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1.
Nature ; 628(8009): 887-893, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38538796

ABSTRACT

Efficient termination is required for robust gene transcription. Eukaryotic organisms use a conserved exoribonuclease-mediated mechanism to terminate the mRNA transcription by RNA polymerase II (Pol II)1-5. Here we report two cryogenic electron microscopy structures of Saccharomyces cerevisiae Pol II pre-termination transcription complexes bound to the 5'-to-3' exoribonuclease Rat1 and its partner Rai1. Our structures show that Rat1 displaces the elongation factor Spt5 to dock at the Pol II stalk domain. Rat1 shields the RNA exit channel of Pol II, guides the nascent RNA towards its active centre and stacks three nucleotides at the 5' terminus of the nascent RNA. The structures further show that Rat1 rotates towards Pol II as it shortens RNA. Our results provide the structural mechanism for the Rat1-mediated termination of mRNA transcription by Pol II in yeast and the exoribonuclease-mediated termination of mRNA transcription in other eukaryotes.


Subject(s)
Cryoelectron Microscopy , Exoribonucleases , RNA Polymerase II , RNA, Messenger , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae , Transcription Termination, Genetic , Exoribonucleases/chemistry , Exoribonucleases/metabolism , Exoribonucleases/ultrastructure , Models, Molecular , Protein Binding , RNA Polymerase II/chemistry , RNA Polymerase II/metabolism , RNA Polymerase II/ultrastructure , RNA, Messenger/biosynthesis , RNA, Messenger/chemistry , RNA, Messenger/genetics , RNA, Messenger/ultrastructure , RNA-Binding Proteins/chemistry , RNA-Binding Proteins/metabolism , RNA-Binding Proteins/ultrastructure , Saccharomyces cerevisiae/chemistry , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae/ultrastructure , Saccharomyces cerevisiae Proteins/chemistry , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae Proteins/ultrastructure , Transcriptional Elongation Factors/chemistry , Transcriptional Elongation Factors/metabolism , Transcriptional Elongation Factors/ultrastructure , Chromosomal Proteins, Non-Histone/chemistry , Chromosomal Proteins, Non-Histone/metabolism , Chromosomal Proteins, Non-Histone/ultrastructure , Protein Domains , RNA, Fungal/biosynthesis , RNA, Fungal/chemistry , RNA, Fungal/genetics , RNA, Fungal/ultrastructure
2.
Nature ; 613(7945): 783-789, 2023 01.
Article in English | MEDLINE | ID: mdl-36631609

ABSTRACT

Efficient and accurate termination is required for gene transcription in all living organisms1,2. Cellular RNA polymerases in both bacteria and eukaryotes can terminate their transcription through a factor-independent termination pathway3,4-called intrinsic termination transcription in bacteria-in which RNA polymerase recognizes terminator sequences, stops nucleotide addition and releases nascent RNA spontaneously. Here we report a set of single-particle cryo-electron microscopy structures of Escherichia coli transcription intrinsic termination complexes representing key intermediate states of the event. The structures show how RNA polymerase pauses at terminator sequences, how the terminator RNA hairpin folds inside RNA polymerase, and how RNA polymerase rewinds the transcription bubble to release RNA and then DNA. These macromolecular snapshots define a structural mechanism for bacterial intrinsic termination and a pathway for RNA release and DNA collapse that is relevant for factor-independent termination by all RNA polymerases.


Subject(s)
DNA, Bacterial , DNA-Directed RNA Polymerases , Escherichia coli , RNA, Bacterial , Transcription Termination, Genetic , Cryoelectron Microscopy , DNA-Directed RNA Polymerases/chemistry , DNA-Directed RNA Polymerases/metabolism , DNA-Directed RNA Polymerases/ultrastructure , Escherichia coli/chemistry , Escherichia coli/genetics , Escherichia coli/metabolism , Escherichia coli/ultrastructure , RNA, Bacterial/chemistry , RNA, Bacterial/genetics , RNA, Bacterial/metabolism , RNA, Bacterial/ultrastructure , Terminator Regions, Genetic/genetics , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Bacterial/metabolism , DNA, Bacterial/ultrastructure
3.
Plant Cell ; 35(10): 3641-3661, 2023 09 27.
Article in English | MEDLINE | ID: mdl-37453082

ABSTRACT

DNA-dependent RNA polymerases (Pols) transfer the genetic information stored in genomic DNA to RNA in all organisms. In eukaryotes, the typical products of nuclear Pol I, Pol II, and Pol III are ribosomal RNAs, mRNAs, and transfer RNAs, respectively. Intriguingly, plants possess two additional Pols, Pol IV and Pol V, which produce small RNAs and long noncoding RNAs, respectively, mainly for silencing transposable elements. The five plant Pols share some subunits, but their distinct functions stem from unique subunits that interact with specific regulatory factors in their transcription cycles. Here, we summarize recent advances in our understanding of plant nucleus-localized Pols, including their evolution, function, structures, and transcription cycles.


