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2.
Molecules ; 29(15)2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39125080

ABSTRACT

Organic fluorides are widely used in pharmaceuticals, agrochemicals, material sciences, and other fields due to the special physical and chemical properties of fluorine atoms. The synthesis of alkyl fluorinated compounds bearing multiple contiguous stereogenic centers is the most challenging research area in synthetic chemistry and has received extensive attention from chemists. This review summarized the important research progress in the field over the past decade, including asymmetric electrophilic fluorination and the asymmetric elaboration of fluorinated substrates (such as allylic alkylation reactions, hydrofunctionalization reactions, Mannich addition reactions, Michael addition reactions, aldol addition reactions, and miscellaneous reactions), with an emphasis on synthetic methodologies, substrate scopes, and reaction mechanisms.

3.
Glob Heart ; 19(1): 57, 2024.
Article in English | MEDLINE | ID: mdl-38973986

ABSTRACT

Aim: The information assessing sex differences in outcomes of patients with three-vessel coronary disease (TVD) after different treatment strategies is sparse. This study aimed to investigate long-term outcomes of TVD among women compared with men after medical therapy (MT) alone, percutaneous coronary intervention (PCI), or coronary artery bypass grafting surgery (CABG). Methods: Consecutive 8943 patients with TVD were enrolled. Associations between sex and all-cause death and major adverse cardiac and cerebrovascular events (MACCE) (all-cause death, myocardial infarction, or stroke) were assessed. Results: Of the 8943 patients, 1821 (20.4%) were women. During a median follow-up of 6.6 years, women had comparable incidences of all-cause death (16.6% vs. 14.9%, P = 0.079) and MACCE (27.2% vs. 26.1%, P = 0.320) to men. After multivariable analysis, women showed lower adjusted risks of all-cause death (HR: 0.777; P = 0.001) and MACCE (HR: 0.870; P = 0.016) than men in the entire cohort. Subgroup analysis revealed that the less all-cause death risk of women relative to men was significant in PCI (HR: 0.702; P = 0.009), and CABG groups (HR: 0.708; P = 0.047), but not in MT alone group. Lower MACCE risk for women vs. men was significant only in PCI group (HR: 0.821; P = 0.037). However, no significant interaction between sex and three strategies was observed for all-cause death (P for interaction = 0.312) or MACCE (P for interaction = 0.228). Conclusions: The cardiovascular prognosis of TVD female patients is better than that of men, which has no interaction with the treatment strategies received (MT alone, PCI, or CABG).


Subject(s)
Coronary Artery Bypass , Coronary Artery Disease , Percutaneous Coronary Intervention , Humans , Female , Male , Middle Aged , Percutaneous Coronary Intervention/methods , Coronary Artery Disease/surgery , Coronary Artery Disease/epidemiology , Coronary Artery Disease/therapy , Sex Factors , Coronary Artery Bypass/statistics & numerical data , Aged , Follow-Up Studies , Retrospective Studies , Treatment Outcome , Time Factors , Incidence , Cause of Death/trends , Risk Factors , Survival Rate/trends
4.
Sci Rep ; 14(1): 15851, 2024 07 09.
Article in English | MEDLINE | ID: mdl-38982110

ABSTRACT

The ankle joint, which connects the lower limbs and the sole of the foot, is prone to sprain during walking and sports, which leads to ankle arthritis. Supratroleolar osteotomy is an ankle preserving operation for the treatment of ankle arthritis, in which the osteotomy is an important fixing and supporting part. In order to avoid stress shielding effect as much as possible, the osteotomy block is designed as a porous structure. In this study, the osteotomy block was designed based on three-period minimal surface, and the designed structure was manufactured by 3D printing. The mechanical properties of different structures were studied by mechanical test and finite element simulation. In mechanical tests, the Gyroid structure showed a progressive failure mechanism from bottom to bottom, while the Diamond structure showed a shear failure zone at 45° Angle, which was not conducive to energy absorption and was more prone to brittle fracture than the Gyroid structure. Therefore, the Gyroid structure is valuable for further research in the development of porous osteotomy.


