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1.
Org Biomol Chem ; 22(18): 3611-3614, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38630011

RESUMEN

Herein, we report that prism[6]arenes (PrS[6]R) can form charge-transfer (CT) inclusion complexes with tropylium tetrakis[3,5-bis(trifluoromethyl)-phenyl]borate (G) in chloroform solution with an obvious CT band at 560 nm. Moreover, the CT complex PrS[6]Et⊃G showed Cl-/Ag+ responsiveness which can be easily monitored by the naked eye.

2.
Biomed Chromatogr ; 36(10): e5437, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35766796

RESUMEN

A rapid, simple, and economical method has been developed to determine colchicine in both human whole blood and urine using UPLC-MS/MS. Colchicine and isotope-labeled internal standard were extracted from the matrix by liquid-liquid extraction with saturated borax and ethyl acetate, and separated by a reversed-phase chromatography C18 column. Gradient elution was carried out using acetonitrile and water spiked with 0.01% formic acid. Multiple reaction monitoring was performed at positive ion mode. The quantitative transitions were m/z 400.27 → 310.28 for colchicine and m/z 406.16 → 313.18 for colchicine-D6. The method has good linearity in the range of 0.5-200 ng/mL for blood and 2-2000 ng/mL for urine. The sensitivity, accuracy, and matrix effect were all in line with the guidelines of Food and Drug Administration and European Medicines Agency. The extraction recovery was above 63.94%. The samples were stable under various storage conditions. Six deuterium-substituted isotopic internal standard was used to demonstrate a different mode of colchicine cleavage from the existing literature. This method has been successfully used in the diagnosis of patients with colchicine poisoning. Blood is recommended as the optimal sample compared with urine.


Asunto(s)
Colchicina , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida/métodos , Humanos , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/métodos
3.
Rev Cardiovasc Med ; 22(1): 167-174, 2021 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-33792258

RESUMEN

Our objective was to systematically evaluate the efficacy and safety of proton pump inhibitors combined with clopidogrel in patients undergoing percutaneous coronary intervention and to provide an evidence basis for clinical treatment decision-making. The database EMBASE, PubMed/Medline, Web of Science, the Cochrane Library and CNKI records from establishment of each database until August 2020 were included. Articles were evaluated for quality. Meta-analysis of selected articles was conducted by RevMan5.3 software. Three RCTs and 4 cohort studies were included, with a total of 9932 patients. Four studies reported gastrointestinal (GI) bleeding events, 3 of which were RCT studies. Overall, there was a significantly lower risk of GI bleeding events in the PPI group compared to the no PPI group [OR = 3.06, 95% CI: 1.89 to 4.95] (P < 0.00001). In 3 RCT studies, there was also a significantly lower risk of GI bleeding events in the PPI group compared to the no PPI group [OR = 3.06, 95% CI: 1.80 to 5.21] (P < 0.0001). Seven studies including 3 RCTs and 4 cohort studies reported MACE. Overall, there was no significant difference in MACE events between PPI group and no PPI group [OR = 1.05, 95% CI: 0.91 to 1.21] (P = 0.50). Both in RCT and cohort studies subgroups, there also was no significant difference in MACE events between the PPI group and the no PPI group [OR = 1.16, 95% CI: 0.87 to 1.53] (P = 0.32), [OR = 1.02, 95% CI: 0.87 to 1.19] (P = 0.84), respectively. For PCI patients taking clopidogrel and PPI therapy, PPI reduced the risk of GI bleeding while having no impact on MACE.


