A Highly Sensitive and Selective Fluorescent Sensor for Folic Acid Detection Based on D-penicillamine Stabilized Ag/Cu Alloy Nanoclusters.

In this work, a highly sensitive and selective method for detecting folic acid (FA) was developed using D-penicillamine (DPA) stabilized Ag/Cu alloy nanoclusters (DPA@Ag/Cu NCs). The yellow emission of DPA@Ag/Cu NCs was found to be quenched upon the addition of FA to the system. The fluorescence intensity quenching value demonstrated a linear relationship with FA concentrations ranging from 0.01 to 1200 µM, with a limit of detection (LOD) of 5.3 nM. Furthermore, the detection mechanism was investigated through various characterization analyses, including high resolution transmission electron microscopy, fluorescence spectra, ultraviolet-visible absorption spectra, and fluorescence lifetime. The results indicated that the fluorescence quenching induced by FA was a result of electron transfer from FA to the ligands of DPA@Ag/Cu NCs. The selectivity of the FA sensor was also evaluated, showing that common amino acids and inorganic ions had minimal impact on the detection of FA. Moreover, the standard addition method was successfully applied to detect FA in human serum, chewable tablets and FA tablets with promising results. The use of DPA@Ag/Cu NCs demonstrates significant potential for detecting FA in complex biological samples.

Joint-tissue integrative analysis identifies high-risk genes for Parkinson's disease.

The loss of dopaminergic neurons in the substantia nigra and the abnormal accumulation of synuclein proteins and neurotransmitters in Lewy bodies constitute the primary symptoms of Parkinson's disease (PD). Besides environmental factors, scholars are in the early stages of comprehending the genetic factors involved in the pathogenic mechanism of PD. Although genome-wide association studies (GWAS) have unveiled numerous genetic variants associated with PD, precisely pinpointing the causal variants remains challenging due to strong linkage disequilibrium (LD) among them. Addressing this issue, expression quantitative trait locus (eQTL) cohorts were employed in a transcriptome-wide association study (TWAS) to infer the genetic correlation between gene expression and a particular trait. Utilizing the TWAS theory alongside the enhanced Joint-Tissue Imputation (JTI) technique and Mendelian Randomization (MR) framework (MR-JTI), we identified a total of 159 PD-associated genes by amalgamating LD score, GTEx eQTL data, and GWAS summary statistic data from a substantial cohort. Subsequently, Fisher's exact test was conducted on these PD-associated genes using 5,152 differentially expressed genes sourced from 12 PD-related datasets. Ultimately, 29 highly credible PD-associated genes, including CTX1B, SCNA, and ARSA, were uncovered. Furthermore, GO and KEGG enrichment analyses indicated that these genes primarily function in tissue synthesis, regulation of neuron projection development, vesicle organization and transportation, and lysosomal impact. The potential PD-associated genes identified in this study not only offer fresh insights into the disease's pathophysiology but also suggest potential biomarkers for early disease detection.

The optimal cut-off value of five-time chair stand test for assessing sarcopenia among Chinese community-dwelling older adults.

BACKGROUND: The five-time chair stand test (5CST) as an indicator of muscle strength and physical function is the first step in assessing sarcopenia. We aimed to determine the optimal cut-off value of the 5CST for assessing older adults with sarcopenia in the Chinese community. METHODS: We used a stratified cluster random sampling method to recruit older adults from Chinese communities. The handgrip strength was assessed using an electronic handgrip dynamometer. The 5CST and gait speed were assessed by the trained researchers. The bioimpedance analysis device was used to evaluate the skeletal muscle index. We used the Asian Working Group for Sarcopenia diagnosis criteria as the gold standard. According to the receiver operating characteristic curve, we determine the optimal cut-off value using the Youden index. RESULTS: A total of 1027 participants were included in this analysis, including 337 men and 690 women with an average age of 70.35 ± 7.24 years. The prevalence of sarcopenia in total participants was 24.9%. The optimal cut-off value of 5CST in the total population was 10.9 s. Stratified by age and gender, for the older adults aged 60-69 years, the optimal cut-off values were 9.2 s in men and 10.8 s in women; for the older adults aged 70-79 years, cut-off values were 10.2 s in men and 10.9 s in women; and for the older adults over 80 years, cut-off values were 14.0 s in men and 11.5 s in women (all P < 0.001). The areas under the curve of 5CST were 0.632 in men and 0.650 in women (both P < 0.001). Using the newly defined cut-off values, the prevalence of sarcopenia increased significantly (P < 0.001). CONCLUSIONS: We determined the optimal cut-off value of the 5CST for assessing older adults with sarcopenia in the Chinese community, and this cut-off can significantly improve the detection rate of sarcopenia. The cut-off determined in our study will help community workers detect more people with sarcopenia and benefit from early intervention and management of sarcopenia in practice.

