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1.
Small ; 20(9): e2308273, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37849032

RESUMEN

Aqueous zinc-ion batteries (AZIBs) face challenges in achieving high energy density compared to conventional lithium-ion batteries (LIBs). The lower operating voltage and excessive Zn metal as anode pose constraints on the overall energy storage capacity of these batteries. An effective approach is to reduce the thickness of the Zn metal anode and control its mass appropriately. However, under the condition of using a thin Zn anode, the performance of AZIBs is often unsatisfactory. Through experiments and computational simulations, the electrode structural change and the formation of dead Zn as the primary reasons for the failure of batteries under a high Zn utilization rate are identified. Based on this understanding, a universal synergistic strategy that combines Cu foil current collectors and electrolyte additives to maintain the structural and thermodynamic stability of the Zn anode under a high Zn utilization rate (ZUR) is proposed. Specifically, the Cu current collectors can ensure that the Zn anode structure remains intact based on the spontaneous filling effect, while the additives can suppress parasitic side reactions at the interface. Ultimately, the symmetric cell demonstrates a cycling duration of 900 h at a 70% ZU, confirming the effectiveness of this strategy.

2.
Glob Chang Biol ; 30(2): e17182, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38348761

RESUMEN

Biodiversity is considered important to the mitigation of global change impacts on ecosystem multifunctionality in terrestrial ecosystems. However, potential mechanisms through which biodiversity maintains ecosystem multifunctionality under global change remain unclear. We grew 132 plant communities with two levels of plant diversity, crossed with treatments based on 10 global change factors (nitrogen deposition, soil salinity, drought, plant invasion, simulated grazing, oil pollution, plastics pollution, antibiotics pollution, heavy metal pollution, and pesticide pollution). All global change factors negatively impacted ecosystem multifunctionality, but negative impacts were stronger in high compared with low diversity plant communities. We explored potential mechanisms for this unexpected result, finding that the inhibition of selection effects (i.e., selection for plant species associated with high ecosystem functioning) contributed to sensitivity of ecosystem multifunctionality to global change. Specifically, global change factors decreased the abundance of novel functional plants (i.e., legumes) in high but not low diversity plant communities. The negative impacts of global change on ecosystem multifunctionality were also mediated by increased relative abundance of fungal plant pathogens (identified from metabarcoding of soil samples) and their negative relationship with the abundance of novel functional plants. Taken together, our experiment highlights the importance of protecting high diversity plant communities and legumes, and managing fungal pathogens, to the maintenance of ecosystem multifunctionality in the face of complex global change.


Asunto(s)
Ecosistema , Fabaceae , Biodiversidad , Plantas , Suelo , Contaminación Ambiental
3.
Anal Chem ; 95(12): 5275-5284, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36898021

RESUMEN

Owing to its high throughput, simplicity, and rapidity, enzyme-linked immunosorbent assay (ELISA) has attracted much attention in the field of immunoassays. However, the traditional ELISA usually affords a single signal readout and the labeling ability of the enzyme used is poor, resulting in low accuracy and a limited detection range. Herein, a vanadium nanospheres (VNSs)-mediated competitive ratio nanozymes-linked immunosorbent assay (VNSs-RNLISA) was created for the sensitive detection of the T-2 toxin (T-2). As the key to the biosensor, the VNSs with superoxide dismutase-like and peroxidase-like dual-enzyme mimetic activities were synthesized by a one-step hydrothermal method, which oxidized 1,1-diphenyl-2-picryl-hydrazyl fading and catalyzed 3,3',5,5'-tetramethylbenzidine (TMB) color development. Therefore, T-2 could not only be qualitatively measured with the naked eye but also be quantitatively evaluated by monitoring the ratio of absorbance at 450 and 517 nm wavelengths. Moreover, the characterization of a VNSs-labeled antibody probe showed strong dual-enzymatic activity, excellent stability, and high affinity with T-2 [the affinity constant (ka) was approximately 1.36 × 108 M-1], which can significantly improve the detection sensitivity. The limit of detection of VNSs-RNLISA was 0.021 ng/mL, which was approximately 27-fold more sensitive than the single signal nanozymes-linked immunosorbent assay (0.561 ng/mL). Besides, the change in the ratio of absorbance (Δ450/Δ517) decreased linearly in a range of 0.22-13.17 ng/mL, outperforming the detection range of a single-mode nano-enzyme-linked immunosorbent assay using TMB by a factor of 1.6 times. Furthermore, the VNSs-RNLISA was successfully used to identify T-2 in maize and oat samples, with recoveries ranging from 84.216 to 125.371%. Overall, this tactic offered a promising platform for the quick detection of T-2 in food and might broaden the application range of the enzyme-linked immunosorbent assay.


