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1.
Plant Dis ; 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38050401

RESUMO

Coreopsis tinctoria is an annual herb and commonly cultivated in gardens due to its attractive flowers, its capitula also have been used as a traditional medicine in China, Asia, North America and Europe (Shen et al. 2021). In June 2023, severe powdery mildew infection was observed on C. tinctoria in a hillside near headwork of the middle route of the South to North Water Diversion Project (32°40'55''N, 111°41'59''E). Abundant irregular white spots were found on adaxial surface of the leaves and tender stems. Approximately 75% of the observed C. tinctoria plants showed these signs and symptoms. Generative hyphae were thin-walled, smooth or almost so, and 5 to 9 µm wide. Conidiophores were unbranched, straight, 80.5 to 162.5 × 9.3 to 12.9 µm (n=25), and produced one to three immature conidia. Foot-cells of conidiophores were cylindrical, 38.5 to 62.3 µm (n=20) long. Conidia were ellipsoid to ovoid, 25.1 to 31.9 × 15.2 to 19.5 µm (n=30). The morphological characteristics of asexual structures corresponded to Podosphaera sp. (Braun and Cook 2012). For further identification, genomic DNA was extracted directly from the mycelia and conidia using Chelex 100 (Sigma Aldrich, Shanghai, China). The internal transcribed spacer (ITS) regions and 28S large subunit (LSU) of ribosomal DNA from the specimen (CT2302) were amplified using the primers ITS1/ITS4 (expected amplicon size 566 bp) (White et al. 1990) and NL1/NL4 (expected amplicon size 618 bp) (Baten et al. 2014), respectively. The sequences of ITS (GenBank accession no. OR649304) and LSU (GenBank accession no. OR649305) showed 99.63% and 100% identity values to the Podosphaera fusca isolate HMNWAFU-CF2012074 in the NCBI database (KR048109 for ITS and KR048178 for LSU), respectively. Phylogenetic analyses based on the combined ITS and LSU sequences using MEGA 7.0 software indicated that CT2302 formed a monophyletic clade together with isolates of P. fusca. Therefore, this fungus was identified as P. fusca based on the morphological and molecular characteristics. Pathogenicity tests were performed by gently pressing the infected leaves onto 15 young leaves of five healthy plants and three noninoculated plants were used as controls. All plants were maintained in a greenhouse (25℃ and 70% relative humidity). Powdery mildew symptoms similar to those of originally diseased plants were observed on all inoculated leaves after 12 days, whereas no symptoms were observed on the control leaves. Powdery mildew caused by P. fusca (previously Sphaerotheca fusca) on C. tinctoria has been reported in Russia, Poland, Korea, Romania and Ukraine (Cho and Shin 2004; Rusanov and Bulgakow 2008). To our knowledge, this is the first report of P. fusca on C. tinctoria in China. The identification of P. fusca as the causal agent on C. tinctoria is critical to the prevention and control of this disease in the future.

2.
Angew Chem Int Ed Engl ; 61(9): e202113051, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-34881475

RESUMO

Accurate quantification of disease-signature microRNAs (miRNAs) in biomedical samples is in high demand for clinical diagnosis but still challenging because of the low abundance of miRNAs and complicating interferences in the milieus. Here, we report a multi-amplification strategy based on paper-spray mass spectrometry (PS MS) for the analysis of miRNAs in blood. A toehold-mediated DNA-strand-displacement reaction (TSD) is employed to amplify the signal chain and to ensure the specificity. The signal chain is then cleaved by UV light to release signal molecules for detection. Moreover, the paper spray method can efficiently filter out interfering substances in the blood and further enhance the sensitivity of detection. This concept is successfully demonstrated in the prototypical detection of the cancer biomarker miRNA-141 in blood and serum. The proposed TSD-PS MS approach provides an efficient method for the sensitive detection of oligonucleotides at low concentration in complicated milieus.


