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1.
J Colloid Interface Sci ; 673: 333-345, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38878368

RESUMO

Ultralight graphene aerogels have gained extensive recognition in the impact protection field. However, attaining both elasticity and durability at low material density is challenging due to their intrinsic conflicts. Inspired by the mantis ootheca, we present a simultaneous improvement in the elasticity, durability, and density restrictions of ultralight graphene aerogels via constructing a multiscale honeycomb microstructure (MHM) within the graphene skeleton. This approach enables resulting graphene aerogel to achieve a strength per unit volume of 284.6 cm3 mg-1, the ability to recover its shape within 10 ms after an impact at 3.569 m/s, and maintain 97.2 % of its sample height after 20,000 cycles at 90 % strain. The operand analyses and calculation results reveal that the MHM structure facilitates this aerogel's dual-stage stress transfer pathway. Initially, the macroscale honeycomb structure (millimeter-scale) of the graphene aerogels bear and transmit stress to the surrounding regions, followed by the microscale honeycomb structure (micron-scale) deformation to convert stress kinetic energy into elastic potential energy. This two-stage stress transition mechanism of the MHM structure can effectively mitigate excessive local stress and suppress strain localization, thus providing remarkable elasticity and durability. Ultimately, the obtained graphene aerogel demonstrates promising applications as a fall height detection device and impact protective material.

2.
Hemoglobin ; 48(2): 71-78, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38632980

RESUMO

To explore a noninvasive method for diagnosis of SEA-thalassemia and to investigate whether the regional factors affect the accuracy of this method. The method involved using a public database and bioinformatics software to construct parental haplotypes for proband and predicting fetal genotypes using relative haplotype dosage. We screened and downloaded sequencing data of couples who were both SEA-thalassemia carriers from the China National Genebank public data platform, and matched the sequencing data format with that of the reference panel using Ubuntu system tools. We then used Beagle software to construct parental haplotypes, predicted fetal haplotypes by relative haplotype dosage. Finally, we used Hidden Markov Model and Viterbi algorithm to determine fetal pathogenic haplotypes. All noninvasive fetal genotype diagnosis results were compared with gold standard gap-PCR electrophoresis results. Our method was successful in diagnosing 13 families with SEA-thalassemia carriers. The best diagnostic results were obtained when Southern Chinese Han was used as the reference panel, and 10 families showed full agreement between our noninvasive diagnostic results and the gap-PCR electrophoresis results. The accuracy of our method was higher when using a Chinese Han as the reference panel for haplotype construction in the Southern Chinese Han region as opposed to Beijing Chinese region. The combined use of public databases and relative haplotype dosage for diagnosing SEA-thalassemia is a feasible approach. Our method produces the best noninvasive diagnostic results when the test samples and population reference panel are closely matched in both ethnicity and geography. When constructing parental haplotypes with our method, it is important to consider the effect of region in addition to population background alone.


Assuntos
Haplótipos , Humanos , Feminino , Gravidez , Talassemia/genética , Talassemia/diagnóstico , Bases de Dados Genéticas , Diagnóstico Pré-Natal/métodos , Teste Pré-Natal não Invasivo/métodos , Genótipo , China/epidemiologia
3.
Anal Chem ; 96(10): 4299-4307, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38414258

RESUMO

To boost the enzyme-like activity, biological compatibility, and antiaggregation effect of noble-metal-based nanozymes, folic-acid-strengthened Ag-Ir quantum dots (FA@Ag-Ir QDs) were developed. Not only did FA@Ag-Ir QDs exhibit excellent synergistic-enhancement peroxidase-like activity, high stability, and low toxicity, but they could also promote the lateral root propagation of Arabidopsis thaliana. Especially, ultratrace cysteine or Hg2+ could exclusively strengthen or deteriorate the inherent fluorescence property with an obvious "turn-on" or "turn-off" effect, and dopamine could alter the peroxidase-like activity with a clear hypochromic effect from blue to colorless. Under optimized conditions, FA@Ag-Ir QDs were successfully applied for the turn-on fluorescence imaging of cysteine or the stress response in cells and plant roots, the turn-off fluorescence monitoring of toxic Hg2+, or the visual detection of dopamine in aqueous, beverage, serum, or medical samples with low detection limits and satisfactory recoveries. The selective recognition mechanisms for FA@Ag-Ir QDs toward cysteine, Hg2+, and dopamine were illustrated. This work will offer insights into constructing some efficient nanozyme sensors for multichannel environmental analyses, especially for the prediagnosis of cysteine-related diseases or stress responses in organisms.


