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1.
Sci Data ; 11(1): 348, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582912

RESUMO

Check dams on the Chinese Loess Plateau (CLP) have captured billions of tons of eroded sediment, substantially reducing sediment load in the Yellow River. However, uncertainties persist regarding the precise sediment capture and the role of these dams in Yellow River flow and sediment dynamics due to the lack of available spatial distribution datasets. We produced the first vectorized dataset of silted land formed by check dams on the CLP, combining high-resolution and easily accessible Google Earth images with object-based classification methods. The accuracy of the dataset was verified by 1947 collected test samples, and the producer's accuracy and user's accuracy of the dam lands were 88.9% and 99.5%, respectively. Our dataset not only provides fundamental information for accurately assessing the ecosystem service functions of check dams, but also helps to interpret current changes in sediment delivery of the Yellow River and plan future soil and water conservation projects.

2.
Appl Spectrosc ; : 37028241245136, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38646741

RESUMO

Two-dimensional correlation spectroscopy is used to investigate the intermolecular interaction between two substances dissolved in the same solutions, where the intermolecular interaction is described by two reversible reactions producing two supramolecular aggregates. The severe overlappings expected among the characteristic peaks of the original solute and aggregates make conventional one-dimensional spectra difficult to accurately reflect the physiochemical nature of the intermolecular interaction. The double asynchronous orthogonal sample design (DAOSD) approach is utilized to analyze the simulated data for proof-of-principle demonstration. The patterns of cross-peaks are much more complex compared with the intermolecular interaction described by only a single reaction. Four major groups of cross-peaks with characteristic patterns observed in the pair of DAOSD asynchronous spectra are systematically analyzed and classified. Further analysis of the spectral feature of the cross-peaks of the DAOSD asynchronous spectra is helpful to exact additional information concerning the variation of the peak position and peak width of the aggregates compared with those of the original solute. The result is important to reveal the physicochemical nature of intermolecular interaction between the solutes (e.g., changes in conformation, dynamical behavior, etc.). The pattern of cross-peaks in the corresponding 2D asynchronous spectra may become rather complex when the peak position, peak width, and peak intensity of two supramolecular aggregates change simultaneously. Further work using artificial intelligence techniques to interpret the complex cross-peaks is still being carried out.

3.
bioRxiv ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38562704

RESUMO

Co-transcriptional alternate processing of nascent mRNA molecules can make major contributions to cell type specific gene expression programs as proliferating precursor cells initiate terminal differentiation. Alternative Cleavage and Polyadenylation (APA) can result in the production of mRNA isoforms from the same gene locus with either longer or shorter 3'UTRs. In Drosophila spermatogenesis, approximately 500 genes undergo APA as proliferating spermatogonia differentiate into spermatocytes, producing transcript isoforms with shortened 3'UTRs, and resulting in profound stage specific changes in the proteins expressed. The molecular mechanisms that specify usage of upstream polyadenylation sites in spermatocytes are thus key to understanding the changes in cell state. Here, we show that PCF11 and Cbc, the two components of Cleavage factor II (CFII), orchestrate APA switching during Drosophila spermatogenesis. Knockdown of PCF11 or cbc in spermatocytes caused dysregulation of APA, with many transcripts normally cleaved at a proximal site in spermatocytes now cleaved at their distal site, as in spermatogonia. Although PCF11 is widely expressed, cbc is strongly upregulated in spermatocytes. Our findings reveal a developmental mechanism where changes in activity of specific cleavage factors can direct cell type specific APA at selected genes, presenting CFII as a key developmental regulator of APA during spermatogenesis.

