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Pressure injuries (PIs) are a common healthcare problem worldwide and are considered to be the most expensive chronic wounds after arterial ulcers. Although the gross factors including ischemia-reperfusion (I/R) have been identified in the etiology of PIs, the precise cellular and molecular mechanisms contributing to PIs development remain unclear. Various forms of programmed cell death including apoptosis, autophagy, pyroptosis, necroptosis and ferroptosis have been identified in PIs. In this paper, we present a detailed overview on various forms of cell death; discuss the recent advances in the roles of cell death in the occurrence and development of PIs and found much of the evidence is novel and based on animal experiments. Herein, we also state critical evaluation of the existing data and future perspective in the field. A better understanding of the programmed cell death mechanism in PIs may have important implications in driving the development of new preventive and therapeutic strategies.
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Ancient Chinese is a crucial bridge for understanding Chinese history and culture. Most existing works utilize high-resource modern Chinese to understand low-resource ancient Chinese, but they fail to fully consider the semantic and syntactic gaps between them due to their changes over time, resulting in the misunderstanding of ancient Chinese. Hence, we propose a novel language pre-training framework for ancient Chinese understanding based on the Cross-temporal Contrastive Disentanglement Model (CCDM), which bridges the gap between modern and ancient Chinese with their parallel corpus. Specifically, we first explore a cross-temporal data augmentation method by disentangling and reconstructing the parallel ancient-modern corpus. It is noteworthy that the proposed decoupling strategy takes full account of the cross-temporal character between ancient and modern Chinese. Then, cross-temporal contrastive learning is exploited to train the model by fully leveraging the cross-temporal information. Finally, the trained language model is utilized for downstream tasks. We conduct extensive experiments on six ancient Chinese understanding tasks. Results demonstrate that our model outperforms the state-of-the-art baselines. Our framework also holds potential applicability to other languages that have undergone evolutionary changes, leading to shifts in syntax and semantics.1.
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Purpose: This study aims to identify the key factors influencing health-related quality of life (HRQoL) of pediatric acute myeloid leukemia (AML) patients following their initial diagnosis and examine their impact on the five-year survival prognosis. Methods: A chart review and follow-up were conducted for children with AML who participated in a prospective cohort study between 2017 and 2020. We identified factors influencing HRQoL through Pediatric Quality of Life Inventory™ (PedsQL™ 4.0), PedsQL™ Cancer Module 3.0 (CM 3.0) and PedsQL™ Family Impact Module 2.0 (FIM 2.0), as well as assessed the impact of impaired HRQoL on the overall outcomes of patients. Results: Sixty-four subjects enrolled in the study had complete HRQoL outcome data, and 61 of them completed the 5-year follow-up. In CM 3.0, age was positively associated with parental proxy reports (p = 0.040), whereas divorced families were negatively associated with child self-reports (p = 0.045). A positive medical history correlates with FIM 2.0 (p = 0.025). Residence (p = 0.046), the occupation of caregivers (p = 0.014), disease severity (p = 0.024), and the only child (p = 0.029) exhibited statistically significant associations with the impairment of HRQoL. Impaired HRQoL scores shown by the PedsQL™4.0 parent proxy report (p = 0.013) and FIM 2.0 (p = 0.011) were associated with a reduced 5-year survival rate. Conclusions: This study demonstrated that early impairment of HRQoL in pediatric acute myeloid leukemia patients has predictive value for long-term prognosis. Once validated, these findings may provide some guidance to clinicians treating children with AML.
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p-Benzoquinones are important organic intermediates in the synthesis of biopharmaceuticals and fine chemicals. In this study, two crystalline 3D polyoxovanadate-based metal-organic frameworks, H[Cu(tpi)2]{Cu2V7O21}·H2O (1, tpi = C18N5H13) and [Co(Htpi)2]{V4O12} (2, Htpi = C18N5H14), were synthesized, which as heterogeneous catalysts showed excellent catalytic activities for the synthesis of p-benzoquinones. Both compounds were characterized by IR, UV-vis diffuse reflectance spectroscopy, TG, XPS, X-ray diffraction, etc. In 1, {Cu2V7} clusters are connected together by copper cations and 1D Cu-organic coordination chains to yield a 3D polyoxometalate-based metal-organic framework (POMOF); in 2, adjacent 2D bimetallic oxide layers, constructed from 1D polyoxovanadate chains and cobalt ions, are further connected by 1D Co-organic coordination chains to form a 3D POMOF. Noteworthily, in the synthesis of trimethyl-p-benzoquinone, the key intermediate of vitamin E, using 2,3,6-trimethylphenol as the model substrate, the turnover frequency values for compounds 1 and 2 can, respectively, reach 607 and 380 h-1 in 8 min. Furthermore, both compounds demonstrated excellent recyclability and structural stability, characterized by PXRD and IR. The catalytic mechanism reveals that both the homolytic radical mechanism and heterolytic oxygen atom transfer mechanism are involved.
