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1.
Cell ; 182(1): 226-244.e17, 2020 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-32649875

RESUMEN

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.


Asunto(s)
Progresión de la Enfermedad , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Proteogenómica , Fumar/genética , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinógenos/toxicidad , Estudios de Cohortes , Citosina Desaminasa/metabolismo , Asia Oriental , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Genoma Humano , Humanos , Metaloproteinasas de la Matriz/metabolismo , Mutación/genética , Análisis de Componente Principal
2.
Mol Cell Proteomics ; 23(5): 100762, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38608839

RESUMEN

Protein post-translational modifications (PTMs) are crucial in plant cellular processes, particularly in protein folding and signal transduction. N-glycosylation and phosphorylation are notably significant PTMs, playing essential roles in regulating plant responses to environmental stimuli. However, current sequential enrichment methods for simultaneous analysis of phosphoproteome and N-glycoproteome are labor-intensive and time-consuming, limiting their throughput. Addressing this challenge, this study introduces a novel tandem S-Trap-IMAC-HILIC (S-Trap: suspension trapping; IMAC: immobilized metal ion affinity chromatography; HILIC: hydrophilic interaction chromatography) strategy, termed TIMAHAC, for simultaneous analysis of plant phosphoproteomics and N-glycoproteomics. This approach integrates IMAC and HILIC into a tandem tip format, streamlining the enrichment process of phosphopeptides and N-glycopeptides. The key innovation lies in the use of a unified buffer system and an optimized enrichment sequence to enhance efficiency and reproducibility. The applicability of TIMAHAC was demonstrated by analyzing the Arabidopsis phosphoproteome and N-glycoproteome in response to abscisic acid (ABA) treatment. Up to 1954 N-glycopeptides and 11,255 phosphopeptides were identified from Arabidopsis, indicating its scalability for plant tissues. Notably, distinct perturbation patterns were observed in the phosphoproteome and N-glycoproteome, suggesting their unique contributions to ABA response. Our results reveal that TIMAHAC offers a comprehensive approach to studying complex regulatory mechanisms and PTM interplay in plant biology, paving the way for in-depth investigations into plant signaling networks.


Asunto(s)
Arabidopsis , Cromatografía de Afinidad , Fosfoproteínas , Proteómica , Flujo de Trabajo , Proteómica/métodos , Arabidopsis/metabolismo , Fosfoproteínas/metabolismo , Fosfoproteínas/análisis , Cromatografía de Afinidad/métodos , Proteínas de Arabidopsis/metabolismo , Glicopéptidos/metabolismo , Glicopéptidos/análisis , Interacciones Hidrofóbicas e Hidrofílicas , Procesamiento Proteico-Postraduccional , Proteoma/metabolismo , Fosforilación , Fosfopéptidos/metabolismo , Fosfopéptidos/análisis , Espectrometría de Masas en Tándem , Proteínas de Plantas/metabolismo
3.
Mol Cell Proteomics ; : 100804, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38901673

RESUMEN

Osmotic stress significantly hampers plant growth and crop yields, emphasizing the need for a thorough comprehension of the underlying molecular responses. Previous research has demonstrated that osmotic stress rapidly induces calcium influx and signaling, along with the activation of a specific subset of protein kinases, notably the Raf-SnRK2 kinase cascades within minutes. However, the intricate interplay between calcium signaling and the activation of RAF-SnRK2 kinase cascades remains elusive. Here in this study, we discovered that Raf-like protein (RAF) kinases undergo hyperphosphorylation in response to osmotic shocks. Intriguingly, treatment with the calcium chelator EGTA robustly activates RAF-SnRK2 cascades, mirroring the effects of osmotic treatment. Utilizing high-throughput DIA-based phosphoproteomics, we unveiled the global impact of EGTA on protein phosphorylation. Beyond the activation of RAFs and sucrose non-fermenting-1-related protein kinase 2s (SnRK2s), EGTA treatment also activates mitogen-activated protein kinase (MAPKs) cascades, Calcium-dependent protein kinases (CDPKs), and receptor-like protein kinases, etc. Through overlapping assays, we identified potential roles of mitogen-activated protein kinase kinase kinase kinases (MAP4Ks) and receptor-like protein kinases in the osmotic-stress-induced activation of RAF-SnRK2 cascades. Our findings illuminate the regulation of phosphorylation and cellular events by Ca2+ signaling, offering insights into the (exocellular) Ca2+ deprivation during early hyperosmolality sensing and signaling.