Subject(s)
DNA-Directed RNA Polymerases , Plants , DNA-Directed RNA Polymerases/genetics , DNA-Directed RNA Polymerases/metabolism , Plants/genetics , Plants/metabolism , RNA Polymerase II/genetics , DNA , DNA Methylation
4.
Cancer Immunol Immunother ; 73(9): 171, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38954021

ABSTRACT

In the intricate landscape of the tumor microenvironment, tumor-associated macrophages (TAMs) emerge as a ubiquitous cellular component that profoundly affects the oncogenic process. The microenvironment of hepatocellular carcinoma (HCC) is characterized by a pronounced infiltration of TAMs, underscoring their pivotal role in modulating the trajectory of the disease. Amidst the evolving therapeutic paradigms for HCC, the strategic reprogramming of metabolic pathways presents a promising avenue for intervention, garnering escalating interest within the scientific community. Previous investigations have predominantly focused on elucidating the mechanisms of metabolic reprogramming in cancer cells without paying sufficient attention to understanding how TAM metabolic reprogramming, particularly lipid metabolism, affects the progression of HCC. In this review article, we intend to elucidate how TAMs exert their regulatory effects via diverse pathways such as E2F1-E2F2-CPT2, LKB1-AMPK, and mTORC1-SREBP, and discuss correlations of TAMs with these processes and the characteristics of relevant pathways in HCC progression by consolidating various studies on TAM lipid uptake, storage, synthesis, and catabolism. It is our hope that our summary could delineate the impact of specific mechanisms underlying TAM lipid metabolic reprogramming on HCC progression and provide useful information for future research on HCC and the development of new treatment strategies.


Subject(s)
Carcinoma, Hepatocellular , Lipid Metabolism , Liver Neoplasms , Tumor Microenvironment , Tumor-Associated Macrophages , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/immunology , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Tumor-Associated Macrophages/metabolism , Tumor-Associated Macrophages/immunology , Tumor Microenvironment/immunology , Animals , Cellular Reprogramming , Signal Transduction , Metabolic Reprogramming
5.
Breast Cancer Res Treat ; 206(1): 45-56, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38616207

ABSTRACT

PURPOSE: The significance of postmastectomy radiotherapy (PMRT) in breast cancer patients who initially have clinically node-positive (cN +) status but achieve downstaging to ypN0 following neoadjuvant chemotherapy (NAC) remains uncertain. This study aims to assess the impact of PMRT in this patient subset. METHODS: Patients were enrolled from West China Hospital, Sichuan University from 2008 to 2019. Overall survival (OS), Locoregional recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), and breast cancer-specific survival (BCSS) were estimated using the Kaplan-Meier method and assessed with the log-rank test. The impact of PMRT was further analyzed by the Cox proportional hazards model. Propensity score matching (PSM) was performed to reduce the selection bias. RESULTS: Of the 333 eligible patients, 189 (56.8%) received PMRT, and 144 (43.2%) did not. At a median follow-up period of 71 months, the five-year LRFS, DMFS, BCSS, and OS rates were 99.1%, 93.4%, 96.4%, and 94.3% for the entire cohort, respectively. Additionally, the 5-year LRFS, DMFS, BCSS, and OS rates were 98.9%, 93.8%, 96.7%, and 94.5% with PMRT and 99.2%, 91.3%, 94.9%, and 92.0% without PMRT, respectively (all p-values not statistically significant). After multivariate analysis, PMRT was not a significant risk factor for any of the endpoints. When further stratified by stage, PMRT did not show any survival benefit for patients with stage II-III diseases. CONCLUSION: In the context of comprehensive treatments, PMRT might be exempted in ypN0 breast cancer patients. Further large-scale, randomized controlled studies are required to investigate the significance of PMRT in this patient subset.


