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1.
Bioinformatics ; 40(4)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38514400

RESUMEN

MOTIVATION: Large Language Models (LLMs) have the potential to revolutionize the field of Natural Language Processing, excelling not only in text generation and reasoning tasks but also in their ability for zero/few-shot learning, swiftly adapting to new tasks with minimal fine-tuning. LLMs have also demonstrated great promise in biomedical and healthcare applications. However, when it comes to Named Entity Recognition (NER), particularly within the biomedical domain, LLMs fall short of the effectiveness exhibited by fine-tuned domain-specific models. One key reason is that NER is typically conceptualized as a sequence labeling task, whereas LLMs are optimized for text generation and reasoning tasks. RESULTS: We developed an instruction-based learning paradigm that transforms biomedical NER from a sequence labeling task into a generation task. This paradigm is end-to-end and streamlines the training and evaluation process by automatically repurposing pre-existing biomedical NER datasets. We further developed BioNER-LLaMA using the proposed paradigm with LLaMA-7B as the foundational LLM. We conducted extensive testing on BioNER-LLaMA across three widely recognized biomedical NER datasets, consisting of entities related to diseases, chemicals, and genes. The results revealed that BioNER-LLaMA consistently achieved higher F1-scores ranging from 5% to 30% compared to the few-shot learning capabilities of GPT-4 on datasets with different biomedical entities. We show that a general-domain LLM can match the performance of rigorously fine-tuned PubMedBERT models and PMC-LLaMA, biomedical-specific language model. Our findings underscore the potential of our proposed paradigm in developing general-domain LLMs that can rival SOTA performances in multi-task, multi-domain scenarios in biomedical and health applications. AVAILABILITY AND IMPLEMENTATION: Datasets and other resources are available at https://github.com/BIDS-Xu-Lab/BioNER-LLaMA.


Asunto(s)
Camélidos del Nuevo Mundo , Aprendizaje Profundo , Animales , Lenguaje , Procesamiento de Lenguaje Natural
2.
Environ Sci Technol ; 58(20): 8643-8653, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38676641

RESUMEN

Antimicrobial nanomaterials frequently induce inflammatory reactions within lung tissues and prompt apoptosis in lung cells, yielding a paradox due to the inherent anti-inflammatory character of apoptosis. This paradox accentuates the elusive nature of the signaling cascade underlying nanoparticle (NP)-induced pulmonary inflammation. In this study, we unveil the pivotal role of nano-microflora interactions, serving as the crucial instigator in the signaling axis of NP-induced lung inflammation. Employing pulmonary microflora-deficient mice, we provide compelling evidence that a representative antimicrobial nanomaterial, silver (Ag) NPs, triggers substantial motility impairment, disrupts quorum sensing, and incites DNA leakage from pulmonary microflora. Subsequently, the liberated DNA molecules recruit caspase-1, precipitating the release of proinflammatory cytokines and activating N-terminal gasdermin D (GSDMD) to initiate pyroptosis in macrophages. This pyroptotic cascade culminates in the emergence of severe pulmonary inflammation. Our exploration establishes a comprehensive mechanistic axis that interlinks the antimicrobial activity of Ag NPs, perturbations in pulmonary microflora, bacterial DNA release, macrophage pyroptosis, and consequent lung inflammation, which helps to gain an in-depth understanding of the toxic effects triggered by environmental NPs.


Asunto(s)
Neumonía , Piroptosis , Piroptosis/efectos de los fármacos , Ratones , Animales , Neumonía/inducido químicamente , Neumonía/patología , Plata/toxicidad , Nanopartículas del Metal/toxicidad , Macrófagos/efectos de los fármacos , Inflamación
3.
J Am Chem Soc ; 145(5): 3108-3120, 2023 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-36700857

