[Soft tissue reconstruction strategy for sacral tumor resection].

Objective: To investigate the clinical strategy and effect of soft tissue reconstruction after sacral tumor resection in different planes. Methods: The data of 27 consecutive patients who underwent primary or secondary sacral tumor resection and soft tissue reconstruction from June 2012 to June 2021 at Dongnan Hospital of Xiamen University (the 909th Hospital) were retrospectively analyzed. There were 11 males and 16 females, aged (M(IQR)) (46.2±23.6) years (range: 16 to 72 years). Sacrospinous muscle, gluteus maximus and vertical rectus abdominis muscle flap were selected for soft tissue reconstruction according to the tumor site and the size of tissue defect. the postoperative follow-up was performed. The operative methods, intraoperative conditions, complications and disease outcomes were summarized. Results: Among the 27 patients with sacral tumor, the tumor plane was located in S1 in 8 cases, S2 in 5 cases and S3 or below in 14 cases. There were 12 patients with tumor volume≤400 cm3 and 15 patients with tumor volume>400 cm3. Operation time was 100(90) minutes (range: 70 to 610 minutes), intraoperative blood loss was 800(1 600) ml (range: 400 to 6 500 ml). Soft tissue reconstruction was performed by transabdominal rectus abdominis transfer repair in 2 cases, extraperitoneal rectus abdominis transfer repair in 1 case, gluteus maximus transfer repair in 5 cases, gluteus maximus advancement repair in 13 cases, and sacrospinous muscle transfer repair in 6 cases. Postoperative complications occurred in 6 cases, including 1 case of incision infection, 4 cases of skin border necrosis, and 1 case of delayed infection due to fracture of internal fixator 3 years after operation, all of them were cured. The follow-up time was (35±21) months. Among the patients, 6 patients had recurrence, 2 patients with Ewing sarcoma died of lung metastasis 1 year after operation, 4 patients with metastatic cancer died of primary disease, and the remaining patients survived without disease. Conclusion: Choosing different soft tissue reconstruction strategies according to sacral tumor location and tissue defect size can effectively fill the dead space after sacral tumor resection, reduce postoperative complications and improve the prognosis of patients.

[Research advances on the mechanism of nerve regeneration-related protein in skin fibrosis].

The healing process after skin injury is a dynamic process of interaction between various cells, cytokines, and extracellular matrix. Fibrosis is one of the main ways of skin injury repair. The process of fibrosis involves the regulation of many factors. Studies have shown that nerve regeneration-related protein (NREP) plays a key role in the fibrosis of skin tissue and organs. Based on the mechanism of skin fibrosis, this paper discusses the construction of tertiary structure of NREP, summarizes the effects of NREP and different cells in the skin on skin fibrosis and the research progress of mechanism of NREP in skin fibrosis, thus providing new ideas for the treatment of skin fibrosis diseases.

[Clinical effects of antibiotic bone cement combined with free anterolateral thigh flap in sequential treatment of diabetic foot ulcer].

Objective: To investigate the clinical effects of antibiotic bone cement combined with free anterolateral thigh flap in sequential treatment of diabetic foot ulcer (DFU) wounds. Methods: A retrospective observational study was conducted. From August 2018 to August 2021, 15 patients with DFU who met the inclusion criteria were admitted to the Affiliated Hospital of Zunyi Medical University, including 12 males and 3 females, aged 42-65 years, with a history of type 2 diabetes for 5-19 years. All the wounds of patients were complicated with local bone, muscle, or tendon defects or exposure. The wounds were covered with antibiotic bone cement after debridement in stage Ⅰ+free anterolateral thigh chimeric perforator flap (perforator flap+muscle flap) or simple free anterolateral thigh flap grafting in stage Ⅱ. The defect area of the wound after bone cement removal and debridement was 9.0 cm×5.0 cm-20.0 cm×7.0 cm, the incision area of the flap was 10.0 cm×5.0 cm-22.0 cm×7.0 cm, and the incision area of the muscle flap was 5.0 cm×3.0 cm-8.0 cm×4.0 cm. The donor sites of flaps were sutured directly. During follow-up, the situations of donor site healing and flap survival were observed. At the last follow-up, the texture and shape of the flap, the presence of new ulcers on both limbs, and the walking ability of the patient were observed. Results: During the follow-up of 8 to 21 months after operation in stage Ⅱ, the donor sites healed well with only residual linear scar; flaps in 14 patients survived completely, and the flap in 1 patient developed partial necrosis at 3 weeks after stage Ⅱ surgery, which was healed after debridement and skin grafting. At the last follow-up, the flaps were good in texture and appearance, there were no new ulcers in the affected limb or opposite limb, and the patients had no obvious impairment in daily walking function. Conclusions: To repair DFU wounds with antibiotic bone cement combined with free anterolateral thigh flap can rapidly control the infection, achieving a high survival rate of flap after operation with no obvious impairment in daily walking function of patients.

