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1.
J Cell Physiol ; 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32026471

RESUMO

The expression pattern and role of circular RNAs (circRNAs) in the pathogenesis of gastric cancer (GC) and their underlying mechanisms remain unresolved. In this study, we identified differentially expressed circRNAs by a circRNA microarray and verified the results by quantitative reverse transcription-polymerase chain reaction using 117 clinical samples. Cell Counting Kit-8, wound healing, Transwell, and tumorsphere formation assays were conducted to assess the effects of circ-CEP85L on cell proliferation and invasion in vitro. Mouse intraperitoneal injection models were used to assess the functions of circ-CEP85L in vivo. Luciferase reporter assays, fluorescence in situ hybridization, and rescue experiments were performed to elucidate the underlying mechanism of circ-CEP85L. We found that circ-CEP85L, which has not been studied in GC, was significantly downregulated in GC tissues and that decreased circ-CEP85L expression correlated significantly with a worse prognosis. The knockdown of circ-CEP85L promoted the proliferation and invasion of GC cells, which was reversed by overexpression of circ-CEP85L. Furthermore, inhibition of circ-CEP85L promoted tumor growth in vivo. Mechanistically, circ-CEP85L was confirmed to be a direct target of miR-942-5p. In addition, rescue experiments indicated that circ-CEP85L is able to inhibit the proliferation and invasion of GC cells by sponging miR-942-5p. Finally, western blot assays verified that the downregulation of miR-942-5p efficiently reversed the inhibition of NFKBIA induced by circ-CEP85L overexpression. Therefore, we conclude that circ-CEP85L promotes NFKBIA expression by acting as a sponge of miR-942-5p; thus, inhibiting GC proliferation and invasion. circ-CEP85L is a potential target in the treatment of GC.

2.
Eur J Surg Oncol ; 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-32044202

RESUMO

BACKGROUND: and purpose: For gastric cancer patients with peritoneal metastasis (GCPM), there is no universally accepted prognostic staging system. This study aimed to validate the predictive ability of the 15th peritoneal metastasis staging system (P1abc) of the Japanese Classification of Gastric Carcinoma (JCGC). METHODS: The data of 309 GCPM patients from July 2007 to July 2017 were retrospectively analyzed. This study compared the prognosis prediction performances of P1abc, the previous JCGC PM staging (P123) and Gilly staging systems. RESULTS: The survival curve revealed a significant difference in overall survival (OS) predicted by P1abc, P123 and Gilly staging (all P < 0.05), and the survival of the two adjacent substages were well distinguished by P1abc but not by P123 and Gilly staging. Both P123 and Gilly staging were substituted with P1abc staging in a 2-step multivariate analysis. The results showed that P1abc staging was superior to both P123 and Gilly staging in its discriminatory ability (C-index), predictive accuracy (AIC) and predictive homogeneity (likelihood ratio chi-square). A stratified analysis by different therapies indicated that for the P1a and P1b patients, OS following palliative resection combined with palliative chemotherapy (PRCPC) was better than that after palliative resection (PR) or palliative chemotherapy (PC) alone (P < 0.05). For the P1c patients, OS after receiving PC was significantly superior to that after receiving PRCPC or PR (P = 0.021). CONCLUSION: P1abc staging is superior to P123 and Gilly staging in predicting the survival of GCPM patients. Surgeons can provide these patients with appropriate treatment options according to the corresponding substages within P1abc.

4.
Radiology ; : 200343, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32049601

RESUMO

Some patients with positive chest CT findings may present with negative results of real time reverse-transcription-polymerase chain- reaction (RT-PCR) for 2019 novel coronavirus (2019-nCoV). In this report, we present chest CT findings from five patients with 2019-nCoV infection who had initial negative RT-PCR results. All five patients had typical imaging findings, including ground-glass opacity (GGO) (5 patients) and/or mixed GGO and mixed consolidation (2 patients). After isolation for presumed 2019-nCoV pneumonia, all patients were eventually confirmed with 2019-nCoV infection by repeated swab tests. A combination of repeated swab tests and CT scanning may be helpful when for individuals with high clinical suspicion of nCoV infection but negative RT-PCR screening.

