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1.
Lancet ; 403(10445): 2720-2731, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38824941

RESUMEN

BACKGROUND: Anti-PD-1 therapy and chemotherapy is a recommended first-line treatment for recurrent or metastatic nasopharyngeal carcinoma, but the role of PD-1 blockade remains unknown in patients with locoregionally advanced nasopharyngeal carcinoma. We assessed the addition of sintilimab, a PD-1 inhibitor, to standard chemoradiotherapy in this patient population. METHODS: This multicentre, open-label, parallel-group, randomised, controlled, phase 3 trial was conducted at nine hospitals in China. Adults aged 18-65 years with newly diagnosed high-risk non-metastatic stage III-IVa locoregionally advanced nasopharyngeal carcinoma (excluding T3-4N0 and T3N1) were eligible. Patients were randomly assigned (1:1) using blocks of four to receive gemcitabine and cisplatin induction chemotherapy followed by concurrent cisplatin radiotherapy (standard therapy group) or standard therapy with 200 mg sintilimab intravenously once every 3 weeks for 12 cycles (comprising three induction, three concurrent, and six adjuvant cycles to radiotherapy; sintilimab group). The primary endpoint was event-free survival from randomisation to disease recurrence (locoregional or distant) or death from any cause in the intention-to-treat population. Secondary endpoints included adverse events. This trial is registered with ClinicalTrials.gov (NCT03700476) and is now completed; follow-up is ongoing. FINDINGS: Between Dec 21, 2018, and March 31, 2020, 425 patients were enrolled and randomly assigned to the sintilimab (n=210) or standard therapy groups (n=215). At median follow-up of 41·9 months (IQR 38·0-44·8; 389 alive at primary data cutoff [Feb 28, 2023] and 366 [94%] had at least 36 months of follow-up), event-free survival was higher in the sintilimab group compared with the standard therapy group (36-month rates 86% [95% CI 81-90] vs 76% [70-81]; stratified hazard ratio 0·59 [0·38-0·92]; p=0·019). Grade 3-4 adverse events occurred in 155 (74%) in the sintilimab group versus 140 (65%) in the standard therapy group, with the most common being stomatitis (68 [33%] vs 64 [30%]), leukopenia (54 [26%] vs 48 [22%]), and neutropenia (50 [24%] vs 46 [21%]). Two (1%) patients died in the sintilimab group (both considered to be immune-related) and one (<1%) in the standard therapy group. Grade 3-4 immune-related adverse events occurred in 20 (10%) patients in the sintilimab group. INTERPRETATION: Addition of sintilimab to chemoradiotherapy improved event-free survival, albeit with higher but manageable adverse events. Longer follow-up is necessary to determine whether this regimen can be considered as the standard of care for patients with high-risk locoregionally advanced nasopharyngeal carcinoma. FUNDING: National Natural Science Foundation of China, Key-Area Research and Development Program of Guangdong Province, Natural Science Foundation of Guangdong Province, Overseas Expertise Introduction Project for Discipline Innovation, Guangzhou Municipal Health Commission, and Cancer Innovative Research Program of Sun Yat-sen University Cancer Center. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Quimioradioterapia , Quimioterapia de Inducción , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Persona de Mediana Edad , Masculino , Femenino , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/tratamiento farmacológico , Adulto , China/epidemiología , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/terapia , Quimioradioterapia/métodos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anciano , Cisplatino/uso terapéutico , Cisplatino/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Gemcitabina , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Desoxicitidina/administración & dosificación , Adulto Joven , Adolescente , Supervivencia sin Progresión
2.
Anal Chem ; 96(1): 437-445, 2024 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-38150621

RESUMEN

Damage of reactive oxygen species to various molecules such as DNA has been related to many chronic and degenerative human diseases, aging, and even cancer. 8-Oxo-7,8-dihydroguanine (OG), the most significant oxidation product of guanine (G), has become a biomarker of oxidative stress as well as gene regulation. The positive effect of OG in activating transcription and the negative effect in inducing mutation are a double-edged sword; thus, site-specific quantification is helpful to quickly reveal the functional mechanism of OG at hotspots. Due to the possible biological effects of OG at extremely low abundance in the genome, the monitoring of OG is vulnerable to signal interference from a large amount of G. Herein, based on rolling circle amplification-induced G-triplex formation and Thioflavin T fluorescence enhancement, an ultrasensitive strategy for locus-specific OG quantification was constructed. Owing to the difference in the hydrogen-bonding pattern between OG and G, the nonspecific background signal of G sites was completely suppressed through enzymatic ligation of DNA probes and the triggered specificity of rolling circle amplification. After the signal amplification strategy was optimized, the high detection sensitivity of OG sites with an ultralow detection limit of 0.18 amol was achieved. Under the interference of G sites, as little as 0.05% of OG-containing DNA was first distinguished. This method was further used for qualitative and quantitative monitoring of locus-specific OG in genomic DNA under oxidative stress and identification of key OG sites with biological function.


