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1.
Proc Natl Acad Sci U S A ; 121(18): e2322520121, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38657044

RESUMEN

The S-phase checkpoint involving CHK1 is essential for fork stability in response to fork stalling. PARP1 acts as a sensor of replication stress and is required for CHK1 activation. However, it is unclear how the activity of PARP1 is regulated. Here, we found that UFMylation is required for the efficient activation of CHK1 by UFMylating PARP1 at K548 during replication stress. Inactivation of UFL1, the E3 enzyme essential for UFMylation, delayed CHK1 activation and inhibits nascent DNA degradation during replication blockage as seen in PARP1-deficient cells. An in vitro study indicated that PARP1 is UFMylated at K548, which enhances its catalytic activity. Correspondingly, a PARP1 UFMylation-deficient mutant (K548R) and pathogenic mutant (F553L) compromised CHK1 activation, the restart of stalled replication forks following replication blockage, and chromosome stability. Defective PARP1 UFMylation also resulted in excessive nascent DNA degradation at stalled replication forks. Finally, we observed that PARP1 UFMylation-deficient knock-in mice exhibited increased sensitivity to replication stress caused by anticancer treatments. Thus, we demonstrate that PARP1 UFMylation promotes CHK1 activation and replication fork stability during replication stress, thus safeguarding genome integrity.


Asunto(s)
Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1) , Replicación del ADN , Poli(ADP-Ribosa) Polimerasa-1 , Animales , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Poli(ADP-Ribosa) Polimerasa-1/genética , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/metabolismo , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/genética , Ratones , Humanos , Daño del ADN , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética
2.
Proc Natl Acad Sci U S A ; 119(40): e2203783119, 2022 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-36161901

RESUMEN

ASPM is a protein encoded by primary microcephaly 5 (MCPH5) and is responsible for ensuring spindle position during mitosis and the symmetrical division of neural stem cells. We recently reported that ASPM promotes homologous recombination (HR) repair of DNA double strand breaks. However, its potential role in DNA replication and replication stress response remains elusive. Interestingly, we found that ASPM is dispensable for DNA replication under unperturbed conditions. However, ASPM is enriched at stalled replication forks in a RAD17-dependent manner in response to replication stress and promotes RAD9 and TopBP1 loading onto chromatin, facilitating ATR-CHK1 activation. ASPM depletion results in failed fork restart and nuclease MRE11-mediated nascent DNA degradation at the stalled replication fork. The overall consequence is chromosome instability and the sensitization of cancer cells to replication stressors. These data support a role for ASPM in loading RAD17-RAD9/TopBP1 onto chromatin to activate the ATR-CHK1 checkpoint and ultimately ensure genome stability.


Asunto(s)
Proteínas de la Ataxia Telangiectasia Mutada , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1) , Replicación del ADN , Proteínas del Tejido Nervioso , Animales , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Proteínas Portadoras/metabolismo , Proteínas de Ciclo Celular/metabolismo , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/genética , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/metabolismo , Cromatina/genética , Reparación del ADN/genética , Replicación del ADN/genética , Proteínas de Unión al ADN/metabolismo , Células HeLa , Humanos , Ratones , Microcefalia/genética , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/fisiología , Proteínas Nucleares/metabolismo
3.
Glia ; 72(8): 1484-1500, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38780213

RESUMEN

Microglia are innate immune cells in the brain and show exceptional heterogeneity. They are key players in brain physiological development regulating synaptic plasticity and shaping neuronal networks. In pathological disease states, microglia-induced synaptic pruning mediates synaptic loss and targeting microglia was proposed as a promising therapeutic strategy. However, the effect of microglia depletion and subsequent repopulation on dendritic spine density and neuronal function in the adult brain is largely unknown. In this study, we investigated whether pharmacological microglia depletion affects dendritic spine density after long-term permanent microglia depletion and after short-term microglia depletion with subsequent repopulation. Long-term microglia depletion using colony-stimulating-factor-1 receptor (CSF1-R) inhibitor PLX5622 resulted in increased overall spine density, especially of mushroom spines, and increased excitatory postsynaptic current amplitudes. Short-term PLX5622 treatment with subsequent repopulation of microglia had an opposite effect resulting in activated microglia with increased synaptic phagocytosis and consequently decreased spine density and reduced excitatory neurotransmission, while Barnes maze and elevated plus maze testing was unaffected. Moreover, RNA sequencing data of isolated repopulated microglia showed an activated and proinflammatory phenotype. Long-term microglia depletion might be a promising therapeutic strategy in neurological diseases with pathological microglial activation, synaptic pruning, and synapse loss. However, repopulation after depletion induces activated microglia and results in a decrease of dendritic spines possibly limiting the therapeutic application of microglia depletion. Instead, persistent modulation of pathological microglia activity might be beneficial in controlling synaptic damage.


