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1.
Cell ; 182(1): 226-244.e17, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32649875

RESUMO

Lung cancer in East Asia is characterized by a high percentage of never-smokers, early onset and predominant EGFR mutations. To illuminate the molecular phenotype of this demographically distinct disease, we performed a deep comprehensive proteogenomic study on a prospectively collected cohort in Taiwan, representing early stage, predominantly female, non-smoking lung adenocarcinoma. Integrated genomic, proteomic, and phosphoproteomic analysis delineated the demographically distinct molecular attributes and hallmarks of tumor progression. Mutational signature analysis revealed age- and gender-related mutagenesis mechanisms, characterized by high prevalence of APOBEC mutational signature in younger females and over-representation of environmental carcinogen-like mutational signatures in older females. A proteomics-informed classification distinguished the clinical characteristics of early stage patients with EGFR mutations. Furthermore, integrated protein network analysis revealed the cellular remodeling underpinning clinical trajectories and nominated candidate biomarkers for patient stratification and therapeutic intervention. This multi-omic molecular architecture may help develop strategies for management of early stage never-smoker lung adenocarcinoma.


Assuntos
Progressão da Doença , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteogenômica , Fumar/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinógenos/toxicidade , Estudos de Coortes , Citosina Desaminase/metabolismo , Ásia Oriental , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Genoma Humano , Humanos , Metaloproteinases da Matriz/metabolismo , Mutação/genética , Análise de Componente Principal
2.
Cell ; 179(6): 1409-1423.e17, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31778655

RESUMO

The evolution of flight in feathered dinosaurs and early birds over millions of years required flight feathers whose architecture features hierarchical branches. While barb-based feather forms were investigated, feather shafts and vanes are understudied. Here, we take a multi-disciplinary approach to study their molecular control and bio-architectural organizations. In rachidial ridges, epidermal progenitors generate cortex and medullary keratinocytes, guided by Bmp and transforming growth factor ß (TGF-ß) signaling that convert rachides into adaptable bilayer composite beams. In barb ridges, epidermal progenitors generate cylindrical, plate-, or hooklet-shaped barbule cells that form fluffy branches or pennaceous vanes, mediated by asymmetric cell junction and keratin expression. Transcriptome analyses and functional studies show anterior-posterior Wnt2b signaling within the dermal papilla controls barbule cell fates with spatiotemporal collinearity. Quantitative bio-physical analyses of feathers from birds with different flight characteristics and feathers in Burmese amber reveal how multi-dimensional functionality can be achieved and may inspire future composite material designs. VIDEO ABSTRACT.


Assuntos
Adaptação Fisiológica , Plumas/anatomia & histologia , Plumas/fisiologia , Voo Animal/fisiologia , Animais , Evolução Biológica , Aves/anatomia & histologia , Moléculas de Adesão Celular/metabolismo , Citoesqueleto/metabolismo , Derme/anatomia & histologia , Células-Tronco/citologia , Fatores de Tempo , Transcriptoma/genética , Via de Sinalização Wnt/genética
3.
Annu Rev Biochem ; 82: 497-530, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23746261

RESUMO

Isoprenoids are a class of natural products with more than 55,000 members. All isoprenoids are constructed from two precursors, isopentenyl diphosphate and its isomer dimethylallyl diphosphate. Two of the most important discoveries in isoprenoid biosynthetic studies in recent years are the elucidation of a second isoprenoid biosynthetic pathway [the methylerythritol phosphate (MEP) pathway] and a modified mevalonic acid (MVA) pathway. In this review, we summarize mechanistic insights on the MEP pathway enzymes. Because many isoprenoids have important biological activities, the need to produce them in sufficient quantities for downstream research efforts or commercial application is apparent. Recent advances in both MVA and MEP pathway-based synthetic biology are also illustrated by reviewing the landmark work of artemisinic acid and taxadien-5α-ol production through microbial fermentations.


