Abnormal large-scale resting-state functional networks in anti-N-methyl-D-aspartate receptor encephalitis

BackgroundPatients with anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis often experience severe symptoms. Resting-state functional MRI (rs-fMRI) has revealed widespread impairment of functional networks in patients. However, the changes in information flow remain unclear. This study aims to investigate the intrinsic functional connectivity (FC) both within and between resting-state networks (RSNs), as well as the alterations in effective connectivity (EC) between these networks.MethodsResting-state functional MRI (rs-fMRI) data were collected from 25 patients with anti-NMDAR encephalitis and 30 healthy controls (HCs) matched for age, sex, and educational level. Changes in the intrinsic functional connectivity (FC) within and between RSNs were analyzed using independent component analysis (ICA). The functional interaction between RSNs was identified by granger causality analysis (GCA).ResultsCompared to HCs, patients with anti-NMDAR encephalitis exhibited lower performance on the Wisconsin Card Sorting Test (WCST), both in terms of correct numbers and correct categories. Additionally, these patients demonstrated decreased scores on the Montreal Cognitive Assessment (MoCA). Neuroimaging studies revealed abnormal intra-FC within the default mode network (DMN), increased intra-FC within the visual network (VN) and dorsal attention network (DAN), as well as increased inter-FC between VN and the frontoparietal network (FPN). Furthermore, aberrant effective connectivity (EC) was observed among the DMN, DAN, FPN, VN, and somatomotor network (SMN).ConclusionPatients with anti-NMDAR encephalitis displayed noticeable deficits in both memory and executive function. Notably, these patients exhibited widespread impairments in intra-FC, inter-FC, and EC. These results may help to explain the pathophysiological mechanism of anti-NMDAR encephalitis

Autoimmune nodopathy with anti-contactin 1 antibody characterized by cerebellar dysarthria: a case report and literature review

BackgroundAutoimmune nodopathy (AN) has emerged as a novel diagnostic category that is pathologically different from classic chronic inflammatory demyelinating polyneuropathy. Clinical manifestations of AN include sensory or motor neuropathies, sensory ataxia, tremor, and cranial nerve involvement. AN with a serum-positive contactin-1 (CNTN1) antibody usually results in peripheral nerve demyelination. In this study, we reported a rare case of AN with CNTN1 antibodies characterized by the presence of CNTN1 antibodies in both serum and cerebrospinal fluid, which is associated with cerebellar dysarthria.MethodsA 25-year-old man was admitted to our hospital due to progressive dysarthria with limb tremors. The patient was initially diagnosed with peripheral neuropathy at a local hospital. Three years after onset, he was admitted to our hospital due to dysarthria, apparent limb tremor, and limb weakness. At that time, he was diagnosed with spinocerebellar ataxia. Eight years post-onset, during his second admission, his condition had notably deteriorated. His dysarthria had evolved to typical distinctive cerebellar characteristics, such as tremor, loud voice, stress, and interrupted articulation. Additionally, he experienced further progression in limb weakness and developed muscle atrophy in the distal limbs. Magnetic resonance imaging (MRI), nerve conduction studies (NCS), and autoimmune antibody tests were performed.ResultsThe results of the NCS suggested severe demyelination and even axonal damage to the peripheral nerves. MRI scans revealed diffuse thickening of bilateral cervical nerve roots, lumbosacral nerve roots, cauda equina nerve, and multiple intercostal nerve root sheath cysts. Furthermore, anti-CNTN1 antibody titers were 1:10 in the cerebrospinal fluid (CSF) and 1:100 in the serum. After one round of rituximab treatment, the patient showed significant improvement in limb weakness and dysarthria, and the CSF antibodies turned negative.ConclusionApart from peripheral neuropathies, cerebellar dysarthria (central nervous system involvement) should not be ignored in AN patients with CNTN1 antibodies

Annual mapping of <i>Spartina alterniflora</i> with deep learning and spectral-phenological features from 2017 to 2021 in the mainland of China

Spartina alterniflora (S. alterniflora) expanded continuously in the coastal zone of the mainland in China, which caused serious ecological problems. Currently, there are several studies on large-scale time-series mappings of S. alterniflora but the time interval of these mappings is over three years. Consequently, these studies fail to capture the rapid dynamics of S. alterniflora. Leveraging the temporal transferability of DeepLabv3+, this study annotated 2020 Sentinel-2 data as training data to obtain the optimal model. Subsequently, we applied this model to predict Sentinel-2 data for other years (2017, 2018, 2019 and 2021), respectively. Ultimately, we produced accurate time-series maps of S. alterniflora from 2017 to 2021 in mainland China (China mainland S. alterniflora, CMSA). Meanwhile, it also confirmed the high transferability of the DeepLabv3+ model in the time-series mapping of S. alterniflora. The obtained annual time-series maps have revealed a more detailed account of how S. alterniflora changes over time that previous studies had failed to capture. It has enriched our understanding of the dynamic changes in S. alterniflora. The mapping results revealed that S. alterniflora continued to grow along the mainland coast from 2017 to 2021 but at a slower growth rate. In some local regions, we discovered: (1) S. alterniflora populations can naturally shrink under certain conditions, such as in the Dandou Sea; (2) the area of S. alterniflora has increased slightly after decreasing for several years (e.g. Yueqing Bay). However, in some other regions, there is no observed regrowth after removal (e.g. Dongtan on Chongming Island and Chuandong Port).</p