Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Sensors (Basel) ; 24(4)2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38400411

RESUMO

In the process of silicon single-crystal preparation, the timely identification and adjustment of abnormal conditions are crucial. Failure to promptly detect and resolve issues may result in a substandard silicon crystal product quality or even crystal pulling failure. Therefore, the early identification of abnormal furnace conditions is essential for ensuring the preparation of perfect silicon single crystals. Additionally, since the thermal field is the fundamental driving force for stable crystal growth and the primary assurance of crystal quality, this paper proposes a silicon single-crystal growth temperature gradient trend classification algorithm based on multi-level feature fusion. The aim is to accurately identify temperature gradient changes during silicon crystal growth, in order to promptly react to early growth failures and ensure the stable growth of high-quality silicon single crystals to meet industrial production requirements. The algorithm first divides the temperature gradient trend into reasonable categories based on expert knowledge and qualitative analysis methods. Then, it fuses the original features of actual production data, shallow features extracted based on statistical information, and deep features extracted through deep learning. During the fusion process, the algorithm considers the impact of different features on the target variable and calculates mutual information based on the difference between information entropy and conditional entropy, ultimately using mutual information for feature weighting. Subsequently, the fused multi-level feature vectors and their corresponding trend labels are input into a Deep Belief Network (DBN) model to capture process dynamics and classify trend changes. Finally, the experimental results demonstrate that the proposed algorithm can effectively predict the changing trend of thermal field temperature gradients. The introduction of this algorithm will help improve the accuracy of fault trend prediction in silicon single-crystal preparation, thereby minimizing product quality issues and production interruptions caused by abnormal conditions.

2.
J Gastroenterol ; 59(2): 95-108, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37962678

RESUMO

BACKGROUND: Autoimmune gastritis (AIG) is a prevalent chronic inflammatory disease with oncogenic potential that causes destruction of parietal cells and severe mucosal atrophy. We aimed to explore the distinctive gene expression profiles, activated signaling pathways, and their underlying mechanisms. METHODS: A comprehensive gene expression analysis was conducted using biopsy specimens from AIG, Helicobacter pylori-associated gastritis (HPG), and non-inflammatory normal stomachs. Gastric cancer cell lines were cultured under acidic (pH 6.5) conditions to evaluate changes in gene expression. RESULTS: Gastric mucosa with AIG had a unique gene expression profile compared with that with HPG and normal mucosa, such as extensively low expression of ATP4A and high expression of GAST and PAPPA2, which are involved in neuroendocrine tumorigenesis. Additionally, the mucosa with AIG and HPG showed the downregulation of stomach-specific genes and upregulation of small intestine-specific genes; however, intestinal trans-differentiation was much more prominent in AIG samples, likely in a CDX-dependent manner. Furthermore, AIG induced ectopic expression of pancreatic digestion-related genes, PNLIP, CEL, CTRB1, and CTRC; and a master regulator gene of the lung, NKX2-1/TTF1 with alveolar fluid secretion-related genes, SFTPB and SFTPC. Mechanistically, acidic conditions led to the downregulation of master regulator and stemness control genes of small intestine, suggesting that increased environmental pH may cause abnormal intestinal differentiation in the stomach. CONCLUSIONS: AIG induces diverse trans-differentiation in the gastric mucosa, characterized by the transactivation of genes specific to the small intestine, pancreas, and lung. Increased environmental pH owing to AIG may cause abnormal differentiation of the gastric mucosa.


Assuntos
Doenças Autoimunes , Gastrite , Infecções por Helicobacter , Helicobacter pylori , Humanos , Doenças Autoimunes/genética , Gastrite/genética , Gastrite/patologia , Mucosa Gástrica/patologia , Pâncreas/patologia , Transdiferenciação Celular
3.
Gut ; 73(2): 255-267, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37751933

