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1.
Zhongguo Zhong Yao Za Zhi ; 49(8): 2076-2087, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-38812224

RESUMO

Raphani Semen, with both edible and medicinal values, is a typical Chinese herbal medicine with different effects before and after processing. The raw helps ascending and the cooked helps descending. This paper comprehensively summarizes the differences in chemical constituents and pharmacological effects between raw and processed Raphani Semen that are reported in recent years. Based on the principle of quality markers(Q-markers) of traditional Chinese medicines, the chemical constituent sources, chemical constituent detection techniques, and correlation between bidirectional regulatory efficacy and chemical constituents are compared between raw and processed Raphani Semen. The results suggest that sulforaphene and glucoraphanin could be used as candidate Q-markers of raw and processed Raphani Semen, respectively. This review is expected to provide a reference for further research on the processing, new drug development, and improvement of safety and effectiveness of Raphani Semen in clinical application.


Assuntos
Medicamentos de Ervas Chinesas , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Controle de Qualidade , Humanos , Biomarcadores/análise
2.
Arch Virol ; 168(11): 282, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37889339

RESUMO

miR-HCC2 has been reported to markedly promote the growth, metastasis, and stemness of hepatocellular carcinoma (HCC) cells in vitro and in vivo. Deep sequencing showed that miR-HCC2 was significantly upregulated in hepatitis B virus (HBV)-positive (HBV+) HCC tissue samples compared with HBV-negative (HBV-) HCC tissue samples. miR-HCC2 expression was further evaluated in HCC tissues and cells, and the expression of miR-HCC2 was found to be significantly higher in HBV+ HCC tissues and cells than in HBV- HCC tissues and cells, suggesting that high miR-HCC2 expression could be induced by HBV infection. To explore the relationship between miR-HCC2 and HBV, we investigated the effect of miR-HCC2 on HBV antigen expression, transcription, and replication. We found that miR-HCC2 was involved in the negative feedback regulation of HBV replication. Further mechanistic studies revealed that miR-HCC2 suppressed HBV replication by inhibiting the activity of the enhancer I/X promoter. Our study demonstrates the effect of the inhibition of miR-HCC2 on HBV gene expression and replication, which can help to illustrate the complex regulatory network involving host miRNAs and HBV.


Assuntos
Carcinoma Hepatocelular , Hepatite B , Neoplasias Hepáticas , MicroRNAs , Humanos , Vírus da Hepatite B/genética , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Células Hep G2 , Hepatite B/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Replicação Viral/genética , Regulação Neoplásica da Expressão Gênica
3.
J Asian Nat Prod Res ; 25(11): 1051-1057, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37010914

RESUMO

Two new (1 and 2) meroterpenoids were isolated from the bark of Cinnamomum cassia. Their structures were determined by spectroscopic analyses and chemical methods. Antioxidant activities of 1 and 2 were evaluated by the ORAC and DPPH radical scavenging assays, and the results revealed that compound 2 displayed oxygen radical absorbance capacity. The discovery of compounds 1 and 2 added new members of this kind of natural product.


Assuntos
Cassia , Cinnamomum aromaticum , Cinnamomum aromaticum/química , Antioxidantes/farmacologia , Casca de Planta/química , Extratos Vegetais/química
4.
Molecules ; 28(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36985480

RESUMO

Molybdenum-based cocatalyst being used to construct heterojunctions for efficient photocatalytic H2 production is a promising research hotspot. In this work, CdIn2S4 was successfully closely supported on bulk Mo2C via the hydrothermal method. Based on their matching band structures, they formed a Type Ⅰ heterojunction after the combination of Mo2C (1.1 eV, -0.27 V, 0.83 V) and CdIn2S4 (2.3 eV, -0.74 V, 1.56 V). A series of characterizations proved that the heterojunction composite had higher charge separation efficiency compared to a single compound. Meanwhile, Mo2C in heterojunction could act as an active site for hydrogen production. The photocatalytic H2 production activity of the heterojunction composites was significantly improved, and the maximum activity was up to 1178.32 µmmol h-1 g-1 for 5Mo2C/CdIn2S4 composites. 5Mo2C/CdIn2S4 heterojunction composites possess excellent durability in three cycles (loss of 6%). Additionally, the mechanism of increased activity for composites was also investigated. This study provides a guide to designing noble-metal-free photocatalyst for highly efficient photocatalytic H2 evolution.