4.
Environ Res ; 252(Pt 1): 118868, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38580003

RESUMO

BACKGROUND: Previous research has shown that lack of leisure activities, either outdoor or social activities, impedes cognitive function. However, the interrelationship between poor cognition and deficient activities is understudied. In addition, whether exposure to air pollution, such as PM2.5, can accelerate the detrimental 'inactivity-poor cognition' cycle, is worthy of investigation. METHODS: We used data from the 2008, 2011, 2014, and 2018 waves of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). We assessed the frequency of outdoor or social activities at each wave. The cognitive function was examined using a China-Modified Mini-mental State Examination. We estimated the residential exposure to fine particular matter (PM2.5) via a satellite-based model. We applied cross-lagged panel (CLP) model to examine the bi-directional relationship between outdoor or social activities and cognitive function. We then examined the effect of PM2.5 exposure with sequent cognitive function and activities using generalized estimation equation (GEE) model. FINDINGS: Overall, we observed significant bi-directional associations between outdoor or social activities and cognitive function. Participants with better cognitive function in the last wave were more likely to engage in outdoor or social activities in the following wave (outdoor activities: ß = 0.37, 95% CI [0.27,0.48], P < 0.01; social activities: ß = 0.05, 95% CI [0.02,0.09] P < 0.01). Meanwhile, higher engagement in outdoor or social activities in the last wave was associated with more favorable cognitive function in the following wave (outdoor activities: ß = 0.06, 95% CI [0.03,0.09], P < 0.01; social activities: ß = 0.10, 95% CI [0.03,0.18], P < 0.01). Notably, an increase in PM2.5 exposure during the preceding year was significantly associated with a declining cognitive function (ß = -0.05, 95% CI [-0.08,-0.03], P < 0.01), outdoor activities (ß = -0.02, 95% CI [-0.04, -0.01], P < 0.01) and social activities (ß = -0.02, 95% CI [-0.02, -0.01], P < 0.01) in the current year; the lagged effects of the PM2.5 exposure in the past year of the last wave on activities and cognitive function of the following wave were also observed. INTERPRETATION: Our findings not only indicate the bi-directional links between the frequency of outdoor or social activities and cognitive function, but also report that PM2.5 exposure plays a role in catalyzing the detrimental inactivity-poor cognition cycle. Future research should investigate whether the policy-driven interventions, such as clean air policies, can break the unfavorable activity-cognition cycle, and thereby promoting health from the dual gains in leisure activities and cognition.

5.
Adv Sci (Weinh) ; : e2400736, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639415

RESUMO

For decreasing the global cost of corrosion, it is essential to understand the intricate mechanisms of corrosion and enhance the corrosion resistance of materials. However, the ambiguity surrounding the dominant mechanism of calcium-magnesium aluminosilicate (CMAS) molten salt corrosion in extreme environments hinders the mix-and-matching of the key rare earth elements for increasing the resistance of monosilicates against corrosion of CMAS. Herein, an approach based on correlated electron microscopy techniques combined with density functional theory calculations is presented to elucidate the complex interplay of competing mechanisms that control the corrosion of CMAS of monosilicates. These findings reveal a competition between thermodynamics and kinetics that relies on the temperatures and corrosion processes. Innovative medium-entropy monosilicates with exceptional corrosion resistance even at 1500 °C are developed. This is achieved by precisely modulating the radii of rare earth ions in monosilicates to strike a delicate balance between the competition in thermodynamics and kinetics. After 50 and 100 h of corrosion, the thinnest reactive layers are measured to be only 28.8 and 35.4 µm, respectively.

6.
Chem Commun (Camb) ; 60(33): 4475-4478, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38563956

RESUMO

A hydrogen-bonded organic framework (HOF) consisting of a 9,10-diphenylanthracene carboxylic derivative, DPACOOH, was developed for solid state triplet-triplet annihilation upconversion (TTA-UC). The HOF sample shows a 70% increase in upconversion quantum yield and a lower threshold value of 126.0 mW cm-2 compared to those of the disordered powder sample, due to a 43% longer triplet diffusion length in HOF than that in the powder sample.

7.
Nat Commun ; 15(1): 3221, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622129

RESUMO

The hippocampus creates a cognitive map of the external environment by encoding spatial and self-motion-related information. However, it is unclear whether hippocampal neurons could also incorporate internal cognitive states reflecting an animal's exploratory intention, which is not driven by rewards or unexpected sensory stimuli. In this study, a subgroup of CA1 neurons was found to encode both spatial information and animals' investigatory intentions in male mice. These neurons became active before the initiation of exploration behaviors at specific locations and were nearly silent when the same fields were traversed without exploration. Interestingly, this neuronal activity could not be explained by object features, rewards, or mismatches in environmental cues. Inhibition of the lateral entorhinal cortex decreased the activity of these cells during exploration. Our findings demonstrate that hippocampal neurons may bridge external and internal signals, indicating a potential connection between spatial representation and intentional states in the construction of internal navigation systems.


