Differential photodegradation processes of adsorbed polychlorinated biphenyls on biochar colloids with various pyrolysis temperatures.

Despite the crucial role of photodegradation in the environmental transformation of organic pollutants, the photodegradation process of organic pollutants irreversibly absorbed on biochar colloids (BCCs) remains poorly understood. This study investigated the photodegradation processes and mechanisms of 2,4,4'-trichlorobiphenyl (PCB28) adsorbed on BCCs released from bulk biochars derived from bamboo chips at pyrolysis temperatures of 300, 500, and 700 °C. Results show that BCCs-adsorbed PCB28 could be degraded under simulated solar illumination (95-105 mW·cm-2) but at decreased photodegradation rates compared to the dissolved PCB28. The inhibition effect of BCCs on the PCB28 photodegradation increased with increasing pyrolysis temperature. After adsorptive binding to BCCs, the half-life of PCB28 (0.1 mg/L) was prolonged from 2.65 h for the dissolved PCB28 alone in deionized water to 7.48, 40.67, and 81.82 h in the presence of BCC300, BCC500, and BCC700 (5.0 mg/L), respectively. Mechanistically, the photodegradation of adsorbed pollutants was regulated by the photogenerated free radicals and surface functional groups of the low-temperature BCCs, as well as the defects and direct electron transfer capabilities of the high-temperature BCCs; PCB28 adsorbed on the low-temperature BCCs accepted electrons from persistent free radicals under light illumination, which led to PCB28 dechlorination, followed by ring-opening oxidation through hydroxyl radical attack, ultimately resulting in progressive mineralization; singlet oxygen caused preferential ring opening of adsorbed PCB28 on the high-temperature BCCs, preceding dechlorination. The photodegradation of BCCs-adsorbed PCB28 remained significant though more or less being inhibited under the effects of water pH, ionic strength, dissolved organic matters (humic acid and fulvic acid), and in natural water samples. These findings contribute to a better understanding of the structural properties of BCCs that impact phototransformation processes of adsorbed pollutants and facilitate an accurate assessment of the environmental risk associated with biochar application.

Adsorption and desorption of polychlorinated biphenyls on biochar colloids with different pyrolysis temperatures: the effect of solution chemistry.

Biochar releases colloidal particles into the environment during applications and aging which can become carriers of pollutants and influence on the environmental risk of pollutants due to the excellent adsorption and migration properties of biochar colloids (BCCs). The adsorption and desorption behaviors of BCCs can be different from their bulk ones due to the colloidal size, which merits specific studies. Herein, the adsorption and desorption of 2,4,4'-trichlorobiphenyl (PCB28) as a representative on BCCs released from bulk biochars prepared from bamboo chips at 300, 500, and 700 C and the effects of solution properties were specifically investigated. Results show that the adsorption was dominated by pore filling and π-π interaction, and thus, BCCs prepared at higher temperature with greater pore volume and aromaticity had higher adsorption of PCB28. Results show that the adsorption was dominated by pore filling and π-π interaction, and thus, BCCs prepared at higher temperature with greater pore volume and aromaticity had higher adsorption of PCB28. The saturation adsorption amounts of PCB28 on BCC300, BCC500, and BCC700 were 21.9, 40.3, and 62.4 mg/g, respectively. It is noteworthy that PCB28 possessed a significant desorption hysteresis from BCCs, with the hysteresis index (Ce = 80 µg/L) increased from 0.380 to 0.661 as the preparation temperature of BCCs rising from 300 to 700 â„ƒ. High concentration of NaCl (100 mmol/L) was unfavorable for the adsorption and desorption. The presence of humic acid or fulvic acid (FA), especially the smaller FA, could inhibit the adsorption and desorption of PCB28 on BCCs due to micropore blocking. In seawater, groundwater, surface water, and soil solution samples, the PCB28 adsorption of BCCs was inhibited to varying degrees in comparison with that in deionized water, and the desorption was noticeably inhibited in the groundwater sample. These findings provide valuable information for the understanding of interactions between BCCs and organic contaminants in natural waters and for the environmental application of biochars as well.

Identification of seven-gene signature for prediction of lung squamous cell carcinoma.

Background and aim: Lung squamous cell carcinoma (LUSC), is a pathological subtype of lung cancer, accounting for 30% of the lung cancers. A reliable model was constructed, based on the whole gene expression profiles, to predict the prognosis of patients with LUSC. Methods: The RNA-Seq data of LUSC was downloaded from the TCGA database, and differentially expressed genes (p<0.05, |log2fold change| >1) were screened out. By univariate and multivariate Cox regression analysis, we identified seven prognosis-related genes. Then, we established a risk score staging system to predict the prognosis of patients with LUSC. Compared with other clinical parameters, the risk score was an independent prognostic factor and had a better performance in predicting prognosis. Finally, GSEA analysis was carried out to determine the enrichment pathway significantly. The risk score models were established by Cox proportional hazard regression analysis; the ROC curve was applied to test the performance of risk score model. All the statistical analysis was accomplished by R packages. Results: In this study, a model was constructed to predict prognosis, which contains seven genes: CSRNP1, CLEC18B, MIR27A, AC130456.4, DEFA6, ARL14EPL, and ZFP42. Based on the model, the risk score of each patient was calculated with LUSC (hazard ratio [HR]=2.673, 95% CI=1.871-3.525). It was found that the risk score can distinguish high-risk and low-risk groups in prognosis of LUSC patients, independently. Furthermore, the model was validated by ROC curves in the testing dataset and the whole dataset. Lastly, by gene set enrichment analysis (GSEA), we showed the main enrichment pathways were DNA damage stimulus, DNA repair, and DNA replication. It was suggested that the risk score may provide a new and reliable method for prognosis prediction. Conclusion: The results of this study suggested that the risk score based on seven-genes could indicate a promising and independent prognostic biomarker for LUSC patients.

