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1.
Plant Cell ; 36(5): 1892-1912, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38262703

RESUMEN

In cereal grains, starch is synthesized by the concerted actions of multiple enzymes on the surface of starch granules within the amyloplast. However, little is known about how starch-synthesizing enzymes access starch granules, especially for amylopectin biosynthesis. Here, we show that the rice (Oryza sativa) floury endosperm9 (flo9) mutant is defective in amylopectin biosynthesis, leading to grains exhibiting a floury endosperm with a hollow core. Molecular cloning revealed that FLO9 encodes a plant-specific protein homologous to Arabidopsis (Arabidopsis thaliana) LIKE EARLY STARVATION1 (LESV). Unlike Arabidopsis LESV, which is involved in starch metabolism in leaves, OsLESV is required for starch granule initiation in the endosperm. OsLESV can directly bind to starch by its C-terminal tryptophan (Trp)-rich region. Cellular and biochemical evidence suggests that OsLESV interacts with the starch-binding protein FLO6, and loss-of-function mutations of either gene impair ISOAMYLASE1 (ISA1) targeting to starch granules. Genetically, OsLESV acts synergistically with FLO6 to regulate starch biosynthesis and endosperm development. Together, our results identify OsLESV-FLO6 as a non-enzymatic molecular module responsible for ISA1 localization on starch granules, and present a target gene for use in biotechnology to control starch content and composition in rice endosperm.


Asunto(s)
Endospermo , Regulación de la Expresión Génica de las Plantas , Oryza , Proteínas de Plantas , Almidón , Oryza/genética , Oryza/metabolismo , Oryza/crecimiento & desarrollo , Endospermo/metabolismo , Endospermo/genética , Almidón/metabolismo , Almidón/biosíntesis , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Amilopectina/metabolismo , Mutación , Plantas Modificadas Genéticamente
2.
Proc Natl Acad Sci U S A ; 121(31): e2402120121, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39042680

RESUMEN

Disentangling inputs of aeolian dust, ice-rafted debris (IRD), and eroded continental detritus delivered by ocean currents to marine sediments provide important insights into Earth System processes and climate. This study uses Sr-Nd-Pb isotope ratios of the continent-derived (lithogenic) fraction in deep-sea core TN057-6 from the subantarctic Southern Ocean southwest of Africa over the past 150,000 y to identify source regions and quantify their relative contributions and fluxes utilizing a mixing model set in a Bayesian framework. The data are compared with proxies from parallel core Ocean Drilling Program Site 1090 and newly presented data from potential South America aeolian dust source areas (PSAs), allowing for an integrated investigation into atmospheric, oceanic, and cryospheric dynamics. PSA inputs varied on glacial/interglacial timescales, with southern South American sources dominating up to 88% of the lithogenic fraction (mainly Patagonia, which provided up to 68%) during cold periods, while southern African sources were more important during interglacials. During the warmer Marine Isotope Stage (MIS) 3 of the last glacial period, lithogenic fluxes were twice that of colder MIS2 and MIS4 at times, and showed unique isotope ratios best explained by Antarctic-derived IRD, likely from the Weddell Sea. The IRD intrusions contributed up to 41% at times and followed Antarctic millennial warming events that raised temperatures, causing instability of icesheet margins. High IRD was synchronous with increased bioavailable iron, nutrient utilization, high biological productivity, and decreased atmospheric CO2. Overall, TN057-6 sediments record systematic Southern Hemisphere climate shifts and cryospheric changes that impacted biogeochemical cycling on both glacial/interglacial and subglacial timescales.

3.
Proc Natl Acad Sci U S A ; 120(11): e2220563120, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36893277

RESUMEN

The transition from mafic to felsic upper continental crust (UCC) is crucial to habitability of Earth, and may be related to the onset of plate tectonics. Thus, defining when this crustal transition occurred has great significance for the evolution of Earth and its inhabitants. We demonstrate that V isotope ratios (reported as δ51V) provide insights into this transition because they correlate positively with SiO2 and negatively with MgO contents during igneous differentiation in both subduction zones and intraplate settings. Because δ51V is not affected by chemical weathering and fluid-rock interactions, δ51V of the fine-grained matrix of Archean to Paleozoic (3 to 0.3 Ga) glacial diamictite composites, which sample the UCC at the time of glaciation, reflect the chemical composition of the UCC through time. The δ51V values of glacial diamictites systematically increase with time, indicating a dominantly mafic UCC at ~3 Ga; the UCC was dominated by felsic rocks only after 3 Ga, coinciding with widespread continental emergence and many independent estimates for the onset of plate tectonics.

