Edaravone Alleviates Traumatic Brain Injury by Inhibition of Ferroptosis via FSP1 Pathway.

Traumatic brain injury (TBI) is a highly severe form of trauma with complex series of reactions in brain tissue which ultimately results in neuronal damage. Previous studies proved that neuronal ferroptosis, which was induced by intracranial haemorrhage and other reasons, was one of the most primary causes of neuronal damage following TBI. However, the association between neuronal mechanical injury and ferroptosis in TBI and relevant treatments remain unclear. In the present study, we first demonstrated the occurrence of neuronal ferroptosis in the early stage of TBI and preliminarily elucidated that edaravone (EDA), a cerebroprotective agent that eliminates oxygen radicals, was able to inhibit ferroptosis induced by TBI. A cell scratching model was established in PC12 cells, and it was confirmed that mechanical injury induced ferroptosis in neurons at the early stage of TBI. Ferroptosis suppressor protein 1 (FSP1) plays a significant role in inhibiting ferroptosis, and we found that iFSP, a ferroptosis agonist which is capable to inhibit FSP1 pathway, attenuated the anti-ferroptosis effect of EDA. In conclusion, our results suggested that EDA inhibited neuronal ferroptosis induced by mechanical injury in the early phase of TBI by activating FSP1 pathway, which could provide evidence for future research on prevention and treatment of TBI.

Construction of a prognostic model for autophagy in Wilm's tumor.

BACKGROUND: Wilm's tumor (WT) is one of the most common childhood urological tumors, ranking second in the incidence of pediatric abdominal tumors. The development of WT is associated with various factors, and the correlation with autophagy is currently unclear. PURPOSE: To develop a new prognostic model of autophagy-related genes (ATG) for WT. METHODS: Using the Therapeutically applicable research to generate effective treatments (TARGET) database to screen for differentially expressed ATGs in WT and normal tissues. ATGs were screened for prognostic relevance to WT using one-way and multifactorial Cox regression analyses and prognostic models were constructed. The risk score was calculated according to the model, and the predictive ability of the constructed model was analyzed using the ROC (receiver operating characteristic) curve to verify the significance of the model for the prognosis of WT. RESULTS: Sixty-eight differentially expressed ATGs were identified by univariate Cox regression analysis, and two critical prognostic ATGs (CXCR4 and ERBB2) were identified by multivariate Cox regression analysis. Patients were divided into high-risk and low-risk groups according to the differential expression of these two ATGs. Kaplan-Meier (KM) curves showed a significant difference in survival time between the two groups. The critical prognostic ATGs were combined with race, age, and stage in a multifactorial regression analysis, and the final prognostic model was produced as a line graph. CONCLUSION: The prognostic model of autophagy-related genes composed of the CXCR4 gene and ERBB2 gene has a specific predictive value for the prognosis of WT, and the present study provides a clear basis for future research on biomarkers and therapeutic targets.

Different responses of taxonomic and functional trait structure of benthic macroinvertebrate assemblages to eutrophication in a large Chinese freshwater lake.

Functional trait measures have the potential to represent local habitat conditions and are considered promising tools for biomonitoring and bioassessment programs. Macroinvertebrates are an ecologically significant group in freshwater ecosystems and possess a range of functional traits which are employed to assess ecological quality. Nevertheless, the relationships between macroinvertebrate functional structure and anthropogenic disturbances remain poorly understood. In this study, we conducted a comparison of how functional trait-based and taxonomy-based composition of macroinvertebrate assemblages responded to eutrophication in Lake Taihu, a typical large eutrophic freshwater lake in China. Specifically, we examined both the taxonomy-based and trait-based compositions of benthic macroinvertebrates varied along the eutrophication gradient. Eutrophication was associated with remarkable decreases in the abundance of gastropod taxa and increases in Oligochaeta and Chironomidae. Ten categories belonging to six traits were significantly different among three site groups. The eutrophic and transition sites showed higher abundance of Size2, burrowers, and integument-respiration organisms than macrophytic sites, whereas abundance of Size1, conical-shaped, sprawlers, scrapers, and lung-respiration were higher in macrophytic sites. Both taxonomic (36.8%) and functional compositions (39.8%) of macroinvertebrate assemblages were influenced by the same variables: CODMn and transparency. Our study showed that macroinvertebrate trait-based approaches can be considered a useful supplement to traditional taxonomic approach for biomonitoring programs in freshwater lakes.

