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1.
Ecotoxicol Environ Saf ; 283: 116853, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39137468

RESUMO

The effect and underlying mechanism of tetrabromobisphenol A (TBBPA), a plastic additive, on biofilm formation of methicillin-resistant Staphylococcus aureus (MRSA USA300) remain unknown. This study first investigated the impact of different concentrations of TBBPA on the growth and biofilm formation of USA300. The results indicated that a low concentration (0.5 mg/L) of TBBPA promoted the growth and biofilm formation of USA300, whereas high concentrations (5 mg/L and 10 mg/L) of TBBPA had inhibitory effects. Further exploration revealed that the low concentration of TBBPA enhance biofilm formation by promoting the synthesis of extracellular proteins, release of extracellular DNA (eDNA), and production of staphyloxanthin. RTqPCR analysis demonstrated that the low concentration of TBBPA upregulated genes associated with extracellular protein synthesis (sarA, fnbA, fnbB, aur) and eDNA formation (atlA) and increased the expression of genes involved in staphyloxanthin biosynthesis (crtM), suggesting a potential mechanism for enhanced resistance of USA300 to adverse conditions. These findings shed light on how low concentrations of TBBPA facilitate biofilm formation in USA300 and highlight the indirect impact of plastic additives on pathogenic bacteria in terms of human health. In the future, in-depth studies about effects of plastic additives on pathogenicity of pathogenic bacteria should be conducted. CAPSULE: The protein and eDNA contents in biofilms of methicillin-resistant Staphylococcus aureus are increased by low concentrations of TBBPA.


Assuntos
Biofilmes , Staphylococcus aureus Resistente à Meticilina , Bifenil Polibromatos , Biofilmes/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/fisiologia , Bifenil Polibromatos/toxicidade , Xantofilas , Proteínas de Bactérias/genética
2.
Chem Biodivers ; : e202401646, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39102223

RESUMO

A focused chemical investigation into the polar fractions of a well-known traditional Chinese medicine called Sang-Bai-Pi (the root bark of Morus alba) yielded a panel of prenylated flavanones. The new compounds were identified as four pairs of enantiomers (1a/1b-4a/4b) featuring the same constitution structure, on the basis of HRMS, NMR and ECD analyses. Several previously reported known racemic co-metabolites were also analyzed and separated by HPLC on chiral columns, and the absolute configurations of pure enantiomers were established via ECD technique for the first time. The inhibition of these isolates against the antidiabetic target α-glycosidase was further tested, with most of them showing decent inhibitory activity compared with the positive control acarbose. The interaction mechanism of two selected compounds (3a & 4b) was explored by kinetics experiment, which revealed a mixed type of inhibition pattern toward the enzyme.

3.
Carcinogenesis ; 42(5): 762-771, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33758932

RESUMO

We examined the effect of microRNA-320b (miR-320b) on tumor growth and angiogenesis in lung cancer and also determined its downstream molecular mechanisms. Lung cancer tissues and adjacent non-cancerous tissues were collected from 66 patients with lung cancer. miR-320b expression was experimentally determined to be expressed at low level in cancer tissues. The results of gain-of-function experiments suggested that miR-320b overexpression suppressed cancer cell invasion, tube formation, tumor volume and angiogenesis in xenografted nude mice. Hepatocyte nuclear factor 4 gamma (HNF4G) was identified as a target of miR-320b based on in silico analysis. Dual-luciferase reporter gene assays further identified the binding relationship between HNF4G and miR-320b. Lung cancer tissues exhibited increased expression of HNF4G and insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2). Meanwhile, HNF4G knockdown suppressed IGF2BP2 expression, thereby repressing cancer cell invasion and tube formation. Furthermore, IGF2BP2 modified m6A to increase the expression of thymidine kinase 1 (TK1), thus promoting angiogenesis. In nude mice, restoration of TK1 reversed the suppressive effect of miR-320b overexpression on tumor growth rate and CD31 expression. In conclusion, miR-320b suppresses lung cancer growth and angiogenesis by inhibiting HNF4G, IGF2BP2 and TK1.