Visible-Light Photoredox-Catalyzed Three-Component Reaction of Carbazoles with Alkenes and S-(Difluoromethyl)sulfonium Salt: A Practical Approach to Access Difluoroalkyl-Functionalized Carbazoles.

A mild and elegant multicomponent protocol for construction of CF2H-containing carbazoles was accomplished by visible-light photoredox catalysis with formation of two new C-C bonds in a single step to deliver a wide variety of structurally diverse difluoroalkylated carbazoles in moderate to good yields, featuring mild reaction conditions, synthetic simplicity, broad substrates, and good functional group tolerance.

Heel bone mineral density and various oral diseases: a bidirectional Mendelian randomization.

INTRODUCTION: Observational studies demonstrated that the relationship between bone mineral density and oral diseases is mixed. To access the association between heel bone mineral density and various oral diseases, we conducted the Mendelian randomization analysis to explore the association. MATERIALS AND METHODS: Two-sample bidirectional Mendelian analysis was used to explore the relationship between heel bone mineral density and various oral diseases. The inverse-variance weighted (IVW) was used as the primary effect estimate, and various methods were applied to test the reliability and stability of the results, namely MR-Egger, weighted median, simple mode, and weighted mode. RESULTS: This study showed that there was a negative relationship between heel BMD and periodontitis when heel BMD was used as an exposure factor and periodontitis as an outcome factor (IVW OR = 0.85; 95% CI, 0.75-0.95; p = 0.005). Bidirectional Mendelian randomization showed that there was no statistically significant association between periodontitis and heel bone mineral density when chronic periodontitis was the exposure factor (p > 0.05). And there was no significant relationship between heel bone mineral density and other oral diseases (dental caries, diseases of pulp and periapical tissues, impacted teeth, cleft lip, and cleft palate, oral and oropharyngeal cancer) (p > 0.05). CONCLUSION: This study showed that there was a negative relationship between heel bone density and periodontitis, and the decrease in heel bone density could promote the occurrence of periodontitis. In addition, there was no statistically significant relationship between heel bone density and other oral diseases.

Visible-light photoredox-catalyzed radical aryldifluoromethylation of N-arylacrylamides with S-(difluoromethyl)sulfonium salt.

A facile and highly efficient visible-light photoredox-catalyzed protocol for aryldifluoromethylation of acrylamides was developed using S-(difluoromethyl)sulfonium salt as the difluoromethyl source. With this method, pharmaceutically interesting CF2H-containing oxindoles were readily accessed from N-arylacrylamides, and this method featured mild reaction conditions, a broad scope of substrates, good tolerance of functional groups, and good to excellent yields. Control experiments revealed that this protocol proceeded through a difluoromethylation/cyclization cascade process.

Mesenchymal stem cells, extracellular vesicles, and transcranial magnetic stimulation for ferroptosis after spinal cord injury.

Spinal cord injury is characterized by different aetiologies, complex pathogenesis, and diverse pathological changes. Current treatments are not ideal, and prognosis is generally poor. After spinal cord injury, neurons die due to various forms of cell death. Among them, ferroptosis causes dysfunction after spinal cord injury, and no existing traditional treatments have been indicated to block its occurrence. Meanwhile, emerging therapies using mesenchymal stem cells, extracellular vesicles, and transcranial magnetic stimulation therapy are promising for reversing spinal cord neuronal ferroptosis after spinal cord injury. However, no definitive studies have demonstrated the effectiveness of these approaches. This review summarizes the existing research on the mechanisms of ferroptosis; ferroptosis after spinal cord injury; treatment of spinal cord injury with mesenchymal stem cells, extracellular vesicles, and transcranial magnetic stimulation; and treatment of ferroptosis using mesenchymal stem cells, extracellular vesicles, and transcranial magnetic stimulation. Inhibiting ferroptosis can promote the reversal of neurological dysfunction after spinal cord injury. In addition, mesenchymal stem cells, extracellular vesicles, and transcranial magnetic stimulation can reverse adverse outcomes of spinal cord injury and regulate ferroptosis-related factors. Thus, it can be inferred that mesenchymal stem cells, extracellular vesicles, and transcranial magnetic stimulation have the potential to inhibit ferroptosis after spinal cord injury. This review serves as a reference for future research to confirm these conclusions.