RESUMO

OBJECTIVE: The presence of intestinal metaplasia (IM) is a risk factor for gastric cancer. However, it is still controversial whether IM itself is precancerous or paracancerous. Here, we aimed to explore the precancerous nature of IM by analysing epigenetic alterations. DESIGN: Genome-wide DNA methylation analysis was conducted by EPIC BeadArray using IM crypts isolated by Alcian blue staining. Chromatin immunoprecipitation sequencing for H3K27ac and single-cell assay for transposase-accessible chromatin by sequencing were conducted using IM mucosa. NOS2 was induced using Tet-on gene expression system in normal cells. RESULTS: IM crypts had a methylation profile unique from non-IM crypts, showing extensive DNA hypermethylation in promoter CpG islands, including those of tumour-suppressor genes. Also, the IM-specific methylation profile, namely epigenetic footprint, was present in a fraction of gastric cancers with a higher frequency than expected, and suggested to be associated with good overall survival. IM organoids had remarkably high NOS2 expression, and NOS2 induction in normal cells led to accelerated induction of aberrant DNA methylation, namely epigenetic instability, by increasing DNA methyltransferase activity. IM mucosa showed dynamic enhancer reprogramming, including the regions involved in higher NOS2 expression. NOS2 had open chromatin in IM cells but not in gastric cells, and IM cells had frequent closed chromatin of tumour-suppressor genes, indicating their methylation-silencing. NOS2 expression in IM-derived organoids was upregulated by interleukin-17A, a cytokine secreted by extracellular bacterial infection. CONCLUSIONS: IM cells were considered to have a precancerous nature potentially with an increased chance of converting into cancer cells, and an accelerated DNA methylation induction due to abnormal NOS2 expression.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Lesões Pré-Cancerosas , Neoplasias Gástricas , Humanos , Metilação de DNA , Neoplasias Gástricas/microbiologia , DNA , Cromatina/metabolismo , Metaplasia/genética , Metaplasia/metabolismo , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Mucosa Gástrica/metabolismo , Helicobacter pylori/genética , Infecções por Helicobacter/complicações
4.
Microorganisms ; 11(10)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37894133

RESUMO

The Tibetan Plateau, known as the "Roof of the World" and "The Third Pole", harbors numerous saline lakes primarily distributed in the Northern Tibetan Plateau. However, the challenging conditions of high altitude, low oxygen level, and harsh climate have limited investigations into the actinobacteria from these saline lakes. This study focuses on investigating the biodiversity and bioactive secondary metabolites of cultivable actinobacteria isolated from the sediments of four saline lakes on the Northern Tibetan Plateau. A total of 255 actinobacterial strains affiliated with 21 genera in 12 families of 7 orders were recovered by using the pure culture technique and 16S rRNA gene phylogenetic analysis. To facilitate a high-throughput bioactivity evaluation, 192 isolates underwent OSMAC cultivation in a miniaturized 24-well microbioreactor system (MATRIX cultivation). The antibacterial activity of crude extracts was then evaluated in a 96-well plate antibacterial assay. Forty-six strains demonstrated antagonistic effects against at least one tested pathogen, and their underlying antibacterial mechanisms were further investigated through a dual-fluorescent reporter assay (pDualrep2). Two Streptomyces strains (378 and 549) that produce compounds triggering DNA damage were prioritized for subsequent chemical investigations. Metabolomics profiling involving HPLC-UV/vis, UPLC-QTOF-MS/MS, and molecular networking identified three types of bioactive metabolites belonging to the aromatic polyketide family, i.e., cosmomycin, kidamycin, and hedamycin. In-depth analysis of the metabolomic data unveiled some potentially novel anthracycline compounds. A genome mining study based on the whole-genome sequences of strains 378 and 549 identified gene clusters potentially responsible for cosmomycin and kidamycin biosynthesis. This work highlights the effectiveness of combining metabolomic and genomic approaches to rapidly identify bioactive chemicals within microbial extracts. The saline lakes on the Northern Tibetan Plateau present prospective sources for discovering novel actinobacteria and biologically active compounds.

