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1.
Sci Total Environ ; 904: 166811, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37673249

RESUMO

A novel wastewater treatment plant process was constructed to overcome the challenge of simultaneous nitrate removal and phosphorus (P) recovery. The results revealed that the P and nitrate removal efficiency rose from 39.0 % and 48.4 % to 92.8 % and 93.6 % after 136 days of operation, and the total P content in the biofilm (TPbiofilm) rose from 15.8 mg/g SS to 57.8 mg/g SS. Moreover, the increase of TPbiofilm changed the metabolic mode of denitrifying polyphosphate accumulating organisms (DPAOs), increasing the P concentration of the enriched stream to 172.5 mg/L. Furthermore, the acid/alkaline fermentation led to the rupture of the cell membrane, which released poly-phosphate and ortho-phosphate of cell/EPS in DPAOs and released metal­phosphorus (CaP and MgP). In addition, high-throughput sequencing analysis demonstrated that the relative abundance of DPAOs involved in P storage increased, wherein the abundance of Acinetobacter and Saprospiraceae rose from 8.0 % and 4.1 % to 16.1 % and 14.0 %. What's more, the highest P recovery efficiency (98.3 ± 1.1 %) could be obtained at optimal conditions for struvite precipitation (pH = 7.56 and P: N: Mg = 1.87:3.66:1) through the response surface method (RSM) simulation, and the precipitates test analysis indicated that P recovery from biofilm sludge was potentially operable. This research was of great essentiality for exploring the recovery of P from biofilm sludge.


Assuntos
Fósforo , Esgotos , Fósforo/metabolismo , Nitratos/metabolismo , Desnitrificação , Anaerobiose , Reatores Biológicos , Polifosfatos , Biofilmes , Eliminação de Resíduos Líquidos/métodos , Nitrogênio
2.
Plant Cell Environ ; 46(7): 2078-2096, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37128741

RESUMO

Gladiolus hybridus is one of the most popular flowers worldwide. However, its corm dormancy characteristic largely limits its off-season production. Long-term cold treatment (LT), which increases sugar content and reduces abscisic acid (ABA), is an efficient approach to accelerate corm dormancy release (CDR). Here, we identified a GhbZIP30-GhCCCH17 module that mediates the antagonism between sugars and ABA during CDR. We showed that sugars promoted CDR by reducing ABA levels in Gladiolus. Our data demonstrated that GhbZIP30 transcription factor directly binds the GhCCCH17 zinc finger promoter and activates its transcription, confirmed by yeast one-hybrid, dual-luciferase (Dual-LUC), chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) and electrophoretic mobility shift assay (EMSA). GhCCCH17 is a transcriptional activator, and its nuclear localisation is altered by surcose and cytokinin treatments. Both GhbZIP30 and GhCCCH17 positively respond to LT, sugars, and cytokinin treatments. Silencing GhbZIP30 or GhCCCH17 resulted in delayed CDR by regulating ABA metabolic genes, while their overexpression promoted CDR. Taken together, we propose that the GhbZIP30-GhCCCH17 module is involved in cold- and glucose-induced CDR by regulating ABA metabolic genes.


Assuntos
Ácido Abscísico , Dormência de Plantas , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Dormência de Plantas/genética , Fatores de Transcrição/metabolismo , Citocininas , Açúcares , Regulação da Expressão Gênica de Plantas
3.
Cancer Nurs ; 46(2): E91-E98, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35728010

