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1.
Proc Natl Acad Sci U S A ; 119(51): e2211193119, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36520670

RESUMO

An interplay of geometrical frustration and strong quantum fluctuations in a spin-1/2 triangular-lattice antiferromagnet (TAF) can lead to exotic quantum states. Here, we report the neutron-scattering, magnetization, specific heat, and magnetocaloric studies of the recently discovered spin-1/2 TAF Na2BaCo(PO4)2, which can be described by a spin-1/2 easy axis XXZ model. The zero-field neutron diffraction experiment reveals an incommensurate antiferromagnetic ground state with a significantly reduced ordered moment of about 0.54(2) µB/Co. Different magnetic phase diagrams with magnetic fields in the ab plane and along the easy c-axis were extracted based on the magnetic susceptibility, specific heat, and elastic neutron-scattering results. In addition, two-dimensional (2D) spin dispersion in the triangular plane was observed in the high-field polarized state, and microscopic exchange parameters of the spin Hamiltonian have been determined through the linear spin wave theory. Consistently, quantum critical behaviors with the universality class of d = 2 and νz = 1 were established in the vicinity of the saturation field, where a Bose-Einstein condensation (BEC) of diluted magnons occurs. The newly discovered quantum criticality and fractional magnetization phase in this ideal spin-1/2 TAF present exciting opportunities for exploring exotic quantum phenomena.

2.
Anal Chem ; 96(2): 624-629, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38157203

RESUMO

Tumor metastasis and cancer recurrence are often a result of cell heterogeneity, where specific subpopulations of tumor cells may be resistant to radio- or chemotherapy. To investigate this physiological and phenotypic diversity, single-cell metabolomics provides a powerful approach at the chemical level, where distinct lipid profiles can be found in different tumor cells. Here, we established a highly sensitive platform using nanoflow liquid chromatography (nLC) combined with multinozzle emitter electrospray ionization mass spectrometry for more in-depth metabolomics profiling. Our platform identified 15 and 17 lipids from individual osteosarcoma (U2OS) and glioblastoma (GBM) cells when analyzing single-cell samples. Additionally, we used the functional single-cell selection (fSCS) pipeline to analyze the subpopulations of cells with a DNA damage response (DDR) in U2OS cells and fast migration in GBM cells. Specifically, we observed a down-regulation of polyunsaturated fatty acids (PUFAs) in U2OS cells undergoing DDR, such as fatty acids FA 20:3; O2 and FA 17:4; O3. Furthermore, ceramides (Cer 38:0; O3) and triglycerides (TG 36:0) were found to be down-regulated in fast-migrating GBM cells compared to the slow-migrating subpopulation. These findings suggest the potential roles of these metabolites and/or lipids in the cellular behavior of the subpopulations.


Assuntos
Glioblastoma , Espectrometria de Massas por Ionização por Electrospray , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Metabolômica/métodos , Ácidos Graxos Insaturados/metabolismo , Triglicerídeos
3.
Microb Ecol ; 86(2): 1189-1199, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36123554

RESUMO

Litter decomposition is the main source of soil organic carbon (SOC) pool, regarding as an important part of terrestrial ecosystem C dynamics. The turnover of SOC is mainly regulated by extracellular enzymes secreted by microorganisms. However, the response mechanism of soil C-degrading enzymes and SOC in litter decomposition remains unclear. To clarify how SOC fraction dynamics respond to C-degrading enzymes in litter decomposition, we used field experiments to collect leaf litter and SOC fractions from the underlying layer in Robinia pseudoacacia plantations on the Loess Plateau. Our results showed that SOC, easily oxidizable organic C, dissolved organic C, and microbial biomass C increased significantly during the decomposition process. Litter decomposition significantly decreased soil hydrolase activity, but slightly increased oxidase activity. Correlation analysis results showed that SOC fractions were significantly positively correlated with the litter mass, lignin, soil moisture, and oxidase activity, but significantly negatively correlated with cellulose content and soil pH. Partial least squares path models revealed that soil C-degrading enzymes can directly or indirectly affect the changes of soil C fractions. The most direct factors affecting the SOC fractions of topsoil during litter decomposition were litter lignin and cellulose degradation, soil pH, and C-degrading enzymes. Furthermore, regression analysis showed that the decrease of SOC stability in litter decomposition was closely related to the decrease of soil hydrolase to oxidase ratio. These results highlighted that litter degradation-induced changes in C-degrading enzyme activity significantly affected SOC fractions. Furthermore, the distribution of soil hydrolases and oxidases affected the stability of SOC during litter decomposition. These findings provided a theoretical framework for a more comprehensive understanding of C turnover and stabilization mechanisms between plant and soil.


