The Duration of Hardware Retention After Radiologic Union of Surgically Treated Femoral Neck Fractures in Children May Predict the Aggravation or Occurrence of Avascular Necrosis of the Femoral Head or Neck After Hardware Removal.

BACKGROUND: The incidence of aggravation or occurrence of avascular necrosis (AVN) following hardware removal in surgically treated pediatric femoral neck fractures who achieved radiologic consolidation is unknown. This study aimed to investigate the risk factors for this complication. METHODS: Seventy-one pediatric (mean age: 9.8±3.9 y) were retrospectively analyzed. Risk factors (age, sex, laterality, severity of initial displacement, type of fracture, time from trauma to reduction, reduction and fixation method, quality of reduction, time required to achieve radiologic union, duration of hardware retention, presence of AVN before hardware removal and follow-up time) were recorded. The severity of AVN was assessed based on radiographs with Ratliff's classification. RESULTS: Following hardware removal, the aggravation/occurrence of AVN was detected in 11 hips (15.5%). Among the 5 hips (7%) with aggravation of AVN, 1 (1.4%) with type II AVN and 3 (4.2%) with type III AVN exhibited aggravation of type I AVN, while the remaining hip (1.4%; type I) showed enlargement of the involved AVN area. Six hips (8.5%) developed AVN following hardware removal: 2 (2.8%) were classified as type I and 4 (5.6%) as type III. Receiver operating characteristic curve analysis indicated that hardware retention >7 months after union is associated with a decreased rate of aggravation or occurrence of AVN of the femoral neck or head following hardware removal. CONCLUSIONS: The incidence of aggravation or occurrence of AVN following hardware removal in surgically treated pediatric femoral neck fractures is 15.5%; hardware retention >7 months after radiologic union may reduce the risk of aggravation or occurrence of AVN of the femoral neck or head postimplant removal. LEVEL OF EVIDENCE: Level III.

CircUTRN24/miR-483-3p/IGF-1 Regulates Autophagy Mediated Liver Fibrosis in Biliary Atresia.

Biliary atresia (BA) is a rare neonatal cholestatic disease that presents with a marked bile duct reaction and rapid fibrotic development. Our earlier research has shown that circUTRN24 is highly elevated in BA, but the exact molecular mechanism is still unknown. This study attempted to investigate whether circUTRN24 induces BA liver fibrosis through regulation of autophagy and to elucidate its molecular mechanism. Using TGF-ß-treated hepatic stellate cells (HSC) LX-2, we created a liver fibrosis model. qRT-PCR was used to analyze the expression of circUTRN24, miR-483-3p, and IGF-1. Western blot analysis was used to assess the expression of IGF-1, HSC activation-related proteins, and autophagy-related proteins. The TGF-ß-induced LX-2 cell fibrosis model was then supplemented with circUTRN24 siRNA, miR-483-3p mimics, and the autophagy activator Rapamycin, and functional rescue tests were carried out to investigate the role of circUTRN24, miR-483-3p, and autophagy in BA liver fibrosis. Using a luciferase reporter assay, a direct interaction between miR-483-3p and circUTRN24 or IGF-1 was discovered. With the increase of TGF-ß treatment concentration, circUTRN24 expression also gradually increased, as did HSC activation and autophagy-related protein. si-circUTRN24 significantly decreased circUTRN24 expression and inhibited HSC activation and autophagy, which was reversed by Rapamycin. Through bioinformatics prediction and validation, we found circUTRN24 might act through miR-483-3p targeting IGF-1 in the autophagy-related mTOR pathway. Furthermore, miR-483-3p mimics significantly increased miR-483-3p expression and inhibited HSC activation and autophagy, which were reversed by Rapamycin. Functional rescue experiments showed that si-circUTRN24 inhibited circUTRN24 and IGF-1 expressions and promoted miR-483-3p expression, while the miR-483-3p inhibitor abolished these effects. These findings imply that circUTRN24/miR-483-3p/IGF-1 axis mediated LX-2 cell fibrosis by regulating autophagy.

Lilly's Technique for Delayed Hemorrhage After Choledochal Cyst Radical Surgery.

Background: Choledochal cysts (CCs) are characterized by dilations of the extra- and/or intrahepatic bile ducts. Surgery (cyst excision and Roux-en-Y hepaticojejunostomy) remains the gold standard for treatment. However, delayed hemorrhage can occur postoperatively, and although rare, it can be life-threatening. This study aimed to determine the risk factors and corresponding prevention of delayed hemorrhage after radical CC surgery, and to apply a technique to lower its incidence. Materials and Methods: This retrospective study enrolled 267 patients who received CC surgery between June 2016 and December 2020 at Shenzhen Children's Hospital. Univariate and multivariate logistic regression analyses were performed to identify risk factors for delayed hemorrhage. Results: Eleven (4.1%) patients had delayed hemorrhage after laparoscopic radical surgery. The most common hemorrhage site was the dissected surface between the cyst and adjacent structures with chronic severe adhesions, postoperatively. The occurrence of recurrent CC-associated complication and excessive total blood loss during surgery were risk factors for delayed hemorrhage after CC radical surgery. Length of disease course, operation when cholangitis/pancreatitis still existed, cyst diameter, and application of trypsin inhibitor after the surgery were not significantly different between the two groups. Conclusion: For patients without adhesions, complete cyst resection is the gold standard. However, for those with intensive adhesions, in cases of delayed hemorrhage on the dissection surface and malignancy transformation risk, the Lilly's technique with Roux-en-Y hepaticojejunostomy could be an alternative.

