Altered functional connectivity pattern of hippocampal subfields in individuals with objectively-defined subtle cognitive decline and its association with cognition and cerebrospinal fluid biomarkers.

Recent studies have shown that in the preclinical phase of Alzheimer's disease (AD), subtle cognitive changes can be detected using sensitive neuropsychological measures, and have proposed the concept of objectively-defined subtle cognitive decline (Obj-SCD). We aimed to assess the functional alteration of hippocampal subfields in individuals with Obj-SCD and its association with cognition and pathological biomarkers. Forty-two participants with cognitively normal (CN), 29 with Obj-SCD, and 55 with mild cognitive impairment (MCI) were retrospectively collected from the ADNI database. Neuropsychological performance, functional MRI, and cerebrospinal fluid (CSF) data were obtained. We calculated the seed-based functional connectivity (FC) of hippocampal subfields (cornu ammonis1 [CA1], CA2/3/dentate gyrus [DG], and subiculum) with whole-brain voxels. Additionally, we analyzed the correlation between FC values of significantly altered regions and neuropsychological performance and CSF biomarkers. The Obj-SCD group showed lower FC between left CA1-CA2/3/DG and right thalamus and higher FC between right subiculum and right superior parietal gyrus (SPG) compared with the CN and MCI groups. In the Obj-SCD group, FC values between left CA2/3/DG and right thalamus were positively associated with Auditory Verbal Learning Test (AVLT) recognition (r = 0.395, p = 0.046) and CSF Aß1-42 levels (r = 0.466, p = 0.019), and FC values between left CA1 and right thalamus were positively correlated with CSF Aß1-42 levels (r = 0.530, p = 0.006). Taken together, dysfunction in CA1-CA2/3/DG subregions suggests subtle cognitive impairment and AD-specific pathological changes in individuals with Obj-SCD. Additionally, increased subiculum connectivity may indicate early functional compensation for subtle cognitive changes.

Increased striatal functional connectivity is associated with improved smoking cessation outcomes: A preliminary study.

The striatum is the critical area of reward processing and has been repeatedly linked to nicotine addiction. However, it remains unclear whether different smoking cessation outcomes (relapse or not) are associated with different functional connectivity changes of the striatum during smoking cessation treatment. A total of 30 treatment-seeking smokers were recruited in the study and underwent magnetic resonance imaging (MRI) scans immediately before and after a 12-week treatment with varenicline. After the 12-week treatment with varenicline, 14 subjects relapsed to smoking (relapsers), whereas 16 not relapsed (nonrelapsers). Changes in resting-state functional connectivity (rsFC) across groups and visits were assessed using repeated measures analysis of covariance (ANCOVA). Significant interaction effects were detected: (1) between left nucleus accumbens (NAc) and left orbitofrontal cortex (OFC), insula, inferior frontal gyrus (IFG), and bilateral precuneus; (2) between right NAc and left insula, IFG, and bilateral dorsolateral prefrontal cortex (DLPFC); and (3) between bilateral putamen and left precuneus. Post hoc region-of-interest analyses in brain areas showing interaction effects indicated significantly decreased rsFC after treatment compared with before treatment in relapsers but opposite longitudinal changes in nonrelapers. These novel findings suggest that increased striatal rsFC is associated with improved smoking cessation outcomes. These striatal functional circuits may serve as potential therapeutic targets for more efficacious treatment of nicotine addiction.

Understanding the association between psychomotor processing speed and white matter hyperintensity: A comprehensive multi-modality MR imaging study.

Cognitive processing speed is crucial for human cognition and declines with aging. White matter hyperintensity (WMH), a common sign of WM vascular damage in the elderly, is closely related to slower psychomotor processing speed. In this study, we investigated the association between WMH and psychomotor speed changes through a comprehensive assessment of brain structural and functional features. Multi-modal MRIs were acquired from 60 elderly adults. Psychomotor processing speeds were assessed using the Trail Making Test Part A (TMT-A). Linear regression analyses were performed to assess the associations between TMT-A and brain features, including WMH volumes in five cerebral regions, diffusivity parameters in the major WM tracts, regional gray matter volume, and brain activities across the whole brain. Hierarchical regression analysis was used to demonstrate the contribution of each index to slower psychomotor processing speed. Linear regression analysis demonstrated that WMH volume in the occipital lobe and fractional anisotropy of the forceps major, an occipital association tract, were associated with TMT-A. Besides, resting-state brain activities in the visual cortex connected to the forceps major were associated with TMT-A. Hierarchical regression showed fractional anisotropy of the forceps major and regional brain activities were significant predictors of TMT-A. The occurrence of WMH, combined with the disruption of passing-through fiber integrity and altered functional activities in areas connected by this fiber, are associated with a decline of psychomotor processing speed. While the causal relationship of this WMH-Tract-Function-Behavior link requires further investigation, this study enhances our understanding of these complex mechanisms.