Assuntos
Biomarcadores Tumorais/sangue , DNA/química , MicroRNAs/sangue , Neoplasias/sangue , Técnicas de Amplificação de Ácido Nucleico , Papel , Técnicas Biossensoriais , Humanos , Espectrometria de Massas , Neoplasias/patologia
3.
Anal Chem ; 93(3): 1749-1756, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33351590

RESUMO

Significant efforts have been made to develop robust and reliable methods for simultaneous biothiols determination in different matrices, but there still exist the problems such as easy oxidation, tedious derivatization, and difficulty in discrimination, which brings unsatisfactory results in their accuracy and fast quantification in biological samples. To overcome these problems, a simultaneous biothiols detection method combining a "selenium signature" chemical probe and paper spray mass spectrometry (PS-MS) was proposed. In the strategy, the modified-paper substrate is used to enhance the analytical performance. Chemical probe Ebselen-NH2 that has a specific response to biothiols was designed and covalently fixed on the surface of an oxidized paper substrate. By the identification of derivatized product with distinctive selenium isotope distribution and employment of the optimized PS-MS method, qualitative and quantitative analysis of five biothiols including glutathione (GSH), cysteine (Cys), cysteinylglycine (CysGly), N-acetylcysteine (Nac), and homocysteine (Hcy) were realized. Biothiols in plasma and cell lysates were measured with satisfactory results. The established method not only provides a novel protocol for simultaneous determination of biothiols, but also is helpful for understanding the biological and clinical roles played by these bioactive small molecules.


Assuntos
Acetilcisteína/análise , Cisteína/análise , Dipeptídeos/análise , Corantes Fluorescentes/química , Glutationa/análise , Papel , Selênio/química , Técnicas Biossensoriais , Cisteína/análogos & derivados , Humanos , Espectrometria de Massas
4.
Phys Chem Chem Phys ; 22(37): 21393-21402, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32940309

RESUMO

Long-range electron transfer in proteins can be rationalized as a sequential short-distance electron-hopping processes via amino acid residues having low ionization energy as relay stations. Tyrosine residues can serve as such redox-active intermediates through one-electron oxidation to form a π-radical cation at its phenol side chain. An electron transfer from a vicinal functional group to this π-electron hole completes an elementary step of charge migration. However, transient oxidized/reduced intermediates formed at those relay stations during electron transfer processes have not been observed. In this study, formation of analog reactive intermediates via electron donor-acceptor coupling is observed by using IRMPD action spectroscopy. An elementary charge migration at the molecular level in model tyrosine-containing peptide radical cations [M]˙+ in the gas phase is revealed with its unusual Cα-Cß bond cleavage at the side chain of the N-terminal residue. This reaction is induced by the radical character of the N-terminal amino group (-NH2˙+) resulting from an n → π+ interaction between the nonbonding electron pair of NH2 (n) and the π-electron hole at the Tyr side chain (π+). The formation of -NH2˙+ is supported by the IRMPD spectrum showing a characteristic NH2 scissor vibration coupled with Tyr side-chain stretches at 1577 cm-1. This n → π+ interaction facilitates a dissociative electron transfer with NH2 as the relay station. The occurrence of this side-chain cleavage may be an indicator of the formation of reactive conformers featuring the n → π+ interaction.


Assuntos
Elétrons , Radicais Livres/química , Peptídeos/química , Tirosina/química , Oxirredução , Conformação Proteica
5.
Med Sci Monit ; 26: e922092, 2020 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-32277808

RESUMO

BACKGROUND Despite scientific advancement in radiotherapy and chemotherapy, the 5-year survival rate of lung cancer patients is around 15%. The present study explored the anticancer potential of betulinic acid nanoparticles against lung cancer cells. MATERIAL AND METHODS The proliferative changes in lung cancer cells by betulinic acid nanoparticles were measured by MTT assay. Cell cycle analysis was performed by flow cytometry using propidium iodide stain. Transwell and wound healing assay were used for determination of HKULC2 cell metastatic potential. RESULTS The betulinic acid nanoparticle treatment significantly (P<0.05) reduced proliferation of HKULC2, H1299, and H23 cells. The proliferation of HKULC2, H1299, and H23 cells was reduced to 33%, 28% and 24%, respectively on treatment with 10 µM of betulinic acid nanoparticles. The results from flow cytometry showed that betulinic acid nanoparticle exposure lead to cell cycle arrest in G1 phase in HKULC2 cells. Treatment with betulinic acid nanoparticles markedly decreased migration potential of HKULC2 cells. The invasive ability of HKULC2 cells was also suppressed markedly on exposure to betulinic acid nanoparticles. Western blotting of HKULC2 cells showed that betulinic acid nanoparticles promoted the expression of p21 and p53 and downregulated CD133, ALDH, BCL2, MCL1, and c-Myc expression. Betulinic acid nanoparticles reduced the expression of ABCG1 protein markedly. CONCLUSIONS The present study demonstrated that betulinic acid nanoparticles inhibit proliferation, metastatic ability, and arrest cell cycle in lung cancer cells through downregulation of ABCG1 oncogene expression. Therefore, betulinic acid nanoparticles may be used as therapeutic agent for the treatment of lung cancer.