Overexpression of FSP1 Ameliorates ferroptosis via PI3K/ AKT /GSK3ß pathway in PC12 cells with Oxygen-Glucose Deprivation/Reoxygenation.

After ischemia and reperfusion (I/R), nerve cell damage is a pathogenic process that involves numerous molecular processes. In the last ten years, one new classification of programmed cell death is ferroptosis. More recent research has demonstrated that ferroptosis has a role in a variety of neurological disorders, including stroke, cancer, and neurodegenerative illnesses. Ferroptosis suppressor protein 1 (FSP1) plays a significant role in inhibiting ferroptosis. The purpose of this work is to determine how overexpression of FSP1 affects the ferroptosis of PC12 cells under the condition of oxygen-glucose deprivation/reoxygenation (OGD/R). The expression of FSP1 was regulated by lentivirus transfection technology. Western blot and immunofluorescence were used to measure protein levels related to ferroptosis and the PI3K/AKT/GSK3ß signal pathway. Determine cell viability using the appropriate kit. Mitochondrial structural morphology was checked by transmission electron microscopy in PC12 cells. Reactive oxygen species (ROS) and Malondialdehyde (MDA) were quantified using the relevant kits. OGD/R induced ferroptosis in PC12 cells, however, FSP1 overexpression reverses ferroptosis and promotes cell viability, lowering ROS and MDA content. The expression of FSP1 decreased in OGD/R0h and OGD/R6h and rebounded in OGD/R24h and OGD/R48h. During the processes of OGD/R-induced ferroptosis, FSP1 overexpression significantly stimulated PI3K/AKT/GSK3ß pathway, but LY294002 weakens the protective effect of FSP1 overexpression. Our outcomes demonstrate that overexpression of FSP1 markedly enhances the ability to resist ferroptosis via the PI3K/AKT/GSK3ß pathway. The above results may provide a new preliminary lead for the treatment of the cerebral ischemia-reperfusion injury.

Ammonium tetrathiomolybdate relieves oxidative stress in cisplatin-induced acute kidney injury via NRF2 signaling pathway.

Cisplatin is an efficient chemotherapeutic agent for various solid tumors, but its usage is restricted by nephrotoxicity. A single dose of cisplatin can cause acute kidney injury (AKI), which is characterized by rapid reduction in kidney function. However, the current therapies, such as hydration, are limited. It is vital to develop novel therapeutic reagents that have both anticancer and renoprotective properties. The objective of this study was to determine whether ammonium tetrathiomolybdate (TM), a copper chelator used to treat cancer and disorders of copper metabolism, may offer protection against cisplatin-induced AKI. In this study, we demonstrated that TM treatment had antioxidative effects and mitigated cisplatin-induced AKI both in vivo and in vitro. Mechanically, TM inhibited NRF2 ubiquitination, which activated the NRF2 pathway in HK-2 cells and promoted the expression of target genes. It should be noted that the protective effect conferred by TM against cisplatin was compromised by the knockdown of the NRF2 gene. Furthermore, TM selectively activated the NRF2 pathways in the liver and kidney. The current study provided evidence for additional clinical applications of TM by showing that it activates NRF2 and has a favorable therapeutic impact on cisplatin-induced AKI.

Inhibition of ACSF2 protects against renal ischemia/reperfusion injury via mediating mitophagy in proximal tubular cells.

Acute kidney injury (AKI) is a prevalent clinical condition caused by sepsis and ischemia reperfusion (IR) injury. The principal driver of IR-induced AKI involves renal tubular structural changes triggered by the impairment of function in renal tubular cells. The target gene, Acyl-CoA Synthetase Family Member 2 (ACSF2), was retrieved from the GEO database based on high specific expression in renal tubular cells and location in mitochondria. Here, we substantiate that ACSF2 is specifically localized in the mitochondria of the renal tubular epithelium. Functionally silencing ACSF2 in HK2 cells enhanced hypoxia-reoxygenation (HR)-induced mitophagy, restored mitochondrial function and decreased the production of mitochondrial superoxide. Our study demonstrated that these effects were reversed by silencing Bcl-2 19-kDa interacting protein 3 (BNIP3), a receptor regulating mitophagy. In vivo, ACSF2 knockdown significantly enhanced IR-induced mitophagy and improved renal function in mice with IR injury. Conversely, BNIP3 knockdown inhibited mitophagy and exacerbated renal damage in ACSF2-knockdown mice with IR injury. In conclusion, our study demonstrated that inhibition of ACSF2 enhances mitophagy, restoring mitochondrial function and protects against IR-induced AKI, providing a new target and potential strategy for therapy.

