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1.
Nature ; 630(8016): 484-492, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38811729

RESUMEN

The CRISPR system is an adaptive immune system found in prokaryotes that defends host cells against the invasion of foreign DNA1. As part of the ongoing struggle between phages and the bacterial immune system, the CRISPR system has evolved into various types, each with distinct functionalities2. Type II Cas9 is the most extensively studied of these systems and has diverse subtypes. It remains uncertain whether members of this family can evolve additional mechanisms to counter viral invasions3,4. Here we identify 2,062 complete Cas9 loci, predict the structures of their associated proteins and reveal three structural growth trajectories for type II-C Cas9. We found that novel associated genes (NAGs) tended to be present within the loci of larger II-C Cas9s. Further investigation revealed that CbCas9 from Chryseobacterium species contains a novel ß-REC2 domain, and forms a heterotetrameric complex with an NAG-encoded CRISPR-Cas-system-promoting (pro-CRISPR) protein of II-C Cas9 (PcrIIC1). The CbCas9-PcrIIC1 complex exhibits enhanced DNA binding and cleavage activity, broader compatibility for protospacer adjacent motif sequences, increased tolerance for mismatches and improved anti-phage immunity, compared with stand-alone CbCas9. Overall, our work sheds light on the diversity and 'growth evolutionary' trajectories of II-C Cas9 proteins at the structural level, and identifies many NAGs-such as PcrIIC1, which serves as a pro-CRISPR factor to enhance CRISPR-mediated immunity.


Asunto(s)
Bacterias , Bacteriófagos , Proteína 9 Asociada a CRISPR , Sistemas CRISPR-Cas , Bacterias/virología , Bacterias/genética , Bacterias/inmunología , Bacteriófagos/genética , Bacteriófagos/inmunología , Chryseobacterium/genética , Chryseobacterium/inmunología , Chryseobacterium/virología , Proteína 9 Asociada a CRISPR/química , Proteína 9 Asociada a CRISPR/genética , Proteína 9 Asociada a CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Sistemas CRISPR-Cas/inmunología , División del ADN , Sitios Genéticos/genética , Modelos Moleculares , Dominios Proteicos
2.
Chromosoma ; 132(2): 89-103, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36939898

RESUMEN

Although parthenogenesis is widespread in nature and known to have close relationships with bisexuality, the transitional mechanism is poorly understood. Artemia is an ideal model to address this issue because bisexuality and "contagious" obligate parthenogenesis independently exist in its congeneric members. In the present study, we first performed chromosome spreading and immunofluorescence to compare meiotic processes of Artemia adopting two distinct reproductive ways. The results showed that, unlike conventional meiosis in bisexual Artemia, meiosis II in parthenogenic Artemia is entirely absent and anaphase I is followed by a single mitosis-like equational division. Interspecific comparative transcriptomics showed that two central molecules in homologous recombination (HR), Dmc1 and Rad51, exhibited significantly higher expression in bisexual versus parthenogenetic Artemia. qRT-PCR indicated that the expression of both genes peaked at the early oogenesis and gradually decreased afterward. Knocking-down by RNAi of Dmc1 in unfertilized females of bisexual Artemia resulted in a severe deficiency of homologous chromosome pairing and produced univalents at the middle oogenesis stage, which was similar to that of parthenogenic Artemia, while in contrast, silencing Rad51 led to no significant chromosome morphological change. Our results indicated that Dmc1 is vital for HR in bisexual Artemia, and the deficiency of Dmc1 may be correlated with or even possibly one of core factors in the transition from bisexuality to parthenogenesis.


Asunto(s)
Artemia , Recombinasas , Animales , Femenino , Recombinasas/genética , Artemia/genética , Artemia/metabolismo , Bisexualidad , Meiosis , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Partenogénesis/genética , Recombinasa Rad51/genética , Recombinasa Rad51/metabolismo
3.
Br J Anaesth ; 132(1): 45-52, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38007377

