[Genetic mechanism underlying the resilience to Alzheimer's disease and its prospect for clinical application].

As the most common neurodegenerative disease, Alzheimer's disease (AD) is characterized by progressive cognitive decline and is a major threat to the health of elderly worldwide. Aside from its pathogenesis, delineation of the protective mechanism of AD is also critical for the etiological treatment. AD resilience refers to a protective mechanism which can maintain the cognitive intactness of patients despite of genetic risk factors and/or related pathology. Studies on the genetic mechanism of AD resilience are of great importance for revealing novel mechanisms and therapeutic targets, as well as optimizing polygenic risk score which can facilitate early identification and intervention for individuals at risk.

A National Cross-Sectional Survey Dataset on Common Disease and Influencing Factors of Chinese Internal Migrants in 2017.

This data article describes the dataset from a national cross-sectional questionnaire survey on Chinese internal migrants in 2017. The survey was part of the Chinese Migrants Dynamic Survey, which is an annually conducted large-scale national questionnaire survey on internal migrants. The respondents in the described dataset were migrants and registered local residents aged over 15 years old. A multistage stratified probability-proportional-to-size (PPS) sampling method based on the 2016 annual report data of China Migrant Population was adopted. The questionnaire was designed to collect demographic information of respondents and their family members, intention of migration or settlement, health status, health services accessibility, social integration, and epidemic influencing factors of common diseases, including hypertension, type 2 diabetes, diarrhea, fever, rash, icterus, conjunctival redness, cold, and other illnesses or injuries. The sample population in this survey include 13,998 internal migrants and 14,000 registered local residents from eight domestic cities / prefecture / districts across China. It is the most widely covering and highly representative dataset on common diseases and influencing factors of internal migrants in China. The dataset can be used to study common diseases and influencing factors among floating Chinese population. It provides data support for government to improve healthcare accessibility and the equity of public health services for internal migrants in China.

Biocompatible Nanotube-Strontium/polydopamine-arginine-glycine-aspartic acid coating on Ti6Al4V enhances osteogenic properties for biomedical applications.

Titanium (Ti) alloys, particularly Ti6 Al4 V, are the most commonly used biomedical implant material. Ti alloys are biologically inert, so there have been continuous efforts to improve their osteogenic properties and clinical performance. Since TiO2 nanotubes (NT) appear to be excellent drug platforms, and strontium reportedly enhances osteogenesis, we constructed a TiO2 nanotube coating on the surface of Ti6 Al4 V and immersed it in Sr (OH)2 solution in order to incorporate Sr into TiO2 nanotubes (NT-Sr). The results of field emission scanning electron microscope and X-ray diffraction analysis verified the fabrication of NT-Sr. We next added polydopamine (PDA) and cyclo- (arginine-glycine-aspartic acid-phenylalanine-cysteine) [c(RGDfC)] peptides to further promote biocompatibility of the implant. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirmed the existence of PDA and c(RGDfC). Mesenchymal stem cells (MSCs) were planted on Ti, NT, NT-Sr, NT-Sr/PDA, and NT-Sr/PDA-RGD surfaces. The adhesion and differentiation of MSCs on different surfaces were evaluated. The mRNA expression of alkaline phosphatase, runt-related transcription factor 2 (Runx2) and type I collagen (Col I) of different groups were also tested. Finally, we observed that the NT-Sr/PDA-RGD group showed significantly better performance than other groups in terms of the differentiation and osteogenesis-related gene expression of MSCs. Thus, the NT-Sr/PDA-RGD complex may be an important modification strategy for Ti, as it shows excellent osteogenic potential.

Rho-GEF Trio regulates osteosarcoma progression and osteogenic differentiation through Rac1 and RhoA.

Osteosarcoma (OS) is the most common primary bone tumor. Its high mortality rate and metastasis rate seriously threaten human health. Currently, the treatment has reached a plateau, hence we urgently need to explore new therapeutic directions. In this paper, we found that Trio was highly expressed in osteosarcoma than normal tissues and promoted the proliferation, migration, and invasion of osteosarcoma cells. Furthermore, Trio inhibited osteosarcoma cells' osteogenic differentiation in vitro and accelerated the growth of osteosarcoma in vivo. Given Trio contains two GEF domains, which have been reported as the regulators of RhoGTPases, we further discovered that Trio could regulate osteosarcoma progression and osteogenic differentiation through activating RhoGTPases. In summary, all our preliminary results showed that Trio could be a potential target and prognostic marker of osteosarcoma.

Assessment of dialysis initiation by a fuzzy mathematics equation (ADIFE): a study protocol for a randomised controlled trial.