Subject(s)
Finite Element Analysis , Osteotomy , Printing, Three-Dimensional , Osteotomy/methods , Humans , Foot/surgery , Ankle Joint/surgery
5.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 49(3): 417-425, 2024 Mar 28.
Article in English, Chinese | MEDLINE | ID: mdl-38970516

ABSTRACT

OBJECTIVES: Rejection remains the most important factor limiting the survival of transplanted kidneys. Although a pathological biopsy of the transplanted kidney is the gold standard for diagnosing rejection, its limitations prevent it from being used as a routine monitoring method. Recently, peripheral blood lymphocyte subpopulation testing has become an important means of assessing the body's immune system, however, its application value and strategy in the field of kidney transplantation need further exploration. Additionally, the development and utilization of routine test parameters are also important methods for exploring diagnostic strategies and predictive models for kidney transplant diseases. This study aims to explore the correlation between peripheral blood lymphocyte subpopulations and T cell-mediated rejection (TCMR) and antibody-mediated rejection (ABMR), as well as their diagnostic value, in conjunction with routine blood tests. METHODS: A total of 154 kidney transplant recipients, who met the inclusion and exclusion criteria and were treated at the Second Xiangya Hospital of Central South University from January to December, 2021, were selected as the study subjects. They were assigned into a stable group, a TCMR group, and an ABMR group, based on the occurrence and type of rejection. The basic and clinical data of these recipients were retrospectively analyzed and compared among the 3 groups. The transplant kidney function, routine blood tests, and peripheral blood lymphocyte subpopulation data of the TCMR group and the ABMR group before rejection treatment were compared with those of the stable group. RESULTS: The stable, TCMR group, and ABMR group showed no statistically significant differences in immunosuppressive maintenance regimens or sources of transplanted kidneys (all P>0.05). However, the post-transplant duration was significantly longer in the ABMR group compared with the stable group (P<0.001) and the TCMR group (P<0.05). Regarding kidney function, serum creatinine levels in the ABMR group were higher than in the stable group and the TCMR group (both P<0.01), with the TCMR group also showing higher levels than the stable group (P<0.01). Both TCMR and ABMR groups had significantly higher blood urea nitrogen levels than the stable group (P<0.01), with no statistically significant difference between TCMR and ABMR groups (P>0.05). The estimated glomerular filtration rate (eGFR) was lower in both TCMR and ABMR groups compared with the stable group (both P<0.01). In routine blood tests, the ABMR group had lower hemoglobin, red blood cell count, and platelet count than the stable group (all P<0.05). The TCMR group had higher neutrophil percentage (P<0.05) and count (P<0.05) than the stable group, and the ABMR group had a higher neutrophil percentage than the stable group (P<0.05). The eosinophil percentage and count in the TCMR group were lower than in the stable and ABMR groups (all P<0.05). Both TCMR and ABMR groups had lower basophil percentage and count, as well as lower lymphocyte percentage and count, compared with the stable group (all P<0.05). There were no significant differences in monocyte percentage and count among the 3 groups (all P>0.05). In lymphocyte subpopulations, the TCMR and ABMR groups had lower counts of CD45+ cells and T cells compared with the stable group (all P<0.05). The TCMR group also had lower counts of CD4+ T cells, NK cells, and B cells than the stable group (all P<0.05). There were no significant differences in the T cell percentage, CD4+ T cell percentage, CD8+ T cell percentage and their counts, CD4+/CD8+ T cell ratio, NK cell percentage, and B cell percentage among the stable, TCMR, and ABMR groups (all P>0.05). CONCLUSIONS: The occurrence of rejection leads to impaired transplant kidney function, accompanied by characteristic changes in some parameters of routine blood tests and peripheral blood lymphocyte subpopulations in kidney transplant recipients. The different characteristics of changes in some parameters of routine blood tests and peripheral blood lymphocyte subpopulations during TCMR and ABMR may help predict and diagnose rejection and differentiate between TCMR and ABMR.


