Pharmacokinetics and Pharmacodynamics of Sacubitril/Valsartan in Maintenance Hemodialysis Patients with Heart Failure.

BACKGROUND: Heart failure (HF) is one of the main comorbidities in patients receiving maintenance hemodialysis (HD). Sacubitril/valsartan (SAC/VAL) is widely used in HF patients with reduced ejection fraction (HFrEF) or HF mid-range ejection fraction (HFmrEF). However, the pharmacokinetic (PK) and pharmacodynamic properties of SAC/VAL in HD patients with HF remain uncertain. OBJECTIVES: This study aimed to analyze the efficacy and PK properties of SAC/VAL in HD patients with HFrEF or HFmrEF. METHODS: HD patients with HFrEF or HFmrEF were treated with SAC/VAL 50 or 100 mg twice a day (BID) and the concentrations of valsartan and LBQ657 (active metabolite of SAC) were determined by high-performance liquid chromatography-tandem mass spectrometry during HD and on the days between HD sessions (interval days). N-terminal-pro B-type natriuretic peptide and high-sensitivity troponin T were measured, and left ventricular ejection fraction (LVEF) was evaluated by echocardiography. RESULTS: The mean maximum plasma concentrations (Cmax) of LBQ657 and VAL on the interval days were 15.46 ± 6.01 and 2.57 ± 1.23 mg/L, respectively. Compared with previous values in patients with severe renal impairment and healthy volunteers, these levels both remained within the safe concentration ranges during treatment with SAC/VAL 100 mg BID. Moreover, SAC/VAL significantly improved LVEF in HD patients with HFrEF or HFmrEF (p < 0.05). CONCLUSIONS: HD did not remove the SAC metabolite LBQ657 or VAL in patients with HF. However, SAC/VAL 100 mg BID was safe and effective in patients undergoing HD.

Self-assembly of photosensitive and radiotherapeutic peptide for combined photodynamic-radio cancer therapy with intracellular delivery of miRNA-139-5p.

BACKGROUND: A significant challenge in cancer therapy is to maximize the therapeutic efficacy and minimize the side effects. In the past decade, a lot of nanoparticles have been used as the carriers for efficient drug delivery. METHODS AND RESULTS: This study was to prepare R9 modified with 125I-labeled cRGD and ce6 which self-assembled with miR-139-5p to form nanoparticles (Ce6-R9-125I-RGD-MNPs), and to further take advantage of the enhanced permeability and retention (EPR) effect of radiolabeled nanoparticles to realize the integration of tumor diagnosis and treatment. We successfully synthesized and represented it, saline and serum stability experiments demonstrating good stability. Moreover, Ce6-R9-125I-RGD-MNPs showed superior tumor targeting and the effect of combined photodynamic therapy (PDT) and radiotherapy treatment in vivo and vitro. CONCLUSION: The pathological results further confirmed that the therapeutic doses of Ce6-R9-125I-RGD-MNPs cause pathological changes of tumor tissues while showing minimal toxicity to normal tissues.

Fibronectin 1 activates WNT/ß-catenin signaling to induce osteogenic differentiation via integrin ß1 interaction.

Osteoporosis (OP) is a systemic skeletal disease leading to fragility fractures and is a major health issue globally. WNT/ß-catenin signaling regulates bone-remodeling processes and plays vital roles in OP development. However, the underlying regulatory mechanisms behind WNT/ß-catenin signaling in OP requires clarification, as further studies are required to identify novel alternate therapeutic agents to improve OP. Here we report that fibronectin 1 (FN-1) promoted differentiation and mineralization of osteoblasts by activating WNT/ß-catenin pathway, in cultured pre-osteoblasts. With isobaric tags for relative and absolute quantitation labeling proteomics analysis, we investigated protein changes in bone samples from OP patients and normal controls. FN-1 accumulated in osteoblasts in bone samples from OP patients and age-related OP mice compared to control group. In addition, we observed that integrin ß1 (ITGB1) acts as an indispensable signaling molecule for the interplay between FN-1 and ß-catenin, and that FN-1 expression increased, but ITGB1 expression decreased in osteoblasts during OP progression. Therefore, our study reveals a novel explanation for WNT/ß-catenin pathway inactivation in OP pathology. Supplying of FN-1 and ITGB1 may provide a potential therapeutic strategy in improving bone formation during OP.