Substrate Stiffness Regulates the Proliferation and Apoptosis of Periodontal Ligament Cells through Integrin-Linked Kinase ILK.

The hallmark of orthodontic tooth movement (OTM) is time-consuming during clinical treatments. The acceleration of OTM through modulating proliferation and apoptosis of periodontal ligament cells (PDLCs) possesses the potential application in clinical treatments. Here, we established an in vitro model with a graded increase in substrate stiffness to investigate the underlying mechanism of proliferation and apoptosis of PDLCs. The role of the integrin-linked kinase (ILK) in response to substrate stiffness was investigated by the depletion model of PDLCs. We found that the proliferation and apoptosis of PDLCs show a stiffness-dependent property with stiffer substrates favoring increased bias at the transcript level. Depleting integrin-linked kinase diluted the correlation between PDLCs behaviors and substrate stiffness. Our results suggest that ILK plays a significant role in modulating PDLC proliferation and apoptosis and can serve as a potential target for accelerating OTM.

ILK regulates osteogenic differentiation of Human Periodontal Ligament Stem Cells through YAP-mediated Mechanical Memory.

Mechanical memory meant the mechanical properties of the matrix could influence the cell fate even after the matrix was changed and has been justified in many kinds of cells. To utilize the phenomenon to improve periodontal tissue engineering, we studied whether mechanical memory existed in human periodontal ligament stem cells and testified if ILK plays a role in this process. The substrate of different stiffness was fabricated by gelatin methacrylate hydrogel. Two groups of hPDLSCs with stiff (St) and soft (So) matrix, respectively, were cultivated. Then, half of the cells exchanged their matrix stiffness in the fourth passage and therefore So, St, So-St, and St-So were formed. Morphology of hPDLSCs and intracellular location of YAP was observed via fluorescence staining, osteogenic differentiation of hPDLSCs was assessed by real-time PCR, ALP staining, and Western blot. Then, all these were reassessed after the ILK gene had been knocked down. The results showed that morphology and YAP location of hPDLSCs were different between matrix changed and unchanged groups; osteogenic genes expression, ALP staining, and Western blot also varied. After the ILK gene had been knocked down, the YAP location and osteogenic activity of hPDLSCs were significantly influenced. Thus, it could be concluded that mechanical memory exists in hPDLSCs; ILK is involved in this process.

Cu catalyzed [4 + 2] cycloaddition for the synthesis of highly substituted 3-fluoropyridines.

A copper catalyzed annulation-aromatization of benzyl trifluoromethyl ketimines with 3-acryloyloxazolidin-2-ones for the synthesis of 3-fluoropyridines through double C-F bond cleavages has been developed. In this approach, the annulation occurred between the in situ formed dienes from trifluoromethyl ketimines via the first C-F bond cleavage and 3-acryloyloxazolidin-2-ones. Then the aromatization afforded 3-fluoropyridines in moderate yields through the second C-F bond cleavage. The 3-fluoropyridine products could be further hydrolyzed to multi-substituted 3-pyridinecarboxylic acids.

Safety evaluation on concomitant immunization with inactivated poliomyelitis vaccine produced from Sabin strains and other vaccines (from 2015 to 2020).

OBJECTIVE: To evaluate the safety of concomitantly administering inactivated poliomyelitis vaccine produced from Sabin strains (sIPVs) with other vaccines. METHODS: A descriptive analysis was carried out on adverse events following immunization (AEFI) based on the administration of sIPV alone or concomitant with other vaccines (from 2015 to 2020) using data from the national AEFI surveillance system of China (CNAEFIS). All adverse reactions (ADRs) of the concomitant immunization were coded using a medical dictionary for regulatory activities (MedDRA) before comparison. RESULTS: The CNAEFIS reported a total of 9130 sIPV-related AEFI cases, including 6842 AEFI cases collected after immunization with sIPV alone and 2288 AEFI cases collected after immunization of sIPV concomitant with other vaccines. The combination of sIPV with diphtheria, tetanus and pertussis vaccine (DTaP) was correlated with the highest frequency of AEFI, which accounted for 53.50% of all 2288 AEFI cases. After MedDRA-based coding, the most frequent ADR was fever (70.18%), followed by erythema and swelling at the injection site (6.95%), induration at the injection site (3.85%), dermatitis allergy (3.56%) and urticaria (1.55%). A statistically significant difference (P < .001) was found between sIPV immunization and sIPV immunization concomitant with other vaccines for general reactions (95.36% and 93.22%, respectively) and abnormal reactions (4.64% and 6.78%, respectively). CONCLUSION: No new safety signal is found for sIPV administered concomitantly, although its administration with other vaccines may increase the occurrence of abnormal reactions. Vaccine manufacturers should focus on the safety of administering sIPV with DTaP and carry out relevant clinical studies when necessary.