RESUMEN

Nicotinamide adenine dinucleotide (NAD) is a critical regulator of metabolic networks, and declining levels of its oxidized form, NAD+, are closely associated with numerous diseases. While supplementing cells with precursors needed for NAD+ synthesis has shown poor efficacy in combatting NAD+ decline, an alternative strategy is the development of synthetic materials that catalyze the oxidation of NADH into NAD+, thereby taking over the natural role of the NADH oxidase (NOX) present in bacteria. Herein, we discovered that metal-nitrogen-doped graphene (MNGR) materials can catalyze the oxidation of NADH into NAD+. Among MNGR materials with different transition metals, Fe-, Co-, and Cu-NGR displayed strong catalytic activity combined with >80% conversion of NADH into NAD+, similar specificity to NOX for abstracting hydrogen from the pyridine ring of nicotinamide, and higher selectivity than 51 other nanomaterials. The NOX-like activity of FeNGR functioned well in diverse cell lines. As a proof of concept of the in vivo application, we showed that FeNGR could specifically target the liver and remedy the metabolic flux anomaly in obesity mice with NAD+-deficient cells. Overall, our study provides a distinct insight for exploration of drug candidates by design of synthetic materials to mimic the functions of unique enzymes (e.g., NOX) in bacteria.


Asunto(s)
Grafito , NAD , Ratones , Animales , NAD/metabolismo , Oxidación-Reducción , Mamíferos/metabolismo , Bacterias/metabolismo , Suplementos Dietéticos
4.
Anal Chem ; 95(14): 6009-6019, 2023 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-37005435

RESUMEN

Fine particulates (FPs) are a major class of airborne pollutants. In mammals, FPs may reach the alveoli through the respiratory system, cross the air-blood barrier, spread into other organs, and induce hazardous effects. Although birds have much higher respiratory risks to FPs than mammals, the biological fate of inhaled FPs in birds has rarely been explored. Herein, we attempted to disclose the key properties that dictate the lung penetration of nanoparticles (NPs) by visualizing a library of 27 fluorescent nanoparticles (FNPs) in chicken embryos. The FNP library was prepared by combinational chemistry to tune their compositions, morphologies, sizes, and surface charges. These NPs were injected into the lungs of chicken embryos for dynamic imaging of their distributions by IVIS Spectrum. FNPs with diameters <16 nm could cross the air-blood barrier in 20 min, spread into the blood, and accumulate in the yolk sac. In contrast, large FNPs (>30 nm) were mainly retained in the lungs and rarely detected in other tissues/organs. In addition to size, surface charge was the secondary determinant for NPs to cross the air-blood barrier. Compared to cationic and anionic particles, neutrally charged FNPs showed the fastest lung penetration. A predictive model was therefore developed to rank the lung penetration capability of FNPs by in silico analysis. The in silico predictions could be well validated in chicks by oropharyngeal exposure to six FNPs. Overall, our study discovered the key properties of NPs that are responsible for their lung penetration and established a predictive model that will greatly facilitate respiratory risk assessments of nanoproducts.


Asunto(s)
Pollos , Nanopartículas , Embrión de Pollo , Animales , Barrera Alveolocapilar , Nanopartículas/química , Pulmón , Colorantes , Tamaño de la Partícula , Mamíferos
5.
Virus Genes ; 59(2): 195-203, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36253516

RESUMEN

Parvoviruses possess a single-stranded DNA genome of about 5 kb, which contains two open reading frames (ORFs), one encoding nonstructural (NS) proteins, the other capsid proteins. The NS1 protein contains an N-terminal origin-binding domain, a helicase domain, and a C-terminal transactive domain, and is essential for effective viral replication and production of infectious virus. We first summarize the developments in the structure of NS1 protein, including the original binding domain and the helicase domain. We discuss the role of different DNA substrates in the oligomerization of these two domains of NS1. During the parvovirus life cycle, the NS1 protein is closely related to the viral gene expression, viral replication, and infection. We provide the current understanding of the impact of parvovirus NS1 protein mutations on its biological properties. Overall, in this review, we focus on the structure and function of the parvoviral NS1 protein.


