Extraction, characterization, antioxidation and anti-inflammatory activity of polysaccharides from Bupleurum chinense based on different molecular weights.

Bupleurum chinense polysaccharide has a wide range of biological activities. In this study, Bupleurum chinense polysaccharides (BPs), BPs-1 (30 kDa) and BPs-2 (2000 kDa) with different molecular weights were isolated and prepared by ultrafiltration interception method. The structures of BPs, BPs-1 and BPs-2 were characterised by monosaccharide composition, GC-MS, Fourier transform infra-red spectroscopy and nuclear magnetic resonance. The results showed that the monosaccharide composition of BPs with different molecular weights was the same, but the proportion was different. BPs, BPs-1 and BPs-2 were mainly connected by Glup-(1→,→2,4)-Araf-(1→,→6)-Glup-(1→). The anti-inflammatory activity screening experiment in vitro showed that BPs-1 had stronger anti-inflammatory effect. Antioxidant experiments showed that BPs-2 had high free radical scavenging activity. This study laid a foundation for elucidating the fine structure and structure-activity relationship of Bupleurum chinense polysaccharides and will promote the product development of Bupleurum chinense polysaccharides.

External fixator versus elastic stable intramedullary nail for treatment of metaphyseal-diaphyseal junction fractures of the pediatric distal femur: a case-control study.

BACKGROUND: Several methods have been used for the treatment of pediatric distal femoral fractures, such as elastic stable intramedullary nail (ESIN), external fixator (EF) and plate osteosynthesis, but there has been no consensus about the optimal method. The purpose of this study was to compare the clinical outcome between EF and ESIN techniques used in metaphyseal-diaphyseal junction (MDJ) fractures of the pediatric distal femur. METHODS: We retrospectively analyzed operatively treated MDJ fractures of pediatric distal femur between January 2015 and January 2022. Patient charts were reviewed for demographics, injury and data of radiography. All of the patients were divided into EF and ESIN groups according to the operation techniques. Malalignment was defined as more than 5 degrees of angular deformity in either plane. Clinical outcomes were measured by Flynn scoring system. RESULTS: Thirty-eight patients were included in this study, among which, 23 were treated with EF, and 15 with ESIN. The mean follow-up time was 18 months (12-24 months). At the final follow-up, all of the fractures were healed. Although there were no statistical differences between the two groups in demographic data, length of stay, estimated blood loss (EBL), rate of open reduction, time to fracture healing and Flynn score, the EF was superior to ESIN in operative time, fluoroscopic exposure and time to partial weight-bearing. The EF group had a significantly higher rate of skin irritation, while the ESIN had a significantly higher rate of malalignment. CONCLUSION: EF and ESIN are both effective methods in the treatment of MDJ fractures of the pediatric distal femur. ESIN is associated with lower rates of skin irritation. However, EF technique has the advantages of shorter operative time, reduced fluoroscopic exposure, and shorter time to partial weight-bearing, as well as lower incidence of malalignment. LEVEL OF EVIDENCE: Level III.

Conservative versus surgical treatment of Gartland type II supracondylar humeral fractures in children.

The purpose of the study was to compare the efficacy of conservative and surgical treatments for Gartland type II supracondylar humerus fractures in children. We assessed 142 patients with type II supracondylar humerus fractures treated in our hospital from February 2018 to February 2019. The patients were divided into two groups: initial conservative treatment (Group A) and initial surgical treatment (Group B). Clinical outcomes were measured by the Flynn scoring system. Variables were analyzed using a statistical approach between those groups. All patients were followed up for 6-12 months. The rate of loss reduction was 19.8% in patients treated conservatively, and the incidence of pin infections was 7.1% in patients treated surgically. Although there were no statistical differences between the three groups in fracture healing time and Flynn score, the conservative treatment was superior to surgical treatment in functional recovery times. At the last follow-up, all fractures had healed without iatrogenic vascular or nerve injury, Volkmann's contracture, or cubit varus deformity. Conservative treatment is safe and effective for the treatment of Gartland type II supracondylar fracture and represents a faster recovery time of elbow range of motion as compared with surgical treatment. Type IIB had a 41.3% risk of secondary displacement versus 5.3% for IIA, but we still prefer closed reduction. However, closed reduction of Garland type II must be followed accurately in the first 2 weeks to identify patients with loss of reduction. The patients who loss reduction can be treated with percutaneous pinning, and the clinical effect was consistent with immediate surgical treatment. Level of evidence: level III.