Assuntos
Fator 4 Nuclear de Hepatócito/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , Neovascularização Patológica/genética , Proteínas de Ligação a RNA/genética , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Xenoenxertos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Neovascularização Patológica/patologia , Transdução de Sinais/genética
4.
J Cell Mol Med ; 25(8): 4040-4052, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33621431

RESUMO

Hepatocellular cancer (HCC) has been reported to belong to one of the highly vascularized solid tumours accompanied with angiogenesis of human umbilical vein endothelial cells (HUVECs). KDM5A, an attractive drug target, plays a critical role in diverse physiological processes. Thus, this study aims to investigate its role in angiogenesis and underlying mechanisms in HCC. ChIP-qPCR was utilized to validate enrichment of H3K4me3 and KDM5A on the promotor region of miR-433, while dual luciferase assay was carried out to confirm the targeting relationship between miR-433 and FXYD3. Scratch assay, transwell assay, Edu assay, pseudo-tube formation assay and mice with xenografted tumours were conducted to investigate the physiological function of KDM5A-miR-433-FXYD3-PI3K-AKT axis in the progression of HCC after loss- and gain-function assays. KDM5A p-p85 and p-AKT were highly expressed but miR-433 was down-regulated in HCC tissues and cell lines. Depletion of KDM5A led to reduced migrative, invasive and proliferative capacities in HCC cells, including growth and a lowered HUVEC angiogenic capacity in vitro. Furthermore, KDM5A suppressed the expression of miR-433 by demethylating H3K4me3 on its promoterregion. miR-433 negatively targeted FXYD3. Depleting miR-433 or re-expressing FXYD3 restores the reduced migrative, invasive and proliferative capacities, and lowers the HUVEC angiogenic capacity caused by silencing KDM5A. Therefore, KDM5A silencing significantly suppresses HCC tumorigenesis in vivo, accompanied with down-regulated miR-433 and up-regulated FXYD3-PI3K-AKT axis in tumour tissues. Lastly, KDM5A activates the FXYD3-PI3K-AKT axis to enhance angiogenesis in HCC by suppressing miR-433.


Assuntos
Carcinoma Hepatocelular/patologia , Proteínas de Membrana/antagonistas & inibidores , MicroRNAs/genética , Proteínas de Neoplasias/antagonistas & inibidores , Neovascularização Patológica/prevenção & controle , Fosfatidilinositol 3-Quinases/química , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteína 2 de Ligação ao Retinoblastoma/antagonistas & inibidores , Idoso , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína 2 de Ligação ao Retinoblastoma/genética , Proteína 2 de Ligação ao Retinoblastoma/metabolismo , Taxa de Sobrevida , Células Tumorais Cultivadas
5.
Zhonghua Nan Ke Xue ; 26(2): 149-153, 2020 Feb.
Artigo em Zh | MEDLINE | ID: mdl-33346419

RESUMO

OBJECTIVE: To explore the clinical characteristics and prognosis of the 48,XXYY syndrome and gain a deeper insight into this condition. METHODS: This retrospective study included 4 cases of 48,XXYY syndrome confirmed between 2011 and 2018. We analyzed the general information, clinical manifestations, laboratory results, imaging features and outcomes of assisted reproductive technology (ART) of the patients and reviewed the relevant literature. RESULTS: The 4 patients with 48,XXYY syndrome were characterized by low literacy, soft texture and small volume of the testis, high levels of FSH and LH, and low level of serum T. Two of them were diagnosed with ejaculatory dysfunction and aspermia, and the other 2 with normal ejaculatory function but azoospermia. Biochemical analysis of seminal plasma indicated normal quantifications of both fructose and neutral α glucosidase. ART with donor sperm was performed for all the 4 cases and 3 of them got full-term babies. CONCLUSIONS: The 48,XXYY syndrome is often complicated by hypergonadotropic hypogonadism, with the clinical manifestations of aspermia or non-obstructive azoospermia. ART with donor sperm can be employed to help the patient with 48,XXYY syndrome get their non-biological offspring.