5.
Breast Cancer Res Treat ; 201(2): 317-328, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37378696

RESUMO

PURPOSE: HER2-positive breast cancer has a high chance of achieving pathological complete response when HSD17B4, responsible for peroxisomal ß-oxidation of very long-chain fatty acids (VLCFA) and estradiol, is methylation-silenced. Here, we aimed to identify the underlying molecular mechanism. METHODS: Using a HER2-positive breast cancer cell line, BT-474, control and knock-out (KO) clones were obtained. Metabolic characteristics were analyzed using a Seahorse Flux analyzer. RESULTS: HSD17B4 KO suppressed cellular proliferation, and enhanced sensitivity to lapatinib approximately tenfold. The KO led to accumulation of VLCFA and a decrease of polyunsaturated fatty acids (PUFAs), such as docosahexaenoic acid (DHA) and arachidonic acid. HSD17B4 KO increased Akt phosphorylation, possibly via decreased DHA, and genes involved in oxidative phosphorylation (OxPhos) and electron transport chain (ETC) were upregulated. Increased mitochondrial ATP production in the KO cells was confirmed by extracellular flux analyzer. Increased OxPhos led to severe dependence of the KO cells on pyruvate from glycolysis. Suppression of glycolysis by lapatinib led to severe delayed suppression of OxPhos in KO cells. CONCLUSION: HSD17B4 KO in BT-474 cells caused a decrease of PUFAs, increased Akt phosphorylation, enhanced glucose dependence of OxPhos, and increased sensitivity to inhibition of HER2, upstream of Akt. This mechanism may be applicable to other HER2-positive glucose-dependent breast cancer cells with HSD17B4 silencing.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Lapatinib/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Metilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Glucose , Linhagem Celular Tumoral , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Proteína Multifuncional do Peroxissomo-2/genética , Proteína Multifuncional do Peroxissomo-2/metabolismo
6.
Methods Mol Biol ; 2691: 165-183, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37355545

RESUMO

DNA methylation of promoter CpG islands silences their downstream genes, and enhancer methylation can be associated with decreased or increased gene expression. DNA methylation alterations in normal and diseased cells provide rich information, such as tissue origin, disease risk, patient response, and prognosis. DNA methylation status is detected by bisulfite conversion, which converts unmethylated cytosines into uracils but methylated cytosines very inefficiently. A genome-wide DNA methylation analysis is conducted by a BeadChip microarray or next-generation sequencing (NGS) of bisulfite-treated DNA. A region-specific DNA methylation analysis can be conducted by various methods, such as methylation-specific PCR (MSP), quantitative MSP, and bisulfite sequencing. This chapter provides protocols for bisulfite-mediated conversion, a BeadChip array-based method (Infinium), quantitative MSP, and bisulfite sequencing.


Assuntos
Metilação de DNA , Sulfitos , Humanos , Análise de Sequência de DNA/métodos , Ilhas de CpG
7.
Gastric Cancer ; 26(5): 667-676, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37219707

RESUMO

BACKGROUND: Gastric cancer risk can be accurately predicted by measuring the methylation level of a single marker gene in gastric mucosa. However, the mechanism is still uncertain. We hypothesized that the methylation level measured reflects methylation alterations in the entire genome (methylation burden), induced by Helicobacter pylori (H. pylori) infection, and thus cancer risk. METHODS: Gastric mucosa of 15 healthy volunteers without H. pylori infection (G1), 98 people with atrophic gastritis (G2), and 133 patients with gastric cancer (G3) after H. pylori eradication were collected. Methylation burden of an individual was obtained by microarray analysis as an inverse of the correlation coefficient between the methylation levels of 265,552 genomic regions in the person's gastric mucosa and those in an entirely healthy mucosa. RESULTS: The methylation burden significantly increased in the order of G1 (n = 4), G2 (n = 18), and G3 (n = 19) and was well correlated with the methylation level of a single marker gene (r = 0.91 for miR124a-3). The average methylation levels of nine driver genes tended to increase according to the risk levels (P = 0.08 between G2 vs G3) and was also correlated with the methylation level of a single marker gene (r = 0.94). Analysis of more samples (14 G1, 97 G2, and 131 G3 samples) yielded significant increases of the average methylation levels between risk groups. CONCLUSIONS: The methylation level of a single marker gene reflects the methylation burden, which includes driver gene methylation, and thus accurately predicts cancer risk.


Assuntos
Gastrite Atrófica , Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Metilação de DNA , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Mucosa Gástrica/metabolismo , Gastrite Atrófica/genética , Fatores de Risco , Infecções por Helicobacter/complicações , Infecções por Helicobacter/genética
8.
J Org Chem ; 88(3): 1403-1410, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36656018

RESUMO

A nickel-catalyzed three-component tandem radical cyclization reaction of aryl bromides with 1,3-enynes and aryl boric acids to construct γ-lactam-substituted allene derivatives has been described. This protocol provides lactam alkyl radicals through the free radical cyclization process, which can be effectively used to participate in the subsequent multicomponent coupling reaction so that 1,3-enynes could directly convert into corresponding poly-substituted allene compounds. In addition, this efficient method enjoys a broad substrate scope and provides a series of 1,5-difunctionalized allenes in a one-pot reaction.

