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1.
Ren Fail ; 45(2): 2290365, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38087473

RESUMO

OBJECTIVE: This study was to assess the safety and effectiveness of immunosuppressive agents, specifically Voclosporin, when used in conjunction with mycophenolate mofetil (MMF) induction therapy for the management of lupus nephritis (LN). METHODS: A systematic review and network meta-analysis (NMA) was conducted on randomized controlled trials investigating the efficacy of immunosuppressant-induced therapy for LN. The random effects model was used in the analysis. I2 was used to evaluate the heterogeneity of the model. Odds ratios (OR) and 95% credible intervals (CrI) were computed to assess and compare the relative effectiveness and safety of various treatment protocols. RESULTS: The study included a total of 16 randomized controlled trials (RCTs) involving 2444 patients with LN. The analysis results indicated that there was no significant difference in terms of partial remission (PR) between the drugs. However, when considering complete remission (CR), the combination of Voclosporin with MMF showed the highest remission rate, followed by Tacrolimus (TAC). Unfortunately, Voclosporin in combination with MMF had the highest risk of infection and serious infection, indicating a lower safety profile. CONCLUSIONS: Voclosporin in combination with MMF demonstrated the highest efficacy as an induction therapy for LN. However, it should be noted that the risk of infection and serious infection was found to be high with this regimen. On the other hand, TAC not only showed efficacy but also had a lower risk of infection and serious infection, making it a favorable option in terms of safety. This study did' not include results on other adverse events.


Assuntos
Nefrite Lúpica , Humanos , Nefrite Lúpica/tratamento farmacológico , Ciclofosfamida/uso terapêutico , Quimioterapia de Indução , Metanálise em Rede , Resultado do Tratamento , Imunossupressores/efeitos adversos , Tacrolimo/efeitos adversos , Ácido Micofenólico/efeitos adversos , Indução de Remissão , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
Genome Res ; 29(1): 74-84, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30552104

RESUMO

Repair of UV-induced DNA damage requires chromatin remodeling. How repair is initiated in chromatin remains largely unknown. We recently demonstrated that global genome-nucleotide excision repair (GG-NER) in chromatin is organized into domains in relation to open reading frames. Here, we define these domains, identifying the genomic locations from which repair is initiated. By examining DNA damage-induced changes in the linear structure of nucleosomes at these sites, we demonstrate how chromatin remodeling is initiated during GG-NER. In undamaged cells, we show that the GG-NER complex occupies chromatin, establishing the nucleosome structure at these genomic locations, which we refer to as GG-NER complex binding sites (GCBSs). We demonstrate that these sites are frequently located at genomic boundaries that delineate chromosomally interacting domains (CIDs). These boundaries define domains of higher-order nucleosome-nucleosome interaction. We demonstrate that initiation of GG-NER in chromatin is accompanied by the disruption of dynamic nucleosomes that flank GCBSs by the GG-NER complex.


Assuntos
Montagem e Desmontagem da Cromatina/fisiologia , Reparo do DNA/fisiologia , Regulação Fúngica da Expressão Gênica/fisiologia , Genoma Fúngico/fisiologia , Nucleossomos , Saccharomyces cerevisiae , Nucleossomos/genética , Nucleossomos/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
3.
Exp Eye Res ; 202: 108282, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33049272

RESUMO

Posterior capsule opacification (PCO) after cataract surgery is one of the leading causes of visual impairment and blindness. The cause of PCO is the capsule fibrosis developed on implanted Intraocular Lens (IOLs) by the de-differentiation of Lens Epithelial Cells (LECs) undergoing epithelial mesenchymal transition. How to prevent PCO has been a challenge to scientists and ophthalmologists for decades. Here we demonstrated the use of carboxylated CuInS/ZnS quantum dots (ZCIS QDs), which are free of toxic heavy metals and are more biocompatible, as photothermal nanomedicines. The ZCIS QDs are modified onto the non-optical section of IOLs by a facial activation-immersion method. Under mild NIR laser irradiation, ZCIS QDs modified IOLs (QDs-IOLs) will generate localized heat and prevent the proliferation of LECs onto the surface of QDs-IOLs. Our findings provide experimental evidence for further application of combined nanotechnology and photothermal therapy for the clinical treatment of PCO.