Facile Entry to Pharmaceutically Important 3-Difluoromethyl-quinoxalin-2-ones Enabled by Visible-Light-Driven Difluoromethylation of Quinoxalin-2-ones.

CF2H moiety has a significant potential utility in drug design and discovery, and the incorporation of CF2H into biologically active molecules represents an important and efficient strategy for seeking lead compounds and drug candidates. On the other hand, quinoxalin-2-one is of great interest to pharmaceutical chemists as a common skeleton frequently occurring in plenty of natural products and bioactive compounds. Herein, we reported a practical and efficient protocol for the synthesis of 3-CF2H-quinoxalin-2-ones. Thus, in the presence of 3 mol% of photocatalyst and S-(difluoromethyl)sulfonium salt as difluoromethyl radical sources, a wide range of quinoxalin-2-ones readily underwent a visible-light redox-catalyzed difluoromethylation reaction, to deliver structurally diverse 3-difluoromethyl-quinoxalin-2-ones. We believe that this would facilitate increasing chances and possibilities for seeking potential lead compounds and drug candidates and further boost the development of fluorine-containing pharmaceuticals.

Can dietary patterns prevent cognitive impairment and reduce Alzheimer's disease risk: Exploring the underlying mechanisms of effects.

Alzheimer's disease (AD) is one of the fastest growing cognitive decline-related neurological diseases. To date, effective curative strategies have remained elusive. A growing body of evidence indicates that dietary patterns have significant effects on cognitive function and the risk of developing AD. Previous studies on the association between diet and AD risk have mainly focused on individual food components and specific nutrients, and the mechanisms responsible for the beneficial effects of dietary patterns on AD are not well understood. This article provides a comprehensive overview of the effects of dietary patterns, including the Mediterranean diet (MedDiet), dietary approaches to stop hypertension (DASH) diet, Mediterranean-DASH diet intervention for neurological delay (MIND), ketogenic diet, caloric restriction, intermittent fasting, methionine restriction, and low-protein and high-carbohydrate diet, on cognitive impairment and summarizes the underlying mechanisms by which dietary patterns attenuate cognitive impairment, especially highlighting the modulation of dietary patterns on cognitive impairment through gut microbiota. Furthermore, considering the variability in individual metabolic responses to dietary intake, we put forward a framework to develop personalized dietary patterns for people with cognitive disorders or AD based on individual gut microbiome compositions.

Thermal strain and fluid balance during a 72-km military route march in a field setting.

Introduction: A physiological profiling study was conducted to evaluate thermal strain as well as fluid and electrolyte balances on heat-acclimatised men performing a 72-km route march in a field setting. Methods: 38 male soldiers (age range 18-23 years) participated in the study, as part of a cohort that marched for 72 km, with loads for about 26 hours. Core temperature and heart rate sensors were used for the duration of the march. Fluid and food intake and output were monitored for the duration of the march. Blood samples were taken one day before the march (pre-march), immediately after the march (Post 1) and on the 15th day after the march to ascertain recovery (Post 2) to assess fluid and electrolyte profiles. Results: Mean core temperature was within safe limits, ranging from 37.1 to 38.1°C throughout the march. There was an overall decrease in serum sodium levels, a decline in serum sodium concentration in 28 participants and three instances of hyponatraemia (serum sodium concentration <135 mmol/L). Conclusion: Our study found low thermal strain heat-acclimatised individuals during a 72-km route march. However, there was an overall decrease in serum sodium levels, even when the participants were allowed to drink ad libitum. Challenges of exercise-associated hyponatraemia during prolonged activities remain to be addressed.

Difluoromethyl Radical Triggered Tandem Reaction of N-Allyl Amides to Difluoromethylated ß-Amino Alcohols by Photoredox Catalysis.

An elegant tandem reaction process for transferring N-allyl amide into CF2H-ß-amino alcohol is described. This approach proceeded smoothly under visible light irradiation in the presence of a 3 mol % Ir complex, exhibiting a broad substrate scope and functional group tolerance, and a variety of CF2H-ß-amino alcohols were readily accessed in good to excellent yields under mild conditions. The reliable mechanistic studies revealed that sequential difluoromethyl radical addition/carbocation trap/rearrangement is involved.

