Novel electromagnetic navigation bronchoscopy system for the diagnosis of peripheral pulmonary nodules: a prospective, multicentre study.

BACKGROUND: Traditional electromagnetic navigation bronchoscopy (ENB) is a real-time image-guided system and used with thick bronchoscopes for the diagnosis of peripheral pulmonary nodules (PPNs). A novel ENB that could be used with thin bronchoscopes was developed. This study aimed to evaluate the diagnostic yield and the experience of using this ENB system in a real clinical scenario. METHODS: This multicentre study enrolled consecutive patients with PPNs adopting ENB from March 2019 to August 2021. ENB was performed with different bronchoscopes, ancillary techniques and sampling instruments according to the characteristics of the nodule and the judgement of the operator. The primary endpoint was the diagnostic yield. The secondary endpoints included the diagnostic yield of subgroups, procedural details and complication rate. RESULTS: In total, 479 patients with 479 nodules were enrolled in this study. The median lesion size was 20.9 (IQR, 15.9-25.9) mm. The overall diagnostic yield was 74.9% (359/479). A thin bronchoscope was used in 96.2% (461/479) nodules. ENB in combination with radial endobronchial ultrasound (rEBUS), a guide sheath (GS) and a thin bronchoscope was the most widely used guided method, producing a diagnostic yield of 74.1% (254/343). The median total procedural time was 1325.0 (IQR, 1014.0-1676.0) s. No severe complications occurred. CONCLUSION: This novel ENB system can be used in combination with different bronchoscopes, ancillary techniques and sampling instruments with a high diagnostic yield and safety profile for the diagnosis of PPNs, of which the combination of thin bronchoscope, rEBUS and GS was the most common method in clinical practice. TRIAL REGISTRATION NUMBER: NCT03716284.

Endometriosis-targeted MRI imaging using bevacizumab-modified nanoparticles aimed at vascular endothelial growth factor.

Endometriosis is a tumor-like disease with high recurrence. In this case, the accurate imaging-based diagnosis of endometriosis can help clinicians eradicate it by improving their surgical plan. However, although contrast agents can improve the visibility of the tissue of interest in vivo via magnetic resonance imaging (MRI), the lack of biomarkers in endometriosis hinders the development of agents for its targeted imaging and diagnosis. Herein, aiming at the enriched vascular endothelial growth factor (VEGF) in endometriosis, we developed a targeting MRI contrast agent modified with bevacizumab, i.e., NaGdF4@PEG@bevacizumab-Cy5.5 nanoparticles (NPBCNs), to detect endometriosis. NPBCNs showed negligible cytotoxicity and high affinity towards VEGF in endometrial cells in vitro. Furthermore, NPBCNs generated a strong signal enhancement in vivo in endometriosis lesions in rats in T1-weighted images via MRI at 3 days post-injection, as confirmed by the histopathological staining results and fluorescence imaging on the same day. Our approach can enable NPBCNs to target endometriosis effectively, thus avoiding missed diagnoses.

Central nervous system efficacy of rezivertinib (BPI-7711) in advanced NSCLC patients with EGFR T790M mutation: A pooled analysis of two clinical studies.

BACKGROUND: Rezivertinib (BPI-7711) is a novel third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) which revealed the systematic and central nervous system (CNS) antitumor activities for EGFR T790M-mutated advanced NSCLC in previous clinical studies and is further analyzed here. METHODS: Eligible patients from the previous phase I and phase IIb studies of rezivertinib were included for pooled analysis. Post-progressive patients who received a prescribed dosage (≥180 mg) of rezivertinib orally once daily were included in full analysis set (FAS), while those with stable, asymptomatic CNS lesions, including measurable and non-measurable ones at baseline were included in CNS full analysis set (cFAS). Patients with measurable CNS lesions were included in CNS evaluable for response set (cEFR). BICR-assessed CNS objective response rate (CNS-ORR), CNS disease control rate (CNS-DCR), CNS duration of response (CNS-DoR), CNS progression-free survival (CNS-PFS), and CNS depth of response (CNS-DepOR) were evaluated. RESULTS: 355 patients were included in FAS, among whom 150 and 45 patients were included in cFAS and cEFR. This pooled analysis showed the CNS-ORR was 32.0% (48/150; 95% CI: 24.6-40.1%) and the CNS-DCR was 42.0% (63/150; 95% CI: 34.0-50.3%) in cFAS, while that in cEFR were 68.9% (31/45; 95% CI: 53.4-81.8%) and 100% (45/45; 95% CI: 92.1-100.0%). In cEFR, the median CNS-DepOR and the mean of CNS-DepOR were -52.0% (range: -100.0 to 16.1%) and -46.8% (95% CI: -55.5 to -38.1%). In cFAS, the median CNS-DoR and CNS-PFS were 13.8 (95% CI: 9.6-not calculable [NC]) and 16.5 (95% CI: 13.7-NC) months. CONCLUSIONS: Rezivertinib demonstrated encouraging clinical CNS efficacy among advanced NSCLC patients with EGFR T790M mutation and CNS metastases.