Assuntos
Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Antineoplásicos Fitogênicos/farmacologia , Neoplasias Pulmonares/patologia , Triterpenos/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas , Triterpenos Pentacíclicos , Ácido Betulínico
6.
Chin Med Sci J ; 34(4): 292-296, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33906716

RESUMO

A 61-year-old Chinese woman was diagnosed as primary pulmonary adenocarcinoma of left superior lobe with epidermal growth factor receptor (EGFR) 19 del mutation positive. Treatment with icotinib was given, but her disease progressed after 6 months remission. CT-guide needle biopsy for the new lesion in inferior lobe of left lung demonstrated intrapulmonary metastasis, and EGFR gene panel by Amplification Refractory Mutation System Polymerase Chain Reaction (ARMS-PCR) confirmed EGFR T790M mutation. Treatment with osimertinib was initiated. After 2 months remission, the disease progressed. Re-biopsy was performed for the tumor in the inferior lobe of left lung, and ARMS-PCR demonstrated no other gene mutation except EGFR 19 del. Icotinib was re-challenged, but disease progressed continuously. Bevacizumab was added, and partial response was achieved after 2-cycle of combination therapy. The non-small cell lung cancer (NSCLC) in this case maintained EGFR activating mutation and lost EGFR T790M mutation was a genetic change after osimertinib treatment. This case suggests the re-challenge of the first-generation EGFR-TKIs combined with bevacizumab may overcome the tumor resistance and prolong survival of NSCLC patient.


Assuntos
Acrilamidas/uso terapêutico , Compostos de Anilina/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Éteres de Coroa/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/tratamento farmacológico , Quinazolinas/uso terapêutico , Acrilamidas/farmacologia , Adenocarcinoma de Pulmão/diagnóstico por imagem , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/patologia , Compostos de Anilina/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Bevacizumab/farmacologia , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Éteres de Coroa/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Pessoa de Meia-Idade , Quinazolinas/farmacologia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
7.
Chem Rec ; 18(1): 20-44, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28650100

RESUMO

Radical-mediated dissociations of peptide radical cations have intriguing unimolecular gas phase chemistry, with cleavages of almost every bond of the peptide backbone and amino acid side chains in a competitive and apparently "stochastic" manner. Challenges of unraveling mechanistic details are related to complex tautomerizations prior to dissociations. Recent conjunctions of experimental and theoretical investigations have revealed the existence of non-interconvertible isobaric tautomers with a variety of radical-site-specific initial structures, generated from dissociative electron transfer of ternary metal-ligand-peptide complexes. Their reactivity is influenced by the tautomerization barriers, perturbing the nature, location, or number of radical and charge site(s), which also determine the energetics and dynamics of the subsequent radical-mediated dissociatons. The competitive radical- and charge-induced dissociations are extremely dependent on charge density. Charge sequesting can reduce the charge densities on the peptide backbone and hence enhance the flexibility of structural rearrangement. Analysing the structures of precursors, intermediates and products has led to the discovery of many novel radical migration prior to peptide backbone and/or side chain fragmentations. Upon these successes, scientists will be able to build peptide cationic analogues/tautomers having a variety of well-defined radical sites.


Assuntos
Peptídeos/química , Cátions/química , Radicais Livres/química
8.
Phys Chem Chem Phys ; 19(25): 16923-16933, 2017 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-28631796

