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1.
Artigo em Inglês | MEDLINE | ID: mdl-38758667

RESUMO

OBJECTIVE: Synthesizing and evaluating inconsistent medical evidence is essential in evidence-based medicine. This study aimed to employ ChatGPT as a sophisticated scientific reasoning engine to identify conflicting clinical evidence and summarize unresolved questions to inform further research. MATERIALS AND METHODS: We evaluated ChatGPT's effectiveness in identifying conflicting evidence and investigated its principles of logical reasoning. An automated framework was developed to generate a PubMed dataset focused on controversial clinical topics. ChatGPT analyzed this dataset to identify consensus and controversy, and to formulate unsolved research questions. Expert evaluations were conducted 1) on the consensus and controversy for factual consistency, comprehensiveness, and potential harm and, 2) on the research questions for relevance, innovation, clarity, and specificity. RESULTS: The gpt-4-1106-preview model achieved a 90% recall rate in detecting inconsistent claim pairs within a ternary assertions setup. Notably, without explicit reasoning prompts, ChatGPT provided sound reasoning for the assertions between claims and hypotheses, based on an analysis grounded in relevance, specificity, and certainty. ChatGPT's conclusions of consensus and controversies in clinical literature were comprehensive and factually consistent. The research questions proposed by ChatGPT received high expert ratings. DISCUSSION: Our experiment implies that, in evaluating the relationship between evidence and claims, ChatGPT considered more detailed information beyond a straightforward assessment of sentimental orientation. This ability to process intricate information and conduct scientific reasoning regarding sentiment is noteworthy, particularly as this pattern emerged without explicit guidance or directives in prompts, highlighting ChatGPT's inherent logical reasoning capabilities. CONCLUSION: This study demonstrated ChatGPT's capacity to evaluate and interpret scientific claims. Such proficiency can be generalized to broader clinical research literature. ChatGPT effectively aids in facilitating clinical studies by proposing unresolved challenges based on analysis of existing studies. However, caution is advised as ChatGPT's outputs are inferences drawn from the input literature and could be harmful to clinical practice.

2.
Plant Cell Rep ; 43(6): 154, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809335

RESUMO

KEY MESSAGE: Integrated omics analyses outline the cellular and metabolic events of hemp plants in response to salt stress and highlight several photosynthesis and energy metabolism related pathways as key regulatory points. Soil salinity affects many physiological processes of plants and leads to crop yield losses worldwide. For hemp, a crop that is valued for multiple aspects, such as its medical compounds, fibre, and seed, a comprehensive understanding of its salt stress responses is a prerequisite for resistance breeding and tailoring its agronomic performance to suit certain industrial applications. Here, we first observed the phenotype of salt-stressed hemp plants and found that under NaCl treatment, hemp plants displayed pronounced growth defects, as indicated by the significantly reduced average height, number of leaves, and chlorophyll content. Next, we conducted comparative proteomics and metabolomics to dissect the complex salt-stress response mechanisms. A total of 314 proteins and 649 metabolites were identified to be differentially behaving upon NaCl treatment. Functional classification and enrichment analysis unravelled that many differential proteins were proteases associated with photosynthesis. Through metabolic pathway enrichment, several energy-related pathways were found to be altered, such as the biosynthesis and degradation of branched-chain amino acids, and our network analysis showed that many ribosomal proteins were involved in these metabolic adaptations. Taken together, for hemp plants, influences on chloroplast function probably represent a major toxic effect of salinity, and modulating several energy-producing pathways possibly through translational regulation is presumably a key protective mechanism against the negative impacts. Our data and analyses provide insights into our understanding of hemp's stress biology and may lay a foundation for future functional genomics studies.


