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1.
Stem Cells ; 42(7): 581-592, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38655883

RESUMO

Fully grown oocytes have the natural ability to transform 2 terminally differentiated gametes into a totipotent zygote representing the acquisition of totipotency. This process wholly depends on maternal-effect factors (MFs). MFs stored in the eggs are therefore likely to be able to induce cellular reprogramming to a totipotency state. Here we report the generation of totipotent-like stem cells from mESCs using 4MFs Hsf1, Zar1, Padi6, and Npm2, designated as MFiTLSCs. MFiTLSCs exhibited a unique and inherent capability to differentiate into embryonic and extraembryonic derivatives. Transcriptomic analysis revealed that MFiTLSCs are enriched with 2-cell-specific genes that appear to synergistically induce a transcriptional repressive state, in that parental genomes are remodeled to a poised transcriptional repression state while totipotency is established following fertilization. This method to derive MFiTLSCs could help advance the understanding of fate determinations of totipotent stem cells in a physiological context and establish a foundation for the development of oocyte biology-based reprogramming technology.


Assuntos
Células-Tronco Totipotentes , Animais , Camundongos , Células-Tronco Totipotentes/metabolismo , Células-Tronco Totipotentes/citologia , Diferenciação Celular/genética , Feminino , Reprogramação Celular/genética , Oócitos/metabolismo , Oócitos/citologia
2.
Cell Commun Signal ; 22(1): 362, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39010102

RESUMO

Dihydroorotase (DHOase) is the third enzyme in the six enzymatic reaction steps of the endogenous pyrimidine nucleotide de novo biosynthesis pathway, which is a metabolic pathway conserved in both bacteria and eukaryotes. However, research on the biological function of DHOase in plant pathogenic fungi is very limited. In this study, we identified and named MoPyr4, a homologous protein of Saccharomyces cerevisiae DHOase Ura4, in the rice blast fungus Magnaporthe oryzae and investigated its ability to regulate fungal growth, pathogenicity, and autophagy. Deletion of MoPYR4 led to defects in growth, conidiation, appressorium formation, the transfer and degradation of glycogen and lipid droplets, appressorium turgor accumulation, and invasive hypha expansion in M. oryzae, which eventually resulted in weakened fungal pathogenicity. Long-term replenishment of exogenous uridine-5'-phosphate (UMP) can effectively restore the phenotype and virulence of the ΔMopyr4 mutant. Further study revealed that MoPyr4 also participated in the regulation of the Pmk1-MAPK signaling pathway, co-localized with peroxisomes for the oxidative stress response, and was involved in the regulation of the Osm1-MAPK signaling pathway in response to hyperosmotic stress. In addition, MoPyr4 interacted with MoAtg5, the core protein involved in autophagy, and positively regulated autophagic degradation. Taken together, our results suggested that MoPyr4 for UMP biosynthesis was crucial for the development and pathogenicity of M. oryzae. We also revealed that MoPyr4 played an essential role in the external stress response and pathogenic mechanism through participation in the Pmk1-MAPK signaling pathway, peroxisome-related oxidative stress response mechanism, the Osm1-MAPK signaling pathway and the autophagy pathway.


Assuntos
Autofagia , Proteínas Fúngicas , Oryza , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Oryza/microbiologia , Virulência/genética , Peroxissomos/metabolismo , Doenças das Plantas/microbiologia , Ascomicetos/patogenicidade , Ascomicetos/genética , Ascomicetos/enzimologia , Sistema de Sinalização das MAP Quinases , Estresse Oxidativo
3.
Cell Commun Signal ; 22(1): 222, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594767

RESUMO

Csn5 is subunit 5 of the COP9 signalosome (CSN), but the mechanism by which it strictly controls the pathogenicity of pathogenic fungi through autophagy remains unclear. Here, we found that Csn5 deficiency attenuated pathogenicity and enhanced autophagy in Magnaporthe oryzae. MoCSN5 knockout led to overubiquitination and overdegradation of MoTor (the core protein of the TORC1 complex [target of rapamycin]) thereby promoted autophagy. In addition, we identified MoCsn5 as a new interactor of MoAtg6. Atg6 was found to be ubiquitinated through linkage with lysine 48 (K48) in cells, which is necessary for infection-associated autophagy in pathogenic fungi. K48-ubiquitination of Atg6 enhanced its degradation and thereby inhibited autophagic activity. Our experimental results indicated that MoCsn5 promoted K48-ubiquitination of MoAtg6, which reduced the MoAtg6 protein content and thus inhibited autophagy. Aberrant ubiquitination and autophagy in ΔMocsn5 led to pleiotropic defects in the growth, development, stress resistance, and pathogenicity of M. oryzae. In summary, our study revealed a novel mechanism by which Csn5 regulates autophagy and pathogenicity in rice blast fungus through ubiquitination.