RESUMO

Four isomers of the radical cation of tripeptide phenylalanylglycyltryptophan, in which the initial location of the radical center is well defined, have been isolated and their collision-induced dissociation (CID) spectra examined. These ions, the π-centered [FGWπ˙]+, α-carbon- [FGα˙W]+, N-centered [FGWN˙]+ and ζ-carbon- [Fζ˙GW]+ radical cations, were generated via collision-induced dissociation (CID) of transition metal-ligand-peptide complexes, side chain fragmentation of a π-centered radical cation, homolytic cleavage of a labile nitrogen-nitrogen single bond, and laser induced dissociation of an iodinated peptide, respectively. The π-centered and tryptophan N-centered peptide radical cations produced almost identical CID spectra, despite the different locations of their initial radical sites, which indicated that interconversion between the π-centered and tryptophan N-centered radical cations is facile. By contrast, the α-carbon-glycyl radical [FGα˙W]+, and ζ-phenyl radical [Fζ˙GW]+, featured different dissociation product ions, suggesting that the interconversions among α-carbon, π-centered (or tryptophan N-centered) and ζ-carbon-radical cations have higher barriers than those to dissociation. Density functional theory calculations have been used to perform systematic mechanistic investigations on the interconversions between these isomers and to study selected fragmentation pathways for these isomeric peptide radical cations. The results showed that the energy barrier for interconversion between [FGWπ˙]+ and [FGWN˙]+ is only 31.1 kcal mol-1, much lower than the barriers to their dissociation (40.3 kcal mol-1). For the [FGWπ˙]+, [FGα˙W]+, and [Fζ˙GW]+, the barriers to interconversion are higher than those to dissociation, suggesting that interconversions among these isomers are not competitive with dissociations. The [z3 - H]˙+ ions isolated from [FGα˙W]+ and [Fζ˙GW]+ show distinctly different fragmentation patterns, indicating that the structures of these ions are different and this result is supported by the DFT calculations.

9.
Phys Chem Chem Phys ; 18(16): 11168-75, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27048940

RESUMO

Peptide radical cations that contain an aromatic amino acid residue cleave to give [zn - H]˙⁺ ions with [b2 - H - 17]˙⁺ and [c1 - 17](+) ions, the dominant products in the dissociation of [zn - H]˙⁺, also present in lower abundance in the CID spectra. Isotopic labeling in the aromatic ring of [Yπ˙GG](+) establishes that in the formation of [b2 - H - 17]˙⁺ ions a hydrogen from the δ-position of the Y residue is lost, indicating that nucleophilic substitution on the aromatic ring has occurred. A preliminary DFT investigation of nine plausible structures for the [c1 - 17](+) ion derived from [Y(π)˙GG](+) shows that two structures resulting from attack on the aromatic ring by oxygen and nitrogen atoms from the peptide backbone have significantly better energies than other isomers. A detailed study of [Y(π)˙GG](+) using two density functionals, B3LYP and M06-2X, with a 6-31++G(d,p) basis set gives a higher barrier for attack on the aromatic ring of the [zn - H]˙⁺ ion by nitrogen than by the carbonyl oxygen. However, subsequent rearrangements involving proton transfers are much higher in energy for the oxygen-substituted isomer leading to the conclusion that the [c1 - 17](+) ions are the products of nucleophilic attack by nitrogen, protonated 2,7-dihydroxyquinoline ions. The [b2 - H - 17]˙⁺ ions are formed by loss of glycine from the same intermediates involved in the formation of the [c1 - 17](+) ions.


Assuntos
Amidas/química , Nitrogênio/química , Íons , Espectrometria de Massas , Estrutura Molecular
10.
Langmuir ; 31(9): 2922-30, 2015 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-25705920

RESUMO

Self-assembled monolayers (SAMs) have been widely employed as etching resists in wet lithography systems to form patterns in which the ordered molecular packing of the SAM regions significantly delays the etchant attack. A generally accepted recognition is that the SAMs ability to resist etching is positively correlated to the quality of the surface-assembled structures, and a more ordered molecular packing would correspond to a better etching resistance. Such a classical belief is debated in the present work by providing an alternative SAM-assisted negative lithography where ordered SAM regions are etched more quickly than their disordered counterparts. This method features a unique photoirradiation-imprinted patterning process that simply consists of two steps: (1) UV irradiation on an OH-terminated SAM-modified gold surface through a photomask and (2) the subsequent immersion of the exposed substrate in an aqueous etching solution of N-bromosuccinimide/pyridine to develop a wet lithographic pattern. The entire experimental process reveals a finding from previous work that the etching rate on the UV-exposed regions with disordered molecular packing could be modulated to be slower than that in the unexposed well-defined SAM regions. Longer irradiation times would also revert the patterns from negative to positive. Thus, by merely using one kind of SAM-modified surface to provide both positive and negative micropatterns on gold layers, one could obtain flexible opportunities for high-resolution micro/nanofabrication resembling photolithography.

