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The understanding of cellular energy metabolism activation by engineered scaffolds remains limited, posing challenges for therapeutic applications in tissue regeneration. This study presents biosynthesized poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] and its major degradation product, 3-hydroxybutyrate (3HB), as endogenous bioenergetic fuels that augment cellular anabolism, thereby facilitating the progression of human bone marrow-derived mesenchymal stem cells (hBMSCs) towards osteoblastogenesis. Our research demonstrated that 3HB markedly boosts in vitro ATP production, elevating mitochondrial membrane potential and capillary-like tube formation. Additionally, it raises citrate levels in the tricarboxylic acid (TCA) cycle, facilitating the synthesis of citrate-containing apatite during hBMSCs osteogenesis. Furthermore, 3HB administration significantly increased bone mass in rats with osteoporosis induced by ovariectomy. The findings also showed that P(3HB-co-4HB) scaffold substantially enhances long-term vascularized bone regeneration in rat cranial defect models. These findings reveal a previously unknown role of 3HB in promoting osteogenesis of hBMSCs and highlight the metabolic activation of P(3HB-co-4HB) scaffold for bone regeneration.

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OBJECTIVE: Distal clavicle fracture classification directly affects the treatment decisions. It is unclear whether the classification systems implemented differ depending on surgeons' backgrounds. This study aimed to compare the interobserver agreement of four classification systems used for lateral clavicle fractures by shoulder specialists and general trauma surgeons. METHODS: Radiographs of 20 lateral clavicle fractures representing a full spectrum of adult fracture patterns were analyzed by eight experienced shoulder specialists and eight general trauma surgeons from 10 different hospitals. All cases were graded according to the Orthopedic Trauma Association (OTA), Neer, Jäger/Breitner, and Gongji classification systems. To measure observer agreement, Fleiss' kappa coefficient (κ) was applied and assessed. RESULTS: When only X-ray films were presented, both groups achieved fair agreement. However, when the 3D-CT scan images were provided, improved interobserver agreement was found in the specialist group when the OTA, Jäger/Breitner, and Gongji classification systems were used. In the generalist groups, improved agreement was found when using the Gongji classification system. In terms of interobserver reliability, the OTA, Neer, and Jäger/Breitner classification systems showed better agreement among shoulder specialists, while a slightly lower level of agreement was found using the Gongji classification system. For the OTA classification system, interobserver agreement had a mean kappa value of 0.418, ranging from 0.446 (specialist group) to 0.402 (generalist group). For the Neer classification system, interobserver agreement had a mean kappa value of 0.368, ranging from 0.402 (specialist group) to 0.390 (generalist group). For the Jäger/Breitner classification system, the inter-observer agreement had a mean kappa value of 0.380, ranging from 0.413 (specialist group) to 0.404 (generalist group). For the Gongji classification system, interobserver agreement had a mean kappa value of 0.455, ranging from 0.480 (specialist group) to 0.485 (generalist group). CONCLUSION: Generally speaking, 3D-CT scans provide a richer experience that can lead to better results in most classification systems of lateral clavicle fractures, highlighting the value of digitization and specialization in diagnosis and treatment. Competitive interobserver agreement was exhibited in the generalist group using the Gongji classification system, suggesting that the Gongji classification is suitable for general trauma surgeons who are not highly experienced in the shoulder field.