Interaction between human leukocyte antigen (HLA-C) and killer cell Ig-like receptors (KIR2DL) inhibits the cytotoxicity of natural killer cells in patients with hepatoblastoma.

Background: Hepatoblastoma (HB) is the most common liver malignancy in childhood with poor prognosis and lack of effective therapeutic targets. Single-cell transcriptome sequencing technology has been widely used in the study of malignant tumors, which can understand the tumor microenvironment and tumor heterogeneity. Materials and methods: Two children with HB and a healthy child were selected as the research subjects. Peripheral blood and tumor tissue were collected for single-cell transcriptome sequencing, and the sequencing data were compared and analyzed to describe the differences in the immune microenvironment between children with HB and normal children. Results: There were significant differences in the number and gene expression levels of natural killer cells (NK cells) between children with HB and normal children. More natural killer cells were seen in children with HB compared to normal control. KIR2DL were highly expressed in children with HB. Conclusion: Single-cell transcriptome sequencing of peripheral blood mononuclear cells (PBMC) and tumor tissue from children with HB revealed that KIR2DL was significantly up-regulated in NK cells from children with HB. HLA-C molecules on the surface of tumor cells interact with inhibitory receptor KIR2DL on the surface of NK cells, inhibiting the cytotoxicity of NK cells, resulting in immune escape of tumors. Inhibitors of related immune checkpoints to block the interaction between HLA-C and KIR2DL and enhance the cytotoxicity of NK cells, which may be a new strategy for HB treatment.

An aptasensor strip-based colorimetric determination method for kanamycin using cellulose acetate nanofibers decorated DNA-gold nanoparticle bioconjugates.

The preparation of portable colorimetric biosensor strips is described by combining aptamer-immobilized electrospun nanofiber membranes (A-NFMs) with signal probes (DNA-conjugated gold nanoparticles (AuNPs)) for determination of kanamycin (KMC) as a model analyte. The A-NFMs were decorated with complementary single-stranded DNA (cDNA) of KMC aptamer-conjugated AuNPs (cDNA@Au) to get the colorimetric biosensor strips. The constructed biosensor strips showed a significant absorbance decreasing band at 510 nm which induce a visual color change from pink to white when exposed to KMC, with a low detection limit of 2.5 nM (at S/N = 3). The effect is due to disassembling of cDNA@Au from NFMs in the presence of KMC because the aptamer has a higher affinity to KMC than its complementary DNA, which resulted in replacing cDNA@Au with KMC. Satisfactory performance was observed in real sample (drinking water and milk) analysis with a recovery of 98.9-102.2%. The constructed colorimetric biosensor test strips hold great application promise for food safety control. Graphical abstract Schematic representation of biosensor strips for kanamycin detection prepared with the cDNA@Au immobilized aptamer-based cellulose acetate nanofibers.

The assessment of sniff nasal inspiratory pressure in patients with Duchenne muscular dystrophy in China.

OBJECTIVE: Progressive weakness of respiratory muscles remains one of the leading causes of death among patients with Duchenne muscular dystrophy (DMD). Currently, there are few pulmonary function data among Chinese DMD patients. This study was carried out to evaluate the sniff nasal inspiratory pressure (SNIP) change among a group of Chinese DMD patients, and compare it with the SNIP value of patients with neuromuscular disorders in other countries. METHODS: SNIP data were collected in three research groups that consists of 581 subjects: 125 DMD boys who have taken steroid (Age 5.0-13.3, DMD-steroid group), 145 DMD steroid-naive boys (Age 5.0-13.9, DMD-nonsteroid group), and 311 healthy controls (Age 5.0-14.0, Control group). RESULTS: The SNIP for DMD-nonsteroid group, DMD-steroid group and Control group were: 56.5 (±14.3) cm H2O,66.4 (±15.5) cm H2O and 78.9 (±21.5) respectively. The SNIP in the DMD-nonsteroid group became significantly different from that of the healthy controls since age 7.0-8.9. The significant difference of SNIP between DMD-steroid group and DMD-nonsteroid group at age 7.0-10.9. The peak value of SNIP in the DMD-nonsteroid group appeared at age 8.7, and decreased dramatically thereafter, while in DMD-steroid group and the Control group peaked at 10.2 years and 12.2 years respectively. There was a bit difference between SNIP in this group and that in previous researches which may be due to geographical distribution and ethnic backgrounds. CONCLUSION: This study strengthens the previous findings that SNIP can be used to evaluate respiratory dysfunction during the early stage of young patients with neuromuscular disorders, and demonstrates that steroid is effective in slowing the decrease of SNIP in this group of Chinese DMD boys.