Amide Proton Transfer-Weighted Magnetic Resonance Imaging for Application in Renal Fibrosis: A Radiological-Pathological-Based Analysis.

INTRODUCTION: Renal fibrosis (RF), being the most important pathological change in the progression of CKD, is currently assessed by the evaluation of a biopsy. This present study aimed to apply a novel functional MRI (fMRI) protocol named amide proton transfer (APT) weighting to evaluate RF noninvasively. METHODS: Male Sprague-Dawley (SD) rats were initially subjected to bilateral kidney ischemia/reperfusion injury (IRI), unilateral ureteral obstruction, and sham operation, respectively. All rats underwent APT mapping on the 7th and 14th days after operation. Besides, 26 patients underwent renal biopsy at the Nephrology Department of Shanghai Tongji Hospital between July 2022 and May 2023. Patients underwent APT and apparent diffusion coefficient (ADC) mappings within 1 week before biopsy. MRI results of both patients and rats were calculated by comparing with gold standard histology for fibrosis assessment. RESULTS: In animal models, the cortical APT (cAPT) and medullary APT (mAPT) values were positively correlated with the degree of RF. Compared to the sham group, IRI group showed significantly increased cAPT and mAPT values on the 7th and 14th days after surgery, but no group differences were found in ADC values. Similar results were found in human patients. Cortical/medullary APT values were significantly increased in patients with moderate-to-severe fibrosis than in patients with mild fibrosis. ROC curve analysis indicated that APT value displayed a better diagnostic value for RF. Furthermore, combination of cADC and cAPT improved fibrosis detection by imaging variables alone (p < 0.1). CONCLUSION: APT values had better diagnostic capability at early stage of RF compared to ADC values, and the addition of APT imaging to conventional ADC will significantly improve the diagnostic performance for predicting kidney fibrosis.

The Value of Amide Proton Transfer MRI in the Diagnosis of Malignant and Benign Urinary Bladder Lesions: Comparison With Diffusion-Weighted Imaging.

BACKGROUND: Conventional magnetic resonance imaging (MRI) has certain limitations in distinguishing between malignant and benign urinary bladder (UB) lesions. Amide proton transfer (APT) imaging may provide more diagnostic information than diffusion-weighted imaging (DWI) to distinguish between malignant and benign UB. PURPOSE: To investigate the potential of APT imaging in the diagnosis of malignant and benign UB lesions and to compare its diagnostic efficacy with that of conventional DWI. STUDY TYPE: Prospective. SUBJECTS: Eighty patients with UB lesions. FIELD STRENGTH/SEQUENCE: A 3.0 T/turbo spin echo (TSE) T1-weighted and T2-weighted imaging, single-shot echo planar DWI, and three-dimensional TSE APT imaging. ASSESSMENT: Patients underwent radical cystectomy or transurethral resection of the bladder lesions within 2 weeks after CT urography and MRI examination. APT signal intensity in UB lesions was quantified by the asymmetric magnetization transfer ratio (MTRasym). MTRasym and apparent diffusion coefficient (ADC) values were measured and compared between malignant and benign UB lesions. STATISTICAL TESTS: Kolmogorov-Smirnov test, Student's t test or Mann-Whitney U test, Spearman rank correlation coefficient, area under the receiver operating characteristic (ROC) curve (AUC), Delong test, and intraclass correlation coefficient (ICC). The significance threshold was set at P < 0.05. RESULTS: Thirty-two patients had pathologically confirmed benign UB lesions, including 2 bladder leiomyomas, 1 submucosal amyloidosis, 1 inflammatory myofibroblastic tumor, and 28 inflammatory lesions, and 48 patients had pathologically confirmed urothelial carcinoma. Urothelial carcinomas showed significantly higher MTRasym values (1.53% [0.74%] vs. 0.85% [0.23%]) and significantly lower ADC values (1.24 ± 0.34 × 10-3 mm2/s vs. 1.43 ± 0.22 × 10-3 mm2/s) than benign UB lesions. The MTRasym value (AUC = 0.928) was significantly better in differentiating urothelial carcinoma from benign UB lesions than the ADC value (AUC = 0.722). DATA CONCLUSION: APT imaging may have value in discriminating malignant from benign UB lesions and has better diagnostic performance than DWI. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

Early tracheostomy is associated with better prognosis in patients with brainstem hemorrhage.