Assuntos
Mercúrio , Pontos Quânticos , Pontos Quânticos/toxicidade , Cisteína , Dopamina , Ácido Fólico , Imagem Óptica , Peroxidases , Raízes de Plantas
4.
Biochem Genet ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38416273

RESUMO

Chinese mitten crab, Eriocheir sinensis, is a decapod crustacean with a special, non-condensated nucleus in the sperm. Studies have shown that the nuclear compact state of male germ cells during the spermatogenesis is closely related to histone modification. To explore the possible role of histone acetyltransferase 1 (HAT1) in the chromatin organization during the E. sinensis spermatogenesis, we took the testis tissues of both adult and juvenile crabs as the materials of study and analyzed the biological functions of HAT1 by whole transcriptome sequencing and bioinformatics, then further analyzed the expression and distribution of HAT1 using the methods of RT-qRCR, western blotting, and immunofluorescence location. The results showed that HAT1 is an alkaline-unstable hydrophilic protein. It was predicted to interact with a variety of histones and chromosome assembly proteins, including Asf1b, Chaf1b, and Hist1h3f, and is involved in many biological functions pertaining to chromatin dynamics such as chromatin organization, DNA dependent nucleosome assembly, DNA conformational changes, and so on. HAT1 was up-regulated in the adult testes compared to the juvenile (n = 3, P < 0.05). HAT1 was mainly located in the nuclei of male germ cells of E. sinensis. As spermatogenesis proceeded, the expression of HAT1 decreased and even disappeared in the nuclei (n = 3, P < 0.05). HAT1 is an important player in histone acetylation, which facilitates chromatin alteration in a three-dimensional conformation. The expression of HAT1 in different male germ cells might indicate the chromatin dynamics at the diversity stages of spermatogenesis. The high expression of HAT1 at the early stages of E. sinensis spermatogenesis hints the active involvement in chromatin organization, while its progressively reduced expression accompanied by the progression of spermatogenesis suggests a relatively gradual stabilization and stereotyping of chromatin. As for the disappearance of HAT1 in mature sperm with non-condensed nuclei, the reduction in histones targeted by HAT1 or histone acetylation may be an important initiator.

5.
PeerJ ; 11: e15547, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37334119

RESUMO

Background: The sperm of Chinese mitten crab (Eriocheir sinensis) have special noncondensed nuclei. The formation and stability of the special nuclei are closely related to the correct folding of proteins during spermatogenesis. P4HB plays a key role in protein folding, but its expression and role in the spermatogenesis of E. sinensis are unclear. Objective: To investigate the expression and distribution characteristics of P4HB in the spermatogenesis of E. sinensis as well as its possible role. Methods: The testis tissues of adult and juvenile E. sinensis were used as materials. We utilized a variety of techniques, including homology modeling, phylogenetic analysis, RT-qPCR, western blotting, and immunofluorescence staining to predict the protein structure and sequence homology of P4HB, analyze its expression in the testis tissues, and localize and semi-quantitatively assess its expression in different male germ cells. Results: The sequence of P4HB protein in E. sinensis shared a high similarity of 58.09% with the human protein disulfide isomerase, and the phylogenetic tree analysis indicated that the protein sequence was highly conserved among crustaceans, arthropods, and other animals species. P4HB was found to be expressed in both juvenile and adult E. sinensis testis tissues, with different localization patterns observed all over the developmental stages of male germ cells. It was higher expressed in the spermatogonia, spermatocytes, and stage I spermatids, followed by the mature sperm than in the stage II and III spermatids. The subcellular localization analysis revealed that P4HB was predominantly expressed in the cytoplasm, cell membrane, and extracellular matrix in the spermatogonia, spermatocytes, stage I and stage II spermatids, with some present in specific regions of the nuclei in the spermatogonia. In contrast, P4HB was mainly localized in the nuclei of stage III spermatids and sperm, with little expression observed in the cytoplasm. Conclusion: P4HB was expressed in the testis tissues of both adult and juvenile E. sinensis, but the expression and localization were different in male germ cells at various developmental stages. The observed differences in the expression and localization of P4HB may be an essential factor in maintaining the cell morphology and structure of diverse male germ cells in E. sinensis. Additionally, P4HB expressed in the nuclei of spermatogonia, late spermatids, and sperm may play an indispensable role in maintaining the stability of the noncondensed spermatozoal nuclei in E. sinensis.