[Construction and Anti-tumor Effect Evaluation of a Dual-Responsive Hyaluronic Acid Carbon Quantum Dot-Gelatin Nano-Drug Delivery System].

OBJECTIVE: To construct a pH and matrix metalloproteinase (MMP) dual-responsive nano drug delivery system with adjustable particle size so as to synergistically enhance the retention and penetration of chemotherapeutic drugs in tumor tissues and improve tumor treatment effect. METHODS: Hyaluronic acid (HA) carbon quantum dots (CD) coupled with gelatin nanoparticle (GNP) were constructed, and were connected with doxorubicin (DOX), a chemotherapeutic drug, through pH-sensitive imine to produce GNP@HA-CD-DOX nanoparticles. The changes of particle size, drug release behavior, hemocompatibility, cell uptake and deep penetration of tumor spheroids, in vivo tumor targeting and therapeutic effect were analyzed. RESULTS: GNP@HA-CD-DOX nanoparticles had a particle size of (162.93±2.55) nm, which could be degraded to release HA-CD-DOX with a particle size of about 40 nm under the treatment of MMP. The drug loading of DOX was (4.94±0.22)%. DOX was released in the tumor microenvironment and lysosomes in response to the low pH. No obvious hemolysis was observed in GNP@HA-CD-DOX. GNP@HA-CD-DOX showed a reduction in particle size after co-incubation with MMP-2. The MMP-sensitive GNP@HA-CD-DOX had significantly improved cell uptake and better deep penetration in tumor spheres. GNP@HA-CD-DOX displayed better distribution in tumor and anti-tumor ability in tumor-bearing mice compared with the small particle size HA-CD-DOX group. In addition, it has better safety. CONCLUSION: The pH and MMP dual-sensitive nano-tech drug delivery system with adjustable particle sizes synergistically enhances the retention and deep penetration of drugs in tumors as well as the anti-tumor effect, suggesting new approaches to tumor treatment.

A new polyacetylene from the stems and leaves of Chrysanthemum morifolium Ramat / 药学学报

Eight polyacetylenes were isolated from the extract of the stems and leaves of Chrysanthemum morifolium by various chromatographic methods. Their structures were determined as 2E,4E,12Z-tetradecatriene-1-pyrrolidine-1-oxo-8,10-diynoic (1), tetradeca-2E,4E,12E-trien-8,10-diynoic acid pyrrolidide (2), tetradeca-2E,4E-dien-8,10-diynoic acid pyrrolidide (3), tetradeca-2E,4E,10Z-trien-8-ynoic acid pyrrolidide (4), 2E,4E,12E-tetradecatriene-8,10-diynoic acid isobutylamide (5), 2E,4E-undecyldiene-8,10-diynoic acid isobutylamide (6), 2E,4E,10E-N-isobutyl-2,4,10-tetradecatrien-8-ynoic acid amide (7), and undeca-2E,4E-diene-8,10-diynoic acid phenylethylamide (8) by spectroscopic methods, including UV, IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR spectra. Among them, compound 1 is a new polyacetylene, and compounds 2-8 were isolated from this plant for the first time. Compounds 5-8 inhibited the proliferation of A549 cell significantly at certain concentration, showing potent antitumor activity.

A randomized controlled study on color stability of tetracycline teeth restored with ceramic veneer / 华西口腔医学杂志

OBJECTIVES@#This study aimed to evaluate the color stability of tetracycline teeth restored with ceramic veneers of different thicknesses combined with different resin cement systems after aging.@*METHODS@#Twenty patients with tetracycline teeth, including two maxillary central incisors, were selected clinically. The patients were randomly divided into four groups and restored with 0.5 and 0.75 mm ceramic veneers by using a veneer adhesive system, either with light-cured or dual-cured reaction. The color difference (ΔE) values after cementation and 1, 6, 12, and 24 months of use were obtained by quantification of L*, a*, and b* values with a colorimeter. The results were analyzed statistically with two-way ANOVA and Student's @*RESULTS@#The ΔE values of ceramic veneers detected after aging were less than 2.25. The 0.5 mm groups exhibited greater color change than the 0.75 mm-thick veneers (@*CONCLUSIONS@#Resin cements and veneer thickness influence the color of ceramic veneers after aging. Cementation of veneers with either dual- or light-cured resin cements does not affect the long-term color stability of tetracycline teeth differently.