5.
Nat Commun ; 11(1): 842, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32051404

RESUMO

Developing high-efficient afterglow from metal-free organic molecules remains a formidable challenge due to the intrinsically spin-forbidden phosphorescence emission nature of organic afterglow, and only a few examples exhibit afterglow efficiency over 10%. Here, we demonstrate that the organic afterglow can be enhanced dramatically by thermally activated processes to release the excitons on the stabilized triplet state (T1*) to the lowest triplet state (T1) and to the singlet excited state (S1) for spin-allowed emission. Designed in a twisted donor-acceptor architecture with small singlet-triplet splitting energy and shallow exciton trapping depth, the thermally activated organic afterglow shows an efficiency up to 45%. This afterglow is an extraordinary tri-mode emission at room temperature from the radiative decays of S1, T1, and T1*. With the highest afterglow efficiency reported so far, the tri-mode afterglow represents an important concept advance in designing high-efficient organic afterglow materials through facilitating thermally activated release of stabilized triplet excitons.

6.
J Gastrointest Surg ; 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32016671

RESUMO

BACKGROUND: Whether the change of the pre- and postoperative systemic inflammatory response (SIR) levels will affect the prognosis of gastric cancer (GC) is unclear. We aimed to investigate the dynamic changes in the pre- and postoperative SIR and their prognostic value for GC. METHODS: The clinicopathological data from 2257 patients who underwent radical gastrectomy between January 2009 and December 2014 at Fujian Medical University Union Hospital (FMUUH) were analyzed. Perioperative SIR changes were reported as changes in the lymphocyte-monocyte ratio (LMR), neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII). RESULTS: The SIR levels showed different trends from postoperative months 1 to 12. Multivariate analysis showed that preoperative (pre)-LMR was an independent predictor for the prognosis (P = 0.024). The postoperative 12-month (post-12-month) LMR predicted the 5-year overall survival (OS) rate with the highest accuracy (areas under the curve [AUC] 0.717). Patients were divided into four groups according to the optimal cutoff of the preoperative and post-12-month LMR: high pre-LMR to high postoperative (post)-LMR group, high pre-LMR to low post-LMR group, low pre-LMR to high post-LMR group, and low pre-LMR to low post-LMR group. The survival analysis showed 5-year OS rate was significantly higher in patients with high post-12-month LMR than in patients with low post-12-month LMR, regardless of pre-LMR levels (81.6% vs. 44.2%, P < 0.001). The prognostic accuracy was significantly improved by incorporating the post-12-month LMR in the tumor-node-metastasis (TNM) staging system (P = 0.003). CONCLUSIONS: The remeasurement of LMR at post-12-month is helpful in predicting the long-term survival of GC.

7.
Phys Chem Chem Phys ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32002525

RESUMO

Heteroatom incorporation is highly effective in tuning the molecular structures and optoelectronic properties of conjugated organic molecules. Here, we performed systematic theoretical studies on heteroatom-bridged heterofluorenes (BXFs) constructed by double heteroatom bridges of biphenyl to reveal the effects of heavily incorporated heteroatoms on molecular architecture and π-conjugation for different optoelectronic properties. Nine novel BXFs in three series were investigated and all of them exhibit promising potential optoelectronic properties owing to their highly fused molecular structure with heavy π-conjugation, although the introduction of different types and numbers of heteroatoms will lead to varied properties. Moreover, spiropolymers of BSiF and BGeF polymerized at the bridging position were also designed for the first time and found to have attractive optoelectronic properties of poly(BXF)s inherited from their monomers, demonstrating further the effectiveness of the bis-heteroatom introduction strategy in the construction of high-performance optoelectronic polymers. This heteroatom introduction strategy in constructing highly rigid π-conjugated materials could be applicable to other systems, representing a new concept advance to design novel conjugated small molecules and polymers for high-performance optoelectronic applications.