Chinese expert consensus on interventional diagnosis and management of acquired digestive-respiratory tract fistulas (second edition).

Acquired digestive-respiratory tract fistulas occur with abnormal communication between the respiratory tract and digestive tract caused by a variety of benign or malignant diseases, leading to the alimentary canal contents in the respiratory tract. Although various departments have been actively exploring advanced fistula closure techniques, including surgical methods and multimodal therapy, some of which have gotten good clinical effects, there are few large-scale evidence-based medical data to guide clinical diagnosis and treatment. The guidelines update the etiology, classification, pathogenesis, diagnosis, and management of acquired digestive-respiratory tract fistulas. It has been proved that the implantation of the respiratory and digestive stent is the most important and best treatment for acquired digestive-respiratory tract fistulas. The guidelines conduct an in-depth review of the current evidence and introduce in detail the selection of stents, implantation methods, postoperative management and efficacy evaluation.

Evaluation of Inferior Intercavernous Sinus in Patients With Pituitary Microadenoma by Contrast-Enhanced SPACE Imaging.

OBJECTIVE: Inferior intercavernous sinus (iICS) is a venous channel below the pituitary gland. Inferior intercavernous sinus injury is predisposed to cause venous bleeding during dura incision in transsphenoidal surgery for pituitary adenomas. Therefore, this study aimed to perform a radiological assessment of iICS before transsphenoidal surgery for pituitary microadenoma. METHODS: A retrospective evaluation was performed on 156 patients who underwent magnetic resonance imaging examinations in our hospital before endoscopic transsphenoidal surgery for pituitary microadenoma. Both sagittal reformatted and coronal contrast-enhanced (CE) sampling perfection with application optimized contrast using different flip angle evolutions (SPACE) images were interpreted for the presence, shape, and size of the iICS. RESULTS: In CE SPACE, the iICS was identified in 72 patients (46.15%) with pituitary microadenoma. The iICS was appeared as a filiform-shaped hyperintense structure below the pituitary gland on coronal CE SPACE planes and a crescent-shaped hyperintense structure on sagittal CE SPACE planes. The mean ± SD width, depth, and height of iICS were 11.15 ± 3.47 mm, 5.29 ± 1.24 mm, and 1.41 ± 0.19 mm, respectively. CONCLUSIONS: Contrast-enhanced SPACE may serve as a promising technique in evaluating iICS and individualized preoperative planning before transsphenoidal surgery for pituitary microadenoma.

Efficacy and Safety of Rezivertinib (BPI-7711) in Patients With Locally Advanced or Metastatic/Recurrent EGFR T790M-Mutated NSCLC: A Phase 2b Study.