Assuntos
Vias Biossintéticas/fisiologia , Eritritol/metabolismo , Hemiterpenos/biossíntese , Terpenos/metabolismo , Catálise , Humanos , Compostos Organofosforados
4.
Proc Natl Acad Sci U S A ; 121(4): e2314396121, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38236736

RESUMO

In our quest to leverage the capabilities of the emerging single-atom catalysts (SACs) for wastewater purification, we confronted fundamental challenges related to electron scarcity and instability. Through meticulous theoretical calculations, we identified optimal placements for nitrogen vacancies (Nv) and iron (Fe) single-atom sites, uncovering a dual-site approach that significantly amplified visible-light absorption and charge transfer dynamics. Informed by these computational insights, we cleverly integrated Nv into the catalyst design to boost electron density around iron atoms, yielding a potent and flexible photoactivator for benign peracetic acid. This exceptional catalyst exhibited remarkable stability and effectively degraded various organic contaminants over 20 cycles with self-cleaning properties. Specifically, the Nv sites captured electrons, enabling their swift transfer to adjacent Fe sites under visible light irradiation. This mechanism accelerated the reduction of the formed "peracetic acid-catalyst" intermediate. Theoretical calculations were used to elucidate the synergistic interplay of dual mechanisms, illuminating increased adsorption and activation of reactive molecules. Furthermore, electron reduction pathways on the conduction band were elaborately explored, unveiling the production of reactive species that enhanced photocatalytic processes. A six-flux model and associated parameters were also applied to precisely optimize the photocatalytic process, providing invaluable insights for future photocatalyst design. Overall, this study offers a molecule-level insight into the rational design of robust SACs in a photo-Fenton-like system, with promising implications for wastewater treatment and other high-value applications.

5.
N Engl J Med ; 388(8): 683-693, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36812432

RESUMO

BACKGROUND: Unilateral focused ultrasound ablation of the internal segment of globus pallidus has reduced motor symptoms of Parkinson's disease in open-label studies. METHODS: We randomly assigned, in a 3:1 ratio, patients with Parkinson's disease and dyskinesias or motor fluctuations and motor impairment in the off-medication state to undergo either focused ultrasound ablation opposite the most symptomatic side of the body or a sham procedure. The primary outcome was a response at 3 months, defined as a decrease of at least 3 points from baseline either in the score on the Movement Disorders Society-Unified Parkinson's Disease Rating Scale, part III (MDS-UPDRS III), for the treated side in the off-medication state or in the score on the Unified Dyskinesia Rating Scale (UDysRS) in the on-medication state. Secondary outcomes included changes from baseline to month 3 in the scores on various parts of the MDS-UPDRS. After the 3-month blinded phase, an open-label phase lasted until 12 months. RESULTS: Of 94 patients, 69 were assigned to undergo ultrasound ablation (active treatment) and 25 to undergo the sham procedure (control); 65 patients and 22 patients, respectively, completed the primary-outcome assessment. In the active-treatment group, 45 patients (69%) had a response, as compared with 7 (32%) in the control group (difference, 37 percentage points; 95% confidence interval, 15 to 60; P = 0.003). Of the patients in the active-treatment group who had a response, 19 met the MDS-UPDRS III criterion only, 8 met the UDysRS criterion only, and 18 met both criteria. Results for secondary outcomes were generally in the same direction as those for the primary outcome. Of the 39 patients in the active-treatment group who had had a response at 3 months and who were assessed at 12 months, 30 continued to have a response. Pallidotomy-related adverse events in the active-treatment group included dysarthria, gait disturbance, loss of taste, visual disturbance, and facial weakness. CONCLUSIONS: Unilateral pallidal ultrasound ablation resulted in a higher percentage of patients who had improved motor function or reduced dyskinesia than a sham procedure over a period of 3 months but was associated with adverse events. Longer and larger trials are required to determine the effect and safety of this technique in persons with Parkinson's disease. (Funded by Insightec; ClinicalTrials.gov number, NCT03319485.).


Assuntos
Globo Pálido , Ablação por Ultrassom Focalizado de Alta Intensidade , Doença de Parkinson , Humanos , Discinesias/etiologia , Discinesias/cirurgia , Globo Pálido/cirurgia , Doença de Parkinson/complicações , Doença de Parkinson/cirurgia , Resultado do Tratamento
6.
Mol Cell ; 69(2): 279-291.e5, 2018 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-29351847

