Laboratory animal ethics education improves medical students' awareness of laboratory animal ethics.

OBJECTIVE: In this study, we added laboratory animal ethics education into both didactic sessions and practical sessions the general surgery laboratory course, with the didactic sessions focus on teaching the fundamental principles of laboratory animal ethics, while the practical sessions emphasize the application of these principles in laboratory classes and have assessed the changes in medical students' perception of laboratory animal ethics following medical students exposure to such education. METHODS: One hundred and eighty-nine third-year medical students from Wuhan University's Second Clinical College completed a laboratory animal ethics awareness questionnaire and a laboratory animal ethics written examination before and after laboratory animal ethics education. RESULTS: After receiving laboratory animal ethics education, the percentage of students who supported euthanasia for the execution of animals and humane treatment of laboratory animals were 95.2% and 98.8%, respectively, which did not differ from the 94.9% and 96.4% observed before the education. Moreover, there was a notable increase in the proportion of students who knew about regulations related to laboratory animals (from 39.9% to 57.1%), welfare issues (from 31.9% to 50.0%), and the 3R principle (from 30.4% to 58.9%) post-education, all statistically significant at P < 0.05. Test scores also showed improvement, with students scoring (93.02 ± 11.65) after education compared to (67.83 ± 8.08) before, a statistically significant difference. CONCLUSIONS: This research helps to provide information for the good practices of laboratory animal ethics education. After receiving laboratory animal ethics education, students are better able to treat laboratory animals in a correct animal ethical manner. Laboratory animal ethics education helps improve students' knowledge of laboratory animal ethics. Students' perception towards how the laboratory animal ethics course should be delivered may vary. Still, new courses or better organized courses on laboratory animal ethics education are required in order to provide students an in-depth understanding.

NIR-triggered photodynamic therapy of traumatic heterotopic ossification with a type II collagen-targeted photosensitizer.

Traumatic heterotopic ossification (HO) represents an intractable sequela following trauma with no currently effective prophylaxis or treatment. Photodynamic therapy (PDT) is a non-invasive treatment for various proliferative diseases. However, the specific effects of PDT on HO development remain unclear. In this study, the therapeutic potential of a near-infrared (NIR) probe-WL-808, composed of type II collagen-binding peptide (WYRGRL) and a PDT photosensitizer (IR-808), was evaluated for the innovative HO-targeted PDT approach. In vitro studies indicated that WL-808 could induce chondrocyte apoptosis and inhibit cell viability through ROS generation under NIR excitation. In vivo, the efficacy of WL-808-mediated PDT was tested on the tenotomy HO model mice. WL-808 specifically targeted the type II collagen cartilaginous template of HO, promoting cell apoptosis and enhancing extracellular matrix (ECM) degradation under 808 nm NIR excitation, which inhibited the final ectopic bone formation. Moreover, no obvious toxicity or side effects were detected after treatment with WL-808. Taken together, WL-808-mediated PDT significantly diminished ectopic cartilage and subsequent bone formation, providing a new perspective for HO prophylaxis and treatment.

Sustained notch signaling inhibition with a gamma-secretase inhibitor prevents traumatic heterotopic ossification.