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Intestinal ischemia/reperfusion is a prevalent pathological process that can result in intestinal dysfunction, bacterial translocation, energy metabolism disturbances, and subsequent harm to distal tissues and organs via the circulatory system. Acute lung injury frequently arises as a complication of intestinal ischemia/reperfusion, exhibiting early onset and a grim prognosis. Without appropriate preventative measures and efficacious interventions, this condition may progress to acute respiratory distress syndrome and elevate mortality rates. Nonetheless, the precise mechanisms and efficacious treatments remain elusive. This paper synthesizes recent research models and pertinent injury evaluation criteria within the realm of acute lung injury induced by intestinal ischemia/reperfusion. The objective is to investigate the roles of pathophysiological mechanisms like oxidative stress, inflammatory response, apoptosis, ferroptosis, and pyroptosis; and to assess the strengths and limitations of current therapeutic approaches for acute lung injury stemming from intestinal ischemia/reperfusion. The goal is to elucidate potential targets for enhancing recovery rates, identify suitable treatment modalities, and offer insights for translating fundamental research into clinical applications.
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Owing to their lack of outer skin, Chinese bayberries are highly susceptible to mechanical damage during picking, which accelerates bacterial invasion and rotting, shortening their shelf life. In this study, montmorillonite (MMT) was used to absorb an aqueous sodium chlorite solution embedded in a carboxymethyl cellulose sodium hydrogel after freeze drying, and the hydrogel was crosslinked by Al3+ ions. Al3+ hydrolyzed to produce H+, creating an acidic environment within the hydrogel and reacting with NaClO2 to slowly release ClO2. We prepared a ClO2 slow-release hydrogel gasket with 0.5 wt% MMT-NaClO2 and investigated its storage effect on postharvest Chinese bayberries. Its inhibition rates against Escherichia coli and Listeria monocytogenes were 98.84% and 98.96%, respectively. The results showed that the gasket preserved the appearance and nutritional properties of the berries. The antibacterial hydrogel reduced hardness loss by 26.57% and ascorbic acid loss by 46.36%. This new storage method could also be applicable to other fruits and vegetables.
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Antibacterianos , Bentonita , Carboximetilcelulose Sódica , Escherichia coli , Conservação de Alimentos , Frutas , Hidrogéis , Antibacterianos/farmacologia , Antibacterianos/química , Bentonita/química , Bentonita/farmacologia , Carboximetilcelulose Sódica/química , Carboximetilcelulose Sódica/farmacologia , Escherichia coli/efeitos dos fármacos , Conservação de Alimentos/métodos , Conservação de Alimentos/instrumentação , Frutas/química , Frutas/microbiologia , Hidrogéis/química , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Myrica/químicaRESUMO
Traditional atmospheric chemistry posits that sulfur dioxide (SO2) can be oxidized to sulfate (SO42-) through aqueous-phase reactions in clouds and gas-phase oxidation. Despite adequate knowledge of traditional mechanisms, several studies have highlighted the potential for SO2 oxidation within aerosol water. Given the widespread presence of tropospheric aerosols, SO42- production through aqueous-phase oxidation in aerosol water could have a pervasive global impact. Here, we quantify the potential contributions of aerosol aqueous pathways to global sulfate formation based on the GEOS-Chem simulations and subsequent theoretical calculations. Hydrogen peroxide (H2O2) oxidation significantly influences continental regions both horizontally and vertically. Over the past two decades, shifts in the formation pathways within typical cities reveal an intriguing trend: despite reductions in SO2 emissions, the increased atmospheric oxidation capacities, like rising H2O2 levels, prevent a steady decline in SO42- concentrations. Abating oxidants would facilitate the benefit of SO2 reduction and the positive feedback in sulfate mitigation.
