Objective To establish and validate a multimodal MRI radiomics model based on intratumoral and peritumoral heterogeneity for prediction of spatial pattern of locally recurrent high-grade gliomas(HGGs).Methods A retrospective analysis was conducted on the clinical and imaging data of all HGGs patients who underwent maximum safe resection followed by postoperative radiotherapy combined with temozolomide treatment and experienced in local recurrence in Army Medical Center of PLA from 2012 to 2021.Two radiologists independently assessed the spatial patterns of locally recurrence HGGs through continuous follow-up MRI data,and primarily categorized the pattern into intra-resection cavity recurrence and extra-resection cavity recurrence.The subjected patients were randomly divided into a training set and a validation set in a 7∶3 ratio.In the training set,Pearson or Spearman correlation analysis and least absolute shrinkage and selection operator(LASSO)analysis were employed to screen radiomic features within the intratumoral and peritumoral regions,as well as to calculate radiomic scores.A radiomics model was established using logistic regression analysis.The performance of the model was assessed using calibration curves,Hosmer-Lemeshow goodness-of-fit test,and the area under the receiver operating characteristic curve(AUC).Validation of the model was performed in the validation set.Results A total of 121 patients with locally recurrent HGGs were enrolled in this study,including 54 in intra-resection cavity recurrence group and 67 in extra-resection cavity recurrence group.Among them,84 were assigned into the training set and 37 into the validation set.In the training set,the radiomics score for the extra-resection cavity recurrence group was 0.424(0.278,0.573),which was higher than that for the intra-resection cavity recurrence group[-0.030(-0.226,0.248),P<0.001].In the validation set,the radiomics score for the extra-resection cavity recurrence group was 0.369(0.258,0.487),which was higher than that for the intra-resection cavity recurrence group[0.277(0.103,0.322),P=0.033].The established radiomics model exhibited good calibration and performed well in predicting spatial recurrence patterns,with an AUC value of 0.844(95%CI:0.749～0.914)in the training set and 0.706(95%CI:0.534～0.844)in the validation set.Conclusion Our multimodal radiomics model combined with intratumoral and peritumoral heterogeneity can predict the spatial pattern of locally recurrent HGGs,providing a basis for individualized treatment of HGGs.

Objective To evaluate the predictive value of T2-fluid attenuated inversion recovery (FLAIR)signal suppression rate for the short arm of chromosome 1 and long arm of chromosome 19 (1p/19q)molecular features in lower-grade gliomas (LGG),and to construct and verify the predictive model based on magnetic resonance imaging (MRI)tumor features and T2-FLAIR signal suppression rate.Methods Clincal and imaging data of the patients with pathologically confirmed supratentorial LGG (WHO grade 2～3)in our medical center from 2017 to 2021 were collected and retrospectively analyzed.According to the results of postoperative molecular pathology,they were divided into 1 p/19q-codeleted (1 p/19q-Codel)and 1 p/19q-noncodeleted (1 p/19q-Noncodel)groups.MRI tumor features were blindly assessed by 2 neuroradiologists.Five circular regions of interest were respectively delineated in the tumor area and the normal-appearing white matter in contralateral semioval center using the hot-spot method in order to calculate the T2-FLAIR signal suppression rate.The differences of clinical features,MRI tumor features and T2-FLAIR signal suppression rate were analyzed between the 2 groups.Univariate and multivariate logistic regression analyses were used to screen independent predictors and constructa predictive model and nomogram.Receiver operating characteristic (ROC)curve,calibration curve and Hosmer-Lemeshow test were applied to assess the model performance,and the model was internally validated by bootstrap method.Results A total of 146 supratentorial LGG patients were enrolled,including 68 being assigned into the 1 p/19q-Codel group and 78 into the 1 p/19q-Noncodel group.The T2-FLAIR signal suppression rate was 0.43 (0.28,0.62)in the 1 p/19q-Noncodel group,which was significantly higher than that in the 1 p/19q-Codel group[0.29 (0.24,0.35),P<0.001].Multivariate logistic regression analysis showed that T2-FLAIR signal suppression rate>0.374 (P<0.001),cortex infiltration (P=0.001) and calcification (P=0.004) were independent predictors for 1 p/19q status.The AUC value of T2-FLAIR signal suppression rate>0.374 in predicting 1 p/19q-Noncodel was 0.720,the sensitivity was 60.26％ and the specificity was 83.82％.DeLong test indicated that T2-FLAIR signal suppression rate>0.374 was more effective than T2-FLAIR mismatch sign in predicting 1 p/19q molecular features (P<0.001).ROC curve analysis suggested that the predictive model established by T2-FLAIR signal suppression rate>0.374 combined with cortex infiltration and calcification had good performance,with an AUC value of 0.808,and the AUC value verified internally by bootstrap method was 0.807.At the same time,the calibration and goodness of fit of the model were good.Conclusion T2-FLAIR signal suppression rate can be used as a quantitative imaging marker to predict 1 p/19q-Noncodel LGG.The predictive model with T2-FLAIR signal suppression rate>0.374 combined with cortex infiltration and calcification can effectively predict 1 p/19q molecular features.

Aim To investigate the role of autophagy and its mechanism in Raji cell death induced by arse-nic trioxide. Methods Transmission electron micros-copy ( SEM) and MDC fluorescence staining were used to observe autophagy. MTT colorimetry was employed to assay the cellular proliferating activity. Cell apopto-sis and cell cycle analysis were performed using FITC-Annexin-V/PI double staining and flow cytometry ( FCM) . The expressions of LC3 and the conversion of LC3-I to LC3-II were measured by western bloting. The expression of bcl-2 mRNA and p53 mRNA were detected by reverse transcription-polymerase chain re-action ( RT-PCR ) . Results Arsenic trioxide could obviously inhibit the proliferation of Raji cells, arrest the cells at G2/M phase and induce apoptosis. Mean-while, arsenic trioxide markedly inhibited the expres-sion of bcl-2 mRNA and enhanced the expression of p53 mRNA in Raji cells. Arsenic trioxide also induced autophagy synchronously which paralleled with the in-duction of apoptosis in Raji cells, and 3-MA, an auto-phagy inhibitor, was able to reverse the arsenic triox-ide-activated autophagic activity, up-regulate bcl-2, down-regulated p53 expression and suppress the lethal effect of arsenic trioxide on Raji cells to reduce their sensitivity to arsenic trioxide. In contrast, the Rapamy-cin, an autophagy inducer, possessed the completely opposite effects on Raji cells compared with 3-MA. Conclusions The apoptosis and autophagic cell death are coexistent in arsenic trioxide-triggered death of Raji lymphoma cells, and Bcl-2 and p53 may play a key regulating role in this process.

This article summarizes the present researches on biology of human Demodex about the methods of examination,morphology of adult parasite,biological habits and characteristics,and in vitro survival.