4.
Plant Physiol ; 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39218791

RESUMEN

Flower drop is a major cause for yield loss in many crops. Previously, we found that tomato (Solanum lycopersicum) INFLORESCENCE DEFICIENT IN ABSCISSION-Like (SlIDL6) contributes to flower drop induced by low light. However, the molecular mechanisms by which SlIDL6 acts as a signal to regulate low light-induced abscission remain unclear. In this study, SlIDL6 was found to elevate cytosolic Ca2+ concentrations ([Ca2+]cyt) in the abscission zone (AZ), which was required for SlIDL6-induced flower drop under low light. We further identified that one calcium-dependent protein kinase gene (SlCPK10) was highly expressed in the AZ and up-regulated by SlIDL6-triggered [Ca2+]cyt. Over-expression and knockout of SlCPK10 in tomato resulted in accelerated and delayed abscission, respectively. Genetic evidence further indicated that knockout of SlCPK10 significantly impaired the function of SlIDL6 in accelerating abscission. Furthermore, Ser-371 phosphorylation in SlCPK10 dependent on SlIDL6 was necessary and sufficient for its function in regulating flower drop, probably by stabilizing the SlCPK10 proteins. Taken together, our findings reveal that SlCPK10, as a downstream component of the IDL6 signaling pathway, regulates flower drop in tomato under low light stress.

5.
Ann Neurol ; 95(5): 917-928, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38356322

RESUMEN

OBJECTIVE: Triggering receptor expressed on myeloid cells-2 (TREM2) and progranulin (PGRN) are critical regulators of microglia activation and can be detected in cerebrospinal fluid (CSF). However, whether microglial reactivity is detrimental or neuroprotective for Alzheimer disease (AD) is still debatable. METHODS: We identified 663 participants with baseline ß-amyloid (Aß) positron emission tomography (PET) and CSF biomarker data, including phosphorylated tau181 (p-Tau181), soluble TREM2 (sTREM2), PGRN, and growth-associated protein-43 (GAP-43). Among them, 254 participants had concurrent longitudinal CSF biomarkers. We used multivariate regression analysis to study the associations of CSF microglial biomarkers with Aß PET, CSF p-Tau181, and CSF GAP-43 cross-sectionally and longitudinally. A Chinese aging cohort's independent CSF samples (n = 65) were analyzed as a validation. RESULTS: Higher baseline levels of CSF microglial biomarkers were related to faster rates of CSF sTREM2 increase and CSF PGRN decrease. Elevated CSF p-Tau181 was associated with higher levels of CSF microglial biomarkers and faster rates of CSF sTREM2 increase and CSF PGRN decrease. In both cohorts, higher Aß burden was associated with attenuated CSF p-Tau181 effects on CSF microglial biomarker increases. Independent of Aß PET and CSF p-Tau181 pathologies, higher levels of CSF sTREM2 but not CSF PGRN were related to elevated CSF GAP-43 levels and faster rates of CSF GAP-43 increase. INTERPRETATION: These findings suggest that higher Aß burden may attenuate the p-Tau-associated microglial responses, and TREM2-related microglial reactivity may independently correlate with GAP-43-related presynaptic loss. This study highlights the two-edged role of microglial reactivity in AD and other neurodegenerative diseases. ANN NEUROL 2024;95:917-928.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Glicoproteínas de Membrana , Microglía , Tomografía de Emisión de Positrones , Progranulinas , Receptores Inmunológicos , Proteínas tau , Humanos , Microglía/metabolismo , Masculino , Femenino , Péptidos beta-Amiloides/líquido cefalorraquídeo , Péptidos beta-Amiloides/metabolismo , Anciano , Proteínas tau/líquido cefalorraquídeo , Enfermedad de Alzheimer/líquido cefalorraquídeo , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/diagnóstico por imagen , Persona de Mediana Edad , Receptores Inmunológicos/metabolismo , Progranulinas/líquido cefalorraquídeo , Glicoproteínas de Membrana/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Anciano de 80 o más Años , Estudios Longitudinales , Estudios Transversales
6.
J Comput Chem ; 45(24): 2080-2090, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38742401