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Immune-checkpoint blockade (ICB) reinvigorates T cells from exhaustion and potentiates T-cell responses to tumors. However, most patients do not respond to ICB therapy, and only a limited response can be achieved in a "cold" tumor with few infiltrated lymphocytes. Synthetic biology can be used to engineer bacteria as controllable bioreactors to synthesize biotherapeutics in situ. We engineered attenuated Salmonella VNP20009 with synthetic gene circuits to produce PD-1 and Tim-3 scFv to block immunosuppressive receptors on exhausted T cells to reinvigorate their antitumor response. Secreted PD-1 and Tim-3 scFv bound PD-1+ Tim-3+ T cells through their targeting receptors in vitro and potentiated the T-cell secretion of IFN-γ. Engineered bacteria colonized the hypoxic core of the tumor and synthesized PD-1 and Tim-3 scFv in situ, reviving CD4+ T cells and CD8+ T cells to execute an antitumor response. The bacteria also triggered a strong innate immune response, which stimulated the expansion of IFN-γ+ CD4+ T cells within the tumors to induce direct and indirect antitumor immunity.
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Inibidores de Checkpoint Imunológico , Receptor de Morte Celular Programada 1 , Salmonella , Inibidores de Checkpoint Imunológico/farmacologia , Animais , Receptor de Morte Celular Programada 1/metabolismo , Receptor de Morte Celular Programada 1/imunologia , Camundongos , Salmonella/imunologia , Salmonella/genética , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Receptor Celular 2 do Vírus da Hepatite A/genética , Linhagem Celular Tumoral , Linfócitos T CD8-Positivos/imunologia , Humanos , Interferon gama/metabolismo , Interferon gama/imunologia , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/farmacologia , Camundongos Endogâmicos C57BL , Biologia Sintética/métodos , Linfócitos T CD4-Positivos/imunologia , Imunoterapia/métodosRESUMO
BACKGROUND: Diabetes mellitus (DM) can aggravate lung ischemia-reperfusion (I/R) injury and is a significant risk factor for recipient mortality after lung transplantation. Metformin protects against I/R injury in a variety of organs. However, the effect of metformin on diabetic lung I/R injury remains unclear. Therefore, this study aimed to observe the effect and mechanism of metformin on lung I/R injury following lung transplantation in type 2 diabetic rats. METHODS: Sprague-Dawley rats were randomly divided into the following six groups: the control + sham group (CS group), the control + I/R group (CIR group), the DM + sham group (DS group), the DM + I/R group (DIR group), the DM + I/R + metformin group (DIRM group) and the DM + I/R + metformin + Compound C group (DIRMC group). Control and diabetic rats underwent the sham operation or left lung transplantation operation. Lung function, alveolar capillary permeability, inflammatory response, oxidative stress, necroptosis and the p-AMPK/AMPK ratio were determined after 24 h of reperfusion. RESULTS: Compared with the CIR group, the DIR group exhibited decreased lung function, increased alveolar capillary permeability, inflammatory responses, oxidative stress and necroptosis, but decreased the p-AMPK/AMPK ratio. Metformin improved the function of lung grafts, decreased alveolar capillary permeability, inflammatory responses, oxidative stress and necroptosis, and increased the p-AMPK/AMPK ratio. In contrast, the protective effects of metformin were abrogated by Compound C. CONCLUSIONS: Metformin attenuates lung I/R injury and necroptosis through AMPK pathway in type 2 diabetic lung transplant recipient rats.
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Proteínas Quinases Ativadas por AMP , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Transplante de Pulmão , Metformina , Necroptose , Traumatismo por Reperfusão , Animais , Ratos , Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Hipoglicemiantes/farmacologia , Pulmão/patologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Lesão Pulmonar/prevenção & controle , Lesão Pulmonar/etiologia , Lesão Pulmonar/metabolismo , Metformina/farmacologia , Necroptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle , Transdução de Sinais/efeitos dos fármacosRESUMO
Zinc (Zn) is a vital micronutrient that strengthens the immune system, aids cellular activities, and treats infectious diseases. A deficiency in Zn can lead to an imbalance in the immune system. This imbalance is particularly evident in severe deficiency cases, where there is a high susceptibility to various viral infections, including COVID-19 caused by SARS-CoV-2. This review article examines the nutritional roles of Zn in human health, the maintenance of Zn concentration, and Zn uptake. As Zn is an essential trace element that plays a critical role in the immune system and is necessary for immune cell function and cell signaling, the roles of Zn in the human immune system, immune cells, interleukins, and its role in SARS-CoV-2 infection are further discussed. In summary, this review paper encapsulates the nutritional role of Zn in the human immune system, with the hope of providing specific insights into Zn research.