Asunto(s)
Intervención Coronaria Percutánea , Inhibidores de la Bomba de Protones , Clopidogrel/efectos adversos , Humanos , Intervención Coronaria Percutánea/efectos adversos , Inhibidores de Agregación Plaquetaria/efectos adversos , Inhibidores de la Bomba de Protones/efectos adversos , Ticlopidina/efectos adversos , Resultado del Tratamiento
4.
Inorg Chem ; 58(16): 10648-10655, 2019 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-31348657

RESUMEN

Stimulated by the recent successful synthesis and crystallographic characterization of the first diuranium carbide endohedral metallofullerene (EMF) U2C@Ih(7)-C80 ( Zhang et al. Nat. Commun. ; 2018 ), density functional theory calculations were performed for a series of U2C@C2n (2n = 60, 68, 72, 78, 80, 88, 96, and 104) analogues. The internal UCU bond angle increases from 96.9° in Ih-C60 to 180.0° in D3d-C104, exhibiting cage-size-dependent cluster configuration. However, further evidence suggests that the U2C shape may be also affected by the amount of charge transferred from the cluster to the outer cage with 6e and 4e favoring bent and linear, respectively. The change of the bond angle closely correlates with the charge and hybrid state of the internal atom. Significantly, besides the covalent two-center two-electron (2c-2e) U-C bonds, the U2C unit always features two 3c-2e bonds regardless of its size, shape, and charge state. Furthermore, for the cluster-cage interactions, besides the dominated electrostatic attractions, all these EMFs show an obvious covalent character with the substantial participation of U 5f valence orbitals.

5.
Mol Pharm ; 15(9): 3860-3870, 2018 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-30036479

RESUMEN

Nonalcoholic fatty liver disease (NAFLD), as a common chronic liver disorder, is prevalent in the world. Recent evidence demonstrates that the "gut-liver axis" is related well to the progression of NAFLD, which regards gut microbiota and the intestinal barrier as two critical factors correlated with NAFLD. Diammonium glycyrrhizinate (DG), a compound of the natural bioactive pentacyclic triterpenoid glycoside, is the main component of licorice root extracts. The anti-inflammatory and liver protection effects of DG have already been reported, but to date, the mechanism has not been fully elucidated. In this research, we observed that DG reduced body weight, liver steatosis, as well as hepatic inflammation in NAFLD model mice induced by a high-fat diet. Illumina sequencing of the 16S rRNA revealed that DG intervention notably altered the composition of the gut microbiota in NAFLD mice. The richness of gut microbiota was significantly increased by DG. Specifically, DG reduced the Firmicutes-to- Bacteroidetes ratio and the endotoxin-producing bacteria such as Desulfovibrio and elevated the abundance of probiotics such as Proteobacteria and Lactobacillus. DG could augment the levels of short-chain fatty acid (SCFA)-producing bacteria such as Ruminococcaceae and Lachnospiraceae and promote SCFA production. In addition, DG supplementation dramatically alleviated the intestinal low-grade inflammation. Meanwhile, DG improved the expression of tight junction proteins, the goblet cell number, and mucin secretion and sequentially enhanced the function of intestinal barrier. Collectively, the prevention of NAFLD by DG might be mediated by modulating gut microbiota and restoring the intestinal barrier.


Asunto(s)
Antiinflamatorios/farmacología , Microbioma Gastrointestinal/efectos de los fármacos , Ácido Glicirrínico/farmacología , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Animales , Inmunohistoquímica , Intestinos/efectos de los fármacos , Intestinos/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Reacción en Cadena en Tiempo Real de la Polimerasa
6.
Artículo en Zh | MEDLINE | ID: mdl-25902686

RESUMEN

Malaria data in 2011-2013 were collected and statistically analyzed using Microsoft Excel 2003 software. A total of 501 malaria cases were reported, and the annual incidence was 0.2510/100,000, 0.2486/100,000, and 0.3223/100,000, in 2011, 2012, and 2013, respectively, with an average of 0.2740/100,000 in Hunan Province. All these cases were imported and mainly reported from Changsha (44.3%, 222/501), Shaoyang (16.6%, 83/501), Huaihua (8.4%, 42/501), and Yiyang (8.0%, 40/501). 97.0% (486/501) of the cases were laboratory confirmed cases, while the other 3.0% (15/501) were clinically diagnosed. Among those lab confirmed, 41.3% (207/501) were vivax malaria cases, 47.9% (240/501) falciparum malaria cases, 1.4% (7/501) ovale malaria cases, 0.8% (4/501) malariae cases, 6.6% (33/501) mixed infection, and 2.0% (10/501) were unclassified cases. Most cases (202/501) occurred among persons aged 40-49 years. These patients were mainly farmers, workers, migrant workers, and cadres. 47.7% (239/501) were from Africa and 50.1% (251/501) from Southeast Asia.