Assuntos
Cannabis , Metabolômica , Proteínas de Plantas , Proteômica , Salinidade , Cannabis/metabolismo , Cannabis/genética , Cannabis/fisiologia , Cannabis/efeitos dos fármacos , Proteômica/métodos , Metabolômica/métodos , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Estresse Salino , Fotossíntese/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Estresse Fisiológico , Folhas de Planta/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Cloreto de Sódio/farmacologia , Clorofila/metabolismo , Metaboloma/efeitos dos fármacos , Fenótipo
3.
BMC Plant Biol ; 24(1): 244, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38575936

RESUMO

BACKGROUND: This study aims to decipher the genetic basis governing yield components and quality attributes of peanuts, a critical aspect for advancing molecular breeding techniques. Integrating genotype re-sequencing and phenotypic evaluations of seven yield components and two grain quality traits across four distinct environments allowed for the execution of a genome-wide association study (GWAS). RESULTS: The nine phenotypic traits were all continuous and followed a normal distribution. The broad heritability ranged from 88.09 to 98.08%, and the genotype-environment interaction effects were all significant. There was a highly significant negative correlation between protein content (PC) and oil content (OC). The 10× genome re-sequencing of 199 peanut accessions yielded a total of 631,988 high-quality single nucleotide polymorphisms (SNPs), with 374 significant SNP loci identified in association with the nine traits of interest. Notably, 66 of these pertinent SNPs were detected in multiple environments, and 48 of them were linked to multiple traits of interest. Five loci situated on chromosome 16 (Chr16) exhibited pleiotropic effects on yield traits, accounting for 17.64-32.61% of the observed phenotypic variation. Two loci on Chr08 were found to be strongly associated with protein and oil contents, accounting for 12.86% and 14.06% of their respective phenotypic variations, respectively. Linkage disequilibrium (LD) block analysis of these seven loci unraveled five nonsynonymous variants, leading to the identification of one yield-related candidate gene and two quality-related candidate genes. The correlation between phenotypic variation and SNP loci in these candidate genes was validated by Kompetitive allele-specific PCR (KASP) marker analysis. CONCLUSIONS: Overall, molecular markers were developed for genetic loci associated with yield and quality traits through a GWAS investigation of 199 peanut accessions across four distinct environments. These molecular tools can aid in the development of desirable peanut germplasm with an equilibrium of yield and quality through marker-assisted breeding.


Assuntos
Arachis , Estudo de Associação Genômica Ampla , Arachis/genética , Locos de Características Quantitativas/genética , Melhoramento Vegetal , Mapeamento Cromossômico/métodos , Fenótipo , Polimorfismo de Nucleotídeo Único/genética
4.
Infect Med (Beijing) ; 3(1): 100094, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38444746

RESUMO

Background: In this study, we present a case of Japanese spotted fever (JSF) caused by Rickettsia japonica and use this case to investigate the process of diagnosing and reintegrating traceability of infectious diseases via metagenomic next-generation sequencing (mNGS). Methods: From data relating to epidemiological history, clinical and laboratory examinations, and mNGS sequencing, a diagnosis of severe JSF was concluded. Results: A detailed field epidemiological investigation discovered parasitic Haemaphysalis longicornis from a host animal (dog) in the domicile of the patient, within which R. japonica was detected, along with a diverse array of other potentially pathogenic microorganisms that could cause other infectious diseases. Conclusion: The mNGS provided an efficient method to diagnose JSF infection. This methodology could also be applied to field epidemiological investigations to establish the traceability of infectious diseases.

6.
Mar Pollut Bull ; 197: 115729, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37913562

RESUMO

Photodegradation significantly influences marine oil spill behavior, yet its role remains underrepresented in current models, impairing predictive accuracy. Addressing this, our study rigorously examined oil properties and environmental determinants affecting marine oil spill photodegradation through laboratory simulations. We identified and quantified key factors and their interactions, noting particularly the positive influence of asphaltene and negative implications of oil density. We also discerned a negative correlation between n-alkane degradation and carbon numbers. Our findings underscored the pivotal roles of temperature and irradiance in photodegradation. All tested oils adhered to first-order kinetics, with rate constants ranging from 0.0348 to 0.0645 day-1. Finally, we introduced a novel model incorporating temperature, irradiance and their interactions, ensuring reasonable simulations for marine oil spill photodegradation, fortifying marine oil spill management strategies.