8.
Acta Biomater ; 104: 210-220, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31927113

RESUMO

Multi-modality imaging agents are desirable for tumor diagnosis because they can provide more alternative and reliable information for accurate detection and therapy of diseases than single imaging technique. However, most reported conventional imaging agents have not been found to successfully overcome the disadvantages of traditional diagnoses such as sensitivity, spatial resolution, short half-decay time and complexity. Therefore, exploring a multifunctional nanocomposite with the combination of their individual modality characteristics has great impact on preoperative imaging and intraoperative diagnosis of cancer. In our study, mesoporous silica gadolinium-loaded gap-enhanced Raman tags (Gd-GERTs) specifically for preoperative and intraoperative imaging are designed and their imaging capability and biosafety are examined. They exhibit strong attenuation property for computed X-ray tomography (CT) imaging, high T1 relaxivity for magnetic resonance (MR) imaging capability and surface-enhanced Raman spectroscopy (SERS) signal with good dispersity and stability, which presents CT/MR/SERS multi-mode imaging performance of the tumor of mice within a given time. Furthermore, in vivo biodistribution and long-term toxicity studies reveal that the Gd-GERTs have good biocompatibility and bio-safety. Therefore, Gd-GERTs are of great potential as a multifunctional nanoplatform for accurate preoperative CT/MRI diagnosis and intraoperative Raman imaging-guide resection of cancers. STATEMENT OF SIGNIFICANCE: Recent advances in molecular imaging technology have provided a myriad of opportunities to prepare various nanomaterials for accurate diagnosis and response evaluation of cancer via different imaging modalities. However, single bioimaging modality is still challenging to overcome the issues such as sensitivity, spatial resolution, imaging speed and complexity for clinicians. In this work, we designed a kind of unique multifunctional nanoprobes with computed X-ray tomography/magnetic resonance/surface-enhanced Raman spectroscopy (CT/MR/SERS) triple-modal imaging capabilities. Multifunctional nanotags offer the capabilities of preoperative noninvasive CT/MR imaging for identification of tumors as well as intraoperative real-time SERS imaging for guidance of complete resection of tumors. These multifunctional nanoprobes show critical clinical significance on the improvement of tumor diagnosis and therapy.

9.
Dermatology ; : 1-9, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31896113

RESUMO

BACKGROUND: Mammalian target of rapamycin (mTOR) inhibitors have been shown to have excellent effects in the management of kaposiform hemangioendothelioma (KHE); however, the mechanism of action is unclear. This study identified the expressions of mTOR pathway-related proteins in different vascular tumors to provide insight into the pathogenesis of KHE. METHODS: We retrospectively reviewed the pathologic specimens of 30 patients (KHE, 15; tufted angioma [TA], 5; infantile hemangioma [IH], 5; and lymphatic malformation [LM], 5). The immunohistochemical expression of mTOR-related proteins tuberous sclerosis complex 2 (TSC2), phosphatase and tensin homologue (PTEN), phosphorylated eukaryotic translation initiation factor 4E binding protein 1 (p-4EBP1), phosphorylated mTOR (p-mTOR), and phosphorylated ribosomal protein S6 kinase B1 (p-P70S6K) were analyzed using Image-Pro Plus software. KHE had the following pattern of expression in the spindle vascular endothelial cells: TSC2 (-); PTEN (-); p-4EBP1 (+); p-mTOR (+); and p-P70S6K (+). RESULTS: All 3 patients treated with sirolimus had good responses. The TA results were similar to KHE with no significant differences (p-4EBP1: p = 0.0687; p-mTOR: p = 0.0832). The expressions of TSC2, PTEN, p-4EBP1, p-mTOR, and p-P70S6K were negative or weakly positive in IH with a statistically significant difference compared to KHE (p-4EBP1: p < 0.001; p-mTOR: p < 0.001; p-P70S6K: p < 0.001). LM had no significant differences when compared to KHE. CONCLUSIONS: The absence of TSC2 and PTEN caused abnormal activation of the mTOR signaling pathway and may be involved in the pathogenesis of KHE. The expression of mTOR-related proteins in TA and LM was similar to KHE, unlike IH. The KHE pattern of expression [PTEN (-), TSC2 (-), p-mTOR (+), p-P70S6K (+), and p-4EBP1 (+)] suggested that sirolimus may be a good therapeutic choice.