RESUMO

Sustained energy starvation leads to activation of AMP-activated protein kinase (AMPK), which coordinates energy status with numerous cellular processes including metabolism, protein synthesis, and autophagy. Here, we report that AMPK phosphorylates the histone methyltransferase EZH2 at T311 to disrupt the interaction between EZH2 and SUZ12, another core component of the polycomb repressive complex 2 (PRC2), leading to attenuated PRC2-dependent methylation of histone H3 at Lys27. As such, PRC2 target genes, many of which are known tumor suppressors, were upregulated upon T311-EZH2 phosphorylation, which suppressed tumor cell growth both in cell culture and mouse xenografts. Pathologically, immunohistochemical analyses uncovered a positive correlation between AMPK activity and pT311-EZH2, and higher pT311-EZH2 correlates with better survival in both ovarian and breast cancer patients. Our finding suggests that AMPK agonists might be promising sensitizers for EZH2-targeting cancer therapies.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Animais , Carcinogênese/genética , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/fisiologia , Epigênese Genética , Feminino , Histonas/metabolismo , Humanos , Camundongos , Proteínas de Neoplasias , Proteínas Nucleares/metabolismo , Oncogenes , Neoplasias Ovarianas/metabolismo , Fosforilação , Complexo Repressor Polycomb 2/metabolismo , Complexo Repressor Polycomb 2/fisiologia , Fatores de Transcrição , Regulação para Cima
7.
Mol Cell ; 71(4): 606-620.e7, 2018 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-30118680

RESUMO

Metformin has been reported to possess antitumor activity and maintain high cytotoxic T lymphocyte (CTL) immune surveillance. However, the functions and detailed mechanisms of metformin's role in cancer immunity are not fully understood. Here, we show that metformin increases CTL activity by reducing the stability and membrane localization of programmed death ligand-1 (PD-L1). Furthermore, we discover that AMP-activated protein kinase (AMPK) activated by metformin directly phosphorylates S195 of PD-L1. S195 phosphorylation induces abnormal PD-L1 glycosylation, resulting in its ER accumulation and ER-associated protein degradation (ERAD). Consistently, tumor tissues from metformin-treated breast cancer patients exhibit reduced PD-L1 levels with AMPK activation. Blocking the inhibitory signal of PD-L1 by metformin enhances CTL activity against cancer cells. Our findings identify a new regulatory mechanism of PD-L1 expression through the ERAD pathway and suggest that the metformin-CTLA4 blockade combination has the potential to increase the efficacy of immunotherapy.


Assuntos
Antineoplásicos/farmacologia , Antígeno B7-H1/genética , Antígeno CTLA-4/genética , Regulação Neoplásica da Expressão Gênica , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/imunologia , Animais , Antígeno B7-H1/imunologia , Antígeno CTLA-4/imunologia , Linhagem Celular Tumoral , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Degradação Associada com o Retículo Endoplasmático , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/imunologia , Feminino , Glicosilação , Humanos , Glândulas Mamárias Humanas/citologia , Glândulas Mamárias Humanas/efeitos dos fármacos , Glândulas Mamárias Humanas/imunologia , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/genética , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos NOD , Fosforilação , Serina/metabolismo , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia
8.
Nucleic Acids Res ; 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39119895

RESUMO

High-quality primer design is essential for the success of all polymerase chain reaction (PCR)-based experiments. We previously developed a thermodynamics-based gene-specific quantitative PCR (qPCR) primer database for 147 organisms, which has been used extensively in gene expression studies. However, the number of organisms and the imperfection of function in the database limits its potential applications. Here, we improved the functionality of qPrimerDB to create a more comprehensive primer resource. Specifically, we (i) developed an improved primer design tool, qPrimer, building upon the previous qPrimerDB pipeline, to enhance the efficiency and simplicity of genome-scale qPCR primer design; (ii) pre-computed qPCR primer resources from 1 308 genomes of 1172 organisms and (iii) introduced a complete system for identifying, designing, checking, marking, and submitting qPCR primers. qPrimerDB 2.0 is freely available at https://qprimerdb.biodb.org. The qPrimer source code is available at https://github.com/swu1019lab/qPrimer.

