[Characteristics, Ecological Risk Assessment, and Source Apportionment of Soil Heavy Metals in the Yellow River Floodplain of Yinchuan City].

In order to study the status and sources of heavy metal pollution in Yinchuan Yellow River floodplain soils, we used inductively coupled plasma mass spectrometry (ICP-MS) to determine the presence of eight heavy metals in 92 soil samples from the Yinchuan Yellow River floodplain and used enrichment factors, geological accumulation index, and potential ecological risk index to analyze and evaluate the characteristics of heavy metal pollution in the study area. Combined correlation analysis, absolute factor analysis-multiple linear regression model (APCS-MLR), positive matrix factorization (PMF), and geostatistics were used to analyze the sources of soil heavy metals. The results showed that the content of eight heavy metals in the surface soil of the Yellow River floodplain in Yinchuan City were lower than the screening value of soil pollution risk in agricultural land; Cu and Pb contents were lower than the background value of Yinchuan City soil, and the contents of the remaining six elements were higher than the background value. The coefficients of variation of Zn and Cd were large and in the medium variation level and were influenced by anthropogenic activities. The heavy metal content varied between different land types and generally showed that wasteland > abandoned farmland > woodland > cultivated land. The average content of Cu and Pb in forest and arable soils was lower than the regional background value, whereas the rest of the heavy metals in different land types were higher than the soil background value. The analysis of enrichment factors showed that Zn and Cd were slightly enriched in the study area, and the cumulative index method and the evaluation of the potential risk of single heavy metals indicated that more than 60% of the sites in the study area were contaminated with Cd at a medium or higher potential ecological hazard. The comprehensive evaluation results of potential ecological risk showed that the overall ecological risk level of the study area was mild. From the distribution of heavy metal ecological risk comprehensive index sample points, only one point was in moderate ecological hazard, and the pollution point showed very few. Comprehensive correlation analysis, APCS-MLR model, PMF model, and geostatistical analysis results confirmed that Zn and Cd in the study area were mainly derived from human activities such as agricultural activities and transportation, and the remaining heavy metals were derived from soil parent materials. The results of this study can provide a scientific basis for the ecological protection and sustainable development of the Yellow River in Yinchuan City.

Clinical factors affecting the long-term survival of breast cancer patients.

OBJECTIVE: The average 5-year survival rate of breast cancer (BC) patients has been significantly prolonged with new therapeutic methods. However, their effects on BC patient long-term survival rates are unclear. Therefore, this study aimed to analyze the specific clinical factors that can affect BC long-term survival. METHODS: Here, we conducted a retrospective study and analyzed long-term survival using data of 3,240 BC patients from 1977 to 2005 from the Genotype-Tissue Expression (GTEx) database using the Kaplan-Meier method. RESULTS: Breast tumor size and stage were negatively correlated with long-term survival, but age showed no significant correlation. Estrogen receptor (ER) and progesterone receptor (PR) expression were each positively correlated with patient survival time, while ERBB2 receptor (HER2) expression was negatively correlated with survival time. Patients with high Nottingham prognostic index (NPI) values did not benefit from available therapies. Furthermore, breast-conserving surgery is more conducive to BC patient long-term survival than mastectomy. CONCLUSIONS: Early detection and breast-conserving surgery may support long-term survival for BC patients. Elevated expression of ER and PR were both associated with longer patient survival time, while positive expression of HER2 showed the opposite trend. The long-term survival rates of patients with high NPI values can potentially be increased.

miR-381-3p suppresses breast cancer progression by inhibition of epithelial-mesenchymal transition.

