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1.
Medicine (Baltimore) ; 103(18): e38028, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701314

RESUMO

Liver hepatocellular carcinoma (LIHC) encompasses diverse therapeutic approaches, among which targeted therapy has gained significant prominence in recent years. The identification of numerous targets and the increasing clinical application of targeted drugs have greatly improved LIHC treatment. However, the precise role of CDCA4 (Cell Division Cycle Associated 4), as well as its underlying mechanisms and prognostic implications in LIHC, remains unclear. CDCA4 expression levels in LIHC were analyzed using multiple databases including the cancer genome atlas (TCGA), gene expression profiling interactive analysis (GEPIA), and ULCAN, as well as the datasets E_TABM_36, GSE144269, GSE14520, and GSE54236. The prognostic value of CDCA4 was then evaluated. Subsequently, the association between CDCA4 and immune cells was investigated. Enrichment analysis (GSEA) was utilized to investigate the functional roles and pathways linked to CDCA4. Additionally, the methylation patterns and drug sensitivity of CDCA4 were examined. A predictive model incorporating immune genes related to CDCA4 was developed. The TISCH dataset was used to investigate the single-cell expression patterns of CDCA4. Finally, validation of CDCA4 expression levels was conducted through RT-PCR, Western blotting, and immunohistochemistry. CDCA4 exhibited significant overexpression in LIHC and demonstrated significant correlations with clinical features. High expression of CDCA4 is associated with a poorer prognosis. Analysis of immune infiltration and enrichment revealed its association with the immune microenvironment. Furthermore, its expression is correlated with methylation and mutation patterns. CDCA4 is associated with 19 drugs. Prognostic models utilizing CDCA4 demonstrate favorable effectiveness. T cell subtypes were found to be associated with CDCA4 through single-cell analysis. The conclusive experiment provided evidence of significant upregulation of CDCA4 in LIHC. The high expression of CDCA4 in LIHC is associated with prognostic significance and is highly expressed in T cell subtypes, providing a new therapeutic target and potential therapeutic strategy for LIHC.


Assuntos
Carcinoma Hepatocelular , Proteínas de Ciclo Celular , Biologia Computacional , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Biologia Computacional/métodos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Prognóstico , Regulação Neoplásica da Expressão Gênica , Perfilação da Expressão Gênica , Masculino , Feminino , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo
2.
BMC Biol ; 20(1): 254, 2022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-36357887

RESUMO

BACKGROUND: Heat stress is a major abiotic stress affecting the growth and development of plants, including crop species. Plants have evolved various adaptive strategies to help them survive heat stress, including maintaining membrane stability, encoding heat shock proteins (HSPs) and ROS-scavenging enzymes, and inducing molecular chaperone signaling. Brassinosteroids (BRs) are phytohormones that regulate various aspects of plant development, which have been implicated also in plant responses to heat stress, and resistance to heat in Arabidopsis thaliana is enhanced by adding exogenous BR. Brassinazole resistant 1 (BZR1), a transcription factor and positive regulator of BR signal, controls plant growth and development by directly regulating downstream target genes. However, the molecular mechanism at the basis of BR-mediated heat stress response is poorly understood. Here, we report the identification of a new factor critical for BR-regulated heat stress tolerance. RESULTS: We identified ERF49 in a genetic screen for proteins required for BR-regulated gene expression. We found that ERF49 is the direct target gene of BZR1 and that overexpressing ERF49 enhanced sensitivity of transgenic plants to heat stress. The transcription levels of heat shock factor HSFA2, heat stress-inducible gene DREB2A, and three heat shock protein (HSP) were significantly reduced under heat stress in ERF49-overexpressed transgenic plants. Transcriptional activity analysis in protoplast revealed that BZR1 inhibits ERF49 expression by binding to the promoter of ERF49. Our genetic analysis showed that dominant gain-of-function brassinazole resistant 1-1D mutant (bzr1-1D) exhibited lower sensitivity to heat stress compared with wild-type. Expressing ERF49-SRDX (a dominant repressor reporter of ERF49) in bzr1-1D significantly decreased the sensitivity of ERF49-SRDX/bzr1-1D transgenic plants to heat stress compared to bzr1-1D. CONCLUSIONS: Our data provide clear evidence that BR increases thermotolerance of plants by repressing the expression of ERF49 through BZR1, and this process is dependent on the expression of downstream heat stress-inducible genes. Taken together, our work reveals a novel molecular mechanism mediating plant response to high temperature stress.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Termotolerância , Brassinosteroides , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Termotolerância/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Resposta ao Choque Térmico/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de Plantas
3.
Build Environ ; 224: 109530, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36065253

