Multitask deep learning for prediction of microvascular invasion and recurrence-free survival in hepatocellular carcinoma based on MRI images.

BACKGROUND AND AIMS: Accurate preoperative prediction of microvascular invasion (MVI) and recurrence-free survival (RFS) is vital for personalised hepatocellular carcinoma (HCC) management. We developed a multitask deep learning model to predict MVI and RFS using preoperative MRI scans. METHODS: Utilising a retrospective dataset of 725 HCC patients from seven institutions, we developed and validated a multitask deep learning model focused on predicting MVI and RFS. The model employs a transformer architecture to extract critical features from preoperative MRI scans. It was trained on a set of 234 patients and internally validated on a set of 58 patients. External validation was performed using three independent sets (n = 212, 111, 110). RESULTS: The multitask deep learning model yielded high MVI prediction accuracy, with AUC values of 0.918 for the training set and 0.800 for the internal test set. In external test sets, AUC values were 0.837, 0.815 and 0.800. Radiologists' sensitivity and inter-rater agreement for MVI prediction improved significantly when integrated with the model. For RFS, the model achieved C-index values of 0.763 in the training set and ranged between 0.628 and 0.728 in external test sets. Notably, PA-TACE improved RFS only in patients predicted to have high MVI risk and low survival scores (p < .001). CONCLUSIONS: Our deep learning model allows accurate MVI and survival prediction in HCC patients. Prospective studies are warranted to assess the clinical utility of this model in guiding personalised treatment in conjunction with clinical criteria.

Comparative Decellularization and Recellularization of Normal Versus Streptozotocin-Induced Diabetes Mellitus Rat Pancreas.

Decellularized (DC) organs/tissues offer a promising scaffold for regenerative bioengineering. However, it is not clear whether the diabetic mellitus (DM) pancreas can be used in decellularized and recellularized bioengineering. For assessment of these questions, murine pancreatic scaffolds of normal, type 1DM (T1DM) and type 2 DM (T2DM) pancreas were generated using a perfusion decellularization technique and assessed by histology, scanning electron microscopy, immunohistochemistry, and enzyme-linked immunosorbent assay (ELISA). The capacity of DC pancreatic scaffolds to support attachment and proliferation of human umbilical vein endothelial cells (HUVECs) and MIN-6 ß cells was also assessed. Our results showed that DC pancreatic scaffolds were successfully produced from T1DM and T2DM pancreas and maintained their extracellular matrix (ECM) composition, 3D ultrastructure, and various cytokines. All of the pancreatic scaffolds were sufficiently cytocompatible and were able to support proliferation and adhesion of HUVECs and MIN-6 ß cells. The preliminary results support the biological utility of diabetes mellitus pancreatic scaffolds and pave the way for further investigations to assess the potential ability of using diabetes mellitus pancreas as scaffolds for recellularization and eventual medical applications.

Elderly population have a decreased aneurysmal subarachnoid hemorrhage incidence rate than Middle aged population: a descriptive analysis of 8,144 cases in mainland China.

PURPOSE: Rupture of an intracranial aneurysm is a life-threatening acute cerebrovascular event. The purpose of this study was to investigate whether aneurysmal subarachnoid haemorrhage (SAH) incidence rate is higher or lower in elderly population than in middle aged population. MATERIALS AND METHODS: Aneurysmal SAH cases were collected retrospectively from the archives of 21 hospitals in Mainland China. All the cases were collected from September 2016 and backward consecutively for a period of time up to 8 years. SAH was initially diagnosed by brain computed tomography (CT). CT angiography (CTA) or digital subtraction angiography (DSA) was followed and SAH was confirmed to be due to cerebral aneurysm rupture. For cases when multiple bleeding occurred, the age of the first SAH was used in this study. The total incidence from all hospitals at each age group were summed together for females and males respectively; then adjusted by the total population number at each age group for females and males which was from the 2010 population census of the People's Republic of China. RESULTS: In total there were 8,144 cases of intracranial aneurysmal SAH, with 4,861 females and 3,283 males. For females the relative aneurysmal SAH incidence rate started to decrease after around 65 years old, while for males the relative aneurysmal SAH incidence rate started to decrease after around 53 years old. CONCLUSION: Our data tentatively suggest elderly patients may be at a reduced risk of rupture compared with patients who are younger while have similar other risk factors.