BACKGROUND: Accumulating evidence indicates that miRNAs are involved in multiple cellular functions and participate in various cancer development and progression, including breast cancer. METHODS: We aimed to investigate the role of miR-381-3p in breast cancer. The expression level of miR-381-3p and EMT transcription factors was examined by quantitative real-time PCR (qRT-PCR). The effects of miR-381-3p on breast cancer proliferation and invasion were determined by Cell Counting Kit-8 (CCK-8), colony formation, and transwell assays. The regulation of miR-381-3p on its targets was determined by dual-luciferase analysis, qRT-PCR, and western blot. RESULTS: We found that the expression of miR-381-3p was significantly decreased in breast cancer tissues and cell lines. Overexpression of miR-381-3p inhibited breast cancer proliferation and invasion, whereas knockdown of miR-381-3p promoted cell proliferation and invasion in MDA-MB-231 and SKBR3 cells. Mechanistically, overexpression of miR-381-3p inhibited breast cancer epithelial-mesenchymal transition (EMT). Both Sox4 and Twist1 were confirmed as targets of miR-381-3p. Moreover, transforming growth factor-ß (TGF-ß) could reverse the effects of miR-381-3p on breast cancer progression. CONCLUSIONS: Our observation suggests that miR-381-3p inhibits breast cancer progression and EMT by regulating the TGF-ß signaling via targeting Sox4 and Twist1.

MicroRNA­454­5p promotes breast cancer progression by inducing epithelial­mesenchymal transition via targeting the FoxJ2/E­cadherin axis.

MicroRNAs are important for the regulation of multiple cellular functions and are involved in the initiation and progression of various types of cancer, including breast cancer. Although microRNA (miR)­454­3p is reported to function as an oncogene in several types of human cancer, the role of miR­454­5p in breast cancer remains unknown. The present study demonstrated that miR­454­5p was upregulated in breast cancer and was associated with a poor prognosis in patients with breast cancer. Overexpression of miR­454­5p promoted breast cancer cell viability, migration and invasion in vitro, whereas silencing of miR­454­5p inhibited breast cancer proliferation, migration and invasion in vitro and suppressed tumor growth in vivo. Mechanistically, forkhead box J2 (FoxJ2) was shown to be a target of miR­454­5p and transactivated E­cadherin expression. Moreover, silencing of miR­454­5p reversed the epithelial­mesenchymal transition phenotype through upregulation of the FoxJ2/E­cadherin axis. Collectively, the present findings suggested that miR­454­5p may serve as a novel therapeutic target and prognostic predictor for patients with breast cancer.

Analysis of risk factors and establishment of a risk prediction model for cardiothoracic surgical intensive care unit readmission after heart valve surgery in China: A single-center study.

BACKGROUND: Valvular heart disease is one of the most frequent and challenging heart diseases worldwide. The incidence of complications and cardiothoracic surgical intensive care unit (CSICU) readmission after cardiac valve surgery is high. Because CSICU readmission is costly and adversely impacts the quality life, reducing the risk of CSICU readmission has become one of the main focuses of health care. OBJECTIVE: To explore the risk factors for CSICU readmission and to establish a risk prediction model for CSICU readmission in heart valve surgical patients. METHODS: A total of 1216 patients who had undergone cardiac valvular surgery between January 2016 and August 2017 at the First Affiliated Hospital of Sun Yat-sen University were assigned as the development and validation data sets. Data from 824 patients in the development data set were retrospectively analyzed to identify potential risk factors with univariate analysis. Multivariate logistic regression was used to determine the independent risk factors of CSICU readmission, which served as the basis for our prediction model. The calibration and discrimination of the model were assessed by the Hosmer-Lemeshow (H-L) test and the area under the receiver operating characteristic (ROC) curve, respectively. RESULTS: Six preoperative variables (age ≥ 65, previous chronic lung disease, prior cardiac surgery, left ventricular ejection fraction (LVEF) ≤ 40%, 40% < LVEF ≤ 50%, and New York Heart Association (NYHA) classification III/IV), two intraoperative variables (multiple valve repair/replacement and cardiopulmonary bypass time ≥ 180 min), and five postoperative variables (cardiac arrest, acute respiratory distress syndrome, pneumonia, deep sternal wound infection, and renal failure) were independent risk factors of CSICU readmission. Our risk prediction model, which was established based on the above-mentioned risk factors, had robust discrimination and calibration in both the development and validation data sets. CONCLUSION: The prediction model established in our study is a simple, objective, and accurate scoring system, which can be used to predict the risk of CSICU readmission and assist researchers with designing intervention strategies to prevent CSICU readmission.