Assuntos
Sêmen , Testículo , Animais , Masculino , Filogenia , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Isomerases de Dissulfetos de Proteínas/metabolismo , Espermatogênese/genética , Espermatogônias/metabolismo , Braquiúros
6.
Hemoglobin ; 47(2): 80-84, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37247204

RESUMO

Thalassemia is a genetic disease that seriously affects the health of the fetus. At present, invasive prenatal diagnosis is the main method of thalassemia screening, but invasive prenatal diagnosis has the risk of fetal abortion. The discovery of cell-free fetal DNA (cffDNA) in the peripheral blood of pregnant women provides the possibility for non-invasive prenatal diagnosis (NIPD). Rapid and efficient capture of mutational information on cffDNA in maternal plasma can help prevent the birth of children with thalassemia major. Currently, strategies for cffDNA-based NIPD of thalassemia include the detection of paternal mutations in maternal plasma, detection of a proportion of wild and mutant alleles in maternal plasma, linkage disequilibrium single nucleotide polymorphism (SNP) based on pedigree probands, and prediction of fetal genotypes by bioinformatics combined with population information. Therefore, this paper will focus on the above aspects, in order to provide an essential reference to the prevention and treatment of thalassemia.


Assuntos
Ácidos Nucleicos Livres , Talassemia beta , Criança , Gravidez , Humanos , Feminino , DNA/genética , Diagnóstico Pré-Natal/métodos , Feto , Talassemia beta/genética
7.
BMC Genom Data ; 24(1): 4, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36782118

RESUMO

Cytoskeleton-related proteins are essential for cell shape maintenance and cytoskeleton remodeling. The spermatozoa of Eriocheir sinensis (Chinese mitten crab) have a unique cellular structure, and the mechanism of spermatozoal metamorphosis during the acrosome reaction is not well understood. In this study, the E. sinensis spermatozoa were induced using calcium ionophore A23187 to undergo the acrosome reaction in vitro, and the acrosome-reacting and fresh (non-reacting) spermatozoa were collected separately. The differential expression of cytoskeleton-related protein genes in acrosome-reacting and fresh spermatozoa of E. sinensis was analyzed by whole transcriptome sequencing and bioinformatics analysis, and PPI network and miRNA-mRNA regulation network were constructed to analyze their possible function and regulation mechanism. The results showed that numerous differentially expressed cytoskeleton-related protein genes, miRNAs and lncRNAs were found in acrosome-reacting and fresh spermatozoa of E. sinensis; 27 cytoskeleton-related protein genes were down regulated and 687 miRNAs were up regulated in acrosome-reacting spermatozoa; 147 miRNAs target these 27 cytoskeleton-related protein genes. In the PPI networks, RAC1, BCAR1, RDX, NCKAP1, EPS8, CDC42BPA, LIMK1, ELMO2, GNAI1 and OCRL were identified as hub proteins. These proteins are mainly involved in the regulation of cytoskeleton organization, actin cytoskeleton organization, microtubule skeleton organization and small GTPase-mediated signal transduction and other biological processes, and play roles in pathways such as actin cytoskeletal regulation and axon guidance. miR-9, miR-31 and two novel miRNAs in the miRNA-mRNA regulatory network are the core miRNAs targeting cytoskeleton-related protein genes. miR-9 targets and regulates OBSCN, CDC42BPA, ELMO2, BCAS3, TPR and OCRL; while miR-31 targets and regulates CDC42BPA and TPR. This study provides a theoretical basis for revealing the mechanism of acrosome reaction under the special spermatozoa morphology of E. sinensis.