[Clinical effects of superficial temporal artery lobulated perforator flaps in repairing skin and soft tissue defects after temporal tumor resection].

Objective: To explore the feasibility and clinical effects of using superficial temporal artery lobulated perforator flaps in repairing skin and soft tissue defects after tumor resection in the temporal region. Methods: A retrospective observational study method was used. From March 2017 to October 2022, ten patients with temporal skin tumors were admitted to the Affiliated Hospital of Zunyi Medical University, including six women and four men, with age ranging from 42 to 87 years. Among them, three patients had squamous cell carcinoma and seven patients had basal cell carcinoma, with disease duration ranging from 6 months to 5 years. All temporal tumors underwent expanded resection, leaving wound areas of 5.4 cm×4.2 cm to 7.0 cm×4.0 cm after tumor resection. Superficial temporal artery frontal branch flaps with areas of 5.5 cm×1.2 cm to 7.0 cm×1.5 cm, superficial temporal artery descending branch flaps with areas of 4.2 cm×3.5 cm to 5.0 cm×4.0 cm, and superficial temporal artery parietal branch flaps with areas of 4.2 cm×1.0 cm to 5.0 cm×1.0 cm were designed to repair the wounds and reconstruct the hairline. The donor areas of the flaps were closed and sutured directly. The survival of the flaps was observed on 3 to 5 days after surgery, and the healing of wounds on the donor and recipient sites was observed when the stitches were removed on 5 to 7 days after surgery. During follow-up after surgery, the appearance of the temporal area, scar hyperplasia, hairline reconstruction, and tumor recurrence were observed in the temporal region on the affected side. Results: All the flaps survived well on 3 to 5 days after surgery, and all the donor and recipient site wounds healed well on 5 to 7 days after surgery. During follow-up of 3 to 6 months after surgery, the surgical incisions were concealed; the flaps were not swollen, with a consistent color to the surrounding skin; there were no obvious hypertrophic scars; the reconstructed hairline on the affected side was not significantly different from that of the healthy side; there was no tumor recurrence in the local area. Conclusions: For large areas of skin and soft tissue defects in the temporal region, the use of superficial temporal artery lobulated perforator flaps can repair the wounds in different regions and suture the donor sites in the primary stage simultaneously. The surgical operation is simple, and the facial appearance conforms to the aesthetic requirement after surgery with no tumor recurrence in the local area but a good repair effect. This method is particularly suitable for repairing large areas of skin and soft tissue defects in the temporal region in elderly patients.

[Clinical application effects of two longitudes three transverses method in perforator location of thoracodorsal artery perforator flap and deep wound repair].

