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1.
Nanotechnology ; 33(20)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-34983034

RESUMO

BiFeO3is a photocatalyst with excellent performance. However, its applications are limited due to its wide bandgap. In this paper, MIL-101(Fe)@BiOI composite material is synthesized by hydrothermal method and then calcined at high temperature to obtain BiFeO3@Bi5O7I composite material with high degradation capacity. Among them, an n-n heterojunction is formed, which improves the efficiency of charge transfer, and the recombination of light-generated electrons and holes promotes improved photocatalytic efficiency and stability. The result of photocatalytic degradation of tetracycline under visible light irradiation showed, BiFeO3@Bi5O7I (1:2) has the best photodegradation effect, with a degradation rate of 86.4%, which proves its potential as a photocatalyst.

2.
J Environ Manage ; 251: 109542, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31569024

RESUMO

Microbial community is sensitive to the variations of environment, and it plays an important role in biogeochemical cycling in acid mine drainage (AMD). In this study, an integrated high-throughput absolute abundance quantification (iHAAQ) method was applied to study the dynamics of microbial community and the characteristics of microorganism. The results showed a significant difference in bacterial community with diversity being higher in watershed area. The main influential factors for bacterial communities in watershed were physicochemical properties (e.g., pH and potassium), while in mining areas the main driving factors were metals/metalloids (e.g., As, Zn, and Pb). Notably, the major functions of microbial community were transporter and ABC transporter in mining area, while two-component system was more abundant in watershed by the Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation analysis (level 3). In particular, Phyllobacterium, Bacteroides, and Sulfurovum were demonstrated to be potentially useful bacterial species for bioremediation, which should be a good choice for future studies. These results could facilitate our understanding of microbial diversity in different sediments of mining areas and identify microbial communities for bioremediation projects.


Assuntos
Microbiota , Rios , Ácidos , Bactérias , Mineração
3.
BMC Med Imaging ; 18(1): 45, 2018 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-30470257

RESUMO

BACKGROUND: Physical examinations may reveal the instability of a glenohumeral joint but cannot diagnose the bony Bankart lesions. Soft tissue Bankart lesion cannot be visualized on traditional radiogram. Magnetic resonance images have high cost and availability issues. The purpose of the study was to access the diagnostic performance of the Computed Tomography (CT) in the assessment of patients with shoulder instability and to diagnose the Bankart and bony Bankart lesions. METHODS: A total of 145 patients with shoulder instability were included in the study. Patients were subjected to clinical examination tests, traditional radiography, and CT. Two orthopedic surgeons, two engineers (trained in musculoskeletal imaging), and two physiotherapists have analyzed the radiological images, CT scans, and the clinical examination tests respectively. The Chi-square test or one-way ANOVA/ Dunnett Multiple comparisons test was performed at 99% of confidence level. RESULTS: Sensitivity (0.972 ± 0.18 vs. 1, p = 0.11) and accuracy (0.942 ± 0.17 vs. 1, p < 0.0001, q = 3.88) for the clinical examination tests combining the traditional radiological images were same to CT. However, the clinical examination tests combining the traditional radiological images had more inconclusive results (5 vs. 1), false-positive results (6 vs. 5), and false negative results (4 vs. 1) than CT. The area that detects the Bankart and bony Bankart lesions at least one time for CT was higher than that of the clinical examination tests combining the traditional radiological images. CONCLUSION: CT should be considered for evaluation in patients with shoulder instability and suspected Bankart and bony Bankart lesions. TRIAL REGISTRATION: Researchregistry3990 dated 15 December 2014 ( www.researchregistry.com ).


