SiMix: A domain generalization method for cross-site brain MRI harmonization via site mixing.

Brain magnetic resonance imaging (MRI) is widely used in clinical practice for disease diagnosis. However, MRI scans acquired at different sites can have different appearances due to the difference in the hardware, pulse sequence, and imaging parameter. It is important to reduce or eliminate such cross-site variations with brain MRI harmonization so that downstream image processing and analysis is performed consistently. Previous works on the harmonization problem require the data acquired from the sites of interest for model training. But in real-world scenarios there can be test data from a new site of interest after the model is trained, and training data from the new site is unavailable when the model is trained. In this case, previous methods cannot optimally handle the test data from the new unseen site. To address the problem, in this work we explore domain generalization for brain MRI harmonization and propose Site Mix (SiMix). We assume that images of travelling subjects are acquired at a few existing sites for model training. To allow the training data to better represent the test data from unseen sites, we first propose to mix the training images belonging to different sites stochastically, which substantially increases the diversity of the training data while preserving the authenticity of the mixed training images. Second, at test time, when a test image from an unseen site is given, we propose a multiview strategy that perturbs the test image with preserved authenticity and ensembles the harmonization results of the perturbed images for improved harmonization quality. To validate SiMix, we performed experiments on the publicly available SRPBS dataset and MUSHAC dataset that comprised brain MRI acquired at nine and two different sites, respectively. The results indicate that SiMix improves brain MRI harmonization for unseen sites, and it is also beneficial to the harmonization of existing sites.

A deep-learning system to help make the surgical planning of coil embolization for unruptured intracranial aneurysms.

BACKGROUND: Coil embolization is a common method for treating unruptured intracranial aneurysms (UIAs). To effectively perform coil embolization for UIAs, clinicians must undergo extensive training with the assistance of senior physicians over an extended period. This study aimed to establish a deep-learning system for measuring the morphological features of UIAs and help the surgical planning of coil embolization for UIAs. METHODS: Preoperative computational tomography angiography (CTA) data and surgical data from UIA patients receiving coil embolization in our medical institution were retrospectively reviewed. A convolutional neural network (CNN) model was trained on the preoperative CTA data, and the morphological features of UIAs were measured automatically using this CNN model. The intraclass correlation coefficient (ICC) was utilized to examine the similarity between the morphologies measured by the CNN model and those determined by experienced clinicians. A deep neural network model to determine the diameter of first coil was further established based on the CNN model within the derivation set (75% of all patients) using neural factorization machines (NFM) model and was validated using a validation set (25% of all patients). The general match ratio (the difference was within ± 1 mm) between the predicted diameter of first coil by model and that used in practical scenario was calculated. RESULTS: One-hundred fifty-three UIA patients were enrolled in this study. The CNN model could diagnose UIAs with an accuracy of 0.97. The performance of this CNN model in measuring the morphological features of UIAs (i.e., size, height, neck diameter, dome diameter, and volume) was comparable to the accuracy of senior clinicians (all ICC > 0.85). The diameter of first coil predicted by the model established based on CNN model and the diameter of first coil used actually exhibited a high general match ratio (0.90) within the derivation set. Moreover, the model performed well in recommending the diameter of first coil within the validation set (general match ratio as 0.91). CONCLUSION: This study presents a deep-learning system which can help to improve surgical planning of coil embolization for UIAs.

Resting-state functional connectivity of salience network in schizophrenia and depression.

To explore the salience network (SN) functional alterations in schizophrenia and depression, resting-state functional magnetic resonance imaging (rs-fMRI) data from 29 patients with schizophrenia (SCH), 28 patients with depression (DEP) and 30 healthy controls (HC) were obtained. The SN was derived from data-driven group independent component analysis (gICA). ANCOVA and post hoc tests were performed to discover the FC differences of SN between groups. The ANCOVA demonstrated a significant group effect in FC with right inferior and middle temporal gyrus (ITG and MTG), left caudate, and right precentral gyrus. Post-hoc analyses revealed an opposite altered FC pattern between SN and right ITG and MTG for both patient groups. The DEP group showed a reduced FC between SN and right ITG and MTG compared with HC whereas the SCH group showed an increased FC. In addition, the SCH group showed decreased FC between SN and left caudate, and enhanced FC between SN and right precentral gyrus compared to the other two groups. Our findings suggest distinct FC of SN in schizophrenia and depression, supporting that the resting-state FC pattern of SN may be a transdiagnostic difference between depression and schizophrenia and may play a critical role in the pathogenesis of these two disorders.

Serum IL-1, Pyroptosis and Intracranial Aneurysm Wall Enhancement: Analysis Integrating Radiology, Serum Cytokines and Histology.