RESUMO

BACKGROUND: Sleep disturbance is one of the symptoms with high incidence and negative influence in patients with cancer. A better understanding of the biological factors associated with sleep disturbance is critical to predict, treat, and manage this condition. OBJECTIVE: The aim of this study was to determine the correlation between sleep disturbance and proinflammatory markers in adult patients with cancer. METHODS: A systematic search was conducted in 7 databases from inception to March 1, 2020, for this meta-analysis. Two reviewers independently screened the studies, extracted data, and appraised the quality of the studies. Meta-analyses were conducted using Stata 12.0 software. RESULTS: Sixteen studies were included. Results indicated that sleep disturbance was associated with higher levels of the overall proinflammatory markers and that the effect size was small yet significant. Further subgroup analyses suggested that sleep disturbance was significantly associated with interleukin-6 and C-reactive protein, but not with interleukin-1ß or tumor necrosis factor-α. Meta-regression results indicated that only the sample source affected the association between sleep disturbance and proinflammatory markers. CONCLUSION: There was a positive relationship between sleep disturbance and selected proinflammatory markers in adult patients with cancer. IMPLICATION FOR PRACTICE: This review provides empirical support for the association between sleep disturbance and certain proinflammatory markers. Healthcare providers can further explore specific biomarkers to precisely identify the individuals at risk of sleep disturbance and develop targeted strategies for therapeutic and clinical interventions.


Assuntos
Neoplasias , Transtornos do Sono-Vigília , Adulto , Humanos , Transtornos do Sono-Vigília/epidemiologia , Neoplasias/complicações , Biomarcadores , Sono
4.
Clin Exp Metastasis ; 40(1): 5-32, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36318440

RESUMO

Portal vein tumor thrombosis (PVTT), a common complication of advanced hepatocellular carcinoma (HCC), remains the bottleneck of the treatments. Liver cancer cells potentially experienced multi-steps during PVTT process, including cancer cells leave from cancer nest, migrate in extracellular matrix, invade the vascular barrier, and colonize in the portal vein. Accumulated evidences have revealed numerous of molecular mechanisms including genetic and epigenetic regulation, cancer stem cells, immunosuppressive microenvironment, hypoxia, et al. contributed to the PVTT formation. In this review, we discuss state-of-the-art PVTT research on the potential molecular mechanisms and experimental models. In addition, we summarize PVTT-associated clinical trials and current treatments for PVTT and suppose perspectives exploring the molecular mechanisms and improving PVTT-related treatment for the future.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Trombose Venosa , Humanos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/tratamento farmacológico , Veia Porta/patologia , Epigênese Genética , Trombose Venosa/terapia , Trombose Venosa/complicações , Resultado do Tratamento , Estudos Retrospectivos , Microambiente Tumoral
5.
Acta Trop ; 232: 106483, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35469749

RESUMO

The plerocercoid larvae of the tapeworm Spirometra erinaceieuropaei can parasitize humans and animals and cause serious parasitic zoonosis. However, our knowledge of the developmental process of S. erinaceieuropaei is still inadequate. To better characterize differential and specific genes and pathways associated with parasite development, a comparative transcriptomic analysis of the plerocercoid stage and the adult stage was performed using RNA-seq and de novo analysis. Approximately 13,659 differentially expressed genes (DEGs) were identified in plerocercoids versus adults, of which 6455 DEGs were upregulated and 7204 were downregulated. DEGs involved in parasite immunoevasion were more active in plerocercoid larvae than in adults, while DEGs associated with metabolic activity were upregulated in adults. Gene Ontology (GO) and Kyoto Encyclopedia of Genes (KEGG) analyses revealed that most DEGs involved in protein phosphorylation/dephosphorylation and the Wnt signalling pathway were much more active in plerocercoid larvae. The molecular functions of upregulated unigenes in adults were mainly enriched for metabolic activities. qPCR validated that the expression levels of 10 selected DEGs were consistent with those in RNA-seq, confirming the accuracy of the RNA-seq results. Our results contributed to increasing the knowledge on the S. erinaceieuropaei gene repertoire and expression profile and also provide valuable resources for functional studies on the molecular mechanisms of S. erinaceieuropaei.


