Refractive uses of layered and two-dimensional materials for integrated photonics

The scientific community has witnessed tremendous expansion of research on layered (i.e. two-dimensional, 2D) materials, with increasing recent focus on applications to photonics. Layered materials are particularly exciting for manipulating light in the confined geometry of photonic integrated circuits, where key material properties include strong and controllable light-matter interaction, and limited optical loss. Layered materials feature tunable optical properties, phases that are promising for electro-optics, and a panoply of polymorphs that suggest a rich design space for highly-nonperturbative photonic integrated devices based on phase-change functionality. All of these features are manifest in materials with band gap above the photonics-relevant near-infrared (NIR) spectral band ($\sim$ 0.5 - 1 eV), meaning that they can be harnessed in refractive (i.e. non-absorptive) applications.Comment: review paper. ACS Photonics (2020

Methyl jasmonate-induced accumulation of metabolites and transcriptional responses involved in triterpene biosynthesis in Siraitia grosvenorii fruit at different growing stages

The cucurbitane-type triterpenoid glycosides, mogrosides, are the main active components of Siraitia grosvenorii fruit. Squalene and cucurbitadienol are among the intermediates of the biosynthetic pathway for the formation of cucurbitane-type triterpenoid backbones of mogrosides. It is recognized that the exogenous application of methyl jasmonate (MeJA) increases the accumulation of secondary metabolites in various plant species. Here, the effect of MeJA (50, 200, and 500 μM) on the accumulation of squalene and cucurbitadienol in the fruits of S. grosvenorii at 10, 20, and 30 days after flowering (DAF) was tested for the first time. Since mogroside II E is the main cucurbitane-type triterpenoid present at this time, its concentration was also determined. The results show that MeJA can indeed promote squalene and cucurbitadienol accumulation, the application of 500 μM MeJA at 30 DAF being optimal. The concentration of squalene and cucurbitadienol increased up to 0.43 and 4.71 μg/g dry weight (DW), respectively, both of which were 1.2-fold greater than that of the control. The content of mogroside II E increased by 15% over the untreated group. We subsequently analyzed the expression of key genes involved in the mogroside biosynthetic pathway, including the 3-hydroxy-3-methylglutaryl-coenzyme A reductase gene (SgHMGR), squalene synthetase gene (SgSQS), cucurbitadienol synthase gene (SgCS), and cytochrome P450 (SgCYP450) with quantitative real-time PCR. The results showed that transcriptional levels of these genes were upregulated following the treatment described above. Additionally, their responses in the presence of MeJA was related to the concentration and timing of MeJA treatment

Methyl jasmonate-induced accumulation of metabolites and transcriptional responses involved in triterpene biosynthesis in Siraitia grosvenorii fruit at different growing stages

The cucurbitane-type triterpenoid glycosides, mogrosides, are the main active components of Siraitia grosvenorii fruit. Squalene and cucurbitadienol are among the intermediates of the biosynthetic pathway for the formation of cucurbitane-type triterpenoid backbones of mogrosides. It is recognized that the exogenous application of methyl jasmonate (MeJA) increases the accumulation of secondary metabolites in various plant species. Here, the effect of MeJA (50, 200, and 500 μM) on the accumulation of squalene and cucurbitadienol in the fruits of S. grosvenorii at 10, 20, and 30 days after flowering (DAF) was tested for the first time. Since mogroside II E is the main cucurbitane-type triterpenoid present at this time, its concentration was also determined. The results show that MeJA can indeed promote squalene and cucurbitadienol accumulation, the application of 500 μM MeJA at 30 DAF being optimal. The concentration of squalene and cucurbitadienol increased up to 0.43 and 4.71 μg/g dry weight (DW), respectively, both of which were 1.2-fold greater than that of the control. The content of mogroside II E increased by 15% over the untreated group. We subsequently analyzed the expression of key genes involved in the mogroside biosynthetic pathway, including the 3-hydroxy-3-methylglutaryl-coenzyme A reductase gene (SgHMGR), squalene synthetase gene (SgSQS), cucurbitadienol synthase gene (SgCS), and cytochrome P450 (SgCYP450) with quantitative real-time PCR. The results showed that transcriptional levels of these genes were upregulated following the treatment described above. Additionally, their responses in the presence of MeJA was related to the concentration and timing of MeJA treatment