Asunto(s)
Replicación del ADN , Proteínas , Proteínas/metabolismo , Replicación Viral/genética , Unión Proteica , Mutación , Proteínas no Estructurales Virales/metabolismo
6.
Virus Genes ; 59(1): 100-108, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36272032

RESUMEN

Mink enteritis virus (MEV) NS1 is a multidomain and multifunctional protein containing origin binding, helicase, and transactivation domains. In particular, parvoviral NS1 proteins are transactivators of the viral capsid protein promoter although the manner by which they exert these transactivation effects remained unclear. In this study, the region of the transactivation domain of the NS1 C-terminal was found located at aa 557 ~ 668 and any deletion within this region reduced the transactivation activity. A dominant negative mutation of the 63 aa deletion in the C-terminal of NS1 protein resulted in loss of ability to activate P38 and VP2-5'UTR in a dual-luciferase reporter assay system, a VP2 protein expression system, and within the whole MEV genome, independent of downstream genes. Additionally, a full-length MEV clone deficient in its NS1 C-terminal failed to rescue the virus, possibly due to the loss of integrity of DNA sequences interacting with NS1 protein, and expression of VP2 was also inhibited even when normal NS1 protein was supplied in trans.


Asunto(s)
Virus de la Enteritis del Visón , Animales , Activación Transcripcional , Virus de la Enteritis del Visón/genética , Virus de la Enteritis del Visón/metabolismo , Regiones Promotoras Genéticas , Secuencia de Bases , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo , Unión Proteica , Visón/genética
7.
Virus Genes ; 59(4): 572-581, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37103648

RESUMEN

Newcastle disease (ND) is the most important infectious disease in poultry, which is caused by avian orthoavulavirus type 1 (AOAV-1), previously known as Newcastle disease virus (NDV). In this study, an NDV strain SD19 (GenBank accession number OP797800) was isolated, and phylogenetic analysis suggested the virus belongs to the class II genotype VII. After generating wild-type rescued SD19 (rSD19), the attenuating strain (raSD19) was generated by mutating the F protein cleavage site. To explore the potential role of the transmembrane protease, serine S1 member 2 (TMPRSS2), the TMPRSS2 gene was inserted into the region between the P and M genes of raSD19 to generate raSD19-TMPRSS2. Besides, the coding sequence of the enhanced green fluorescent protein (EGFP) gene was inserted in the same region as a control (rSD19-EGFP and raSD19-EGFP). The Western blot, indirect immunofluorescence assay (IFA), and real-time quantitative PCR were employed to determine the replication activity of these constructs. The results reveal that all the rescued viruses can replicate in chicken embryo fibroblast (DF-1) cells; however, the proliferation of raSD19 and raSD19-EGFP needs additional trypsin. We next evaluated the virulence of these constructs, and our results reveal that the SD19, rSD19, and rSD19-EGFP are velogenic; the raSD19 and raSD19-EGFP are lentogenic; and the raSD19-TMPRSS2 are mesogenic. Moreover, due to the enzymatic hydrolysis of serine protease, the raSD19-TMPRSS2 can support itself to proliferate in the DF-1 cells without adding exogenous trypsin. These results may provide a new method for the NDV cell culture and contribute to ND's vaccine development.


Asunto(s)
Enfermedad de Newcastle , Enfermedades de las Aves de Corral , Vacunas Virales , Animales , Embrión de Pollo , Virus de la Enfermedad de Newcastle , Tripsina/genética , Filogenia , Genética Inversa , Pollos , Genoma Viral/genética , Genotipo , Tropismo , Vacunas Virales/genética
8.
J Biomed Inform ; 146: 104482, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37652343

RESUMEN

OBJECTIVE: Computer-assisted diagnostic and prognostic systems of the future should be capable of simultaneously processing multimodal data. Multimodal deep learning (MDL), which involves the integration of multiple sources of data, such as images and text, has the potential to revolutionize the analysis and interpretation of biomedical data. However, it only caught researchers' attention recently. To this end, there is a critical need to conduct a systematic review on this topic, identify the limitations of current work, and explore future directions. METHODS: In this scoping review, we aim to provide a comprehensive overview of the current state of the field and identify key concepts, types of studies, and research gaps with a focus on biomedical images and texts joint learning, mainly because these two were the most commonly available data types in MDL research. RESULT: This study reviewed the current uses of multimodal deep learning on five tasks: (1) Report generation, (2) Visual question answering, (3) Cross-modal retrieval, (4) Computer-aided diagnosis, and (5) Semantic segmentation. CONCLUSION: Our results highlight the diverse applications and potential of MDL and suggest directions for future research in the field. We hope our review will facilitate the collaboration of natural language processing (NLP) and medical imaging communities and support the next generation of decision-making and computer-assisted diagnostic system development.