Whole-brain 320-detector row dynamic volume CT perfusion detected crossed cerebellar diaschisis after spontaneous intracerebral hemorrhage.

INTRODUCTION: The purpose of this study was to evaluate the value of 320-detector row CT used to detect crossed cerebellar diaschisis (CCD) in patients with unilateral supratentorial spontaneous intracerebral hemorrhage (SICH). METHODS: We investigated 62 of 156 patients with unilateral supratentorial SICH using 320-detector row CT scanning. Regional cerebral blood flow (rCBF), cerebral blood volume (rCBV), mean transit time (rMTT), and time to peak (rTTP) levels were measured in different regions of interest (ROIs) that were manually outlined on computed tomography perfusion (CTP) for the cerebrum, including normal-appearing brain tissue that surrounded the perilesional low-density area (NA) and the perihematomal low-density area (PA) in all patients and the cerebellum (ipsilateral and contralateral) in CCD-positive patients. RESULTS: Of 62 cases, a total of 14 met the criteria for CCD due to cerebellar perfusion asymmetry on CTP maps. In the quantitative analysis, significant differences were found in the perfusion parameters between the contralateral and ipsilateral cerebellum in CCD-positive cases. No significant differences were found between the CCD-positive group and the CCD-negative group according to the hematoma volume, NIHSS scores, and cerebral perfusion abnormality (each P > 0.05). The correlation analysis of the degree of NA, PA perfusion abnormality, and the degree of CCD severity showed negative and significant linear correlations (R, -0.66∼-0.56; P < 0.05). CONCLUSION: 320-detector row CT is a robust and practicable method for the comprehensive primary imaging work-up of CCD in unilateral supratentorial SICH patients.

Discriminating atypical parotid carcinoma and pleomorphic adenoma utilizing extracellular volume fraction and arterial enhancement fraction derived from contrast-enhanced CT imaging: A multicenter study.

OBJECTIVES: To investigate the added value of extracellular volume fraction (ECV) and arterial enhancement fraction (AEF) derived from enhanced CT to conventional image and clinical features for differentiating between pleomorphic adenoma (PA) and atypical parotid adenocarcinoma (PCA) pre-operation. METHODS: From January 2010 to October 2023, a total of 187 cases of parotid tumors were recruited, and divided into training cohort (102 PAs and 51 PCAs) and testing cohort (24 PAs and 10 atypical PCAs). Clinical and CT image features of tumor were assessed. Both enhanced CT-derived ECV and AEF were calculated. Univariate analysis identified variables with statistically significant differences between the two subgroups in the training cohort. Multivariate logistic regression analysis with the forward variable selection method was used to build four models (clinical model, clinical model+ECV, clinical model+AEF, and combined model). Diagnostic performances were evaluated using receiver operating characteristic (ROC) curve analyses. Delong's test compared model differences, and calibration curve and decision curve analysis (DCA) assessed calibration and clinical application. RESULTS: Age and boundary were chosen to build clinical model, and to construct its ROC curve. Amalgamating the clinical model, ECV, and AEF to establish a combined model demonstrated superior diagnostic effectiveness compared to the clinical model in both the training and test cohorts (AUC = 0.888, 0.867). There was a significant statistical difference between the combined model and the clinical model in the training cohort (p = 0.0145). CONCLUSIONS: ECV and AEF are helpful in differentiating PA and atypical PCA, and integrating clinical and CT image features can further improve the diagnostic performance.

Basilar artery fenestration detected with CT angiography.