Assuntos
Intenção , Navegação Espacial , Masculino , Camundongos , Animais , Percepção Espacial/fisiologia , Hipocampo/fisiologia , Córtex Entorrinal , Sinais (Psicologia) , Navegação Espacial/fisiologia
8.
Eur Heart J ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38626306

RESUMO

BACKGROUND AND AIMS: Emerging evidence has raised an obesity paradox in observational studies of body mass index (BMI) and health among the oldest-old (aged ≥80 years), as an inverse relationship of BMI with mortality was reported. This study was to investigate the causal associations of BMI, waist circumference (WC), or both with mortality in the oldest-old people in China. METHODS: A total of 5306 community-based oldest-old (mean age 90.6 years) were enrolled in the Chinese Longitudinal Healthy Longevity Survey (CLHLS) between 1998 and 2018. Genetic risk scores were constructed from 58 single-nucleotide polymorphisms (SNPs) associated with BMI and 49 SNPs associated with WC to subsequently derive causal estimates for Mendelian randomization (MR) models. One-sample linear MR along with non-linear MR analyses were performed to explore the associations of genetically predicted BMI, WC, and their joint effect with all-cause mortality, cardiovascular disease (CVD) mortality, and non-CVD mortality. RESULTS: During 24 337 person-years of follow-up, 3766 deaths were documented. In observational analyses, higher BMI and WC were both associated with decreased mortality risk [hazard ratio (HR) 0.963, 95% confidence interval (CI) 0.955-0.971 for a 1-kg/m2 increment of BMI and HR 0.971 (95% CI 0.950-0.993) for each 5 cm increase of WC]. Linear MR models indicated that each 1 kg/m2 increase in genetically predicted BMI was monotonically associated with a 4.5% decrease in all-cause mortality risk [HR 0.955 (95% CI 0.928-0.983)]. Non-linear curves showed the lowest mortality risk at the BMI of around 28.0 kg/m2, suggesting that optimal BMI for the oldest-old may be around overweight or mild obesity. Positive monotonic causal associations were observed between WC and all-cause mortality [HR 1.108 (95% CI 1.036-1.185) per 5 cm increase], CVD mortality [HR 1.193 (95% CI 1.064-1.337)], and non-CVD mortality [HR 1.110 (95% CI 1.016-1.212)]. The joint effect analyses indicated that the lowest risk was observed among those with higher BMI and lower WC. CONCLUSIONS: Among the oldest-old, opposite causal associations of BMI and WC with mortality were observed, and a body figure with higher BMI and lower WC could substantially decrease the mortality risk. Guidelines for the weight management should be cautiously designed and implemented among the oldest-old people, considering distinct roles of BMI and WC.

9.
Nat Commun ; 15(1): 2394, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493141

RESUMO

We demonstrate a transcriptional regulatory design algorithm that can boost expression in yeast and mammalian cell lines. The system consists of a simplified transcriptional architecture composed of a minimal core promoter and a synthetic upstream regulatory region (sURS) composed of up to three motifs selected from a list of 41 motifs conserved in the eukaryotic lineage. The sURS system was first characterized using an oligo-library containing 189,990 variants. We validate the resultant expression model using a set of 43 unseen sURS designs. The validation sURS experiments indicate that a generic set of grammar rules for boosting and attenuation may exist in yeast cells. Finally, we demonstrate that this generic set of grammar rules functions similarly in mammalian CHO-K1 and HeLa cells. Consequently, our work provides a design algorithm for boosting the expression of promoters used for expressing industrially relevant proteins in yeast and mammalian cell lines.