Background: Traumatic heterotopic ossification (THO) is a devastating sequela following traumatic injuries and orthopedic surgeries. To date, the exact molecular mechanism of THO formation is still unclear, which hinders the development of effective treatments. The process of THO formation is believed to recapitulate a series of spatiotemporal cellular and signaling events that occur during skeletal development. The Notch signaling pathway is a critical genetic regulator in embryological bone development and fracture healing. However, few data are available concerning whether Notch signaling regulates THO development and maturation. Methods: We firstly detected the expressions of Notch target genes in both mouse and human THO samples with quantitative RT-PCR and immunohistochemistry (IHC). Then, tissue-resident mesenchymal progenitor cells (TMPCs) were isolated, and the abilities of the proliferation and osteogenic and chondrogenic differentiation of TMPCs were examined under the intervention of the gamma-secretase inhibitor-DAPT at different time points. Finally, DAPT was also administrated in THO mice by burn and Achilles tenotomy injury, and ectopic cartilage and bone formation were monitored by histology and micro-CT. Results: Several Notch target genes were upregulated in both mouse and human THO tissues. Sustained Notch signaling inhibition by DAPT reduced proliferation, osteogenic and chondrogenic differentiation of TMPCs in a time-dependent manner. Moreover, DAPT administration within 3 weeks could inhibit ectopic cartilage and bone formation in a mouse THO model without affecting the total body bone mass. Conclusions: The Notch signaling serves as an important therapeutic target during THO formation. And sustained gamma-secretase inhibition by DAPT has great potential in repressing chondrogenic and osteogenic differentiation of TMPCs, as well as inhibited ectopic cartilage and bone formation in vivo. The translational potential of this article: Sustained Notch inhibition via systemic DAPT (or other similar gamma-secretase inhibitors) administration has promising clinical utility for inhibiting THO formation, providing new insight into THO prophylaxis and treatment.

Early diagnosis of heterotopic ossification with a NIR fluorescent probe by targeting type II collagen.

Heterotopic ossification (HO) is a devastating sequela in which the pathologic extracellular matrix of the cartilage and bone forms abnormally in soft tissues following traumatic injuries or orthopaedic surgeries. Early treatment is essential for inhibiting the progression of HO but is currently limited by the absence of sensitive and specific early diagnosis. Herein, this study exploits the enrichment of type II collagen (Col2a1) in the HO cartilage formation stage towards developing a near-infrared (NIR) probe for early HO diagnosis, namely WL-808 by conjugating a Col2a1-binding peptide (WYRGRL) and a cyanine dye (IR-808). WL-808 exhibits high specificity for targeting the cartilage in vitro and in vivo with no apparent cytotoxicity. The NIR signal of WL-808 can be detected in the HO cartilage lesions as early as 1 week after injury when micro-CT cannot show any ectopic bone formation. Moreover, the probe is rarely distributed in the normal knee articular cartilage in vivo via the intravenous administration method. Taken together, WL-808 demonstrates great potential in early HO diagnosis under NIR imaging, facilitating early HO prophylaxis and treatment in the clinic.

Chidamide augment sorafenib-derived anti-tumor activities in human osteosarcoma cells lines and xenograft mouse model.

Previous studies have showed promising but short-lived activity of sorafenib in osteosarcoma treatments. Researches have suggested ameliorated sensitivity to standard dose of conventional cancer therapies in combination with histone deacetylase inhibitors (HDACis) through various mechanisms. Herein, for the first time, we exploited the synergism of combination therapies with sorafenib and chidamide, a member of HDACis, in the control of OS using human OS cell lines and OS xenograft mouse model and discussed interactive mechanisms between the two drugs. The combination therapy exerted a strong synergism in the inhibition of OS cell proliferation, meanwhile prominently induced cell apoptosis and cell cycle arrest in G0/G1 phase in OS cells with increased expression of MCL-1, decreased expression of caspase-3 and P21, along with diminished level of the overlapped protein P-ERK1/2. Furthermore, oral administration of the combined treatment led to a more optical therapeutic outcome, including lower degrees of tumoral cell proliferation, greater extent of apoptosis, along with induction of cell cycle arrest in tumor tissues, while exhibiting minimal toxicity. This study shows that the combination of sorafenib and chidamide can combat OS in a synergistic fashion and prompts the promising development of innovative combined therapeutic strategies for OS.

Differential expression profiles and functional prediction of circRNA in mice with traumatic heterotopic ossification.

