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The CRISPR/Cas systems in prokaryotes such as bacteria and archaea are the adaptive immune system to prevent infection from viruses, phages, or other foreign substances. When viruses or phages first invade the bacteria, Cas proteins recognize and cut the DNA from viruses or phages into short fragments that will be integrated into the CRISPR array. Once bacteria are invaded again, the modified CRISPR and Cas proteins react quickly to cut DNA at the specified target location, protecting the host. Due to its high efficiency, versatility, and simplicity, the CRISPR/Cas system has become one of the most popular gene editing technologies. In this review, we briefly introduce the CRISPR/Cas systems, focus on several delivery methods including physical delivery, viral vector delivery, and non-viral vector delivery, and the applications of disease therapy. Finally, some problems in CRISPR/Cas9 technology have been proposed, such as the off-target effects, the efficiency of DNA repair mechanisms, and delivery of CRISPR/Cas system safely and efficiently to the target location., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Huang, Zhou, Li, Lu and Liang.)

The carbon dioxide (CO 2 ) cycloaddition of epoxides to cyclic carbonates is of great industrial importance owing to the high economical values of its products. Single-atom catalysts (SACs) have great potential in CO 2 cycloaddition by virtue of their high atom utilization efficiency and desired activity, but they generally suffer from poor reaction stability and catalytic activity arising from the weak interaction between the active centers and the supports. In this work, Ir single atoms stably anchored on the WO 3 support (Ir 1 -WO 3 ) are developed with a strong electronic metal-support interaction (EMSI). Superior CO 2 cycloaddition is realized in the Ir 1 -WO 3 catalyst via the EMSI effect: 100% conversion efficiency for the CO 2 cycloaddition of styrene oxide to styrene carbonate after 15 h at 40 °C and excellent stability with no degradation even after ten reaction cycles for a total of more than 150 h. Density functional theory calculations reveal that the EMSI effect results in significant charge redistribution between the Ir single atoms and the WO 3 support, and consequently lowers the energy barrier associated with epoxide ring opening. This work furnishes new insights into the catalytic mechanism of CO 2 cycloaddition and would guide the design of stable SACs for efficient CO 2 cycloaddition reactions., (© 2022 Wiley-VCH GmbH.)

PhACs have attracted great attentions of researchers because of their potential ecological and healthy risks. However, their long-term pollution tendency study is very scarce. In this study, 32 target PhACs from surface water, wastewater treatment plants, fishponds and livestock farms were investigated in Wujin, a city located in the northeast of Tai Lake, using grab sampling. The occurrence, spatiotemporal distribution characteristics, potential sources, riverine flux and risk assessment were systematically analyzed. It was found that non-antibiotics were the mainly PhACs category in Wujin and CF, SMX were the predominant non-antibiotics and antibiotics, respectively. Besides, the average concentrations of total PhACs were 586.6 ng L -1 and 273.2 ng L -1 in 2018 and 2019, respectively. This improvement could be mainly attributed to the closure of fishponds and livestock farms. Moreover, CF/CBZ ratios which was considered as an indicator to trace untreated wastewater decrease significantly in 2019, and this was also a main reason for the improvement. Riverine flux could be calculated through arranging control sampling sites in the boundary and the net riverine inflow flux of PhACs in Wujin was 264.3 kg/a. Finally, CF, SMX, EM were evaluated as the high risk contaminants based on a comprehensive risk assessment method., (Copyright © 2021. Published by Elsevier B.V.)

The extensive application of plastic in human life brings about microplastic (MP) pollution in the environment. Identifying the potential sources of MPs is necessary to diminish its pollution. In this study, the occurrence, composition and distribution of MPs in the influents and effluents from 9 domestic wastewater treatment plants (WWTPs), 5 industrial WWTPs, wastewater of 10 industrial plants, 4 livestock farms and 4 fish ponds in China were investigated. Water samples were enzymatically treated followed by digestion with hydrogen peroxide and density separation. MPs were characterized using micro-Raman spectroscopy and were categorized by shape, size and color. Results showed that MP abundance in the influents and effluents of domestic WWTPs was 18-890 and 6-26 n·L -1 , respectively, with the removal efficiency ranging from 35 to 98%. The effluents of industrial WWTPs contained 6-12 n·L -1 and the levels of MPs in the wastewater of industrial plants, livestock farms and fish ponds were in the range of 8-23, 8-40 and 13-27 n·L -1 , respectively. No significant differences of MP abundance were demonstrated among effluents or wastewater of different sources, indicating they all constitute sources of MP pollution. Polyethylene (PE), polypropylene (PP) and polystyrene (PS) made up almost 83% of the total MPs. Fragment and film were the most abundant shapes and the majority of MPs were smaller than 500 μm. Polymer type and shape in different sources did not vary statistically, however, there were slight differences among different sources concerning size and color of MPs. This study could fill MP data gaps regarding different sources, guide future monitoring work and policy making., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Hepatocellular carcinoma (HCC) is known as a frequent type of primary cancer in the liver, and it is the third-most common cause of cancer-related death all over the world. However, the molecular mechanism in the progression of HCC is still unclear. The current study was designed to investigate the expression and function of microRNA-34a (miR-34a) in HCC. In HCC tissues and cells, the expression levels of miR-34a were analyzed by quantitative real-time polymerase chain reaction. The association between the level of miR-34a and hexokinase (HK)-1 was also investigated via luciferase reporter assay. Cell viability and proliferation were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and flow cytometry. To assess whether miR-34a can limit tumor growth in vivo, animal models and terminal deoxynucleotidyl transferase dUTP nick end labeling assay were used for examining the role of miR-34a on the development of HCC and cell apoptosis. The expression level of miR-34a was reduced in HCC samples and cells. The expression of miR-34a was associated with the viability and proliferation capacity of HCC cells, and miR-34a could inhibit HCC cells proliferation by inhibiting HK1. In the mouse model of HCC, volumes and weight of the tumors were significantly decreased by transfection with miR-34a mimic compared with the control group. Furthermore, miR-34a mimics could induce apoptosis in a greater proportion of cells compared with the control group. Taken together, the data may provide some novel insights into the molecular mechanism of miR-34a and HK1 in the progression of HCC. Thus, miR-34a/HK1 axis might be a novel promising therapeutic target for treating HCC., (© 2018 Wiley Periodicals, Inc.)