RESUMEN

We show herein that 1,10-dicyano substitution restricts the paragon fluxionality of bullvalene to just 14 isomers which isomerize along a single cycle. The restricted fluxionality of 1,10-dicyanobullvalene (DCB) is investigated by means of: (i) Bonding analyses of the isomer structures using the adaptive natural density partitioning (AdNDP). (ii) Quantum dynamical simulations of the isomerizations along the cyclic intrinsic reaction coordinate of the potential energy surface (PES). The PES possesses 14 equivalent potential wells supporting 14 isomers which are separated by 14 equivalent potential barriers supporting 14 transition states. Accordingly, at low temperatures, DCB appears as a hindered molecular rotor, without any delocalization of the wavefunction in the 14 potential wells, without any nuclear spin isomers, and with completely negligible tunneling. These results are compared and found to differ from those for molecular boron rotors. (iii) Born-Oppenheimer molecular dynamics (BOMD) simulations of thermally activated isomerizations. (iv) Calculations of the rate constants in the frame of transition state theory (TST) with reasonable agreement achieved with the BOMD results. (v) Simulations of the equilibration dynamics using rate equations for the isomerizations with TST rate coefficients. Accordingly, in the long-time limit, isomerizations of the 14 isomers, each with Cs symmetry, approach the "14 Cs → C7v" thermally averaged structure. This is a superposition of the 14 equally populated isomer structures with an overall C7v symmetry. By extrapolation, the results for DCB yield working hypotheses for so far un-explored properties e.g. for the equilibration dynamics of C10H10.

7.
BMC Med ; 22(1): 56, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38317226

RESUMEN

BACKGROUND: A comprehensive overview of artificial intelligence (AI) for cardiovascular disease (CVD) prediction and a screening tool of AI models (AI-Ms) for independent external validation are lacking. This systematic review aims to identify, describe, and appraise AI-Ms of CVD prediction in the general and special populations and develop a new independent validation score (IVS) for AI-Ms replicability evaluation. METHODS: PubMed, Web of Science, Embase, and IEEE library were searched up to July 2021. Data extraction and analysis were performed for the populations, distribution, predictors, algorithms, etc. The risk of bias was evaluated with the prediction risk of bias assessment tool (PROBAST). Subsequently, we designed IVS for model replicability evaluation with five steps in five items, including transparency of algorithms, performance of models, feasibility of reproduction, risk of reproduction, and clinical implication, respectively. The review is registered in PROSPERO (No. CRD42021271789). RESULTS: In 20,887 screened references, 79 articles (82.5% in 2017-2021) were included, which contained 114 datasets (67 in Europe and North America, but 0 in Africa). We identified 486 AI-Ms, of which the majority were in development (n = 380), but none of them had undergone independent external validation. A total of 66 idiographic algorithms were found; however, 36.4% were used only once and only 39.4% over three times. A large number of different predictors (range 5-52,000, median 21) and large-span sample size (range 80-3,660,000, median 4466) were observed. All models were at high risk of bias according to PROBAST, primarily due to the incorrect use of statistical methods. IVS analysis confirmed only 10 models as "recommended"; however, 281 and 187 were "not recommended" and "warning," respectively. CONCLUSION: AI has led the digital revolution in the field of CVD prediction, but is still in the early stage of development as the defects of research design, report, and evaluation systems. The IVS we developed may contribute to independent external validation and the development of this field.


Asunto(s)
Inteligencia Artificial , Enfermedades Cardiovasculares , Humanos , Enfermedades Cardiovasculares/diagnóstico , Medición de Riesgo/métodos , Tamizaje Masivo/métodos , Reproducibilidad de los Resultados
8.
Small ; 20(13): e2308165, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37968247

