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1.
Cell ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971151

RESUMO

Homologous recombination deficiency (HRD) is prevalent in cancer, sensitizing tumor cells to poly (ADP-ribose) polymerase (PARP) inhibition. However, the impact of HRD and related therapies on the tumor microenvironment (TME) remains elusive. Our study generates single-cell gene expression and T cell receptor profiles, along with validatory multimodal datasets from >100 high-grade serous ovarian cancer (HGSOC) samples, primarily from a phase II clinical trial (NCT04507841). Neoadjuvant monotherapy with the PARP inhibitor (PARPi) niraparib achieves impressive 62.5% and 73.6% response rates per RECIST v.1.1 and GCIG CA125, respectively. We identify effector regulatory T cells (eTregs) as key responders to HRD and neoadjuvant therapies, co-occurring with other tumor-reactive T cells, particularly terminally exhausted CD8+ T cells (Tex). TME-wide interferon signaling correlates with cancer cells upregulating MHC class II and co-inhibitory ligands, potentially driving Treg and Tex fates. Depleting eTregs in HRD mouse models, with or without PARP inhibition, significantly suppresses tumor growth without observable toxicities, underscoring the potential of eTreg-focused therapeutics for HGSOC and other HRD-related tumors.

2.
Sci Rep ; 13(1): 19885, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37963940

RESUMO

The dosage-dependent recruitment of RNA polymerase II (Pol II) at the promoters of genes related to neurodevelopment and stem cell maintenance is required for transcription by the fine-tuned expression of SET-domain-containing protein 5 (SETD5). Pol II O-GlcNAcylation by O-GlcNAc transferase (OGT) is critical for preinitiation complex formation and transcription cycling. SETD5 dysregulation has been linked to stem cell-like properties in some cancer types; however, the role of SETD5 in cancer cell stemness has not yet been determined. We here show that aberrant SETD5 overexpression induces stemness in colorectal cancer (CRC) cells. SETD5 overexpression causes the upregulation of PI3K-AKT pathway-related genes and cancer stem cell (CSC) markers such as CD133, Kruppel-like factor 4 (KLF4), and estrogen-related receptor beta (ESRRB), leading to the gain of stem cell-like phenotypes. Our findings also revealed a functional relationship between SETD5, OGT, and Pol II. OGT-catalyzed Pol II glycosylation depends on SETD5, and the SETD5-Pol II interaction weakens in OGT-depleted cells, suggesting a SETD5-OGT-Pol II interdependence. SETD5 deficiency reduces Pol II occupancy at PI3K-AKT pathway-related genes and CD133 promoters, suggesting a role for SETD5-mediated Pol II recruitment in gene regulation. Moreover, the SETD5 depletion nullified the SETD5-induced stemness of CRC cells and Pol II O-GlcNAcylation. These findings support the hypothesis that SETD5 mediates OGT-catalyzed O-GlcNAcylation of RNA Pol II, which is involved in cancer cell stemness gain via CSC marker gene upregulation.


Assuntos
Neoplasias Colorretais , RNA Polimerase II , Humanos , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Neoplasias Colorretais/genética , Catálise , Processamento de Proteína Pós-Traducional , Metiltransferases/metabolismo
3.
Biochem Pharmacol ; 217: 115838, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37778445

RESUMO

M2 type tumor-associated macrophages, an essential component of the tumor microenvironment (TME), have been proved to contribute to tumor metastasis. Dauricine (Dau) has recently received widespread attention due to its multiple targets and low price. However, the effect of Dau on macrophage polarization of TME remains unclear. In this study, we investigated the effect of Dau on prostate cancer (PCa) metastasis and specifically its correlation to macrophage polarization. Our results showed that Dau efficiently suppressed M2 polarization of macrophages induced by interleukin (IL) -4 and IL-13. Mechanistically, Dau inhibited the activity of PI3K/AKT signaling pathway, which subsequently suppressed macrophage differentiation to M2 type. Importantly, our study indicated that Dau decreased the release of chitinase 3-like protein 1 (CHI3L1) from M2 macrophages, which ultimately inhibited the M2 macrophage-mediated progression of PCa cells in vitro and in vivo. Taken together, our data demonstrated that Dau suppressed M2 polarization of macrophages via downregulation of the PI3K/AKT signaling pathway, in turn, preventing proliferation, epithelial-mesenchymal transition, migration, and invasion of PCa cells. Thus, this study reveals a previously unrecognized function of Dau in inhibition of PCa progression via intervention in M2 polarization of macrophages.