Asunto(s)
Encéfalo , Espinas Dendríticas , Ratones Endogámicos C57BL , Microglía , Animales , Microglía/efectos de los fármacos , Microglía/metabolismo , Espinas Dendríticas/efectos de los fármacos , Masculino , Ratones , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Potenciales Postsinápticos Excitadores/fisiología , Fagocitosis/fisiología , Fagocitosis/efectos de los fármacos , Plasticidad Neuronal/fisiología , Plasticidad Neuronal/efectos de los fármacos , Ratones Transgénicos , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/antagonistas & inhibidores , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Compuestos Orgánicos
4.
Biochem Biophys Res Commun ; 695: 149421, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38171233

RESUMEN

In mammalian brain development, WNT signaling balances proliferation and differentiation of neural progenitor cells, and is essential for the maintenance of regular brain development. JADE1 is a candidate transcription co-factor essential for DNA replication, cell division, and cell cycle regulation. In 293T cells, JADE1 is stabilized by von Hippel-Lindau protein pVHL, promotes the ß-catenin ubiquitination and thus blunts canonical WNT signaling. Furthermore, JADE1 inhibits ß-catenin-induced ectopic axis formation in Xenopus embryos. However, JADE1's role in mammalian brain development remains unknown. Here, we generated a new Jade1 knockout mouse line using CRISPR-Cas9 technology. We found that JADE1 null resulted in decreased survival rate, reduced body weight and brain weight in mice. However, histological analysis revealed a normal brain development. Furthermore, Jade1 null neural progenitor cells proliferated normally in vivo and in vitro. RNA-seq analysis further showed that JADE1 loss did not affect the cerebral cortex gene expression. Our findings indicate that JADE1 is dispensable for developing the cerebral cortex in mice.


Asunto(s)
Encéfalo , Proteínas de Homeodominio , Animales , Ratones , beta Catenina/metabolismo , Encéfalo/crecimiento & desarrollo , Encéfalo/metabolismo , Diferenciación Celular , Proliferación Celular , Proteínas de Homeodominio/metabolismo , Mamíferos/metabolismo , Ratones Noqueados , Vía de Señalización Wnt/fisiología
5.
Eur Radiol ; 34(1): 485-494, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37540319

RESUMEN

OBJECTIVES: To investigate the MRI radiomics signatures in predicting pathologic response among patients with locally advanced esophageal squamous cell carcinoma (ESCC), who received neoadjuvant chemotherapy (NACT). METHODS: Patients who underwent NACT from March 2015 to October 2019 were prospectively included. Each patient underwent esophageal MR scanning within one week before NACT and within 2-3 weeks after completion of NACT, prior to surgery. Radiomics features extracted from T2-TSE-BLADE were randomly split into the training and validation sets at a ratio of 7:3. According to the progressive tumor regression grade (TRG), patients were stratified into two groups: good responders (GR, TRG 0 + 1) and poor responders (non-GR, TRG 2 + 3). We constructed the Pre/Post-NACT model (Pre/Post-model) and the Delta-NACT model (Delta-model). Kruskal-Wallis was used to select features, logistic regression was used to develop the final model. RESULTS: A total of 108 ESCC patients were included, and 3/2/4 out of 107 radiomics features were selected for constructing the Pre/Post/Delta-model, respectively. The selected radiomics features were statistically different between GR and non-GR groups. The highest area under the curve (AUC) was for the Delta-model, which reached 0.851 in the training set and 0.831 in the validation set. Among the three models, Pre-model showed the poorest performance in the training and validation sets (AUC, 0.466 and 0.596), and the Post-model showed better performance than the Pre-model in the training and validation sets (AUC, 0.753 and 0.781). CONCLUSIONS: MRI-based radiomics models can predict the pathological response after NACT in ESCC patients, with the Delta-model exhibiting optimal predictive efficacy. CLINICAL RELEVANCE STATEMENT: MRI radiomics features could be used as a useful tool for predicting the efficacy of neoadjuvant chemotherapy in esophageal carcinoma patients, especially in selecting responders among those patients who may be candidates to benefit from neoadjuvant chemotherapy. KEY POINTS: • The MRI radiomics features based on T2WI-TSE-BLADE could potentially predict the pathologic response to NACT among ESCC patients. • The Delta-model exhibited the best predictive ability for pathologic response, followed by the Post-model, which similarly had better predictive ability, while the Pre-model performed less well in predicting TRG.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/diagnóstico por imagen , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/tratamiento farmacológico , Terapia Neoadyuvante , Radiómica , Imagen por Resonancia Magnética , Estudios Retrospectivos
6.
Mol Cell ; 64(3): 580-592, 2016 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-27814490