Assuntos
Células Eucarióticas , Saccharomyces cerevisiae , Animais , Humanos , Saccharomyces cerevisiae/genética , Células HeLa , Regiões Promotoras Genéticas/genética , Expressão Gênica , Mamíferos/genética
10.
J Med Educ Curric Dev ; 11: 23821205241226818, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38532855

RESUMO

Objective: To evaluate the effect of the uncertainty training on improvement of students' diagnostic ability. Methods: Data were collected on 70 fifth-year medical students enrolled in the Case Discussion courses on Obstetrics and Gynecology in the spring of 2020. Of these students, 36 were in the uncertainty training group and 34 in the control group. The effect of training was evaluated by cognitively diagnostic assessment which mapped exam questions to 4 attributes assessing clinical reasoning and basic science knowledge. Results: Uncertainty training was able to improve students' ability to use basic science concepts for inference and problem solving, and the ability to integrate complex clinical information to arrive at a diagnosis. But it could not improve students' ability on the basic recall of foundational concepts and the ability to use basic science concepts in clinical reasoning. Medical students could do well in integrating complex clinical information although they didn't recall basic science knowledge well. Conclusion: Uncertainty training could be used as an effective teaching method in Case Discussion course on Obstetrics and Gynecology. However, students still need to improve their basic knowledge besides the training.

11.
Heliyon ; 10(6): e27899, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38500990

RESUMO

Aims: To synthesize the influencing factors of the stigma of nursing students towards people with mental illness (PMI). Background: The stigma of nursing students towards PMI may affect their career choices and negatively impact people seeking health services. While many studies have examined the educational aspects of mental health, they often overlook the multiple dimensions of possible factors influencing nursing students' perceptions. Design: A mixed-method systematic review using the Framework Integrating Normative Influences on Stigma (FINIS). Methods: We will search six databases, including PubMed, Web of Science, Cochrane Library, EMBASE, CINAHL and PsycINFO. The reference list of the included literature will be thoroughly examined to identify if any additional studies meet the criteria. Two authors will independently screen all titles, abstracts, full text and extract data. The Mixed-method Appraisal Tool will be used to assess quality. The extracted data will be disposed to different levels, including micro (demographic characteristics, disease characteristics), meso (social networks, treatment systems) and macro (media images, national context) to comply with the FINIS. Expected results: This systematic review aims to comprehensively analyze the influencing factors of the stigma of nursing students towards PMI, providing a reference basis for anti-stigma intervention measures.Prospero registration number: CRD42022374419.

12.
BMC Med Educ ; 24(1): 336, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532417

RESUMO

BACKGROUND: Medical diagnostics is a pivotal bridge curriculum that receives much less attention from undergraduates in non-clinical medicine health profession programs with less student engagement and poor performance. Mind mapping is an active learning strategy for graphically presenting radiant thinking to culture clinical reasoning. The purpose of this study was to explore whether students' comprehensive diagnostic skills are enhanced through increased student engagement by employing mind mapping. METHODS: We implemented mind mapping in small-grouped workshops with 86 junior undergraduates from preventive medicine program, for physical diagnostic sessions including physical examination (PE) maneuver, electrocardiogram (ECG) interpretation and medical history collection. We also conducted assessments of the above skills, as well as online surveys regarding their expectation on this course, self-evaluation of mind mapping in teaching and the learning process of all the modules. RESULTS: Group members employing mind mapping in all PE sessions obtained higher scores in the heart and lung systems during the PE maneuver exam. Similarly, groups that made more in-depth mind maps achieved higher scores on the ECG quiz. In addition, groups displaying mind maps for history taking from normal classes and reformed class exhibited greater completeness of medical history with both standardized patients and real patients, which was consistent with increased collection of accompanying symptoms. Mind mapping was valued by the majority of students for its benefits in terms of acquiring PE maneuver, theoretical knowledge, medical history collection and medical records writing, clinical reasoning, communication skills, sense of teamwork and cooperation, professionalism and humanistic literacy. DISCUSSION: The visual feature of mind mapping evoked extensive behavioral engagement in all groups, as did cognitive and emotional engagement, as the majority of students expressed their willingness and affective reactions. In the short term, the positive feedbacks encourage growing engagement. The continuous benefits of mind mapping require long-term observation.


