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1.
Int J Neurosci ; 132(3): 269-282, 2022 Mar.
Article in English | MEDLINE | ID: mdl-33208009

ABSTRACT

BACKGROUND: Cognitive decline is one of the greatest concerns for patients with Parkinson's disease (PD) and their care partners. Repetitive transcranial magnetic stimulation (rTMS) is a nonpharmacological treatment option used to improve cognitive function in PD, but its efficacy is unclear. We performed a meta-analysis to determine whether rTMS improves cognition in PD patients. METHODS: Eligibility criteria (PICOS) were as follows: (1) 'P': The patients participating were diagnosed with idiopathic PD; (2) 'I': Intervention using rTMS; (3) 'C': Sham stimulation as control; (4) 'O': The outcome of the study included cognitive evaluations; (5) 'S': The study adopted randomized controlled design. The standardized mean difference (SMD) of change of score was applied to measure efficacy, and we used Version 2 of the Cochrane tool to assess risk of bias. RESULTS: Twelve studies met the inclusion criteria. Compared with sham-controlled group, the pooled result showed a non-significant short-term effect of rTMS on global cognition (SMD: -0.15, 95% CI: -0.59 to 0.29, I2 = 36.7%), executive function (SMD: 0.03, 95% CI: -0.21 to 0.26, I2 = 0.0%), and attention and working memory (SMD: 0.05, 95% CI: -0.25 to 0.35, I2 = 0.0%). Long-term outcomes were either shown to be statistically nonsignificant. CONCLUSIONS: Based on a limited number of studies, rTMS fails to improve cognition in PD. We call for additional high-quality randomized controlled trials with adequate sample sizes to determine the efficacy of rTMS.


Subject(s)
Cognitive Dysfunction , Parkinson Disease , Cognition , Humans , Parkinson Disease/complications , Parkinson Disease/therapy , Randomized Controlled Trials as Topic , Transcranial Magnetic Stimulation , Treatment Outcome
2.
World J Clin Cases ; 9(30): 9159-9167, 2021 Oct 26.
Article in English | MEDLINE | ID: mdl-34786400

ABSTRACT

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) is a rare and life-threatening disease caused by inherited pathogenic mutations and acquired dysregulations of the immune system. Composite lymphoma is defined as two or more morphologically and immunophenotypically distinct lymphomas that occur in a single patient. Here, we report two cases of HLH secondary to composite lymphoma with mixed lineage features of T- and B-cell marker expression both in the bone marrow and lymph nodes in adult patients. CASE SUMMARY: Two patients were diagnosed with HLH based on the occurrence of fever, pancytopenia, lymphadenopathy, splenomegaly, hemophagocytosis and hyperferritinemia. Immunohistochemical staining of the axillary lymph node and bone marrow in case 1 showed typical features of combined B-cell and T-cell lymphoma. In addition, a lymph node gene study revealed rearrangement of the T-cell receptor chain and the immunoglobulin gene. Morphology and immunohistochemistry studies of a lymph node biopsy in case 2 showed typical features of T cell lymphoma, but immunophenotyping by flow cytometry analysis of bone marrow aspirate showed B cell lymphoma involvement. The patients were treated with high-dose methylprednisolone combined with etoposide to control aggressive HLH progression. The patients also received immunochemotherapy with the R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) regimen immediately after diagnosis. Both patients presented with highly aggressive lymphoma, and died of severe infection or uncontrolled HLH. CONCLUSION: We present two rare cases with overwhelming hemophagocytosis along with composite T- and B-cell lymphoma, which posed a diagnostic dilemma. HLH caused by composite lymphoma was characterized by poor clinical outcomes.