10.
Surg Endosc ; 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31953725

RESUMO

BACKGROUND: Numerous studies have shown that the short-term efficacy of three-dimensional (3D) laparoscopic radical gastrectomy (LG) is comparable to that of two-dimensional (2D)-LG. Whether 3D-LG affects the recurrence patterns of gastric cancer (GC) patients has not been investigated. METHODS: From January 2015 to April 2016, a total of 419 patients were recruited for a phase III clinical trial (NCT02327481), which compared the short-term outcomes between the 2D and 3D groups. The long-term efficacy including recurrence patterns was compared between the 2D and 3D groups in this retrospective study. Multivariate analyses were performed to determine whether 3D-LG affects the recurrence patterns. RESULTS: Ultimately, 401 patients were analyzed (197 in the 2D-LG group and 204 in the 3D-LG group), and no differences were observed in the clinicopathological data between the two groups. There were no significant differences between the two groups in the recurrence types, first recurrence time or recurrence-free survival (RFS) (all p > 0.05). According to the 7th American Joint Committee on Cancer tumor-node-metastasis (TNM) staging system, both groups were stratified into pathological stages I, II, and III. The stratified analysis showed no significant differences in RFS or overall survival (OS) among patients in each subgroup (all p > 0.05). The multivariate analysis of RFS showed that tumor diameter, pTNM stage, lymphovascular invasion, and adjuvant chemotherapy were independent factors (all p < 0.05). The multivariate analysis of post-recurrence survival (PRS) showed that adjuvant chemotherapy was an independent protective factor (p = 0.043). CONCLUSIONS: 3D-LG for GC did not differ significantly from 2D-LG in the effects on 3-year recurrence patterns, RFS and OS, which provides more tumor-related evidence for 3D technology. And due to the technological similarity, it may have certain reference value for robotic-assisted gastrectomy. Further multicenter, large-scale clinical trials are warranted.

11.
BMC Cancer ; 20(1): 11, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31906893

RESUMO

BACKGROUND: We sought to investigate the prognostic value of complete blood count (CBC)-based biomarkers for patients with resectable gastric cancer (GC). METHODS: Patients with GC who underwent primary surgical resection between December 2008 and December 2013 were included. The estimated area under the curve (AUC) and multivariate Cox regression models were used to identify the best CBC-based biomarker. Time-dependent receiver operating characteristic (t-ROC) curve analysis was used to predict overall survival and compare the prognostic impact. RESULTS: In the 1810 patients analyzed, the median follow-up period was 51.0 months (range 1-101 months). Based on multivariate analysis, the lymphocyte-monocyte ratio (LMR) and hemoglobin (Hb) level were independent prognostic factors (both P < 0.05). Based on the LMR and Hb level, we established the CBC-based inflammatory score (CBCS). A higher CBCS was associated with older age, female sex, higher American Society of Anesthesiologists (ASA) score, proximal tumor location, larger tumor size, later stage and vascular involvement (all P < 0.05). Univariate analyses showed that a higher CBCS was also associated with worse overall survival (OS), which was consistent in each stage (all P < 0.05). Multivariate analysis revealed that the CBCS was a significant independent biomarker (P < 0.05). The AUC for the CBCS (0.627) was significantly higher than the AUCs for the LMR (0.573) and Hb level (0.605) (both P < 0.05). Furthermore, the t-ROC curve of the CBCS was superior to that of the prognostic nutritional index (PNI), systemic immune-inflammation index (SII), modified Glasgow prognostic score (mGPS) and C-reactive protein/albumin ratio (CRP/Alb) throughout the observation period. CONCLUSION: The preoperative LMR and Hb level were optimal CBC-based biomarkers for predicting OS in GC patients after curative resection. Based on the LMR and Hb, we developed a novel and easily obtainable prognostic score called the CBCS, which may improve the prediction of clinical outcomes.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31901181