Assuntos
Reação Acrossômica , Braquiúros , Proteínas do Citoesqueleto , MicroRNAs , Espermatozoides , Masculino , Reação Acrossômica/genética , Reação Acrossômica/fisiologia , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/análise , Proteínas do Citoesqueleto/metabolismo , Citoesqueleto/genética , MicroRNAs/genética , RNA Mensageiro/genética , Espermatozoides/metabolismo , Braquiúros/genética , Braquiúros/metabolismo
8.
Food Chem ; 408: 135259, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36566540

RESUMO

Conveniently and efficiently monitoring I- and Hg2+ in agricultural products or drinking beverages for the protection of human health is currently a great challenge. With this aim, a Ag-Pt bimetal quantum-dot nanozyme boosted by bioactive folic acid (FA@Ag-Pt QDs) was first developed for multichannel monitoring of I- and Hg2+ in this work using a two-step liquid-phase reduction method. Not only did the present FA@Ag-Pt QDs possess superior peroxidase-like activity with Michaelis constant (Km) and maximal reaction rate (Vmax) of 0.01 mM/2.95 × 10-8 M·s-1 and 1.15 mM/3.88 × 10-8 M·s-1, respectively, trace Hg2+ or I- could exclusively alter their enzyme-mimic performance with obvious color changes from blue to colorless or dark blue. I- could also strengthen the inherent fluorescence property of FA@Ag-Pt QDs. When applied for visual monitoring of I- and Hg2+ in real beverages or iodine-containing agricultural products, the detection recoveries were 93.9 %-105.3 % and 96.8-104.3 % with low detection limits of 6.56 × 10-8 mol/L and 4.00 × 10-10 mol/L (S/N = 3), respectively. The recovery and detection limit for fluorescent detection of I- were 95.8 %-104.1 % and 1.75 × 10-8 mol/L (S/N = 3), respectively. The mechanisms driving the improved peroxidase-like activity of FA@Ag-Pt QDs and their selective monitoring of Hg2+ and I- were illustrated in detail. The proposed FA@Ag-Pt QDs will act as an efficient sensor for the practical multichannel monitoring of Hg2+ and I-, with superior catalytic signal amplification.


Assuntos
Mercúrio , Pontos Quânticos , Humanos , Colorimetria , Limite de Detecção , Bebidas , Corantes , Mercúrio/análise , Peroxidases
9.
Mikrochim Acta ; 190(1): 1, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36456757

RESUMO

A portable sensor for visual monitoring of Fe2+ and H2O2, two-dimensional Co3O4 modified by nano-IrO2 (IrO2@2D Co3O4) was prepared in this work, for the first time, with the help of microwave radiation at 140 °C, which was further stabilized onto common test strips. The present IrO2@2D Co3O4 possessed superior dual-function enzyme-like activity with low toxicity and excellent biocompatibility. Especially, trace Fe2+ and H2O2 could exclusively alter their enzyme-like catalytic activity with discriminating hyperchromic or hypochromic effect, i.e., from blue to colorless or to dark blue for both IrO2@2D Co3O4 dispersion and its functionalized test strips. The linear regression equations were A652 = 0.5940 - 0.00041 cFe2+ (10-8 M, R2 = 0.9927) for Fe2+ and ∆A652 = 0.0023 cH2O2 + 0.00025 (10-7 M, R2 = 0.9982) for H2O2, respectively. When applied to visual monitoring of aqueous Fe2+ and intercellular H2O2, the recoveries were 101.2 ~ 102.5% and 95.8 ~ 103.7% with detection limits of 1.25 × 10-8 mol/L and 1.02 × 10-7 mol/L, respectively, far below the permitted values in drinking water set by the World Health Organization. The mechanisms for the enhancing enzyme-mimetic activity of IrO2@2D Co3O4 and its selective responses to Fe2+ and H2O2 were investigated in detail.