3.
Article in English | MEDLINE | ID: mdl-34567221

ABSTRACT

BACKGROUND: Parkinson's disease (PD) is the second most common neurodegenerative disease worldwide, which currently lacks disease-modifying therapy to slow down its progression. Idebenone, a coenzyme Q10 (CQ10) analogue, is a well-known antioxidant and has been used to treat neurological disorders. However, the mechanism of Idebenone on PD has not been fully elucidated. This study aims to predict the potential targets of Idebenone and explore its therapeutic mechanism against PD. METHOD: We obtained potential therapeutic targets through database prediction, followed by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis. Next, we constructed and analyzed a protein-protein interaction network (PPI) and a drug-target-pathway-disease network. A molecular docking test was conducted to identify the interactions between Idebenone and potential targets. Lastly, a PD cell line of SH-SY5Y overexpressing mutant α-synuclein was used to validate the molecular mechanism. RESULT: A total of 87 targets were identified based on network pharmacology. The enrichment analysis highlighted manipulation of MAP kinase activity and the PI3K-AKT signaling pathway as potential pharmacological targets for Idebenone against PD. Additionally, molecular docking showed that AKT and MAPK could bind tightly with Idebenone. In the cell model of PD, Idebenone activated autophagy and promoted α-synuclein degradation by suppressing the AKT/mTOR pathway. Pretreating cells with chloroquine (CQ) to block autophagic flux could diminish the pharmacological effect of Idebenone to clear α-synuclein. CONCLUSION: This study demonstrated that Idebenone exerts its anti-PD effects by enhancing autophagy and clearance of α-synuclein, thus providing a theoretical and experimental basis for Idebenone therapy against PD.

4.
Math Biosci Eng ; 17(4): 3736-3766, 2020 05 22.
Article in English | MEDLINE | ID: mdl-32987553

ABSTRACT

We study a quasi-one-dimensional steady-state Poisson-Nernst-Planck type model for ionic flows through a membrane channel with three ion species, two positively charged with the same valence and one negatively charged. Bikerman's local hard-sphere potential is included in the model to account for ion sizes. The problem is treated as a boundary value problem of a singularly perturbed differential system. Under the framework of a geometric singular perturbation theory, together with specific structures of this concrete model, the existence and uniqueness of solutions to the boundary value problem for small ion sizes is established. Furthermore, treating the ion sizes as small parameters, we derive an approximation of individual fluxes, from which one can further study the qualitative properties of ionic flows and extract concrete information directly related to biological measurements. Of particular interest is the competition between two cations due to the nonlinear interplay between finite ion sizes, diffusion coefficients and boundary conditions, which is closely related to selectivity phenomena of open ion channels with given protein structures. Furthermore, we are able to characterize the distinct effects of the nonlinear interplays between these physical parameters. Numerical simulations are performed to identify some critical potentials which play critical roles in examining properties of ionic flows in our analysis.

5.
Oncol Rep ; 43(6): 1863-1874, 2020 06.
Article in English | MEDLINE | ID: mdl-32236588

ABSTRACT

Lung cancer has one of the highest mortalities of any cancer worldwide. Triptolide (TP) is a promising tumor suppressor extracted from the Chinese herb Tripterygium wilfordii. Our previous proteomics analysis revealed that TP significantly interfered with the ribosome biogenesis pathway; however, the underlying molecular mechanism remains poorly understood. The aim of the present study was to determine the molecular mechanism of TP's anticancer effect by investigating the association between ribosomal stress and p53 activation. It was found that TP induces nucleolar disintegration together with RNA polymerase I (Pol I) and upstream binding factor (UBF) translocation. TP interrupted ribosomal (r)RNA synthesis through inhibition of RNA Pol I and UBF transcriptional activation. TP treatment increased the binding of ribosomal protein L23 (RPL23) to mouse double minute 2 protein (MDM2), resulting in p53 being released from MDM2 and stabilized. Activation of p53 induced apoptosis and cell cycle arrest by enhancing the activation of p53 upregulated modulator of apoptosis, caspase 9 and caspase 3, and suppressing BCL2. In vivo experiments showed that TP significantly reduced xenograft tumor size and increased mouse body weight. Immunohistochemical assays confirmed that TP significantly increased the p53 level and induced nucleolus disintegration, during which nucleolin distribution moved from the nucleolus to the nucleoplasm, and RPL23 clustered at the edge of the cell membrane. Therefore, it was proposed that TP induces ribosomal stress, which leads to nucleolus disintegration, and inhibition of rRNA transcription and synthesis, resulting in increased binding of RPL23 with MDM2. Consequently, p53 is activated, which induces apoptosis and cell cycle arrest.


Subject(s)
Antineoplastic Agents, Alkylating/administration & dosage , Diterpenes/administration & dosage , Lung Neoplasms/drug therapy , Phenanthrenes/administration & dosage , RNA, Ribosomal/metabolism , Signal Transduction/drug effects , A549 Cells , Animals , Antineoplastic Agents, Alkylating/pharmacology , Cell Cycle Checkpoints/drug effects , Cell Proliferation/drug effects , Cell Survival/drug effects , Diterpenes/pharmacology , Epoxy Compounds/administration & dosage , Epoxy Compounds/pharmacology , Gene Expression Regulation, Neoplastic/drug effects , Humans , Lung Neoplasms/metabolism , Male , Mice , Phenanthrenes/pharmacology , Proto-Oncogene Proteins c-mdm2/metabolism , Ribosomal Proteins/metabolism , Tumor Suppressor Protein p53/metabolism , Xenograft Model Antitumor Assays
6.
Patient Prefer Adherence ; 11: 1533-1539, 2017.
Article in English | MEDLINE | ID: mdl-28979101