5.
Saudi Pharm J ; 31(12): 101829, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37961070

RESUMO

Plumula nelumbinis, a widely used traditional Chinese medicine known for its calming and nerve-soothing properties, contains essential oil as a primary component. However, research on P. nelumbinis essential oil (PNEO) is limited. This study aimed to investigate PNEO components, network target analysis, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses, and antioxidant activity of P. nelumbinis from ten different habitats. GC-MS analysis identified 14 compounds in the essential oil, with CP12 (ß-Sitosterol) having the highest concentration. Five compounds were identified for the first time in P. nelumbinis, with three of them reported for the first time in the Nelumbo. Network target analysis revealed 185 potential targets for 11 compounds and GO and KEGG enrichment analyses showed that PNEO was mainly located in the plasma membrane and could regulate a variety of molecular functions. KEGG pathway enrichment analysis revealed that the essential oil was primarily enriched in pathways related to cancer and the nervous system. PNEO demonstrated strong antioxidant activity, with N8 (Fujiannanping) showing the highest ABTS scavenging capacity and N7 (Hunanxiangtan) showing the highest DPPH radical scavenging capacity. Cell experiments showed that CP4, CP5 and CP10 had protective effects against H2O2-induced oxidative damage. The study suggests that P. nelumbinis from different regions may have slightly different pharmacological effects due to the presence of unique compounds, and further research is necessary to explore the potential therapeutic benefits of PNEO.

6.
Hepatology ; 73(2): 503-519, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32314410

RESUMO

BACKGROUND AND AIMS: Long noncoding RNAs (lncRNAs) have been associated with infection and hepatitis B virus (HBV)-related diseases, though the underlying mechanisms remain unclear. APPROACH AND RESULTS: We obtained HBV-HCC lncRNA profiles by deep sequencing and found HOXA distal transcript antisense RNA (HOTTIP) to be significantly up-regulated. RT-qPCR indicated that HOTTIP is highly expressed in HBV-positive hepatoma tissue and induced by HBV in vitro. Virological experiments showed that HOTTIP significantly suppresses the generation of hepatitis B viral surface antigen, hepatitis B viral e antigen and HBV replication. Homeobox A13 (HOXA13), a downstream factor of HOTTIP, was found to bind to HBV enhancer I and X promotor to repress the production of HBV pregenome RNA (pgRNA) and total RNA as well as HBV replication, suggesting that HOXA13 mediates HOTTIP-induced suppression of HBV replication. More interestingly, HBV DNA polymerase (DNA pol) binds to and stabilizes cAMP-responsive element-binding protein 1 (CREB1) mRNA to facilitate translation of the protein, which, in turn, binds to the regulatory element of HOTTIP to promote its expression. CONCLUSIONS: Our findings demonstrate that HBV DNA pol attenuates HBV replication through activation of the CREB1-HOTTIP-HOXA13 axis. These findings shed light on the mechanism by which HBV restrains replication to contribute to persistent infection.