RESUMEN

During the layer-by-layer (LBL) processing of polymer solar cells (PSCs), the swelling and molecule interdiffusion are essential for achieving precise, controllable vertical morphology, and thus efficient PSCs. However, the influencing mechanism of material properties on morphology and correlated device performance has not been paid much attention. Herein, a series of fluorinated/non-fluorinated polymer donors (PBDB-T and PBDB-TF) and non-fullerene acceptors (ITIC, IT-2F, and IT-4F) are employed to investigate the performance of LBL devices. The impacts of fluorine substitution on the repulsion and miscibility between the donor and acceptor, as well as the molecular arrangement of the donor/acceptor and the vertical distribution of the LBL devices are systematically explored by the measurement of donor/acceptor Flory-Huggins interaction parameters, spectroscopic ellipsometry, and neutron reflectivity, respectively. With efficient charge transfer due to the ideal vertical and horizon morphology properties, devices based on PBDB-TF/IT-4F exhibit the highest fill factors (FFs) as well as champion power conversion efficiencies (PCEs). With this guidance, high-performance LBL devices with PCE of 17.2%, 18.5%, and 19.1% are obtained by the fluorinated blend of PBDB-TF/Y6, PBDB-TF/L8-BO, and D18/L8-BO respectively.

9.
Plant Biotechnol J ; 2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39180364

RESUMEN

Starch is synthesized as insoluble, semicrystalline particles within plant chloroplast and amyloplast, which are referred to as starch grains (SGs). The size and morphology of SGs in the cereal endosperm are diverse and species-specific, representing a key determinant of the suitability of starch for industrial applications. However, the molecular mechanisms modulating SG size in cereal endosperm remain elusive. Here, we functionally characterized the rice (Oryza sativa) mutant substandard starch grain7 (ssg7), which exhibits enlarged SGs and defective endosperm development. SSG7 encodes a plant-specific DUF1001 domain-containing protein homologous to Arabidopsis (Arabidopsis thaliana) CRUMPLED LEAF (AtCRL). SSG7 localizes to the amyloplast membrane in developing endosperm. Several lines of evidence suggest that SSG7 functions together with SSG4 and SSG6, known as two regulators essential for SG development, to control SG size, by interacting with translocon-associated components, which unveils a molecular link between SG development and protein import. Genetically, SSG7 acts synergistically with SSG4 and appears to be functional redundancy with SSG6 in modulating SG size and endosperm development. Collectively, our findings uncover a multimeric functional protein complex involved in SG development in rice. SSG7 represents a promising target gene for the biotechnological modification of SG size, particularly for breeding programs aimed at improving starch quality.

10.
Artículo en Inglés | MEDLINE | ID: mdl-38976036

RESUMEN

PURPOSE: [18F]-D3FSP is a new ß-amyloid (Aß) PET imaging tracer designed to decrease nonspecific signals in the brain by reducing the formation of the N-demethylated product. However, its optimal reference region for calculating the standardized uptake value ratio (SUVR) and its relation to the well-established biomarkers of Alzheimer's disease (AD) are still unclear. METHODS: We recruited 203 participants from the Greater Bay Area Healthy Aging Brain Study (GHABS) to undergo [18F]-D3FSP Aß PET imaging. We analyzed plasma Aß42/Aß40, p-Tau181, glial fibrillary acidic protein (GFAP), and neurofilament light (NfL) using the Simoa platform. We compared the standardized uptake value (SUV) of five reference regions (cerebellum, cerebellum cortex, brainstem/PONs, white matter, composite of the four regions above) and AD typical cortical region (COMPOSITE) SUVR among different clinical groups. The association of D3FSP SUVR with plasma biomarkers, imaging biomarkers, and cognition was also investigated. RESULTS: Brainstem/PONs SUV showed the lowest fluctuation across diagnostic groups, and COMPOSITE D3FSP SUVR had an enormous effect distinguishing cognitively impaired (CI) individuals from cognitively unimpaired (CU) individuals. COMPOSITE SUVR (Referred to brainstem/PONs) was positively correlated with p-Tau181 (p < 0.001), GFAP (p < 0.001), NfL (p = 0.014) in plasma and temporal-metaROI tau deposition (p < 0.001), and negatively related to plasma Aß42/Aß40 (p < 0.001), temporal-metaROI cortical thickness (p < 0.01), residual hippocampal volume (p < 0.001) and cognition (p < 0.001). The voxel-wise analysis replicated these findings. CONCLUSION: This study suggests brainstem/PONs as an optimal reference region for calculating D3FSP SUVR to quantify cortical Aß plaques in the brain. [18F]-D3FSP could distinguish CI from CU and strongly correlates with well-established plasma biomarkers, tau PET, neurodegeneration, and cognitive decline. However, future head-to-head comparisons of [18F]-D3FSP PET images with other validated Aß PET tracers or postmortem results are crucial.