Activation of CD137 Signaling Enhances Vascular Calcification through c-Jun N-Terminal Kinase-Dependent Disruption of Autophagic Flux.

BACKGROUND: Vascular calcification is widespread and clinically significant, contributing to substantial morbidity and mortality. Calcifying vascular cells are partly derived from local vascular smooth muscle cells (VSMCs), which can undergo chondrogenic or osteogenic differentiation under inflammatory environment. Recently, we have found activation of CD137 signaling accelerated vascular calcification. However, the underlying mechanism remains unknown. This study aims to identify key mediators involved in CD137 signaling-induced vascular calcification in vivo and in vitro. METHODS: Autophagy flux was measured through mRFP-GFP-LC3 adenovirus and transmission electron microscopy. Von Kossa assay and alkaline phosphatase (ALP) activity were used to observe calcification in vivo and in vitro, respectively. Autophagosome-containing vesicles were collected and identified by flow cytometry and Western blot. Autophagy or calcification-associated targets were measured by Western blot, quantitative real-time PCR, and immunohistochemistry. RESULTS: Treatment with the agonist-CD137 displayed c-Jun N-terminal kinase- (JNK-) dependent increase in the expression of various markers of autophagy and the number of autophagosomes relative to the control group. Autophagy flux experiments suggested that agonist-CD137 blocked the fusion of autophagosomes with lysosomes in cultured VSMCs. Calcium deposition, ALP activity, and the expression of calcification-associated proteins also increased in agonist-CD137 group compared with anti-CD137 group, which could be recovered by autophagy stimulator rapamycin. Autophagosome-containing vesicles collected from agonist-CD137 VSMCs supernatant promoted VSMC calcification. CONCLUSION: The present study identified a new pathway in which CD137 promotes VSMC calcification through the activation of JNK signaling, subsequently leading to the disruption of autophagic flux, which is responsible for CD137-induced acceleration of vascular calcification.

Amelioration of Inflammatory Cytokines Mix Stimulation: A Pretreatment of CD137 Signaling Study on VSMC.

Previous studies showed little CD137 expressed in normal vascular smooth muscle cells (VSMCs) and it is important to find a valid way to elevate it before studying its function. The level of CD137 was detected by RT-PCR, western blot, and flow cytometry, respectively. CD137 signaling activation was activated by agonist antibody and measured through phenotype transformation indicators and cell functions. Proteins in supernatants were detected by ELISA. The total CD137 elevates under different concentrations of CM treatment. Among these, 25 ng/ml CM treatment increases the CD137 expression mostly. However, flow cytometry demonstrates that 10 ng/ml CM elevates surface CD137 more significantly than other concentrations and reaches the peak at 36 h. At 10 ng/ml, but not 25 ng/ml CM pretreatment, the levels of phenotype related proteins such as SM-MHC, α-SMA, and calponin decrease while vimentin and NFATc1 increase, suggesting that VSMCs undergo phenotype transformation. Transwell, CCK-8 assay, and ELISA showed that the ability of VSMCs viability, migration, and IL-2 and IL-6 secretion induced by CD137 signaling was significantly enhanced by the pretreatment of 10 ng/ml CM. This research suggested that 10 ng/ml CM pretreatment is more reasonable than other concentrations when exploring CD137 function in VSMCs.

A new cooperative approach for ST-elevation myocardial infarction patients to receive timely and effective percutaneous coronary reperfusion in China.

