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1.
Brain ; 144(9): 2784-2797, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34259858

RESUMO

Tau protein neurofibrillary tangles are closely linked to neuronal/synaptic loss and cognitive decline in Alzheimer's disease and related dementias. Our knowledge of the pattern of neurofibrillary tangle progression in the human brain, critical to the development of imaging biomarkers and interpretation of in vivo imaging studies in Alzheimer's disease, is based on conventional two-dimensional histology studies that only sample the brain sparsely. To address this limitation, ex vivo MRI and dense serial histological imaging in 18 human medial temporal lobe specimens (age 75.3 ± 11.4 years, range 45 to 93) were used to construct three-dimensional quantitative maps of neurofibrillary tangle burden in the medial temporal lobe at individual and group levels. Group-level maps were obtained in the space of an in vivo brain template, and neurofibrillary tangles were measured in specific anatomical regions defined in this template. Three-dimensional maps of neurofibrillary tangle burden revealed significant variation along the anterior-posterior axis. While early neurofibrillary tangle pathology is thought to be confined to the transentorhinal region, we found similar levels of burden in this region and other medial temporal lobe subregions, including amygdala, temporopolar cortex, and subiculum/cornu ammonis 1 hippocampal subfields. Overall, the three-dimensional maps of neurofibrillary tangle burden presented here provide more complete information about the distribution of this neurodegenerative pathology in the region of the cortex where it first emerges in Alzheimer's disease, and may help inform the field about the patterns of pathology spread, as well as support development and validation of neuroimaging biomarkers.


Assuntos
Mapeamento Encefálico/métodos , Imageamento Tridimensional/métodos , Emaranhados Neurofibrilares/patologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/patologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
2.
Mycoses ; 64(8): 841-850, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34051012

RESUMO

BACKGROUND: Invasive candidiasis is a growing concern worldwide, especially in immunocompromised patients, including ICU patients. OBJECTIVES: As Candida albicans is the leading cause of candidaemia, it is important to investigate the evolution of C. albicans in patients with candidaemia. METHODS: We analysed 238 strains of C. albicans isolated from different body sites. Antifungal susceptibility testing, CAI loci genotyping and multilocus sequence typing (MLST) of all isolates were performed. The relationships among the total isolates that differed in sequence at only one of the seven housekeeping gene loci were analysed using eBURST. RESULTS: Multilocus sequence typing analysis in 238 isolates by combining seven housekeeping alleles revealed 175 diploid sequence types, in which 84 were newly identified. eBURST analysis for these data recognised 19 clonal complexes (CCs) and 79 singletons. Besides, seventy-three CAI genotypes were identified. Blood isolates showed maximum genotypes (49), and the dominant genotypes were CAI 17-21 and CAI 21-21. Oral isolates possessed 25 CAI genotypes, and the dominant genotypes were CAI 17-21 and CAI 21-21 as well. Since isolates with CAI allele numbers <30 showed easier transmission, CAI 17-21 and CAI 21-21 were the most frequently transmitted. Finally, the CAI genotypes were classified into six groups. CONCLUSIONS: This work revealed the oral and blood strains isolated from the patients with candidaemia in ICU shared the identical dominant CAI genotypes. Our data expanded the C. albicans MLST database and helped with understanding the evolution and spread of invasive candidiasis.


Assuntos
Candida albicans/genética , Candida albicans/isolamento & purificação , Candidíase Invasiva/etiologia , Candidíase Invasiva/microbiologia , Técnicas de Genotipagem/métodos , Antifúngicos/farmacologia , Candida albicans/classificação , Candida albicans/efeitos dos fármacos , Candidíase Invasiva/sangue , China , Genótipo , Humanos , Boca/microbiologia , Tipagem de Sequências Multilocus/métodos , Técnicas de Tipagem Micológica , Filogenia
3.
Proc Natl Acad Sci U S A ; 115(16): 4252-4257, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29592955

RESUMO

Although the hippocampus is one of the most studied structures in the human brain, limited quantitative data exist on its 3D organization, anatomical variability, and effects of disease on its subregions. Histological studies provide restricted reference information due to their 2D nature. In this paper, high-resolution (∼200 × 200 × 200 µm3) ex vivo MRI scans of 31 human hippocampal specimens are combined using a groupwise diffeomorphic registration approach into a 3D probabilistic atlas that captures average anatomy and anatomic variability of hippocampal subfields. Serial histological imaging in 9 of the 31 specimens was used to label hippocampal subfields in the atlas based on cytoarchitecture. Specimens were obtained from autopsies in patients with a clinical diagnosis of Alzheimer's disease (AD; 9 subjects, 13 hemispheres), of other dementia (nine subjects, nine hemispheres), and in subjects without dementia (seven subjects, nine hemispheres), and morphometric analysis was performed in atlas space to measure effects of age and AD on hippocampal subfields. Disproportional involvement of the cornu ammonis (CA) 1 subfield and stratum radiatum lacunosum moleculare was found in AD, with lesser involvement of the dentate gyrus and CA2/3 subfields. An association with age was found for the dentate gyrus and, to a lesser extent, for CA1. Three-dimensional patterns of variability and disease and aging effects discovered via the ex vivo hippocampus atlas provide information highly relevant to the active field of in vivo hippocampal subfield imaging.