RESUMO

This study used Computational Fluid Dynamics (CFD) to investigate air disinfection for SARS-CoV-2 by the Upper-Room Germicidal Ultraviolet (UR-GUV), with focus on ceiling impact. The study includes three indoor settings, i.e., low (airport bus), medium (classroom) and high (rehearsal room) ceilings, which were ventilated with 100% clean air (CA case), 80% air-recirculation with a low filtration (LF case), and 80% air-recirculation with a high filtration (HF case). According to the results, using UR-GUV can offset the increased infection risk caused by air recirculation, with viral concentrations in near field (NF) and far field (FF) in the LF case similar to those in the CA case. In the CA case, fraction remaining (FR) was 0.48-0.73 with 25% occupancy rate (OR) and 0.49-0.91 with 45% OR in the bus, 0.41 in NF and 0.11 in FF in the classroom, and 0.18 in NF and 0.09 in FF in the rehearsal room. Obviously, UR-GUV performance in NF can be improved in a room with a high ceiling where FR has a power relationship with UV zone height. As using UR-GUV can only extend the exposure time to get infection risk of 1% (T 1% ) to 8 min in NF in the classroom, and 47 min in NF in the rehearsal room, it is necessary to abide by social distancing in the two rooms. In addition, T 1% in FF was calculated to be 18.3 min with 25% OR and 21.4% with 45% OR in the airport bus, showing the necessity to further wear a mask.

4.
Mol Plant Pathol ; 23(11): 1695-1700, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35951729

RESUMO

Being sessile in soil, plant cells rely on cell-surface receptors to sense and transduce environmental stimulus signals into intracellular responses. FERONIA (FER), a Catharanthus roseus receptor-like kinase 1-like protein, has emerged as a versatile regulator of plant growth, development, and stress responses. In recent years, accumulating studies have witnessed rapid advances in dissecting the mechanisms underlying the interaction between FER and its partners in response to pathogen invasion, particularly regulation of immune complex formation and signalling. Moreover, hormonal signalling, rhizosphere microbiota and other constituents are also extensively involved in these processes.


Assuntos
Proteínas de Arabidopsis , Complexo Antígeno-Anticorpo , Proteínas de Arabidopsis/metabolismo , Fosfotransferases/metabolismo , Transdução de Sinais , Solo
5.
Am J Transl Res ; 14(6): 4090-4096, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35836859

RESUMO

Chronic hepatitis B (CHB) as the major inducement of hepatocellular carcinoma and cirrhosis, imposes a heavy health burden upon patients. This research aims to investigate the diagnostic value of serum chitinase 3-like 1 (CHI3L1) in hepatitis B e antigen (HBeAg)-negative CHB liver fibrosis (LF) and to analyze the risk factors. We selected 78 patients with HBeAg-negative CHB admitted to our hospital between October 2018 and October 2019, and grouped them (F0,1 group, n=38; F2-4 group, n=40) based on their stages evaluated by the METAVIR scoring system. Cubital venous blood was collected from patients in both groups to quantify the content of CHI3L1 after serum extraction. The correlation of CHI3L1 in CHB with LF diagnostic markers fibrosis 4 (FIB-4) and γ-glutamyltranspeptidase (GGT) to platelet (PLT) ratio (GPR) as well as LF staging was analyzed. The diagnostic value of serum CHI3L1 in HBeAg-negative CHB fibrosis staging was analyzed by receiver operating characteristic (ROC) curve, and the multivariate analysis of the risk factors for FB in HBeAg-negative CHB patients was performed using the Logistic regression model. This study found that serum CHI3L1 was positively correlated not only with LF markers (FIB-4, GPR), but also with LF staging. Serum CHI3L1 had high diagnostic efficiency for LF staging, with the sensitivity and specificity of 80.00% and 71.05%, respectively. In addition, CHI3L1, FIB-4, and GPR were identified to be the risk factors for LF in HBeAg-negative CHB. In conclusion, serum CHI3L1 can be used as a diagnostic marker and risk factor for LF in patients with HBeAg-negative CHB.