Subject(s)
Breast Neoplasms , Mastectomy , Neoadjuvant Therapy , Neoplasm Staging , Humans , Female , Breast Neoplasms/pathology , Breast Neoplasms/therapy , Breast Neoplasms/mortality , Breast Neoplasms/drug therapy , Breast Neoplasms/radiotherapy , Middle Aged , Neoadjuvant Therapy/methods , Adult , Aged , Retrospective Studies , Radiotherapy, Adjuvant/methods , Chemotherapy, Adjuvant/methods , Lymphatic Metastasis , Neoplasm Recurrence, Local/pathology
6.
Biomed Microdevices ; 26(2): 20, 2024 Mar 02.
Article in English | MEDLINE | ID: mdl-38430318

ABSTRACT

Polymerase chain reaction (PCR) has been considered as the gold standard for detecting nucleic acids. The simple PCR system is of great significance for medical applications in remote areas, especially for the developing countries. Herein, we proposed a low-cost self-assembled platform for microchamber PCR. The working principle is rotating the chamber PCR microfluidic chip between two heaters with fixed temperature to solve the problem of low temperature variation rate. The system consists of two temperature controllers, a screw slide rail, a chamber array microfluidic chip and a self-built software. Such a system can be constructed at a cost of about US$60. The micro chamber PCR can be finished by rotating the microfluidic chip between two heaters with fixed temperature. Results demonstrated that the sensitivity of the temperature controller is 0.1℃. The relative error of the duration for the microfluidic chip was 0.02 s. Finally, we successfully finished amplification of the target gene of Porphyromonas gingivalis in the chamber PCR microfluidic chip within 35 min and on-site detection of its PCR products by fluorescence. The chip consisted of 3200 cylindrical chambers. The volume of reagent in each volume is as low as 0.628 nL. This work provides an effective method to reduce the amplification time required for micro chamber PCR.


Subject(s)
Microfluidics , Microfluidics/methods , Temperature , Oligonucleotide Array Sequence Analysis/methods , Polymerase Chain Reaction/methods
7.
Environ Sci Technol ; 2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38316131

ABSTRACT

China's online food delivery (OFD) services consume enormous amounts of disposable plastics. Here, we investigated and modeled the national mass inventories and environmental release of plastics and chemical additives in the plastic. The extra-tree regression identified six key descriptors in determining OFD sales in Chinese cities. Approximately 847 kt of OFD plastic waste was generated in 2021 (per capita 1.10 kg/yr in the megacities and 0.39 kg/yr in other cities). Various additives were extensively detected, with geomean concentrations of 140.96, 4.76, and 0.25 µg/g for ∑8antioxidants, ∑21phthalates, and bisphenol A (BPA), respectively. The estimated mass inventory of these additives in the OFD plastics was 164.7 t, of which 51.1 t was released into the atmosphere via incineration plants and 51.0 t was landfilled. The incineration also released 8.07 t of polycyclic aromatic hydrocarbons and 39.1 kt of particulate matter into the atmosphere. Takeout food may increase the dietary intake of phthalates and BPA by 30% to 50% and raise concerns about considerable exposure to antioxidant transformation products. This study provides profound environmental implications for plastic waste in the Chinese OFD industry. We call for a sustainable circular economy action plan for waste disposal, but mitigating the hazardous substance content and their emissions is urgent.

8.
Acta Pharmacol Sin ; 2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39085407

ABSTRACT

Tumor immunotherapy characterized by its high specificity and minimal side effects has achieved revolutionary progress in the field of cancer treatment. However, the complex mechanisms of tumor immune microenvironment (TIME) and the individual variability of patients' immune system still present significant challenges to its clinical application. Immunocyte membrane-coated nanocarrier systems, as an innovative biomimetic drug delivery platform, exhibit remarkable advantages in tumor immunotherapy due to their high targeting capability, good biocompatibility and low immunogenicity. In this review we summarize the latest research advances in biomimetic delivery systems based on immune cells for tumor immunotherapy. We outline the existing methods of tumor immunotherapy including immune checkpoint therapy, adoptive cell transfer therapy and cancer vaccines etc. with a focus on the application of various immunocyte membranes in tumor immunotherapy and their prospects and challenges in drug delivery and immune modulation. We look forward to further exploring the application of biomimetic delivery systems based on immunocyte membrane-coated nanoparticles, aiming to provide a new framework for the clinical treatment of tumor immunity.