Assuntos
Robinia , Solo , Solo/química , Ecossistema , Carbono/metabolismo , Lignina/metabolismo , Celulose/metabolismo , Hidrolases/metabolismo , Microbiologia do Solo , Oxirredutases , Florestas , China
4.
Int J Mol Sci ; 24(21)2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37958662

RESUMO

Chemotherapy using temozolomide is the standard treatment for patients with glioblastoma. Despite treatment, prognosis is still poor largely due to the emergence of temozolomide resistance. This resistance is closely linked to the widely recognized inter- and intra-tumoral heterogeneity in glioblastoma, although the underlying mechanisms are not yet fully understood. To induce temozolomide resistance, we subjected 21 patient-derived glioblastoma cell cultures to Temozolomide treatment for a period of up to 90 days. Prior to treatment, the cells' molecular characteristics were analyzed using bulk RNA sequencing. Additionally, we performed single-cell RNA sequencing on four of the cell cultures to track the evolution of temozolomide resistance. The induced temozolomide resistance was associated with two distinct phenotypic behaviors, classified as "adaptive" (ADA) or "non-adaptive" (N-ADA) to temozolomide. The ADA phenotype displayed neurodevelopmental and metabolic gene signatures, whereas the N-ADA phenotype expressed genes related to cell cycle regulation, DNA repair, and protein synthesis. Single-cell RNA sequencing revealed that in ADA cell cultures, one or more subpopulations emerged as dominant in the resistant samples, whereas N-ADA cell cultures remained relatively stable. The adaptability and heterogeneity of glioblastoma cells play pivotal roles in temozolomide treatment and contribute to the tumor's ability to survive. Depending on the tumor's adaptability potential, subpopulations with acquired resistance mechanisms may arise.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Dacarbazina/farmacologia , Dacarbazina/uso terapêutico , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Linhagem Celular Tumoral , Fenótipo , Genômica , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Regulação Neoplásica da Expressão Gênica
5.
Microb Ecol ; 83(1): 114-126, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33743015

RESUMO

Soil microorganisms play an important role in the circulation of materials and nutrients between plants and soil ecosystems, but the drivers of microbial community composition and diversity remain uncertain in different vegetation restoration patterns. We studied soil physicochemical properties (i.e., soil moisture, bulk density, pH, soil nutrients, available nutrients), plant characteristics (i.e., Shannon index [HPlant] and Richness index [SPlant], litter biomass [LB], and fine root biomass [FRB]), and microbial variables (biomass, enzyme activity, diversity, and composition of bacterial and fungal communities) in different plant succession patterns (Robinia pseudoacacia [MF], Caragana korshinskii [SF], and grassland [GL]) on the Loess Plateau. The herb communities, soil microbial biomass, and enzyme activities were strongly affected by vegetation restoration, and soil bacterial and fungal communities were significantly different from each other at the sites. Correlation analysis showed that LB and FRB were significantly positively correlated with the Chao index of soil bacteria, soil microbial biomass, enzyme activities, Proteobacteria, Zygomycota, and Cercozoa, while negatively correlated with Actinobacteria and Basidiomycota. In addition, soil water content (SW), pH, and nutrients have important effects on the bacterial and fungal diversities, as well as Acidobacteria, Proteobacteria, Actinobacteria, Nitrospirae, Zygomycota, and microbial biomass. Furthermore, plant characteristics and soil properties modulated the composition and diversity of soil microorganisms, respectively. Overall, the relative contribution of vegetation and soil to the diversity and composition of soil bacterial and fungal communities illustrated that plant characteristics and soil properties may synergistically modulate soil microbial communities, and the composition and diversity of soil bacterial and fungal communities mainly depend on plant biomass and soil nutrients.