Objective: To explore the clinical application value of two longitudes three transverses method in the location of the perforator of thoracodorsal artery perforator and deep wound repair. Methods: The retrospectively observational study was conducted. From December 2018 to June 2020, 17 patients with deep wounds who were admitted to the Affiliated Hospital of Zunyi Medical University met the inclusion criteria and were included in this study, including 7 males and 10 females, aged 12 to 72 years. The wound areas of patients after debridement were 7 cm×3 cm to 11 cm×7 cm. Two longitudinal lines were located through the midpoint of the armpit, the posterior superior iliac spine, and the protruding point of the sacroiliac joint, and three transverse lines were located 5, 10, and 15 cm below the midpoint of the armpit between the two longitudinal lines, i.e. two longitudes three transverses method, resulting in two trapezoidal areas. And then the thoracodorsal artery perforators in two trapezoidal areas were explored by the portable Doppler blood flow detector. On this account, a single or lobulated free thoracodorsal artery perforator flap or flap that carrying partial latissimus dorsi muscle, with an area of 7 cm×4 cm to 12 cm×8 cm was designed and harvested to repair the wound. The donor sites were all closed by suturing directly. The number and location of thoracodorsal artery perforators, and the distance from the position where the first perforator (the perforator closest to the axillary apex) exits the muscle to the lateral border of the latissimus dorsi in preoperative localization and intraoperative exploration, the diameter of thoracodorsal artery perforator measured during operation, and the flap types were recorded. The survivals of flaps and appearances of donor sites were followed up. Results: The number and location of thoracodorsal artery perforators located before operation in each patient were consistent with the results of intraoperative exploration. A total of 42 perforators were found in two trapezoidal areas, with 2 or 3 perforators each patient. The perforators were all located in two trapezoid areas, and a stable perforator (the first perforator) was located and detected in the first trapezoidal area. There were averagely 1.47 perforators in the second trapezoidal area. The position where the first perforator exits the muscle was 2.1-3.1 cm away from the lateral border of the latissimus dorsi. The diameters of thoracodorsal artery perforators were 0.4-0.6 mm. In this group, 12 cases were repaired with single thoracodorsal artery perforator flap, 3 cases with lobulated thoracodorsal artery perforator flap, and 2 cases with thoracodorsal artery perforator flap carrying partial latissimus dorsi muscle. The patients were followed up for 6 to 16 months. All the 17 flaps survived with good elasticity, blood circulation, and soft texture. Only linear scar was left in the donor area. Conclusions: The two longitudes three transverses method is helpful to locate the perforator of thoracodorsal artery perforator flap. The method is simple and reliable. The thoracodorsal artery perforator flap designed and harvested based on this method has good clinical effects in repairing deep wound, with minimal donor site damage.

Clinical characteristics and biomarkers of breast cancer associated with choline concentration measured by 1H MRS.

This study investigated the association between the total choline (tCho) concentration and the clinical characteristics and biomarker status of breast cancer. Sixty-two patients with breast cancer, 1.5 cm or larger in size on MR images, were studied. The tCho concentration was correlated with the MRI features, contrast enhancement kinetics, clinical variables and biomarkers. Pairwise two-tailed Spearman's nonparametric test was used for statistical analysis. The tCho concentration was higher in high-grade than moderate-/low-grade tumors (p = 0.04) and in tumors with higher K(trans) and k(ep) (p < 0.001 for both). The association of tCho concentration with age (p = 0.05) and triple negative biomarker (p = 0.09) approached significance. tCho was not detected in 17 patients, including 15 with invasive ductal cancer and two with infiltrating lobular cancer. Fifteen of the 17 patients had moderate- to low-grade cancers, and 11 had human epidermal growth factor-2-negative cancer, suggesting that these two factors might lead to false-negative choline. Higher tCho concentration in high-grade tumors and tumors with higher K(trans) and k(ep) indicates that choline is associated with cell proliferation and tumor angiogenesis. The higher choline level in younger women may be caused by their more aggressive tumor type. The results presented here may aid in the better interpretation of (1)H MRS for the diagnosis of breast lesions.

[Macrophage migration inhibitory factor meditates MPP+/MPTP-induced NLRP3 inflammasome activation in microglia cells].

