Objective To evaluate the predictive value of different machine learning models constructed in a multicenter environment for potential organ donors and verify their clinical application feasibility. Methods The study included 2 000 inpatients admitted to five domestic tertiary hospitals from January 2020 to December 2023, who met the criteria for potential organ donation assessment. They were randomly divided into a training set and an internal validation set (7∶3). Another 300 similar patients admitted to the First Affiliated Hospital of Harbin Medical University from January 2024 to April 2025 were included as an external validation set. The area under the curve (AUC), sensitivity, specificity, accuracy and F1-score of three models were compared, and the consistency of the potential organ donor determination process was tested. Multivariate logistic regression analysis was used to identify predictive factors of potential organ donors. Decision curve analysis (DCA) was employed to verify the resource efficiency of each model, and the threshold interval and intervention balance point were assessed. Results Apart from age, there were no significant differences in other basic characteristics among the centers (all P>0.05). The consistency of the potential organ donor determination process among researchers in each center was good [all 95% confidence interval (CI) lower limits >0]. In the internal validation set, the XGBoost model had the best predictive performance (AUC=0.92, 95% CI 0.89-0.94) and the best calibration (P=0.441, Brier score 0.099). In the external validation set, the XGBoost model also had the best predictive performance (AUC=0.91, 95% CI 0.88-0.94), outperforming logistic regression and random forest models. Multivariate logistic regression showed that mechanical ventilation had the greatest impact (odds ratio=2.06, 95% CI 1.54-2.76, P<0.001). DCA indicated that the XGBoost model had the highest net benefit in the threshold interval of 0.2-0.6. The “treat all” strategy only had a slight advantage at extremely low thresholds. The recommended threshold interval, which balances intervention costs and clinical benefits, considers ≥50% positive predictive value (PPV) and ≤50 referrals per 100 high-risk patients. Conclusions The XGBoost model established in a multicenter environment is accurate and well-calibrated in predicting potential organ donors. Combined with DCA, it may effectively guide the timing of clinical interventions and resource allocation, providing new ideas for the assessment and management of organ donation after brain death.

Microglial functions are linked to Ca²⁺ signaling, with endoplasmic reticulum (ER) calcium stores playing a crucial role. Microglial abnormality is a hallmark of Alzheimer's disease (AD), but how ER Ca²⁺ receptors regulate microglial functions under physiological and AD conditions remains unclear. We found reduced ryanodine receptor 2 (Ryr2) expression in microglia from an AD mouse model. Modulation of RyR2 using S107, a RyR-Calstabin stabilizer, blunted spontaneous Ca²⁺ transients in controls and normalized Ca²⁺ transients in AD mice. S107 enhanced ATP-induced migration and phagocytosis while reducing ramification in control microglia; however, these effects were absent in AD microglia. Our findings indicate that RyR2 stabilization promotes an activation state shift in control microglia, a mechanism impaired in AD. These results highlight the role of ER Ca²⁺ receptors in both homeostatic and AD microglia, providing insights into microglial Ca²⁺ malfunctions in AD.
Animals ; Microglia/pathology* ; Alzheimer Disease/pathology* ; Phagocytosis/drug effects* ; Ryanodine Receptor Calcium Release Channel/metabolism* ; Disease Models, Animal ; Mice ; Cell Movement/drug effects* ; Mice, Transgenic ; Calcium Signaling/physiology* ; Calcium/metabolism* ; Mice, Inbred C57BL ; Male ; Endoplasmic Reticulum/metabolism*

Objective: To study the effect of a space stabilizing device on the capacity for osteogenesis in the bone-grafted area. Methods: Patients with anterior teeth defects as well as labial alveolar ridge defects were randomly divided into two groups: the experimental group was treated using a space stabilization device after guided bone regeneration whereas the control group received regular guided bone regeneration. The CBCT data was analyzed prior to, immediately and 6 months after procedure to compare the osteogenesis with or without the device. Results: Seventeen bone-grafted sites were examined(7 in the experimental group and 10 in the control group). At 2 mm and 4 mm below the alveolar ridge, the horizontal bone resorption rate in the experimental group was significantly lower than the corresponding level in the control group(P=0.001). The horizontal bone resorption rate at 2 mm below the alveolar ridge of each group was significantly higher than that at 4 mm below the alveolar ridge in corresponding groups(P=0.003). Conclusion The space stabilizing device used in this study has a positive clinical impact on preserving space stability and minimizing bone resorption.