Asunto(s)
ADN , Guanina , Humanos , ADN/genética , Estrés Oxidativo , Especies Reactivas de Oxígeno , Técnicas de Amplificación de Ácido Nucleico
3.
Anal Chem ; 96(21): 8458-8466, 2024 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-38710075

RESUMEN

G-triplexes are G-rich oligonucleotides composed of three G-tracts and have absorbed much attention due to their potential biological functions and attractive performance in biosensing. Through the optimization of loop compositions, DNA lengths, and 5'-flanking bases of G-rich sequences, a new stable G-triplex sequence with 14 bases (G3-F15) was discovered to dramatically activate the fluorescence of Thioflavin T (ThT), a water-soluble fluorogenic dye. The fluorescence enhancement of ThT after binding with G3-F15 reached 3200 times, which was the strongest one by far among all of the G-rich sequences. The conformations of G3-F15 and G3-F15/ThT were studied by circular dichroism. The thermal stability measurements indicated that G3-F15 was a highly stable G-triplex structure. The conformations of G3-F15 and G3-F15/ThT in the presence of different metal cations were studied thoroughly by fluorescent spectroscopy, circular dichroism, and nuclear magnetic resonance. Furthermore, using the G3-F15/ThT complex as a fluorescent probe, a robust and simple turn-on fluorescent sensor for uracil-DNA glycosylase activity was developed. This study proposes a new systematic strategy to explore new functional G-rich sequences and their ligands, which will promote their applications in diagnosis, therapy, and biosensing.


Asunto(s)
Benzotiazoles , ADN , Fluorescencia , Uracil-ADN Glicosidasa , Humanos , Benzotiazoles/química , Benzotiazoles/metabolismo , Técnicas Biosensibles/métodos , Dicroismo Circular , ADN/química , ADN/metabolismo , Colorantes Fluorescentes/química , Espectrometría de Fluorescencia , Uracil-ADN Glicosidasa/metabolismo , Uracil-ADN Glicosidasa/química
4.
J Biomed Inform ; 156: 104674, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38871012

RESUMEN

OBJECTIVE: Biomedical Named Entity Recognition (bio NER) is the task of recognizing named entities in biomedical texts. This paper introduces a new model that addresses bio NER by considering additional external contexts. Different from prior methods that mainly use original input sequences for sequence labeling, the model takes into account additional contexts to enhance the representation of entities in the original sequences, since additional contexts can provide enhanced information for the concept explanation of biomedical entities. METHODS: To exploit an additional context, given an original input sequence, the model first retrieves the relevant sentences from PubMed and then ranks the retrieved sentences to form the contexts. It next combines the context with the original input sequence to form a new enhanced sequence. The original and new enhanced sequences are fed into PubMedBERT for learning feature representation. To obtain more fine-grained features, the model stacks a BiLSTM layer on top of PubMedBERT. The final named entity label prediction is done by using a CRF layer. The model is jointly trained in an end-to-end manner to take advantage of the additional context for NER of the original sequence. RESULTS: Experimental results on six biomedical datasets show that the proposed model achieves promising performance compared to strong baselines and confirms the contribution of additional contexts for bio NER. CONCLUSION: The promising results confirm three important points. First, the additional context from PubMed helps to improve the quality of the recognition of biomedical entities. Second, PubMed is more appropriate than the Google search engine for providing relevant information of bio NER. Finally, more relevant sentences from the context are more beneficial than irrelevant ones to provide enhanced information for the original input sequences. The model is flexible to integrate any additional context types for the NER task.


Asunto(s)
Procesamiento de Lenguaje Natural , PubMed , Humanos , Algoritmos , Minería de Datos/métodos , Semántica , Informática Médica/métodos
5.
Int J Mol Sci ; 25(6)2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38542356

RESUMEN

Nucleic acid modifications play important roles in biological activities and disease occurrences, and have been considered as cancer biomarkers. Due to the relatively low amount of nucleic acid modifications in biological samples, it is necessary to develop sensitive and reliable qualitative and quantitative methods to reveal the content of any modifications. In this review, the key processes affecting the qualitative and quantitative analyses are discussed, such as sample digestion, nucleoside extraction, chemical labeling, chromatographic separation, mass spectrometry detection, and data processing. The improvement of the detection sensitivity and specificity of analytical methods based on mass spectrometry makes it possible to study low-abundance modifications and their biological functions. Some typical nucleic acid modifications and their potential as biomarkers are displayed, and efforts to improve diagnostic accuracy are discussed. Future perspectives are raised for this research field.