Assuntos
Ascomicetos , Virulência , Proteínas , Ubiquitinação , Autofagia
4.
Mol Ther ; 31(5): 1207-1224, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-36245129

RESUMO

Developing strategies toward safe and effective drug delivery into the central nervous system (CNS) with improved targeting abilities and reduced off-target effects is crucial. CNS-targeted drug carriers made of synthetic molecules raise concerns about their biodegradation, clearance, immune responses, and neurotoxicity. Cell-derived nanovesicles (CDNs) have recently been applied in CNS-targeted drug delivery, because of their intrinsic stability, biocompatibility, inherent homing capability, and the ability to penetrate through biological barriers, including the blood-brain barrier. Among these CDNs, extracellular vesicles and exosomes are the most studied because their surface can be engineered and modified to cater to brain targeting. In this review, we focus on the application of CDNs in brain-targeted drug delivery to treat neurological diseases. We cover recently developed methods of exosome derivation and engineering, including exosome-like particles, hybrid exosomes, exosome-associated adeno-associated viruses, and envelope protein nanocages. Finally, we discuss the limitations and project the future development of the CDN-based brain-targeted delivery systems, and conclude that engineered CDNs hold great potential in the treatment of neurological diseases.


Assuntos
Exossomos , Vesículas Extracelulares , Sistemas de Liberação de Medicamentos/métodos , Encéfalo , Exossomos/metabolismo , Barreira Hematoencefálica/metabolismo
5.
Acta Derm Venereol ; 104: adv22146, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38738772

RESUMO

There are no standard treatment guidelines for hidradenocarcinoma, and the immune microenvironment and genomic data are very limited. Thus, in this study the immune microenvironment and genomic indicators in hidradenocarcinoma was investigated, and immunotherapy for hidradenocarcinoma was initially explored. Forty-seven hidradenocarcinoma patients were retrospectively collected. Immunohistochemical staining was performed to identify CD3/CD8+ T cells and programmed death ligand-1 expression. In total, 89.4% and 10.6% of samples had Immunoscores of 0-25% and 25-70%. Tumour proportion score distribution was as follows: tumour proportion score < 1% in 72.4%, 1-5% in 17.0%, and > 5% in 10.6%. Combined positive score distribution was as follows: combined positive score < 1 in 63.8%, 1-5 in 14.9%, and > 5 in 21.3%. Next-generation sequencing revealed that TP53 (33%), PI3KCA (22%), and ERBB3 (22%) were the most frequently mutated genes. The PI3K-Akt signalling pathway, growth, and MAPK signalling pathways were significantly enriched. Five patients had a low TMB (< 10 muts/Mb), and 9 patients had MSS. Three patients treated with immune combined with chemotherapy achieved significant tumour regression, and the progression-free survival was 28.8 months. In conclusion, the hidradenocarcinoma immune microenvironment tends to be noninflammatory. Evidence-based targets for targeted therapy are lacking. Immunotherapy combined with chemotherapy may be better for most advanced hidradenocarcinoma patients with a noninflammatory microenvironment.


Assuntos
Biomarcadores Tumorais , Neoplasias das Glândulas Sudoríparas , Microambiente Tumoral , Humanos , Estudos Retrospectivos , Neoplasias das Glândulas Sudoríparas/genética , Neoplasias das Glândulas Sudoríparas/patologia , Neoplasias das Glândulas Sudoríparas/terapia , Neoplasias das Glândulas Sudoríparas/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/análise , Mutação , Resultado do Tratamento , Linfócitos do Interstício Tumoral/imunologia , Antígeno B7-H1 , Imunoterapia/métodos , Adulto Jovem , Antineoplásicos Imunológicos/uso terapêutico
6.
Eur Child Adolesc Psychiatry ; 33(7): 2387-2396, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38147111

RESUMO

Schizophrenia and autism spectrum disorders (ASD) were considered as two neurodevelopmental disorders and had shared clinical features. we hypothesized that they have some common atypical brain functions and the purpose of this study was to explored the shared brain spontaneous activity strength alterations in early onset schizophrenia (EOS) and ASD in the children and adolescents with a multi-center large-sample study. A total of 171 EOS patients (aged 14.25 ± 1.87), 188 ASD patients (aged 9.52 ± 5.13), and 107 healthy controls (aged 11.52 ± 2.82) had scanned with Resting-fMRI and analyzed surface-based amplitude of low-frequency fluctuations (ALFF). Results showed that both EOS and ASD had hypoactivity in the primary sensorimotor regions (bilateral primary and early visual cortex, left ventral visual stream, left primary auditory cortex) and hyperactivity in the high-order transmodal regions (bilateral SFL, bilateral DLPFC, right frontal eye fields), and bilateral thalamus. EOS had more severe abnormality than ASD. This study revealed shared functional abnormalities in the primary sensorimotor regions and the high-order transmodal regions in EOS and ASD, which provided neuroimaging evidence of common changes in EOS and ASD, and may help with better early recognition and precise treatment for EOS and ASD.