Interactions between monoamine oxidase A rs1137070 and smoking on brain structure and function in male smokers.

The monoamine oxidase A (MAOA) enzyme metabolizes monoamine neurotransmitters such as dopamine, serotonin and norepinephrine, and its genetic polymorphism (rs1137070) influences its activity level and is associated with smoking behaviors. However, the underlying neural mechanisms of the gene × environment interactions remain largely unknown. In this study, we aimed to explore the interactive effects of the rs1137070 and cigarette smoking on gray matter volume (GMV) and functional connectivity strength (FCS). A total of 81 smokers and 42 nonsmokers were enrolled in the present study. Voxel-based morphometry analysis showed a significant rs1137070 genotype × smoking effect on the GMV of the left orbitofrontal cortex (OFC), such that individuals with risk allele had greater GMV among nonsmokers but not smokers. Meanwhile, rs1137070 variant and nicotine dependence interactively altered the FCS of the right hippocampus, the left inferior parietal lobule (IPL), the left dorsolateral prefrontal cortex and bilateral OFC. In addition, the FCS in the left IPL was correlated with smoking initiation and smoking years in smokers with the risk allele. These findings suggest that MAOA rs1137070 contributes to the susceptibility to nicotine dependence through its influence on brain circuits involved in reward and attention, and interacts with smoking in the progression.

Cerebellar Gray Matter Reductions Associate With Decreased Functional Connectivity in Nicotine-Dependent Individuals.

Introduction: Nicotine dependence (ND) is a chronic, relapsing mental disorder characterized by compulsive cigarette seeking and smoking. Although the cerebellum plays an increasingly implicated role in ND, the exact cerebellar alterations in ND remain unclear. Identifying the localization of these cerebellar abnormalities in ND may help to further understand the role of the cerebellum in ND. Thus, we investigated the structural and functional alterations in the cerebellum in a large sample of smokers using the spatially unbiased infratentorial template (SUIT). Methods: High-resolution structural magnetic resonance imaging (MRI) data were acquired from 85 smokers and 41 nonsmokers. We applied voxel-based morphometry (VBM) and the SUIT cerebellar atlas to compare the cerebellar gray matter (GM) volume between smokers and nonsmokers. Using resting-state functional MRI data, we also performed seed-based functional connectivity (FC) analysis to examine the functional correlates of the GM volume changes. Results: Both VBM and lobular analyses revealed smaller GM volume in the bilateral Crus I in smokers. The GM volume of the left Crus I was inversely correlated with the severity of nicotine dependence as assessed by Fagerström Test for Nicotine Dependence (r = -.268, p = .013). We also found reduced FC between the bilateral Crus I and brain regions involved in the default mode network and motor system, as well as the frontal and temporal cortex in smokers. Conclusions: Our results indicate that decreased cerebellar GM volume and corticocerebellar FC are associated with ND, and these may underlie the core ND phenotypes, including automatized smoking behavior, cognitive, and emotional deficits. Implications: As smoking remains a worldwide public health problem, identifying the related neural alterations may help to understand the pathophysiology of ND. Based on previous findings in the cerebellum, we investigated the localization of the GM differences and related FC changes in ND subjects. Our findings highlight altered corticocerebellar circuits in ND, suggesting an association between the cerebellum and the phenotypes of ND.

Influence of regional iron on the motor impairments of Parkinson's disease: A quantitative susceptibility mapping study.