Objective:To explore the application effect and evaluation of virtual reality technology in oral implant therapy training.Methods:In November 2018, one adult patient (female, 36 years old) with missing right mandibular first molar was treated in the Department of Implantology, School and Hospital of Stomatology, Fujian Medical University. The three-dimensional virtual models of mandible and implant surgery tools were established, and the virtual reality software (Unity 3D 5.5.1) was imported. Combined with the virtual reality head mounted display, a virtual reality training system simulating the dental implant treatment process was independently developed. Ten refresher doctors and 20 graduate students in Department of Implantology, School and Hospital of Stomatology, Fujian Medical University from September 2018 to December 2019 were recruited as the experimental objects (no clinical experience was found). According to the level and seniority of doctors, they were randomly divided into virtual training group and conventional training control group, which made the two groups comparable, with 15 in each group. Subjective scores (including anatomical structure, surgical field of vision, cavity preparation, implant placement and process mastery) were given after the corresponding training in the two groups, and the virtual reality training system was used to test. The mesial and distal direction, buccolingual direction, depth and angle deviation of implants before and after the training were analyzed, and the differences between the two groups were compared.Results:The subjective scores of five dimensions in the virtual training group were significantly higher than those in the conventional training control group ( P<0.05). In the virtual training group, the mesial and distal, buccolingual, depth and angle deviation of implants were (0.73±0.33), (0.78±0.41), (0.61±0.32) mm and 6.66°±3.87°. All of them were significantly lower than those in the control group [(0.85±0.32), (1.12±0.38), (0.89±0.24) mm and 9.68°±3.74°] ( P<0.05). Conclusions:The self-developed virtual reality system of oral implant has good application effect, good operability and predictability. It can be effectively carried out in implant education and training, and it can strengthen skills of doctors, and is conducive to the practical operation.

Objective To explore the role and mechanism of tumor necrosis factor ligand -related molecule 1A (TL1A) in chronic experimental colitis associated intestinal fibrosis .Methods The model of chronic experimental colitis-associated intestinal fibrosis was induced by dextran sodium sulfate (DSS).The mice with high TL1A (L-Tg) expression in lymphoid cells and wild -type mice with the same genetic background were divided into wild type control group, wild type DSS group, transgenic control group and transgenic DSS group.The changes of body mass, length of colon, disease activity index (DAI) and colonic pathological score were compared among different groups .The degree of colonic inflammation was evaluated by Hematoxylin -Eosin (H-E) staining.The degree of intestinal fibrosis was assessed by Masson staining and Sirius red staining .The expression of vimentin, αsmooth muscle actin ( α-SMA), type Ⅰ collagen, Ⅲ collagen and transforming growth factor-β1 ( TGF-β1 ) /Smad3 in colon tissue was examined by immunohistochemistry .T test was performed for statistical analysis.Results The body mass of the transgenic DSS group decreased by (9.6 ± 1.8)％, which was more than wild-type DSS group (6.2 ±1.3)％, the difference was statistically significant (t =3.751, P <0.01).The DAI score and colonic pathological score of transgenic DSS group were both higher than those of wild-type DSS group (7.33 ±0.58 vs.6.00 ±1.00, and 14.00 ±1.05 vs.11.75 ±0.50, respectively), and the differences were statistically significant (t =2.818 and 4.739, both P <0.05).The results of Masson staining and Sirius red staining showed aggravation of intestinal fibrosis .The results of immunohistochemical staining showed that the cumulative positive absorbance values of vimentin , α-SMA, TGF-β1 and Smad3 of wild-type DSS group were lower than those of transgenic DSS group (0.650 ±0.050 vs. 0.800 ±0.020, 0.390 ±0.040 vs.0.600 ±0.040, 0.550 ±0.040 vs.0.730 ±0.040, 0.590 ±0.020 vs. 0.830 ±0.040), and the differences were statistically significant (t =6.823, 9.093, 7.794 and 10.390, all P <0.01).Conclusion TL1A may promote the proliferation and activation of fibroblasts through TGF -β1 /Smad3 pathway, leading to the genesis and development of experimental colitis associated intestinal fibrosis .

Objective To screen the dual oxidase maturation factor 1 (DUOXA1) gene mutations in children with congenital hypothyroidism (CH) and thyroid goiter from Shandong Province,China,and to identify the gene mutation type and characteristics of DUOXA1 gene mutations in order to provide some evidence for gene diagnosis and therapy of CH.Methods A cohort of 52 cases of CH with thyroid goiter and 100 normal controls were selected according to neonatal screening system in Shandong Province whose genomic DNA was isolated from peripheral blood leukocytes with a standard phenol chloroform method.The whole coding sequence (CDS) of DUOXA1 gene was amplified with 8 pairs of sequence specific primers by using PCR.The PCR products were directly sequenced with Sanger sequencing to detect new mutations types of DUOXA1 gene.The sequencing data were compared to the DUOXA1 gene reference sequence(National Center for Biotechnology Information:RefSeq:NG_033105.1) to see if there was any mutation.Ax2 test was done for the gene frequency of discovered single nucleotide polymorphisms (SNP).Results There was no mutation in CDS of 52 CH patients with thyroid goiter and 100 normal controls.However,a SNP (rs75981505,c.398G ＞ T) which was an missense mutation and could lead to a change of the codon from CGC to CTC,was found in 9 CH patients with thyroid goiter and 11 normal controls in the exon 7.The corresponding amino acid arginine was replaced by histidine(p.Arg133His).There was no significant difference in the SNP rate between CH patients with thyroid goiter and normal controls (17.3％ vs 11.0％,x2 =1.24,P ＞ 0.05).Conclusion DUOXA1 gene mutation rate is very low which may not be the main cause of CH patients with thyroid goiter in the population of Shandong Province.