RESUMEN

The Mre11/Rad50/Nbs1 complex initiates double-strand break repair by homologous recombination (HR). Loss of Mre11 or its nuclease activity in mouse cells is known to cause genome aberrations and cellular senescence, although the molecular basis for this phenotype is not clear. To identify the origin of these defects, we characterized Mre11-deficient (MRE11-/-) and nuclease-deficient Mre11 (MRE11-/H129N) chicken DT40 and human lymphoblast cell lines. These cells exhibit increased spontaneous chromosomal DSBs and extreme sensitivity to topoisomerase 2 poisons. The defects in Mre11 compromise the repair of etoposide-induced Top2-DNA covalent complexes, and MRE11-/- and MRE11-/H129N cells accumulate high levels of Top2 covalent conjugates even in the absence of exogenous damage. We demonstrate that both the genome instability and mortality of MRE11-/- and MRE11-/H129N cells are significantly reversed by overexpression of Tdp2, an enzyme that eliminates covalent Top2 conjugates; thus, the essential role of Mre11 nuclease activity is likely to remove these lesions.


Asunto(s)
Antígenos de Neoplasias/genética , Roturas del ADN de Doble Cadena/efectos de los fármacos , ADN-Topoisomerasas de Tipo II/genética , Proteínas de Unión al ADN/genética , ADN/genética , Proteínas Nucleares/genética , Reparación del ADN por Recombinación/efectos de los fármacos , Factores de Transcripción/genética , Ácido Anhídrido Hidrolasas , Animales , Antígenos de Neoplasias/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Pollos , ADN/metabolismo , Enzimas Reparadoras del ADN/genética , Enzimas Reparadoras del ADN/metabolismo , ADN-Topoisomerasas de Tipo II/metabolismo , Proteínas de Unión al ADN/deficiencia , Proteínas de Unión al ADN/metabolismo , Etopósido/farmacología , Regulación de la Expresión Génica , Inestabilidad Genómica/efectos de los fármacos , Humanos , Linfocitos/citología , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Proteína Homóloga de MRE11 , Mutación , Proteínas Nucleares/metabolismo , Hidrolasas Diéster Fosfóricas , Proteínas de Unión a Poli-ADP-Ribosa , Transducción de Señal , Inhibidores de Topoisomerasa II/farmacología , Factores de Transcripción/metabolismo
7.
J Chem Phys ; 160(20)2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38804489

RESUMEN

The thermophysical properties and elemental abundances of the noble gases in terrestrial materials can provide unique insights into the Earth's evolution and mantle dynamics. Here, we perform extensive ab initio molecular dynamics simulations to determine the melting temperature and sound velocity of neon up to 370 GPa and 7500 K to constrain its physical state and storage capacity, together with to reveal its implications for the deep interior of the Earth. It is found that solid neon can exist stably under the lower mantle and inner core conditions, and the abnormal melting of neon is not observed under the entire temperature (T) and pressure (P) region inside the Earth owing to its peculiar electronic structure, which is substantially distinct from other heavier noble gases. An inspection of the reduction for sound velocity along the Earth's geotherm evidences that neon can be used as a light element to account for the low-velocity anomaly and density deficit in the deep Earth. A comparison of the pair distribution functions and mean square displacements of MgSiO3-Ne and Fe-Ne alloys further reveals that MgSiO3 has a larger neon storage capacity than the liquid iron under the deep Earth condition, indicating that the lower mantle may be a natural deep noble gas storage reservoir. Our results provide valuable information for studying the fundamental behavior and phase transition of neon in a higher T-P regime, and further enhance our understanding for the interior structure and evolution processes inside the Earth.

8.
BMC Anesthesiol ; 24(1): 98, 2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38459441

RESUMEN

BACKGROUND: To evaluate the postoperative morbidity and mortality of patients undergoing cardiovascular surgery during the 2022 nationwide Omicron variant infection wave in China. METHODS: This retrospective cohort study included 403 patients who underwent cardiovascular surgery for the first time during the 2022 wave of the pandemic within 1 month. Among them, 328 patients were preoperatively diagnosed with COVID-19 Omicron variant infection during the pandemic, and 75 patients were negative. The association between Omicron variant exposure and postoperative prognosis was explored by comparing patients with and without COVID-19 exposure. The primary outcome was in-hospital death after cardiovascular surgery. The secondary outcomes were major postoperative morbidity, including myocardial infarction (MI), acute kidney injury (AKI), postoperative mechanical ventilation hours, ICU stay hours, and postoperative length of stay. The data were analyzed using inverse probability of treatment weighting (IPTW) to minimize bias. RESULTS: We identified 403 patients who underwent cardiovascular surgery, 328 (81.39%) had Omicron variant infections. In total, 10 patients died in the hospital. Omicron variant infection was associated with a much greater risk of death during cardiovascular surgery after adjustment for IPTW (2.8% vs. 1.3%, adjusted OR 2.185, 95%CI = 1.193 to 10.251, P = 0.041). For major postoperative morbidity, there were no significant differences in terms of myocardial infarction between the two groups (adjusted OR = 0.861, 95%CI = 0.444 to 1.657, P = 0.653), acute kidney injury (adjusted OR = 1.157, 95%CI = 0.287 to 5.155, P = 0.820), postoperative mechanical ventilation hours (B -0.375, 95%CI=-8.438 to 7.808, P = 0.939), ICU stay hours (B 2.452, 95%CI=-13.269 to 8.419, P = 0.660) or postoperative stay (B -1.118, 95%CI=-2.237 to 1.154, P = 0.259) between the two groups. CONCLUSION: Perioperative COVID-19 infection was associated with an increased risk of in-hospital death among patients who underwent cardiovascular surgery during the Omicron variant wave of the pandemic.