INTRODUCTION: Starting dialysis early or late both result in a low quality of life and a poor prognosis in patients undergoing haemodialysis. However, there remains no consensus on the optimal timing of dialysis initiation, mainly because of a lack of suitable methods to assess variations in dialysis initiation time. We have established a novel equation named DIFE (Dialysis Initiation based on Fuzzy-mathematics Equation) through a retrospective, multicentre clinical cohort study in China to determine the most suitable timing of dialysis initiation. The predictors of the DIFE include nine biochemical markers and clinical variables that together influence dialysis initiation. To externally validate the clinical accuracy of DIFE, we designed the assessment of DIFE (ADIFE) study as a prospective, open-label, multicentre, randomised controlled trial to assess the clinical outcomes among patients who initiate dialysis in an optimal start dialysis group and a late-start dialysis group, based on DIFE. METHODS AND ANALYSIS: A total of 388 enrolled patients with end-stage renal disease will be randomised 1:1 to the optimal start dialysis group, with a DIFE value between 30 and 35, or the late-start dialysis group, with a DIFE value less than 30, using the Randomization and Trial Supply Management system. Participants will be assessed for changes in signs and symptoms, dialysis mode and parameters, biochemical and inflammatory markers, Subjective Global Assessment, Kidney Disease Quality of Life Short Form, Cognitive Assessment, medical costs, adverse events and concomitant medication at baseline, predialysis visiting stage and postdialysis visiting stage, every 12-24 weeks. The following data will be recorded on standardised online electronic case report forms. The primary endpoint is 3-year all-cause mortality. The secondary endpoints include non-fatal cerebrocardiovascular events, annual hospitalisation rate, quality of life, medical costs and haemodialysis related complications. ETHICS AND DISSEMINATION: Ethical approval was obtained from the Ethics Committee of the First Affiliated Hospital of Dalian Medical University China (registration no: YJ-KY-2017-119) and the ethics committees of all participating centres. The final results of the ADIFE trial will be presented to the study sponsor, clinical researchers and the patient and public involvement reference group. Findings will be disseminated through peer-reviewed journals, Clinical Practice Guidelines and at scientific meetings. TRIAL REGISTRATION NUMBER: ClinicalTrial.gov. Registry (NCT03385902); pre-results.

Glucosamine promotes chondrocyte proliferation via the Wnt/ß­catenin signaling pathway.

The present study investigated the mechanism underlying the effects of glucosamine (GlcN) on the proliferation of chondrocytes isolated from the knee cartilage of Sprague­Dawley rats. Chondrocytes were treated with various concentrations of GlcN or without GlcN. The effects of GlcN on chondrocyte proliferation were determined using reverse transcription­polymerase chain reaction, western blot analysis and immunohistochemistry. The results indicated that GlcN significantly improved chondrocyte viability, accelerated G1/S transition during progression of the cell cycle and promoted the expression of cell cycle regulatory proteins, including cyclin D1, cyclin­dependent kinase (CDK)4 and CDK6, thus indicating that GlcN may promote chondrocyte proliferation. Furthermore, GlcN upregulated the expression levels of Wnt­4, Frizzled­2 and ß­catenin, and downregulated the expression of glycogen synthase kinase­3. GlcN also promoted ß­catenin translocation; ß­catenin is able to activate numerous downstream target genes, including cyclin D1. To determine the role of the Wnt/ß­catenin signaling pathway in chondrocyte proliferation, the Wnt/ß­catenin signaling pathway was inhibited using Dickkopf­1 (DKK­1), after which chondrocytes were treated with GlcN. The results demonstrated that the expression levels of ß­catenin and cyclin D1 were decreased in chondrocytes treated with DKK­1 and GlcN. These results suggested that GlcN may promote chondrocyte proliferation via the Wnt/ß­catenin signaling pathway.

Psoralen promotes the expression of cyclin D1 in chondrocytes via the Wnt/ß-catenin signaling pathway.

Psoralen (PSO), the active ingredient of Fructus Psoraleae (FP) the dried ripe fruit of Psoralea corylifolia L., has been commonly used in traditional Chinese medicine (TCM) for the treatment of osteoarthritis (OA). We found that PSO activates cartilaginous cellular functions of rat chondrocytes in vitro. However, the effect of PSO on chondrocyte proliferation and the precise mechanisms involved remain to be elucidated. We investigated the effects of PSO on chondrocytes isolated from Sprague­Dawley (SD) rats and evaluated involvement of the Wnt/ß-catenin signaling pathway. The viability of chondrocytes treated with PSO was increased in a dose- and time-dependent manner, as assessed by MTT assay. We found that the gene expression and protein levels of Wnt-4, Frizzled-2, ß-catenin and cyclin D1 in the PSO-treated chondrocytes were significantly upregulated, while the gene expression and protein level of glycogen synthase kinase-3ß (GSK-3ß) were downregulated, compared with the untreated chondrocytes. By immunofluorescence, we also found that PSO induced ß-catenin nuclear translocation. Importantly, the expression of ß-catenin and cyclin D1 was partly inhibited by Dickkopf-1 (DKK-1), an inhibitor of the Wnt/ß-catenin signaling pathway. Additionally, Col-II expression in chondrocytes was increased after treatment with PSO. Taken together, these results indicate that PSO promotes chondrocyte proliferation by activating the Wnt/ß-catenin signaling pathway, and it may play an important role in the treatment of OA.