Asunto(s)
Aprendizaje Profundo , Diagnóstico por Imagen , Semántica , Procesamiento de Lenguaje Natural , Diagnóstico por Computador
9.
Echocardiography ; 40(4): 306-317, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36859694

RESUMEN

BACKGROUND: Literature suggests that left ventricular global longitudinal strain (LV-GLS) on speckle echocardiography has the potential to predict cardiotoxicity amongst breast cancer patients receiving chemotherapy such as anthracycline, taxane, cyclophosphamide, and trastuzumab. Our study aimed to collect evidence for the prognostic value of LV-GLS for predicting chemotherapy-induced cardiotoxicity in breast cancer patients. METHODS: A detailed search of the PubMed, Google Scholar, Cochrane Library, and Scopus databases was conducted for published articles up to August 31, 2022. In our meta-analysis, we looked at 13 studies with a total of 1007 breast cancer patients getting chemotherapy that looked at the predictive value of GLS. RESULTS: Absolute GLS change during treatment showed a pooled sensitivity of 84% (95% CI 74% to 91%) and a pooled specificity of 77% (95% CI 68% to 84%).  For a relative change in GLS, we observed a pooled sensitivity of 76% (95% CI 56% to 89%) and a pooled specificity of 83% (95% CI 73% to 90%).  For an absolute change in GLS, we observed a positive likelihood ratio (LR), and the negative LR was 4 and .21. Summary receiver operating characteristics curve with prediction and confidence intervals represents a promising summary area under the curve (sAUC) of .88, 95% CI ranges from .85 to .91 for absolute change in GLS, as well as for relative change (sAUC, .87, 95% CI .84 to .90). CONCLUSION: Our results demonstrated an estimation of LV-GLS after the beginning of required chemotherapy, including anthracyclines and trastuzumab, had a promising prognostic value for predicting the likelihood of cancer therapeutics-related cardiac dysfunction. To confirm our findings, well-designed prospective adequately powered diagnostic randomised trials are necessary.


Asunto(s)
Neoplasias de la Mama , Disfunción Ventricular Izquierda , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Cardiotoxicidad/diagnóstico por imagen , Cardiotoxicidad/etiología , Pronóstico , Estudios Prospectivos , Tensión Longitudinal Global , Disfunción Ventricular Izquierda/inducido químicamente , Disfunción Ventricular Izquierda/diagnóstico por imagen , Ecocardiografía/métodos , Trastuzumab/efectos adversos , Antibióticos Antineoplásicos/efectos adversos , Función Ventricular Izquierda , Volumen Sistólico
10.
Biochem Biophys Res Commun ; 604: 8-13, 2022 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-35279444

RESUMEN

Feline calicivirus (FCV) is an important and highly prevalent pathogen of cats that causes acute infectious respiratory disease. Here it is shown in vitro that FCV induces the production of cyclooxygenase-2 (COX-2) through the MEK1-ERK1/2 signaling pathway. Screening of FCV proteins revealed that FCV non-structural protein VPg enhanced COX-2 mRNA expression and protein production in CRFK cells in a concentration-dependent manner. Regions 24-54aa and 84-111aa in FCV VPg were essential for up-regulation. In vivo, COX-2 and IL-6 production caused by FCV infection of kittens was significantly suppressed by the MEK1 inhibitor AZD6244 (selumetinib) and lung inflammation and injury were practically eliminated, with body temperature being returned to normal. AZD6244 may therefore find application as an effective therapeutic agent for the treatment of FCV infection.


Asunto(s)
Infecciones por Caliciviridae , Calicivirus Felino , Neumonía , Animales , Bencimidazoles , Infecciones por Caliciviridae/tratamiento farmacológico , Infecciones por Caliciviridae/metabolismo , Infecciones por Caliciviridae/veterinaria , Gatos , Ciclooxigenasa 2/metabolismo , Femenino , Sistema de Señalización de MAP Quinasas
11.
Neurol Sci ; 43(5): 3113-3120, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34817725

