Objective: To explore the efficacy of a novel injectable hydrogel (GelMA/P11/IL4@LIP) loaded with P11 bacteriophages and interleukin-4 (IL-4) liposomes (LIP) in preventing relapse after maxillary expansion in mice, providing experimental evidence for its clinical application. Methods: This study was approved by the experimental animal ethics committee of our hospital. First, 15 7-week-old C57BL/6 mice were used to establish a maxillary expansion model and divided into 5 groups (3 mice in each group): a control group, post expansion day 3 group (PED3 group), post expansion day 7 group (PED7 group), retention for 14 days group (RET group), and relapse for 7 days group (REL group). The mice in each group were sacrificed at their designated time points (day 0, 3, 7, 21, 28), and their maxilla and anterior cranial regions were collected. Bone parameters and the inter-crestal distance (ICD) of maxillary incisor mesial alveolar ridge were measured using micro-computed tomography (micro-CT). Histological staining was performed to evaluate bone formation and resorption, while immunohistochemistry (IHC) was performed for macrophage markers (CD86 and CD206), mesenchymal stem cell markers (glioma-associated oncogene homolog 1 [Gli1]), and osteogenic markers (Runt-related transcription factor 2 [Runx2] and Osterix [OSX]). Next, GelMA/P11/IL4@LIP was synthesized and administered to mouse models of maxillary expansion. A total of 24 7-week-old C57BL/6 mice were divided into 4 groups (6 mice in each group): a blank control group, GelMA group, GelMA/P11 group, and GelMA/P11/IL4@LIP group. All mice underwent palatal expansion. On PED7, the expanders of all 24 mice were cemented with resin to initiate the 14-day retention period. On day 1 of the retention phase, the mice in each group received injections of saline, GelMA, GelMA/P11, or GelMA/P11/IL4@LIP at the midpalatal suture. After the 14-day retention period, three mice in each group were randomly selected and sacrificed, while the other three had their expanders removed and underwent a 7-day relapse before being sacrificed on day 28 (REL). Micro-CT, histological staining, and IHC were performed to evaluate the preventive effect of GelMA/P11/IL4@LIP on post-expansion relapse. Results: The mice maxillary expansion model exhibited a decreased ICD at REL compared to RET in micro-CT analysis (P = 0.008). IHC analysis demonstrated prolonged M1 macrophage infiltration, scarce Gli1+ mesenchymal stem cells, and insufficient expression of osteogenic markers (RUNX2 and OSX) (P < 0.001). Compared to the blank control and GelMA groups, GelMA/P11/IL4@LIP hydrogel injection in the midpalatal suture led to increased ICD at REL, promoted the timely M2 polarization of macrophages, recruited Gli1+ mesenchymal stem cells, and upregulated the expression of RUNX2 and OSX (P < 0.05). Conclusion The mechanism of relapse after maxillary expansion involves the persistent infiltration of M1 macrophages, as well as the inadequate recruitment and insufficient osteogenic differentiation of MSCs in the midpalatal suture. The GelMA/P11/IL4@LIP composite enhanced orofacial mesenchymal stem cell recruitment and promoted the M2 polarization of macrophages, thereby enhancing osteogenesis in the midpalatal suture and preventing post-expansion relapse.