Assuntos
Estudantes de Medicina , Humanos , Projetos Piloto , Estudantes de Medicina/psicologia , Currículo , Aprendizagem Baseada em Problemas , Exame Físico
13.
Nat Med ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528168

RESUMO

Aging populations are susceptible to heat-related mortality because of physiological factors and comorbidities. However, the understanding of individual vulnerabilities in the aging population is incomplete. In the Chinese Longitudinal Healthy Longevity Survey, we assessed daily heatwave exposure individually for 13,527 participants (median age = 89 years) and 3,249 summer mortalities during follow-up from 2008 to 2018. The mortality risk during heatwave days according to relative temperature is approximately doubled (hazard ratio (HR) range = 1.78-1.98). We found that heatwave mortality risks were increased for individuals with functional declines in mobility (HR range = 2.32-3.20), dependency in activities of daily living (HR range = 2.22-3.27), cognitive impairment (HR = 2.22) and social isolation reflected by having nobody to ask for help during difficulties (HR range = 2.14-10.21). Contrary to current understanding, older age was not predictive of heatwave mortality risk after accounting for individual functional declines; no statistical differences were detected according to sex. Beyond age as a risk factor, our findings emphasize that functional aging is an underlying factor in enhancing heatwave resilience. Assessment of functional decline and implementing care strategies are crucial for targeted prevention of mortality during heatwaves.

14.
J Am Chem Soc ; 146(14): 9888-9896, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38546165

RESUMO

Second near-infrared (NIR-II) optical imaging technology has emerged as a powerful tool for diagnostic and image-guided surgery due to its higher imaging contrast. However, a general strategy for efficiently designing NIR-II organic molecules is still lacking, because NIR-II dyes are usually difficult to synthesize, which has impeded the rapid development of NIR-II bioprobes. Herein, based on the theoretical calculations on 62 multiaryl-pyrrole (MAP) systems with spectra ranging from the visible to the NIR-II region, a continuous red shift of the spectra toward the NIR-II region could be achieved by adjusting the type and site of substituents on the MAPs. Two descriptors (ΔEgs and µgs) were identified as exhibiting strong correlations with the maximum absorption/emission wavelengths, and the descriptors could be used to predict the emission spectrum in the NIR-II region only if ΔEgs ≤ 2.5 eV and µgs ≤ 22.55 D. The experimental absorption and emission spectra of ten MAPs fully confirmed the theoretical predictions, and biological imaging in vivo of newly designed MAP23-BBT showed high spatial resolution in the NIR-II region in deep tissue angiography. More importantly, both descriptors of ΔEgs and µgs have shown general applicability to most of the reported donor-acceptor-donor-type non-MAP NIR-II dyes. These results have broad implications for the efficient design of NIR-II dyes.

15.
Environ Pollut ; 348: 123787, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38548159

RESUMO

The co-occurrence of microplastics (MPs) and heavy metal(loid)s (HMs) has attracted growing scientific interest because of their wide distribution and environmental toxicity. Nevertheless, the interactions between MPs and HMs in soil-plant systems remain unclear. We conducted a meta-analysis with 3226 observations from 87 independent studies to quantify the impact of MPs addition on the plant biomass and HMS accumulation. Co-occurrence of MPs and HMs (except for As) induced synergistic toxicity to plant growth. MPs promoted their uptake in the shoot by 11.0% for Cd, 30.0% for Pb, and 47.1% for Cu, respectively. In contrast, MPs caused a significant decrease (22.6%, 17.9-26.9%) in the shoot As accumulation. The type and dose of MPs were correlated with the accumulation of HMs. MPs increased available concentrations of Cd, Pb, and Cu, but decreased available As concentration in soils. Meanwhile, MPs addition significantly lowered soil pH. These findings may provide explanations for MPs-mediated effects on influencing the accumulation of HMs in plants. Using a machine learning approach, we revealed that soil pH and total HMs concentration are the major contributors affecting their accumulation in shoot. Overall, our study indicated that MPs may increase the environmental risks of HMs in agroecosystems, especially metal cations.


Assuntos
Metais Pesados , Poluentes do Solo , Cádmio/análise , Microplásticos , Plásticos , Chumbo/análise , Metais Pesados/análise , Plantas , Solo , Poluentes do Solo/toxicidade , Poluentes do Solo/análise
16.
Clin Transl Med ; 14(3): e1623, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38488468