Background: Traumatic heterotopic ossification (HO) is an intractable sequela incited by inflammatory insult. To date, the exact molecular mechanisms of traumatic HO formation remain unclear. Recent studies have indicated that circular RNAs (circRNAs) participate in various human skeletal diseases. Although the formation of HO recapitulates many programs during bone development and remodeling, few data are available concerning whether circRNAs could participate in this pathological osteogenesis. Methods: To investigate the differentially expressed circRNAs (DE-circRNAs) in HO formation, microarray assay was performed to analyze the circRNA expression profile in four pairs of mice HO tissues and normal tissues. Then, qRT-PCR was applied to verify the microarray data. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed the biological functions of the differentially expressed circRNAs target genes. Cytoscape software was used to construct the circRNA-miRNA-mRNA network for circRNAs with different expression levels as well as the target genes. Results: We demonstrated that 491 circRNAs were significantly differentially expressed in mouse HO tissues by a fold-change ≥ 2 and p-value ≤ 0.05. Among them, the expressions of 168 circRNAs were increased, while 323 were decreased. The expression levels of 10 selected circRNAs were verified successfully by qRT-PCR. GO analysis exhibited that these DE-circRNAs participated in a series of cellular processes. KEGG pathway analysis revealed that multiple upregulated and downregulated pathways were closely related to the DE-circRNAs in HO mice. The circRNA-miRNA-mRNA networks demonstrated that DE-circRNAs may be involved in the pathological osteogenesis of HO through the circRNA-targeted miRNA-mRNA axis. Conclusion: Our study first demonstrated the expression profiles and predicted the potential functions of DE-circRNAs in mice traumatic HO, which may shed new light on the elucidation of mechanisms as well as provide novel potential peripheral biological diagnostic markers and therapeutic targets for traumatic HO.

Roles of Oxidative Stress and Raftlin in Wound Healing Under Negative-Pressure Wound Therapy.

BACKGROUND: Negative-pressure wound therapy (NPWT) is an effective way to promote wound healing. However, its mechanisms have not been investigated thoroughly. Growing evidence suggests that oxidative stress and Raftlin levels play important roles in wound healing. However, whether NPWT promotes wound healing through this mechanism remains unclear. PURPOSE: Our study focuses on the different levels of oxidative stress and antioxidant response between wounds treated by NPWT and routine dressing change. The objective of this study was to measure the differences in Raftlin levels between the two groups, which is a new biomarker related to wound healing. METHODS: We divided 48 male Sprague-Dawley rats with identical full-thickness skin defects into two groups. At specific times (0, 3, 5, 7, 9, 11, and 13 days after surgery), wound tissue samples were obtained for immunohistochemistry and biochemical analysis. The expression of Raftlin and levels of oxidative stress, including malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) levels were measured by biochemical analysis. Wound-healing times were also compared. RESULTS: In the NPWT group, MDA levels were significantly decreased on days 3, 5, and 7. Furthermore, the expressions of SOD and CAT were significantly reduced on days 3 and 5. Our data also revealed that Raftlin was significantly upregulated across the whole period of wound healing. Moreover, wound healing in the NPWT group was significantly more rapid (16 days on average) than in the control group (24 days on average). On day 13 post surgery, the wound-healing percentage in the NPWT group was 91%, while that in the control group was 48%. CONCLUSION: NPWT may promote wound healing by upregulating Raftlin and inhibiting oxidative stress levels.

MiR-144-5p, an exosomal miRNA from bone marrow-derived macrophage in type 2 diabetes, impairs bone fracture healing via targeting Smad1.

BACKGROUND: Patients with diabetes have an increased risk of nonunion and delayed union of fractures. Macrophages have been shown as a key player in diabetic complications. However, it remains obscure how diabetic milieu affects macrophage-derived exosomes and its implications on osteogenic differentiation of BMSCs. In this study, we aim to define the impact of diabetic milieu on macrophage-derived exosomes, role of extracellular vesicles in intercellular communication with BMSCs, and subsequent effects on osteogenic differentiation and fracture repair. RESULTS: The osteogenic potential and the ability of fracture repair of exosomes derived from diabetic bone marrow-derived macrophages (dBMDM-exos) were revealed to be lower, as compared with non-diabetic bone marrow-derived macrophages (nBMDM-exos) in vitro and in vivo. Interestingly, miR-144-5p levels were sharply elevated in dBMDM-exos and it could be transferred into BMSCs to regulate bone regeneration by targeting Smad1. In addition, the adverse effects of dBMDM-exos on the osteogenic potential and the ability of fracture repair were reversed through the suppression of miR-144-5p inhibition in vitro and vivo. CONCLUSIONS: The results demonstrated an important role of exosomal miR-144-5p in bone regeneration, offering insight into developing new strategy for the improvement of fracture healing in patients with diabetes mellitus.