Asunto(s)
Ácidos Nucleicos , Espectrometría de Masas/métodos , Biomarcadores de Tumor
6.
J Environ Manage ; 352: 120015, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38194873

RESUMEN

The most common construction material used in Taiwan is concrete, potentially contaminated by geologic heavy metals (HMs). Younger children spend much time indoors, increasing HM exposure risks from household dust owing to their behaviors. We evaluated arsenic (As), cadmium (Cd), and lead (Pb) concentrations in fingernails among 280 preschoolers between 2017 and 2023. We also analyzed HM concentrations, including As, Cd, Pb, chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), iron (Fe), and manganese (Mn), in 90 household dust and 50 road dust samples from a residential area where children lived between 2019 and 2021 to deepen the understanding of sources and health risks of exposure to HMs from household dust. The average As, Cd, and Pb concentrations in fingernails were 0.12 ± 0.06, 0.05 ± 0.05, and 0.95 ± 0.77 µg/g, respectively. Soil parent materials, indoor construction activities, vehicle emissions, and mixed indoor combustion were the pollution sources of HMs in household dust. Higher Cr and Pb levels in household dust may pose non-carcinogenic risks to preschoolers. Addressing indoor construction and soil parent materials sources is vital for children's health. The finding of the present survey can be used for indoor environmental management to reduce the risks of HM exposure and avoid potential adverse health effects for younger children.


Asunto(s)
Arsénico , Metales Pesados , Humanos , Preescolar , Cadmio , Monitoreo del Ambiente , Polvo/análisis , Plomo , Metales Pesados/análisis , Cromo , Medición de Riesgo , Suelo , China , Ciudades
7.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3644-3656, 2024 Jul.
Artículo en Zh | MEDLINE | ID: mdl-39041137

RESUMEN

To explore the mechanism of the classic formula Sanpian Decoction in treating chronic migraine, this study employed the four-dimensional data-dependent acquisition(4D-DIA) proteomics to analyze the effect of the decoction on chronic migraine in rats and experimentally verified the key differentially expressed proteins. Firstly, SD male rats were randomly divided into groups and repeatedly injected with nitroglycerin to prepare a chronic migraine model. After 7 consecutive days of gavage, rat grimace scale(RGS) was employed to evaluate the treatment efficacy. The trigeminal ganglion was collected for 4D-DIA proteomics, on the basis of which the diffe-rentially expressed proteins between groups were screened. Multiple databases were used for the Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment of the differentially expressed proteins. STRING and Cytoscape were employed to establish the protein-protein interaction(PPI) network. Western blot was employed to determine the expression level of the key diffe-rentially expressed protein TRPV1. The results showed that there were 517 differentially expressed proteins between blank group and model group and 221 differentially expressed proteins between model group and medium-dose Sanpian Decoction group. The GO and KEGG enrichment results showed that these differentially expressed proteins were mainly related to inflammatory response, injurious sensory stimulation, triglyceride metabolism, immune regulation, etc., which mainly involved the inflammation-related TRP, AMPK, PI3K-Akt, and TGF-ß signaling pathways. The PPI network showed that the target proteins such as IGF, TOP2A, APOA1, CDK1, TTN, RYR1, and CSRP3 had high degrees. Compared with that in model group, the expression level of TRPV1 altered in medium-and high-dose Sanpian Decoction group(P<0.05). In conclusion, Sanpian Decoction may treat chronic migraine by regulating the inflammation-related pathways such as TRP, AMPK, and PI3K-Akt. It plays an important role in the regulation of TRPV1 protein and potentially modulates the perception of injurious stimuli, lipid metabolism, and immune responses.


Asunto(s)
Medicamentos Herbarios Chinos , Trastornos Migrañosos , Proteómica , Ratas Sprague-Dawley , Animales , Trastornos Migrañosos/tratamiento farmacológico , Trastornos Migrañosos/metabolismo , Trastornos Migrañosos/genética , Ratas , Masculino , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/farmacología , Mapas de Interacción de Proteínas , Transducción de Señal/efectos de los fármacos , Enfermedad Crónica , Humanos
8.
Anal Chem ; 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36625376

RESUMEN

Succination is a nonenzymatic and irreversible post-translational modification (PTM) with important biological significance, yielding S-(2-succino) cysteine (2SC) residue. This PTM is low in abundance and often requires a large amount of protein samples for 2SC quantification. In this work, an efficient quantification method based on ethanol/acetyl chloride chemical derivatization was developed. The three carboxyl groups of 2SC were all esterified to increase hydrophobicity, greatly improving its ionization efficiency. The sensitivity was increased by 112 times; the limit of detection was reduced to 0.885 fmol, and the protein usage was reduced by at least 10 times. The established method was used to detect the overall concentration of 2SC in fumarate accumulation cells quantitatively.