RESUMO

Purely organic materials showing room temperature phosphorescence (RTP) and ultralong RTP (OURTP) have recently attracted much attention. However, it is challenging to integrate circularly polarized luminescence (CPL) into RTP/OURTP. Here, we show a strategy to realize CPL-active OURTP (CP-OURTP) by binding an achiral phosphor group directly to the chiral center of an ester chain. Engineering of this flexible chiral chain enables efficient chirality transfer to carbazole aggregates, resulting in strong CP-OURTP with a lifetime of over 0.6 s and dissymmetry factor of 2.3×10-3 after the conformation regulation upon photo-activation. The realized CP-OURTP is thus stable at room temperature but can be deactivated quickly at 50 °C to CP-RTP with high CPL stability during the photo-activation/thermal-deactivation cycles. Based on this extraordinary photo/thermal-responsive and highly reversible CP-OURTP/RTP, a CPL-featured lifetime-encrypted combinational logic device has been successfully established.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31995465

RESUMO

A pink-pigmented, Gram-negative, rod-shaped, obligate aerobic bacterial strain, MIMD6T, was isolated from biological soil crusts in PR China. Cells grew at 20-37 °C (optimum, 30 °C), at pH 6-8 (optimum, pH 7) and with 0-1 % (w/v) NaCl (optimum, 0 %). Strain MIMD6T could use methanol or formate as a sole carbon source to grow, and carried methanol dehydrogenase genes mxa F and xox F, supporting its methylotrophic metabolism. The respiratory quinone was ubiquinone Q-10, the major fatty acids were C18 : 1ω7c (87.3 %), and the major polar lipids were diphosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, one unknown aminolipid and one unidentified glycolipid. The results of phylogenetic analyses based on the sequences of the 16S rRNA gene, seven housekeeping genes (dna K, rec A, rim O, rpI K, rpm G, rps R and rpo B) and methanol dehydrogenase genes indicated that strain MIMD6T formed a phylogenetic linage with members of the genus Methylobacterium. Strain MIMD6T was most closely related to Methylobacterium isbiliense DSM 17168T and Methylobacterium nodulans LMG 21967T with 16S rRNA gene sequence similarities of 95.7 and 95.2 %, respectively. The genomic DNA G+C content calculated via draft genome sequencing was 73.0 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strain MIMD6T and the type strains of other Methylobacterium species were 70.7-82.0 and 24.6-30.0 %, respectively. Based on phenotypic, chemotaxonomic and phylogenetic characteristics, strain MIMD6T represents a novel species of the genus Methylobacterium, for which the name Methylobacterium crusticola sp. nov. is proposed. The type strain is MIMD6T (=KCTC 52305T=MCCC 1K01311T).

14.
FASEB J ; 34(1): 720-734, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914611

RESUMO

Confusion persists over pathogenesis of spondylolysis. To confirm pathogenicity of the previously identified causative mutation of spondylolysis and investigate the genetic etiology, we generate a new mouse line harboring D673V mutation in the Slc26a2 gene. D673V mutation induces delayed endochondral ossification characterized by transiently reduced chondrocyte proliferation in mice at the early postnatal stage. Adult D673V homozygotes exhibit dysplastic isthmus and reduced bone volume of the dorsal vertebra resembling the detached vertebral bony structure when spondylolysis occurs, including the postzygopophysis, vertebral arch, and spinous process, which causes biomechanical alterations around the isthmic region of L4-5 vertebrae indicated by finite element analysis. Consistently, partial ablation of Slc26a2 in vertebral skeletal cells using Col1a1-Cre; Slc26a2 fl/fl mouse line recapitulates a similar but worsened vertebral phenotype featured by lamellar isthmus. In addition, when reaching late adulthood, D673V homozygotes develop an evident bone-loss phenotype and show impaired osteogenesis. These findings support a multifactorial etiology, involving congenitally predisposed isthmic conditions, altered biomechanics, and age-dependent bone loss, which leads to SLC26A2-related spondylolysis.