BLACAT1 predicts poor prognosis and serves as oncogenic lncRNA in small-cell lung cancer.

Bladder cancer-associated transcript 1 (BLACAT1) is a novel identified long noncoding RNA (lncRNA) in bladder cancer, and has been suggested to function as an oncogenic lncRNA in several types of human cancer. However, its involvement in the progression of small-cell lung cancer (SCLC) remained unknown. The aim of our study was to investigate the clinical value and biological function in SCLC. In our results, BLACAT1 expression was increased in SCLC tissues and cell lines compared with paired adjacent normal tissues and bronchial epithelial cell lines, respectively. In addition, BLACAT1 high-expression was obviously associated with advanced clinical stage, large tumor size, more lymph node metastasis, present distant metastasis, and poor prognosis. Furthermore, multivariate analysis indicated that high-expression of BLACAT1 acted as an independent poor prognostic factor for overall survival in SCLC cases. The loss-of-function studies suggested that of BLACAT1 suppressed SCLC cell proliferation, migration, and invasion, and induced G0/G1 phase arrest. In conclusion, BLACAT1 is associated with the malignant status and prognosis in patients with SCLC, and functions as an oncogenic lncRNA in regulating cell proliferation and motility, suggesting BLACAT1 may act as a potential target for SCLC prevention and treatment.

A novel interaction between ATOH8 and PPP3CB.

ATOH8 is a bHLH transcription factor playing roles in a variety of developmental processes such as neurogenesis, differentiation of pancreatic precursor cells, development of kidney and muscle, and differentiation of endothelial cells. PPP3CB belongs to the catalytic subunit of the serine/threonine phosphatase, calcineurin, which can dephosphorylate its substrate proteins to regulate their physiological activities. In our study, we demonstrated that ATOH8 interacts with PPP3CB in vitro with different approaches. We show that the conserved catalytic domain of PPP3CB interacts with both the N-terminus and the bHLH domain of ATOH8. Although the interaction domain of PPP3CB is conserved among all isoforms of calcineurin A, ATOH8 selectively interacts with PPP3CB instead of PPP3CA, probably due to the unique proline-rich region present in the N-terminus of PPP3CB, which controls the specificity of its interaction partners. Furthermore, we show that inhibition of the interaction with calcineurin inhibitor, cyclosporin A (CsA), leads to the retention of ATOH8 to the cytoplasm, suggesting that the interaction renders nuclear localization of ATOH8 which may be critical to control its activity as transcription factor.

[The Enhancement Research of Magnetic Stirring with Laser Irradiation Aqueous Solution on ICP Source Radiation].

At present, the way to introduce the sample into the inductively coupled plasma atomic emission spectrometry (ICP-AES) light source is still in the form of solution. In order to improve the treatment effect of the aqueous solution and change its physical properties, the surface tension and viscosity under different experimental conditions were measured with magnetic stirring combined with laser irradiation. . The treated samples were introduced into the inductively coupled plasma (ICP) to measure the spectral line intensity, signal-to-background ratio, excitation temperature and electron density emitted by the ICP source. The experimental results showed that: when the magnetic stirrer rotate speed was 1 197 r·min-1, the laser power density was 0.227 6 W·cm-2 and irradiation for 15 min, the surface tension and viscosity of the solution were decreased by 27.85% and 8.66% respectively than those of the untreated solution. As to the element spectral lines of As 188.980 nm, Cd 214.439 nm, Cr 267.716 nm, Cu 324.754 nm, Hg 253.652 nm and Pb 220.353nm: the intensity was enhanced 32.07%, 65.36%, 18.27%, 32.29%, 19.38% and 54.28%; the signal-to-background ratio increased by 25.13%, 60.97%, 18.18%, 27.69%, 21.11% and 48.93%, respectively. The enhancement of the plasma radiation was explained to a certain extent by measuring the excitation temperature and electron density of the plasma. The processing method of the aqueous solution can effectively improve the spectral intensity and signal-to-background ratio of the ICP. Compared with the laser irradiation aqueous solution separately, this method significantly shortened the processing time, improve the efficiency. This method is simple, with no secondary pollution in the treatment of the sample solution, convenient popularization and use.