Asunto(s)
Malaria , China , Coinfección , Humanos , Incidencia , Malaria Falciparum , Malaria Vivax
7.
Sci Bull (Beijing) ; 68(4): 436-440, 2023 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-36739241

RESUMEN

Periodic assembly and break-up of supercontinents since at least two billion years ago (Ga), dubbed the supercontinent cycle, provides the first-order tectonic control on the evolution of the Earth System including episodic orogenic events, mineralization, the formation and closure of oceans and superoceans, and even the evolution of life. However, the lifespan of the supercontinents appears to decrease with time, from ∼300 million years (Myr) for Nuna/Columbia, to 200-250 Myr for Rodinia and ∼150 Myr for the youngest supercontinent Pangaea. To understand what caused such a secular decrease in supercontinental lifespan, we conduct 3-D geodynamic modeling using realistic tectonic settings. The results show that the yield stress of newly formed orogens during the assembly of a supercontinent provides the dominant control on the lifespan of the supercontinent, implying that the yield stress of young orogens becomes lower with time. We hypothesize that the decreasing mantle temperature due to Earth's secular cooling might have caused new orogens to become weaker.

8.
Biotechnol Genet Eng Rev ; : 1-20, 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37066859

RESUMEN

This research wasdesigned to provide a visual analysis of the current status, hotspots, and trends of global acupuncture for dysmenorrhea over the past 2 decades. The literature about acupuncture for dysmenorrhea from the Web of Science Core Collection database. Cite Space (5.6.R3) was used to analyze the volume of publications, journals, authors, cited journals, cited authors, countries, cited references, institutions, and keywords by using standard bibliometric measures. The most productive countries and institutions in this area were China (79) and BeijingUniversity of Chinese Medicine (24). The Evidence-Based Complementary and Alternative Medicine was the most published journal (29) and also had the highest number of citations (80). The article by Woo HL (2018) (number of citations: 13) and the article by (centrality: 0.38) were the most representative references. JiangZhu (17) was the most productive author and Dawood MY (47) was the top cited author. The number one keyword in terms of frequency and centrality was 'primary dysmenorrhea", and the leading hotspot from 2002 to 2022 was "Functional connectivity". The three forefront topics were "prevalence", "impact"and "point'. This research is thefirst bibliometric analysis of the current situation and new trends about acupuncture for dysmenorrhea in the past 20 years using CiteSpace. It offered some information on acupuncture for dysmenorrhea and valuable information for researchers to identify prospective collaborators, partner institutions, popular topics, and research frontiers.

9.
Nat Commun ; 14(1): 5274, 2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37726314

RESUMEN

Argyle is the world's largest source of natural diamonds, yet one of only a few economic deposits hosted in a Paleoproterozoic orogen. The geodynamic triggers responsible for its alkaline ultramafic volcanic host are unknown. Here we show, using U-Pb and (U-Th)/He geochronology of detrital apatite and detrital zircon, and U-Pb dating of hydrothermal titanite, that emplacement of the Argyle lamproite is bracketed between 1311 ± 9 Ma and 1257 ± 15 Ma (2σ), older than previously known. To form the Argyle lamproite diatreme complex, emplacement was likely driven by lithospheric extension related to the breakup of the supercontinent Nuna. Extension facilitated production of low-degree partial melts and their migration through transcrustal corridors in the Paleoproterozoic Halls Creek Orogen, a rheologically-weak rift zone adjacent to the Kimberley Craton. Diamondiferous diatreme emplacement during (super)continental breakup may be prevalent but hitherto under-recognized in rift zones at the edges of ancient continental blocks.