Assuntos
Neoplasias da Próstata , Proteínas Proto-Oncogênicas c-akt , Masculino , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Macrófagos , Neoplasias da Próstata/metabolismo , Microambiente Tumoral , Linhagem Celular Tumoral
4.
Exp Mol Pathol ; 125: 104755, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35278461

RESUMO

Several studies have demonstrated that B7-H4 is highly expressed in a variety of cancers and often affects tumor development. However, its role in cancer stemness and epithelial-to-mesenchymal transition (EMT) in non-small cell lung cancer (NSCLC) has not been reported. Here, we investigated the relationship between B7-H4 expression and cancer stemness and EMT by immunohistochemistry in 106 NSCLC tissues obtained from patients. The results confirmed that B7-H4 is highly expressed in NSCLC tissues and closely correlated with the expression of EMT-related proteins (Snail, Vimentin) and cancer stemness-related proteins (SOX2, SOX9, and CD44). Immunofluorescence assay indicated that B7-H4 colocalized with SOX2 and SOX9 in the nuclei of NSCLC cells. Additionally, upon knocking down B7-H4, the expression of SOX2, SOX9, and CD44, as well as of Snail and Vimentin was inhibited, whereas E-cadherin expression was enhanced in NSCLC cells. Meanwhile, inhibiting the expression of B7-H4 resulted in reduced invasion and migration ability of NSCLC cells. Mechanistically, silencing B7-H4 activated the adenosine monophosphate-activated protein kinase /mammalian target of rapamycin signaling, which in turn, negatively regulated cell proliferation, stemness, and migration. In conclusion, our results suggest that B7-H4 expression is high in NSCLC tissues, and it has an effect on EMT and cancer stemness. This further suggests that B7-H4 has a potential role in promoting the progression of NSCLC and thereby could be a potential therapeutic target in NSCLC treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Inibidor 1 da Ativação de Células T com Domínio V-Set , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Inibidor 1 da Ativação de Células T com Domínio V-Set/genética , Vimentina/genética
5.
Int J Urol ; 29(6): 578-585, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35218089

RESUMO

OBJECTIVES: Tenascin C is a potential biomarker of cancer-associated fibroblasts and has been significantly associated with poor prognosis in patients with prostate cancer. However, the effects of Tenascin C in prostate cancer cell glycolysis largely remain unclear. Thus, this study aimed to investigate the Tenascin C expression in prostate cancer and its correlation to glycolysis-related protein and gene expression, clinicopathological parameters, and survival of patients. METHODS: We performed immunohistochemical staining for Tenascin C in 141 cases of primary prostate cancer. Based on public data sets, we explored the association of Tenascin C with angiogenesis-related genes, M2 macrophage-related gene, androgen receptor levels, PI3K/AKT/NF-κB pathway genes, and glycolytic enzyme expression. The glucose uptake, lactate production, and glycolytic enzyme levels were detected by glycolysis assay and western blotting. RESULTS: Our results showed that Tenascin C expression is upregulated in prostate cancer tissues compared with benign prostatic hyperplasia tissues. High Tenascin C expression in prostate cancer cells was positively associated with lymph node metastasis, advanced clinical stage, the expression of CD105, CD206, and androgen receptor levels. The Kaplan-Meier curves showed a significant association of Tenascin C expression with the patient's overall survival. Tenascin C expression was positively associated with PI3K p85, pAKT-ser308, and NF-κB p65 protein expression in prostate cancer samples. Moreover, siRNA-mediated knockdown of Tenascin C expression inhibited cell glucose uptake, lactate production, and glycolytic-enzyme expression in prostate cancer cells in vitro. CONCLUSIONS: Together, our findings suggest that Tenascin C is a prognostic marker for patients with prostate cancer and that its effects might be mediated via regulation of the glycolysis process of prostate cancer cells.