Assuntos
Poluição por Petróleo , Poluentes Químicos da Água , Poluição por Petróleo/análise , Fotólise , Óleos
7.
Front Microbiol ; 14: 1265139, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37849919

RESUMO

Polyethylene terephthalate (PET) is a synthetic polymer in the polyester family. It is widely found in objects used daily, including packaging materials (such as bottles and containers), textiles (such as fibers), and even in the automotive and electronics industries. PET is known for its excellent mechanical properties, chemical resistance, and transparency. However, these features (e.g., high hydrophobicity and high molecular weight) also make PET highly resistant to degradation by wild-type microorganisms or physicochemical methods in nature, contributing to the accumulation of plastic waste in the environment. Therefore, accelerated PET recycling is becoming increasingly urgent to address the global environmental problem caused by plastic wastes and prevent plastic pollution. In addition to traditional physical cycling (e.g., pyrolysis, gasification) and chemical cycling (e.g., chemical depolymerization), biodegradation can be used, which involves breaking down organic materials into simpler compounds by microorganisms or PET-degrading enzymes. Lipases and cutinases are the two classes of enzymes that have been studied extensively for this purpose. Biodegradation of PET is an attractive approach for managing PET waste, as it can help reduce environmental pollution and promote a circular economy. During the past few years, great advances have been accomplished in PET biodegradation. In this review, current knowledge on cutinase-like PET hydrolases (such as TfCut2, Cut190, HiC, and LCC) was described in detail, including the structures, ligand-protein interactions, and rational protein engineering for improved PET-degrading performance. In particular, applications of the engineered catalysts were highlighted, such as improving the PET hydrolytic activity by constructing fusion proteins. The review is expected to provide novel insights for the biodegradation of complex polymers.

8.
Front Bioeng Biotechnol ; 11: 1263996, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37795175

RESUMO

Poly(ethylene terephthalate) (PET) is a highly useful synthetic polyester plastic that is widely used in daily life. However, the increase in postconsumer PET as plastic waste that is recalcitrant to biodegradation in landfills and the natural environment has raised worldwide concern. Currently, traditional PET recycling processes with thermomechanical or chemical methods also result in the deterioration of the mechanical properties of PET. Therefore, it is urgent to develop more efficient and green strategies to address this problem. Recently, a novel mesophilic PET-degrading enzyme (IsPETase) from Ideonella sakaiensis was found to streamline PET biodegradation at 30°C, albeit with a lower PET-degrading activity than chitinase or chitinase-like PET-degrading enzymes. Consequently, the molecular engineering of more efficient PETases is still required for further industrial applications. This review details current knowledge on IsPETase, MHETase, and IsPETase-like hydrolases, including the structures, ligand‒protein interactions, and rational protein engineering for improved PET-degrading performance. In particular, applications of the engineered catalysts are highlighted, including metabolic engineering of the cell factories, enzyme immobilization or cell surface display. The information is expected to provide novel insights for the biodegradation of complex polymers.

9.
Curr Top Med Chem ; 23(20): 1973-1984, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37264622

RESUMO

Nonribosomal peptide synthetases, consisted of multiple catalytic domains, are involved in the biosynthesis of an important family of bioactive natural products in a coordinated manner. Among the functional domains, adenylation domains are specifically responsible for recognizing carboxylic acid building blocks and synthesizing aminoacyl adenylates. Given their critical roles in the biosynthesis of the growing peptide, A-domains are also referred to as the "gatekeeper". In this review, very recent developments on the A-domains from NRPSs are reviewed to expand the fundamental knowledge of the A domain, including knowledge on the structures, functions, and molecular interactions. Several recent examples were also discussed to highlight the great potential of A-domain engineering. This study should provide a framework for the combinatorial biosynthesis or synthetic biology-driven microbial production of novel nonribosomal peptides.