Assuntos
Carcinoma Hepatocelular/genética , DNA Polimerase Dirigida por DNA/metabolismo , Hepatite B Crônica/genética , Neoplasias Hepáticas/genética , Proteínas Virais/metabolismo , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Vírus da Hepatite B/enzimologia , Vírus da Hepatite B/genética , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Proteínas de Homeodomínio/metabolismo , Interações entre Hospedeiro e Microrganismos/genética , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/genética , Estabilidade Proteica , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Replicação Viral/genética , Adulto Jovem
7.
Molecules ; 27(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36500429

RESUMO

Herein, a novel g-C3N4@Bi/Bi2O2CO3 Z-scheme heterojunction was synthesized via simple methods. UV/Vis diffuse reflectance spectroscopy (DRS) revealed that the visible light absorption range of heterojunction composites was broadened from 400 nm to 500 nm compared to bare Bi2O2CO3. The XRD, XPS and TEM results demonstrated that metal Bi was introduced into g-C3N4@Bi/Bi2O2CO3 composites, and Bi may act as an electronic bridge in the heterojunction. Metal Bi elevated the separation efficiency of carriers, which was demonstrated by photocurrent and photoluminescence. The performance of samples was assessed via the degradation of Rhodamine B (RhB), and the results exhibited that g-C3N4@Bi/Bi2O2CO3 possessed notably boosted photocatalytic activity compared with g-C3N4, Bi2O2CO3 and other binary composites. The heterojunction photocatalysts possessed good photostability and recyclability in triplicate cycling tests. Radical trapping studies identified that h+ and •O2- were two primary active species during the degradation reaction. Based on the energy band position and trapping radical experiments, the possible reaction mechanism of the indirect Z-scheme heterojunction was also proposed. This work could provide an effective reference to design and establish a heterojunction for improving the photocatalytic activity of Bi2O2CO3.


Assuntos
Eletrônica , Luz
8.
Chem Rec ; 20(6): 513-540, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31631504

RESUMO

Heterogeneous catalysis plays a key role in promoting green chemistry through many routes. The functionalizable reactive silanols highlight silica as a beguiling support for the preparation of heterogeneous catalysts. Metal active sites anchored on functionalized silica (FS) usually demonstrate the better dispersion and stability due to their firm chemical interaction with FSs. Having certain functional groups in structure, FSs can act as the useful catalysts for few organic reactions even without the need of metal active sites which are termed as the covetous reusable organocatalysts. Magnetic FSs have laid the platform where the effortless recovery of catalysts is realized just using an external magnet, resulting in the simplified reaction procedure. Using FSs of multiple functional groups, we can envisage the shortened reaction pathway and, reduced chemical uses and chemical wastes. Unstable bio-molecules like enzymes have been stabilized when they get chemically anchored on FSs. The resultant solid bio-catalysts exhibited very good reusability in many catalytic reactions. Getting provoked from the green chemistry aspects and benefits of FS-based catalysts, we confer the recent literature and progress focusing on the significance of FSs in heterogeneous catalysis. This review covers the preparative methods, types and catalytic applications of FSs. A special emphasis is given to the metal-free FS catalysts, multiple FS-based catalysts and magnetic FSs. Through this review, we presume that the contribution of FSs to green chemistry can be well understood. The future perspective of FSs and the improvements still required for implementing FS-based catalysts in practical applications have been narrated at the end of this review.

9.
J Ultrasound Med ; 39(6): 1203-1211, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31891216

RESUMO

OBJECTIVES: By analyzing the B-mode ultrasound and color Doppler flow imaging characteristics of breast lymphoma (BL) and breast infiltrating ductal carcinoma (BIDC), we expected to discriminate these diseases. METHODS: Thirty-two patients with BL and 30 with BIDC confirmed pathologically were selected. The BL group was divided into nodular and diffuse groups. We analyzed and compared the general and imaging characteristics of the BL subgroups and the BIDC group. RESULTS: The mean maximum diameter of BL was 54.93 ± 43.74 cm, and that of BIDC was 23.90 ± 6.79 cm (P < .05). The differences between the nodular BL and BIDC groups in a circumscribed margin (60.00% versus 20.00%), calcification (20.00% versus 53.33%), aggregation characteristics (0.00% versus 53.33%), and density (73.33% versus 10.00%) were statistically significant (P < .05). The differences between the diffuse BL and BIDC groups in calcification (6.67% versus 53.33%), aggregation characteristics (6.67% versus 53.33%) and density (40.00% versus 10.00%) were statistically significant (P < .05). The difference in a circumscribed margin (60% versus 13.33%) between the BL subgroups was statistically significant (P < .05). The blood flow signal in BL lesions was richer than that in BIDC lesions (P < .05). CONCLUSIONS: Extrasuperior-quadrant single lesions in the BL group were larger than those in the BIDC group. The edges of the lesions in the nodular BL group were circumscribed and dense. Lesions in the diffuse BL group did not have a circumscribed margin, calcification, aggregation characteristics, or density. The blood flow signal in BL lesions was richer than that in BIDC lesions.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/diagnóstico por imagem , Linfoma/diagnóstico por imagem , Ultrassonografia Mamária/métodos , Adulto , Idoso , Mama/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
10.
J Asian Nat Prod Res ; 22(8): 746-753, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31163996