Assuntos
Infecções por Cestoides , Esparganose , Spirometra , Animais , Perfilação da Expressão Gênica , Esparganose/parasitologia , Spirometra/genética , Transcriptoma , Zoonoses
6.
Chromosome Res ; 30(1): 109-121, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35142952

RESUMO

DNA methylation of CpG dinucleotides is an important epigenetic modification involved in the regulation of mammalian gene expression, with each type of cell developing a specific methylation profile during its differentiation. Recently, it has been shown that a small subgroup of transcription factors (TFs) might promote DNA demethylation at their binding sites. We developed a bioinformatics pipeline to predict from genome-wide DNA methylation data TFs that promote DNA demethylation at their binding site. We applied the pipeline to International Human Epigenome Consortium methylome data and selected 393 candidate transcription factor binding motifs and associated 383 TFs that are likely associated with DNA demethylation. Validation of a subset of the candidate TFs using an in vitro assay suggested that 28 of 49 TFs from various TF families had DNA-demethylation-promoting activity; TF families, such as bHLH and ETS, contained both TFs with and without the activity. The identified TFs showed large demethylated/methylated CpG ratios and their demethylated CpGs showed significant bias toward hypermethylation in original cells. Furthermore, the identified TFs promoted demethylation of distinct sets of CpGs, with slight overlap of the targeted CpGs among TF family members, which was consistent with the results of a gene ontology (GO) term analysis of the identified TFs. Gene expression analysis of the identified TFs revealed that multiple TFs from various families are specifically expressed in human cells and tissues. Together, our results suggest that a large number of TFs from various TF families are associated with cell-type-specific DNA demethylation during human cellular development.


Assuntos
Desmetilação do DNA , Fatores de Transcrição , Animais , Sítios de Ligação , DNA/metabolismo , Metilação de DNA , Genoma , Humanos , Mamíferos/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Chem Commun (Camb) ; 58(15): 2508-2511, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35089297

RESUMO

We report herein a series of quinoline-4-carboxylic acid linked COFs via the multicomponent one-pot in situ Doebner reaction. The obtained acid-base bifunctional COFs are chemically stable and can highly promote one-pot cascade deacetalization-Knoevenagel condensation reaction in a heterogeneous way under solvent-free conditions.

8.
Heart Lung ; 51: 59-66, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34731699

RESUMO

BACKGROUND: Lung cancer stigma is a widespread psychosocial problem. We developed a short form of the Cataldo lung cancer stigma scale for Chinese people with lung cancer (CLCSS-C-SF) and compared its psychometric properties with those of the full and short versions. METHODS: This was a secondary analysis using data from the full CLCSS-C, distress thermometer and perceived social support of Chinese people with lung cancer (N = 394). Exploratory and confirmatory factor analysis (CFA) were used to identify factor structure and assess construct validity. The internal consistency and concurrent and known-group validity were evaluated. RESULTS: The 22-item CLCSS-C-SF comprised four factors. The convergent validity evaluated using average variance extracted and discriminant validity were acceptable. Cronbach's alphas, concurrent and known-group validity were satisfactory for three versions. Only the four-factor model proposed was validated by CFA. CONCLUSION: The CLCSS-C-SF is reliable and valid and can be used in Chinese lung cancer populations.


Assuntos
Neoplasias Pulmonares , Estigma Social , China , Humanos , Neoplasias Pulmonares/psicologia , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
9.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3497-3504, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676710

RESUMO

Taking Pinus tabuliformis plantations at different slopes in Songshan Mountains, Henan Province, China as subjects, we established different residual chronologies of P. tabuliformis in Paomaling (PML) and Junjifeng (JJF) and whole region (RC). The results showed that the chro-nological quality of PML was higher than that of JJF. Chronologies of PML and JJF had more climate information, which had significant positive relationship with mean temperature in current February, mean temperature and mean maximum temperature at the end of growing season (September-October), and significant negative relationship with mean maximum temperature in current May. The response of radial growth of P. tabuliformis to climate differed in PML and JJF. Radial growth of P. tabuliformis in PML was positively correlated with mean minimum temperature in March and precipitation in September, while that in JJF was positively correlated with precipitation in May and mean minimum temperature in September. Residual chronologies of P. tabuliformis in whole region contained more climate information. The multiple regression analysis method was used to simulate that the main limiting factors of tree-ring width growth of P. tabuliformis, which was a range of temperature indicators, especially current mean temperature in September. The result was consistent with that of correlation analysis. This study could provide basic services for forest protection and ecological construction in Songshan Mountains region.