BACKGROUND: Acute myocardial infarction (AMI) is the most serious type of coronary heart disease. However, less than 30% of these patients have been treated effectively in China. Delayed treatment is a leading cause. This study aimed to evaluate a new regional cooperative model for improving the first medical contact-to-device time and the therapeutic effects on AMI patients. METHODS: A retrospective analysis of 458 ST-elevation myocardial infarction (STEMI) patients was performed. Patients were divided into two groups in terms of before or after the model were implemented. First medical contact-to-device time (FMC2D), Door to device time (D2D), referral time, cardiac functions, mean cost, days of hospitalization, and major adverse cardiac events (MACE) were analyzed. RESULTS: The mean FMC2D time, D2D time and referral time of the model group were significantly lower than the control group. The left ventricular ejection fraction of the model group increased but the left ventricular end-diastolic dimension decreased compared with the control group at 6 months after discharge. These results also showed that mean costs and days of hospitalization were reduced. The MACE rate was reduced in the model group. CONCLUSIONS: These results suggested that the new model decreased the FMC2D time, which could improve the cardiac function and therapeutic effect of STEMI patients as well as decreased the financial burden.

Influence of microstructural features on thermal expansion coefficient in graphene/epoxy composites.

In this paper, theoretical calculations were conducted to determine the coefficient of thermal expansion (CTE) based on the effective medium approach using Green's function method. The influences of microstructural features were investigated, including volume fraction, aspect ratio, and the orientation of graphene fillers. Calculated results demonstrated strong anisotropy of CTE when all graphene sheets in the composite were aligned in the in-plane direction due to the large difference between the elastic moduli of the graphene and epoxy. The in-plane CTE in the graphene/epoxy composite can be effectively reduced with small additions of graphene additive. Orientation dispersion among the graphene fillers significantly decreases the anisotropy of CTE. Accounting for the influences of all microstructural features, simulation results closely align with current experimental results. This work will provide a general guideline and a solid foundation for the optimal design and preparation of graphene/polymer composites.

[Degradation of the Nitrogenous Heterocyclic Compound Quinoline by O3/UV].

The influences of various factors including initial concentration of quionline solution, static duration after reaction, initial pH, HCO3-on the degradation of quinoline by O3/UV were analyzed in this study. In addition, the degradation mechanism and pathways were also analyzed. The results showed that reaction rate constants and removal rate of quinoline decreased with the increase of the initial concentration of quinoline. The best degradation efficiency of quinoline was achieved under the alkaline conditions (pH 7-9). Removal rate of quinoline was obviously influenced by HCO3-, and was reduced by 42.01% within 6 min when the concentration of HCO3- was 100 mg·L-1. There was neglected effect of static duration after reaction on the removal rate and mineralization rate of quinolone. The intermediate products of quinoline were mainly 8-hydroxyquinoline, 5-hydroxyquinoline, 2(1H)-quinoline ketone, 2-pyridinecarboxaldehyde and so on. The main degradation pathways of quinoline in the O3/UV system were addition reaction, substitution reaction and electrophilic substitution mediated by O3 and·OH.

High density lipoprotein from patients with valvular heart disease uncouples endothelial nitric oxide synthase.