Repair of Massive Bone Defects of the Proximal Femur Using Iliac Bone Flaps of the Ascending Branch of the Lateral Circumflex Femoral Artery: A Retrospective Report.

BACKGROUND AND OBJECTIVE: The management of bone defects is still a difficult problem. Local vascularized bone grafts represent an efficient and widely used method. In this retrospective report, iliac bone flaps of the ascending branch of the lateral circumflex femoral artery were used for the management of proximal femur bone defects. PATIENTS AND METHODS: The hospital information system and clinical data collected by surgeons were retrospectively reviewed. Patients with massive bone defects of the proximal femur reconstructed with iliac bone flaps of the ascending branch of the lateral circumflex femoral artery were included. Relevant data, including general information, perioperative treatment, and imaging data during follow-up, were retrieved for analysis. Five patients (4 males and 1 female) aged 18 to 42 years were included in this report. All patients were diagnosed with proximal femoral bone defects. The sizes of the bone defects ranged from 5 ×4 cm to 8 × 5 cm. Harris hip score was adopted to evaluate the functional outcomes. The adverse events were recorded. The mean follow-up time was 6.3 years. RESULTS: Iliac bone flaps of the ascending branch of the lateral circumflex femoral artery were transferred locally for the 5 patients. Bone flaps were fixed with plates in 4 cases and Kirschner wires in 1 case. The hospital stay was 12 to 27 days, with an average of 19.4 days. All cases achieved bony healing after 3 to 6 months postoperatively. The Harris hip scores ranged from 87 to 95 at final follow-up. All patients achieved good to excellent functional outcomes. One superficial infection occurred. No other adverse events or serious adverse events were noted. CONCLUSIONS: Local transfer of iliac bone flaps of the ascending branch of the lateral circumflex femoral artery represents a safe and effective method for the reconstruction of massive bone defects of the proximal femur.

Reconstruction of a Distal Foot Skin Defect Using an Intermediate Dorsal Neurocutaneous Flap.

OBJECTIVE: To present the use of an intermediate dorsal neurocutaneous flap for the reconstruction of defects on the distal foot. METHODS: From September 2016 to October 2018, five patients (mean age at operation 33.8 years; range, 7-70 years; female/male = 2/3) with skin defects on one of their feet caused by road-traffic accidents, electrical injury, and syndactyly correction were retrospectively reviewed. The size of the defects ranged from 2.0 cm × 1.0 cm to 5.0 cm × 3.5 cm. All patients had undergone a reconstruction surgery using intermediate dorsal neurocutaneous flap. One patient underwent a syndactyly correction, and four patients first experienced aggressive debridement. The sizes of the flaps were between 5.0 cm × 2.0 cm and 6.0 cm × 4.0 cm. The function, appearance, and pain of the injured foot were assessed using the Chinese Manchester Foot Pain and Disability Index and visual analogue scale. RESULTS: These five patients were systematically followed up for a mean of 15.8 months (range, 12-20 months). The donor sites were closed primarily in two cases, and skin grafts were performed in three cases. All the flaps survived with a success rate of 100%; the wounds healed well, and the color matches were excellent. Partial superficial flap necrosis occurred in one of five flaps, which was treated by dressing change using a hypertonic saline gauze. No significant problems were found at the donor site in any patient immediately afterwards or at follow-up. There were no problems in any patients associated with wearing shoes. Based on the Chinese Manchester Foot Pain and Disability Index, four patients were strongly satisfied and one was satisfied with the recovery of physical function; all the patients were strongly satisfied with the appearance of the injured foot; all five patients had an excellent score of pain intensity subscale. Except for one patient who reported mild pain, all the other patients reported no pain based on the visual analogue scale. Two typical cases are presented in this paper. CONCLUSIONS: The intermediate dorsal neurocutaneous flap is an alternative and effective technique that can reliably cover minor- to medium-sized defects on the distal foot, toes, and web spaces. This surgical method leads to satisfactory functional recovery with minimal donor site morbidity, and no major vessels need to be sacrificed. This procedure offers an advisable option for orthopaedic surgeons to treat defects on the distal foot.