Assuntos
Peróxido de Hidrogênio , Micro-Ondas , Cobalto , Modelos Lineares
10.
Mikrochim Acta ; 189(9): 314, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35925496

RESUMO

To enhance the peroxidase-like performance and its application in detection of toxic o-aminophenol (o-AP), a kind of bimetal Cu-Zn oxide-based mesoporous nanosphere (Cu2/3Zn1/3O PNPs) was constructed under microwave-radiation conditions. Its mesoporous microstructure and peroxidase-like catalytic activity were investigated in detail. The results showed that Cu2/3Zn1/3O PNPs possessed a high specific surface area of 34.89 m2g-1 and a well-distributed mesoporous size of approximate 6.07 nm, which endowed the superior peroxidase-like performance. The material catalyzes the oxidization of 3,3',5,5'-tetramethylbenzidine (TMB) with Km/Vmax of 0.104 mM/3.79 × 10-8 M·s-1 in the presence of H2O2. Especially o-AP could exclusively deteriorate the characteristic UV-Vis absorbance intensity at 653 nm (A653) of the Cu2/3Zn1/3O PNPs-TMB-H2O2 system with obvious color change from blue to colorless. Under the optimal conditions, the effect of some interfering substances was low and the limit of detection (LOD) for o-AP was 1.65 × 10-8 mol/L (S/N = 3). When applied to the colorimetric detection of o-AP in practice, the recovery was between 96.1 and 107.2% with R.S.D. less than 2.04%. The mechanism of synergic-enhancement peroxidase-mimic activity of Cu2/3Zn1/3O PNPs and its exclusive colorimetric response to o-AP were proposed as well.


Assuntos
Nanosferas , Óxidos , Aminofenóis , Peróxido de Hidrogênio/química , Peroxidase/química , Zinco
11.
Anal Bioanal Chem ; 414(22): 6611-6620, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35836011

RESUMO

Dopamine (DA) is an important neurotransmitter; however, any excess or deficiency of DA will cause several diseases in humans. To monitor DA efficiently and conveniently, a Ag nanozyme strengthened by bioactive folic acid (FA@AgNPs) was developed by homogeneous redox assembly. After the microstructure and performance were characterized in detail, it was noted that the proposed FA@AgNPs possessed superior peroxidase-like activity due to the ultra-small Ag nanoparticles and multiple amino, hydroxyl, and aromatic rings in FA. FA@AgNPs accelerated the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) with a low Michaelis constant (Km) and high maximal reaction rate (Vmax). Importantly, the characteristic absorbance intensity of FA@AgNPs-TMB-H2O2 at 652 nm (A652) was exclusively deteriorated in the presence of trace DA, accompanied by a visual color change from blue to colorless. Under the optimized conditions (pH 4.0, 300 µL 1.5 mM TMB, 300 µL 1.0 M H2O2 and incubated for 30 min at room temperature), there expressed an excellent linear relationship between lgA0/A652 and cDA from 1.0 ×10-8 to 6.67×10-6 mol/L with a low limit detection of 7.1×10-10 mol/L (S/N=3). When applied for monitoring of DA in real fruit juice and pharmaceutical samples, the recovery was between 96.6% and 104.9%, with RSD less than 2.2%. The enhanced peroxidase-like activity of the FA@AgNP system and its selective recognition mechanism for DA are also proposed.


Assuntos
Dopamina , Nanopartículas Metálicas , Antioxidantes , Colorimetria , Ácido Fólico , Humanos , Peróxido de Hidrogênio/química , Nanopartículas Metálicas/química , Peroxidase/química , Peroxidases , Prata
12.
Org Lett ; 24(10): 2059-2063, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35262358

RESUMO

A photocatalyzed transformation from sulfinic acids to sulfoxides under visible-light irradiation in the presence of N-heterocyclic carbene is established. Various alkyl groups from four-substituted Hantzsch esters or Meyer nitriles are smoothly converted to the corresponding sulfoxides through a radical coupling pathway in the presence of 1,1-carbonyldiimidazole. This method allows sulfoxide synthesis to refrain from relying on the oxidation of sulfides and provides an alternative route for the preparation of sulfoxides.