Assuntos
Microbiota , Solo , Biomassa , China , Nutrientes , Solo/química , Microbiologia do Solo
6.
Rheumatology (Oxford) ; 60(4): 1734-1746, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33068407

RESUMO

OBJECTIVE: The long non-coding RNA plays an important role in inflammation and autoimmune diseases. The aim of this study is to screen and identify abnormally expressed lncRNAs in peripheral blood neutrophils of SLE patients as novel biomarkers and to explore the relationship between lncRNAs levels and clinical features, disease activity and organ damage. METHODS: RNA-seq technology was used to screen differentially expressed lncRNAs in neutrophils from SLE patients and healthy donors. Based on the results of screening, candidate lncRNA levels in neutrophils of 88 SLE patients, 35 other connective disease controls, and 78 healthy controls were qualified by real-time quantitative polymerase chain reaction. RESULTS: LncRNA expression profiling revealed 360 up-regulated lncRNAs and 224 down-regulated lncRNAs in neutrophils of SLE patients when compared with healthy controls. qPCR assay validated that the expression of Lnc-FOSB-1:1 was significantly decreased in neutrophils of SLE patients when compared with other CTD patients or healthy controls. It correlated negatively with SLE Disease Activity Index 2000 (SLEDAI-2K) score (r = -0.541, P < 0.001) and IFN scores (r = -0.337, P = 0.001). More importantly, decreased Lnc-FOSB-1:1 expression was associated with lupus nephritis. Lower baseline Lnc-FOSB-1:1 level was associated with higher risk of future renal involvement (within an average of 2.6 years) in patients without renal disease at baseline (P = 0.019). CONCLUSION: LncRNA expression profile in neutrophils of SLE patients revealed differentially expressed lncRNAs. Validation study on Lnc-FOSB-1:1 suggest that it is a potential biomarker for prediction of near future renal involvement.


Assuntos
Lúpus Eritematoso Sistêmico/genética , Nefrite Lúpica/genética , Neutrófilos/metabolismo , RNA Longo não Codificante/metabolismo , Adolescente , Adulto , Idoso , Biomarcadores/metabolismo , Estudos de Casos e Controles , Regulação para Baixo , Perfilação da Expressão Gênica , Humanos , Lúpus Eritematoso Sistêmico/complicações , Nefrite Lúpica/metabolismo , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima , Adulto Jovem
7.
J Am Chem Soc ; 142(41): 17662-17669, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32900188

RESUMO

Solid-state topochemical polymerization (SSTP) is a promising method to construct functional crystalline polymeric materials, but in contrast to various reactions that happen in solution, only very limited types of SSTP reactions are reported. Diels-Alder (DA) and dehydro-DA (DDA) reactions are textbook reactions for preparing six-membered rings in solution but are scarcely seen in solid-state synthesis. Here, using multiple cutting-edge techniques, we demonstrate that the solid 1,4-diphenylbutadiyne (DPB) undergoes a DDA reaction under 10-20 GPa with the phenyl as the dienophile. The crystal structure at the critical pressure shows that this reaction is "distance-selected". The distance of 3.2 Å between the phenyl and the phenylethynyl facilitates the DDA reaction, while the distances for other DDA and 1,4-addition reactions are too large to allow the bonding. The obtained products are crystalline armchair graphitic nanoribbons, and hence our studies open a new route to construct the crystalline carbon materials with atomic-scale control.