Assuntos
Ligas/química , Opacificação da Cápsula/terapia , Lentes Intraoculares , Terapia Fototérmica/métodos , Pontos Quânticos/química , Sulfetos/química , Compostos de Zinco/química , Animais , Apoptose , Materiais Biocompatíveis , Linhagem Celular , Sobrevivência Celular , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Fibroblastos/efeitos dos fármacos , Cristalino/citologia , Camundongos , Microscopia Eletrônica de Transmissão , Cápsula Posterior do Cristalino
4.
Pharmacology ; 105(5-6): 360-368, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31671426

RESUMO

BACKGROUND: Berberine is a promising natural drug that has a potential therapeutic effect on neurodegenerative diseases. OBJECTIVES: Using U251 cells in vitro, we investigated whether berberine exerts its neuroprotective effect via regulation of CYP2J2. METHOD: After pretreatment with increasing concentrations (1, 3, and 10 µmol/L) of berberine for 0.5 h, U251 cells were stimulated with 1 µg/mL of lipopolysaccharide (LPS). Cell viability was measured 24 h later using a CCK8 kit. mRNA and protein levels of CYP2J2 and peroxisome proliferator-activated receptor alpha (PPARα) were measured by quantitative real-time-polymerase chain reaction and western blotting, respectively, after 24 h of exposure to 1, 3, or 10 µmol/L berberine. Fluorescence immunocytochemistry was also used to evaluate PPARα protein expression after treatment of U251 cells with 10-µmol/L berberine for 24 h. Transient transfection (cotransfection with the plasmid of PPARα- and RXRα-containing) followed by luciferase and chromatin immunoprecipitation assays was used to elucidate the molecular mechanism underlying the observed effects. RESULTS: Compared to the control, LPS-induced U251 cell death was attenuated by berberine in a dose-dependent manner. After 24 h, cell viability was found to be 52.3% (p < 0.05), 66.2% (p < 0.01), and 70.9% (p < 0.001) using 1, 3, and 10 µmol/L berberine treatment, respectively. At these concentrations, berberine increased the CYP2J2 mRNA levels by 1.31-fold (p < 0.05), 1.48-fold (p < 0.01), and 1.88-fold (p < 0.01), respectively, and increased the PPARα mRNA levels 1.17-fold (p < 0.05), 1.29-fold (p < 0.05), and 1.53-fold (p < 0.01), respectively, compared with the respective control groups. In addition, the CYP2J2 and PPARα protein level was also significantly upregulated in U251 cells by berberine (concentrations in 1, 3, and 10 µmol/L) in a dose-dependent manner, compared with the respective control groups. Further investigation indicated that berberine enhances the heterodimerization of PPARα and RXRα, which together bind to the CYP2J2 promoter to induce the expression of CYP2J2 in U251 cells. CONCLUSION: Upon exposure of U251 cells to berberine, CYP2J2 expression is induced as a result of PPARα stimulation, resulting in a neuroprotective effect.


Assuntos
Berberina/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Glioma/metabolismo , Fármacos Neuroprotetores/farmacologia , PPAR alfa/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citocromo P-450 CYP2J2 , Sistema Enzimático do Citocromo P-450/genética , Glioma/enzimologia , Glioma/genética , Humanos , PPAR alfa/agonistas , PPAR alfa/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos
5.
Genome Res ; 26(10): 1376-1387, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27470111

RESUMO

The rates at which lesions are removed by DNA repair can vary widely throughout the genome, with important implications for genomic stability. To study this, we measured the distribution of nucleotide excision repair (NER) rates for UV-induced lesions throughout the budding yeast genome. By plotting these repair rates in relation to genes and their associated flanking sequences, we reveal that, in normal cells, genomic repair rates display a distinctive pattern, suggesting that DNA repair is highly organized within the genome. Furthermore, by comparing genome-wide DNA repair rates in wild-type cells and cells defective in the global genome-NER (GG-NER) subpathway, we establish how this alters the distribution of NER rates throughout the genome. We also examined the genomic locations of GG-NER factor binding to chromatin before and after UV irradiation, revealing that GG-NER is organized and initiated from specific genomic locations. At these sites, chromatin occupancy of the histone acetyl-transferase Gcn5 is controlled by the GG-NER complex, which regulates histone H3 acetylation and chromatin structure, thereby promoting efficient DNA repair of UV-induced lesions. Chromatin remodeling during the GG-NER process is therefore organized into these genomic domains. Importantly, loss of Gcn5 significantly alters the genomic distribution of NER rates; this has implications for the effects of chromatin modifiers on the distribution of mutations that arise throughout the genome.