Assuntos
Transtorno do Espectro Autista , Imageamento por Ressonância Magnética , Esquizofrenia , Humanos , Transtorno do Espectro Autista/fisiopatologia , Transtorno do Espectro Autista/diagnóstico por imagem , Masculino , Feminino , Adolescente , Criança , Esquizofrenia/fisiopatologia , Esquizofrenia/diagnóstico por imagem , Mapeamento Encefálico , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem
7.
Nano Lett ; 23(10): 4326-4333, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37130058

RESUMO

Escherichia coli K1 (EC-K1) can bypass the blood-brain barrier (BBB) and cause meningitis. Excitingly, we find the "dead EC-K1" can safely penetrate the BBB because they retain the intact structure and chemotaxis of the live EC-K1, while losing their pathogenicity. Based on this, we develop a safe "dead EC-K1"-based drug delivery system, in which EC-K1 engulf the maltodextrin (MD)-modified therapeutics through the bacteria-specific MD transporter pathway, followed by the inactivation via UV irradiation. We demonstrate that the dead bacteria could carry therapeutics (e.g., indocyanine green (ICG)) and together bypass the BBB after intravenous injection into the mice, delivering ∼3.0-fold higher doses into the brain than free ICG under the same conditions. What is more, all mice remain healthy even after 14 days of intravenous injection of ∼109 CFU of inactive bacteria. As a proof of concept, we demonstrate the developed strategy enables the therapy of bacterial meningitis and glioblastoma in mice.


Assuntos
Barreira Hematoencefálica , Meningites Bacterianas , Animais , Camundongos , Escherichia coli , Encéfalo , Meningites Bacterianas/microbiologia , Virulência
8.
Ann Surg ; 278(1): e68-e79, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35781511

RESUMO

OBJECTIVE: To develop an imaging-derived biomarker for prediction of overall survival (OS) of pancreatic cancer by analyzing preoperative multiphase contrast-enhanced computed topography (CECT) using deep learning. BACKGROUND: Exploiting prognostic biomarkers for guiding neoadjuvant and adjuvant treatment decisions may potentially improve outcomes in patients with resectable pancreatic cancer. METHODS: This multicenter, retrospective study included 1516 patients with resected pancreatic ductal adenocarcinoma (PDAC) from 5 centers located in China. The discovery cohort (n=763), which included preoperative multiphase CECT scans and OS data from 2 centers, was used to construct a fully automated imaging-derived prognostic biomarker-DeepCT-PDAC-by training scalable deep segmentation and prognostic models (via self-learning) to comprehensively model the tumor-anatomy spatial relations and their appearance dynamics in multiphase CECT for OS prediction. The marker was independently tested using internal (n=574) and external validation cohorts (n=179, 3 centers) to evaluate its performance, robustness, and clinical usefulness. RESULTS: Preoperatively, DeepCT-PDAC was the strongest predictor of OS in both internal and external validation cohorts [hazard ratio (HR) for high versus low risk 2.03, 95% confidence interval (CI): 1.50-2.75; HR: 2.47, CI: 1.35-4.53] in a multivariable analysis. Postoperatively, DeepCT-PDAC remained significant in both cohorts (HR: 2.49, CI: 1.89-3.28; HR: 2.15, CI: 1.14-4.05) after adjustment for potential confounders. For margin-negative patients, adjuvant chemoradiotherapy was associated with improved OS in the subgroup with DeepCT-PDAC low risk (HR: 0.35, CI: 0.19-0.64), but did not affect OS in the subgroup with high risk. CONCLUSIONS: Deep learning-based CT imaging-derived biomarker enabled the objective and unbiased OS prediction for patients with resectable PDAC. This marker is applicable across hospitals, imaging protocols, and treatments, and has the potential to tailor neoadjuvant and adjuvant treatments at the individual level.


Assuntos
Carcinoma Ductal Pancreático , Aprendizado Profundo , Neoplasias Pancreáticas , Humanos , Estudos Retrospectivos , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia , Prognóstico , Neoplasias Pancreáticas
9.
Lancet ; 400(10363): 1585-1596, 2022 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-36341753