Gene therapy for hemophilia B with liver-specific element mediated by Rep-RBE site-specific integration system.

Adeno-associated virus (AAV) is a nonpathogenic virus capable of targeting human chromosome 19 for integration at AAVS1 site, and a 16 bp Rep binding element (RBE) sequence of AAV was sufficient for mediating this specific integration in the presence of AAV regulation proteins (Rep). Previously, we cotransduced 2 plasmids, pRBE-CMV-hFIX and pRC, into the AAVS1 transgenic mice by hydrodynamic injection, and a long-term expression of human coagulation Factor IX (hFIX) was observed. The corresponding AAVS1 locus site-specific integrations were verified by nested polymerase chain reaction. In this study, we established a novel hFIX expression plasmid, pRBE-HCR-hAAT-hFIX, driven by a liver-specific promoter by replacing the CMV promoter of pRBE-CMV-hFIX with a humanized promoter consisting of HCR-hAAT. The expression of hFIX in vitro was almost the same in transient transfection of pRBE-CMV-hFIX or pRBE-HCR-hAAT-hFIX. AAVS1-specific integrations were identified both in mice transfected with pRC/pRBE-CMV-hFIX cocktail and pRC/pRBE-HCR-hAAT-hFIX cocktail. However, the expression of hFIX of pRBE-HCR-hAAT-hFIX mice was higher and persisted longer. It achieved more than 1% of normal plasma hFIX concentration and maintained for 240 days. The result suggested that RBE-HCR-hAAT element could improve the expression of hFIX and present potential usage of Rep-RBE site-specific integration in gene therapy for hemophilia B.

[Enhancement effect of double-beam laser processed aqueous solution on ICP emission spectrum].

In order to change the physical properties of aqueous solution and improve the radiation intensity of the ICP emission spectrum, the effects of different laser power density and irradiation time on the surface tension and viscosity of aqueous solution were investigated by using near infrared laser at 976 nm and CO2 laser at 10. 6 µm to irradiate aqueous solution orthogonally, then the enhancement of ICP spectral intensity with processed solution was discussed. The results showed that the surface tension and viscosity of aqueous solution reduced by 42. 13% and 14. 03% compared with the untreated, and the atomization efficiency increased by 51.26% at the laser power density 0. 265 7 W . cm-2 of 976 nm and 0. 206 9 W . cm-2 of CO2 laser with 40 min irradiation time. With the optimized aqueous solution introduced into the ICP source, the spectral line intensity of sample elements As, Cd, Cr, Hg and Pb was enhanced by 46.29%, 94. 65%, 30. 76%, 33.07% and 94. 58% compared to the untreated aqueous solution, while the signal-to-background ratio increased by 43. 84%, 85. 35%, 28. 71%, 34. 37% and 90. 91%, respectively. Plasma temperature and electron density also increased by 5. 94% and 1. 18% respectively. It is obvious that the method of double-beam laser orthogonal irradiation on solution can reduce the surface tension and viscosity of aqueous solution significantly, and raise the radiationintensity of ICP source, and will provide a better condition for detecting the trace heavy metal elements in water samples.

[Study of self-absorption effect on laser-induced metal plasma].

