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1.
Environ Pollut ; 356: 124307, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38830528

RESUMO

Prokaryotes are effective biosorbents for the recovery of uranium and other heavy metals. However, the potential mechanism of uranium bioaccumulation by filamentous strain (actinobacteria) remains unclear. This study demonstrates the potential for and mechanism of uranium bioaccumulation by living (L-SS) and inactivated (I-SS) Streptomyces sp. HX-1 isolated from uranium mine waste streams. Uranium accumulation experiments showed that L-SS and I-SS had efficient uranium adsorption potentials, with removal rates of 92.93 and 97.42%, respectively. Kinetic and equilibrium data indicated that the bioaccumulation process was consistent with the pseudo-second-order kinetic, Langmuir, and Sips isotherm models. FTIR indicated that the main functional groups of L-SS and I-SS binding uranium were uranyl, carboxyl, and phosphate groups. Moreover, the results of XRD, XPS, SEM-EDS, and TEM-EDS analyses revealed for the first time that L-SS has biomineralization and bioreduction capacity against uranium. L-SS mineralize U(VI) into NH4UO2PO4 and [Formula: see text] through the metabolic activity of biological enzymes (phosphatases). In summary, Streptomyces sp. HX-1 is a novel and efficient uranium-fixing biosorbent for the treatment of uranium-contaminated wastewater.

2.
Chemosphere ; 346: 140646, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37944766

RESUMO

A significant surge in the exploitation of uranium resources has resulted in considerable amounts of radioactive effluents. Thus, efficient and eco-friendly uranium removal strategies need to be explored to ensure ecological safety and resource recovery. In this study, we investigated the resistance of Halomonas campaniensis strain ZFSY-04, isolated from an evaporation pool at a uranium mine site, and its potential mechanism of uranium (Ⅵ) removal. The results showed that the strain exhibited unique uranium tolerance and its growth was not significantly inhibited under a uranium concentration of 700 mg/L. It had a maximum loading capacity of 865.40 mg/g (dry weight), achieved following incubation under uranium concentration of 100 mg/L, pH 6.0, and temperature 30 °C, for 2 h, indicating that the removal of uranium by the strain was efficient and rapid. Combined with kinetic, isothermal, thermodynamic, and microspectral analyses, the mechanism of uranium loading by strain ZFSY-04 was metabolism-dependent and diverse, including, physical and chemical adsorption on the cell surface, extracellular biomineralisation, intracellular bioaccumulation, and biomineralisation. Our results highlight the unique properties of indigenous strains, including high resistance, high efficiency, rapid uranium removal, and various uranium removal strategies, which make it suitable as a new tool for in situ bioremediation and uranium-contaminated environmental resource recovery.


Assuntos
Urânio , Poluentes Radioativos da Água , Urânio/análise , Biodegradação Ambiental , Poluentes Radioativos da Água/análise , Mineração
3.
J Water Health ; 21(8): 1086-1097, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37632383

RESUMO

The adsorption ability of a native Jonesia quinghaiensis strain ZFSY-01, a microorganism isolated from uranium tailing wastewater, to U(VI) in wastewater under different conditions was studied in this work. The results showed that 391.5 mg U/g and 78.3% of adsorption capacity and efficiency were achieved under an optimum adsorption condition, respectively. Especially, the adsorption capacity of this strain reached the maximum (Q=788.9 mg U/g) under 100 mg/L of strain dosage. Simultaneously, the linear regression coefficients for the used isothermal sorption model indicate that the biosorption process is compatible with the Freundlich isotherm, the Temkin isotherm and the Halsey isotherm model. Based on the fitted kinetic parameters, the data from the experiments fit well with models of pseudo-second-order kinetics and intraparticle diffusion, suggesting that the strain ZFSY-01 immobilized U(VI) by physical and chemical adsorption. In addition, thermodynamic parameters demonstrated that the sequestration of U(VI) by the strain is spontaneous and endothermic. Based on the above analysis, strain ZFSY-01 can effectively remove U(VI) ions from high- or low-concentration uranium-containing wastewater and is expected to become a promising biological adsorbent.