PURPOSE: Because the roles of striatal-thalamo-cortical and cerebello-thalamo-cortical circuits in the heterogeneous motor impairments of Parkinson's disease (PD) are becoming recognized, this study was designed to investigate the relationships between regional iron in the cardinal subcortical nuclei in these circuits and the different motor impairments. MATERIALS AND METHODS: Sixty-two PD patients and 40 normal subjects were included and accepted for Enhanced T2 -Star Weighted Angiography Scanning (3.0T). According to the Unified Parkinson's Disease Rating Scale, patients were divided into tremor-dominant (PD-TD) and akinetic/rigid-dominant groups (PD-AR). The intergroup differences of magnetic susceptibility in those cardinal nuclei were measured. Correlation analyses between magnetic susceptibility and motor impairments were performed in all patients. RESULTS: Nigral magnetic susceptibility significantly increased for each PD group compared with controls (P < 0.001 for PD-TD; P = 0.001 for PD-AR). Magnetic susceptibility in the dentate nucleus (DN) and red nucleus (RN) for the PD-TD patients were significantly increased compared with controls (P < 0.001 and P = 0.004, respectively). Magnetic susceptibility in these regions was also significantly correlated with tremor severity (r = 0.444, P = 0.001 for DN; r = 0.418, P = 0.001 for RN). Significant correlation between caudate magnetic susceptibility and akinetic/rigid severity were observed (r = -0.322, P = 0.015). CONCLUSION: This study provides evidence that nigral iron accumulation is a common characteristic in PD, while iron accumulation in the DN and RN is correlated with tremor symptoms. Our data also indicate that caudate iron content may be a potential marker for akinetic/rigid progression. LEVEL OF EVIDENCE: 3 J. MAGN. RESON. IMAGING 2017;45:1335-1342.

Altered human brain anatomy in chronic smokers: a review of magnetic resonance imaging studies.

Cigarette smoking is becoming more prevalent in developing countries, such as China, and is the largest single cause of preventable death worldwide. New emerging reports are highlighting how chronic cigarette smoking plays a role in neural dysfunctions, such as cognitive decline. Basic animal experimental studies have shown that rats undergo persistent pathological brain changes after being given chronic levels of nicotine. What is perhaps less appreciated is the fact that chronic cigarette smoking induces subtle anatomical changes in the human brain. Consequently, this chapter aims to summarize and integrate the existing magnetic resonance imaging studies on both gray- and white-matter marcostructural and microstructural changes. The reviewed studies demonstrate that chronic cigarette smoking results in discrete and localized alterations in brain region tissue (both the gray and white matter of different brain regions), which may, in part, be responsible for different neural dysfunctions. In addition, we further discuss the possible pathological and neurobiological mechanisms of these nicotinic effects on the brain tissue. We will also address the limitations of the current studies on this issue and identify opportunities for future research.

Clinical and radiological characteristics of pediatric COVID-19 before and after the Omicron outbreak: a multi-center study.

Introduction: The emergence of the Omicron variant has seen changes in the clinical and radiological presentations of COVID-19 in pediatric patients. We sought to compare these features between patients infected in the early phase of the pandemic and those during the Omicron outbreak. Methods: A retrospective study was conducted on 68 pediatric COVID-19 patients, of which 31 were infected with the original SARS-CoV-2 strain (original group) and 37 with the Omicron variant (Omicron group). Clinical symptoms and chest CT scans were examined to assess clinical characteristics, and the extent and severity of lung involvement. Results: Pediatric COVID-19 patients predominantly had normal or mild chest CT findings. The Omicron group demonstrated a significantly reduced CT severity score than the original group. Ground-glass opacities were the prevalent radiological findings in both sets. The Omicron group presented with fewer symptoms, had milder clinical manifestations, and recovered faster than the original group. Discussion: The clinical and radiological characteristics of pediatric COVID-19 patients have evolved with the advent of the Omicron variant. For children displaying severe symptoms warranting CT examinations, it is crucial to weigh the implications of ionizing radiation and employ customized scanning protocols and protective measures. This research offers insights into the shifting disease spectrum, aiding in the effective diagnosis and treatment of pediatric COVID-19 patients.

Interactions between cigarette smoking and cognitive status on functional connectivity of the cortico-striatal circuits in individuals without dementia: A resting-state functional MRI study.