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BACKGROUND: This study aimed to elucidate the prognostic role of Masked Morning Hypertension (MMH) in non-dialysis-dependent chronic kidney disease (NDD-CKD). METHODS: 2,130 NDD-CKD patients of the inpatient department were categorized into four blood pressure (BP) groups: clinical normotension (CH-), clinical hypertension (CH+) with morning hypertension (MH+), and without MH+ (MH-) respectively. The correlation between these four BP types and the primary (all-cause mortality) and secondary endpoints (cardio-cerebrovascular disease [CVD] and end-stage kidney disease [ESKD]) was analyzed. RESULTS: The prevalence of MH and MMH were 47.4% and 14.98%, respectively. Morning hypertension independently increased the risk of all-cause mortality (Pâ =â 0.004) and CVD (Pâ <â 0.001) but not ESKD (Pâ =â 0.092). Masked morning hypertension was associated with heightened all-cause mortality (HRâ =â 4.22, 95% CIâ =â 1.31-13.59; Pâ =â 0.02) and CVD events (HRâ =â 5.14, 95% CIâ =â 1.37-19.23; Pâ =â 0.02), with no significant association with ESKD (HRâ =â 1.18, 95% CIâ =â 0.65-2.15; Pâ =â 0.60). When considering non-CVD deaths as a competing risk factor, a high cumulative incidence of CVD events was observed in the MMH group (HRâ =â 5.16, 95% CIâ =â 1.39-19.08). CONCLUSIONS: MMH is an independent risk factor for all-cause mortality and combined cardiovascular and cerebrovascular events in NDD-CKD patients, underscoring its prognostic significance. This highlights the need for comprehensive management of MH in this population.
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Pressão Sanguínea , Insuficiência Renal Crônica , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/mortalidade , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/complicações , Idoso , Prognóstico , China/epidemiologia , Prevalência , Fatores de Risco , Ritmo Circadiano , Hipertensão Mascarada/epidemiologia , Hipertensão Mascarada/diagnóstico , Hipertensão Mascarada/fisiopatologia , Pacientes Internados , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/fisiopatologia , Falência Renal Crônica/mortalidade , Fatores de Tempo , Medição de Risco , Causas de Morte , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/mortalidade , População do Leste AsiáticoRESUMO
IRAK1 has been implicated in promoting development of various types of cancers and mediating radioresistance. However, its role in cervical cancer tumorigenesis and radioresistance, as well as the potential underlying mechanisms, remain poorly defined. In this study, we evaluated IRAK1 expression in radiotherapy-treated cervical cancer tissues and found that IRAK1 expression is negatively associated with the efficacy of radiotherapy. Consistently, ionizing radiation (IR)-treated HeLa and SiHa cervical cancer cells express a lower level of IRAK1 than control cells. Depletion of IRAK1 resulted in reduced activation of the NF-κB pathway, decreased cell viability, downregulated colony formation efficiency, cell cycle arrest, increased apoptosis, and impaired migration and invasion in IR-treated cervical cancer cells. Conversely, overexpressing IRAK1 mitigated the anti-cancer effects of IR in cervical cancer cells. Notably, treatment of IRAK1-overexpressing IR-treated HeLa and SiHa cells with the NF-κB pathway inhibitor pyrrolidine dithiocarbamate (PDTC) partially counteracted the effects of excessive IRAK1. Furthermore, our study demonstrated that IRAK1 deficiency enhanced the anti-proliferative role of IR treatment in a xenograft mouse model. These collective observations highlight IRAK1's role in mitigating the anti-cancer effects of radiotherapy, partly through the activation of the NF-κB pathway. SUMMARY: IRAK1 enhances cervical cancer resistance to radiotherapy, with IR treatment reducing IRAK1 expression and increasing cancer cell vulnerability and apoptosis.