RESUMO

BACKGROUND: The optimum systolic blood pressure after endovascular thrombectomy for acute ischaemic stroke is uncertain. We aimed to compare the safety and efficacy of blood pressure lowering treatment according to more intensive versus less intensive treatment targets in patients with elevated blood pressure after reperfusion with endovascular treatment. METHODS: We conducted an open-label, blinded-endpoint, randomised controlled trial at 44 tertiary-level hospitals in China. Eligible patients (aged ≥18 years) had persistently elevated systolic blood pressure (≥140 mm Hg for >10 min) following successful reperfusion with endovascular thrombectomy for acute ischaemic stroke from any intracranial large-vessel occlusion. Patients were randomly assigned (1:1, by a central, web-based program with a minimisation algorithm) to more intensive treatment (systolic blood pressure target <120 mm Hg) or less intensive treatment (target 140-180 mm Hg) to be achieved within 1 h and sustained for 72 h. The primary efficacy outcome was functional recovery, assessed according to the distribution in scores on the modified Rankin scale (range 0 [no symptoms] to 6 [death]) at 90 days. Analyses were done according to the modified intention-to-treat principle. Efficacy analyses were performed with proportional odds logistic regression with adjustment for treatment allocation as a fixed effect, site as a random effect, and baseline prognostic factors, and included all randomly assigned patients who provided consent and had available data for the primary outcome. The safety analysis included all randomly assigned patients. The treatment effects were expressed as odds ratios (ORs). This trial is registered at ClinicalTrials.gov, NCT04140110, and the Chinese Clinical Trial Registry, 1900027785; recruitment has stopped at all participating centres. FINDINGS: Between July 20, 2020, and March 7, 2022, 821 patients were randomly assigned. The trial was stopped after review of the outcome data on June 22, 2022, due to persistent efficacy and safety concerns. 407 participants were assigned to the more intensive treatment group and 409 to the less intensive treatment group, of whom 404 patients in the more intensive treatment group and 406 patients in the less intensive treatment group had primary outcome data available. The likelihood of poor functional outcome was greater in the more intensive treatment group than the less intensive treatment group (common OR 1·37 [95% CI 1·07-1·76]). Compared with the less intensive treatment group, the more intensive treatment group had more early neurological deterioration (common OR 1·53 [95% 1·18-1·97]) and major disability at 90 days (OR 2·07 [95% CI 1·47-2·93]) but there were no significant differences in symptomatic intracerebral haemorrhage. There were no significant differences in serious adverse events or mortality between groups. INTERPRETATION: Intensive control of systolic blood pressure to lower than 120 mm Hg should be avoided to prevent compromising the functional recovery of patients who have received endovascular thrombectomy for acute ischaemic stroke due to intracranial large-vessel occlusion. FUNDING: The Shanghai Hospital Development Center; National Health and Medical Research Council of Australia; Medical Research Futures Fund of Australia; China Stroke Prevention; Shanghai Changhai Hospital, Science and Technology Commission of Shanghai Municipality; Takeda China; Hasten Biopharmaceutic; Genesis Medtech; Penumbra.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Adolescente , Adulto , Isquemia Encefálica/tratamento farmacológico , Acidente Vascular Cerebral/terapia , Pressão Sanguínea/fisiologia , Resultado do Tratamento , China/epidemiologia , Trombectomia/efeitos adversos , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/cirurgia
10.
N Engl J Med ; 382(21): 1981-1993, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32374959

RESUMO

BACKGROUND: In acute ischemic stroke, there is uncertainty regarding the benefit and risk of administering intravenous alteplase before endovascular thrombectomy. METHODS: We conducted a trial at 41 academic tertiary care centers in China to evaluate endovascular thrombectomy with or without intravenous alteplase in patients with acute ischemic stroke. Patients with acute ischemic stroke from large-vessel occlusion in the anterior circulation were randomly assigned in a 1:1 ratio to undergo endovascular thrombectomy alone (thrombectomy-alone group) or endovascular thrombectomy preceded by intravenous alteplase, at a dose of 0.9 mg per kilogram of body weight, administered within 4.5 hours after symptom onset (combination-therapy group). The primary analysis for noninferiority assessed the between-group difference in the distribution of the modified Rankin scale scores (range, 0 [no symptoms] to 6 [death]) at 90 days on the basis of a lower boundary of the 95% confidence interval of the adjusted common odds ratio equal to or larger than 0.8. We assessed various secondary outcomes, including death and reperfusion of the ischemic area. RESULTS: Of 1586 patients screened, 656 were enrolled, with 327 patients assigned to the thrombectomy-alone group and 329 assigned to the combination-therapy group. Endovascular thrombectomy alone was noninferior to combined intravenous alteplase and endovascular thrombectomy with regard to the primary outcome (adjusted common odds ratio, 1.07; 95% confidence interval, 0.81 to 1.40; P = 0.04 for noninferiority) but was associated with lower percentages of patients with successful reperfusion before thrombectomy (2.4% vs. 7.0%) and overall successful reperfusion (79.4% vs. 84.5%). Mortality at 90 days was 17.7% in the thrombectomy-alone group and 18.8% in the combination-therapy group. CONCLUSIONS: In Chinese patients with acute ischemic stroke from large-vessel occlusion, endovascular thrombectomy alone was noninferior with regard to functional outcome, within a 20% margin of confidence, to endovascular thrombectomy preceded by intravenous alteplase administered within 4.5 hours after symptom onset. (Funded by the Stroke Prevention Project of the National Health Commission of the People's Republic of China and the Wu Jieping Medical Foundation; DIRECT-MT ClinicalTrials.gov number, NCT03469206.).