Assuntos
Envelhecimento/patologia , Doença de Alzheimer/patologia , Atlas como Assunto , Hipocampo/patologia , Imageamento por Ressonância Magnética , Neuroimagem , Idoso , Atrofia , Giro Denteado/patologia , Humanos , Imageamento Tridimensional , Tamanho do Órgão
4.
J Toxicol Pathol ; 34(1): 73-82, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33627946

RESUMO

Autophagy is a lysosomal-dependent degradation pathway in eukaryotic cells. Recent studies have reported that autophagy can facilitate the activation of hepatic stellate cells (HSCs) and fibrogenesis of the liver during long-term carbon tetrachloride (CCl4) exposure. However, little is known about the role of autophagy in CCl4-induced acute hepatic failure (AHF). This study aimed to identify whether modulation of autophagy can affect CCl4-induced AHF and evaluate the upstream signaling pathways mediated by CCl4-induced autophagy in rats. The accumulation of specific punctate distribution of endogenous LC3-II, increased expression of LC3-II, Atg5, and Atg7 genes/proteins, and decreased expression of p62 gene were observed after acute liver injury was induced by CCl4 in rats, indicating that CCl4 resulted in a high level of autophagy. Moreover, loss of autophagic function by using chloroquine (CQ, an autophagic inhibitor) aggravated liver function, leading to increased expression of p21 (a cyclin-dependent kinase inhibitor) in CCl4-treated rats. Furthermore, the AMPK-mTORC1-ULK1 axis was found to serve a function in CCl4-induced autophagy. These results reveal that AMPK-mTORC1-ULK1 signaling-induced autophagy has a protective role in CCl4-induced hepatotoxicity by inhibiting the p21 pathway. This study suggests a useful strategy aimed at ameliorating CCl4-induced acute hepatotoxicity by autophagy.

5.
Hippocampus ; 30(6): 545-564, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31675165

RESUMO

Hippocampal subfield segmentation on in vivo MRI is of great interest for cognition, aging, and disease research. Extant subfield segmentation protocols have been based on neuroanatomical references, but these references often give limited information on anatomical variability. Moreover, there is generally a mismatch between the orientation of the histological sections and the often anisotropic coronal sections on in vivo MRI. To address these issues, we provide a detailed description of hippocampal anatomy using a postmortem dataset containing nine specimens of subjects with and without dementia, which underwent a 9.4 T MRI and histological processing. Postmortem MRI matched the typical orientation of in vivo images and segmentations were generated in MRI space, based on the registered annotated histological sections. We focus on the following topics: the order of appearance of subfields, the location of subfields relative to macroanatomical features, the location of subfields in the uncus and tail and the composition of the dark band, a hypointense layer visible in T2-weighted MRI. Our main findings are that: (a) there is a consistent order of appearance of subfields in the hippocampal head, (b) the composition of subfields is not consistent in the anterior uncus, but more consistent in the posterior uncus, (c) the dark band consists only of the CA-stratum lacunosum moleculare, not the strata moleculare of the dentate gyrus, (d) the subiculum/CA1 border is located at the middle of the width of the hippocampus in the body in coronal plane, but moves in a medial direction from anterior to posterior, and (e) the variable location and composition of subfields in the hippocampal tail can be brought back to a body-like appearance when reslicing the MRI scan following the curvature of the tail. Our findings and this publicly available dataset will hopefully improve anatomical accuracy of future hippocampal subfield segmentation protocols.