INTRODUCTION: Rezivertinib (BPI-7711) is a novel third-generation EGFR tyrosine kinase inhibitor (TKI) targeting both EGFR-sensitizing mutations and EGFR T790M mutation. This study aimed to evaluate the efficacy and safety of rezivertinib in patients with locally advanced or metastatic/recurrent EGFR T790M-mutated NSCLC. METHODS: Patients with locally advanced or metastatic/recurrent NSCLC with confirmed EGFR T790M mutation who progressed after first-/second-generation EGFR TKI therapy or primary EGFR T790M mutation were enrolled. Patients received rezivertinib at 180 mg orally once daily until disease progression, unacceptable toxicity, or withdrawal of consent. The primary end point was objective response rate (ORR) assessed by blinded independent central review per Response Evaluation Criteria in Solid Tumors version 1.1. Secondary end points included disease control rate (DCR), duration of response, progression-free survival (PFS), overall survival, and safety. This study is registered with Clinical Trials.gov (NCT03812809). RESULTS: A total of 226 patients were enrolled from July 5, 2019, to January 22, 2020. By the data cutoff date on January 24, 2022, the median duration of follow-up was 23.3 months (95% confidence interval [CI]: 22.8-24.0). The ORR by blinded independent central review was 64.6% (95% CI: 58.0%-70.8%), and DCR was 89.8% (95% CI: 85.1%-93.4%). The median duration of response was 12.5 months (95% CI: 10.0-13.9), and median PFS was 12.2 months (95% CI: 9.6-13.9). The median overall survival was 23.9 months (95% CI: 20.0-not calculated [NC]). Among 91 (40.3%) patients with central nervous system (CNS) metastases, the median CNS PFS was 16.6 months (95% CI: 11.1-NC). In 29 patients with more than or equal to one brain target lesion at baseline, the CNS ORR and CNS DCR were 69.0% (95% CI: 49.2%-84.7%) and 100% (95% CI: 88.1%-100%), respectively. Time to progression of CNS was 16.5 months (95% CI: 9.7-NC). Of 226 patients, 188 (83.2%) had at least one treatment-related adverse event, whereas grade more than or equal to 3 occurred in 45 (19.9%) patients. No interstitial lung disease was reported. CONCLUSIONS: Rezivertinib was found to have promising efficacy and favorable safety profile for patients with locally advanced or metastatic/recurrent NSCLC with EGFR T790M mutation.

Analysis of the Dynamic Relationship between Green Economy Efficiency and Urban Land Development Intensity in China.

The improvement of green economic efficiency (GEE) should be realized under reasonable urban land development intensity (ULDI). Improving GEE can also help alleviate the negative externalities of excessive or unreasonable ULDI. Clarifying the interactive response mechanism between GEE and ULDI is a key link in regional sustainable development. Therefore, this paper uses the super-efficiency slack-based model (SBM) method, panel entropy method, and panel vector auto regression model to comprehensively analyze the interactive response relationship between GEE and ULDI in 283 prefecture-level cities in China from 2003 to 2019. This paper finds that: (1) during the research period, both the GEE and ULDI showed a relatively obvious upward trend, which is manifested in the fact that ULDI increased year by year while GEE overall increased in volatility. The growth and evolution trend of ULDI and GEE has the characteristics of interaction and coordination; (2) there is a two-way interactive Granger causality between ULDI and GEE, showing a positive interactive response effect; and (3) both ULDI and GEE have positive inertial growth and self-enhancement mechanisms. In the long run, GEE has a greater impact on the change of ULDI.

Chemical Factory-Guaranteed Enhanced Chemodynamic Therapy for Orthotopic Liver Cancer.

In the field of nanomedicine, there is a tendency of matching designed nanomaterials with a suitable type of orthotopic cancer model, not just a casual subcutaneous one. Under this condition, knowing the specific features of the chosen cancer model is the priority, then introducing a proper therapy strategy using designed nanomaterials. Here, the Fenton chemistry is combined with zinc peroxide nanoparticles in the treatment of orthotopic liver cancer which has a "chemical factory" including that liver is the main place for iron storage, metabolism, and also the main metabolic sites for the majority of ingested substances, guaranteeing customized and enhanced chemodynamic therapy and normal liver cells protection as well. The good results in vitro and in vivo can set an inspiring example for exploring and utilizing suitable nanomaterials in corresponding cancer models, ensuring well-fitness of nanomaterials for disease and satisfactory therapeutic effect.

A Modified Bowel Displacement Technique for Magnetic Resonance Imaging-Guided Focused Ultrasound Surgery in the Treatment of Uterine Fibroids and Adenomyosis.