Assuntos
Peptídeo Sintases , Peptídeos , Domínio Catalítico , Peptídeo Sintases/genética , Peptídeo Sintases/química , Peptídeo Sintases/metabolismo , Peptídeos/química , Monofosfato de Adenosina
10.
Front Oncol ; 13: 1136049, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37114132

RESUMO

Introduction: Early-stage accurate diagnosis of malignant pleural mesothelioma (MPM) has always been a formidable challenge. DNA and protein as biomarkers for the diagnosis of MPM have received considerable attention, and yet the outcomes are inconsistent. Methods: In this study, a systematic search employing PubMed, EMBASE, and Cochrane Library to identify relevant studies from the first day of databases to October 2021. Moreover, we adopt the QUADAS-2 to evaluate the quality of eligible studies and Stata 15.0 and Review Manager 5.4 software programs to perform the meta-analysis. Additionally, bioinformatics analysis was performed at GEPIA for the purpose of exploring relationship between related genes and the survival time of MPM patients. Results: We included 15 studies at the DNA level and 31studies at the protein level in this meta-analysis. All results demonstrated that the diagnostic accuracy of the combination of MTAP + Fibulin-3 was the highest with the SEN 0.81 (95% CI: 0.67, 0.89) and the SPE 0.95 (95% CI: 0.90, 0.97). And the bioinformatics analysis indicated that the higher MTAP gene expression level was beneficial to enhance the survival time of MPM patients. Discussion: Nonetheless, as a result of the limitations of the included samples, it may be necessary to conduct additional research before drawing conclusions. Systematic review registration: https://inplasy.com/inplasy-2022-10-0043/, identifier INPLASY2022100043.

11.
Sheng Wu Gong Cheng Xue Bao ; 39(3): 1131-1141, 2023 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-36994577

RESUMO

The α-amino acid ester acyltransferase (SAET) from Sphingobacterium siyangensis is one of the enzymes with the highest catalytic ability for the biosynthesis of l-alanyl-l-glutamine (Ala-Gln) with unprotected l-alanine methylester and l-glutamine. To improve the catalytic performance of SAET, a one-step method was used to rapidly prepare the immobilized cells (SAET@ZIF-8) in the aqueous system. The engineered Escherichia coli (E. coli) expressing SAET was encapsulated into the imidazole framework structure of metal organic zeolite (ZIF-8). Subsequently, the obtained SAET@ZIF-8 was characterized, and the catalytic activity, reusability and storage stability were also investigated. Results showed that the morphology of the prepared SAET@ZIF-8 nanoparticles was basically the same as that of the standard ZIF-8 materials reported in literature, and the introduction of cells did not significantly change the morphology of ZIF-8. After repeated use for 7 times, SAET@ZIF-8 could still retain 67% of the initial catalytic activity. Maintained at room temperature for 4 days, 50% of the original catalytic activity of SAET@ZIF-8 could be retained, indicating that SAET@ZIF-8 has good stability for reuse and storage. When used in the biosynthesis of Ala-Gln, the final concentration of Ala-Gln reached 62.83 mmol/L (13.65 g/L) after 30 min, the yield reached 0.455 g/(L·min), and the conversion rate relative to glutamine was 62.83%. All these results suggested that the preparation of SAET@ZIF-8 is an efficient strategy for the biosynthesis of Ala-Gln.


Assuntos
Escherichia coli , Zeolitas , Escherichia coli/genética , Glutamina , Zeolitas/química , Aminoácidos
13.
Mol Biol Rep ; 50(1): 361-376, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36334232