Assuntos
Bases de Dados Factuais/tendências , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Imageamento por Ressonância Magnética/tendências , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Ecotoxicol Environ Saf ; 171: 728-736, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30658309

RESUMO

Quantum dots (QDs), as a kind of novel nanomaterial, have the extensive applications in various fields, inevitably leading to increasing risks for the ecological environment. The mobilization of cadmium including metal smelting and subsequent machining for multifarious applications has caused the release of cadmium element into the environment. In this study, we evaluated the potential toxicity of a novel nanoparticle material CdSe QDs, using two green algae Chlorella pyrenoidosa and Scenedesmus obliquus. The impact of CdSe QDs and cadmium ions on algae and the sensitivity of the two algae on target compounds were also considered and compared. Our results showed the algal growth rates and chlorophyll content decreased with increasing exposure concentrations and durations. Moreover, the glutathione levels were decreased while the activities of superoxide dismutase increased, exhibiting their pivotal functions in defeating toxic stress. The increment of malondialdehyde levels revealed that the stresses of CdSe QDs and cadmium ions were contributed to the occurrence of oxidative damage. Our study also indicated that the impact of CdSe QDs was stronger than that of cadmium nitrate and the algal response was also species-specific. In addition, the TEM photographs of the algal ultrastructure showed the presence of surface attachment and uptake of QDs.


Assuntos
Compostos de Cádmio/toxicidade , Chlorella/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Pontos Quânticos/toxicidade , Scenedesmus/efeitos dos fármacos , Compostos de Selênio/toxicidade , Chlorella/crescimento & desenvolvimento , Chlorella/metabolismo , Clorofila/metabolismo , Relação Dose-Resposta a Droga , Malondialdeído/metabolismo , Metalurgia , Scenedesmus/crescimento & desenvolvimento , Scenedesmus/metabolismo , Superóxido Dismutase/metabolismo
7.
Cell Physiol Biochem ; 45(6): 2540-2547, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29558758

RESUMO

BACKGROUND/AIMS: B and T lymphocyte attenuator (BTLA) is an immune inhibitory receptor involved in the pathogenesis of chronic viral infections. Little is known about the effects of BTLA gene polymorphisms on chronic hepatitis B virus (HBV) infections. In this study, we investigated whether the polymorphisms of BTLA are associated with the progression of chronic HBV infection. METHODS: A total of 382 chronic HBV carriers and 170 healthy individuals in the same region were recruited for this study. The chronic HBV carriers were divided into three groups: asymptomatic HBV carriers (ASC), moderate chronic hepatitis B group (MCHB), and severe chronic hepatitis B group (SCHB). Two BTLA functional single nucleotide polymorphisms (SNPs; rs76844316 and rs9288952) were genotyped by polymerase chain reaction and sequenced directly. RESULTS: The results showed that the frequency of the G allele of rs76844316 was significantly lower in the SCHB group than in the other three groups. Subjects bearing at least one G allele (TG or GG genotype) at rs76844316 had decreased susceptibility to severe chronic hepatitis B compared with those bearing the TT genotype. Haplotype analysis of the two SNPs revealed that the frequency of the G-G haplotype was significantly lower in SCHB patients than in controls. Moreover, in the SCHB group, patients carrying the G allele of rs76844316 tended to have lower ALT levels than those without it. CONCLUSION: Our findings suggest that the genetic variants of rs76844316 in BTLA influence the susceptibility to severe chronic hepatitis B and might play a protective role against the progression of chronic hepatitis B.


Assuntos
Hepatite B Crônica/genética , Polimorfismo de Nucleotídeo Único , Receptores Imunológicos/genética , Adulto , Feminino , Predisposição Genética para Doença , Genótipo , Haplótipos , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/patologia , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade
8.
Cell Physiol Biochem ; 46(2): 461-470, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29614505

RESUMO

BACKGROUND/AIMS: Patients with hepatitis B virus (HBV) infection are at a high risk of developing hepatocellular carcinoma (HCC). In this study, we aim to investigate the roles of HBV on angiogenin (ANG), as well as the effects on cell proliferation in presence of ANG down-regulation. METHODS: Serum ANG was determined by ELISA. The expression of ANG mRNA and protein in HCC cell lines with or without HBV/HBx were determined. Western blot and ELISA were conducted to determine the effects of HBV/HBx on IL-6 expression. The role of IL-6 on ANG was evaluated by IL-6 recombinant protein or IL-6 neutralizing antibody. Immunofluorescence staining was used to detect the nuclear translocation of ANG. MTT was performed to evaluate the relative inhibition ratio. RESULT: In vivo experiments showed elevation of serum ANG in patients infected with HBV. In vitro experiments showed HBV and HBx contributed to the transcription and translation of ANG. ANG expression showed increase after IL-6 stimulation, and ANG protein decreased in the presence of IL-6 blocking with its antibody. HBV promoted nuclear translocation of ANG. Inhibiting ANG expression or blocking of nuclear transfer of ANG attenuated the 45S rRNA synthesis and cell proliferation. CONCLUSION: HBV and HBx protein can increase the level of ANG through IL-6. HBV and HBx contributed to the nuclear translocation of ANG. Cell proliferation was inhibited after inhibiting the expression or nuclear transfer of ANG.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Vírus da Hepatite B/fisiologia , Interleucina-6/farmacologia , Neoplasias Hepáticas/diagnóstico , Ribonuclease Pancreático/sangue , Regulação para Cima/efeitos dos fármacos , Adulto , Anticorpos/imunologia , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Feminino , Células Hep G2 , Hepatite B/complicações , Hepatite B/diagnóstico , Humanos , Interleucina-6/imunologia , Interleucina-6/metabolismo , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Interferência de RNA , RNA Ribossômico/metabolismo , Ribonuclease Pancreático/antagonistas & inibidores , Ribonuclease Pancreático/genética , Ribonuclease Pancreático/metabolismo , Transativadores/metabolismo , Proteínas Virais Reguladoras e Acessórias
9.
Luminescence ; 33(2): 318-325, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29044942