Assuntos
Fibrinolíticos/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Ativador de Plasminogênio Tecidual/uso terapêutico , Idoso , Hemorragia Cerebral/etiologia , China , Terapia Combinada , Intervalos de Confiança , Procedimentos Endovasculares , Feminino , Fibrinolíticos/efeitos adversos , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Reperfusão/métodos , Trombectomia/efeitos adversos , Tempo para o Tratamento , Ativador de Plasminogênio Tecidual/efeitos adversos , Resultado do Tratamento
11.
Radiology ; 306(1): 160-169, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36066369

RESUMO

Background Although deep learning has brought revolutionary changes in health care, reliance on manually selected cross-sectional images and segmentation remain methodological barriers. Purpose To develop and validate an automated preoperative artificial intelligence (AI) algorithm for tumor and lymph node (LN) segmentation with CT imaging for prediction of LN metastasis in patients with pancreatic ductal adenocarcinoma (PDAC). Materials and Methods In this retrospective study, patients with surgically resected, pathologically confirmed PDAC underwent multidetector CT from January 2015 to April 2020. Three models were developed, including an AI model, a clinical model, and a radiomics model. CT-determined LN metastasis was diagnosed by radiologists. Multivariable logistic regression analysis was conducted to develop the clinical and radiomics models. The performance of the models was determined on the basis of their discrimination and clinical utility. Kaplan-Meier curves, the log-rank test, or Cox regression were used for survival analysis. Results Overall, 734 patients (mean age, 62 years ± 9 [SD]; 453 men) were evaluated. All patients were split into training (n = 545) and validation (n = 189) sets. Patients who had LN metastasis (LN-positive group) accounted for 340 of 734 (46%) patients. In the training set, the AI model showed the highest performance (area under the receiver operating characteristic curve [AUC], 0.91) in the prediction of LN metastasis, whereas the radiologists and the clinical and radiomics models had AUCs of 0.58, 0.76, and 0.71, respectively. In the validation set, the AI model showed the highest performance (AUC, 0.92) in the prediction of LN metastasis, whereas the radiologists and the clinical and radiomics models had AUCs of 0.65, 0.77, and 0.68, respectively (P < .001). AI model-predicted positive LN metastasis was associated with worse survival (hazard ratio, 1.46; 95% CI: 1.13, 1.89; P = .004). Conclusion An artificial intelligence model outperformed radiologists and clinical and radiomics models for prediction of lymph node metastasis at CT in patients with pancreatic ductal adenocarcinoma. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Chu and Fishman in this issue.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Masculino , Humanos , Pessoa de Meia-Idade , Metástase Linfática , Estudos Retrospectivos , Inteligência Artificial , Tomografia Computadorizada Multidetectores , Linfonodos , Neoplasias Pancreáticas
12.
J Magn Reson Imaging ; 58(1): 223-231, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36373955

RESUMO

BACKGROUND: Gradient nonlinearity (GNL) introduces spatial nonuniformity bias in apparent diffusion coefficient (ADC) measurements, especially at large offsets from the magnet isocenter. PURPOSE: To investigate the effects of GNL in abdominal ADC measurements and to develop an ADC bias correction procedure. STUDY TYPE: Retrospective. PHANTOM/POPULATION: Two homemade ultrapure water phantoms/25 patients with histologically confirmed pancreatic ductal adenocarcinoma (PDAC). FIELD STRENGTH/SEQUENCE: A 3.0 T/diffusion-weighted imaging (DWI) with single-shot echo-planar imaging sequence. ASSESSMENT: ADC bias was computed in the three orthogonal directions at different offset locations. The spatial-dependent correctors of ADC bias were generated from the ADCs of phantom 1. The ADCs were estimated before and after corrections for the phantom 1 with both the proposed approach and the theoretical GNL correction method. For the patients, ADCs were measured in abdominal tissues including left and right liver lobes, PDAC, spleen, bilateral kidneys, and bilateral paraspinal muscles. STATISTICAL TEST: Friedman tests and Wilcoxon tests. RESULTS: The ADC bias measured by phantom 1 was 9.7% and 12.6% higher in the right-left and anterior-posterior directions and 9.2% lower in the superior-inferior direction at the 150 mm offsets from the magnetic isocenter. The corrected vs. the uncorrected ADCs measurements (median: 2.20 × 10-3  mm2 /sec for both the proposed method and the theoretical GNL method vs. 2.31 × 10-3  mm2 /sec, respectively) and their relative ADC errors (0.014, 0.016, and 0.054, respectively) were lower in the phantom 1. The relative ADC errors substantially decreased after correction in the phantom 2 (median: 0.048 and -0.008, respectively). The ADCs of all the abdominal tissues were lower after correction except for the left liver lobes (P = 0.13). DATA CONCLUSION: GNL bias in abdominal ADC can be measured by a DWI phantom. The proposed correction procedure was successfully applied for the bias correction in abdominal ADC. EVIDENCE LEVEL: 3. TECHNICAL EFFICACY: Stage 1.


Assuntos
Abdome , Cavidade Abdominal , Humanos , Estudos Retrospectivos , Reprodutibilidade dos Testes , Abdome/diagnóstico por imagem , Fígado/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Imagens de Fantasmas
13.
Eur Radiol ; 33(5): 3580-3591, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36884086