Assuntos
Neoplasias da Próstata , Tenascina/metabolismo , Linhagem Celular Tumoral , Glucose , Glicólise , Humanos , Lactatos , Masculino , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias da Próstata/patologia , Receptores Androgênicos/metabolismo , Tenascina/genética
6.
Am J Pathol ; 192(4): 712-721, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35063407

RESUMO

Although glycolysis plays a pivotal role in breast cancer stem-like cell (BCSC) reprogramming, the molecular mechanisms that couple glycolysis to cancer stem-like cells remain unclear. SETD5 is a previously uncharacterized member of the histone lysine methyltransferase family. The goal of this study was to explore the mechanisms underlying the promotion of stem-like and glycolysis activation traits by SETD5. Previous studies have shown that overexpression of SETD5 in breast cancer tissues is associated positively with progression. The present study showed that SETD5 expression was enriched in BCSCs. Down-regulation of SETD5 significantly decreased BCSC properties and glycolysis in vitro and in vivo. Interestingly, SETD5 and glycolytic enzymes were accumulated in the central hypoxic regions of subcutaneous tumor tissues. Bioinformatic analysis predicted SETD5 binding to E1A binding protein p300 (EP300), and subsequently to hypoxia-inducible factor 1α (HIF-1α). The mechanistic study found that SETD5 is an upstream effector of EP300/HIF-1α. SETD5 knockdown reduced the expression of HIF-1α, hexokinase-2, and 6-phosphofructo-2-kinase in the nucleus after treatment with cobalt chloride, a chemical hypoxia mimetic agent that activates HIF-1α to accumulate in the nucleus. Therefore, SETD5 is required for glycolysis in BCSCs through binding to EP300/HIF-1α and could be a potential therapeutic target for breast cancer patients.


Assuntos
Neoplasias da Mama , Metiltransferases , Células-Tronco Neoplásicas , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Glicólise/fisiologia , Humanos , Hipóxia/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metiltransferases/metabolismo , Células-Tronco Neoplásicas/patologia
7.
Emerg Microbes Infect ; 10(1): 2090-2097, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34689717

RESUMO

Since December 2019, coronavirus disease 2019 (COVID-19) caused by SARS coronavirus 2 (SARS-CoV-2) has spread and threatens public health worldwide. The recurrence of SARS-CoV-2 RNA detection in patients after discharge from hospital signals a risk of transmission from such patients to the community and challenges the current discharge criteria of COVID-19 patients. A wide range of clinical specimens has been used to detect SARS-CoV-2. However, to date, a consensus has not been reached regarding the most appropriate specimens to use for viral RNA detection in assessing COVID-19 patients for discharge. An anal swab sample was proposed as the standard because of prolonged viral detection. In this retrospective longitudinal study of viral RNA detection in 60 confirmed COVID-19 patients, we used saliva, oropharyngeal/nasopharyngeal swab (O/N swab) and anal swab procedures from admission to discharge. The conversion times of saliva and anal swab were longer than that of O/N swab. The conversion time of hyper sensitive-CRP was the shortest and correlated with that of CT scanning and viral detection. Some patients were found to be RNA-positive in saliva while RNA-negative in anal swab while the reverse was true in some other patients, which indicated that false negatives were inevitable if only the anal swab is used for evaluating suitability for discharge. These results indicated that double-checking for viral RNA using multiple and diverse specimens was essential, and saliva could be a candidate to supplement anal swabs to reduce false-negative results and facilitate pandemic control.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , SARS-CoV-2/isolamento & purificação , Saliva/virologia , Adulto , Canal Anal/virologia , Reações Falso-Negativas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Orofaringe/virologia , Alta do Paciente , RNA Viral/análise , Estudos Retrospectivos , Adulto Jovem
8.
Exp Mol Pathol ; 121: 104665, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34216584