Subject(s)
Graft Rejection , Kidney Transplantation , Humans , Graft Rejection/blood , Graft Rejection/diagnosis , Graft Rejection/immunology , Retrospective Studies , Female , Male , Lymphocyte Subsets/immunology , Adult , Middle Aged , T-Lymphocytes/immunology
6.
Nat Commun ; 15(1): 5953, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39009586

ABSTRACT

The intracellular bacterial pathogen Legionella pneumophila modulates host cell functions by secreting multiple effectors with diverse biochemical activities. In particular, effectors of the SidE family interfere with host protein ubiquitination in a process that involves production of phosphoribosyl ubiquitin (PR-Ub). Here, we show that effector LnaB converts PR-Ub into ADP-ribosylated ubiquitin, which is further processed to ADP-ribose and functional ubiquitin by the (ADP-ribosyl)hydrolase MavL, thus maintaining ubiquitin homeostasis in infected cells. Upon being activated by actin, LnaB also undergoes self-AMPylation on tyrosine residues. The activity of LnaB requires a motif consisting of Ser, His and Glu (SHxxxE) present in a large family of toxins from diverse bacterial pathogens. Thus, our study sheds light on the mechanisms by which a pathogen maintains ubiquitin homeostasis and identifies a family of enzymes capable of protein AMPylation.


Subject(s)
Bacterial Proteins , Homeostasis , Legionella pneumophila , Ubiquitin , Ubiquitination , Ubiquitin/metabolism , Legionella pneumophila/metabolism , Legionella pneumophila/pathogenicity , Humans , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , ADP-Ribosylation , Host-Pathogen Interactions , Adenosine Diphosphate Ribose/metabolism , Legionnaires' Disease/metabolism , Legionnaires' Disease/microbiology , HEK293 Cells , Actins/metabolism , HeLa Cells
7.
Heliyon ; 10(12): e32786, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-39022049

ABSTRACT

Background: Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac disease, and it has obvious genetic and clinical heterogeneity. Recently, heterozygous ALPK3 truncating variants (ALPK3tv) have been shown to cause HCM. However, the spectrum of ALPK3 variants and their relationships with the clinical characteristics of Chinese patients with HCM remain to be elucidated. Methods and results: Whole-exome sequencing data from 986 patients with HCM and 761 controls without HCM were utilized to analyze ALPK3 variants. Eleven ALPK3tv were detected in 18 patients with HCM (1.8 %), while no such variants were identified in controls. We also detected 21 rare ALPK3 missense variants in 16 patients with HCM (1.6 %) and 8 controls (1.1 %), respectively. ALPK3tv were significantly enriched in patients with HCM (P < 0.001), whereas the prevalence of missense variants was comparable between the HCM and control groups (P = 0.309). Patients with ALPK3tv exhibited a significantly lower left ventricular outflow tract gradient (P = 0.011) and a higher prevalence of apical HCM (27.8 %; P = 0.008). Conclusions: Our study supports that heterozygous ALPK3tv, but not APLK3 missense variants, are a genetic cause of HCM. Patients with HCM carrying ALPK3tv have a greater likelihood of developing apical HCM.

9.
Materials (Basel) ; 17(13)2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38998289

ABSTRACT

Polycarbonate (PC) as a widely used engineering plastic that shows disadvantages of flammability and large smoke production during combustion. Although many flame-retardant PCs have been developed, most of them show enhanced flame retardancy but poor smoke suppression or worsened mechanical performance. In this work, a novel nitrogen-phosphorus-sulfur synergistic flame retardant (Pc-FR) was synthesized and incorporated into PC with polytetrafluoroethylene (PTFE). The extremely low content of PC-FR (0.1-0.5 wt%) contributes significantly to the flame retardancy, smoke suppression and mechanical performance of PC. PC/0.3 wt% Pc-FR/0.3 wt% PTFE (PC-P0.3) shows the UL-94 V-0 and LOI of 33.5%. The PHRR, THR, PSPR, PCO and TCO of PC-P0.3 decreased by 39.44%, 14.38%, 17.45%, 54.75% and 30.61%, respectively. The impact strength and storage modulus of PC-P0.1 increased by 7.7 kJ/m2 and 26 MPa, respectively. The pyrolysis mechanism of PC-P0.3 is also revealed. The pyrolysis mechanism of PC-P0.3 is stochastic nucleation and subsequent growth and satisfies the Aevrami-Erofeev equation. The reaction order of PC-P0.3 is 1/2. The activation energy of PC-P0.3 is larger than PC-0, which proves that the Pc-FR can suppress the pyrolysis of the PC. This work offers a direction on how to design high-performance PC.