11.
Langmuir ; 30(17): 4945-51, 2014 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-24716839

RESUMO

The well-controlled material assembly and patterning on indium tin oxide (ITO) coating layer is of great importance for the practical fabrication of a functional device. Nonetheless, the conventional way to achieve this aim is still mainly based on the combination of photolithography with pattern transfer techniques (e.g., wet/dry etching, µCP) due to the lack of one method that is able to directly afford site-selective ITO surface tailoring and subsequent templating for material assembly. Herein, we reported a novel, fast, and efficient photochemical reaction to accurately tailor the surface property of ITO with light-controlled site-selectivity, thus resulting in direct photoresist-free and etching/contact-free lithographic patterning of building blocks, e.g., ZnO, BaTiO3, CdS, lipid membrane, conductive polymers, colloids, and liquid crystals. The entire process reveals new interfacial chemistry suitable for inorganic metal oxide and its important versatile implications for low-cost fabrication of large-area flat and flexible optical/electronic/biorelated devices.

12.
Phys Chem Chem Phys ; 16(44): 24235-43, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25293584

RESUMO

The fragmentation products of the ε-carbon-centered radical cations [Y(ε)˙LG](+) and [Y(ε)˙GL](+), made by 266 nm laser photolysis of protonated 3-iodotyrosine-containing peptides, are substantially different from those of their π-centered isomers [Y(π)˙LG](+) and [Y(π)˙GL](+), made by dissociative electron transfer from ternary metal-ligand-peptide complexes. For leucine-containing peptides the major pathway for the ε-carbon-centered radical cations is loss of the side chain of the leucine residue forming [YG(α)˙G](+) and [YGG(α)˙](+), whereas for the π-radicals it is the side chain of the tyrosine residue that is lost, giving [G(α)˙LG](+) and [G(α)˙GL](+). The fragmentations of the product ions [YG(α)˙G](+) and [YGG(α)˙](+) are compared with those of the isomeric [Y(ε)˙GG](+) and [Y(π)˙GG](+) ions. The collision-induced spectra of ions [Y(ε)˙GG](+) and [YGG(α)˙](+) are identical, showing that interconversion occurs prior to dissociation. For ions [Y(ε)˙GG](+), [Y(π)˙GG](+) and [YG(α)˙G](+) the dissociation products are all distinctly different, indicating that dissociation occurs more readily than isomerization. Density functional theory calculations at B3LYP/6-31++G(d,p) gave the relative enthalpies (in kcal mol(-1) at 0 K) of the five isomers to be [Y(ε)˙GG](+) 0, [Y(π)˙GG](+) -23.7, [YGG(α)˙](+) -28.7, [YG(α)˙G](+) -31.0 and [Y(α)˙GG](+) -38.5. Migration of an α-C-H atom from the terminal glycine residue to the ε-carbon-centered radical in the tyrosine residue, a 1-11 hydrogen atom shift, has a low barrier, 15.5 kcal mol(-1) above [Y(ε)˙GG](+). By comparison, isomerization of [Y(ε)˙GG](+) to [YG(α)˙G](+) by a 1-8 hydrogen atom migration from the α-C-H atom of the central glycine residue has a much higher barrier (50.6 kcal mol(-1)); similarly conversion of [Y(ε)˙GG](+) into [Y(π)˙GG](+) has a higher energy (24.4 kcal mol(-1)).


Assuntos
Radicais Livres/química , Oligopeptídeos/química , Fragmentos de Peptídeos/química , Isomerismo , Simulação de Dinâmica Molecular , Estrutura Molecular , Fotólise , Espectrometria de Massas por Ionização por Electrospray , Termodinâmica
13.
Colloids Surf B Biointerfaces ; 234: 113739, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219640

RESUMO

Browning has many important implications with nutrition and the shelf life of foods. Mitigating browning is of particular interest in food chemistry. The addition of antioxidants has been a common strategy to extend shelf life of drug and food products. In this work, we report a microfluidic technology for encapsulation of three common food additives (potassium metathionite (PMS), curcumin (CCM), and ß-carotene (ß-Car)) into nano-formulations using low-cost and readily available materials such as shellac. The food additives encapsulated nanoparticles provide a microenvironment that can prevent oxidation during daily storage. The results showed that the produced nanoparticles had a narrow size distribution with an average size of around 100 nm, were stable at conventional storage conditions (4 ºC) for 18 weeks, and had sustained release ability at 37 ºC, pH= 7.8, 160 rpm. In addition, further experiments showed that the formulation of hydrophobic additives, such as CCM and ß-Car did not only improve their bioavailability but also allowed for the encapsulation of a combination of ingredients. In addition, the antioxidants loaded nanoparticles demonstrated good biocompatibility, low toxicity to human cells. The longer release time of encapsulated food additives increases shelf life of foods and enhances consumer purchase preferences, which not only saves costs but also reduces waste. In summary, this study shows that such antioxidant-loaded nanoparticles provide a promising strategy in extending the shelf life of food products.