MicroRNA-126: a promising biomarker for angiogenesis of diabetic wounds treated with negative pressure wound therapy.

BACKGROUND: Negative pressure wound therapy represents an effective therapy to treat nonhealing diabetic wounds by promoting angiogenesis, of which the mechanism hasn't been investigated thoroughly. Growing evidence suggests that miRNAs hold great potential to be clinical biomarkers, and miR-126 is an essential angiogenesis regulator in diabetic wound repair. PURPOSE: Our study aims to explore the effect of NPWT on the expression of miR-126 in the wound tissue and plasma of diabetic rat models and the association between circulating miR-126 and two quantitative indexes of angiogenesis. METHODS: Full-thickness excisional wounds were created on the back of diabetic rats. Measure the wound closure and collect the wound tissue and blood for H&E, immunohistochemistry, Western blot and RT-PCR. Here we demonstrated that significantly increased capillary density and arteriolar density in the NPWT group at each specified time-point. RESULTS: In the NPWT group, miR-126 expression was significantly increased on days 3, 5, 7, and 9 (P<0.05). Furthermore, statistically significant increases in VEGF mRNA and protein expression and p-ERK expression, as well as decreased SPRED1 expression, were noted upon treatment with NPWT on day 9. Our data revealed that miR-126 expression in the wound and plasma was significantly associated (P<0.05). Moreover, a positive correlation was also detected between increased levels of circulating miR-126 and arteriolar density, as well as capillary density (P<0.05). CONCLUSION: The study suggested that miR-126 was upregulated by NPWT and could represent a promising monitoring tool for angiogenesis in diabetic wounds treated with NPWT.

Long-term follow-up of fibular graft for the reconstruction of bone defects.

The use of fibular graft for the reconstruction of bone defects has been demonstrated to be a reliable method. The aim of this study was to assess the clinical outcome of graft union, functional outcome (hypertrophy of the graft bones) and complications of both non-vascularized and vascularized grafts.From 1981 to 2015, 10 patients were treated using non-vascularized fibular graft or free vascularized fibular graft. The outcomes were bony union time, graft hypertrophy and complications based on radiograph and functional outcomes according to the Musculoskeletal Tumor Society (MSTS) score. Mobility of the ankle at the donor site was evaluated using the Kofoed ankle score system.This study included 10 patients with an average follow-up of 6.8 years. The union rate for all patients was 100%. The mean union time was 21.3 weeks for vascularized fibular grafts and 30.5 weeks for non-vascularized fibular grafts (P = .310). There was a significant difference between the upper limbs and the lower limbs regarding hypertrophy of the grafts in 5 patients (P = .003). The mean MSTS score in 10 patients was 84% (range 53%-97%). Stress fracture of the graft occurred in 1 patient. Donor site complications, including valgus deformity and length discrepancy, between 2 legs occurred in 2 patients who were under 18 years of age at the time of operation (P = .114). The mean Kofoed score was 96.8 (range 88-100).A greater increase in hypertrophy of grafts was observed with reconstruction in the lower limbs. There was no difference in MSTS score between these 2 types of grafts. Children were more likely to experience the valgus deformity at the donor site after harvesting the fibula. Keeping at least the distal 1/4 of the fibula intact during the surgery is a valid means of ensuring ankle stability at the donor site, and children should be considered for prophylactic distal tibiofibular synostosis creation to prevent the valgus deformity of the ankle at the donor site.