Circular RNA PVT1 promotes metastasis via miR-145 sponging in CRC.

Circular RNAs (circRNAs) are a class of covalently closed non-coding RNAs and are widely involved in various cancers including colorectal cancer (CRC). Circular RNA PVT1 (circPVT1) was reported in several malignancies but the role it plays in CRC remains unclear. In our current research, we focused on the expression and function of circPVT1) works in CRC. We found that circPVT1 was upregulated in CRC. Also, we illustrated that the upregulated circPVT1 was closely correlated with poor prognosis and bad clinicopathological features of patients with CRC. Through a loss of function experiment, we showed that a downregulation of circPVT1 suppressed CRC cells metastasis. Through online prediction, we found that circPVT1 had a microRNA response element (MRE) for miR-145. Additionally, we demonstrated that miR-145 was downregulated in CRC. Even further, we showed that miR-145 was involved in circPVT1 mediated facilitation of CRC metastasis. In a further mechanical study, we demonstrated that circPVT1 could target miR-145. Lastly, we revealed that the metastasis-promoting role of circPVT1 in CRC was partially achieved via miR-145 sponging. In brief, the findings of the present study illustrated that circPVT1, working as an oncogene, promotes metastasis via miR-145 sponging in CRC. CircPVT1/miR-145 axial might be a novel point in targeting treatment of CRC.

A novel long noncoding RNA, LINC00483 promotes proliferation and metastasis via modulating of FMNL2 in CRC.

Long non-coding RNAs (lncRNAs) are extensively involved in multiple malignancies including colorectal cancer (CRC). In the present study, we found a novel lncRNA, long intergenic non-protein coding RNA 483 (LINC00483), which was upregulated in CRC. We also illustrated that upregulated LINC00483 was correlated with poor clinicopathological features of patients with CRC. Functionally, we displayed that a knockdown of LINC00483 suppressed LOVO and HT29 cells proliferation and metastatic ability. We further illustrated that miR-204-3p was involved in LINC00483 induced proliferation and metastasis. An overexpression of miR-204-3p could attenuate the facilitative effect which LINC00483 presented. Through a luciferase assay, we showed the direct binding effect between LINC00483 and miR-204-3p. Even further, we revealed that LINC00483 and formin like 2 (FMNL2) shared a similar miR-204-3p response elements (MREs-204-3p). FMNL2 was a direct target of miR-204-3p. FMNL2 was a downstream gene of LINC00483 and participated in LINC00483 mediated proliferation and metastasis. Lastly, we proved that LINC00483 promoted proliferation and metastasis via modulating of FMNL2 in LOVO and HT29 cells. In summary, the outcomes of this study illustrated that LINC00483 promoted CRC cells proliferation and metastasis via modulating of FMNL2 by acting as a ceRNA of miR-204-3p. LINC00483/miR-204-3p/FMNL2 axial might be a novel target in molecular treatment of CRC.

Factors associated with smoking in Asian American adults: a systematic review.

This review systematically examined the factors associated with smoking in Asian American adults (aged > or =17 years). A total of 21 quantitative studies published in peer-reviewed journals from 1997 to 2006 were reviewed and abstracted using the matrix method. Statistically significant factors reported by the studies were summarized. Methodological quality of the studies also was assessed (maximum possible score = 10). Acculturation and education were the most frequently reported factors (n = 10, 47.6%). Acculturation was negatively associated with men's smoking but was positively associated with women's smoking. Education was uniformly found to be negatively related to smoking. Age was reported to have either a positive or a negative relationship with smoking (n = 9, 42.9%). Men were more likely to smoke than women (n = 7, 33.3%). The mean methodological score of the reviewed studies was 4.14 (on a scale of 1-10 points; SD = 1.62; range = 2-8). Health promotion professionals need to consider the summarized factors associated with Asian American adults' smoking behavior when planning smoking prevention programs and when recruiting participants for smoking cessation programs. When addressing acculturation, program planners should design different health education materials and use different strategies for men and women. To identify, understand, and incorporate essential factors into effective interventions, future studies should aim at higher methodological quality by using longitudinal design and increasing the use of theory, the test of data validity and reliability, and the report of effect sizes.