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1.
Proc Natl Acad Sci U S A ; 121(35): e2320804121, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39172790

RESUMEN

Breast Cancer Type 1 Susceptibility Protein (BRCA1) is a tumor-suppressor protein that regulates various cellular pathways, including those that are essential for preserving genome stability. One essential mechanism involves a BRCA1-A complex that is recruited to double-strand breaks (DSBs) by RAP80 before initiating DNA damage repair (DDR). How RAP80 itself is recruited to DNA damage sites, however, is unclear. Here, we demonstrate an intrinsic correlation between a methyltransferase DOT1L-mediated RAP80 methylation and BRCA1-A complex chromatin recruitment that occurs during cancer cell radiotherapy resistance. Mechanistically, DOT1L is quickly recruited onto chromatin and methylates RAP80 at multiple lysines in response to DNA damage. Methylated RAP80 is then indispensable for binding to ubiquitinated H2A and subsequently triggering BRCA1-A complex recruitment onto DSBs. Importantly, DOT1L-catalyzed RAP80 methylation and recruitment of BRCA1 have clinical relevance, as inhibition of DOT1L or RAP80 methylation seems to enhance the radiosensitivity of cancer cells both in vivo and in vitro. These data reveal a crucial role for DOT1L in DDR through initiating recruitment of RAP80 and BRCA1 onto chromatin and underscore a therapeutic strategy based on targeting DOT1L to overcome tumor radiotherapy resistance.


Asunto(s)
Proteína BRCA1 , Reparación del ADN , Chaperonas de Histonas , N-Metiltransferasa de Histona-Lisina , Humanos , Proteína BRCA1/metabolismo , Proteína BRCA1/genética , Chaperonas de Histonas/metabolismo , Chaperonas de Histonas/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , N-Metiltransferasa de Histona-Lisina/genética , Metilación , Línea Celular Tumoral , Roturas del ADN de Doble Cadena , Cromatina/metabolismo , Metiltransferasas/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Animales , Femenino , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Ratones , Tolerancia a Radiación/genética , Metilación de ADN
2.
Biophys J ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39173628
3.
Sci Total Environ ; 951: 175563, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39153620

RESUMEN

Institutional controls, as an important measure for risk management of contaminated sites, is widely used in site management by the United States, Canada and European countries. At present, some regions in China have also begun to explore the implementation of institutional controls, but its path, safeguard mechanism, and tracking evaluation are still unclear. Based on China's unique contaminated site remediation control system and land management system, this paper proposes a framework for the whole life cycle institutional controls of China's contaminated sites: (1) evaluate the need for institutional controls; (2) establish the objectives of institutional controls; (3) identify the restrictive requirements of institutional controls; (4) establish the implementation form of institutional controls; and (5) regularly review the effectiveness of institutional controls. To demonstrate the applicability of the institutional control framework, a case demonstration study was conducted at a petrochemical contaminated site in China. By analyzing the information on residual pollutants after the implementation of risk management measures at the site, the exposure pathways and hazards in case of re-release, and the engineering facilities, we proposed eight restrictive requirements, including the prohibition of disturbing and damaging the clean and planted soil layers of the site and the protection of long-term monitoring wells. At the same time, we constructed a multi-departmental pathway to implement institutional controls in conjunction with ecological environment, natural resources and housing departments to ensure effective implementation of institutional controls. Eventually, we summarized a set of replicable and generalizable institutional controls application models, which provide valuable theoretical and practical support for China and other local governments in the implementation of institutional controls at contaminated sites.