9.
Environ Res ; 252(Pt 3): 119059, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38701891

ABSTRACT

Recent studies revealed the un-negligible impact of airborne organophosphate esters (OPEs) on phosphorus (P)-limited ecosystems. Subtropical forests, the global prevalence P-limited ecosystems, contain canopy structures that can effectively sequester OPEs from the atmosphere. However, little is known about the behavior and fate of OPEs in subtropical forest ecosystem, and the impact on the P cycling in this ecosystem. OPE concentrations in the understory air (at two heights), foliage, and litterfall were investigated in a subtropical forest in southern China. The median ∑OPE concentrations were 3149 and 2489 pg/m3 in the upper and bottom air, respectively. Foliage exhibited higher ∑OPE concentrations (median = 386 ng/g dry weight (dw)) compared to litter (median = 267 ng/g dw). The air OPE concentrations were ordered by broadleaved forest > mixed forest > coniferous forest, which corresponds to the results of canopy coverage or leaf area index. The spatial variation of OPEs in foliage and litter was likely caused by the leaf surface functional traits. Higher OPE concentrations were found in the wet season for understory air while in the dry season for foliage and litter, which were attributed to the changes in emission sources and meteorological conditions, respectively. The inverse temporal variation suggests the un-equilibrium partitioning of OPEs between leaf and air. The OPE concentrations during the litter-incubation presented similar temporal trends with those in foliage and litter, indicating the strong interaction of OPEs between the litter layer and the near-soil air, and the efficient buffer of litter layer played in the OPEs partitioning between soil and air. The median OPEs-associated P deposition fluxes through litterfall were 270, 186, and 249 µg P/m2·yr in the broadleaved, mixed, and coniferous forests, respectively. Although the fluxes accounted for approximately 0.2% of the total atmospheric P deposition, their significance to this P-limited ecosystem may not be negligible.


Subject(s)
Air Pollutants , Environmental Monitoring , Forests , Plant Leaves , China , Plant Leaves/chemistry , Air Pollutants/analysis , Organophosphates/analysis , Esters/analysis , Seasons , Spatio-Temporal Analysis , Trees
10.
Environ Res ; 250: 118554, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38417657

ABSTRACT

Accurate prediction and measurement of yield stress are crucial for optimizing sludge treatment and disposal. However, the differences and applicability of various methods for measuring yield stress are subjects of ongoing debate. Meanwhile, literature on measuring sludge yield stress is limited to low solid concentrations (TS <10%), understanding and studying the yield stress of medium to high solid concentration sludge is crucial due to increasingly stringent standards for sludge treatment and disposal. So, this study employed a rotational rheometer to measure sludge yield stress across a wide range of TS (4-50%) using steady shear, dynamic oscillatory shear, and transient shear. The study derived significant conclusions by comparing and summarizing the applicability and limitations of each testing method: Dynamic oscillatory shear methods, including G'-σ curve method, γ-σ curve method, and G**γc method can measure sludge yield stress ranging from 4% to 40% TS, while other methods are restricted to low or limited solid concentrations; The G' = G″ method, utilizing the intersection of G' and G″ curves, consistently yields the highest value for yield stress when 4%≤ TS ≤ 12%; The rotational rheometer cannot measure sludge yield stress when the solid concentration exceeds 40% TS; The relationship between sludge yield stress and solid concentration is stronger as a power-law for TS ≤ 25%, transitioning to linear for higher concentrations (28%≤ TS <40%). This study systematically explores the applicability and limitations of various measurement methods for characterizing sludge yield stress across a wide range of solid concentrations, providing valuable guidance for scientific measurement and highlighting challenging research issues.


Subject(s)
Sewage , Rheology/methods , Waste Disposal, Fluid/methods
11.
Environ Toxicol ; 39(4): 2032-2042, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38095090