9.
Cardiovasc Res ; 119(7): 1606-1618, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-36537041

RESUMO

AIMS: Endothelial-to-mesenchymal transition (EndMT) is a fundamental process in vascular remodelling. However, the precise regulatory mechanism of vascular remodelling during neointima formation and the source of neointima cells are not entirely understood. METHODS AND RESULTS: To investigate the origin of neointima cells and their relevance to vascular wall remodelling, we used an endothelial cell (EC)-specific lineage tracing system [VE-Cadherin (Cdh5)-BAC-CreERT2 mice] and carotid artery ligation model and showed evidence that resident ECs transdifferentiate into neointima cells with the expression of CD45. During the early stages of neointima formation, ECs transiently expressed CD45, a haematopoietic marker, accompanied by a host of EndMT markers, and CD31 and αSMA were prominently expressed in developing neointima. In vitro, CD45-positive EndMT was induced by stabilization of HIF1α with cobalt chloride or with a VHL inhibitor in human primary ECs, which mimicked the hypoxic condition of the ligated artery, and promoted the formation of an integrin α11-shank-associated RH domain-interacting protein (SHARPIN) complex. Notably, a CD45 phosphatase inhibitor disrupted this integrin α11-SHARPIN complex, thereby destabilizing cell-cell junctions. Deletion of Hif1α in ECs suppressed expression of CD45 and EndMT markers and ameliorated neointima formation. CONCLUSION: These results suggest that the HIF-induced CD45 expression is normally required for the retention of an EC fate and cell-cell junctions, CD45-positive EndMT (termed as 'partial EndMT') contributes to neointima formation and vascular wall remodelling.


Assuntos
Neointima , Remodelação Vascular , Animais , Humanos , Camundongos , Artérias Carótidas/cirurgia , Células Cultivadas , Endotélio , Transição Epitelial-Mesenquimal , Integrinas , Antígenos Comuns de Leucócito/metabolismo
10.
Proc Natl Acad Sci U S A ; 119(31): e2123241119, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35895679

RESUMO

Somatic mutations are accumulated in normal human tissues with aging and exposure to carcinogens. If we can accurately count any passenger mutations in any single DNA molecule, since their quantity is much larger than driver mutations, we can sensitively detect mutation accumulation in polyclonal normal tissues. Duplex sequencing, which tags both DNA strands in one DNA molecule, enables accurate count of such mutations, but requires a very large number of sequencing reads for each single sample of human-genome size. Here, we reduced the genome size to 1/90 using the BamHI restriction enzyme and established a cost-effective pipeline. The enzymatically cleaved and optimal sequencing (EcoSeq) method was able to count somatic mutations in a single DNA molecule with a sensitivity of as low as 3 × 10-8 per base pair (bp), as assessed by measuring artificially prepared mutations. Taking advantages of EcoSeq, we analyzed normal peripheral blood cells of pediatric sarcoma patients who received chemotherapy (n = 10) and those who did not (n = 10). The former had a mutation frequency of 31.2 ± 13.4 × 10-8 per base pair while the latter had 9.0 ± 4.5 × 10-8 per base pair (P < 0.001). The increase in mutation frequency was confirmed by analysis of the same patients before and after chemotherapy, and increased mutation frequencies persisted 46 to 64 mo after chemotherapy, indicating that the mutation accumulation constitutes a risk of secondary leukemia. EcoSeq has the potential to reveal accumulation of somatic mutations and exposure to environmental factors in any DNA samples and will contribute to cancer risk estimation.


Assuntos
Análise Mutacional de DNA , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Taxa de Mutação , Imagem Individual de Molécula , Envelhecimento/genética , Pareamento de Bases , Criança , Análise Mutacional de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Mutação , Imagem Individual de Molécula/métodos
11.
J Gastroenterol ; 57(3): 144-155, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35034200

RESUMO

BACKGROUND: Autoimmune gastritis (AIG) is a chronic inflammatory condition in gastric mucosa and is associated with increased cancer risk, though not as high as that by Helicobacter pylori (H. pylori)-associated gastritis (HPG). Although aberrant DNA methylation is induced by HPG and the level correlates with the risk of gastric cancer, DNA methylation induction by AIG is unknown. METHODS: Gastric mucosa samples from the corpus were collected from 12 people with AIG without H. pylori infection, 10 people with HPG, and eight healthy volunteers. Genome-wide DNA methylation analysis was conducted using Infinium Methylation EPIC array. Gene expression was analyzed by quantitative RT-PCR. RESULTS: The AIG samples had extensive aberrant DNA methylation but presented unique methylation profiles against the HPG samples after correction of leucocyte fractions. Comparison between the AIG and HPG samples showed that AIG induced methylation, but less than HPG, in overall CpG sites and also in promoter CpG islands. Promoter CpG islands of tumor-suppressor genes in the pathway of cell cycle, cell adhesion, p53, and WNT were highly methylated in the AIG samples, but more so in the HPG samples. The expression levels of IL1B and IL8, secreted by macrophage, were significantly lower in the AIG samples than in the HPG samples, suggesting that a difference in inflammatory response affected the degree and patterns of aberrant DNA methylation. CONCLUSIONS: AIG induced aberrant DNA methylation in gastric mucosa. However, the degree of DNA methylation was less than that by HPG, which reflected carcinogenic risk.