Asunto(s)
Técnicas Biosensibles , Nanosferas , Toxina T-2 , Inmunoensayo/métodos , Vanadio , Inmunoadsorbentes , Límite de Detección
4.
Small ; 19(43): e2303303, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37376812

RESUMEN

Designing definite transition metal heterointerfaces is considered an effective strategy for the construction of efficient and robust oxygen evolution reaction (OER) electrocatalysts, but rather challenging. Herein, amorphous NiFe hydr(oxy)oxide nanosheet arrays (A-NiFe HNSAs) are grown in situ on the surface of a self-supporting Ni metal-organic frameworks (SNMs) electrode via a combination strategy of ion exchange and hydrolytic co-deposition for efficient and stable large-current-density water oxidation. The existence of the abundant metal-oxygen bonds on the heterointerfaces can not only be of great significance to alter the electronic structure and accelerate the reaction kinetics, but also enable the redistribution of Ni/Fe charge density to effectively control the adsorption behavior of important intermediates with a close to the optimal d-band center, dramatically narrowing the energy barriers of the OER rate-limiting steps. By optimizing the electrode structure, the A-NiFe HNSAs/SNMs-NF exhibits outstanding OER performance with small overpotentials of 223 and 251 mV at 100 and 500 mA cm-2 , a low Tafel slope of 36.3 mV dec-1 , and excellent durability during 120 h at 10 mA cm-2 . This work significantly provides an avenue to understand and realize rationally designed heterointerface structures toward effective oxygen evolution in water-splitting applications.

5.
Biomed Eng Online ; 22(1): 80, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37582824

RESUMEN

BACKGROUND: Cerebral edema is an extremely common secondary disease in post-stroke. Point-of-care testing for cerebral edema types has important clinical significance for the precise management to prevent poor prognosis. Nevertheless, there has not been a fully accepted bedside testing method for that. METHODS: A symmetric cancellation near-field coupling phase shift (NFCPS) monitoring system is established based on the symmetry of the left and right hemispheres and the fact that unilateral lesions do not affect healthy hemispheres. For exploring the feasibility of this system to reflect the occurrence and development of cerebral edema, 13 rabbits divided into experimental group (n = 8) and control group (n = 5) were performed 24-h NFCPS continuous monitoring experiments. After time difference offset and feature band averaging processing, the changing trend of NFCPS at the stages dominated by cytotoxic edema (CE) and vasogenic edema (VE), respectively, was analyzed. Furthermore, the features under the different time windows were extracted. Then, a discriminative model of cerebral edema types based on support vector machines (SVM) was established and performance of multiple feature combinations was compared. RESULTS: The NFCPS monitoring outcomes of experimental group endured focal ischemia modeling by thrombin injection show a trend of first decreasing and then increasing, reaching the lowest value of - 35.05° at the 6th hour. Those of control group do not display obvious upward or downward trend and only fluctuate around the initial value with an average change of - 0.12°. Furthermore, four features under the 1-h and 2-h time windows were extracted. Based on the discriminative model of cerebral edema types, the classification accuracy of 1-h window is higher than 90% and the specificity is close to 1, which is almost the same as the performance of the 2-h window. CONCLUSION: This study proves the feasibility of NFCPS technology combined with SVM to distinguish cerebral edema types in a short time, which is promised to become a new solution for immediate and precise management of dehydration therapy after ischemic stroke.


Asunto(s)
Edema Encefálico , Accidente Cerebrovascular , Animales , Conejos , Edema Encefálico/tratamiento farmacológico , Máquina de Vectores de Soporte , Pruebas en el Punto de Atención
6.
Ecotoxicol Environ Saf ; 259: 115029, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37216867