RESUMEN

BACKGROUND: Preliminary clinical trials of adamgammadex, a new cyclodextrin-based selective reversal agent, have demonstrated its efficacy in reversing neuromuscular block by rocuronium. METHODS: This multicentre, randomised, double-blind, positive-controlled, non-inferiority phase III clinical trial compared the efficacy and safety of adamgammadex and sugammadex. We randomised 310 subjects to receive adamgammadex (4 mg kg-1) or sugammadex (2 mg kg-1) at reappearance of the second twitch of the train-of-four (TOF), and standard safety data were collected. RESULTS: For the primary outcome, the proportion of patients with TOF ratio ≥0.9 within 5 min was 98.7% in the adamgammadex group vs 100% in the sugammadex group, with a point estimate and 95% confidence interval (CI) of 1.3% (-4.6%, +1.3%); the lower limit was greater than the non-inferiority margin of -10%. For the key secondary outcome, the median (inter quartile range) time from the start of administration of adamgammadex or sugammadex to recovery of TOF ratio to 0.9 was 2.25 (1.75, 2.75) min and 1.75 (1.50, 2.00) min, respectively. The difference was 0.50 (95% CI: 0.25, 0.50); the upper limit was lower than the non-inferiority margin of 5 min. In addition, there were no inferior results observed in secondary outcomes. Adamgammadex had a lower incidence of adverse drug reactions compared with sugammadex (anaphylactic reaction, recurarisation, decreased heart rate, and laryngospasm; P=0.047). CONCLUSIONS: Adamgammadex was non-inferior to sugammadex with a possible lower incidence of adverse drug reactions compared with sugammadex. Adamgammadex may have a potential advantage in terms of its overall risk-benefit profile. CLINICAL TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2000039525. Registered October 30, 2020. https://www.chictr.org.cn/showproj.html?proj=56825.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Bloqueo Neuromuscular , Fármacos Neuromusculares no Despolarizantes , gamma-Ciclodextrinas , Humanos , Sugammadex/efectos adversos , Rocuronio , Bloqueo Neuromuscular/métodos , gamma-Ciclodextrinas/efectos adversos , Fármacos Neuromusculares no Despolarizantes/efectos adversos , Androstanoles/efectos adversos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/etiología
4.
Biomed Eng Online ; 23(1): 56, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38890695

RESUMEN

OBJECTIVES: This study was designed to explore and validate the value of different machine learning models based on ultrasound image-omics features in the preoperative diagnosis of lymph node metastasis in pancreatic cancer (PC). METHODS: This research involved 189 individuals diagnosed with PC confirmed by surgical pathology (training cohort: n = 151; test cohort: n = 38), including 50 cases of lymph node metastasis. Image-omics features were extracted from ultrasound images. After dimensionality reduction and screening, eight machine learning algorithms, including logistic regression (LR), support vector machine (SVM), K-nearest neighbors (KNN), random forest (RF), extra trees (ET), extreme gradient boosting (XGBoost), light gradient boosting machine (LightGBM), and multilayer perceptron (MLP), were used to establish image-omics models to predict lymph node metastasis in PC. The best omics prediction model was selected through ROC curve analysis. Machine learning models were used to analyze clinical features and determine variables to establish a clinical model. A combined model was constructed by combining ultrasound image-omics and clinical features. Decision curve analysis (DCA) and a nomogram were used to evaluate the clinical application value of the model. RESULTS: A total of 1561 image-omics features were extracted from ultrasound images. 15 valuable image-omics features were determined by regularization, dimension reduction, and algorithm selection. In the image-omics model, the LR model showed higher prediction efficiency and robustness, with an area under the ROC curve (AUC) of 0.773 in the training set and an AUC of 0.850 in the test set. The clinical model constructed by the boundary of lesions in ultrasound images and the clinical feature CA199 (AUC = 0.875). The combined model had the best prediction performance, with an AUC of 0.872 in the training set and 0.918 in the test set. The combined model showed better clinical benefit according to DCA, and the nomogram score provided clinical prediction solutions. CONCLUSION: The combined model established with clinical features has good diagnostic ability and can be used to predict lymph node metastasis in patients with PC. It is expected to provide an effective noninvasive method for clinical decision-making, thereby improving the diagnosis and treatment of PC.


Asunto(s)
Metástasis Linfática , Aprendizaje Automático , Neoplasias Pancreáticas , Ultrasonografía , Humanos , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/patología , Metástasis Linfática/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Femenino , Anciano , Procesamiento de Imagen Asistido por Computador/métodos , Adulto
5.
Dig Dis Sci ; 69(7): 2462-2476, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38653944

RESUMEN

OBJECTIVE: To explore the expression of the ten eleven translocation (TET) 2 protein in early esophageal squamous cell carcinoma (EESCC), precancerous lesions, and cell lines and to evaluate the effect of TET2 on the functional behavior of EC109 esophageal cancer cells. METHODS: Thirty-one samples of EESCC and precancerous lesions collected via endoscopic submucosal dissection at Taihe Hospital, Shiyan, from February 1, 2017, to February 1, 2019, were analyzed. The study involved evaluating TET2 expression levels in lesion tissue and adjacent normal epithelium, correlating these with clinical pathological features. Techniques including 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide, cell scratch assays, flow cytometry for propidium iodide (PI) staining, Hoechst 333258/PI double staining, and nude mouse tumorigenesis experiments were employed to assess the effect of TET2 on the proliferation, migration, cell cycle, apoptosis, and tumorigenic ability of esophageal cancer cells. RESULTS: TET2 expression was notably reduced in early esophageal cancer tissue and correlated with tumor invasion depth (P < 0.05). Overexpression of TET2 enhanced the proliferation and migration of esophageal cancer cells, increased the cell population in the G0 phase, decreased it in the S phase, and intensified cell necrosis (P < 0.05). There was a partial increase in tumorigenic ability (P = 0.087). CONCLUSION: TET2 downregulation in ESCC potentially influences the necrosis, cell cycle, and tumorigenic ability of esophageal cancer cells, suggesting a role in the onset and progression of esophageal cancer.