The Inhibiting Effect of Autophagy Inhibitor ROC-325 on Multiple Myeloma / 中国实验血液学杂志

OBJECTIVE@#To investigate the effects of autophagy inhibitor ROC-325 and its combination with bortezomib on the proliferation, apoptosis and autophagy of multiple myeloma cell lines.@*METHODS@#Multiple myeloma cells were treated with ROC-325 at different concentration. The cell proliferation was detected by CCK-8. Apoptosis was determined by Caspase-3/7 and Caspase-9 activity assays. Autophagy was detected by monodansylcadaverine staining. The apoptosis-related proteins (PARP and Caspase-3) and autophagy-related proteins (P62, Beclin-1, and LC3A/B) were analyzed by Western blot. The combined effect with bortezomib on bortezomib-resistant cell line was detected by CCK-8.@*RESULTS@#ROC-325 inhibited the proliferation of RPMI 8226, RPMI 8226-BTZ100, U266 and IM9 cells in a dose-dependent manner (r=-0.8275, r=-0.9079, r=-0.9422, r=-0.9305), the 72 h IC@*CONCLUSION@#ROC-325 can inhibit the proliferation, induce the apoptosis of myeloma cells through the mitochondrial pathway, inhibit the autophagy of myeloma cells by affecting the fusion of autophagosomes and lysosomes, and overcome bortezomib resistance by the combination of ROC-325 with bortezomib.

A new alkaloid from Rehmanniae Radix Preparata / 药学学报

The chemical constituents of Rehmanniae Radix Preparatawere prepared according to the traditional method of "jiu zheng jiu shai" and investigated using multiple chromatographic methods. Six alkaloids were isolated and their structures were elucidated from spectral data and physicochemical properties, as follows: rehmanniae alkaloid A (4-{[(5-O-á-D-galactopyranosyloxy)methyl]-1H-pyrrole-2-carbaldehyde-1-yl}butyric acidmethyl ester) (1), baimantuoluoamide B (2), capparisine C (3), harman-3-carboxylic acid (4), (2S)-1-[2-(furan-2-yl)-2-oxoethyl]-5-oxopyrrolidine-2-carboxylate (5), and 1-[2-(furan-2-yl)-2-oxoethyl]pyrrolidin-2-one (6). Among them, compound 1 is a new alkaloid. Compounds 2-6 were newly isolated from Rehmannia glutinosa Libosch.The effect of compounds 1-6 on NRK-52e cell injury induced by LPS was investigated. The results show that compounds 1-3 exhibit protective effects against LPS-induced damage to NRK-52e cells.

Dendrobium officinale Kimura et Migo and American ginseng mixture: A Chinese herbal formulation for gut microbiota modulation / 中国天然药物

Dendrobium officinale Kimura et Migo (D. officinale) is a famous traditional Chinese medicine (TCM). A mixture of D. officinale and American ginseng has been shown to enhance cell-mediated immunity, humoral immunity, and monocyte/macrophage functions in mice. Here, the effects of a D. officinale and American ginseng mixture on the structure of gut microbial community in dogs were examined using high-throughput 16S rRNA gene amplicon sequencing. The data revealed that while the mixture did not change the diversity of gut microbial community significantly, differences among individuals were significantly reduced. Furthermore, the mixture-responsive operational taxonomic units (OTUs) exhibited a phase-dependent expression pattern. Fifty-five OTUs were found to exhibit a mixture-induced expression pattern, among which one third were short-chain fatty acid (SCFA)-producing genera and the others were probiotic genera included Lactobacillus spp., Sutterella, Alistipes, Anaerovorax, Bilophila, Coprococcus, Gordonibacter, Oscillibacter, among others. By contrast, 36% of the OTUs exhibiting a mixture-repressed expression pattern were disease-associated microorganisms, and six genera, namely Actinomyces, Escherichia/Shigella, Fusobacterium, Slackia, Streptococcus and Solobacterium, were associated with cancer. In addition, five genera were closely associated with diabetes, namely Collinsella, Rothia, Howardella, Slackia and Intestinibacter. Our results indicate that this D. officinale and American ginseng mixture may be used as a prebiotic agent to enhance SCFA-producing genera and prevent gut dysbiosis.