RESUMEN

Nitrogen (N) deposition has increased dramatically in recent decades, which is significantly affecting the invasion and growth of exotic plants. Whether N deposition leads to invasive alien species becoming competitively superior to native species remains to be investigated. In the present study, an invasive species (Oenothera biennis L.) and three co-occurring native species (Artemisia argyi Lévl. et Vant., Inula japonica Thunb., and Chenopodium album L.) were grown in a monoculture (two seedlings of the same species) or mixed culture (one seedling of O. biennis and one seedling of a native species) under three levels of N deposition (0, 6, and 12 g∙m-2∙year-1). Nitrogen deposition had no effect on soil N and P content. Nitrogen deposition enhanced the crown area, total biomass, leaf chlorophyll content, and leaf N to phosphorus ratio in both invasive and native plants. Oenothera biennis dominated competition with C. album and I. japonica due to its high resource acquisition and absorption capacity (greater height, canopy, leaf chlorophyll a to chlorophyll b ratio, leaf chlorophyll content, leaf N content, leaf mass fraction, and lower root-to-shoot ratio). However, the native species A. argyi exhibited competitive ability similar to O. biennis. Thus, invasive species are not always superior competitors of native species; this depends on the identities of the native species. High N deposition enhanced the competitive dominance of O. biennis over I. japonica by 15.45% but did not alter the competitive dominance of O. biennis over C. album. Furthermore, N deposition did not affect the dominance of O. biennis or A. argyi. Therefore, the species composition of the native community must be considered when preparing to resist future biological invasions. Our study contributes to a better understanding of the invasion mechanisms of alien species under N-loading conditions.


Asunto(s)
Nitrógeno , Plantas , Clorofila A , Plantones , Clorofila , Especies Introducidas , Suelo
7.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 40(4): 632-637, 2023 Aug 25.
Artículo en Zh | MEDLINE | ID: mdl-37666752

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a progressive scar-forming disease with a high mortality rate that has received widespread attention. Epithelial mesenchymal transition (EMT) is an important part of the pulmonary fibrosis process, and changes in the biomechanical properties of lung tissue have an important impact on it. In this paper, we summarize the changes in the biomechanical microenvironment of lung tissue in IPF-EMT in recent years, and provide a systematic review on the effects of alterations in the mechanical microenvironment in pulmonary fibrosis on the process of EMT, the effects of mechanical factors on the behavior of alveolar epithelial cells in EMT and the biomechanical signaling in EMT, in order to provide new references for the research on the prevention and treatment of IPF.


Asunto(s)
Transición Epitelial-Mesenquimal , Fibrosis Pulmonar Idiopática , Humanos , Transducción de Señal
8.
Chin J Cancer Res ; 35(2): 176-190, 2023 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-37180834

RESUMEN

Objective: Ferroptosis is a novel cell death process which displays a promising role in cancer treatment. However, clinically available drugs targeting ferroptosis are rarely used, and yet there are no studies reporting on inducing ferroptosis via Chinese herbal extracts. Here we explored the tumor inhibition effects of Ganoderma lucidum (G. lucidum) on oral squamous cell carcinoma (OSCC). Specifically, we aimed to clarify the biological mechanism of components in the dietary, aqueous-soluble sporoderm-removed G. lucidum spore powder (A-GSP). Methods: Preliminary transcriptome analysis revealed the significant enrichment of the ferroptosis pathway. Cellular Fe2+, glutathione (GSH), malondialdehyde (MDA), reactive oxygen species (ROS) and lipid peroxide levels were measured to identify ferroptosis occurrence. Western blotting was used to measure ferroptosis-related proteins. Changes in mitochondria morphology and function were observed with transmission electron microscopy (TEM) and ATP detection assays. Ferroptosis inhibitor ferrostatin-1 was then used to verify the anti-tumor effects of A-GSP. Finally, nude mice xenograft models of oral cancer confirmed that A-GSP inhibited tumor growth. Results: A-GSP promoted ferroptosis in oral cancer cells by inducing Fe2+ influx, GSH depletion, as well as lipid peroxide and ROS accumulation. Ferroptosis-related proteins exhibited corresponding changes, particularly Acyl-coA synthetase long chain family member 4 (ACSL4) increase and glutathione peroxidase 4 (GPX4) decrease. A-GSP considerably lowered mitochondrial volume and ridge number, while significantly decreasing ATP production. Ferrostatin-1 reversed all of these A-GSP-induced changes. In vivo, A-GSP exerted a ferroptosis-mediated tumor-suppressing effect without observable adverse reactions. Conclusions: Our findings demonstrate the therapeutic potential of A-GSP for treating patients with OSCC by targeting ferroptosis.