RESUMO

Here, we have presented a green and facile strategy to fabricate nitrogen-doped carbon dots (N-CDs) and their applications for determination of chlortetracycline (CTC) and sulfasalazine (SSZ). The fluorescent N-CDs, prepared by one-step hydrothermal reaction of citric acid and l-arginine, manifested numerous excellent features containing strong blue fluorescence, good water-solubility, narrow size distribution, and a high fluorescence quantum yield (QY) of 38.8%. Based on the fluorescence quenching effects, the as-synthesized N-CDs as a fluorescent nanosensor exhibited superior analytical performances for quantifying CTC and SSZ. The linear range for CTC was calculated to be from 0.85 to 20.38 µg ml-1 with a low detection limit of 0.078 µg ml-1 . Meanwhile, the linear range for SSZ was estimated to be from 0.34 to 6.76 µg ml-1 with a low detection limit of 0.032 µg ml-1 . Therefore, the N-CDs hold admirable application potential for constructing a fluorescent sensor for pharmaceutical analysis.


Assuntos
Antibacterianos/análise , Carbono/química , Clortetraciclina/análise , Medições Luminescentes/métodos , Pontos Quânticos/química , Sulfassalazina/análise , Fluorescência , Medições Luminescentes/instrumentação , Nitrogênio/química
10.
Int J Mol Sci ; 20(1)2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30577540

RESUMO

Catalytic decomposition of sucrose by acid invertases (AINVs) under acidic conditions plays an important role in the development of sink organs in plants. To reveal the function of AINVs in the development of pepper fruits, nine AINV genes of pepper were identified. Protein sequencing and phylogenetic analysis revealed that the CaAINV family may be divided into cell wall invertases (CaCWINV1⁻7) and vacuolar invertases (CaVINV1⁻2). CaAINVs contain conserved regions and protein structures typical of the AINVs in other plants. Gene expression profiling indicated that CaCWINV2 and CaVINV1 were highly expressed in reproductive organs but differed in expression pattern. CaCWINV2 was mainly expressed in buds and flowers, while CaVINV1 was expressed in developmental stages, such as the post-breaker stage. Furthermore, invertase activity of CaCWINV2 and CaVINV1 was identified via functional complementation in an invertase-deficient yeast. Optimum pH for CaCWINV2 and CaVINV1 was found to be 4.0 and 4.5, respectively. Gene expression and enzymatic activity of CaCWINV2 and CaVINV1 indicate that these AINV enzymes may be pivotal for sucrose hydrolysis in the reproductive organs of pepper.


Assuntos
Capsicum/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Estudo de Associação Genômica Ampla , Família Multigênica , Transcriptoma , beta-Frutofuranosidase/genética , Motivos de Aminoácidos , Sequência de Aminoácidos , Capsicum/classificação , Cromossomos de Plantas , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla/métodos , Imageamento Tridimensional , Modelos Moleculares , Filogenia , Conformação Proteica
11.
Int J Mol Sci ; 19(1)2018 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-29324672

RESUMO

Alkaline/neutral invertase (NINV) proteins irreversibly cleave sucrose into fructose and glucose, and play important roles in carbohydrate metabolism and plant development. To investigate the role of NINVs in the development of pepper fruits, seven NINV genes (CaNINV1-7) were identified. Phylogenetic analysis revealed that the CaNINV family could be divided into α and ß groups. CaNINV1-6 had typical conserved regions and similar protein structures to the NINVs of other plants, while CaNINV7 lacked amino acid sequences at the C-terminus and N-terminus ends. An expression analysis of the CaNINV genes in different tissues demonstrated that CaNINV5 is the dominant NINV in all the examined tissues (root, stem, leaf, bud, flower, and developmental pepper fruits stage). Notably, the expression of CaNINV5 was found to gradually increase at the pre-breaker stages, followed by a decrease at the breaker stages, while it maintained a low level at the post-breaker stages. Furthermore, the invertase activity of CaNINV5 was identified by functional complementation of the invertase-deficient yeast strain SEY2102, and the optimum pH of CaNINV5 was found to be ~7.5. The gene expression and enzymatic activity of CaNINV5 suggest that it might be the main NINV enzyme for hydrolysis of sucrose during pepper fruit development.