6.
Plant J ; 111(3): 785-799, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35653239

RESUMO

The BRASSINAZOLE-RESISTANT (BZR) transcription factor is a core component of brassinosteroid (BR) signaling and is involved in the development of many plant species. BR is essential for the initiation and elongation of cotton fibers. However, the mechanism of BR-regulating fiber development and the function of BZR is poorly understood in Gossypium hirsutum L. (cotton). Here, we identified a BZR family transcription factor protein referred to as GhBZR3 in cotton. Overexpression of GhBZR3 in Arabidopsis caused shorter root hair length, hypocotyl length, and hypocotyl cell length, indicating that GhBZR3 negatively regulates cell elongation. Pathway enrichment analysis from VIGS-GhBZR3 cotton plants found that fatty acid metabolism and degradation might be the regulatory pathway that is primarily controlled by GhBZR3. Silencing GhBZR3 expression in cotton resulted in taller plant height as well as longer fibers. The very-long-chain fatty acid (VLCFA) content was also significantly increased in silenced GhBZR3 plants compared with the wild type. The GhKCS13 promoter, a key gene for VLCFA biosynthesis, contains two GhBZR3 binding sites. The results of yeast one-hybrid, electrophoretic mobility shift, and luciferase assays revealed that GhBZR3 directly interacted with the GhKCS13 promoter to suppress gene expression. Taken together, these results indicate that GhBZR3 negatively regulates cotton fiber development by reducing VLCFA biosynthesis. This study not only deepens our understanding of GhBZR3 function in cotton fiber development, but also highlights the potential of improving cotton fiber length and plant growth using GhBZR3 and its related genes in future cotton breeding programs.


Assuntos
Arabidopsis , Fibra de Algodão , Arabidopsis/genética , Brassinosteroides/metabolismo , Brassinosteroides/farmacologia , Ácidos Graxos/metabolismo , Regulação da Expressão Gênica de Plantas , Gossypium/metabolismo , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo
7.
Indoor Air ; 32(6): e13064, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35762243

RESUMO

The exhalation of aerosols during musical performances or rehearsals posed a risk of airborne virus transmission in the COVID-19 pandemic. Previous research studied aerosol plumes by only focusing on one risk factor, either the source strength or convective transport capability. Furthermore, the source strength was characterized by the aerosol concentration and ignored the airflow rate needed for risk analysis in actual musical performances. This study characterizes aerosol plumes that account for both the source strength and convective transport capability by conducting experiments with 18 human subjects. The source strength was characterized by the source aerosol emission rate, defined as the source aerosol concentration multiplied by the source airflow rate (brass 383 particle/s, singing 408 particle/s, and woodwind 480 particle/s). The convective transport capability was characterized by the plume influence distance, defined as the sum of the horizontal jet length and horizontal instrument length (brass 0.6 m, singing 0.6 m and woodwind 0.8 m). Results indicate that woodwind instruments produced the highest risk with approximately 20% higher source aerosol emission rates and 30% higher plume influence distances compared with the average of the same risk indicators for singing and brass instruments. Interestingly, the clarinet performance produced moderate source aerosol concentrations at the instrument's bell, but had the highest source aerosol emission rates due to high source airflow rates. Flute performance generated plumes with the lowest source aerosol emission rates but the highest plume influence distances due to the highest source airflow rate. Notably, these comprehensive results show that the source airflow is a critical component of the risk of airborne disease transmission. The effectiveness of masking and bell covering in reducing aerosol transmission is due to the mitigation of both source aerosol concentrations and plume influence distances. This study also found a musician who generated approximately five times more source aerosol concentrations than those of the other musicians who played the same instrument. Despite voice and brass instruments producing measurably lower average risk, it is possible to have an individual musician produce aerosol plumes with high source strength, resulting in enhanced transmission risk; however, our sample size was too small to make generalizable conclusions regarding the broad musician population.


Assuntos
Poluição do Ar em Ambientes Fechados , COVID-19 , Aerossóis e Gotículas Respiratórios , Canto , Aerossóis/análise , Poluição do Ar em Ambientes Fechados/análise , COVID-19/transmissão , Humanos , Música , Pandemias , Aerossóis e Gotículas Respiratórios/virologia
8.
Build Environ ; 219: 109186, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35599668