10.
Int J Biol Macromol ; 277(Pt 1): 134091, 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-39059543

ABSTRACT

This study introduces a novel 3D scaffold for bone regeneration, composed of silk fibroin, chitosan, nano-hydroxyapatite, LL-37 antimicrobial peptide, and pamidronate. The scaffold addresses a critical need in bone tissue engineering by simultaneously combating bone infections and promoting bone growth. LL-37 was incorporated for its broad-spectrum antimicrobial properties, while pamidronate was included to inhibit bone resorption. The scaffold's porous structure, essential for cell infiltration and nutrient diffusion, was achieved through a freeze-drying process. In vitro assessments using SEM and FTIR confirmed the scaffold's morphology and chemical integrity. Antimicrobial efficacy was tested against pathogens of Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa). In vivo studies in a murine model of infectious bone defect revealed the scaffold's effectiveness in reducing inflammation and bacterial load, and promoting bone regeneration. RNA sequencing of treated specimens provided insights into the molecular mechanisms underlying these observations, revealing significant gene expression changes related to bone healing and immune response modulation. The results indicate that the scaffold effectively inhibits bacterial growth and supports bone cell functions, making it a promising candidate for treating infectious bone defects. Future studies should focus on optimizing the release of therapeutic agents and evaluating the scaffold's clinical potential.

11.
J Am Chem Soc ; 146(31): 21453-21465, 2024 Aug 07.
Article in English | MEDLINE | ID: mdl-39052434

ABSTRACT

As the most promising hydrogen evolution reaction (HER) electrocatalysts, platinum (Pt)-based catalysts still struggle with sluggish kinetics and expensive costs in alkaline media. Herein, we accelerate the alkaline hydrogen evolution kinetics by optimizing the local environment of Pt species and metal oxide heterointerfaces. The well-dispersed PtRu bimetallic clusters with adjacent MO2-x (M = Sn and Ce) on carbon nanotubes (PtRu/CNT@MO2-x) are demonstrated to be a potential electrocatalyst for alkaline HER, exhibiting an overpotential of only 75 mV at 100 mA cm-2 in 1 M KOH. The excellent mass activity of 12.3 mA µg-1Pt+Ru and specific activity of 32.0 mA cm-2ECSA at an overpotential of 70 mV are 56 and 64 times higher than those of commercial Pt/C. Experimental and theoretical investigations reveal that the heterointerfaces between Pt clusters and MO2-x can simultaneously promote H2O adsorption and activation, while the modification with Ru further optimizes H adsorption and H2O dissociation energy barriers. Then, the matching kinetics between the accelerated elementary steps achieved superb hydrogen generation in alkaline media. This work provides new insight into catalytic local environment design to simultaneously optimize the elementary steps for obtaining ideal alkaline HER performance.