8.
BMC Public Health ; 18(1): 489, 2018 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-29650008

RESUMO

BACKGROUND: Local malaria transmission has decreased rapidly since the National Malaria Elimination Action Plan was launched in China in 2010. However, imported malaria cases from Africa and Southeast Asia still occur in China due to overseas laborers. Diagnosis by microscopy is the gold standard for malaria and is used in most hospitals in China. However, the current capacity of microscopists to manage malaria cases in hospitals and public health facilities to meet the surveillance needs to eliminate and prevent the reintroduction of malaria is unknown. METHODS: Malaria diagnoses were assessed by comparing the percentage of first visit and confirmed malaria diagnoses at Centers for Disease Control and Prevention (CDCs) and hospitals. The basic personnel information for public health departments and hospitals at different levels was investigated. The skills of microscopists for blood smear preparation and slide interpretation were also examined at the county and township levels. RESULTS: Inaccurate rate with 13.49% and 7.32%, respectively, in 2013 and 2014, from 341 and 355 reported cases from sub-provincial levels in Jiangsu province. Most of the 523 malaria cases reported in Nantong Prefecture from 2000 to 2014 involved patients who first visited county CDCs seeking treatment, however, none of these cases received confirmed diagnosis of malaria in townships or villages.The staff at county CDCs and hospitals with a higher education background performed better at making and interpreting blood smears than staff from townships. CONCLUSIONS: The network for malaria elimination in an entire province has been well established. However, an insufficient capacity for malaria diagnosis was observed, especially the preparing and reading the blood smears at the township and village levels, which is a challenge to achieving and maintaining malaria elimination.


Assuntos
Erradicação de Doenças , Pessoal de Laboratório/provisão & distribuição , Malária/prevenção & controle , Microscopia , China/epidemiologia , Humanos , Malária/epidemiologia
9.
J Am Chem Soc ; 139(12): 4574-4581, 2017 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-28240901

RESUMO

Perovskite PbCoO3 synthesized at 12 GPa was found to have an unusual charge distribution of Pb2+Pb4+3Co2+2Co3+2O12 with charge orderings in both the A and B sites of perovskite ABO3. Comprehensive studies using density functional theory (DFT) calculation, electron diffraction (ED), synchrotron X-ray diffraction (SXRD), neutron powder diffraction (NPD), hard X-ray photoemission spectroscopy (HAXPES), soft X-ray absorption spectroscopy (XAS), and measurements of specific heat as well as magnetic and electrical properties provide evidence of lead ion and cobalt ion charge ordering leading to Pb2+Pb4+3Co2+2Co3+2O12 quadruple perovskite structure. It is shown that the average valence distribution of Pb3.5+Co2.5+O3 between Pb3+Cr3+O3 and Pb4+Ni2+O3 can be stabilized by tuning the energy levels of Pb 6s and transition metal 3d orbitals.

10.
Eur J Clin Pharmacol ; 72(6): 689-95, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27023460

RESUMO

OBJECTIVE: Zuojin Pill has been shown to inhibit the cytochrome P450 (CYP) 2D6 isoenzyme in vitro. In Chinese individuals, CYP 2D6*10 is the most common allele with reduced enzyme activity. In this study, we investigated the pharmacokinetic interaction between Zuojin Pill and the sensitive CYP2D6 probe dextromethorphan in healthy Chinese volunteers with CYP2D6*10 genotype. METHODS: A pharmacokinetics interaction study was carried out in three groups with CYP2D6*1/*1 (n = 6), CYP2D6*1/*10 (n = 6), and CYP2D6*10/*10 (n = 6) genotypes. Each participant received a single oral dose of dextromethorphan (15 mg) followed by Zuojin Pill (3 g twice daily) for 7 days, and received 3 g Zuojin Pill with 15 mg dextromethorphan in the last day. Blood samples (0-24 h) and urine samples (0-12 h) were collected at baseline and after the administration of Zuojin Pill, and the samples' concentration of dextromethorphan and its main metabolite dextrorphan was determined. RESULTS: Compared to baseline values, co-administration of Zuojin Pill (3 g twice daily) for 7 days increased the AUC0-24 of dextromethorphan [mean (90 % CI)] by 3.00-fold (2.49∼3.61) and 1.71-fold (1.42∼2.06), and decreased oral clearance(CL/F) by 0.27-fold (0.2-0.40) and 0.57-fold (0.48-0.67) in the participants with CYP2D6*1/*1 and CYP2D6*1/*10 genotypes, respectively. In contrast, no significant change was observed in these pharmacokinetic parameters of the participants with CYP2D6*10/*10 genotype. CONCLUSION: These data demonstrated that administration of Zuojin Pill inhibited moderately CYP2D6-mediated metabolism of dextromethorphan in healthy volunteers. The inhibitory influence of CYP2D6 was greater in CYP2D6*1/*1 and CYP2D6*1/*10 groups than CYP2D6 *10/*10 group.