Asunto(s)
Proteínas de Unión al ADN , Dioxigenasas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Proteínas Proto-Oncogénicas , Animales , Femenino , Humanos , Masculino , Ratones , Persona de Mediana Edad , Apoptosis , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Dioxigenasas/genética , Dioxigenasas/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Regulación hacia Abajo , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas de Esófago/metabolismo , Carcinoma de Células Escamosas de Esófago/patología , Carcinoma de Células Escamosas de Esófago/genética , Regulación Neoplásica de la Expresión Génica , Ratones Desnudos , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/genética
6.
Neurol Sci ; 45(5): 1897-1911, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38182844

RESUMEN

Delirium is a common complication in acute stroke patients. A 2011 meta-analysis showed an increased risk of in-hospital mortality and mortality within 12 months post-stroke, longer hospitalization durations, and increased likelihood of being discharged to a nursing home for patients experiencing post-stroke delirium. There is a need for an updated meta-analysis with several new studies having been since published. The PubMed and Scopus databases were screened for relevant studies. Inclusion criteria were as follows: retrospective or prospective studies reporting on the effects of delirium accompanying acute stroke on mortality, functional outcomes, length of hospital stay and need for re-admission. Strength of association was presented as pooled adjusted relative risk (RR) for categorical outcomes and weighted mean difference (WMD) for continuous outcomes. Statistical analysis was done using STATA version 16.0. The meta-analysis included 22 eligible articles. Eighteen of the 22 studies were prospective follow ups. Included studies were of good quality. Post-stroke delirium was associated with increased risk of in-hospital mortality, as well as mortality within 12 months post-stroke. Patients with delirium experienced increased hospital stay durations, were at greater risk for hospital readmission, and showed elevated risk for poor functional outcome. Compared to those who did not have delirium, stroke patients with delirium were 42% less likely to be discharged to home. Acute stroke patients with delirium are at an increased risk for poor short- and long-term outcomes. More research is needed to identify the best set of interventions to manage such patients and improve outcomes.


Asunto(s)
Delirio , Accidente Cerebrovascular , Humanos , Delirio/etiología , Delirio/epidemiología , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/mortalidad , Mortalidad Hospitalaria
7.
Biochem J ; 480(5): 385-401, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36852878

RESUMEN

Doublesex (DSX) proteins are members of the Doublesex/mab-3-related (DMRT) protein family and play crucial roles in sex determination and differentiation among the animal kingdom. In the present study, we identified two Doublesex (Dsx)-like mRNA isoforms in the brine shrimp Artemia franciscana (Kellogg 1906), which are generated by the combination of alternative promoters, alternative splicing and alternative polyadenylation. The two transcripts exhibited sex-biased enrichment, which we termed AfrDsxM and AfrDsxF. They share a common region which encodes an identical N-terminal DNA-binding (DM) domain. RT-qPCR analyses showed that AfrDsxM is dominantly expressed in male Artemia while AfrDsxF is specifically expressed in females. Expression levels of both isoforms increased along with the developmental stages of their respective sexes. RNA interference with dsRNA showed that the knockdown of AfrDsxM in male larvae led to the appearance of female traits including an ovary-like structure in the original male reproductive system and an elevated expression of vitellogenin. However, silencing of AfrDsxF induced no clear phenotypic change in female Artemia. These results indicated that the male AfrDSXM may act as inhibiting regulator upon the default female developmental mode in Artemia. Furthermore, electrophoretic mobility shift assay analyses revealed that the unique DM domain of AfrDSXs can specifically bind to promoter segments of potential downstream target genes like AfrVtg. These data show that AfrDSXs play crucial roles in regulating sexual development in Artemia, and further provide insight into the evolution of sex determination/differentiation in sexual organisms.