9.
Plant Physiol ; 195(3): 1925-1940, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38427921

RESUMO

Leaf senescence is a vital aspect of plant physiology and stress responses and is induced by endogenous factors and environmental cues. The plant-specific NAC (NAM, ATAF1/2, CUC2) transcription factor family influences growth, development, and stress responses in Arabidopsis (Arabidopsis thaliana) and other species. However, the roles of NACs in tobacco (Nicotiana tabacum) leaf senescence are still unclear. Here, we report that NtNAC56 regulates leaf senescence in tobacco. Transgenic plants overexpressing NtNAC56 (NtNAC56-OE) showed induction of senescence-related genes and exhibited early senescence and lower chlorophyll content compared to wild-type (WT) plants and the Ntnac56-19 mutant. In addition, root development and seed germination were inhibited in the NtNAC56-OE lines. Transmission electron microscopy observations accompanied by physiological and biochemical assays revealed that NtNAC56 overexpression triggers chloroplast degradation and reactive oxygen species accumulation in tobacco leaves. Transcriptome analysis demonstrated that NtNAC56 activates leaf senescence-related genes and jasmonic acid (JA) biosynthesis pathway genes. In addition, the JA content of NtNAC56-OE plants was higher than in WT plants, and JA treatment induced NtNAC56 expression. We performed DNA affinity purification sequencing to identify direct targets of NtNAC56, among which we focused on LIPOXYGENASE 5 (NtLOX5), a key gene in JA biosynthesis. A dual-luciferase reporter assay and a yeast one-hybrid assay confirmed that NtNAC56 directly binds to the TTTCTT motif in the NtLOX5 promoter. Our results reveal a mechanism whereby NtNAC56 regulates JA-induced leaf senescence in tobacco and provide a strategy for genetically manipulating leaf senescence and plant growth.


Assuntos
Ciclopentanos , Regulação da Expressão Gênica de Plantas , Nicotiana , Oxilipinas , Folhas de Planta , Proteínas de Plantas , Senescência Vegetal , Plantas Geneticamente Modificadas , Fatores de Transcrição , Nicotiana/genética , Nicotiana/fisiologia , Nicotiana/efeitos dos fármacos , Nicotiana/crescimento & desenvolvimento , Oxilipinas/metabolismo , Oxilipinas/farmacologia , Ciclopentanos/metabolismo , Ciclopentanos/farmacologia , Folhas de Planta/metabolismo , Folhas de Planta/genética , Folhas de Planta/fisiologia , Senescência Vegetal/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Espécies Reativas de Oxigênio/metabolismo , Clorofila/metabolismo , Cloroplastos/metabolismo , Cloroplastos/ultraestrutura , Regiões Promotoras Genéticas/genética
10.
Nucleic Acids Res ; 51(9): 4223-4236, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-36484109

RESUMO

Rpc31 is a subunit in the TFIIE-related Rpc82/34/31 heterotrimeric subcomplex of Saccharomyces cerevisiae RNA polymerase III (pol III). Structural analyses of pol III have indicated that the N-terminal region of Rpc31 anchors on Rpc82 and further interacts with the polymerase core and stalk subcomplex. However, structural and functional information for the C-terminal region of Rpc31 is sparse. We conducted a mutational analysis on Rpc31, which uncovered a functional peptide adjacent to the highly conserved Asp-Glu-rich acidic C-terminus. This C-terminal peptide region, termed 'pre-acidic', is important for optimal cell growth, tRNA synthesis, and stable association of Rpc31 in the pre-initiation complex (PIC). Our site-directed photo-cross-linking to map protein interactions within the PIC reveal that this pre-acidic region specifically targets Rpc34 during transcription initiation, but also interacts with the DNA entry surface in free pol III. Thus, we have uncovered a switchable Rpc31 C-terminal region that functions in an initiation-specific protein interaction for pol III transcription.


Assuntos
RNA Polimerase III , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Iniciação da Transcrição Genética , Ligação Proteica , Domínios Proteicos , RNA Polimerase III/química , RNA Polimerase III/metabolismo , RNA de Transferência/biossíntese , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
11.
PLoS Genet ; 18(1): e1009952, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35051171