Assuntos
Transtornos dos Cromossomos Sexuais/diagnóstico , Azoospermia/genética , Humanos , Masculino , Técnicas de Reprodução Assistida , Estudos Retrospectivos , Sêmen/química , Transtornos dos Cromossomos Sexuais/patologia , Testículo
6.
Molecules ; 24(11)2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31163647

RESUMO

Lepidium meyenii is now widely consumed as a functional food and medicinal product, which is known as an enhancer of reproductive health. However, the specific chemical composition and mechanism of action for improving sexual function are unclear. The present study aims at screening and determining the potential compounds, which promote mouse leydig cells (TM3) proliferation. The partial least squares analysis (PLS) was employed to reveal the correlation between common peaks of high performance liquid chromatography (HPLC) fingerprint of L. meyenii and the proliferation activity of TM3. The results suggested that three compounds had good activities on the proliferation of TM3 and promoting testosterone secretion, there were N-benzyl-hexadecanamide, N-benzyl-(9z,12z)-octadecadienamide and N-benzyl-(9z,12z,15z)-octadecatrienamide which might be the potential bioactive markers related to the enhancing sexual ability functions of L. meyenii. The first step in testosterone synthesis is the transport of cholesterol into the mitochondria, and the homeostasis of mitochondrial function is related to cyclophilin D (CypD). In order to expound how bioactive ingredients lead to promoting testosterone secretion, a molecular docking simulation was used for further illustration in the active sites and binding degree of the ligands on CypD. The results indicated there was a positive correlation between the binding energy absolute value and testosterone secretion activity. In addition, in this study it also provided the reference for a simple, quick method to screen the promoting leydig cell proliferation active components in traditional Chinese medicine (TCM).


Assuntos
Lepidium/química , Células Intersticiais do Testículo/citologia , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Análise dos Mínimos Quadrados , Células Intersticiais do Testículo/efeitos dos fármacos , Ligantes , Masculino , Camundongos , Simulação de Acoplamento Molecular , Análise Multivariada , Compostos Fitoquímicos/química , Testosterona/metabolismo
7.
J Agric Food Chem ; 72(32): 17938-17952, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39092914

RESUMO

Fifteen stilbenoid derivatives, including five previously undescribed ones (albaphenols A-E, 1-5) with diverse scaffolds, were obtained from the well-known agricultural economic tree Morus alba. Their structures, including absolute stereochemistries, were fully characterized by detailed interpretation of spectroscopic data and quantum chemical computational analyses of nuclear magnetic resonance (NMR) and electric circular dichroism (ECD). Albaphenol A (1) features an unprecedented rearranged carbon skeleton incorporating a novel 2-oxaspiro[bicyclo[3.2.1]octane-6,3'-furan] motif; albaphenol C (3) is likely derived from a cometabolite through an interesting intramolecular transesterification reaction; and albaphenol E (5) bears a cleavage-reconnection scaffold via a dioxane ring. All of the compounds exhibited significant inhibition against the diabetic target α-glucosidase, with low to submicromole IC50 values (0.70-8.27 µM), and the binding modes of selected molecules with the enzyme were further investigated by fluorescence quenching, kinetics, and molecular docking experiments. The antidiabetic effect of the most active and abundant mulberrofuran G (6) was further assessed in vivo in diabetic mice, revealing potent antihyperglycemic activity and comparable antidiabetic efficacy to the clinical drug acarbose.


Assuntos
Inibidores de Glicosídeo Hidrolases , Hipoglicemiantes , Simulação de Acoplamento Molecular , Morus , Extratos Vegetais , Estilbenos , alfa-Glucosidases , Animais , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Camundongos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Estilbenos/química , Estilbenos/farmacologia , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo , Masculino , Morus/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Cinética
8.
J Ethnopharmacol ; 322: 117645, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38147942