Assuntos
Cromatina/genética , Reparo do DNA , Genoma Fúngico , Acetilação , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Taxa de Mutação , Processamento de Proteína Pós-Traducional , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
6.
Pharmazie ; 73(4): 223-247, 2018 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-29609690

RESUMO

Limited studies have investigated the antiviral efficacy of entecavir (ETV)-based rescue therapy in lamivudine (LAM)-resistant chronic hepatitis B (CHB) patients. We retrospectively analyzed the efficacy of entecavir (ETV) monotherapy versus ETV-tenofovir disoproxil fumarate (TDF) combination therapy in 220 LAM-resistant CHB patients. Among 220 patients, 114 patients were treated with ETV monotherapy and 106 were treated with ETV-TDF combination therapy for at least 24 months. There were no significant differences between the two groups in baseline characteristics. During the follow-up of 24 months, virologic response (VR) occurred in 146 (66.4%) patients (58 patients belonged to the ETV monotherapy group and 88 patients belonged to the ETV-TDF combination group). The VR rates were different between the ETV and ETV-TDF groups (32.5% vs. 57.5% at 6 months, 50.0% vs. 77.4% at 12 months; and 50.9% vs. 83.0% at 24 months, P<0.001). In addition, both groups showed no difference in terms of the biochemical and HBeAg response. The rates of viral breakthrough at 6, 12 and 24 months were significantly different between ETV and ETV-TDF groups (2.63%, 4.39% and 9.65% vs. 0.00%, 0.94% and 1.89% at 6, 12 and 24 months, respectively). The ETV-TDF group was superior to the ETV group in achieving a virologic response. Moreover, the ETV-TDF was lower than the ETV group in achieving the initial viral breakthrough and genotypic mutations. Therefore, ETV-TDF combination therapy might be a better regimen than ETV monotherapy in the subgroup of LAM-resistant Chinese patients with CHB.


Assuntos
Antivirais/uso terapêutico , Guanina/análogos & derivados , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Adulto , China , DNA Viral/sangue , Farmacorresistência Viral , Quimioterapia Combinada , Feminino , Genótipo , Guanina/uso terapêutico , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
7.
Nucleic Acids Res ; 43(15): 7360-70, 2015 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-26150418

RESUMO

Regulating gene expression programmes is a central facet of the DNA damage response. The Dun1 kinase protein controls expression of many DNA damage induced genes, including the ribonucleotide reductase genes, which regulate cellular dNTP pools. Using a combination of gene expression profiling and chromatin immunoprecipitation, we demonstrate that in the absence of DNA damage the yeast Rad4-Rad23 nucleotide excision repair complex binds to the promoters of certain DNA damage response genes including DUN1, inhibiting their expression. UV radiation promotes the loss of occupancy of the Rad4-Rad23 complex from the regulatory regions of these genes, enabling their induction and thereby controlling the production of dNTPs. We demonstrate that this regulatory mechanism, which is dependent on the ubiquitination of Rad4 by the GG-NER E3 ligase, promotes UV survival in yeast cells. These results support an unanticipated regulatory mechanism that integrates ubiquitination of NER DNA repair factors with the regulation of the transcriptional response controlling dNTP production and cellular survival after UV damage.