OBJECTIVES: To analyse the characteristics of basilar artery (BA) fenestrations and their coexistence with aneurysms and other anomalies in a massive cases by computed tomographic angiography (CTA). METHODS: A total of 5,657 sequential cerebral CTA images performed from January 2006 to February 2012 were reviewed. CTA images were obtained from the raw datasets by using volume rendering and maximal intensity projection reconstruction. RESULTS: One hundred and thirty-two (2.33 %) BA fenestrations were detected with CTA, and most common at the proximal segment (n = 124). BA fenestration-associated aneurysms were found in 34 cases and 7 located at the posterior circulation, and the frequency of posterior circulation aneurysms was significantly different in patients with and without BA fenestrations (P = 0.025). Other associated anomalies included arteriovenous malformation (n = 7) and moyamoya disease (n = 6). BA fenestrations were classified into Type I (74 cases), Type II (15 cases), Type III (41 cases) and Type IV (2 cases). A significant difference was observed between Types II + III associated with convex-lens-like and slit-like fenestrations (P = 0.008). CONCLUSIONS: BA fenestrations were found in 2.33 % with CTA. They were significantly more often associated with posterior circulation aneurysms than those without BA fenestration. The anterior inferior cerebral artery (AICA) tends to originate more often from convex-lens-like fenestration than slit-like. KEY POINTS: • Basilar artery fenestrations were found in 2.33 % of patients undergoing CT angiography. • Fenestrations were seen more often in the lower third with slit-like configurations. • No obvious relationship exists between basilar artery fenestration and aneurysm formation. • Basilar artery fenestrations perhaps predispose a patient to posterior circulation aneurysm formation. • The AICA tends to originate more often from convex-lens-like than slit-like fenestrations.

Effects of home-based pulmonary rehabilitation with a metronome-guided walking pace in chronic obstructive pulmonary disease.

Despite documented efficacy and recommendations, pulmonary rehabilitation (PR) in chronic obstructive pulmonary disease (COPD) has been underutilized. Home-based PR was proposed as an alternative, but there were limited data. The adequate exercise intensity was also a crucial issue. The aim of this study was to investigate the effects of home-based PR with a metronome-guided walking pace on functional exercise capacity and health-related quality of life (HRQOL) in COPD. The subjects participated in a 12-week home-based PR program. Exercise intensity was initially determined by cardiopulmonary exercise test, and was readjusted (the interval of metronome beeps was reset) according to submaximal endurance test. Six-minute walk test, pulmonary function test, cardiopulmonary exercise test, and St. George's Respiratory Questionnaire (SGRQ) were done before and after the 12-week program, and at 6 months after completion of rehabilitation. Thirty-three patients participated in the program. Six-minute walking distance was significantly increased (48.8 m; P = 0.017) and the SGRQ score was also improved (-15; P < 0.001) over the six-month follow-up period after rehabilitation. There were no significant differences in pulmonary function and peak exercise parameters. We developed an effective home-based PR program with a metronome-guided walking pace for COPD patients. This rehabilitation program may improve functional exercise capacity and HRQOL.

Genetic variations of CYP3A4 on the metabolism of itraconazole in vitro.

Itraconazole is a triazole anti-infective drug that has been proven to prevent and treat a variety of fungal and viral infections and has been considered to be a potential therapeutic remedy for COVID-19 treatment. In this study, we aimed to completely evaluate the impacts of Cytochrome P450 3A4 (CYP3A4) variant proteins and drug interactions on the metabolism of itraconazole in recombinant insect microsomes, and to characterize the potential mechanism of substrate selectivity. Incubations with itraconazole (0.2-15 µM) in the presence/absence of lopinavir or darunavir were assessed by CYP3A4 variants, and the metabolite hydroxyitraconazole concentrations were measured by UPLC-MS/MS. Our data showed that when compared with CYP3A4.1, 4 variants (CYP3A4.9, .10, .28 and .34) displayed no significant differences, and 3 variants (CYP3A4.14, .15 and .19) exhibited increased intrinsic clearance (CLint), whereas the remaining 17 variant proteins showed decreased enzyme activities for the catalysis of itraconazole. Moreover, the inhibitory effects of lopinavir and darunavir on itraconazole metabolism varied in different degrees. Furthermore, different changed trend of the kinetic parameters in ten variants (CYP3A4.5, .9, .10, .16, .19, .24, .28, .29, .31, and .33) were observed, especially CYP3A4.5 and CYP3A4.16, and this may be related to the metabolic site-heme iron atom distance. In the present study, we functionally analyzed the effects of 25 CYP3A4 protein variants on itraconazole metabolism for the first time, and provided comprehensive data on itraconazole metabolism in vitro. This may help to better assess the metabolism and elimination of itraconazole in clinic to improve the safety and efficacy of its clinical treatment and also provide new possibilities for the treatment of COVID-19.