10.
Natl Sci Rev ; 9(12): nwac205, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36519070

RESUMEN

Earth's known supercontinents are believed to have formed in vastly different ways, with two endmembers being introversion and extroversion. The former involves the closure of the internal oceans formed during the break-up of the previous supercontinent, whereas the latter involves the closure of the previous external superocean. However, it is unclear what caused such diverging behavior of supercontinent cycles that involved first-order interaction between subducting tectonic plates and the mantle. Here we address this question through 4D geodynamic modeling using realistic tectonic set-ups. Our results show that the strength of the oceanic lithosphere plays a critical role in determining the assembly path of a supercontinent. We found that high oceanic lithospheric strength leads to introversion assembly, whereas lower strength leads to extroversion assembly. A theoretically estimated reduction in oceanic crustal thickness, and thus its strength, during Earth's secular cooling indicates that introversion was only possible for the Precambrian time when the oceanic lithosphere was stronger, thus predicting the assembling of the next supercontinent Amasia through the closure of the Pacific Ocean instead of the Indian-Atlantic oceans. Our work provides a new understanding of the secular evolution of plate tectonics and geodynamics as the Earth cooled.

11.
Artículo en Inglés | MEDLINE | ID: mdl-36084166

RESUMEN

A new efficient magnetic solid-phase extractant based on a surface-modified magnetic mesoporous silica microsphere referred as MMSM-PEI was synthesised and used for the enrichment and isolation of copper ions (Cu2+) in preserved eggs. The physicochemical properties and morphology of MMSM-PEI were characterized by X-ray diffraction (XRD) spectroscopy, Fourier transform infrared spectroscopy (FT-IR), vibration sample magnetometry (VSM), scanning electron microscopy (SEM) and thermos-gravimetric analyses (TGA). The concentrations of trace Cu2+ in the preserved egg were determined by flame atomic absorption spectroscopy (FAAS). The effects of important parameters were examined. The most suitable pH values and temperature for adsorbing Cu2+ were 6.5 and 25 °C, respectively. According to the determination of Cu2+ in egg white, egg yolk and the outer coating mixture (TOCM) of preserved eggs, the spiked recovery and RSD were 94.1-103.8% and 0.96-4.35%, respectively. The limit of detection (LOD) and the limit of quantitation (LOQ) were 0.14 mg/kg and 0.46 mg/kg, respectively. The developed method improved the sensitivity and accuracy of FAAS for the determination of Cu2+ and it could be applied to the determination of trace Cu2+ in real samples.


Asunto(s)
Polietileneimina , Dióxido de Silicio , Espectrofotometría Atómica/métodos , Dióxido de Silicio/química , Polietileneimina/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Extracción en Fase Sólida/métodos , Microesferas , Temperatura , Cobre/análisis , Digestión , Fenómenos Magnéticos , Adsorción
12.
Front Bioinform ; 2: 836981, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36304284

RESUMEN

Background: Hepatocellular carcinoma (HCC) is a common malignant cancer. Metastasis plays a critical role in tumor progression, and vascular invasion is considered one of the most crucial factors for HCC metastasis. However, comprehensive analysis focusing on competitive endogenous RNA (ceRNA) and immune infiltration in the vascular invasion of HCC is lacking. Methods: The gene expression profiles of 321 samples, including 210 primary HCC cases and 111 HCC cases with vascular invasion, were downloaded from The Cancer Genome Atlas-Liver Hepatocellular Carcinoma project, and used in identifying significant differentially expressed lncRNAs (DElncRNAs), miRNAs (DEmiRNAs), and mRNAs (DEmRNAs). The RNAs associated with vascular invasion were used in constructing a ceRNA network. A multigene-based risk signature was constructed using the least absolute shrinkage and selection operator algorithm. We detected the fractions of 28 immune cell types in HCC through single-sample gene set enrichment analysis (ssGSEA). Finally, the relationship between the ceRNA network and immune cells was determined through correlation analysis and used in clarifying the potential mechanism involved in vascular invasion. Results: Overall, 413 DElncRNAs, 27 DEmiRNAs, and 397 DEmRNAs were recognized in HCC. A specific ceRNA network based on the interaction among 3 lncRNA-miRNA pairs and 24 miRNA-mRNA pairs were established. A ceRNA-based prognostic signature was constructed and used in dividing samples into high- and low-risk subgroups. The signature showed significant efficacy; its 3- and 5-year areas under the receiver operating characteristic curves were 0.712 and 0.653, respectively. ceRNA and ssGSEA integration analysis demonstrated that PART1 (p = 0, R = -0.33) and CDK5R2 (p = 0.01, R = -0.15) were negatively correlated to natural killer cells. Conclusion: This study demonstrated that vascular invasion in HCC might be related to PART1, and its role in regulating CDK5R2 and NK cells. A nomogram was developed to predict the prognosis of patients with HCC and demonstrated the value of the ceRNA network and tumor-infiltrating immune cells value in improving personalized management.