13.
J Hazard Mater ; 409: 125019, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33421875

RESUMO

To enlarge the perspective of nanozyme, 2-dimensional Co3O4 stabilizing Rh nano composite (2D Co3O4@Rh NC) was identified and developed first by one-pot surfactant-aided oxido-reduction. By virtue of the synergetic-reinforcing oxidase activity between 2D Co3O4 substrate and Rh nano particles, the obtained 2D Co3O4@Rh NC could catalyze the oxidation of chromogenic substrate 3,3',5,5,'-tetramethylbenzidine (TMB) to blue oxTMB with quite a low Michaelis-Menten constant (Km) of 0.018 mM and a quick vmax of 6.45 × 10-8 M s-1, expressing superior oxidase-like catalysis with a wide temperature range from 20 to 60 °C. Importantly, either bioactive urea or toxic p-aminophenol (p-Ap) could exclusively alter the existed state of oxTMB with differentiable color changes. Under the optimized conditions, 2D Co3O4@Rh NC was successfully applied for ratiometric colorimetric sensing urea and p-Ap in environmental water, soil and urine samples with low detection limits (1.1 µM for urea and 0.68 µM for p-Ap) and satisfactory recoveries (96.0-105.8%). The synergetic enhanced oxidase-like activity of 2D Co3O4@Rh NC and the different reaction mechanisms of the 2D Co3O4@Rh NC-TMB system to urea and p-Ap were investigated. Not only does the work provide an efficient way for sensing organic pollution of p-Ap, it will offer an efficient potential for diagnosing urea-related diseases on clinical medical testing in future.


Assuntos
Cobalto , Oxirredutases , Aminofenóis , Colorimetria , Ureia
14.
Sci Rep ; 10(1): 14811, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908181

RESUMO

Since the late 1970s, sea surface temperatures (SSTs) have exhibited greater responses to global warming in the offshore area of China and adjacent seas (offshore China) than in the global ocean. This study identified a surface warming reacceleration in offshore China since 2011, following a well-known interdecadal shift from offshore surface warming to cooling in 1998. During the warming reacceleration period, the rate of increase in offshore China SSTs was twice the mean rate of global ocean surface warming, and the significantly warming area was primarily in the north, especially in the East China Sea. Concurrent with the ascending phase of the Interdecadal Pacific Oscillation, a large area of positive sea level pressure anomalies developed over the tropical Pacific. Accordingly, the surface southerly wind anomalies contributed to the recent surface warming in offshore China, especially in the East China Sea. With greater changes in the warming rate, the spatial mode of the circulation anomalies over East Asia and the western Pacific has shifted westward and has exerted more inshore influence during the recent warming reacceleration period than during the previous periods.

15.
PeerJ ; 8: e8680, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32219019

RESUMO

BACKGROUND: The tumor microenvironment (TM) in close contact with cancer cells is highly related to tumor growth and cancer metastasis. This study is to explore the biogenesis mechanism of a secondary hepatocellular carcinoma (HCC) based on the function of RNA binding proteins (RBPs)-encoding genes in the physiological microenvironment (PM). METHODS: The healthy and HCC mice were used to isolate the PM, pre-tumor microenvironment (PTM), and TM. The samples were analyzed using the technology of RNA-seq and bioinformatics. The differentially expressed RBPs-encoding genes (DERs) and differentially expressed DERs-associated genes (DEDs) were screened to undergo GO and KEGG analysis. RESULTS: 18 DERs and DEDs were identified in the PTM vs. PM, 87 in the TM vs. PTM, and 87 in the TM vs. PM. Those DERs and DEDs participated in the regulation of gene expression at the levels of chromatin conformation, gene activation and silencing, splicing and degradation of mRNA, biogenesis of piRNA and miRNA, ribosome assemble, and translation of proteins. CONCLUSION: The genes encoding RBPs and the relevant genes are involved in the transformation from PM to PTM, then constructing the TM by regulating protein synthesis. This regulation included whole process of biological genetic information transmission from chromatin conformation to gene activation and silencing to mRNA splicing to ribosome assemble to translation of proteins and degradation of mRNA. The abnormality of those functions in the organic microenvironments promoted the metastasis of HCC and initiated the biogenesis of a secondary HCC in a PM when the PM encountered the invasion of cancer cells.