12.
Sci Rep ; 14(1): 17761, 2024 08 01.
Article in English | MEDLINE | ID: mdl-39085575

ABSTRACT

This retrospective study analyzed a large population of gastric cancer (GC) patients treated between 2010 and 2015 to investigate the clinical features and predictive risk factors for developing secondary primary malignancies (SPMs). The cumulative incidence of SPM was assessed using Kaplan-Meier analysis. Competing risk analyses adjusted for mortality were conducted using stratified Cox proportional hazard regression models and multivariate analyses to identify independent predictors of SPM. A total of 3289 out of 167,747 GC patients were included in the analytic cohort, with 155 patients diagnosed with SPM. Patients whose histologic type other than adenocarcinomas (AC) and signet ring cell carcinoma (SRCC) emerged as an independent risk factor for developing SPM (hazard ratio [HR] 2.262, 95% confidence interval [CI] 1.146-4.465, P = 0.019) in multivariate Cox regression analysis. The surgical method, including biopsy/local excision (HR 2.3, [CI] 1.291-4.095, P = 0.005) and subtotal/total resection ([HR] 1.947, [CI] 1.028-3.687, P = 0.041), chemotherapy ([HR] 1.527, [CI] 1.006-2.316, P = 0.047), and histologic type ([HR] 2.318, [CI] 1.193-4.504, P = 0.013)), were identified as independent risk factors in the competitive risk model. Subgroup analyses, stratified by chemotherapy, revealed an increased risk of SPM among older patients. Furthermore, a nomogram was developed and internally validated to predict the cumulative incidence of SPM in GC patients (C-index = 0.73 for 72 months). These findings suggested that in specific histologic types of GC, the lymph node infiltration region missed after local surgical resection, and concomitant chemotherapy would have an increased risk of SPM for cancer survivors.


Subject(s)
Neoplasms, Second Primary , SEER Program , Stomach Neoplasms , Humans , Stomach Neoplasms/epidemiology , Stomach Neoplasms/pathology , Male , Female , Neoplasms, Second Primary/epidemiology , Neoplasms, Second Primary/pathology , Risk Factors , Middle Aged , Aged , Retrospective Studies , Incidence , Adult , Kaplan-Meier Estimate , Proportional Hazards Models
13.
Sci Data ; 11(1): 773, 2024 Jul 13.
Article in English | MEDLINE | ID: mdl-39003335

ABSTRACT

Runoff and evapotranspiration (ET) are pivotal constituents of the water, energy, and carbon cycles. This research presents a 5-km monthly gridded runoff and ET dataset for 1998-2017, encompassing seven headwaters of Tibetan Plateau rivers (Yellow, Yangtze, Mekong, Salween, Brahmaputra, Ganges, and Indus) (hereinafter TPRED). The dataset was generated using the advanced cryosphere-hydrology model WEB-DHM, yielding a Nash coefficient ranging from 0.77 to 0.93 when compared to the observed discharges. The findings indicate that TPRED's monthly runoff notably outperforms existing datasets in capturing hydrological patterns, as evidenced by robust metrics such as the correlation coefficient (CC) (0.944-0.995), Bias (-0.68-0.53), and Root Mean Square Error (5.50-15.59 mm). Additionally, TPRED's monthly ET estimates closely align with expected seasonal fluctuations, as reflected by a CC ranging from 0.94 to 0.98 when contrasted with alternative ET products. Furthermore, TPRED's annual values exhibit commendable concordance with operational products across multiple dimensions. Ultimately, the TPRED will have great application on hydrometeorology, carbon transport, water management, hydrological modeling, and sustainable development of water resources.