RESUMO

BACKGROUND: Alzheimer's disease (AD) and related Tauopathies are characterised by the pathologically hyperphosphorylated and aggregated microtubule-associated protein Tau, which is accompanied by neuroinflammation mediated by activated microglia. However, the role of Tau pathology in microglia activation or their causal relationship remains largely elusive. METHODS: The levels of nucleotide-binding oligomerisation domain (NOD)-like receptor pyrin domain containing 3 (NLRP3) acetylation and inflammasome activation in multiple cell models with Tau proteins treatment, transgenic mice with Tauopathy, and AD patients were measured by Western blotting and enzyme-linked immunosorbent assay. In addition, the acetyltransferase activity of Tau and NLRP3 acetylation sites were confirmed using the test-tube acetylation assay, co-immunoprecipitation, immunofluorescence (IF) staining, mass spectrometry and molecular docking. The Tau-overexpressing mouse model was established by overexpression of human Tau proteins in mouse hippocampal CA1 neurons through the adeno-associated virus injection. The cognitive functions of Tau-overexpressing mice were assessed in various behavioural tests, and microglia activation was analysed by Iba-1 IF staining and [18F]-DPA-714 positron emission tomography/computed tomography imaging. A peptide that blocks the interaction between Tau and NLRP3 was synthesised to determine the in vitro and in vivo effects of Tau-NLRP3 interaction blockade on NLRP3 acetylation, inflammasome activation, microglia activation and cognitive function. RESULTS: Excessively elevated NLRP3 acetylation and inflammasome activation were observed in 3xTg-AD mice, microtubule-associated protein Tau P301S (PS19) mice and AD patients. It was further confirmed that mimics of 'early' phosphorylated-Tau proteins which increase at the initial stage of diseases with Tauopathy, including TauT181E, TauS199E, TauT217E and TauS262E, significantly promoted Tau-K18 domain acetyltransferase activity-dependent NLRP3 acetylation and inflammasome activation in HEK293T and BV-2 microglial cells. In addition, Tau protein could directly acetylate NLRP3 at the K21, K22 and K24 sites at its PYD domain and thereby induce inflammasome activation in vitro. Overexpression of human Tau proteins in mouse hippocampal CA1 neurons resulted in impaired cognitive function, Tau transmission to microglia and microgliosis with NLRP3 acetylation and inflammasome activation. As a targeted intervention, competitive binding of a designed Tau-NLRP3-binding blocking (TNB) peptide to block the interaction of Tau protein with NLRP3 inhibited the NLRP3 acetylation and downstream inflammasome activation in microglia, thereby alleviating microglia activation and cognitive impairment in mice. CONCLUSIONS: In conclusion, our findings provide evidence for a novel role of Tau in the regulation of microglia activation through acetylating NLRP3, which has potential implications for early intervention and personalised treatment of AD and related Tauopathies.


Assuntos
Doença de Alzheimer , Inflamassomos , Humanos , Camundongos , Animais , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo , Células HEK293 , Simulação de Acoplamento Molecular , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Camundongos Transgênicos , Acetiltransferases
17.
Nucleic Acids Res ; 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38442274

RESUMO

Precise positioning of the histone-H3 variant, CENP-A, ensures centromere stability and faithful chromosomal segregation. Mislocalization of CENP-A to extra-centromeric loci results in aneuploidy and compromised cell viability associated with formation of ectopic kinetochores. The mechanism that retargets mislocalized CENP-A back to the centromere is unclarified. We show here that the downregulation of the histone H3 lysine 36 (H3K36) methyltransferase Set2 can preserve centromere localization of a temperature-sensitive mutant cnp1-1 Schizosaccharomyces pombe CENP-A (SpCENP-A) protein and reverse aneuploidy by redirecting mislocalized SpCENP-A back to centromere from ribosomal DNA (rDNA) loci, which serves as a sink for the delocalized SpCENP-A. Downregulation of set2 augments Swc2 (SWR1 complex DNA-binding module) expression and releases histone chaperone Ccp1 from the centromeric reservoir. Swc2 and Ccp1 are directed to the rDNA locus to excavate the SpCENP-Acnp1-1, which is relocalized to the centromere in a manner dependent on canonical SpCENP-A loaders, including Mis16, Mis17 and Mis18, thereby conferring cell survival and safeguarding chromosome segregation fidelity. Chromosome missegregation is a severe genetic instability event that compromises cell viability. This mechanism thus promotes CENP-A presence at the centromere to maintain genomic stability.