In order to reduce the effect of the spectral line self-absorption on the analysis result in the laser induced plasma and enhance the qualities of spectrum, the spectral information was recorded by the spectral analysis system consisting of a modular multifunctional grating spectrometer and a CCD detector etc., and the electron temperature and electron density of the plasma were measured with the spectroscopic methods. A plane mirror device was used to constraint the laser plasma, and a reasonable explanation was got through comparing the linear evolution under different experimental conditions and measuring the temperature, electronic density and sample evaporation. The result shows that when an appropriate plane mirror device was used to constraint the laser plasma, the axial temperature of the plasma increased and the radial distribution of the plasma becomes uniform; the electron density increased dramatically; however, obviously sample evaporation decreased, which may be the reasons for being able to effectively reduce the level of self-absorption spectral lines. Therefore, the plane mirror device could reduce the self-absorption effect in the laser-induced plasma. This makes it possible to choose a sensitive line that acts as analysis line in the quantitative analysis of the major elements. In other words, this promotes the measurement precision in the laser-induced break-down spectroscopy.

[Enhancement effect of laser-processed aqueous solution on ICP source radiation].

To enhance the intensity of inductively coupled plasma-atomic emission spectrum and improve the detection level of trace heavy metal elements, the surface tension and viscosity of the aqueous solution processed by near-infrared laser at wave-length of 976 nm were studied in the present paper. The influences of the treated solution on the spectral line intensity and signal-to-background ratio of the ICP source were observed. The results showed that when the laser irradiation time was 60 min and the power density was 0.329 6 W x cm(-2), the surface tension and viscosity of the solution decreased by 36.73% and 9.73% respectively compared to the untreated solution. Under the optimum conditions, the aqueous solution treated by the laser irradiation was introduced into the ICP source. By measuring the intensity of emission spectrum of the sample elements, the spectral line intensity of Cd, Cr, Cu, Hg, and Pb was enhanced by about 73.52%, 22.97%, 33.86%, 24.44% and 65.59% compared to the untreated solution, while the signal-to-background ratio increased by 76.03%, 21.74%, 32.17%, 22.68% and 65.32%, respectively. Spectral line intensity and signal-to-background ratio of the ICP source were significantly improved so that the foundation was established for reducing the analysis detection limits. Further more, the surface tension and viscosity of the processed aqueous solution remain the same within 30 minutes standing time with the stable physical properties. This simple and easy method of laser-processed aqueous solution helps improve the detection capabilities of ICP spectrometry.

MicroRNA-7 inhibits tumor growth and metastasis by targeting the phosphoinositide 3-kinase/Akt pathway in hepatocellular carcinoma.

UNLABELLED: MicroRNAs (miRNAs) are known to be involved in carcinogenesis and tumor progression in hepatocellular carcinoma (HCC). Recently, microRNA-7 (miR-7) has been proven to play a substantial role in glioblastoma and breast cancer, but its functions in the context of HCC remain unknown. Here, we demonstrate that miR-7 inhibits HCC cell growth and metastasis in vitro and in vivo. We first screened and identified a novel miR-7 target, phosphoinositide 3-kinase catalytic subunit delta (PIK3CD). Overexpression of miR-7 would specifically and markedly down-regulate its expression. miR-7-overexpressing subclones showed significant cell growth inhibition by G(0) /G(1) -phase cell-cycle arrest and significant impairment of cell migration in vitro. To identify the mechanisms, we investigated the phosphoinositide 3-kinase (PI3K)/Akt pathway and found that Akt, mammalian target of rapamycin (mTOR), and p70S6K were down-regulated, whereas 4EBP1 was up-regulated in miR-7-overexpressing subclones. We also identified two novel, putative miR-7 target genes, mTOR and p70S6K, which further suggests that miR-7 may be a key regulator of the PI3K/Akt pathway. In xenograft animal experiments, we found that overexpressed miR-7 effectively repressed tumor growth (3.5-fold decrease in mean tumor volume; n = 5) and abolished extrahepatic migration from liver to lung in a nude mouse model of metastasis (n = 5). The number of visible nodules on the lung surface was reduced by 32-fold. A correlation between miR-7 and PIK3CD expression was also confirmed in clinical samples of HCC. CONCLUSION: These findings indicate that miR-7 functions as a tumor suppressor and plays a substantial role in inhibiting the tumorigenesis and reversing the metastasis of HCC through the PI3K/Akt/mTOR-signaling pathway in vitro and in vivo. By targeting PIK3CD, mTOR, and p70S6K, miR-7 efficiently regulates the PI3K/Akt pathway. Given these results, miR-7 may be a potential therapeutic or diagnostic/prognostic target for treating HCC.

