The application value of support vector machine model based on multimodal MRI in predicting IDH-1mutation and Ki-67 expression in glioma.

PURPOSE: To investigate the application value of support vector machine (SVM) model based on diffusion-weighted imaging (DWI), dynamic contrast-enhanced (DCE) and amide proton transfer- weighted (APTW) imaging in predicting isocitrate dehydrogenase 1(IDH-1) mutation and Ki-67 expression in glioma. METHODS: The DWI, DCE and APTW images of 309 patients with glioma confirmed by pathology were retrospectively analyzed and divided into the IDH-1 group (IDH-1(+) group and IDH-1(-) group) and Ki-67 group (low expression group (Ki-67 ≤ 10%) and high expression group (Ki-67 > 10%)). All cases were divided into the training set, and validation set according to the ratio of 7:3. The training set was used to select features and establish machine learning models. The SVM model was established with the data after feature selection. Four single sequence models and one combined model were established in IDH-1 group and Ki-67 group. The receiver operator characteristic (ROC) curve was used to evaluate the diagnostic performance of the model. Validation set data was used for further validation. RESULTS: Both in the IDH-1 group and Ki-67 group, the combined model had better predictive efficiency than single sequence model, although the single sequence model had a better predictive efficiency. In the Ki-67 group, the combined model was built from six selected radiomics features, and the AUC were 0.965 and 0.931 in the training and validation sets, respectively. In the IDH-1 group, the combined model was built from four selected radiomics features, and the AUC were 0.997 and 0.967 in the training and validation sets, respectively. CONCLUSION: The radiomics model established by DWI, DCE and APTW images could be used to detect IDH-1 mutation and Ki-67 expression in glioma patients before surgery. The prediction performance of the radiomics model based on the combination sequence was better than that of the single sequence model.

GDSL in Lilium pumilum (LpGDSL) Confers Saline-Alkali Resistance to the Plant by Enhancing the Lignin Content and Balancing the ROS.

In order to explore the response mechanism of Lilium pumilum (L. pumilum) to saline-alkali stress, we successfully cloned LpGDSL (GDSL lipase, Gly-Asp-Ser-Leu) from L. pumilum. The qRT-PCR results indicated that the LpGDSL expression was higher in the leaves of L. pumilum, and the expression of the LpGDSL reached the highest level at 12 h in leaves under 11 mM H2O2, 200 mM NaCl, 25 mM Na2CO3, and 20 mM NaHCO3. The bacteriophage overexpressing LpGDSL was more tolerant than the control under different NaHCO3 contents. Overexpressed and wild-type plants were analyzed for phenotype, chlorophyll content, O2- content, H2O2 content, lignin content, and so on. Overexpressed plants had significantly higher resistance than the wild type and were less susceptible to saline-alkali stress. The yeast two-hybrid and BiFC assays demonstrated the existence of an interaction between LpGDSL and LpBCP. The yeast one-hybrid assay and transcriptional activation assay confirmed that B3 transcription factors could act on LpGDSL promoters. Under saline-alkali stress, L. pumilum will promote the expression of LpGDSL, which will then promotes the accumulation of lignin and the scavenging of reactive oxygen species (ROS) to reduce its damage, thus improving the saline-alkali resistance of the plant.

PS II Subunit P in Lilium pumilum (LpPsbP) Confers Saline-Alkali Resistance to the Plant by Scavenging ROS.

(1) Background: The growth of plants is impacted by salinity and alkali, Lilium pumilum (L. pumilum) is an ornamental plant with strong resistance to salinity and alkali, while the LpPsbP gene is helpful to fully understand the Saline-Alkali tolerance of L. pumilum. (2) Methods: Gene cloning, bioinformatics analysis, expression of fusion protein, determination of physiological indices of plant after Saline-Alkali stress, yeast two-hybrid screening, luciferase complementation assay, chromosome walking to obtain the promoter sequence, and then analyzed by PlantCARE. (3) Results: The LpPsbP gene was cloned and the fusion protein was purified. The transgenic plants had higher Saline-Alkali resistance than the wild type. A total of eighteen proteins interacting with LpPsbP were screened, and nine sites in the promoter sequence were analyzed. (4) Conclusion: Under Saline-Alkali or oxidative stress, L. pumilum will promote the expression of LpPsbP, which will then directly scavenge reactive oxygen species (ROS) in order to protect its photosystem II, reduce its damage, and thus improve the Saline-Alkali resistance of the plant. Moreover, according to some of the literature and the following experiments, two additional speculations are developed on the mechanisms of how two newly found objects, namely jasmonic acid (JA) and FoxO protein, could be involved in ROS scavenging processes were made.

Construction and characterization of thymidine auxotrophic (ΔthyA) recombinant Lactobacillus casei expressing bovine lactoferricin.