4.
Proc Natl Acad Sci U S A ; 120(13): e2300363120, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36961922

RESUMEN

α- and ß-neurexins are extensively alternatively spliced, presynaptic cell-adhesion molecules that are thought to organize synapse assembly. However, recent data revealed that, in the hippocampus in vivo, the deletion of one neurexin isoform, Nrxn2, surprisingly increased excitatory synapse numbers and enhanced their presynaptic release probability, suggesting that Nrxn2 restricts, instead of enabling, synapse assembly. To delineate the synaptic function and mechanism of action of Nrxn2, we examined cultured hippocampal neurons as a reduced system. In heterologous synapse formation assays, different alternatively spliced Nrxn2ß isoforms robustly promoted synapse assembly similar to Nrxn1ß and Nrxn3ß, consistent with a general synaptogenic function of neurexins. Deletion of Nrxn2 from cultured hippocampal neurons, however, caused a significant increase in synapse density and release probability, replicating the in vivo data that suggested a synapse-restricting function. Rescue experiments revealed that two of the four Nrxn2ß splice variants (Nrxn2ß-SS4+/SS5- and Nrxn2ß-SS4+/SS5+) reversed the increase in synapse density in Nrxn2-deficient neurons, whereas only one of the four Nrxn2ß splice variants (Nrxn2ß-SS4+/SS5+) normalized the increase in release probability in Nrxn2-deficient neurons. Thus, a subset of Nrxn2 splice variants restricts synapse numbers and restrains their release probability in cultured neurons.


Asunto(s)
Empalme Alternativo , Sinapsis , Sinapsis/metabolismo , Hipocampo/metabolismo , Moléculas de Adhesión Celular/metabolismo , Neuronas/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Moléculas de Adhesión de Célula Nerviosa/genética , Moléculas de Adhesión de Célula Nerviosa/metabolismo
5.
Mol Cell Proteomics ; 22(9): 100624, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37495186

RESUMEN

Secondary mutation, T790M, conferring tyrosine kinase inhibitors (TKIs) resistance beyond oncogenic epidermal growth factor receptor (EGFR) mutations presents a challenging unmet need. Although TKI-resistant mechanisms are intensively investigated, the underlying responses of cancer cells adapting drug perturbation are largely unknown. To illuminate the molecular basis linking acquired mutation to TKI resistance, affinity purification coupled mass spectrometry was adopted to dissect EGFR interactome in TKI-sensitive and TKI-resistant non-small cell lung cancer cells. The analysis revealed TKI-resistant EGFR-mutant interactome allocated in diverse subcellular distribution and enriched in endocytic trafficking, in which gefitinib intervention activated autophagy-mediated EGFR degradation and thus autophagy inhibition elevated gefitinib susceptibility. Alternatively, gefitinib prompted TKI-sensitive EGFR translocating toward cell periphery through Rab7 ubiquitination which may favor efficacy to TKIs suppression. This study revealed that T790M mutation rewired EGFR interactome that guided EGFR to autophagy-mediated degradation to escape treatment, suggesting that combination therapy with TKI and autophagy inhibitor may overcome acquired resistance in non-small cell lung cancer.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Gefitinib/farmacología , Receptores ErbB/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Mutación/genética , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Resistencia a Antineoplásicos/genética , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral
6.
Cereb Cortex ; 33(4): 1130-1139, 2023 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-35349640

RESUMEN

Mild isolated fetal ventriculomegaly (iFVM) is the most common abnormality of the fetal central nervous system. It is characterized by enlargement of one or both of the lateral ventricles (defined as ventricular width greater than 10 mm, but less than 12 mm). Despite its high prevalence, the pathophysiology of iFVM during fetal brain development and the neurobiological substrate beyond ventricular enlargement remain unexplored. In this work, we aimed to establish the relationships between the structural development of transient fetal brain zones/compartments and increased cerebrospinal fluid volume. For this purpose, we used in vivo structural T2-weighted magnetic resonance imaging of 89 fetuses (48 controls and 41 cases with iFVM). Our results indicate abnormal development of transient zones/compartments belonging to both hemispheres (i.e. on the side with and also on the contralateral side without a dilated ventricle) in fetuses with iFVM. Specifically, compared to controls, we observed enlargement of proliferative zones and overgrowth of the cortical plate in iFVM with associated reduction of volumes of central structures, subplate, and fetal white matter. These results indicate that enlarged lateral ventricles might be linked to the development of transient fetal zones and that global brain development should be taken into consideration when evaluating iFVM.