ABSTRACT

BACKGROUND: Anticoagulation is the therapeutic paradigm for stroke prevention in patients with atrial fibrillation (AF). It is unknown how physicians make treatment decisions in primary stroke prevention for patients with AF. OBJECTIVES: To evaluate the association between family physicians' risk preferences (aversion risk and ambiguity) and therapeutic recommendations (anticoagulation) in the management of AF for primary stroke prevention by applying concepts from behavioral economics. METHODS: Overall, 73 family physicians participated and completed the study. Our study comprised seven simulated case vignettes, three behavioral experiments, and two validated surveys. Behavioral experiments and surveys incorporated an economic framework to determine risk preferences and biases (e.g., ambiguity aversion, willingness to take risks). The primary outcome was making the correct decision of anticoagulation therapy. Secondary outcomes included medical errors in the management of AF for stroke prevention. RESULTS: Overall, 23.3% (17/73) of the family physicians elected not to escalate the therapy from antiplatelets to anticoagulation when recommended by best practice guidelines. A total of 67.1% of physicians selected the correct therapeutic options in two or more of the three simulated case vignettes. Multivariate analysis showed that aversion to ambiguity was associated with appropriate change to anticoagulation therapy in the management of AF (OR 5.48, 95% CI 1.08-27.85). Physicians' willingness to take individual risk in multiple domains was associated with lower errors (OR 0.16, 95% CI 0.03-0.86). CONCLUSION: Physicians' aversion to ambiguity and willingness to take risks are associated with appropriate therapeutic decisions in the management of AF for primary stroke prevention. Further large scale studies are needed.

7.
Cancer Res ; 77(13): 3591-3604, 2017 07 01.
Article in English | MEDLINE | ID: mdl-28484077

ABSTRACT

Chronic inflammation induced by persistent microbial infection plays an essential role in tumor progression. Although it is well documented that Epstein-Barr virus (EBV) infection is closely associated with nasopharyngeal carcinoma (NPC), how EBV-induced inflammation promotes NPC progression remains largely unknown. Here, we report that tumor infiltration of tumor-associated macrophages (TAM) and expression of CCL18, the cytokine preferentially secreted by TAM, closely correlate with serum EBV infection titers and tumor progression in two cohorts of NPC patients. In vitro, compared with EBV- NPC cell lines, EBV+ NPC cell lines exhibited superior capacity to attract monocytes and skew them to differentiate to a TAM-like phenotype. Cytokine profiling analysis revealed that NPC cells with active EBV replications recruited monocytes by VEGF and induced TAM by GM-CSF in an NF-κB-dependent manner. Reciprocally, TAM induced epithelial-mesenchymal transition and furthered NF-κB activation of tumor cells by CCL18. In humanized mice, NPC cells with active EBV replications exhibited increased metastasis, and neutralization of CCL18, GM-CSF, and VEGF significantly reduced metastasis. Collectively, our work defines a feed-forward loop between tumor cells and macrophages in NPC, which shows how metastatic potential can evolve concurrently with virus-induced chronic inflammation. Cancer Res; 77(13); 3591-604. ©2017 AACR.


Subject(s)
Carcinoma/virology , Epstein-Barr Virus Infections/immunology , Granulocyte-Macrophage Colony-Stimulating Factor/immunology , Macrophages/immunology , Nasopharyngeal Neoplasms/virology , Vascular Endothelial Growth Factor A/immunology , Animals , Carcinoma/genetics , Carcinoma/metabolism , Carcinoma/pathology , Cell Line, Tumor , Disease Progression , Epstein-Barr Virus Infections/genetics , Epstein-Barr Virus Infections/metabolism , Epstein-Barr Virus Infections/pathology , Granulocyte-Macrophage Colony-Stimulating Factor/biosynthesis , Heterografts , Humans , Macrophage Activation/immunology , Macrophages/metabolism , Macrophages/pathology , Macrophages/virology , Mice , Mice, Inbred NOD , Mice, SCID , Middle Aged , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms/genetics , Nasopharyngeal Neoplasms/metabolism , Nasopharyngeal Neoplasms/pathology , Neoplasm Metastasis , Signal Transduction , Vascular Endothelial Growth Factor A/biosynthesis
8.
DNA Cell Biol ; 35(10): 622-627, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27383136