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Apoptose , Quinases Associadas a Receptores de Interleucina-1 , NF-kappa B , Neoplasias do Colo do Útero , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Humanos , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Feminino , Animais , NF-kappa B/metabolismo , Apoptose/efeitos da radiação , Camundongos , Células HeLa , Proliferação de Células , Camundongos Nus , Linhagem Celular Tumoral , Transdução de Sinais , Movimento Celular , Tolerância a Radiação , Ensaios Antitumorais Modelo de Xenoenxerto , Sobrevivência Celular/efeitos da radiação , Radiação IonizanteRESUMO
INTRODUCTION: There are emerging but inconsistent evidences about anti-epileptic drugs (AEDs) as radio- or chemo-sensitizers to improve survival in glioblastoma patients. We conducted a nationwide population-based study to evaluate the impact of concurrent AED during post-operative chemo-radiotherapy on outcome. MATERIAL AND METHODS: A total of 1057 glioblastoma patients were identified by National Health Insurance Research Database and Cancer Registry in 2008-2015. Eligible criteria included those receiving surgery, adjuvant radiotherapy and temozolomide, and without other cancer diagnoses. Survival between patients taking concurrent AED for 14 days or more during chemo-radiotherapy (AED group) and those who did not (non-AED group) were compared, and subgroup analyses for those with valproic acid (VPA), levetiracetam (LEV), or phenytoin were performed. Multivariate analyses were used to adjust for confounding factors. RESULTS: There were 642 patients in the AED group, whereas 415 in the non-AED group. The demographic data was balanced except trend of more patients in the AED group had previous drug history of AEDs (22.6% vs. 18%, P 0.078). Overall, the AED group had significantly increased risk of mortality (HR = 1.18, P 0.016) compared to the non-AED group. Besides, an adverse dose-dependent relationship on survival was also demonstrated in the AED group (HR = 1.118, P 0.0003). In subgroup analyses, the significant detrimental effect was demonstrated in VPA group (HR = 1.29,P 0.0002), but not in LEV (HR = 1.18, P 0.079) and phenytoin (HR = 0.98, P 0.862). CONCLUSIONS: Improved survival was not observed in patients with concurrent AEDs during chemo-radiotherapy. Our real-world data did not support prophylactic use of AEDs for glioblastoma patients.
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Anticonvulsivantes , Neoplasias Encefálicas , Glioblastoma , Humanos , Feminino , Anticonvulsivantes/uso terapêutico , Masculino , Glioblastoma/mortalidade , Glioblastoma/terapia , Pessoa de Meia-Idade , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Idoso , Quimiorradioterapia Adjuvante/métodos , Quimiorradioterapia Adjuvante/estatística & dados numéricos , Adulto , Estudos de Coortes , Fenitoína/uso terapêutico , Fenitoína/administração & dosagem , Sistema de Registros/estatística & dados numéricos , Levetiracetam/uso terapêutico , Ácido Valproico/uso terapêuticoRESUMO
BACKGROUND: Pressure injuries (PIs) are one of the leading potentially preventable hospital-acquired complications associated with prolonged hospital length, poor quality of life and financial burden. The relationship between body mass index (BMI) and PIs occurrence is controversial. OBJECTIVE: The aim of this study was to further examine relationships between BMI and PIs occurrence in hospitalized patients. DESIGN: A multi-center prospective study. SETTING: 39 hospitals located in northwest China from April 2021 to July 2023. PARTICIPANTS: 175,960 hospitalized patients aged over 18 years were enrolled, and 170,800 patients were included in the final analysis. METHODS: BMI and clinical characteristics were assessed at baseline. PIs assessment were performed by trained nurses, with data recorded for the presence, the location and stage of each PI. For staging PIs, the National Pressure Ulcer Advisory Panelï¼NPUAPï¼ staging system were used. The multivariate logistic regressions analysis and restricted cubic splines (RCS) models were used to explore associations between BMI and PIs, adjusting for potential confounders. RESULTS: Of 175,960 participants, 5160 were excluded from analyses. The multivariate logistic regression model identified a positive relationship between under-weight BMI and risk of PIs occurrence (OR = 1.60, 95% CI:1.18-2.17). We also found U shaped association between BMI and PIs occurrence (non-linear P < 0.001). BMI less than 23 kg/m2 significantly increased risk of PIs, and there was a tendency to increase risk of PIs at BMI higher than 30 kg/m2. We stratified participants by sex to further investigate their association and found the risk of PIs increases substantially in women at BMI below 17 kg/m2 and in men at BMI below 23 kg/m2. CONCLUSIONS: The present study indicated that there was an approximate U shaped relationship between BMI and PIs occurrence, and this association was potentially different between men and women.