9.
Neuroimage ; 261: 119525, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-35908606

RESUMEN

Association fibers connect the cortical regions and experience rapid development involving myelination and axonal growth during infancy. Yet, the spatiotemporal patterns of microstructural changes along these tracts, as well as the developmental interaction between the white matter (WM) tracts and the cortical gray matter (cGM) connected to them, are mostly unknown during infancy. In this study, we performed a diffusion MRI-based tractography and microstructure study in a cohort of 89 healthy preterm-born infants with gestational age at birth between 28.1∼36.4 weeks and postmenstrual age at scan between 39.9∼59.9 weeks. Results revealed that several C-shaped fibers, such as the arcuate fasciculus, cingulum, and uncinate fasciculus, demonstrated symmetrical along-tract profiles; and the horizontally oriented running fibers, including the inferior fronto-occipital fasciculus and the inferior longitudinal fasciculus, demonstrated an anterior-posterior developmental gradient. This study characterized the along-tract profiles using fixel-based analysis and revealed that the fiber cross-section (FC) of all five association fibers demonstrated a fluctuating increase with age, while the fiber density (FD) monotonically increase with age. NODDI was utilized to analyze the microstructural development of cGM and indicated cGM connected to the anterior end of the association fibers developed faster than that of the posterior end during 0-5 months. Notably, a mediation analysis was used to explore the relation between the development of WM and associated cGM, and demonstrated a partial mediation effect of FD in WM on the development of intracellular volume (ICV) in cGM and a full mediation effect of ICV on the growth of FD in most fibers, suggesting a predominant mediation of cGM on the WM development. Furthermore, for assessing whether those results were biased by prematurity, we compared preterm- and term-born neonates with matched scan age, gender, and multiple births from the developing human connectome project (dHCP) dataset to assess the effect of preterm-birth, and the results indicated a similar developmental pattern of the association fibers and their attached cGM. These findings presented a comprehensive picture of the major association fibers during early infancy and deciphered the developmental interaction between WM and cGM in this period.


Asunto(s)
Encéfalo , Sustancia Blanca , Encéfalo/diagnóstico por imagen , Imagen de Difusión Tensora/métodos , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Red Nerviosa , Sustancia Blanca/diagnóstico por imagen
10.
Thorax ; 2021 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-33593930

RESUMEN

BACKGROUND: As the epidemic of COVID-19 is gradually controlled in China, a summary of epidemiological characteristics and interventions may help control its global spread. METHODS: Data for COVID-19 cases in Hubei Province (capital, Wuhan) was extracted until 7 March 2020. The spatiotemporal distribution of the epidemic in four periods (before 10 January, 10-22 January, 23 January-6 February and 7 February-7 March) was evaluated, and the impacts of interventions were observed. RESULTS: Among 67 706 COVID-19 cases, 52 111 (76.97%) were aged 30-69 years old, and 34 680 (51.22%) were women. The average daily attack rates (95% CI) were 0.5 (0.3 to 0.7), 14.2 (13.2 to 15.1), 45.7 (44.0 to 47.5) and 8.6 (7.8 to 9.3) cases per 106 people in four periods, and the harmonic means (95% CI) of doubling times were 4.28 (4.01 to 4.55), 3.87 (3.78 to 3.98), 5.40 (4.83 to 6.05) and 45.56 (39.70 to 52.80) days. Compared with the first period, daily attack rates rose rapidly in the second period. In the third period, 14 days after 23 January, the daily average attack rate in and outside Wuhan declined by 33.8% and 48.0%; the doubling times increased by 95.0% and 133.2%. In the four periods, 14 days after 7 February, the daily average attack rate in and outside Wuhan decreased by 79.1% and 95.2%; the doubling times increased by 79.2% and 152.0%. CONCLUSIONS: The public health interventions were associated with a reduction in COVID-19 cases in Hubei Province, especially in districts outside of Wuhan.