Assuntos
Capsicum/genética , Família Multigênica , Proteínas de Plantas/genética , beta-Frutofuranosidase/genética , Capsicum/classificação , Capsicum/enzimologia , Sequência Conservada , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Filogenia , Componentes Aéreos da Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , beta-Frutofuranosidase/metabolismo
12.
Cell Physiol Biochem ; 41(1): 310-322, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28135713

RESUMO

BACKGROUND/AIMS: About 400 million individuals are chronically infected with hepatitis B virus, at high risk of developing liver cirrhosis and hepatocellular carcinoma. Recent studies have demonstrated an interaction between hepatitis B virus replication and autophagy activity of hepatocytes. In the present study, we aimed to investigate the role of miR-141 in regulating autophagy and hepatitis B virus replication. METHODS: The expression of HBV-DNA, miR-141 and Sirt1 mRNA was determined by quantitative real-time PCR analysis. The expression of HBsAg and HBeAg was determined by ELISA. Western blotting was performed to detect protein expression. The LC3 puncta was determined by immunofluorescence. To test whether miR-141 directly regulate the expression level of Sirt1 mRNA, dual-luciferase reporter gene assay was performed. RESULTS: In vitro studies showed that miR-141 mimic inhibited the autophagic response, hepatitis B virus and the expression of Sirt1 in hepatocytes. And transfection with miR-141 inhibitor enhanced autophagic response and Sirt1 expression. The autophagy induced by overexpression of Sirt1 was inhibited by miR-141 mimic. In addition, miR-141 mimic also decreased the expression of Sirt1 mRNA. Sirt1 was predicted as a potential miR-141 target by bioinformatic analysis of its 3'-UTR, and confirmed by luciferase reporter assays which analyzing the interaction of miR-141 with the wild- type or the mutated Sirt1 3'-UTR. CONCLUSION: We have therefore demonstrated a role of miR-141 in regulating autophagy-mediated hepatitis B virus inhibition by targeting Sirt1, and may provide potential targets for drug development.


Assuntos
Autofagia , Vírus da Hepatite B/fisiologia , MicroRNAs/metabolismo , Sirtuína 1/metabolismo , Regiões 3' não Traduzidas , Antagomirs/metabolismo , Sequência de Bases , Linhagem Celular , DNA Viral/metabolismo , Ensaio de Imunoadsorção Enzimática , Genes Reporter , Células HeLa , Células Hep G2 , Antígenos de Superfície da Hepatite B/análise , Antígenos E da Hepatite B/análise , Vírus da Hepatite B/genética , Humanos , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Microscopia de Fluorescência , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Sirtuína 1/antagonistas & inibidores , Sirtuína 1/genética , Replicação Viral
13.
Cell Physiol Biochem ; 36(2): 753-62, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26021263

RESUMO

BACKGROUND: Lipocalin 2 (LCN2), a protein primarily produced by hepatocytes, is highly upregulated under various conditions that induce cellular stress, such as intoxication, infection or inflammation. However, the precise biological functions and underlying mechanisms of LCN2 in hepatocytes remains unknown. METHODS: Hepatocyte stress was successfully induced by treating Huh7 cells with interleukin-1ß (IL-1ß). Interleukin-6 (IL-6), Tumor Necrosis Factor-α (TNF-α) and LCN2 levels were measured in IL-1ß treated Huh7 cells and supernatant. Additionally, microarray analysis was conducted to identify genes differentially expressed in LCN2-silenced and control Huh7 cells. RESULTS: TNF-α, IL-6 and LCN2 were significantly elevated in Huh7 cells after IL-1ß) treatment. In LCN2-silenced Huh7 cells, expression of IL-6 and TNF-α was significantly increased when compared with the expression levels of control Huh7 cells. Furthermore, differentially expressed genes were observed between the LCN2-silenced and control cells. Microarray analysis indicated that LCN2 acted by influencing genes involved in protein metabolism, stress response, cell cycle and proliferation. CONCLUSIONS: Our results suggest that LCN2 upregulation protects hepatocytes from IL-1ß-induced stress. Additionally, our microarray analysis of LCN2-silenced and control cells provides a better understanding of the mechanisms that may be influenced by LCN2 induction.