Assuntos
Lesões de Bankart/diagnóstico por imagem , Instabilidade Articular/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Lesões de Bankart/complicações , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Instabilidade Articular/complicações , Masculino , Variações Dependentes do Observador , Medição da Dor , Estudos Prospectivos , Sensibilidade e Especificidade , Inquéritos e Questionários , Adulto Jovem
4.
Am J Respir Cell Mol Biol ; 50(5): 870-5, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24450537

RESUMO

Malignant pleural mesothelioma (MPM) is a rare malignancy of the pleura that is frequently resistant to conventional therapies. Immunotherapy is a promising investigational approach for MPM that has shown some evidence of clinical benefit in select patients. However, tumor-induced immunosuppression is likely a major impediment to achieving optimal clinical responses to immunotherapeutic intervention. MPM contains a variable degree of infiltrating T-regulatory cells and M2 macrophages, which are believed to facilitate tumor evasion from the host immune system. Additional immunosuppressive factors identified in other human tumor types, such as tumor-associated programmed death ligand-1 expression, may be relevant for investigation in MPM. Conventional cytoreductive therapies, such as radiation, chemotherapy, and surgery, may play a critical role in successful immunotherapeutic strategies by ablating intratumoral and/or systemic immunosuppressive factors, thus creating a host environment more amenable to immunotherapy. This article reviews the immunotherapeutic approaches being evaluated in patients with MPM and discusses how immunotherapy might be rationally combined with conventional tumor cytoreductive therapies for this disease.


Assuntos
Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/terapia , Mesotelioma/imunologia , Mesotelioma/terapia , Neoplasias Pleurais/imunologia , Neoplasias Pleurais/terapia , Animais , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Humanos , Imunoterapia/métodos , Mesotelioma Maligno , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Sci Rep ; 14(1): 10149, 2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698048

RESUMO

This study aims to investigate the potential impact of high-dose radiotherapy (RT) on brain structure, cognitive impairment, and the psychological status of patients undergoing brain tumor treatment. We recruited and grouped 144 RT-treated patients with brain tumors into the Low dose group (N = 72) and the High dose group (N = 72) according to the RT dose applied. Patient data were collected by using the HADS and QLQ-BN20 system for subsequent analysis and comparison. Our analysis showed no significant correlation between the RT doses and the clinicopathological characteristics. We found that a high dose of RT could aggravate cognitive impairment and deteriorate patient role functioning, indicated by a higher MMSE and worsened role functioning in the High dose group. However, the depression status, social functioning, and global health status were comparable between the High dose group and the Low dose group at Month 0 and Month 1, while being worsened in the High dose group at Month 3, indicating the potential long-term deterioration of depression status in brain tumor patients induced by high-dose RT. By comparing patient data at Month 0, Month 1, Month 3, Month 6, and Month 9 after RT, we found that during RT treatment, RT at a high dose could aggravate cognitive impairment in the short term and lead to worsened patient role functioning, and even deteriorate the overall psychological health status of patients in the long term.


Assuntos
Neoplasias Encefálicas , Disfunção Cognitiva , Humanos , Masculino , Feminino , Disfunção Cognitiva/etiologia , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/psicologia , Pessoa de Meia-Idade , Idoso , Encéfalo/efeitos da radiação , Encéfalo/patologia , Adulto , Dosagem Radioterapêutica , Depressão/etiologia , Qualidade de Vida
6.
Aging (Albany NY) ; 15(6): 1918-1930, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36934373

RESUMO

The up-regulation of katanin P80 has been reported to be correlated with a larger tumor size and lymph node metastasis in non-small-cell lung cancer (NSCLC) patients. And lncRNA MALAT1 was demonstrated to promote the proliferation of chronic myeloid leukemia cells via modulating miR-328. 135 lung cancer patients were divided into 6 groups according to their genotypes of MALAT1. The expression of KATNB1 was negatively correlated with the GGGT genotype of MALAT1. Decreased lymph node size and tumor size of brain metastatic lung were observed in patients with GGGT genotype of MALAT1. The luciferase activities of MALAT1 and KATNB1 were remarkably suppressed by miR-328 in A549 and H460. And the down-regulation of MALAT1 or up-regulation of miR-328 significantly repressed the KATNB1 expression in A549 and H460 cells. MALAT1 expression was reduced in patients carrying haplotype GGGT. A signaling pathway of MALAT1/miR-328/KATNB1 was established to explain the down-regulation of KATNB1 mRNA in patients carrying haplotype GGGT and reduced lymph node size in lung cancer and tumor size in brain metastatic lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Humanos , Encéfalo/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Haplótipos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Linfonodos/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo
7.
Microorganisms ; 11(9)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37764029

