Objective:To explore the calvarial critical size defect (CSD)in rats with type 2 diabetes mellitus(T2DM).Methods:T2DM model of SD rats(weighted 300-320 g)was induced by high fat and high sugar diet and low dose intraperitoneal streptozotocin (STZ)injection.The rats with T2DMand the normal controls were divided into 4 groups(n=3)respectively.Defects with the diame-ter(mm)of 2,3,4 and 5 were made on the central calvaria of each rat.General observation,X-ray examination and histological study were performed 8 weeks postoperatively.Results:In the T2DM group,only the defects of 2 mm diameter were healed completely,X-ray resistance and new bone formation were observed;the defects of 3,4 and 5 mm diameter were unhealed,X-ray transmission was observed and newly formed bone was insufficient.In the control group,the defects of 2,3 and 4 mm diameter were healed completely, X-ray resistance and new bone formation were observed;the defects of 5 mm diameter were unhealed,X-ray transmission was ob-served,newly formed bone was insufficient.Conclusion:The calvarial CSD of T2DM rat model can be defined as the defect with the diameter of 3 mm.

Diabetes mellitus is a complex metabolic disease involving multiple organ systems in the body.In recent years,its global incidence rate has increased year by year.In China,the blood glucose control of patients with diabetes mellitus who receive oral hypogly-cemic agents or insulin treatment remains poor.In the early disease stages,exercise is important to control blood glucose levels.Recently,many studies have found that the occurrence of type 2 diabetes mellitus was related to declining levels of irisin,an exercise-related muscle factor.Furthermore,studies have found that irisin improved insulin resistance,promoted the production of pancreatic isletβcells,and affected the body's glucose and lipid metabolism.In addition,its levels were also implicated in the occurrence of various complications,such as diabetic nephropathy and diabetes-related cardiovascular diseases.This article summarizes and analyzes the role of irisin in the occurrence and development of diabetes mellitus and further describes its impact and mechanism on various diabetic complications.

OBJECTIVETo compare the difference of the diameters of superior mesenteric vein (SMV) and gastrocolic trunk (GCT) between patients with cecum-ascending colon cancer and normal individuals, and to assess the diagnostic value of the diameters of SMV and GCT in cecum-ascending colon cancer.

METHODSPreoperative imaging data of 60 patients with primary cecum-ascending colon cancer confirmed by postoperative pathology at the First Affiliated Hospital of Sun Yat-sen University from June 2014 to December 2016 were retrospectively analyzed. The diameters of SMV and GCT were measured on preoperative CT images. SMV was measured at about 2 cm below the junction of SMV and splenic vein. GCT was measured at 1 cm near the proximal junction of right colon vein, right gastroepiploic vein and anterior pancreaticoduodenal vein. Another 60 people receiving pelvic CT examination without organ illness were collected as control. The diameter differences of SMV and GCT between cancer group and control group were compared. The diagnostic value of the diameters of SMV and GCT in cecum-ascending colon cancer was evaluated by receiver operating characteristic (ROC) curves.

RESULTSAmong 60 cases of cecum-ascending colon cancer, 36 were males and 24 were females with median age of 48 years (range 28-84); 13 were cecum cancer, 47 were ascending colon cancer; 11 had no lymph node and liver metastasis, 40 had lymph node metastasis, 9 had liver metastasis (all with lymph node metastasis). Compared to control group, the diameters of SMV and GCT in cancer group were significantly longer [SMV:(11.2±1.3) mm vs. (9.5±1.7) mm, t=6.04, P<0.001; GCT:(5.5±0.9) mm vs. (3.5±1.0) mm, t=11.51, P<0.001]. However, there were no statistically significant differences in diameters of SMV and GCT among hepatic metastasis, lymph node metastasis and no metastasis cancer groups (all P>0.05). The ROC curve analysis showed that the area under the curve of SMV diameter was 0.777, and the optimal cut-off point was 10.5 mm in the diagnosis of cecum-ascending colon cancer, with the sensitivity and specificity of 95.0%(57/60) and 46.7%(28/60) respectively. The area under the curve of GCT diameter was 0.923, and the optimal cut-off point was 4.5 mm in the diagnosis of cecum-ascending colon cancer, with sensitivity and specificity of 88.3%(53/60) and 85.0%(51/60) respectively.

CONCLUSIONThe dilation of the SMV and GCT may be used as warning factors for cecum-ascending colon cancer, especially the diameter of GCT.

Adult ; Aged ; Aged, 80 and over ; Cecum ; Colon, Ascending ; pathology ; Colonic Neoplasms ; pathology ; Female ; Humans ; Male ; Mesenteric Veins ; anatomy & histology ; Middle Aged ; Retrospective Studies

Alveolar bone is an important anatomic basis for implant-supported denture restoration, and its different degrees of defects determine the choices of bone augmentation surgeries. Therefore, the reconstruction of alveolar bone defects is an important technology in the clinical practice of implant restoration. However, the final reconstructive effect of bone quality, bone quantity and bone morphology is affected by many factors. Clinicians need to master the standardized diagnosis and treatment principles and methods to improve the treatment effect and achieve the goal of both aesthetic and functional reconstruction of both jaws. Based on the current clinical experience of domestic experts and the relevant academic guidelines of foreign counterparts, this expert consensus systematically and comprehensively summarized the augmentation strategies of alveolar bone defects from two aspects: the classification of alveolar bone defects and the appropriate selection of bone augmentation surgeries. The following consensus are reached: alveolar bone defects can be divided into five types (Ⅰ-0, Ⅰ-Ⅰ, Ⅱ-0, Ⅱ-Ⅰ and Ⅱ-Ⅱ) according to the relationship between alveolar bone defects and the expected position of dental implants. A typeⅠ-0 bone defect is a bone defect on one side of the alveolar bone that does not exceed 50% of the expected implant length, and there is no obvious defect on the other side; guided bone regeneration with simultaneous implant implantation is preferred. Type Ⅰ-Ⅰ bone defects refer to bone defects on both sides of alveolar bone those do not exceed 50% of the expected implant length; the first choice is autologous bone block onlay grafting for bone increments with staged implant placement or transcrestal sinus floor elevation with simultaneous implant implantation. Type Ⅱ-0 bone defects show that the bone defect on one side of alveolar bone exceeds 50% of the expected implant length, and there’s no obvious defect on the other side; autologous bone block onlay grafting (thickness ≤ 4 mm) or alveolar ridge splitting (thickness > 4 mm) is preferred for bone augmentation with staged implant placement. Type Ⅱ-Ⅰ bone defects indicate that the bone plate defect on one side exceeds 50% of the expected implant length and the bone defect on the other side does not exceed 50% of the expected implant length; autologous bone block onlay grafting or tenting techniques is preferred for bone increments with staged implant implantation. Type Ⅱ-Ⅱ bone defects are bone plates on both sides of alveolar bone those exceed 50% of the expected implant length; guided bone regeneration with rigid mesh or maxillary sinus floor elevation or cortical autologous bone tenting is preferred for bone increments with staged implant implantation. This consensus will provide clinical physicians with appropriate augmentation strategies for alveolar bone defects.