Objective To explore the application value of iASSIST portable navigation in total knee arthroplasty.Methods Seventy-four patients with knee osteoarthritis from April 2016 to April 2017 were retrospectively recruited.Thirty-seven patients (37 knees) underwent TKA with iASSIST navigation,while 37 patients (37 knees) underwent conventional TKA.Five parameters were measured on the weight-bearing radiographs at six months after TKA,including mechanical axis (MA),mechanical lateral distal femoral angle (mLDFA),mechanical medial proximal tibial angle (mMPTA),sagittal femoral component angle (sFCA) and sagittal tibial component angle (sTCA).Duration of operation,blood loss volume,postoperative hospital day,Western Ontario and McMaster Universities (WOMAC) osteoarthritis index,Knee Society Score (KSS) clinical score and functional score at 6 weeks,12 weeks and 24 weeks after surgery were also recorded.Results The accuracy of MA (180.85°±0.88° versus 182.23°±1.09° in the conventional group,P＜0.05),mLDFA (90.52° ±0.78° versus 91.09° ±0.96° in the conventional group,P＜0.05),and mMPTA (90.34°± 1.25° versus 91.13°± 1.46° in the conventional group,P＜0.05) was improved significantly in navigation group.The WOMAC osteoarthritis index at 6 weeks postoperatively in the navigation group and in the conventional group were 58.54±1.45 and 56.54± 1.77 respectively.The KSS clinical score in the navigation group and in the conventional group were 53.14± 1.13 and 49.35± 1.11 respectively.The KSS functional score in two groups were 61.24± 1.30 and 59.81 ± 1.29 respectively (P＜0.05).The WOMAC osteoarthritis index at 12 weeks postoperatively in the navigation group and in the conventional group were 43.54± 1.19 and 41.92± 1.42 respectively.At 12 weeks,the KSS clinical score in two groups were 67.11 ± 1.51 and 62.08± 1.46 respectively.The KSS functional score in two groups were 68.14±1.11 and 66.38±1.26 respectively (P＜0.05).The blood loss volume in the navigation group and in the conventional group were 113.11±57.29 ml and 147.57±68.77 ml respectively (P＜0.05).There were no significant difference in the duration of operation,postoperative hospital day,WOMAC osteoarthritis index,knee clinical score and functional score at 24 weeks postoperatively between two groups (P＞0.05).Conclusion More accurate restoration in mechanical axis and optimal implantation can be achieved with the help of iASSIST navigation.This navigation system can also achieve better knee function in the early stage after TKA.

Objective To assess the effect of ascorbic acid/ferric chloride (AA/FeCl3) in attenuating cartilage damage in rats with osteoarthritis. Methods Thirty adult male Wistar rats with surgically induced osteoarthritis were randomized into 2 groups for treatment with intra-articular injection of saline (control group) or AA/FeCl3 mixture (AA group) once a week starting from the third week after the operation. At 6, 9, and 12 weeks after the operation, 5 rats from each group were sacrificed for observing subchondral bone changes on X-ray films and evaluation of cartilage degeneration in the right knee joints using safranin-O/Fast green staining and a modified OARSI scoring system. The degradation of the cartilage matrix was observed by immunohistochemical staining for type II collagen. Results X-ray examination in saline control group revealed the presence of osteophytes and narrowing of the joint space at 9 weeks, and the joint line disappeared at 12 weeks after the surgery; only slight irregularity of the articular surface was observed in the AA group at 9 and 12 weeks. OARSI scores were significantly lower in AA group than in the control group at 9 weeks (18.67 ± 0.67 vs 12.17 ± 2.75;P<0.05) and 12 weeks (20.11 ± 1.84 vs 13.77 ± 0.40;P<0.05) but not at 6 weeks after the surgery. The content of type 2 collagen in AA group was significantly higher than that in the control group at 6 weeks (0.36 ± 0.039 vs 0.49 ± 0.029;P<0.05) and 9 weeks after the surgery (0.25 ± 0.041 vs 0.38 ± 0.040;P<0.05). Conclusions Early intra-articular injection of AA/FeCl3 can effectively delay the progression of post-traumatic osteoarthritis in rats.