Compression screw internal fixation versus non-weight-bearing cast immobilization for Jones fractures in children.

BACKGROUND: Several methods have been used to treat pediatric Jones fractures, but there has been no consensus about the optimum method. The purposes of this study were to compare the clinical outcomes between compression screw and non-weight-bearing techniques used in pediatric Jones fractures and clarify the most suitable treatment option for this population. METHODS: Twenty-one patients who presented with Jones fractures between January 2015 and June 2021 were analyzed retrospectively. They were divided into the compression screw group (n=10) and cast immobilization (n=11) group. The following parameters were compared between them: demographic data; times to radiographic union, full weight bearing, and return to daily life; and the American Orthopaedic Foot and Ankle Society (AOFAS) foot scores at 3 months postoperatively and the final follow-up. RESULTS: The two groups did not differ significantly with respect to age, sex, laterality, and preoperative displacement. The mean immobilization time and times to radiographic union, full weight bearing, and return to daily life were significantly shorter in the compression screw group than in the cast immobilization group. The AOFAS scores at the final follow-up did not differ significantly between the two groups. One case of refracture and delayed union each were observed in the non-weight-bearing cast group. However, no patients experienced nonunion. CONCLUSIONS: Compression screw and non-weight-bearing cast techniques are effective methods for treating pediatric Jones fractures. The complication rate was lower in pediatrics than in adults. However, compared with the non-weight-bearing cast technique, the compression screw technique has the advantages of a shorter radiographic union time, shorter immobilization times, and earlier return to full weight bearing and daily life. We recommend compression screw fixation for widely displaced fractures and school-age and active adolescents to avoid delays in healing, nonunion, disruption to daily living, and time off school. LEVEL OF EVIDENCE: Level III.

Treatment of unstable pelvic fractures in children with an external fixator: Retrospective study of 56 patients.

Purpose: We retrospectively analyzed the data of patients who underwent external fixation treatment for unstable pelvic fractures and evaluated the clinical effects of this treatment and factors influencing pelvic function recovery. Methods: The data of patients with unstable pelvic fractures treated with an external fixator between January 2006 and December 2018 were retrospectively analyzed. The analyzed parameters included demographic data, fracture healing, pelvic asymmetry, deformity index, and complications. Fractures were categorized using the Tiles classification. Pelvic function was evaluated using the Cole score. Pelvic risk factors were identified using univariate and multivariate logistic regression analyses. Results: Fifty-six patients (29 and 27 with type B and C fractures, respectively) were included. All fractures were healed at the time of the final follow-up. Nine and three patients had pin tract infections and loosened external fixators postoperatively, respectively. Pelvic asymmetry was reduced from 1.34 ± 0.15 cm to 0.70 ± 0.19 cm (p < 0.01), and the deformity index decreased from 0.13 ± 0.03 to 0.07 ± 0.02 (p < 0.01). The Cole score was excellent and good in 41 and 15 patients, respectively. Risk factors for pelvic function recovery included injury severity score > 25.5, age > 11.3 years, and lower-extremity fractures. Conclusions: External fixation is an effective method for treating unstable pelvic fractures in children, with the advantages of a simple operation, short surgical time, no interference with treatments for associated injuries, and avoidance of re-trauma caused by open reduction. An ISS > 25.5, patient age > 11.3 years, and associated lower-extremity fractures are predictors of pelvic function recovery. Level of evidence: Level IV.