Asunto(s)
Hidrocefalia , Imagen por Resonancia Magnética , Embarazo , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Ultrasonografía Prenatal/métodos , Hidrocefalia/diagnóstico por imagen , Hidrocefalia/complicaciones , Hidrocefalia/patología , Encéfalo/patología , Feto
7.
BMC Med Inform Decis Mak ; 24(1): 77, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38500135

RESUMEN

OBJECTIVE: To address the challenge of assessing sedation status in critically ill patients in the intensive care unit (ICU), we aimed to develop a non-contact automatic classifier of agitation using artificial intelligence and deep learning. METHODS: We collected the video recordings of ICU patients and cut them into 30-second (30-s) and 2-second (2-s) segments. All of the segments were annotated with the status of agitation as "Attention" and "Non-attention". After transforming the video segments into movement quantification, we constructed the models of agitation classifiers with Threshold, Random Forest, and LSTM and evaluated their performances. RESULTS: The video recording segmentation yielded 427 30-s and 6405 2-s segments from 61 patients for model construction. The LSTM model achieved remarkable accuracy (ACC 0.92, AUC 0.91), outperforming other methods. CONCLUSION: Our study proposes an advanced monitoring system combining LSTM and image processing to ensure mild patient sedation in ICU care. LSTM proves to be the optimal choice for accurate monitoring. Future efforts should prioritize expanding data collection and enhancing system integration for practical application.


Asunto(s)
Aprendizaje Profundo , Agitación Psicomotora , Humanos , Agitación Psicomotora/diagnóstico , Inteligencia Artificial , Unidades de Cuidados Intensivos , Cuidados Críticos
8.
Int J Mol Sci ; 25(1)2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38203247

RESUMEN

MicroRNAs (miRNAs) can regulate the expression of genes involved in the establishment of the window of implantation (WOI) in the endometrium. Recent studies indicated that cell-free miRNAs in uterine fluid and blood samples could act as alternative and non-invasive sample types for endometrial receptivity analysis. In this study, we attempt to systematically evaluate whether the expression levels of cell-free microRNAs in blood samples could be used as non-invasive biomarkers for assessing endometrial receptivity status. We profiled the miRNA expression levels of 111 blood samples using next-generation sequencing to establish a predictive model for the assessment of endometrial receptivity status. This model was validated with an independent dataset (n = 73). The overall accuracy is 95.9%. Specifically, we achieved accuracies of 95.9%, 95.9%, and 100.0% for the pre-receptive group, the receptive group, and the post-respective group, respectively. Additionally, we identified a set of differentially expressed miRNAs between different endometrial receptivity statuses using the following criteria: p-value < 0.05 and fold change greater than 1.5 or less than -1.5. In conclusion, the expression levels of cell-free miRNAs in blood samples can be utilized in a non-invasive manner to distinguish different endometrial receptivity statuses.


Asunto(s)
MicroARN Circulante , MicroARNs , Femenino , Humanos , Implantación del Embrión/genética , Transferencia de Embrión , Endometrio , MicroARNs/genética
9.
J Neurosci ; 40(28): 5389-5401, 2020 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-32532887

RESUMEN

Spontaneous neurotransmitter release is a fundamental property of synapses in which neurotransmitter filled vesicles release their content independent of presynaptic action potentials (APs). Despite their seemingly random nature, these spontaneous fusion events can be regulated by Ca2+ signaling pathways. Here, we probed the mechanisms that maintain Ca2+ sensitivity of spontaneous release events in synapses formed between hippocampal neurons cultured from rats of both sexes. In this setting, we examined the potential role of vesicle-associated membrane protein 4 (VAMP4), a vesicular soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) protein in spontaneous neurotransmission. Our results show that VAMP4 is required for Ca2+-dependent spontaneous excitatory neurotransmission, with a limited role in spontaneous inhibitory neurotransmission. Key residues in VAMP4 that regulate its retrieval as well as functional clathrin-mediated vesicle trafficking were essential for the maintenance of VAMP4-mediated spontaneous release. Moreover, high-frequency stimulation (HFS) that typically triggers asynchronous release and retrieval of VAMP4 from the plasma membrane also augmentsCa2+-sensitive spontaneous release for up to 30 min in a VAMP4-dependent manner. This VAMP4-mediated link between asynchronous and spontaneous excitatory neurotransmission might serve as a presynaptic substrate for synaptic plasticity coupling distinct forms of release.SIGNIFICANCE STATEMENT Spontaneous neurotransmitter release that occurs independent of presynaptic action potentials (APs) shows significant sensitivity to intracellular Ca2+ levels. In this study, we identify the vesicular soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) molecule vesicle-associated membrane protein 4 (VAMP4) as a key component of the machinery that maintains these Ca2+-sensitive fraction of spontaneous release events. Following brief intense activity, VAMP4-dependent synaptic vesicle retrieval supports a pool of vesicles that fuse spontaneously in the long term. We propose that this vesicle trafficking pathway acts to shape spontaneous release and associated signaling based on previous activity history of synapses.