Assuntos
Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Desoxirribonucleotídeos/metabolismo , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Ubiquitinação , Raios Ultravioleta , Dano ao DNA , Regiões Promotoras Genéticas , Transcrição Gênica , Ubiquitina-Proteína Ligases/metabolismo , Leveduras/enzimologia , Leveduras/genética , Leveduras/metabolismo , Leveduras/efeitos da radiação
8.
Nanotechnology ; 26(45): 455302, 2015 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-26472271

RESUMO

Exploitation of facile and versatile synthetic approaches to polymeric nanoarchitectures is of great interest in polymer science and engineering. Herein, we show that a simple hydrothermal route using double-solvents as reaction media has the ability to generate polymer nanospheres with tunable morphologies and components. In this one-pot approach, condensation polymerization of a resol precursor and radical polymerization of styrene are allowed to occur simultaneously under hydrothermal treatment. The synergistic self-organization of phenol-formaldehyde crosslinked networks and polystyrene chains leads to the formation of well-defined hollow nanospheres with adjustable shell thickness or even Janus particles comprising a solid hemisphere and a hollow hemisphere. Furthermore, control over the composition of the hollow polymer nanospheres can be easily achieved by introducing a third monomer into the hydrothermal system.

9.
Nanotechnology ; 26(2): 025103, 2015 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-25526236

RESUMO

Polymer assemblies with good biocompatibility, stimuli-responsive properties and clinical imaging capability are desirable carriers for future biomedical applications. Herein, we report on the synthesis of a novel anthracenecarboxaldehyde-decorated poly(N-(4-aminophenyl) methacryl amide-oligoethyleneglycolmonomethylether methacrylate) (P(MAAPAC-MAAP-MAPEG)) copolymer, comprising fluorescent chromophore and acid-labile moiety. This copolymer can assemble into micelles in aqueous solution and shows a spherical shape with well-defined particle size and narrow particle size distribution. The pH-responsive property of the micelles has been evaluated by the change of particle size and the controlled release of guest molecules. The intrinsic fluorescence property endows the micelles with excellent cell/tissue imaging capability. Cell viability evaluation with human hepatocellular carcinoma BEL-7402 cells demonstrates that the micelles are nontoxic. The cellular uptake of the micelles indicates a time-dependent behavior. The H22-tumor bearing mice treated with the micelles clearly exhibits the tumor accumulation. These multi-functional nanocarriers may be of great interest in the application of drug delivery.


Assuntos
Preparações de Ação Retardada , Imagem Molecular/métodos , Polímeros/química , Animais , Morte Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Endocitose , Feminino , Humanos , Concentração de Íons de Hidrogênio , Camundongos Endogâmicos BALB C , Camundongos Nus , Micelas , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Polímeros/síntese química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
10.
PLoS Genet ; 7(6): e1002124, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21698136

RESUMO

Global genome nucleotide excision repair removes DNA damage from transcriptionally silent regions of the genome. Relatively little is known about the molecular events that initiate and regulate this process in the context of chromatin. We've shown that, in response to UV radiation-induced DNA damage, increased histone H3 acetylation at lysine 9 and 14 correlates with changes in chromatin structure, and these alterations are associated with efficient global genome nucleotide excision repair in yeast. These changes depend on the presence of the Rad16 protein. Remarkably, constitutive hyperacetylation of histone H3 can suppress the requirement for Rad7 and Rad16, two components of a global genome repair complex, during repair. This reveals the connection between histone H3 acetylation and DNA repair. Here, we investigate how chromatin structure is modified following UV irradiation to facilitate DNA repair in yeast. Using a combination of chromatin immunoprecipitation to measure histone acetylation levels, histone acetylase occupancy in chromatin, MNase digestion, or restriction enzyme endonuclease accessibility assays to analyse chromatin structure, and finally nucleotide excision repair assays to examine DNA repair, we demonstrate that global genome nucleotide excision repair drives UV-induced chromatin remodelling by controlling histone H3 acetylation levels in chromatin. The concerted action of the ATPase and C3HC4 RING domains of Rad16 combine to regulate the occupancy of the histone acetyl transferase Gcn5 on chromatin in response to UV damage. We conclude that the global genome repair complex in yeast regulates UV-induced histone H3 acetylation by controlling the accessibility of the histone acetyl transferase Gcn5 in chromatin. The resultant changes in histone H3 acetylation promote chromatin remodelling necessary for efficient repair of DNA damage. Recent evidence suggests that GCN5 plays a role in NER in human cells. Our work provides important insight into how GG-NER operates in chromatin.