Assuntos
Antitussígenos/farmacocinética , Citocromo P-450 CYP2D6/genética , Dextrometorfano/farmacocinética , Medicamentos de Ervas Chinesas/farmacologia , Interações Ervas-Drogas , Adulto , Antitussígenos/sangue , Antitussígenos/urina , Povo Asiático/genética , Dextrometorfano/sangue , Dextrometorfano/urina , Feminino , Genótipo , Voluntários Saudáveis , Humanos , Masculino , Adulto Jovem
11.
Inorg Chem ; 54(8): 3896-904, 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25833295

RESUMO

K2NiF4-type LaSrAlO4 and Sr2TiO4 exhibit anisotropic and isotropic thermal expansion, respectively; however, their structural origin is unknown. To address this unresolved issue, the crystal structure and thermal expansion of LaSrAlO4 and Sr2TiO4 have been investigated through high-temperature neutron and synchrotron X-ray powder diffraction experiments and ab initio electronic calculations. The thermal expansion coefficient (TEC) along the c-axis (αc) being higher than that along the a-axis (αa) of LaSrAlO4 [αc = 1.882(4)αa] is mainly ascribed to the TEC of the interatomic distance between Al and apical oxygen O2 α(Al-O2) being higher than that between Al and equatorial oxygen O1 α(Al-O1) [α(Al-O2) = 2.41(18)α(Al-O1)]. The higher α(Al-O2) is attributed to the Al-O2 bond being longer and weaker than the Al-O1 bond. Thus, the minimum electron density and bond valence of the Al-O2 bond are lower than those of the Al-O1 bond. For Sr2TiO4, the Ti-O2 interatomic distance, d(Ti-O2), is equal to that of Ti-O1, d(Ti-O1) [d(Ti-O2) = 1.0194(15)d(Ti-O1)], relative to LaSrAlO4 [d(Al-O2) = 1.0932(9)d(Al-O1)]. Therefore, the bond valence and minimum electron density of the Ti-O2 bond are nearly equal to those of the Ti-O1 bond, leading to isotropic thermal expansion of Sr2TiO4 than LaSrAlO4. These results indicate that the anisotropic thermal expansion of K2NiF4-type oxides, A2BO4, is strongly influenced by the anisotropy of B-O chemical bonds. The present study suggests that due to the higher ratio of interatomic distance d(B-O2)/d(B-O1) of A2(2.5+)B(3+)O4 compared with A2(2+)B(4+)O4, A2(2.5+)B(3+)O4 compounds have higher α(B-O2), and A2(2+)B(4+)O4 materials exhibit smaller α(B-O2), leading to the anisotropic thermal expansion of A2(2.5+)B(3+)O4 and isotropic thermal expansion of A2(2+)B(4+)O4. The "true" thermal expansion without the chemical expansion of A2BO4 is higher than that of ABO3 with a similar composition.

