Evaluation of Ultrafast Wave-CAIPI MPRAGE for Visual Grading and Automated Measurement of Brain Tissue Volume

BACKGROUND AND PURPOSE

Volumetric brain MR imaging typically has long acquisition times. We sought to evaluate an ultrafast MPRAGE sequence based on Wave-CAIPI (Wave-MPRAGE) compared with standard MPRAGE for evaluation of regional brain tissue volumes.

MATERIALS AND METHODS

We performed scan-rescan experiments in 10 healthy volunteers to evaluate the intraindividual variability of the brain volumes measured using the standard and Wave-MPRAGE sequences. We then evaluated 43 consecutive patients undergoing brain MR imaging. Patients underwent 3T brain MR imaging, including a standard MPRAGE sequence (acceleration factor [R] = 2, acquisition time [TA] = 5.2 minutes) and an ultrafast Wave-MPRAGE sequence (R = 9, TA = 1.15 minutes for the 32-channel coil; R = 6, TA = 1.75 minutes for the 20-channel coil). Automated segmentation of regional brain volume was performed. Two radiologists evaluated regional brain atrophy using semiquantitative visual rating scales.

RESULTS

The mean absolute symmetrized percent change in the healthy volunteers participating in the scan-rescan experiments was not statistically different in any brain region for both the standard and Wave-MPRAGE sequences. In the patients undergoing evaluation for neurodegenerative disease, the Dice coefficient of similarity between volumetric measurements obtained from standard and Wave-MPRAGE ranged from 0.86 to 0.95. Similarly, for all regions, the absolute symmetrized percent change for brain volume and cortical thickness showed <6% difference between the 2 sequences. In the semiquantitative visual comparison, the differences between the 2 radiologists' scores were not clinically or statistically significant.

CONCLUSIONS

Brain volumes estimated using ultrafast Wave-MPRAGE show low intraindividual variability and are comparable with those estimated using standard MPRAGE in patients undergoing clinical evaluation for suspected neurodegenerative disease.

Hypomethylation of Notch1 DNA is associated with the occurrence of uveitis

Uveitis is a serious intra-ocular inflammatory disease that can lead to visual impairment even blindness worldwide. Notch signaling can regulate the differentiation of naive CD4⁺ T cells, influencing the development of uveitis. DNA methylation is closely related to the autoimmune diseases. In this study, we measured the Notch1 DNA methylation level, determined the Notch1 and related DNA methylases mRNA expression and evaluated the ratio of T helper type 17 regulatory T cell (Th17/T_reg ) in peripheral blood mononuclear cells (PBMCs) from uveitis patients and normal control subjects; we also tested the levels of relevant inflammatory cytokines in serum from the participants. Results indicated that compared with those in normal control individuals, the expression of ten-eleven translocation 2 (TET2) and Notch1 mRNA is elevated in uveitis patients, whereas the methylation level in Notch1 DNA promotor region [-842 ~ -646 base pairs (bp)] is down-regulated, and is unrelated to anatomical location. Moreover, the Th17/T_reg ratio is up-regulated in PBMCs from uveitis patients, accompanied by the elevated levels of proinflammatory cytokines [e.g. interleukin (IL)-2, IL-6, IL-17 and interferon (IFN)-γ] in serum from uveitis patients. These findings suggest that the over-expression of TET2 DNA demethylase may lead to hypomethylation of Notch1, activate the Notch1 signaling, induce naive CD4⁺ T cells to differentiate theTh17 subset and thus disturb the balance of the Th17/T_reg ratio in uveitis patients. Overall, hypomethylation of Notch1 DNA is closely associated with the occurrence of uveitis. Our study preliminarily reveals the underlying mechanism for the occurrence of uveitis related to the hypomethylation of Notch1 DNA, providing a novel therapeutic strategy against uveitis in clinical practice.

Non-invasive prediction of fetal growth restriction by whole-genome promoter profiling of maternal plasma DNA: a nested case-control study

Objective

To predict fetal growth restriction (FGR) by whole‐genome promoter profiling of maternal plasma.

Design

Nested case–control study.

Setting

Hospital‐based.

Population or Sample

810 pregnancies: 162 FGR cases and 648 controls.