OBJECTIVE: The clinical application of magnetic resonance imaging-guided focused ultrasound (MRgFUS) surgery for treatment of symptomatic uterine fibroids is often limited because of the bowel between the abdominal wall and uterus. If bowels are in the pathway of sonication path, firstly filling the bladder, then filling the rectum, and emptying the bladder subsequently can be used to avoid them in recent research. The purpose of this study was to evaluate whether the modified bowel displacement technique (rectal filling first and then bladder filling, with or without subsequent bladder emptying) was feasible to create secure acoustic window. METHODS: A total of 78 patients who had undergone MRgFUS treatment for uterine fibroids and adenomyosis from January 2020 to November 2020 were included in this retrospective study. Of the 78 patients, 19 patients were treated using a modified bowel displacement technique, whereas the rest of the patients did not require intestinal displacement. High-intensity focused ultrasound was performed using GE Sightec HDXT 1.5 Tesla MR and ExAblate high-intensity focused ultrasound system. RESULTS: Of the 19 patients requiring bowel displacement techniques, 17 patients successfully completed MRgFUS surgery. Magnetic resonance imaging-guided focused ultrasound surgery was feasible in 4 patients after rectal filling, bladder filling, and subsequent bladder emptying. The others received ablation through the extended bladder because of bowel descending after emptying the bladder. The surgery caused no intestinal or uterine complications and no serious discomfort to the patient. CONCLUSIONS: The modified bowel displacement technique was effective in displacing interposed bowels during MRgFUS treatment to create safe acoustic pathway for ablating uterine fibroids and adenomyosis.

A nomogram strategy for identifying the subclassification of IDH mutation and ATRX expression loss in lower-grade gliomas.

OBJECTIVES: To construct a radiomics nomogram based on multiparametric MRI data for predicting isocitrate dehydrogenase 1 mutation (IDH +) and loss of nuclear alpha thalassemia/mental retardation syndrome X-linked expression (ATRX -) in patients with lower-grade gliomas (LrGG; World Health Organization [WHO] 2016 grades II and III). METHODS: A total of 111 LrGG patients (76 mutated IDH and 35 wild-type IDH) were enrolled, divided into a training set (n = 78) and a validation set (n = 33) for predicting IDH mutation. IDH + LrGG patients were further stratified into the ATRX - (n = 38) and ATRX + (n = 38) subtypes. A total of 250 radiomics features were extracted from the region of interest of each tumor, including that from T2 fluid-attenuated inversion recovery (T2 FLAIR), contrast-enhanced T1 WI, ASL-derived cerebral blood flow (CBF), DWI-derived ADC, and exponential ADC (eADC). A radiomics signature was selected using the Elastic Net regression model, and a radiomics nomogram was finally constructed using the age, gender information, and above features. RESULTS: The radiomics nomogram identified LrGG patients for IDH mutation (C-index: training sets = 0.881, validation sets = 0.900) and ATRX loss (C-index: training sets = 0.863, validation sets = 0.840) with good calibration. Decision curve analysis further confirmed the clinical usefulness of the two nomograms for predicting IDH and ATRX status. CONCLUSIONS: The nomogram incorporating age, gender, and the radiomics signature provided a clinically useful approach in noninvasively predicting IDH and ATRX mutation status for LrGG patients. The proposed method could facilitate MRI-based clinical decision-making for the LrGG patients. KEY POINTS: • Non-invasive determination of IDH and ATRX gene status of LrGG patients can be obtained with a radiomics nomogram. • The proposed nomogram is constructed by radiomics signature selected from 250 radiomics features, combined with age and gender. • The proposed radiomics nomogram exhibited good calibration and discrimination for IDH and ATRX gene mutation stratification of LrGG patients in both training and validation sets.

Harnessing X-Ray Energy-Dependent Attenuation of Bismuth-Based Nanoprobes for Accurate Diagnosis of Liver Fibrosis.