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Morus alba L. (mulberry) is a well-known medicinal species that has been used by herbalist doctors for the treatment of diabetes for a long history, and modern ethnopharmacological studies have demonstrated the ameliorating effects of different mulberry extracts toward diabetes-related symptoms and identified a number of α-glucosidase inhibitors as hypoglycemic ingredients. AIM OF THE STUDY: The present study aims to explore new potent α-glucosidase inhibitors from the root bark of M. alba (known as Sang-Bai-Pi in traditional medicine) based on an in vivo antidiabetic evaluation of its extract fractions and further characterize the preliminary mechanism of the new active constituents. MATERIALS AND METHODS: α-Glucosidase inhibitory assay and diabetic mice model were used to locate and evaluate the active fractions from the extract. Diverse separation techniques (e.g. Sephadex LH-20 column chromatograph (CC) and HPLC) and spectroscopic methods (e.g. MS, NMR and ECD) were employed to isolate and structurally characterize the obtained constituents, respectively. Fluorescence quenching, kinetics and molecular docking experiments were conducted to investigate the enzyme inhibitory mechanism of the active compounds. RESULTS: The 80% ethanol eluate from the macroporous resin CC exerted good antidiabetic effects in the tested mice. Fifty-two flavonoids including 22 new ones were then separated and identified, and most of them showed strong inhibition against α-glucosidase with their structure-activity relationship being also discussed. The four new most active ingredients were further characterized to be mixed type of α-glucosidase inhibitors, and their binding modes with the enzyme were also explored. CONCLUSIONS: Our current work has demonstrated that the root bark of M. alba is an extremely rich source of flavonoids as potent α-glucosidase inhibitors and potential antidiabetic agents, which makes it a promising candidate species to develop new natural remedies for the prevention and treatment of diabetes.


Assuntos
Diabetes Mellitus Experimental , Morus , Camundongos , Animais , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/química , alfa-Glucosidases/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Simulação de Acoplamento Molecular , Morus/química , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/química , Extratos Vegetais/uso terapêutico , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Flavonoides/química
9.
Phytochemistry ; 213: 113787, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37414237

RESUMO

Eighteen previously unreported pregnane glycosides, namely marsdenosides S1-S18, along with 15 known analogues, have been isolated from the stems of Marsdenia tenacissima. The structures of the undescribed compounds were elucidated by spectroscopic means, and their absolute configurations were established on the basis of time-dependent density functional theory (TD-DFT) based electronic circular dichroism (ECD) calculation, X-ray crystallography and acid hydrolysis. All the isolates were evaluated for their chemo-reversal ability against P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) in MCF-7/ADR cell line, and nine ones displayed moderate MDR reversal activity with reversal folds in the range of 2.45-9.01. The most active 12-O-acetyl-20-O-benzoyl-(14,17,18-orthoacetate)-dihydrosarcostin-3-O-ß-d-thevetopyranosyl-(1 â†’ 4)-O-ß-d-oleandropyranosyl-(1 â†’ 4)-O-ß-d-cymaropyranoside increased the sensitivity of MCF-7/ADR cell to adriamycin comparably to the reference drug verapamil (RF = 8.93).


Assuntos
Marsdenia , Marsdenia/química , Estrutura Molecular , Glicosídeos/farmacologia , Glicosídeos/química , Pregnanos/farmacologia , Pregnanos/química , Resistência a Múltiplos Medicamentos
10.
Fitoterapia ; 168: 105551, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37247696

RESUMO

Twenty compounds comprising four pregnane steroids (2-4 & 20) and 16 pregnane glycosides (1 & 5-19) have been obtained from the ethanol extract of the roots of a Dai ethnological herb, Marsdenia tenacissima. Their structures were characterized on the basis of comprehensive spectroscopic analyses with 17 ones (1-17) being reported for the first time, including the rare cases (2 & 3) of free C21 steroids with 17α-acetyl substitution, compounds 4-7 bearing an unusual 14α-OH, and the first examples with simultaneous 14α-OH/17α-acetyl substitution (7) and glycosylation at C-12 position (10 & 11). An empirical rule for the identification of C-17 configuration, in C21 steroids incorporating the marsdenin constitution structure, was also proposed. All the isolates, along with an array of previously reported analogues in our compound library, were screened for their chemo-reversal ability against P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) in MCF-7/ADR cell line, and six compounds exhibited moderate MDR reversal activity with reversal folds ranging from 1.92 to 4.44.