Chemical constituents from Calystegia sepium / 中草药

Objective To study the chemical constituents from Calystegia sepium. Methods The compounds were isolated and purified by silica gel column chromatography, Sephadex LH-20, ODS column chromatography, preparative HPLC and so on. Their structures were determined on the basis of physicochemical properties and their spectroscopic data, as well as literatures. Results A total of 20 compounds were separated and identified as tyrosol (1), quercetin-3-O-β-D-glucopyranoside (2), scutellarein-7-O-β- glucopyranoside (3), kaempferol-3-O-β-D-glucopyranoside (4), kaempferol-3-O-galactoside (5), kaempferol-3-O-β-robinobioside (6), nicotiflorin (7), rutin (8), uridine (9), tachioside (10), 2-methoxy-4-(2’-hydroxyethyl)-phenyl-1-O-β-D-glucopyranoside (11), 4-hydroxyphenethylol-4-O-β-D-glucopyranoside (12), polybotrin (13), pyridine-3,5-dicarboamide (14), skimmin (15), benzylalcohol-β-D-glucopyranoside (16), 5-hydroxyl-2-hydroxymethylpyridine (17), picein (18), 5-hydroxymethyl-furaldehyde (19), and sessiline (20). Conclusion Compounds 1-20 are isolated from Calystegia sepium for the first time.

Update: Efficacy of Military Fluid Intake Guidance.

BACKGROUND: Fluid intake during military training is prescribed based on the interactions among work rates, environmental conditions, and uniform configurations. The efficacy of this guidance has not been empirically assessed in over a decade. To determine the acceptability of the fluid intake guidance, sweat losses were measured in a variety of conditions with modern uniform/body armor configurations and were then compared to prescribed fluid intakes for each condition (workload, environment, clothing). METHODS: Whole body sweat losses of 324 Soldiers and 14 model simulations were measured under a variety of work intensities ((Watts) easy, moderate, hard), work durations (2-25 h), environmental conditions (White-Black flag), and uniform configurations (including Army Combat Uniform and body armor). Whole body sweat losses were then calculated relative to 4 h drinking guidance and in accordance with TB MED 507 recommended work/rest ratios. The differences between the prescribed fluid intake and sweat loss were calculated and expressed as a percent loss or gain of body weight. Values within a threshold of ±2% body water flux (BWF) were deemed an acceptable conservative starting point for performance and health concerns. FINDINGS: Values within ±2% BWF numbered 309/338; 25 of 338 observations exceeded the +2% BWF while 4 of 338 observations exceeded the -2% BWF. When total fluid restriction was simulated, all experienced body weight loss with 151 of 338 observations exceeding the -2% BWF. DISCUSSION: When calculated using actual measured sweating rates from the laboratory and model simulations, current fluid intake guidance appears to predict with 91.4% accuracy the volume of fluid required to maintain a proper euhydrated state (±2%) during 4 h of exercise. Simulations of total fluid restriction support the necessity for fluid intake guidance so that the Warfighter's performance does not degrade. It is recommended that the current military fluid intake guidance focuses on methods for accurately tracking fluid intakes.

The preliminary establishment of the index system for the comprehensive evaluation model of long term care for the elderly / 中国实用护理杂志

Objective To construct a comprehensive evaluation model of long-term care for the elderly based on the situation of our country,which is suitable for the family,community and the pension service organization. Methods The model index item pool (7 one class indexes and 133 two class indexes) formed by literature research, theoretical extraction and qualitative interview were taken as the research object.To screen the model parameters by using the Delphi method,then formed a index system of hierarchical comprehensive evaluation model of long term care for the elderly. Results 25 experts were from 10 provinces of a total of 23 Medical Colleges and affiliated hospital,positive coefficients for the first round of 83.33% and the second round of 100.00%,the average value of the two authority coefficients were both >0.90, the coordination coefficient of the evaluation index for the first round of 0.221 and the second round of 0.266(both P<0.05).The primary model index system consists of 7 first level indicators,a total of 13 secondary indicators.Among them,the"daily life ability","cognitive ability","falling risk"and"pressure sore risk" evaluation were using very mature scales, the "medical care project", "abnormal performance/symptom" and "self care knowledge needs" evaluation were independently established in this study. Conclusions Preliminary construction process of the index system for the comprehensive evaluation model of long term care for the elderly was rigorous and had better theoretical support,and the Delphi method experts had higher degree of attention and participate in the research content, experts had good representativeness,can effectively guarantee the reliability of the selected items.