BACKGROUND: Lactobacillus casei (L. casei) is well known for its probiotic property in human and animals. Lactoferricin (Lfcin) polypeptide can effectively modulate host immune responses and have antimicrobial activity in vivo and in vitro. In order to develop a food-grade L. casei system constitutively expressing bovine Lfcin, this study constructed a thymidine auxotrophy (ΔthyA) recombinant L. casei. RESULTS: Based on the thymidylate synthase gene (thyA) insert site, LFEC(Lfcin expression cassette)was inserted into L. casei genome through homologous recombination, successfully expressed and could be stably inherited. The recombinant L. casei, ΔthyA L. casei-LFEC, is sensitive to chloramphenicol and limited when cultured without thymine. Meanwhile, ΔthyA L. casei-LFEC has both good antibacterial activity against Escherichia coli and Staphylococcus aureus and antiviral activity against porcine epidemic diarrhea virus (PEDV). CONCLUSIONS: We successfully constructed a recombinant L. casei strain expressing Lfcin, ΔthyA L. casei-LFEC, which could only survive in the presence of thymine, and had excellent antimicrobial and antiviral activity with good genetic stability and sensitivity. This research provides a cost-effective alternative to the antibiotics with additional biological functions and wider applicability prospect. Using ΔthyA as the selectable mark instead of antibiotic to construct genetic engineering L.casei provides a safe and effective approach of feed additives in livestock raising.

DNA in serum extracellular vesicles is stable under different storage conditions.

BACKGROUND: Extracellular vesicles (EVs), including exosomes, microvesicles, and apoptotic bodies, can be secreted by most cell types and released in perhaps all biological fluids. EVs contain multiple proteins, specific lipids and several kinds of nucleic acids such as RNAs and DNAs. Studies have found that EVs contain double-stranded DNA and that genetic information has a certain degree of consistency with tumor DNA. Therefore, if genes that exist in exosomes are stable, we may be able to use EVs genetic testing as a new means to monitor gene mutation. METHODS: In this study, EVs were extracted from serum under various storage conditions (4 °C, room temperature and repeated freeze-thaw). We used western blotting to examine the stability of serum EVs. Then, we extracted DNA from EVs and tested the concentration changing under different conditions. We further assessed the stability of EVs DNA s using polymerase chain reaction (PCR) and Sanger sequencing. RESULTS: EVs is stable under the conditions of 4 °C (for 24 h, 72 h, 168 h), room temperature (for 6 h, 12 h, 24 h, 48 h) and repeated freeze-thaw (after one time, three times, five times). Also, serum DNA is mainly present in EVs, especially in exosomes, and that the content and function of DNA in EVs is stable whether in a changing environment or not. We showed that EVs DNA stayed stable for 1 week at 4 °C, 1 day at room temperature and after repeated freeze-thaw cycles (less than three times). However, DNA from serum EVs after 2 days at room temperature or after five repeated freeze-thaw cycles could be used for PCR and sequencing. CONCLUSIONS: Serum EVs and EVs DNA can remain stable under different environments, which is the premise that EVs could serve as a novel means for genetic tumor detection and potential biomarkers for cancer diagnostics and prognostics.

Identification of the functional domain of the porcine epidemic diarrhoea virus receptor.

Porcine aminopeptidase N (pAPN) is a functional receptor for porcine epidemic diarrhoea virus (PEDV). Although PEDV is known to use the pAPN as the major receptor for cell entry, the crucial domain of the pAPN that interacts with the PEDV is still unknown. In the present study, in order to determine the crucial domain of the pAPN, the extracellular domain of pAPN was divided into three subdomains named SPA, SPB and SPC, based on its secondary structure. Recombinant plasmid pcDNA3.1 expressing SPA, SPB and SPC was constructed and introduced into Madin-Darby canine kidney (MDCK) cells by transfection. Following the detection of PEDV infection in transfected MDCK cells after PEDV challenge, we clearly demonstrated that the SPC subdomain plays a key role in cell entry of PEDV and its expression permits PEDV growth in transfected MDCK cells, while virus propagation can be inhibited by anti-SPC serum, indicating that the SPC subdomain appears to be a crucial functional domain in contributing to efficient PEDV infection.

Ferric reduction oxidase in Lilium pumilum affects plant saline-alkaline tolerance by regulating ROS homeostasis.

Ferric reduction oxidase (FRO) plays important roles in biotic and abiotic stress. However, the function of ferric reduction oxidase from Lilium pumilum in response to NaHCO3 is unknown. Here we report the functional characterization of ferric reduction oxidase 7 in Lilium pumilum (LpFRO7) in stresses. Under NaHCO3 stress, the LpFRO7 overexpression lines exhibited lower accumulation of reactive oxygen species (ROS), higher activities in antioxidant enzyme (CAT, SOD and POD) and ferrite reductase, resulting in improved tolerance compared to the wild type (WT). In order to determine the functional network of LpFRO7, it was confirmed by EMSA assays, Yeast one-hybrid assays and Dual luciferase reporter assays that LpbHLH115 transcription factor can bind to the promoter of LpFRO7. Yeast two-hybrid assays, BiFC, and LCI assays were performed to prove that LpFRO7 can interact with LpTrx. Combining these findings, we concluded that LpFRO7 affects plant saline-alkaline tolerance by regulating ROS homeostasis.