OBJECTIVE: To explore the mechanisms of macrophage migration inhibitory factor (MIF)/nucleus factor-κB (NF-κB) in mediating 1-methyl-4-phenylpyridinium iodide (MPP +)/1-Methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced activation of Nod-like receptor protein 3 (NLRP3) inflammasome in microglials and the its effects on neurons. METHODS: Murine microglial cell line Bv-2 was infected with a lentivirus carrying MIF shRNA for MIF knockdown and then treated with MPP+. The total protein levels of NLRP3, caspase-1, p65 and p65 in the cell nuclei and cytoplasm were detected. ELISA was used to detect the levels of IL-1ß and IL-18 in the culture supernatant, which served as the conditioned culture medium for MN9D cells, whose TH expression level was detected using Western blotting. The effect of stereotactic injection of an adeno-associated virus (AAV) carrying MIF shRNA on behaviors was assessed in a C57BL/6 mouse model of Parkinson disease (PD) induced by intraperitoneal MPTP injection. TH and Iba-1 immunohistochemistry was used to evaluate the number of substantia nigra neurons and the activation of microglia cells, and the protein expressions of MIF, NLRP3 and TH in the substantia nigra were detected with Western blotting. RESULTS: MPP+ significantly increased NLRP3 and MIF expressions in Bv-2 cells (P < 0.05). MIF knockdown in Bv-2 cells significantly lowered NLRP3 and caspase-1 protein expressions and IL-1ß and IL-18 levels in the culture supernatant (P < 0.05) without affecting total protein level of p65. Bv-2 cells with MIF knockdown showed significantly lowered p65 protein expression in the nuclei but increased p65 expression in the cytoplasm (P < 0.05). The conditioned medium derived from Bv-2 cells with MIF knockdown, as compared with that from than MPP +-treated Bv-2 cells, significantly increased TH expression in MN9D cells (P=0.01). Compared with those in MPTP group, the mice receiving injections of AAV-MIF-shRNA had higher scores in pole test and open field test with lower scores in traction test, and showed increased TH-positive neurons, decreased Iba-1 microglia cell activation, reduced expressions of MIF and NLRP3, and increased expression of TH in he substantia nigra (all P < 0.05). CONCLUSION: Inhibition of MIF can reduce the expression of NLRP3 inflammasomes and inflammatory factor caused by MPP+ in microglia cells to relieve the damage of dopaminergic neurons and alleviate microglia cell activation, thus offering protection against neuroinflammation in Parkinson's disease.

Fabrication of biodegradable magnesium matrix composite with ultrafine grains and high strength by adding TiC nanoparticles to Mg-1.12Ca-0.84Zn-0.23Mn (at.%) alloy.

Mg-1.12Ca-0.84Zn-0.23Mn (at.%) alloy was reinforced by TiC nanoparticles. After extrusion ultra-fine grains of ∼0.4 µm were caused by Zener pinning effect of nano-sized particles including fine precipitated MgZn2 phases, α-Mn particles and TiC nanoparticles. Yield strength of 423.6 MPa along with ultimate tensile strength of 436.8 MPa could meet biomedical application.

The Comparison in the Microstructure and Mechanical Properties between AZ91 Alloy and Nano-SiCp/AZ91 Composite Processed by Multi-Pass Forging Under Varying Passes and Temperatures.

In this study, both AZ91 alloy and nano-SiCp/AZ91 composite were subjected to multi-pass forging under varying passes and temperatures. The microstructure and mechanical properties of the alloy were compared with its composite. After six passes of multi-pass forging at a constant temperature of 400 ℃, complete recrystallization occurred in both the AZ91 alloy and composite. The decrease of temperature and the increase of passes for the multi-pass forging led to further refinement of dynamic recrystallized grains and dynamic precipitation of second phases. The grain size of the nano-SiCp/AZ91 composite was smaller than that of the AZ91 alloy under the same multi-pass forging condition, which indicated that the addition of SiC nanoparticles were beneficial to grain refinement by pinning the grain boundaries. The texture intensity for the 12 passes of multi-pass forging with varying temperatures was increased compared with that after nine passes. The ultimate tensile strength is slightly decreased while the yield strength was increased unobviously for the AZ91 alloy with the decrease of temperature and the increase of the passes for the multi-pass forging. Under the same condition of multi-pass forging, the yield strength of the composite was higher than that of the AZ91 alloy due to the Orowan strengthening effect and grain refinement strengthening resulting from externally applied SiC nanoparticles and internally precipitated second phases. By comparing the microstructure and mechanical properties between the AZ91 alloy and nano-SiCp/AZ91 composite, the strength-toughness properties of the composites at room temperature were affected by the matrix grain size, texture evolution, SiC nanoparticles distribution and the precipitated second phases.

[Effects of free mini-flap on tibial side of third toe on repairing skin and soft tissue defect of finger pulp at the end of finger].