Timely detection of liver fibrosis by X-ray computed tomography (CT) can prevent its progression to fatal liver diseases. However, it remains quite challenging because conventional CT can only identify the difference in density instead of X-ray attenuation characteristics. Spectral CT can generate monochromatic imaging to specify X-ray attenuation characteristics of the scanned matter. Herein, an X-ray energy-dependent attenuation strategy originated from bismuth (Bi)-based nanoprobes (BiF3 @PDA@HA) is proposed for the accurate diagnosis of liver fibrosis. Bi element in BiF3 @PDA@HA can exhibit characteristic attenuation depending on different levels of X-ray energy via spectral CT, and that is challenging for conventional CT. In this study, selectively accumulating BiF3 @PDA@HA nanoprobes in the hepatic fibrosis areas can significantly elevate CT value for 40 Hounsfield units on 70 keV monochromatic images, successfully differentiating from healthy livers and achieving the diagnosis of liver fibrosis. Furthermore, the enhancement produced by the BiF3 @PDA@HA nanoprobes in vivo increases as the monochromatic energy decreases from 70 to 40 keV, optimizing the conspicuity of the diseased areas. As a proof of concept, the strategically designed nanoprobes with energy-dependent attenuation characteristics not only expand the scope of CT application, but also hold excellent potential for precise imaging-based disease diagnosis.

Diffuse Tract Damage Correlates With Global Cognitive Impairment in Cerebral Autosomal Dominant Arteriopathy With Subcortical Infarcts and Leukoencephalopathy: A Tract-Based Spatial Statistics Study.

PURPOSE: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common familial arteriopathy characterized by recurrent lacunar stroke, migraine, and depression. The mechanism of cognitive dysfunction in CADASIL is still uncertain. The aim of this study was to use tract-based spatial statistics (TBSS) to map voxelwise the spatial distribution of brain microstructural change revealed by DTI-derived indices in patients with CADASIL to further study the underlying neuropsychopathological mechanism of CADASIL. METHOD: Twelve patients with CADASIL and 11 age-, sex-matched healthy controls underwent magnetic resonance imaging at 3 T. Then we evaluated DTI-derived indices (fractional anisotropy [FA], mode of anisotropy [MO], mean diffusivity [MD], axial diffusivity [AD] and radial diffusivity [RD]) of brain white matter (WM) between CADASIL patients and healthy subjects through TBSS. RESULTS: Compared with healthy controls, patients with CADASIL showed extensive decreased FA, MO and increased RD, AD, and MD throughout the entire brain (mainly the WM of the temporal poles, inferior and superior longitudinal fasciculus, inferior fronto-occipital fasciculus, corpus callosum, uncinate fasciculus, internal capsule, external capsule, corona radiata, thalamic radiation, and cingulum). Furthermore, these WM microstructural alterations were significantly correlated with cognitive scores and Scheltens scores. Decreased FA values and MO values were positively correlated with Montreal Cognitive Assessment scores in CADASIL patients. Increased AD, RD, and MD values were significantly negatively correlated with Montreal Cognitive Assessment scores. CONCLUSIONS: Widespread WM abnormalities were clearly shown in CADASIL by using TBSS. Severity of microstructural changes correlates significantly with extension of T2 hyperintensity. Moreover, WM microstructural damage and cognitive impairment were significantly correlated. This study indicated that WM tract damage plays an important role in cognitive impairment in CADASIL.

A randomized, controlled, multicenter clinical trial to evaluate the efficacy and safety of oral sitafloxacin versus moxifloxacin in adult patients with community-acquired pneumonia.