RESUMO

OBJECTIVES: To develop and validate a radiomics nomogram based on a fully automated pancreas segmentation to assess pancreatic exocrine function. Furthermore, we aimed to compare the performance of the radiomics nomogram with the pancreatic flow output rate (PFR) and conclude on the replacement of secretin-enhanced magnetic resonance cholangiopancreatography (S-MRCP) by the radiomics nomogram for pancreatic exocrine function assessment. METHODS: All participants underwent S-MRCP between April 2011 and December 2014 in this retrospective study. PFR was quantified using S-MRCP. Participants were divided into normal and pancreatic exocrine insufficiency (PEI) groups using the cut-off of 200 µg/L of fecal elastase-1. Two prediction models were developed including the clinical and non-enhanced T1-weighted imaging radiomics model. A multivariate logistic regression analysis was conducted to develop the prediction models. The models' performances were determined based on their discrimination, calibration, and clinical utility. RESULTS: A total of 159 participants (mean age [Formula: see text] standard deviation, 45 years [Formula: see text] 14;119 men) included 85 normal and 74 PEI. All the participants were divided into a training set comprising 119 consecutive patients and an independent validation set comprising 40 consecutive patients. The radiomics score was an independent risk factor for PEI (odds ratio = 11.69; p < 0.001). In the validation set, the radiomics nomogram exhibited the highest performance (AUC, 0.92) in PEI prediction, whereas the clinical nomogram and PFR had AUCs of 0.79 and 0.78, respectively. CONCLUSION: The radiomics nomogram accurately predicted pancreatic exocrine function and outperformed pancreatic flow output rate on S-MRCP in patients with chronic pancreatitis. KEY POINTS: • The clinical nomogram exhibited moderate performance in diagnosing pancreatic exocrine insufficiency. • The radiomics score was an independent risk factor for pancreatic exocrine insufficiency, and every point rise in the rad-score was associated with an 11.69-fold increase in pancreatic exocrine insufficiency risk. • The radiomics nomogram accurately predicted pancreatic exocrine function and outperformed the clinical model and pancreatic flow output rate quantified by secretin-enhanced magnetic resonance cholangiopancreatography on MRI in patients with chronic pancreatitis.


Assuntos
Insuficiência Pancreática Exócrina , Pancreatite Crônica , Humanos , Masculino , Pessoa de Meia-Idade , Colangiopancreatografia por Ressonância Magnética/métodos , Insuficiência Pancreática Exócrina/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Pancreatite Crônica/diagnóstico por imagem , Estudos Retrospectivos , Secretina , Feminino
14.
Eur Radiol ; 33(2): 1353-1363, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35997838

RESUMO

OBJECTIVE: To investigate the feasibility of b-value threshold (bThreshold) map in preoperative evaluation of tumor budding (TB) in patients with locally advanced rectal cancer (LARC). METHODS: Patients with LARC were enrolled and underwent diffusion-weighted imaging (DWI). Contrast-to-noise ratio (CNR) between the lesions and normal tissues was assessed using DWI and bThreshold maps. TB was counted and scored using hematoxylin and eosin staining. Reproducibility for the apparent diffusion coefficient (ADC), bThreshold values, and region-of-interest (ROI) sizes were compared. Differences in ADC and bThreshold values with low-intermediate and high TB grades and the correlations between mean ADC and bThreshold values with TB categories were analyzed. Diagnostic performance of ADC and bThreshold values was assessed using area under the curve (AUC) and decision curve analysis. RESULTS: Fifty-one patients were evaluated. The CNR on bThreshold maps was significantly higher than that on DW images (9.807 ± 4.811 vs 7.779 ± 3.508, p = 0.005). Reproducibility was excellent for the ADC (ICC 0.933; CV 8.807%), bThreshold values (ICC 0.958; CV 7.399%), and ROI sizes (ICC 0.934; CV 8.425%). Significant negative correlations were observed between mean ADC values and TB grades and positive correlations were observed between mean bThreshold values and TB grades (p < 0.05). bThreshold maps showed better diagnostic performance than ADC maps (AUC, 0.914 vs 0.726; p = 0.048). CONCLUSIONS: In LARC patients, bThreshold values could distinguish different TB grades better than ADC values, and bThreshold maps may be a preoperative, non-invasive approach to evaluate TB grades. KEY POINTS: • Compared with diffusion-weighted images, bThreshold maps improved visualization and detection of rectal tumors. • Agreement and diagnostic performance of bThreshold values are superior to apparent diffusion coefficient in assessing tumor budding grades in patients with locally advanced rectal cancer. • bThreshold maps could be used to evaluate tumor budding grades non-invasively before operation.


Assuntos
Adenocarcinoma , Segunda Neoplasia Primária , Neoplasias Retais , Humanos , Reprodutibilidade dos Testes , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Reto/patologia , Adenocarcinoma/diagnóstico por imagem
15.
Int J Colorectal Dis ; 38(1): 40, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36790595