Elastic stable intramedullary nailing versus Kirschner wire in the treatment of pediatric metaphyseal-diaphyseal junction fractures of the distal radius: a case-control study.

BACKGROUND: Several methods have been used for the treatment of pediatric distal radius fractures, such as the elastic stable intramedullary nail (ESIN), Kirschner wire (K-wire), and plate, but there has been no consensus about the optimum method. The purpose of this study was to compare ESIN and K-wire techniques used in metaphyseal-diaphyseal junction (MDJ) fractures of the pediatric distal radius. METHODS: The data of patients who were treated at a children's hospital affiliated with Shandong University between August 2018 and January 2022 were analyzed retrospectively. The children were divided into the ESIN and K-wire groups. Clinical outcomes were measured by the Gartland and Werley scoring system. Variables were analyzed using a statistical approach between the two groups. RESULTS: The study included 26 patients, of whom 11 were treated with K-wire and 15 with ESIN. At the final follow-up, all of the fractures were healed. There were no differences in terms of age, sex, fracture location, or wrist function score. However, the ESIN was superior to K-wire in operative time, fluoroscopic exposure, and estimated blood loss (EBL). CONCLUSIONS: K-wire and ESIN are both effective methods in the treatment of MDJ fractures of the pediatric distal radius. The use of the ESIN technique represents less EBL, fluoroscopy exposure, and operation time compared with K-wire. We recommend osteosynthesis by ESIN rather than K-wires in patients with MDJ fractures of the distal radius. LEVEL OF EVIDENCE: III, a case-control study.

External fixator as a safe method in the treatment of distal tibial fractures in children.

OBJECTIVE: The objective of this study is to evaluate the functional and radiological results of external fixator application in the treatment of distal tibial metaphyseal diaphyseal junction (MDJ) fractures in children and to analyze differences between stable and unstable fractures. METHODS: Medical records of children with distal tibial MDJ fracture confirmed by imaging from January 2015 to November 2021 were retrospectively analyzed. Patients were divided into stable and unstable groups and parameters, including clinical and imaging data and Tornetta ankle score were compared. RESULTS: Twenty-five children, comprising 13 with stable and 12 with unstable fractures, were included in our study. The mean age was 7 years (range, 2-13.1 years), and there were 17 males and 8 females. All children had closed reduction, and the basic clinical data of the two groups were comparable. Stable fractures showed shorter intraoperative fluoroscopy, operation, and fracture healing times than unstable fractures. No significant difference in Tornetta ankle score was observed. Twenty-two patients had excellent ankle score, and three had a good ankle score, for a combined incidence of 100%. Two patients in the stable fracture group and one in the unstable fracture group developed a pin site infection, and one patient with unstable fracture showed a length discrepancy (discrepancy<1 cm). CONCLUSION: External fixator is safe and effective for the treatment of distal tibial MDJ fractures, whether the fracture is stable or not. It has the advantages of minimally invasive, excellent ankle function score, few major complications, needless auxiliary cast fixation, and early functional exercise and weight bearing. LEVEL OF EVIDENCE: Level IV.

Comparison of diagnosis and treatment of MSSA and MRSA osteomyelitis in children: a case-control study of 64 patients.

BACKGROUND: We aimed to compare the clinical characteristics of acute osteomyelitis caused by methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA) in children. METHODS: We retrospectively analyzed the data of 64 children treated between September 2017 and June 2021. Based on the bacterial culture results, they were divided into MRSA and MSSA infection groups. Both groups were treated with debridement and vacuum-assisted closure for negative pressure drainage. Parameters including clinical manifestations, number of operations, length of hospital stay, inflammatory indicators, and concurrent arthritis were compared between the two groups. RESULTS: In the MRSA infection group, there was one case each of residual joint stiffness and pathological fracture. Conversely, the MSSA group had two cases of residual joint stiffness. The MRSA infection group was more prone to high fever (t = 3.61, P = 0.001), white blood cell count elevation (t = 2.41, P = 0.022), arthritis (X2 = 7.48, P = 0.013), metastatic abscess (X2 = 4.78, P = 0.042), and a shorter length of progression from onset to admission (t = - 2.04, P = 0.046); however, it required more surgeries (t = 2.68, P = 0.009) and longer hospital stay (t = 2.04, P = 0.045). CONCLUSIONS: Pediatric acute osteomyelitis caused by MRSA is more prone to cause high fever and markedly elevated of white blood cell count, and is often accompanied with suppurative infection of adjacent joints and metastatic abscesses, thus requiring more surgeries and longer hospital stay.