RESUMO

BACKGROUND: Peach (Prunus persica L.) is prone to chilling injury as exhibited by inhibition of the ethylene production, failure in softening, and the manifestation of internal browning. The basic leucine zipper (bZIP) transcription factors play an essential role in regulatory networks that control many processes associated with physiological, abiotic and biotic stress responses in fruits. Formerly, the underlying molecular and regulatory mechanism of (bZIP) transcription factors responsive to chilling injury in peach fruit is still elusive. METHODS AND RESULTS: In the current experiment, the solute peach 'Zhongyou Peach No. 13' was used as the test material and cold storage at low temperature (4 °C). It was found that long-term low-temperature storage induced the production of ethylene, the hardness of the pulp decreased, and the low temperature also induced ABA accumulation. The changes of ABA and ethylene in peach fruits during low-temperature storage were clarified. Since the bZIP transcription factor is involved in the regulation of downstream pathways of ABA signals, 47 peach bZIP transcription factor family genes were identified through bioinformatics analysis. Further based on RT-qPCR analysis, 18 PpbZIP genes were discovered to be expressed in refrigerated peach fruits. Among them, the expression of PpbZIP23 and PpbZIP25 was significantly reduced during the refrigeration process, the promoter analysis of these genes found that this region contains the MYC/MYB/ABRES binding element, but not the DRES/CBFS element, indicating that the expression may be regulated by the ABA-dependent cold induction pathway, thereby responding to chilling injury in peach fruit. CONCLUSIONS: Over investigation will provide new insights for further postharvest protocols related to molecular changes during cold storage and will prove a better cope for chilling injury.


Assuntos
Prunus persica , Prunus persica/genética , Prunus persica/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Frutas/metabolismo , Zíper de Leucina , Etilenos/metabolismo , Temperatura Baixa , Regulação da Expressão Gênica de Plantas/genética
14.
Front Microbiol ; 14: 1264939, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38192286

RESUMO

Introduction: As tick-borne diseases rise to become the second most prevalent arthropod-transmitted disease globally, the increasing investigations focus on ticks correspondingly. Factors contributed to this increase include anthropogenic influences, changes in vertebrate faunal composition, social-recreational shifts, and climatic variation. Employing the 16S gene sequence method in next-generation sequencing (NGS) allows comprehensive pathogen identification in samples, facilitating the development of refined approaches to tick research omnidirectionally. Methods: In our survey, we compared the microbial richness and biological diversity of ticks in Wuwei City, Gansu province, differentiating between questing ticks found in grass and parasitic ticks collected from sheep based on 16S NGS method. Results: The results show Rickettsia, Coxiella, and Francisella were detected in all 50 Dermacentor nuttalli samples, suggesting that the co-infection may be linked to specific symbiotic bacteria in ticks. Our findings reveal significant differences in the composition and diversity of microorganisms, with the Friedmanniella and Bordetella genera existing more prevalent in parasitic ticks than in questing ticks (p < 0.05). Additionally, the network analysis demonstrates that the interactions among bacterial genera can be either promotive or inhibitive in ticks exhibiting different lifestyles with the correlation index |r| > 0.6. For instance, Francisella restrains the development of 10 other bacteria in parasitic ticks, whereas Phyllobacterium and Arthrobacter enhance colonization across all tick species. Discussion: By leveraging NGS techniques, our study reveals a high degree of species and phylogenetic diversity within the tick microbiome. It further highlights the potential to investigate the interplay between bacterial genera in both parasitic and questing ticks residing in identical habitat environments.

15.
PLoS Genet ; 18(12): e1010513, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36477175

RESUMO

Walnut (Juglans) species are economically important hardwood trees cultivated worldwide for both edible nuts and high-quality wood. Broad-scale assessments of species diversity, evolutionary history, and domestication are needed to improve walnut breeding. In this study, we sequenced 309 walnut accessions from around the world, including 55 Juglans relatives, 98 wild Persian walnuts (J. regia), 70 J. regia landraces, and 86 J. regia cultivars. The phylogenetic tree indicated that J. regia samples (section Dioscaryon) were monophyletic within Juglans. The core areas of genetic diversity of J. regia germplasm were southwestern China and southern Asia near the Qinghai-Tibet Plateau and the Himalayas, and the uplift of the Himalayas was speculated to be the main factor leading to the current population dynamics of Persian walnut. The pattern of genomic variation in terms of nucleotide diversity, linkage disequilibrium, single nucleotide polymorphisms, and insertions/deletions revealed the domestication and selection footprints in Persian walnut. Selective sweep analysis, GWAS, and expression analysis further identified two transcription factors, JrbHLH and JrMYB6, that influence the thickness of the nut diaphragm as loci under selection during domestication. Our results elucidate the domestication and selection footprints in Persian walnuts and provide a valuable resource for the genomics-assisted breeding of this important crop.


