In vivo Hyperpolarized Metabolic Imaging to Monitor the Progression of Hepatitis B Virus (HBV)-Related Hepatitis to Liver Fibrosis.

PURPOSE: This study aimed to assess metabolic changes to monitor the progression from normal liver to hepatitis B virus (HBV)-related hepatitis and liver fibrosis using hyperpolarized 13C magnetic resonance imaging (MRI). PROCEDURES: Hepatitis was induced in mice (n = 16) via hydrodynamic injection of HBV 1.2 plasmid (25 µg). Among them, liver fibrosis was induced in the mice (n = 8) through weight-adapted administration of thioacetamide with ethanol. Normal control mice (n = 8) were injected with a phosphate buffer solution. Subsequently, a hyperpolarized 13C MRI was performed on the mouse liver in vivo. The level of hepatitis B surface antigen (HBsAg) in blood serum was measured. Statistical analysis involved comparing the differential metabolite ratios, blood biochemistry values, and body weight among the three groups using the Kruskal-Wallis one-way analysis of variance. RESULTS: HBsAg was absent in the normal and fibrosis groups, while it was detected in the hepatitis group. The ratios of [1-13C] lactate/pyruvate, [1-13C] alanine/pyruvate, [1-13C] lactate/total carbon, and [1-13C] alanine/total carbon were significantly lower in the normal control group than in the hepatitis and fibrosis groups (p < 0.05). Moreover, these ratios were significantly higher in the fibrosis group than in the hepatitis group (p < 0.05). However, no significant differences were observed in either [1-13C] pyruvate-hydrate/pyruvate or [1-13C] pyruvate-hydrate/total carbon among the three groups. CONCLUSIONS: The levels of [1-13C] lactate and [1-13C] alanine in vivo may serve as valuable indicators for differentiating between HBV-related hepatitis, liver fibrosis, and normal liver.

Altered Sexual Response-Related Functional Connectivity and Morphometric Changes Influenced by Sex Hormones across Menopausal Status.

Our study retrospectively investigated differential patterns of the functional connectivity (FC) of core brain regions synchronous with morphometric changes associated with sexual dysfunction in menopausal women, and their correlations with sexual hormones. Twenty-three premenopausal women (mean age: 41.52 ± 7.38 years) and 21 menopausal women (mean age: 55.52 ± 2.80 years) underwent sex hormone level measurements with high-resolution T1 and functional magnetic resonance imaging (MRI) during rest, neutral, and sexual arousal conditions. Analysis of covariance adjusted for age was used to compare the FC and gray matter (GM) volume between the two groups. Menopausal women showed lower GM volumes in the superior frontal gyrus (SFG), superior temporal pole, parahippocampal gyrus (PHG), hippocampus (Hip), amygdala (Amg), and cerebellum (Cb) compared to premenopausal women (p < 0.05). In addition, compared to premenopausal women, menopausal women showed decreased FC of seed regions involved in the SFG, frontal eye fields, and Amg, as well as target regions involved in the PHG, Hip, inferior frontal gyrus, Cb, and vermis (p < 0.005). Furthermore, the FC between the right Amg and right Cb and between the left Amg and right Cb during sexual arousal in both groups was positively correlated with total estrogen and estradiol levels, respectively (p < 0.01). The GM volume values in the right Amg and right Cb were positively correlated with total estrogen and estradiol levels (p < 0.05). Our study demonstrated an association between menopause-related differential FC and GM volume variations and fluctuating sex hormones. Our findings highlight that overlapping brain regions with functional alterations and morphometric changes are closely linked with menopausal symptom-related decreases in sexual arousal and hormone levels.

Neural Correlates of Emotion-Cognition Interaction During Working Memory Maintenance in Obsessive-Compulsive Disorder: The Role of the Dorsolateral Prefrontal Cortex.

The neural correlates for the effect of emotional distraction on working memory (WM) function in obsessive-compulsive disorder (OCD) have not been clearly identified. This study utilized functional magnetic resonance imaging (fMRI) to investigate the effect of emotional distraction during WM maintenance in OCD patients and to determine if the frontoparietal region was involved during the task. Patients with OCD tried to maintain WM during the task-irrelevant anxiety-provoking distractions, which induced interruption and needed attention. Compared with healthy controls, the patients with OCD showed significantly increased activities in the dorsolateral prefrontal cortex (DLPFC) supplementary motor area during the delayed-response WM task with anxiety-provoking distractors. An increase in the activity of the DLPFC and SMA reflects compensatory efforts of neural circuits to perform cognitive tasks by controlling emotions and inhibiting the interference of anxiety provoking distractors during WM tasks. In addition, the brain areas showed significantly decreased activities during the delayed-response WM task with neutral distractors were superior parietal gyrus and fusiform gyrus. The parietal cortex, along with the DLPFC is the main structure for frontoparietal network and is involved in cognitive control. Therefore, parietal dysfunction in OCD patients prevents them from paying appropriate attention to visual processing for picture distractors during the WM task. Our findings might be helpful for further understanding of the neural correlates that are associated with the effects of emotional distraction on cognitive function in OCD.