Assuntos
Proteínas de Fase Aguda/genética , Hepatócitos/imunologia , Interleucina-1beta/imunologia , Lipocalinas/genética , Proteínas Proto-Oncogênicas/genética , Regulação para Cima , Proteínas de Fase Aguda/imunologia , Linhagem Celular , Regulação da Expressão Gênica , Hepatócitos/metabolismo , Humanos , Interleucina-6/genética , Lipocalina-2 , Lipocalinas/imunologia , Proteínas Proto-Oncogênicas/imunologia , Interferência de RNA , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Fator de Necrose Tumoral alfa/genética
14.
NMR Biomed ; 28(9): 1087-96, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26174437

RESUMO

(1)H MRS, (31)P MRS and diffusion-weighted MRI (DW-MRI) were applied to study the metabolic changes associated with estrogen dependence in estrogen receptor (ER)-positive BT-474 and triple-negative HCC1806 breast cancer xenografts supplemented with or without 17ß-estradiol (E2) at a dose of 0.18 or 0.72 mg/pellet. Furthermore, the effect of estrogen withdrawal on the metabolism of BT-474 and HCC1806 breast cancer xenografts was studied on day 0, day 2 and day 10. Increasing the dose of E2 resulted in a rapid growth and increases in the lactate level and phosphomonoester/ß-nucleoside triphosphate (PME/ßNTP), phosphocreatine/inorganic phosphate (PCr/Pi) and ßNTP/Pi ratios in BT-474 breast cancer xenografts; however, no significant changes were found in HCC1806 breast cancer xenografts. Estrogen withdrawal resulted in a marked decrease in lactate level and PME/ßNTP ratio and an observed increase in ßNTP/Pi, PCr/Pi and apparent diffusion coefficient (ADC) values of BT-474 breast cancer xenografts on day 10. These data suggest that the lactate level and PME/ßNTP, PCr/Pi and ßNTP/Pi ratios of ER-positive tumors are closely related to ER dependence.


Assuntos
Neoplasias da Mama/metabolismo , Estradiol/farmacologia , Estrogênios/farmacologia , Espectroscopia de Ressonância Magnética/métodos , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Ácido Láctico/metabolismo , Camundongos , Transplante de Neoplasias , Fosfatos/metabolismo , Fosfocreatina/metabolismo , Transplante Heterólogo
15.
Alzheimer Dis Assoc Disord ; 29(3): 184-191, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25650693

RESUMO

In this study, we investigated the long-term treatment of dantrolene on amyloid and tau neuropathology, brain volume, and cognitive function in aged triple transgenic Alzheimer (3xTg-AD) mice. Fifteen-month old 3xTg-AD mice and wild-type controls were treated with oral dantrolene (5 mg/kg) or vehicle control twice a week for 6 months. Learning and memory were examined using the Morris Water Maze at 21 and 22 months of age. After the behavioral testing, hippocampal and cortical brain volumes were calculated with magnetic resonance imaging and motor function was evaluated using the rotorod. The amyloid burden and tau neurofibrillary tangles in the hippocampus were determined using immunohistochemistry. We found that dantrolene significantly decreased the intraneuronal amyloid accumulation by as much as 76% compared with its corresponding vehicle control, together with a trend to reduce phosphorylated tau in the hippocampus. No significant differences could be detected in hippocampal or cortical brain volume, motor function or cognition among all experimental groups, indicating that the mice were still presymptomatic for Alzheimer disease. Thus, presymptomatic and long-term dantrolene treatment significantly decreased the intraneuronal amyloid burden in aged 3xTg-AD mice before significant changes in brain volume, or cognition.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Dantroleno/farmacologia , Hipocampo/efeitos dos fármacos , Memória/efeitos dos fármacos , Envelhecimento , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Encéfalo/patologia , Transtornos Cognitivos/tratamento farmacológico , Modelos Animais de Doenças , Hipocampo/patologia , Camundongos Transgênicos , Placa Amiloide/tratamento farmacológico
16.
Nanotechnology ; 26(50): 505103, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26584910