14.
J Orthop Surg Res ; 19(1): 440, 2024 Jul 27.
Article in English | MEDLINE | ID: mdl-39068450

ABSTRACT

OBJECTIVE: The aim of this study is to evaluate the clinical efficacy of injectable cemented hollow pedicle screw (CICPS) in the treatment of osteoporotic lumbar degenerative diseases through a large sample long-term follow-up study. Additionally, we aim to explore the risk factors affecting interbody fusion. METHODS: A total of 98 patients who underwent CICPS for transforaminal lumbar interbody fusion (TLIF) for osteoporotic lumbar degenerative disease from March 2011 to September 2017 were analyzed. X-ray and electronic computed tomography (CT) imaging data were collected during preoperative, postoperative, and follow-up periods. The data included changes in intervertebral space height (ΔH), screw failure, cement leakage (CL), and intervertebral fusion. The patients were divided into two groups based on their fusion status one year after surgery: satisfied group A and dissatisfied group B. Surgical data such as operation time, intraoperative bleeding volume and surgical complications were recorded, and visual analog scale (VAS) and Oswestry disability index (ODI) were used to evaluate the improvement of lumbar and leg pain. RESULTS: The mean follow-up time was 101.29 months (ranging from 70 to 128 months). A total of 320 CICPS were used, with 26 screws (8.13%) leaking, 3 screws (0.94%) experiencing cement augmentation failure, and 1 screw (0.31%) becoming loose and breaking. The remaining screws were not loose or pulled out. Female gender, decreased bone density, and CL were identified as risk factors affecting interbody fusion (P < 0.05). Early realization of interbody fusion can effectively prevent the loss of intervertebral space height (P < 0.05) and maintain the surgical treatment effect. Both VAS and ODI scores showed significant improvement during the follow-up period (P < 0.05). Binary logistic regression analysis revealed that decreased bone density and cement leakage were risk factors for prolonged interbody fusion. CONCLUSIONS: The results of long-term follow-up indicate that PMMA enhanced CICPS has unique advantages in achieving good clinical efficacy in the treatment of osteoporosis lumbar degenerative diseases. Attention should be paid to identify female gender, severe osteoporosis, and CL as risk factors affecting interbody fusion.


Subject(s)
Bone Cements , Lumbar Vertebrae , Osteoporosis , Pedicle Screws , Spinal Fusion , Humans , Female , Male , Lumbar Vertebrae/surgery , Lumbar Vertebrae/diagnostic imaging , Follow-Up Studies , Aged , Osteoporosis/surgery , Osteoporosis/complications , Middle Aged , Spinal Fusion/methods , Spinal Fusion/instrumentation , Intervertebral Disc Degeneration/surgery , Intervertebral Disc Degeneration/diagnostic imaging , Treatment Outcome , Time Factors , Injections , Retrospective Studies
15.
Circ J ; 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38839351

ABSTRACT

BACKGROUND: Studies on the relationship between the preoperative quantitative flow ratio (QFR) and parameters of intraoperative transit time flow measurement (TTFM) are extremely rare. In addition, the predictive value of QFR and TTFM parameters for early internal mammary artery (IMA) failure after coronary artery bypass grafting still needs to be validated.Methods and Results: We retrospectively collected data from 510 patients who underwent in situ IMA grafting to the left anterior descending (LAD) artery at Fuwai Hospital. Spearman correlation coefficients between preoperative QFR of the LAD artery and intraoperative TTFM parameters of the IMA were -0.13 (P=0.004) for mean graft flow (Qm) and 0.14 (P=0.002) for the pulsatility index (PI). QFR and TTFM exhibited similar and good predictive value for early IMA failure (5.7% at 1 year), and they were better than percentage diameter stenosis (area under the curve 0.749 for QFR, 0.733 for Qm, 0.688 for PI, and 0.524 for percentage diameter stenosis). The optimal cut-off value of QFR was 0.765. Both univariate and multivariable regression analyses revealed that QFR >0.765, Qm ≤15 mL/min, and PI >3.0 independently contributed to early IMA failure. CONCLUSIONS: There were statistically significant correlations between preoperative QFR of the LAD artery and intraoperative TTFM parameters (Qm, PI) of the IMA. Preoperative QFR and intraoperative Qm and PI exhibited excellent predictive value for early IMA failure.