OBJECTIVES: To evaluate the efficacy and safety of oral sitafloxacin versus oral moxifloxacin in the treatment of Chinese adults with community-acquired pneumonia (CAP). PATIENTS AND METHODS: This is a multicenter, randomized, open-label, positive-controlled clinical trial (chinadrugtrials.org.cn identifier: CTR20130046). CAP patients received sitafloxacin tablets 100 mg once daily (qd) or 100 mg twice daily (bid) to compare with moxifloxacin tablets 400 mg qd, for 7-10 days. The primary outcome was non-inferiority of sitafloxacin to moxifloxacin in clinical cure rate at test of cure (TOC) visit in per-protocol set (PPS). RESULTS: A total of 343 patients were randomized (sitafloxacin 100 mg qd, n = 117; sitafloxacin 100 mg bid, n = 116; moxifloxacin, n = 110), 291 patients were included in the PPS (sitafloxacin 100 mg qd, n = 96; sitafloxacin 100 mg bid, n = 94; moxifloxacin, n = 101). The clinical cure rate was 94.8% in the sitafloxacin 100 mg qd group, 96.8% in the sitafloxacin 100 mg bid group and 95.0% in the moxifloxacin group. At the TOC visit, the microbiological success rate was 97.0% (32/33) in the sitafloxacin 100 mg qd group, 97.1% (34/35) in the sitafloxacin 100 mg bid group and 94.9% (37/39) in the moxifloxacin group in the microbiological evaluable set (MES). The incidence of study-drug-related adverse events (AEs) was 23.3% (27/116) in the sitafloxacin 100 mg qd group, 29.8% (34/114) in the sitafloxacin 100 mg bid group and 28.2% (31/110) in the moxifloxacin group (p > .05). The common AEs related to study drug were dizziness, nausea, diarrhea, increased platelet count and alanine transaminase (ALT) elevation. All the AEs resolved completely after discontinuation of study drug. CONCLUSION: Sitafloxacin 100 mg qd or 100 mg bid for 7-10 days is not inferior to moxifloxacin 400 mg qd for 7-10 days in clinical efficacy for adult CAP patients. Sitafloxacin provides a safety profile comparable to moxifloxacin.

Deep learning shows good reliability for automatic segmentation and volume measurement of brain hemorrhage, intraventricular extension, and peripheral edema.

OBJECTIVES: To evaluate for the first time the performance of a deep learning method based on no-new-Net for fully automated segmentation and volumetric measurements of intracerebral hemorrhage (ICH), intraventricular extension of intracerebral hemorrhage (IVH), and perihematomal edema (PHE) in primary ICH on CT. METHODS: Three hundred and eighty primary ICH patients who underwent CT at hospital arrival were divided into a training cohort (n = 300) and a validation cohort (n = 80). An independent cohort with 80 patients was used for testing. Ground truth (segmentation masks) was manually generated by radiologists. Model performance on lesion segmentation and volumetric measurement of ICH, IVH, and PHE were evaluated by comparing the model results with the segmentations performed by radiologists. RESULTS: In the test cohort, the Dice scores of lesion segmentation were 0.92, 0.79, and 0.71 for ICH, IVH, and PHE, respectively. The sensitivities were 0.93 for ICH, 0.88 for IVH, and 0.81 for PHE. The positive predictive values were 0.92, 0.76, and 0.69 for ICH, IVH, and PHE, respectively. Excellent concordance (concordance correlation coefficients [CCCs] ≥ 0.98) of ICH and IVH and good concordance of PHE (CCCs ≥ 0.92) were demonstrated between manually and automatically measured volumes. The model took approximately 15 s to provide automatic segmentation and volume analysis for each patient. CONCLUSION: Our model demonstrates good reliability for automatic segmentation and volume measurement of ICH, IVH, and PHE in primary ICH, which can be useful to reduce the effort and time of doctors to calculate volumes of ICH, IVH, and PHE. KEY POINTS: • Deep learning algorithms can provide automatic and reliable assessment of intracerebral hemorrhage, intraventricular hemorrhage, and perihematomal edema on CT. • Non-contrast CT-based deep learning method can be helpful to provide efficient and accurate measurements of ICH, IVH, and PHE in primary ICH patients, thereby reducing the effort and time of doctors to segment and calculate volumes of ICH, IVH, and PHE in primary ICH patients.

Optimization of Contrast Agent Dosage on Contrast-Enhanced T2 Fluid-Attenuated Inversion Recovery: An In Vitro and In Vivo Study.

