Changes in the blood-nerve barrier after sciatic nerve cold injury:indications supporting early treatment

Severe edema in the endoneurium can occur after non-freezing cold injury to the peripheral nerve, which suggests damage to the blood-nerve barrier. To determine the effects of cold injury on the blood-nerve barrier, the sciatic nerve on one side of Wistar rats was treated with low tem- peratures （3-5℃） for 2 hours. The contralateral sciatic nerve was used as a control. We assessed changes in the nerves using Evans blue as a fluid tracer and morphological methods. Excess fluid was found in the endoneurium 1 day after cold injury, though the tight junctions between cells remained closed. From 3 to 5 days after the cold injury, the fluid was still present, but the tight junctions were open. Less tracer leakage was found from 3 to 5 days after the cold injury compared with 1 day after injury. The cold injury resulted in a breakdown of the blood-nerve barrier func- tion, which caused endoneurial edema. However, during the early period, the breakdown of the blood-nerve barrier did not include the opening of tight junctions, but was due to other factors. Excessive fluid volume produced a large increase in the endoneurial fluid pressure, prevented liquid penetration into the endoneurium from the microvasculature. These results suggest that drug treatment to patients with cold injuries should be administered during the early period after injury because it may be more difficult for the drug to reach the injury site through the microcirculation after the tissue fluid pressure becomes elevated.

Alzheimer’s disease early diagnostic and staging biomarkers revealed by large-scale cerebrospinal fluid and serum proteomic profiling

Amyloid-b,tau pathology,and biomarkers of neurodegeneration make up the core diagnostic biomarkers of Alzheimer disease(AD).However,these proteins represent only a fraction of the complex biological processes underlying AD,and individuals with other brain diseases in which AD pathology is a comorbidity also test positive for these diagnostic biomarkers.More ADspecific early diagnostic and disease staging biomarkers are needed.In this study,we performed tandem mass tag proteomic analysis of paired cerebrospinal fluid(CSF)and serum samples in a discovery cohort comprising 98 participants.Candidate biomarkers were validated by parallel reaction monitoring–based targeted proteomic assays in an independent multicenter cohort comprising 288 participants.We quantified 3,238 CSF and 1,702 serum proteins in the discovery cohort,identifying 171 and 860 CSF proteins and 37 and 323 serum proteins as potential early diagnostic and staging biomarkers,respectively.In the validation cohort,58 and 21 CSF proteins,as well as 12 and 18 serum proteins,were verified as early diagnostic and staging biomarkers,respectively.Separate 19-protein CSF and an 8-protein serum biomarker panels were built by machine learning to accurately classify mild cognitive impairment(MCI)due to AD from normal cognition with areas under the curve of 0.984 and 0.881,respectively.The 19-protein CSF biomarker panel also effectively discriminated patients with MCI due to AD from patients with other neurodegenerative diseases.Moreover,we identified 21 CSF and 18 serum stage-associated proteins re-flecting AD stages.Our findings provide a foundation for developing bloodbased tests for AD screening and staging in clinical practice.

Dysfunctional autophagy in Alzheimer's disease: pathogenic roles and therapeutic implications

Neuronal autophagy is essential for neuronal survival and the maintenance of neuronal homeostasis. Increasing evidence has implicated autophagic dysfunction in the pathogenesis of Alzheimer＇s disease （AD）. The mechanisms underlying autophagic failure in AD involve several steps, from autophagosome formation to degradation. The effect of modulating autophagy is context-dependent. Stimulation of autophagy is not always beneficial. During the implementation of therapies that modulate autophagy, the nature of the autophagic defect, the timing of intervention, and the optimal level and duration of modulation should be fully considered.

Manic-depressive Psychosis as the Initial Symptom in Adult Siblings with Late-onset Combined Methylmalonic Aciduria and Homocystinemia, Cobalamin C Type

Methylmalonic aciduria （MMA） is an autosomal recessive disorder of cobalamin （cbl） metabolism. Cobalamin C （cblC） disease is the most common type of MMA and is characteristically concurrent with homocystinemia （HCY） due to impaired synthesis of two active forms of cbl, namely adenosylcobalamin （AdoCbl） and methylcobalamin （MeCbl）. The estimated worldwide incidence of MMA ranges between 1：48,000 and 1：250,000. Mutations of the MMA and HCY type C protein （MMACtfC） gene are responsible for cblC disease and were first identified by Lerner-Ellis et aL in 2006.By the year 2016, more than 82 different MMACHC gene mutations have been reported （http：// www.hgmd.cf.ac.uk/ac/index.php）. Among these mutations, c.609G〉A （p.W203X） was reported to be the most frequent cblC mutation in Chinese patients.

Overlap between Headache, Depression, and Anxiety in General Neurological Clinics： A Cross-sectional Study

Background： Many studies have reported that depression and anxiety have bidirectional relationship with headache. However, few researches investigated the roles of depression or anxiety in patients with headache. We surveyed the prevalence of depression and anxiety as a complication or cause of headache among outpatients with a chief complaint of headache at neurology clinics in general hospitals. Additional risk factors for depression and anxiety were also analyzed. Methods： A cross-sectional study was conducted at 11 general neurological clinics. All consecutive patients with a chief complaint of headache were enrolled. Diagnoses of depression and anxiety were made using the Chinese version of the Mini International Neuropsychiatric Interview, and those for headache were made according to the International Classification of Headache Disorders, 2＇ld Edition. The headache impact test and an 11-point verbal rating scale were applied to assess headache severity and intensity. Logistic regression was used to analyze risk factors of patients with headache for depression or anxiety. Results： A total of 749 outpatients with headache were included. Among them, 148 （19.7%） were diagnosed with depression and 103 （13.7%） with anxiety. Further analysis showed that 114 （15.2%） patients complaining headache due to somatic symptoms of psychiatric disorders and 82 （10.9%） had a depression or anxiety comorbidity with headache. Most patients with depression or anxiety manifested mild to moderate headaches. Poor sleep and severe headache-related disabilities were predictors for either depression or anxiety. Conclusion： Clinicians must identify the etiology of headache and recognize the effects of depression or anxiety on headache to develop specific treatments.

Expert Consensus on Clinical Diagnostic Criteria for Fatal Familial Insomnia

INTRODUCTION Fatal familial insomnia （FFI） is a serious and rare prion disease, which was first reported by Lugaresi et al. in 1986.Early diagnosis of FFI might be important for early and sufficient counseling of patients and their relatives, also concerning the risk of inheritance, and potentially also for treatment studies. However, the diagnosis of FFI might be difficult because of the heterogeneity of clinical features, low sensitivity of diagnostic tests, and absence of family history. The aim of the present study was to develop a clinical scheme and diagnostic criteria for FFI based on our research and expert consensus.