RESUMO

Abnormal metabolism and uncontrolled angiogenesis are two important characteristics of malignant tumors. Although HBXIP is known to be associated with a poor prognosis for bladder cancer (BC), its effects on glycolysis and angiogenesis in BC have not been investigated. BC prognosis and relative gene expression of HBXIP were analyzed using the GEPIA, UALCAN, and STRING databases. BC cell angiogenesis and glycolysis were assessed by vasculogenic mimicry and glycolysis assay. Human umbilical vein endothelial cell (HUVEC) viability, migration, and angiogenesis were assessed by CCK8, transwell, wound healing, and tube formation assays. The results showed that HBXIP was highly expressed in BC tissues and cells. Knockdown of HBXIP expression decreased the levels of glucose uptake, lactate production, and glycolytic enzyme expression in BC cells, and decreased cell viability and migration of HUVECs. Additionally, silencing HBXIP reduced the total length of tubes and number of intersections, and EPO and VEGF protein expression in BC cells and HUVECs. Furthermore, knockdown of HBXIP expression reversed cell viability, migration, tube formation, and vasculogenic mimicry under high glucose and lactate conditions. Mechanistically, silencing of HBXIP reduced the protein expression levels of pAKT-ser473 and pmTOR, and inhibition of HBXIP, AKT, and mTOR expression decreased glycolytic enzyme protein expression. Our findings suggest that HBXIP reduces glycolysis in BC cells via regulation of AKT/mTOR signaling, thereby blocking BC angiogenesis. Collectively, this study provides a potential strategy to target HBXIP and AKT/mTOR for regulating glycolysis progression concurrently with anti-angiogenesis effects, and thereby develop novel therapeutics for the treatment of BC.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Glicólise , Neovascularização Patológica/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Neoplasias da Bexiga Urinária/irrigação sanguínea , Proteínas Adaptadoras de Transdução de Sinal/genética , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Células Endoteliais da Veia Umbilical Humana , Humanos , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia
9.
Pathol Res Pract ; 218: 153323, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33429327

RESUMO

B7-H4 is a unique negative regulator of T cells that is typically significantly overexpressed in various carcinomas and is associated with poor prognosis. However, the effects of B7-H4 expression on epithelial-mesenchymal transition (EMT) and cancer stemness of colorectal cancer (CRC) are not entirely clear. In the present study, we used tissue samples from 98 patients with CRC and CRC cell lines to determine the clinicopathological significance of B7-H4 in CRC and its effects on CRC stemness. We performed immunohistochemical staining; immunofluorescence imaging; western blotting; and tumor sphere formation, wound healing, transwell migration, and in vivo tumorigenesis assays. B7-H4 expression was upregulated in CRC tissues and was associated with lymph node metastasis, distant metastasis, clinical stage, a shorter overall survival rate, and disease-free survival rate. Cox regression analyses indicated that B7-H4 is an independent poor prognostic factor for CRC. In addition, B7-H4 expression was correlated with the expression of EMT-related proteins and cancer stemness-related proteins. Moreover, immunohistochemical and immunofluorescence analyses revealed that B7-H4 was correlated with CD133 and CD44 expression levels in both CRC tissues and HT29 and HCT116 cell lines. Conversely, B7-H4 knockdown downregulated the expression of EMT- and cancer stemness-related proteins, while inhibiting tumor spheroid formation, cell migration, and invasion of CRC cell lines. These results indicate that B7-H4 can promote EMT and may be a novel stem cell marker, suggesting its potential as a prognostic biomarker for CRC.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/metabolismo , Transição Epitelial-Mesenquimal , Células-Tronco Neoplásicas/metabolismo , Inibidor 1 da Ativação de Células T com Domínio V-Set/metabolismo , Animais , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Intervalo Livre de Doença , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HT29 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , Estadiamento de Neoplasias , Células-Tronco Neoplásicas/patologia , Estudos Retrospectivos , Transdução de Sinais , Inibidor 1 da Ativação de Células T com Domínio V-Set/genética
10.
J Cell Mol Med ; 25(4): 2110-2120, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33314691