RESUMO

Superparamagnetic iron oxide nanoparticles (SPIONs) are promising nanomaterials in medical practice due to their special magnetic characteristics and nanoscale size. However, their potential impacts on immune cells are not well documented. This study aims to investigate the effects of Fe2O3 nanoparticles (Fe2O3-NPs) on the electrophysiology of Kv1.3 channels in Jurkat T cells. Using the whole-cell patch-clamp technique, we demonstrate that incubation of Jurkat cells with Fe2O3-NPs dose- and time-dependently decreased the current density and shifted the steady-state inactivation curve and the recovery curve of Kv1.3 channels to a rightward direction. Fe2O3-NPs increased the NADP level but decreased the NADPH level of Jurkat cells. Direct induction of NADPH into the cytosole of Jurkat cells via the pipette abolished the rightward shift of the inactivation curve. In addition, transmission electron microscopy showed that Fe2O3-NPs could be endocytosed by Jurkat cells with relatively low speed and capacity. Fe2O3-NPs did not significantly affect the viability of Jurkat cells, but suppressed the expressions of certain cytokines (TNFα, IFNγ and IL-2) and interferon responsive genes (IRF-1 and PIM-1), and the time courses of Fe2O3-NPs endocytosis and effects on the expressions of cytokines and interferon responsive genes were compatible. We conclude that Fe2O3-NPs can be endocytosed by Jurkat cells and act intracellularly. Fe2O3-NPs decrease the current density and delay the inactivation and recovery kinetics of Kv1.3 channels in Jurkat cells by oxidizing NADPH and therefore disrupting the redox activity of the Kvß2 auxiliary subunit, and as a result, lead to changes of the Kv1.3 channel function. These results suggest that iron oxide nanoparticles may affect T cell function by disturbing the activity of Kv1.3 channels. Further, the suppressing effects of Fe2O3-NPs on the expressions of certain inflammatory cytokines and interferon responsive genes suggest that iron oxide nanoparticles may exert modulatory effects on T cell immune activities and anti-inflammation effects.


Assuntos
Compostos Férricos/administração & dosagem , Canal de Potássio Kv1.3/metabolismo , Nanopartículas de Magnetita/administração & dosagem , Oxirredução , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Citocinas/metabolismo , Endocitose , Compostos Férricos/química , Humanos , Interferons/genética , Células Jurkat , Canal de Potássio Kv1.3/fisiologia , Nanopartículas de Magnetita/química , Superfamília Shaker de Canais de Potássio
17.
J Antimicrob Chemother ; 69(1): 162-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24004860

RESUMO

OBJECTIVES: The objectives of this study were to determine species distribution and in vitro antifungal susceptibility of Candida isolates identified in the multicentre China-SCAN study of invasive Candida infection (ICI) in intensive care units (ICUs) across China. METHODS: Candida isolates from patients in the China-SCAN study with documented ICI were evaluated by a central laboratory. Species were identified using chromogenic culture media or the API 20C AUX kit. Susceptibility to fluconazole, voriconazole, itraconazole, caspofungin and amphotericin B was determined using the CLSI broth microdilution method (M27-A3) and updated clinical breakpoints or epidemiological cut-off values. RESULTS: A total of 389 isolates from 244 patients were analysed. Species identified most frequently were Candida albicans (40.1%), Candida parapsilosis (21.3%), Candida tropicalis (17.2%) and Candida glabrata (12.9%). Rarer species such as Lodderomyces elongisporus and Candida ernobii were also identified. Fluconazole susceptibility was evident in 85.9% (134/156) of C. albicans, 62.7% (42/67) of C. tropicalis and 48.2% (40/83) of C. parapsilosis isolates. Susceptibility to voriconazole was ≥ 90% among all species. All isolates were susceptible to amphotericin B and caspofungin except C. glabrata [86.0% (43/50) susceptible to caspofungin]. Cross-resistance between fluconazole and voriconazole was observed for C. parapsilosis and C. glabrata. CONCLUSIONS: Although C. albicans was the predominant single species, non-albicans species constituted >50% of isolates. Fluconazole susceptibility was lower in most non-albicans species, indicating that fluconazole resistance should be closely monitored. Susceptibility to voriconazole, amphotericin B and caspofungin is encouraging. Differences between these data and those from other regions emphasize the importance of assessing regional variations.


Assuntos
Antifúngicos/farmacologia , Candida/classificação , Candida/efeitos dos fármacos , Candidíase Invasiva/epidemiologia , Unidades de Terapia Intensiva , Candida/isolamento & purificação , Candidíase Invasiva/microbiologia , China/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Técnicas de Tipagem Micológica
18.
Zhongguo Zhong Yao Za Zhi ; 39(7): 1157-62, 2014 Apr.
Artigo em Zh | MEDLINE | ID: mdl-25011246