Assuntos
Marsdenia , Marsdenia/química , Estrutura Molecular , Esteroides/farmacologia , Esteroides/química , Pregnanos/farmacologia , Pregnanos/química , Glicosídeos/farmacologia , Glicosídeos/química , Resistência a Múltiplos Medicamentos
11.
Phytochemistry ; 205: 113506, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36347308

RESUMO

Eleven undescribed glycosylated C21 steroids and nine known homologous glycosides with diverse acyl substituents, as well as their common steroid aglycone, have been obtained from the roots of Marsdenia tenacissima. Their structures were elucidated mainly by comprehensive spectroscopic analyses and comparison with previously reported analogues, with the absolute configuration assignment being supported by chemical degradation, X-ray crystallography and ECD exciton chirality method. Among them, two pairs of regioisomers were found to exist as inseparable equilibrium mixtures due to an interesting intramolecular transesterification, and nicotinoyl substitution was first reported for metabolites from the title plant. Screening of these compounds in a panel of bioassays revealed that two glycosides displayed mild inhibition against butyrylcholinesterase.


Assuntos
Marsdenia , Butirilcolinesterase , Esteroides/farmacologia
12.
Fitoterapia ; 164: 105354, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36403943

RESUMO

Chemical fractionation of the EtOH extract of the roots of a traditional Chinese herb, Morinda officinalis, afforded an array of methyl 2-naphthoate derivatives (1-9) including four pairs of enantiomers (1-4), two pimarane diterpenes and two ursane triterpenoids. Among them, eight compounds (1a/1b-3a/3b, 11 and 13) were reported in the current work for the first time. The structures of the new compounds, including their absolute configurations, were defined by spectroscopic analyses in combination with quantum chemical electronic circular dichroism (ECD) and gauge-independent atomic orbital (GIAO) NMR calculations. All the isolates were evaluated for their inhibitory effect on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in murine RAW264.7 macrophage cells, and the enantiomers 1a and 3b exhibited moderate activity with IC50 values of 41.9 and 26.2 µM. Meanwhile, compound 3b also dose-dependently inhibited the secretion of two pro-inflammatory cytokines TNF-α and IL-6 in the same cell model.


Assuntos
Morinda , Rubiaceae , Animais , Camundongos , Morinda/química , Estrutura Molecular , Anti-Inflamatórios/farmacologia , Extratos Vegetais/química , Óxido Nítrico
13.
Foods ; 12(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36613392

RESUMO

The health benefits of Vaccinium bracteatum are well recorded in ancient Chinese medical books and were also demonstrated by modern researches. However, the relationship between its beneficial functions and specific chemical constituents has not been fully characterized. This study investigated the bioactive small-molecule constituents in the leaves of V. bracteatum, which afforded 32 compounds including ten new ones (1-9) and ten pairs of enantiomers (9-18). Their structures with absolute configurations were elucidated by spectroscopic methods, especially nuclear magnetic resonance (NMR) and electronic circular dichroism (ECD) analyses, with 1-4 bearing a novel revolving-door shaped scaffold. While half-compounds exhibited decent antioxidant activity by scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, all except 19 and 20 exerted significant capturing activity against diammonium 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) radicals. In addition, the new iridoids 1, 5, 6, and 7 exerted apparent neuroprotective activity toward PC12 cells, with 1 being comparable to the positive control, and selective compounds also displayed anti-diabetic and anti-inflammatory properties by inhibiting α-glucosidase and NO production, respectively. The current work revealed that the bioactive small-molecule constituents could be closely related to the functional food property of the title species.

