SnS2 quantum dots: facile synthesis, properties and applications in ultraviolet photodetector

Tin sulfide quantum dots (SnS2 QDs) are n-type wide band gap semiconductor. They exhibit a high optical absorption coefficient and strong photoconductive property in the ultraviolet and visible regions. Therefore, they have been found to have many potential applications, such as gas sensors, resistors, photodetectors, photocatalysts, and solar cells. However, the existing preparation methods for SnS2 QDs are complicated and require a high temperature and high pressure environment; hence they are unsuitable for large-scale industrial production. An effective method for the preparation of monodispersed SnS2 QDs at normal temperature and pressure will be discussed in this paper. The method is facile, green, and low-cost. In this work, the structure, morphology, optical, electrical, and photoelectric properties of SnS2 QDs are studied. The synthesized SnS2 QDs are homogeneous in size and exhibit good photoelectric performance. A photoelectric detector based on the SnS2 QDs is fabricated and its J-V and C-V characteristics are also studied. The detector responds under λ=365 nm light irradiation and reverse bias voltage. Its detectivity approximately stabilizes at 1011 Jones at room temperature. These results show the possible use of SnS2 QDs in photodetectors

Dietary fat intake and lung cancer risk: a pooled analysis

Purpose Dietary fat may play a role in lung carcinogenesis. Findings from epidemiologic studies, however, remain inconsistent. In this pooled analysis of 10 prospective cohort studies from the United States, Europe, and Asia, we evaluated the associations of total and specific types of dietary fat with lung cancer risk. Methods Cox regression was used to estimate hazard ratios (HRs) and 95% CIs in each cohort. Study-specific risk estimates were pooled by random- or fixed-effects meta-analysis. The first 2 years of follow-up were excluded to address potential influence of preclinical dietary changes. Results Among 1,445,850 participants, 18,822 incident cases were identified (mean follow-up, 9.4 years). High intakes of total and saturated fat were associated with an increased risk of lung cancer (for highest v lowest quintile: HR, 1.07 and 1.14, respectively; 95% CI, 1.00 to 1.15 and 1.07 to 1.22, respectively; P for trend for both < .001). The positive association of saturated fat was more evident among current smokers (HR, 1.23; 95% CI, 1.13 to 1.35; P for trend < .001) than former/never smokers (P for interaction = .004), and for squamous cell and small cell carcinoma (HR, 1.61 and 1.40, respectively; 95% CI, 1.38 to 1.88 and 1.17 to 1.67, respectively; P for trend for both < .001) than other histologic types (P for heterogeneity < .001). In contrast, a high intake of polyunsaturated fat was associated with a decreased risk of lung cancer (HR, 0.92; 95% CI, 0.87 to 0.98 for highest v lowest quintile; P for trend = .02). A 5% energy substitution of saturated fat with polyunsaturated fat was associated with a 16% to 17% lower risk of small cell and squamous cell carcinoma. No associations were found for monounsaturated fat. Conclusion Findings from this large, international cohort consortium suggest that modifying dietary fat intake (ie, replacing saturated fat with polyunsaturated fat) may reduce lung cancer risk, particularly among smokers and for squamous cell and small cell carcinoma

Longer telomere length in peripheral white blood cells is associated with risk of lung cancer and the rs2736100 (CLPTM1L-TERT) polymorphism in a prospective cohort study among women in China.

A recent genome-wide association study of lung cancer among never-smoking females in Asia demonstrated that the rs2736100 polymorphism in the TERT-CLPTM1L locus on chromosome 5p15.33 was strongly and significantly associated with risk of adenocarcinoma of the lung. The telomerase gene TERT is a reverse transcriptase that is critical for telomere replication and stabilization by controlling telomere length. We previously found that longer telomere length measured in peripheral white blood cell DNA was associated with increased risk of lung cancer in a prospective cohort study of smoking males in Finland. To follow up on this finding, we carried out a nested case-control study of 215 female lung cancer cases and 215 female controls, 94% of whom were never-smokers, in the prospective Shanghai Women's Health Study cohort. There was a dose-response relationship between tertiles of telomere length and risk of lung cancer (odds ratio (OR), 95% confidence interval [CI]: 1.0, 1.4 [0.8-2.5], and 2.2 [1.2-4.0], respectively; P trend = 0.003). Further, the association was unchanged by the length of time from blood collection to case diagnosis. In addition, the rs2736100 G allele, which we previously have shown to be associated with risk of lung cancer in this cohort, was significantly associated with longer telomere length in these same study subjects (P trend = 0.030). Our findings suggest that individuals with longer telomere length in peripheral white blood cells may have an increased risk of lung cancer, but require replication in additional prospective cohorts and populations