Asunto(s)
Calcio/metabolismo , Hipocampo/metabolismo , Neuronas/metabolismo , Proteínas R-SNARE/metabolismo , Vesículas Sinápticas/metabolismo , Potenciales de Acción/fisiología , Animales , Células Cultivadas , Femenino , Hipocampo/citología , Masculino , Ratones , Neuronas/citología , Técnicas de Placa-Clamp , Proteínas R-SNARE/genética , Ratas , Ratas Sprague-Dawley , Sinapsis/metabolismo , Transmisión Sináptica/fisiología
10.
J Virol ; 94(4)2020 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-31776277

RESUMEN

The strongest evidence of the oncogenicity of Epstein-Barr virus (EBV) in vitro is its ability to immortalize human primary B lymphocytes into lymphoblastoid cell lines (LCLs). Yet the underlying mechanisms explaining how the virus tempers the growth program of the host cells have not been fully elucidated. The mitogen-activated protein kinases (MAPKs) are implicated in many cellular processes and are constitutively activated in LCLs. We questioned the expression and regulation of the dual-specificity phosphatases (DUSPs), the main negative regulator of MAPKs, during EBV infection and immortalization. Thirteen DUSPs, including 10 typical and 3 atypical types of DUSPs, were tested. Most of them were downregulated after EBV infection. Here, a role of viral oncogene latent membrane protein 1 (LMP1) in limiting DUSP6 and DUSP8 expression was identified. Using MAPK inhibitors, we found that LMP1 activates extracellular signal-regulated kinase (ERK) or p38 to repress the expression of DUSP6 and DUSP8, with corresponding substrate specificity. Morphologically, overexpression of DUSP6 and DUSP8 attenuates the ability of EBV-immortalized LCL cells to clump together. Mechanistically, apoptosis induced by restoring DUSP6 and DUSP8 in LCLs indicated a novel mechanism for LMP1 to provide a survival signal during EBV immortalization. Collectively, this report provides the first description of the interplay between EBV genes and DUSPs and contributes considerably to the interpretation of MAPK regulation in EBV immortalization.IMPORTANCE Infections by the ubiquitous Epstein-Barr virus (EBV) are associated with a wide spectrum of lymphomas and carcinomas. It has been well documented that activation levels of MAPKs are found in cancer cells to translate various external or intrinsic stimuli into cellular responses. Physiologically, the dual-specificity phosphates (DUSPs) exhibit great ability in regulating MAPK activities with respect to their capability of dephosphorylating MAPKs. In this study, we found that DUSPs were generally downregulated after EBV infection. EBV oncogenic latent membrane protein 1 (LMP1) suppressed DUSP6 and DUSP8 expression via MAPK pathway. In this way, LMP1-mediated MAPK activation was a continuous process. Furthermore, DUSP downregulation was found to contribute greatly to prevent apoptosis of EBV-infected cells. To sum up, this report sheds light on a novel molecular mechanism explaining how EBV maintains the unlimited proliferation status of the immortalized cells and provides a new link to understand EBV-induced B cell survival.


Asunto(s)
Fosfatasas de Especificidad Dual/genética , Herpesvirus Humano 4/metabolismo , Proteínas de la Matriz Viral/metabolismo , Apoptosis/genética , Linfocitos B/virología , Línea Celular Tumoral , Fosfatasas de Especificidad Dual/metabolismo , Infecciones por Virus de Epstein-Barr/virología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Genes Virales/genética , Humanos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Cultivo Primario de Células , Proteínas de la Matriz Viral/fisiología , Proteínas Virales/metabolismo , Latencia del Virus/genética , Latencia del Virus/fisiología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
11.
Acta Pharmacol Sin ; 42(7): 1069-1079, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33758353