15.
Huan Jing Ke Xue ; 42(6): 2826-2838, 2021 Jun 08.
Artigo em Zh | MEDLINE | ID: mdl-34032082

RESUMO

Inland waters are vital sinks for active carbon (C) and potential sources of greenhouse gas emissions. In this study, the characteristics of dissolved carbon dioxide (CO2) and methane (CH4) concentrations in the Nantiaoxi River system in the upper reaches of the Taihu Lake basin were observed between Jul. 2019 and Nov. 2019 (summer and autumn) using headspace equilibration-gas chromatography. Simultaneously, physical and chemical parameters were also determined to understand the factors influencing dissolved CO2 and CH4 concentrations. The results showed that the mean dissolved CO2 concentrations and saturation levels in water were (505.47±16.99) µg·L-1 and (256.31±8.32)%, respectively, and the corresponding values for CH4 were (1.88±0.09) µg·L-1 and (5218.74±264.30)%, respectively. The saturation levels of dissolved CO2 and CH4 at all observation points were greater than 100%, indicating that the Nantiaoxi River system is a potential source of CO2 and CH4. The highest mean dissolved CO2 concentrations in water were found in agricultural areas followed by residential and forest areas, and there were significant differences among the three land-use types. The mean dissolved CH4 concentrations in the water in residential areas were significantly higher than those in agricultural area forest areas. The dissolved CO2 concentrations, saturation levels of CO2, dissolved CH4 concentrations, and saturation levels of CH4 in water were all negatively correlated with oxidation reduction potential (ORP) (P<0.01) and positively correlated with electrical conductivity (EC) (P<0.01). The discrepancies in chlorophyll (Chl-a), nitrate (NO3--N), total nitrogen (TN), and EC were the main reasons for differences in dissolved CO2 concentrations among the different land use types. Phytoplankton growth could be promoted by the higher input of nitrogen pollutants into rivers in agricultural and residential areas, and respiration could be also enhanced, resulting in higher dissolved CO2 concentrations. The higher concentrations of dissolved organic carbon (DOC) and ammonium nitrogen (NH4+-N) in the water, and the water temperature in residential areas, were probably the main causes of the higher dissolved CH4 concentrations. Rainfall also had some influence on dissolved CO2 and CH4 concentrations in the water associated with the different land use types. Specifically, higher concentrations of nitrogen pollutants and the enhancement of DOC were the main drivers of high dissolved CO2 concentrations in agricultural areas as well as the higher dissolved CH4 concentrations in residential areas following rainfall events.

16.
Int J Genomics ; 2021: 6670390, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33816607

RESUMO

BACKGROUND: MicroRNAs (miRNAs) have been demonstrated to exhibit important regulatory roles in multiple malignancies, including hepatocellular carcinoma (HCC). hsa-miR-497-5p was reported to involve in cancer progression and poor prognosis in many kinds of tumors. However, the expression and its clinical significance of hsa-miR-497-5p in HCC remain unclear. METHODS: In the present study, we investigated the expression of hsa-miR-497-5p in HCC and analyzed the correction of clinical features with prognosis. The expression levels of hsa-miR-497-5p and potential target genes were analyzed in HCC and adjacent noncancerous tissues using The Cancer Genome Atlas (TCGA) database and Gene Expression Omnibus (GEO) datasets. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to analyze hsa-miR-497-5p levels in 328 HCC tissues and 30 paired adjacent noncancer tissues. Overall survival (OS) and progression-free survival (PFS) of patients with HCC were assessed using the Kaplan-Meier method and the log-rank test. RESULTS: The hsa-miR-497-5p expression levels were decreased, and its target genes ACTG1, CSNK1D, PPP1CC, and BIRC5 were upregulated in HCC tissues compared with normal tissues. Lower levels of hsa-miR-497-5p expression and higher levels of the four target genes were significantly associated with higher tumor diameter. Moreover, patients with lower hsa-miR-497-5p expression and higher target genes levels had shorter OS. CONCLUSION: The expression levels of hsa-miR-497-5p may play an important regulatory role in HCC and are closely correlated with HCC progression and poor prognosis in patients. The hsa-miR-497-5p may be a specific therapeutic target for the treatment of HCC.

17.
Ying Yong Sheng Tai Xue Bao ; 32(9): 3070-3078, 2021 Sep.
Artigo em Zh | MEDLINE | ID: mdl-34658191

RESUMO

Soil denitrifying enzyme activity (DEA) was measured by acetylene inhibition technique, along with exploration of factors influencing DEA in a bamboo forest riparian zone in the upper reaches of the Taihu Lake Basin during summer. Our aim was to provide important insights into the assessment of ecological functions of bamboo forest riparian zone on reducing nitrogen pollution in rivers. The results showed that the riparian soil DEA ranged from 6.32 to 23.22 µg N·kg-1·h-1, with a mean value of 14.65 µg N·kg-1·h-1. The vertical distribution (0-40 cm soil profile) of DEA was affected by several factors, such as soil organic carbon (SOC), total nitrogen (TN), nitrate nitrogen (NO3--N), soil water content, and activity of carbon and nitrogen hydrolase, which resulted in decreased DEA with increasing soil depth. The horizontal changes in DEA (at the same soil depth but at different distances from river) was mainly governed by the variation in SOC concentration. In this area, the concentration of soil dissolved organic carbon was relatively low, which might inhibit the soil DEA during summer.