13.
J Evid Based Med ; 15(3): 302-314, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36151612

RESUMEN

Severe mechanical ocular trauma with no light perception (NLP) predicts a poor prognosis of visual acuity and enucleation of the eyeball. Since the innovative treatment concept of exploratory vitreoretinal surgery has developed and treatment technology has advanced, the outcomes of severe ocular trauma treatment in NLP patients have greatly improved. However, there remains a lack of unified standards for the determination, surgical indication, and timing of vitrectomy in NLP eye treatment. To address these problems, we aimed to create evidence-based medical guidelines for the diagnosis, treatment, and prognosis of mechanical ocular trauma with NLP. Sixteen relevant recommendations for mechanical ocular trauma with NLP were obtained, and a consensus was reached. Each recommendation was explained in detail to guide the treatment of mechanical ocular trauma associated with NLP.


Asunto(s)
Lesiones Oculares Penetrantes , Lesiones Oculares Penetrantes/diagnóstico , Lesiones Oculares Penetrantes/cirugía , Humanos , Pronóstico , Estudios Retrospectivos , Agudeza Visual , Vitrectomía
14.
Sci Rep ; 11(1): 16958, 2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-34417509

RESUMEN

Rare oceanic diamonds are believed to have a mantle transition zone origin like super-deep continental diamonds. However, oceanic diamonds have a homogeneous and organic-like light carbon isotope signature (δ13C - 28 to - 20‰) instead of the extremely variable organic to lithospheric mantle signature of super-deep continental diamonds (δ13C - 25‰ to + 3.5‰). Here, we show that with rare exceptions, oceanic diamonds and the isotopically lighter cores of super-deep continental diamonds share a common organic δ13C composition reflecting carbon brought down to the transition zone by subduction, whereas the rims of such super-deep continental diamonds have the same δ13C as peridotitic diamonds from the lithospheric mantle. Like lithospheric continental diamonds, almost all the known occurrences of oceanic diamonds are linked to plume-induced large igneous provinces or ocean islands, suggesting a common connection to mantle plumes. We argue that mantle plumes bring the transition zone diamonds to shallower levels, where only those emplaced at the base of the continental lithosphere might grow rims with lithospheric mantle carbon isotope signatures.

15.
Food Addit Contam Part B Surveill ; 14(4): 264-270, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34236284

RESUMEN

Bamboo shoot is an indispensable vegetable in Southeastern China, so a survey of heavy metals in bamboo shoots is a relevant topic of interest. The present study sought to analyse the content of seven heavy metals (As, Cd, Cr, Cu, Mn, Pb and Zn) in six bamboo shoot species from Southeastern China. Percentages of 3.8% (Cd) and 8.9% (Pb) of the samples exceeded the maximum limits as established by the Chinese legislation. Further health risk assessment exhibited that the Cd intake contribution of these samples could not be negligible. The hazard index (HI) at average exposure was less than one. The average HI values in moso bamboo shoot were significantly higher than those of other bamboo shoot species. Overall, the results indicated that the intake of bamboo shoots is safe for consumers in Southeastern China.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , China , Monitoreo del Ambiente , Contaminación de Alimentos , Metales Pesados/análisis , Metales Pesados/toxicidad , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis , Verduras
16.
Front Pharmacol ; 12: 796590, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34992541