Asunto(s)
Lesión Renal Aguda , COVID-19 , Infarto del Miocardio , Humanos , Pandemias , Estudios Retrospectivos , Mortalidad Hospitalaria , COVID-19/epidemiología , Complicaciones Posoperatorias/epidemiología , SARS-CoV-2 , Morbilidad , Infarto del Miocardio/epidemiología , Lesión Renal Aguda/epidemiología , Lesión Renal Aguda/etiología
9.
Int J Mol Sci ; 25(9)2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38731817

RESUMEN

MCPH1 has been identified as the causal gene for primary microcephaly type 1, a neurodevelopmental disorder characterized by reduced brain size and delayed growth. As a multifunction protein, MCPH1 has been reported to repress the expression of TERT and interact with transcriptional regulator E2F1. However, it remains unclear whether MCPH1 regulates brain development through its transcriptional regulation function. This study showed that the knockout of Mcph1 in mice leads to delayed growth as early as the embryo stage E11.5. Transcriptome analysis (RNA-seq) revealed that the deletion of Mcph1 resulted in changes in the expression levels of a limited number of genes. Although the expression of some of E2F1 targets, such as Satb2 and Cdkn1c, was affected, the differentially expressed genes (DEGs) were not significantly enriched as E2F1 target genes. Further investigations showed that primary and immortalized Mcph1 knockout mouse embryonic fibroblasts (MEFs) exhibited cell cycle arrest and cellular senescence phenotype. Interestingly, the upregulation of p19ARF was detected in Mcph1 knockout MEFs, and silencing p19Arf restored the cell cycle and growth arrest to wild-type levels. Our findings suggested it is unlikely that MCPH1 regulates neurodevelopment through E2F1-mediated transcriptional regulation, and p19ARF-dependent cell cycle arrest and cellular senescence may contribute to the developmental abnormalities observed in primary microcephaly.


Asunto(s)
Puntos de Control del Ciclo Celular , Senescencia Celular , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Microcefalia , Animales , Ratones , Puntos de Control del Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Senescencia Celular/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Inhibidor p16 de la Quinasa Dependiente de Ciclina/deficiencia , Factor de Transcripción E2F1/genética , Factor de Transcripción E2F1/metabolismo , Fibroblastos/metabolismo , Ratones Noqueados , Microcefalia/genética , Microcefalia/metabolismo , Microcefalia/patología
10.
Pak J Med Sci ; 40(6): 1174-1179, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38952528

RESUMEN

Objective: To explore the clinical effect of laser acupuncture combined with Schroth therapy on adolescent idiopathic scoliosis (AIS). Method: This was a retrospective study. Eighty AIS patients were admitted to The Second People's Hospital of Dalian from March 2021 to March 2022 and divided into control group and experimental group according to the treatment method, with 40 cases in each group. The control group received Schroth therapy, and the experimental group received Schroth therapy and laser acupuncture therapy (MLS® laser). All treatments are performed five times a week for four consecutive weeks we compared the clinical effects of the two groups before treatment, six months and 12 months after treatment, and compared the improvement of Cobb angle, axial trunk rotation (ATR), musculoskeletal stiffness(The PulStarG3 system), and gait evaluation (Micro-Electro-Mechanical System(MEMS) between the two groups of patients. Result: After four weeks of treatment, the spinal condition of both groups of patients improved. After treatment, the experimental group showed greater improvement in Cobb angle, ATR, spinal range of motion, gait parameters, and clinical efficacy compared to the control group (p<0.05). Conclusion: Laser acupuncture combined with Schroth therapy is safe and effective in the treatment of AIS, and is more effective in correcting scoliosis and related problems of AIS.

