Characterization of local white matter microstructural alterations in Alzheimer's disease: A reproducible study.

Alzheimer's disease (AD) is a neurodegenerative disease with a close association with microstructural alterations in white matter (WM). Current studies lack the characterization and further validation of specific regions in WM fiber tracts in AD. This study subdivided fiber tracts into multiple fiber clusters on the basis of automated fiber clustering and performed quantitative analysis along the fiber clusters to identify local WM microstructural alterations in AD. Diffusion tensor imaging data from a public dataset (53 patients with AD and 70 healthy controls [HCs]) and a clinical dataset (27 patients with AD and 19 HCs) were included for mutual validation. Whole-brain tractograms were automatically subdivided into 800 clusters through the automatic fiber clustering approach. Then, 100 segments were divided along the clusters, and the diffusion properties of each segment were calculated. Results showed that patients with AD had significantly lower fraction anisotropy (FA) and significantly higher mean diffusivity (MD) in some regions of the fiber clusters in the cingulum bundle, uncinate fasciculus, external capsule, and corpus callosum than HCs. Importantly, these changes were reproducible across the two datasets. Correlation analysis revealed a positive correlation between FA and Mini-Mental State Examination (MMSE) scores and a negative correlation between MD and MMSE in these clusters. The accuracy of the constructed classifier reached 89.76% with an area under the curve of 0.93. This finding indicates that this study can effectively identify local WM microstructural changes in AD and provides new insight into the analysis and diagnosis of WM abnormalities in patients with AD.

Preoperative diffusion tensor imaging: Fiber-trajectory-distribution-based tractography to identify facial nerve in vestibular schwannoma.

PURPOSE: Tractography of the facial nerve based on diffusion MRI is instrumental before surgery for the resection of vestibular schwannoma, but no excellent methods usable for the suppression of motion and image noise have been proposed. The aim of this study was to effectively suppress noise and provide accurate facial nerve reconstruction by extend a fiber trajectory distribution function based on the fourth-order streamline differential equations. METHODS: Preoperative MRI from 33 patients with vestibular schwannoma who underwent surgical resection were utilized in this study. First, T1WI and T2WI were used to obtain mask images and regions of interest. Second, probabilistic tractography was employed to obtain the fibers representing the approximate facial nerve pathway, and these fibers were subsequently translated into orientation information for each voxel. Last, the voxel orientation information and the peaks of the fiber orientation distribution were combined to generate a fiber trajectory distribution function, which was used to parameterize the anatomical information. The parameters were determined by minimizing the cost between the trajectory of fibers and the estimated directions. RESULTS: Qualitative and visual analyses were used to compare facial nerve reconstruction with intraoperative recordings. Compared with other methods (SD_Stream, iFOD1, iFOD2, unscented Kalman filter, parallel transport tractography), the fiber-trajectory-distribution-based tractography provided the most accurate facial nerve reconstructions. CONCLUSION: The fiber-trajectory-distribution-based tractography can effectively suppress the effect of noise. It is a more valuable aid for surgeons before vestibular schwannoma resection, which may ultimately improve the postsurgical patient's outcome.

Investigation into white matter microstructure differences in visual training by using an automated fiber tract subclassification segmentation quantification method.

Visual training has emerged as a useful framework for investigating training-related brain plasticity, a highly complex task involving the interaction of visual orientation, attention, reasoning, and cognitive functions. However, the effects of long-term visual training on microstructural changes within white matter (WM) is poorly understood. Therefore, a set of visual training programs was designed, and automated fiber tract subclassification segmentation quantification based on diffusion magnetic resonance imaging was performed to obtain the anatomical changes in the brains of visual trainees. First, 40 healthy matched participants were randomly assigned to the training group or the control group. The training group underwent 10 consecutive weeks of visual training. Then, the fiber tracts of the subjects were automatically identified and further classified into fiber clusters to determine the differences between the two groups on a detailed scale. Next, each fiber cluster was divided into segments that can analyze specific areas of a fiber cluster. Lastly, the diffusion metrics of the two groups were comparatively analyzed to delineate the effects of visual training on WM microstructure. Our results showed that there were significant differences in the fiber clusters of the cingulate bundle, thalamus frontal, uncinate fasciculus, and corpus callosum between the training group compared and the control group. In addition, the training group exhibited lower mean fractional anisotropy, higher mean diffusivity and radial diffusivity than the control group. Therefore, the long-term cognitive activities, such as visual training, may systematically influence the WM properties of cognition, attention, memory, and processing speed.