Assuntos
Gastrite , Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Carcinógenos , Ilhas de CpG/genética , Metilação de DNA , Mucosa Gástrica/metabolismo , Gastrite/complicações , Gastrite/genética , Infecções por Helicobacter/complicações , Infecções por Helicobacter/genética , Infecções por Helicobacter/metabolismo , Humanos , Neoplasias Gástricas/metabolismo
12.
Gastric Cancer ; 25(2): 336-345, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34557982

RESUMO

BACKGROUND: Prediction of tissue origin of esophagogastric junction (EGJ) adenocarcinomas can be important for therapeutic decision, but no molecular marker is available. Here, we aimed to develop such a marker taking advantage of tissue-specific profiles of DNA methylation. METHODS: DNA methylation profiles of gastric adenocarcinomas (GACs) were obtained by an Infinium HumanMethylation450 BeadChip array, and those of esophageal adenocarcinoma (EACs) were obtained from the TCGA database. DNA from formalin-fixed paraffin-embedded (FFPE) samples was analyzed by bisulfite pyrosequencing. RESULTS: In the screening set, 51 of 145,841 CpG sites in CpG islands were methylated at significantly higher levels in 30 GACs compared to those in 30 EACs. Among them, SLC46A3 and cg09177106 were unmethylated in all the 30 EACs. Predictive powers of these two markers were successfully confirmed in an independent validation set (18 GACs and 18 EACs) (SLC46A3, sensitivity = 77.8%, specificity = 100%; cg09177106, sensitivity = 83.3%, specificity = 94.4%), and could be applied to FFPE samples (37 GACs and 18 EACs) (SLC46A3, P = 0.0001; cg09177106, P = 0.0028). On the other hand, EAC-specific markers informative in the FFPE samples could not be isolated. Using these GAC-specific markers, nine of 46 (19.6%) TCGA EGJ adenocarcinomas were predicted to be GACs. CONCLUSIONS: Two GAC-specific markers, SLC46A3 and cg09177106, had a high specificity for identifying the tissue origin of EGJ adenocarcinoma.


Assuntos
Adenocarcinoma , Neoplasias Esofágicas , Neoplasias Gástricas , Adenocarcinoma/genética , Adenocarcinoma/patologia , Metilação de DNA , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Junção Esofagogástrica/patologia , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia
13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(5): 1504-1509, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34627431

RESUMO

OBJECTIVE: To investigate the effect of arsenic disulfide (AS2S2) combined with itraconazole on the proliferation, apoptosis and hedgehog pathway of diffuse large B-cell lymphoma (DLBCL) cells. METHODS: The human DLBCL cell OCI-LY3 was treated with different concentrations of AS2S2 and itraconazole. Cell proliferation inhibition was detected by CCK-8, cell apoptosis rate was determined by flow cytometry. The expression levels of BCL-2, BAX, SMO and GLi1 were detected by Western blot. RESULTS: The DLBCL cell viability was decreased significantly at 24, 48 or 72 h as cultured with itraconazole. Along with the increasing of itraconazole concentration, the DLBCL cell viability was significantly reduced as compared with that in control group, and the results showed statistically significant(r=-0.690,r=-0.639, r=-0.833, r=-0.808, r=-0.578). The inhibitory and apoptosis rates of the cells were significantly increased as compared with those of the single drug-treated group after treated by the combination of itraconazole and AS2S2(P<0.05). The protein levels of SMO and Glil were significantly down-regulated after treated by arsenic disulfide and itraconazole alone(P<0.01). The protein expression levels of SMO and Glil was down-regulated in the combined-treatment group(P<0.01). CONCLUSION: Itraconazole can inhibit proliferation of DLBCL cells in a concentration-and time-dependent manner. In addition, the combination of AS2S2 and itraconazole show a synergistic effects, which may be related with the down-regulated protein expression of SMO and Glil of Hedgehog signaling pathway.