RESUMO

PURPOSE: To measure the diagnostic performance of modified MRI-based split scar sign (mrSSS) score for the prediction of pathological complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT) for patients with rectal cancer. METHODS: The modified MRI-based split scar sign (mrSSS) score, which consists of T2-weighted images (T2WI)-based score and diffusion-weighted images (DWI)-based score. The sensitivity, specificity, and accuracy of modified mrSSS score, endoscopic gross type, and MRI-based tumor regression grading (mrTRG) score, in the prediction of pCR, were compared. The prognostic value of the modified mrSSS score was also studied. RESULTS: A total of 189 patients were included in the study. The Kendall's coefficient of interobserver concordance of modified mrSSS score, T2WI -based score, and DWI-based score were 0.899, 0.890, and 0.789 respectively. And the maximum and minimum k value of the modified mrSSS score was 0.797 (0.742-0.853) and 0.562 (0.490-0.634). The sensitivity, specificity, and accuracy of prediction of pCR were 0.66, 0.97, and 0.90 for modified mrSSS score; 0.37, 0.89, and 0.78 for endoscopic gross type (scar); and 0.24, 0.92, and 0.77 for mrTRG score (mrTRG = 1). The modified mrSSS score had significantly higher sensitivity than the endoscopic gross type and the mrTRG score in predicting pCR. Patients with lower modified mrSSS scores had significantly longer disease-free survival (P < 0.05). CONCLUSION: The modified mrSSS score showed satisfactory interobserver agreement and higher sensitivity in predicting pCR after nCRT in patients with rectal cancer. The modified mrSSS score is also a predictor of disease-free survival.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais , Humanos , Terapia Neoadjuvante/métodos , Cicatriz/patologia , Imageamento por Ressonância Magnética/métodos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/terapia , Prognóstico , Quimiorradioterapia/métodos , Resultado do Tratamento , Estudos Retrospectivos , Imagem de Difusão por Ressonância Magnética/métodos
16.
Int J Mol Sci ; 24(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37298247

RESUMO

Calcineurin, a key regulator of the calcium signaling pathway, is involved in calcium signal transduction and calcium ion homeostasis. Magnaporthe oryzae is a devastating filamentous phytopathogenic fungus in rice, yet little is known about the function of the calcium signaling system. Here, we identified a novel calcineurin regulatory-subunit-binding protein, MoCbp7, which is highly conserved in filamentous fungi and was found to localize in the cytoplasm. Phenotypic analysis of the MoCBP7 gene deletion mutant (ΔMocbp7) showed that MoCbp7 influenced the growth, conidiation, appressorium formation, invasive growth, and virulence of M. oryzae. Some calcium-signaling-related genes, such as YVC1, VCX1, and RCN1, are expressed in a calcineurin/MoCbp7-dependent manner. Furthermore, MoCbp7 synergizes with calcineurin to regulate endoplasmic reticulum homeostasis. Our research indicated that M. oryzae may have evolved a new calcium signaling regulatory network to adapt to its environment compared to the fungal model organism Saccharomyces cerevisiae.


Assuntos
Magnaporthe , Oryza , Virulência/genética , Calcineurina/genética , Calcineurina/metabolismo , Proteínas de Transporte/metabolismo , Sinalização do Cálcio , Cálcio/metabolismo , Magnaporthe/fisiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Oryza/metabolismo , Doenças das Plantas/microbiologia , Esporos Fúngicos
17.
Molecules ; 28(18)2023 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-37764443

RESUMO

In fungi, the methylcitrate cycle converts cytotoxic propionyl-coenzyme A (CoA) to pyruvate, which enters gluconeogenesis. The glyoxylate cycle converts acetyl-CoA to succinate, which enters gluconeogenesis. The tricarboxylic acid cycle is a central carbon metabolic pathway that connects the methylcitrate cycle, the glyoxylate cycle, and other metabolisms for lipids, carbohydrates, and amino acids. Fungal citrate synthase and 2-methylcitrate synthase as well as isocitrate lyase and 2-methylisocitrate lyase, each evolved from a common ancestral protein. Impairment of the methylcitrate cycle leads to the accumulation of toxic intermediates such as propionyl-CoA, 2-methylcitrate, and 2-methylisocitrate in fungal cells, which in turn inhibits the activity of many enzymes such as dehydrogenases and remodels cellular carbon metabolic processes. The methylcitrate cycle and the glyoxylate cycle synergistically regulate carbon source utilization as well as fungal growth, development, and pathogenic process in pathogenic fungi.


Assuntos
Ciclo do Ácido Cítrico , Fungos , Acetilcoenzima A , Fungos/metabolismo , Carbono/metabolismo , Glioxilatos/metabolismo
18.
Stroke ; 53(5): 1674-1681, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34872341