GlideScope versus C-MAC D-blade videolaryngoscope for double-lumen tube intubation in patients with anticipated difficult airways: A multi-center, prospective, randomized, controlled trial.

STUDY OBJECTIVE: Videolaryngoscopes are widely used to visualize difficult airways. Our aim was to compare the GlideScope and C-MAC D-blade videolaryngoscopes for double-lumen tube (DLT) intubation in patients with difficult airways. DESIGN: A multi-center, prospective, randomized controlled trial. SETTING: Three comprehensive tertiary, high-volume hospitals from 5 December 2020 to 4 November 2021. PATIENTS: We included 348 adult patients with anticipated difficult airways who underwent elective thoracic surgery. INTERVENTIONS: Patients were randomized into two groups: GlideScope and C-MAC D-blade. Following anesthesia induction, DLT intubation was performed using different videolaryngoscopes. MEASUREMENTS: The primary outcome was the first-pass success rate of DLT intubation. All other results were recorded as secondary outcomes. MAIN RESULTS: No significant differences were observed in the first-pass success rate of DLT intubation between the GlideScope and C-MAC D-blade (86.21% and 89.66%, respectively; P = 0.323). However, compared with the GlideScope, the C-MAC D-blade provided a lower Cormack-Lehane grade (P < 0.001), lower rates of external laryngeal pressure (48 vs. 15, P < 0.001), and postprocedure sore throat (26 vs. 8, P < 0.001). The numerical rating score for difficulty of videolaryngoscope insertion into the oral cavity, delivery to the glottis, and intubation into the main bronchus were significantly lower when using the C-MAC D-blade (P < 0.001). Moreover, the duration of DLT intubation was shorter in the C-MAC D-blade group (81 s [70-97 s] vs. 95 s [78-115 s], P < 0.001). In each group, two patients underwent fiberoptic intubation after three attempts with a videolaryngoscope failed. CONCLUSIONS: In patients with difficult airways, the GlideScope and C-MAC D-blade provided a similar success rate on the first DLT intubation attempt; however, the C-MAC D-blade offers a better glottic view, easier and faster intubation, and lower incidence of sore throat.

CNTSeg: A multimodal deep-learning-based network for cranial nerves tract segmentation.

The segmentation of cranial nerves (CNs) tracts based on diffusion magnetic resonance imaging (dMRI) provides a valuable quantitative tool for the analysis of the morphology and course of individual CNs. Tractography-based approaches can describe and analyze the anatomical area of CNs by selecting the reference streamlines in combination with ROIs-based (regions-of-interests) or clustering-based. However, due to the slender structure of CNs and the complex anatomical environment, single-modality data based on dMRI cannot provide a complete and accurate description, resulting in low accuracy or even failure of current algorithms in performing individualized CNs segmentation. In this work, we propose a novel multimodal deep-learning-based multi-class network for automated cranial nerves tract segmentation without using tractography, ROI placement or clustering, called CNTSeg. Specifically, we introduced T1w images, fractional anisotropy (FA) images, and fiber orientation distribution function (fODF) peaks into the training data set, and design the back-end fusion module which uses the complementary information of the interphase feature fusion to improve the segmentation performance. CNTSeg has achieved the segmentation of 5 pairs of CNs (i.e. optic nerve CN II, oculomotor nerve CN III, trigeminal nerve CN V, and facial-vestibulocochlear nerve CN VII/VIII). Extensive comparisons and ablation experiments show promising results and are anatomically convincing even for difficult tracts. The code will be openly available at https://github.com/IPIS-XieLei/CNTSeg.