RESUMO

Four different extracts of Oxytropis falcata, including the aerial aqueous extract, and the underground aqueous extract, the aerial lipophilic extract, and the underground lipophilic extract were prepared and then administrated orally to mice at the maximum dose (50 g x kg(-1) x d(-1) calculated by raw material) for fifteen days respectively. Compared with the control group, which was administrated of 1.0% tween-80, the treatment groups did not show significant differences in appearance and behavior. However, the organcoefficient, blood biochemical indicator and pathological section results showed that the lipophilic extracts of the aerial and underground parts of O. flacata showed mild injury to the liver of mice, while the aerial and underground aqueous extracts and the underground lipophilic extract showed mild toxicity to the kidney of male mice. Chemical analysis showed that the lipophilic extracts of the aerial and underground parts, especially aerial lipophilic extract, consisted of large amount of flavonoid aglycones with little amount of polysaccharides and proteins, while the aqueous extracts contained much polysaccharides and proteins with almost no flavonoid aglycones detected.


Assuntos
Oxytropis/química , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Feminino , Fígado/efeitos dos fármacos , Fígado/crescimento & desenvolvimento , Masculino , Medicina Tradicional Tibetana , Camundongos , Estrutura Molecular , Tamanho do Órgão/efeitos dos fármacos , Oxytropis/efeitos adversos , Espectrometria de Massas por Ionização por Electrospray
19.
Emerg Microbes Infect ; 12(1): 2219346, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37288745

RESUMO

ABSTRACTGenomes of strains of the zoophilic dermatophyte Microsporum canis from invasive (disseminated and subcutaneous) and noninvasive (tinea capitis) infections were compared. Especially the disseminated strain showed significant syntenic rearrangements, including multiple translocations and inversions, and numerous SNPs and Indels in comparison to the noninvasive strain. In transcriptome analysis, both invasive strains were enriched for GO pathways related to components of the membrane, iron binding and heme binding, which possibly enables them to invade deeper into dermis and blood vessels. At 37 °C, invasive strains showed gene expression enriched for DNA replication, mismatch repair, N-glycan biosynthesis and ribosome biogenesis. The invasive strains were slightly less susceptible to multiple antifungal agents suggesting that acquired elevated drug resistance might be involved in the refractory disease courses. Patient with disseminated infection failed to respond to a combined antifungal treatment with itraconazole, terbinafine, fluconazole and posaconazole.


Assuntos
Tinha do Couro Cabeludo , Transcriptoma , Humanos , Tinha do Couro Cabeludo/tratamento farmacológico , Tinha do Couro Cabeludo/microbiologia , Microsporum/genética , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico
20.
J Diabetes Complications ; 37(4): 108451, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36913875

RESUMO

AIM: We assessed whether omega-3 supplementation could improve glucose and lipid metabolism, insulin resistance, and inflammatory factors in individuals with gestational diabetes mellitus (GDM). METHODS: In this meta-study, we used a random-effects or fixed-effects meta-analysis model to analyze the mean differences (MD) and corresponding 95 % confidence intervals (CI) before and after omega-3 and placebo supplementation, thus evaluating the effects of omega-3 on glucose and lipid metabolism, insulin resistance, and inflammatory factors. RESULTS: Six randomized controlled trials (331 participants) were included in the meta-analysis. The levels of fasting plasma glucose (FPG) (WMD = -0.25 mmol/L; 95 % CI: -0.38, -0.12), fasting insulin (WMD = -17.13 pmol/L; 95 % CI: -27.95, -6.30), and homeostasis model of assessment-insulin resistance (WMD = -0.51; 95 % CI: -0.89, -0.12) were lower in the omega-3 group compared to their levels in the placebo group. The results of the analysis of lipid metabolism showed that triglycerides (WMD = -0.18 mmol/L; 95 % CI: -0.29, -0.08) and very low-density lipoprotein cholesterol (WMD = -0.1 mmol/L; 95 % CI: -0.16, -0.03) decreased in the omega-3 group, while high-density lipoproteins (WMD = 0.06 mmol/L; 95 % CI: 0.02, 0.10) increased. Compared to the placebo group, inflammatory factor serum C-reactive protein (SMD = -0.68 mmol/L; 95 % CI: -0.96, -0.39) decreased in the omega-3 group. CONCLUSION: Omega-3 supplementation can decrease the levels of FPG and inflammatory factors, enhance blood lipid metabolism, and reduce insulin resistance in patients with GDM.


Assuntos
Diabetes Gestacional , Ácidos Graxos Ômega-3 , Resistência à Insulina , Gravidez , Feminino , Humanos , Diabetes Gestacional/tratamento farmacológico , Glucose , Glicemia/metabolismo , Metabolismo dos Lipídeos , Suplementos Nutricionais , Ensaios Clínicos Controlados Aleatórios como Assunto
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