Alzheimer’s disease is a progressive， fatal， and neurodegenerative disease， clinically characterized by gradually developed cognitive and memory function decline， language and visuospatial disorders， and other aspects. It remains incurable and irreversible to date. In clinical settings， Alzheimer’s disease usually faces the possibility of untimely diagnosis， causing difficulties in the early intervention of the disease. Thus， it is essential to improve diagnostic efficiency and help patients diagnose Alzheimer’s disease as early as possible. With the continuous development of artificial intelligence （AI） technology， its application in Alzheimer’s disease imaging diagnosis has shown great potential. Meanwhile， it is also accompanied by many ethical issues. By exploring the ethical challenges brought by AI in the research and application of Alzheimer’s disease imaging diagnosis， such as data security， interpretability， algorithmic discrimination， and disclosure of incidental findings， the paper proposed the corresponding countermeasures， with a view to providing certain ethical guidance for the AI application in medical imaging diagnosis， protecting the rights and interests of subjects/patients， and promoting the healthy development of technology.

OBJECTIVES: Neurodegenerative diseases are closely associated with myelin loss, and the proliferation and differentiation of oligodendrocyte precursor cells (OPCs) are crucial to remyelination. However, the regulatory mechanisms involved remain incompletely understood. This study aims to investigate how astrocytes (ASTs) regulate the secretion of chitinase-3-like protein 1 (CHI3L1) via connexin 47 (Cx47)-mediated exosome signaling, and its subsequent effect on OPC proliferation. METHODS: Primary cells were isolated from postnatal day 1 Sprague-Dawley (P1SD) rats to establish 3 culture conditions: OPCs alone (Group O), OPCs in direct contact with ASTs (Group C), and OPCs cultured with AST-conditioned medium (Group A). Cellular morphology and proliferation were assessed using optical microscopy, 5-ethynyl-2'- deoxyuridine (EdU) incorporation, and flow cytometry. RNA sequencing (RNA-Seq) and bioinformatics analysis (BA) were conducted to identify differentially expressed genes (DEGs) among groups. Protein expression and cell cycle distribution were analyzed by Western blotting (WB) and flow cytometry. Exosomes were isolated and purified via differential centrifugation, characterized by nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM), and CHI3L1 expression in exosomes was verified via WB. Cx47 was silenced using small interfering RNA (siRNA) to evaluate its effect on OPC proliferation and exosome secretion. Artificial exosomes were constructed by encapsulating CHI3L1 in single unilamellar vesicles (SUVs), whose structure and size were validated by NTA and TEM. Following Cx47 knockdown, artificial exosomes were added back, and OPC proliferation was assessed via flow cytometry and EdU assay. RESULTS: Direct co-cultured with ASTs (Group C) resulted in significantly enhanced OPC proliferation compared to the Group O and Group A (P<0.05). RNA-Seq and WB analyses revealed that ASTs promote OPC proliferation and exosome secretion enriched in CHI3L1 through Cx47. Cx47 knockdown by siRNA led to significant decreases in OPC proliferation and exosome release (P<0.05). The inhibitory effect of Cx47 silencing on OPC proliferation was partially reversed by supplementation with either isolated exosomes or exogenous CHI3L1. CONCLUSIONS This study reveals a novel mechanism by which ASTs regulate OPC proliferation: Through direct contact, ASTs enhance the secretion of CHI3L1-rich exosomes via Cx47, thereby converting intercellular contact signals into secretory signals that promote OPC proliferation. As a key exosomal molecule, CHI3L1 may play an important role in neural function and remyelination and warrants further investigation.
Animals ; Exosomes/metabolism* ; Cell Proliferation ; Rats, Sprague-Dawley ; Rats ; Connexins/genetics* ; Oligodendrocyte Precursor Cells/metabolism* ; Astrocytes/metabolism* ; Chitinase-3-Like Protein 1/metabolism* ; Cells, Cultured ; Cell Differentiation

Recently,increasing attention has been paid to the study of orthostatic hypotension.Othostatic hypotension is a common systemic multisystem disease,with many clinical symptoms such as dizziness,headache,and blurred vision,which have a great impact on the quality of life of patients.Othostatic hypotension is divided into initial upright hypotension,delayed blood pressure recovery,classical orthostatic hypotension and delayed orthostatic hypotension.This paper aims to explore the research progress and clinical application value of delayed othostatic hypotension,and provide some reference for clinical diagnosis and treatment.