Objective To explore the role of zinc finger protein 36 (ZFP36) in regulating osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) and preosteoblasts. Methods ZFP36 expression was observed in primary mouse BMSCs and mouse preosteoblasts (MC3T3-E1 cells) during induced osteogenic differentiation. Zfp36-deficient cell models were constructed in the two cells using RNA interference technique and the changes in differentiation capacities of the transfected cells into osteoblasts were observed. Transcriptome sequencing was used to investigate the potential mechanisms of ZFP36 for regulating osteoblast differentiation of the two cells. U0126, a ERK/MAPK signal suppressor, was used to verify the regulatory mechanism of Zfp36 in osteogenic differentiation of Zfp36-deficient cells. Results During the 14-day induction of osteogenic differentiation, both mouse BMSCs and MC3T3-E1 cells exhibited increased expression of ZFP36, and its mRNA expression reached the peak level on Day 7 (P<0.0001). The Zfp36-deficient cell models showed reduced intensity of alkaline phosphatase (ALP) staining and alizarin red staining with significantly lowered expressions of the osteogenic marker genes including Alpl, Sp7, Bglap and Ibsp (P<0.01). Transcriptome sequencing verified the reduction of bone mineralization-related gene expressions in Zfp36-deficient cells and indicated the involvement of ERK signaling in the potential regulatory mechanism of Zfp36. Immunoblotting showed that pERK protein expression increased significantly in Zfp36-deficient cells compared with the control cells. In Zfp36-deficient MC3T3-E1 cells, inhibition of activated ERK/MAPK signaling with U0126 resulted in obviously enhanced ALP staining and significantly increased expressions of osteoblast differentiation markers Runx2 and Bglap (P<0.05). Conclusions ZFP36 is involved in the regulation of osteoblast differentiation of mouse BMSCs and preosteoblasts, and ZFP36 deficiency causes inhibition of osteoblast differentiation of the cells by activating the ERK/MAPK signaling pathway.

Objective To assess the effect of ascorbic acid/ferric chloride (AA/FeCl3) in attenuating cartilage damage in rats with osteoarthritis. Methods Thirty adult male Wistar rats with surgically induced osteoarthritis were randomized into 2 groups for treatment with intra-articular injection of saline (control group) or AA/FeCl3 mixture (AA group) once a week starting from the third week after the operation. At 6, 9, and 12 weeks after the operation, 5 rats from each group were sacrificed for observing subchondral bone changes on X-ray films and evaluation of cartilage degeneration in the right knee joints using safranin-O/Fast green staining and a modified OARSI scoring system. The degradation of the cartilage matrix was observed by immunohistochemical staining for type II collagen. Results X-ray examination in saline control group revealed the presence of osteophytes and narrowing of the joint space at 9 weeks, and the joint line disappeared at 12 weeks after the surgery; only slight irregularity of the articular surface was observed in the AA group at 9 and 12 weeks. OARSI scores were significantly lower in AA group than in the control group at 9 weeks (18.67 ± 0.67 vs 12.17 ± 2.75;P<0.05) and 12 weeks (20.11 ± 1.84 vs 13.77 ± 0.40;P<0.05) but not at 6 weeks after the surgery. The content of type 2 collagen in AA group was significantly higher than that in the control group at 6 weeks (0.36 ± 0.039 vs 0.49 ± 0.029;P<0.05) and 9 weeks after the surgery (0.25 ± 0.041 vs 0.38 ± 0.040;P<0.05). Conclusions Early intra-articular injection of AA/FeCl3 can effectively delay the progression of post-traumatic osteoarthritis in rats.

Objective To explore the role of zinc finger protein 36 (ZFP36) in regulating osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) and preosteoblasts. Methods ZFP36 expression was observed in primary mouse BMSCs and mouse preosteoblasts (MC3T3-E1 cells) during induced osteogenic differentiation. Zfp36-deficient cell models were constructed in the two cells using RNA interference technique and the changes in differentiation capacities of the transfected cells into osteoblasts were observed. Transcriptome sequencing was used to investigate the potential mechanisms of ZFP36 for regulating osteoblast differentiation of the two cells. U0126, a ERK/MAPK signal suppressor, was used to verify the regulatory mechanism of Zfp36 in osteogenic differentiation of Zfp36-deficient cells. Results During the 14-day induction of osteogenic differentiation, both mouse BMSCs and MC3T3-E1 cells exhibited increased expression of ZFP36, and its mRNA expression reached the peak level on Day 7 (P<0.0001). The Zfp36-deficient cell models showed reduced intensity of alkaline phosphatase (ALP) staining and alizarin red staining with significantly lowered expressions of the osteogenic marker genes including Alpl, Sp7, Bglap and Ibsp (P<0.01). Transcriptome sequencing verified the reduction of bone mineralization-related gene expressions in Zfp36-deficient cells and indicated the involvement of ERK signaling in the potential regulatory mechanism of Zfp36. Immunoblotting showed that pERK protein expression increased significantly in Zfp36-deficient cells compared with the control cells. In Zfp36-deficient MC3T3-E1 cells, inhibition of activated ERK/MAPK signaling with U0126 resulted in obviously enhanced ALP staining and significantly increased expressions of osteoblast differentiation markers Runx2 and Bglap (P<0.05). Conclusions ZFP36 is involved in the regulation of osteoblast differentiation of mouse BMSCs and preosteoblasts, and ZFP36 deficiency causes inhibition of osteoblast differentiation of the cells by activating the ERK/MAPK signaling pathway.