Controllability of Graphene Oxide Doxorubicin Loading Capacity Based on Density Functional Theory.

Graphene can be used as a drug carrier of doxorubicin (DOX) to reduce the side effects of doxorubicin. However, there is limited research on the surface chemical modifications and biological effects of graphene oxide (GO). Therefore, it is necessary to explore the DOX affinity of different oxygen-containing functional groups in the graphene system. We constructed graphene system models and studied the structure and distribution of epoxy and hydroxyl groups on the carbon surface. Based on molecular dynamics simulations and density functional theory (DFT), we investigated the interaction between DOX and either pristine graphene or GO with different ratios of oxygen-containing groups. The hydroxyl groups exhibited a stronger affinity for DOX than the epoxy groups. Therefore, the DOX loading capacity of graphene systems can be adjusted by increasing the ratio of hydroxyl to epoxy groups on the carbon surface.

A Review of 3D Printing in Dentistry: Technologies, Affecting Factors, and Applications.

Three-dimensional (3D) printing technologies are advanced manufacturing technologies based on computer-aided design digital models to create personalized 3D objects automatically. They have been widely used in the industry, design, engineering, and manufacturing fields for nearly 30 years. Three-dimensional printing has many advantages in process engineering, with applications in dentistry ranging from the field of prosthodontics, oral and maxillofacial surgery, and oral implantology to orthodontics, endodontics, and periodontology. This review provides a practical and scientific overview of 3D printing technologies. First, it introduces current 3D printing technologies, including powder bed fusion, photopolymerization molding, and fused deposition modeling. Additionally, it introduces various factors affecting 3D printing metrics, such as mechanical properties and accuracy. The final section presents a summary of the clinical applications of 3D printing in dentistry, including manufacturing working models and main applications in the fields of prosthodontics, oral and maxillofacial surgery, and oral implantology. The 3D printing technologies have the advantages of high material utilization and the ability to manufacture a single complex geometry; nevertheless, they have the disadvantages of high cost and time-consuming postprocessing. The development of new materials and technologies will be the future trend of 3D printing in dentistry, and there is no denying that 3D printing will have a bright future.

Role of integrin­linked kinase in static compressive stress­induced autophagy via phosphatidylinositol 3 kinase in human periodontal ligament cells.

Orthodontic tooth movement (OTM) is achieved by using mechanical stimuli, which lead to the remodeling of periodontal tissues. Previous findings have demonstrated that autophagy may be one of the cell responses to mechanical stress. As a key structure in the integrin pathway, integrin linked­kinase (ILK) may play a role in the transmission of these mechanical signals. In addition, ILK is an important upstream molecule that regulates autophagy, under the influence of phosphatidylinositol 3 kinase (PI3K). Therefore, exploring the effect of mechanical stress on autophagy and the associated role of ILK/PI3K is of utmost significance to understanding the mechanism behind OTM. In the present study, human periodontal ligament cells (hPDLCs) were embedded into a collagen­alginate complex hydrogel for three­dimensional (3D) culturing. Static compressive stress (2.5 g/cm2) was loaded using the uniform weight method for 5, 15, 30, and 60 min. The autophagy of hPDLCs was detected by the expression of Beclin­1 (BECN1) and ATG­5 using RT­qPCR and LC3, respectively, using immunofluorescence. The results showed that the level of autophagy and gene expression of ILK increased significantly under static compressive stress. In ILK­silenced cells, static compressive stress could also upregulate ILK expression and increase the levels of autophagy. After PI3K inhibition, the increase in the autophagy level and the upregulation of ILK expression disappeared. These findings suggest that static compressive stress can induce autophagy in hPDLCs in a rapid, transient process, regulated by ILK and PI3K. Moreover, this static stress can upregulate ILK expression in a PI3K­dependent manner.

Energy release induced rockbursts based on butterfly-shaped plastic zones in roadways of coal reservoirs.