Methods

We identified gene promoters with a nucleosome footprint that differed between FGR cases and controls based on maternal plasma cell‐free DNA (cfDNA) nucleosome profiling. Optimal classifiers were developed using support vector machine (SVM) and logistic regression (LR) models.

Main outcome measures

Genes with differential coverages in promoter regions through the low‐coverage whole‐genome sequencing data analysis among FGR cases and controls. Receiver operating characteristic (ROC) analysis (area under the curve [AUC], accuracy, sensitivity and specificity) was used to evaluate the performance of classifiers.

Results

Through the low‐coverage whole‐genome sequencing data analysis of FGR cases and controls, genes with significantly differential DNA coverage at promoter regions (−1000 to +1000 bp of transcription start sites) were identified. The non‐invasive ‘FGR classifier 1’ (C_FGR1) had the highest classification performance (AUC, 0.803; 95% CI 0.767–0.839; accuracy, 83.2%) was developed based on 14 genes with differential promoter coverage using a support vector machine.

Conclusions

A promising FGR prediction method was successfully developed for assessing the risk of FGR at an early gestational age based on maternal plasma cfDNA nucleosome profiling.

Tweetable abstract

A promising FGR prediction method was successfully developed, based on maternal plasma cfDNA nucleosome profiling.

A promising FGR prediction method was successfully developed, based on maternal plasma cfDNA nucleosome profiling.

[Changes of serum E2 and Otolin-1 levels in postmenopausal women with BPPV]

Objective:To investigate the changes of serum estradiol（E2） and otolith structural protein Otolin-1 levels in postmenopausal women with benign paroxysmal positional vertigo（BPPV）. Method:Forty postmenopausal women diagnosed as primary BPPV were selected as the experimental group. Meanwhile, 40 postmenopausal women without vertigo during the same time were selected as the control group. 4 ml of fasting peripheral venous blood was extracted in the morning, and E2 and Otolin-1 protein levels in serum of the two groups were detected by electrochemiluminescence（ECL） and ELISA, respectively. Result:①The serum level of E2 in the experimental group was（29.11±15.11） pg/ml, which was lower than that in the control group（37.18±12.24） pg/ml（P=0.010）. ②The serum level of Otolin-1 in the experimental group was（361.55±186.14） pg/ml, which was significantly higher than that in the control group（282.61±139.98） pg/ml（P=0.035）. ③Spearman correlation analysis was carried out on the serum levels of Otolin-1 and E2 in the experimental group and the control group, respectively, and no correlation was found between them（P=0.403 and 0.363, respectively）. ④In the control group, age was negatively correlated with serum E2 level（P=0.044, r=-0.320）, suggesting that age was only weakly correlated with E2 level. However, in the experimental group, there was no correlation between the two（P=0.148）. ⑤There was no correlation between age and serum Otolin-1 level in the two groups（P=0.705 and 0.076, respectively）. Conclusion:Compared with postmenopausal patients without vertigo, the level of E2 in postmenopausal BPPV patients decreased, but the level of Otolin-1 increased significantly. Therefore, the serum level of Otolin-1 may be used as a bio-marker to assist the diagnosis and efficacy evaluation of postmenopausal women with BPPV.

Interstitial brachytherapy of oral squamous cell carcinoma with ultrasound-guided iodine-125 radioactive seed implantation

OBJECTIVE

In this study, we investigated the clinical effect of interstitial brachytherapy on oral squamous cell carcinoma (OSCC) with ultrasound or CT-guided 125I radioactive seed implantation.

PATIENTS AND METHODS

116 patients with advanced oral squamous cell carcinoma, who received initial treatment or retreatment, were enrolled. Therein, 35 patients in the control group were treated with external radiation, systemic chemotherapy or conservative treatment, 41 patients in the ultrasound group were treated with ultrasound-guided125I radioactive seed interstitial implantation brachytherapy, and 40 patients in the CT group were treated with CT-guided 125I radioactive seed interstitial implantation. The median follow-up time was 15.0 months. The clinical outcomes were compared.