11.
Scand J Immunol ; 93(3): e12996, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33205443

RESUMEN

Intestinal T cells form a central part of the front-line defence against foreign organisms and need to be situated in the mucosa where infection occurs. It is well accepted that immunization by a mucosal route favours localization of antigen-specific effector T cells in the mucosal epithelium, while systemic immunization does not. The aim of the study is to determine how homing receptors are specifically involved in retaining effector T cells in the small intestine after oral immunization. We here demonstrate that the chemokine receptor CXCR6, integrins ß7 and CD29 contribute differentially to the epithelial retention phenotype of CD8+ T cells in the small intestine of mice. CD8+ intraepithelial lymphocytes (IELs) of unvaccinated mice are predominantly ß7 single positives, and subcutaneous immunization-induced antigen-specific CD8+ effector IELs are mainly composed of CXCR6+ , CD29+ and CXCR6+ CD29+ cells. Strikingly, the majority of oral immunization-induced antigen-specific CD8+ effector IELs exhibit a distinct, tissue-specific CXCR6+ ß7+ double-positive phenotype, cytotoxic potential and enhanced intraepithelial localization. Transfer of antigen-specific CD8+ T cells preactivated with certain immuno-stimuli (such as monophosphoryl lipid A) results in increased accumulation of donor IELs with the CXCR6+ ß7+ phenotype. As ß7 exclusively paired with αE on IELs, our results strongly suggest that CXCR6 may cooperate with the heterodimer αEß7 to preferentially retain intestinally induced effector IELs in the epithelium. The identification of this novel IEL phenotype has significant implications for the development of vaccines and therapeutic strategies to enhance gut immunity.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Cadenas beta de Integrinas/metabolismo , Intestino Delgado/inmunología , Linfocitos Intraepiteliales/inmunología , Receptores CXCR6/metabolismo , Traslado Adoptivo , Animales , Linfocitos T CD8-positivos/trasplante , Integrina beta1/metabolismo , Mucosa Intestinal/citología , Mucosa Intestinal/inmunología , Intestino Delgado/citología , Linfocitos Intraepiteliales/trasplante , Listeria monocytogenes/inmunología , Activación de Linfocitos/inmunología , Subgrupos Linfocitarios/inmunología , Subgrupos Linfocitarios/metabolismo , Ratones , Ratones Endogámicos C57BL , Vacunación
12.
Mol Pharm ; 18(4): 1573-1581, 2021 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-33629860

RESUMEN

Berberine (BBR) is currently explored in the oral treatment of many disorders, especially in those involving inflammatory processes. Nanotechnology-based drug delivery systems are emerging as an effective approach for improving the poor oral absorption/bioavailability of BBR. To optimize the BBR immunoregulatory effects on a specific part of the gastrointestinal tract, here we describe a micro- and nanoencapsulated hybrid delivery system (MNEHDS) for colon-targeted oral delivery of BBR and test its therapeutic efficacy in a murine colitis model. The MNEHDS is formed by encapsulation of BBR-loaded poly(lactic-co-glycolic acid) nanoparticles into a pH-sensitive, BBR-pre-entrapped Eudragit FS30D matrix to form a hybrid microparticle composed of the BBR and BBR nanoparticles. Once in the colonic environment, the microencapsulated BBR is almost completely released for immediate action, while BBR nanoparticles can provide sustained release of BBR subsequent to their intestinal absorption. One dose of oral MNEHDS/BBR treatment results in significant attenuation of acute colitis induced by dextran sulfate sodium. The MNEHDS/BBR also proves to be effective during chronically induced colitis with two doses given 1 week apart. The improved efficacy is accompanied by decreased production of colon inflammation. Comparatively, oral treatment with one or two 7-day courses of free BBR has less effect on ameliorating either acute or chronic colitis. Thus, MNEHDS represents a novel delivery system for BBR, and potentially other therapeutic agents, to treat inflammatory bowel disease.


Asunto(s)
Berberina/administración & dosificación , Colitis/tratamiento farmacológico , Sistemas de Liberación de Medicamentos/métodos , Administración Oral , Animales , Berberina/farmacocinética , Colitis/inducido químicamente , Colitis/patología , Colon/efectos de los fármacos , Colon/patología , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/farmacocinética , Sulfato de Dextran/administración & dosificación , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Liberación de Fármacos , Femenino , Humanos , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Ratones , Nanopartículas/química , Tamaño de la Partícula , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Ácidos Polimetacrílicos/química
13.
BMC Pulm Med ; 21(1): 252, 2021 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-34332565

RESUMEN

OBJECTIVE: This study aimed to determine the effects of emodin on the viability, proliferation and apoptosis of human pulmonary artery smooth muscle cells (PASMCs) under hypoxia and to explore the underling molecular mechanisms. METHODS: PASMCs were cultured in a hypoxic environment (1% oxygen) and then treated with emodin. Cell viability, proliferation and apoptosis were evaluated using CCK-8 assay, EdU staining assay, western blot and Mito-tracker red CMXRos and Annexin V-FITC apoptosis detection assay. The microRNA (miRNA)/mRNA and protein expression levels were assessed by quantitative real-time PCR and western blotting, respectively. Based on transcriptomics and proteomics were used to identify potential signaling pathways. Luciferase reporter assay was utilized to examine the interaction between miR-244-5p and DEGS1. RESULTS: Emodin at 40 and 160 µM concentration-dependently suppressed cell viability, proliferation and migration, but enhanced cell apoptosis of PASMCs under hypoxia. Transcriptomic and proteomic analysis revealed that emodin could attenuate the activity of PI3K/Akt signaling in PASMCs under hypoxia. In addition, delta 4-desaturase, sphingolipid 1 (DEGS1) was found to be a direct target of miR-244-5p. Emodin could significantly up-regulated miR-244-5p expression and down-regulated DEGS1 expression in PASMCs under hypoxia. Furthermore, emodin-mediated effects on cell viability, migration, apoptosis and PI3K/Akt signaling activity of PASMCs under hypoxia were significantly attenuated by miR-244-5p knockdown. CONCLUSIONS: Our results indicated that emodin suppressed cell viability, proliferation and migration, promoted cell apoptosis of PASMCs under hypoxia via modulating miR-244-5p-mediated DEGS1/PI3K/Akt signaling pathway. MiR-244-5p/DEGS1 axis was initially investigated in this current study, which is expected to further the understanding of the etiology of pulmonary arterial hypertension.