Assuntos
Urânio , Águas Residuárias , Cinética , Termodinâmica
4.
Bone ; 67: 156-65, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25019593

RESUMO

MicroRNAs (miRNAs) involve in the regulation of a wide range of physiological processes. Recent studies suggested that miRNAs might play a role in osteoclast differentiation. Here, we identify a new miRNA (miR-9718) in primary mouse osteoclasts that promotes osteoclast differentiation by repressing protein inhibitor of activated STAT3 (PIAS3) at the post-transcriptional level. MiR-9718 was found to be transcribed during osteoclastogenesis, which was induced by macrophage colony stimulating factor (M-CSF) and receptor activator of nuclear factor-κB ligand (RANKL). Overexpression of miR-9718 in RAW 264.7 cells promoted M-CSF and RANKL-induced osteoclastogenesis, whereas inhibition of miR-9718 attenuated it. PIAS3 was predicted to be a target of miR-9718. Luciferase reporter gene validated the prediction. Transfection of pre-miR-9718 in RAW 264.7 cells induced by both M-CSF and RANKL inhibited expression of PIAS3 protein, while the mRNA levels of PIAS3 were not attenuated. In vivo, our study showed that silencing of miR-9718 using a specific antagomir inhibited bone resorption and increased bone mass in mice receiving ovariectomy (OVX) and in sham-operated control mice. Thus, our study showed that miR-9718 played an important role in osteoclast differentiation via targeting PIAS3 both in vitro and in vivo.


Assuntos
Diferenciação Celular/fisiologia , MicroRNAs/fisiologia , Osteoclastos/citologia , Osteoclastos/metabolismo , Proteínas Inibidoras de STAT Ativados/metabolismo , Animais , Diferenciação Celular/genética , Linhagem Celular , Células Cultivadas , Fator Estimulador de Colônias de Macrófagos/farmacologia , Camundongos , MicroRNAs/genética , Proteínas Inibidoras de STAT Ativados/genética , Ligante RANK/farmacologia
5.
Clin Chim Acta ; 423: 116-21, 2013 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-23643930

RESUMO

BACKGROUND: Cytokines including transforming growth factor beta 1 (TGF-ß1) and osteoprotegerin (OPG) are closely related to bone metabolism. However, the relationships between TGF-ß1, OPG and risk of osteoporosis in native Chinese women are unknown. Our research indicated that there is a positive correlation between TGF-ß1 and bone mineral density (BMD) T-score, and a negative correlation between OPG and T-score. The risk of osteoporosis is reduced as TGF-ß1 increases and increases as OPG was raised. We investigated correlations of BMD T-scores with circulating TGF-ß1 and BMD T-scores with circulating OPG in healthy native Chinese women, and to study the effects of changes in TGF-ß1 and OPG on osteoporosis. METHODS: This was a cross-sectional study of 691 healthy native Chinese women aged 20-80 years. Concentrations of serum TGF-ß1 and OPG were determined. BMD T-scores at the posteroanterior spine, left hip, and forearm were measured by dual-energy X-ray absorptiometry. RESULTS: There were positive correlations between serum TGF-ß1 and T-scores at the various skeletal sites (r=0.167-0.285, all P=0.000) and negative correlations between serum OPG and T-scores (r=-0.179 to -0.270, all P=0.007-0.000). After adjusting for age and BMI, correlations between TGF-ß1 and T-score at the lumbar vertebrae and ultradistal forearm, and between OPG and T-score at the ultradistal forearm in premenopausal subjects, remained statistically significant. Multivariate linear stepwise analysis showed that TGF-ß1 could explain 1.9-8.3% of T-score variation at each skeletal site. OPG could explain 2.4-4.4% of T-score variation. When TGF-ß1 and OPG concentrations were grouped according to quartile intervals, T-score and the prevalence and risk of osteoporosis varied with changes in the cytokines. CONCLUSIONS: The risk of osteoporosis in native Chinese women increased as circulating TGF-ß1 was reduced and OPG was raised.