Assuntos
Antioxidantes , Nanopartículas , Humanos , Antioxidantes/farmacologia , Antioxidantes/química , Aditivos Alimentares , Microfluídica , Alimentos , Nanopartículas/química
14.
ACS Omega ; 9(19): 21097-21115, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38764674

RESUMO

The lacustrine shale of the Shahezi Formation in the Songliao Basin has obvious organic matter enrichment characteristics and great potential for oil and gas resources. At present, the understanding of the sedimentary paleoenvironment and organic matter enrichment characteristics of the lacustrine shale of the Shahezi Formation is relatively weak. Therefore, taking the international continental scientific drilling Program (ICDP) borehole Songke-2 (SK-2) with continuous and whole Shahezi cores as the research object, combined with organic geochemistry, elemental geochemistry, and logging data, the sedimentary paleoenvironment and organic matter enrichment mechanism were studied. The results show that the organic matter of Shahezi shale is generally in the high to over mature stage. The kerogen type of organic matter is mainly II2-III. The organic matter is mainly derived from the lake basin's own algae and terrestrial higher plants. The total organic carbon (TOC) content of Shahezi shale is relatively high, and the TOC is mainly distributed between 1% and 2%. The Shahezi Formation is dominated by clay shale and siliceous shale, and experienced moderate chemical weathering during deposition. According to the analysis of organic geochemistry and elemental geochemistry data, the paleoenvironment of organic matter deposition in Shahezi shale was dominated by warm and humid climate in the early stage, and then experienced multiple cooling and arid periods. The climate type turned to semihumid-semiarid, with stable terrigenous debris input, low deposition rate, brackish water salinity and oxygen-rich-oxygen-poor water environment. The sedimentary period of Shahezi Formation is in the Cretaceous oceanic anoxic Aptian-Albian stage. During the oceanic anoxic event, the anoxic sedimentary environment and the frequent volcanic activity have an important impact on the organic matter enrichment. The oceanic anoxic event and volcanic activity are the main causes of water body hypoxia in the lake basin. The nutrients brought by volcanic activity are also one of the reasons for promoting the growth of lake basin organisms, creating good conditions for organic matter enrichment. The enrichment of organic matter in Shahezi Formation is the result of the interaction and coupling of various factors such as paleoclimate, paleoenvironment, paleoproductivity, water environment, terrestrial input, and major geological events. And, the organic matter enrichment model of Shahezi Formation shale is established.

15.
Zhonghua Zhong Liu Za Zhi ; 35(2): 94-7, 2013 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-23714661

RESUMO

OBJECTIVE: To explore the relationship between epidermal growth factor receptor (EGFR) gene expression and radiosensitivity of non-small-cell lung cancer (NSCLC) cells. METHODS: EGFR sequence-specific double-stranded RNA (dsRNA-EGFR) was chemically synthesized. NSCLC cell line SPC-A1 was transfected with dsRNA-EGFR formulated with Lipofectamine 2000. Western blot and real-time PCR were used to determine the EGFR mRNA and protein expression, respectively. Colony inhibition test was adopted to observe the radiosensitizing effect. To establish the nude mouse tumor models, calculate the tumor growth inhibition rate and make the tumor growth curve by measuring its size and weight. RESULTS: EGFR mRNA levels were 1.51 ± 0.22, 1.38 ± 0.15 and 0.45 ± 0.11 in the control group, dsRNA-unrelated group and dsRNA-EGFR group, respectively (F = 482.7, P < 0.01). The contents of EGFR protein were 2340.87 ± 10.99, 2231.85 ± 35.66 and 832.03 ± 39.13 in the control group, dsRNA-unrelated group and dsRNA-EGFR group, respectively (F = 263.3, P < 0.05). Compared with the control group, dsRNA-EGFR sequence specifically decreased the expressions of EGFR mRNA by 70.2% and EGFR protein by 64.5%. The colony inhibition rates of the control group, dsRNA-unrelated combined with radiotherapy group and dsRNA-EGFR combined with radiotherapy group were 9.3%, 12.5% and 65.5%, and the tumor growth inhibition rates were 21.3%, 24.4% and 64.2%, respectively. The combination of dsRNA-EGFR and radiotherapy significantly inhibited the tumor growth in vitro and in vivo. CONCLUSIONS: DsRNA-EGFR shows an apparent inhibitory effect on the expression of EGFR mRNA and protein of NSCLC cells, effectively inhibit the tumor growth in vivo, and enhance the radiosensitivity of NSCLC.