An ultrasound-based radiomics model for survival prediction in patients with endometrial cancer.

PURPOSE: To establish a nomogram integrating radiomics features based on ultrasound images and clinical parameters for predicting the prognosis of patients with endometrial cancer (EC). MATERIALS AND METHODS: A total of 175 eligible patients with ECs were enrolled in our study between January 2011 and April 2018. They were divided into a training cohort (n = 122) and a validation cohort (n = 53). Least absolute shrinkage and selection operator (LASSO) regression were applied for selection of key features, and a radiomics score (rad-score) was calculated. Patients were stratified into high risk and low-risk groups according to the rad-score. Univariate and multivariable COX regression analysis was used to select independent clinical parameters for disease-free survival (DFS). A combined model based on radiomics features and clinical parameters was ultimately established, and the performance was quantified with respect to discrimination and calibration. RESULTS: Nine features were selected from 1130 features using LASSO regression in the training cohort, which yielded an area under the curve (AUC) of 0.823 and 0.792 to predict DFS in the training and validation cohorts, respectively. Patients with a higher rad-score were significantly associated with worse DFS. The combined nomogram, which was composed of clinically significant variables and radiomics features, showed a calibration and favorable performance for DFS prediction (AUC 0.893 and 0.885 in the training and validation cohorts, respectively). CONCLUSION: The combined nomogram could be used as a tool in predicting DFS and may assist individualized decision making and clinical treatment.

Superwettable Biosensor for Disease Biomarker Detection.

Bioinspired superwettable materials have aroused wide interests in recent years for their promising application fields from service life to industry. As one kind of emerging application, the superwettable surfaces used to fabricate biosensors for the detection of disease biomarkers, especially tumor biomarkers, have been extensively studied. In this mini review, we briefly summarized the sensing strategy for disease biomarker detection based on superwettable biosensors, including fluorescence, electrochemistry, surface-enhanced Raman scattering, and visual assays. Finally, the challenges and direction for future development of superwettable biosensors are also discussed.

Bio-inspired Superwettable Surface for the Detection of Cancer Biomarker: A Mini Review.

Inspired by nature, superwettable material-based biosensors have aroused wide interests due to their potential in cancer biomarker detection. This mini review mainly summarized the superwettable materials as novel biosensing substrates for the development of evaporation-induced enrichment-based signal amplification and visual biosensing method. Biosensing applications based on the superhydrophobic surfaces, superwettable micropatterned surfaces, and slippery lubricant-infused porous surfaces for various cancer biomarker detections were described in detail. Finally, an insight of remaining challenges and perspectives of superwettable biosensor is proposed.

Current Status of Physical Activity in South Korea.

The health benefits of physical activity have been well established. However, more than a quarter of the adult population in the world is insufficiently active (not performing at least 150 minutes of moderate-intensity physical activity per week, 75 minutes of vigorous-intensity physical activity per week, or any equivalent combination of the two), and there has been little improvement since 2001. In South Korea, the prevalence of insufficient physical activity was 54.4% in adults and 94.1% in adolescents in 2020. There was continuous decrease in the prevalence of sufficient aerobic physical activity, from 58.3% in 2014 to 45.6% in 2020. However, daily duration of sedentary behavior increased from 7.5 to 8.6 hours in the same period. Interventions to promote physical activity are necessary in various fields including clinical and policy approaches. As physical activity has decreased during the coronavirus disease 2019 pandemic, safer and more effective strategies to promote physical activity are required.

Analysis of Continuity of Care and Its Related Factors in Diabetic Patients: A Cross-Sectional Study.

