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An enantioselective nickel-catalyzed intramolecular reductive cross-coupling of C(sp

Background The aim of this study was to compare epidermal growth factor receptor (EGFR) mutations between primary tumors and corresponding bone metastases (BMs) in lung adenocarcinoma. Materials and methods In total, 115 paired primary lung adenocarcinoma and corresponding BM tumors were analyzed for EGFR mutations by Amplification Refractory Mutation System. Results EGFR mutations were detected in 61 primary lung adenocarcinomas (53.04%) and in 67 corresponding metastases (58.26%), respectively. The EGFR mutation rate was significantly higher in female and in never-smoker patients. The consistency of EGFR mutations between the 115 matched BMs and primary tumor tissue samples reached to 80.87%, and the disparity was 19.13%. Mutations in exons 19 (19-del) and 21 (point mutation L858R) were the predominant mutation type. Conclusions The concordance rate demonstrated the feasibility of EGFR mutations in corresponding metastases using Amplification Refractory Mutation System when the primary tumor tissue is unavailable in the lung adenocarcinoma patients, and the inconsistency indicates that corresponding metastasis being screened simultaneously with the primary tumor samples may present some supplementary information for the patients.

An enantioselective Pd(II)-catalyzed amino-cyclization and desymmetrizing nitrile addition cascade reaction of alkyne-tethered malononitriles is reported. This reaction forms two rings and one quaternary carbon center in a single step and serves as an efficient strategy for the construction of α-quaternary carbazolones with high enantioselectivities (up to 98:2 er). The utility of this method is demonstrated by product derivatization into a diverse array of heterocycles and a nitrile-containing leucomidine A analog.

Purpose Approximately 10% of gastrointestinal stromal tumors (GISTs) are devoid of KIT, PDGFRA (platelet-derived growth factor-alpha), BRAF, and SDH alterations. The aim of this study was to characterize molecular drivers in Chinese patients with quadruple-negative GISTs. Patients and methods In 1022 Chinese patients with GIST, mutations of KIT and PDGFRA were analyzed by direct sequencing. Of these mutations, 142 KIT/PDGFRA wild-type (WT) GISTs were detected, and succinate dehydrogenase (SDH) deficiency was determined using immunohistochemistry analysis of succinate dehydrogenase B. In 78 KIT/PDGFRA/SDH cases, we performed targeted 425 cancer-related gene analysis using next-generation sequencing. The correlation between molecular findings and clinicopathologic features was also analyzed. Results We defined 72 quadruple-negative GISTs from enrollments. They featured nongastric localization with histologic characteristics of spindle cells and male predilection. An overall 27.78% (20/72) of quadruple-negative tumors carried TP53, and 25.00% (18/72) carried RB1 mutations, which were frequently associated with high mitotic index and large size. TP53 analyses demonstrated coexistence with mutational activation of other oncogenes in 12 of 20 cases. A total of 18 RB1-mutated cases were independent of TP53. Further, no tumors carried NF1 and BRAF mutations. Conclusions We report the genomic analysis of Chinese quadruple-negative patients. These databases may help advance our understanding of quadruple-negative GISTs' progression. Next-generation sequencing from GISTs is feasible to provide relevant data for guiding individualized therapy.

Background: The diffuse sclerosing variant of papillary thyroid carcinoma (DSVPC) is a rare variant of papillary thyroid carcinoma with features of strong ability of invasion, metastasis, relapse, and mortality. Its diagnosis is difficult to obtain because of the special differentiation state of the cancer cells. Case Presentation: A 21-year-old woman arrived at the First Affiliated Hospital of China Medical University in October 2019 because of a peach-pit-sized mass that she had noticed 1 month before. Color duplex ultrasonography findings suggested a thyroid nodule. Conclusions: Based on findings of the specialist examination, physical examination, and thyroid ultrasonography, the patient was initially diagnosed with thyroid neoplasm. Under general anesthesia, thyroidectomy was performed, removing the right lobe and isthmus, and biopsy specimens were obtained from lymph node groups III, IV, and VI on the right side. The final histological diagnosis was DSVPC.

Although the use of pleural effusion samples for epidermal growth factor receptor (EGFR) testing in lung cancer is increasing, the accuracy rate and effectiveness of identifying EGFR mutations using these samples, rather than primary tumor tissue samples, is not established.One hundred ninety-two advanced, non-small cell lung cancer patients were enrolled into this study. All patients had primary tumor tissue and corresponding pleural effusion samples, and we employed the Amplification Refractory Mutation System to detect EGFR gene mutations in these samples.The number of EGFR mutations detected in primary tumor tissue and pleural effusion samples was 119 (61.98%) and 113 (58.85%), respectively. The EGFR-mutation rate was significantly higher in female than in male patients, and in adenocarcinoma than in nonadenocarcinoma patients (P=0.000). Single mutations in exons 19 and 21 were the predominant observed mutation type, and the overall concordance rate of EGFR-mutation status between the 192 matched pleural effusion and primary tumor tissue samples was 86.98%.We observed a high concordance rate between EGFR mutations identified using primary tumor tissue and corresponding pleural effusion samples by Amplification Refractory Mutation System. Thus, it is likely that pleural effusion sampling from advanced non-small cell lung cancer patients, especially those with adenocarcinoma, may be effective in EGFR-mutation screening.

To explore the influence of the interface charges on the threshold voltage of pMOSFET, we present a novel device model in this paper. By dividing the gate oxide layer into several regions, and setting different interface charges in different regions, the relationship between the interface charges' length and the threshold voltage is well simulated by using 2D numerical simulation, in which the conditions of drain biasing and interface charges' concentration are considered. At the same time, the mechanism of threshold voltage variation is also investigated by comparing the surface potentials of various models. The proposed work can promote the research on Drain Bias-Negative Bias Temperature Instability (DB-NBTI) effect.

By using the MOS energy band diagram and Negative Bias Temperature Instability (NBTI) degradation model, an equation of NBTI degradation with channel doping concentration has been derived. Meanwhile, a new NBTI inhibition method by using different doping concentration has been proposed. The quantitatively calculation and simulation results show that, with the proposed method, the NBTI inhibition rate can reach 25.6%. The fruit in this research can be used to design integrated circuits and devices with high reliability.

An analysis model of the dV/dt capability for a metal—oxide—semiconductor (MOS) controlled thyristor (MCT) is developed. It is shown that, in addition to the P-well resistance reported previously, the existence of the OFF-FET channel resistance in the MCT may degrade the dV/dt capability. Lower P-well and N-well dosages in the MCT are useful in getting a lower threshold voltage of OFF-FET and then a higher dV/dt immunity. However, both dosages are restricted by the requirements for the blocking property and the forward conduction capability. Thus, a double variable lateral doping (DVLD) technique is proposed to realize a high dV/dt immunity without any sacrifice in other properties. The accuracy of the developed model is verified by comparing the obtained results with those from simulations. In addition, this DVLD MCT features mask-saving compared with the conventional MCT fabrication process. The excellent device performance, coupled with the simple fabrication, makes the proposed DVLP MCT a promising candidate for capacitor discharge applications.