RESUMO

In this study, an acclimated manganese-oxidizing bacteria (MnOB) consortium, QBS-1, was enriched in an acid mine area; then, it was used to eliminate Mn(Ⅱ) in different types of wastewater. QBS-1 presented excellent Mn removal performance between pH 4.0 and 8.0, and the best Mn-removal efficiency was up to 99.86% after response surface methodology optimization. Unlike other MnOB consortia, the core bacteria of QBS-1 were Stenotrophomonas and Achromobacter, which might play vital roles in Mn removal. Besides that, adsorption, co-precipitation and electrostatic binding by biological manganese oxides could further promote Mn elimination. Finally, the performance of the Mn biofilter demonstrated that QBS-1 was an excellent inoculant, which indicates good potential for removing Mn contamination steadily and efficiently.

8.
Materials (Basel) ; 15(2)2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35057225

RESUMO

In the study, ZIF-8@BIOI composites were synthesized by the hydrothermal method and then calcined to acquire the ZnO@Bi5O7I composite as a novel composite for the photocatalytic deterioration of the antibiotic tetracycline (TC). The prepared ZnO@Bi5O7I composites were physically and chemically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmet-Teller (BET) surface area, UV-Vis diffuse reflectance spectroscopy (DRS), emission fluorescence spectra, transient photocurrent response, electrochemical impedance spectra and Mott-Schottky. Among the composites formed an n-n heterojunction, which increased the separation efficiency of electrons and holes and the efficiency of charge transfer. After the photocatalytic degradation test of TC, it showed that ZnO@Bi5O7I (2:1) had the best photodegradation effect with an 86.2% removal rate, which provides a new approach to the treatment of antibiotics such as TC in wastewater.

9.
J Hazard Mater ; 403: 123674, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33264876

RESUMO

The widespread of polybrominated diphenyl ethers (PBDEs) in the environment has caused rising concerns, and it is an urgent endeavor to find a proper way for PBDEs remediation. Various techniques such as adsorption, hydrothermal and thermal treatment, photolysis, photocatalytic degradation, reductive debromination, advanced oxidation processes (AOPs) and biological degradation have been developed for PBDEs decontamination. A comprehensive review of different PBDEs remediation techniques is urgently needed. This work focused on the environmental source and occurrence of PBDEs, their removal and degradation methods from water and soil, and prospects for PBDEs remediation techniques. According to the up-to-date literature obtained from Web of Science, it could be concluded that (i) photocatalysis and photocatalytic degradation is the most widely reported method for PBDEs remediation, (ii) BDE-47 and BDE-209 are the most investigated PBDE congeners, (iii) considering the recalcitrance nature of PBDEs and more toxic intermediates could be generated because of incomplete degradation, the combination of different techniques is the most potential solution for PBDEs removal, (iv) further researches about the development of novel and effective PBDEs remediation techniques are still needed. This review provides the latest knowledge on PBDEs remediation techniques, as well as future research needs according to the up-to-date literature.

10.
Environ Technol ; 42(10): 1623-1633, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31580199

RESUMO

This study aimed to investigate the effects of red mud-based-passivator (RM-based-passivator) on rice yield, cadmium (Cd) in brown rice, pH and available Cd in Cd-polluted soil by pot experiments, and to explore the adsorption mechanism of the passivator by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX), fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) analysis. The results showed that this passivator obviously improved the pH, reduced the available Cd in soil and the Cd content in brown rice in Changsha Cd polluted soil (CS soil), while had little effect on Hengyang Cd polluted soil (HY soil). Compared with the control, the soil pH increased in the range from 0.31 to 1.37, the available Cd in soil decreased in the range from 13.25% to 52.34%, and the total Cd in brown rice decreased in the range from 46.44% to 84.98% in CS soil. Considering the impacts of RM-based-passivator on the growth of rice, the Cd content in brown rice, and the pH and available Cd in soil, 0.10-0.30% (w/w) of the passivator is recommended to apply in CS soil but not in HY soil. Based on the analysis of SEM, EDX, FTIR and XRD, the mechanism of Cd(II) adsorption by RM-based-passivator included physical adsorption, surface complexation and ion exchange. The present results indicated that the appropriate addition of RM-based-passivator could be an effective strategy for the remediation of acidic Cd-polluted soils.