11.
Cell Commun Signal ; 22(1): 268, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38745207

RESUMEN

Ulcerative colitis (UC) is increasingly common, and it is gradually become a kind of global epidemic. UC is a type of inflammatory bowel disease (IBD), and it is a lifetime recurrent disease. UC as a common disease has become a financial burden for many people and has the potential to develop into cancer if not prevented or treated. There are multiple factors such as genetic factors, host immune system disorders, and environmental factors to cause UC. A growing body of research have suggested that intestinal microbiota as an environmental factor play an important role in the occurrence and development of UC. Meanwhile, evidence to date suggests that manipulating the gut microbiome may represent effective treatment for the prevention or management of UC. In addition, the main clinical drugs to treat UC are amino salicylate and corticosteroid. These clinical drugs always have some side effects and low success rate when treating patients with UC. Therefore, there is an urgent need for safe and efficient methods to treat UC. Based on this, probiotics and prebiotics may be a valuable treatment for UC. In order to promote the wide clinical application of probiotics and prebiotics in the treatment of UC. This review aims to summarize the recent literature as an aid to better understanding how the probiotics and prebiotics contributes to UC while evaluating and prospecting the therapeutic effect of the probiotics and prebiotics in the treatment of UC based on previous publications.


Asunto(s)
Colitis Ulcerosa , Microbioma Gastrointestinal , Prebióticos , Probióticos , Humanos , Colitis Ulcerosa/terapia , Colitis Ulcerosa/microbiología , Probióticos/uso terapéutico , Probióticos/administración & dosificación , Prebióticos/administración & dosificación , Animales
12.
BMC Vet Res ; 20(1): 40, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38297289

RESUMEN

BACKGROUND: mcr-1-positive Escherichia coli has emerged as a significant threat to human health, veterinary health, and food safety in recent years. After the prohibition of colistin as a feed additive in animal husbandry in China, a noticeable reduction in both colistin resistance and the prevalence of mcr-1 was observed in E. coli from animals and humans. OBJECTIVES: To assess the prevalence of the colistin resistance gene mcr-1 and characterize its genetic context in E. coli strains derived from fecal and meat samples from food-producing animals in China. METHODS: A total of 1,353 fecal samples and 836 food samples were collected between 2019 and 2020 in China. E. coli isolates were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and their susceptibility to colistin were determined using the broth microdilution method. The colistin-resistant E. coli isolates were screened for the presence of mcr by PCR analysis and sequencing. The minimal inhibitory concentrations (MICs) of 15 antimicrobial agents against the mcr-1-positive strains were further tested using the agar dilution method, conjugation assays were performed, and whole genome sequencing was performed using Illumina HiSeq. RESULTS: In total, 1,403 E. coli strains were isolated. Thirteen isolates from chicken meat (n = 7), chickens (n = 3), and pigs (n = 3) were resistant to colistin with MIC values of 4 to 16 mg/L, and carried mcr-1. All mcr-1-positive strains, except for isolate AH20PE105, contained multiple resistance genes and exhibited multidrug-resistant phenotypes. They belonged to 10 sequence types (STs), including a novel ST (ST14521). mcr-1 was located on IncI2 (n = 9), IncX4 (n = 2), and IncHI2 (n = 2) plasmids, which were highly similar to other mcr-1-carrying plasmids sharing the same incompatibility type. Seven mcr-1-carrying plasmids could be successfully conjugally transferred to E. coli C600. CONCLUSIONS: While the low prevalence of mcr-1 (0.93%) identified in this study may not immediately seem alarming, the very emergence of this gene merits attention given its implications for colistin resistance and public health. Hence, ongoing surveillance of mcr-1 in E. coli remains crucial.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Animales , Humanos , Porcinos , Colistina/farmacología , Proteínas de Escherichia coli/genética , Antibacterianos/farmacología , Prevalencia , Pollos/genética , Plásmidos , China/epidemiología , Pruebas de Sensibilidad Microbiana/veterinaria , Farmacorresistencia Bacteriana/genética
13.
BMC Public Health ; 24(1): 2329, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39192237