RESUMEN

BACKGROUND: Previous studies have shown that uric acid (UA) is a powerful water-soluble antioxidant and free radical scavenger for humans. However, the relationship between serum uric acid (SUA) and hemorrhagic transformation (HT) is still controversial. To address this challenge, we aimed to explore the association between serum UA and HT in patients with acute ischemic stroke (AIS) after intravenous thrombolysis (IVT). METHODS: A retrospective analysis was conducted in patients with anterior circulation AIS who underwent IVT at Affiliated Hospital of Qingdao University from 2016 to 2021. HT was evaluated by CT or MRI within 7 days after admission. Baseline demographic, clinical, and laboratory data were compared between the HT and non-HT groups, and between different types of HT groups which were documented according to the European Cooperative Acute Stroke Study III Classification (ECASS III). RESULTS: A total of 727 AIS patients were enrolled, including 112 patients who experienced HT (HT group) and 615 patients who did not experience HT (non-HT group). Patients with HT had significantly lower UA levels compared to those without HT (253.65 ± 97.75 vs 315.97 ± 96.42, p < 0.001); however, there was no significant difference for UA levels in different types of HT (p = 0.907). After adjusting confounders, patients in the fourth UA quartile showed a significant decrease in HT compared with those in the first quartile (OR 0.266, 95% CI 0.107-0.661, p = 0.006). The best cutoff value was identified as 218.5 µmol/L after analysis. CONCLUSIONS: These findings suggest that low levels of UA may be associated with HT after IVT.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Isquemia Encefálica/complicaciones , Humanos , Estudios Retrospectivos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/tratamiento farmacológico , Terapia Trombolítica/efectos adversos , Ácido Úrico
12.
J Environ Sci (China) ; 114: 444-453, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35459507

RESUMEN

This study attempts to identify the dominant transport pathways, potential source areas, and their seasonal variation at sites with high inorganic nitrogen (IN) wet deposition flux in southern China. This is a long-term study (2010-2017) based on continuous deposition measurements at the Guangzhou urban site (GZ) and the Dinghushan Natural Reserve site (DHS) located in the Pearl River Delta (PRD) region. A dataset on monthly IN concentration in precipitation and wet deposition flux were provided. The average annual fluxes measured at both sites (GZ: 33.04±9.52, DHS: 20.52±10.22 kg N/(ha∙year)) were higher, while the ratios of reduced to oxidized N (GZ: 1.19±0.77, DHS: 1.25±0.84) were lower compared with the national mean level and the previous reported level throughout the PRD region. The dominant pathways were not always consistent with the highest proportional trajectory clusters. The transport pathways contributing most of deposition were identified in the north and north-northeast in the dry season and in the east-southeast, east, and south-southwest in the wet season. A weighted potential source contribution function (WPSCF) value >0.3 was determined reasonably to define the potential source area. Emission within the PRD region contributed the majority (≥95% at both sites) of the IN deposition in the wet season, while the contribution outside the region increased significantly in the dry season (GZ: 27.86%, DHS: 95.26%). Our results could help create more effective policy to control precursor emissions for IN fluxes, enabling reduction of the ecological risks due to excessive nitrogen.


Asunto(s)
Contaminantes Atmosféricos , Nitrógeno , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente/métodos , Nitrógeno/análisis , Estaciones del Año
13.
Part Fibre Toxicol ; 18(1): 17, 2021 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-33902647

RESUMEN

BACKGROUND: Disruption of microbiota balance may result in severe diseases in animals and phytotoxicity in plants. While substantial concerns have been raised on engineered nanomaterial (ENM) induced hazard effects (e.g., lung inflammation), exploration of the impacts of ENMs on microbiota balance holds great implications. RESULTS: This study found that rare earth oxide nanoparticles (REOs) among 19 ENMs showed severe toxicity in Gram-negative (G-) bacteria, but negligible effects in Gram-positive (G+) bacteria. This distinct cytotoxicity was disclosed to associate with the different molecular initiating events of REOs in G- and G+ strains. La2O3 as a representative REOs was demonstrated to transform into LaPO4 on G- cell membranes and induce 8.3% dephosphorylation of phospholipids. Molecular dynamics simulations revealed the dephosphorylation induced more than 2-fold increments of phospholipid diffusion constant and an unordered configuration in membranes, eliciting the increments of membrane fluidity and permeability. Notably, the ratios of G-/G+ reduced from 1.56 to 1.10 in bronchoalveolar lavage fluid from the mice with La2O3 exposure. Finally, we demonstrated that both IL-6 and neutrophil cells showed strong correlations with G-/G+ ratios, evidenced by their correlation coefficients with 0.83 and 0.92, respectively. CONCLUSIONS: This study deciphered the distinct toxic mechanisms of La2O3 as a representative REO in G- and G+ bacteria and disclosed that La2O3-induced membrane damages of G- cells cumulated into pulmonary microbiota imbalance exhibiting synergistic pulmonary toxicity. Overall, these findings offered new insights to understand the hazard effects induced by REOs.