Most organisms contain glutamate dehydrogenase (E.C. 1.4.1.2-1.4.1.4). In eukaryotes, the enzyme is mainly present in mitochondria. This enzyme plays a vital role in the metabolism of nitrogen and carbon and the signaling pathway. Studies have found that glutamate dehydrogenase has a certain relationship with the occurrence and development of tumors, which is significant for tumor research, but reviews on its relationship with human tumors are rare. This review summarized the relationship between glutamate dehydrogenase and breast cancer, glioma, colorectal cancer and ovarian cancer, etc, thus providing assistance for related research.
Carbon ; Glioma ; Glutamate Dehydrogenase ; Humans ; Mitochondria ; Nitrogen

In the field of dental aesthetics,digital aesthetic design plays a crucial role in helping dentists to predict treatment outcomes vis-ually,as well as in enhancing the consistency of knowledge and understanding of aesthetic goals between dentists and patients.It serves as the foundation for achieving ideal aesthetic effects.However,there is no clear standard for this digital process currently in China and abroad.Many dentists lack of systematic understanding of how to carry out digital aesthetic design for treatment.To establish standardized processes for dental aesthetic design and to improve the homogeneity of treatment outcomes,Chinese Society of Digital Dental Industry(CSD-DI)convened domestic experts in related field to compile this consensus.This article elaborates on the key aspects of digital aesthetic data collection,integration steps,and the digital aesthetic design process.It also formulates a decision tree for dental aesthetics at macro level and outlines corresponding workflows for various clinical scenarios,serving as a reference for clinicians.

OBJECTIVE: To optimize the method for embedding multiple undecalcified mouse tibias in plastic blocks, improve the efficiency and stability of plastic embedding and reduce the detachment rate of plastic slides. METHODS: Thirty undecalcified tibias from 15 B6 mice were used for plastic embedding after calcein labeling, fixation, dehydration and infiltration. The tibias were embedded in cylindrical plastic blocks with a diameter of 4 mm. For each bone, the 1/4 proximal tibia was cut off, and the remaining 3/4 was used for re-embedding. Five bones were embedded in a single block with each bone standing closely on the surface of a flat plate. The samples were randomized into control and experimental groups in all the processes of embedding, sectioning and staining. In the 3 groups with modified embedment, flowing CO was added into the embedding solution, embedding solution was applied to the section surface, and the slides were heated at 95 ℃ for 15 min. The polymerization time, slide detachment rate, bone formation and osteoblast parameters were analyzed. RESULTS: We prepared 6 plastic blocks, each containing 5 tibias, whose cross sections were on the same plane. The blocks were completely polymerized and suitable for sectioning. Flowing CO into the embedding solution reduced the polymerization time and increased the rate of complete polymerization. Application of the embedding solution on the section surface significantly reduced the detachment rate of the sections ( < 0.05) without affecting bone formation analysis ( > 0.05). Heating the slides significantly lowered the detachment rate of the sections ( < 0.05) without affecting osteoblast analysis ( > 0.05). CONCLUSIONS The optimized method allows effective embedding of multiple undecalcified mice tibias in the same block and can be an ideal method for histological analysis of undecalcified bones.
Animals ; Mice ; Plastics ; Staining and Labeling ; Tibia ; Tissue Embedding ; methods

OBJECTIVE: To assess the value of Ploton silver staining and phalloidin-iFlour 488 staining in observation of the morphology of osteocyte dendrites of mice at different developmental stages. METHODS: The humerus and femurs were harvested from mice at 0 (P0), 5 (P5), 15 (P15), 21 (P21), 28 (P28), and 35 days (P35) after birth to prepare cryo-sections and paraffin sections. HE staining of P35 mouse femur sections served as a reference for observing osteocytes in the trabecular bone and cortical bone. The humeral sections at different developmental stages were stained with Ploton silver staining to observe the morphology of osteocytes and canaliculi, and the canalicular lengths in the cortical and trabecular bones of the humerus of the mice in each developmental stage were recorded. The cryo-sections of the humerus from P10 and P15 mice were stained with phalloidin iFlour-488 to observe the morphology of osteocytes and measurement of the length of osteocyte dendrites in the cortical bone. RESULTS: In the trabecular bone of the humerus of P0-P15 mice, Ploton silver staining only visualized the outline of the osteocytes, and the morphology of the canaliculi was poorly defined. In P21 or older mice, Ploton silver staining revealed the morphology of the trabecular bone osteocytes and the canaliculi, which were neatly arranged and whose lengths increased significantly with age (P21 CONCLUSIONS Mouse osteocyte dendrites elongate progressively and their arrangement gradually becomes regular with age. Ploton silver staining can clearly visualize the morphology of the osteocytes and the canaliculi in adult mice but not in mice in early stages of development. Phalloidin iFlour-488 staining for labeling the cytoskeleton can be applied for mouse osteocytes at all developmental stages and allows morphological observation of mouse osteocytes in early developmental stages.
Animals ; Bone and Bones ; Dendrites ; Mice ; Osteocytes ; Phalloidine ; Silver Staining