sixty (28%) patients underwent the Hill procedure. The CSA [27.7 ± 10.9 mm2 vs 42.2 ± 17.8 mm2, p < 0.0001], pressure [29.5 ± 6.2 mmHg vs 33.9 ± 8.5 mmHg, p = 0.0009], DI [0.9 ± 0.4 mm2/mmHg vs 1.3 ± 0.6 mm2/mmHg, p = 0.001], and compliance [25.9 ± 12.8 mm3/mmHg vs 35.4 ± 13.4 mm3/mmHg, p = 0.01] were lower after the Hill procedure compared to Toupet. However, there was no difference in post-fundoplication HPZ between procedures [Hill: 2.9 ± 0.4 cm, Toupet: 3.1 ± 0.6 cm, p = 0.15]. Follow-up showed no significant differences in GERD-HRQL scores, overall dysphagia scores or atypical symptoms between groups (p > 0.05). CONCLUSION: The Hill procedure is as effective to the Toupet fundoplication in surgically treating gastroesophageal reflux disease (GERD) despite the lower CSA, DI, and compliance after the Hill procedure. Both procedures led to DI < 2 mm2/mmHg with no significant differences in dysphagia reporting (12-24) months after the procedure. Further studies to elucidate a cutoff value for DI for postoperative dysphagia development are still warranted.


Assuntos
Transtornos de Deglutição , Refluxo Gastroesofágico , Laparoscopia , Humanos , Fundoplicatura/métodos , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/cirurgia , Impedância Elétrica , Qualidade de Vida , Estudos Transversais , Laparoscopia/métodos , Refluxo Gastroesofágico/diagnóstico , Refluxo Gastroesofágico/cirurgia , Resultado do Tratamento
18.
BMC Pulm Med ; 24(1): 7, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166950

RESUMO

BACKGROUND: Bacterial colonization is an essential aspect of bronchiectasis. Although Haemophilus influenzae is a frequent colonizer in some regions, its clinical impacts are poorly understood. This study aimed to elucidate the impact of H. influenzae colonization in patients with bronchiectasis. METHODS: This retrospective study screened adult patients diagnosed with bronchiectasis at a tertiary referral center between April 1, 2003, and May 16, 2021, in South Korea. Propensity score matching was used to match patients with and without H. influenzae colonization. We assessed the severity of bronchiectasis as per the bronchiectasis severity index, the incidence of exacerbation, differences in lung function, and all-cause mortality. RESULTS: Out of the 4,453 patients with bronchiectasis, 79 (1.8%) were colonized by H. influenzae. After 1:2 propensity score matching, 78 and 154 patients were selected from the H. influenzae colonizer and non-colonizer groups, respectively. Although there were no significant differences between the groups regarding baseline demographics, patients colonized with H. influenzae had a higher bronchiectasis severity index (median 6 [interquartile range 4-8] vs. 4 [2-7], p = 0.002), associated with extensive radiographic involvement (52.2% vs. 37.2%, p = 0.045) and mild exacerbation without hospitalization (adjusted incidence rate ratio 0.15; 95% confidence interval 0.12-0.24). Lung function and mortality rates did not reveal significant differences, regardless of H. influenzae colonization. CONCLUSION: H. influenzae colonization in bronchiectasis was associated with more severe disease and greater incidence of mild exacerbation, but not lung function and mortality. Attention should be paid to patients with bronchiectasis with H. influenzae colonization.


Assuntos
Bronquiectasia , Haemophilus influenzae , Adulto , Humanos , Estudos Retrospectivos , Bronquiectasia/complicações , República da Coreia/epidemiologia
19.
BMC Public Health ; 24(1): 1241, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711032

RESUMO

BACKGROUND: The impact of changes in physical activity after ischemic stroke (IS) on the subsequent myocardial infarction (MI) risk is not fully understood. We aimed to investigate the effects of changes in physical activity on the risk of MI after acute IS using data from the Korean National Health Insurance Services Database. METHODS: 224,764 patients newly diagnosed with IS between 2010 and 2016 who underwent two serial biannual health checkups were included. The participants were divided into four categories according to changes in their physical activity: persistent non-exercisers, new exercisers, exercise dropouts, and exercise maintainers. The primary outcome was a new diagnosis of incident MI. Multivariable Cox proportional models were used to assess the effects of changes in exercise habits on the risk of MI. RESULTS: After a median of 4.25 years of follow-up, 6,611 (2.94%) MI cases were observed. After adjusting for confounders, new exercisers and exercise maintainers were significantly associated with a lower risk of incident MI than persistent non-exercisers (aHR, 0.849; 95% CI, 0.792-0.911; P-value < 0.001; and aHR, 0.746; 95% CI, 0.696-0.801; P-value < 0.001, respectively). Effects were consistent across sexes, more pronounced in those > 65 years. Notably, any level of physical activity after stroke was associated with a reduced MI risk compared to no exercise. CONCLUSIONS: In this nationwide cohort study, commencing or sustaining physical activity after an IS corresponded to a diminished likelihood of subsequent MI development. Advocating physical activity in ambulatory stroke survivors could potentially attenuate the prospective risk of MI.


Assuntos
Exercício Físico , AVC Isquêmico , Infarto do Miocárdio , Humanos , Masculino , Feminino , Infarto do Miocárdio/epidemiologia , República da Coreia/epidemiologia , Pessoa de Meia-Idade , AVC Isquêmico/epidemiologia , Idoso , Incidência , Adulto , Fatores de Risco
20.
Mar Drugs ; 22(6)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38921577

RESUMO

Sortase A (SrtA) is a cysteine transpeptidase that binds to the periplasmic membrane and plays a crucial role in attaching surface proteins, including staphylococcal protein A (SpA), to the peptidoglycan cell wall. Six pentacyclic polyketides (1-6) were isolated from the marine sponge Xestospongia sp., and their structures were elucidated using spectroscopic techniques and by comparing them to previously reported data. Among them, halenaquinol (2) was found to be the most potent SrtA inhibitor, with an IC50 of 13.94 µM (4.66 µg/mL). Semi-quantitative reverse transcription PCR data suggest that halenaquinol does not inhibit the transcription of srtA and spA, while Western blot analysis and immunofluorescence microscopy images suggest that it blocks the cell wall surface anchoring of SpA by inhibiting the activity of SrtA. The onset and magnitude of the inhibition of SpA anchoring on the cell wall surface in S. aureus that has been treated with halenaquinol at a value 8× that of the IC50 of SrtA are comparable to those for an srtA-deletion mutant. These findings contribute to the understanding of the mechanism by which marine-derived pentacyclic polyketides inhibit SrtA, highlighting their potential as anti-infective agents targeting S. aureus virulence.


Assuntos
Aminoaciltransferases , Antibacterianos , Proteínas de Bactérias , Parede Celular , Cisteína Endopeptidases , Poríferos , Staphylococcus aureus , Aminoaciltransferases/antagonistas & inibidores , Aminoaciltransferases/metabolismo , Cisteína Endopeptidases/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/antagonistas & inibidores , Animais , Poríferos/microbiologia , Antibacterianos/farmacologia , Antibacterianos/química , Policetídeos/farmacologia , Policetídeos/química
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