Assuntos
Juglans , Juglans/genética , Filogenia , Ásia Meridional , China , Genômica
16.
Diagnostics (Basel) ; 12(9)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36140611

RESUMO

In previous studies, non-invasive diagnostic biomarkers showed great benefit in the early-stage diagnosis of malignant pleural mesothelioma (MPM). However, the accuracy of different biomarkers was controversial. In this study, meta-analysis and bioinformatics analysis were conducted to compare the accuracy of the following three biomarkers and explore the relationship between the gene expression levels and MPM. A systematic search of meta-analysis was conducted using PubMed, EMBASE and Cochrane Library to identify relevant studies from the inception to March 2021. QUADAS-2 for Quality Assessment of Diagnostic Accuracy Studies was used to evaluate the quality of eligible studies. The meta-analysis was performed utilizing Stata 15.0 and Review Manager 5.4 software. The meta-analysis results showed that 31 studies that involved 8750 participants were included. The pooled sensitivity and specificity (SPE) were 0.90 (95% CI: 0.74, 0.97) and 0.91 (95% CI: 0.84, 0.95) for Fibulin-3, 0.66 (95% CI, 0.51-0.78) and 0.91 (95% CI, 0.82-0.96) for mesothelin (MSLN), 0.68 (95% CI: 0.63,0.73) and 0.86 (95% CI: 0.82,0.90) for soluble mesothelin-related peptides (SMRP), and 0.74 (95% CI, 0.66-0.80) and 0.89 (95% CI, 0.85-0.91) for MSLN + SMRP + Fibulin-3. Compared with the other two biomarkers, Fibulin-3 may be more appropriate to be one of the indicators for combined diagnosis. Bioinformatics analysis showed that the low expression level of the MSLN gene was significantly related to longer survival time and better prognosis of MPM patients. However, considering the limitation in the quality and sample size of the included research, further studies are required.

17.
BMC Plant Biol ; 22(1): 459, 2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36153492

RESUMO

BACKGROUND: Fruit tree yield and fruit quality are affected by the tree's growth type, and branching angle is an important agronomic trait of fruit trees, which largely determines the crown structure. The weeping type of peach tree shows good ventilation and light transmission; therefore, it is commonly cultivated. However, there is no molecular marker closely linked with peach weeping traits for target gene screening and assisted breeding. RESULTS: First, we confirmed that the peach weeping trait is a recessive trait controlled by a single gene by constructing segregating populations. Based on BSA-seq, we mapped the gene controlling this trait within 159 kb of physical distance on chromosome 3. We found a 35 bp deletion in the candidate area in standard type, which was not lacking in weeping type. For histological assessments, different types of branches were sliced and examined, showing fiber bundles in the secondary xylem of ordinary branches but not in weeping branches. CONCLUSIONS: This study established a molecular marker that is firmly linked to weeping trait. This marker can be used for the selection of parents in the breeding process and the early screening of hybrid offspring to shorten the breeding cycle. Moreover, we preliminary explored histological differences between growth types. These results lay the groundwork for a better understanding of the weeping growth habit of peach trees.


Assuntos
Prunus persica , Frutas/genética , Fenótipo , Melhoramento Vegetal , Prunus persica/genética
18.
Front Oncol ; 12: 975846, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36119520