15.
Neuroendocrinology ; 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31940636

RESUMO

PURPOSE: To evaluate whether the European Neuroendocrine Tumor Society (ENETS) system or the 8th American Joint Committee on Cancer (AJCC) staging manual are suitable for gastric neuroendocrine carcinomas and/or mixed adenoneuroendocrine carcinomas (G-NECs/MANECs). METHODS: Patients in the a multicentric series with G-NEC/MANEC who underwent curative-intent surgical resection for a primary tumor were included. An optimal staging system was proposed base on analysis of the T and N status and validated by the SEER database. RESULTS: Compared with the ENETS system, the survival curves of the T category and N category in the 8th AJCC system were better separated and distributed in a more balanced way, but the survival curves of T2 vs T3, N0 vs N1, and N3a vs N3b overlapped. For the T category, the 8th AJCC T category was modified by combining T2 and T3, which was consistent with the T category in the 6th AJCC manual for GC. For the N category, the optimal cut-off values of metastatic lymph nodes using X-tile were also similar to those of the N category in the 6th AJCC system. The Kaplan-Meier plots of the 6th AJCC system showed statistically significant differences between individual substages. Compared with the other two classifications, the 6th AJCC system also showed superior prognostic stratification. Similar results were obtained in both multicentric and SEER validation sets. CONCLUSIONS: Compared to the 8th AJCC and ENETS systems, the 6th AJCC staging system for GC is more suitable for G-NEC/MANEC and can be adopted in clinical practice.

16.
Biochem Biophys Res Commun ; 522(3): 743-748, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31791581

RESUMO

Rheumatoid arthritis is a chronic and systemic autoimmune disease, which affects approximately 1% of the adult population worldwide. The present study investigated the therapeutic effect of theacrine (TC) on arthritis and its mechanisms in Freund's incomplete adjuvant (FIA)-induced SD rats. Rats were randomly divided into 5 groups: i) healthy control; ii) model; iii) positive control with methotrexate (MTX); iv) treatment with 12.5 mg/kg TC; and v) treatment with 25.0 mg/kg TC. The apparent scores, including changes in body weights, degree of paw swelling and arthritis indicators, were analyzed to evaluate the anti-chronic inflammatory effect of TC. The levels of interleukin (IL)-6 and transforming growth factor-ß (TGF-ß) in serum were measured by enzyme-linked immunosorbent assay. The protein and RNA expression levels of the critical factors in rats were measured to elucidate the mechanisms responsible for chronic inflammation and to verify molecular indexes of chronic inflammatory conditions. TC notably suppressed the severity of FIA-induced rat by attenuating the apparent scores, animal weight and inflammatory indexes in the 25 mg/kg TC group compared with the FIA rat model. Furthermore, TC significantly decreased the levels of IL-6 and increased the levels of TGF-ß. Histopathological examinations indicated that TC rescued the synovial hyperplasia and inflammatory cell infiltration in joint tissues. In addition, TC enhanced TGF-ß-mediated shifts in inflammatory marker expression in joint tissue. Overall, the present study demonstrated that TC exerted a superior anti-arthritic effect via the suppression of IL-6 and the activation of TGF-ß by the TGF-ß/SMAD pathway.

17.
Cancer Lett ; 471: 38-48, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-31811909

RESUMO

The biological functions of circular RNAs (circRNAs) in gastric cancer (GC) remain largely unexplored. Here, we identified that circ-RanGAP1 was significantly upregulated in both GC tissues and exosomes from the plasma of GC patients. High circ-RanGAP1 expression was closely associated with an advanced TNM stage, lymph node metastases, and worse survival. Inhibition of circ-RanGAP1 decreased GC cell invasion and migration in vitro. Overexpression of circ-RanGAP1 had the opposite effect. Additionally, circ-RanGAP1 silencing remarkably suppressed tumor growth and metastasis of GC in vivo. Mechanistically, circ-RanGAP1 sponged miR-877-3p to upregulate VEGFA expression. Overexpression of miR-877-3p reversed the biological functions mediated by circ-RanGAP1 in GC cells. Interestingly, we demonstrated that circ-RanGAP1 was upregulated in plasma exosomes from preoperative GC patients. More importantly, the plasma exosomes derived from these patients enhanced the migration and invasion potential of GC cells. Overall, the circ-RanGAP1-mediated miR-877-3p/VEGFA axis promotes GC progression. Our findings suggest that circ-RanGAP1 might act as a potential prognostic biomarker and therapeutic target for GC treatment.