RESUMO

Airport transportation vehicles, such as buses, aerotrains, and shuttles, provide important passenger transfer services in airports. This study quantitatively investigated COVID-19 aerosol infection risk and identified acceptable operational conditions, such as passenger occupancy rates and duration of rides, given the performance of vehicle ventilation. The greatest risk to the largest number of passengers is from an index case whose exhaled breath would take the longest time to exit the vehicle. The study identified such a case based on ventilation patterns, and it tracked the spread of viral aerosols (5 µm) by using the Wells-Riley equation to predict aerosol infection risk distribution. These distributions allowed a definition of an imperfect mixing degree (δ) as the ratio of actual risk and the calculated risk under a perfect mixing condition, and further derived regression equations to predict δ in the far-field (FF) and near-field (NF) of each passenger. These results revealed an order of magnitude higher aerosol infection risk in NF than in FF. For example, with a ventilation rate of 58 ACH (air changes per hour) and a 45% occupancy rate, unmasked passengers should stay up to 15 min in the bus and 35 min in the shuttle to limit infection risk in NF within 10%. These also indicate that masking is an important and effective risk reduction measure in transportation vehicles, especially important in NF. Overall, the analysis of imperfect air mixing allows direct comparison of risks in different transportation vehicles and a structured approach to development of policy recommendations.

9.
Front Mol Biosci ; 8: 736272, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34917649

RESUMO

Background: Growing evidence has confirmed that populations with type 2 diabetes mellitus (T2DM) have an increasing risk of developing colorectal cancer (CRC). Thus, convenient and effective screening strategies for CRC should be developed for the T2DM population to increase the detection rate of CRC. Methods: Twenty serum samples extracted from five healthy participants, five T2DM patients, five CRC patients and five T2DM patients with CRC (T2DM + CRC) were submitted to data-independent acquisition mass spectrometry (DIA-MS) analysis to discover unique differentially altered proteins (DAPs) for CRC in patients with T2DM. Then, the diagnostic value of pregnancy zone protein (PZP) was validated by ELISA analysis in the validated cohort. Results: Based on DIA-MS analysis, we found eight unique proteins specific to T2DM patients with CRC. Among these proteins, four proteins showed different expression between the T2DM + CRC and T2DM groups, and PZP exhibited the largest difference. Next, the diagnostic value of serum PZP was validated by ELISA analysis with an AUC of 0.713. Moreover, the combination of PZP, CA199 and CEA exhibited encouraging diagnostic value, and the AUC reached 0.916. Conclusion: Overall, our current research implied that PZP could be regarded as a newfound serum biomarker for CRC medical diagnosis in T2DM patients.

10.
ACS Environ Au ; 1(1): 71-84, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37155479

RESUMO

Outbreaks from choir performances, such as the Skagit Valley Choir, showed that singing brings potential risk of COVID-19 infection. There is less known about the risks of airborne infection from other musical performances, such as playing wind instruments or performing theater. In addition, it is important to understand methods that can be used to reduce infection risk. In this study, we used a variety of methods, including flow visualization, aerosol and CO2 measurements, and computational fluid dynamics (CFD) modeling to understand the different components that can lead to transmission risk from musical performance and risk mitigation. This study was possible because of a partnership across academic departments and institutions and collaboration with the National Federation of State High School Associations and the College Band Directors National Association. The interdisciplinary team enabled us to understand the various aspects of aerosol transmission risk from musical performance and to quickly implement strategies in music classrooms during the COVID-19 pandemic. We found that plumes from musical performance were highly directional, unsteady and varied considerably in time and space. Aerosol number concentration measured at the bell of the clarinet was comparable to that of singing. Face and bell masks attenuated plume velocities and lengths and decreased aerosol concentrations measured in front of the masks. CFD modeling showed differences between indoor and outdoor environments and that the lowest risk of airborne COVID-19 infection occurred at less than 30 min of exposure indoors and less than 60 min outdoors.

11.
Med Res Rev ; 41(2): 1061-1088, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33174230

RESUMO

In a complex, diverse intestinal environment, commensal microbiota metabolizes excessive dietary tryptophan to produce more bioactive metabolites connecting with kinds of diverse process, such as host physiological defense, homeostasis, excessive immune activation and the progression and outcome of different diseases, such as inflammatory bowel disease, irritable bowel syndrome and others. Although commensal microbiota includes bacteria, fungi, and protozoa and all that, they often have the similar metabolites in tryptophan metabolism process via same or different pathways. These metabolites can work as signal to activate the innate immunity of intestinal mucosa and induce the rapid inflammation response. They are critical in reconstruction of lumen homeostasis as well. This review aims to seek the potential function and mechanism of microbiota-derived tryptophan metabolites as targets to regulate and shape intestinal immune function, which mainly focused on two aspects. First, analyze the character of tryptophan metabolism in bacteria, fungi, and protozoa, and assess the functions of their metabolites (including indole and eight other derivatives, serotonin (5-HT) and d-tryptophan) on regulating the integrity of intestinal epithelium and the immunity of the intestinal mucosa. Second, focus on the mediator and pathway for their recognition, transfer and crosstalk between microbiota-derived tryptophan metabolites and intestinal mucosal immunity. Disruption of intestinal homeostasis has been described in different intestinal inflammatory diseases, available data suggest the remarkable potential of tryptophan-derived aryl hydrocarbon receptor agonists, indole derivatives on lumen equilibrium. These metabolites as preventive and therapeutic interventions have potential to promote proinflammatory or anti-inflammatory responses of the gut.