Association of untargeted urinary metabolomics and lung cancer risk among never-smoking women in China

Importance Chinese women have the highest rate of lung cancer among female never-smokers in the world, and the etiology is poorly understood. Objective To assess the association between metabolomics and lung cancer risk among never-smoking women. Design, Setting, and Participants This nested case-control study included 275 never-smoking female patients with lung cancer and 289 never-smoking cancer-free control participants from the prospective Shanghai Women’s Health Study recruited from December 28, 1996, to May 23, 2000. Validated food frequency questionnaires were used for the collection of dietary information. Metabolomic analysis was conducted from November 13, 2015, to January 6, 2016. Data analysis was conducted from January 6, 2016, to November 29, 2018. Exposures Untargeted ultra-high-performance liquid chromatography–tandem mass spectrometry and nuclear magnetic resonance metabolomic profiles were characterized using prediagnosis urine samples. A total of 39 416 metabolites were measured. Main Outcomes and Measures Incident lung cancer. Results Among the 564 women, those who developed lung cancer (275 participants; median [interquartile range] age, 61.0 [52-65] years) and those who did not develop lung cancer (289 participants; median [interquartile range] age, 62.0 [53-66] years) at follow-up (median [interquartile range] follow-up, 10.9 [9.0-11.7] years) were similar in terms of their secondhand smoke exposure, history of respiratory diseases, and body mass index. A peak metabolite, identified as 5-methyl-2-furoic acid, was significantly associated with lower lung cancer risk (odds ratio, 0.57 [95% CI, 0.46-0.72]; P < .001; false discovery rate = 0.039). Furthermore, this peak was weakly correlated with self-reported dietary soy intake (ρ = 0.21; P < .001). Increasing tertiles of this metabolite were associated with lower lung cancer risk (in comparison with first tertile, odds ratio for second tertile, 0.52 [95% CI, 0.34-0.80]; and odds ratio for third tertile, 0.46 [95% CI, 0.30-0.70]), and the association was consistent across different histological subtypes and follow-up times. Additionally, metabolic pathway analysis found several systemic biological alterations that were associated with lung cancer risk, including 1-carbon metabolism, nucleotide metabolism, oxidative stress, and inflammation. Conclusions and Relevance This prospective study of the untargeted urinary metabolome and lung cancer among never-smoking women in China provides support for the hypothesis that soy-based metabolites are associated with lower lung cancer risk in never-smoking women and suggests that biological processes linked to air pollution may be associated with higher lung cancer risk in this population

Prediction of breast cancer risk based on common genetic variants in women of East Asian ancestry

$\textbf{BACKGROUND}$: Approximately 100 common breast cancer susceptibility alleles have been identified in genome-wide association studies (GWAS). The utility of these variants in breast cancer risk prediction models has not been evaluated adequately in women of Asian ancestry. $\textbf{METHODS}$: We evaluated 88 breast cancer risk variants that were identified previously by GWAS in 11,760 cases and 11,612 controls of Asian ancestry. SNPs confirmed to be associated with breast cancer risk in Asian women were used to construct a polygenic risk score (PRS). The relative and absolute risks of breast cancer by the PRS percentiles were estimated based on the PRS distribution, and were used to stratify women into different levels of breast cancer risk. $\textbf{RESULTS}$: We confirmed significant associations with breast cancer risk for SNPs in 44 of the 78 previously reported loci at $\textit{P}$ < 0.05. Compared with women in the middle quintile of the PRS, women in the top 1% group had a 2.70-fold elevated risk of breast cancer (95% CI: 2.15-3.40). The risk prediction model with the PRS had an area under the receiver operating characteristic curve of 0.606. The lifetime risk of breast cancer for Shanghai Chinese women in the lowest and highest 1% of the PRS was 1.35% and 10.06%, respectively. $\textbf{CONCLUSION}$: Approximately one-half of GWAS-identified breast cancer risk variants can be directly replicated in East Asian women. Collectively, common genetic variants are important predictors for breast cancer risk. Using common genetic variants for breast cancer could help identify women at high risk of breast cancer.The work conducted for this project at Vanderbilt University (SBCGS, SGWAS, SGWAS_stage2) was supported in part by US National Institutes of Health grants (R01CA124558, R01CA148667, R37CA070867, R01CA118229, R01CA092585, R01CA064277, R01CA122756, R01CA137013), US Department of Defense Idea Awards (BC011118, BC050791), and Ingram Professorship and Research Reward funds. The BCAC was funded by Cancer Research UK (C1287/A10118, C1287/A12014) and by the European Community’s Seventh Framework Programme under grant agreement number 223175 (grant number HEALTH-F2-2009-223175) (COGS). For further information regarding funding, please visit the publisher's website