BACKGROUND AND PURPOSE: Aneurysm wall enhancement (AWE) is correlated with the rupture and growth risk of unruptured intracranial aneurysms (UIAs). Pyroptosis is a proinflammation mode of lytic cell death, mediated by pyroptosis-related proteins, i.e., gasdermin D and interleukin 1 ß (IL-1ß). Integrating serum cytokines and histology, this study aimed to investigate the correlation between AWE and pyroptosis in UIAs. METHODS: UIA patients receiving microsurgical clipping were prospectively enrolled from January 2017 and June 2020. UIA samples were collected, as well as the corresponding blood samples. In this study, high-resolution magnetic resonance was employed to identify the AWE. The serum 46-cytokines examination and the histological analysis were conducted to determine pyroptosis, CD68 and MMP2. The IL-1 ra/beta ratio was determined by complying with the serum IL-1ß and IL-1.ra. A comparison was drawn in the differences between UIAs with and without AWE. Lastly, the correlation between inflammation in UIA samples and serums was investigated. RESULTS: This study included 34 UIA patients. The serum proinflammatory cytokines [IL-1ß (P < 0.001) and TNF-α (P < 0.001)] were up-regulated, and serum anti-inflammatory cytokine (IL-1.ra, P = 0.042) were down-regulated in patients with AWE UIAs. The patients with AWE UIAs achieved a higher IL-1.ra/beta ratio (P < 0.001). The multivariate logistic analysis demonstrated IL-1ß [odds ratio (OR), 1.15; 95% confidence interval (CI), 1.02-1.30; P = 0.028] and IL-1.ra (OR, 0.998; 95% CI, 0.997-1.000; P = 0.017) as the risk factors correlated with the AWE. IL-1.ra/beta ratio achieved the highest predictive accuracy [area under the curve (AUC), 0.96] for AWE, followed by IL-1.ra (AUC, 0.90), IL-1ß (AUC, 0.88) and TNF-α (AUC, 0.85). As compared with the UIAs without AWE, the AWE UIAs were manifested as a severer wall remodeling, with higher relative levels of pyroptosis-related proteins, CD68 and MMP2. The serum IL-1ß, IL-1.ra and IL-1.ra/beta ratio had a positive correlation with the relative levels of pyroptosis-related proteins, CD68 and MMP2 in UIA tissues. CONCLUSION: The serum IL-1ß and IL-1.ra were correlated with the AWE. More pyroptosis-related proteins were identified in UIAs with AWE. The serum IL-1ß and IL-1.ra were correlated with the pyroptosis-related proteins in aneurysm tissues.

Operating status of public toilets in the Hutong neighborhoods of Beijing: An empirical study.

The provision of sanitation services for fast-growing urban populations is one of the world's urgent challenges. Hutong neighborhoods in Beijing, capital of China, cannot be rebuilt due to the protection of historical heritage, while residents still need to keep the habit of defecating in public toilets. One hundred public toilets with non-sewered sanitation in the Hutong neighborhoods of Beijing were visited to investigate the actual operating status in response to the "toilet revolution" campaign. The fault tree approach was used to identify the barriers toward a decent and environment-friendly public toilet and evaluate potential risks from the malfunction of various components. Four subsystems are defined and elaborated to calculate the fault possibility. These subsystems are environment- and user-friendly, regarded as ancillary facilities, and used for fecal sludge (FS) management. Statistical analysis of targeted cases indicated that fault probabilities of environmental considerations, user-friendly considerations, ancillary facilities, FS management are calculated as 0.79, 0.96, 0.96, and 0, respectively. The subsystems were weighted using a Delphi method concept. Results showed that the well operation ratio of Beijing Hutong public toilets is only 32%, and the sanitation service value chain can be further optimized. This study also provides references for other countries, which are dedicated to promoting urban sanitation and public health.

Improved NLMS-based adaptive denoising method for ECG signals.

BACKGROUND: Traditional least mean square algorithm (LMS) tends to converge faster and thus the larger the steady-state error of the algorithm. OBJECTIVE: In order to solve this issue, an improved adaptive normalized least mean square (NLMS) ECG signal denoising algorithm is proposed through utilizing the NLMS and the least mean square algorithm with added momentum term (MLMS). METHODS: The algorithm firstly performs LMS adaptive filtering on the original ECG signal. Then, the algorithm uses the relative error of the prior error signal and the posterior error signal before and after filtering to adaptively determine the iteration step factor. Finally, the expected error is set to determine whether the denoising meets the expected requirements. This method is applied to the MIT-BIH ECG database established by the Massachusetts Institute of Technology. RESULTS: Experimental results have shown that the proposed algorithm can achieve good denoising for the target signal, and the average signal to noise ratio (SNR) of the proposed method is 17.6016, the RMSE is only 0.0334, and the average smoothness index R is only 0.0325. CONCLUSION: The proposed algorithm effectively removes the original ECG signal noise, and improves the smoothness of the signal the denoising efficiency.