12.
BMC Musculoskelet Disord ; 16: 289, 2015 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-26459411

RESUMO

BACKGROUND: The purpose was to investigate the effect of double-leg semisquat with hip adduction on the activation of vastus medialis oblique (VMO) and vastus lateralis (VL) in patients with patellofemoral pain syndrome (PFPS). METHODS: Thirty patients with PFPS were designated to the study group, while 30 healthy matched subjects were enrolled in the control group. The activation of VL and VMO was recorded with surface electromyography (EMG) during double-leg semisquat (DS) and double-leg semisquat with hip adduction (DS-HA). The time domain and frequency domain indexes of the electromyography data were collected for analysis. RESULTS: In the study group, the time domain indexes (RMS, IEMG) and frequency domain index (MPF) of VL were significant higher than VMO in the test of DS (P < 0.05); and the time domain of VMO was significantly higher in the test of DS-HA when compared to DS (P < 0.05) while there was no difference in the activation of VL. CONCLUSIONS: In the study group, an increase in activity of the VMO was observed through the surface EMG signal in the double-leg semisquat exercise with hip adduction compared to the exercise without hip adduction. This finding indicates that VMO activation can be more selectively obtained through the exercise with hip adduction which can help balance the VL and VMO.


Assuntos
Síndrome da Dor Patelofemoral/fisiopatologia , Músculo Quadríceps/fisiopatologia , Adulto , Estudos de Casos e Controles , Eletromiografia , Feminino , Humanos , Masculino , Adulto Jovem
13.
Artigo em Zh | MEDLINE | ID: mdl-26931048

RESUMO

From 1999 to 2014 a total of 23 cases of malaria were reported in Rudong County, Jiangsu Province, comprising one indigenous case of vivax malaria, 9 imported cases of vivax malaria, and 13 imported cases of falciparum malaria. The imported cases accounted for 95.7%(22/23) of all cases. The first diagnosis was mainly made in town hospitals and village clinics, accounting for 60.9%. There was no obvious seasonal variation in disease onset, and all cases reported in 2004 were imported.


Assuntos
Epidemias , Malária/epidemiologia , China/epidemiologia , Humanos , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Estações do Ano
14.
J Biol Chem ; 288(49): 35406-16, 2013 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-24142698

RESUMO

Pyruvate kinase M2 (PKM2) is a key player in the Warburg effect of cancer cells. However, the mechanisms of regulating PKM2 are not fully elucidated. Here, we identified the protein-serine/threonine kinase PIM2, a known oncogene, as a novel binding partner of PKM2. The interaction between PIM2 and PKM2 was confirmed by multiple biochemical approaches in vitro and in cultured cells. Importantly, we found that PIM2 could directly phosphorylate PKM2 on the Thr-454 residue, resulting in an increase of PKM2 protein levels. Compared with wild type, PKM2 with the phosphorylation-defective mutation displayed a reduced effect on glycolysis, co-activating HIF-1α and ß-catenin, and cell proliferation, while enhancing mitochondrial respiration of cancer cells. These findings demonstrate that PIM2-dependent phosphorylation of PKM2 is critical for regulating the Warburg effect in cancer, highlighting PIM2 as a potential therapeutic target.


Assuntos
Neoplasias/genética , Neoplasias/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Piruvato Quinase/metabolismo , Integração Viral/genética , Linhagem Celular Tumoral , Glicólise , Células HEK293 , Células Hep G2 , Humanos , Oncogenes , Fosforilação , Ligação Proteica , Piruvato Quinase/química , Piruvato Quinase/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Treonina/química , Técnicas do Sistema de Duplo-Híbrido
15.
J Am Chem Soc ; 136(4): 1162-5, 2014 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-24422495

RESUMO

In this paper we present in situ transmission electron microscopy of synthetic polymeric nanoparticles with emphasis on capturing motion in a solvated, aqueous state. The nanoparticles studied were obtained from the direct polymerization of a Pt(II)-containing monomer. The resulting structures provided sufficient contrast for facile imaging in situ. We contend that this technique will quickly become essential in the characterization of analogous systems, especially where dynamics are of interest in the solvated state. We describe the preparation of the synthetic micellar nanoparticles together with their characterization and motion in liquid water with comparison to conventional electron microscopy analyses.