Role and fate of SP100 protein in response to Rep-dependent nonviral integration system.

Previously, we studied an AAVS1 site-specific non-viral integration system with a Rep-donor plasmid and a plasmid containing adeno-associated virus integration element. Our earlier study focused on the plasmid vector itself, but the cellular response to the system was still unknown. SP100 is a member of the promyelocytic leukemia nuclear bodies. It is involved in many cellular processes such as transcriptional regulation and the cellular intrinsic immune response against viral infection. In this study, we revealed that SP100 inhibited the Rep-dependent nonviral integration. Conversely, transient expression of Rep78 increased the degradation of SP100. This degradation was inhibited by treatment with MG132, an inhibitor of the ubiquitin proteasome. SP100 and Rep78 are both located in the nucleolus, which provides the spatial possibility for their interaction. Rep78 was coimmunoprecipitated with the enhanced green fluorescent protein (EGFP)-SP100 fusion protein but not EGFP, which verified the interaction between Rep78 and SP100. These results have enriched our knowledge about the cellular protein SP100 and Rep-dependent nonviral integration. It may lead to an improvement in the application of Rep-related transgene integration method and in the selection of target cells.

Enhancement effects of flat-mirror reflection on plasma radiation.

Laser-induced breakdown spectroscopy quality can be improved by using a nanosecond Nd:YAG laser pulse to excite soil samples. To investigate how flat-mirror reflection affects the radiation characteristics of laser-induced plasma, emission spectra of sample elements were recorded using a grating spectrometer and photoelectric detection system. Placing a planar mirror vertically on the sample surface (10 mm mirror to plasma-center axis distance) for flat-mirror reflection increased spectral line intensities of Mg, Al, Fe, and Ba by 93.06%, 159.63%, 93.43%, and 94.61%, respectively. Signal-to-noise ratio increased by 17.56%, 40.21%, 31.29%, and 30%. The radiation enhancement mechanism was clarified using measured plasma parameters.

Adeno-associated virus Rep78 restricts adenovirus E1B55K-mediated p53 nuclear exportation.

Inactivation of p53 is needed during adenovirus type 5 DNA replication. E1B55K, an adenovirus early protein, has been reported to interact with p53 and inhibit p53 transactivation. Previous studies have shown that adeno-associated virus (AAV) type 2 could reduce the transforming potential of adenovirus by rescuing p53 from adenovirus-mediated degradation, but the details are not clear yet. We detected the Rep78-p53 interaction by co-immunoprecipitation assay. The co-localization assay revealed that Rep78 inhibits E1B55K-mediated p53 nuclear exportation. However, Rep78 did not detectably influence p53 stability and could not relieve the transcriptional inactivation of p53, as E1B55K could not be replaced from the p53-E1B55K complex by Rep78. Our results reveal a new possible mechanism that AAV-2 Rep78 inhibits adenovirus 5 by relocalizing p53 in the nucleus, which may shed some light on the regulatory mechanism of AAV-2 on its helper virus, adenovirus.

[Effect of ultrasonic cavitation on ICP source radiation intensity].