11.
Am J Hum Genet ; 107(2): 364-373, 2020 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-32707086

RESUMEN

We report bi-allelic pathogenic HPDL variants as a cause of a progressive, pediatric-onset spastic movement disorder with variable clinical presentation. The single-exon gene HPDL encodes a protein of unknown function with sequence similarity to 4-hydroxyphenylpyruvate dioxygenase. Exome sequencing studies in 13 families revealed bi-allelic HPDL variants in each of the 17 individuals affected with this clinically heterogeneous autosomal-recessive neurological disorder. HPDL levels were significantly reduced in fibroblast cell lines derived from more severely affected individuals, indicating the identified HPDL variants resulted in the loss of HPDL protein. Clinical presentation ranged from severe, neonatal-onset neurodevelopmental delay with neuroimaging findings resembling mitochondrial encephalopathy to milder manifestation of adolescent-onset, isolated hereditary spastic paraplegia. All affected individuals developed spasticity predominantly of the lower limbs over the course of the disease. We demonstrated through bioinformatic and cellular studies that HPDL has a mitochondrial localization signal and consequently localizes to mitochondria suggesting a putative role in mitochondrial metabolism. Taken together, these genetic, bioinformatic, and functional studies demonstrate HPDL is a mitochondrial protein, the loss of which causes a clinically variable form of pediatric-onset spastic movement disorder.


Asunto(s)
Encefalopatías/genética , Proteínas Mitocondriales/genética , Enfermedades Neurodegenerativas/genética , Paraplejía Espástica Hereditaria/genética , Adolescente , Adulto , Alelos , Secuencia de Aminoácidos , Niño , Femenino , Humanos , Masculino , Mitocondrias/genética , Linaje , Fenotipo , Adulto Joven
12.
Neuropathol Appl Neurobiol ; 49(4): e12915, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37296499

RESUMEN

AIMS: Nijmegen breakage syndrome (NBS) is a rare autosomal recessive disorder caused by hypomorphic mutations of NBS1. NBS1 is a member of the MRE11-RAD50-NBS1 (MRN) complex that binds to DNA double-strand breaks and activates the DNA damage response (DDR). Nbs1 inactivation in neural progenitor cells leads to microcephaly and premature death. Interestingly, p53 homozygous deletion rescues the NBS1-deficient phenotype allowing long-term survival. The objective of this work was to determine whether simultaneous inactivation of Nbs1 and p53 in neural progenitors triggered brain tumorigenesis and if so in which category this tumour could be classified. METHODS: We generated a mouse model with simultaneous genetic inactivation of Nbs1 and p53 in embryonic neural stem cells and analysed the arising tumours with in-depth molecular analyses including immunohistochemistry, array comparative genomic hybridisation (aCGH), whole exome-sequencing and RNA-sequencing. RESULTS: NBS1/P53-deficient mice develop high-grade gliomas (HGG) arising in the olfactory bulbs and in the cortex along the rostral migratory stream. In-depth molecular analyses using immunohistochemistry, aCGH, whole exome-sequencing and RNA-sequencing revealed striking similarities to paediatric human HGG with shared features with radiation-induced gliomas (RIGs). CONCLUSIONS: Our findings show that concomitant inactivation of Nbs1 and p53 in mice promotes HGG with RIG features. This model could be useful for preclinical studies to improve the prognosis of these deadly tumours, but it also highlights the singularity of NBS1 among the other DNA damage response proteins in the aetiology of brain tumours.


Asunto(s)
Glioma , Proteína p53 Supresora de Tumor , Animales , Niño , Humanos , Ratones , Proteínas de Ciclo Celular/genética , Glioma/genética , Homocigoto , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Eliminación de Secuencia , Proteína p53 Supresora de Tumor/genética
13.
Eur Radiol ; 33(7): 4962-4972, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36692595

RESUMEN

OBJECTIVES: To compare between the diagnostic performance of 3.0-T MRI and CT for aorta and tracheobronchial invasion in patients with esophageal cancer (EC). METHODS: We prospectively included patients with pathologically confirmed EC from November 2018 to June 2021, who had baseline stage of T3-4N0-2M0 and restaging after neoadjuvant chemotherapy. All patients underwent contrast-enhanced CT and MRI of the thorax. Two independent blinded radiologists scored image quality and the presence of invasion. Agreements between the two readers were calculated using kappa test. The sensitivity, specificity, accuracy, positive predict value (PPV), and negative predict value (NPV) of MRI and CT in evaluating invasion were calculated. The net reclassification index (NRI) was used to evaluate the change in the number of patients correctly classified by MRI and CT. RESULTS: A total of 70 patients (64.8 ± 9.0 years; 53 men) were enrolled. Inter-reader agreements of image quality scores and presence of invasion by MRI and CT between the two readers were almost perfect (kappa > 0.80). The accuracy of MRI in evaluating thoracic aorta invasion was significantly higher than that of CT (reader 1: 90.0% vs. 71.4%; reader 2: 92.9% vs. 70.0%, respectively), and the accuracy of MRI in evaluating tracheobronchial invasion also was significantly higher than that of CT (reader 1: 92.9% vs. 72.9%; reader 2: 95.7% vs. 70.0%, respectively). NRI values were positive in both the evaluation of aorta and tracheobronchial invasion. CONCLUSIONS: The accuracy of 3-T MRI in determining thoracic aorta and tracheobronchial invasion is significantly higher than that of CT. KEY POINTS: • 3.0-T MRI was significantly more accurate than CT in assessing invasion of the thoracic aorta in patients with esophageal cancer. • 3.0-T MRI was also significantly more accurate than CT in assessing tracheobronchial invasion in patients with esophageal cancer. • 3.0-T MRI has a higher diagnostic performance than CT in evaluating patients with suspected aortic or tracheobronchial invasion in esophageal cancer.