Asunto(s)
Emodina/farmacología , Ácido Graso Desaturasas/metabolismo , MicroARNs/metabolismo , Músculo Liso Vascular , Miocitos del Músculo Liso/fisiología , Arteria Pulmonar , Apoptosis/efectos de los fármacos , Hipoxia de la Célula/fisiología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Ácido Graso Desaturasas/genética , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/fisiología , Humanos , MicroARNs/genética , Transducción de Señal/efectos de los fármacos
14.
J Paediatr Child Health ; 57(5): 637-645, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33289923

RESUMEN

AIM: This study aimed to identify the epidemiological characteristics and transmission dynamics of paediatric cases. METHODS: Information on 1369 paediatric cases with COVID-19 from 8 December 2019 to 7 March 2020 in Hubei province was extracted from the National Infectious Disease Surveillance System. The analysis included epidemic curves, temporal-spatial distribution, clinical classification and interval times between onset and diagnosis. RESULTS: Among 1369 paediatric cases, the median age was 9 years and 58.2% of them were males. The proportion of severe and critical cases in children was lower than that in adults and the proportion of asymptomatic cases in children was five times greater than for adult cases. The first paediatric case was reported on 2 January 2020, and the daily number of new paediatric cases remained high from 1 February through to 22 February. The epidemiological curve of paediatric cases lagged behind that of adults by 19 days, and the first spike of the epidemic curve in senior high school students occurred 1 week earlier than in other paediatric groups. The proportion of clustered cases among children was about twice that for adults. The median of the interval in paediatric cases between onset and diagnosis, isolation and notification were 3, 0 and 3 days, respectively, and all of those were significantly shorter than in adults. CONCLUSIONS: The epidemic curve of child cases lagged behind that of adult cases by 19 days, and the major form of transmission observed was in clusters.


Asunto(s)
COVID-19 , Adulto , Niño , China/epidemiología , Femenino , Humanos , Masculino , SARS-CoV-2
15.
NMR Biomed ; 33(10): e4369, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32729642

RESUMEN

The neuroimaging of nonhuman primates (NHPs) realised with magnetic resonance imaging (MRI) plays an important role in understanding brain structures and functions, as well as neurodegenerative diseases and pathological disorders. Theoretically, an ultrahigh field MRI (≥7 T) is capable of providing a higher signal-to-noise ratio (SNR) for better resolution; however, the lack of appropriate radiofrequency (RF) coils for 9.4 T monkey MRI undermines the benefits provided by a higher field strength. In particular, the standard volume birdcage coil at 9.4 T generates typical destructive interferences in the periphery of the brain, which reduces the SNR in the neuroscience-focused cortex region. Also, the standard birdcage coil is not capable of performing parallel imaging. Consequently, extended scan durations may cause unnecessary damage due to overlong anaesthesia. In this work, assisted by numerical simulations, an eight-channel receive RF coil array was specially designed and manufactured for imaging NHPs at 9.4 T. The structure and geometry of the proposed receive array was optimised with numerical simulations, so that the SNR enhancement region was particularly focused on monkey brain. Validated with rhesus monkey and cynomolgus monkey brain images acquired from a 9.4 T MRI scanner, the proposed receive array outperformed standard birdcage coil with higher SNR, mean diffusivity and fractional anisotropy values, as well as providing better capability for parallel imaging.