AIMS: Cigarette smoking is a modifiable risk factor for Alzheimer's disease (AD), and controlling risk factors may curb the progression of AD. However, the underlying neural mechanisms of the effects of smoking on cognition remain largely unclear. Therefore, we aimed to explore the interaction effects of smoking × cognitive status on cortico-striatal circuits, which play a crucial role in addiction and cognition, in individuals without dementia. METHODS: We enrolled 304 cognitively normal (CN) non-smokers, 44 CN smokers, 130 mild cognitive impairment (MCI) non-smokers, and 33 MCI smokers. The mixed-effect analysis was performed to explore the interaction effects between smoking and cognitive status (CN vs. MCI) based on functional connectivity (FC) of the striatal subregions (caudate, putamen, and nucleus accumbens [NAc]). RESULTS: The significant interaction effects of smoking × cognitive status on FC of the striatal subregions were detected in the left inferior parietal lobule (IPL), bilateral cuneus, and bilateral anterior cingulate cortex (ACC). Specifically, increased FC of right caudate to left IPL was found in CN smokers compared with non-smokers. The MCI smokers showed decreased FC of right caudate to left IPL and of right putamen to bilateral cuneus and increased FC of bilateral NAc to bilateral ACC compared with CN smokers and MCI non-smokers. Furthermore, a positive correlation between FC of the NAc to ACC with language and memory was detected in MCI smokers. CONCLUSIONS: Cigarette smoking could affect the function of cortico-striatal circuits in patients with MCI. Our findings suggest that quitting smoking in the prodromal stage of AD may have the potential to prevent disease progression.

Effects of Cigarette Smoking on Resting-State Functional Connectivity of the Nucleus Basalis of Meynert in Mild Cognitive Impairment.

Background: Mild cognitive impairment (MCI) is the prodromal phase of Alzheimer's disease (AD) and has a high risk of progression to AD. Cigarette smoking is one of the important modifiable risk factors in AD progression. Cholinergic dysfunction, especially the nucleus basalis of Meynert (NBM), is the converging target connecting smoking and AD. However, how cigarette smoking affects NBM connectivity in MCI remains unclear. Objective: This study aimed to evaluate the interaction effects of condition (non-smoking vs. smoking) and diagnosis [cognitively normal (CN) vs. MCI] based on the resting-state functional connectivity (rsFC) of the NBM. Methods: After propensity score matching, we included 86 non-smoking CN, 44 smoking CN, 62 non-smoking MCI, and 32 smoking MCI. All subjects underwent structural and functional magnetic resonance imaging scans and neuropsychological tests. The seed-based rsFC of the NBM with the whole-brain voxel was calculated. Furthermore, the mixed effect analysis was performed to explore the interaction effects between condition and diagnosis on rsFC of the NBM. Results: The interaction effects of condition × diagnosis on rsFC of the NBM were observed in the bilateral prefrontal cortex (PFC), bilateral supplementary motor area (SMA), and right precuneus/middle occipital gyrus (MOG). Specifically, the smoking CN showed decreased rsFC between left NBM and PFC and increased rsFC between left NBM and SMA compared with non-smoking CN and smoking MCI. The smoking MCI showed reduced rsFC between right NBM and precuneus/MOG compared with non-smoking MCI. Additionally, rsFC between the NBM and SMA showed a significant negative correlation with Wechsler Memory Scale-Logical Memory (WMS-LM) immediate recall in smoking CN (r = -0.321, p = 0.041). Conclusion: Our findings indicate that chronic nicotine exposure through smoking may lead to functional connectivity disruption between the NBM and precuneus in MCI patients. The distinct alteration patterns on NBM connectivity in CN smokers and MCI smokers suggest that cigarette smoking has different influences on normal and impaired cognition.

Quantitative and semi-quantitative CT assessments of lung lesion burden in COVID-19 pneumonia.

This study aimed to clarify and provide clinical evidence for which computed tomography (CT) assessment method can more appropriately reflect lung lesion burden of the COVID-19 pneumonia. A total of 244 COVID-19 patients were recruited from three local hospitals. All the patients were assigned to mild, common and severe types. Semi-quantitative assessment methods, e.g., lobar-, segmental-based CT scores and opacity-weighted score, and quantitative assessment method, i.e., lesion volume quantification, were applied to quantify the lung lesions. All four assessment methods had high inter-rater agreements. At the group level, the lesion load in severe type patients was consistently observed to be significantly higher than that in common type in the applications of four assessment methods (all the p < 0.001). In discriminating severe from common patients at the individual level, results for lobe-based, segment-based and opacity-weighted assessments had high true positives while the quantitative lesion volume had high true negatives. In conclusion, both semi-quantitative and quantitative methods have excellent repeatability in measuring inflammatory lesions, and can well distinguish between common type and severe type patients. Lobe-based CT score is fast, readily clinically available, and has a high sensitivity in identifying severe type patients. It is suggested to be a prioritized method for assessing the burden of lung lesions in COVID-19 patients.