RESUMO

Zeaxanthin dipalmitate (3) and two zeaxanthin dipalmitate derivatives, including one new compound (1), were obtained from wolfberry [the fruit of Lycium barbarum L. (Solanaceae)]. Their structures were unambiguously elucidated by spectroscopic analyses. Compound 2 is isolated from the genus Lycium for the first time, and its 1D/2D NMR data are firstly reported. All the compounds belong to carotenoids which are a kind of major bioactive constituents in wolfberry and are also responsible for wolfberry's red color.


Assuntos
Lycium , Frutas , Estrutura Molecular , Palmitatos , Xantofilas
11.
J Gen Virol ; 100(8): 1241-1252, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31204972

RESUMO

In hepatitis B virus (HBV) infection, the virus produces redundant hepatitis B surface antigen (HBsAg) that plays a key role in driving T-cell tolerance and viral persistence. However, currently available anti-HBV agents have no direct effect on HBsAg transcription and protein expression. In this study, we designed a heat shock protein gp96 inhibitor p37 with the cell penetrating peptide PTD (protein transduction domain of trans-activator of transcription), which mediated p37 internalization into hepatocytes. PTD-p37 effectively suppressed HBsAg expression and viral replication both in vitro and in vivo. We further provide evidence that PTD-p37 suppressed HBV enhancer/promoter activity via p53 upregulation. Moreover, PTD-p37 had antiviral activity against a lamivudine-resistant HBV strain. Considering that suppression of HBsAg expression is a major goal for treatment of HBV infection, our results provide a basis for developing a new therapeutic approaches targeting host factors against viral expression.


Assuntos
Antivirais/farmacologia , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/fisiologia , Hepatite B/genética , Glicoproteínas de Membrana/antagonistas & inibidores , Peptídeos/farmacologia , Proteína Supressora de Tumor p53/genética , Animais , Feminino , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Hepatite B/metabolismo , Hepatite B/virologia , Antígenos de Superfície da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Hepatócitos/virologia , Humanos , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Regiões Promotoras Genéticas/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
12.
Biochem Biophys Res Commun ; 513(1): 56-63, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-30935691

RESUMO

Long noncoding RNAs (lncRNAs) regulate gene expression at epigenetic, transcriptional, post-transcriptional levels and play important roles in tumorigenesis and inflammation. In order to explore the effects of lncRNAs on the malignant behavior of cervical cancer (CC) which may be involved in mechanism stimulated by inflammatory factors, we screened a differential expression profile of lncRNAs in CC cells stimulated by TNF-α by deep sequencing. We characterized a significantly upregulated lncRNA LOC105374902 induced by TNF-α. Then, we found that TNF-α accelerated the binding of STAT3 to the promoter region of lncRNA LOC105374902 and promoted its expression. Mechanistically, lncRNA LOC105374902 directly bond to miR-1285-3p as a competing endogenous RNA (ceRNA) to derepress RPL14; functional analysis indicated that both lncRNA LOC105374902 and RPL14 promoted migration, invasion and epithelial-mesenchymal transition (EMT) of CC cells. Taken together, TNF-α-induced lncRNA LOC105374902 may function as a ceRNA for miR-1285-3p to promote the expression of RPL14, promoting the migration, invasion and EMT of CC cells. These findings may provide new insights into the molecular pathogenesis of CC.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , RNA Longo não Codificante/genética , Fator de Necrose Tumoral alfa/metabolismo , Neoplasias do Colo do Útero/genética , Feminino , Células HeLa , Humanos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
13.
J Magn Reson Imaging ; 50(3): 918-929, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30648775