RESULTS

At the time of one month after treatment, the tumor diameters of the ultrasound group and the CT group were significantly decreased (p<0.05), which were less than the control group (p<0.05), and there was no difference in comparison between the ultrasound group and the CT group (p>0.05). At the time of one month after treatment, the effective rates were significantly higher in the ultrasound group and the CT group than the control group (p<0.001), and there was no difference in comparison between the ultrasound group and the CT group. And there was no difference in comparison of complication between these two groups (p>0.05). At the time of one month after treatment, the VAS scores of pain were significantly lower in the ultrasound group and the CT group than the control group (p<0.05). There were no differences in comparisons of T lymphocyte subset percentages before and after treatment (p>0.05), and T lymphocyte subset percentages in the control group were significantly decreased (p<0.05). The progression-free survivals, median survival times, and survival rates were significantly higher in the ultrasound group and the CT group than those in the control group (p<0.05), and there were no differences in comparisons between the ultrasound group and the CT group (p>0.05).

CONCLUSIONS

Both ultrasound and CT-guided iodine-125 radioactive seed interstitial implantation brachytherapy in the treatment of OSCC  can achieve better short-term and long-term clinical effects.

Plasma long non-coding RNAs (lncRNAs) serve as potential biomarkers for predicting breast cancer

OBJECTIVE

Recent studies have suggested that lncRNAs play important regulatory roles in occurrence and progression of many cancers including breast cancer. However, only a small number of lncRNAs have proved to be related to breast cancer. Moreover, the effect of lncRNAs on breast cancer is yet unclear. We aimed at examining whether the expression level of these lncRNAs in our breast cancer patients could be different to normal people, and whether these lncRNAs could serve as potential biomarkers for the diagnosis of breast cancer.

PATIENTS AND METHODS

We selected twelve lncRNAs as the research targets, which were previously found to be abnormally expressed in plasma of other cancers. The expression levels of these lncRNAs were measured by Quantitative Real-time Polymerase Chain Reaction (qRT-PCR) and compared between breast cancer patients and normal people.

RESULTS

The expression levels of plasma lncRNAs (H19, HOTAIR, and RP11-445H22.4) are found to increase significantly in breast cancer patients. The expression levels of other 9 lncRNAs were no significant changed compared with normal people.

CONCLUSIONS

lncRNAs may be related to the occurrence of breast cancer and serve as potential biomarkers for its diagnosis.

Imaging G-Ratio in Multiple Sclerosis Using High-Gradient Diffusion MRI and Macromolecular Tissue Volume

BACKGROUND AND PURPOSE

Remyelination represents an area of great therapeutic interest in multiple sclerosis but currently lacks a robust imaging marker. The purpose of this study was to use high-gradient diffusion MRI and macromolecular tissue volume imaging to obtain estimates of axonal volume fraction, myelin volume fraction, and the imaging g-ratio in patients with MS and healthy controls and to explore their relationship to neurologic disability in MS.

MATERIALS AND METHODS

Thirty individuals with MS (23 relapsing-remitting MS, 7 progressive MS) and 19 age-matched healthy controls were scanned on a 3T MRI scanner equipped with 300 mT/m maximum gradient strength using a comprehensive multishell diffusion MRI protocol. Macromolecular tissue volume imaging was performed to quantify the myelin volume fraction. Diffusion data were fitted to a 3-compartment model of white matter using a spheric mean approach to yield estimates of axonal volume fraction. The imaging g-ratio was calculated from the ratio of myelin volume fraction and axonal volume fraction. Imaging metrics were compared between groups using 2-sided t tests with a Bonferroni correction.

RESULTS

The mean g-ratio was significantly elevated in lesions compared with normal-appearing WM (0.74 vs 0.67, P < .001). Axonal volume fraction (0.17 vs 0.23, P < .001) and myelin volume fraction (0.17 vs 0.25, P < .001) were significantly lower in lesions than normal-appearing WM. Myelin volume fraction was lower in normal-appearing WM compared with that in healthy controls (0.25 vs 0.27, P = .009). Disability, as measured by the Expanded Disability Status Scale, was significantly associated with myelin volume fraction (β = -40.5, P = .001) and axonal volume fraction (β = -41.0, P = .016) in normal-appearing WM.

CONCLUSIONS

The imaging g-ratio may serve as a biomarker for the relative degree of axonal and myelin loss in MS.