BACKGROUND:Previous studies by the research team have shown that the neuroprotective effect of ginsenoside Rb1 on improving cerebral ischemia-reperfusion injury may be related to the Wnt/β-catenin signaling pathway,but the specific mechanism of action remains unclear.OBJECTIVE:To explore the molecular mechanism of ginsenoside Rb1 in alleviating cerebral ischemia-reperfusion injury in mice.METHODS:100 C57BL/6 mice were randomly divided into four groups.The sham operation group(n=25)did not undergo model establishment.In the cerebral ischemia-reperfusion injury group(n=25),the middle cerebral artery occlusion model was established by thread embolism.In the ginsenoside Rb1 group(n=25),the middle cerebral artery occlusion model was established by thread embolism and ginsenoside Rb1 was intraperitoneally injected every day for 3 days before the establishment.In ginsenoside Rb1+inhibitor group(n=25),the middle cerebral artery occlusion model was established by thread embolism and ginsenoside Rb1 and Wnt/β-catenin signaling pathway inhibitor XAV939 were intraperitoneally injected every day for 3 days before the establishment.Three days after modeling,Zea Longa score and balance beam test were used to evaluate the neurological deficits of mice.TTC staining was used to observe the volume of cerebral infarction.The dry-wet mass method was used to detect the degree of brain edema in mice.The activities of superoxide dismutase and glutathione peroxidase and the concentration of malondialdehyde in the parietal lobe of the ischemic side were detected by colorimetry.The co-expression of microglial marker Iba1 and inducible nitric oxide synthase(or arginase 1)was detected by immunofluorescence.The levels of aquaporin AQP4,inflammatory-related factors,and phosphorylation of Wnt/β-catenin pathway proteins glycogen synthase kinase 3β and β-catenin were detected by western blot assay.The mRNA expression of inflammatory factors was detected by q-PCR.RESULTS AND CONCLUSION:(1)Compared with cerebral ischemia-reperfusion injury group,the neurological deficit symptoms,cerebral infarction foci and brain tissue edema,oxidative stress and inflammatory response of the mice were alleviated;the number of M1 microglia(Iba1 and inducible nitric oxide synthase co-expressed)decreased;the number of M2 microglia(Iba1 and arginase 1 co-expressed)increased;the expression of phosphorylated glycogen synthase kinase 3β and phosphorylated β-catenin protein decreased in ginsenoside Rb1 group.Compared with ginsenoside Rb1 group,the neurological deficit symptoms,cerebral infarction foci and brain tissue edema,oxidative stress and inflammatory response of the mice were aggravated;the number of M1 microglia increased;the number of M2 microglia decreased;the expression of phosphorylated glycogen synthase kinase 3β and phosphorylated β-catenin protein increased in ginsenoside Rb1+inhibitor group.(2)The results indicate that ginsenoside Rb1 can regulate the polarization of microglia to M2 type and alleviate oxidative stress damage and inflammatory response after cerebral ischemia-reperfusion injury.Its mechanism may be related to the nuclear translocation of β-catenin mediated by the Wnt/β-catenin signaling pathway.

BACKGROUND:Previous studies by the research team have shown that the neuroprotective effect of ginsenoside Rb1 on improving cerebral ischemia-reperfusion injury may be related to the Wnt/β-catenin signaling pathway,but the specific mechanism of action remains unclear.OBJECTIVE:To explore the molecular mechanism of ginsenoside Rb1 in alleviating cerebral ischemia-reperfusion injury in mice.METHODS:100 C57BL/6 mice were randomly divided into four groups.The sham operation group(n=25)did not undergo model establishment.In the cerebral ischemia-reperfusion injury group(n=25),the middle cerebral artery occlusion model was established by thread embolism.In the ginsenoside Rb1 group(n=25),the middle cerebral artery occlusion model was established by thread embolism and ginsenoside Rb1 was intraperitoneally injected every day for 3 days before the establishment.In ginsenoside Rb1+inhibitor group(n=25),the middle cerebral artery occlusion model was established by thread embolism and ginsenoside Rb1 and Wnt/β-catenin signaling pathway inhibitor XAV939 were intraperitoneally injected every day for 3 days before the establishment.Three days after modeling,Zea Longa score and balance beam test were used to evaluate the neurological deficits of mice.TTC staining was used to observe the volume of cerebral infarction.The dry-wet mass method was used to detect the degree of brain edema in mice.The activities of superoxide dismutase and glutathione peroxidase and the concentration of malondialdehyde in the parietal lobe of the ischemic side were detected by colorimetry.The co-expression of microglial marker Iba1 and inducible nitric oxide synthase(or arginase 1)was detected by immunofluorescence.The levels of aquaporin AQP4,inflammatory-related factors,and phosphorylation of Wnt/β-catenin pathway proteins glycogen synthase kinase 3β and β-catenin were detected by western blot assay.The mRNA expression of inflammatory factors was detected by q-PCR.RESULTS AND CONCLUSION:(1)Compared with cerebral ischemia-reperfusion injury group,the neurological deficit symptoms,cerebral infarction foci and brain tissue edema,oxidative stress and inflammatory response of the mice were alleviated;the number of M1 microglia(Iba1 and inducible nitric oxide synthase co-expressed)decreased;the number of M2 microglia(Iba1 and arginase 1 co-expressed)increased;the expression of phosphorylated glycogen synthase kinase 3β and phosphorylated β-catenin protein decreased in ginsenoside Rb1 group.Compared with ginsenoside Rb1 group,the neurological deficit symptoms,cerebral infarction foci and brain tissue edema,oxidative stress and inflammatory response of the mice were aggravated;the number of M1 microglia increased;the number of M2 microglia decreased;the expression of phosphorylated glycogen synthase kinase 3β and phosphorylated β-catenin protein increased in ginsenoside Rb1+inhibitor group.(2)The results indicate that ginsenoside Rb1 can regulate the polarization of microglia to M2 type and alleviate oxidative stress damage and inflammatory response after cerebral ischemia-reperfusion injury.Its mechanism may be related to the nuclear translocation of β-catenin mediated by the Wnt/β-catenin signaling pathway.