RESUMEN

OBJECTIVE: The purpose of this study was to translate and validate the reliability and validity of the Falls Health Literacy Scale (FHLS). METHODS: A total of 509 elderly hospitalized patients were recruited from Wuhan, China. The reliability of the scale was validated using internal consistency, split-half reliability and retest reliability. The validity of the scale with content validity index, exploratory factor analysis and validation factor analysis. RESULTS: The Chinese version of the FHLS consists of 3 dimensions, falls prevention experience, general health and staying active, and seeking health advice and services, with a total of 25 entries. The Cronbach's α coefficient of the scale was 0.949, the range of Cronbach's α values for each dimension was 0.911 to 0.927, the split-half reliability was 0.800, and the retest reliability was 0.801. The I-CVI of the scale ranged from 0.833 to 1.000, and the S-CVI was 0.973. The KMO value was 0.925, and the χ2 value of Bartlett's sphericity test was 5,784.223 (P < 0.001). Exploratory factor analysis extracted four metric factors, which were discussed and combined into three metric factors explaining 56.361% of the total variance. The results of validation factor analysis showed that the model indicators were: χ2/df = 2.182, CFI = 0.928, GFI = 0.820, NFI = 0.875, IFI = 0.928, RFI = 0.862, TLI = 0.920, RMSEA = 0.076, MRM = 0.021, which met the criteria, and the model fitting of the indicators were all in good. CONCLUSIONS: The Chinese version of the FHLS has good reliability and validity for elderly patients and is suitable for assessing the falls health literacy level of elderly patients. The assessment of fall health literacy in elderly patients can help healthcare professionals to provide individualized health education to them, so as to improve the awareness of fall prevention in elderly patients.


Asunto(s)
Accidentes por Caídas , Alfabetización en Salud , Traducciones , Humanos , Alfabetización en Salud/estadística & datos numéricos , Accidentes por Caídas/prevención & control , Femenino , Masculino , Anciano , China , Reproducibilidad de los Resultados , Psicometría , Encuestas y Cuestionarios/normas , Análisis Factorial , Anciano de 80 o más Años , Traducción , Persona de Mediana Edad
14.
J Med Internet Res ; 26: e47645, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-38869157

RESUMEN

In recent years, there has been explosive development in artificial intelligence (AI), which has been widely applied in the health care field. As a typical AI technology, machine learning models have emerged with great potential in predicting cardiovascular diseases by leveraging large amounts of medical data for training and optimization, which are expected to play a crucial role in reducing the incidence and mortality rates of cardiovascular diseases. Although the field has become a research hot spot, there are still many pitfalls that researchers need to pay close attention to. These pitfalls may affect the predictive performance, credibility, reliability, and reproducibility of the studied models, ultimately reducing the value of the research and affecting the prospects for clinical application. Therefore, identifying and avoiding these pitfalls is a crucial task before implementing the research. However, there is currently a lack of a comprehensive summary on this topic. This viewpoint aims to analyze the existing problems in terms of data quality, data set characteristics, model design, and statistical methods, as well as clinical implications, and provide possible solutions to these problems, such as gathering objective data, improving training, repeating measurements, increasing sample size, preventing overfitting using statistical methods, using specific AI algorithms to address targeted issues, standardizing outcomes and evaluation criteria, and enhancing fairness and replicability, with the goal of offering reference and assistance to researchers, algorithm developers, policy makers, and clinical practitioners.


Asunto(s)
Enfermedades Cardiovasculares , Aprendizaje Automático , Humanos , Reproducibilidad de los Resultados , Algoritmos
15.
Ecotoxicol Environ Saf ; 284: 116927, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39216334

RESUMEN

Compound pollution at industrial sites impedes urban development, especially when there is a lack of understanding about the spatial variations of internal pollution in industrial areas producing light-weight materials. In this study, spatial distribution and ecological risks of potentially toxic elements (PTEs), volatile organic compounds (VOCs), and petroleum hydrocarbons (C10-40) in the soil and groundwater of an Al/Cu (aluminum/copper) industrial site have been analyzed comprehensively. Results revealed the progressive clustering of pollutants in different soil layers, which indicated varying levels of penetration and migration of pollutants from the surface downward. Furthermore, severity of pollution varied according to pollutant type, with Cu (5-10,228 mg kg-1) often exceeding the background levels significantly (>40). Cd (0.03-2.60 mg kg-1) and Hg (0.01-3.73 mg kg-1) were found at elevated concentrations in deeper soil layers, suggesting distinct variations of PTEs across different soil depths. Among the more hazardous VOCS, polychlorinated biphenyls (1.80-234 µg kg-1) were particularly prevalent in the deeper layers of soil. Petroleum hydrocarbons (C10-40) were widely detected (6-582 mg kg-1), showing significant migration potential from surface to deep soil. These findings suggest that prolonged industrial activities lead to deep-seated accumulation of pollutants, which also impacts the groundwater, contributing to long-term dispersion of contaminants. Furthermore, multivariate statistical analysis indicated certain positive correlations among the distribution of Cu, Pb and petroleum hydrocarbons, indicating possible coupling of these pollutants. Severe Cu pollution caused an ecological risk in the surface soil layer (covering >20 % area of high pollution site, contributing >40 % ecological risk). While the Hg and Cd posed significant risks in the deeper soil layers, showing higher risk coefficients and mobility. The study provides crucial insights into the transformation of urban areas with a history of industrial uses into community spaces and highlights the risks posed by the remaining pollutants.