Assuntos
Pinus , Árvores , China , Clima , Florestas
10.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3512-3520, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676712

RESUMO

Based on the method of tree-ring chronology, we established ring-width standard chrono-logies of Abies faxoniana and Sabina saltuaria in Liangtaigou, Lixian County, western Sichuan Province, and their regional composite chronology (RC) to study the responses of radial growth of those two coniferous species to climate change, which provided a basis for the protection and mana-gement of forest ecosystems in this region under the background of global warming. The results showed that the RC contained the common climatic information of two individual chronologies, which had higher signal-to-noise ratio and expressed population signal. The correlation analysis showed that three chronologies had a good consistency in the response to climate factors. All chronologies were significantly correlated with temperature, with S. saltuaria being more sensitive to temperature changes. Relative humidity had stronger limiting effect on both species than precipitation in May and October. After the abrupt warming in 1994, the correlation between ring-width chrono-logy of A. faxoniana and monthly mean temperature shifted obviously from negative to positive in some months, which indicated the radial growth of A. faxoniana showed unstable in response to temperature. However, the radial growth of both species showed different broadening trend and the sensitivity to temperature response was weakened.


Assuntos
Traqueófitas , China , Mudança Climática , Ecossistema , Florestas
11.
J Mol Model ; 27(10): 308, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34596789

RESUMO

Density functional theory (DFT) methods were employed to design a new family of wing-like and propeller-like multi-tetrazole molecules based on the combination of N-center multi-tetrazole and various energetic groups. The optimized geometry, electronic properties, and thermodynamics were calculated for investigating the molecular stability and chemical reactivity. Their energetic parameters including density, heats of formation, detonation properties, and impact sensitivity were extensively evaluated, and the effects of energetic groups were investigated as well. These newly designed wing-like and propeller-like multi-tetrazole molecules exhibit acceptable oxygen balance, moderate impact sensitivities, high density, excellent heats of formation, and good detonation performance. Especially, B3, B4, B5, and B6 are very helpful for enhancing their detonation performance (D ≥ 9500 m·s-1, P ≥ 41 GPa) are promising candidates for new environmentally friendly HEDMs.

12.
Parasit Vectors ; 14(1): 537, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34649597

RESUMO

BACKGROUND: Necator americanus is one of the major etiological agents of human ancylostomiasis. Historically, the epidemiology of ancylostomiasis in Henan Province of central China and the molecular characteristics of N. americanus have been poorly understood. METHODS: In this study, we report a case of ancylostomiasis in Zhengzhou city of Henan Province. We also review the epidemiology of ancylostomiasis in Henan Province from 1949 to 2020. In addition, the complete mitochondrial (mt) genome of one clinical isolate is fully characterized using Illumina sequencing. All available mt genomes of hookworms in GenBank were included to reconstruct the phylogeny using both maximum likelihood (ML) and Bayesian inference (BI) methods. RESULTS: A total of three worms were collected from the patient. These worms were identified as N. americanus based on morphological characteristics as well as confirmed by genotyping with the barcoding gene cox1. Although ancylostomiasis cases have dropped substantially in recent years, hookworm infection is still a public health problem in underdeveloped areas and remote rural areas in Henan Province. The mt genome features of the N. americanus contained 12 protein-coding genes (PCGs), 22 transfer RNA genes, two ribosomal RNA genes, and a major non-coding region. The nad1 gene showed high sequence variability among isolates, which is worth considering for future genetic studies of N. americanus. Phylogenetic analyses support the monophyly of hookworm isolates from different hosts and distinct geographical locations. CONCLUSIONS: The mt genome of N. americanus presented here will serve as a useful data set for studying population genetics and phylogenetic relationships of hookworms. Positive measures for preventing and controlling ancylostomiasis are required by both health services and individuals in Henan Province.