Negative pressure wound therapy promotes muscle-derived stem cell osteogenic differentiation through MAPK pathway.

Negative pressure wound therapy (NPWT) has been revealed to be effective in the treatment of open fractures, although the underlying mechanism is not clear. This article aimed to investigate the effects of NPWT on muscle-derived stem cell (MDSC) osteoblastic differentiation and the related potential mechanism. The cell proliferation rate was substantially increased in NPWT-treated MDSCs in comparison with a static group for 3 days. There was no observable effect on the apoptosis of MDSC treated with NPWT compared with the control group for 3 days. The expression levels of HIF-1α, BMP-2, COL-I, OST and OPN were increased on days 3, 7 and 14, but the expression level of Runx2 was increased on days 3 and 7 in the NPWT group. Pre-treatment, the specific inhibitors were added into the MDSCs treated with NPWT and the control group. ALP activity and mineralization were reduced by inhibiting the ERK1/2, p38 and JNK pathways. The expression levels of Runx2, COL-I, OST and OPN genes and proteins were also decreased using the specific MAPK pathway inhibitors on days 3, 7 and 14. There were no significant effects on the expression of BMP-2 except on day 3. However, the expressions of the HIF-1α gene and protein slightly increased when the JNK pathway was inhibited. Therefore, NPWT promotes the proliferation and osteogenic differentiation of MDSCs through the MAPK pathway.

MicroRNAs as a novel class of diagnostic biomarkers for the detection of osteosarcoma: a meta-analysis.

MicroRNAs (miRNAs) have been considered as promising diagnostic biomarkers for many diseases, especially for cancers. Numerous studies have reported the value of miRNAs in the diagnosis of osteosarcoma (OS), but the results vary greatly across different studies. Therefore, we conducted this meta-analysis to assess the prospective diagnostic value of miRNAs in diagnosing OS. All relevant articles from prior to July 28, 2017 were selected from PubMed, EMBASE, Web of Science, Cochrane Library, Chinese National Knowledge Infrastructure, and Wan-fang databases. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) was performed to assess the quality of each article. A random-effects model was used to pool the sensitivity and specificity of the positive likelihood ratio (PLR), negative likelihood ratio (NLR) and, diagnostic odds ratio (DOR) together with the area under the curve (AUC) to evaluate diagnostic values. Seventeen studies comprising 2,214 OS patients and 1,534 healthy humans were included in our meta-analysis. The pooled estimations indicated that the miRNAs had a high accuracy for diagnosing OS, with a sensitivity of 0.82, specificity of 0.88, PLR of 10.96, NLR of 0.20, DOR of 54.55, and AUC of 0.93. Twenty-five miRNAs were differentially expressed in OS, including 17 upregulated and 8 downregulated. These miRNAs were correlated with survival time, tumor size, cell differentiation, tumor node metastasis staging, metastasis, tumor/cell invasion, pathological type, and response to radiotherapy and chemotherapy. Several different miRNAs are expressed in OS, and some of them might be potential biomarkers for the early diagnosis of OS.

Negative pressure wound therapy: Regulating blood flow perfusion and microvessel maturation through microvascular pericytes.

