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A versatile terpene synthase (LcTPS2) producing unconventional macrocyclic terpenoids was characterized from Leucosceptrum canum. Engineered Escherichia coli and Nicotiana benthamiana expressing LcTPS2 produced six 18‐/14‐membered sesterterpenoids including five new ones and two 14‐membered diterpenoids. These products represent the first macrocyclic sesterterpenoids from plants and the largest sesterterpenoid ring system identified to date. Two variants F516A and F516G producing approximately 3.3‐ and 2.5‐fold, respectively, more sesterterpenoids than the wild‐type enzyme were engineered. Both 18‐ and 14‐membered ring sesterterpenoids displayed significant inhibitory activity on the IL‐2 and IFN‐γ production of T cells probably via inhibition of the MAPK pathway. The findings will contribute to the development of efficient biocatalysts to create bioactive macrocyclic sesterterpenoids, and also herald a new potential in the well‐trodden territory of plant terpenoid biosynthesis. [ABSTRACT FROM AUTHOR]

Summary: Eupatorium adenophorum is a malignant invasive plant possessing extraordinary defense potency, but its chemical weaponry and formation mechanism have not yet been extensively investigated.We identified six cadinene sesquiterpenes, including two volatiles (amorpha‐4,7(11)‐diene and (–)‐amorph‐4‐en‐7‐ol) and four nonvolatiles (9‐oxo‐10,11‐dehydroageraphorone, muurol‐4‐en‐3,8‐dione, 9‐oxo‐ageraphorone and 9β‐hydroxy‐ageraphorone), as the major constitutive and inducible chemicals of E. adenophorum. All cadinenes showed potent antifeedant activity against a generalist insect Spodoptera exigua, indicating that they have significant defensive roles.We cloned and functionally characterized a sesquiterpene synthase from E. adenophorum (EaTPS1), catalyzing the conversion of farnesyl diphosphate to amorpha‐4,7(11)‐diene and (–)‐amorph‐4‐en‐7‐ol, which were purified from engineered Escherichia coli and identified by extensive nuclear magnetic resonance (NMR) spectroscopy. EaTPS1 was highly expressed in the aboveground organs, which was congruent with the dominant distribution of cadinenes, suggesting that EaTPS1 is likely involved in cadinene biosynthesis. Mechanical wounding and methyl jasmonate negatively regulated EaTPS1 expression but caused the release of amorpha‐4,7(11)‐diene and (–)‐amorph‐4‐en‐7‐ol. Nicotiana benthamiana transiently expressing EaTPS1 also produced amorpha‐4,7(11)‐diene and (–)‐amorph‐4‐en‐7‐ol, and showed enhanced defense function.The findings presented here uncover the role and formation of the chemical defense mechanism of E. adenophorum – which probably contributes to the invasive success of this plant – and provide a tool for manipulating the biosynthesis of biologically active cadinene natural products. [ABSTRACT FROM AUTHOR]