Abnormal white matter tracts of insula in smokers.

Nicotine addiction is characterized as a neural circuit dysfunction, particularly with regard to the alterations in central reward pathways. The insula, a cortical region that is thought to play a central role in this reward circuitry, has been implicated in the maintenance of nicotine addiction. However, it remains largely unclear about the white matter (WM) microstructural alterations of insula in nicotine addiction and whether the WM alterations of insula could predict smoking cessation outcomes. In this study, 58 male nicotine-dependent smokers and 34 matched male nonsmoking controls were recruited. After a 12-week smoking cessation treatment with varenicline, 38 smokers relapsed, and 20 did not relapse. Diffusion tensor imaging and probabilistic tractography were used to investigate the differences of WM tracts of insula between smokers and nonsmokers. Relative to nonsmokers, in the left hemisphere, smokers showed lower fractional anisotropy (FA) in the fiber tracts of anterior insula cortex-to-nucleus accumbens and posterior insula cortex-to-nucleus accumbens; in the right hemisphere, smokers showed higher FA, and lower axial diffusivity (AD), radial diffusivity (RD), and mean diffusivity (MD) in the fiber tracts of anterior insula cortex-to-medial orbitofrontal cortex, posterior insula cortex-to-medial orbitofrontal cortex, and posterior insula cortex-to-nucleus accumbens. However, there were no differences of WM diffusion properties between relapsers and nonrelapsers. This study is the first using probabilistic tractography to exclusively clarify the precise roles of insular WM tracts in smokers, which may provide new insights into the underlying neurobiology of nicotine addiction.

An Illustrated Guide to the Imaging Evolution of COVID in Non-Epidemic Areas of Southeast China.

Purpose: By analyzing the CT manifestations and evolution of COVID in non-epidemic areas of southeast China, analyzing the developmental abnormalities and accompanying signs in the early and late stages of the disease, providing imaging evidence for clinical diagnosis and identification, and assisting in judging disease progression and monitoring prognosis. Methods: This retrospective and multicenter study included 1,648 chest CT examinations from 693 patients with laboratory-confirmed COVID-19 infection from 16 hospitals of southeast China between January 19 and March 27, 2020. Six trained radiologists analyzed and recorded the distribution and location of the lesions in the CT images of these patients. The accompanying signs include crazy-paving sign, bronchial wall thickening, microvascular thickening, bronchogram sign, fibrous lesions, halo and reverse-halo signs, nodules, atelectasis, and pleural effusion, and at the same time, they analyze the evolution of the abovementioned manifestations over time. Result: There were 1,500 positive findings in 1,648 CT examinations of 693 patients; the average age of the patients was 46 years, including 13 children; the proportion of women was 49%. Early CT manifestations are single or multiple nodular, patchy, or flaky ground-glass-like density shadows. The frequency of occurrence of ground-glass shadows (47.27%), fibrous lesions (42.60%), and microvascular thickening (40.60%) was significantly higher than that of other signs. Ground-glass shadows increase and expand 3-7 days after the onset of symptoms. The distribution and location of lesions were not significantly related to the appearance time. Ground-glass shadow is the most common lesion, with an average absorption time of 6.2 days, followed by consolidation, with an absorption time of about 6.3 days. It takes about 8 days for pure ground-glass lesions to absorb. Consolidation change into ground glass or pure ground glass takes 10-14 days. For ground-glass opacity to evolve into pure ground-glass lesions, it takes an average of 17 days. For ground-glass lesions to evolve into consolidation, it takes 7 days, pure ground-glass lesions need 8 days to evolve into ground-glass lesions. The average time for CT signs to improve is 10-15 days, and the first to improve is the crazy-paving sign and nodules; while the progression of the disease is 6-12 days, the earliest signs of progression are air bronchogram signs, bronchial wall thickening, and bronchiectasis. There is no severe patient in this study. Conclusion: This study depicts the CT manifestation and evolution of COVID in non-epidemic origin areas, and provides valuable first-hand information for clinical diagnosis and judgment of patient's disease evolution and prediction.