This study used the Appraisal of Guidelines Research & Evaluation-Health Systems （AGREE-HS） to demonstratively compare 34 global coronavirus disease-2019 （COVID-19） health systems guidance documents （HSGs） and 6 World Health Organization （WHO） standard HSGs. The comparison involved topic， participants， methods， recommendations， and implementability， with the aim of exploring the characteristics of emergency HSGs. The results showed that the emergency HSGs had an overall average score of 49%， with topic having the highest score， recommendations having the second highest score， and participants having the lowest score. The standard HSGs had an overall average score of 79%， with high scores in all items. The emergency HSGs had lower scores in participants， methods， recommendations， and implementability than the standard HSGs （P<0.001）， while the COVID-19 emergency HSGs developed by the WHO had higher score in topic than the standard HSGs （P<0.05）. Compared with those released by countries， the COVID-19 emergency HSG developed by the WHO showed superiority in all items and overall scores （P=0.000 2）. This indicates that emergency HSGs， represented by the COVID-19 emergency HSG， place equal emphasis on topic and recommendations as standard HSGs but have low requirements in terms of expert participation， evidence support， and comprehensive consideration in the time- and resource-limited context. They have the characteristics of prominent topics， clear purposes， orientation to demand， keeping up with the latest evidence， flexible adjustment， and timeliness， emphasizing immediate implementation effects， weakening long-term effects， and focusing on comprehensive benefits. Additionally， developers， types， and report completeness are important influencing factors.

Since the concept of patient versions of guidelines （PVGs） was introduced into China， several PVGs have been published in China， but we found that there is a big difference between the concept of PVG at home and abroad， and the reason for this difference has not been reasonably explained， which has led to ambiguity and even misapplication of the PVG concept by guideline developers. By analyzing the background and purpose of PVGs， and the understanding of the PVG concept by domestic scholars， we proposed the term patient guidelines （PGs）. This refers to guidelines developed under the principles of evidence-based medicine， centered on health issues that concern patients， and based on the best available evidence， intended for patient use. Except for the general attribute of providing information or education， which is typical of common health education materials， PGs also provide recommendations and assist in decision-making， so PGs include both the patient versions of guidelines （PVG） as defined by the Guidelines International Network （GIN） and "patient-directed guidelines"， i.e. clinical practice guidelines resulting from the adaptation or reformulation of recommendations through clinical practice guidelines.

At present， the process and methodology of patient guidelines （PGs） development varies greatly and lacks systematic and standardised guidance. In addition to the interviews with PG developers， we have sorted out the relevant methodology for the adaptation and development of existing clinical practice guideline recommendations and facilitated expert deliberations to achieve a consensus， so as to finally put forward a proposal for guidance on the process and methodology for the development of PGs. The development of PGs can be divided into the preparation stage， the construction stage， and the completion stage in general， but the specific steps vary according to the different modes of development of PGs. The development process of Model 1 is basically the same as the patient version of the guideline development process provided by the International Guidelines Network， i.e.， team formation， screening of recommendations， guideline drafing， user testing and feedback， approval and dissemination. The developer should also first determine the need for and scope of translating the clinical practice guideline into a patient version during the preparation phase. Model 2 adds user experience and feedback to the conventional clinical practice guideline development process （forming a team， determining the scope of the PG， searching， evaluating and integrating evidence， forming recommendations， writing the guideline， and expert review）. Based on the different models， we sort out the process and methods of PG development and introduce the specific methods of PG development， including how to identify the clinical problem and how to form recommendations based on the existing clinical practice guidelines， with a view to providing reference for guideline developers and related researchers.