ABSTRACT

Drug resistance is an obstacle in the chemotherapeutic treatment of lung cancers. In the present study, the effects of high-mobility group box 1 (HMGB1) protein in chemotherapeutic resistance and the relationships between HMGB1 and chemotherapy drug-induced cell apoptosis or necrosis were clarified. We used cisplatin-sensitive A549 cells and cisplatin-resistant A549/DDP cells as cell models with IC50 of 11.58 and 46.95 µM, respectively. A549/DDP had higher level of HMGB1 compared with A549 cells. Interestingly, with the increasing concentration of DDP, HMGB1 was gradually located into cytoplasm in cisplatin-sensitive A549 cells. Moreover, interference with endogenous HMGB1 sensitized the effects of chemotherapeutic drugs, including 5-Fu, DDP, and OXA. Furthermore, results from an in vivo tumorigenesis experiment demonstrated that serum concentration of HMGB1 was much lower in the group inoculated with HMGB1 shRNA-transfected A549 cells than in the N.C. shRNA-transfected A549 inoculated group, as well as the tumor volume, suggesting that serum HMGB1 contributed to tumor growth in a mouse model. In conclusion, higher levels of HMGB1 probably contributed to chemotherapy drug resistance, and higher serum concentration of HMGB1 promoted in vivo tumor growth. The study would provide new clues to overcome drug resistance in chemotherapy of human lung cancers.


Subject(s)
Antineoplastic Agents/administration & dosage , Cisplatin/administration & dosage , Drug Resistance, Neoplasm , HMGB1 Protein/metabolism , Lung Neoplasms/drug therapy , A549 Cells , Animals , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Cisplatin/pharmacology , Gene Knockdown Techniques , HMGB1 Protein/genetics , Humans , Mice , Mice, Inbred BALB C , Mice, Nude
9.
Oncotarget ; 6(33): 34758-73, 2015 Oct 27.
Article in English | MEDLINE | ID: mdl-26416449

ABSTRACT

The infiltration of tumor-associated macrophages (TAMs) is associated with extensive angiogenesis, which contributes to a poor prognosis in breast cancer. However, anti-angiogenic therapy with VEGF-specific monotherapy has been unsuccessful in treating breast cancer, and the molecular mechanisms associated with chemoresistance remain unclear. Here, we investigated whether CCL18, a chemokine produced by TAMs, can stimulate angiogenesis in breast cancer, as well as the underlying mechanisms. Double immunohistochemical staining for CCL18 and CD34/CD31/vWF was performed in 80 breast cancer samples to study the correlation between CCL18+ TAMs and microvascular density (MVD). Cocultures of TAMs with human umbilical vein endothelial cells (HUVECs) were used to model the inflammatory microenvironment, and CCL18-induced angiogenesis was evaluated both in vitro and in vivo. We demonstrated that CCL18+ TAM infiltration positively associated with MVD in breast cancer samples, which was correlated with tumor metastasis and poor prognosis. We confirmed, both in vitro and in vivo, that CCL18 and VEGF synergistically promoted endothelial cell migration and angiogenesis. Conversely, blocking CCL18 or VEGF with neutralizing antibodies synergistically inhibited the promigratory effects of TAMs. Silencing PITPNM3, a putative CCL18 receptor, on the surface of HUVECs abrogated CCL18-mediated promigration and the enhancement of HUVEC tube formation, independently of VEGFR signaling. Moreover, CCL18 exposure induced the endothelial-mesenchymal transformation and activated ERK and Akt/GSK-3ß/Snail signaling in HUVECs, thereby contributing to its pro-angiogenic effects. In conclusion, our findings suggest that CCL18 released from TAMs promotes angiogenesis and tumor progression in breast cancer; thus, CCL18 may serve as a novel target for anti-angiogenic therapies.