ABSTRACT

Diphenyl phosphate (DPhP) is one of the frequently used derivatives of aryl phosphate esters and is used as a plasticizer in industrial production. Like other plasticizers, DPhP is not chemically bound and can easily escape into the environment, thereby affecting human health. DPhP has been associated with developmental toxicity, reproductive toxicity, neurodevelopmental toxicity, and interference with thyroid homeostasis. However, understanding of the underlying mechanism of DPhP on the reproductive toxicity of GC-2spd(ts) cells remains limited. For the first time, we investigated the effect of DPhP on GC-2spd(ts) cell apoptosis. By decreasing nuclear factor erythroid-derived 2-related factor (Nrf2)/p53 signaling, DPhP inhibited autophagy and promoted apoptosis. DPhP reduced total antioxidant capacity and nuclear Nrf2 and its downstream target gene expression. In addition, we investigated the protective effects of Curcumin (Cur) against DPhP toxicity. Cur attenuated the DPhP-induced rise in p53 expression while increasing Nrf2 expression. Cur inhibited DPhP-induced apoptosis in GC-2spd(ts) cells by activating autophagy via Nrf2/p53 signaling. In conclusion, our study provides new insights into the reproductive toxicity hazards of DPhP and demonstrates that Cur is an important therapeutic agent for alleviating DPhP-induced reproductive toxicity by regulating Nrf2/p53 signaling.


Subject(s)
Biphenyl Compounds , Curcumin , Humans , Curcumin/pharmacology , NF-E2-Related Factor 2/metabolism , Tumor Suppressor Protein p53/metabolism , Phosphates/metabolism , Phosphates/pharmacology , Apoptosis , Plasticizers , Autophagy
12.
Ren Fail ; 46(2): 2387205, 2024 Dec.
Article in English | MEDLINE | ID: mdl-39120130

ABSTRACT

BACKGROUND: To compare the impact of tunneled cuffed catheters (TCCs) and arteriovenous fistulas (AVFs) on outcomes in elderly hemodialysis (HD) patients. METHODS: A retrospective matched cohort study was performed. Propensity score matching (PSM) was applied to balance the baseline conditions, and we compared all-cause mortality, major adverse cardiovascular and cerebrovascular events (MACCEs), hospitalization, and infection rates between AVF and TCC patients ≥70 years old. Cox survival analysis was used to analyze the risk factors for death. RESULTS: There were 2119 patients from our center in the Chinese National Renal Data System (CNRDS) between 1 January 2010 and 10 October 2023. Among these patients, 77 TCC patients were matched with 77 AVF patients. There was no significant difference in all-cause mortality between the TCC and AVF groups (30.1/100 vs. 33.3/100 patient-years, p = 0.124). Among the propensity score-matched cohorts, no significant differences in Kaplan-Meier curves were observed between the two groups (log-rank p = 0.242). The TCC group had higher rates of MACCEs, hospitalization, and infection than the AVF group (33.7/100 vs. 29.5/100 patient-years, 101.2/100 vs. 79.5/100 patient-years, and 30.1/100 vs. 14.1/100 patient-years, respectively). Multivariate analysis showed that high Charlson comorbidity index (CCI) score was a risk factor for death. CONCLUSIONS: There was no significant difference in all-cause mortality between elderly HD patients receiving TCCs and AVFs. Compared with those with a TCC, elderly HD patients with an AVF have a lower risk of MACCEs, hospitalization, and infection.


Subject(s)
Arteriovenous Shunt, Surgical , Kidney Failure, Chronic , Propensity Score , Renal Dialysis , Humans , Male , Female , Aged , Retrospective Studies , Kidney Failure, Chronic/therapy , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/mortality , Risk Factors , Arteriovenous Shunt, Surgical/adverse effects , Aged, 80 and over , Hospitalization/statistics & numerical data , China/epidemiology , Prognosis , Kaplan-Meier Estimate
13.
J Environ Manage ; 367: 122106, 2024 Aug 06.
Article in English | MEDLINE | ID: mdl-39111006

ABSTRACT

Organophosphate esters (OPEs) serve as significant flame retardants and plasticizers in various petrochemical downstream products. The petrochemical industry could be a potential source of atmospheric OPEs, but their emissions from this industry are poorly understood. The present study revealed the spatial variation, emission, and atmospheric transport of traditional and novel OPEs (TOPEs and NOPEs, respectively) in atmospheric particulate matter (PM) across Hainan and Guangdong petrochemical complexes (HNPC and GDPC, respectively) in southern China. The total concentrations of TOPEs ranged from 232 to 46,002 pg/m3 and from 200 to 20,347 pg/m3 in the HNPC and GDPC, respectively, which were substantially higher than those of NOPEs (HNPC: 23.5-147 pg/m3, GDPC: 13.9-465 pg/m3). Enterprises involved in the production of downstream petrochemical products presented relatively high concentrations of OPEs, indicating evident emissions of these pollutants in the petrochemical industry. The correlations of PM-bound OPEs in the atmosphere are determined mainly by their coaddition to industrial products or their coexistence in technical mixtures. The annual emissions of TOPEs and NOPEs in the HNPC were 42.6 kg and 0.34 kg, respectively, and those in the GDPC were 116 kg and 1.85 kg, respectively. OPEs from the HNPC can reach Vietnam, Cambodia, and Guangxi Province, China, and those from the GDPC can reach Guangxi Province and Hunan Province via atmospheric transmission after 24 h of emission. The OPE concentrations reaching the receptor regions were generally less than 3.20 pg/m3. Risk assessment revealed that OPE inhalation exposure on two petrochemical complexes likely poses minor risks for people living in the study areas, but the risk resulting from two chlorinated OPEs should be noted since they are close to the threshold values. This study has implications for enhancing control measures for OPE emissions to reduce health risks related to the petrochemical industry.