RESUMO

Overweight and obese are risk factors for various diseases. In Taiwan, the combined prevalence of overweight and obesity has increased dramatically. Here, we conducted a genome-wide association study (GWAS) on four adiposity traits, including body-mass index (BMI), body fat percentage (BF%), waist circumference (WC), and waist-hip ratio (WHR), using the data for more than 21,000 subjects in Taiwan Biobank. Associations were evaluated between 6,546,460 single-nucleotide polymorphisms (SNPs) and adiposity traits, yielding 13 genome-wide significant (GWS) adiposity-associated trait-loci pairs. A known gene, FTO, as well as two BF%-associated loci (GNPDA2-GABRG1 [4p12] and RNU6-2-PIAS1 [15q23]) were identified as pleiotropic effects. Moreover, RALGAPA1 was found as a specific genetic predisposing factor to high BMI in a Taiwanese population. Compared to other populations, a slightly lower heritability of the four adiposity traits was found in our cohort. Surprisingly, we uncovered the importance of neural pathways that might influence BF%, WC and WHR in the Taiwanese (East Asian) population. Additionally, a moderate genetic correlation between the WHR and BMI (γg = 0.52; p = 2.37×10-9) was detected, suggesting different genetic determinants exist for abdominal adiposity and overall adiposity. In conclusion, the obesity-related genetic loci identified here provide new insights into the genetic underpinnings of adiposity in the Taiwanese population.


Assuntos
Adiposidade/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Adulto , Bancos de Espécimes Biológicos , Estudos de Coortes , Feminino , Proteínas Ativadoras de GTPase/genética , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Obesidade/genética , Sobrepeso/genética , Polimorfismo de Nucleotídeo Único , Taiwan
12.
Proc Natl Acad Sci U S A ; 119(39): e2210908119, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36122239

RESUMO

Chlamydia protein associating with death domains (CADD) is involved in the biosynthesis of para-aminobenzoate (pABA), an essential component of the folate cofactor that is required for the survival and proliferation of the human pathogen Chlamydia trachomatis. The pathway used by Chlamydiae for pABA synthesis differs from the canonical multi-enzyme pathway used by most bacteria that relies on chorismate as a metabolic precursor. Rather, recent work showed pABA formation by CADD derives from l-tyrosine. As a member of the emerging superfamily of heme oxygenase-like diiron oxidases (HDOs), CADD was proposed to use a diiron cofactor for catalysis. However, we report maximal pABA formation by CADD occurs upon the addition of both iron and manganese, which implicates a heterobimetallic Fe:Mn cluster is the catalytically active form. Isotopic labeling experiments and proteomics studies show that CADD generates pABA from a protein-derived tyrosine (Tyr27), a residue that is ∼14 Šfrom the dimetal site. We propose that this self-sacrificial reaction occurs through O2 activation by a probable Fe:Mn cluster through a radical relay mechanism that connects to the "substrate" Tyr, followed by amination and direct oxygen insertion. These results provide the molecular basis for pABA formation in C. trachomatis, which will inform the design of novel therapeutics.


Assuntos
Proteínas de Bactérias , Chlamydia trachomatis , Oxigenases , Tirosina , para-Aminobenzoatos , Proteínas de Bactérias/metabolismo , Chlamydia trachomatis/enzimologia , Ácido Fólico , Ferro/metabolismo , Manganês/metabolismo , Oxigênio/metabolismo , Oxigenases/metabolismo , Tirosina/metabolismo , para-Aminobenzoatos/metabolismo
13.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34969844

RESUMO

Deoxypodophyllotoxin contains a core of four fused rings (A to D) with three consecutive chiral centers, the last being created by the attachment of a peripheral trimethoxyphenyl ring (E) to ring C. Previous studies have suggested that the iron(II)- and 2-oxoglutarate-dependent (Fe/2OG) oxygenase, deoxypodophyllotoxin synthase (DPS), catalyzes the oxidative coupling of ring B and ring E to form ring C and complete the tetracyclic core. Despite recent efforts to deploy DPS in the preparation of deoxypodophyllotoxin analogs, the mechanism underlying the regio- and stereoselectivity of this cyclization event has not been elucidated. Herein, we report 1) two structures of DPS in complex with 2OG and (±)-yatein, 2) in vitro analysis of enzymatic reactivity with substrate analogs, and 3) model reactions addressing DPS's catalytic mechanism. The results disfavor a prior proposal of on-pathway benzylic hydroxylation. Rather, the DPS-catalyzed cyclization likely proceeds by hydrogen atom abstraction from C7', oxidation of the benzylic radical to a carbocation, Friedel-Crafts-like ring closure, and rearomatization of ring B by C6 deprotonation. This mechanism adds to the known pathways for transformation of the carbon-centered radical in Fe/2OG enzymes and suggests what types of substrate modification are likely tolerable in DPS-catalyzed production of deoxypodophyllotoxin analogs.