Normal high density lipoprotein (HDL) protects vascular function; however these protective effects of HDL may absent in valvular heart disease (VHD). Because vascular function plays an important role in maintaining the circulation post-cardiac surgery and some patients are difficult to stabilize, we hypothesized that a deleterious vascular effect of HDL may contribute to vascular dysfunction in VHD patients following surgery. HDL was isolated from age-match 28 healthy subjects and 84 patients with VHD and during cardiac surgery. HDL pro-inflammation index was measured and the effects of HDL on vasodilation, protein interaction, generation of nitric oxide (NO) and superoxide were determined. Patients with VHD received either simvastatin (20mg/d) or routine medications, and endothelial effects of HDL were characterized. HDL inflammation index significantly increased in VHD patients and post-cardiac surgery. HDL from VHD patients and post-cardiac surgery significantly impaired endothelium-dependent vasodilation, inhibited both Akt and endothelial nitric oxide synthase (eNOS) phosphorylation at S1177, eNOS associated with heat shock protein 90 (HSP90), NO production and increased eNOS phosphorylation at T495 and superoxide generation. Simvastatin therapy partially reduced HDL inflammation index, improved the capacity of HDL to stimulate eNOS and Akt phosphorylation at S1177, eNOS associated with HSP90, NO production, reduced eNOS phosphorylation at T495 and superoxide generation, and improved endothelium-dependent vasodilation. Our data demonstrated that HDL from VHD patients and cardiac surgery contributed to endothelial dysfunction through uncoupling of eNOS. This deleterious effect can be reversed by simvastatin, which improves the vasoprotective effects of HDL. Targeting HDL may be a therapeutic strategy for maintaining vascular function and improving the outcomes post-cardiac surgery.

Aerobic degradation of trichloroethylene by co-metabolism using phenol and gasoline as growth substrates.

Trichloroethylene (TCE) is a common groundwater contaminant of toxic and carcinogenic concern. Aerobic co-metabolic processes are the predominant pathways for TCE complete degradation. In this study, Pseudomonas fluorescens was studied as the active microorganism to degrade TCE under aerobic condition by co-metabolic degradation using phenol and gasoline as growth substrates. Operating conditions influencing TCE degradation efficiency were optimized. TCE co-metabolic degradation rate reached the maximum of 80% under the optimized conditions of degradation time of 3 days, initial OD600 of microorganism culture of 0.14 (1.26×107 cell/mL), initial phenol concentration of 100 mg/L, initial TCE concentration of 0.1 mg/L, pH of 6.0, and salinity of 0.1%. The modified transformation capacity and transformation yield were 20 µg (TCE)/mg (biomass) and 5.1 µg (TCE)/mg (phenol), respectively. Addition of nutrient broth promoted TCE degradation with phenol as growth substrate. It was revealed that catechol 1,2-dioxygenase played an important role in TCE co-metabolism. The dechlorination of TCE was complete, and less chlorinated products were not detected at the end of the experiment. TCE could also be co-metabolized in the presence of gasoline; however, the degradation rate was not high (28%). When phenol was introduced into the system of TCE and gasoline, TCE and gasoline could be removed at substantial rates (up to 59% and 69%, respectively). This study provides a promising approach for the removal of combined pollution of TCE and gasoline.

Effects of OX40-OX40L interaction on the nuclear factor of activated T cells c1 in ApoE-deficient mice.

We previously reported the emerging role of OX40-OX40L interaction in inflammation and atherosclerosis. However, the mechanism by which OX40-OX40L interaction contributes to pathogenesis is poorly understood. This study investigated the effects of OX40-OX40L interaction on the nuclear factor of activated T cells c1 (NFATc1) in ApoE(-/-) mice. Atherosclerotic plaque was induced via rapid perivascular carotid collar placement in ApoE(-/-) mice. The expression levels of OX40, OX40L, and NFATc1 in the lymphocytes were measured via real-time polymerase chain reaction and flow cytometry. The presence of NFATc1 in the atherosclerotic plaque was detected via immunohistochemistry, and the level of IL-4 was measured via enzyme-linked immunosorbent assay. The expression level of NFATc1 significantly increased in atherosclerotic lesion and in the leukocytes from the ApoE(-/-) mice. After stimulating OX40-OX40L interaction, the mRNA and protein expression levels of NFATc1 in the lymphocytes significantly increased. Meanwhile, anti-OX40LmAb significantly suppressed the expression of NFATc1 in the leukocytes and substantially elevated the level of IL-4. NFATc1 inhibitor markedly suppressed IL-4 production. This study suggests that OX40-OX40L interaction regulates the expression of NFATc1, which may play a critical role in atherosclerotic plaque formation, and may therefore have implications with pathophysiology of atherosclerosis.