Assuntos
Ancilostomíase/epidemiologia , Genoma Helmíntico , Técnicas de Diagnóstico Molecular , Necator americanus/genética , Necatoríase/diagnóstico , Necatoríase/epidemiologia , Idoso , Animais , China/epidemiologia , DNA de Helmintos/genética , Feminino , Humanos , Necator americanus/isolamento & purificação
13.
Eur J Oncol Nurs ; 55: 102046, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34710809

RESUMO

PURPOSE: To describe the trajectory, number, and types of symptom clusters at three time points (i.e., day of admission [T1], 2-4 days postoperatively [T2], and 1 month postoperatively [T3]) using ratings of symptom occurrence and severity and to identify the changes in these symptom clusters over time in patients with lung cancer. METHODS: We analysed the data of 217 lung cancer patients who received surgical treatment at a tertiary hospital affiliated to Anhui Medical University, in Hefei City, China. The occurrence and severity of 19 symptoms at all points of measurement were measured using the general and lung cancer modules of the M.D. Anderson Symptom Inventory. Exploratory factor analysis was performed to extract the symptom clusters. RESULTS: Seven symptom clusters were identified across symptom dimensions. However, only three of them (i.e., lung cancer specific, sleep disturbance, and nervous system) were relatively stable across dimensions and time. Two symptom clusters varied over time but not with dimensions (nutritional and gastrointestinal). The other two symptom clusters (psychological and respiratory) differed in terms of time and dimensions. CONCLUSIONS: Findings may provide insights into the seven identified clusters and overall stability of three symptom clusters in lung cancer patients perioperatively.


Assuntos
Antineoplásicos , Neoplasias Pulmonares , Antineoplásicos/uso terapêutico , Humanos , Estudos Longitudinais , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/tratamento farmacológico , Índice de Gravidade de Doença , Síndrome
14.
Cancer Lett ; 522: 22-31, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517084

RESUMO

The relationship between immune and inflammatory responses in hepatocellular carcinoma (HCC) has garnered significant interest. In the peripheral blood and tumour microenvironment (TME), neutrophils, which are innate immune cells, crucially respond to various inflammatory factors, leading to tumour progression. To some extent, they affect the clinical treatment strategy and survival among HCC patients. A high circulating neutrophil-to-lymphocyte ratio is a reliable factor that can be used to predict poor outcomes in HCC patients. However, the mechanisms underlying the protumoural effects of circulating neutrophils remain poorly understood. Besides, the distinct role and function of neutrophils at the site of HCC remain relatively unclear, which is partially attributed to their substantial heterogeneity compared with other immune cells. In this review, we firstly discuss the current information available, detailing distinct subsets, functional phenotypes, and the impact of circulating and tumour-infiltrating neutrophils on tumourigenesis in HCC. Furthermore, we describe recent pre-clinical and clinical studies concerning neutrophils for evaluating the feasibility of targeting diverse protumoural aspects to improve therapeutic efficacy, thus paving the way for neutrophil-based treatment, especially in combination with immunotherapy.


Assuntos
Carcinogênese/imunologia , Carcinoma Hepatocelular/imunologia , Neoplasias Hepáticas/imunologia , Neutrófilos/imunologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Humanos , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neutrófilos/patologia , Microambiente Tumoral/imunologia
15.
Anat Sci Int ; 96(1): 30-41, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32535854