The accurate identification of pests and their natural enemies is critically important in pest management. Without requiring specialized taxonomic expertise, molecular identification has been widely used in the recognition of pests and their natural enemies, as well as in the assessment of their trophic interactions. However, systematic comparative studies on the selection of molecular markers are often lacking. Trichogramma are the most widely used parasitoid wasps for controlling various lepidopteran pests in both agriculture and forests. The most commonly used molecular markers for Trichogramma are cytochrome oxidase subunit 1 (COI) and internal transcribed spacer 2 (ITS2). It is still controversial which marker is superior in Trichogramma molecular identification. We surveyed Trichogramma COI and ITS2 sequences available on NCBI and BOLD systems, performed PCR and Sanger sequencing for seven laboratory-reared Trichogramma species, and compared these two markers in several aspects. We found that ITS2 covers more species than COI in the public dataset, but its sequence misidentification rate is also higher than that of COI; ITS2 generally shows a faster substitution rate than COI, but COI sequences can be more divergent than ITS2 in some Trichogramma species; ITS2 has a higher copy number and PCR success rate than COI, but the proportion of double peaks in chromatograms of Sanger sequencing is also higher than that of COI. In summary, the molecular marks ITS2 and COI have different characteristics and can complement each other in the molecular identification of Trichogramma. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to investigate the potential factors associated with adherence to colonoscopy among participants who were preliminarily screened positive in a community‐based colorectal cancer screening program in China. Methods: This study analyzed data from 1219 out of 6971 community residents who were identified as positive cases by the well‐validated high‐risk factor questionnaire (HRFQ) or fecal immunochemical test (FIT) in the preliminary screening stage for colorectal neoplasms. Patients showing adherence to colonoscopy were defined as those who received positive results in a preliminary screening for colorectal neoplasms and later received a colonoscopy examination as required. The associations of social‐demographic factors, lifestyle behaviors, history of diabetes, body mass index (BMI), and risk factors in the HRFQ with adherence to colonoscopy were evaluated using logistic regression models. Results: Among 1219 participants who preliminarily screened positive, the top five risk factors reported by the participants were chronic constipation (25.9%), hematochezia (23.5%), family history of CRC in first‐degree relatives (22.1%), chronic diarrhea (21.8%), and history of polyps (16.6%). Around 14.2% of participants who preliminarily screened positive reported three or more risk factors, and the proportion was 26.2% among participants who were positive according to both HRFQ and FIT. Among all participants who were preliminarily screened positive, the multivariable results showed that those who were married (OR = 1.58, 95% CI: 1.12, 2.25, p = 0.01), had chronic diarrhea (OR = 1.34, 95% CI: 1.00, 1.78, p = 0.047), and had a positive FIT (OR = 1.60, 95% CI: 1.21, 2.10, p < 0.001 for patients who were negative according to HRFQ but positive according to FIT; OR = 2.12, 95% CI: 1.33, 2.78, p = 0.002 for patients who were positive for both HRFQ and FIT) were more likely to adhere to colonoscopy, while participants with a history of cancer (OR: 0.50, 95% CI: 0.31, 0.79, p = 0.003) were less likely to adhere to colonoscopy. The results among participants who were tested positive according to only HRFQ were similar to those among all participants who were tested positive according to HRFQ or FIT. However, among participants who were tested positive according to only FIT, we only found that those who were married (OR = 2.52, 95% CI: 1.08, 5.90, p = 0.033) had a higher odds of adhering to colonoscopy, while those with a history of diabetes (OR = 0.35, 95% CI: 0.13, 0.96, p = 0.042) were less likely to adhere to colonoscopy. Conclusion: Our findings provide evidence supporting the development of tailored interventional strategies that aim to improve adherence to colonoscopy for individuals with a high risk of colorectal neoplasms. Both barriers and facilitators associated with adherence to colonoscopy should be considered in supportive systems and health policies. However, further well‐designed prospective studies are warranted to confirm our findings. [ABSTRACT FROM AUTHOR]

C51H79O11Y, monoclinic, P21/c (no. 14), a = 8.8682(3) Å, b = 22.1328(8) Å, c = 27.9848(10) Å, β = 96.710(1)°, V = 5455.2(3) Å3, Z = 4, Rgt(F) = 0.0495, wRref(F2) = 0.1275, T = 296(2) K. [ABSTRACT FROM AUTHOR]

Objective: The objective of the study was to evaluate the usefulness of large-section cytokeratin 20 (CK20) staining technique in the detection of infiltration on the distal wall and mesangial metastasis in patients with middle and lower rectal cancer.Materials and Methods: A total of 62 patients with rectal cancer in the middle and lower segment were studied on large slices stained with CK20. Logistic regression was used to analyze the clinicopathologic factors related to distal low and middle rectal cancer metastasis to the mesorectum and rectal wall.Results: Two types of distal metastasis of the tumor were observed in the rectal wall in 18% (11/62) of the patients: submucosal invasion and muscularis propria invasion. The extent of distal metastasis to the rectal wall was around 0.5-1.0 cm. Four types of distal metastasis occurred in the mesorectum: lymph node invasion, blood and lymphatic vessel invasion, perineural invasion, and isolated neoplastic microfoci. Distal metastasis to the mesorectum was observed in 24% (15/62) of the patients. The extent of metastasis to the mesorectum was around 0.5-4.0 cm. Another three patients with microcapillary invasion in the distal mesorectum were observed by immunohistochemistry, as it was difficult to determine the spread by conventional hematoxylin and eosin staining.Conclusion: The large-section CK20 staining technique is useful for the detection of infiltration on the distal wall and mesangial metastasis in patients with middle and lower rectal cancer. [ABSTRACT FROM AUTHOR]