14.
Entropy (Basel) ; 26(3)2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38539713

ABSTRACT

The Kelvin relation, relating the Seebeck coefficient and the Peltier coefficient, is a theoretical basis of thermoelectricity. It was first derived by Kelvin using a quasi-thermodynamic approach. However, Kelvin's approach was subjected to much criticism due to the rude neglect of irreversible factors. It was only later that a seemingly plausible proof of the Kelvin relation was given using the Onsager reciprocal relation with full consideration of irreversibility. Despite this, a critical issue remains. It is believed that the Seebeck and Peltier effects are thermodynamically reversible, and therefore, the Kelvin relation should also be independent of irreversibility. Kelvin's quasi-thermodynamic approach, although seemingly irrational, may well have touched on the essence of thermoelectricity. To avoid Kelvin's dilemma, this study conceives the physical scenarios of equilibrium thermodynamics to explore thermoelectricity. Unlike Kelvin's quasi-thermodynamic approach, here, a completely reversible thermodynamic approach is used to establish the reciprocal relations of thermoelectricity, on the basis of which the Kelvin relation is once again derived. Moreover, a direct thermodynamic derivation of the Onsager reciprocal relations for fluxes defined as the time derivative of an extensive state variable is given using the method of equilibrium thermodynamics. The present theory can be extended to other coupled phenomena.

15.
Entropy (Basel) ; 26(6)2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38920523

ABSTRACT

Bridgman once reflected on thermodynamics that the laws of thermodynamics were formulated in their present form by the great founders of thermodynamics, Kelvin and Clausius, before all the essential physical facts were in, and there has been no adequate reexamination of the fundamentals since. Thermodynamics still has unknown possibilities waiting to be explored. This paper begins with a brief review of Clausius's work on the second law of thermodynamics and a reassessment of the content of Clausius's statement. The review tells that what Clausius originally referred to as the second law of thermodynamics was, in fact, the theorem of equivalence of transformations (TET) in a reversible cycle. On this basis, a new symmetric form of Clausius's TET is proposed. This theorem says that the two transformations, i.e., the transformation of heat to work and the transformation of work from high pressure to low pressure, should be equivalent in a reversible work-to-heat cycle. New thermodynamic cyclic laws are developed on the basis of the cycle with two work reservoirs (two pressures), which enriches the fundamental of the second law of thermodynamics.

16.
J Gene Med ; 25(11): e3551, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37401256

ABSTRACT

BACKGROUND: Hepatocellular carcinoma (HCC) is a malignant disease with a high incidence rate, high mortality and poor prognosis. Neutrophil extracellular traps (NETs), as an extracellular reticular structure, promote the development and progression of cancer in the tumor microenvironment, and have a promising prospect as a prognostic indicator. In the present study, we elucidated the prognostic value of NET-related genes. METHODS: The NETs gene pair of The Cancer Genome Atlas cohort was constructed by least absolute shrinkage and selection operator analysis. Samples from the International Cancer Genome Consortium were performed to verify its feasibility. Kaplan-Meier analysis was used to compare the overall survival (OS) rate of the two subgroups. The independent predictors of OS were determined by univariate and multivariate Cox analysis. Furthermore, Gene Ontology term and Kyoto Encyclopedia of Genes and Genomes pathway were analyzed by gene set enrichment analysis. The single sample gene set enrichment analysis method was performed to deplore the relationship of risk score with tumor immune microenvironment. The GSE149614 dataset was applied as single cell RNA level validation. PCR was performed to the detect mRNA expression profiles of NETs-related genes. RESULTS: Our analysis of the NETs-related model provides a promising prospect as a prognostic indicator. The OS of high-risk group patients was significantly reduced. The risk score was an important independent predictor of HCC prognosis. The Nomogram model suggested a favorable classification performance. The drug resistance and sensitivity of tumor cells to chemotherapeutics was significantly correlated with the prognostic gene expression. The immune status of the two risk groups showed a marked difference. CONCLUSIONS: The novel prognostic gene pair and immune landscape could predict the prognosis of HCC patients and provide a new understanding of immunotherapy in HCC.