OBJECTIVE: This study aimed to ascertain the minimum gadolinium dosage on contrast-enhanced (CE) T2 fluid-attenuated inversion recovery (FLAIR) at appropriate imaging time. METHODS: Different dosages of gadodiamide were imaged with a 3.0-T magnetic resonance scanner for T2-FLAIR and T1WI. Twenty glioma-induced rat models were randomly assigned into 4 groups (1/2, 1/4, 1/6, 1/8 of routine dosage) and imaged for T2-FLAIR and T1WI preinjection and postinjection of gadodiamide. Contrast-enhanced T2-FLAIR was acquired for 8 repetitions postinjection. Enhancement effects were assessed by calculating contrast-noise ratio and contrast ratio using Kruskal-Wallis and Mann-Whitney rank sum test. RESULTS: The in vitro experiment showed that gadodiamide at 1/4 of the T1WI dosage presented the best contrast on CE-T2-FLAIR. For in vivo study, the best enhancement effect on CE-T2-FLAIR was achieved at 1/2 of the routine dosage at 8 to 12 minutes of delayed scanning. Compared with CE-T1WI at routine dosage, CE-T2-FLAIR at 1/2 gadodiamide dosage presented similar enhancement effects with no statistical difference (P = 0.244 and 0.090 for contrast-noise ratio and contrast ratio, respectively). CONCLUSIONS: Contrast-enhanced T2-FLAIR imaging with half of T1WI routine gadodiamide dosage can produce similar enhancement effects to CE-T1WI when characterizing brain gliomas. The cut-down of contrast agent dosage may help reduce gadolinium accumulation in certain tissues.

Genome-wide pathway-based quantitative multiple phenotypes analysis.

For complex diseases, genome-wide pathway association studies have become increasingly promising. Currently, however, pathway-based association analysis mainly focus on a single phenotype, which may insufficient to describe the complex diseases and physiological processes. This work proposes a combination model to evaluate the association between a pathway and multiple phenotypes and to reduce the run time based on asymptotic results. For a single phenotype, we propose a semi-supervised maximum kernel-based U-statistics (mSKU) method to assess the pathway-based association analysis. For multiple phenotypes, we propose the fisher combination function with dependent phenotypes (FC) to transform the p-values between the pathway and each marginal phenotype individually to achieve pathway-based multiple phenotypes analysis. With real data from the Alzheimer Disease Neuroimaging Initiative (ADNI) study and Human Liver Cohort (HLC) study, the FC-mSKU method allows us to specify which pathways are specific to a single phenotype or contribute to common genetic constructions of multiple phenotypes. If we only focus on single-phenotype tests, we may miss some findings for etiology studies. Through extensive simulation studies, the FC-mSKU method demonstrates its advantages compared with its counterparts.

Tumor Immune Microenvironments (TIMEs): Responsive Nanoplatforms for Antitumor Immunotherapy.

Interest in cancer immunotherapy has rapidly risen since it offers many advantages over traditional approaches, such as high efficiency and prevention of metastasis. Efforts have primarily focused on two major strategies for regulating the body's antitumor immune response mechanisms: "enhanced immunotherapy" that aims to amplify the immune activation, and "normalized immunotherapy" that corrects the defective immune mechanism in the tumor immune microenvironments (TIMEs), which returns to the normal immune trajectory. However, due to the complexity and heterogeneity of the TIMEs, and lack of visualization research on the immunotherapy process, cancer immunotherapy has not been widely used in clinical setting. Recently, through the design and modification of nanomaterials, intelligent TIME-responsive nanoplatforms were developed from which encouraging results in many aspects of immunotherapy have been achieved. In this mini review, the status of designed nanomaterials for nanoplatform-based immune regulation of TIMEs has been emphasized, particularly with respect to the aforementioned approaches. It is envisaged that future prospects will focus on a combination of multiple immunotherapies for more efficient cancer inhibition and elimination.

Differentiation of Treatment-Related Effects from Glioma Recurrence Using Machine Learning Classifiers Based Upon Pre-and Post-Contrast T1WI and T2 FLAIR Subtraction Features: A Two-Center Study.