Molecular Dynamics Simulation Analysis of Damage and Expansion Process of Nanoindentation Single-Crystal 3C-SiC Carbide Specimens at Different Temperature.

The molecular dynamics method was used to analyze the influence of simulated temperature on the damage expansion process of the 3C-SiC sample under nano-indentation loading in order to study the influence of temperature on the internal damage and expansion mechanism of the 3C-SiC single crystal sample further during the nano-indentation loading process. A simulation test platform for diamond indenter indentation was established. The process of stress and strain distribution, dislocation evolution, dislocation expansion and potential energy change were analyzed, combined with the radial distribution function and load displacement curve. The influence of temperature on the 3C-SiC material was discussed. The variation trend of the potential energy-step curve is basically the same at the temperatures of 0 K, 300 K, 600 K and 900 K. The difference in strain distribution was characterized by the influence of temperature on stress intensity, expansion direction and type. The microcosmic manifestation is the significant difference in the dislocation slip at low temperature. In the process of dislocation evolution and expansion, dislocation climbs at room temperature and increases at high temperature, which is closely related to energy release. This study has certain guiding significance for investigating the internal damage difference and temperature effect of the 3C-SiC sample.

Screening of Codonopsis radix Polysaccharides with Different Molecular Weights and Evaluation of Their Immunomodulatory Activity In Vitro and In Vivo.

Polysaccharide is one of the main components of Codonopsis radix (CR) and has good immune activity. However, the immune activity of CR polysaccharides with different molecular weights has not been systematically screened. In this study, the polysaccharides of CR from Pingshun of Shanxi Province (PSDSs) were first divided into two groups using ultrafiltration: 3.3 kDa (PSDSs-1) and more than 2000 kDa (PSDSs-2). The immunomodulatory effects of PSDSs with different molecular weights were evaluated in vitro and in vivo. In vitro experimental results showed that compared with Lipopolysaccharide-induced macrophages, PSDSs-1 increased TNF-α and IL-6 levels and decreased IL-10. Meanwhile, PSDSs-2 showed the opposite effect, indicating the difference in pro- and anti-inflammatory activities of PSDSs with different molecular weights. The immunosuppressive model of cyclophosphamide proved that PSDSs have immune-promoting function, with PSDSs-1 exhibiting a better effect than PSDSs-2. In vitro and in vivo experiments illustrated the complexity of PSDS immunomodulation. Further research on the functions of PSDs with different molecular weights is needed to lay a foundation for their classification and application.

Molecular evolution of influenza A (H3N2) viruses circulated in Fujian Province, China during the 1996-2004 period.

We studied the genetic and epidemic characteristics of influenza A (H3N2) viruses circulated in human in Fujian Province, south of China from 1996 to 2004. Phylogenetic analysis was carried out for genes encoding hemagglutinin1 (HA1) of influenza A virus (14 new and 11 previously reported reference sequences). Our studies revealed that in the 8 flu seasons, the mutations of HA1 genes occurred from time to time, which were responsible for about four times of antigenic drift of influenza H3N2 viruses in Fujian, China. The data demonstrated that amino acid changes were limited to some key codons at or near antibody binding sites A through E on the HA1 molecule. The changes at the antibody binding site B or A or sialic acid receptor binding site 226 were critical for antigenic drift. But the antigenic sites might change and the key codons for antigenic drift might change as influenza viruses evolve. It seems important to monitor new H3 isolates for mutations in the positively selected codons of HA1 gene in south of Asia.