RESUMEN

Sepsis is life-threatening organ dysfunction due to dysregulated systemic inflammatory and immune response to infection, often leading to cognitive impairments. Growing evidence shows that artemisinin, an antimalarial drug, possesses potent anti-inflammatory and immunoregulatory activities. In this study we investigated whether artemisinin exerted protective effect against neurocognitive deficits associated with sepsis and explored the underlying mechanisms. Mice were injected with LPS (750 µg · kg-1 · d-1, ip, for 7 days) to establish an animal model of sepsis. Artemisinin (30 mg · kg-1 · d-1, ip) was administered starting 4 days prior LPS injection and lasting to the end of LPS injection. We showed that artemisinin administration significantly improved LPS-induced cognitive impairments assessed in Morris water maze and Y maze tests, attenuated neuronal damage and microglial activation in the hippocampus. In BV2 microglial cells treated with LPS (100 ng/mL), pre-application of artemisinin (40 µΜ) significantly reduced the production of proinflammatory cytokines (i.e., TNF-α, IL-6) and suppressed microglial migration. Furthermore, we revealed that artemisinin significantly suppressed the nuclear translocation of NF-κB and the expression of proinflammatory cytokines by activating the AMPKα1 pathway; knockdown of AMPKα1 markedly abolished the anti-inflammatory effects of artemisinin in BV2 microglial cells. In conclusion, atemisinin is a potential therapeutic agent for sepsis-associated neuroinflammation and cognitive impairment, and its effect is probably mediated by activation of the AMPKα1 signaling pathway in microglia.


Asunto(s)
Artemisininas/uso terapéutico , Microglía/efectos de los fármacos , Trastornos Neurocognitivos/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Sepsis/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Antiinflamatorios/uso terapéutico , Región CA1 Hipocampal/efectos de los fármacos , Región CA1 Hipocampal/patología , Muerte Celular/efectos de los fármacos , Línea Celular , Movimiento Celular/efectos de los fármacos , Citocinas/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/etiología , Inflamación/metabolismo , Lipopolisacáridos , Masculino , Ratones Endogámicos C57BL , Microglía/metabolismo , Prueba del Laberinto Acuático de Morris/efectos de los fármacos , Trastornos Neurocognitivos/etiología , Trastornos Neurocognitivos/metabolismo , Neuronas/efectos de los fármacos , Sepsis/inducido químicamente , Sepsis/complicaciones , Sepsis/metabolismo
12.
Cell Mol Neurobiol ; 40(7): 1231-1242, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32140899

RESUMEN

Recent studies demonstrated that FoxO3 circular RNA (circFoxO3) plays an important regulatory role in tumourigenesis and cardiomyopathy. However, the role of circFoxO3 in neurodegenerative diseases remains unknown. The aim of this study was to examine the possible role of circFoxO3 in neurodegenerative diseases and the underlying mechanisms. To model human neurodegenerative conditions, hippocampus-derived neurons were treated with glutamate. Using molecular and cellular biology approaches, we found that circFoxO3 expression was significantly higher in the glutamate treatment group than that in the control group. Furthermore, silencing of circFoxO3 protected HT22 cells from glutamate-induced oxidative injury through the inhibition of the mitochondrial apoptotic pathway. Collectively, our study demonstrates that endogenous circFoxO3 plays a key role in inducing apoptosis and neuronal cell death and may act as a novel therapeutic target for neurodegenerative diseases.


Asunto(s)
Apoptosis/efectos de los fármacos , Ácido Glutámico/farmacología , Hipocampo/metabolismo , Mitocondrias/metabolismo , ARN Circular/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Animales , Apoptosis/fisiología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Proteína Forkhead Box O3/genética , Ácido Glutámico/metabolismo , Ratones , Mitocondrias/efectos de los fármacos , Neuronas/metabolismo , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
13.
Int J Neurosci ; 130(2): 186-192, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31696761