BACKGROUND: Continuity of care in primary care settings is crucial for managing diabetes. We aimed to statistically define and analyze continuity factors associated with demographics, clinical workforce, and geographical relationships. METHODS: We used 2014-2015 National Health Insurance Service claims data from the Korean registry, with 39,096 eligible outpatient attendance. We applied multivariable logistic regression to analyze factors that may affect the continuity of care indices for each patient: the most frequent provider continuity index (MFPCI), modified-modified continuity index (MMCI), and continuity of care index (COCI). RESULTS: The mean continuity of care indices were 0.90, 0.96, and 0.85 for MFPCI, MMCI and COCI, respectively. Among patient factors, old age >80 years (MFPCI: odds ratio [OR], 0.81; 95% confidence interval [CI], 0.74-0.89; MMCI: OR, 0.84; 95% CI, 0.76-0.92; and COCI: OR, 0.81; 95% CI, 0.74-0.89) and mild disability were strongly associated with lower continuity of care. Another significant factor was the residential area: the farther the patients lived from their primary care clinic, the lower the continuity of diabetes care (MFPCI: OR, 0.74; 95% CI, 0.70-0.78; MMCI: OR, 0.70; 95% CI, 0.66-0.73; and COCI: OR, 0.74; 95% CI, 0.70-0.78). CONCLUSION: The geographical proximity of patients' residential areas and clinic locations showed the strongest correlation as a continuity factor. Further efforts are needed to improve continuity of care to address the geographical imbalance in diabetic care.

An MRI-based radiomics signature and clinical characteristics for survival prediction in early-stage cervical cancer.

OBJECTIVES: To investigate the prognostic role of magnetic resonance imaging (MRI)-based radiomics signature and clinical characteristics for overall survival (OS) and disease-free survival (DFS) in the early-stage cervical cancer. METHODS: A total of 207 cervical cancer patients (training cohort: n = 144; validation cohort: n = 63) were enrolled. 792 radiomics features were extracted from T2W and diffusion-weighted imaging (DWI). 19 clinicopathological parameters were collected from the electronic medical record system. Least absolute shrinkage and selection operator (LASSO) regression analysis was used to select significant features to construct prognostic model for OS and DFS. Kaplan-Meier (KM) analysis and log-rank test were applied to identify the association between the radiomics score (Rad-score) and survival time. Nomogram discrimination and calibration were evaluated as well. Associations between radiomics features and clinical parameters were investigated by heatmaps. RESULTS: A radiomics signature derived from joint T2W and DWI images showed better prognostic performance than that from either T2W or DWI image alone. Higher Rad-score was associated with worse OS (p < 0.05) and DFS (p < 0.05) in the training and validation set. The joint models outperformed both radiomics model and clinicopathological model alone for 3-year OS and DFS estimation. The calibration curves reached an agreement. Heatmap analysis demonstrated significant associations between radiomics features and clinical characteristics. CONCLUSIONS: The MRI-based radiomics nomogram showed a good performance on survival prediction for the OS and DFS in the early-stage cervical cancer. The prediction of the prognostic models could be improved by combining with clinical characteristics, suggesting its potential for clinical application. ADVANCES IN KNOWLEDGE: This is the first study to build the radiomics-derived models based on T2W and DWI images for the prediction of survival outcomes on the early-stage cervical cancer patients, and further construct a combined risk scoring system incorporating the clinical features.

Effect of MED-02 Containing Two Probiotic Strains, Limosilactobacillus fermentum MG4231 and MG4244, on Body Fat Reduction in Overweight or Obese Subjects: A Randomized, Multicenter, Double-Blind, Placebo-Controlled Study.

MED-02 is a complex supplement containing two probiotic strains, Limosilactobacillus fermentum MG4231 and MG4244, isolated from humans. The anti-obesity effects and safety profile of MED-02 were assessed in overweight and obese subjects. In this randomized, double-blinded, placebo-controlled, multicenter study, 100 healthy obese and overweight subjects aged 19-65 years with a body mass index (BMI) between 25 and 31.9 kg/m2 were recruited and randomized to receive a placebo or MED-02 (5 × 109 CFU/day). After 12 weeks of consumption, body fat mass (-1166.82 g vs. -382.08 g; p = 0.024) and body fat percentage (-0.85% vs. -0.11%; p = 0.030), as evaluated by dual-energy X-ray absorptiometry (DEXA) and body weight (-2.06 kg vs. -1.22 kg; p = 0.041), were significantly reduced in the MED-02 group compared to the placebo group. The safety profile did not differ among the groups. No serious adverse effects were observed in either group. These results suggest that MED-02 is a safe and beneficial probiotics that reduces body fat and body weight in overweight or obese individuals.

Analysis of the Comprehensiveness of Primary Care Clinics in Korea.