Assuntos
Oryza , Poluentes do Solo , Adsorção , Cádmio/análise , Solo , Poluentes do Solo/análise
11.
J Hazard Mater ; 396: 122631, 2020 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-32339872

RESUMO

A bacterial consortium for efficient decontamination of high-concentration Fe-Mn acid mine drainage (AMD) was successfully isolated. The removal efficiencies of Fe and Mn were effective, reaching 99.8 % and 98.6 %, respectively. High-throughput sequencing of the 16S rRNA genes demonstrated that the microbial community had changed substantially during the treatment. The Fe-Mn oxidizing bacteria Flavobacterium, Brevundimonas, Stenotrophomonas and Thermomonas became dominant genera, suggesting that they might play vital roles in Fe and Mn removal. Moreover, the pH of culture increased obviously after incubation, which was benefit for depositing Fe and Mn from AMD. The specific surface area of the biogenic Fe-Mn oxides was 108-121 m2/g, and the surface contained reactive oxygen functional groups (-OH and -COOH), which also improved Fe and Mn removal efficiency. Thus, this study provides an alternative method to treat AMD containing high concentrations of Fe and Mn.


Assuntos
Manganês , Poluentes Químicos da Água , Bactérias/genética , Ferro/análise , Manganês/análise , Oxirredução , RNA Ribossômico 16S/genética , Poluentes Químicos da Água/análise
13.
Clin Respir J ; 12(6): 2020-2028, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29356386

RESUMO

OBJECTIVES: Autoantibodies tumor-associated antigens (TAAs) could be a valuable tool for the diagnosis or early detection of cancer due to their relatively high specificity and stability. The purpose of this study is to detect the level of tumor-associated autoantibodies in lung cancer and assess the diagnostic potential of autoantibodies in screening strategy for early stage lung cancer. MATERIALS AND METHODS: Levels of tumor-associated autoantibodies (AAbs) were measured against a panel of seven TAAs (p53, PGP9.5, SOX2, GAGE7, GBU4-5, CAGE and MAGEA1) in 397 patients with pulmonary lesions (305 with newly diagnosis of NSCLC, 47 with SCLC and 45 with benign nodule) and 74 control persons without any nodules in the lung after chest MDCT scan. The sensitivity, specificity for patients and control persons, positive rate of the panel in different pathology, stage, size of lesion, age and gender were compared and analyzed. RESULTS: The AAbs panel could distinguish malignant lesions from benign lesions and control people, with sensitivity of 56.53% and specificity of 91.60%. The specificity could be further increased to 95.80%, when combined with CT. The AAbs also showed high diagnostic value of malignant nodule, and it would be a new method for judgment of malignant nodules that are less than 8 mm in diameter. No significant differences were seen based on pathology, NSCLC stages, tumor size, age or gender. CONCLUSION: This assay confirms the value of AAbs panel as a diagnostic tool combined with CT scan.


Assuntos
Autoanticorpos/análise , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Detecção Precoce de Câncer/métodos , Neoplasias Pulmonares/diagnóstico , Autoanticorpos/imunologia , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/imunologia , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Curva ROC
14.
Sci Rep ; 7: 42612, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28198402

RESUMO

Recently there has been a more focus on the development of an efficient technique for detection of circulating tumor cells (CTCs), due to their significance in prognosis and therapy of metastatic cancer. However, it remains a challenge because of the low count of CTCs in the blood. Herein, a rapid and high-sensitivity approach for CTCs detection using an integrated microfluidic system, consisting of a deterministic lateral displacement (DLD) isolating structure, an automatic purifying device with CD45-labeled immunomagnetic beads and a capturing platform coated with rat-tail collagen was reported. We observed high capture rate of 90%, purity of about 50% and viability of more than 90% at the high throughput of 1 mL/min by capturing green fluorescent protein (GFP)-positive cells from blood. Further capturing of CTCs from metastatic cancers patients revealed a positive capture rate of 83.3%. Furthermore, our device was compared with CellSearch system via parallel analysis of 30 cancer patients, to find no significant difference between the capture efficiency of both methods. However, our device displayed advantage in terms of time, sample volume and cost for analysis. Thus, our integrated device with sterile environment and convenient use will be a promising platform for CTCs detection with potential clinical application.