Assuntos
Proteínas Hedgehog , Linfoma Difuso de Grandes Células B , Apoptose , Arsenicais , Humanos , Itraconazol/farmacologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Sulfetos
14.
Sci Rep ; 10(1): 15530, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32968149

RESUMO

HER2-positive breast cancers that achieve pathological complete response (pCR) after HER2-directed therapy consistently have good survival. We previously identified HSD17B4 methylation as a marker for pCR by methylation screening. Here, we aimed to identify a new marker by conducting a multi-omics analysis of materials prepared by laser capture microdissection, and adding 71 new samples. In the screening set (n = 36), mutations, methylation, and expression were analyzed by targeted sequencing, Infinium 450 K, and expression microarray, respectively, and 15 genes were identified as differentially expressed and eight genomic regions as differentially methylated between cancer samples with and without pCR. In a validation set (n = 47), one gene showed differential expression, and one region had differential methylation. Further, in the re-validation set (n = 55), all new samples, only HSD17B4 methylation was significantly different. The HSD17B4 methylation was at the transcriptional start site of its major variant, and was associated with its silencing. HSD17B4 was highly expressed in the vast majority of human cancers, and its methylation was present only in breast cancers and one lymphoblastic leukemia cell line. A combination of estrogen receptor-negative status and HSD17B4 methylation showed a positive predictive value of 80.0%. During HER2-directed neoadjuvant therapy, HSD17B4 methylation was the most reliable marker to monitor response to the therapy. These results showed that HSD17B4 methylation is a candidate predictive and response marker of HER2-positive breast cancer to HER2-directed therapy.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais , Neoplasias da Mama/genética , Proteína Multifuncional do Peroxissomo-2/genética , Receptor ErbB-2/genética , Biomarcadores Tumorais/genética , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Metilação de DNA , DNA de Neoplasias/genética , Feminino , Inativação Gênica , Humanos , Pessoa de Meia-Idade , Receptor ErbB-2/antagonistas & inibidores , Transcriptoma , Resultado do Tratamento
15.
Cancer Sci ; 111(11): 4276-4287, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32860304

RESUMO

End-stage renal disease (ESRD) patients on dialysis therapy have a higher incidence of renal cell carcinomas (RCCs), which consist of 2 major histopathological types: clear-cell RCCs (ESRD-ccRCCs) and acquired cystic disease (ACD)-associated RCCs. However, their genetic and epigenetic alterations are still poorly understood. Here, we investigated somatic mutations, copy number alterations (CNAs), and DNA methylation profiles in 9 ESRD-ccRCCs and 7 ACD-associated RCCs to identify their molecular alterations and cellular origins. Targeted sequencing of 409 cancer-related genes, including VHL, PBRM1, SETD2, BAP1, KDM5C, MET, KMT2C (MLL3), and TP53, showed ESRD-ccRCCs harbored frequent VHL mutations, while ACD-associated RCCs did not. CNA analysis showed that ESRD-ccRCCs had a frequent loss of chromosome 3p while ACD-associated RCCs had a gain of chromosome 16. Beadarray methylation analysis showed that ESRD-ccRCCs had methylation profiles similar to those of sporadic ccRCCs, while ACD-associated RCCs had profiles similar to those of papillary RCCs. Expression analysis of genes whose expression levels are characteristic to individual segments of a nephron showed that ESRD-ccRCCs and ACD-associated RCCs had high expression of proximal tubule cell marker genes, while chromophobe RCCs had high expression of distal tubule cell/collecting duct cell marker genes. In conclusion, ESRD-ccRCCs and ACD-associated RCCs had mutation and methylation profiles similar to those of sporadic ccRCCs and papillary RCCs, respectively, and these 2 histopathological types of RCCs were indicated to have originated from proximal tubule cells of the nephron.