Asunto(s)
Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/instrumentación , Ondas de Radio , Animales , Simulación por Computador , Imagen de Difusión por Resonancia Magnética , Macaca fascicularis , Macaca mulatta , Ratones , Fantasmas de Imagen , Relación Señal-Ruido
16.
Respir Res ; 21(1): 257, 2020 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-33032592

RESUMEN

BACKGROUND: Coronavirus Disease 2019 (COVID-19) spread rapidly around the world. We aimed to describe the epidemiological characteristics and the entire evolution of COVID-19 in Wuhan, and to evaluate the effect of non-pharmaceutical intervention by the government. METHODS: The information of COVID-19 cases until Mar 18, 2020 in Wuhan were collected from the national infectious disease surveillance system in Hubei province. RESULTS: A total of 49,973 confirmed cases were reported until Mar 18, 2020 in Wuhan. Among whom, 2496 cases died and the overall mortality was 5.0%. Most confirmed cases (25,619, 51.3%) occurred during Jan 23 to Feb 4, with a spike on Feb 1 (new cases, 3374). The number of daily new cases started to decrease steadily on Feb 19 (new cases, 301) and decreased greatly on Mar 1 (new cases, 57). However, the mortality and the proportion of severe and critical cases has been decreasing over time, with the lowest of 2.0 and 10.1% during Feb 16 to Mar 18, 2020, respectively. The percentage of severe and critical cases among all cases was 19.6%, and the percentage of critical and dead cases aged over 60 was 70.1 and 82.0%, respectively. CONCLUSION: The number of new cases has dropped significantly after the government taking the isolation of four types of personnel and the community containment for 14 days. Our results indicate that the mortality and proportion of severe and critical cases gradually decreased over time, and critical and dead cases are more incline to be older individuals.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/epidemiología , Agencias Gubernamentales , Pandemias/prevención & control , Neumonía Viral/epidemiología , Aislamiento Social , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19 , Niño , Preescolar , China/epidemiología , Infecciones por Coronavirus/diagnóstico , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Neumonía Viral/diagnóstico , SARS-CoV-2 , Adulto Joven
17.
Am J Med Genet A ; 182(9): 2102-2109, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32706523

RESUMEN

To describe special facial features of children with Williams syndrome in China by using method of three-dimensional craniofacial anthropometry. Using three-dimensional stereo photogrammetric device, 14 craniofacial anthropometric measurements were performed and five indices were calculated in 52 children with Williams syndrome and 208 age and sex matched controls of Han Chinese ethnicity. Except intercanthal width, mouth breadth, morphological face height, nasal height-breadth index, nasal breadth-depth index, morphological ear index, the Williams syndrome group under 3 years old were smaller than the control group in the other 12 variables. Compared with the control group, the Williams syndrome group aged 3-5 years old had smaller biocular breadth, nasal length, nasorostral angle, bitragal breadth, ear width, morphological ear index and face depth. The Williams syndrome group aged above 6 years old had smaller biocular breadth, nasal breadth, bitragal breadth, ear width, ear length and face depth than the control group. The craniofacial variability index of the Williams syndrome group was greater than the control group. Greater variation was found among children with Williams syndrome than normal in China, specifically at eye, nose, ear and face shape, which demonstrate the usefulness of three-dimensional stereo photogrammetric analysis in supporting accurate diagnose of the patient with Williams syndrome.


Asunto(s)
Antropometría , Cara/anomalías , Cráneo/anomalías , Síndrome de Williams/genética , Pueblo Asiatico/genética , Cefalometría , Niño , Preescolar , China/epidemiología , Oído/anomalías , Oído/patología , Cara/patología , Femenino , Humanos , Masculino , Nariz/anomalías , Nariz/patología , Cráneo/patología , Síndrome de Williams/patología
18.
BMC Ecol ; 20(1): 17, 2020 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-32228576

RESUMEN

BACKGROUND: Invasive exotic species have caused significant problems, and the effects of extreme precipitation and drought, which might occur more frequently under the global climate change scenarios, on interspecific relationship between invasive and native species remain unclear. RESULTS: We conducted a greenhouse experiment with three soil water levels (30-40%, 50-60%, and 70-80% of field capacity) and two cultivation treatments (monoculture pots, one seedling of either species and mixture pots, one seedling of each species) to investigate soil water content effects on the relationship between invasive Rhus typhina and native Cotinus coggygria. Rhus typhina had lower height but bigger crown area than C. coggygria in the monoculture treatment. Rhus typhina had higher height, bigger crown area and total biomass than C. coggygria in the mixture treatment. Drought decreased the growth parameters, total chlorophyll concentration, and leaf biomass, but did not change gas exchange and other biomass parameters in R. typhina. The growth parameters, leaf area index, biomass parameters, total chlorophyll concentration, and net photosynthetic rate of C. coggygria decreased under drought conditions. The log response ratio (lnRR), calculated as ln (total biomass of a target plant grown in monoculture/total biomass of a target plant grown in mixed culture), of R. typhina was lower than that of C. coggygria. The lnRR of R. typhina and C. coggygria decreased and increased with increase in soil water content, respectively. CONCLUSIONS: Rhus typhina has greater capacity to relatively stable growth to the drought condition than C. coggygria and has strong competition advantages in the mixture with C. coggygria, especially in the drought condition. Our study will help understand the causes of invasiveness and wide distribution of R. typhina under various moisture conditions and predict its expansion under climate change scenarios.