According to the theories of rockburst based on butterfly-shaped plastic zones, a plane strain mechanical model was established for stress distribution around the holes in homogeneous elastoplastic media. Based on the Mohr-Coulomb yield criterion and the generalized form of Hooke's law, the equation for the elastic strain-energy density of units at a 3D stress state was deduced. On this basis, the energy absorption and release in rocks surrounding a roadway during the evolution thereof in a coal reservoir tend to rock bursting were quantified. Through Flac3D 5.0 numerical simulation software, the energy released from a homogeneous circular roadway at different development states of plastic zones was investigated. By investigating conditions at the 21141 working face in Qianqiu Coal Mine, Henan Province, China, subjected to rockburst, a numerical model was established to calculate the energy released by a rockburst working face. The calculated results approximated the data monitored at the outburst site, with the same energy level recorded. The theoretical calculation for energy release from the rock surrounding a roadway is expected to reference engineering practice.

In Vivo Corrosion Behavior of Biodegradable Magnesium Alloy by MAF Treatment.

Coating treatment plays an irreplaceable role in propelling the clinical application of magnesium alloys. This experiment was designed in order to observe the anticorrosion behavior of magnesium fluoride coating in rats. The MgF2 layer was prepared on the surface of AZ31 magnesium alloy in saturated NH4HF2 solution by microarc fluorination (MAF) at 190 V. The cross-sectional SEM, EDS, and XRD analysis indicated that the alloy surface was covered with MgF2. Meanwhile, SEM observation was used to compare the magnesium alloy samples before and after treatment, and it was found that the samples after coating were flatter and smoother. Two sets of experiments were carried out with the subjects, 6-week-old male rats. So that the untreated AZ31 samples and the microarc fluorinated AZ31 samples could be buried under the muscle layer individually. The volume changes and surface morphology of the corroded samples were monitored dynamically using micro-CT over a 16-week period in vivo. Comparison of results between the two sets of samples presented that the corrosion of the microarc fluoridated samples was much slower than that of the untreated ones. The MAF coating was shown to be effective in controlling the corrosion rate and progression of the magnesium alloy.

Corrosion Evaluation of Pure Mg Coated by Fluorination in 0.1 M Fluoride Electrolyte.

In the ongoing research on the application of biodegradable materials, surface treatment of is considered to be a relatively effective solution to the excessive degradation rates of Mg alloys. In this study, to further optimize the proven effective surface coatings of fluoride, a low-voltage preparation fluorination method was used to achieve coating effectiveness under safer conditions. Optical observation, scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), and potential dynamic polarization (PDP) experiments were used for the analysis and evaluation. The coating characteristics of the MgF2 coatings treated in the 10-90 V voltage range, including the structure, chemical conformation, and electrochemical corrosion assessment, were fully defined. The anodic fluoridation results showed that a pore structure of 1-14 µm thickness was formed on the Mg alloy substrate, and the coating was composed of Mg fluoride. The results of immersion corrosion and electrochemical corrosion experiments showed that compared with pure Mg, anodic fluorinated samples below 40 V exhibited better corrosion resistance, the prepared MgF2 coating was more uniform, and the surface mostly exhibited point corrosion. When the voltage reached or exceeded 60 V, the prepared coating exhibited poor corrosion resistance, fracture, and protrusions. After corrosion, it mostly exhibited surface corrosion. The results indicate that idealized coatings can be obtained at relatively low and safe voltage ranges. This finding may enable more economical, environmentally friendly, and safe preparation of coatings.

Analysis of Three-Dimensional Morphological Differences in the Mandible between Skeletal Class I and Class II with CBCT Fixed-Point Measurement Method.

This study was aimed at determining the three-dimensional differences in the mandible morphology between skeletal class I and II patients, at exploring the pathogenic mechanisms and morphological characteristics of skeletal class II, and at providing clinical references. The subjects were assigned to two groups according to the size of ANB angle: skeletal class I (2° < ANB angle < 5°) and skeletal class II (5° < ANB angle < 8°). After cone-beam computed tomography (CBCT) scanning, 31 landmarks and 25 measurement items were determined by In Vivo Dental 5.1 software (Anatomage, CA) for statistical analysis. The results were as follows: Co-Go, Go-Me, and CdM-CdD in skeletal class II cases were smaller than those in skeletal class I, and GoR-Me-GoL, GoR-Me-CoL, and, Ig-Men were larger than those in skeletal class I cases. In conclusion, there were significant differences in the three-dimensional morphology of the mandible between skeletal class I and class II patients. The vertical growth of the ramus, the horizontal growth of the mandibular body, and the condyle in skeletal class II patients were smaller than those in skeletal class I cases. In skeletal class II, the growth of the anterior part of the mandible in the vertical direction was larger than that in skeletal class I, and the shape of the mandible was more extended.