In order to increase the intensity of inductively coupled plasma radiation and reduce the detection limit of analysis, the experiment studied on the change of surface tension and viscosity of the water samples which were processed by the ultrasonic cavitation, meanwhile the influence of cavitation effect to samples' spectral intensity and signal-to-background ratio was researched. The experimental results showed that the surface tension and viscosity of sample solution initially decreased and then increased as the ultrasonic power and cavitation time monotonously increased, and the minimum value could be achieved at the ultrasonic power of 50W and the cavitation time of 15 minutes. Under the best experiment condition (the ultrasonic power of 50W and the cavitation time of 15 min), the results revealed that the spectral lines intensity of element Al, Cd) Mn, Ni, Pb and Zn were increased around 56.73%, 57.23%, 44.57%, 43.20%, 39.04% and 40.19% than that without cavitation treatment, spectral signal-background ratio increased about 61.54%, 64.86%, 40.95%, 52.27%, 37.84% and 40.84%, respectively. Thus it can be seen that cavitation-processed water solution can improve the quality of Inductively Coupled Plasma-atomic emission spectrum.

[Effect of flat-mirror device on laser-induced plasma radiation characteristics].

To improve the quality of laser-induced breakdown spectroscopy, flat-mirror device was proposed. The effects of flat-mirror device on the radiation characteristics of laser-induced plasma were studied. The experimental results showed that when the device consisted of three flat-mirrors placed around the plasma, the spectral line intensity of Mg, Fe, Ba, Ti and Al increases by about 116.2%, 96.43%, 90.93%, 102.1% and 98.57% than that without flat-mirror device, and the signal-to-noise raises by around 39.17%, 32.48%, 38.07%, 39.95% and 21.30%,respectively. By measuring the plasma parameters, the mechanism of the radiation enhancement obtained with the device consisting of three flat-mirrors was explained. This method was an effective way to improve the detection capacity of LIBS.

[Spectrum diagnostics for the time of pre-sputtering in thin films deposited by magnetron puttering].

Abstract A plasma analysis system comprised of Omni-X300 series grating spectrometer, CCD data acquisition system and optical fiber transmission system was utilized in the present paper to realize the real-time acquisition of plasma emission spectra during the process of radio frequency (RF) magnetron sputtering. The plasma emission spectra produced by NiTa, TiAl ceramic targets and NiA1, TiA1 alloy targets were monitored respectively, in addition, the behavior of analysis lines of Ta I 333.991 nm, Ni I 362.473 nm, Al I 396.153 nm and Ti I 398.176 nm with time was obtained, according to which the time of pre-sputtering of the four kinds of target materials was fixed. At the same time, for the TiAl alloy target as the research object, the influence of different powers and pressures on the time of pre-sputtering was studied.

High-throughput sequencing approach for the identification of lncRNA biomarkers in hepatocellular carcinoma and revealing the effect of ZFAS1/miR-150-5p on hepatocellular carcinoma progression.

Aims: To screen abnormal lncRNAs and diagnostic biomarkers in the progression of hepatocellular carcinoma through high-throughput sequencing and explore the underlying mechanisms of abnormal lncRNAs in the progression of hepatocellular carcinoma. Methods: The transcriptome sequencing was used to analyze the RNA expression profile and identify differentially expressed RNAs. Hub lncRNAs were screened by combining (WGCNA, ceRNA regulatory network, PPI, GO and KEGG analyses, Kaplan-Meier curve analysis, Cox analysis, risk model construction and qPCR). Thereafter, the correlation between the expression of hub lncRNAs and tumor clinicopathological parameters was analyzed, and the hub lncRNAs were analyzed by GSEA. Finally, the effects of hub RNAs on the proliferation, migration and invasion of HepG2 cells were investigated in vitro. Results: Compared with the control group, a total of 610 lncRNAs, 2,593 mRNAs and 26 miRNAs were screened in patients with hepatocellular carcinoma. Through miRNA target prediction and WGCNA, a ceRNA was constructed, comprising 324 nodes and 621 edges. Enrichment analysis showed that mRNAs in ceRNA were involved mainly in cancer development progression. Then, the ZFAS1/miR-150-5p interaction pair was screened out by Kaplan Meier curve analysis, Cox analysis and qPCR analysis. Its expression was related to tumor stage, TNM stage and patient age. ROC curve analysis showed that it has a good predictive value for the risk of hepatocellular carcinoma. GSEA showed that ZFAS1 was also enriched in the regulation of immune response, cell differentiation and proliferation. Loss-of-function experiments revealed that ZFAS1 inhibition could remarkably suppress HepG2 cell proliferation, migration and invasion in vitro. Bioinformatic analysis and luciferase reporter assays revealed that ZFAS1 directly interacted with miR-150-5p. Rescue experiments showed that a miR-150-5p inhibitor reversed the cell proliferation, migration and invasion functions of ZFAS1 knockdown in vitro. Conclusion: ZFAS1 is associated with the malignant status and prognosis of patients with hepatocellular carcinoma, and the ZFAS1/miR-150-5p axis is involved in hepatocellular carcinoma progression.