RESUMO

BACKGROUND: The identification of hypoxia inducible factor (HIF-1α) expression is helpful for the quantitative assessment of tumor hypoxia. The application of multimodal imaging techniques may play a part in the assessment of HIF-1α expression of cervical carcinoma. PURPOSE: To investigate the correlations between multiple imaging parameters and HIF-1α expression of early cervical carcinoma and to determine whether tumor hypoxia can be predicted using multisequence imaging parameters. STUDY TYPE: Prospective observational. POPULATION: One hundred patients with early cervical carcinoma. FIELD STRENGTH/SEQUENCES: 3.0 T MRI including intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) perfusion MRI sequences. ASSESSMENT: DCE-MRI and IVIM DWI were performed for all patients. The imaging parameters included volume transfer constant (Ktrans ), rate constant (Kep ), extravascular extracellular volume fraction (Ve ), D, D*, and f. STATISTICAL TESTS: The comparisons of imaging parameters between two independent groups were performed using the Mann-Whitney U-test. Multiple linear regression analysis was performed to determine the correlation between multiple imaging parameters and HIF-1α expression. The diagnostic ability of DCE-MRI, IVIM DWI, and the combination of two techniques for discriminating high-expression and low-expression groups were analyzed. RESULTS: The high-expression group had a lower Ktrans or Kep value than the low-expression group (P = 0.03; 0.02), while the high-expression group had a higher Ve value than the low-expression group (P = 0.03). The high-expression group had a higher D or f value than the low-expression group (P = 0.02; 0.02). Ktrans , Kep , D, Ve , and f values were independently correlated with HIF-1α expression. The sensitivity or accuracy of a combined method was higher than that of DCE-MRI or IVIM DWI individually (P = 0.03, 0.02; 0.04, 0.03). DATA CONCLUSION: The combination of DCE-MRI and IVIM DWI can improve the diagnostic ability of discriminating different HIF-1α expression levels for early cervical tumors. LEVEL OF EVIDENCE: 1 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2019;50:918-929.


Assuntos
Meios de Contraste , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Adulto , Idoso , Colo do Útero/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Estudos Prospectivos , Neoplasias do Colo do Útero/genética
14.
J Virol ; 91(10)2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28148795

RESUMO

MicroRNAs (miRNAs) are a class of small, single-stranded, noncoding, functional RNAs. Hepatitis B virus (HBV) is an enveloped DNA virus with virions and subviral forms of particles that lack a core. It was not known whether HBV encodes miRNAs. Here, we identified an HBV-encoded miRNA (called HBV-miR-3) by deep sequencing and Northern blotting. HBV-miR-3 is located at nucleotides (nt) 373 to 393 of the HBV genome and was generated from 3.5-kb, 2.4-kb, and 2.1-kb HBV in a classic miRNA biogenesis (Drosha-Dicer-dependent) manner. HBV-miR-3 was highly expressed in hepatoma cell lines with an integrated HBV genome and HBV+ hepatoma tumors. In patients with HBV infection, HBV-miR-3 was released into the circulation by exosomes and HBV virions, and HBV-miR-3 expression had a positive correlation with HBV titers in the sera of patients in the acute phase of HBV infection. More interestingly, we found that HBV-miR-3 represses HBsAg, HBeAg, and replication of HBV. HBV-miR-3 targets the unique site of the HBV 3.5-kb transcript to specifically reduce HBc protein expression, levels of pregenomic RNA (pgRNA), and HBV replication intermediate (HBV-RI) generation but does not affect the HBV DNA polymerase level, thus suppressing HBV virion production (replication). This may explain the low levels of HBV virion generation with abundant subviral particles lacking core during HBV replication, which may contribute to the development of persistent infection in patients. Taken together, our findings shed light on novel mechanisms by which HBV-encoded miRNA controls the process of self-replication by regulating HBV transcript during infection.IMPORTANCE Hepatitis B is a liver infection caused by the hepatitis B virus (HBV) that can become a long-term, chronic infection and lead to cirrhosis or liver cancer. HBV is a small DNA virus that belongs to the hepadnavirus family, with virions and subviral forms of particles that lack a core. MicroRNA (miRNA), a small (∼22-nt) noncoding RNA, was recently found to be an important regulator of gene expression. We found that HBV encodes miRNA (HBV-miR-3). More importantly, we revealed that HBV-miR-3 targets its transcripts to attenuate HBV replication. This may contribute to explaining how HBV infection leads to mild damage in liver cells and the subsequent establishment/maintenance of persistent infection. Our findings highlight a mechanism by which HBV-encoded miRNA controls the process of self-replication by regulating the virus itself during infection and might provide new biomarkers for diagnosis and treatment of hepatitis B.