RESUMEN

Background and Purpose: Oxidative stress is involved in the development of infections. However, whether oxidative stress indicators can be used as markers of stroke-associated infection (SAI) is still unclear. The purpose of this study was to test the predictive values of superoxide dismutase (SOD) and malondialdehyde (MDA) levels for SAI incidence.Methods: A total of 45 consecutive patients with ischemic stroke who were admitted to our hospital were enrolled. A prospective study was carried out to observe the occurrence of SAI during the first 7 days after stroke. Accordingly, the patients were divided into SAI and non-SAI groups. The relationship between SOD and MDA serum levels and SAI was analyzed.Results: The patients in the SAI group had significantly higher serum SOD levels than those in the non-SAI group (41.638 ± 3.428 U/ml vs. 36.542 ± 9.114 U/ml, p = 0.033). However, there were no significant differences in MDA levels between the SAI and non-SAI group (p > 0.05). The discriminating ability of serum SOD level for SAI was measured using an ROC curve. Serum level of SOD >38.16 U/ml was useful in diagnosing SAI with a sensitivity of 88% and a specificity of 61%. Kaplan-Meier curves showed that the group with serum SOD level >38.16 U/ml had higher rates of SAI incidence (χ2 = 9.688, p = 0.002; log rank test). Furthermore, Cox regression analysis indicated that a serum SOD level >38.16 U/ml was an independent risk factor for SAI (hazard ratio = 5.836; 95% CI, 1.298-26.244; p = 0.021).Conclusions: Acute-phase serum SOD level could be a predictor of SAI.


Asunto(s)
Isquemia Encefálica/sangre , Infecciones/sangre , Infecciones/diagnóstico , Inflamación/sangre , Estrés Oxidativo , Accidente Cerebrovascular/sangre , Superóxido Dismutasa/sangre , Anciano , Biomarcadores/sangre , Isquemia Encefálica/complicaciones , Femenino , Humanos , Infecciones/etiología , Inflamación/etiología , Masculino , Malondialdehído/sangre , Persona de Mediana Edad , Estrés Oxidativo/fisiología , Estudios Prospectivos , Sensibilidad y Especificidad , Accidente Cerebrovascular/complicaciones
14.
Neuroimage ; 187: 226-254, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30041061

RESUMEN

Early brain development, from the embryonic period to infancy, is characterized by rapid structural and functional changes. These changes can be studied using structural and physiological neuroimaging methods. In order to optimally acquire and accurately interpret this data, concepts from adult neuroimaging cannot be directly transferred. Instead, one must have a basic understanding of fetal and neonatal structural and physiological brain development, and the important modulators of this process. Here, we first review the major developmental milestones of transient cerebral structures and structural connectivity (axonal connectivity) followed by a summary of the contributions from ex vivo and in vivo MRI. Next, we discuss the basic biology of neuronal circuitry development (synaptic connectivity, i.e. ensemble of direct chemical and electrical connections between neurons), physiology of neurovascular coupling, baseline metabolic needs of the fetus and the infant, and functional connectivity (defined as statistical dependence of low-frequency spontaneous fluctuations seen with functional magnetic resonance imaging (fMRI)). The complementary roles of magnetic resonance imaging (MRI), electroencephalography (EEG), magnetoencephalography (MEG), and near-infrared spectroscopy (NIRS) are discussed. We include a section on modulators of brain development where we focus on the placenta and emerging placental MRI approaches. In each section we discuss key technical limitations of the imaging modalities and some of the limitations arising due to the biology of the system. Although neuroimaging approaches have contributed significantly to our understanding of early brain development, there is much yet to be done and a dire need for technical innovations and scientific discoveries to realize the future potential of early fetal and infant interventions to avert long term disease.


Asunto(s)
Encéfalo/diagnóstico por imagen , Encéfalo/embriología , Neuroimagen/métodos , Encéfalo/irrigación sanguínea , Encéfalo/fisiología , Mapeo Encefálico , Femenino , Edad Gestacional , Humanos , Lactante , Vías Nerviosas/irrigación sanguínea , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/embriología , Vías Nerviosas/fisiología , Acoplamiento Neurovascular , Embarazo , Sustancia Blanca/irrigación sanguínea , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/embriología , Sustancia Blanca/fisiología
15.
Am J Orthod Dentofacial Orthop ; 155(4): 584-591, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30935613

RESUMEN

Surgical interventions on the alveolar ridges aimed at facilitating orthodontic tooth movement have been extensively reported. However, unexpected events or complications still occur in daily practice. The purpose of this report was to present a novel 3-dimensional (3D) computer-assisted piezocision guide (CAPG) designed to be translucent for increased visibility, rigid for enhanced support during guidance, and porous for profuse irrigation during procedure. Such a design can function to minimize the risk of surgical complications. In this case, we present a novel 3D-printed CAPG to facilitate a minimally invasive periodontal accelerated osteogenic orthodontics (PAOO) procedure with a guide that provides accuracy, adequate visibility, and greater access for the coolant to reach the surgery site. By navigating the cone-beam computed tomography data, we precisely know the cortical bone thickness, root direction, and interrelations between anatomic structures in an individual situation, which allows us to design our cutting slot for the required length and depth according to the operator's knowledge. Finally, 3D printing was applied, transferring our surgical plan to fabricate the CAPG. Moreover, the well designed pores on the CAPG allow effective irrigation during the piezocision procedure. This minimally invasive procedure was uneventful, and no devitalized tooth or alveolar bone was found.