4.
J Hazard Mater ; 477: 135376, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39111175

RESUMEN

Avermectin is a highly effective insecticide that has been widely used in agriculture since the 1990s. In recent years, the safety of avermectin for non-target organisms has received much attention. The vasculature is important organs in the body and participate in the composition of other organs. However, studies on the vascular safety of avermectin are lacking. The vasculature of zebrafish larvae is characterized by ease of observation and it is a commonly used model for vascular studies. Therefore, zebrafish larvae were used to explore the potential risk of avermectin on the vasculature. The results showed that avermectin induced vascular damage throughout the body of zebrafish larvae, including the head, eyes, intestine, somite, tail and other vasculature. The main forms of damage are reduction in vascular diameter, vascular area and vascular abundance. Meanwhile, avermectin induced a decrease in the number of endothelial cells and apoptosis within the vasculature. In addition, vascular damage may be related to impairment of mitochondrial function and mitochondria-mediated apoptosis. Finally, exploration of the molecular mechanisms revealed abnormal alterations in the expression of genes related to the VEGF/Notch signaling pathway. Therefore, the VEGF/Notch signaling pathway may be an important mechanism for avermectin-induced vascular damage in zebrafish larvae. This study demonstrates the vascular toxicity of avermectin in zebrafish larvae and reveals the possible molecular mechanism, which would hopefully draw more attention to the safety of avermectin in non-target organisms.


Asunto(s)
Apoptosis , Ivermectina , Larva , Mitocondrias , Receptores Notch , Transducción de Señal , Factor A de Crecimiento Endotelial Vascular , Pez Cebra , Animales , Ivermectina/análogos & derivados , Ivermectina/toxicidad , Apoptosis/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Larva/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Receptores Notch/metabolismo , Insecticidas/toxicidad , Vasos Sanguíneos/efectos de los fármacos
5.
Cancer Lett ; 599: 217152, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39094825

RESUMEN

Monoclonal antibodies targeting immune checkpoints have been widely applied in gastrointestinal cancer immunotherapy. However, systemic administration of various monoclonal antibodies does not often result in sustained effects in reversing the immunosuppressive tumor microenvironment (TME), which may be due to the spatiotemporal dynamic changes of immune checkpoints. Herein, we reported a novel immune checkpoint reprogramming strategy for gastrointestinal cancer immunotherapy. It was achieved by the sequential delivery of siPD-L1 (siRNA for programmed cell death ligand 1) and pOX40L (plasmid for OX40 ligand), which were complexed with two cationic polymer brush-grafted carbon nanotubes (dense short (DS) and dense long (DL)) designed based on the structural characteristics of nucleic acids and brush architectures. Upon administrating DL/pOX40L for the first three dosages, then followed by DS/siPD-L1 for the next three dosages to the TME, it upregulated the stimulatory checkpoint OX40L on dendritic cells (DCs) and downregulated inhibitory checkpoint PD-L1 on tumor cells and DCs in a sequential reprogramming manner. Compared with other combination treatments, this sequential strategy drastically boosted the DCs maturation, and CD8+ cytotoxic T lymphocytes infiltration in tumor site. Furthermore, it could augment the local antitumor response and improve the T cell infiltration in tumor-draining lymph nodes to reverse the peripheral immunosuppression. Our study demonstrated that sequential nucleic acid delivery strategy via personalized nanoplatforms effectively reversed the immunosuppression status in both tumor microenvironment and peripheral immune landscape, which significantly enhanced the systemic antitumor immune responses and established an optimal immunotherapy strategy against gastrointestinal cancer.

6.
Cancer Sci ; 2024 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-39155589

RESUMEN

The fundamental role of cells in safeguarding the genome's integrity against DNA double-strand breaks (DSBs) is crucial for maintaining chromatin homeostasis and the overall genomic stability. Aberrant responses to DNA damage, known as DNA damage responses (DDRs), can result in genomic instability and contribute significantly to tumorigenesis. Unraveling the intricate mechanisms underlying DDRs following severe damage holds the key to identify therapeutic targets for cancer. Chromatin lysine acylation, encompassing diverse modifications such as acetylation, lactylation, crotonylation, succinylation, malonylation, glutarylation, propionylation, and butyrylation, has been extensively studied in the context of DDRs and chromatin homeostasis. Here, we delve into the modifying enzymes and the pivotal roles of lysine acylation and their crosstalk in maintaining chromatin homeostasis and genome integrity in response to DDRs. Moreover, we offer a comprehensive perspective and overview of the latest insights, driven primarily by chromatin acylation modification and associated regulators.