Assuntos
Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , MicroRNAs/genética , Replicação Viral , Replicação do DNA , DNA Viral/metabolismo , Regulação Viral da Expressão Gênica , Hepatite B/sangue , Hepatite B/genética , Hepatite B/imunologia , Hepatite B/virologia , Antígenos do Núcleo do Vírus da Hepatite B/análise , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/imunologia , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Humanos , MicroRNAs/sangue , MicroRNAs/isolamento & purificação , Replicação Viral/genética
15.
J Med Virol ; 89(5): 834-844, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27664977

RESUMO

Hepatitis B virus (HBV) infection is a major health problem worldwide. The roles of microRNAs in the regulation of HBV expression are being increasingly recognized. In this study, we found that overexpression of miR-370 suppressed HBV gene expression and replication in Huh7 cells, whereas antisense knockdown of endogenous miR-370 enhanced HBV gene expression and replication in Huh7 cells and HepG2.2.15 cells. Further, we identified the transcription factor nuclear factor IA (NFIA) as a new host target of miR-370. Overexpression and knockdown studies showed that NFIA stimulated HBV gene expression and replication. Importantly, overexpression of NFIA counteracted the effect of miR-370 on HBV gene expression and replication. Further mechanistic studies showed that miR-370 suppressed HBV replication and gene expression by repressing HBV Enhancer I activity, and one of the NFIA binding site in the Enhancer I element was responsible for the repressive effect of miR-370 on HBV Enhancer I activity. Altogether, our results demonstrated that miR-370 suppressed HBV gene expression and replication through repressing NFIA expression, which stimulates HBV replication via direct regulation on HBV Enhancer I activities. Our findings may provide a new antiviral strategy for HBV infection. J. Med. Virol. 89:834-844, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Regulação Viral da Expressão Gênica , Vírus da Hepatite B/fisiologia , MicroRNAs/metabolismo , Fatores de Transcrição NFI/antagonistas & inibidores , Replicação Viral , Linhagem Celular , Expressão Gênica , Técnicas de Silenciamento de Genes , Hepatócitos/virologia , Humanos
16.
J Nat Prod ; 80(11): 3010-3013, 2017 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-29099182

RESUMO

Houttuynoid M (1), a new houttuynoid, and the related known compound houttuynoid A (2) were isolated from Houttuynia cordata. Their structures were defined using NMR data analysis, HR-MSn experiment, and chemical derivatization. Houttuynoid M is the first example of a houttuynoid with a bis-houttuynin chain tethered to a flavonoid core. A putative biosynthetic pathway of houttuynoid M (1) is proposed. The anti-herpes simplex virus (anti-HSV) activities of 1 and 2 (IC50 values of 17.72 and 12.42 µM, respectively) were evaluated using a plaque formation assay with acyclovir as the positive control.