Mental health problems like anxiety, depression, and substance use problems commonly co-occur with cigarette smoking and are linked to poor cessation outcomes. Although millions of smokers seek online quitting assistance each year, few studies have examined links between website utilization and cessation outcomes among smokers with mental health problems. This study recruited 600 smokers with anxiety, depression, and alcohol use disorders (AUDs) who were new users of a publicly available Internet cessation treatment. Among participants with 3-month outcome data (n = 247, 42%), structural equation models (SEM) examined the association of symptoms of anxiety/depression (combined) and AUD diagnosis on website engagement and 3-month quit rates, controlling for covariates. The 3-month 30-day abstinence rate among those who completed follow-up was 28%, but only 14% among smokers with an AUD and 24.7% among smokers with symptoms of anxiety/depression. SEM results showed that treatment engagement significantly mediated the effect of mental health problems on 3-month abstinence: those with symptoms of anxiety/depression or an AUD had lower quit rates overall, however engagement with the website had a buffering effect on 3-month cessation outcomes. Engagement with an evidence-based Internet cessation program may be particularly useful for smokers with mental health comorbidities in increasing the chances of cessation. Future work should examine what level of treatment engagement meaningfully impacts behavior change for smokers with mental health problems who access Internet cessation programs., (Copyright © 2018. Published by Elsevier Inc.)

[This corrects the article DOI: 10.2196/mhealth.8123.]., (©Emily J Harvey, Leslie F Rubin, Sabrina L Smiley, Yitong Zhou, Hoda Elmasry, Jennifer L Pearson. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 19.03.2018.)

Background: Rather than providing participants with study-specific data collection devices, their personal mobile phones are increasingly being used as a means for collecting geolocation and ecological momentary assessment (EMA) data in public health research., Objective: The purpose of this study was to (1) describe the sociodemographic characteristics of respondents to an online survey screener assessing eligibility to participate in a mixed methods study collecting geolocation and EMA data via the participants' personal mobile phones, and (2) examine how eligibility criteria requiring mobile phone ownership and an unlimited text messaging plan affected participant inclusion., Methods: Adult (≥18 years) daily smokers were recruited via public advertisements, free weekly newspapers, printed flyers, and word of mouth. An online survey screener was used as the initial method of determining eligibility for study participation. The survey screened for twenty-eight inclusion criteria grouped into three categories, which included (1) cell phone use, (2) tobacco use, and (3) additional criteria., Results: A total of 1003 individuals completed the online screener. Respondents were predominantly African American (605/1003, 60.3%) (60.4%), male (514/1003, 51.3%), and had a median age of 35 years (IQR 26-50). Nearly 50% (496/1003, 49.5%) were unemployed. Most smoked menthol cigarettes (699/1003, 69.7%), and had a median smoking history of 11 years (IQR 5-21). The majority owned a mobile phone (739/1003, 73.7%), could install apps (86.8%), used their mobile phone daily (89.5%), and had an unlimited text messaging plan (871/1003, 86.8%). Of those who completed the online screener, 302 were eligible to participate in the study; 163 were eligible after rescreening, and 117 were enrolled in the study. Compared to employed individuals, a significantly greater proportion of those who were unemployed were ineligible for the study based on mobile phone inclusion criteria (P<.001); yet, 46.4% (333/717) of the individuals who were unemployed met all mobile phone inclusion criteria., Conclusions: Inclusion criteria requiring participants to use their personal mobile phones for data collection was not a major barrier to study participation for most respondents who completed the online screener, including those who were unemployed., Trial Registration: ClinicalTrials.gov NCT02261363; https://clinicaltrials.gov/ct2/show/NCT02261363 (Archived by WebCite at http://www.webcitation.org/6wOmDluSt)., (©Emily J Harvey, Leslie F Rubin, Sabrina L Smiley, Yitong Zhou, Hoda Elmasry, Jennifer L Pearson. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 19.02.2018.)