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Índice de Massa Corporal , Úlcera por Pressão , Humanos , Úlcera por Pressão/epidemiologia , Úlcera por Pressão/etiologia , Masculino , Feminino , Estudos Prospectivos , Pessoa de Meia-Idade , China/epidemiologia , Idoso , Adulto , Hospitalização/estatística & dados numéricos , Fatores de Risco , Modelos LogísticosRESUMO
Soil (or plant) water deficit accelerates plant reproduction. However, the underpinning molecular mechanisms remain unknown. By modulating cell division/number, ABSCISIC ACID-INSENSITIVE 5 (ABI5), a key bZIP (basic (region) leucine zippers) transcription factor, regulates both seed development and abiotic stress responses. The KIP-RELATED PROTEIN (KRP) cyclin-dependent kinases (CDKs) play an essential role in controlling cell division, and SHOOT MERISTEMLESS (STM) plays a key role in the specification of flower meristem identity. Here, our findings show that abscisic acid (ABA) signaling and/or metabolism in adjust reproductive outputs (such as rosette leaf number and open flower number) under water-deficient conditions in Arabidopsis (Arabidopsis thaliana) plants. Reproductive outputs increased under water-sufficient conditions but decreased under water-deficient conditions in the ABA signaling/metabolism mutants abscisic acid2-1 (aba2-1), aba2-11, abscisic acid insensitive3-1 (abi3-1), abi4-1, abi5-7, and abi5-8. Further, under water-deficient conditions, ABA induced-ABI5 directly bound to the promoter of KRP1, which encodes a CDK that plays an essential role in controlling cell division, and this binding subsequently activated KRP1 expression. In turn, KRP1 physically interacted with STM, which functions in the specification of flower meristem identity, promoting STM degradation. We further demonstrate that reproductive outputs are adjusted by the ABI5-KRP1-STM molecular module under water-deficient conditions. Together, our findings reveal the molecular mechanism by which ABA signaling and/or metabolism regulate reproductive development under water-deficient conditions. These findings provide insights that may help guide crop yield improvement under water deficiency.
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Ácido Abscísico , Proteínas de Arabidopsis , Arabidopsis , Flores , Regulação da Expressão Gênica de Plantas , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Ácido Abscísico/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/fisiologia , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Transdução de Sinais , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Reprodução , Mutação/genética , Quinases Ciclina-Dependentes/metabolismo , Quinases Ciclina-Dependentes/genética , Proteínas de HomeodomínioRESUMO
A stochastic Microcystins degradation model with distributed delay is studied in this paper. We first demonstrate the existence and uniqueness of a global positive solution to the stochastic system. Second, we derive a stochastic critical value $ R_0/ $ related to the basic reproduction number $ R_0 $. By constructing suitable Lyapunov function types, we obtain the existence of an ergodic stationary distribution of the stochastic system if $ R_0/ > 1. $ Next, by means of the method developed to solve the general four-dimensional Fokker-Planck equation, the exact expression of the probability density function of the stochastic model around the quasi-endemic equilibrium is derived, which is the key aim of the present paper. In the analysis of statistical significance, the explicit density function can reflect all dynamical properties of a chemostat model. To validate our theoretical conclusions, we present examples and numerical simulations.