Negative pressure wound therapy (NPWT) has been demonstrated to accelerate wound healing by promoting angiogenesis. However, whether blood flow perfusion is regulated by microvessel maturation and pericytes following NPWT remains unclear, as well as the exact association between pericytes and collagen type IV. The aim of this study was to investigate the relevant association between blood flow perfusion and microvessel maturation and pericytes following NPWT, and to further explore the underlying molecular mechanisms. We also aimed to investigate the association between pericytes and collagen type IV. For this purpose, we created a rat model of diabetic wounds and microvascular blood flow perfusion was detected using a laser Doppler blood perfusion imager. The expression levels of angiogenin-1, tyrosine phosphorylation of tyrosine kinase receptor-2 (Tie-2), α-smooth muscle actin (α-SMA) and collagen type IV were detected and analyzed through immunohistochemistry, immunofluorescence, RT-qPCR and western blot analysis. The results revealed that NPWT promoted the overexpression of angiogenin-1, Tie-2, α-SMA and collagen type IV, and significantly increased blood flow perfusion coupled with microvessel maturation in the NPWT group at the later stages (7-10 days) of wound healing. Our results suggested that NPWT can preferentially enhance vessel maturation and increase the number of pericytes, thus regulating blood flow perfusion. On the other hand, pericytes and collagen type IV had a mutual interaction, promoting microvessel maturation.

Comparative effectiveness study between negative pressure wound therapy and conventional wound dressing on perforator flap at the Chinese tertiary referral teaching hospital.

BACKGROUND: Perforator flap techniques with conventional wound dressing have being extensively used in the management of soft-tissue defects. However; the flap's survival rate is not always guaranteed and the wound healing time always long. The aim of this study was to investigate the clinical effectiveness use of a freshly transplanted perforator flap in conjunction with Vacuum-assisted closure (VAC) for better clinical outcomes. METHODS: A prospective, randomized, effectiveness study comparing the clinical outcomes of VAC versus traditional wrap and bandages for the treatment of open wounds that required hospital admission and operative debridement using perforator flaps, was carried out from March 1, 2014 to March 31, 2016 at Wuhan University Zhongnan Hospital. Fifty-one eligible patients were randomized into two groups; study group (perforator flaps covered by VAC) and control group (perforator flaps covered by traditional wrap and bandages). The measured clinical endpoints included the time of the first post-operative dressing change, pain visual analogical scale, perforator flap infection rate, 95% perforator flap healing time and percentage of survived perforator flap. RESULTS: There was no statistically significant difference in the demographic profiles in the two cohorts. There were statistically significant differences in the clinical endpoints in the two groups (p < 0.001; p < 0.05, Table 2). CONCLUSIONS: In summary, VAC combining with perforator flap technique, can diminish accumulated exudation of the transferring flap, protect against postoperative infection, prolong the interval between perforator flap relocation and first postoperative dressing change, decrease pain during removal of dressing, increase perforator flap survival rate, and shorten wound healing time, with a good aesthetic outcome, a good mobility and a satisfactory therapeutic result.

Flow-Through Free Fibula Osteocutaneous Flap in Reconstruction of Tibial Bone, Soft Tissue, and Main Artery Segmental Defects.

OBJECTIVE: The aim of this report was to present the use of flow-through free fibula osteocutaneous flap for the repair of complex tibial bone, soft tissue, and main artery segmental defects. PATIENTS AND METHODS: Five patients with bone, soft tissue, and segmental anterior tibial artery defects were included. The lengths of injured tibial bones ranged from 4 to 7 cm. The sizes of impaired soft tissues were between 9 × 4 and 15 × 6 cm. The lengths of defect of anterior tibial artery segments ranged from 6 to 10 cm. Two patients had distal limb perfusion problems. Flow-through free fibula osteocutaneous flap was performed for all 5 patients. RESULTS: Patients were followed for 12 to 18 months. All wounds healed after 1-stage operation, and all flow-through flaps survived. The distal perfusion after vascular repair was normal in all patients. Superficial necrosis of flap edge was noted in 1 case. After the local debridement and partial thickness skin graft, the flap healed uneventfully, and the surgical operation did not increase injury to the donor site. Satisfactory bone union was achieved in all patients in 2 to 4 months postoperation. Enlargement of fibula graft was observed during follow-up from 12 to 18 months. The functions of adjacent joints were recovered, and all patients were able to walk normally. CONCLUSIONS: Flow-through free fibula osteocutaneous flap was shown to be an effective and efficient technique for repairing composite tibial bone, soft tissue, and main artery segmental defects. This 1-stage operation should be useful in clinical practice for the treatment of complex bone, soft tissue, and vessel defects.