Subject(s)
Carcinoma, Hepatocellular , Extracellular Traps , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/diagnosis , Carcinoma, Hepatocellular/genetics , Extracellular Traps/genetics , Liver Neoplasms/genetics , Gene Ontology , Immunotherapy , Tumor Microenvironment/genetics
17.
J Transl Med ; 21(1): 620, 2023 09 12.
Article in English | MEDLINE | ID: mdl-37700323

ABSTRACT

BACKGROUND: A significant proportion of septic patients with acute lung injury (ALI) are recognized late due to the absence of an efficient diagnostic test, leading to the postponed treatments and consequently higher mortality. Identifying diagnostic biomarkers may improve screening to identify septic patients at high risk of ALI earlier and provide the potential effective therapeutic drugs. Machine learning represents a powerful approach for making sense of complex gene expression data to find robust ALI diagnostic biomarkers. METHODS: The datasets were obtained from GEO and ArrayExpress databases. Following quality control and normalization, the datasets (GSE66890, GSE10474 and GSE32707) were merged as the training set, and four machine learning feature selection methods (Elastic net, SVM, random forest and XGBoost) were applied to construct the diagnostic model. The other datasets were considered as the validation sets. To further evaluate the performance and predictive value of diagnostic model, nomogram, Decision Curve Analysis (DCA) and Clinical Impact Curve (CIC) were constructed. Finally, the potential small molecular compounds interacting with selected features were explored from the CTD database. RESULTS: The results of GSEA showed that immune response and metabolism might play an important role in the pathogenesis of sepsis-induced ALI. Then, 52 genes were identified as putative biomarkers by consensus feature selection from all four methods. Among them, 5 genes (ARHGDIB, ALDH1A1, TACR3, TREM1 and PI3) were selected by all methods and used to predict ALI diagnosis with high accuracy. The external datasets (E-MTAB-5273 and E-MTAB-5274) demonstrated that the diagnostic model had great accuracy with AUC value of 0.725 and 0.833, respectively. In addition, the nomogram, DCA and CIC showed that the diagnostic model had great performance and predictive value. Finally, the small molecular compounds (Curcumin, Tretinoin, Acetaminophen, Estradiol and Dexamethasone) were screened as the potential therapeutic agents for sepsis-induced ALI. CONCLUSION: This consensus of multiple machine learning algorithms identified 5 genes that were able to distinguish ALI from septic patients. The diagnostic model could identify septic patients at high risk of ALI, and provide potential therapeutic targets for sepsis-induced ALI.


Subject(s)
Acute Lung Injury , Sepsis , Humans , Consensus , Sepsis/complications , Acetaminophen , Acute Lung Injury/diagnosis , Acute Lung Injury/etiology , Machine Learning , rho Guanine Nucleotide Dissociation Inhibitor beta
18.
Cardiovasc Diabetol ; 22(1): 138, 2023 06 13.
Article in English | MEDLINE | ID: mdl-37312120

ABSTRACT

BACKGROUND: The triglyceride-glucose (TyG) index was significantly associated with insulin resistance (IR). Several studies have validated the effect of TyG index on cerebrovascular disease. However, the value of TyG index in patients with severe stroke requiring ICU admission remains unclear. The aim of this study was to investigate the association between the TyG index and clinical prognosis of critically ill patients with ischemic stroke (IS). METHODS: This study identified patients with severe IS requiring ICU admission from the Medical Information Mart for Intensive Care (MIMIC-IV) database, and divided them into quartiles based on TyG index level. The outcomes included in-hospital mortality and ICU mortality. The association between the TyG index and clinical outcomes in critically ill patients with IS was elucidated using Cox proportional hazards regression analysis and restricted cubic splines. RESULTS: A total of 733 patients (55.8% male) were enrolled. The hospital mortality and intensive care unit (ICU) mortality reached 19.0% and 14.9%, respectively. Multivariate Cox proportional hazards analysis showed that the elevated TyG index was significantly related to all-cause death. After confounders adjusting, patients with an elevated TyG index had a significant association with hospital mortality (adjusted hazard ratio, 1.371; 95% confidence interval, 1.053-1.784; P = 0.013) and ICU mortality (adjusted hazard ratio, 1.653; 95% confidence interval, 1.244-2.197; P = 0.001). Restricted cubic splines revealed that a progressively increasing risk of all-cause mortality was related to an elevated TyG index. CONCLUSION: The TyG index has a significant association with hospital and ICU all-cause death in critically ill patients with IS. This finding demonstrates that the TyG index might be useful in identifying patients with IS at high risk of all-cause death.