Asunto(s)
Metales de Tierras Raras , Microbiota , Nanopartículas , Animales , Biotransformación , Ratones , Óxidos
14.
J Am Chem Soc ; 142(46): 19602-19610, 2020 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-33108194

RESUMEN

NADPH oxidase (NOX) as a transmembrane enzyme complex controls the generation of superoxide that plays important roles in immune signaling pathway. NOX inactivation may elicit immunodeficiency and cause chronic granulomatous disease (CGD). Biocompatible synthetic materials with NOX-like activities would therefore be interesting as curative and/or preventive approaches in case of NOX deficiency. Herein, we synthesized a Fe-N doped graphene (FeNGR) nanomaterial that could mimic the activity of NOX by efficiently catalyzing the conversion of NADPH into NADP+ and triggering the generation of oxygen radicals. The resulting FeNGR nanozyme had similar cellular distribution to NOX and is able to mimic the enzyme function in NOX-deficient cells by catalyzing the generation of superoxide and retrieving the immune activity, evidenced by TNF-α, IL-1ß, and IL-6 production in response to Alum exposure. Overall, our study discovered a synthetic material (FeNGR) to mimic NOX and demonstrated its biological function in immune activation of NOX-deficient cells.


Asunto(s)
Materiales Biomiméticos/química , Grafito/química , Hierro/química , NADPH Oxidasas/química , Nitrógeno/química , Materiales Biomiméticos/metabolismo , Colorantes Fluorescentes/química , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Modelos Moleculares , NADP/metabolismo , NADPH Oxidasas/metabolismo , Oxidación-Reducción , Peroxidasa/metabolismo , Especies Reactivas de Oxígeno/química , Transducción de Señal , Superóxidos/química , Superóxidos/metabolismo , Células THP-1 , Factor de Necrosis Tumoral alfa/metabolismo
15.
Environ Res ; 188: 109887, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32846653

RESUMEN

Biochar has been recognized as a sustainable platform for developing functional materials including catalysts. This work demonstrated a method of converting biochar to sulfonated solid-acid catalysts, and the effectiveness of the catalysts for spiramycin hydrolysis was examined. Two biochar samples (H and X) were sulfonated with three reagents (concentrated H2SO4, ClSO3H and p-toluenesulfonic acid (TsOH)) under hydrothermal, simple heating, ambient temperature, and CHCl3-assisted treatments. The effect of elemental compositions and structural characteristics of the feeding materials (H and X) on the acidic properties of the sulfonated biochars were investigated. The results showed that the sulfonation ability of the three reagents was in the order of ClSO3H > H2SO4 > TsOH, while hydrothermal treatment provided the highest total acidity, and largest amount of acidic groups (e.g., SO3H, COOH and Ar-OH). Biochar X with higher O/C and N contents, and less graphitic features showed superior acidic properties than biochar H under all the employed treatments. The hydrolytic efficiencies of the sulfonated biochars under 200 W of microwave irradiation increased with increasing total acidity, and the amount of SO3H and COOH groups. After sulfonation, the O/C of biochars increased, while H/C decreased, and the aromatic and graphitic features did not change. The electromagnetic energy absorbed by the sulfonated biochars did not notably contribute to spiramycin hydrolysis. Thus, this work demonstrated an effective and promising method for maneuvering biochar-based functional solid-acid catalysts for antibiotic remediation in contaminated water.