16.
Alzheimers Dement ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38982860

RESUMEN

BACKGROUND: Previous studies have found that Alzheimer's disease (AD)-related plasma markers are associated with amyloid beta (Aß) deposition, but the change of this association in different Aß pathological stages remains unclear. METHODS: Data were obtained from the SILCODE. According to the standardized uptake value ratio (SUVR) and Aß stage classification, correlation analysis was performed among plasma biomarkers, and voxel/SUVR values in the regions of interest (ROI) and clinical scale information, respectively. Mediation analysis was used to study the possible pathways. RESULTS: The proportion of cognitively normal (CN) and subjective cognitive decline (SCD) was the highest in stages A0 to 1, while in stages A2 to 4, the proportion of mild cognitive impairment (MCI) and AD increased. Plasma phosphorylated tau (p-tau)181 and glial fibrillary acidic protein (GFAP) levels were significantly lower in stage A0 compared to the later phases. Two pathways demonstrated fully mediated effects: positron emission tomography (PET) SUVR-plasma p-tau181-Mini-Mental State Examination (MMSE) and PET SUVR-plasma GFAP-MMSE. DISCUSSION: This study demonstrated the role of plasma biomarkers in the early stage of AD, especially in SCD, from both the clinical diagnosis and Aß stage dimensions. HIGHLIGHTS: Plasma ptau181 and GFAP level serve as indicators of early Alzheimer's disease and the pathologic Aß staging classification. A possible ceiling effect of GFAP was observed in the mid-to-late stages of the AD course. This study confirms the role of AD plasma markers in promoting Aß deposition at an early stage, particularly in females with subjective cognitive decline(SCD). The overlapping brain regions of plasma p-tau181, GFAP, and neurofilament light for Aß deposition in the brain in early AD were distributed across various regions, including the posterior cingulate gyrus, rectus gyrus, and inferior temporal gyrus.

17.
Alzheimers Dement ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39132849

RESUMEN

INTRODUCTION: The spatial and temporal patterns of cortical mean diffusivity (cMD), as well as its association with Alzheimer's disease (AD) and suspected non-Alzheimer's pathophysiology (SNAP), are not yet fully understood. METHODS: We compared baseline (n = 617) and longitudinal changes (n = 421) of cMD, cortical thickness, and gray matter volume and their relations to vascular risk factors, amyloid beta (Aß), and tau positron emission tomography (PET), and longitudinal cognitive decline in Aß PET negative and positive older adults. RESULTS: cMD increases were more sensitive to detecting brain structural alterations than cortical thinning and gray matter atrophy. Tau-related cMD increases partially mediated Aß-related cognitive decline in AD, whereas vascular disease-related increased cMD levels substantially mediated age-related cognitive decline in SNAP. DISCUSSION: These findings revealed the dynamic changes of microstructural and macrostructural indicators and their associations with AD and SNAP, providing novel insights into understanding upstream and downstream events of cMD in neurodegenerative disease. HIGHLIGHTS: Cortical mean diffusivity (cMD) was more sensitive to detecting structural changes than macrostructural factors. Tau-related cMD increases partially mediated amyloid beta-related cognitive decline in Alzheimer's disease (AD). White matter hyperintensity-related higher cMD mainly explained the age-related cognitive decline in suspected non-Alzheimer's pathophysiology (SNAP). cMD may assist in tracking earlier neurodegenerative signs in AD and SNAP.