Assuntos
Microbioma Gastrointestinal , Microbiota , Humanos , Imunidade nas Mucosas , Inflamação , Mucosa Intestinal , Triptofano
12.
Medicine (Baltimore) ; 99(37): e22092, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32925750

RESUMO

Pancreatic cancer (PaCa) is one of the most fatal cancers in the world. Although great efforts have made to explore the mechanisms of PaCa oncogenesis, the prognosis of PaCa patients is still unsatisfactory. Thus, it is imperative to further understand the potential carcinogenesis of PaCa and reliable prognostic models.The gene expression profile and clinical information of GSE21501 were downloaded from the Gene Expression Omnibus (GEO) database. Weighted gene co-expression network analysis (WGCNA) was applied to explore the potent genes associated with the overall survival (OS) events of PaCa patients. Cox regression model was applied to selecting prognostic genes and establish prognostic model. The prognostic values of six-gene signature were validated in TCGA-PAAD cohort.According to the WGCNA analysis, a total of 19 modules were identified and 115 hub genes in the mostly associated module were reserved for next analysis. According to the univariate and multivariate Cox regression analysis, we established a six-gene signature (FTSJ3, STAT1, STX2, CDX2, RASSF4, MACF1) which could effectively evaluate the overall survival (OS) of PaCa patients. In validated patients' cohorts, the six-gene signature exhibited excellent prognostic value in TCGA-PAAD cohort as well.We developed a six-gene signature to exactly predict OS of PaCa patients and provide a novel personalized strategy for evaluating prognosis. The findings may be contributed to medical customization and therapeutic decision in clinical practice.


Assuntos
Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/mortalidade , Fator de Transcrição CDX2/genética , Perfilação da Expressão Gênica , Humanos , Metiltransferases/genética , Proteínas dos Microfilamentos/genética , Modelos Estatísticos , Neoplasias Pancreáticas/patologia , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Fator de Transcrição STAT1/genética , Sintaxina 1/genética , Proteínas Supressoras de Tumor/genética
13.
Environ Int ; 137: 105537, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32028176

RESUMO

Strategies to protect building occupants from the risk of acute respiratory infection (ARI) need to consider ventilation for its ability to dilute and remove indoor bioaerosols. Prior studies have described an association of increased self-reported colds and influenza-like symptoms with low ventilation but have not combined rigorous characterization of ventilation with assessment of laboratory confirmed infections. We report a study designed to fill this gap. We followed laboratory confirmed ARI rates and measured CO2 concentrations for four months during the winter-spring of 2018 in two campus residence halls: (1) a high ventilation building (HVB) with a dedicated outdoor air system that supplies 100% of outside air to each dormitory room, and (2) a low ventilation building (LVB) that relies on infiltration as ventilation. We enrolled 11 volunteers for a total of 522 person-days in the HVB and 109 volunteers for 6069 person-days in the LVB, and tested upper-respiratory swabs from symptomatic cases and their close contacts for the presence of 44 pathogens using a molecular assay. We observed one ARI case in the HVB (0.70/person-year) and 47 in the LVB (2.83/person-year). Simultaneously, 154 CO2 sensors distributed primarily in the dormitory rooms collected 668,390 useful data points from over 1 million recorded data points. Average and standard deviation of CO2 concentrations were 1230 ppm and 408 ppm in the HVB, and 1492 ppm and 837 ppm in the LVB, respectively. Importantly, this study developed and calibrated multi-zone models for the HVB with 229 zones and 983 airflow paths, and for the LVB with 529 zones and 1836 airflow paths by using a subset of CO2 data for model calibration. The models were used to calculate ventilation rates in the two buildings and potential for viral aerosol migration between rooms in the LVB. With doors and windows closed, the average ventilation rate was 12 L/s in the HVB dormitory rooms and 4 L/s in the LVB dormitory rooms. As a result, residents had on average 6.6 L/(s person) of outside air in the HVB and 2.3 L/(s person) in the LVB. LVB rooms located at the leeward side of the building had smaller average ventilation rates, as well as a somewhat higher ARI incidence rate and average CO2 concentrations when compared to those values in the rooms located at the windward side of the building. Average ventilation rates in twenty LVB dormitory rooms increased from 2.3 L/s to 7.5 L/s by opening windows, 3.6 L/s by opening doors, and 8.8 L/s by opening both windows and doors. Therefore, opening both windows and doors in the LVB dormitory rooms can increase ventilation rates to the levels comparable to those in the HVB. But it can also have a negative effect on thermal comfort due to low outdoor temperatures. Simulation results identified an aerobiologic pathway from a room occupied by an index case of influenza A to a room occupied by a possible secondary case.