7.
J Chem Inf Model ; 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39116039

RESUMEN

AlphaFold 3 (AF3), the latest version of protein structure prediction software, goes beyond its predecessors by predicting protein-protein complexes. It could revolutionize drug discovery and protein engineering, marking a major step toward comprehensive, automated protein structure prediction. However, independent validation of AF3's predictions is necessary. In this work, we evaluate AF3 complex structures using the SKEMPI 2.0 database which involves 317 protein-protein complexes and 8338 mutations. AF3 complex structures when applied to the most advanced TDL model, MT-TopLap (MultiTask-Topological Laplacian), give rise to a very good Pearson correlation coefficient of 0.86 for predicting protein-protein binding free energy changes upon mutation, which is slightly less than the 0.88 achieved earlier with the Protein Data Bank (PDB) structures. Nonetheless, AF3 complex structures led to a 8.6% increase in the prediction RMSE compared to original PDB complex structures. Additionally, some of AF3's complex structures have large errors, which were not captured in its ipTM performance metric. Finally, it is found that AF3's complex structures are not reliable for intrinsically flexible regions or domains.

8.
Artículo en Inglés | MEDLINE | ID: mdl-39117325

RESUMEN

Objectives To compare the gender differences in isolated mitral regurgitation (MR) repair. Methods Of 381 adults aged 54.8±12.3 years undergoing mitral valve repair (MVP) for isolated MR from 01/2019-12/2022, the baseline and operative data, and outcomes were compared between 161 women (42.3%) and 220 men (57.7%). Results Women tended to be non-smoker (98.1% vs 45%, P<0.001), and have more cerebrovascular accidents (38.5% vs 24.1%, P=0.004), lower creatinine (70.0±19.5 vs 86.3±19.9 µmol/dL, P<0.001), smaller LVEDD (54.4±6.7 vs 57.8±6.6 mm, P<0.001) and isolated annular dilatation (19.3% vs 9.1%, P=0.010). One female died of stroke at 2 days (0.3%). Another female (0.3%) underwent MV replacement for failed repair. Stroke occurred in 4 (1.0%). Two underwent re-exploration for bleeding (0.5%). Women were more likely to have less 24-hour drainage (290±143 vs 385±196 mL, P<0.001). Over a mean follow-up of 2.1±1.1 years (100% complete), one woman died, one man underwent a reoperation; 28 had moderate MR, and 9 had severe MR. Neither did early and late mortality and reoperation, nor freedom from late moderate/severe MR (71.6% vs 71.4% at 5 years; P=0.992) differ significantly between two genders. Predictors for late moderate/severe MR were anterior leaflet prolapse (hazard ratio [HR] 4.45; 95% confidence interval [CI] 1.18-16.72; P=0.027) and isolated annular dilation (HR 5.47, 95% CI 1.29-23.25; P=0.021). Conclusions Despite significant differences in smoking, cerebrovascular accidents, creatinine, LVEDD, and isolated annular dilatation at baseline, and 24-hour drainage, women and men did not show significant difference in early and late survival, reoperation and freedom from late moderate/severe MR.

9.
iScience ; 27(6): 110014, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38947512

RESUMEN

The NAD+-dependent deacetylase SIRT7 is a pivotal regulator of DNA damage response (DDR) and a promising drug target for developing cancer therapeutics. However, limited progress has been made in SIRT7 modulator discovery. Here, we applied peptide-based deacetylase platforms for SIRT7 enzymatic evaluation and successfully identified a potent SIRT7 inhibitor YZL-51N. We initially isolated bioactive YZL-51N from cockroach (Periplaneta americana) extracts and then developed the de novo synthesis of this compound. Further investigation revealed that YZL-51N impaired SIRT7 enzymatic activities through occupation of the NAD+ binding pocket. YZL-51N attenuated DNA damage repair induced by ionizing radiation (IR) in colorectal cancer cells and exhibited a synergistic anticancer effect when used in combination with etoposide. Overall, our study not only identified YZL-51N as a selective SIRT7 inhibitor from insect resources, but also confirmed its potential use in combined chemo-radiotherapy by interfering in the DNA damage repair process.