[Bioremediation of PAHs contaminated soil from Beijing coking plant by Lasiodiplodia theobromae].

Bioremediation of PAHs contaminated soil from Beijing Coking Plant was performed using a novel fungal strain Lasiodiplodia theobromae (L. theobromae). Moreover, enhanced bioremediation of PAHs contaminated soil was investigated in the presence of different concentrations of Tween 80 and hydroxypropyl-beta-cyclodextrin (HPCD). The correlation of the dynamics of enzyme activities during remediation and the degradation of PAHs was analyzed. The results showed that the degradation rate of PAHs increased to 45.3% on the 70th day after addition of L. theobromae, which was 30 percentage points higher than that of the control group. At an optimum concentration of 2 g x kg(-1) for Tween 80 and 1 g x kg(-1) for HPCD, the degradation rate of PAHs was enhanced to 65.8% and 63.9%, respectively, which was 50 percentage points higher than that of the control group. Hydrogen peroxidase and invertase activities in soil in the bioremediation group with only L. theobromae and the surfactant enhanced group were both enhanced twice more than that of the control group. These results showed that L. theobromae may produce hydrogen peroxidase and invertase or have synergic effect with indigenous microorganisms. Correlation analysis showed that the correlation coefficients of PAHs degradation rate and maximum enzyme activities of hydrogen peroxidase and invertase were 0.781 and 0.837, respectively. Therefore, the correlation between invertase activities and degradation rate was higher.

[Effects of indocyanine green on near-infrared optical properties and optical coherence tomographic image of cerebral blood vessel in vivo in rats].

The scope of this research lies in the effects of indocyanine green (ICG) on the near-infrared optical properties and optical coherence tomographic image of cerebral blood vessel in vivo in rats. The skulls of SD rats were opened under nembutal anesthesia to expose and mark the middle cerebral artery. The reflectance spectra of middle cerebral artery were monitored by Vis/ NIR spectrometer and the optical attenuation coefficients of middle cerebral artery were detected by optical coherence tomography (OCT) when indocyanine green was administrated intravenously through tail veins. It was shown that the reflectance spectra of middle cerebral artery could provide guidance for OCT image, where characteristic changes appeared around 800 nm, an absorption peak of indocyanine green. Additionally, significant difference (p<0.01) was observed between the optical attenuation coefficients of middle cerebral artery with and without indocyanine green, which were 24.692 +/- 1.471 and 15.088 +/- 1.602, respectively. It was concluded that indocyanine green, as an optical contrast agent to enhance detection of cerebral artery by the reflectance spectra and OCT imaging, has the potential for monitoring and imaging of cerebral blood vessels.

2-(4-Fluoro-phen-yl)quinoxaline.

In the title compound, C(14)H(9)FN(2), the dihedral angle between the benzene ring and the quinoxaline ring system is 22.2 (3)°. Any aromatic π-π stacking in the crystal must be very weak, with a minimum centroid-centroid separation of 3.995 (2) Å.

Methyl 4-(5-meth-oxy-1H-indol-3-yl)benzoate.

In the title compound, C(17)H(15)NO(3), the dihedral angle between the benzene ring and the indole ring system is 22.5 (3)°. In the crystal, mol-ecules are linked by N-H⋯π and C-H⋯O inter-actions.

[Clinicopathologic features and expression of epidermal growth factor receptor and vascular endothelial growth factor in adrenocortical tumors].