Combined negative pressure wound therapy with open bone graft for infected wounds with bone defects: An experimental study.

BACKGROUND: Bone and soft-tissue defects in infected wound have been an intractable problem to many surgical consultations. Infected wounds with bone defects are physical and financial burden to society. Nowadays, infected wounds with compound defect of bone and soft tissues are common in orthopedics department. Currently, no simple and efficient treatment has been found to solve this problem. This study investigates the effects of combining negative pressure wound therapy (NPWT) with open bone graft on this focus. MATERIALS AND METHODS: Twenty four rabbits with bone and soft tissue defects accompanied infected wounds were randomized into experimental (combined NPWT with open bone graft) and contrast group (only open bone graft). Treatment efficacy was assessed by the wound condition; wound healing time, bacterial bioburden, and bony callus were evaluated by X-ray. Furthermore, samples of granulation tissue from wounds on the 3rd, 7th, and 14th days of healing were evaluated for blood vessels and expression of vascular endothelial growth factor. RESULTS: Wounds in the experimental group tended to have shorter healing time, healthier wound conditions, lower bacterial bioburden, better bony callus, and more blood supply than those in the controlled group. CONCLUSIONS: In conclusion, NPWT combined open bone graft can act as a feasible and valuable method to treat combined infected bone and soft-tissue defects.

HIF-1α inhibits IDH-1 expression in osteosarcoma.

Recently, hypoxia inducible factor-1 (HIF-1) was reported to be correlated with isocitrate dehydrogenase 1 (IDH-1) in several types of tumors. However, the expression and significance of HIF-1 and IDH-1 in osteosarcoma is still unknown. In the present study, the expression levels of IDH-1 and HIF-1α in 35 formalin-fixed paraffin-embedded sections from osteosarcoma patients were investigated by immunohistochemistry. The expression levels of IDH-1 and HIF-1α in human osteosarcoma cell lines (MG-63 and 143B) were further detected by western blotting under normal and hypoxic conditions. In addition, HIF-1α was downregulated via lentiviral vector­mediated RNA interference (RNAi) in the MG-63 human osteosarcoma cell line. The results revealed that HIF-1α was negatively correlated with IDH-1 in the osteosarcoma tissues. Both in MG-63 and 143B cell lines, the expression of HIF-1α was increased while IDH-1 was decreased under a hypoxic condition compared to normal conditions. HIF-1α downregulation promoted IDH-1 expression in the MG-63 cell line under either normal or hypoxic conditions. In conclusion, our findings suggest that HIF-1α inhibits IDH-1 in osteosarcoma and consequently increases the incidence of osteosarcoma.

Circulating fibrocyte mobilization in negative pressure wound therapy.

Non-healing diabetic wounds are difficult to treat. They also create heavy financial burdens for both patients and society. Negative pressure wound therapy (NPWT) has been adopted to treat intractable wounds and has proved to be effective. However, the mechanisms that underlie the effects of this treatment are not entirely understood. Circulating fibrocytes are unique haematopoietic-derived stem cells that have been reported to play a pivotal role in wound healing. Here, we have investigated the effect of NPWT on fibrocyte mobilization and the role of fibrocyte mobilization in the healing of diabetic wounds during NPWT. We show that the NPWT group exhibited 2.6-fold to 12.1-fold greater numbers of tail vein-injected PKH-26-labelled fibrocytes in the diabetic wound sites compared with the control group. We also demonstrate that the full-thickness skin wounds treated with NPWT exhibit significantly reduced mRNA and protein expression, blood vessel density and proliferating cells when exogenous fibrocyte mobilization is inhibited. We speculate that systemic mobilization of fibrocytes during NPWT may be a mechanism for healing intractable wounds in a diabetic rat model experiment and that enhancement of cell mobilization may represent a potential treatment idea for intractable wound healing across all fields of surgery.