Brainstem hemorrhage is presumed to be invariably associated with a poor prognosis in people with spontaneous hypertensive cerebral hemorrhage. The optimal timing of tracheostomy placement in brainstem hemorrhage patients, who generally require endotracheal intubation for airway protection, remains uncertain. Our research aim was to analyze the impact of early tracheostomy versus late tracheostomy on brainstem hemorrhage patients related outcomes and prognostic factors at 30 days. We identified early tracheostomy and how it could benefit the patients with brainstem hemorrhage and ameliorate the predictors of functional recovery at 30 days. Data on 136 patients with brainstem hemorrhage and Glasgow Coma Scale score ≤ 8, were retrospectively collected from 2012 to 2019. Patients were divided into the early tracheostomy group and the late tracheostomy group. Patients in the early tracheostomy group had a significantly lower neurosurgical intensive care unit stay (both overall and survival) compared with the late tracheostomy group (15.6 days vs. 19.0 days, P = 0.041, overall and 14.5 vs. 19.5 days, P = 0.023, survival). Also, the good outcomes (modified Rankin Score ≤ 3) were higher in the early tracheostomy group (P = 0.036). Multivariate analysis demonstrated that less hemorrhagic volume, high Glasgow Coma Scale score on admission, young age, and early tracheostomy were significantly associated with a better 30-day functional outcome. In conclusion, an early tracheostomy in patients with brainstem hemorrhage can reduce neurosurgical intensive care unit stay, and in addition to improvements in prognosis at 30 days.

Comparative analysis of amide proton transfer and diffusion-weighted imaging for assessing Ki-67, p53 and PD-L1 expression in bladder cancer.

RATIONALE AND OBJECTIVES: To evaluate amide proton transfer (APT) imaging for assessing Ki-67, p53 and PD-L1 status in bladder cancer (BC) and compare its diagnostic efficacy with that of diffusion-weighted imaging (DWI). MATERIALS AND METHODS: Consecutive patients suspected of BC were recruited for preoperative multiparametric MRI. APT signal was quantified by asymmetric magnetization transfer ratio (MTRasym). MTRasym and apparent diffusion coefficient (ADC) were measured by two radiologists, with interobserver agreement assessed. Spearman's correlation analyzed MTRasym values and molecular markers. The Whitney U test evaluated MTRasym and ADC variation based on molecular marker status. Optimal cutoff points were determined using area under the curve (AUC) analysis. RESULTS: 88 patients (72 ± 10 years; 77 men) with BC were studied. MTRasym values were significantly correlated with Ki-67, p53 and PD-L1 levels (P < 0.05). Higher MTRasym values were found in high Ki-67 expression BCs (1.89% [0.73%] vs. 1.23% ± 0.26%; P < 0.001), high p53 expression BCs (1.63% [0.56%] vs. 1.24% [0.56%]; P < 0.001) and positive PD-L1 expression BCs (2.02% [0.81%] vs. 1.48% [0.38%]; P < 0.001). Lower ADCs were found in high Ki-67 expression BCs (1.06 ×10-3 mm2/s [0.32 ×10-3 mm2/s] vs. 1.38 ×10-3 mm2/s [0.39 ×10-3 mm2/s]; P < 0.001). For p53 status, an MTRasym threshold of 1.27% had 95% sensitivity, 60% specificity, and AUC of 0.781. For PD-L1 status, a 1.90% threshold had 88% sensitivity, 92% specificity, and AUC of 0.859. CONCLUSION: APT may significantly enhance the preoperative assessment of BC aggressiveness and inform targeted immunotherapy decisions, with performance superior to DWI.

Evaluation of amide proton transfer imaging for bladder cancer histopathologic features: A comparative study with diffusion- weighted imaging.

PURPOSE: To assess the ability of amide proton transfer (APT) imaging, in comparison with diffusion-weighted imaging (DWI), to differentiate low-grade from high-grade bladder tumors and predict the aggressiveness of bladder cancer (BCa). METHODS: Forty-eight patients diagnosed with BCa confirmed by histopathological findings who underwent magnetic resonance (MR) imaging, including APT imaging and DWI (b = 0, 1000 sec/mm2), were enrolled in this study. The asymmetric magnetization transfer ratio (MTRasym) was defined as the magnetization transfer asymmetry at 3.5 ppm. MTRasym and apparent diffusion coefficients (ADCs) were compared between the low- and high-grade groups and between non-muscle-invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC) in terms of the areas under the receiver operating characteristic curves (AUCs). RESULTS: The MTRasym values were significantly higher in patients with high-grade bladder tumors than in those with low-grade tumors (1.61 % [0.76 %], 1.12 ± 0.3 %; P = 0.000) and in MIBC than in NMIBC (2.53 ± 0.67 %, 1.38 % [0.35 %]; P = 0.000). The AUCs of MTRasym were significantly larger than those of ADC for differentiating MIBC from NMIBC (0.973, 0.771; P = 0.016). Adding APT imaging to DWI significantly improved the diagnostic accuracy for differentiating MIBC from NMIBC versus DWI alone (0.985, 0.876; P = 0.013). CONCLUSIONS: APT imaging can predict tumor grade and aggressiveness in BCa. The diagnostic performance of APT imaging in predicting tumor aggressiveness was better than that of DWI, and adding APT imaging to DWI significantly improved the diagnostic accuracy of predicting tumor aggressiveness versus DWI alone.