Assuntos
Poluição do Ar em Ambientes Fechados , Infecções Respiratórias , Poluição do Ar em Ambientes Fechados/análise , Feminino , Habitação , Humanos , Masculino , Maryland , Infecções Respiratórias/epidemiologia , Estudantes , Temperatura , Universidades , Ventilação , Adulto Jovem
14.
Int J Mol Sci ; 21(4)2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32074966

RESUMO

MicroRNAs (miRNAs) are small molecule RNAs widely involved in responses to plant abiotic stresses. We performed small RNA sequencing of cotton anthers at four developmental stages under normal and high temperature (NT and HT, respectively) conditions to investigate the stress response characteristics of miRNA to HT. A total of 77 miRNAs, including 33 known miRNAs and 44 novel miRNAs, were identified, and 41 and 28 miRNAs were differentially expressed under NT and HT stress conditions, respectively. The sporogenous cell proliferation (SCP), meiotic phase (MP), microspore release period (MRP), and pollen maturity (PM) stages had 10 (including 12 miRNAs), four (including six miRNAs), four (including five miRNAs), and seven (including 11 miRNAs) HT stress-responsive miRNA families, respectively, which were identified after removing the changes in genotype-specific miRNAs under NT condition. Seven miRNA families (miR2949, miR167, and miR160 at the SCP stage; miR156 and miR172 at the MP stage; miR156 at the MRP stage; and miR393 and miR3476 at the PM stage), which had expression abundance of more than 10% of the total expression abundance, served as the main regulators responding to HT stress with positive or negative regulation patterns. These miRNAs orchestrated the expression of the corresponding target genes and led to different responses in the HT-tolerant and the HT-sensitive lines. The results revealed that the HT stress response of miRNAs in cotton anthers were stage-specific and differed with the development of anthers. Our study may enhance the understanding of the response of miRNAs to HT stress in cotton anthers and may clarify the mechanism of plant tolerance to HT stress.


Assuntos
Gossypium/genética , MicroRNAs/metabolismo , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Genótipo , Gossypium/crescimento & desenvolvimento , RNA de Plantas/química , RNA de Plantas/metabolismo , Análise de Sequência de RNA , Estresse Fisiológico , Temperatura
15.
Environ Int ; 120: 431-442, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30138888

RESUMO

This paper presents concentrations of common SVOCs in house dusts from urban dwellings with schoolchildren in six typical Chinese cities in winter and summer. Among the detected SVOCs, DBP and DEHP have a higher detection rate. The levels of these two substances contribute an average proportion of over 90% of the total SVOCs' levels, and show a significant correlation in most cities. Based on measured concentrations, schoolchildren's non-dietary exposures to DBP and DEHP at homes are estimated. Due to a longer time spent in child's bedrooms, children's non-dietary exposures to phthalates in child's bedrooms are greatly higher than that in living rooms. As for DBP non-dietary exposure, the most significant pathway is dermal absorption from air, accounting for >70%, whereas, the most predominant pathway for DEHP non-dietary exposure is dust ingestion, contributing from 61.5% to 91.9%. Based on estimated exposure doses, child-specific reproductive and cancer risk are assessed by comparing the exposure doses with DBP and DEHP benchmarks specified in California's Proposition 65. Owing to the high DBP exposure, nearly all of target schoolchildren appear to have a severe reproductive risk, although only non-dietary exposures at home are considered in this study. The average risk quotient of DBP exposure for child-specific MADL in all cities is 31.27 in winter and 10.35 in summer. Also, some schoolchildren are confronted with potential carcinogenic risk, because DEHP exposure exceeds child-specific NSRLs. The maximum DEHP exposure exceeds the cancer benchmark by over 6 times. These results also indicate that controlling indoor phthalates pollution at home is urgent to ensure the healthy development of children in China.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Poeira/análise , Exposição Ambiental/análise , Poluentes Ambientais/análise , Ácidos Ftálicos/análise , Compostos Orgânicos Voláteis/análise , Criança , China , Cidades , Ingestão de Alimentos , Feminino , Humanos , Masculino , Neoplasias , Medição de Risco , Absorção Cutânea
16.
Mol Cell ; 66(5): 648-657.e4, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28575660