Subject(s)
Breast Neoplasms/blood supply , Carcinoma, Ductal, Breast/blood supply , Chemokines, CC/metabolism , Macrophages/metabolism , Neovascularization, Pathologic/metabolism , Tumor Microenvironment/physiology , Animals , Blotting, Western , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/metabolism , Carcinoma, Ductal, Breast/pathology , Enzyme-Linked Immunosorbent Assay , Female , Flow Cytometry , Fluorescent Antibody Technique , Heterografts , Humans , Immunohistochemistry , Mice , Mice, Inbred NOD , Mice, SCID , RNA, Small Interfering , Transfection , Vascular Endothelial Growth Factor A/metabolism
10.
World J Gastroenterol ; 19(30): 4867-76, 2013 Aug 14.
Article in English | MEDLINE | ID: mdl-23946591

ABSTRACT

Hepatitis B virus (HBV) infection is a global public health problem that causes persistent liver diseases such as chronic hepatitis, cirrhosis, and hepatocellular carcinoma. A large amount of people die annually from HBV infection. However, the pathogenesises of the HBV-related diseases are ill defined and the therapeutic strategies for the diseases are less than optimum. The recently discovered microRNAs (miRNAs) are tiny noncoding RNAs that regulate gene expression primarily at the post-transcriptional level by binding to mRNAs. miRNAs contribute to a variety of physiological and pathological processes. A number of miRNAs have been found to play a pivotal role in the host-virus interaction including host-HBV interaction. Numerous studies have indicated that HBV infection could change the cellular miRNA expression patterns and different stages of HBV associated disease have displayed distinctive miRNA profiles. Furthermore, the differential expressed miRNAs have been found involved in the progression of HBV-related diseases, for instance some miRNAs are involved in liver tumorigenesis and tumor metastasis. Studies have also shown that the circulating miRNA in serum or plasma might be a very useful biomarker for the diagnosis and prognosis of HBV-related diseases. In addition, miRNA-based therapy strategies have attracted increasing attention, indicating a promising future in the treatment of HBV-related diseases.


Subject(s)
Hepatitis B virus/pathogenicity , Hepatitis B, Chronic/genetics , MicroRNAs/metabolism , Animals , Disease Progression , Gene Expression Regulation , Genetic Markers , Genetic Therapy , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/therapy , Hepatitis B, Chronic/virology , Host-Pathogen Interactions , Humans , MicroRNAs/therapeutic use
11.
Zhonghua Yi Xue Za Zhi ; 93(8): 603-5, 2013 Feb 26.
Article in Chinese | MEDLINE | ID: mdl-23663342

ABSTRACT

OBJECTIVE: To evaluate the diagnostic utility of bronchoscopy in solid organ transplant recipients with pulmonary opportunistic infections. METHODS: From December 2006 to September 2011, 117 cases of bronchoscopy with protected specimen brush and bronchoalveolar lavage were performed in 114 solid organ transplant recipients at Tianjin First Central Hospital. The indication for bronchoscopy was suspected pulmonary infections. The bronchoscopic manifestations were described and the specimens analyzed with regards to bacteriology, cytomegalovirus, P carinii, mycobacterium tuberculosis and other fungal cultures. RESULTS: A definite infectious etiology was confirmed in 63 patients (53.8%). And opportunistic infections were the most frequent etiology (56/63, 88.9% including 7 cases with two mixed opportunistic infections). Among 63 pathogens, P carinii was demonstrated in 36 episodes, cytomegalovirus in 24 episodes and mycobacterium tuberculosis in 3 episodes. Bacterial infections (mainly Gram-negative) accounted for 16 of 63 episodes (25.9% including 9 cases with mixed opportunistic/bacterial infection). In accordance with the diagnostic results, antibiotic treatment was changed in 45 cases. CONCLUSIONS: As an extremely useful tool, bronchoscopy is of great value for pathogenic detection in transplant recipients with suspected pulmonary infections, especially for opportunistic infections. And the bronchoscopic findings may guide targeted antimicrobial therapy.


Subject(s)
Bronchoscopy , Opportunistic Infections/diagnosis , Pneumonia, Pneumocystis/diagnosis , Pneumonia, Viral/diagnosis , Adult , Aged , Female , Humans , Male , Middle Aged , Opportunistic Infections/etiology , Organ Transplantation/adverse effects , Pneumonia, Pneumocystis/etiology , Pneumonia, Pneumocystis/microbiology , Pneumonia, Viral/etiology , Pneumonia, Viral/virology
12.
Sci Transl Med ; 4(130): 130ra48, 2012 Apr 18.
Article in English | MEDLINE | ID: mdl-22517885