[Variation characteristics of farmland soil pH in the past 30 years of Enshi Autonomous Prefecture, Hubei, China]. / 恩施州耕地土壤pH近30年变化特征.

In order to explore temporal-spatial variability of farmland soil pH at Enshi Antonomous Prefecture, Hubei, China, soil pH during the past three decades was analyzed, using the datasets of the Second National Soil Survey (1980-1983) and the Cultivated Land Quality Evaluation (2010-2013). The natural and human factors inducing the change of soil pH were evaluated to provide theoretical guidance for further soil acidification management. Results showed that acidic soil (i.e., pH＜6.5) and neutral and alkaline soil (i.e., pH 6.5-8.5) were accounted for 98.4% and 1.6% in the farmland during the period of 2010-2013, respectively. The ratio increased 61.4% for the acidic soil but decreased 61.2% for the neutral and alkaline soil as compared with the period of 1980-1983. In addition, there was no alkaline soil (pH>8.5) in the region in 2010-2013. According to the dataset of the Second National Soil Survey (1980-1983), acidic soil was mainly distributed at Laifeng, Lichuan, Xuanen and Xianfeng counties, with the area ratio of 74.4%, 63.5%, 61.3% and 60.7%, respectively. For the period of 2010-2013, the ratio of acidic soil enhanced widely which was above 96% for each county. At Enshi Autonomous Prefecture, farmland soil showed an obvious acidification trend during the past three decades, with spatial variation of higher in the eastern part and lower in the western part of the region. Furthermore, soil pH decline occurred among different land use types in different areas. Overall, farmland soil pH declined 0.90 on average, with 1.14 decrease for upland and 0.87 for paddy soil, respectively. Clearly, upland soil acidification was severe than paddy soil. Factors related to soil acidification in the Enshi Autonomous Prefecture were mainly human factors such as unreasonable fertilizer combination, fertilizer ratio change, and more base cations taking away by high crop yield.

[Damaging nucleus centromedianus thalami for treatment of cancer pain in experimental and clinical aspects].

BACKGROUND & OBJECTIVE: There is no perfect method to control cancer pain. It is reported that nucleus centromedianus thalami plays a crucial role in the analgesia of central nerve system. The authors conducted this study, based on rat experiments, together with the clinical treatment of more than 90 cases involving various cancer pains, to explore the pain-relieving effects after damaging nucleus centromedianus thalami. METHODS: Ten SD rats, whose nucleus centromedianus thalami were damaged by electrolysis, were chosen, and then measured the pain degree by applying electricity to stimulate the tails of the rats. Meanwhile, another 10 rats, whose nucleus centromedianus thalami were not damaged, were chosen as the control group, among whom the same operation procedure as the above mentioned was carried out. The range of pain scale of the rats was measured by the alteration of the electric intensity. A total of 90 cases of intractable cancer pain were treated, including 36 cases of lung cancer, 21 cases of nasopharyngeal carcinoma, 10 cases of intestinal cancer, 8 cases of cancer of pancreas, 8 cases of osteocarcinoma, 4 cases of carcinoma of kidney, 3 cases of hepatocarcinoma. The brain stereotactic technique was used to damage the nucleus centromedianus thalami with radiofrequency coagulation lesions. The 10-grade method recommended by WHO was used to rank pain degree. RESULTS: Pain scale of rats in the first group rose from 0.152+/-0.034 mA prior to the damage to 0.326+/-0.05 afterwards, with a significant difference (P< 0.001), while the pain scale of the control group dropped from 0.142+/-0.027 mA prior to the operation to 0.138+/-0.035 mA afterwards, with no remarkable difference (P > 0.05). To patients with cancer pain, the average pain grade in this study went above 7 scores, but dropped to 0-3 scores after operation, according to the 10 grade method by WHO. A life-long tracing observation indicted that cancer pain in 24 cases relapsed to varying degrees but below 5 scores, the rest of the patients were analgesic persistently, 3 cases among whom lasted for as long as 2 years. The incidence cases of operational complications were 15 of somnolence, 10 of urinary incontinence, 8 of divagation, and 3 of unilateral oculomotor paralysis. These complications released after symptomatic treatments. CONCLUSION: Nucleus centromedianus thalami damage is an effective way to relieve cancer pain, as well as the complications should be paid attention.