Assuntos
Montagem e Desmontagem da Cromatina/genética , Dano ao DNA , Reparo do DNA/genética , Saccharomyces cerevisiae , Acetilação/efeitos da radiação , Adenosina Trifosfatases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Deleção de Genes , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Lipoproteínas/genética , Proteínas Nucleares/genética , Feromônios/genética , Regiões Promotoras Genéticas/genética , Estrutura Terciária de Proteína , Proteínas Repressoras/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/efeitos da radiação , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Raios Ultravioleta
11.
Foods ; 12(19)2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37835349

RESUMO

The exceptional biocompatibility of emulsion systems that rely on stabilizing protein-polysaccharide particles presents extensive possibilities for the transportation of bioactive carriers, making them highly promising for various biological applications. The current work aimed to explore the phenomenon of complex coacervation between sesame protein isolate (SPI) and four distinct polysaccharides, namely, Arabic gum (GA), carrageenan (CAR), sodium carboxymethyl cellulose (CMC), and sodium alginate (SA). The study objective was achieved by fabricating emulsions through the blending of these polymers with oil at their maximum turbidity level (φ = 0.6), followed by the measurement of their rheological properties. The turbidity, ζ-potential, and particle size were among the techno-parameters analyzed to assess the emulsion stability. The microstructural characterization of the emulsions was conducted using both transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Furthermore, the functional properties were examined using Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The SPI incorporated with SA, CMC, and CAR reached the maximum turbidity (0.2% w/v) at a ratio of 4:1, corresponding to the pH values of 4.5, 3, or 3.5, respectively. The SPI-GA mixture exhibited the maximum turbidity at a ratio of 10:1 and pH 4.5. Results from the FTIR and XRD analyses provided evidence of complex formation between SPI and the four polysaccharides, with the electrostatic and hydrogen bond interactions facilitating the binding of SPI to these polysaccharides. SPI was bound to the four polysaccharides through electrostatic and hydrogen bond interactions. The SPI-CMC and SPI-SA emulsions were more stable after two weeks of storage.

12.
J Invest Dermatol ; 143(1): 67-77.e15, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35933036

RESUMO

Although chronic spontaneous urticaria (CSU) is a common disease, GWASs of CSU are lacking. We aimed to identify susceptibility SNPs by performing a GWAS in Chinese Han adults with CSU. The discovery cohort included 430 CSU cases and 482 healthy controls. The GWAS findings were validated in 800 CSU cases and 900 healthy controls. Genetic, functional enrichment, and bioinformatic analyses of genome-wide significant SNPs were performed to assess the association between CSU and autoimmunity or atopy. Five genome-wide significant SNPs were identified: rs434124/LILRA3, rs61986182/IGHG1/2, rs73075571/TDGF1, rs9378141/HLA-G, and rs3789612/PTPN22. The first four SNPs were in linkage disequilibrium with autoimmune-related diseases‒associated SNPs and were cis-expression quantitative trait loci in immune cells. The five SNPs-annotated genes were significantly enriched in immune processes. Higher polygenic risk scores and allele frequencies of rs3789612∗T, rs9378141∗C, and rs73075571∗G were significantly associated with autoimmune-related CSU phenotypes, including positive antithyroglobulin IgG, positive anti-FcεRIα IgG, total IgE <40 IU/ml, and positive antithyroid peroxidase IgG but not with atopic or allergic sensitized CSU phenotypes. This GWAS of CSU identifies five risk loci and reveals that CSU shares genetic overlap with autoimmune diseases and that genetic factors predisposing to CSU mainly manifest through associations with autoimmune traits.