Subject(s)
Ischemic Stroke , Stroke , Humans , Male , Female , Critical Illness , Hospital Mortality , Stroke/diagnosis , Stroke/therapy , Glucose
19.
Pediatr Res ; 94(2): 653-659, 2023 08.
Article in English | MEDLINE | ID: mdl-36732647

ABSTRACT

BACKGROUND: The brain and muscle Arnt-like protein-1 (BMAL1) gene is an important circadian clock gene and previous studies have found that certain polymorphisms are associated with type 2 diabetes in adults. However, it remains unknown if such polymorphisms can affect fasting glucose in children and if other factors modify the associations. METHODS: A school-based cross-sectional study with 947 Chinese children was conducted. A multivariable linear regression model was used to analyze the association between BMAL1 gene polymorphisms and fasting glucose level. RESULTS: After adjusting for age, sex, body mass index (BMI), physical activity, and unhealthy diet, GG genotype carriers of BMAL1 rs3789327 had higher fasting glucose than AA/GA genotype carriers (b = 0.101, SE = 0.050, P = 0.045). Adjusting for the same confounders, rs3816358 was shown to be significantly associated with fasting glucose (b = 0.060, SE = 0.028, P = 0.032). Furthermore, a significant interaction between rs3789327 and nutritional status on fasting glucose was identified (Pinteraction = 0.009); rs3789327 was associated with fasting glucose in the overweight/obese subgroup (b = 0.353, SE = 0.126, P = 0.006), but not in non-overweight/non-obese children. CONCLUSIONS: BMAL1 polymorphisms were significantly associated with the fasting glucose level in children. Additionally, the observed interaction between nutritional status and BMAL1 supports promoting an optimal BMI in children genetically predisposed to higher glucose level. IMPACT: Polymorphisms in the essential circadian clock gene BMAL1 were associated with fasting blood glucose levels in children. Additionally, there was a significant interaction between nutritional status and BMAL1 affecting fasting glucose levels. BMAL1 rs3789327 was associated with fasting glucose only in overweight/obese children. This finding could bring novel insights into mechanisms by which nutritional status influences fasting glucose in children.


Subject(s)
Diabetes Mellitus, Type 2 , Adult , Child , Humans , ARNTL Transcription Factors/genetics , Cross-Sectional Studies , Fasting , Glucose , Obesity/genetics , Polymorphism, Single Nucleotide
20.
Physiol Plant ; 175(2): e13903, 2023 Mar.
Article in English | MEDLINE | ID: mdl-37002824

ABSTRACT

Stomatal closure is regulated by plant hormones and some small molecules to reduce water loss under stress conditions. Both abscisic acid (ABA) and polyamines alone induce stomatal closure; however, whether the physiological functions of ABA and polyamines are synergistic or antagonistic with respect to inducing stomatal closure is still unknown. Here, stomatal movement in response to ABA and/or polyamines was tested in Vicia faba and Arabidopsis thaliana, and the change in the signaling components under stomatal closure was analyzed. We found that both polyamines and ABA could induce stomatal closure through similar signaling components, including the synthesis of hydrogen peroxide (H2 O2 ) and nitric oxide (NO) and the accumulation of Ca2+ . However, polyamines partially inhibited ABA-induced stomatal closure both in epidermal peels and in planta by activating antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), to eliminate the ABA-induced increase in H2 O2 . These results strongly indicate that polyamines inhibit abscisic acid-induced stomatal closure, suggesting that polyamines could be used as potential plant growth regulators to increase photosynthesis under mild drought stress.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Abscisic Acid/pharmacology , Hydrogen Peroxide , Polyamines , Plant Stomata/physiology , Plant Growth Regulators , Arabidopsis/physiology
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