RESUMO

Leucine zipper-EF-hand-containing transmembrane protein 1 (LETM1) is a mitochondrial inner membrane protein that is highly expressed in various cancers. Although LETM1 is known to be associated with poor prognosis in colorectal cancer (CRC), its roles in autophagic cell death in CRC have not been explored. In this study, we examined the mechanisms through which LETM1 mediates autophagy in CRC. Our results showed that LETM1 was highly expressed in CRC tissues and that down-regulation of LETM1 inhibited cell proliferation and induced S-phase arrest. LETM1 silencing also suppressed cancer stem cell-like properties and induced autophagy in CRC cells. Additionally, the autophagy inhibitor 3-methyladenine reversed the inhibitory effects of LETM1 silencing on proliferation and stemness, whereas the autophagy activator rapamycin had the opposite effects. Mechanistically, suppression of LETM1 increased the levels of reactive oxygen species (ROS) and mitochondrial ROS by regulation of SOD2, which in turn activated AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR), initiated autophagy, and inhibited proliferation and stemness. Our findings suggest that silencing LETM1 induced autophagy in CRC cells by triggering ROS-mediated AMPK/mTOR signalling, thus blocking CRC progression, which will enhance our understanding of the molecular mechanism of LETM1 in CRC.


Assuntos
Autofagia , Proteínas de Ligação ao Cálcio/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteínas de Membrana/genética , Células-Tronco Neoplásicas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Biomarcadores , Proteínas de Ligação ao Cálcio/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/patologia , Inativação Gênica , Humanos , Imunofenotipagem , Proteínas de Membrana/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Modelos Biológicos , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
11.
Exp Mol Pathol ; 117: 104560, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33127342

RESUMO

SETD8 is a lysine methyltransferase containing an SET domain, which is involved in the carcinogenesis of many cancer types through monomethylation of the histone H4 lysine 20. However, its prognostic value and underlying mechanisms in gastric adenocarcinoma (GA) have not been extensively studied. Here, we assessed SETD8 expression and its relationship with clinicopathological parameters, cancer stemness-related proteins, cell cycle-related proteins, and PI3K/Akt pathway proteins in GA. SETD8 expression in GA tissues was correlated with the primary tumor stage, lymph node metastasis, tumor size, gross type, and clinical stage. SETD8 was an independent predictor of poor overall survival of patients with GA. Cox regression analysis showed that SETD8 is a potential biomarker of unfavorable clinical outcomes in patients with GA. Moreover, SETD8 overexpression was associated with cancer stemness-related genes, cell cycle-related genes, and PI3K/Akt/NF-κB pathway genes in clinical GA tissue samples. SETD8 silencing downregulated the expression of cancer stemness-associated genes (LSD1 and SOX2) and inhibited GA cell proliferation, spheroid formation, invasion, and migration. Additionally, LY294002 significantly reduced the expression of SETD8, pAkt-Ser473, pPI3K-p85, and NFκB-p65 in MKN74 and MKN28 cells. SETD8 may be a novel cancer stemness-associated protein and potential prognostic biomarker in GA.


Assuntos
Adenocarcinoma/genética , Histona Desmetilases/genética , Histona-Lisina N-Metiltransferase/genética , Fatores de Transcrição SOXB1/genética , Neoplasias Gástricas/genética , Adenocarcinoma/patologia , Idoso , Biomarcadores Tumorais/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Cromonas/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Humanos , Masculino , Pessoa de Meia-Idade , Morfolinas/farmacologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Proteína Oncogênica v-akt/genética , Prognóstico , Neoplasias Gástricas/patologia
12.
PLoS One ; 14(4): e0213762, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30973951

RESUMO

In preterm infants (i.e. the gestational age less than 37 weeks), postnatal growth remains a concern. This study used multicenter longitudinal data from China's Under 5 Child Nutrition and Health Surveillance System to investigate the postnatal growth in the weight and length of preterm infants. Gender-stratified differences in weight and length were assessed between preterm and term infants. 1221 preterm infants and 1221 matched term infants were included. The rates of growth in weight and length in preterm infants was greater than those in term infants, especially from the first to sixth month. The rates were higher in males compared to females in the first 3 months. The differences of weight and length between preterm and term infants decreased with increasing age, however, these measurements did not reach the level of their term peers until 12 months before adjusting for gestational age. The median values of weight and length were even larger in preterm infants in the first month after adjusting for gestational age.