OBJECTIVE: To study the clinicopathologic features and expression of epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) in adrenocortical tumors. METHODS: Forty-two cases of adrenocortical tumors operated at the Beijing Union Medical College Hospital during the period from July, 2001 to July, 2010 were retrospectively reviewed. Immunohistochemical study for EGFR and VEGF was carried out. The clinical information and follow-up data were analyzed. RESULTS: The cases included 21 adrenocortical carcinomas (ACC) and 21 adrenocortical adenomas (ACA). Nine patients suffered from primary aldosterone syndrome, including 8 cases with ACA and 1 case with ACC. The average tumor size, tumor weight, and duration between disease onset and diagnosis in the 21 cases of ACC were 11.7 cm, 542 g and 8.5 months, respectively. This was in contrast to 3 cm, 9.8 g and 45.6 months, respectively in cases of ACA. Histologically, the WEISS score in all the 21 cases of ACA was ≤ 2 (average = 0.9). None of the ACC cases had score less than 4 (average = 6.6). The presence of sinus invasion correlated with tumor metastasis (P < 0.01). Immunohistochemical study showed that EGFR was expressed in 61.9% of ACC patients (13/21), whereas EGFR staining was mostly negative in ACA (except for weak staining in 5 cases and moderate staining in 1 case). The difference of EGFR expression between ACC and ACA was statistically significant (P = 0.030). On the other hand, the positive rate of VEGF in ACC was 71.4% (15/21), including 28.6% (6/21) with strong expression and 28.6% (6/21) with moderate expression. In contrast, the expression rate of VEGF in ACA was 30.0% (7/21), including 14.3% (3/21) with moderate expression. The difference of VEGF expression between ACC and ACA was statistically significant (P = 0.013). There was correlation between VEGF expression and venous invasion (P = 0.028). The average duration of survival in patients with ACC was shorter than that in ACA. The tumor weight in ACC also correlated with prognosis. CONCLUSIONS: Tumor size, weight and presence of endocrine symptoms may help in the differential diagnosis between ACC and ACA. A WEISS score of ≥ 3 highly suggests ACC. The presence of sinus invasion is associated with metastasis. EGFR or VEGF expression may also be important in differentiating ACC from ACA.

[Isolation of highly-effective benzo[a]pyrene degrading strain and its degradation capacity].

One new mycete, which could degrade high concentration (up to 100 mg/L) of benzo[a]pyrene (BaP) in liquid, was isolated from contaminated soil of Beijing Coking Plant by gradually increasing the concentration of BaP in mineral salt medium (MSM) in order to get new microorganism species for remediation of BaP contamination. The strain was identified as Lasiodiplodia theobromae, and its biodegradation ability in liquid was further investigated. The results showed that L. theobromae could utilize BaP as sole carbon and energy sources. The experiment was conducted for 10 days, and the biodegradation rate of BaP was 52.5% +/- 1.5%. Compared to Czapek's mineral medium, MSM was more suitable for L. theobromae, and biodegradation rate was 2.8 percent greater than that by using Czapek's mineral media after 10 days' cultivation. Potato-dextrose nutrient medium could accelrate the biodegradation in early stage, and biodegradation rate of BaP increased by 19.2 percent in the second day. However, the accelration was not significant in the latter period, biodegradation rate was only increased by 5.4 percent after 10 days' cultivation. L. theobromae could tolerate a wide pH range, with the optimum pH of 5. Addition of salicylic and sodium succinate enhanced the biodegradation rates by 6.2 percent and 4.2 percent, respectively, after 10 days' cultivation. Besides BaP, L. theobromae could also degrade high concentration (200 mg/L) of phenanthrene and pyrene, and the biodegradation rates were 70.0% +/- 1.0%, 59.2% +/- 3.2%, and 52.5% +/- 1.5% when they were single substrate and were 21.6% +/- 2.1%, 14.5% +/- 5.5%, and 11.9% +/- 2.2% when they existed in mixture, respectively. The biodegradation rate followed an order of phenanthrene > pyrene > BaP. The co-existence of the three substrates led a reduction in biodegradation. This study provides a new microorganism species for remediation of polycyclic aromatic hydrocarbons (PAHs) contamination in the environment.