From the perspective of portable monitoring devices,we use an analog front-end AFE4490 design a module of Non-invasive blood oxygen measurement, used to collect human pulse wave signal and peak (valley) value detection and then use the principles of non-invasive oximetry calculated oxygen saturation (SPO2). This design of noninvasive oximetry module has the characteristics of small size, low power consumption, and the results of test show that the measurement of oxygen saturation are correct.
Heart Rate ; Humans ; Oximetry ; instrumentation ; methods ; Oxygen ; blood

From the perspective of portable monitoring devices,we use an analog front-end AFE4490 design a module of Non-invasive blood oxygen measurement,used to colect human pulse wave signal and peak (valey) value detection and then use the principles of non-invasive oximetry calculated oxygen saturation (SPO2). This design of noninvasive oximetry module has the characteristics of smal size, low power consumption, and the results of test show that the measurement of oxygen saturation are correct.

BACKGROUND:Previous researches have focused on the effect of phosphorus compounds on stem cels from animals or from human. But there is no study on the effect of phosphorus ions on human bone marrow mesenchymal stem cels under three-dimensional culture. OBJECTIVE:To explore the effect of phosphorus ions on human bone marrow mesenchymal stem cels under three-dimensional culture. METHODS:There were six groups in the experiment. Human bone marrow mesenchymal stem cels were inoculated in three-dimensional polystyrene scaffolds and then subjected to serum-free growth medium (group 3-GM) or serum-free growth medium containing 4 mmol/L (group 3-4P), 8 mmol/L (group 3-8P) phosphorus ions for 21 days, respectively. Cels cultured on the two-dimensional polystyrene scaffolds were used as control groups (groups 2-GM, 2-4P, 2-8P). Celular proliferation was examined by cel counting kit-8; the mRNA expressions of osteogenic marker genes were assessed by RT-PCR; the formation of mineralized nodules for the osteogenic differentiation of human bone marrow mesenchymal stem cels was examined by Alizarin red staining. RESULTS AND CONCLUSION:Compared with the two-dimensional culture, the growth of human bone marrow mesenchymal stem cels induced by phosphorus ions were more obvious in the three-dimensional polystyrenes scaffolds at days 4, 7, 14 and 21 (P < 0.05). Compared with the group 3-GM, the mRNA expression of colagen type I in groups 3-4P and 3-8P increased more significantly at days 7 and 14 (P < 0.05); the mRNA expression of alkaline phosphatase in groups 3-4P and 3-8P increased more significantly at day 14 (P < 0.05); the mRNA expression of osteocalcin in groups 3-4P and 3-8P increased more significantly at days 14 and 21 (P < 0.05). Mineralized nodules were formed in groups 3-4P and 3-8P but not in group 3-GM at day 21. So we concluded that phosphorus ions can promote proliferation and osteogenic differentiation of human bone marrow mesenchymal stem cels in three-dimensional polystyrenes scaffolds. Compared with the two-dimensional cel culture, the promoting growth effect of phosphorus ions on human bone marrow mesenchymal stem cels in three dimensional polystyrenes scaffolds are more obvious.

Objective To observe the effects of treadmill training on hindlimb motor recovery and noradrenaline (NA) fibers in rats with spinal cord contusion.MethodsSpinal cord contusions at the T10 level were induced in 3-month old female SD rats by dropping a 10 g rod from a height of 25 mm.The injured rats were then randomly divided into a control group and a treadmill training group ( n =15 in each group).Treadmill training began 1 week post-injury.No treatment was administered to the control group rats.Hindlimb motor function was evaluated weekly from the 1 st to the 9th week post-injury using Basso Beattie Bresnahan (BBB) scores and average combined scores (ACOs).The expression of dopamine beta hydroxylase (DBH) in the spinal cord caudal to the injured area was detected by immunohistochemical staining.ResultsThe treadmill training group exhibited significantly greater improvement in BBB scores from the 3rd week to the 7th week and in ACOs from the 2nd to the 9th week post-injury compared with the control group.The number of DBH positive fibers in the injured spinal cords and the number of DBH positive neurons in the injured frontal horns were also significantly higher in the training group.ConclusionsTreadmill training can promote the recovery of hindlimb motor function in rats after spinal cord contusion,perhaps by increasing the number of DBH positive fibers and DBH positive neurons.