Reduced SPOCK1 expression inhibits non-small cell lung cancer cell proliferation and migration through Wnt/β-catenin signaling

OBJECTIVE

Accumulating evidence suggests that SPARC/osteonectin, cwcv, and kazal-like domain proteoglycan 1 (SPOCK1) contributes to the initiation and progression of human cancers. However, little is known about the function mechanisms of SPOCK1 in non-small cell lung cancer (NSCLC). The aim of this study was to investigate the molecular mechanism of SPOCK1 in NSCLC.

PATIENTS AND METHODS

The expression levels of SPOCK1 in NSCLC tissues and cell lines were analyzed by qRT-PCR and Western blotting. The proliferative activity of NSCLC cells was determined by MTT and colony formation assays. The transwell assay was used to examine the cell migration and invasive ability. To study the impact of SPOCK1 on Wnt/β‑catenin signaling, we further performed Western blotting for related proteins in this pathway.

RESULTS

We observed that the expression of SPOCK1 at both protein and mRNA levels was also increased in human NSCLC tissues and cell lines. Functionally, down-regulation of SPOCK1 in NSCLC cells markedly suppressed cell proliferation, colony formation, migration and invasion in vitro. Mechanistically, we found that indicated the activation of Wnt/β-catenin pathway was suppressed by SPOCK1 silencing.

CONCLUSIONS

The expression of SPOCK1 served as a tumor promoter, possibly through the Wnt/β-catenin signaling pathway in NSCLC. Targeting SPOCK1 could be a potential therapeutic strategy in NSCLC.

Janus particles: design, preparation, and biomedical applications

Janus particles with an anisotropic structure have emerged as a focus of intensive research due to their diverse composition and surface chemistry, which show excellent performance in various fields, especially in biomedical applications. In this review, we briefly introduce the structures, composition, and properties of Janus particles, followed by a summary of their biomedical applications. Then we review several design strategies including morphology, particle size, composition, and surface modification, that will affect the performance of Janus particles. Subsequently, we explore the synthetic methodologies of Janus particles, with an emphasis on the most prevalent synthetic method (surface nucleation and seeded growth). Following this, we highlight Janus particles in biomedical applications, especially in drug delivery, bio-imaging, and bio-sensing. Finally, we will consider the current challenges the materials face with perspectives in the future directions.

A prospective study of focal brain atrophy, mobility and fitness

BACKGROUND

The parallel decline of mobility and cognition with ageing is explained in part by shared brain structural changes that are related to fitness. However, the temporal sequence between fitness, brain structural changes and mobility loss has not been fully evaluated.

METHODS

Participants were from the Baltimore Longitudinal Study of Aging, aged 60 or older, initially free of cognitive and mobility impairments, with repeated measures of fitness (400-m time), mobility (6-m gait speed) and neuroimaging markers over 4 years (n = 332). Neuroimaging markers included volumes of total brain, ventricles, frontal, parietal, temporal and subcortical motor areas, and corpus callosum. Autoregressive models were used to examine the temporal sequence of each brain volume with mobility and fitness, adjusted for age, sex, race, body mass index, height, education, intracranial volume and APOE ɛ4 status.

RESULTS

After adjustment, greater volumes of total brain and selected frontal, parietal and temporal areas, and corpus callosum were unidirectionally associated with future faster gait speed over and beyond cross-sectional and autoregressive associations. There were trends towards faster gait speed being associated with future greater hippocampus and precuneus. Higher fitness was unidirectionally associated with future greater parahippocampal gyrus and not with volumes in other areas. Smaller ventricle predicted future higher fitness.

CONCLUSION

Specific regional brain volumes predict future mobility impairment. Impaired mobility is a risk factor for future atrophy of hippocampus and precuneus. Maintaining fitness preserves parahippocampal gyrus volume. Findings provide new insight into the complex and bidirectional relationship between the parallel decline of mobility and cognition often observed in older persons.