Asunto(s)
Neoplasias Esofágicas , Masculino , Humanos , Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/tratamiento farmacológico , Aorta/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Imagen por Resonancia Magnética/métodos , Sensibilidad y Especificidad
14.
Eur Radiol ; 33(12): 9233-9243, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37482548

RESUMEN

OBJECTIVES: To describe the specific MRI characteristics of different pathologic subtypes of esophageal carcinoma (EC) METHODS: This prospective study included EC patients who underwent esophageal MRI and esophagectomy between April 2015 and October 2021. Pathomorphological characteristics of EC such as localized type (LT), ulcerative type (UT), protruding type (PT), and infiltrative type (IT) were assessed by two radiologists relying on the imaging characteristics of tumor, especially the specific imaging findings on the continuity of the mucosa overlying the tumor, the opposing mucosa, mucosa linear thickening, and transmural growth pattern. Intraclass correlation coefficients (ICC) were calculated for the consistency between two readers. The associations of imaging characteristics with different pathologic subtypes were assessed using multilogistic regression model (MLR). RESULTS: A total of 201 patients were identified on histopathology with a high inter-reader agreement (ICC = 0.991). LT showed intact mucosa overlying the tumor. IT showed transmural growth pattern extending from the mucosa to the adventitia and a "sandwich" appearance. The remaining normal mucosa on the opposing side was linear and nodular in UT. PT showed correlation with T1 staging and grade 1; IT showed correlation with T3 staging and grades 2-3. Four MLR models showed high predictive performance on the test set with AUCs of 0.94 (LT), 0.87 (PT), 0.96 (IT), and 0.97 (UT), respectively, and the predictors that contributed most to the models matched the four specific characteristics. CONCLUSIONS: Different pathologic subtypes of EC displayed specific MR imaging characteristics, which could help predict T staging and the degree of pathological differentiation. CLINICAL RELEVANCE STATEMENT: Different pathologic subtypes of esophageal carcinoma displayed specific MR imaging characteristics, which correspond to differences in the degree of differentiation, T staging, and sensitivity to radiotherapy, and could also be one of the predictive factors of cause-specific survival and local progression-free rates. KEY POINTS: Different types of EC had different characteristics on MR images. A total of 91/95 (96%) LTEC showed intact mucosa over the tumor, while masses or nodules are specific to PTEC; 21/27 (78%) ITEC showed a "sandwich" sign; and 33/35 (60%) UTEC showed linear and nodular opposing mucosa. In the association of tumor type with degree of differentiation and T staging, PTEC was predominantly associated with T1 and grade 1, and ITEC was associated with T3 and grades 2-3, while LTEC and UECT were likewise primarily linked with T2-3 and grades 2-3.


Asunto(s)
Carcinoma , Neoplasias Esofágicas , Humanos , Estudios Prospectivos , Imagen por Resonancia Magnética/métodos , Carcinoma/patología , Neoplasias Esofágicas/patología , Estadificación de Neoplasias
15.
Phys Chem Chem Phys ; 25(45): 31312-31325, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37955953

RESUMEN

Two-dimensional (2D) materials have been one of the most popular objects in the research field of thermoelectric (TE) materials and have attracted substantial attention in recent years. Inspired by the synthesized 2H-MoSSe and numerous theoretical studies, we systematically investigated the electronic, thermal, and TE properties of Janus 2H-MXTe (M = Zr and Hf; X = S and Se) monolayers by using first-principles calculations. The phonon dispersion curves and AIMD simulations confirm the thermodynamic stabilities. Moreover, Janus 2H-MXTe were evaluated as indirect band-gap semiconductors with band gaps ranging from 0.56 to 0.90 eV using the HSE06 + SOC method. To evaluate the TE performance, firstly, we calculated the temperature-dependent carrier relaxation time with acoustic phonon scattering τac, impurity scattering τimp, and polarized scattering τpol. Secondly, the calculation of lattice thermal conductivity (κl) shows that these monolayers possess relatively poor κl with values of 3.4-5.4 W mK-1 at 300 K, which is caused by the low phonon lifetime and group velocity. After computing the electronic transport properties, we found that the n-type doped Janus 2H-MXTe monolayers exhibit a high Seebeck coefficient exceeding 200 µV K-1 at 300 K, resulting in a high TE power factor. Eventually, combining the electrical and thermal conductivities, the optimal dimensionless figure of merit (zT) at 300 K (900 K) can be obtained, which is 0.94 (3.63), 0.51 (2.57), 0.64 (2.72), and 0.50 (1.98) for n-type doping of ZrSeTe, HfSeTe, ZeSTe, and HfSTe monolayers. Particularly, the ZrSeTe monolayer shows the best TE performance with the maximal zT value. These results indicate the excellent application potential of Janus 2H-MXTe (M = Zr and Hf; X = S and Se) monolayers in TE materials.