Exploring the challenge of early gastric cancer diagnostic AI system face in multiple centers and its potential solutions.

BACKGROUND: Artificial intelligence (AI) performed variously among test sets with different diversity due to sample selection bias, which can be stumbling block for AI applications. We previously tested AI named ENDOANGEL, diagnosing early gastric cancer (EGC) on single-center videos in man-machine competition. We aimed to re-test ENDOANGEL on multi-center videos to explore challenges applying AI in multiple centers, then upgrade ENDOANGEL and explore solutions to the challenge. METHODS: ENDOANGEL was re-tested on multi-center videos retrospectively collected from 12 institutions and compared with performance in previously reported single-center videos. We then upgraded ENDOANGEL to ENDOANGEL-2022 with more training samples and novel algorithms and conducted competition between ENDOANGEL-2022 and endoscopists. ENDOANGEL-2022 was then tested on single-center videos and compared with performance in multi-center videos; the two AI systems were also compared with each other and endoscopists. RESULTS: Forty-six EGCs and 54 non-cancers were included in multi-center video cohort. On diagnosing EGCs, compared with single-center videos, ENDOANGEL showed stable sensitivity (97.83% vs. 100.00%) while sharply decreased specificity (61.11% vs. 82.54%); ENDOANGEL-2022 showed similar tendency while achieving significantly higher specificity (79.63%, p < 0.01) making fewer mistakes on typical lesions than ENDOANGEL. On detecting gastric neoplasms, both AI showed stable sensitivity while sharply decreased specificity. Nevertheless, both AI outperformed endoscopists in the two competitions. CONCLUSIONS: Great increase of false positives is a prominent challenge for applying EGC diagnostic AI in multiple centers due to high heterogeneity of negative cases. Optimizing AI by adding samples and using novel algorithms is promising to overcome this challenge.

The 156KELK159 tetrapeptide of HIV-1 integrase is critical for lentiviral gene integration.

HIV-1 integrase (HIV-1 IN), a key element of HIV-1-derived lentiviral vectors, is crucial for the stable maintenance of the vector gene by inserting them into host genome. HIV-1 IN has been found to have functions other than integration, such as involving in virion morphology, viral DNA synthesis and viral DNA nuclear import. In our study, the yeast two-hybrid assay identified a tetrapeptide 156KELK159 in HIV-1 IN that was crucial for HIV-1 IN and Daxx interaction. To investigate the functions of the tetrapeptide 156KELK159 of the HIV-1 IN, both the wild type HIV-1 IN and a mutant without 156KELK159 were used to package the EGFP reporter gene contained lentivirus. p24 based titer assay revealed that deleting the tetrapeptide did not affect virus packaging. The result was verified by quantitative real time PCR with viral specific primers. But the 156KELK159 was crucial for lentiviral gene integration. Deleting the tetrapeptide made the percentage of cells expressing the reporter gene significantly decreased and did not affect the level of DNA entered into the cells or nucleus. Real time reverse transcription PCR and FACS were used to detect the lentiviral report gene expression in infection maintaining cells and revealed 156KELK159 did not affect lentiviral vector gene expression. Our results may shed light on the regulatory mechanism of gene integration of lentivirus.