9.
Virol J ; 20(1): 258, 2023 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-37950261

RESUMEN

BACKGROUND: Rabies is a widespread, fatal, infectious disease. Several antivirals against rabies virus (RABV) infection have been reported, but no approved, RABV-specific antiviral drugs that inhibit RABV infection in the clinic after symptom onset are available. Therefore, more effective drugs to reduce rabies fatalities are urgently needed. Bardoxolone methyl (CDDO-Me), an FDA-approved compound that has long been known as an antioxidant inflammatory modulator and one of the most potent nuclear factor erythroid-derived 2-like 2 (Nrf2) activators, protects myelin, axons, and CNS neurons by Nrf2 activation. Therefore, we investigated the potency of its anti-RABV activity in vitro. METHODS: The mouse neuroblastoma cell line Neuro2a (N2a) and three RABV strains of different virulence were used; the cytotoxicity and anti-RABV activity of CDDO-Me in N2a cells were evaluated by CCK-8 assay and direct fluorescent antibody (DFA) assay. Pathway activation in N2a cells infected with the RABV strains SC16, CVS-11 or CTN upon CDDO-Me treatment was evaluated by western blotting (WB) and DFA assay. RESULTS: CDDO-Me significantly inhibited infection of the three RABV strains of differing virulence (SC16, CVS-11 and CTN) in N2a cells. We also examined whether CDDO-Me activates the Nrf2-associated pathway upon infection with RABV strains of differing virulence. Nrf2, phosphorylated sequestosome (SQSTM1), SQSTM1, hemoglobin oxygenase (HO-1) and NAD(P)H dehydrogenase quinone 1 (NQO1) expression in N2a cells increased to varying degrees with CDDO-Me treatment, accompanied by Kelch-like ECH-associated protein 1 (Keap1) dissociation, upon infection with SC16, CVS-11 or CTN. The activation of SQSTM1 phosphorylation was significantly associated with the degradation of Keap-1 in CDDO-Me-treated N2a cells upon RABV infection. Furthermore, N2a cells pretreated with the Nrf2-specific inhibitor ATRA showed a significant decrease in HO-1 and NQO1 expression and a decrease in the anti-RABV efficacy of CDDO-Me. These inhibitory effects were observed upon infection with three RABV strains of differing virulence. CONCLUSION: CDDO-Me inhibited RABV infection via Nrf2 activation, promoting a cytoprotective defense response in N2a cells. Our study provides a therapeutic strategy for RABV inhibition and neuroprotection during viral infection.


Asunto(s)
Virus de la Rabia , Rabia , Ratones , Animales , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Rabia/tratamiento farmacológico , Proteína Sequestosoma-1/metabolismo
10.
Analyst ; 148(7): 1500-1506, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36883656

RESUMEN

Nucleosides have been found to suffer in-source fragmentation (ISF) in electrospray ionization mass spectrometry, which leads to reduced sensitivity and ambiguous identification. In this work, a combination of theoretical calculations and nuclear magnetic resonance analysis revealed the key role of protonation at N3 near the glycosidic bond during ISF. Therefore, an ultrasensitive liquid chromatography-tandem mass spectrometry system for 5-formylcytosine detection was developed with 300 fold signal enhancement. Also, we established a MS1-only platform for nucleoside profiling and successfully identified sixteen nucleosides in the total RNA of MCF-7 cells. Taking ISF into account, we can realize analysis with higher sensitivity and less ambiguity, not only for nucleosides, but for other molecules with similar protonation and fragmentation behaviors.