Assuntos
Berberidaceae/enzimologia , Medicamentos de Ervas Chinesas/química , Ligases/química , Proteínas de Plantas/química , Podofilotoxina/análogos & derivados , Oxirredução , Podofilotoxina/química
14.
Circulation ; 148(24): e187-e280, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-37942682

RESUMO

The International Liaison Committee on Resuscitation engages in a continuous review of new, peer-reviewed, published cardiopulmonary resuscitation and first aid science. Draft Consensus on Science With Treatment Recommendations are posted online throughout the year, and this annual summary provides more concise versions of the final Consensus on Science With Treatment Recommendations from all task forces for the year. Topics addressed by systematic reviews this year include resuscitation of cardiac arrest from drowning, extracorporeal cardiopulmonary resuscitation for adults and children, calcium during cardiac arrest, double sequential defibrillation, neuroprognostication after cardiac arrest for adults and children, maintaining normal temperature after preterm birth, heart rate monitoring methods for diagnostics in neonates, detection of exhaled carbon dioxide in neonates, family presence during resuscitation of adults, and a stepwise approach to resuscitation skills training. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, using Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces list priority knowledge gaps for further research. Additional topics are addressed with scoping reviews and evidence updates.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Nascimento Prematuro , Adulto , Feminino , Criança , Recém-Nascido , Humanos , Primeiros Socorros , Consenso , Parada Cardíaca Extra-Hospitalar/diagnóstico , Parada Cardíaca Extra-Hospitalar/terapia
15.
Neuroimage ; 289: 120535, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38342188

RESUMO

Neurovascular coupling serves as an essential neurophysiological mechanism in functional neuroimaging, which is generally presumed to be robust and invariant across different physiological states, encompassing both task engagement and resting state. Nevertheless, emerging evidence suggests that neurovascular coupling may exhibit state dependency, even in normal human participants. To investigate this premise, we analyzed the cross-frequency spectral correspondence between concurrently recorded electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) data, utilizing them as proxies for neurovascular coupling during the two conditions: an eye-open-eye-close (EOEC) task and a resting state. We hypothesized that given the state dependency of neurovascular coupling, EEG-fMRI spectral correspondences would change between the two conditions in the visual system. During the EOEC task, we observed a negative phase-amplitude-coupling (PAC) between EEG alpha-band and fMRI visual activity. Conversely, in the resting state, a pronounced amplitude-amplitude-coupling (AAC) emerged between EEG and fMRI signals, as evidenced by the spectral correspondence between the EEG gamma-band of the midline occipital channel (Oz) and the high-frequency fMRI signals (0.15-0.25 Hz) in the visual network. This study reveals distinct scenarios of EEG-fMRI spectral correspondence in healthy participants, corroborating the state-dependent nature of neurovascular coupling.


Assuntos
Imageamento por Ressonância Magnética , Acoplamento Neurovascular , Humanos , Imageamento por Ressonância Magnética/métodos , Acoplamento Neurovascular/fisiologia , Mapeamento Encefálico/métodos , Eletroencefalografia/métodos , Olho , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia
16.
J Am Chem Soc ; 146(35): 24271-24287, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39172701

RESUMO

Hyoscyamine 6ß-hydroxylase (H6H) is an iron(II)- and 2-oxoglutarate-dependent (Fe/2OG) oxygenase that produces the prolifically administered antinausea drug, scopolamine. After its namesake hydroxylation reaction, H6H then couples the newly installed C6 oxygen to C7 to produce the drug's epoxide functionality. Oxoiron(IV) (ferryl) intermediates initiate both reactions by cleaving C-H bonds, but it remains unclear how the enzyme switches the target site and promotes (C6)O-C7 coupling in preference to C7 hydroxylation in the second step. In one possible epoxidation mechanism, the C6 oxygen would─analogously to mechanisms proposed for the Fe/2OG halogenases and, in our more recent study, N-acetylnorloline synthase (LolO)─coordinate as alkoxide to the C7-H-cleaving ferryl intermediate to enable alkoxyl coupling to the ensuing C7 radical. Here, we provide structural and kinetic evidence that H6H does not employ substrate coordination or repositioning for the epoxidation step but instead exploits the distinct spatial dependencies of competitive C-H cleavage (C6 vs C7) and C-O-coupling (oxygen rebound vs cyclization) steps to promote the two-step sequence. Structural comparisons of ferryl-mimicking vanadyl complexes of wild-type H6H and a variant that preferentially 7-hydroxylates instead of epoxidizing 6ß-hydroxyhyoscyamine suggest that a modest (∼10°) shift in the Fe-O-H(C7) approach angle is sufficient to change the outcome. The 7-hydroxylation:epoxidation partition ratios of both proteins increase more than 5-fold in 2H2O, reflecting an epoxidation-specific requirement for cleavage of the alcohol O-H bond, which, unlike in the LolO oxacyclization, is not accomplished by iron coordination in advance of C-H cleavage.