10.
ArXiv ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38947927

RESUMEN

Data sets with imbalanced class sizes, often where one class size is much smaller than that of others, occur extremely often in various applications, including those with biological foundations, such as drug discovery and disease diagnosis. Thus, it is extremely important to be able to identify data elements of classes of various sizes, as a failure to detect can result in heavy costs. However, many data classification algorithms do not perform well on imbalanced data sets as they often fail to detect elements belonging to underrepresented classes. In this paper, we propose the BTDT-MBO algorithm, incorporating Merriman-Bence-Osher (MBO) techniques and a bidirectional transformer, as well as distance correlation and decision threshold adjustments, for data classification problems on highly imbalanced molecular data sets, where the sizes of the classes vary greatly. The proposed method not only integrates adjustments in the classification threshold for the MBO algorithm in order to help deal with the class imbalance, but also uses a bidirectional transformer model based on an attention mechanism for self-supervised learning. Additionally, the method implements distance correlation as a weight function for the similarity graph-based framework on which the adjusted MBO algorithm operates. The proposed model is validated using six molecular data sets, and we also provide a thorough comparison to other competing algorithms. The computational experiments show that the proposed method performs better than competing techniques even when the class imbalance ratio is very high.

11.
Front Cardiovasc Med ; 11: 1383217, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39026999

RESUMEN

Background: Angiotensin II receptor blockers (ARBs) are utilized for the management of hypertension and diabetes. Previous meta-analyses suggested that azilsartan medoxomil (AZL-M) improved blood pressure (BP) reduction, but there were no safety findings or suggestions for patients with hypertension or diabetes. Methods: We performed an efficacy and safety meta-analysis of randomized controlled trials (RCTs) evaluating AZL-M therapy for reducing BP in patients with hypertension. Patients with hypertension complicated by diabetes were analyzed. The relevant literature was searched in English and Chinese databases for RCTs involving AZL-M in hypertension. Efficacy variables included the change from baseline in the 24-h mean systolic/diastolic BP measured by ambulatory BP monitoring, the change from baseline in clinic systolic/diastolic BP, and responder rates. Safety variables included total adverse events (AEs), serious AEs, AEs leading to discontinuation, and AEs related to the study drug. The raw data from the included studies were utilized to calculate the odds ratio (OR) for dichotomous data and the mean difference (MD) for continuous data, accompanied by 95% confidence intervals (CIs). Statistical analysis was performed using R software. Results: A total of 11 RCTs met the inclusion criteria, representing 7,608 patients, 5 of whom had diabetes. Pooled analysis suggested a reduction in BP among patients randomized to 40 mg of AZL-M vs. control therapy [24-h ambulatory blood pressure monitoring (ABPM) mean systolic blood pressure (SBP) (MD: -2.85 mmHg), clinic SBP (MD: -3.48 mmHg), and clinic diastolic blood pressure (DBP) (MD: -1.96 mmHg)] and for 80 mg of AZL-M vs. control therapy [24-h ABPM mean SBP (MD: -3.59 mmHg), 24-h ABPM mean DBP (MD: -2.62 mmHg), clinic SBP (MD: -4.42 mmHg), clinic DBP (MD: -3.09 mmHg), and responder rate (OR: 1.46)]. There was no difference in the reduction of risks, except for dizziness (OR: 1.56) in the 80-mg AZL-M group or urinary tract infection (OR: 1.82) in the 40-mg AZL-M group. Analysis of patients with diabetes revealed that AZL-M can provide superior management, while safety and tolerability were similar to those of control therapy. Conclusions: AZL-M appears to reduce BP to a greater extent than dose-control therapy and does not increase the risk of adverse events in patients with hypertension and diabetes compared with placebo. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=464284, identifier PROSPERO CRD42023464284.