18.
Alzheimers Dement ; 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39072956

RESUMEN

INTRODUCTION: Subjective cognitive decline (SCD) in amyloid-positive (Aß+) individuals was proposed as a clinical indicator of Stage 2 in the Alzheimer's disease (AD) continuum, but this requires further validation across cultures, measures, and recruitment strategies. METHODS: Eight hundred twenty-one participants from SILCODE and DELCODE cohorts, including normal controls (NC) and individuals with SCD recruited from the community or from memory clinics, underwent neuropsychological assessments over up to 6 years. Amyloid positivity was derived from positron emission tomography or plasma biomarkers. Global cognitive change was analyzed using linear mixed-effects models. RESULTS: In the combined and stratified cohorts, Aß+ participants with SCD showed steeper cognitive decline or diminished practice effects compared with NC or Aß- participants with SCD. These findings were confirmed using different operationalizations of SCD and amyloid positivity, and across different SCD recruitment settings. DISCUSSION: Aß+ individuals with SCD in German and Chinese populations showed greater global cognitive decline and could be targeted for interventional trials. HIGHLIGHTS: SCD in amyloid-positive (Aß+) participants predicts a steeper cognitive decline. This finding does not rely on specific SCD or amyloid operationalization. This finding is not specific to SCD patients recruited from memory clinics. This finding is valid in both German and Chinese populations. Aß+ older adults with SCD could be a target population for interventional trials.

19.
Molecules ; 29(16)2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39202910

RESUMEN

Among the known planar pentacoordinate atoms, chlorine is missing due to its large radius and high electronegativity. Herein, we report the first star-like superhalogen anion D5h Cl©Li5Cl5- (1), which contains a planar pentacoordinate chlorine (ppCl) at the center. Computer structural searches and high-level calculations reveal that 1 is a true global minimum (GM) on the potential energy surfaces. Molecular dynamics simulations indicate it is kinetically stable against isomerization or decomposition. Although detailed chemical bonding analyses reveal one delocalized 6c-2e σ bond over the Cl©Li5 central unit and five delocalized 3c-2e σ bonds along the periphery, while aromaticity has very little beneficial effect on stability, instead, ionic interaction dominates the stability of the system. More encouragingly, with the large HOMO-LUMO energy gap of 7.66 eV and vertical detachment energy of 7.87 eV, the highly chemically inert 1 can be viewed as a typical superhalogen anion and is possible to be synthesized and characterized in future experiments.

20.
BMC Nurs ; 23(1): 62, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38254125

RESUMEN

BACKGROUND: The organizational climate that fosters and supports the implementation of evidence is a key factor influencing the effective implementation of evidence-based practice (EBP). Nurses, being the largest group of medical staff, play a crucial role in EBP implementation. The perception of the climate for EBP implementation among nurses in their organizations is unknown, especially among Chinese nurses. AIMS: To clarify the implementation climate of EBP among Chinese nurses and identify the factors associated with the implementation and development of evidence-based nursing practices. METHODS: This study employed a descriptive cross-sectional study design. From March 2023 to April 2023, a sample of nurses (n = 1260) from two Tertiary care hospitals in central China were selected and surveyed by self-designed social-demographic questionnaire and Implementation Climate Scale. Multiple linear stepwise regression analysis was conducted to determine the predictors of implementation climate. RESULTS: The nurses achieved a mean ICS score of 59.10 ± 11.22, with mean scores exceeding 3 points for each sub-dimension and item. In the results of multiple linear regression, income satisfaction, implementation of evidence-based nursing practice project(s) within the unit, experience of evidence-based nursing practice during working life, and specific training or courses in evidence-based nursing practice were predictors of ICS. Of these, income satisfaction was the most significant predictor. These factors could explain 17.5% of the total variance in implementation climate. CONCLUSION: The climate for implementing EBP in Chinese nursing organizations was relatively strong. Nursing managers can enhance the climate for implementing EBP in their organizations by actively improving salary and enhancing EBP-related trainings and practices. RELEVANCE TO CLINICAL PRACTICE: Understanding nurses' perceptions of the EBP implementation climate in their organizations can help to identify specific barriers and facilitators to the development of EBP and facilitate its successful implementation. PATIENT OR PUBLIC CONTRIBUTION: Clinical nurses were involved in data collection and completed the questionnaires on EBP implementation climate.

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