Assuntos
Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas , Neoplasias/diagnóstico , Células Neoplásicas Circulantes/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Estudos de Casos e Controles , Linhagem Celular Tumoral , Sobrevivência Celular , Terapia Combinada , Feminino , Imunofluorescência , Humanos , Masculino , Microscopia de Fluorescência , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias/terapia
15.
J Neurosci ; 23(13): 5897-905, 2003 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-12843294

RESUMO

Gs(alpha) is a subunit of the heterotrimeric G-protein complex, expressed ubiquitously in all types of cells, including neurons. Drosophila larvae, which have mutations in the Gs(alpha) gene, are lethargic, suggesting an impairment of neuronal functions. In this study, we examined synaptic transmission at the neuromuscular synapse in Gs(alpha)-null (dgsR60) embryos shortly before they hatched. At low-frequency nerve stimulation, synaptic transmission in mutant embryos was not very different from that in controls. In contrast, facilitation during tetanic stimulation was minimal in dgsR60, and no post-tetanic potentiation was observed. Miniature synaptic currents (mSCs) were slightly smaller in amplitude and less frequent in dgsR60 embryos in normal-K+ saline. In high-K+ saline, mSCs with distinctly large amplitude occurred frequently in controls at late embryonic stages, whereas those mSCs were rarely observed in dgsR60 embryos, suggesting a developmental defect in the mutant. Using the Gal4-UAS expression system, we found that these phenotypes in dgsR60 were caused predominantly by lack of Gs(alpha) in presynaptic neurons and not in postsynaptic muscles. To test whether Gs(alpha) couples presynaptic modulator receptors to adenylyl cyclase (AC), we examined the responses of two known G-protein-coupled receptors in dgsR60 embryos. Both metabotropic glutamate and octopamine receptor responses were indistinguishable from those of controls, indicating that these receptors are not linked to AC by Gs(alpha). We therefore suggest that synaptic transmission is compromised in dgsR60 embryos because of presynaptic defects in two distinct processes; one is uncoupling between the yet-to-be-known modulator receptor and AC activation, and the other is a defect in synapse formation.


Assuntos
Embrião não Mamífero/fisiologia , Subunidades alfa Gs de Proteínas de Ligação ao GTP/deficiência , Terminações Pré-Sinápticas/fisiologia , Transmissão Sináptica/fisiologia , Adenilil Ciclases/metabolismo , Animais , Cálcio/metabolismo , Drosophila , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/genética , Estimulação Elétrica , Embrião não Mamífero/inervação , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Expressão Gênica , Mutação , Junção Neuromuscular/fisiologia , Técnicas de Patch-Clamp , Terminações Pré-Sinápticas/metabolismo , Subunidades Proteicas/deficiência , Subunidades Proteicas/genética , Receptores de Amina Biogênica/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Transmissão Sináptica/genética , Transgenes
16.
Protein Cell ; 5(6): 420-44, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24756565

RESUMO

Chemical synapses are asymmetric intercellular junctions through which neurons send nerve impulses to communicate with other neurons or excitable cells. The appropriate formation of synapses, both spatially and temporally, is essential for brain function and depends on the intercellular protein-protein interactions of cell adhesion molecules (CAMs) at synaptic clefts. The CAM proteins link pre- and post-synaptic sites, and play essential roles in promoting synapse formation and maturation, maintaining synapse number and type, accumulating neurotransmitter receptors and ion channels, controlling neuronal differentiation, and even regulating synaptic plasticity directly. Alteration of the interactions of CAMs leads to structural and functional impairments, which results in many neurological disorders, such as autism, Alzheimer's disease and schizophrenia. Therefore, it is crucial to understand the functions of CAMs during development and in the mature neural system, as well as in the pathogenesis of some neurological disorders. Here, we review the function of the major classes of CAMs, and how dysfunction of CAMs relates to several neurological disorders.