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Base composition skews (G-C/G+C) of mitochondrial genomes are believed to be primarily driven by mutational pressure, which is positively correlated with metabolic rate. In marine animals, metabolic rate is also positively correlated with locomotory capacity. Given the central role of mitochondria in energy metabolism, we hypothesised that selection for locomotory capacity should be positively correlated with the strength of purifying selection (dN/dS), and thus be negatively correlated with the skew magnitude. Therefore, these two models assume diametrically opposite associations between the metabolic rate and skew magnitude: positive correlation in the prevailing paradigm, and negative in our working hypothesis. We examined correlations between the skew magnitude, metabolic rate, locomotory capacity, and several other variables previously associated with mitochondrial evolution on 287 crustacean mitogenomes. Weakly locomotory taxa had higher skew magnitude and ω (dN/dS) values, but not the gene order rearrangement rate. Skew and ω magnitudes were correlated. Multilevel regression analyses indicated that three competing variables, body size, gene order rearrangement rate, and effective population size, had negligible impacts on the skew magnitude. In most crustacean lineages selection for locomotory capacity appears to be the primary factor determining the skew magnitude. Contrary to the prevailing paradigm, this implies that adaptive selection outweighs nonadaptive selection (mutation pressure) in crustaceans. However, we found indications that effective population size (nonadaptive factor) may outweigh the impact of locomotory capacity in sessile crustaceans (Thecostraca). In conclusion, skew magnitude is a product of the interplay between adaptive and nonadaptive factors, the balance of which varies among lineages.

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Polyhydroxyalkanoates (PHAs) are a class of structurally diverse natural biopolyesters, synthesized by various microbes under unbalanced culture conditions. PHAs as biomedical materials have been fabricated in various forms to apply to tissue engineering for the past years due to their excellent biodegradability, inherent biocompatibility, modifiable mechanical properties, and thermo-processability. However, there remain some bottlenecks in terms of PHA production on a large scale, the purification process, mechanical properties, and biodegradability of PHA, which need to be further resolved. Therefore, scientists are making great efforts via synthetic biology and metabolic engineering tools to improve the properties and the product yields of PHA at a lower cost for the development of various PHA-based scaffold fabrication technologies to widen biomedical applications, especially in bone tissue engineering. This review aims to outline the biosynthesis, structures, properties, and the bone tissue engineering applications of PHA scaffolds with different manufacturing technologies. The latest advances will provide an insight into future outlooks in PHA-based scaffolds for bone tissue engineering.

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BACKGROUND: Angiogenesis plays an important role in the development of rheumatoid arthritis (RA), which increases the supply of nutrients, cytokines, and inflammatory cells to the synovial membrane. Genistein (GEN), a soy-derived isoflavone, has been validated that can effectively inhibit the angiogenesis of several tumours. We thus carried out a study in vitro to investigate the effect of GEN in vascular endothelial growth factor (VEGF) expression and angiogenesis induced by the inflammatory environment of RA. METHODS: MH7A cells were used to verify whether GEN can inhibit the expression of VEGF in MH7A cells under inflammatory conditions and demonstrate the mechanism. EA.hy926 â€‹cells were used to verify whether GEN can inhibit the migration and tube formation of vascular endothelial cells in inflammatory environment. RESULTS: GEN dose-dependently inhibited the expression and secretion of interleukin (IL)-6 and VEGF, as well as the nucleus translocation of Signal transducer and activator of transcription 3 (STAT3) in MH7A. Furthermore, GEN inhibited IL-6-induced vascular endothelial cell migration and tube formation in vitro. CONCLUSION: GEN inhibits IL-6-induced VEGF expression and angiogenesis partially through the Janus kinase 2 (JAK2)/STAT3 pathway in RA, which has provided a novel insight into the antiangiogenic activity of GEN in RA. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: Our study provides scientific guidance for the clinical translational research of GEN in the RA treatment.

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Al foil for high-voltage aluminum electrolytic capacitor was first D.C. etched in HCl-H2SO4 mixed acidic solution to form main tunnels and then D.C. etched in natural NaCl solution containing 0.1% H2C2O4 and different trace amounts of Zn(NO3)2. Between the two etching processes, Zn nuclei were deposited on the interior surface of the main tunnels by the natural occluded corrosion cell effect to form micro Zn-Al galvanic local cells. The effects of Zn nuclei on the cross-section etching and electrochemical behavior of Al foil were investigated using scanning electron microscopy, polarization curve measurement, and electrochemical impedance spectroscopy. The sub-branch tunnels can form along the main tunnels owing to the formation of Zn-Al micro-batteries, in which Zn is the cathode and Al is the anode. Increasing Zn(NO3)2 concentration increases the number of Zn nuclei that can serve as sites for branch tunnel initiation along the main tunnels, thereby enhancing the specific capacitance of etched Al foil.