16.
Accid Anal Prev ; 204: 107620, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38823082

ABSTRACT

As autonomous driving advances, autonomous vehicles will share the road with human drivers. This requires autonomous vehicles to adhere to human traffic laws under safe conditions. Simultaneously, when confronted with dangerous situations, autonomous driving should also possess the capability to deviate from traffic laws to ensure safety. However, current autonomous vehicles primarily prioritize safety and collision avoidance in their decision-making and planning. This may lead to misunderstandings and distrust from human drivers in mixed traffic flow, and even accidents. To address this, this paper proposes a decoupled hierarchical framework for compliance safety decision-making. The framework primarily consists of two layers: the decision-making layer and the motion planning layer. In the decision-making layer, a candidate behavior set is constructed based on the scenario, and a dual layer admission assessment is utilized to filter out unsafe and non-compliant behaviors from the candidate sets. Subsequently, the optimal behavior is selected as the decision behavior according to the designed evaluation metrics. The decision-making layer ensures that the vehicle can meet lane safety requirements and comply with static traffic laws. In the motion planning layer, the surrounding vehicles and the road are modeled as safety potential fields and traffic laws potential fields. Combining the optimal decision behavior, they are incorporated into the cost function of the model predictive control to achieve compliant and safe trajectory planning. The planning layer ensures that the vehicle meets trajectory safety requirements and complies with dynamic traffic laws under safe conditions. Finally, four typical scenarios are used to evaluate the effectiveness of the proposed method. The results indicate that the proposed method can ensure compliance in safe conditions while also temporarily deviating from traffic laws in emergency situations to ensure safety.


Subject(s)
Accidents, Traffic , Automobile Driving , Decision Making , Safety , Humans , Automobile Driving/legislation & jurisprudence , Accidents, Traffic/prevention & control , Accidents, Traffic/legislation & jurisprudence , Safety/legislation & jurisprudence , Automation , Automobiles/legislation & jurisprudence , Models, Theoretical
17.
Glob Chang Biol ; 30(6): e17357, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38822559

ABSTRACT

Determination of tipping points in nitrogen (N) isotope (δ15N) natural abundance, especially soil δ15N, with increasing aridity, is critical for estimating N-cycling dynamics and N limitation in terrestrial ecosystems. However, whether there are linear or nonlinear responses of soil δ15N to increases in aridity and if these responses correspond well with soil N cycling remains largely unknown. In this study, we investigated soil δ15N and soil N-cycling characteristics in both topsoil and subsoil layers along a drought gradient across a 3000-km transect of drylands on the Qinghai-Tibetan Plateau. We found that the effect of increasing aridity on soil δ15N values shifted from negative to positive with thresholds at aridity index (AI) = 0.27 and 0.29 for the topsoil and subsoil, respectively, although soil N pools and N transformation rates linearly decreased with increasing aridity in both soil layers. Furthermore, we identified markedly different correlations between soil δ15N and soil N-cycling traits above and below the AI thresholds (0.27 and 0.29 for topsoil and subsoil, respectively). Specifically, in wetter regions, soil δ15N positively correlated with most soil N-cycling traits, suggesting that high soil δ15N may result from the "openness" of soil N cycling. Conversely, in drier regions, soil δ15N showed insignificant relationships with soil N-cycling traits and correlated well with factors, such as soil-available phosphorus and foliage δ15N, demonstrating that pathways other than typical soil N cycling may dominate soil δ15N under drier conditions. Overall, these results highlight that different ecosystem N-cycling processes may drive soil δ15N along the aridity gradient, broadening our understanding of N cycling as indicated by soil δ15N under changing drought regimes. The aridity threshold of soil δ15N should be considered in terrestrial N-cycling models when incorporating 15N isotope signals to predict N cycling and availability under climatic dryness.


Subject(s)
Droughts , Ecosystem , Nitrogen Cycle , Nitrogen Isotopes , Soil , Soil/chemistry , Nitrogen Isotopes/analysis , China , Nitrogen/analysis , Nitrogen/metabolism , Desert Climate
18.
Article in English | MEDLINE | ID: mdl-38936810