Assuntos
Lagos , Solo , Carbono/análise , China , Florestas
18.
Mol Ther Nucleic Acids ; 23: 702-718, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33575116

RESUMO

Hepatocellular carcinoma (HCC) is one of the deadliest malignant tumors that are harmful to human health. Increasing evidence has underscored the critical role of the competitive endogenous RNA (ceRNA) regulatory networks among various human cancers. However, the complexity and behavior characteristics of the ceRNA network in HCC were still unclear. In this study, we aimed to clarify a phosphatase and tensin homolog (PTEN)-related ceRNA regulatory network and identify potential prognostic markers associated with HCC. The expression profiles of three RNAs (long non-coding RNAs [lncRNAs], microRNAs [miRNAs], and mRNAs) were extracted from The Cancer Genome Atlas (TCGA) database. The DLEU2L-hsa-miR-100-5p/ hsa-miR-99a-5p-TAOK1 ceRNA network related to the prognosis of HCC was obtained by performing bioinformatics analysis. Importantly, we identified the DLEU2L/TAOK1 axis in the ceRNA by using correlation analysis, and it appeared to become a clinical prognostic model by Cox regression analysis. Furthermore, methylation analyses suggested that the abnormal upregulation of the DLEU2L/TAOK1 axis likely resulted from hypomethylation, and immune infiltration analysis showed that the DLEU2L/TAOK1 axis may have an impact on the changes in the tumor immune microenvironment and the development of HCC. In summary, the current study constructing a ceRNA-based DLEU2L/TAOK1 axis might be a novel important prognostic factor associated with the diagnosis and prognosis of HCC.

19.
Am J Transl Res ; 13(1): 168-182, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33527016

RESUMO

Lung cancer has high incidence and mortality rates, in which lung squamous cell carcinoma (LUSC) is a primary type of non-small cell lung carcinoma (NSCLC). The aim of our study was to discover long non-coding RNAs (lncRNAs) associated with diagnose and prognosis for LUSC. RNA sequencing data obtained from LUSC samples were extracted from The Cancer Genome Atlas database (TCGA). Two prognosis-associated lncRNAs (including SFTA1P and LINC00519) were selected from LUSC samples, and the expression levels were also verified to be associated abnormal in LUSC clinical samples. Our findings demonstrate that lncRNAs SFTA1P and LINC00519 exert important functions in human LUSC and may serve as new targets for LUSC diagnosis and therapy.

20.
Cell Death Discov ; 7(1): 224, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34455417

RESUMO

Hepatocellular carcinoma (HCC) is a heterogeneous tumor with an increased incidence worldwide accompanied by high mortality and dismal prognosis. Emerging evidence indicates that mesenchymal stem cells (MSCs)-derived exosomes possess protective effects against various human diseases by transporting microRNAs (miRNAs or miRs). We aimed to explore the role of exosomal miR-15a derived from MSCs and its related mechanisms in HCC. Exosomes were isolated from transduced MSCs and co-incubated with Hep3B and Huh7 cells. miR-15a expression was examined by RT-qPCR in HCC cells, MSCs, and secreted exosomes. CCK-8, transwell, and flow cytometry were used to detect the effects of miR-15a or spalt-like transcription factor 4 (SALL4) on cell proliferative, migrating, invasive, and apoptotic properties. A dual-luciferase reporter gene assay was performed to validate the predicted targeting relationship of miR-15a with SALL4. Finally, in vivo experiments in nude mice were implemented to assess the impact of exosome-delivered miR-15a on HCC. The exosomes from MSCs restrained HCC cell proliferative, migrating, and invasive potentials, and accelerated their apoptosis. miR-15a was expressed at low levels in HCC cells and could bind to SALL4, thus curtailing the proliferative, migrating, and invasive abilities of HCC cells. Exosomes successfully delivered miR-15a to HCC cells. Exosomal miR-15a depressed tumorigenicity and metastasis of HCC tumors in vivo. Overall, exosomal miR-15a from MSCs can downregulate SALL4 expression and thereby retard HCC development.

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