Assuntos
Osteoporose/sangue , Osteoprotegerina/sangue , Fator de Crescimento Transformador beta1/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , China , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
6.
J Bone Miner Res ; 27(7): 1598-606, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22467200

RESUMO

microRNAs (miRNAs) play pivotal roles in osteoblast differentiation. However, the mechanisms of miRNAs regulating osteoblast mineralization still need further investigation. Here, we performed miRNA profiling and identified that miR-93 was the most significantly downregulated miRNA during osteoblast mineralization. Overexpression of miR-93 in cultured primary mouse osteoblasts attenuated osteoblast mineralization. Expression of the Sp7 transcription factor 7 (Sp7, Osterix), a zinc finger transcription factor and critical regulator of osteoblast mineralization, was found to be inversely correlated with miR-93. Then Sp7 was confirmed to be a target of miR-93. Overexpression of miR-93 in cultured osteoblasts reduced Sp7 protein expression without affecting its mRNA level. Luciferase reporter assay showed that miR-93 directly targeted Sp7 by specifically binding to the target coding sequence region (CDS) of Sp7. Experiments such as electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation (ChIP), and promoter luciferase reporter assay confirmed that Sp7 bound to the promoter of miR-93. Furthermore, overexpression of Sp7 reduced miR-93 transcription, whereas blocking the expression of Sp7 promoted miR-93 transcription. Our study showed that miR-93 was an important regulator in osteoblast mineralization and miR-93 carried out its function through a novel miR-93/Sp7 regulatory feedback loop. Our findings provide new insights into the roles of miRNAs in osteoblast mineralization.


Assuntos
MicroRNAs/metabolismo , Osteoblastos/citologia , Fatores de Transcrição/metabolismo , Animais , Imunoprecipitação da Cromatina , Biologia Computacional/métodos , Retroalimentação Fisiológica , Regulação da Expressão Gênica , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/metabolismo , Fator de Transcrição Sp7 , Dedos de Zinco
7.
Zhongguo Zhen Jiu ; 28(12): 873-5, 2008 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-19127911

RESUMO

OBJECTIVE: To observe therapeutic effect of "general regulation" acupuncture and cupping therapy on osteoporosis. METHODS: Sixty cases of primary osteoporosis were treated with the "general regulation" acupuncture-cupping therapy: warming needle moxibustion, plum-blossom needle, moving cupping and retaining the cup, thrice each week, for 3 months. The therapeutic effect was assessed by modified life quality scale for the patient of osteoporosis. RESULTS: Of the 60 cases, 3 cases did not complete the therapeutic course and 48 cases had a significant increase of life quality, the score of the life quality scale decreased from (67.45 +/- 15.67) before treatment to (42.28 +/- 27.89) after treatment with a significant difference (P<0.05). CONCLUSION: The "general regulation" acupuncture-cupping therapy can effectively increase life quality of the patient with osteoporosis, which is an effective therapy for osteoporosis.


Assuntos
Terapia por Acupuntura , Osteoporose/terapia , Qualidade de Vida , Idoso , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Moxibustão , Resultado do Tratamento
8.
Yi Chuan ; 26(6): 865-9, 2004 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-15640118

RESUMO

Karyotype analysis was carried out on quails using the peripheral lymphocyte culture techniques,and G-banding patterns were obtained with trypsin and Giemsa. The results showed that the quail had a diploid number of 78, with 10 pairs of macrochromosomes including the sex-chromosomes and 29 pairs of microchromosomes. NO.1 chromosome was submetacentric, NO.2 and Z chromosome were metacentric,and the others were telocentric, which was slightly different from the results of others. Additionally,analysis of G-banding patterns for macrochromosomes indicated that they were divided into 27 zones and 134 bands.


Assuntos
Bandeamento Cromossômico , Cromossomos/genética , Codorniz/genética , Animais , Diploide , Feminino , Cariotipagem , Masculino , Metáfase
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