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Fine particles (PM2.5) pollution is still a severe issue in some cities in China, where the chemical characteristics of PM2.5 remain unclear due to limited studies there. Herein, we focused on PM2.5 pollution in small and medium-sized cities in key urban agglomerations and conducted a comprehensive study on the PM2.5 chemical characteristics, sources, and health risks. In the autumn and winter of 2019-2020, PM2.5 samples were collected simultaneously in four small and medium-sized cities in four key regions: Dingzhou (Beijing-Tianjin-Hebei region), Weinan (Fenwei Plain region), Fukang (Northern Slope of the Tianshan Mountain region), and Bozhou (Yangtze River Delta region). The results showed that secondary inorganic ions (43.1 %-67.0 %) and organic matter (OM, 8.6 %-36.4 %) were the main components of PM2.5 in all the cities. Specifically, Fukang with the most severe PM2.5 pollution had the highest proportion of SO42- (31.2 %), while the dominant components in other cities were NO3- and OM. The Multilinear Engine 2 (ME2) analysis identified five sources of PM2.5 in these cities. Coal combustion contributed most to PM2.5 in Fukang, but secondary sources in other cities. Combined with chemical characteristics and ME2 analysis, it was preliminarily determined that the primary emission of coal combustion had an important contribution to high SO42- in Fukang. Potential source contribution function (PSCF) analysis results showed that regional transport played an important role in PM2.5 in Dingzhou, Weinan and Bozhou, while PM2.5 in Fukang was mainly affected by short-range transport from surrounding areas. Finally, the health risk assessment indicated Mn was the dominant contributor to the total non-carcinogenic risks and Cr had higher carcinogenic risks in all cities. The findings provide a scientific basis for formulating more effective abatement strategies for PM2.5 pollution.
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Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Cidades , Poluição do Ar/análise , Material Particulado/análise , Monitoramento Ambiental/métodos , China , Estações do Ano , Carvão Mineral/análiseRESUMO
Innovative solvents such as deep eutectic solvents (DESs) and process intensification technologies assisted by ultrasound have been demonstrated to be promising pathways for enhancing solid-liquid extraction. Nevertheless, quantitative and systematic knowledge of their environmental impact is still limited. In this work, a case study of flavonoids extraction from Ginkgo biloba leaves was evaluated by using life cycle assessment (LCA) for comparison of three extraction scenarios. The first used DES as extractant (DESE), and the other two adopted ethanol, including heat reflux extraction (HRE), and ultrasound-assisted extraction (UAE). Among eight key midpoints investigated, all these from UAE were 10.0 %-80.0 % lower than from DESE and HRE except water consumption. The UAE was the eco-friendliest option due to its higher extraction yield, shorter duration and lower solvent consumption. The DESE exhibited the lowest water consumption, the highest freshwater ecotoxicity and human carcinogenic toxicity, while HRE had the highest impacts for the other 6 midpoints. Moreover, solvent production was the key contributor for all the categories. The standardized sensitivity analysis showed that the overall environmental footprint can be further decreased by 15.4 % for DESE pathways via substituting choline chloride/glycerine with choline chloride/ethylene glycol. Furthermore, all pathways using DESs had higher standardized impacts than those employing ethanol from sugarcane or wood. Replacing ethanol from maize with other feedstocks can significantly lessen the overall impacts, among which the UAE using ethanol from sugarcane demonstrated the least environmental impacts. The promotion of DESs as "green and sustainable" alternative to traditional solvents requires careful consideration.
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Flavonoides , Ginkgo biloba , Humanos , Animais , Solventes , Extratos Vegetais , Etanol , Colina , Estágios do Ciclo de VidaRESUMO
Copper oxide nanoparticles (CuO NPs) influence the uptake of heavy metal ions by plants, but molecular mechanism is still unknown. Here, we proved the mechanism of CuO NPs affecting Cd absorption in Arabidopsis root. 4-d-old seedlings were treated by 10 and 20 mg/L CuO NPs for 3 d, which decreased the contents of cellulose and hemicellulose in roots. Moreover, the contents of some important monosaccharides were altered by CuO NPs, including arabinose, glucose and mannose. Biosynthesis of cellulose and hemicellulose is regulated by cellulose synthase A complexe (CSC) dynamics. The synthesis of tubulin cytoskeleton was inhibited by CuO NPs, which resulted in the decrease of CSCs bidirectional velocities. Furthermore, the arrangement and network of cellulose fibrillar bundles were disrupted by CuO NPs. CuO NPs treatment significantly increased the influx of Cd2+. The accumulation and translocation of Cd were increased by 10 and 20 mg/L CuO NPs treatment. The subcellular distribution of Cd in root cells indicated CuO NPs decrease the enrichment of Cd in cell wall, but increase the enrichment of Cd in soluble fraction and organelle. In light of these findings, we proposed a mechanistic model in which CuO NPs destroy the ordered structure of the cell wall, alter the uptake and distribution of Cd in Arabidopsis.