Background The burden of chronic kidney diseases (CKD) is continuously increasing in the globe. Environmental factors are one of the trigger factors for chronic kidney diseases of unknown etiology (CKDu). However, the current toxicological evidence on the renal effects induced by environmental high concentrations of multiple ions in drinking water and high temperature exposure is very limited. Objective To preliminary investigate the renal effects of exposure to drinking water with environmental high concentrations of fluoride, calcium, sodium, and bromide ions alone or in combination with high temperature in mice. Methods A mouse drinking water exposure model was established using ICR male mouse (8 weeks old) with exposure to 3 mg·L⁻¹ fluoride ions, 250 mg·L⁻¹ calcium ions, 400 mg·L⁻¹ sodium ions, and 1 mg·L⁻¹ bromide ions (to mimic the high concentration of ions in the groundwater in the areas with a high prevalence rate of CKDu in Sri Lanka) and high temperature of 32 ℃. ICR male mice were randomly divided into a mixed fluoride-calcium-sodium-bromide ion and high temperature exposure group, exposure groups of each ion and high temperature alone, a fluoride-calcium-sodium ion exposure group, and a fluoride-calcium-sodium-bromide ion exposure group. In the control group, the animals were given normal purified water at room temperature of (23±2) ℃. After 12 consecutive weeks of exposure, body weights and liver (kidney) organ coefficients were determined. Assessment of renal histopathologic damage was performed by hematoxylin-eosin staining and pathology scoring. At the end of the 12-week exposure period, 24 h urine samples were collected for the measurements of creatinine (UCr), albumin (ALB), neutrophil gelatinase-associated lipocalin (NGAL), and β2-microglobulin (β2-MG) levels. Cell apoptosis was assessed by TUNEL assay. Results The mice in the mixed exposure group showed a significant decrease in body weight and marked increases in the scores of renal histopathological injuries and the urinary levels of β2-MG compared to those of the control mice (P<0.05). Compared with the control group, the differences in body weight and urinary renal injury indexes of the mice in the fluoride-calcium-sodium and the fluoride-calcium-sodium-bromide ion groups (except for the decrease of the β2-MG levels in urinary in the latter group) were not statistically significant (P>0.05), but the renal histopathological injury scores were significantly increased (P<0.05). By contrast, body weights, liver (kidney) organ coefficient, and renal histopathological injury scores were comparable in the control mice and the mice fed with drinking water containing high levels of a single ion alone or housed at high temperature alone (P>0.05). Furthermore, the renal histopathological injury score showed no significant differences between the fluoride-calcium-sodium ion exposure group and the fluoride-calcium-sodium-bromide ion exposure group (P>0.05). The interaction between bromide ions and fluoride-calcium-sodium ions on renal tissue pathological damage was not statistically significant (P>0.05). Results from the TUNEL assay showed a significant increase in renal cell apoptosis in the fluoride-calcium-sodium ion exposure group (P<0.05). Conclusions Environmental high levels of mixed fluoride, calcium, and sodium ions in drinking water induce renal pathological damage in mice, which are exacerbated in combination with high temperature environment. High temperature exposure alone does not affect the pathological damage of renal tissue,

Objective:To evaluate the effectiveness for vital pulpotomy in primary teeth with 4 kinds of pulp capping agents.Methods:CHI,CH,GA and FC were chosen as the pulp capping agents for vital pulpotomy in primary teeth and 3 year follow up observation was performed.The teeth in other side served as the controls.The root absorption was observed radiologically.Results:In the group of CHI,CH,GA and FC the clinical effective rate were 100%,87.5%,91.4% and 78.1%,the radiographical success rate were 97%,60%,74.3%and 56.2%,respectively.In the cases treated with CHI showed the highest success rate and significant difference was found among the four groups (P