Assuntos
Nanopartículas/química , Polímeros/química , Termodinâmica , Água/química , Microscopia Eletrônica de Transmissão , Modelos Moleculares , Estrutura Molecular , Tamanho da Partícula , Polímeros/síntese química , Propriedades de Superfície
16.
J Transl Med ; 12: 330, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25491303

RESUMO

BACKGROUND: Although a variety of drugs have been used to treat the symptoms of rheumatoid arthritis (RA), none of them are able to cure the disease. Interferon ß (IFN-ß) has pleiotropic effects on RA, but whether it can be used to treat RA remains globally controversial. Thus, in this study we tested the effects of IFN-ß on RA patients and on collagen antibody-induced arthritis (CAIA) model mice. METHODS: The cytokine and auto-antibody expression profiles in the serum and synovial fluid (SF) from RA patients were assessed using enzyme-linked immunosorbent assay (ELISA) and compared with the results from osteoarthritis (OA) patients. Exogenous IFN-ß was administered to RA patients and CAIA model mice, and the therapeutic effects were evaluated. Endogenous IFN-ß expression in the joint bones of CAIA model mice was evaluated by quantitative real-time PCR (qRT-PCR). The effects of exogenous IFN-ß on CAIA model mice were assessed using a clinical scoring system, hematoxylin eosin and safranin-O with fast green counterstain histology, molybdenum target X-ray, and tartrate-resistant acid phosphatase (TRAP) staining. The RANKL-RANK signaling pathway was analyzed using qRT-PCR. The RAW 264.7 cell line was differentiated into osteoclasts with RANKL stimulation and then treated with exogenous IFN-ß. RESULTS: The expression of inflammatory cytokines (IFN-γ, IL-17, MMP-3, and RANKL) and auto-antibodies (CII antibodies, RF-IgM, and anti-CCP/GPI) were significantly higher in RA compared with OA patients. After IFN-ß intervention, some clinical symptoms in RA patients were partially alleviated, and the expression of IFN-γ, IL-17, MMP-3, and OPG) returned to normal levels. In the CAIA model, the expression of endogenous IFN-ß in the joint bones was decreased. After IFN-ß administration, the arthritis scores were decreased; synovial inflammation, cartilage, and bone destruction were clearly attenuated; and the expression of c-Fos and NFATc1 were reduced, while RANKL and TRAF6 expression was unchanged. In addition, exogenous IFN-ß directly inhibited RANKL-induced osteoclastogenesis. CONCLUSIONS: Exogenous IFN-ß administration immunomodulates CAIA, may reduce joint inflammation and, perhaps more importantly, bone destruction by inhibiting the RANKL-c-Fos signaling pathway. Exogenous IFN-ß intervention should be selectively used on RA patients because it may only be useful for RA patients with low endogenous IFN-ß expression.


Assuntos
Artrite Experimental/metabolismo , Autoanticorpos/imunologia , Colágeno/imunologia , Interferon beta/farmacologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ligante RANK/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Artrite Experimental/imunologia , Ensaio de Imunoadsorção Enzimática , Camundongos , Camundongos Endogâmicos BALB C
17.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(11): 1386-9, 2014 Nov.
Artigo em Zh | MEDLINE | ID: mdl-25566635

RESUMO

By reviewing research contents of patient-reported outcome (PRO) and discussing Chinese medicine (CM) theories related to chronic liver disease (CLD), we have followed international PRO questionnaire development specification, combined CM theories such as uniformed spirit and body, correspondence between human and the universe, yin in property and yang in function of Gan, and seven emotions, and constructed theoretical structure of PRO questionnaire of treating CLD, including four major areas as physiology, psychology, independence, and society and nature. Of them, the physiological field contained six aspects such as blood deficiency, yin deficiency, bleeding, disorder of qi movement, improper transformation and transportation of Pi-Wei, and abnormal biliary excretion. The psychological field contained two aspects: Gan-related emotions and general disease related emotions. The independence field contained two aspects: daily life and study and work. The field of society and nature contains three aspects: social relations, social environment, and natural adaptability.