Asunto(s)
Espiramicina , Catálisis , Carbón Orgánico , Hidrólisis
16.
BMC Public Health ; 20(1): 1472, 2020 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-32993592

RESUMEN

BACKGROUND: Urban-rural disparity in mortality at older ages is well documented in China. However, surprisingly few studies have systemically investigated factors that contribute to such disparity. This study examined the extent to which individual-level socioeconomic conditions, family/social support, health behaviors, and baseline health status contributed to the urban-rural difference in mortality among older adults in China. METHODS: This research used the five waves of the Chinese Longitudinal Healthy Longevity Survey from 2002 to 2014, a nationally representative sample of older adults aged 65 years or older in China (n = 28,235). A series of hazard regression models by gender and age group examined the association between urban-rural residence and mortality and how this association was modified by a wide range of individual-level factors. RESULTS: Older adults in urban areas had 11% (relative hazard ratio (HR) = 0.89, p < 0.01) lower risks of mortality than their rural counterparts when only demographic factors were taken into account. Further adjustments for family/social support, health behaviors, and health-related factors individually or jointly had a limited influence on the mortality differential between urban and rural older adults (HRs = 0.89-0.92, p < 0.05 to p < 0.01). However, we found no urban-rural difference in mortality (HR = 0.97, p > 0.10) after adjusting for individual socioeconomic factors. Similar results were found in women and men, and among the young-old and the oldest-old populations. CONCLUSIONS: The urban-rural disparity in mortality among older adults in China was largely attributable to differences in individual socioeconomic resources (i.e., education, income, and access to healthcare) regardless of gender and age group.


Asunto(s)
Conductas Relacionadas con la Salud , Estado de Salud , Renta/estadística & datos numéricos , Población Rural/estadística & datos numéricos , Población Urbana/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , China/epidemiología , Femenino , Humanos , Longevidad , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Riesgo , Percepción Social , Apoyo Social , Factores Socioeconómicos , Adulto Joven
17.
Angew Chem Int Ed Engl ; 59(50): 22431-22435, 2020 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-32794297

RESUMEN

The application of NIR-II emitters for gastrointestinal (GI) tract imaging remains challenging due to fluorescence quenching in the digestive microenvironment. Herein, we report that red-shifting of the fluorescence emission of Au nanoclusters (AuNCs) into NIR-II region with improved quantum yields (QY) could be achieved by engineering a protein corona structure consisting of a ribonuclease-A (RNase-A) on the particle surfaces. RNase-A-encapsulated AuNCs (RNase-A@AuNCs) displayed emissions at 1050 nm with a 1.9 % QY. Compared to rare earth and silver-based NIR-II emitters, RNase-A@AuNCs had excellent biocompatibility, showing >50-fold higher sensitivity in GI tract, and migrated homogenously during gastrointestinal peristalsis to allow visualization of the detailed structures of the GI tract. RNase-A@AuNCs could successfully examine intestinal tumor mice from healthy mice, indicating a potential utility for early diagnosis of intestinal tumors.


Asunto(s)
Tracto Gastrointestinal/diagnóstico por imagen , Oro/química , Neoplasias Intestinales/diagnóstico por imagen , Nanopartículas del Metal/química , Corona de Proteínas/química , Ingeniería de Proteínas , Animales , Rayos Infrarrojos , Ratones , Estructura Molecular
18.
Artículo en Zh | MEDLINE | ID: mdl-30148291