16.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117451, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31404759

RESUMO

To illustrate the impact of molecular structure, especially heterocycle unit, on the sensing performance, two kinds of π-conjugated molecules containing aromatic heterocyclic (Dye 1) and aromatic ring (Dye 2) were identified and compared each other. Even with similar structures, they possessed quite different spectral and colorimetric responses to F-, Cl-, Br-, I-, NO3-, HSO4-, H2PO4-, ClO4- and CH3COO-, etc. The reason might result from the difference in withdraw-electron ability of aromatic and heterocyclic rings, which would lead to different acidity of active H in the target π-conjugated molecules. In acidic aqueous, Dye 1 expressed a reversible ratiometric-colorimetric response to F-, accompanying with a visual color change from bright yellow to purple, a nice linear range of 2.0-35.0 × 10-6 mol/L and a low detection limit of 1.60 × 10-7 mol/L. While Dye 2 did not react with any anion due to its weak acidity of active hydrogen. Under the optimized conditions, Dye 1 was successfully applied for colorimetric or naked-eye detection of F- in environmental water, tea and toothpaste samples with RSD ≤ 3.1%. The recognition mechanism for Dye 1 to F- was confirmed to be deprotonation one with a 1:1 binding stoichiometry.

17.
Br J Radiol ; 91(1084): 20170421, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29308923

RESUMO

OBJECTIVE: To determine whether intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) derived parameters can be associated with tumour stage of oesophageal squamous cell carcinoma (SCC). METHODS: 60 patients with resectable oesophageal SCC and 20 healthy individuals underwent oesophageal DWI-using multi b-values with a 3.0 T MR system. Pure diffusion coefficient (D), perfusion-related incoherent microcirculation (D*), microvascular volume fraction (f) and apparent diffusion coefficient (ADC) were measured on DWI. Statistical analyses were performed to determine associations of DWI-derived parameters with T-stage. RESULTS: ADC (r = -0.842), D (r = -0.729), D* (r = -0.301) and f (r = -0.817) were negatively correlated with T-stage of oesophageal SCC (all p < 0.01), and the multinominal regression analyses revealed that IVIM-derived parameters including D (p = 0.038; odds ratio <1) and f (p < 0.001; odds ratio <1) were associated with T-stage. The Mann-Whitney U tests with Bonferroni correction showed that D, f and ADC could discriminate oesophageal SCC, especially T1-staged tumour, from normal oesophagus (all p < 0.05) while D* could not (p > 0.05). By receiver operating characteristic analyses, f could be the best indicator for detecting oesophageal SCC with an area under receiver operating characteristic (AUC) of 0.964, especially T1-staged cancer with an AUC of 0.984, and for discriminating T1-stages between T0-1 and T2-3 with an AUC of 0.957, and between T0-2 and T3 with an AUC of 0.945 in comparison with any other DWI-derived parameter. CONCLUSIONS: IVIM derived parameters can be associated with T-stage of oesophageal SCC. Advances in knowledge (1) IVIM-derived parameters are negatively correlated with stage of oesophageal SCC. (2) Among IVIM-derived parameters, microvascular volume fraction helps detect and stage oesophageal SCC.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Idoso , Estudos de Casos e Controles , Carcinoma de Células Escamosas do Esôfago , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Estadiamento de Neoplasias , Estudos Retrospectivos
18.
Korean J Radiol ; 18(4): 674-681, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28670162

RESUMO

OBJECTIVE: To explore the association between the blood oxygenation T2* values of resectable esophageal squamous cell carcinomas (ESCCs) and tumor stages. MATERIALS AND METHODS: This study included 48 ESCC patients and 20 healthy participants who had undergone esophageal T2*-weighted imaging to obtain T2* values of the tumors and normal esophagi. ESCC patients underwent surgical resections less than one week after imaging. Statistical analyses were performed to identify the association between T2* values of ESCCs and tumor stages. RESULTS: One-way ANOVA and Student-Newman-Keuls tests revealed that the T2* value could differentiate stage T1 ESCCs (17.7 ± 3.3 ms) from stage T2 and T3 tumors (24.6 ± 2.7 ms and 27.8 ± 5.6 ms, respectively; all ps < 0.001). Receiver operating curve (ROC) analysis showed the suitable cutoff T2* value of 21.3 ms for either differentiation. The former statistical tests demonstrated that the T2* value could not differentiate between stages T2 and T3 (24.6 ± 2.7 ms vs. 27.8 ± 5.6 ms, respectively, p > 0.05) or between N stages (N1 vs. N2 vs. N3: 24.7 ± 6.9 ms vs. 25.4 ± 4.5 ms vs. 26.8 ± 3.9 ms, respectively; all ps > 0.05). The former tests illustrated that the T2* value could differentiate anatomic stages I and II (18.8 ± 4.8 ms and 26.9 ± 5.9 ms, respectively) or stages I and III (27.3 ± 3.6 ms). ROC analysis depicted the same cutoff T2* value of 21.3 ms for either differentiation. In addition, the Student's t test revealed that the T2* value could determine grouped T stages (T0 vs. T1-3: 17.0 ± 2.9 ms vs. 25.2 ± 6.2 ms; T0-1 vs. T2-3: 17.3 ± 3.0 ms vs. 27.1 ± 5.3 ms; and T0-2 vs. T3: 18.8 ± 4.2 ms vs. 27.8 ± 5.6 ms, all ps < 0.001). ROC analysis indicated that the T2* value could detect ESCCs (cutoff, 20 ms), and discriminate between stages T0-1 and T2-3 (cutoff, 21.3 ms) and between T0-2 and T3 (cutoff, 20.4 ms). CONCLUSION: The T2* value can be an additional quantitative indicator for detecting ESCC except for stage T1 cancer, and can preoperatively discriminate between some T stages and between anatomic stages of this tumor.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Neoplasias Esofágicas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Oxigênio/sangue , Idoso , Área Sob a Curva , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Curva ROC
19.
PLoS One ; 11(5): e0154545, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27171422