Assuntos
Hepatopatias/terapia , Medicina Tradicional Chinesa , Inquéritos e Questionários , Humanos , Deficiência da Energia Yang , Deficiência da Energia Yin
18.
Heliyon ; 10(7): e28637, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38571627

RESUMO

Chinese medicinal materials (CMMs) are important strategic resource in China. The cultivation process of medicinal plants is the key link which directly affect the quality and efficacy. The literatures of CMMs cultivation were acquired from China National Knowledge Infrastructure (CNKI) database and State Intellectual Property Office (SIPO) patent database for the years between 2001 and 2021. All the articles found were subjected to bibliometric analysis. The development trends and key topics were analyzed and visualized by VOSviewer and CiteSpace software. The results indicate that ecological planting, under-forest economy, intercropping patterns and industrialization production are the research hotspots in this field; cultivation technology and nutritional fertilization technology are the main areas addressed in recent years. Therefore, the high-quality and sustainable development of CMMs cultivation should be examined in terms of theoretical approaches, technical innovation, multi-cooperation, and intellectual property protection.

19.
J Am Chem Soc ; 135(50): 18710-3, 2013 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-24308273

RESUMO

Matrix metalloproteinase enzymes, overexpressed in HT-1080 human fibrocarcinoma tumors, were used to guide the accumulation and retention of an enzyme-responsive nanoparticle in a xenograft mouse model. The nanoparticles were prepared as micelles from amphiphilic block copolymers bearing a simple hydrophobic block and a hydrophilic peptide brush. The polymers were end-labeled with Alexa Fluor 647 dyes leading to the formation of labeled micelles upon dialysis of the polymers from DMSO/DMF to aqueous buffer. This dye-labeling strategy allowed the presence of the retained material to be visualized via whole animal imaging in vivo and in ex vivo organ analysis following intratumoral injection into HT-1080 xenograft tumors. We propose that the material is retained by virtue of an enzyme-induced accumulation process whereby particles change morphology from 20 nm spherical micelles to micrometer-scale aggregates, kinetically trapping them within the tumor. This hypothesis is tested here via an unprecedented super-resolution fluorescence analysis of ex vivo tissue slices confirming a particle size increase occurs concomitantly with extended retention of responsive particles compared to unresponsive controls.


Assuntos
Enzimas/química , Microscopia de Fluorescência/métodos , Nanopartículas , Neoplasias/metabolismo , Animais , Linhagem Celular , Xenoenxertos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Camundongos
20.
IUBMB Life ; 65(11): 904-10, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24265197

RESUMO

One of the principal biochemical characteristics of malignant cells compared to normal cells is a metabolic switch from oxidative phosphorylation to increased glycolysis, even under hypoxic conditions, and is termed the Warburg effect. Lactate dehydrogenase A (LDHA) catalyzes the conversion of pyruvate to lactate and is considered to be a key checkpoint of anaerobic glycolysis. It is elevated in many types of cancers and has been linked to tumor growth, maintenance, and invasion; therefore, its inhibition may restrict the energy supply in tumors and thereby reduce the metastatic and invasive potential of cancer cells. This enzyme is receiving a great deal of attention as a potential diagnostic marker or a predictive biomarker for many types of cancer and as a therapeutic target for new anticancer treatments. In this review, we summarize the role of LDHA in cancer, discuss its potential significance in clinical diagnosis and prognosis of cancer, and propose LDHA as a novel target for the inhibition of tumor growth and invasiveness.


Assuntos
Glicólise/fisiologia , L-Lactato Desidrogenase/fisiologia , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Animais , Biomarcadores Tumorais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Metabolismo Energético , Humanos , Isoenzimas/sangue , Isoenzimas/fisiologia , L-Lactato Desidrogenase/sangue , Lactato Desidrogenase 5 , Camundongos , Neoplasias/fisiopatologia , Fosforilação Oxidativa , Prognóstico , Ácido Pirúvico/metabolismo
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