Effectiveness of artificial intelligence-assisted ultrasound for breast cancer screening in Chinese women

Background and purpose: Artificial intelligence (AI) technology is increasingly being used in the medical field. This study aimed to assess the effectiveness of artificial intelligence ultrasound system for identifying breast lesions in Chinese women and its role in breast cancer early detection. Methods: A prospective study was conducted on healthy women aged 35-74 years who came to Fudan University Shanghai Cancer Center from August 2020 to December 2020 for breast ultrasonography. All the women were examined by AI-assisted ultrasound first, and then by conventional ultrasonography. We compared the differences between AI-assisted ultrasound and conventional ultrasonography in identifying breast lesions in Chinese women. One year later, we looked up the hospital medical history and Shanghai Cancer Registration Management System for the final diagnosis of breast cancer. Results: A total of 360 women were included in the study and received breast examinations using both AI-assisted ultrasound and conventional ultrasound. A total of 2 504 breast lesions were detected, of which, 2 217 were detected by AI-assisted ultrasound, with a lesion recognition rate of 88.5%. Conventional ultrasound identified 1 090 lesions, with a lesion recognition rate of 43.5%. Using conventional ultrasound as the standard, the sensitivity and specificity of AI-assisted ultrasound for Breast Imaging Reporting and Data System (BI-RADS) level 4 and above lesions were 93.3% (95% CI: 80.7-98.3) and 100.0% (95% CI: 99.5-100.0), respectively. During one-year follow-up, 10 patients were diagnosed with breast cancer, and 8 of whom were identified by both AI-assisted ultrasound and conventional B ultrasound. The sensitivity of AI-assisted ultrasound and conventional ultrasound for breast cancer was 80.0% (95% CI: 44.2-96.4), and the specificity was 88.6% (95% CI: 84.6-91.6). Conclusion: AI-assisted ultrasound has good identification ability for breast lesions in Chinese women. The recognition ability for high-risk breast lesions (BI-RADS 4A and above) and early breast cancer is equivalent to that of conventional ultrasound, which is suitable for breast cancer screening in large-scale community of women with general risk

Survival and cause-of-death analysis of 55 thousand thyroid cancer cases in China from a large single institution hospital-based cancer registry database