Assuntos
Epigênese Genética , Predisposição Genética para Doença , Falência Renal Crônica/complicações , Falência Renal Crônica/genética , Neoplasias Renais/etiologia , Neoplasias Renais/patologia , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Adulto , Idoso , Carcinoma de Células Renais/etiologia , Carcinoma de Células Renais/patologia , Variações do Número de Cópias de DNA , Epigenoma , Feminino , Perfilação da Expressão Gênica , Genótipo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mutação , Transcriptoma
16.
Sensors (Basel) ; 20(6)2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32197503

RESUMO

For total knee replacement (TKR) patients, rehabilitation after the surgery is key toregaining mobility. This study proposes a sensor-based system for effectively monitoringrehabilitation progress after TKR. The system comprises a hardware module consisting of thetriaxial accelerometer and gyroscope, a microcontroller, and a Bluetooth module, and a softwareapp for monitoring the motion of the knee joint. Three indices, namely the number of swings, themaximum knee flexion angle, and the duration of practice each time, were used as metrics tomeasure the knee rehabilitation progress. The proposed sensor device has advantages such asusability without spatiotemporal constraints and accuracy in monitoring the rehabilitation progress.The performance of the proposed system was compared with the measured range of motion of theCybex isokinetic dynamometer (or Cybex) professional rehabilitation equipment, and the resultsrevealed that the average absolute errors of the measured angles were between 1.65° and 3.27° forthe TKR subjects, depending on the swing speed. Experimental results verified that the proposedsystem is effective and comparable with the professional equipment.


Assuntos
Artroplastia do Joelho/reabilitação , Técnicas Biossensoriais , Articulação do Joelho/fisiologia , Monitorização Fisiológica , Amplitude de Movimento Articular/fisiologia , Recuperação de Função Fisiológica/fisiologia , Acelerometria/instrumentação , Acelerometria/métodos , Actigrafia/instrumentação , Actigrafia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aplicativos Móveis , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Modalidades de Fisioterapia/instrumentação , Rotação , Telemedicina/instrumentação , Telemedicina/métodos , Telemetria/instrumentação , Telemetria/métodos , Resultado do Tratamento , Dispositivos Eletrônicos Vestíveis , Adulto Jovem
17.
J Asian Nat Prod Res ; 22(5): 434-443, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31791147

RESUMO

Various bioactive polyketides have been found in Aloe barbadensis. However, the polyketide synthases (PKSs), which participate in biosynthesis of polyketides in A. barbadensis remain unknown. In this study, two type III PKSs (AbPKS1 and AbPKS2) were identified from A. barbadensis. AbPKS1 and AbPKS2 were able to utilize malonyl-CoA to yield heptaketides (TW93a and aloesone) and octaketides (SEK4 and SEK4b), respectively. AbPKS1 also exhibited catalytic promiscuity in recognizing CoA thioesters of aromatics to produce unusual polyketides. What Is more, a whole cell biocatalysis system with the capability of producing 26.4 mg/L of SEK4/SEK4b and 2.1 mg/L of aloesone was successfully established.


Assuntos
Aloe , Policetídeos , Aciltransferases , Estrutura Molecular , Policetídeo Sintases
18.
Int J Oncol ; 54(6): 1907-1920, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31081062

RESUMO

The p53 protein is a tumour suppressor and transcription factor that regulates the expression of target genes involved in numerous stress responses systems. In this study, we designed a screening strategy using DNA damage­induced mouse and human transcriptome data to identify novel downstream targets of p53. Our method selected genes with an induced expression in multiple organs of X­ray­irradiated p53 wild­type mice. The expression of inka box actin regulator 2 gene, known as Inka2, was upregulated in 12 organs when p53 expression was induced. Similarly, INKA2 was induced in a p53­dependent manner at both the mRNA and protein level in human cells treated with adriamycin. Reporter assays confirmed that p53 directly regulated INKA2 through an intronic binding site. The overexpression of INKA2 produced a slight decrease in cancer cell growth in the colony formation assay. Moreover, the analysis of The Cancer Genome Atlas (TCGA) data revealed a decreased INKA2 expression in tumour samples carrying p53 mutations compared with p53 wild­type samples. In addition, significantly higher levels of DNA methylation were observed in the INKA2 promoter in tumour samples, concordant with the reduced INKA2 expression in tumour tissues. These results demonstrate the potential of INKA2 as a cancer cell growth inhibitor. Furthermore, INKA2 protein interacts with the serine/threonine­protein kinase, p21 (RAC1) activated kinase (PAK)4, which phosphorylates ß­catenin to prevent ubiquitin­proteasomal degradation. As ß­catenin was downregulated in a stable INKA2­expressing cell line, the findings of this study suggest that INKA2 is a novel, direct downstream target of p53 that potentially decreases cell growth by inhibiting the PAK4­ß­catenin pathway.