Assuntos
Doenças Autoimunes , Urticária Crônica , Urticária , Humanos , Estudo de Associação Genômica Ampla , Urticária/genética , Doença Crônica , Urticária Crônica/genética , Doenças Autoimunes/genética , Imunoglobulina G , Proteína Tirosina Fosfatase não Receptora Tipo 22 , Receptores Imunológicos
13.
Nat Biotechnol ; 41(10): 1457-1464, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36747096

RESUMO

DNA comprises molecular information stored in genetic and epigenetic bases, both of which are vital to our understanding of biology. Most DNA sequencing approaches address either genetics or epigenetics and thus capture incomplete information. Methods widely used to detect epigenetic DNA bases fail to capture common C-to-T mutations or distinguish 5-methylcytosine from 5-hydroxymethylcytosine. We present a single base-resolution sequencing methodology that sequences complete genetics and the two most common cytosine modifications in a single workflow. DNA is copied and bases are enzymatically converted. Coupled decoding of bases across the original and copy strand provides a phased digital readout. Methods are demonstrated on human genomic DNA and cell-free DNA from a blood sample of a patient with cancer. The approach is accurate, requires low DNA input and has a simple workflow and analysis pipeline. Simultaneous, phased reading of genetic and epigenetic bases provides a more complete picture of the information stored in genomes and has applications throughout biomedicine.

14.
Int J Mol Sci ; 13(9): 11141-11164, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23109843

RESUMO

Here we review our development of, and results with, high resolution studies on global genome nucleotide excision repair (GGNER) in Saccharomyces cerevisiae. We have focused on how GGNER relates to histone acetylation for its functioning and we have identified the histone acetyl tranferase Gcn5 and acetylation at lysines 9/14 of histone H3 as a major factor in enabling efficient repair. We consider results employing primarily MFA2 as a model gene, but also those with URA3 located at subtelomeric sequences. In the latter case we also see a role for acetylation at histone H4. We then go on to outline the development of a high resolution genome-wide approach that enables one to examine correlations between histone modifications and the nucleotide excision repair (NER) of UV-induced cyclobutane pyrimidine dimers throughout entire genomes. This is an approach that will enable rapid advances in understanding the complexities of how compacted chromatin in chromosomes is processed to access DNA damage and then returned to its pre-damaged status to maintain epigenetic codes.


Assuntos
Cromatina/genética , Dano ao DNA/genética , Reparo do DNA/genética , Saccharomyces cerevisiae/genética , Acetilação , Proteínas de Ligação a DNA/metabolismo , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Lipoproteínas/genética , Feromônios/genética , Dímeros de Pirimidina/química , Dímeros de Pirimidina/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
15.
Front Genet ; 13: 937623, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36147491

RESUMO

Cutaneous T-cell lymphomas (CTCLs) are a kind of non-Hodgkin lymphoma that originates from skin, which is difficult to treat with traditional drugs. Human histone deacetylase inhibitors (HDACi) targeted therapy has become a promising treatment strategy in recent years, but some patients can develop resistance to the drug, leading to treatment failure. There are no public reports on whether alternative splicing (AS) and RNA binding proteins (RBP) affect the efficacy of targeted therapy. Using data from the Gene Expression Omnibus (GEO) database, we established a co-change network of AS events and RBP in CTCLs for the first time, and analyzed the potential regulatory effects of RBP on HDACi-related AS events. The dataset GSE132053, which contained the RNA sequence data for 17 HDACi samples, was downloaded and clean reads were aligned to the human GRCh38 genome by hierarchical indexing for spliced alignment of the transcripts, allowing four mismatches. Gene expression levels were evaluated using exons per million fragments mapped for each gene. Student's t-tests were performed to evaluate the significance of changes in ratios for AS events, and regulated alternative splicing events (RASEs) were defined as events with p values less than 0.05. To sort the differentially expressed genes functional categories, Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways were identified using the KOBAS 2.0 server. The regulatory mechanisms of the RASEs and RBPs were evaluated using Pearson's correlation coefficient. Seven indirect events of HDACi resistance or sensitivity were identified: NIR_5151_RP11-977G19.10, NIR_4557_IRAG2, NIR_11870_SUMO1, NIR_5347_ING4, NIR_17935_DNAJC2, NIR_17974_CBLL1, and NIR_422_SLC50A1. The potential regulatory relationships between RBPs and HDACi-sensitive RASEs were also analyzed. LEPR and HNRNPAO significantly affected NIR_11870_SUMO1, suggesting a potential regulatory relationship. Additionally, CNN1 may regulate NIR_5347_ING4, CNOT3 may regulate NIR_17935_DNAJC2, and DQX1 and LENG9 may regulate NIR_422_SLC5A1. Overall, our findings establish a theoretical foundation for the precise targeted treatment of CTCLs with HDACi.