12.
Front Cell Infect Microbiol ; 14: 1408388, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38988810

RESUMEN

Background: Surgical site infection (SSI) is a common complication in HIV-positive fracture patients undergoing surgery, leading to increased morbidity, mortality, and healthcare costs. Accurate prediction of SSI risk can help guide clinical decision-making and improve patient outcomes. However, there is a lack of user-friendly, Web-based calculator for predicting SSI risk in this patient population. Objective: This study aimed to develop and validate a novel web-based risk calculator for predicting SSI in HIV-positive fracture patients undergoing surgery in China. Method: A multicenter retrospective cohort study was conducted using data from HIV-positive fracture patients who underwent surgery in three tertiary hospitals in China between May 2011 and September 2023. We used patients from Beijing Ditan Hospital as the training cohort and patients from Chengdu Public Health and Changsha First Hospital as the external validation cohort. Univariate, multivariate logistic regression analyses and SVM-RFE were performed to identify independent risk factors for SSIs. A web-based calculator was developed using the identified risk factors and validated using an external validation cohort. The performance of the nomogram was evaluated using the area under the receiver operating characteristic (AUC) curves, calibration plots, and decision curve analysis (DCA). Results: A total of 338 HIV-positive patients were included in the study, with 216 patients in the training cohort and 122 patients in the validation cohort. The overall SSI incidence was 10.7%. The web-based risk calculator (https://sydtliubo.shinyapps.io/DynNom_for_SSI/) incorporated six risk factors: HBV/HCV co-infection, HIV RNA load, CD4+ T-cell count, Neu and Lym level. The nomogram demonstrated good discrimination, with an AUC of 0.890 in the training cohort and 0.853 in the validation cohort. The calibration plot showed good agreement between predicted and observed SSI probabilities. The DCA indicated that the nomogram had clinical utility across a wide range of threshold probabilities. Conclusion: Our study developed and validated a novel web-based risk calculator for predicting SSI risk in HIV-positive fracture patients undergoing surgery in China. The nomogram demonstrated good discrimination, calibration, and clinical utility, and can serve as a valuable tool for risk stratification and clinical decision-making in this patient population. Future studies should focus on integrating this nomogram into hospital information systems for real-time risk assessment and management.


Asunto(s)
Infecciones por VIH , Internet , Infección de la Herida Quirúrgica , Humanos , Masculino , China/epidemiología , Femenino , Persona de Mediana Edad , Infecciones por VIH/complicaciones , Estudios Retrospectivos , Factores de Riesgo , Infección de la Herida Quirúrgica/epidemiología , Adulto , Medición de Riesgo/métodos , Curva ROC , Nomogramas
13.
Bioessays ; : e2400107, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38990077

RESUMEN

Post-transcriptional tRNA modifications contribute to the decoding efficiency of tRNAs by supporting codon recognition and tRNA stability. Recent work shows that the molecular and cellular functions of tRNA modifications and tRNA-modifying-enzymes are linked to brain development and neurological disorders. Lack of these modifications affects codon recognition and decoding rate, promoting protein aggregation and translational stress response pathways with toxic consequences to the cell. In this review, we discuss the peculiarity of local translation in neurons, suggesting a role for fine-tuning of translation performed by tRNA modifications. We provide several examples of tRNA modifications involved in physiology and pathology of the nervous system, highlighting their effects on protein translation and discussing underlying mechanisms, like the unfolded protein response (UPR), ribosome quality control (RQC), and no-go mRNA decay (NGD), which could affect neuronal functions. We aim to deepen the understanding of the roles of tRNA modifications and the coordination of these modifications with the protein translation machinery in the nervous system.