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OBJECTIVE: This study was performed to compare the clinical efficacy of three internal fixation methods for distal clavicle fractures (Neer type II): clavicular hook plate (Group A), anatomical plate (Group B), and arthroscopic Endobutton (Group C). METHODS: From 2001 to 2014, 58 patients with Neer type II distal clavicle fractures were treated at our institution. The clinical results were assessed with the visual analog scale (VAS), Constant score, and Simple Shoulder Test (SST) score. RESULTS: All patients had anatomic reduction and bone healing at the final follow-up. Groups B and C had considerably less intraoperative blood loss than Group A. The incision was significantly shorter in Group C than in Groups A and B. The mean VAS score was significantly higher in the affected than unaffected shoulder. The Constant and SST scores were significantly higher in the unaffected than affected shoulder. The VAS, Constant, and SST scores of the affected shoulders were not significantly different among the three groups. CONCLUSIONS: Arthroscopic Endobutton fixation has long-term clinical results similar to those of other surgical protocols for distal clavicle fractures (Neer type II). We recommend this technique because of less blood loss, shorter incision length, and less shoulder irritation than other methods.

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Up to date, the scarcity of publicly available complete mitochondrial sequences for European wild pigs hampers deeper understanding about the genetic changes following domestication. Here, we have assembled 26 de novo mtDNA sequences of European wild boars from next generation sequencing (NGS) data and downloaded 174 complete mtDNA sequences to assess the genetic relationship, nucleotide diversity, and selection. The Bayesian consensus tree reveals the clear divergence between the European and Asian clade and a very small portion (10 out of 200 samples) of maternal introgression. The overall nucleotides diversities of the mtDNA sequences have been reduced following domestication. Interestingly, the selection efficiencies in both European and Asian domestic pigs are reduced, probably caused by changes in both selection constraints and maternal population size following domestication. This study suggests that de novo assembled mitogenomes can be a great boon to uncover the genetic turnover following domestication. Further investigation is warranted to include more samples from the ever-increasing amounts of NGS data to help us to better understand the process of domestication.

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Heterotopic ossification (HO) is a pathological phenomenon in which ectopic lamellar bone forms in soft tissues. HO involves many predisposing factors, including congenital and postnatal factors. Postnatal HO is usually induced by fracture, burn, neurological damage (brain injury and spinal cord injury) and joint replacement. Recent studies have found that patients who suffered from bone fracture combined with severe traumatic brain injury (S-TBI) are at a significantly increased risk for HO occurrence. Thus, considerable research focused on the influence of S-TBI on fracture healing and bone formation, as well as on the changes in various osteogenic factors with S-TBI occurrence. Brain damage promotes bone formation, but the exact mechanisms underlying bone formation and HO after S-TBI remain to be clarified. Hence, this article summarises the findings of previous studies on the relationship between S-TBI and HO and discusses the probable causes and mechanisms of HO caused by S-TBI. The translational potential of this article: A better understanding of the probable causes of traumatic brain injury-induced HO can provide new perspectives and ideas in preventing HO and may support to design more targeted therapies to reduce HO or enhance the bone formation.

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Polyamidoamine (PAMAM) dendrimers as synthetic gene vectors are efficient gene delivery systems. In this study, a kind of α-cyclodextrin-PAMAM conjugates polymer (Cy D-G1) was synthesized as a gene delivery vector. Based on ~1H NMR detectation, about 6.4 PAMAM-G1 molecules was grafted onto an α-CD core. Agarose gel electrophoresis revealed that Cy D-G1 could efficiently bind with DNA to condense them into nano-scale particles, which showed a similar binding capacity of PEI-25 K. Besides, it could protect DNA from DNase I degradation in a low N/P ratio. When N/P ratio in the CyD-G1/DNA polyplex was 40, the average particle size of CyD-G1/DNA polyplex was about 120 nm, and zeta potential was +21 mV. This polyplex could maintain its particle size in serum-containing solution within 360 min. In comparison with PEI-25 K carrier, CyD-G1 showed low cytotoxicity in various cell lines. Cell transfection results showed that CyD-G1 efficiently delivered DNA into cells at N/P = 80 compared with Lipofectamine 2000 and PEI-25 K. Unlike Lipofectamine 2000 and PEI-25 K, in serum-containing test condition, CyD-G1/DNA polyplex could maintain the transgene activities. The results of confocal laser scanning microscopy indicated that most DNA entered into cell nuclei within 4 h, and this phenomenon was consistent with the results calculated by flow cytometry. Taken together, CyD-G1 showed good transgene activities and the gene delivery vector could be used not only in vitro but also in vivo.