18.
Mol Biotechnol ; 62(1): 56-66, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31749084

RESUMO

DNA cloning is the basic step for different fields of life science, and many efforts have been made to simplify this procedure. In this study, we report two general purpose plasmids (pGP), pGP-XB2E and pGP-B2E, for rapid and cost-effective construct of basic clones. The BciVI and XcmI cleavage sites are designed in pGP-XB2E to test plasmid linearization efficiency. The plasmid has better linearization efficiency by using BciVI which could almost completely digest 2 µg plasmid in 10 min with only one-tenth the recommended enzyme concentration. In order to further optimize the pGP-XB2E, a new plasmid, pGP-B2E, which removed XcmI cleavage site was designed. This vector is highly efficient for cloning PCR products up to 1812 bp, and the number of colonies was about five times that of pGP-XB2E. In addition to TA cloning, blunt-end PCR products with T ended in the primer could be positively linked to the T-vector pGP-B2E without A-tailing treatment (TB cloning). Moreover, as an entry vector, pGP-B2E was also compatible for gateway recombination reaction without frameshift mutations. In general, this vector provides a universal, quick, and cost-efficient method for basic molecular cloning.

19.
Angew Chem Int Ed Engl ; 59(5): 2039-2043, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31693789

RESUMO

The stereodivergent iridium-catalyzed allylic alkylation and fluorination of acyclic ketones is described. α-Pyridyl-α-fluoroketones with vicinal tertiary and quaternary stereocenters were obtained in moderate to excellent yields and stereoselectivities. Distinct from known stereodivergent synthesis, for which two different chiral catalysts are required in general, herein we report a sequence-dependent stereodivergent synthesis. With only a single chiral Ir catalyst, all four possible stereoisomers of the products were prepared from the same starting materials by simply adjusting the sequence of asymmetric allylic alkylation and fluorination and varying the absolute configuration of the Ir catalyst.

20.
J Chromatogr A ; 1609: 460448, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31421793

RESUMO

In this work, we reported a simple two-step method for the synthesis of magnetic mesoporous epoxy resin (MMER), including one-pot template-free hydrothermal synthesis of nanoscale amine-functionalized magnetic nanoparticles (MN-NH2) and initiator-free ring-opening polymerization of epoxy resin. The resultant MMER was characterized in detail by transmission electron microscope (TEM), Fourier transform-infrared (FT-IR) spectra, X-ray photoelectron spectroscopy (XPS), thermogravimetic analysis (TGA) and magnetization curves. These results demonstrated successful synthesis of MMER with sufficient magnetic property and excellent thermal stability. The epoxy resin was covalent bonding MN-NH2 on and synthesized by hydrophobic monomers, so the MMER exhibited excellent adsorption quantity for hydrophobic bile acids. The MMER was used as magnetic solid-phase extraction (MSPE) sorbent, and combined with liquid chromatography-tandem mass spectrometry to extract and monitor 11 kinds of bile acids from serum sample. The proposed MSPE combined with LC-MS/MS method exhibited low limit of detection between 0.1 and 5 ng mL-1. In blank serum sample, 9 kinds of bile acids were detected, and ranged from -2.29 ng mL-1 to 6.86 ng mL-1. In standard addition recovery test, the recovery values of detectable bile acids ranged 102.4% to 108.5%, 96.0% to 104.0% and 82.3% to 103.3% when spiked with 0.2, 2.0 and 20 ng mL-1, respectively. The intra- and inter-day precision (n = 6) ranged 3.7% to 5.9% and 7.0% to 9.5%, respectively. The above results demonstrated that the MSPE combined with LC-MS/MS method was accurate and effective for quantitative determination of bile acids from complex biological samples.

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