18.
Artigo em Inglês | MEDLINE | ID: mdl-38453766

RESUMO

People's mental health is intertwined with the social environment in which they reside. This chapter explores approaches for quantifying the area-level social environment, focusing specifically on socioeconomic deprivation and social fragmentation. We discuss census data and administrative units, egocentric and ecometric approaches, neighborhood audits, social media data, and street view-based assessments. We close the chapter by discussing possible paths forward from associations between social environments and health to establishing causality, including longitudinal research designs and time-series social environmental indices.

19.
Environ Health Perspect ; 132(3): 37001, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38427031

RESUMO

BACKGROUND: There are few studies on the health effects of long-term exposure to neighborhood greenness in a longitudinal setting, especially in Asian countries with high population densities. OBJECTIVES: This study investigates the association between long-term exposure to neighborhood greenness and hypertension among adults in Taiwan. METHODS: We selected 125,537 participants (≥18 years of age) without hypertension from Taiwan who had joined the standard medical examination program between 2001 and 2016. Neighborhood greenness was estimated using the normalized difference vegetation index (NDVI), derived from satellite images at a resolution of 250 m2. The 2-y average NDVI value within a 500-m circular buffer around participants' residences was calculated. A time-varying Cox regression model was used to investigate the association between neighborhood greenness and incident hypertension. Mediation analyses were performed to examine whether the association was explained by air pollution, leisure-time physical exercise, or body mass index (BMI). RESULTS: Compared with living in areas within the first quartile of neighborhood greenness, living in areas within the second, third, and fourth quartiles of neighborhood greenness was found to be associated with a lower risk of hypertension, with hazard ratios (HRs) and 95% confidence intervals (CIs) of 0.95 (95% CI: 0.91, 1.00), 0.95 (95% CI: 0.90, 0.99), and 0.93 (95% CI: 0.88, 0.97), respectively. Each 0.1-unit increase in the NDVI was associated with a 24% lower risk of developing hypertension (HR=0.76; 95% CI: 0.66, 0.87), with this associations being stronger among males and those with higher education levels. This association was slightly mediated by BMI but not by air pollution or leisure-time physical exercise. DISCUSSION: Our findings suggest the protective effects of neighborhood greenness on hypertension development, especially in males and well-educated individuals. Our results reinforced the importance of neighborhood greenness for supporting health. https://doi.org/10.1289/EHP13071.


Assuntos
Poluição do Ar , Hipertensão , Masculino , Adulto , Humanos , Estudos Longitudinais , Taiwan/epidemiologia , Incidência , Estudos de Coortes , Hipertensão/epidemiologia , China/epidemiologia , Material Particulado
20.
Huan Jing Ke Xue ; 45(3): 1439-1447, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471859

RESUMO

The Yangtze River, the largest river in China, has not been comprehensively studied for its basin's microplastic pollution status. Therefore, a comprehensive investigation and assessment system of microplastics was developed at the river basin scale to characterize the spatial distribution and composition of microplastics in the Yangtze River Basin in order to analyze their influencing factors and assess their ecological risks. The results showed that the microplastic abundance in the study area ranged from 21 to 44 080 n·m-3, with an average abundance of 4 483 n·m-3. The spatial distribution of microplastic abundance was higher in the tributaries than in the main streams (except the Ganjiang Basin), with the Chengdu of the Minjiang Basin being the tributary area with the highest abundance of microplastics detected. The size of microplastics in the river basin was concentrated in the 0-1 mm range; the shapes were mainly fiber and fragment; and the colors were mainly colored and transparent. Further, introducing the diversity index of microplastics, it was found that both the Simpson index and the Shannon-Wiener index could quantify the diversity of microplastic characteristic composition in the river basin, but there were certain differences in the changing trends between the two. Regression analysis showed that anthropogenic activities were significantly and positively correlated with microplastic abundance (P<0.05), and among the eight anthropogenic activity factors, civilian vehicle ownership and tourism income were the most strongly correlated with microplastic abundance, indicating that transportation and tourism were the main factors influencing microplastic distribution. From the perspective of the potential ecological risk index of microplastics, microplastics in the Yangtze River Basin posed a certain ecological risk, with 68.97% of the area falling within risk zones III and IV, with the ecological risk of microplastics in Taihu Lake warranting more widespread attention.


Assuntos
Microplásticos , Poluentes Químicos da Água , Rios , Plásticos , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , China , Medição de Risco
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