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To investigate the effect that folic acid-modified polyrotaxanes(FPP) transfered siRNA CD47 to inhibit melanoma proliferation, the expression of CD47 in clinical melanoma patients was tested by Western blot and RT-PCR, respectively. Physical performance of FPP(siRNA-CD47: CD47) nanoparticles was tested by Malvern particle size instrument and scanning electron microscope. The clone formation experiment demonstrated that FPP(CD47) nanoparticles inhibited the growth of clones. Invasion assay revealed that FPP(CD47) inhibited migration of B16F10 cells. Tumor bearing mice were used in the experiment to test the efficacy of FPP(CD47) treatment. Compared with the control group, high expression of CD47 was observed in the clinical melanoma patients. FPP(CD47) nanoparticle size at 80 nm exhibited a potential of 10 m V; compared with FPP(Con), fluorescence intensity was significantly reduced to 4.2% and B16F10 cell clone formation was decreased by 91% in the FPP(CD47) treatment. Tumor volume of tumor-burdened mice was decreased by 90% with FPP(CD47) treatment. FPP(CD47) lowered CD47 protein and m RNA expression in the tumor. This study suggests that FPP may transfer siRNA CD47 into the cancer cells to inhibit melanoma growth effectively.

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OBJECTIVE: To analyze effects of fracture of processus styloideus ulnae on prognosis in the treatment of distal radial fracture of type C according to AO classification. METHODS: This was a retrospective case-control study, and the information was got ten through case evaluation and follow-up, including sex, age, patient satisfaction, Gartland & Werley score and radiographic score. There were 76 patient treated with open reduction and plate fixation in People's Hospital Affiliated to Peking University from July 2006 to July 2011. All the patients were divided into two groups: no combination with fracture of processus styloideus ulnae (group A, 56 cases), combination with fracture of processus styloideus ulnae (group B, 20 cases). The patients in group A and B were treated with open reduction and internal fixation; however the fracture of processus styloideus ulnae was not fixed. The indexes such as clinical data, bone grafting, joint movement, Gartland & Werley score and radiographic score were compared between two groups. RESULTS: The ulnaris pain of patients in group B was more obvious than that in group A. The local VAS, palmar and dorsal flexion degree of wrist joint, motion VAS, patients satisfaction score, radial and ulnar deviation degree, pronation and supination of forearm degree, Gartland & Werley score and radiographic score were separately 0.1 ± 0.1, (51.1 ± 1.9)°, (60.2 ± 1.9)°, 0.6 ± 0.1 (23.1 ± 0.9)°, (28.7 ± 1.3)° (81.5 ± 2.6)°, (68.2 ± 2.7)° 1.9 ± 0.3, 89.6 ± 12.3 in group A; and separately 0.3 ± 0.3, (51.4 ± 2.3)°, (66.6 ± 1.7)°, 0.5 ± 0.2, (24.5 ± 2.0)°, (26.9 ± 1.8)°, (80.3 ± 2.5)°, (70.3 ± 3.7)°, 1.2 ± 0.4, 92.5 ± 7.5 in group B; there were no statistical differences in above indexes between two groups. CONCLUSION: Whether the distal radial fracture with a concomitant unrepaired ulnar styloid fracture or not exerts no influence on mainly outcomes including function, radiography and motion of the wrist.