Assuntos
Peso Corporal/fisiologia , Desenvolvimento Embrionário/fisiologia , Recém-Nascido Prematuro/crescimento & desenvolvimento , Estado Nutricional/fisiologia , China/epidemiologia , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Masculino
13.
Environ Sci Pollut Res Int ; 21(13): 8167-75, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24677060

RESUMO

The effects of the organic loading rate (OLR) on the performance and the granular sludge characteristics of an expanded granular sludge bed (EGSB) reactor used for treating real traditional Chinese medicine (TCM) wastewater were investigated. Over 90% of the COD removal by the EGSB reactor was observed at the OLRs of 4 to 13 kg COD/(m(3) day). However, increasing the OLR to 20 kg COD/(m(3) day) by reducing the hydraulic retention time (HRT 6 h) reduced the COD removal efficiency to 78%. The volatile fatty acid (VFA) concentration was 512.22 mg/L, resulting in an accumulation of VFAs, and propionic acid was the main acidification product, accounting for 66.51% of the total VFAs. When the OLR increased from 10 to 20 kg COD/(m(3) day), the average size of the granule sludge decreased from 469 to 258 µm. There was an obvious reduction in the concentration of Ca(2+) and Mg(2+) in the granular sludge. The visible humic acid-like peak was identified in the three-dimensional excitation-emission matrix (EEM) fluorescence spectra of the soluble microbial products (SMPs). The fatty acid bond, amide II bond, amide III bond, and C-H bond bending were also observed in the Fourier transform infrared (FTIR) spectra of the SMPs. Methanobacterium formicicum, Methanococcus, and Bacteria populations exhibited significant shifts, and these changes were accompanied by an increase in VFA production. The results indicated that a short HRT and high OLR in the EGSB reactor caused the accumulation of polysaccharides, protein, and VFAs, thereby inhibiting the activity of methanogenic bacteria and causing granular sludge corruption.


Assuntos
Bactérias/metabolismo , Reatores Biológicos , Medicina Tradicional Chinesa , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água/métodos , Análise da Demanda Biológica de Oxigênio , Cálcio/análise , China , Ácidos Graxos Voláteis/análise , Ácidos Graxos Voláteis/metabolismo , Substâncias Húmicas/análise , Magnésio/análise , Resíduos de Serviços de Saúde , Propionatos/análise , Propionatos/metabolismo , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo
14.
Huan Jing Ke Xue ; 34(9): 3513-9, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24288998

RESUMO

The reactive brilliant blue was chosen as the probe pollutant. Fe(NO3)3 concentration, MnSO4 concentration, urea concentration, water bath temperature, calcined temperature and time were as influencing factors, the process parameters of homogeneous precipitation method was optimized for the preparation of bimetallic heterogeneous Fenton-like catalyst as modified sepiolite supported. At the same time, surface chemical characteristics of catalyst were analyzed by SEM, FTIR and XRD. Results showed that: with increasing iron ion concentrations, the active ingredient of the catalyst increased. Adding small amount of manganese ion could inhibit the growth of Fe2O3 diameter and increase the activity of the catalyst. Urea concentration was increased, so that the higher the urea concentration, the higher rate of formation of crystal gains, was conducive to generate small and uniform particles. The optimal conditions were found for preparing bimetallic heterogeneous Fenton-like catalyst by Box-Behnken experiment, which were as follows: concentration of Fe(NO3)3, MnSO4 and urea were 0.18 mol x L(-1), 0.05 mol x L(-1) and 1.0 mol x L(-1), respectively. The dosage of the modified sepiolite was 40 g x L(-1) and water bath temperature was 100 degrees C. Additionally, the catalyst was calcined at 370 degrees C for 3 h. The SEM showed that the sepiolite was an a-type sepiolite, which could be used as a well catalyst support. The infrared spectrum presented the bend vibrations of the Fe-O stretch vibration. The XRD patterns of the catalysts showed the characteristic diffraction peaks of alpha-Fe2O3, and gamma-Fe2O3.


Assuntos
Compostos Férricos/química , Silicatos de Magnésio/química , Catálise , Temperatura
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