RESUMO

PURPOSE: To investigate whether liver lobe based T2* values measured on gradient recalled echo T2*-weighted imaging are associated with the presence and Child-Pugh class of hepatitis B-related cirrhosis. METHODS: Fifty-six patients with hepatitis B-related cirrhosis and 23 healthy control individuals were enrolled in this study and underwent upper abdominal T2*-weighted magnetic resonance imaging. T2* values of the left lateral lobe (LLL), left medial lobe (LML), right lobe (RL) and caudate lobe (CL) were measured on T2*-weighted imaging. Statistical analyses were performed to determine the association between liver lobe based T2* values and the presence and Child-Pugh class of cirrhosis. RESULTS: The T2* values of the LLL, LML and RL decreased with the progression of cirrhosis from Child-Pugh class A to C (r = -0.231, -0.223, and -0.395, respectively; all P < 0.05), except that of the CL (r = -0.181, P > 0.05). To a certain extent, Mann-Whitney U tests with Bonferroni correction for multigroup comparisons showed that the T2* values of the LLL, LML and RL could distinguish cirrhotic liver from healthy liver (all P < 0.05), whereas the T2* values of the CL could not (P > 0.05). Receiver operating characteristic analysis demonstrated that the T2* value of the RL could best distinguish cirrhosis from healthy liver, with an area under the receiver operating characteristic curve (AUC) of 0.713 among T2* values of the liver lobes, and that only the T2* value of the RL could distinguish Child-Pugh class C from A-B, with an AUC of 0.697 (all P < 0.05). CONCLUSION: The T2* value of the RL can be associated with the presence and Child-Pugh class of hepatitis B-related cirrhosis.


Assuntos
Hepatite B Crônica/complicações , Hepatite B Crônica/patologia , Cirrose Hepática/complicações , Cirrose Hepática/patologia , Fígado/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Curva ROC
20.
Nat Prod Res ; 30(1): 1-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26189919

RESUMO

A new labdane diterpene, (Z)-12,14-labdadien-15(16)-olide-17-oic acid (1), and a new natural cadinane sesquiterpene, 4-isopropyl-6-methyl-1-naphthalenemethanol (2), were isolated from the ethanolic extract of the rhizomes of Alpinia officinarum, together with three other products, galangin (3), kaempferol (4) and quercetin (5). Their structures were elucidated by using extensive spectroscopic methods. Compounds 1 and 2 showed no remarkable cytotoxic activity against HeLa and HepG2 cancer cell lines with IC50>50 µg mL(- 1).


Assuntos
Diterpenos/isolamento & purificação , Rizoma/química , Alpinia/química , Diterpenos/química , Diterpenos/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Flavonoides/isolamento & purificação , Células HeLa/efeitos dos fármacos , Células Hep G2/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Quempferóis/isolamento & purificação , Medicina Tradicional Chinesa , Estrutura Molecular , Naftalenos/química , Naftalenos/isolamento & purificação , Naftalenos/farmacologia , Extratos Vegetais/química , Quercetina/isolamento & purificação
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