RESUMO

The glycogen synthase kinase-3 (GSK3) family kinases are central cellular regulators highly conserved in all eukaryotes. In Arabidopsis, the GSK3-like kinase BIN2 phosphorylates a range of proteins to control broad developmental processes, and BIN2 is degraded through unknown mechanism upon receptor kinase-mediated brassinosteroid (BR) signaling. Here we identify KIB1 as an F-box E3 ubiquitin ligase that promotes the degradation of BIN2 while blocking its substrate access. Loss-of-function mutations of KIB1 and its homologs abolished BR-induced BIN2 degradation and caused severe BR-insensitive phenotypes. KIB1 directly interacted with BIN2 in a BR-dependent manner and promoted BIN2 ubiquitination in vitro. Expression of an F-box-truncated KIB1 caused BIN2 accumulation but dephosphorylation of its substrate BZR1 and activation of BR responses because KIB1 blocked BIN2 binding to BZR1. Our study demonstrates that KIB1 plays an essential role in BR signaling by inhibiting BIN2 through dual mechanisms of blocking substrate access and promoting degradation.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/efeitos dos fármacos , Brassinosteroides/farmacologia , Proteínas F-Box/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Plantas Geneticamente Modificadas/efeitos dos fármacos , Proteínas Quinases/metabolismo , Esteroides Heterocíclicos/farmacologia , Ubiquitina-Proteína Ligases/metabolismo , Arabidopsis/enzimologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Sítios de Ligação , Domínio Catalítico , Proteínas de Ligação a DNA , Ativação Enzimática , Estabilidade Enzimática , Proteínas F-Box/genética , Genótipo , Quinase 3 da Glicogênio Sintase/genética , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fenótipo , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Proteínas Quinases/genética , Proteólise , Transdução de Sinais/efeitos dos fármacos , Especificidade por Substrato , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
17.
Sci Rep ; 6: 32729, 2016 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-27601353

RESUMO

SET (Su(var), E(z), and Trithorax) domain-containing proteins play an important role in plant development and stress responses through modifying lysine methylation status of histone. Gossypium raimondii may be the putative contributor of the D-subgenome of economical crops allotetraploid G. hirsutum and G. barbadense and therefore can potentially provide resistance genes. In this study, we identified 52 SET domain-containing genes from G. raimondii genome. Based on conserved sequences, these genes are grouped into seven classes and are predicted to catalyze the methylation of different substrates: GrKMT1 for H3K9me, GrKMT2 and GrKMT7 for H3K4me, GrKMT3 for H3K36me, GrKMT6 for H3K27me, but GrRBCMT and GrS-ET for nonhistones substrate-specific methylation. Seven pairs of GrKMT and GrRBCMT homologous genes are found to be duplicated, possibly one originating from tandem duplication and five from a large scale or whole genome duplication event. The gene structure, domain organization and expression patterns analyses suggest that these genes' functions are diversified. A few of GrKMTs and GrRBCMTs, especially for GrKMT1A;1a, GrKMT3;3 and GrKMT6B;1 were affected by high temperature (HT) stress, demonstrating dramatically changed expression patterns. The characterization of SET domain-containing genes in G. raimondii provides useful clues for further revealing epigenetic regulation under HT and function diversification during evolution.


