BACKGROUND:Displacement of the distal fracture fragment is one of the most important facts that lead to cubitus varus fol owing pediatric supracondylar humeral fracture. Mainstream technique emphasized the restoration of posterior-ulnar deviation of the distal fragment. However, there is an absence of supportive evidences from biomechanical studies. OBJECTIVE:To establish models of extension-ulnar type of supracondylar humeral fracture and investigate the mechanical stability of reduced fracture with residual displacements within functional restoration standard, so as to provide mechanic evidences supporting the empirical rule of manipulative reduction-“better anterior than posterior, better radial than ulnar”. METHODS:The fresh cadaveric bone of right upper extremity from a 7-year-old child was scanned using CT. Models of supracondylar humeral fracture differing in contact area of the fracture site and displacement direction of the distal fragment were established and underwent loading tests. Stress in both anterior and posterior margin of the fracture site and Baumann angle were recorded, and data were analyzed and compared. RESULTS AND CONCLUSION:In comparison of stress in the posterior margin, the value was significantly greater in the posteromedial-displacement group than the others. Stress value in fracture with 75%contact area was significantly greater than the other three groups. In comparison of stress in the anterior margin, a significantly greater value was obtained in the posteromedial-displaced group. Stress value in fracture with 85%contact area was significantly greater. When comparing stress in posterior margin and anterior margin, the absolute increment of stress value was greater in posterior displacement group than in anterior displacement group. Baumann angle increased significantly when fragment displaced medial y. Above findings indicated that displacement direction altered the location of stress concentration. Stress augmentation was greater in posterior displacement group. Stress in related area significantly increased constantly when contact area of the fracture site reduced. Baumann changed obviously when fragment displaced medial y. The results preliminarily verify the hypothesis that displacement of the distal fragment was the main contributor to cubitus varus fol owing supracondylar humeral fracture. These findings provided certain evidences supporting the empirical rule“better anterior than posterior, better radial and ulnar”.

Objective To summary the pathological and genetic features in nine Chinese limb girdle muscular dystrophy 2I (LGMD2I) patients.Methods Nine LGMD2I patients were recruited from Peking University First Hospital between 2011 and 2016, who came from nine unrelated and non-consanguineous families.The mean age of onset was (8.2±5.2) years (2 to 19 years), and the mean disease duration was (10.4±6.1) years (1 to 24 years).There were six males and three females, present with weakness in limb girdle muscles, four of whom accompanied with calf hypertrophy and three with scapular winging.Serum creatine kinase was 964-23 131 U/L (normal 25-190 U/L).Five of them who conducted electromyogram showed myogenic pattern.Muscle biopsy and next generation sequencing were performed in these patients, then sanger sequencing was performed to determine whether the variants co-segregated with the phenotype in these families.Results Muscle biopsy revealed myopathy features in six patients, dystrophic change in one, and only mild changes in two.Major histocompatibility complex-Ⅰ was positive in six cases, and rimmed vacuoles were found in two.There were seven mutations in fukutin-related protein (FKRP) gene.A reported mutation of c.545A>G (p.Y182C) appeared in eight cases, including three homozygotes and five compound heterozygotes.The mutation of c.1067T>C (p.Ile356Thr) was reported too.And c.1263C>A (p.Tyr421X), c.534G>T(p.Thr178Cys), c.1027G>C (p.Glu343Gln), c.1027G>T(p.Glu343X), c.1448A>G (p.Tyr483Cys) were found to be novel mutations.Conclusions LGMD2I showed large variation in myopathology.The missense mutation A545G(Y182C) is a hot spot of FKRP gene in our series.