Asunto(s)
Artemia , Isoformas de ARN , Animales , Masculino , Femenino , Artemia/genética , Isoformas de ARN/metabolismo , Empalme Alternativo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Diferenciación Sexual/genética
8.
Artículo en Inglés | MEDLINE | ID: mdl-38639616

RESUMEN

Objective: Network pharmacology is an emerging discipline that applies computational methods to understand drug actions and interactions with multiple molecular targets. Xiao'ai Jiedu is a valued traditional Chinese medicine preparation for which the mechanism of action is not yet established. This study aims to explore the mechanism of Xiao'ai Jiedu in treating lung cancer through network pharmacology. Methods: First, the Traditional Chinese Medicine Systems Pharmacology (TCMSP) data platform was used to analyze the target treatment results of different medicinal materials in Mr. Zhou's cancer prescriptions. Then, functional enrichment analysis was performed to conduct a secondary analysis of the dissemination of cancer biological and pharmacological information in the human body. The Cancer Genome Atlas (TCGA) was used to obtain several cancer-aggressive target groups, and their transcription RNA was extracted for collection. The CIBERSORT evaluation method was used to conduct a Spearman correlation analysis on the data processing results. Then the matching degree between the experimental cells and the principle of drug treatment was analyzed to improve the statistical analysis. Results: Pharmacology research results showed that the network can accurately eliminate cancer detoxification targeted target correlation set, and through the data interpretation found that four different gene transcription have significant influence on lung cancer. The findings also confirmed that the degree of immune cell infiltration has a key role in lung cancer The study summarizes the active ingredients and their targets and mechanisms of action of the elimination of Xiao'ai Jiedu formula for the treatment of lung cancer. Conclusion: Network pharmacology can carry on the processing of the data, find the key to conform to the goal of research data, and the corresponding results are obtained, and the development of network pharmacology is not limited to, the study of lung cancer.

9.
J Med Virol ; 95(1): e27732, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35315116

RESUMEN

Hepatocellular carcinoma (HCC) often occurs following chronic hepatitis B virus (HBV) infection, leading to high recurrence and a low 5-year survival rate. We developed an overall survival (OS) prediction model based on protein expression profiles in HBV-infected nontumor liver tissues. We aimed to demonstrate the feasibility of using protein expression profiles in nontumor liver tissues for survival prediction. A univariate Cox and differential expression analysis were performed to identify candidate prognostic factors. A multivariate Cox analysis was performed to develop the liver gene prognostic index (LGPI). The survival differences between the different risk groups in the training and validation cohorts were also estimated. A total of 363 patients, 159 in the training cohort, and 204 in the validation cohort were included. Of the 6478 proteins extracted from nontumor liver tissues, we identified 1275 proteins altered between HCC and nontumor liver tissues. A total of 1090 out of 6478 proteins were significantly related to OS. The prognostic values of the proteins in nontumor tissues were mostly positively related to those in the tumor tissues. Protective proteins were mainly enriched in the metabolism-related pathways. From the differentially expressed proteins, the top 10 most significant prognosis-related proteins were submitted for LGPI construction. In the training and validation cohorts, this LGPI showed a great ability for distinguishing patients' OS risk stratifications. After adjusting for clinicopathological features, the LGPI was an independent prognostic factor in the training and validation cohorts. We demonstrated the prognostic value of protein expression profiling in nontumor liver tissues. The proposed LGPI was a promising predictive model for estimating OS in HBV-related HCC.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis B Crónica , Hepatitis B , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Pronóstico , Hepatitis B Crónica/complicaciones , Proteómica , Virus de la Hepatitis B/genética , Biomarcadores , Biomarcadores de Tumor/genética
10.
Allergy ; 78(3): 752-766, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36445014

RESUMEN

BACKGROUND: Atopic diseases are characterized by IgE antibody responses that are dependent on cognate CD4 T cell help and T cell-produced IL-4 and IL-13. Current models of IgE cell differentiation point to the role of IgG memory B cells as precursors of pathogenic IgE plasma cells. The goal of this work was to identify intrinsic features of memory B cells that are associated with IgE production in atopic diseases. METHODS: Peripheral blood B lymphocytes were collected from individuals with physician diagnosed asthma or atopic dermatitis (AD) and from non-atopic individuals. These samples were analyzed by spectral flow cytometry, single cell RNA sequencing (scRNAseq), and in vitro activation assays. RESULTS: We identified a novel population of IgG memory B cells characterized by the expression of IL-4/IL-13 regulated genes FCER2/CD23, IL4R, IL13RA1, and IGHE, denoting a history of differentiation during type 2 immune responses. CD23+ IL4R+ IgG+ memory B cells had increased occurrence in individuals with atopic disease. Importantly, the frequency of CD23+ IL4R+ IgG+ memory B cells correlated with levels of circulating IgE. Consistently, in vitro stimulated B cells from atopic individuals generated more IgE+ cells than B cells from non-atopic subjects. CONCLUSIONS: These findings suggest that CD23+ IL4R+ IgG+ memory B cells transcribing IGHE are potential precursors of IgE plasma cells and are linked to pathogenic IgE production.


Asunto(s)
Células B de Memoria , Receptores de IgE , Humanos , Receptores de IgE/metabolismo , Interleucina-13 , Interleucina-4 , Inmunoglobulina E , Inmunoglobulina G , Subunidad alfa del Receptor de Interleucina-4 , Lectinas Tipo C
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