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OBJECTIVE: To study clinical-related characteristics of sociology of postoperative distal radius fracture patients. METHODS: A multi-center retrospective research was conducted on the information of the case evaluation and follow-up, including the patients' gender, age, habits, history of chronic diseases, conditions of fracture, length of hospital stay and treatments. The epidemiology data were analyzed with SPSS15.0. RESULTS: Of the entire 143 patients, 52 were male (average age: 41), and 91 were female (average age: 61). The different gender and age groups had significant distinction in the characteristics of injury. The length of hospital stay was influenced by the energy of injury. CONCLUSION: To reduce the damage or incidence of distal radius fracture, we should avoid falling, strengthen protection awareness, treat internal medicine diseases or osteoporosis and so on. The knowledge of characteristics of sociology and injury of distal radius fracture is beneficial to the prevention and treatment.

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OBJECTIVE: To observe the clinical effect of biodegradable conduit small gap tublization to repair peripheral nerve injury. METHODS: In the study, 30 cases of fresh peripheral nerve injury in the upper extremities were recruited. After formally informed and obtaining the consent, the recruited patients were divided into the degradable chitin conduit tublization group (experimental group: 15 cases) and traditional epineurial neurorrhaphy group (control group: 15 cases). Their nerve functional recovery conditions were clinically observed according to the standard score methods provided by SHEN Ning-jiang and British Medical Research Council. The excellent and good rates of the overall nerve functional recovery were calculated. The electrophysiologic study was carried out after 6 months. RESULTS: Of the total 30 cases, 28 were followed up, and there were 14 cases in the degradable chitin conduit tublization group and traditional epineurial neurorrhaphy group. The operation procedure was very simple, and the mean suture time [(8.0±0.8) min] was 20% shorter than that of the traditional epineurial neurorrhaphy group [(10.0±0.6) min]. All the wounds in the degradable chitin conduit tublization group healed as expected without rejection, hypersensitive reaction or anomalous draining. Electrophysiology examination results after 6 months displayed that the sensory nerves conduction velocity recovery rate was 77.37% of the normal value, and motor nerve conduction velocity recovery rate was 70.09% in the degradable chitin conduit tublization group. The sensory nerves conduction velocity recovery rate was 61.69% of the normal value, and motor nerve conduction velocity recovery rate was 56.15% in the traditional epineurial neurorrhaphy group. The exact propability methods was applied in the comparison of sensory and motor nerve conduction velocity recovery rate, and there was no statistically significant of two groups(sensory nerve conduction velocity recovery rate P=0.678;motor nerve conduction velocity recovery rate P=0.695). The combinated functional recovery excellent and good rates after repair in the degradable chitin conduit tublization group were 78.57%, while 28.57% in the traditional epineurial neurorrhaphy group. The Fisher's exact probabilistic method was applied in the comparison of combinated functional recovery excellent and good rates, and there was statistically significant of two groups(P=0.021). CONCLUSION: The operation procedure of the degradable chitin conduit tublization is very simple and the clinical recovery effect is much better than that of the traditional epineurial neurorrhaphy. The biodegradable conduit small gap tublization methods to repair peripheral nerve injury has the possibility to substitute the traditional epineurial neurorrhaphy.

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OBJECTIVE: To investigate the treatment effect of open arthrolysis for elbow stiffness. METHODS: From Aug. 2007 to Apr. 2012, 17 cases of elbow stiffness were treated with open arthrolysis,in which, 11 were post-traumatic stiffness and 6 elbow stiffness resulted from rheumatoid arthritis and osteoarthritis. The preoperative Mayo elbow score was 65.1±16.4. Posterior middle approach was applied for 15 cases, and primary lateral approach for 2 cases. The ulnar nerve release and antedisplacement were performed for 12 cases with series limited flexion. The mobile hinged fixator were applied for 2 cases of unstable elbow after debridement of series hero ossification. RESULTS: With follow-up time for 6 to 41 months (average 13.1 months), all the patients acquired the follow-up and evaluation. According to Mayo elbow score of the last follow-up, the score was 87.5±16.7, and compared with the preoperation, the difference was significant: 9 cases were excellent, 6 good, 1 fair, and 1 poor, and the total excellent and good rate was 88.23%. The active range of motion (ROM) of flexion-extension was 110.6°±27.5°. However, 1 case developed chronic infection, and 1 ulnar nerve symptom. CONCLUSION: In applying open arthrolysis to treat elbow stiffness, as long as we release completely and assure stable elbow and early postoperative motion, we can get satisfying results.