RESUMO

BACKGROUND: Prior studies have investigated the clinical and imaging factors for hemorrhagic transformation (HT), especially symptomatic intracranial hemorrhage (sICH); however, whether alteplase increases the risk of HT after endovascular thrombectomy (EVT) is unknown. This study aimed to assess clinical and imaging features associated with HT, sICH, and parenchymal hematoma (PH) in patients with acute ischemic stroke after EVT, with and without intravenous alteplase in DIRECT-MT (Direct Intraarterial Thrombectomy to Revascularize Acute Ischemic Stroke Patients with Large Vessel Occlusion Efficiently in Chinese Tertiary Hospitals: a Multicenter Randomized Clinical Trial). METHODS: The DIRECT-MT trial is a randomized trial of EVT alone versus intravenous thrombolysis combined with EVT. HT, sICH, and PH was evaluated on follow-up computed tomography. Multivariable ordinal logistic regression analysis was used to test the association of stepwise selected determinants with HT, sICH, and PH. RESULTS: In total, 633 patients were analyzed; 261 (41.2%) had HT; 34 (5.4%) had sICH; and 85 (13.4%) had PH. The median age was 69, and 56.7% were men. The median National Institutes of Health Stroke Scale score was 18, and 320 patients were in combination-therapy group. Symptomatic intracranial hemorrhage was associated with higher baseline National Institutes of Health Stroke Scale score (adjusted odds ratio [OR], 1.06 [95% CI, 1.10-1.12]) and higher glucose level at hospital arrival (adjusted OR, 1.14 [95% CI, 1.00-1.29]). No association was found between alteplase treatment and HT, sICH, or PH. The independent predictor of sICH was higher baseline National Institutes of Health Stroke Scale score (adjusted OR, 1.09 [95% CI, 1.01-1.18]) in EVT alone group, and history of anticoagulant drugs (adjusted OR, 3.75 [95% CI, 1.07-13.06]), higher glucose level at hospital arrival (adjusted OR, 1.19 [95% CI, 1.03-1.38]), >3 passes of device (adjusted OR, 4.42 [95% CI, 1.36-14.32]) in combination-therapy group. CONCLUSIONS: In DIRECT-MT, independent predictors of sICH were baseline National Institutes of Health Stroke Scale score and glucose level at hospital arrival. Alteplase treatment did not increase the risk of HT, sICH, or PH after EVT. The independent predictor of sICH was different in EVT alone group and combination-therapy group. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03469206.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Feminino , Glucose/uso terapêutico , Humanos , Hemorragias Intracranianas/diagnóstico por imagem , Hemorragias Intracranianas/epidemiologia , Hemorragias Intracranianas/etiologia , Masculino , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Trombectomia/efeitos adversos , Ativador de Plasminogênio Tecidual , Estados Unidos
19.
Environ Microbiol ; 24(3): 1653-1671, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35229430

RESUMO

The development and pathogenicity of the fungus Magnaporthe oryzae, the causal agent of destructive rice blast disease, require it to perceive external environmental signals. Opy2, an overproduction-induced pheromone-resistant protein 2, is a crucial protein for sensing external signals in Saccharomyces cerevisiae. However, the biological functions of the homologue of Opy2 in M. oryzae are unclear. In this study, we identified that MoOPY2 is involved in fungal development, pathogenicity, and autophagy in M. oryzae. Deletion of MoOPY2 resulted in pleiotropic defects in hyphal growth, conidiation, germ tube extension, appressorium formation, appressorium turgor generation, and invasive growth, therefore leading to attenuated pathogenicity. Furthermore, MoOpy2 participates in the Osm1 MAPK pathway and the Mps1 MAPK pathway by interacting with the adaptor protein Mst50. The interaction sites of Mst50 and MoOpy2 colocalized with the autophagic marker protein MoAtg8 in the preautophagosomal structure sites (PAS). Notably, the ΔMoopy2 mutant caused cumulative MoAtg8 lipidation and rapid GFP-MoAtg8 degradation in response to nitrogen starvation, showing that MoOpy2 is involved in the negative regulation of autophagy activity. Taken together, our study revealed that MoOpy2 of M. oryzae plays an essential role in the orchestration of fungal development, appressorium penetration, autophagy and pathogenesis.


Assuntos
Magnaporthe , Oryza , Ascomicetos , Autofagia/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Magnaporthe/metabolismo , Oryza/microbiologia , Doenças das Plantas/microbiologia , Esporos Fúngicos/metabolismo , Virulência/genética
20.
Environ Microbiol ; 24(3): 1076-1092, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34472190

RESUMO

Magnaporthe oryzae is an important plant pathogen that causes rice blast. Hse1 and Vps27 are components of ESCRT-0 involved in the multivesicular body (MVB) sorting pathway and biogenesis. To date, the biological functions of ESCRT-0 in M. oryzae have not been determined. In this study, we identified and characterized Hse1 and Vps27 in M. oryzae. Disruption of MoHse1 and MoVps27 caused pleiotropic defects in growth, conidiation, sexual development and pathogenicity, thereby resulting in loss of virulence in rice and barley leaves. Disruption of MoHse1 and MoVps27 triggered increased lipidation of MoAtg8 and degradation of GFP-MoAtg8, indicating that ESCRT-0 is involved in the regulation of autophagy. ESCRT-0 was determined to interact with coat protein complex II (COPII), a regulator functioning in homeostasis of the endoplasmic reticulum (ER homeostasis), and disruption of MoHse1 and MoVps27 also blocked activation of the unfolded protein response (UPR) and autophagy of the endoplasmic reticulum (ER-phagy). Overall, our results indicate that ESCRT-0 plays critical roles in regulating fungal development, virulence, autophagy and ER-phagy in M. oryzae.


Assuntos
Magnaporthe , Oryza , Ascomicetos , Autofagia/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Magnaporthe/metabolismo , Oryza/microbiologia , Doenças das Plantas/microbiologia , Esporos Fúngicos/metabolismo , Virulência
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