[Prognostic significance of serum lactic acid in evaluation of acute paraquat poisoning patients].

OBJECTIVE: To discuss the role of serum lactic acid (Lac) level in evaluation of prognosis of acute paraquat poisoning (APP) patients. METHODS: Clinical data from 168 APP patients were retrospectively analyzed. The serum Lac level and the plasma paraquat concentrations at admission were collected, and the severity index of paraquat poisoning (SIPP) were calculated. The patients were divided into <10, 10-50, ≥50 h×mg×L(-1) groups on the basis of SIPP. The correlation between Lac and SIPP was analyzed, as well as the role in evaluating prognosis. RESULTS: The higher the SIPP level, the higher the Lac level [2.00 (1.50, 2.83) mmol/L, 3.10 (1.73, 5.15) mmol/L, 8.95 (5.90, 13.10) mmol/L, all P<0.05]; Lac was correlated positively with SIPP (r=0.569, P<0.05). The higher the SIPP, the higher the mortality of patients [17.4% (15/86), 61.5% (24/39), 97.7% (42/43), all P<0.05]. The survival days of SIPP≥50 h×mg×L(-1) group was shorter than that in SIPP<10 h×mg×L(-1) group and 10-50 h×mg×L(-1) group [2.0 (1.0, 3.0) days vs. 9.0 (4.0, 11.0) days and 5.0 (3.0, 10.0) days, both P<0.05]. A negative correlation was found between Lac, SIPP and survival days in non-survivors (r1=-0.778, r2=-0.621, both P<0.05). Logistic regression analyses showed either Lac or SIPP was of prognostic significance [odds ratio (OR) of Lac: 1.758, 95% confidence interval (95%CI) 1.278-2.417;OR of SIPP: 1.063,95%CI 1.025-1.103, both P=0.001]. The area under the receiver operating characteristic curve (ROC curve) of Lac, SIPP and prognosis were 0.885 and 0.897 respectively (both P<0.05), Lac≥3.35 mmol/L was the best cut-off value, the sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio and accuracy for predicting the death were 74.07%, 90.80%, 88.24%, 79.00%, 8.056, 0.286 and 82.74% respectively; the evaluation value was closed to SIPP≥13.83 h×mg×L(-1) (77.78%, 91.95%, 90.00%, 81.63%, 9.677, 0.242 and 85.12%, respectively). CONCLUSIONS: The change in serum Lac level has evaluation value of the severity and prognosis for APP patients, and Lac≥3.35 mmol/L can be made as a simple and easy indicator for prognosis of APP patients.

Altered spontaneous activity in antisocial personality disorder revealed by regional homogeneity.

There is increasing evidence that antisocial personality disorder (ASPD) stems from brain abnormalities. However, there are only a few studies investigating brain structure in ASPD. The aim of this study was to find regional coherence abnormalities in resting-state functional MRI of ASPD. Thirty-two ASPD individuals and 34 controls underwent a resting-state functional MRI scan. The regional homogeneity (ReHo) approach was used to examine whether ASPD was related to alterations in resting-state neural activity. Support vector machine discriminant analysis was used to evaluate the sensitivity/specificity characteristics of the ReHo index in discriminating between the ASPD individuals and controls. The results showed that, compared with controls, ASPD individuals show lower ReHo in the right cerebellum posterior lobe (Crus1) and the right middle frontal gyrus, as well as higher ReHo in the right middle occipital gyrus (BA 19), left inferior temporal gyrus (BA 37), and right inferior occipital gyrus (cuneus, BA 18). All alternation regions reported a predictive accuracy above 70%. To our knowledge, this study was the first to study the change in regional activity coherence in the resting brain of ASPD individuals. These results not only elucidated the pathological mechanism of ASPD from a resting-state functional viewpoint but also showed that these alterations in ReHo may serve as potential markers for the detection of ASPD.

[The clinical application of plantar medial perforator artery based reverse island medial dorsal pedal neurocutaneous vascular flaps].

OBJECTIVE: To explore the clinical effect of plantar medial perforator artery based reverse island medial dorsal pedal neurocutaneous vascular flaps. METHODS: 12 cases with soft tissue defects of forefeet were treated by plantar medial perforator artery based reverse island medial dorsal pedal neurocutaneous vascular flaps. The flap size ranged from 3.0 cm x 3.5 cm to 5.5 cm x 8.5 cm. RESULT: All flaps survived completely. The patients were followed up for 6 - 24 months. The texture and flexibility of the flaps were normal with no ulcer. The sensation improved with the two-point discrimination of 7 - 10 mm. The cosmetic and functional results were satisfactory. The wounds at donor site healed primarily. CONCLUSIONS: The flaps have expanded size for large defects with good flexibility, thickness and texture. It is easily performed with less morbidity to main artery.