16.
Allergy Asthma Immunol Res ; 14(1): 131-142, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34983113

RESUMO

Immunoglobulin (Ig) E and IgG anti-thyroid autoantibodies (AAbs) play important roles in the immunopathogenesis of chronic spontaneous urticaria (CSU). To date, association of IgE and IgG AAbs with Chinese CSU patients has not been fully investigated. We aimed to explore prevalence rates of IgE and IgG AAbs in Chinese CSU patients and their association with clinical and laboratory parameters. Serum IgE and IgG AAbs against thyroid peroxidase (TPO) and thyroglobulin (TG), total IgE (tIgE) and specific IgEs were measured using enzyme-linked immunosorbent assay, chemiluminescence microparticle immunoassay and immunoblotting. Meta-analyses and literature review were conducted. The meta-analyses indicated that CSU cases were 4.98, 6.90 and 6.68 times more likely to have positive anti-TPO IgE, anti-TPO IgG and anti-TG IgG (all P < 0.001) compared with controls, respectively, and revealed a positive correlation between the prevalence rates of anti-TPO IgE and anti-TPO IgG (r = 0.53, P = 0.025). A total of 1,100 Chinese Han adult CSU patients and 1,100 ethnicity-, age- and sex-matched healthy controls were recruited from 15 centers. Prevalence rates of anti-TPO IgE, anti-TPO IgG, anti-TG IgE or anti-TG IgG in the patients were all significantly higher than those in the controls. Significant correlations were observed between prevalence rates of anti-TPO IgE and anti-TPO IgG (r = 0.297, P < 0.001) as well as between those of anti-TG IgE and anti-TG IgG in the patients (r = 0.137, P < 0.001). Patients with anti-TPO IgE or anti-TPO IgG had significantly lower tIgE levels (P < 0.001). Positive anti-TPO IgE, positive anti-TPO IgG and tIgE < 40 IU/mL were independent predictors of antihistamine-refractory cases. In conclusion, the prevalence rates of IgE and IgG AAbs in Chinese CSU patients are significantly elevated and reciprocally correlated. This study verifies the results of previous case-control studies of CSU patients from other populations and ethnicities.

17.
Sci Rep ; 12(1): 16566, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36195648

RESUMO

Early detection of cancer will improve survival rates. The blood biomarker 5-hydroxymethylcytosine has been shown to discriminate cancer. In a large covariate-controlled study of over two thousand individual blood samples, we created, tested and explored the properties of a 5-hydroxymethylcytosine-based classifier to detect colorectal cancer (CRC). In an independent validation sample set, the classifier discriminated CRC samples from controls with an area under the receiver operating characteristic curve (AUC) of 90% (95% CI [87, 93]). Sensitivity was 55% at 95% specificity. Performance was similar for early stage 1 (AUC 89%; 95% CI [83, 94]) and late stage 4 CRC (AUC 94%; 95% CI [89, 98]). The classifier could detect CRC even when the proportion of tumor DNA in blood was undetectable by other methods. Expanding the classifier to include information about cell-free DNA fragment size and abundance across the genome led to gains in sensitivity (63% at 95% specificity), with similar overall performance (AUC 91%; 95% CI [89, 94]). We confirm that 5-hydroxymethylcytosine can be used to detect CRC, even in early-stage disease. Therefore, the inclusion of 5-hydroxymethylcytosine in multianalyte testing could improve sensitivity for the detection of early-stage cancer.


Assuntos
Ácidos Nucleicos Livres , Neoplasias Colorretais , Biomarcadores Tumorais/genética , Ácidos Nucleicos Livres/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , DNA/genética , Detecção Precoce de Câncer/métodos , Humanos , Sensibilidade e Especificidade
18.
World J Clin Cases ; 9(34): 10430-10437, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-35004975