Assuntos
Antivirais/isolamento & purificação , Antivirais/farmacologia , Flavonoides/isolamento & purificação , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Houttuynia/química , Aciclovir/farmacologia , Aldeídos/química , Antivirais/química , Medicamentos de Ervas Chinesas/química , Flavonoides/química , Flavonoides/farmacologia , Glicosídeos/química , Estrutura Molecular
17.
Appl Microbiol Biotechnol ; 101(5): 2033-2041, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27858137

RESUMO

Psychrophilic enzymes display efficient activity at moderate or low temperatures (4-25 °C) and are therefore of great interest in biotechnological industries. We previously examined the crystal structure of BglU, a psychrophilic ß-glucosidase from the bacterium Micrococcus antarcticus, at 2.2 Å resolution. In structural comparison and sequence alignment with mesophilic (BglB) and thermophilic (GlyTn) counterpart enzymes, BglU showed much lower contents of Pro residue and of charged amino acids (particularly positively charged) on the accessible surface area. In the present study, we investigated the roles of specific amino acid residues in the cold adaptedness of BglU. Mutagenesis assays showed that the mutations G261R and Q448P increased optimal temperature (from 25 to 40-45 °C) at the expense of low-temperature activity, but had no notable effects on maximal activity or heat lability. Mutations A368P, T383P, and A389E significantly increased optimal temperature (from 25 to 35-40 °C) and maximal activity (~1.5-fold relative to BglU). Thermostability of A368P and A389E increased slightly at 30 °C. Mutations K163P, N228P, and H301A greatly reduced enzymatic activity-almost completely in the case of H301A. Low contents of Pro, Arg, and Glu are important factors contributing to BglU's psychrophilic properties. Our findings will be useful in structure-based engineering of psychrophilic enzymes and in production of mutants suitable for a variety of industrial processes (e.g., food production, sewage treatment) at cold or moderate temperatures.


Assuntos
Adaptação Fisiológica/genética , Proteínas de Bactérias/genética , Micrococcus/enzimologia , Micrococcus/metabolismo , beta-Glucosidase/genética , beta-Glucosidase/metabolismo , Sequência de Aminoácidos , Aminoácidos/genética , Proteínas de Bactérias/metabolismo , Temperatura Baixa , Estabilidade Enzimática , Micrococcus/genética , Mutagênese Sítio-Dirigida , Conformação Proteica , Alinhamento de Sequência
18.
Xenobiotica ; 47(4): 284-289, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27237303

RESUMO

1. A filamentous fungus, Cunninghamella blakesleeana CGMCC 3.970, was applied as a microbial system to mimic mammalian metabolism of 4,5-dimethoxyl-canthin-6-one (1). Compound 1 belongs to canthin-6-one type alkaloids, which is a major bioactive constituent of a traditional Chinese medicine (the stems of Picrasma quassioides). 2. After 72 h of incubation in potato dextrose broth, 1 was metabolized to seven metabolites as follows: 4-methoxyl-5-hydroxyl-canthin-6-one (M1), 4-hydroxyl-5-methoxyl-canthin-6-one (M2), canthin-6-one (M3), canthin-6-one N-oxide (M4), 10-hydroxyl-4,5-dimethoxyl-canthin-6-one (M5), 1-methoxycarbonl-ß-carboline (M6), and 4-methoxyl-5-O-ß-D-glucopyranosyl-canthin-6-one (M7). 3. The structures of metabolites were determined using spectroscopic analyses, chemical methods, and comparison of NMR data with those of known compounds. Among them, M7 was a new compound. 4. The metabolic pathways of 1 were proposed, and the metabolic processes involved phase I (O-demethylation, dehydroxylation, demethoxylation, N-oxidation, hydroxylation, and oxidative ring cleavage) and phase II (glycosylation) reactions. 5. This was the first research on microbial transformation of canthin-6-one alkaloid, which could be a useful microbial model for producing the mammalian phase I and phase II metabolites of canthin-6-one alkaloids. 6. 1, M1-M5, and M7 are canthin-6-one alkaloids, whereas M6 belongs to ß-carboline type alkaloids. The strain of Cunninghamella blakesleeana can supply an approach to transform canthin-6-one type alkaloids into ß-carboline type alkaloids.