16.
Phys Chem Chem Phys ; 25(38): 26152-26163, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37740346

RESUMEN

Inspired by the interesting and novel properties exhibited by Janus transition metal dichalcogenides (TMDs) and two-dimensional pentagonal structures, we here investigated the structural stability, mechanical, electronic, photocatalytic, and optical properties for a class of two-dimensional (2D) pentagonal Janus TMDs, namely penta-MSeTe (M = Ni, Pd, Pt) monolayers, by using density functional theory (DFT) combined with Hubbard's correction (U). Our results showed that these monolayers exhibit good structural stability, appropriate band structures for photocatalysts, high visible light absorption, and good photocatalytic applicability. The calculated electronic properties reveal that the penta-MSeTe are semiconductors with a bandgap range of 2.06-2.39 eV, and their band edge positions meet the requirements for water-splitting photocatalysts in various environments (pH = 0-13). We used stress engineering to seek higher solar-to-hydrogen (STH) efficiency in acidic (pH = 0), neutral (pH = 7) and alkaline (pH = 13) environments for penta-MSeTe from 0% to +8% biaxial and uniaxial strains. Our results showed that penta-PdSeTe stretched 8% along the y direction and demonstrates an STH efficiency of up to 29.71% when pH = 0, which breaks the theoretical limit of the conventional photocatalytic model. We also calculated the optical properties and found that they exhibit high absorption (13.11%) in the visible light range and possess a diverse range of hyperbolic regions. Hence, it is anticipated that penta-MSeTe materials hold great promise for applications in photocatalytic water splitting and optoelectronic devices.

17.
Nature ; 541(7635): 87-91, 2017 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-28002403

RESUMEN

XRCC1 is a molecular scaffold protein that assembles multi-protein complexes involved in DNA single-strand break repair. Here we show that biallelic mutations in the human XRCC1 gene are associated with ocular motor apraxia, axonal neuropathy, and progressive cerebellar ataxia. Cells from a patient with mutations in XRCC1 exhibited not only reduced rates of single-strand break repair but also elevated levels of protein ADP-ribosylation. This latter phenotype is recapitulated in a related syndrome caused by mutations in the XRCC1 partner protein PNKP and implicates hyperactivation of poly(ADP-ribose) polymerase/s as a cause of cerebellar ataxia. Indeed, remarkably, genetic deletion of Parp1 rescued normal cerebellar ADP-ribose levels and reduced the loss of cerebellar neurons and ataxia in Xrcc1-defective mice, identifying a molecular mechanism by which endogenous single-strand breaks trigger neuropathology. Collectively, these data establish the importance of XRCC1 protein complexes for normal neurological function and identify PARP1 as a therapeutic target in DNA strand break repair-defective disease.


Asunto(s)
Ataxia Cerebelosa/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Mutación , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Adenosina Difosfato Ribosa/metabolismo , Alelos , Animales , Apraxias/congénito , Apraxias/genética , Ataxia/genética , Axones/patología , Ataxia Cerebelosa/patología , Cerebelo/metabolismo , Cerebelo/patología , Cromatina/metabolismo , Síndrome de Cogan/genética , Roturas del ADN de Cadena Simple , Reparación del ADN/genética , Enzimas Reparadoras del ADN/genética , Enzimas Reparadoras del ADN/metabolismo , Proteínas de Unión al ADN/deficiencia , Femenino , Humanos , Interneuronas/metabolismo , Interneuronas/patología , Masculino , Ratones , Linaje , Fenotipo , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Poli(ADP-Ribosa) Polimerasa-1/deficiencia , Poli(ADP-Ribosa) Polimerasa-1/genética , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X
18.
Food Microbiol ; 110: 104164, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36462820