14.
Foods ; 13(14)2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39063356

RESUMEN

Against the backdrop of global warming, intensifying regional conflicts, deglobalization, and the spread of diseases, global food security is facing severe challenges. Studying the food security situation in China and the United States in depth can provide practical experience for formulating food security policies for countries around the world and promoting global food security governance. On the basis of a meticulous review of the evolving connotations of food security, this study adopts six dimensions-quantity security, quality security, circulation security, economic security, ecological resource security, and policy security-as breakthrough points to construct a framework consisting of food security evaluation indicator system comprising 29 specific indicators. The CRITIC-MEREC-MARCOS model is applied to evaluate the status of food security in China and the United States from 2000 to 2022, while the obstacle degree model (ODM) model is utilized to identify factors impeding food security between the two countries. The results indicate that the level of food security in China has shown slight fluctuations initially, followed by a steady upward trend. The gap with the United States is continuously narrowing. However, significant differences between China and the United States still exist in terms of economic security, ecological resource security, and policy security. Furthermore, due to the limited productivity of agricultural labor, scarcity of water and soil resources, and low efficiency in the use of fertilizers and pesticides, China's food security is subject to economic and environmental constraints. The restrictions imposed by economic security and ecological resource security on China's food security are showing an increasing trend year by year. For the United States, with the obstruction of grain exports and the increasing frequency of drought disasters, the impact of circulation security and ecological resource security on food security is becoming increasingly prominent. In the future, China and the United States should join hands to address challenges, actively promote international cooperation in food security, and drive sustainable development for humanity.

16.
Sci Rep ; 14(1): 17443, 2024 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-39075190

RESUMEN

Gliomas are the most common malignant tumors of the central nervous system, accounting for approximately 80% of all malignant brain tumors. Accumulating evidence suggest that pyroptosis plays an essential role in the progression of cancer. Unfortunately, the effect of the pyroptosis-related factor caspase-4 (CASP4) on immunotherapy and drug therapy for tumors has not been comprehensively investigated. In this study, we systematically screened six hub genes by pooling differential pyroptosis-related genes in The Cancer Genome Atlas (TCGA) glioma data and the degree of centrality of index-related genes in the protein-protein interaction network. We performed functional and pathway enrichment analyses of the six hub genes to explore their biological functions and potential molecular mechanisms. We then investigated the importance of CASP4 using Kaplan-Meier survival analysis of glioma patients. TCGA and the Chinese Glioma Genome Atlas (CGGA) databases showed that reduced CASP4 expression leads to the potent clinical deterioration of glioma patients. Computational analysis of the effect of CASP4 on the infiltration level and recruitment of glioma immune cells revealed that CASP4 expression was closely associated with a series of tumor-suppressive immune checkpoint molecules, chemokines, and chemokine receptors. We also found that aberrant CASP4 expression correlated with chemotherapeutic drug sensitivity. Finally, analysis at the cellular and tissue levels indicated an increase in CASP4 expression in glioma, and that CASP4 inhibition significantly inhibited the proliferation of glioma cells. Thus, CASP4 is implicated as a new prognostic biomarker for gliomas with the potential to further guide immunotherapy and chemotherapy strategies for glioma patients.


Asunto(s)
Neoplasias Encefálicas , Caspasas Iniciadoras , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Glioma , Humanos , Glioma/genética , Glioma/patología , Glioma/inmunología , Pronóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/mortalidad , Caspasas Iniciadoras/metabolismo , Caspasas Iniciadoras/genética , Piroptosis/genética , Mapas de Interacción de Proteínas , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Estimación de Kaplan-Meier , Línea Celular Tumoral
17.
Front Microbiol ; 15: 1444678, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39040902

RESUMEN

[This corrects the article DOI: 10.3389/fmicb.2022.1001750.].

18.
Sci Rep ; 14(1): 12667, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38831094

RESUMEN

The glutenite reservoir in an exploration area in eastern China is well-developed and holds significant exploration potential as an important oil and gas alternative layer. However, due to the influence of sedimentary characteristics, the glutenite reservoir exhibits strong lateral heterogeneity, significant vertical thickness variations, and low accuracy in reservoir space characterization, which affects the reasonable and effective deployment of development wells. Seismic data contains the three-dimensional spatial characteristics of geological bodies, but how to design a suitable transfer function to extract the nonlinear relationship between seismic data and reservoirs is crucial. At present, the transfer functions are concentrated in low-dimensional or high-dimensional fixed mathematical models, which cannot accurately describe the nonlinear relationship between seismic data and complex reservoirs, resulting in low spatial description accuracy of complex reservoirs. In this regard, this paper first utilizes a fusion method based on probability kernel to fuse seismic attributes such as wave impedance, effective bandwidth, and composite envelope difference. This provide a more intuitive reflection of the distribution characteristics of glutenite reservoirs. Moreover, a hybrid nonlinear transfer function is established to transform the fused attribute cube into an opaque attribute cube. Finally, the illumination model and ray casting method are used to perform voxel imaging of the glutenite reservoirs, brighten the detailed characteristics of reservoir space, and then form a set of methods for ' brightening reservoirs and darkening non-reservoirs ', which improves the spatial engraving accuracy of glutenite reservoirs.