RESUMO

Background: The prognostic performance of four lymph node classifications, the 8th American Joint Committee on Cancer (AJCC) Tumor Node Metastasis (TNM) N stage, lymph node ratio (LNR), log odds of positive lymph nodes (LODDS), and examined lymph nodes (ELN) in early-onset pancreatic cancer (EOPC) remains unclear. Methods: The Surveillance, Epidemiology, and End Results (SEER) database was searched for patients with EOPC from 2004 to 2016. 1048 patients were randomly divided into training (n = 733) and validation sets (n = 315). The predictive abilities of the four lymph node staging systems were compared using the Akaike information criteria (AIC), receiver operating characteristic area under the curve (AUC), and C-index. Multivariate Cox analysis was performed to identify independent risk factors. A nomogram based on lymph node classification with the strongest predictive ability was established. The nomogram's precision was verified by the C-index, calibration curves, and AUC. Kaplan-Meier analysis and log-rank tests were used to compare differences in survival at each stage of the nomogram. Results: Compared with the 8th N stage, LODDS, and ELN, LNR had the highest C-index and AUC and the lowest AIC. Multivariate analysis showed that N stage, LODDS, LNR were independent risk factors associated with cancer specific survival (CSS), but not ELN. In the training set, the AUC values for the 1-, 3-, and 5-year CSS of the nomogram were 0.663, 0.728, and 0.760, respectively and similar results were observed in the validation set. In addition, Kaplan-Meier survival analysis showed that the nomogram was also an important factor in the risk stratification of EOPC. Conclusion: We analyzed the predictive power of the four lymph node staging systems and found that LNR had the strongest predictive ability. Furthermore, the novel nomogram prognostic staging mode based on LNR was also an important factor in the risk stratification of EOPC.

19.
Vaccines (Basel) ; 10(4)2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35455313

RESUMO

MHC-I antigen processes and presentation trigger host-specific anti-viral cellular responses during infection, in which epitope-recognizing cytotoxic T lymphocytes eliminate infected cells and contribute to viral clearance through a cytolytic killing effect. In this study, Hantaan virus (HTNV) GP-derived 9-mer dominant epitopes were obtained with high affinity to major HLA-I and H-2 superfamilies. Further immunogenicity and conservation analyses selected 11 promising candidates, and molecule docking (MD) was then simulated with the corresponding MHC-I alleles. Two-way hierarchical clustering revealed the interactions between GP peptides and MHC-I haplotypes. Briefly, epitope hotspots sharing good affinity to a wide spectrum of MHC-I molecules highlighted the biomedical practice for vaccination, and haplotype clusters represented the similarities among individuals during T-cell response establishment. Cross-validation proved the patterns observed through both MD simulation and public data integration. Lastly, 148 HTNV variants yielded six types of major amino acid residue replacements involving four in nine hotspots, which minimally influenced the general potential of MHC-I superfamily presentation. Altogether, our work comprehensively evaluates the pan-MHC-I immunoreactivity of HTNV GP through a state-of-the-art workflow in light of comparative immunology, acknowledges present discoveries, and offers guidance for ongoing HTNV vaccine pursuit.

20.
Int Immunol ; 34(6): 313-325, 2022 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-35192720

RESUMO

Ebolavirus (EBOV) causes an extremely high mortality and prevalence disease called Ebola virus disease (EVD). There is only one glycoprotein (GP) on the virus particle surface, which mediates entry into the host cell. Major histocompatibility complex (MHC) class-I restricted cluster of differentiation 8 (CD8+) T cell responses are important antiviral immune responses. Therefore, it is of great importance to understand EBOV GP-specific MHC class-I restricted epitopes within immunogenicity. In this study, computational approaches were employed to predict the dominant MHC class-I molecule epitopes of EBOV GP for mouse H2 and major alleles of human leukocyte antigen (HLA) class-I supertypes. Our results yielded 42 dominant epitopes in H2 haplotypes and 301 dominant epitopes in HLA class-I haplotypes. After validation by enzyme-linked immunospot (ELISpot) assay, in-depth analyses to ascertain their nature of conservation, immunogenicity, and docking with the corresponding MHC class-I molecules were undertaken. Our study predicted MHC class-I restricted epitopes that may aid the advancement of anti-EBOV immune responses. An integrated strategy of epitope prediction, validation and comparative analyses was postulated, which is promising for epitope-based immunotherapy development and application to viral epidemics.


Assuntos
Ebolavirus , Animais , Epitopos de Linfócito T , Glicoproteínas , Antígenos HLA , Antígenos de Histocompatibilidade Classe I , Camundongos
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