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OBJECTIVE: To investigate the surgical treatment results of periprosthetic femur fracture after hip arthroplasty. METHODS: In the study, 10 patients from Oct. 2006 to Jan. 2012 were treated surgically according to Vancouver classification, and their fracture union, hip function, pain in fracture site and lower extremity length were evaluated postoperatively. RESULTS: All the patients had full follow-up for 6 to 69 months (mean time: 35.1 months). All fractures were united well with good alignment and no prosthesis loosing or internal fixation failure was discovered. Harris scores to assess hip function were 71 to 90 (mean: 79.8) and the excellent and good rate was 70%. VAS scores to evaluate pain in fracture site when walking were 0 to 3 (mean: 1.4). The lengths of injured lower extremity were shorter by 0 to 2.5 cm than those of the contralateral side preoperatively [mean (1.6±0.9) cm]. The shortened lengths were reduced to 0 to 1.8 cm postoperatively [mean (0.6±0.6) cm], which were statistically different from those of preoperation (P=0.002). CONCLUSION: Although treatment of periprosthetic femur fracture after hip arthroplasty is a hard work, we can make individual therapy regiment based on the patient's age, general condition, function demand and Vancouver classification. Surgical treatment can bring good results.

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In this study, a novel amphiphilic block copolymer biomaterial - poly (ethylene glycol)-poly (caprolactone) (PEG-PCL), was used to entrap norcantharidin (NCTD), taking advantage of self-assembly theory. Dialysis and volatilization dialysis were used to prepare copolymer micelles. Drug-loaded micelles were compared with blank micelles in terms of their particle diameter, morphology and IR spectral characteristics. The results revealed that there was no significant difference in respect of morphology and IR spectrum, but particle size differed. Drug-loaded micelles had a smaller particle size than blank micelles. Three important factors influencing particle size, the drug loading content (LC) and the drug entrapment efficiency (EE) of the NCTD-loaded micelles, were studied. The results indicated that the method of preparation and the type of organic solvent had a significant influence on the size of the micelles. LC and EE were greatly affected by the ratio of NCTD to copolymer. In vitro release of NCTD from the conjugate micelles showed that its release rate depended on the pH of the phosphate buffer solution (PBS). The amount released was higher at lower pH than under neutral conditions. In vitro antitumor activity of the NCTD conjugate against human hepatoma (HepG2) cell line and human lung cancer (A549) cell line was evaluated by the MTT method. Micelles loaded with NCTD demonstrated greater and more satisfactory cell viability inhibition than the free drug. In vivo antitumor activity of drug-loaded micelles was investigated in mice bearing S180 mouse sarcoma. NCTD-loaded micelles displayed tumor inhibition effects, better than the free drug. As a new drug delivery system, copolymer micelles present many advantages including easy formulation, good water solubility, low toxicity and high treatment efficacy, and show great potential as carriers of hydrophobic drugs.

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OBJECTIVE: To evaluate the ASES, Constant and HSS score systems and their significance on postoperative function of the shoulder. METHODS: Totally 172 cases of proximal humeral fracture of five affiliated hospital from September 2004 to September 2008 were analyzed. All the functional outcome of the involved shoulder were evaluated by ASES, Constant, HSS score and patient self score. The correlations and agreement of three shoulder scales were analyzed with Pearson correlation test and Bland-Altman plot in different age groups and fracture types. RESULTS: (1) The Constant score were lower than other two scores in the same age group and fracture type (F = 13.62 and 4.80, P < 0.05). (2) The correlations between three shoulder scales: ASES and Constant (r = 0.754, P = 0.0003), ASES and HSS (r = 0.755, P = 0.0001), Constant and HSS (r = 0.858, P = 0.0002). The correlations between three shoulder scales and patient self evaluation: ASES (r = 0.602, P = 0.0002), Constant (r = 0.705, P = 0.0001), HSS (r = 0.663, P = 0.0037). The Bland-Altman plot shows three shoulder scales have good agreement. (3)The correlation between Constant score and patient self evaluation decreased in the elder group and severe fracture type. CONCLUSIONS: ASES, Constant, HSS shoulder score systems are all fit to evaluate the functional outcome of the shoulder, they have good correlation and agreement. Constant score in recommended for its high correlation coefficient with patient self evaluation score. However, its age bias must be paid attention in clinical practice. ASES shoulder score can be used in remote follow-up.