BACKGROUND: In the Republic of Korea, which medical specialties should take the responsibility for primary care and what the role of primary care should be are still unclear. In this study, we focused on the comprehensiveness of primary care to identify related factors. METHODS: The National Health Insurance Service (NHIS)-National Sample Cohort is a population-based cohort, sampled in the 2002 NHIS database and followed up until 2015. We used data collected from January 2014 to December 2015, including 20,423,832 outpatient visits in 19,557 office-based clinics. The Korean government has designated 52 simple or minor disease groups (SMDGs) to enhance the experience of patients who attend primary care for managing those diseases. We assessed comprehensiveness for each clinic as the number of SMDGs treated in each clinic for 2 years. We also identified the factors related to higher comprehensiveness, using logistic regression for analysis. RESULTS: The clinics included in the study had provided treatment for an average of 14 SMDGs during a 2-year period. Compared to general practitioners, internal medicine physicians presented higher comprehensiveness with an odds ratio (OR) of 2.29 (95% confidence interval [CI], 2.03-2.59), and family medicine physicians illustrated higher comprehensiveness (OR, 4.96; 95% CI, 3.59-6.83). Other specialties showed lower comprehensiveness than general practitioners. Clinics located in the capital city and metropolitan area tended to have lower comprehensiveness. Clinics hiring more doctors and having hospitalization facility showed higher comprehensiveness. CONCLUSION: General physician, internal medicine, and family medicine are the fields providing comprehensive medical care in Korea. Clinics located in metropolitan area and capital city show lower comprehensiveness. The number of physicians is related to higher comprehensiveness of clinics.

Predicting intraventricular hemorrhage growth with a machine learning-based, radiomics-clinical model.

We constructed a radiomics-clinical model to predict intraventricular hemorrhage (IVH) growth after spontaneous intracerebral hematoma. The model was developed using a training cohort (N=626) and validated with an independent testing cohort (N=270). Radiomics features and clinical predictors were selected using the least absolute shrinkage and selection operator (LASSO) method and multivariate analysis. The radiomics score (Rad-score) was calculated through linear combination of selected features multiplied by their respective LASSO coefficients. The support vector machine (SVM) method was used to construct the model. IVH growth was experienced by 13.4% and 13.7% of patients in the training and testing cohorts, respectively. The Rad-score was associated with severe IVH and poor outcome. Independent predictors of IVH growth included hypercholesterolemia (odds ratio [OR], 0.12 [95%CI, 0.02-0.90]; p=0.039), baseline Graeb score (OR, 1.26 [95%CI, 1.16-1.36]; p<0.001), time to initial CT (OR, 0.70 [95%CI, 0.58-0.86]; p<0.001), international normalized ratio (OR, 4.27 [95%CI, 1.40, 13.0]; p=0.011), and Rad-score (OR, 2.3 [95%CI, 1.6-3.3]; p<0.001). In the training cohort, the model achieved an AUC of 0.78, sensitivity of 0.83, and specificity of 0.66. In the testing cohort, AUC, sensitivity, and specificity were 0.71, 0.81, and 0.64, respectively. This radiomics-clinical model thus has the potential to predict IVH growth.

Characteristic analysis on susceptibility weighted imaging of intravitreous foreign body of autologous eyelashes in rabbits.

OBJECTIVE: To explore the characteristics of susceptibility weighted imaging (SWI) of the intravitreous foreign body of autologous eyelashes in rabbits. METHODS: A total of 12 New Zealand white rabbits, either sex, weighing 2.5-3.5 kg, and provided by the Experimental Animal Center of Henan Province were employed in this study. For each rabbit, 5 autologous eyelashes (1 cm in length and 0.2-0.3 mm in diameter) were implanted into the right ocular vitreum, while the left control ocular vitreum received sham operation but nothing was implanted. SWI sequential test was made 2 hours postoperatively. Then the rabbits were killed and the specimens of the vitreous bodies of the rabbits were obtained. Hematoxylin and eosin staining and histological examinations were performed. RESULTS: The autologous eyelashes in 8 ocular vitreums of rabbits showed linear low signal intensity on the magnitude images and susceptibility weighted images, but linear high signal intensity on the phase images. Among the 12 experimental rabbits, 5 eyelashes in the right vitreum were completely shown in 3 rabbits, partly shown in 5 rabbits (2 eyelashes shown in 3 rabbits and 3 eyelashes shown in 2 rabbits), and not shown in 4 rabbits. CONCLUSIONS: SWI of the foreign body of intravitreous autologous eyelashes in rabbits has its own characteristics. The combined application of SWI sequential magnitude images, susceptibility weighted images and phase images is helpful to the detection and diagnosis of intravitreous autologous eyelashes in rabbits.