Bushen Zhuangjin decoction inhibits TM-induced chondrocyte apoptosis mediated by endoplasmic reticulum stress.

Chondrocyte apoptosis triggered by endoplasmic reticulum (ER) stress plays a vital role in the pathogenesis of osteoarthritis (OA). Bushen Zhuangjin decoction (BZD) has been widely used in the treatment of OA. However, the cellular and molecular mechanisms responsible for the inhibitory effects of BZD on chondrocyte apoptosis remain to be elucidated. In the present study, we investigated the effects of BZD on ER stress-induced chondrocyte apoptosis using a chondrocyte in vitro model of OA. Chondrocytes obtained from the articular cartilage of the knee joints of Sprague Dawley (SD) rats were detected by immunohistochemical staining for type Ⅱ collagen. The ER stress-mediated apoptosis of tunicamycin (TM)­stimulated chondrocytes was detected using 4-phenylbutyric acid (4­PBA). We found that 4­PBA inhibited TM-induced chondrocyte apoptosis, which confirmed the successful induction of chondrocyte apoptosis. BZD enhanced the viability of the TM-stimulated chondrocytes in a dose- and time-dependent manner, as shown by MTT assay. The apoptotic rate and the loss of mitochondrial membrane potential (ΔΨm) of the TM-stimulated chondrocytes treated with BZD was markedly decreased compared with those of chondrocytes not treated with BZD, as shown by 4',6-diamidino-2-phenylindole (DAPI) staining, Annexin V-FITC binding assay and JC-1 assay. To further elucidate the mechanisms responsible for the inhibitory effects of BZD on TM­induced chondrocyte apoptosis mediated by ER stress, the mRNA and protein expression levels of binding immunoglobulin protein (Bip), X­box binding protein 1 (Xbp1), activating transcription factor 4 (Atf4), C/EBP­homologous protein (Chop), caspase­9, caspase-3, B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (Bax) were measured by reverse transcription-polymerase chain reaction (RT-PCR) and western blot analysis. In the TM-stimulated chondrocytes treated with BZD, the mRNA and protein expression levels of Bip, Atf4, Chop, caspase-9, caspase-3 and Bax were significantly decreased, whereas the mRNA and protein expression levels of Xbp1 and Bcl-2 were significantly increased compared with the TM­stimulated chondrocytes not treated with BZD. Additionally, all our findings demonstrated that there was no significant difference between the TM­stimulated chondrocytes treated with BZD and those treated with 4­PBA. Taken together, our results indicate that BZD inhibits TM­induced chondrocyte apoptosis mediated by ER stress. Thus, BZD may be a potential therapeutic agent for use in the treatment of OA.

Clinical evaluation of Chinese patients with primary distal renal tubular acidosis.

OBJECTIVE: Distal renal tubular acidosis (dRTA) is a hyperchloremic metabolic acidosis disorder characterized by a normal anion gap with abnormal urinary hydrogen (H(+)) excretion. At present, there are few available reports regarding the clinical status of primary dRTA. The primary objective of this study was to analyze the clinical features and outcomes of primary dRTA. METHODS: This was a retrospective study performed in patients with primary dRTA who were hospitalized at Ruijin Hospital between March 1996 and July 2009; the clinical features of these patients were analyzed. RESULTS: This study included 95 consecutive inpatients: 40 men (42.11%) and 55 women (57.89%). Among them, 60 had hypokalemia (63.12%), 29 had complete dRTA and 66 had incomplete dRTA. The mean urine calcium levels of the patients with and without urinary lithiasis were 0.10±0.04 and 0.07±0.05 mmol/24 h・kg, respectively (p=0.04). The blood pH values of the patients with and those without bone disease were 7.37±0.06 and 7.32±0.06, respectively (p=0.01). A total of 8.33% (8/27) of the patients had tubular proteinuria. CONCLUSION: Hypokalemia is the most common clinical manifestation of primary dRTA. Primary dRTA can also be accompanied by proximal tubular dysfunction. Controlling the urine calcium and citrate levels is crucial for the treatment of nephrocalcinosis and/or nephrolithiasis, while restoring the blood pH to the normal level is essential for controlling bone disease.