Assuntos
Oxigenases de Função Mista , Hidroxilação , Oxigenases de Função Mista/metabolismo , Oxigenases de Função Mista/química , Especificidade por Substrato , Biocatálise , Compostos de Epóxi/química , Compostos de Epóxi/metabolismo
17.
Eur J Neurosci ; 60(3): 4182-4200, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38779808

RESUMO

Peak alpha frequency (PAF), the dominant oscillatory frequency within the alpha range (8-12 Hz), is associated with cognitive function and several neurological conditions, including chronic pain. Manipulating PAF could offer valuable insight into the relationship between PAF and various functions and conditions, potentially providing new treatment avenues. This systematic review aimed to comprehensively synthesise effects of non-invasive brain stimulation (NIBS) on PAF speed. Relevant studies assessing PAF pre- and post-NIBS in healthy adults were identified through systematic searches of electronic databases (Embase, PubMed, PsychINFO, Scopus, The Cochrane Library) and trial registers. The Cochrane risk-of-bias tool was employed for assessing study quality. Quantitative analysis was conducted through pairwise meta-analysis when possible; otherwise, qualitative synthesis was performed. The review protocol was registered with PROSPERO (CRD42020190512) and the Open Science Framework (https://osf.io/2yaxz/). Eleven NIBS studies were included, all with a low risk-of-bias, comprising seven transcranial alternating current stimulation (tACS), three repetitive transcranial magnetic stimulation (rTMS), and one transcranial direct current stimulation (tDCS) study. Meta-analysis of active tACS conditions (eight conditions from five studies) revealed no significant effects on PAF (mean difference [MD] = -0.12, 95% CI = -0.32 to 0.08, p = 0.24). Qualitative synthesis provided no evidence that tDCS altered PAF and moderate evidence for transient increases in PAF with 10 Hz rTMS. However, it is crucial to note that small sample sizes were used, there was substantial variation in stimulation protocols, and most studies did not specifically target PAF alteration. Further studies are needed to determine NIBS's potential for modulating PAF.


Assuntos
Ritmo alfa , Estimulação Transcraniana por Corrente Contínua , Estimulação Magnética Transcraniana , Humanos , Estimulação Transcraniana por Corrente Contínua/métodos , Estimulação Magnética Transcraniana/métodos , Ritmo alfa/fisiologia , Encéfalo/fisiologia
18.
Mol Med ; 30(1): 73, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822233

RESUMO

Human malignant pleural mesothelioma (hMPM) is an aggressive, rare disease with a poor prognosis. Histologically, MPM is categorized into epithelioid, biphasic, and sarcomatoid subtypes, with the epithelioid subtype generally displaying a better response to treatment. Conversely, effective therapies for the non-epithelioid subtypes are limited. This study aimed to investigate the potential role of FK228, a histone deacetylase inhibitor, in the suppression of hMPM tumor growth. We conducted a comprehensive analysis of the histological and molecular characteristics of two MPM cell lines, CRL-5820 (epithelioid) and CRL-5946 (non-epithelioid). CRL-5946 cells and non-epithelioid patient-derived xenografted mice exhibited heightened growth rates compared to those with epithelioid MPM. Both CRL-5946 cells and non-epithelioid mice displayed a poor response to cisplatin. However, FK228 markedly inhibited the growth of both epithelioid and non-epithelioid tumor cells in vitro and in vivo. Cell cycle analysis revealed FK228-induced G1/S and mitotic arrest in MPM cells. Caspase inhibitor experiments demonstrated that FK228-triggered apoptosis occurred via a caspase-dependent pathway in CRL-5946 but not in CRL-5820 cells. Additionally, a cytokine array analysis showed that FK228 reduced the release of growth factors, including platelet-derived and vascular endothelial growth factors, specifically in CRL-5946 cells. These results indicate that FK228 exhibits therapeutic potential in MPM by inducing cytotoxicity and modulating the tumor microenvironment, potentially benefiting both epithelioid and non-epithelioid subtypes.