In vivo tracing of superparamagnetic iron oxide-labeled bone marrow mesenchymal stem cells transplanted for traumatic brain injury by susceptibility weighted imaging in a rat model.

OBJECTIVE: To label rat bone marrow mesenchymal stem cells (BMSCs) with superparamagnetic iron oxide (SPIO) in vitro, and to monitor the survival and location of these labeled BMSCs in a rat model of traumatic brain injury (TBI) by susceptibility weighted imaging (SWI) sequence. METHODS: BMSCs were cultured in vitro and then labeled with SPIO. Totally 24 male Sprague Dawley (SD) rats weighing 200-250 g were randomly divided into 4 groups: Groups A-D (n equal to 6 for each group). Moderate TBI models of all the rats were developed in the left hemisphere following Feeney's method. Group A was the experimental group and stereotaxic transplantation of BMSCs labeled with SPIO into the region nearby the contusion was conducted in this group 24 hours after TBI modeling. The other three groups were control groups with transplantation of SPIO, unlabeled BMSCs and injection of nutrient solution respectively conducted in Groups B, C and D at the same time. Monitoring of these SPIO-labeled BMSCs by SWI was performed one day, one week and three weeks after implantation. RESULTS: Numerous BMSCs were successfully labeled with SPIO. They were positive for Prussian blue staining and intracytoplasm positive blue stained particles were found under a microscope (200). Scattered little iron particles were observed in the vesicles by electron microscopy (5000). MRI of the transplantation sites of the left hemisphere demonstrated a low signal intensity on magnitude images, phase images and SWI images for all the test rats in Group A, and the lesion in the left parietal cortex demonstrated a semicircular low intensity on SWI images, which clearly showed the distribution and migration of BMSCs in the first and third weeks. For Group B, a low signal intensity by MRI was only observed on the first day but undetected during the following examination. No signals were observed in Groups C and D at any time points. CONCLUSION: SWI sequence in vivo can consecutively and noninvasively trace and demonstrate the status and distribution of BMSCs labeled with SPIO in the brain of TBI model rats.

Penumbra-based radiomics signature as prognostic biomarkers for thrombolysis of acute ischemic stroke patients: a multicenter cohort study.

BACKGROUND AND PURPOSE: This study aimed at developing a radiomics signature (R score) as prognostic biomarkers based on penumbra quantification and to validate the radiomics nomogram to predict the clinical outcomes for thrombolysis for acute ischemic stroke (AIS) patients. METHODS: In total, 168 patients collected from seven centers were retrospectively included. A score of mismatch was defined as MIS. Based on a short-term clinical label, 456 radiomics features were evaluated with feature selection methods. R score was constructed with the selected features. To compare the predictive capabilities of the clinical factors, MIS, and R score, three nomograms were developed and evaluated, according to the short-term clinical assessment on day 7. Finally, the radiomics nomogram was validated by predicting the 3-month clinical outcomes of AIS patients, in an external cohort. RESULTS: R scores were found to be significantly higher in patients with favorable clinical outcomes in both training and validation datasets. The predictive value of the radiomics nomogram estimating favorable clinical outcomes was modest, with a concordance index (C-index) of 0.695 [95% confidence interval (CI) 0.667-0.723) in an external validation dataset. In addition, the area under curve (AUC) of the radiomics nomogram predicting favorable clinical outcome reached 0.886 (95% CI 0.809-0.963) on day 7 and 0.777 (95% CI 0.666-0.888) at 3 months. CONCLUSIONS: The radiomics signature is an independent biomarker for estimating the clinical outcomes in AIS patients. By improving the individualized prediction of the clinical outcome for AIS patients 3 months after onset, the radiomics nomogram adds more value to the current clinical decision-making process.