RESUMEN

Obesity is a worldwide epidemic metabolic disease. Gut microbiota dysbiosis and bile acids (BAs) metabolism disorder are closely related to obesity. Farnesoid X-activated receptor (FXR), served as a link between gut microbiota and BAs, is involved in maintaining metabolic homeostasis and regulating glucose and lipid metabolism. We previously reported that diammonium glycyrrhizinate (DG) could alter gut microbiota and prevent non-alcoholic fatty liver disease. However, it remains ambiguous how DG affects the gut microbiota to regulate host metabolism. In this present study, 16S rRNA Illumina NovaSeq and metabolomic analysis revealed that DG treatment suppressed microbes associated with bile-salt hydrolase (BSH) activity, which, in turn, increased the levels of taurine-conjugated BAs accompanied by inhibition of ileal FXR-FGF15 signaling. As a result, several obesity-related metabolism were improved, like lower serum glucose and insulin levels, increased insulin sensitivity, few hepatic steatosis and resistance to weight gain. Additionally, decreased level of serum lipopolysaccharide was observed, which contributed to a strengthened intestinal barrier. The effect of DG on weight loss was slightly enhanced in the antibiotics-treated obese mice. Collectively, the efficacy of DG in the treatment of obesity might depend on gut microbiota-conjugated BAs-FXR axis. Hence, it will provide a potential novel approach for the treatment of obesity.

17.
Acta Trop ; 216: 105752, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33188749

RESUMEN

Clonorchiasis is an important food-borne parasitic disease in China because of the popularity in ingesting raw freshwater fish. To explore the epidemiology and determinants of clonorchiasis in children, a cross-sectional survey was implemented in two middle schools in Qiyang county, Hunan province, in southeastern China. Questionnaire survey and fecal examination were implemented. Questionnaires were fed back by 627 students, while stool samples were collected from 557 students, out of which 545 ones also provided questionnaire information. The percentage of students ingesting raw freshwater fish was 40.5% (254/627), while the prevalence with Clonorchis sinensis infection was 18.9% (105/557). Such factors contributed significantly to the students' practice in eating raw freshwater fish including boys, fathers' eating raw freshwater fish, mothers' eating raw freshwater fish, and preparation of raw freshwater fish at home, with an adjusted odds ratio of 1.9 (95% confidence intervals (95% CI): 1.3-2.8), 3.9 (95% CI: 2.3-6.5), 3.0 (95% CI: 1.8-4.8) and 2.8 (95% CI: 1.8-4.5), correspondingly. Ingestion of raw freshwater fish, fathers' eating raw freshwater fish and preparation of raw freshwater fish at home were risk factors of C. sinensis infection in students, and the adjusted odds ratio was 3.2 (95% CI: 1.9-5.5), 2.1 (95% CI: 1.1-3.9) and 1.8 (95% CI: 1.0-3.2), respectively. Thus, clonorchiasis was endemic in the surveyed schools due to the ingestion of raw freshwater fish, which is influenced by family environment. Education should be implemented in schools to promote behavioral change of eating raw freshwater fish.


Asunto(s)
Clonorquiasis/epidemiología , Clonorchis sinensis , Peces/parasitología , Parasitología de Alimentos , Alimentos Crudos/parasitología , Adolescente , Animales , Niño , China/epidemiología , Estudios Transversales , Heces/parasitología , Femenino , Enfermedades Transmitidas por los Alimentos , Agua Dulce , Humanos , Masculino , Prevalencia , Factores de Riesgo , Instituciones Académicas , Estudiantes , Encuestas y Cuestionarios
18.
Nat Commun ; 11(1): 2937, 2020 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-32504004