Increased thalamic volume and decreased thalamo-precuneus functional connectivity are associated with smoking relapse.

The thalamus, with the highest density of nicotinic acetylcholine receptor (nAChR) in the brain, plays a central role in thalamo-cortical circuits that are implicated in nicotine addiction. However, little is known about whether the thalamo-cortical circuits are potentially predictive of smoking relapse. In the current study, a total of 125 participants (84 treatment-seeking male smokers and 41 age-matched male nonsmokers) were recruited. Structural and functional magnetic resonance images (MRI) were acquired from all participants. After a 12-week smoking cessation treatment with varenicline, the smokers were then divided into relapsers (n = 54) and nonrelapsers (n = 30). Then, we compared thalamic volume and seed-based thalamo-cortical resting state functional connectivity (rsFC) prior to the cessation treatment among relapsers, nonrelapsers and nonsmokers to investigate the associations between thalamic structure/function and smoking relapse. Increased thalamic volume was detected in smokers relative to nonsmokers, and in relapsers relative to nonrelapsers, especially on the left side. Moreover, decreased left thalamo-precuneus rsFC was detected in relapsers relative to nonrelapsers. Additionally, a logistic regression analysis showed that the thalamic volume and thalamo-precuneus rsFC predicted smoking relapse with an accuracy of 75.7%. These novel findings indicate that increased thalamic volume and decreased thalamo-precuneus rsFC are associated with smoking relapse, and these thalamic measures may be used to predict treatment efficacy of nicotine addiction and serve as a potential biomarker for personalized medicine.

Initial chest CT findings in COVID-19: correlation with clinical features.

In December 2019, coronavirus disease 2019 (COVID-19), a new de novo infectious disease, was first identified in Wuhan, China and quickly spread across China and around the world. The etiology was a novel betacoronavirus, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (Lu et al., 2020). On Mar. 11, 2020, World Health Organization (WHO) characterized COVID-19 as a global pandemic. As of Mar. 22, 2020, over 292 000 confirmed COVID-19 cases have been reported globally. To date, COVID-19, with its high infectivity, has killed more people than severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) combined (Wu and McGoogan, 2020).

Increased interregional functional connectivity of anterior insula is associated with improved smoking cessation outcome.

Damage to the insular cortex has been shown to disrupt smoking behavior. However, whether smoking cessation outcomes are associated with abnormal functions of insula and its subregions remains unclear. In this study, we investigated the relationship between insular functions (interregional functional connectivity and regional activity) and treatment outcomes of cigarette smoking. Thirty treatment-seeking smokers were recruited into the treatment study and underwent magnetic resonance imaging (MRI) scans immediately before and after the treatment. Sixteen participants remained abstinent from smoking (quitters), while 14 relapsed to smoking (relapers). Changes in resting-state functional connectivity and fractional amplitude of low frequency fluctuation (fALFF) across groups and visits were assessed using repeated measures ANCOVA. Significant interaction effects were detected: 1) between the left anterior insula and left precuneus; and 2) between the right anterior insula and left precuneus and medial frontal gyrus. Post-hoc region-of-interest analyses in brain areas showing interaction effects indicated significantly increased functional connectivity after treatment compared with before treatment in quitters but opposite longitudinal changes in relapsers. However, no significant effects in fALFF were observed. These novel findings suggest that increased interregional functional connectivity of the anterior insula is associated with improved smoking cessation outcome: individuals with increased functional connectivity of the anterior insula during the treatment would more likely quit smoking successfully. These insular circuits may serve as therapeutic targets for more efficacious treatment of nicotine addiction.