Asunto(s)
Procedimientos Quirúrgicos Ortognáticos/métodos , Piezocirugía/métodos , Impresión Tridimensional , Proceso Alveolar/cirugía , Femenino , Humanos , Maloclusión Clase I de Angle/cirugía , Persona de Mediana Edad , Ortodoncia Correctiva/métodos
16.
Am J Emerg Med ; 36(6): 988-992, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29117900

RESUMEN

OBJECTIVE: The diagnosis of shock in patients presenting to the emergency department (ED) is often challenging. We aimed to compare the accuracy of experienced emergency physician gestalt against Li's pragmatic shock (LiPS) tool for predicting the likelihood of shock in the emergency department, using 30-day mortality as an objective standard. METHOD: In a prospective observational study conducted in an urban, academic ED in Hong Kong, adult patients aged 18years or older admitted to the resuscitation room or high dependency unit were recruited. Eligible patients had a standard ED workup for shock. The emergency physician treating the patient was asked whether he or she considered shock to be probable, and this was compared with LiPS. The proxy 'gold' or reference standard was 30-day mortality. The area under the receiver operating curve (AUROC) was used to predict prognosis. The primary outcome measure was 30-day mortality. RESULTS: A total of 220 patients fulfilled the inclusion criteria and were included in the analysis. The AUROC for LiPS (0.722; sensitivity=0.733, specificity=0.711, P<0.0001) was greater than emergency physician gestalt (0.620, sensitivity=0.467, specificity=0.774, P=0.0137) for diagnosing shock using 30-day mortality as a proxy (difference P=0.0229). LiPS shock patients were 6.750 times (95%CI=2.834-16.076, P<0.0001) more likely to die within 30-days compared with non-shock patients. Patients diagnosed by emergency physicians were 2.991 times (95%CI=1.353-6.615, P=0.007) more likely to die compared with the same reference. CONCLUSIONS: LiPS has a higher diagnostic accuracy than emergency physician gestalt for shock when compared against an outcome of 30-day mortality.


Asunto(s)
Competencia Clínica , Servicio de Urgencia en Hospital , Choque/diagnóstico , Triaje/normas , Anciano , Femenino , Hong Kong/epidemiología , Mortalidad Hospitalaria/tendencias , Humanos , Masculino , Estudios Prospectivos , Curva ROC , Choque/mortalidad
18.
Int J Neurosci ; 127(3): 261-266, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27211997

RESUMEN

BACKGROUND AND PURPOSE: Detecting cardioembolic stroke soon after acute cerebral ischemia has a major impact on secondary stroke prevention. Recently, the Score for the Targeting of Atrial Fibrillation (STAF) was introduced to identify stroke patients at risk of atrial fibrillation. However, whether the STAF score could be a useful approach to differentiate cardioembolic stroke from other stroke subtypes is unclear. METHODS: Consecutive patients with acute ischemic stroke that were admitted to our stroke center were enrolled. Each patient was assessed (age, baseline National Institutes of Health Stroke Scale, left atrial dilatation and absence of vascular etiology) to calculate the STAF score. A follow-up visit was conducted for each patient during hospitalization to determine the diagnosed stroke etiology according to the Trial of Org 10172 in Acute Stroke Treatment criteria. RESULTS: The median and interquartile range of the STAF score was significantly higher in the cardioembolic than in the non-cardioembolic group [6 (2) vs. 2 (3), p < 0.001]. The discriminating ability of the STAF score model was good as demonstrated by the receiver operating characteristic curve. The area under the curve (AUC) of STAF score (AUC = 0.98; 95% CI, 0.96-0.99) was significantly greater than B-type natriuretic peptide (AUC = 0.87; 95% CI, 0.83-0.91) (p < 0.05). The optimal STAF cut-off value was ≥ 5, which diagnosed cardioembolic stroke with a sensitivity of 90% and specificity of 95%. CONCLUSIONS: The STAF score is a simple and accurate tool that can discriminate the cardioembolic stroke from other types during hospitalization for acute ischemic stroke.