Objective: To investigate the effects of free mini-flap on tibial side of third toe on repairing skin and soft tissue defect of finger pulp at the end of finger. Methods: From August 2013 to May 2017, 18 patients with skin and soft tissue defect of finger pulp at the end of finger were admitted to our unit, with 12 men and 6 women aged 16 to 54 years. As the skin and soft tissue defect sites, there were 3 cases of thumb, 8 cases of index finger, 4 cases of middle finger, and 3 cases of ring finger. The area of defects ranged from 2.0 cm×1.4 cm to 3.5 cm×2.4 cm. Free mini-flaps on tibial side of third toes were designed according to area and shape of defects, and the length and width of flaps were 0.1 to 0.2 cm longer than the length and width of the defects, respectively. The area of flaps ranged from 2.1 cm×1.5 cm to 3.7 cm×2.6 cm. The end-to-end anastomosis of subcutaneous veins of flaps and superficial veins of the finger-palm side or superficial dorsal digital vein, the end-to-end tension-free anastomosis of the base metatarsal arteries on tibial side of third toe and proper digital arteries of recipient finger were performed. Besides, anastomosis of base metatarsal nerve on tibial side of third toe and proper digital nerve of recipient finger was performed. The donor sites on feet were sutured directly or repaired with full-thickness skin grafts on medial upper leg of the same side. The survival of flaps after operation and the follow-up of patients were observed. Results: All flaps survived well, with good blood supply. Among the 18 patients, 2 patients lost to follow-up, and 16 patients were followed up for 4 to 36 months. The shape and texture of flaps were good. After reconstruction, finger pulps at the end of finger were plump, with fingerprint. Function of the finger restored well, and the two-point discriminatory distances of flaps were 5 to 10 mm. The donor sites on feet of 14 patients healed after the operation, the other 2 patients had necrosis on edge and central area of skin grafts, and the necrotic area healed after dressing change. The skin graft areas on feet were wear-resistant, with slight damage to donor sites and did not influence shoes wearing and walking. Besides, patients did not feel uncomfortable. Conclusions: Skin and soft tissue defects of finger pulp at the end of finger repaired by free mini-flaps on tibial side of third toe are with good shape and slight damage to donor sites, and the operation is simple. It is worthy of popularization and application in clinic.

[Effects of combined transplantation of rat Schwann cells and fibroblasts on nerve regeneration of denervated perforator flaps in rats and the mechanism].