Asunto(s)
Nucleósidos , Espectrometría de Masa por Ionización de Electrospray , Nucleósidos/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida
11.
Environ Geochem Health ; 45(8): 6267-6286, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37289259

RESUMEN

Health risk assessments of exposure to mercury (Hg) from soils via ingestion and inhalation are indispensable for Taiwanese people living in the vicinity of Hg-contaminated sites. In this study, anthropogenic soils were collected from various polluted sources in Taiwan. In vitro oral and inhalation bioaccessible fractions of Hg were analyzed to avoid from overestimating the exposure risk. Discrepancies in oral and inhalation bioaccessible levels of Hg in soils were found using different in vitro assays with different pH levels and chemical compositions. The freshly contaminated soil (soil S7) polluted by chlor-alkali production activity sampled before the site was remediated had the highest total Hg concentration of 1346 mg/kg, with the highest oral bioaccessibility of 26.2% as analyzed by SW-846 Method 1340 and inhalation bioaccessibility of 30.5% as analyzed by modified Gamble's solution. The lesser extent of aging of Hg in soil S7 increased the Hg availability for humans, which was also found based on results of a sequential extraction procedure. Results of the hazard quotient showed that soil ingestion was the main pathway causing non-carcinogenic risks for children and adults. Children were also exposed to higher risks than were adults due to higher frequencies of hand-to-mouth behaviors and lower body weights. Furthermore, hazard index results adjusted for oral and inhalation bioaccessible Hg were lower than those obtained based on the total Hg content; however, an unacceptable value of the non-carcinogenic risk (> 1) for children living near soil S7 was still observed. This study suggests that children living near sites polluted for a short period of time may suffer potential renal effects regardless of the bioaccessibility. Our findings provide suggestions for decision makers on setting new strategies for managing risks of Hg-contaminated soils in Taiwan.


Asunto(s)
Mercurio , Contaminantes del Suelo , Adulto , Niño , Humanos , Mercurio/análisis , Taiwán , Contaminación Ambiental/análisis , Suelo/química , Medición de Riesgo , Riñón , Contaminantes del Suelo/análisis , Monitoreo del Ambiente
12.
Am J Physiol Cell Physiol ; 322(5): C814-C824, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35319902

RESUMEN

Cachexia is a complex metabolic syndrome that occurs in approximately 50% of patients with cancer. Skeletal muscle atrophy is the primary clinical feature. Interleukin (IL)-17A, a proinflammatory factor, plays an important role in many chronic inflammatory diseases. Here, we describe a novel signaling pathway through which IL-17A induced muscle atrophy. We conducted a retrospective clinical study to investigate the relationship between IL-17A and the skeletal muscle index in patients with lung adenocarcinoma. We also investigated the involvement of JAK2/STAT3 signaling pathway regarding the main features of cachexia by injecting Lewis lung carcinoma (LLC) cells into C57BL/6 mice as a model to replicate cancer-induced cachexia. In vitro, C2C12 myotubes were treated with recombinant IL-17A, anti-IL-17A monoclonal antibody, STAT3 inhibitor AG490, and LLC-conditioned medium. Cell viability and aging were also evaluated. We found that in cancer conditions, increased serum levels of IL-17A were related to muscle wasting. JAK2/STAT3 phosphorylation was observed in the muscle of LLC tumor-bearing mice, accompanied by decreased MHC/Myog levels and increased MuRF1/Atrogin-1 levels. Administration of anti-IL-17A monoclonal antibody and AG490 slowed muscle atrophy development. Consistent with the in vivo findings, C2C12 myotubes treated with IL-17A and LLC-conditioned medium demonstrated phosphorylated JAK2/STAT3 signaling, resulting in MHC loss and myotube atrophy. IL-17A also inhibited C2C12 cell proliferation, cell cycle breaking, and cellular senescence. Our results identify that phosphorylation of IL-17A/JAK2/STAT3 signaling pathway appears to be an important component in the pathogenesis of LLC tumor-induced cachexia. Targeted therapy of IL-17A may be a promising approach to reduce skeletal muscle loss in patients with cancer.


Asunto(s)
Carcinoma Pulmonar de Lewis , Neoplasias Pulmonares , Animales , Anticuerpos Monoclonales/metabolismo , Anticuerpos Monoclonales/uso terapéutico , Caquexia/metabolismo , Carcinoma Pulmonar de Lewis/metabolismo , Medios de Cultivo Condicionados/metabolismo , Medios de Cultivo Condicionados/farmacología , Humanos , Interleucina-17/metabolismo , Janus Quinasa 2/metabolismo , Neoplasias Pulmonares/metabolismo , Ratones , Ratones Endogámicos C57BL , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Atrofia Muscular/patología , Estudios Retrospectivos , Factor de Transcripción STAT3/metabolismo
13.
Anal Chem ; 94(22): 8066-8074, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35613360