Background and purpose: Thyroid cancer is the most common malignant endocrine tumor, particularly prevalent among the Asian population. The overall survival for thyroid cancer patients is relatively high, but there are significant survival differences among patients. Based on long-term hospital-based cancer registry database, this study analyzed the 10-year observed overall survival (OS) rate of thyroid cancer cases and the distribution of causes of death, providing real-world evidences to further survival management of thyroid cancer in China. Methods: A total of 55343 thyroid cancer patients who underwent treatment at Fudan University Shanghai Cancer center from 2005 to 2021 were included in this study. Clinical information and the follow-up endpoint data were collected through medical records review, telephone visits and death registry data linkage. The last follow-up date was October 31, 2024. Kaplan-Meier method was applied in evaluating the OS rate, and survival data were described by different subgroups as age group, gender, treatment period, tumor staging and pathological characteristics. The standardized mortality ratio (SMR) and absolute excess risk (AER) were calculated using general Shanghai population as the reference, and the mortality risk was described by gender, age at diagnosis and histological subtype. Results: With a median follow-up time of 63.01 months, the overall 1-, 3-, 5- and 10-year OS rates of thyroid cancer patients were 99.67% (95% CI: 99.62%-99.72%), 99.11% (95% CI: 99.03%-99.19%), 98.48% (95% CI: 98.36%-98.60%) and 95.81% (95% CI: 95.50%-96.11%), respectively. The 10-year OS rates of stage Ⅰ, Ⅱ, Ⅲ and Ⅳ were 97.99% (95% CI: 97.70%-98.28%), 89.80% (95% CI: 87.24%-92.37%), 77.84% (95% CI: 70.76%-84.92%) and 62.95% (95% CI: 55.37%-70.54%), respectively. The differences in OS among patients with different age, gender and histological classification were significant. 1256 (2.27%) deaths occurred, of which 18.63%, 50.88% and 7.32% were attributable to thyroid cancer, other cancers and cardiovascular disease (CVD), respectively. Compared with the general population, patients with different subtypes of thyroid cancer had higher all-cause mortality rates, progressively increasing with papillary, follicular, medullary and anaplastic thyroid carcinoma/poorly differentiated carcinoma. Compared with general population, the death risk was 2.24 times higher in papillary thyroid cancer patients (95% CI: 2.06-2.44), 9.94 times higher in follicular thyroid cancer patients (95% CI: 6.79-14.09), 12.16 times higher in medullary thyroid cancer patients (95% CI: 8.05-17.69), and the highest risk was observed in patients with anaplastic thyroid carcinoma/poorly differentiated carcinoma [SMR=79.67 (95% CI: 58.38-106.31), AER=766.01/1 000 person-years]. Conclusion: The 10-year long survival data and cause of death for thyroid cancer patients with different histological types were reported in China based on a large single institution hospital-based cancer registry database. Staging and histological characteristics were the most important factors directly affected the survival. Early diagnosis and individualized treatment are crucial for improving prognosis

An efficient approach to finding Siraitia grosvenorii triterpene biosynthetic genes by RNA-seq and digital gene expression analysis

<p>Abstract</p> <p>Background</p> <p><it>Siraitia grosvenorii </it>(Luohanguo) is an herbaceous perennial plant native to southern China and most prevalent in Guilin city. Its fruit contains a sweet, fleshy, edible pulp that is widely used in traditional Chinese medicine. The major bioactive constituents in the fruit extract are the cucurbitane-type triterpene saponins known as mogrosides. Among them, mogroside V is nearly 300 times sweeter than sucrose. However, little is known about mogrosides biosynthesis in <it>S. grosvenorii</it>, especially the late steps of the pathway.</p> <p>Results</p> <p>In this study, a cDNA library generated from of equal amount of RNA taken from <it>S. grosvenorii </it>fruit at 50 days after flowering (DAF) and 70 DAF were sequenced using Illumina/Solexa platform. More than 48,755,516 high-quality reads from a cDNA library were generated that was assembled into 43,891 unigenes. De novo assembly and gap-filling generated 43,891 unigenes with an average sequence length of 668 base pairs. A total of 26,308 (59.9%) unique sequences were annotated and 11,476 of the unique sequences were assigned to specific metabolic pathways by the Kyoto Encyclopedia of Genes and Genomes. cDNA sequences for all of the known enzymes involved in mogrosides backbone synthesis were identified from our library. Additionally, a total of eighty-five cytochrome P450 (CYP450) and ninety UDP-glucosyltransferase (UDPG) unigenes were identified, some of which appear to encode enzymes responsible for the conversion of the mogroside backbone into the various mogrosides. Digital gene expression profile (DGE) analysis using Solexa sequencing was performed on three important stages of fruit development, and based on their expression pattern, seven <it>CYP450</it>s and five <it>UDPG</it>s were selected as the candidates most likely to be involved in mogrosides biosynthesis.</p> <p>Conclusion</p> <p>A combination of RNA-seq and DGE analysis based on the next generation sequencing technology was shown to be a powerful method for identifying candidate genes encoding enzymes responsible for the biosynthesis of novel secondary metabolites in a non-model plant. Seven <it>CYP450</it>s and five <it>UDPG</it>s were selected as potential candidates involved in mogrosides biosynthesis. The transcriptome data from this study provides an important resource for understanding the formation of major bioactive constituents in the fruit extract from <it>S. grosvenorii</it>.</p