RESUMEN

Since the first SARS-CoV-2 outbreak in Wuhan, China, there has been continued concern over the link between SARS-CoV-2 transmission and food. However, there are few studies on the viability and removal of SARS-CoV-2 contaminating food. This study aimed to evaluate the viability of SARS-CoV-2 on food matrices, depending on storage temperature, and inactivate the virus contaminating food using disinfectants. Two SARS-CoV-2 strains (L and S types) were used to contaminate lettuce, chicken, and salmon, which were then stored at 20,4 and -40 °C. The half-life of SARS-CoV-2 at 20 °C was 3-7 h but increased to 24-46 h at 4 °C and exceeded 100 h at -40 °C. SARS-CoV-2 persisted longer on chicken or salmon than on lettuce. Treatment with 70% ethanol for 1 min inactivated 3.25 log reduction of SARS-CoV-2 inoculated on lettuce but not on chicken and salmon. ClO2 inactivated up to 2 log reduction of SARS-CoV-2 on foods. Peracetic acid was able to eliminate SARS-CoV-2 from all foods. The virucidal effect of all disinfectants used in this study did not differ between the two SARS-CoV-2 strains; therefore, they could also be effective against other SARS-CoV-2 variants. This study demonstrated that the viability of SARS-CoV-2 can be extended at 4 and -40 °C and peracetic acid can inactivate SARS-CoV-2 on food matrices.


Asunto(s)
COVID-19 , Desinfectantes , Animales , Ácido Peracético/farmacología , Salmón , SARS-CoV-2 , Lactuca , Pollos , Etanol , Alimentos Marinos , Desinfectantes/farmacología
19.
Food Control ; 143: 109306, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35975280

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected more than 269 million people and killed more than 5.3 million people worldwide. Although fomite transmission of SARS-CoV-2 has been continuously reported, few studies have been conducted on food contact surfaces. Therefore, this study aimed to investigate the viability of coronaviruses on food contact surfaces and to remove SARS-CoV-2 contaminated on food contact surfaces with disinfectants. At 20 °C, SARS-CoV-2 was inactivated within 48 h on all food contact surfaces. At 4 °C, it was inactivated at 48 h on kraft paper and 96 h on parchment paper, but it was viable up to 5 days in low-density polyethylene (LDPE). At -20 °C, SARS-CoV-2 did not decrease by even 1 log on all food contact surfaces until 5 days. Treatment with 70% ethanol or 1000 ppm sodium hypochlorite for 5 min was sufficient to completely remove SARS-CoV-2 from 6 food contact surfaces. Similarly, UV-C irradiation at 60 mJ/cm2 eliminated SARS-CoV-2 contaminated on food contact surfaces. Also, the wiping test showed that even wiping an area contaminated with SARS-CoV-2 with a cloth moistened with 70% ethanol or 1000 ppm sodium hypochlorite, it took 5 min to inactivate the virus. Our findings suggested that SARS-CoV-2 contaminated on food contact surfaces in local retail may be viable enough to be transported home. However, if the type and method of use of the disinfectant suggested in this study are followed, it is possible to sufficiently control the fomite transmission of SARS-CoV-2 through food contact surfaces at home.

20.
EMBO J ; 37(21)2018 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-30237309

RESUMEN

The tuberous sclerosis complex (TSC) 1/2 is a negative regulator of the nutrient-sensing kinase mechanistic target of rapamycin complex (mTORC1), and its function is generally associated with tumor suppression. Nevertheless, biallelic loss of function of TSC1 or TSC2 is rarely found in malignant tumors. Here, we show that TSC1/2 is highly expressed in Burkitt's lymphoma cell lines and patient samples of human Burkitt's lymphoma, a prototypical MYC-driven cancer. Mechanistically, we show that MYC induces TSC1 expression by transcriptional activation of the TSC1 promoter and repression of miR-15a. TSC1 knockdown results in elevated mTORC1-dependent mitochondrial respiration enhanced ROS production and apoptosis. Moreover, TSC1 deficiency attenuates tumor growth in a xenograft mouse model. Our study reveals a novel role for TSC1 in securing homeostasis between MYC and mTORC1 that is required for cell survival and tumor maintenance in Burkitt's lymphoma. The study identifies TSC1/2 inhibition and/or mTORC1 hyperactivation as a novel therapeutic strategy for MYC-driven cancers.


Asunto(s)
Linfoma de Burkitt/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteína 1 del Complejo de la Esclerosis Tuberosa/metabolismo , Proteína 2 del Complejo de la Esclerosis Tuberosa/metabolismo , Animales , Linfoma de Burkitt/genética , Linfoma de Burkitt/patología , Células HEK293 , Xenoinjertos , Humanos , Células MCF-7 , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Ratones , Ratones Endogámicos NOD , Ratones SCID , MicroARNs/genética , MicroARNs/metabolismo , Trasplante de Neoplasias , Proteínas Proto-Oncogénicas c-myc/genética , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Proteína 1 del Complejo de la Esclerosis Tuberosa/genética , Proteína 2 del Complejo de la Esclerosis Tuberosa/genética
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