[The etiological analysis of 260 hospitalized cases with bilateral adrenal lesions]

Objective: To summarize the etiologies of bilateral adrenal lesions and the changes of the disease profile in hospitalized patients. Methods: Bilateral adrenal lesion screening was conducted in all patients admitted to Peking University Third Hospital from 1994 to 2017. The etiologies and disease profiles of bilateral adrenal lesions were retrospectively analyzed. Results: A total of 260 patients with bilateral adrenal lesions were included in the study. There were 146 males and 114 females with a mean age of (55.4±16.2) years. The most common adrenal lesion was bilateral adrenal hyperplasia (75 cases, 28.8%), followed by bilateral adrenal adenomas (71 cases, 27.3%), metastatic carcinoma (51 cases, 19.6%), discordant bilateral adrenal lesions (27 cases, 10.4%), bilateral pheochromocytomas (13 cases, 5.0%), and others. The clear data of endocrine function evaluation could be found in 184 patients. Among them, 111 cases (60.3%) were nonfunctioning lessions, 34 cases (18.5%) with primary aldosteronism, 15 cases (8.1%) with pheochromocytoma, 13 cases (7.1%) with congenital adrenal hyperplasia, 6 cases (3.3%) with primary hypoadrenocorticism, and 5 cases (2.7%) with Cushing syndrome. Using every 8 years as a period of time, the number of hospitalized patients with bilateral adrenal lesions increased with years in three periods (8, 41 and 211 cases, respectively). Conclusions: The most common cause of bilateral adrenal lesions is adrenal hyperplasia in the hospitalized patients. More than half of bilateral adrenal lesions are nonfunctioning. In functional bilateral lesions, primary aldosteronism and pheochromocytoma account for a large proportion.

A novel mechanism of memory loss in Alzheimer's disease mice via the degeneration of entorhinal-CA1 synapses

The entorhinal cortex (EC) is one of the most vulnerable brain regions that is attacked during the early stage of Alzheimer's disease (AD). Here, we report that the synaptic terminals of pyramidal neurons in the EC layer II (ECII_PN) directly innervate CA1 parvalbumin (PV) neurons (CA1_PV) and are selectively degenerated in AD mice, which exhibit amyloid-β plaques similar to those observed in AD patients. A loss of ECII_PN-CA1_PV synapses disables the excitatory and inhibitory balance in the CA1 circuit and impairs spatial learning and memory. Optogenetic activation of ECII_PN using a theta burst paradigm rescues ECII_PN-CA1_PV synaptic defects and intercepts the decline in spatial learning and memory. These data reveal a novel mechanism of memory loss in AD mice via the selective degeneration of the ECII_PN-CA1_PV pathway.

Network based subcellular proteomics in monocyte membrane revealed novel candidate genes involved in osteoporosis

In this study, label-free-based quantitative subcellular proteomics integrated with network analysis highlighted several candidate genes including P4HB, ITGB1, CD36, and ACTN1 that may be involved in osteoporosis. All of them are predicted as significant membrane proteins with high confidence and enriched in bone-related biological process. The results were further verified in transcriptomic and genomic levels.

INTRODUCTION

Osteoporosis is a metabolic bone disease mainly characterized by low bone mineral density (BMD). As the precursors of osteoclasts, peripheral blood monocytes (PBMs) are supported to be important candidates for identifying genes related to osteoporosis. We performed subcellular proteomics study to identify significant membrane proteins that involved in osteoporosis.

METHODS

To investigate the association between monocytes, membrane proteins, and osteoporosis, we performed label-free quantitative subcellular proteomics in 59 male subjects with discordant BMD levels, with 30 high vs. 29 low BMD subjects. Subsequently, we performed integrated gene enrichment analysis, functional annotation, and pathway and network analysis based on multiple bioinformatics tools.

RESULTS

A total of 1070 membrane proteins were identified and quantified. By comparing the proteins' expression level, we found 36 proteins that were differentially expressed between high and low BMD groups. Protein localization prediction supported the notion that the differentially expressed proteins, P4HB (p = 0.0021), CD36 (p = 0.0104), ACTN1 (p = 0.0381), and ITGB1 (p = 0.0385), are significant membrane proteins. Functional annotation and pathway and network analysis highlighted that P4HB, ITGB1, CD36, and ACTN1 are enriched in osteoporosis-related pathways and terms including "ECM-receptor interaction," "calcium ion binding," "leukocyte transendothelial migration," and "reduction of cytosolic calcium levels." Results from transcriptomic and genomic levels provided additional supporting evidences.

CONCLUSION

Our study strongly supports the significance of the genes P4HB, ITGB1, CD36, and ACTN1 to the etiology of osteoporosis risk.