RESUMO

Celiac disease (CD) is an autoimmune intestinal disease caused by the intake of gluten-containing cereals and their products by individuals with genetic susceptibility genes. Vitiligo is a commonly acquired depigmentation of the skin; its clinical manifestation are skin patches caused by localized or generalized melanin deficiency. Both diseases have similar global incidence rates (approximately 1%) and are associated to similar diseases, including autoimmune bullous disease, inflammatory bowel disease, autoimmune thyroiditis, autoimmune gastritis, and type 1 diabetes. The relationship between CD and vitiligo has been reported in several studies, but their conclusions are inconsistent. Further, it has also been reported that a gluten-free diet (GFD) can improve the symptoms of immune-related skin diseases such as vitiligo. In this mini-review, we summarize and review the literature on the relationship between CD and vitiligo, assess the therapeutic significance of GFD for patients with vitiligo, and explore their possible physiopathology. We are hopeful that the information summarized here will assist physicians who treat patients with CD or vitiligo, thereby improving the prognosis.

19.
Front Genet ; 12: 627092, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679890

RESUMO

Vitiligo is a common immune-related depigmentation condition, and its pathogenesis remains unclear. This study used a combination of bioinformatics methods and expression analysis techniques to explore the relationship between immune cell infiltration and gene expression in vitiligo. Previously reported gene expression microarray data from the skin (GSE53146 and GSE75819) and peripheral blood (GSE80009 and GSE90880) of vitiligo patients and healthy controls was used in the analysis. R software was used to filter the differentially expressed genes (DEGs) in each dataset, and the KOBAS 2.0 server was used to perform functional enrichment analysis. Compared with healthy controls, the upregulated genes in skin lesions and peripheral blood leukocytes of vitiligo patents were highly enriched in immune response pathways and inflammatory response signaling pathways. Immunedeconv software and the EPIC method were used to analyze the expression levels of marker genes to obtain the immune cell population in the samples. In the lesional skin of vitiligo patients, the proportions of macrophages, B cells and NK cells were increased compared with healthy controls. In the peripheral blood of vitiligo patients, CD8+ T cells and macrophages were significantly increased. A coexpression analysis of the cell populations and DEGs showed that differentially expressed immune and inflammation response genes had a strong positive correlation with macrophages. The TLR4 receptor pathway, interferon gamma-mediated signaling pathway and lipopolysaccharide-related pathway were positively correlated with CD4+ T cells. Regarding immune response-related genes, the overexpression of IFITM2, TNFSF10, GZMA, ADAMDEC1, NCF2, ADAR, SIGLEC16, and WIPF2 were related to macrophage abundance, while the overexpression of ICOS, GPR183, RGS1, ILF2 and CD28 were related to CD4+ T cell abundance. GZMA and CXCL10 expression were associated with CD8+ T cell abundance. Regarding inflammatory response-related genes, the overexpression of CEBPB, ADAM8, CXCR3, and TNIP3 promoted macrophage infiltration. Only ADORA1 expression was associated with CD4+ T cell infiltration. ADAM8 and CXCL10 expression were associated with CD8+ T cell abundance. The overexpression of CCL18, CXCL10, FOS, NLRC4, LY96, HCK, MYD88, and KLRG1, which are related to inflammation and immune responses, were associated with macrophage abundance. We also found that immune cells infiltration in vitiligo was associated with antigen presentation-related genes expression. The genes and pathways identified in this study may point to new directions for vitiligo treatment.

20.
DNA Repair (Amst) ; 8(2): 146-52, 2009 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19041427

RESUMO

A typical view of how DNA repair functions in chromatin usually depicts a struggle in which the DNA repair machinery battles to overcome the inhibitory effect of chromatin on the repair process. It may be that in this current interpretation the repair mechanisms are 'tilting at windmills', fighting an imaginary foe. An emerging picture suggests that we should not consider chromatin as an inhibitory force to be overcome like some quixotic giant by the DNA repair processes. Instead we should now recognize that DNA repair and chromatin metabolism are inextricably and mechanistically linked. Here we discuss the latest findings which are beginning to reveal how changes in chromatin dynamics integrate with the DNA repair process in response to UV induced DNA damage, with an emphasis on events in the yeast Saccharomyces cerevisiae.


Assuntos
Cromossomos/metabolismo , Reparo do DNA , DNA/metabolismo , Animais , Cromatina/metabolismo , Dano ao DNA , Genoma/genética , Humanos
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