RESUMO

Female urinary incontinence mainly relates to damage of female urethra supporting structures, while its anatomy and function specially in which the connective tissue part are still unclear and controversial. We study it based on 4 thin-sectional, high-resolution, transverse sectional anatomical images [Chinese Visible Human (CVH) images] and 10 high-resolution MRI images from volunteers. The female urethral supporting structures and its adjacent structures were segmented and three-dimensional (3D) reconstructed with Amira software. The urethral supporting structures include muscular and connective tissue supporting structures. Muscular supporting structures are composed of levator ani muslce and striated urethral sphincter, the connective tissue supporting structures are composed of anterior vaginal wall, pubovesical muscle, pubovesical ligament, lateral vesical ligament, and tendinous arch of pelvic fascia (TAPF). The anterior vaginal wall includes tight and loose connections between urethral, bladder, and vagina. The lateral vesical ligament connects the proximal part of the urethra to the TAPF. The pubovesical muscle is crescent shaped and continues with the detrusor of the bladder superior and directly connects the TAPF laterally. The TAPF is an obvious fibrous structure that originates at the middle-posterior surface of the pubis, travels onto the parietal pelvic fascia, and inserts posteriorly onto the ischial spine. The anterior vaginal wall, the pubovesical muscle, the lateral vesical ligament, and the TAPF create the "hammock" structure and supplement DeLancey's theory. Its support to the proximal urethra and neck of bladder is crucial to maintain stability and urinary continence during increased abdominal pressure.


Assuntos
Anatomia Transversal/métodos , Imageamento por Ressonância Magnética/métodos , Uretra/anatomia & histologia , Uretra/diagnóstico por imagem , Adulto , Fáscia/anatomia & histologia , Feminino , Humanos , Imageamento Tridimensional , Ligamentos/anatomia & histologia , Diafragma da Pelve/anatomia & histologia , Diafragma da Pelve/fisiologia , Prolapso de Órgão Pélvico/etiologia , Prolapso de Órgão Pélvico/patologia , Uretra/fisiologia , Bexiga Urinária/anatomia & histologia , Bexiga Urinária/fisiologia , Incontinência Urinária por Estresse/etiologia , Incontinência Urinária por Estresse/patologia , Vagina/anatomia & histologia
16.
J Zhejiang Univ Sci B ; 20(1): 32-38, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30614228

RESUMO

The rapid developments of science and technology in China over recent decades, particularly in biomedical research, have brought forward serious challenges regarding ethical governance. Recently, Jian-kui HE, a Chinese scientist, claimed to have "created" the first gene-edited babies, designed to be naturally immune to the human immunodeficiency virus (HIV). The news immediately triggered widespread criticism, denouncement, and debate over the scientific and ethical legitimacy of HE's genetic experiments. China's guidelines and regulations have banned germline genome editing on human embryos for clinical use because of scientific and ethical concerns, in accordance with the international consensus. HE's human experimentation has not only violated these Chinese regulations, but also breached other ethical and regulatory norms. These include questionable scientific value, unreasonable risk-benefit ratio, illegitimate ethics review, invalid informed consent, and regulatory misconduct. This series of ethical failings of HE and his team reveal the institutional failure of the current ethics governance system which largely depends on scientist's self-regulation. The incident highlights the need for urgent improvement of ethics governance at all levels, the enforcement of technical and ethical guidelines, and the establishment of laws relating to such bioethical issues.


Assuntos
Edição de Genes/ética , Sistemas CRISPR-Cas , China , Termos de Consentimento/ética , Ética Médica , Feminino , Edição de Genes/legislação & jurisprudência , Técnicas de Inativação de Genes/ética , Infecções por HIV/genética , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Experimentação Humana/ética , Experimentação Humana/legislação & jurisprudência , Humanos , Recém-Nascido , Gravidez , Má Conduta Profissional/ética , Receptores CCR5/deficiência , Receptores CCR5/genética
17.
Int J Biol Macromol ; 121: 1186-1193, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30342144