Assuntos
Gossypium/crescimento & desenvolvimento , Proteínas de Plantas/química , Proteínas de Plantas/genética , Estresse Fisiológico , Sequência de Bases , Mapeamento Cromossômico , Sequência Conservada , Evolução Molecular , Regulação da Expressão Gênica de Plantas , Gossypium/genética , Gossypium/metabolismo , Temperatura Alta , Metilação , Família Multigênica , Domínios PR-SET , Proteínas de Plantas/metabolismo
18.
J Appl Toxicol ; 36(4): 596-608, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26304222

RESUMO

Recent studies have shown that fine particulate matter (PM2.5) is associated with multiple adverse health outcomes and PM2.5-induced oxidative stress is now commonly known as a proposed mechanism of PM2.5-mediated toxicity. However, the association between allergic symptoms in children and exposure to PM2.5 has not been fully elucidated, particularly the role of PM2.5 on the indoor environment involved in allergy or non-allergy is unknown. The aim of the present study was to explore whether indoor PM2.5 from the homes of children with allergic symptoms had more increased risks of allergy than that of healthy ones and then compare the toxicity and inflammatory response of them. In this study, indoor PM2.5 was collected from the homes of schoolchildren with allergic symptoms and those of healthy ones respectively, and components of PM2.5 were analyzed. PM2.5-mediated oxidative damage and inflammatory response were further evaluated in mouse peritoneal macrophages based on its effects on the levels of reactive oxygen species accumulation, lipid peroxidation, DNA damage or cytokine production. It seems that oxidative stress may contribute to PM2.5-induced toxicity, and PM2.5 from the allergic indoor environment produced more serious toxic effects and an inflammatory response on mouse peritoneal macrophages than that from a non-allergic indoor environment.


Assuntos
Poluentes Atmosféricos/toxicidade , Hipersensibilidade/epidemiologia , Macrófagos Peritoneais/efeitos dos fármacos , Material Particulado/toxicidade , Poluição do Ar em Ambientes Fechados , Animais , Células Cultivadas , Criança , China , Dano ao DNA/efeitos dos fármacos , Feminino , Glutationa/análise , Humanos , Interleucina-8/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
19.
J Integr Plant Biol ; 58(5): 442-51, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26178734

RESUMO

Vascular tissues are very important for providing both mechanical strength and long-distance transport. The molecular mechanisms of regulation of vascular tissue development are still not fully understood. In this study we identified ANAC005 as a membrane-associated NAC family transcription factor that regulates vascular tissue development. Reporter gene assays showed that ANAC005 was expressed mainly in the vascular tissues. Increased expression of ANAC005 protein in transgenic Arabidopsis caused dwarf phenotype, reduced xylem differentiation, decreased lignin content, repression of a lignin biosynthetic gene and genes related to cambium and primary wall, but activation of genes related to the secondary wall. Expression of a dominant repressor fusion of ANAC005 had overall the opposite effects on vascular tissue differentiation and lignin synthetic gene expression. The ANAC005-GFP fusion protein was localized at the plasma membrane, whereas deletion of the last 20 amino acids, which are mostly basic, caused its nuclear localization. These results indicate that ANAC005 is a cell membrane-associated transcription factor that inhibits xylem tissue development in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Feixe Vascular de Plantas/crescimento & desenvolvimento , Feixe Vascular de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Diferenciação Celular/genética , Membrana Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Fluorescência Verde/metabolismo , Morfogênese , Fenótipo , Frações Subcelulares/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/genética , Xilema/citologia , Xilema/metabolismo
20.
Build Environ ; 72: 116-124, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24426180

RESUMO

This study proposes a numerical modeling method for the indoor environment with ceiling fans and upper-room ultraviolet germicidal irradiation (UR-UVGI) fixtures. The numerical modeling deployed steady-state Computational Fluid Dynamics (CFD) with a rotating reference frame to simulate the rotation of fan blades. CFD was validated with experimental data of velocity field and fraction of microorganism remaining at the exhaust diffuser. The fraction of microorganism remaining represented the ratio of the concentration of airborne microorganisms measured with UVGI turned on to the one measured with UVGI turned off. According to the validation results, the CFD model correctly reproduced the air movement induced by the rotation of ceiling fan. When the ambient ventilation rate was 2 ACH (air changes per hour) or 6 ACH, the CFD model accurately predicted the average vertical speeds in the section 2.44 m above the floor with the errors less than 10%, regardless of the ceiling fan's rotational direction or speed. In addition, the simulation results showed that the fraction of microorganism remaining increased with the ambient air exchange rate when the fan blew air downward with a rotational speed as high as 235 rpm, which corresponded with the experimental results. Furthermore, the simulation results accurately predicted the fraction of microorganism remaining when the ambient air exchange rate was 2 ACH. We conclude that this novel numerical model can reproduce the effects of ceiling fans and UR-UVGI fixtures on indoor environment, and should aid in the investigation of the impact of ceiling fans on UR-UVGI disinfection efficacy.

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