Assuntos
Perfilação da Expressão Gênica/métodos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias/genética , Proteína Supressora de Tumor p53/metabolismo , Quinases Ativadas por p21/metabolismo , Animais , Linhagem Celular Tumoral , Metilação de DNA , Doxorrubicina/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos da radiação , Células HCT116 , Humanos , Camundongos , Mutação , Neoplasias/metabolismo , Fosforilação , Regiões Promotoras Genéticas , Análise de Sequência de RNA/métodos , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , beta Catenina/metabolismo
19.
J Phys Chem A ; 123(13): 2789-2795, 2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30865457

RESUMO

Blue-light-emitting semiconductors based on polyfluorenes often exhibit an undesired green emission band. In this report, three well-defined oligofluorenes corresponding to three types of "defects" attributed to aggregation, keto formation, and chain entanglement, respectively, are systemically investigated to unveil the origins of the green emission band in fluorene-based materials. First, the optical properties of defect molecules in different states are studied. The defect associated with aggregation is absent in dilute solutions and in films doped at 0.01 wt % with poly(methyl methacrylate). Second, the dependence of the emission spectra on the solvent was monitored to compare the effects of the "keto-" and "chain-entanglement defect" molecules. The green emission of keto defects exhibited a strong dependence on solvent polarity, whereas this cannot be observed in case of chain-entanglement defect. Third, energy transfer between poly[4-(octyloxy)-9,9-diphenylfluoren-2,7-diyl]- co-[5-(octyloxy)-9,9-diphenyl-fluoren-2,7-diyl] and the keto or chain-entanglement defect molecules is illustrated. Compared to those of the chain-entanglement defect, the spectra of the keto defect molecule (1:10-3) show signs of defect emission at lower proportions. These investigations not only provide insight into the photophysics of oligofluorenes but also supply a new strategy to explore defects in semiconductor polymers, which will aid in the development of effective approaches to obtain stable, pure blue organic light-emitting diodes based on polyfluorenes.

20.
Acta Pharmacol Sin ; 39(4): 633-641, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29323335

RESUMO

Glucocorticoid (GC)-induced osteoporosis (GIO) is characterized by impaired bone formation, which can be alleviated by tanshinol, an aqueous polyphenol isolated from Salvia miltiorrhiza Bunge. In this study we investigated the molecular mechanisms underlying GC-induced modulation of osteogenesis as well as the possibility of using tanshinol to interfere with GIO. Female SD rats aged 4 months were orally administered distilled water (Con), prednisone (GC, 5 mg·kg-1·d-1), GC plus tanshinol (Tan, 16 mg·kg-1·d-1) or GC plus resveratrol (Res, 5 mg·kg-1·d-1) for 14 weeks. After the rats were sacrificed, samples of bone tissues were collected. The changes in bone formation were assessed using Micro-CT, histomorphometry, and biomechanical assays. Expression of Kruppel-like factor 15 (KLF15), peroxisome proliferator-activated receptor γ 2 (PPARγ 2) and other signaling proteins in skeletal tissue was measured with Western blotting and quantitative RT-PCR. GC treatment markedly increased the expression of KLF15, PPARγ2, C/EBPα and aP2, which were related to adipogenesis, upregulated FoxO3a pathway proteins (FoxO3a and Gadd45a), and suppressed the canonical Wnt signaling (ß-catenin and Axin2), which was required for osteogenesis. Thus, GC significantly decreased bone mass and bone quality. Co-treatment with Tan or Res effectively counteracted GC-impaired bone formation, suppressed GC-induced adipogenesis, and restored abnormal expression of the signaling molecules in GIO rats. We conclude that tanshinol counteracts GC-decreased bone formation by inhibiting marrow adiposity via the KLF15/PPARγ2/FoxO3a/Wnt pathway.


Assuntos
Adipogenia/efeitos dos fármacos , Ácidos Cafeicos/uso terapêutico , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Via de Sinalização Wnt/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Medula Óssea/metabolismo , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Regulação para Baixo , Proteínas de Ligação a Ácido Graxo/genética , Feminino , Proteína Forkhead Box O3/genética , Fatores de Transcrição Kruppel-Like/genética , PPAR gama/genética , Prednisona/administração & dosagem , Prednisona/farmacologia , Ratos Sprague-Dawley , Resveratrol , Estilbenos/administração & dosagem , Estilbenos/farmacologia , Regulação para Cima , Via de Sinalização Wnt/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...