RESUMEN

Oxidative DNA damage is tightly linked to the development of multiple age-related diseases. The prominent oxidation product is 8-oxo-7,8-dihydroguanine (OG), which has been proved to be an important epigenetic-like biomarker. Quantification of the locus-specific OG frequency includes quantitative and locating information, which is of great significance for exploring the functional roles of OG in disease induction and gene regulation. Herein, an ultrasensitive quantification of OG at single-base resolution was established using real-time fluorescence quantitative polymerase chain reaction as an amplification tool. Based on the coding property of Bsu DNA polymerase that incorporates adenine on the opposite site of OG and the selectivity of the ligase for perfectly matched sequences, the difference between OG and G on the sequence could be enlarged. Well-performed Taq DNA ligase was selected out, and as low as 46.2 zmol of target DNA with an OG site and an OG frequency of 5% could be detected. G contents on a specific site were also detectable based on the similar principle, thus the OG frequency of this locus could be accurately determined by a standard addition method. This strategy was successfully applied to the evaluation of locus-specific OG in both model DNA and genomic DNA from human cervical carcinoma cell lines under multiple oxidative stress, showing the potential for functional research and dynamic monitoring of critical OG sites.


Asunto(s)
Reparación del ADN , Guanina , ADN/genética , Daño del ADN , Guanina/análogos & derivados , Humanos
14.
Anal Chem ; 94(21): 7584-7593, 2022 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-35588463

RESUMEN

In this study, we examined the influence of functionalized poly(3,4-ethylenedioxythiophene) (PEDOT) nanostructures decorated on the channel layer of an organic electrochemical transistor (OECT) for the detection of sweat cortisol, an adrenocorticosteroid stress hormone. The OECT device featured a bilayer channel confined by a PEDOT:polystyrenesulfonate (PSS) underlayer and a nanostructure-decorated upper layer engineered from the monomers EDOT-COOH and EDOT-EG3 through template-free electrochemical polymerization. This molecular design allowed antibody conjugation using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide/N-hydroxysulfosuccinimide coupling through the carboxylic acid side chain, with EDOT-EG3 known to minimize nonspecific binding of biomolecules. We also engineered an OECT device having a channel area without any nanostructures to gain insight into the effect of the nanostructures on cortisol sensing. Our new nanostructure-embedded OECT device facilitated real-time detection of cortisol at concentrations ranging from 1 fg/mL to 1 µg/mL with a detection limit of 0.0088 fg/mL with good linearity (R2 = 0.9566), in addition to excellent selectivity toward cortisol among other structurally similar interfering compounds and high stability and reproducibility. With its rapid response for the detection of 100 ng/mL cortisol-spiked artificial sweat, this nanostructure-decorated OECT device has potential clinical practicality and utility in wearable sensors for future healthcare applications.


Asunto(s)
Nanoestructuras , Sudor , Compuestos Bicíclicos Heterocíclicos con Puentes , Hidrocortisona , Poli A , Polímeros , Reproducibilidad de los Resultados
15.
Environ Res ; 212(Pt B): 113344, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35461849

RESUMEN

Mercury (Hg) is a well-known toxicant that can affect children's neurodevelopment. This study attempted to evaluate the internal dose of Hg in hair and fingernails and external Hg exposure from dietary consumption in 283 pairs of mothers and their children aged under 6 years in Taiwan. Mean Hg levels in hair and fingernail samples were 1.07 ± 0.67 and 0.42 ± 0.34 µg/g for mothers, and 1.11 ± 1.22 and 0.36 ± 0.26 µg/g for children, respectively. Our results showed that 42% of mothers and 41% of children had hair Hg levels exceeding the US Environmental Protection Agency recommended value of 1 µg/g. Hg exposure in children was greater than that of their mothers. Estimated daily intake (EDI) levels of Hg among preschool children were 3.3-times higher than those of their mothers. A sensitivity analysis indicated that fish consumption was the main potential factor of Hg exposure among both mothers and their children. External Hg exposure using estimated daily dietary ingestion by mothers was a surrogate for internal hair Hg concentrations. However, poor correlations were found between EDI Hg levels and hair Hg levels among children aged 4-6 years. Exposure sources from food and other media, such as soil and dust, need to be considered to arrive at more-valid risk assessments for younger children's exposure to Hg. Children of mothers who did not have food safety-related risk perceptions or protective behaviors had significantly higher hair Hg concentrations compared to children whose mothers had risk perceptions and protective behaviors. Hg exposure of women of childbearing age and preschool children in Taiwan is still an area of great concern. Providing food safety information and risk-benefits of fish consumption for mothers may avoid harm to the developing nervous systems of their children.