19.
Sci Rep ; 14(1): 14559, 2024 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-38914616

RESUMEN

Understanding the nitrogen isotopic variations of individual amino acids (AAs) is essential for utilizing the nitrogen isotope values of individual amino acids (δ15N-AA) as source indicators to identify proteinaceous matter originating from biomass combustion processes. However, the nitrogen isotope effects (ε) associated with the degradation of individual amino acids during combustion processes have not been previously explored. In this study, we measured the nitrogen isotope values of residual free amino acids -following a series of controlled combustion experiments at temperatures of 160-240 °C and durations of 2 min to 8 h, as described in Part 1. δ15N values of proline, aspartate, alanine, valine, glycine, leucine, and isoleucine are more positive than their initial δ15N values after prolonged combustion. Variations in δ15N values of the most AAs conform to the Rayleigh fractionation during combustion and their nitrogen isotope effects (ε) are greatly impacted by their respective combustion degradation pathways. This is the first time the ε values associated with the degradation pathways of AAs during combustion have been characterized. Only the ε values associated with Pathway 1 (dehydration to form dipeptide) and 2 (simultaneous deamination and decarboxylation) are found to be significant and temperature-dependent, ranging from + 2.9 to 6.4‰ and + 0.9‰ to + 3.8‰, respectively. Conversely, ε values associated with other pathways are minor. This improves the current understanding on the degradation mechanisms of protein nitrogen during biomass burning.


Asunto(s)
Aminoácidos , Isótopos de Nitrógeno , Aminoácidos/metabolismo , Isótopos de Nitrógeno/análisis , Cinética , Biomasa , Temperatura
20.
BMC Plant Biol ; 24(1): 596, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38914948

RESUMEN

BACKGROUND: Cliffs are recognized as one of the most challenging environments for plants, characterized by harsh conditions such as drought, infertile soil, and steep terrain. However, they surprisingly host ancient and diverse plant communities and play a crucial role in protecting biodiversity. The Taihang Mountains, which act as a natural boundary in eastern China, support a rich variety of plant species, including many unique to cliff habitats. However, it is little known how cliff plants adapt to harsh habitats and the demographic history in this region. RESULTS: To better understand the demographic history and adaptation of cliff plants in this area, we analyzed the chromosome-level genome of a representative cliff plant, T. rupestris var. ciliata, which has a genome size of 769.5 Mb, with a scaffold N50 of 104.92 Mb. The rapid expansion of transposable elements may have contributed to the increasing genome and its ability to adapt to unique and challenging cliff habitats. Comparative analysis of the genome evolution between Taihangia and non-cliff plants in Rosaceae revealed a significant expansion of gene families associated with oxidative phosphorylation, which is likely a response to the abiotic stresses faced by cliff plants. This expansion may explain the long-term adaptation of Taihangia to harsh cliff environments. The effective population size of the two varieties has continuously decreased due to climatic fluctuations during the Quaternary period. Furthermore, significant differences in gene expression between the two varieties may explain the varied leaf phenotypes and adaptations to harsh conditions in different natural distributions. CONCLUSION: Our study highlights the extraordinary adaptation of T. rupestris var. ciliata, shedding light on the evolution of cliff plants worldwide.


Asunto(s)
Adaptación Fisiológica , Cromosomas de las Plantas , Genoma de Planta , China , Cromosomas de las Plantas/genética , Adaptación Fisiológica/genética , Rosaceae/genética , Rosaceae/fisiología , Ecosistema , Evolución Molecular
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