Assuntos
Adenocarcinoma/metabolismo , Proliferação de Células/efeitos da radiação , Receptores ErbB/metabolismo , Neoplasias Pulmonares/metabolismo , Carga Tumoral/efeitos da radiação , Adenocarcinoma/patologia , Adenocarcinoma/radioterapia , Animais , Linhagem Celular Tumoral , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , RNA de Cadeia Dupla/genética , RNA Mensageiro/metabolismo , Tolerância a Radiação , Distribuição Aleatória , Transfecção
16.
Zhonghua Jie He He Hu Xi Za Zhi ; 36(5): 337-40, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-24047806

RESUMO

OBJECTIVE: To explore the endoscopic features of patients with unexplained pleural effusion, and to evaluate the diagnostic value of medical thoracoscopy. METHODS: A retrospective analysis of 2380 patients with unexplained pleural effusion (1320 males and 1060 females; age 15-94 years) in Shandong Provincial Hospital from 1992 to 2011 were performed .The diagnosis was confirmed by medical thoracoscopy. RESULTS: The endoscopic findings of malignant pleural effusion mostly showed nodules of varying sizes. The nodules could be grape-like, cauliflower-like, fused into masses, or diffused small nodules . The appearance of cancerous nodules was more diversified compared to tuberculous nodules. Tuberculous pleurisy was manifested as diffuse pleural congestion and miliary changes, multiple small gray-white nodules, fibrin deposition and adhesion in the pleural cavity, pleural thickening and loculation . The pathological diagnosis was as follows: pleural metastases in 899 (37.8%), primary pleural mesothelioma in 439 (18.4%), tuberculous pleurisy in 514 (21.6%), non-specific inflammation in 226 (9.5%), empyema in 190 (8.0%), hepatic pleural effusion in 36 (1.5%) and pleural effusion of unknown causes in 76 (3.2%) cases. The diagnostic positive rate of medical thoracoscopy was 96.8%. No serious complications were observed. CONCLUSION: Medical thoracoscopy is a relatively safe procedure and has an important application value in the diagnosis of unexplained pleural effusion.


Assuntos
Pleura/patologia , Derrame Pleural/diagnóstico , Neoplasias Pleurais/diagnóstico , Toracoscopia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Dor no Peito/epidemiologia , Dor no Peito/etiologia , Diagnóstico Diferencial , Feminino , Febre/epidemiologia , Febre/etiologia , Humanos , Masculino , Mesotelioma/complicações , Mesotelioma/diagnóstico , Mesotelioma/patologia , Pessoa de Meia-Idade , Metástase Neoplásica , Derrame Pleural/etiologia , Derrame Pleural/patologia , Derrame Pleural Maligno/diagnóstico , Derrame Pleural Maligno/etiologia , Derrame Pleural Maligno/patologia , Neoplasias Pleurais/complicações , Neoplasias Pleurais/patologia , Estudos Retrospectivos , Toracoscopia/efeitos adversos , Tuberculose Pleural/complicações , Tuberculose Pleural/diagnóstico , Tuberculose Pleural/patologia , Adulto Jovem
17.
J Clin Lab Anal ; 25(5): 324-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21919065

RESUMO

BACKGROUND: Microalbuminuria is an indicator of kidney damage and a risk factor for the progression kidney disease, cardiovascular disease, and so on. Therefore, accurate and precise measurement of urinary albumin is critical. However, there are no reference measurement procedures and reference materials for urinary albumin. METHODS: Nephelometry, turbidimetry, colloidal gold method, radioimmunoassay, and chemiluminescence immunoassay were performed for methodological evaluation, based on imprecision test, recovery rate, linearity, haemoglobin interference rate, and verified reference interval. Then we tested 40 urine samples from diabetic patients by each method, and compared the result between assays. RESULTS: The results indicate that nephelometry is the method with best analytical performance among the five methods, with an average intraassay coefficient of variation (CV) of 2.6%, an average interassay CV of 1.7%, a mean recovery of 99.6%, a linearity of R=1.00 from 2 to 250 mg/l, and an interference rate of <10% at haemoglobin concentrations of <1.82 g/l. The correlation (r) between assays was from 0.701 to 0.982, and the Bland-Altman plots indicated each assay provided significantly different results from each other. CONCLUSION: Nephelometry is the clinical urinary albumin method with best analytical performance in our study.