Temporal changes of COVID-19 pneumonia by mass evaluation using CT: a retrospective multi-center study.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has widely spread worldwide and caused a pandemic. Chest CT has been found to play an important role in the diagnosis and management of COVID-19. However, quantitatively assessing temporal changes of COVID-19 pneumonia over time using CT has still not been fully elucidated. The purpose of this study was to perform a longitudinal study to quantitatively assess temporal changes of COVID-19 pneumonia. METHODS: This retrospective and multi-center study included patients with laboratory-confirmed COVID-19 infection from 16 hospitals between January 19 and March 27, 2020. Mass was used as an approach to quantitatively measure dynamic changes of pulmonary involvement in patients with COVID-19. Artificial intelligence (AI) was employed as image segmentation and analysis tool for calculating the mass of pulmonary involvement. RESULTS: A total of 581 confirmed patients with 1,309 chest CT examinations were included in this study. The median age was 46 years (IQR, 35-55; range, 4-87 years), and 311 (53.5%) patients were male. The mass of pulmonary involvement peaked on day 10 after the onset of initial symptoms. Furthermore, the mass of pulmonary involvement of older patients (>45 years) was significantly severer (P<0.001) and peaked later (day 11 vs. day 8) than that of younger patients (≤45 years). In addition, there were no significant differences in the peak time (day 10 vs. day 10) and median mass (P=0.679) of pulmonary involvement between male and female. CONCLUSIONS: Pulmonary involvement peaked on day 10 after the onset of initial symptoms in patients with COVID-19. Further, pulmonary involvement of older patients was severer and peaked later than that of younger patients. These findings suggest that AI-based quantitative mass evaluation of COVID-19 pneumonia hold great potential for monitoring the disease progression.

Brain Gray Matter Volume and Functional Connectivity Are Associated With Smoking Cessation Outcomes.

Smoking cessation is critical for reducing the risk of respiratory, cardiovascular diseases and cancers. However, most cessation attempts resulted in failure. In the present study, we aim to explore whether alterations of brain gray matter (GM) volume and functional connectivity (FC) are related to cessation outcomes, in hope of providing evidence for improving smoking cessation outcomes. Seventy-three smokers and 41 non-smokers were enrolled in the present study. All smokers participated in a 12-week smoking cessation treatment during which Varenicline was used to aid cessation. At the end of treatment, the smokers were divided into quitters and relapsers based on their abstinence performance. Structural magnetic resonance imaging (MRI) and voxel-based morphometry were applied to quantify the differences of regional brain volumes among the three groups at baseline. In addition, resting-state FC was used to investigate the related functional changes. In comparison with non-smokers, the smokers showed smaller GM volume in the left dorsal medial thalamus. Among the 73 smokers, 29 subjects successfully quitted smoking. The quitters showed greater GM volume than the relapsers in the right postcentral gyrus, right putamen\caudate nucleus and left orbitofrontal cortex (OFC). The GM volume in the left OFC was found to be negatively correlated with the pack years and daily smoking amount in the quitters. Furthermore, we found significantly reduced FC between left thalamus and left cerebellum in the relapsers. These findings extended our knowledge of the neural mechanism of smoking cessation, and suggested that brain structural and functional changes were related to smoking cessation outcomes.

Different patterns of gray matter density in early- and middle-late-onset Parkinson's disease: a voxel-based morphometry study.

Early-onset Parkinson's disease (EOPD) has a clinical course and characteristics distinct from middle-late-onset Parkinson's disease (M-LOPD). Although many studies have investigated these differences, the neural mechanisms of these characteristics remain unclear. This study aimed to investigate the morphological differences, and their related clinical significance, between EOPD and M-LOPD patients. We recruited two groups of patients, 28 EOPD patients and 37 M-LOPD patients, and two age- and sex-matched control groups (23 controls in each group). The voxel-based morphometry (VBM) technique was used to examine changes in gray matter (GM) density between patients and their corresponding controls. Compared with controls, EOPD patients had lower GM density in the left putamen, inferior frontal gyrus and insula, and higher GM density in the right occipital lobe and bilateral cerebellum posterior lobes. M-LOPD patients had lower GM density in the left cerebellum posterior lobe, occipital lobe and right supplementary motor area (SMA), and higher GM density in the left middle temporal gyrus. Correlation analyses showed that GM density values in the right cerebellum posterior lobe positively correlated with the Unified Parkinson's Disease Rating Scale (UPDRS) motor scores and the Hoehn-Yahr stages in EOPD patients. Our results reveal different patterns of structural changes in EOPD and M-LOPD patients. A probable compensatory effect of the cerebellum was observed and may partly explain the slower decline of motor function in EOPD patients.