A generic strategy based on gas phase decomposition of protonated and ammoninted precursors producing predictable MRM-MS ion pairs and collision energies for direct analysis of plant triterpene glycosides.

Optimization of multiple reaction monitoring mass spectrometry (MRM-MS) parameters of triterpene glycosides (TGs) using traditional infusion methods remains to be labor-intensive. However, it was found that mild gas phase decompositions of protonated and ammoninted precursors (DPAP) of TGs could produce a series of abundant dehydrated product ions of aglycones ([A+H-nH2O]+ (n = 0, 1, 2, 3…)) with high efficiency and stability. Based on these considerations and findings, an innovative ESI+-MRM-DPAP-MS strategy was devised on a QTRAP 4000 instrument allowing for rapid the qualitative and quantitative analysis of plant TGs. A detailed study of 85 model compounds from 20 herbal medicines was implemented for validation and evaluation of the ESI+-MRM-DPAP-MS strategy proposed. The central composition design confirmed that collision energy (CE) played more significant roles than declustering potentials (DP) for the formation of these Q1/Q3 ion pairs based on MRM-DPAP-MS. It is also noted that Q1 and Mw were the most important factors for the prediction of CE values by a partial least square regression model. Here, we demonstrated this generic workflow and its merits in: (1) early prediction and selection of MRM ion pairs, no matter which type of TGs, employing a new-found Q1/Q3 calculation formula (Q1=[M+H/NH4]+ and Q3= [A+H-nH2O]+ (n = 0, 1, 2, 3…)); (2) direct determination of practicable CE values using TGs-specific CE-estimating linear equations; (3) appearances of excellent sensitivity, stability and repeatability through real application in Aralia elata, Panax notoginseng and Caulophyllum robustum; (4) seamless application of optimal CE parameters in other triple quadrupole MS instruments such as Thermo TSQ Quantum Ultra. The ESI+-MRM- DPAP-MS may service as an effective and feasible approach for analytical characterization of biological TGs from herbal medicines.

Early pregnancy following multidrug regimen chemotherapy in a gestational trophoblastic neoplasia patient: A case report.

RATIONALE: Gestational trophoblastic neoplasia is a group of rare tumors that can be cured using chemotherapy. The use of artificial contraception for at least 1 year is recommended not only due to the high recurrence rate in the first year after treatment, but also because of the unclear genetic toxic effects of multidrug regimen chemotherapy on reproductive cells. There is no consensus about the contraception duration, but most patients want to have children. PATIENT CONCERNS: This case involved a 33-year-old female suffering from gestational trophoblastic neoplasia and 5-fluorouracil + actinomycin-D chemotherapy. She became pregnant 1 month after finishing the chemotherapy. DIAGNOSIS: Gestational trophoblastic neoplasia. INTERVENTIONS: No treatment during pregnancy. OUTCOMES: The patient had a full-term normal delivery, and the baby showed normal development and growth after a follow-up of 48 months. LESSONS: Pregnancy soon after chemotherapy can be viable with rigorous prenatal care.