Assuntos
Moléculas de Adesão Celular/metabolismo , Sinapses/metabolismo , Animais , Moléculas de Adesão Celular/química , Humanos , Doenças do Sistema Nervoso/metabolismo , Doenças do Sistema Nervoso/patologia , Plasticidade Neuronal , Neurônios/metabolismo , Mapas de Interação de Proteínas
17.
Bioresour Technol ; 167: 276-83, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24995877

RESUMO

Haematococcus pluvialis is the best source of natural astaxanthin known as "the king of antioxidants". The mass outdoor culture is the most workable strategy for astaxanthin production, but the effects of daytime and night temperatures on the biomass concentration and astaxanthin content of H. pluvialis have received little attention. This study indicated that, raising the daytime or night temperature could stimulate night accumulation of astaxanthin until temperature up to 28°C; the night biomass loss increased firstly and then decreased along with the daytime temperature reducing; decreasing the night temperature can lessen night biomass loss; the daytime temperature of 28°C and the night temperature below 28°C were optimal for achieving high biomass and astaxanthin content. Subsequently, the outdoor culture strategy has been improved and can increase the net biomass and astaxanthin productivities by 5 and 2.9-fold as compared to the former strategy.


Assuntos
Técnicas de Cultura de Células/métodos , Clorófitas/crescimento & desenvolvimento , Clorófitas/efeitos da radiação , Temperatura , Biomassa , Clorófitas/metabolismo , Fotoperíodo , Xantofilas/metabolismo
18.
Bioresour Technol ; 163: 26-32, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24787315

RESUMO

As the optimal source of astaxanthin, Haematococcus pluvialis was cultured for commercial production of astaxanthin through two continuous phases: cell growth and astaxanthin induction. In this study, the efficiency of an attached system for producing astaxanthin from H. pluvialis was investigated and compared to that of the suspended system (bubble column bioreactor) under various conditions. Results showed that this attached system is more suitable for photoinduction of H. pluvialis than the suspended bioreactor. Under the optimal conditions, the astaxanthin productivity of the attached system was 65.8 mg m(-2)d(-1) and 2.4-fold of that in the suspended system. This attached approach also offers other advantages over suspended systems, such as, producing astaxanthin under a wide range of light intensities and temperatures, saving water, ease to harvest cells, resisting contamination. Therefore, the attached approach can be considered an economical, environmentally friendly and highly-efficient technology for producing astaxanthin from H. pluvialis.


Assuntos
Clorófitas/metabolismo , Fotoquímica , Fotobiorreatores , Xantofilas/metabolismo
19.
J Thorac Cardiovasc Surg ; 145(2): 496-504, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23174177