Asunto(s)
Anacardiaceae , Rhus , Biomasa , Sequías , Fotosíntesis , Suelo , Árboles
19.
Blood Cells Mol Dis ; 77: 113-119, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31030124

RESUMEN

PURPOSE: The present study aimed to identify the molecular mechanism of acute lymphoblastic leukemia (ALL), and explore valuable prognostic biomarkers for relapsed ALL. METHODS: Gene expression dataset including 59 samples from ALL survivals without recurrence (good group) and 114 samples from dead ALL patients died of recurrence (poor group) was downloaded from TCGA database. The differentially expressed genes (DEGs) were identified between good and poor groups, followed by pathway and functional enrichment analyses. Subsequently, logistic regression model and survival analysis were performed. RESULTS: In total, 637 up- and 578 down-regulated DEGs were revealed between good and poor groups. These DEGs were mainly enriched in functions including transcription and pathways like focal adhesion. Genes including alpha-protein kinase 1 (ALPK1), zinc finger protein 695 (ZNF695), actinin alpha 4 (ACTN4), calreticulin (CALR), and F-Box and leucine rich repeat protein 5 (FBXL5) were outstanding in survival analysis. CONCLUSION: Transcription and focal adhesion might play important roles in ALL progression. Furthermore, genes including ALPK1, ZNF695, ACTN4, CALR, and FBXL5 might be novel prognostic genes for relapsed ALL.


Asunto(s)
Biomarcadores de Tumor/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Biología Computacional/métodos , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Ontología de Genes , Redes Reguladoras de Genes , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Pronóstico , Recurrencia , Análisis de Supervivencia
20.
Environ Res ; 172: 486-494, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30851698

RESUMEN

INTRODUCTION: Despite widespread use, many herbicides and fungicides are not well studied for neurological effects. Fetal and infant brains are rapidly developing, yet the effects of early-life exposure to these classes of pesticides on visual and auditory function are unknown. Here we examined the effects of prenatal herbicide and fungicide exposure on infant grating visual acuity (VA) and auditory brainstem response (ABR). METHODS: 9 herbicides and 13 fungicides were measured in umbilical cord blood plasma from a cohort of infants in Fuyang County, China (n = 232). Grating VA and ABR latencies for waves I, III, V were measured at 3 time points: 6 weeks, 9 months, and 18 months. Outcomes included VA score, ABR wave V latency and ABR central conduction time (CCT [wave V- wave I]). Pesticides were analyzed as 3-level ordinal (non-detect [ND]/medium/high), or dichotomous (ND/detect), depending on detection rates. Linear mixed models were used to evaluate relations between pesticides and VA and ABR outcomes. RESULTS: 2,4-dichloroacetic acid (2,4-D), prometryn, simazine, and tetrahydrophthalamide (THPI, a metabolite of captan) were detected in 27%, 81%, 17%, and 16% of samples, respectively. Infants prenatally exposed to 2,4-D had slower auditory response times at 6 weeks. Infants with cord levels of 2,4-D > 1.17 ng/mL had wave V latencies that were 0.12 (95% CI: 0.03, 0.22) ms slower (p = 0.01) and overall CCTs that were 0.15 (95% CI:0.05, 0.25) ms slower (p = 0.003) than infants with non-detectable 2,4-D in their cord blood. No other statistically significant findings were observed for the other herbicides and fungicides or for the grating VA outcome. CONCLUSIONS: Prenatal exposure to the herbicide 2,4-D was associated with slower auditory signal transmission in early infancy. ABR latencies reflect auditory pathway maturation and longer latencies may indicate delayed auditory development.


Asunto(s)
Ácido 2,4-Diclorofenoxiacético , Trastornos de la Percepción Auditiva , Herbicidas , Efectos Tardíos de la Exposición Prenatal , Ácido 2,4-Diclorofenoxiacético/toxicidad , Trastornos de la Percepción Auditiva/inducido químicamente , China , Potenciales Evocados Auditivos del Tronco Encefálico/efectos de los fármacos , Femenino , Herbicidas/toxicidad , Humanos , Lactante , Masculino , Embarazo
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