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BACKGROUND: Erinaceidae is a family of small mammals that include the spiny hedgehogs (Erinaceinae) and the silky-furred moonrats and gymnures (Galericinae). These animals are widely distributed across Eurasia and Africa, from the tundra to the tropics and the deserts to damp forests. The importance of these animals lies in the fact that they are the oldest known living placental mammals, which are well represented in the fossil record, a rarity fact given their size and vulnerability to destruction during fossilization. Although the Family has been well studied, their phylogenetic relationships remain controversial. To test previous phylogenetic hypotheses, we combined molecular and morphological data sets, including representatives of all the genera. METHODOLOGY AND PRINCIPAL FINDINGS: We included in the analyses 3,218 bp mitochondrial genes, one hundred and thirty-five morphological characters, twenty-two extant erinaceid taxa, and five outgroup taxa. Phylogenetic relationships were reconstructed using both partitioned and combined data sets. As in previous analyses, our results strongly support the monophyly of both subfamilies (Galericinae and Erinaceinae), the Hylomys group (to include Neotetracus and Neohylomys), and a sister-relationship of Atelerix and Erinaceus. As well, we verified that the extremely long branch lengths within the Galericinae are consistent with their fossil records. Not surprisingly, we found significant incongruence between the phylogenetic signals of the genes and the morphological characters, specifically in the case of Hylomys parvus, Mesechinus, and relationships between Hemiechinus and Paraechinus. CONCLUSIONS: Although we discovered new clues to understanding the evolutionary relationships within the Erinaceidae, our results nonetheless, strongly suggest that more robust analyses employing more complete taxon sampling (to include fossils) and multiple unlinked genes would greatly enhance our understanding of the Erinaceidae. Until then, we have left the nomenclature of the taxa unchanged; hence it does not yet precisely reflect their phylogenetic relationships or the depth of their genetic diversity.

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BACKGROUND: There are few researches for the healing of metaphyseal fractures; moreover, the animal models to study the metaphyseal fractures are usually made by the oscillating saw osteotomy without reliable fixation, which is not in accordance with our current clinical practice. In this study, we established a new model to observe the healing process of metaphyseal fractures. METHODS: Eighteen New Zealand rabbits were used in the study. The fracture model was created by splitting the medial tibial plateau in rabbits, then reset, and fixed with compression screws. At 1, 2, 3, 4, 6, and 8 weeks postoperatively, the tibial specimens were collected; firstly, a general observation and an X-ray examination of the specimens was done, and then they were embedded in methylmethacrylate and cut into sections with hard tissue slicer. The sections were stained with Giemsa reagent and examined under light microscopy. RESULTS: There was no fracture displacement in the tibial specimens of all time points, except for one showing a collapse. No external callus formation could be observed by X-ray and general examination. After 1 week of the operation, the fracture gap was filled by mesenchymal tissue; 2 weeks postoperatively, a large number of woven bones were formed; from the third week onwards, the woven bone began to turn into lamellar bone, and new trabecular structure began to form. In all of the slices, no obvious chondrocytes formed in fracture areas; thus, there was no endochondral ossification. CONCLUSIONS: This model was an ideal fracture animal model and suitable for the study of metaphyseal fracture healing. The X-ray and histological images demonstrated that metaphyseal fracture healing was a process of direct bone healing through intramembranous bone formation under the conditions of minor trauma, good reduction, and firm fixation.

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