Objective:To study the effects of periodontitis on bone and tryptophan metabolism of gut microbiota in the context of estrogen deficiency.Methods:Thirty-two female C57BL6/J mice were randomly divided into four groups based on table of random numbers ( n=8 in each group): Sham group, in which mice were given sham surgery; Sham_Lig group, in which mice were given sham surgery and were induced to periodontitis by ligating the bilateral maxillary second molars with 5-0 silk threads at the fourth week; Ovx group, in which mice were given bilateral ovariectomy; Ovx_Lig group, in which mice were given bilateral ovariectomy and were induced to periodontitis at the fourth week. After 8 weeks of ligation, the mice of 4 groups were euthanized for collecting the samples of femur, tibia, mandible and skull. Those samples were scanned by micro-CT to measure the bone mineral density (BMD), bone volume versus total volume ratio (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th) and trabecular spacing (Tb.Sp). The cecum contents of 4 groups of mice were collected for gut microbiota 16S rRNA gene sequencing. The tryptophan and its metabolites in intestinal tracts were detected by liquid chromatography-mass spectrometry. Pearson correlation analysis was performed to analyze the correlation between the abundance of gut microbiota and the content of tryptophan and its metabolites. Results:Femur BMD [(82.23±3.97) mg/cm 3], BV/TV [(9.25±1.37)%] and Tb.Th [(70.95±5.70) μm] in Ovx_Lig group were significantly lower than Ovx group [(96.30±3.76) mg/cm 3 ( P=0.004); (14.45±1.55)% ( P=0.022) and (87.58±8.02) μm ( P<0.001), respectively]. The β-diversity analysis of gut microbiota based on Bray-Curtis distance showed that samples of Ovx_Lig group and Ovx group were obviously grouped. Linear discriminant analysis effect size (LEfSe) showed that Alistipes was the representative genus in Ovx_Lig group. The relative abundance of Alistipes in Ovx_Lig group [(0.42±0.14)%] were significantly higher than that in Ovx group [(0.17±0.05)%] ( t=4.45, P<0.001). Tryptophan metabolism analysis showed that the content of kynurenic acid [(531.12±158.60) ng/g] in Ovx_Lig group were significantly higher than that in Ovx group [(400.42±57.96) ng/g] ( t=2.19, P=0.046). And the content of indole-3-carbaldehyde [(383.37±144.06) ng/g] in Ovx_Lig group were significantly lower than Ovx group [(701.72±141.93) ng/g] ( t=4.45, P<0.001). Correlation analysis showed that relative abundance of Alistipes was positively correlated with kynurenic acid ( r=0.32, P=0.088), while negatively correlated with indole-3-carbaldehyde ( r=-0.32, P=0.088). Conclusions:Periodontitis can induce bone destruction of femur in estrogen-deficient mice, the mechanism of which may be related to Alistipes in gut and the tryptophan metabolites kynurenic acid and indole-3-carbaldehyde.

The irrational use of Chinese patent medicines （CPM） is becoming more and more prominent， which makes the demand for clinical practice guidelines of CPM gradually increase. In order to make domestic scholars understand the latest developments and existing problems of the CPM guidelines， and promote its development， this paper introduced the concept of CPM guidelines， summarized the characteristics of the two development modes， namely “taking CPM as the key” and “taking disease/syndrome as the key”， and analyzed the current methodological status of developing and reporting CPM guidelines. Based on the existed problems， three suggestions have been put forward to optimize the quality of CPM guidelines， which were clarifying the target users and scope of CPM guidelines， establishing an open and transparent mechanism of the personnel involvement and process steps， and formulating implementable and operable recommendations for the use of CPM.

This paper summarized the key points and methods in terms of the establishment of the guideline working group and the management of conflict of interests， trying to provide reference for the development of clinical practice guidelines for Chinese patent medicine （CPM）. The establishment of the working group is the first important step for developing CPM guidelines. Considering the characteristics of the clinical practice guidelines for CPM， this study suggests that the three key elements of ‘multidisciplinarity’， ‘clinical relevance’ and ‘geographical representativeness’ should be put focus on when forming the working group. The guideline advisory committee， clinical expert group， evidence systematic evaluation group， secretary group and the external review group should be established. All group members should clarify the conflict of interest， and the process and management method of the conflict of interest should be clearly reported.

The identification of clinical questions for clinical practice guidelines of Chinese patent medicine （CPM） is important for subsequent evidence retrieval， evaluation of evidence quality， formation of recommendations. This paper described a methodological proposal for the identification of clinical questions for CPM guidelines to highlight the characteristics of Chinese patent medicine and reflect its effect in specific stage of the disease. Considering four aspects， namely， the drug of Chinese patent medicine （D）， the specific disease stage （S）， comparison （C）， and specific outcome （O）， DSCO framework has been proposed to formulate the clinical questions. Multi-source information through scientific research， policy or standard documents， and clinical data are suggested for collecting clinical questions， and clear selection criteria should be set to finalize the clinical questions to be addressed by the guideline. In addition， the above process needs to be transparently and publicly reported in order to ensure the clarity and completeness of the guidelines.