PURPOSE: We propose three support vector machine (SVM) classifiers, using pre-and post-contrast T2 fluid-attenuated inversion recovery (FLAIR) subtraction and/or pre-and post-contrast T1WI subtraction, to differentiate treatment-related effects (TRE) from glioma recurrence. MATERIALS AND METHODS: Fifty-six postoperative high-grade glioma patients with suspicious progression after radiotherapy and chemotherapy from two centers were studied. Pre-and post-contrast T1WI and T2 FLAIR were collected. Each pre-contrast image was voxel-wise subtracted from the co-registered post-contrast image. Dataset was randomly split into training, and testing on a 7:3 ratio, accordingly subjected to a five fold cross validation. Best feature subsets were selected by Pearson correlation coefficient and recursive feature elimination, whereupon a radiomics classifier was built with SVM. The discriminating performance was assessed with the area under receiver-operating characteristic curve (AUC), accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). RESULTS: In all, 186 features were extracted on each subtraction map. Top nine T1WI subtraction features, top thirteen T2 FLAIR subtraction features and top thirteen combination features were selected to build optimal SVM classifiers accordingly. The accuracies/AUCs/sensitivity/specificity/PPV/NPV of SVM based on sole T1WI subtraction were 80.00%/80.00% (CI: 0.5370-1.0000)/100%/70.00%/62.50%/100%. Those results of SVM based on sole T2 FLAIR subtraction were 86.67%/84.00% (CI: 0.5962-1.0000)/100%/80%/71.43%/100%. Those results of SVM based on both T1WI subtraction and T2 FLAIR subtraction were 93.33%/94.00% (CI: 0.7778-1.0000)/100%/90%/83.33%/100%, respectively. CONCLUSION: Pre- and post-contrast T2 FLAIR subtraction provided added value for diagnosis between recurrence and TRE. SVM based on a combination of T1WI and T2 FLAIR subtraction maps was superior to the sole use of T1WI or T2 FLAIR for differentiating TRE from recurrence. The SVM classifier based on combination of pre-and post-contrast subtraction T2 FLAIR and T1WI imaging allowed for the accurate differential diagnosis of TRE from recurrence, which is of paramount importance for treatment management of postoperative glioma patients after radiation therapy.

Iron Sucrose as MRI Contrast Agent in Ischemic Stroke Model.

BACKGROUND: Despite the growing concern about the safety of gadolinium-based contrast agents (GBCAs), they are still the most commonly used. Ferumoxytol, as an off-label alternative MRI contrast agent, cannot be administered by a rapid bolus for dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI). PURPOSE: To assess the feasibility of iron sucrose (IS) as a contrast agent for MR angiography (MRA) and DSC-PWI. STUDY TYPE: Prospective animal model. ANIMAL MODEL: Thirty-six normal rats (16 for MRA, 20 for biocompability tests) and 36 occlusion of the middle cerebral artery (MCAO) model rats. FIELD STRENGTH/SEQUENCE: 3.0T; head and neck angiography, using a fast spoiled gradient-recalled-echo (FSPGR) sequence and DSC-MRI using echo planar imaging(EPI) sequence. ASSESSMENT: MRA was performed on normal rats to examine the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of different doses of IS. DSC-PWI was performed on MCAO rats at 0, 24, 48, and 72 hours postreperfusion to investigate the lesion detectability of IS. Arterial spin labeling (ASL) and DSC-PWI enhanced by GBCAs were conducted on MCAO rats as controls. STATISTICAL TESTS: Kruskal-Wallis test was used to compare qualitative assessment. One-way analysis of variance (ANOVA) was used to compare the parametric data. Pearson's r values were evaluated between relative cerebral blood flow(rCBF)-ASL, rCBF-DSCIS , and rCBF obtained from DSC-PWI enhanced by GBCA. RESULTS: The mean SNR and CNR of the common carotid artery at doses of 10 mg Fe/kg of IS were comparable with the standard dose of GBCAs (SNR: 68.04 ± 12.55 vs. 67.72 ± 14.66; CNR: 23.78 ± 7.21vs. 21.63 ± 6.83). In MCAO rat models, rCBF and relative cerebral blood volume (rCBV) of ipsilateral striatum declined (0.72 ± 0.14, 0.86 ± 0.11) with prolonged relative mean transit time (rMTT) and relative time-to-peak (rTTP) (1.27 ± 0.24, 1.07 ± 0.03) following occlusion. Hyperperfusion was observed in all rats at 48 and 72 hours postreperfusion, in 4/6 rats at 24 hours postreperfusion for IS-mediated DSC-PWI. DATA CONCLUSION: IS may be an effective contrast agent for both MRA and DSC-PWI in ischemic stroke models. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY STAGE: 1 J. Magn. Reson. Imaging 2020;52:836-849.