Assuntos
Biotransformação , Carbolinas/metabolismo , Cunninghamella/metabolismo , Alcaloides Indólicos/metabolismo
19.
Water Sci Technol ; 76(1-2): 1-14, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28708605

RESUMO

This study focuses on detecting trends in annual runoff volume and sediment load in the Yangtze river-lake system. Times series of annual runoff volume and sediment load at 19 hydrological gauging stations for the period 1956-2013 were collected. Based on the Mann-Kendall test at the 1% significance level, annual sediment loads in the Yangtze River, the Dongting Lake and the Poyang Lake were detected with significantly descending trends. The power spectrum estimation indicated predominant oscillations with periods of 8 and 20 years are embedded in the runoff volume series, probably related to the El Niño Southern Oscillation (2-7 years) and Pacific Decadal Oscillation (20-30 years). Based on dominant components (capturing more than roughly 90% total energy) extracted by the proper orthogonal decomposition method, total change ratios of runoff volume and sediment load during the last 58 years were evaluated. For sediment load, the mean CRT value in the Yangtze River is about -65%, and those in the Dongting Lake and the Poyang Lake are -92.2% and -87.9% respectively. Particularly, the CRT value of the sediment load in the channel inflow of the Dongting Lake is even -99.7%. The Three Gorges Dam has intercepted a large amount of sediment load and decreased the sediment load downstream.


Assuntos
Sedimentos Geológicos/química , Lagos/química , Rios/química , China , Monitoramento Ambiental/história , História do Século XX , História do Século XXI , Hidrologia/história
20.
J Transl Med ; 14(1): 189, 2016 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-27349221

RESUMO

BACKGROUND: Occurrence and progression of hepatocellular carcinoma (HCC) are associated with hepatitis B virus (HBV) infection. miR-1269b is up-regulated in HCC cells and tissues. However, the regulation of miR-1269b expression by HBV and the mechanism underlying the oncogenic activity of miR-1269b in HCC are unclear. METHODS: Reverse transcription quantitative PCR (RT-qPCR) was used to measure the expression of miR-1269b and target genes in HCC tissues and cell lines. Western blot analysis was used to assess the expression of miR-1269b target genes and related proteins. Using luciferase reporter assays and EMSA, we identified the factors regulating the transcriptional level of miR-1269b. Colony formation, flow cytometry and cell migration assays were performed to evaluate the phenotypic changes caused by miR-1269b and its target in HCC cells. RESULTS: We demonstrated that the expression levels of pre-miR-1269b and miR-1269b in HBV-positive HepG2.2.15 cells were dramatically increased compared with HBV-negative HepG2 cells. HBx was shown to facilitate translocation of NF-κB from the cytoplasm to the nucleus, and NF-κB binds to the promoter of miR-1269b to enhance its transcription. miR-1269b targets and up-regulates CDC40, a cell division cycle 40 homolog. CDC40 increases cell cycle progression, cell proliferation and migration. Rescue experiment indicated that CDC40 promotes malignancy induced by miR-1269b in HCC cells. CONCLUSION: We found that HBx activates NF-κB to promote the expression of miR1269b, which augments CDC40 expression, contributing to malignancy in HCC. Our findings provide insights into the mechanisms underlying HBV-induced hepatocarcinogenesis.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Proteínas de Ciclo Celular/metabolismo , Movimento Celular/genética , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Fatores de Processamento de RNA/metabolismo , Transativadores/metabolismo , Regulação para Cima/genética , Regiões 3' não Traduzidas/genética , Sequência de Bases , Ciclo Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/genética , Fenótipo , Regiões Promotoras Genéticas , Ligação Proteica/genética , Transcrição Gênica , Proteínas Virais Reguladoras e Acessórias
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