RESUMO

OBJECTIVES: Hyperthermic chemotherapy perfusion has been used in the treatment of both pleural and peritoneal mesothelioma without an extensive basic science foundation. Clinical data are limited with no prospective randomized trials to support the use of this potentially toxic therapy. We sought to generate basic scientific support for this clinical practice and to define the optimal conditions for use in future clinical trials. METHODS: Growth of a variety of in vitro established cell lines, including a hyperthermia-sensitive Chinese hamster ovary (CHO)-K1 cell line, a normal lung fibroblast line (MRC-5), a lung cancer line (A549), and 3 human mesothelioma cell lines (NCI-H28, NCI-H2052, and MSTO-211H), was assessed using a novel tetrazolium compound (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt [MTS]) and an electron coupling reagent (phenazine methosulfate), which measures the absorbance at 490 nm of a formazan product reduced from MTS by living cells (MTS metabolic assay), or a standard dilution clonogenic assay, which enumerates colony-forming units of more than 50 cells. Each cell line was plated into flasks and then exposed to varying combinations of chemotherapy agents and hyperthermia (37°C-45°C). The cells then were harvested and assessed in either assay. The role of chemotherapeutic agents currently most commonly used in clinical practice, including cisplatin, gemcitabine, and pemetrexed, was assessed with and without simultaneous heat exposure. RESULTS: Conditions initially were explored using hyperthermia alone in CHO-K1, A549, and NCI-H28 cell lines using temperatures of 37°C, 42°C, and 45°C for 20, 40, and 60 minutes, respectively. This showed a reproducible dose-response curve in CHO-K1 cells with increasing temperature producing lower survival to only 1.5% of the control at 45°C for 60 minutes (P < .01). The A549 cells also showed a response but only at the highest temperature, and the NCI-H28 cells showed a more modest reduction to 65% at 45°C for 60 minutes (P < .01). When the 2 assays were directly compared, the MTS assay failed to detect differences between groups and therefore was discontinued from the remainder of these experiments. Next, hyperthermia was limited to the physiologic limit of 42°C, and the addition of chemotherapy was assessed. Doses were chosen on the basis of prior pharmacokinetic data from studies showing a maximum tissue/blood level of 200 ng/mL for cisplatin pleural instillation and were thought to more accurately reflect actual tumor levels. Cisplatin alone modestly reduced the clonogenic potential to 26%, 16.4%, and 13.6% at 42°C, respectively, for 60 minutes (P < .01); however, this was only a further reduction of 29.6%, 33.8%, and 34.2%, respectively, from the cisplatin alone control. Therefore, most of the reduction was attributable to chemotherapy and not hyperthermia. With combinations of cisplatin/gemcitabine and cisplatin/pemetrexed, the effect was larger, with reduction to 9.6%, 0%, and 0%, respectively (P < .01) (incremental reduction of 16.5%, 0%, and 0%, respectively, due to hyperthermia). Cisplatin/pemetrexed produced essentially identical results. CONCLUSIONS: Intrapleural chemotherapy seems to be most effective when using 2 drug combinations. All mesothelioma cell lines showed no particular sensitivity to heat. The use of hyperthermia alone or with chemotherapy produces at best only a modest effect and does not necessarily support its current clinical use.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Proliferação de Células/efeitos dos fármacos , Hipertermia Induzida , Mesotelioma/patologia , Neoplasias Pleurais/patologia , Animais , Células CHO , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Terapia Combinada , Cricetinae , Cricetulus , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Glutamatos/farmacologia , Guanina/análogos & derivados , Guanina/farmacologia , Humanos , Pemetrexede , Fatores de Tempo , Ensaio Tumoral de Célula-Tronco , Gencitabina
20.
J Gen Appl Microbiol ; 56(6): 491-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21282905

RESUMO

Locus afe_0454 from Acidithiobacillus ferrooxidans (At.ferrooxidans) is annotated as related to copper resistance in The Institute for Genomic Research database. In our study, two At.ferrooxidans strains, 26(#) and DC, with different levels of copper ion resistance were isolated from acid mine drainages at two major copper mines in China, and their copper-resistance capacity was determined. The 26(#) strain had a copper-tolerance level of 0.22 mol/L, whereas the DC strain had a lower copper-tolerance level of 0.04 mol/L. The mutant 26(#) was generated from strain 26(#), and its copper-tolerance level was 0.25 mol/L. Using real-time quantitative reverse transcription polymerase chain reaction, differential expression of the afe_0454 gene during copper ion stress of these three strains was investigated. The results showed that the expression of afe_0454 was increased under copper ion stress, indicating that the afe_0454 gene is sensitive to copper levels. Furthermore, the afe_0454 gene expression ratio varied in the different copper-resistant strains. Gene expression was highest in the highest copper-resistant strain. The deduced amino acid sequence of the afe_0454 gene was 56.87% non-polar, indicating the AFE_0454 protein was hydrophobic. Searching with the AFE_0454 protein in The Institute for Genomic Research database showed that the structure of the copper resistance protein D (CopD), which transports copper ions outside of the cell, had the highest sequence identity (46%). Bioinformatics analysis showed that the AFE_0454 protein has eight transmembrane helixes and was predicted to be localized to the plasma membrane. These results strongly suggested that the AFE_0454 protein is likely a transmembrane protein and might be directly involved in copper ion resistance.


Assuntos
Acidithiobacillus/genética , Cobre/metabolismo , Cobre/farmacologia , Farmacorresistência Bacteriana , Acidithiobacillus/efeitos dos fármacos , Sequência de Aminoácidos , China , Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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