Study on the Evaluation of Lung Cancer Patients from the Three Aspects of Emotion.

In recent years, epidemiological survey data have shown that lung cancer is the tumor with the fastest increase in cancer incidence and mortality in China. The incidence and mortality of lung cancer in China rank first among tumors, and 80% of patients die within one year of diagnosis. This paper aims to study the evaluation of lung cancer patients from three aspects of emotion, coping style, and Quality of Life (QoL), expounding on the changes in emotion, coping style, and QoL in lung cancer patients after chemotherapy. We assess the negative emotions and survival of lung cancer patients after chemotherapy quality satisfaction survey research. We investigate the general data, QoL, and coping styles of 219 lung cancer patients undergoing chemotherapy before, during, and after chemotherapy based on the artificial intelligence processor. All survey data are input into SPSS 19 for descriptive and relevant statistical analysis. The experimental results show that under a survey of 219 lung cancer chemotherapy patients with negative emotions and QoL satisfaction after chemotherapy, at a significance level of = 0.05, there is a linear regression relationship between mental resilience and anxiety and depression.

Mapping brain-wide excitatory projectome of primate prefrontal cortex at submicron resolution and comparison with diffusion tractography.

Resolving trajectories of axonal pathways in the primate prefrontal cortex remains crucial to gain insights into higher-order processes of cognition and emotion, which requires a comprehensive map of axonal projections linking demarcated subdivisions of prefrontal cortex and the rest of brain. Here, we report a mesoscale excitatory projectome issued from the ventrolateral prefrontal cortex (vlPFC) to the entire macaque brain by using viral-based genetic axonal tracing in tandem with high-throughput serial two-photon tomography, which demonstrated prominent monosynaptic projections to other prefrontal areas, temporal, limbic, and subcortical areas, relatively weak projections to parietal and insular regions but no projections directly to the occipital lobe. In a common 3D space, we quantitatively validated an atlas of diffusion tractography-derived vlPFC connections with correlative green fluorescent protein-labeled axonal tracing, and observed generally good agreement except a major difference in the posterior projections of inferior fronto-occipital fasciculus. These findings raise an intriguing question as to how neural information passes along long-range association fiber bundles in macaque brains, and call for the caution of using diffusion tractography to map the wiring diagram of brain circuits.

In the brain is a web of interconnected nerve cells that send messages to one another via spindly projections called axons. These axons join together at junctions called synapses to create circuits of nerve cells which connect neighboring or distant brain regions. Notably, long-range neural connections underpin higher-order cognitive skills (such as planning and emotion regulation) which make humans distinct from our primate relatives. Only by untangling these far-reaching networks can researchers begin to delineate what sets the human brain apart from other species. Researchers deploy a range of imaging techniques to map neural networks: scanning entire brains using MRI machines, or imaging thin slices of fluorescently labelled brain tissue using powerful microscopes. However, tracing long-range axons at a high resolution is challenging, and has stirred up debate about whether some neural tracts, such as the inferior fronto-occipital fasciculus, are present in all primates or only humans. To address these discrepancies, Yan, Yu et al. employed a two-pronged approach to map neural circuits in the brains of macaques. First, two techniques ­ called viral tracing and two-photon microscopy ­ were used to create a three-dimensional, fine-grain map showing how the ventrolateral prefrontal cortex (vlPFC), which regulates complex behaviors, connects to the rest of the brain. This revealed prominent axons from the vlPFC projecting via a single synapse to distant brain regions involved in higher-order functions, such as encoding memories and processing emotion. However, there were no direct, monosynaptic connections between the vlPFC and the occipital lobe, the brain's visual processing center at the back of the head. Next, Yan, Yu et al. used a specialized MRI scanner to create an atlas of neural circuits connected to the vlPFC, and compared these results to a technique tracing axons stained with a fluorescent dye. In general, there was good agreement between the two methods, except for major differences in the rear-end projections that typically form the inferior fronto-occipital fasciculus. This suggests that this long-range neural pathway exists in monkeys, but it connects via multiple synapses instead of a single junction as was previously thought. The findings of Yan, Yu et al. provide new insights on the far-reaching neural pathways connecting distant parts of the macaque brain. It also suggests that atlases of neural circuits from whole brain scans should be taken with caution and validated using neural tracing experiments.