RESUMEN

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

19.
Sci Rep ; 10(1): 9461, 2020 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-32528085

RESUMEN

Progressive mantle melting during the Earth's earliest evolution led to the formation of a depleted mantle and a continental crust enriched in highly incompatible elements. Re-enrichment of Earth's mantle can occur when continental crustal materials begin to founder into the mantle by either subduction or, to a lesser degree, by delamination processes, profoundly affecting the mantle's trace element and volatile compositions. Deciphering when mantle re-enrichment/refertilization became a global-scale process would reveal the onset of efficient mass transfer of crust to the mantle and potentially when plate tectonic processes became operative on a global-scale. Here we document the onset of mantle re-enrichment/refertilization by comparing the abundances of petrogenetically significant isotopic values and key ratios of highly incompatible elements compared to lithophile elements in Archean to Early-Proterozoic mantle-derived melts (i.e., basalts and komatiites). Basalts and komatiites both record a rapid-change in mantle chemistry around 3.2 billion years ago (Ga) signifying a fundamental change in Earth geodynamics. This rapid-change is recorded in Nd isotopes and in key trace element ratios that reflect a fundamental shift in the balance between fluid-mobile and incompatible elements (i.e., Ba/La, Ba/Nb, U/Nb, Pb/Nd and Pb/Ce) in basaltic and komatiitic rocks. These geochemical proxies display a significant increase in magnitude and variability after ~3.2 Ga. We hypothesize that rapid increases in mantle heterogeneity indicate the recycling of supracrustal materials back into Earth's mantle via subduction. Our new observations thus point to a ≥ 3.2 Ga onset of global subduction processes via plate tectonics.

20.
Artículo en Zh | MEDLINE | ID: mdl-20232625

RESUMEN

OBJECTIVE: To make an epidemiological investigation on clonorchiasis sinensis and relevant factors in the south of Hunan Province. METHODS: One village from each of Lengshuitan District and Qiyang County was selected for the survey from November to December in 2006. Stool samples from villagers were collected and examined by modified Kato-Katz method. Questionnairing was performed for relevant knowledge and attitude among residents. The infection rate in animal reservoirs and intermediate hosts were detected. RESULTS: A total of 586 cases with Clonorchis sinensis infection were found from 777 people with a prevalence of 75.4%. The average egg density was 451 eggs per gram (EPG) feces. Light, moderate and heavy infections occupied 85.5% (501/586), 14.0% (82/586), and 0.5% (3/586) respectively. Prevalence in males and females was 76.9% (316/411) and 73.8% (270/366) respectively with no significant difference (chi2 = 1.013, P > 0.05). Infections were found in all age groups, with the highest prevalence in the group of 70 to 79 years (85.7%, 30/35). By occupations, the prevalence was 82.5% (447/542) in peasants, 79.3% (42/53) in doctors, 73.7% (28/38) in teachers, and 73.5% (25/34) in local cadres. The infection rate was 17.4% (29/167) and 7.4% (2/27) in Parafossarulus seriatulus and Alocinma longicornis, and 69.2% (9/13) and 5.3% (1/19) in Carassius auratus and Cyprinus carpios respectively. Adult worms were found in all 3 dogs dissected. Over 80% inhabitants did not know that this disease can be acquired by eating raw fish. 95.6% (153/160) of the farmers and 56.7% (349/616) of the students had a history of eating raw fish. The water was contaminated with C. sinensis eggs by using untreated feces as fertilizer for farming and by scrubbing pail latrines in the ponds. CONCLUSION: The prevalence of clonorchiasis in human population is high in Lengshuitan District and Qiyang County of Hunan Province. Eating raw fish and using untreated feces as fertilizer are the most important epidemiological factors of the disease.


Asunto(s)
Clonorquiasis/epidemiología , Clonorquiasis/parasitología , Clonorchis sinensis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Niño , Preescolar , China/epidemiología , Perros , Heces/parasitología , Conducta Alimentaria , Femenino , Interacciones Huésped-Parásitos , Humanos , Lactante , Masculino , Persona de Mediana Edad , Recuento de Huevos de Parásitos , Encuestas y Cuestionarios , Adulto Joven
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