First record of Xenanastatus Bouek (Hymenoptera: Eupelmidae) in China with description of one new species with DNA data.

The genus Xenanastatus Bouek (Hymenoptera: Eupelmidae) is recorded for the first time in China based on a newly described species, X. imbricatius Wu & Peng sp. nov. The new species is described and illustrated based on females from Guangdong province; internal transcribed spacer 2 (ITS2) and partial mitochondrial cytochrome oxidase subunit I (COI) and 28S ribosomal DNA (28S) sequences are provided. The world species of Xenanastatus are differentiated in a key based on females.

Diffusion Kurtosis Imaging for Assessing the Therapeutic Response of Transcatheter Arterial Chemoembolization in Hepatocellular Carcinoma.

Objective: This study aimed to evaluate the therapeutic response of hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE) with diffusion kurtosis imaging (DKI). Methods: Forty-three patients with fifty-nine hepatic cancer nodules were recruited for this study. All patients were treated by TACE. Magnetic resonance imaging (MRI) and DKI (b=0, 800, 1,500, 2,000mm2/s) were performed before and one month after initiating TACE. Patients were classified as either progressing groups or non-progressing groups. Mean kurtosis (MK), mean diffusion (MD), and apparent diffusion coefficient (ADC) values of the tumor tissue were analyzed. Results: Twenty-three HCCs were classified as progressing groups, and thirty-six HCCs were non-progressing groups. After TACE, the values of MD and ADC in non-progressing groups (1.92±0.36×10-3mm2/s, 1.36±0.23×10-3mm2/s) were greater than progressing groups (1.44±0.32× 10-3mm2/s, 1.10±0.23×10-3mm2/s), however, the MK values in non-progressing groups (0.47±0.12) were lower than progressing groups (0.72±0.14). The MK values of tumor among non-progressing patients decreased one month after TACE (0.47±0.12) relative to the preoperative values (0.71±0.12) (P<0.05). In the non-progressing groups, the MD and ADC values of tumor after TACE (1.92±0.36×10-3mm2/s, 1.36±0.23×10-3mm2/s) became higher than their preoperative values (1.44±0.35×10-3mm2/s, 1.09±0.22×10-3mm2/s) (P<0.05). In the progressing groups, the MK, MD, and ADC values of tumor after TACE remained similar before TACE (P>0.05). The sensitivity, specificity, and AUC of the ROC curve for the assessment of HCC progress after TACE by MK (85.2%, 97.5%, and 0.95, respectively) were greater than by ADC (78.6%, 66.5%, and 0.75, respectively) and MD (76.2%, 64.3%, and 0.71, respectively). Conclusions: DKI for assessing the therapeutic response of TACE in HCC shows great promise. MK is more advantageous in the assessment of HCC progress after TACE.

Comparison of diffusion kurtosis imaging versus diffusion weighted imaging in predicting the recurrence of early stage single nodules of hepatocellular carcinoma treated by radiofrequency ablation.

OBJECTIVE: This study aimed to compare the diffusion kurtosis imaging (DKI) versus diffusion weighted imaging (DWI) in predicting the recurrence of early stage single nodules of hepatocellular carcinoma (HCC) treated by radiofrequency ablation (RFA). MATERIALS AND METHODS: A retrospective analysis of 107 patients with early stage single nodules of HCC was performed, all patients treated by RFA. Recurrence rate of HCC was recorded after a median follow-up of 36 months. During follow-up, the data of magnetic resonance imaging (MRI), DWI and DKI were obtained in multiple time points. The predictive values of DWI and DKI were analyzed using ROC curves. RESULTS: The overall recurrence rate was 66.3% (71/107). The sensitivity, specificity, and AUC for ADC, MD and MK after RFA (78.6, 73.3% and 0.842; 85.7, 83.3% and 0.839; 85.7, 96.7% and 0.956) were higher than before RFA (44.3, 53.3% and 0.560; 51.2, 56.7% and 0.543; 43.6, 67.3% and 0.489). The sensitivity, specificity, and AUC for MK after RFA were 85.7, 96.7%, and 0.956, respectively, which were significantly greater than those of ADC (78.6, 73.3% and 0.842; P < 0.05) and MD (85.7, 83.3% and 0.839). CONCLUSIONS: The prediction efficacy of DKI for the recurrence of early stage single nodules of HCC was better than that of DWI. And, MK was the most sensitive predictor among the DKI.