Asunto(s)
Mercurio , Animales , Preescolar , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente , Femenino , Peces , Contaminación de Alimentos/análisis , Inocuidad de los Alimentos , Cabello/química , Humanos , Mercurio/análisis
16.
Int J Mol Sci ; 23(9)2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35563341

RESUMEN

In nature, many different factors cause plants to develop variegated leaves. To explore the mechanism of variegated leaf formation in Pteroceltis tatarinowii, a mutant variety ('Jinyuyuan'), which was induced by ethylmethylsulfone, was selected, and its morphological structure, physiology, biochemistry, transcription and metabolism were analysed. According to differences in colour values, the colours were divided into two regions: a green region and a yellow-green region. The chlorophyll content of the two regions was significantly different. Moreover, the yellow-green regions of the leaves were significantly thinner than the green regions. The chloroplast ultrastructure in the yellow-green region revealed small chloroplasts, large vacuoles, small starch grains, obviously increased numbers of osmophilic grains, loose lamellae of the inner capsule and thin lamellae. Moreover, the yellow-green region was accompanied by oxidative stress, and the activity of the oxidative phosphorylation pathway related to oxidative activity in the transcriptome showed an upward trend. Vitamin B6 and proline contents also increased, indicating that the antioxidant activity of cells in the yellow-green region increased. Transcriptomic and metabolomic analysis showed that the differentially expressed genes (DEGs) related to chlorophyll synthesis and metabolism led to a decrease in the photosynthesis and then a decrease in the assimilation ability and contents of sucrose, starch and other assimilates. Amino acid synthesis and metabolism, lipid synthesis and the activity of metabolic pathways were obviously downregulated, and the contents of differentially accumulated metabolites associated with amino acids and lipids were also reduced. At the same time, 31 out of 32 DEGs involved in the flavonoid synthesis pathway were downregulated, which affected leaf colour. We hypothesized that the variegated leaves of P. tatarinowii 'Jinyuyuan' are caused by transcriptional and post-transcriptional regulation. Mutations in pigment and flavonoid synthesis pathway genes and transcription factor genes directly affect both pigment and flavonoid synthesis and degradation rate, which in turn affect carbon assimilation, carbon fixation, related protein synthesis and enzyme activity, lipid synthesis and degradation and the activity of other metabolic pathways, eventually leading to the formation of different colour regions.


Asunto(s)
Transcriptoma , Árboles , Clorofila/metabolismo , Flavonoides/metabolismo , Regulación de la Expresión Génica de las Plantas , Metaboloma , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Almidón/metabolismo , Árboles/genética
17.
Molecules ; 27(20)2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36296634

RESUMEN

Early cancer diagnosis is essential for successful treatment and prognosis, and modified nucleosides have attracted widespread attention as a promising group of cancer biomarkers. However, analyzing these modified nucleosides with an extremely low abundance is a great challenge, especially analyzing multiple modified nucleosides with a different abundance simultaneously. In this work, an ultrasensitive quantification method based on chemical labeling, coupled with LC-MS/MS analysis, was established for the simultaneous quantification of 5hmdC, 5fdC, 5hmdU and 5fdU. Additionally, the contents of 5mdC and canonical nucleosides could be obtained at the same time. Upon derivatization, the detection sensitivities of 5hmdC, 5fdC, 5hmdU and 5fdU were dramatically enhanced by several hundred times. The established method was further applied to the simultaneous detection of nine nucleosides with different abundances in about 2 µg genomic DNA of breast tissues from 20 breast cancer patients. The DNA consumption was less than other overall reported quantification methods, thereby providing an opportunity to monitor rare, modified nucleosides in precious samples and biology processes that could not be investigated before. The contents of 5hmdC, 5hmdU and 5fdU in tumor tissues and normal tissues adjacent to the tumor were significantly changed, indicating that these three modified nucleosides may play certain roles in the formation and development of tumors and be potential cancer biomarkers. While the detection rates of 5hmdC, 5hmdU and 5fdU alone as a biomarker for breast cancer samples were 95%, 75% and 85%, respectively, by detecting these three cancer biomarkers simultaneously, two of the three were 100% consistent with the overall trend. Therefore, simultaneous detection of multiple cancer biomarkers in clinical samples greatly improved the accuracy of cancer diagnosis, indicating that our method has great application potential in clinical multidimensional diagnosis.