Asunto(s)
Embolia Intracraneal/complicaciones , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/etiología , Adulto , Anciano , Anciano de 80 o más Años , China , Estudios de Cohortes , Electrocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC
19.
J Neurosci Res ; 94(7): 671-82, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26994698

RESUMEN

TAR DNA binding protein 43 (TDP-43) is a nuclear protein that has been shown to have altered homeostasis in the form of neuronal nuclear and cytoplasmic aggregates in some familial and almost all cases of sporadic amyotrophic lateral sclerosis as well as 51% of frontotemporal lobar degeneration and 57% of Alzheimer's disease cases. Heat shock proteins (HSPs), such as HSP70, recognize misfolded or aggregated proteins and refold, disaggregate, or turn them over and are upregulated by the master transcription factor heat shock factor 1 (HSF1). Here, we explore the effect of HSF1 overexpression on proteotoxic stress-related alterations in TDP-43 solubility, proteolytic processing, and cytotoxicity. HSF1 overexpression reduced TDP-43-positive puncta concomitantly with upregulating HSP70 and HSP90 protein levels. HSF1 overexpression or pharmacological activation sustained TDP-43 solubility and significantly reduced truncation of TDP-43 in response to inhibition of the proteasome with Z-Leu-Leu-Leu-al, and this was reversed by HSF1 inhibition. HSF1 activation conferred protection against toxicity associated with TDP-43 C-terminal fragments without globally increasing the activity of the ubiquitin proteasome system (UPS) while concomitantly reducing the induction of autophagy, suggesting that HSF1 protection is an early event. In support of this, inhibition of HSP70 ATPase activity further reduced TDP-43 solubility. HSF1 knockout significantly increased TDP-43 insolubility and accelerated TDP-43 fragmentation in response to proteotoxic stress. Overall, this study shows that HSF1 overexpression protects against TDP-43 pathology by upregulation of chaperones, especially HSP70, rather than enhancing autophagy or the UPS during times of proteotoxic stress. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Proteínas de Unión al ADN/química , Proteínas HSP70 de Choque Térmico/biosíntesis , Factores de Transcripción del Choque Térmico/genética , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Animales , Autofagia/genética , Línea Celular Tumoral , Células Cultivadas , Proteínas de Unión al ADN/toxicidad , Factores de Transcripción del Choque Térmico/biosíntesis , Humanos , Ratones , Ratones Noqueados , Cultivo Primario de Células , Complejo de la Endopetidasa Proteasomal/efectos de los fármacos , Solubilidad , Ubiquitina/metabolismo
20.
Am J Physiol Regul Integr Comp Physiol ; 311(6): R1022-R1031, 2016 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-27629889

RESUMEN

8-Prenylnaringenin (8-PN) is a prenylflavonoid that originates from hop extracts and is thought to help prevent disuse muscle atrophy. We hypothesized that 8-PN affects muscle plasticity by promoting muscle recovery under disuse muscle atrophy. To test the promoting effect of 8-PN on muscle recovery, we administered an 8-PN mixed diet to mice that had been immobilized with a cast to one leg for 14 days. Intake of the 8-PN mixed diet accelerated recovery from muscle atrophy, and prevented reductions in Akt phosphorylation. Studies on cell cultures of mouse myotubes in vitro demonstrated that 8-PN activated the PI3K/Akt/P70S6K1 pathway at physiological concentrations. A cell-culture study using an inhibitor of estrogen receptors and an in vivo experiment with ovariectomized mice suggested that the estrogenic activity of 8-PN contributed to recovery from disuse muscle atrophy through activation of an Akt phosphorylation pathway. These data strongly suggest that 8-PN is a naturally occurring compound that could be used as a nutritional supplement to aid recovery from disuse muscle atrophy.


Asunto(s)
Flavanonas/farmacología , Músculo Esquelético/fisiopatología , Atrofia Muscular/fisiopatología , Proteína Oncogénica v-akt/metabolismo , Recuperación de la Función/fisiología , Transducción de Señal , Animales , Línea Celular , Activación Enzimática/efectos de los fármacos , Flavanonas/administración & dosificación , Suspensión Trasera , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Musculares/metabolismo , Músculo Esquelético/efectos de los fármacos , Atrofia Muscular/tratamiento farmacológico , Fosforilación/efectos de los fármacos , Fitoestrógenos/administración & dosificación , Fitoestrógenos/farmacología , Biosíntesis de Proteínas/efectos de los fármacos , Recuperación de la Función/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Resultado del Tratamiento
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