Accuracy and Precision Evaluation of International Standard Spherical Model by Digital Dental Scanners.

With the popularization of digital technology and the exposure of traditional technology's defects, computer-aided design and computer-aided manufacturing (CAD/CAM) has been widely used in the field of dentistry. And the accuracy of the scanning system determines the ultimate accuracy of the prosthesis, which is a very important part of CAD/CAM, so we decided to evaluate the accuracy of the intraoral and extraoral scanners. In this study, we selected the sphere model as the scanning object and obtained the final result through data analysis and 3D fitting. In terms of trueness and precision, the scanner of SHINING was significantly different from that of others; however, there was no significant difference between TRIOS and CEREC. SHINING showed the lowest level of accuracy, with CEREC slightly lower than TRIOS. The sphere model has also been proven to be scanned successfully.

Habitual dietary calcium intakes and calcium metabolism in healthy adults Chinese: a systematic review and meta-analysis.

To investigate the metabolic differences of calcium requirements between Chinese and Westerners, we examined systematically the characteristics of calcium metabolism in Chinese adults with habitual dietary calcium intakes. We searched PubMed, Cochrane Library, SinoMed, and National Index to Chinese Newspapers & Periodicals, from inception to March 17, 2015, as well as the bibliographies of any relevant papers and journals, for trials assessing calcium metabolism in healthy Chinese adults within 18-60 years of age on the typical Chinese diet. We extracted a standardized dataset from metabolic studies that reported intake, retention, urinary excretion, faecal excretion and/or fractional absorption of calcium. We pooled data with a random effects meta-analysis. Of 2,046 citations identified by the search strategy, 12 studies (comprising 137 participants, 13 aggregate data deriving from 257 individual data) met the inclusion criteria. Metabolic data with self-chosen or typical Chinese diets were analyzed. Mean daily intakes of calcium ranged between 288 and 948 mg. Mean calcium retentions of each study were between 13 and 294 mg/d. The overall pooled value for dietary intake, urinary excretion, faecal excretion, retention and fractional absorption of calcium were 583 mg/d, 117 mg/d, 381 mg/d, 72 mg/d and 33.3%. Dietary calcium intake and faecal calcium excretion explained almost 85% of the heterogeneity of calcium retention. Chinese adults could maintain a positive calcium balance with plant-based diets at calcium intakes as low as 300 mg/d through increasing fractional calcium absorption and decreasing calcium excretion in urine and faeces.

Calcium requirements for Chinese adults by cross-sectional statistical analyses of calcium balance studies: an individual participant data and aggregate data meta-regression.

BACKGROUND: Chinese dietary reference intakes for calcium are largely based on foreign studies. We undertook meta-regression to estimate calcium requirements for Chinese adults derived from calcium balance data in Chinese adults. METHODS: We searched PubMed, Cochrane CENTRAL, and SinoMed from inception to March 5, 2014, by using a structured search strategy. The bibliographies of any relevant papers and journals were also screened for potentially eligible studies. We extracted a standardized data set from studies in Chinese adults that reported calcium balance data. The relationship between calcium intake and output was examined by an individual participant data (IPD) and aggregate data (AD) meta-regression. RESULTS: We identified 11 metabolic studies in Chinese adults within 18-60 years of age. One hundred and forty-one IPD (n = 35) expressed as mg/d, 127 IPD (n = 32) expressed as mg×kg body wt(-1)×d(-1), and 44 AD (n = 132) expressed as mg/d were collected. The models predicted a neutral calcium balance (defined as calcium output (Y) equal to calcium intake (C)) at intakes of 460 mg/d (Y = 0.60C+183.98) and 8.27 mg×kg body wt(-1)×d(-1) (Y = 0.60C+3.33) for IPD, or 409 mg/d (Y = 0.66C+139.00) for AD. Calcium requirements at upper intakes were higher than that at lower intakes in all these models. CONCLUSION: Calcium requirement for Chinese adults 18-60 years of age approximately ranges between 400 mg/d and 500 mg/d when consuming traditional plant-based Chinese diets.