Asunto(s)
Neoplasias de la Mama , Nucleósidos , Humanos , Femenino , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , ADN/química , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/análisis
18.
Eat Weight Disord ; 27(8): 3389-3398, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36071328

RESUMEN

PURPOSE: The main objective of the study was to translate, validate, and compare the Chinese ORTO scales (ORTO-15 and ORTO-R). The secondary objective was to assess factors that may be related with risk of orthorexia nervosa (ON). METHODS: Two cross-sectional surveys were conducted on March-to-June 2021 for ORTO-15 and April 2022 for ORTO-R. ORTO questionnaires were translated into Chinese using the forward-backward-forward method. Exploratory factor analysis (EFA), discriminant validity and confirmatory factor analysis (CFA) were used to examine the construct validity of the questionnaires. The internal consistency was assessed using the Cronbach alpha coefficient and the test-retest reliability. Multivariate linear regression analysis was used to explore potential factors related with ON scores. RESULTS: Totally, 1289 and 1084 eligible participants were included for assessment of ORTO-15 and ORTO-R, with the mean age of 20.9 ± 2.0 years and 21.0 ± 2.3 years. The internal consistency of Chinese ORTO-15 scale and ORTO-R scale were both satisfactory (α = 0.79, ICC = 0.79; α = 0.77, ICC = 0.82). However, all ORTO-15 models showed a poor fit using CFA whereas the ORTO-R was characterized by acceptable goodness-of-fit. Multivariate linear regression indicated that physical activities and mental disorders were positively associated with ON risk assessed by both ORTO-R and ORTO-15. CONCLUSION: The Chinese ORTO-R scale was a more reliable tool to screen for ON tendencies than the Chinese version of ORTO-15. Mental disorders and physical activities might be associated with the increased ON risk. LEVEL OF EVIDENCE: Level V (descriptive cross-sectional study).


Asunto(s)
Trastornos de Alimentación y de la Ingestión de Alimentos , Conductas Relacionadas con la Salud , Humanos , Adolescente , Adulto Joven , Adulto , Ortorexia Nerviosa , Estudios Transversales , Reproducibilidad de los Resultados , Trastornos de Alimentación y de la Ingestión de Alimentos/diagnóstico , Estudiantes , Encuestas y Cuestionarios , Psicometría/métodos
19.
Anal Chem ; 93(45): 14907-14911, 2021 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-34735132

RESUMEN

Exosomes are nanosized extracellular vesicles that have a critical role in intercellular communication and tumor microenvironment regulation. Extensive research has shown that exosomal small RNAs contribute to metastasis in multiple tumor types and that abnormal epigenetic modifications in nucleic acids also have an association with diverse diseases. However, the content of modified nucleosides on exosomal small RNAs has not been quantitatively reported. Because of the trace amounts of exosomes and matrix complexity, we used liquid chromatography-tandem mass spectrometry (LC-MS/MS) as a powerful tool for label-free sensitive and simultaneous determinations of six important modified nucleosides on small RNAs inside exosomes. This system performed well using only approximately 107-108 particles of exosomes to obtain modified nucleoside levels between 0.001 and 0.03, and the most striking result was that the content of m6A in exosomal small RNAs was continuously higher than that in the cells being analyzed. We hope that this conclusion helps establish a greater degree of deciphering accuracy on exosomes, which has considerable application potential in the diagnosis and prognosis of diseases.


Asunto(s)
Exosomas , ARN , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Epigénesis Genética , Exosomas/genética , Espectrometría de Masas en Tándem
20.
Environ Sci Technol ; 55(17): 11805-11813, 2021 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-34388337

RESUMEN

This study focuses on estimating the probabilistic soil and dust ingestion rates for children under 3 years old by the Stochastic Human Exposure and Dose Simulation Soil and Dust (SHEDS-S/D) model developed by the U.S. Environmental Protection Agency. The health risk of children's exposure to heavy metals through soil and dust ingestion and dermal absorption was then assessed in three exposure scenarios. In the exposure scenario of direct contact with soil, the average soil and dust ingestion rates for children aged 24 to 36 months were 90.7 and 29.8 mg day-1 in the sand and clay groups, respectively. Hand-to-mouth soil ingestion was identified as the main contributor to soil and dust ingestion rates, followed by hand-to-mouth dust ingestion and object-to-mouth dust ingestion. The soil-to-skin adherence factor was the most influential factor increasing the soil and dust ingestion rate based on a sensitivity analysis in the SHEDS-S/D model. Furthermore, the modeled soil and dust ingestion rates based on the SHEDS-S/D model were coincident with results calculated by the tracer element method. Our estimates highlight the soil ingestion rate as the key parameter increasing the risk for children, while a higher frequency of hand washing could potentially reduce the risk.


Asunto(s)
Polvo , Suelo , Niño , Preescolar , Polvo/análisis , Ingestión de Alimentos , Exposición a Riesgos Ambientales/análisis , Humanos , Medición de Riesgo , Taiwán
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