RESUMEN

Objective: To investigate the transportation of intracellular and extracellular K(+), Ca(2+), Na(+) and Mg(2+) under the function of Cryptosporidium andersoni ATP-binding cassette (CaABC) 1 gene. Methods: CaABC1 gene was amplified by PCR using specifically designed primers. The eukaryotic expression plasmid pEGFP-C1-CaABC1 was constructed, and transfected into mouse intestinal epithelial cells via liposome transfection. The blank (with no transfection) and control groups (transfected with empty plasmid pEGFP-C1) were also set. Changes in intracellular and extracellular K(+), Ca(2+), Na(+) and Mg(2+) concentrations were examined by the ion concentration assay kit. Results: PCR amplification resulted in a 544 bp product. The recombinant plasmid pEGFP-C1-CaABC1 was successfully constructed. Green fluorescence was seen in the control and transfected groups, but not in the blank group. The concentrations of K(+), Ca(2+), Na(+) and Mg(2+) in intracellular fluid were (5.51 ± 0.51), (1.98 ± 0.06), (108.33 ± 1.33) and (0.93 ± 0.03) mmol/L in the blank group; (6.25 ± 0.70), (1.90 ± 0.13), (107.73 ± 1.79) and (0.87 ± 0.05) mmol/L in the control group; and (14.84 ± 0.90), (3.40 ± 0.14), (127.64 ± 1.49) and (1.72 ± 0.20) mmol/L in the transfected group. The concentrations of K+, Ca2+, Na+ and Mg2+ in extracellular fluid were (12.72 ± 0.83), (3.72 ± 0.03), (116.83 ± 1.04) and (2.02 ± 0.18) mmol/L in the blank group; (10.11 ± 0.90), (3.58 ± 0.06), (115.89 ± 1.86) and (1.71 ± 0.41) mmol/L in the control group; and (5.77 ± 0.21), (1.29 ± 0.18), (96.21 ± 1.19) and (0.64 ± 0.02) mmol/L in the transfected group. There were significant differences in K+, Ca2+ and Mg2+ concentrations between the transfected group and the control group. Conclusion: CaABC1 participates in the transportation of K+, Ca2+ and Mg2+.


Asunto(s)
Cryptosporidium , Transfección , Transportador 1 de Casete de Unión a ATP , Adenosina Trifosfato , Animales , Citoplasma , Células Epiteliales , Ratones , Plásmidos
19.
J Sep Sci ; 38(11): 1933-41, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25763770

RESUMEN

D4020 resin offered the best dynamic adsorption and desorption capacity for total flavonoids based on the research results from ten kinds of macroporous resin. A column packed with D4020 resin was used to optimize the separation of total flavonoids from Flaveria bidentis (L.) Kuntze extracts. The content of flavonoids in the product was increased from 4.3 to 30.1% with a recovery yield of 90%. After the treatment with gradient elution on D4020 resin, the contents of isorhamnetin 3-sulfate and astragalin were increased from 0.49 to 8.70% with a recovery yield of 74.1% and 1.16 to 30.8%, with a recovery yield of 92.2%, respectively. Further purification was carried out by one-run high-speed countercurrent chromatography yielding 4.5 mg of isorhamnetin 3-sulfate at a high purity of 96.48% and yielding 24.4 mg of astragalin at a high purity of over 98.46%.


Asunto(s)
Distribución en Contracorriente/métodos , Flaveria/química , Quempferoles/aislamiento & purificación , Quercetina/análogos & derivados , Adsorción , Cromatografía Líquida de Alta Presión , Concentración de Iones de Hidrógeno , Porosidad , Quercetina/aislamiento & purificación
20.
Korean J Parasitol ; 53(3): 335-9, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26174828

RESUMEN

Cryptosporidium andersoni ATP-binding cassette (CaABC) is an important membrane protein involved in substrate transport across the membrane. In this research, the nucleotide binding domain (NBD) of CaABC gene was amplified by PCR, and the eukaryotic expression vector of pEGFP-C1-CaNBD was reconstructed. Then, the recombinant plasmid of pEGFP-C1-CaNBD was transformed into the mouse intestinal epithelial cells (IECs) to study the iron transportation function of CaABC. The results indicated that NBD region of CaABC gene can significantly elevate the transport efficiency of Ca(2+), Mg(2+), K(+), and HCO3 (-) in IECs (P<0.05). The significance of this study is to find the ATPase inhibitors for NBD region of CaABC gene and to inhibit ATP binding and nutrient transport of CaABC transporter. Thus, C. andersoni will be killed by inhibition of nutrient uptake. This will open up a new way for treatment of cryptosporidiosis.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/química , Transportadoras de Casetes de Unión a ATP/genética , Clonación Molecular , Cryptosporidium/metabolismo , Proteínas Protozoarias/química , Proteínas Protozoarias/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Adenosina Trifosfato/metabolismo , Secuencia de Aminoácidos , Animales , Calcio/metabolismo , Criptosporidiosis/parasitología , Cryptosporidium/química , Cryptosporidium/genética , Humanos , Hierro/metabolismo , Ratones , Datos de Secuencia Molecular , Estructura Terciaria de Proteína , Proteínas Protozoarias/metabolismo , Alineación de Secuencia
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