ABSTRACT

A major obstacle to developing small interfering RNAs (siRNAs) as cancer drugs is their intracellular delivery to disseminated cancer cells. Fusion proteins of single-chain fragmented antibodies (ScFvs) and positively charged peptides deliver siRNAs into specific target cells. However, the therapeutic potential of ScFv-mediated siRNA delivery has not been evaluated in cancer. Here, we tested whether Polo-like kinase 1 (PLK1) siRNAs complexed with a Her2-ScFv-protamine peptide fusion protein (F5-P) could suppress Her2(+) breast cancer cell lines and primary human cancers in orthotopic breast cancer models. PLK1-siRNAs transferred by F5-P inhibited target gene expression, reduced proliferation, and induced apoptosis of Her2(+) breast cancer cell lines and primary human cancer cells in vitro without triggering an interferon response. Intravenously injected F5-P/PLK1-siRNA complexes concentrated in orthotopic Her2(+) breast cancer xenografts and persisted for at least 72 hours, leading to suppressed PLK1 gene expression and tumor cell apoptosis. The intravenously injected siRNA complexes retarded Her2(+) breast tumor growth, reduced metastasis, and prolonged survival without evident toxicity. F5-P-mediated delivery of a cocktail of PLK1, CCND1, and AKT siRNAs was more effective than an equivalent dose of PLK1-siRNAs alone. These data suggest that F5-P could be used to deliver siRNAs to treat Her2(+) breast cancer.


Subject(s)
Breast Neoplasms/metabolism , Breast Neoplasms/therapy , Cell Cycle Proteins/genetics , Protein Serine-Threonine Kinases/genetics , Proto-Oncogene Proteins/genetics , Receptor, ErbB-2/metabolism , Animals , Apoptosis/genetics , Apoptosis/physiology , Cell Line, Tumor , Cell Proliferation , Female , Humans , Mice , RNA, Small Interfering/genetics , RNA, Small Interfering/physiology , Single-Chain Antibodies/administration & dosage , Single-Chain Antibodies/genetics , Tumor Cells, Cultured , Xenograft Model Antitumor Assays , Polo-Like Kinase 1
13.
Environ Pollut ; 157(11): 3150-7, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19520467

ABSTRACT

Biodegradation of dissolved fluorene (Flu), phenanthrene (Ph) and pyrene (Py), three polycyclic aromatic hydrocarbons (PAHs), singly or as a mixture of the three, by two bacterial strains, MEBIC 5140 (Mycobacterium flavescens) and MEBIC 5141 (Mycobacterium scrofulaceum), as well as the effects of low molecular weight organic acids (LMWOAs), e.g. malic acid, citric acid and butyric acid on biodegradation of the three PAHs in mineral salts medium aqueous solution were investigated using a newly established dual-wavelength fluorimetric method. The results showed that biodegradation processes can be monitored simultaneously, quickly and simply by dual-wavelength fluorimetry. Both co-metabolism and inhibitory effects were found during the biodegradation of the three PAHs by MEBIC 5140 and MEBIC 5141. Positive effects of butyric acid and negative effects of citric acid on biodegradation of the three PAHs in a mixture were observed.


Subject(s)
Acids/metabolism , Fluorometry/methods , Mycobacterium/metabolism , Polycyclic Aromatic Hydrocarbons/metabolism , Acids/chemistry , Biodegradation, Environmental , Fluorometry/instrumentation , Molecular Weight , Solutions/chemistry
14.
Talanta ; 78(4-5): 1339-44, 2009 Jun 15.
Article in English | MEDLINE | ID: mdl-19362198

ABSTRACT

A fluorimetric method for simultaneous determination of dissolved acenaphthylene (Ace) phenanthrene (Ph) and pyrene (Py), mixed in an aqueous mineral salts medium (MSM), was developed. The linear ranges for determination of Ace, Ph and Py dissolved in the mixture were 4.00 x 10(-6) to 3.00 x 10(-3)g/L, 2.00 x 10(-6) to 1.00 x 10(-3)g/L and 7.00 x 10(-7) to 1.00 x 10(-4)g/L. The limits of detection for Ace, Ph and Py were 8.53 x 10(-7), 4.98 x 10(-7) and 6.01 x 10(-8)g/L and the relative standard deviations 1.05%, 1.62% and 1.16% (n=8), respectively. Satisfactory results were obtained when this method was used to simultaneously study the biodegradation processes of mixtures of dissolved Ace, Ph and Py in an MSM aqueous solution.


Subject(s)
Biodegradation, Environmental , Fluorometry/methods , Mycobacterium/metabolism , Polycyclic Aromatic Hydrocarbons/metabolism , Acenaphthenes/analysis , Acenaphthenes/metabolism , Kinetics , Phenanthrenes/analysis , Phenanthrenes/metabolism , Polycyclic Aromatic Hydrocarbons/analysis , Pyrenes/analysis , Pyrenes/metabolism
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