ABSTRACT

AIM: To investigate the DNA damage response (DDR) in a cyclophosphamide (CTX)-induced mouse model of premature ovarian failure (POF). METHODS: The POF model was established by injecting mice with CTX. The body, ovarian weights, the estrus cycle, and pathological changes of the ovaries were recorded. The serum levels of 17 ß-estradiol (E2) and follicle-stimulating hormone (FSH) were measured. The expression of Ki67, ß-galactosidase (ß-gal), p21, p53, γH2AX, and pATM in ovarian tissues was detected by immunohistochemistry. The expression of ß-gal, γH2AX, and pATM was analyzed by immunofluorescence staining of primary cultured granulosa cells (GCs). RESULTS: The body and ovarian weights decreased, the estrus cycles were erratic, and the FSH level increased, whereas the E2 level decreased in POF mice compared to controls. The pathological consequences of POF revealed an increase in atretic follicles, corpus luteum, and primordial follicles and a decrease in the number of primary, secondary, and tertiary follicles. Ki67 expression was reduced, ß-gal, p21, p53, γH2AX, and pATM expression were elevated in the ovaries of POF mice. The expression of ß-gal, γH2AX, and pATM increased in GCs with the concentration in a time-dependent manner. CONCLUSION: In total, CTX induced POF in mice, which was mediated by the DDR pathway of ATM-P53-P21.

19.
Nature ; 631(8019): 134-141, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38867047

ABSTRACT

Mosaic loss of the X chromosome (mLOX) is the most common clonal somatic alteration in leukocytes of female individuals1,2, but little is known about its genetic determinants or phenotypic consequences. Here, to address this, we used data from 883,574 female participants across 8 biobanks; 12% of participants exhibited detectable mLOX in approximately 2% of leukocytes. Female participants with mLOX had an increased risk of myeloid and lymphoid leukaemias. Genetic analyses identified 56 common variants associated with mLOX, implicating genes with roles in chromosomal missegregation, cancer predisposition and autoimmune diseases. Exome-sequence analyses identified rare missense variants in FBXO10 that confer a twofold increased risk of mLOX. Only a small fraction of associations was shared with mosaic Y chromosome loss, suggesting that distinct biological processes drive formation and clonal expansion of sex chromosome missegregation. Allelic shift analyses identified X chromosome alleles that are preferentially retained in mLOX, demonstrating variation at many loci under cellular selection. A polygenic score including 44 allelic shift loci correctly inferred the retained X chromosomes in 80.7% of mLOX cases in the top decile. Our results support a model in which germline variants predispose female individuals to acquiring mLOX, with the allelic content of the X chromosome possibly shaping the magnitude of clonal expansion.


Subject(s)
Aneuploidy , Chromosomes, Human, X , Clone Cells , Leukocytes , Mosaicism , Adult , Female , Humans , Male , Middle Aged , Alleles , Autoimmune Diseases/genetics , Biological Specimen Banks , Chromosome Segregation/genetics , Chromosomes, Human, X/genetics , Chromosomes, Human, Y/genetics , Clone Cells/metabolism , Clone Cells/pathology , Exome/genetics , F-Box Proteins/genetics , Genetic Predisposition to Disease/genetics , Germ-Line Mutation , Leukemia/genetics , Leukocytes/metabolism , Models, Genetic , Multifactorial Inheritance/genetics , Mutation, Missense/genetics
20.
Small ; : e2404470, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38934337

ABSTRACT

The uncontrollable growth of lithium dendrites and the flammability of electrolytes are the direct impediments to the commercial application of high-energy-density lithium metal batteries (LMBs). Herein, this study presents a novel approach that combines microencapsulation and electrospinning technologies to develop a multifunctional composite separator (P@AS) for improving the electrochemical performance and safety performance of LMBs. The P@AS separator forms a dense charcoal layer through the condensed-phase flame retardant mechanism causing the internal separator to suffocate from lack of oxygen. Furthermore, it incorporates a triple strategy promoting the uniform flow of lithium ions, facilitating the formation of a highly ion-conducting solid electrolyte interface (SEI), and encouraging flattened lithium deposition with active SiO2 seed points, considerably suppressing lithium dendrites growth. The high Coulombic efficiency of 95.27% is achieved in Li-Cu cells with additive-free carbonate electrolyte. Additionally, stable cycling performance is also maintained with a capacity retention rate of 93.56% after 300 cycles in LFP//Li cells. Importantly, utilizing P@AS separator delays the ignition of pouch batteries under continuous external heating by 138 s, causing a remarkable reduction in peak heat release rate and total heat release by 23.85% and 27.61%, respectively, substantially improving the fire safety of LMBs.

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