Assuntos
Albuminúria/urina , Urinálise/métodos , Urinálise/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Albuminas/análise , Feminino , Coloide de Ouro/química , Hemoglobinas/análise , Hemoglobinúria/urina , Humanos , Imunoensaio , Masculino , Pessoa de Meia-Idade , Nefelometria e Turbidimetria , Padrões de Referência , Análise de Regressão , Reprodutibilidade dos Testes
18.
Chem Commun (Camb) ; 57(54): 6612-6615, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34116566

RESUMO

Negative ion mode paper spray mass spectrometry (PS-MS) suffers from intense background noise and unstable MS signal. For the first time, we reported fluorinated boron nitride nanosheet (h-FBN) assisted negative ion PS-MS for the detection of a series of molecules. We demonstrated that the introduction of h-FBN can greatly improve the detection sensitivity and signal stability in the negative ion mode.


Assuntos
Compostos de Boro/química , Halogenação , Limite de Detecção , Espectrometria de Massas/métodos , Papel , Nanoestruturas/química , Razão Sinal-Ruído
19.
Medicine (Baltimore) ; 100(6): e24640, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33578585

RESUMO

ABSTRACT: Lung cancer is the most common type of cancer worldwide with a high mortality rate. The specific tyrosine kinase inhibitors of epidermal growth factor receptor (EGFR) have made enormous strides in non-small-cell lung cancer (NSCLC) treatment. The novel systemic immune-inflammation index (SII), a parameter that integrates lymphocytes, neutrophils, and platelets, has been found to play the vital role of a marker for predicting survival and recrudescence in various tumors.We retrospectively examined 102 patients with different EGFR-mutant lung adenocarcinomas. Survival analysis was performed using the Kaplan-Meier method with the log-rank test. Cut-off points were identified using the receiver operating characteristic curves with the maximum log-rank values. The Cox proportional hazards regression, expressed as p value, hazards regression, and 95% confidence interval, was conducted to assess the prognostic values of variables in overall survival (OS)/ progression-free survival (PFS).Lower SII was associated with prolonged survival in patients with different EGFR mutant lung adenocarcinomas in both variable and multivariable analyses.SII before treatment was a powerful indicator for the PFS and OS of patients who received the first-generation EGFR-TKI.


Assuntos
Adenocarcinoma/mortalidade , Inflamação , Neoplasias Pulmonares/mortalidade , Recidiva Local de Neoplasia/mortalidade , Índice de Gravidade de Doença , Adenocarcinoma/sangue , Adenocarcinoma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , China , Receptores ErbB/genética , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Mutação , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/genética , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos
20.
Blood Cells Mol Dis ; 45(4): 313-6, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20934357

RESUMO

The aim of this study was to investigate whether a single nucleotide polymorphism (SNP) +874T/A of interferon-gamma (IFN-γ) correlates with response to immunosuppressive therapy. Amplification refractory mutation system-polymerase chain reaction was used to amplify the polymorphic segments of the IFN-γ +874T/A gene in the samples obtained from 54 patients with aplastic anemia and 51 healthy adults. Further, enzyme linked immunosorbent assay was used to assay IFN-γ levels in the blood plasma of 35 patients with severe aplastic anemia before immune suppression therapy and 20 healthy blood donors. The results showed that the frequency of IFN-γ +874 TT genotype in patients with aplastic anemia was significantly higher than the corresponding frequency in the healthy adults (42.6% vs. 17.6%, χ(2)=13.78, p=0. 01). The response rate in severe aplastic anemia patients with increased IFN-γ levels in the blood plasma was higher than that in severe aplastic anemia patients with decreased IFN-γ levels in the blood plasma (73.7% vs. 25.0%, p<0.05). Of the 35 patients with severe aplastic anemia, 15 showed the IFN-γ +874 TT genotype, whereas response in 11 patients, the high response rate was significantly in the favor of the IFN-γ +874 TT genotype (73.3% vs. IFN-γ +874 non-TT 35%, p<0.05). In conclusion, the IFN-γ +874T/A gene polymorphism may be correlated with response to immunosuppressive therapy.


Assuntos
Anemia Aplástica/genética , Imunossupressores/farmacologia , Interferon gama/genética , Farmacogenética/métodos , Polimorfismo de Nucleotídeo Único , Adolescente , Idoso , Idoso de 80 Anos ou mais , Anemia Aplástica/tratamento farmacológico , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Terapia de Imunossupressão , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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