Three new flavonoid glycosides from Smilax glabra and their anti-inflammatory activity.

Three new flavonoid glycosides, 2(S)-5-hydroxy-6,8-dimethoxyflavonone-7-O-ß-D-glucopyranosyl-(1→6)-O-ß-D-glucopyranoside (1), 5-hydroxy-3,8-dimethoxyflavone-7-O-ß-D-glucopyranosyl-(1→6)-O-ß-D-glucopyranoside (2) and 3,7-dihydroxy-8-methoxyflavone-6-O-ß-D-glucopyranosyl-(1→6)-O-ß-D-glucopyranoside (3), together with five known flavonoids (4-8) were isolated from the roots of Smilax glabra Roxb. Their structures were elucidated on the basis of chemical and spectral evidence, as well as by comparison with literature data. Three new flavonoids were subjected to evaluate anti-inflammatory activity. Compounds 1-3 inhibited the NF κB induction by 32.2, 55.8 and 61.7%, respectively.

Six new furostanol glycosides from Smilax glauco-china and their cytotoxic activity.

Six new steroidal saponins, namely glauco-chinaosides A-F, and one known compound were isolated from the tubers of Smilax glauco-china. Their structures were elucidated by a combination of spectroscopic analysis and hydrolysis followed by spectral and chromatographic analysis. Compounds 1-7 were tested in vitro for their cytotoxic activities against four human tumor cell lines (SH-SY5Y, SGC-7901, HCT-116, and Lovo). Compounds 1, 2, and 5 exhibited cytotoxic activity against SGC-7901, with IC50 values of 2.7, 11.5, and 6.8 µM, respectively.

[Phenylpropanoid Constituents of Smilax trinervula].

Objective: To study the phenylpropanoid constituents of Smilax trinervula. Methods: The chemical constituents were isolated and purified by macroporous adsorption resin chromatography, gel chromatography and high performance liquid chromatography. Their structures were identified by spectroscopic analysis and comparison with literatures. Results: Nine phenylpropanoid compounds were isolated and their structures were identified as( +)-lyoniresin-4-yl ß-D-glucopyranoside( 1),(-)-8'-epilyoniresin-4-yl ß-glucopyranoside( 2),( +)-lyoniresin-4'-yl ß-glucopyranoside( 3),(-)-lyoniresinol-2α-O-ß-D-glucopyranoside( 4),( +)-lyoniresinol( 5),icariol A2( 6),icariol A2-4-O-ß-D-glucopyranoside( 7),7S,7'S,8R,8'R-icariol A2-9-O-ß-D-glucopyranoside( 8) and( +)-syringaresinol-4'-O-ß-D-glucopyranoside( 9). Conclusion: All the compounds are isolated from Smilax genus for the first time.

Research progress of bioactivity of steroidal saponins in recent ten years.

Steroidal saponins have a wide range of pharmacological effects and biological activities, such as anti-tumor, antifungal, hypoglycemic, immune regulation, insecticides, etc. In the last ten years, some new structures of steroidal saponins compounds were found from natural plants, they have some new and different activities. In order to accelerate the research on the drug innovation of steroidal saponins, we summarized the new progress of the research on such compounds.