RESUMO

Ultrafiltration is a separation process for purifying and concentrating macromolecular solutions. Using Baiyu yam (Dioscorea opposita Thunb) as the raw material, single-factor experiments, Box-Behnken design (BBD) and response surface methodology (RSM) were employed to investigate the effects of the ultrafiltration pH, temperature and pressure on the extraction rate of Chinese yam polysaccharide (CYP). The constructed regression model is highly significant, and the optimal ultrafiltration-assisted extraction conditions were determined to be the following: pH 6.5, 20 °C and 0.03 MPa. Under these optimal conditions, a CYP extraction rate of 88.7% was achieved. After purification with anion exchange (DE-52) and size-exclusion (Sephadex G-100) columns, the monosaccharide composition of CYP was determined to be 50.8% glucose, 24.2% mannose and 11.8% galactose. Fourier transform infrared (FT-IR) spectroscopy characterization of CYP confirmed the characteristic absorption peaks of the polysaccharides. The microstructure of CYP exhibited characteristics typical of amorphous powders. CYP also exhibited antioxidant activities, including the scavenging of DPPH radicals, hydroxyl radicals and superoxide anion radicals. Moreover, CYP exhibited a relatively strong inhibitory effect on BGC-823 cell growth.


Assuntos
Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Dioscorea/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Ultrafiltração/métodos , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Radicais Livres/química , Humanos , Concentração de Íons de Hidrogênio , Monossacarídeos/análise , Polissacarídeos/química , Pressão
19.
BMC Mol Biol ; 18(1): 9, 2017 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-28376714

RESUMO

BACKGROUND: SPI1 is an essential transcription factor (TF) for the hematopoietic lineage, in which its expression is tightly controlled through a -17-kb upstream regulatory region and a promoter region. Both regulatory regions are demethylated during hematopoietic development, although how the change of DNA methylation status is performed is still unknown. RESULTS: We found that the ectopic overexpression of RUNX1 (another key TF in hematopoiesis) in HEK-293T cells induces almost complete DNA demethylation at the -17-kb upstream regulatory region and partial but significant DNA demethylation at the proximal promoter region. This DNA demethylation occurred in mitomycin-C-treated nonproliferating cells at both regulatory regions, suggesting active DNA demethylation. Furthermore, ectopic RUNX1 expression induced significant endogenous SPI1 expression, although its expression level was much lower than that of natively SPI1-expressing monocyte cells. CONCLUSIONS: These results suggest the novel role of RUNX1 as an inducer of DNA demethylation at the SPI1 regulatory regions, although the mechanism of RUNX1-induced DNA demethylation remains to be explored.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Metilação de DNA , Replicação do DNA , Proteínas Proto-Oncogênicas/genética , Transativadores/genética , Sequência de Bases , Linhagem Celular , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Regulação da Expressão Gênica , Humanos , Regiões Promotoras Genéticas , Regulação para Cima
20.
Sci Rep ; 6: 34104, 2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27659693

RESUMO

Telomerase is the enzyme involved in extending telomeric DNA. Control of telomerase activity by modulating its access to chromosome ends is one of the most important fundamental mechanisms. This study established an in vitro yeast telomerase reconstitution system that resembles telomere replication in vivo. In this system, a tailed-duplex DNA formed by telomeric DNA was employed to mimic the structure of telomeres. The core catalytic components of telomerase Est2/Tlc1 RNA were used as the telomeric DNA extension machinery. Using the reconstituted systems, this study found that binding of Cdc13 to telomeric DNA inhibited the access of telomerase to its substrate. The result was further confirmed by a single-molecule approach using the tethered-particle motion (TPM)-based telomerase assay. The findings also showed that the inhibitory effect can be relieved by telomerase-associated protein Est1, consistent with the role of Cdc13 and Est1 in regulating telomere extension in vivo. Significantly, this study found that the DNA binding property of Cdc13 was altered by Est1, providing the first mechanistic evidence of Est1 regulating the access of telomerase to its substrate. Thus, the roles of Cdc13 and Est1 in modulating telomerase activity were clearly defined using the in vitro reconstituted system.

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