Assuntos
Apoptose , Proliferação de Células , Depsipeptídeos , Mesotelioma Maligno , Mesotelioma , Ensaios Antitumorais Modelo de Xenoenxerto , Humanos , Animais , Mesotelioma Maligno/tratamento farmacológico , Mesotelioma Maligno/patologia , Linhagem Celular Tumoral , Camundongos , Mesotelioma/tratamento farmacológico , Mesotelioma/patologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Depsipeptídeos/farmacologia , Depsipeptídeos/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pleurais/tratamento farmacológico , Neoplasias Pleurais/patologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Feminino , Células Epitelioides/patologia , Ciclo Celular/efeitos dos fármacos
19.
Oncologist ; 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39245044

RESUMO

BACKGROUND: The impact of sidedness on survival of later-line treatment in patients with metastatic colorectal cancer (mCRC) is undetermined. This study aimed to investigate the association between sidedness and survival among chemotherapy refractory patients with mCRC treated with trifluridine/tipiracil (TAS-102) or regorafenib or both. PATIENTS AND METHODS: Patients with mCRC treated with TAS-102 or regorafenib between 2015 and 2020 was retrospectively collected. Patients were stratified into TAS-102 first and regorafenib first, then subdivided into TAS-102 followed by regorafenib (T-R) and regorafenib followed by TAS-102 (R-T) groups. The oncologic outcomes were presented with time-to-treatment failure (TTF) and overall survival (OS). RESULTS: After matching, 376 TAS-102 patients and 376 regorafenib patients were included for outcomes comparison. TTF had insignificant differences while OS was significantly different between TAS-102 and regorafenib groups. Median TTF and OS were 1.9 months versus 2.0 months (P = .701) and 9.1 months versus 7.0 months (P = .008) in TAS-102 and regorafenib, respectively. The OS benefits were consistent regardless primary tumor location. Subgroup analysis with 174 T-R patients and 174 R-T patients was investigated for treatment sequences. TTF and OS had significant differences in both groups. Median TTF and OS were 8.5 months versus 6.3 months (P = .001) and 14.4 months versus 12.6 months (P = .035) in T-R and R-T groups, respectively. The TTF and OS benefits were persisted regardless primary tumor location. CONCLUSION: TAS-102 first provided a better survival benefit in chemotherapy refractory patients with mCRC across all sidedness. Further prospective studies are warranted to validate our conclusions.

20.
Artigo em Inglês | MEDLINE | ID: mdl-39251170

RESUMO

BACKGROUND AND AIMS: Early-onset colorectal cancer (CRC) is increasing globally. While the United States have lowered the age of initiation of screening to 45, other countries still start screening at age 50. In Taiwan, the incidence of CRC has declined in 55-74 year-olds after the initiation of screening, but still increased in those 50-54, potentially due to rising precancerous lesion incidence in 40-49 year-olds. This study aimed to explore the chronological trend of the prevalence of colorectal advanced neoplasms (AN) in the screening population aged 40-54. METHODS: We retrospectively analyzed a screening colonoscopy cohort for prevalence of AN in average-risk subjects aged 40-54 from 2003 to 2019. Logistic regression was used to distinguish cohort effect from time-period effect on the prevalence of AN. RESULTS: In total, 27,805 subjects (52.1% male) men were enrolled. There were notable increases in prevalence of AN in all three age groups during the 17-year span, but these were more rapid in age 40-44 (0.99% to 3.22%) and 45-49 (2.50% to 4.19%). Age 50-54 had higher risk of AN [aOR=1.62(1.19-2.19)] in 2003-2008 but not in later periods [2009-2014: aOR=1.08(0.83-1.41)] and [2015-2019: aOR=0.76(0.56-1.03)] when compared with age 45-49. CONCLUSION: The prevalence of AN in age 40-54 increased in the Taiwanese population, with a later birth cohort having a higher prevalence of AN. However, the prevalence of AN in age 45-49 increased more remarkably and approximated that in age 50-54, which may justify earlier initiation of CRC screening at age 45.

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