Objective:To investigate the relationship between central venous-arterial blood carbon dioxide partial pressure difference (Pcv-aCO 2) and left ventricular ejection fraction(LVEF) in acute myocardial infarction. Methods:Clinical data of patients with acute myocardial infarction admitted to the Intensive Care Unit of Fujian Provincial Hospital from November 2019 to October 2021 were retrospectively analyzed. LVEF was measured by bedside echocardiogram. The patients were divided into the normal LVEF group (LVEF ≥ 52%) and decreased LVEF group (LVEF < 52%) according to LVEF. The differences in general information and hemodynamic parameters between the two groups were compared. The normality of the above data was tested by the Jarque-Bera test. Correlation analysis of hemodynamic indices with LVEF was performed. Binary logistic regression was used to analyze the risk factors associated with the decrease in LVEF. The feasibility of diagnosing LVEF decline with Pcv-aCO 2 was assessed using receiver operating characteristic (ROC) curve. Results:Seventy-two patients with acute myocardial infarction were included for analysis, including 25 patients in the normal LVEF group and 47 patients in the decreased LVEF group. Pcv-aCO 2 was significantly higher in the decreased LVEF group than that in the normal LVEF group [(7.13±1.19) mmHg vs. (5.41±1.23) mmHg, P<0.01]. There was a negative correlation between LVEF and Pcv-aCO 2 ( rs= -0.740, P<0.01). The area under the ROC curve for Pcv-aCO 2 was 0.849 (95% CI: 0.758-0.939, P<0.01). The binary logistic regression analysis showed that Pcv-aCO 2 was an independent risk factor for decreased LVEF ( OR=2.251, 95% CI: 1.326-3.820). Conclusions:To a certain extent, the increase of Pcv-aCO 2 can predict the decrease of LVEF in acute myocardial infarction.

Objective:To investigate the effect of extraction of mandibular third molar (M3) tooth germ on the development of the mandible in orthodontic patients, with a view to providing a reference for clinical M3 tooth germ extraction.Methods:One hundred and twenty-nine Angel class Ⅰ malocclusion patients aged 10-16 years who attended the Department of Orthodontics Division 1, School & Hospital of Stomatology, Wuhan University from 1 January 2013 to 30 December 2021 and fulfilled the criteria for nativity were included. Those who had their M3 extracted in the Department of Oral and Maxillofacial Surgery were included in the study group, with a total of 66 cases; and those who did not have their M3 extracted were included in the control group, with a total of 63 cases. The average annual growth was calculated by tracing point measurements on cephalometric films before and after orthodontic treatment according to the Jarabak and McNamara methods, with measurements of the mandibular ramus height (Ar-Go′), mandibular body length (Go′-Me), and overall mandibular length (Co-Gn) values, respectively. The average annual growth of Ar-Go′, Go′-Me, and Co-Gn were compared between the two groups for the overall sample of patients, patients of the same sex (male/female), patients of the same age group (>10 and ≤12 years old, >12 and ≤14 years old, >14 and ≤16 years old), and patients of the same cervical vertebral maturation stage (stages Ⅱ, Ⅲ, and Ⅳ), respectively, to see if there was any difference in the average annual growth of Ar-Go′, Go′-Me, and Co-Gn.Results:There was no statistically significant difference in the average annual growth of Ar-Go′, Go′-Me, and Co-Gn between the study group [0.88 (0.40, 1.80), 0.67 (0.15, 1.18), and 0.86 (0.40, 1.90) mm, respectively] and the control group [1.08 (0.45, 1.60), 0.53 (0.25, 1.13), and 1.20 (0.46, 2.28) mm, respectively] ( P>0.05). In addition, there was no significant difference in the average annual growth in the Ar-Go′, Go′-Me, and Co-Gn between the groups for patients of the same sex group, patients of the same age group, and patients of the same cervical vertebral maturation stage group( P>0.05). Conclusions:Extraction of the mandibular third molar tooth germ has no significant effect on the development of the mandible in Angle class Ⅰ malocclusion patients.

Objective To produce rabbit polyclonal antibody against mouse testis expressed 38 (TEX38). Methods Full-length open reading frame sequence of TEX38 was amplified and inserted into the pET-30a-(+) vector to construct pET-30a-TEX38 prokaryotic plasmid. The recombinant plasmid was transformed into E.coli BL21, and expression was induced with isopropyl β-D-thiogalactopyranoside (IPTG). New Zealand white rabbits were immunized with TEX38 protein after purification and denaturation, then TEX38 polyclonal antibodies were collected from rabbit serum samples. ELISA was performed to detect the antibody titer. Western blot and immunofluorescence staining were performed to determine the specificity of TEX38 polyclonal antibodies. Results The pET-30a-TEX38 recombinant plasmid was constructed, and TEX38 prokaryotic protein was expressed and purified successfully. After immunization, the titer of TEX38 antibody reached 1:1 000 000. Western blot analysis and immunofluorescence staining showed that TEX38 was localized in the mouse spermatogenic cells and sperms with a good specificity. Conclusion The rabbit polyclonal antibody against mouse TEX38 is successfully produced, and the expression of TEX38 in mouse spermatogenic cells and sperms is validated.
Male ; Rabbits ; Animals ; Mice ; Testis ; Antibodies ; Enzyme-Linked Immunosorbent Assay ; Immunization ; Spermatozoa ; Escherichia coli