Objective: To explore the effects of combined transplantation of the rat Schwann cells and fibroblasts (Fbs) on the nerve regeneration of denervated perforator flaps in rats and the mechanism. Methods: (1) Fbs were isolated from the trunk of 2 Sprague-Dawley (SD) rats embryos of 14-16 days' pregnancy and cultured, and the morphology of the cells was observed. The third passage of cells were used for subsequent experiments. The protein expressions of fibronectin and Ephrin-B2 were observed by immunohistochemical method. The mRNA expression of Ephrin-B2 was detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction (n=3). (2) Schwann cells were isolated from the bilateral sciatic nerves and brachial plexus nerves of 45 SD rats born for 1-3 days and cultured, and the morphology of the cells was observed. The third passage of cells were used for subsequent experiments. The rate of S100 positive cells was detected by immunofluorescence method and flow cytometer, with sample numbers of 9 and 3 respectively. (3) In Dulbecco's modified Eagle medium (DMEM) high glucose medium, 1 mL Fbs and 1 mL Schwann cells both in the concentration of 1×10(5) cells/mL were co-cultured as Schwann cells+ Fbs co-culture group, and 2 mL Schwann cells in the concentration of 1×10(5) cells/mL were cultured alone as Schwann cells alone culture group, with 5 wells in each group. The clusters of Schwann cells in the two groups were observed and counted under inverted phase contrast microscope at post culture hour (PCH) 6 and 24 respectively. The clusters of Schwann cells in Schwann cells+ Fbs co-culture group were observed by immunofluorescence method at PCH 24 too. The protein expressions of EphB2, Sox2, and N-cadherin in Schwann cells of two groups at PCH 24 were detected by Western blotting (n=20). (4) Totally 100 8-week-old male SD rats were selected, and an in situ replanted peritoneal denervated perforator flap was made in each rat. According to the random number table, the rats were divided into simple flap group, Fbs alone transplantation group, Schwann cells alone transplantation group, Schwann cells+ Fbs co-transplantation group, with 25 rats in each group. Flaps of rats in Fbs alone transplantation group and Schwann cells alone transplantation group were injected with 0.4 mL Fb and 0.4 mL Schwann cells respectively (2×10(6) cells each). Flaps of rats in Schwann cells+ Fbs co-transplantation group were injected with 0.4 mL Fbs and Schwann cells mixed cells (totally 2×10(6) cells, cell number ratio: 1∶1), and flaps of rats of simple flap group were injected with the same volume of DMEM high glucose medium. On post injection day (PID) 2, 5, 7, 9, and 14, 5 rats in each group were selected respectively according to the random number table. The flap tissue was collected, and the number, diameter, and arrangement of regenerated nerves were observed by immunofluorescence method. Data were processed with completely random designed t test, analysis of variance for repeated measurement, t test, and Bonferroni correction. Results: (1) The third passage of cells isolated and cultured from the rat embryo trunks were uniform in size and shape, long spindle-shaped, with a large proportion of nuclei. Strong positive expressions of fibronectin and Ephrin-B2 protein in cells were observed, and the mRNA expression of Ephrin-B2 was 0.004 1±0.000 8. The cells were identified as Fbs. (2) After 5 days of culture, the primary cells isolated from the sciatic nerves and brachial plexus nerves of neonatal rats were elongated in cell bodies and grew in nest, fence, or vortex-like shape. The third passage of cells were detected by immunofluorescence method and flow cytometer, and the corresponding S100 positive cell rates were (95.9±1.0)% and (95.8±1.1)% respectively. The cells were identified as Schwann cells. (3) At PCH 6 and 24, the cluster numbers of Schwann cells in Schwann cells+ Fbs co-culture group were significantly higher than those of Schwann cells alone culture group (t=6.500, 10.614, P<0.01). At PCH 24, the Schwann cells in Schwann cells+ Fbs co-culture group aggregated into clusters, Fbs dispersed around the Schwann cell clusters, and the protein expressions of EphB2, N-cadherin, and Sox2 in Schwann cells were significantly higher than those in Schwann cells alone culture group (t=2.975, 19.717, 11.159, P<0.05 or P<0.01). (4) On PID 2, a small number of scattered, disordered, short, and thin nerve fibers were observed in the flap tissue of rats in the four groups. From PID 5 to 14, the number of nerve fibers in the flap tissue of rats of Schwann cells+ Fbs co-transplantation group increased gradually, and the nerve fibers were with long diameter and arranged orderly. The number of nerve fibers in the flap tissue of rats of Schwann cells alone transplantation group increased, but the nerve fibers were with short diameter and arranged disorderly, and the number was smaller than that of Schwann cells+ Fbs co-transplantation group. In simple flap group and Fbs alone transplantation group, the nerve fibers in the flap tissue of rats gradually degenerated with gradually decreased number or even disappeared. Conclusions: The combined transplantation of Fbs and Schwann cells in rats can regulate Schwann cells migration and clustering by activating Ephrin/Eph-Sox2-N-cadherin signaling pathway, thus promoting the orderly nerve regeneration of denervated perforator flaps in rats.

Clicky hip alone is not a true risk factor for developmental dysplasia of the hip.

AIMS: A clicky hip is a common referral for clinical and sonographic screening for developmental dysplasia of the hip (DDH). There is controversy regarding whether it represents a true risk factor for pathological DDH. Therefore a 20-year prospective, longitudinal, observational study was undertaken to assess the relationship between the presence of a neonatal clicky hip and pathological DDH. PATIENTS AND METHODS: A total of 362 infants from 1997 to 2016 were referred with clicky hips to our 'one-stop' paediatric hip screening clinic. Hips were assessed clinically for instability and by ultrasound imaging using a simplified Graf/Harcke classification. Dislocated or dislocatable hips were classified as Graf Type IV hips. RESULTS: The mean age at presentation was 13.8 weeks (12.8 to 14.7). In all 351 out of 362 children (97.0%) had Graf Type I hips (normal) that required no treatment. Nine children (2.5%) had Graf Type II hips but all resolved to Graf Type I hips on follow-up scans. One child (0.3%) had Graf Type III hip dysplasia and one child (0.3%) had an irreducible hip dislocation. The two pathological hips were associated with unilateral limited hip abduction. Mean referrals increased from 12.9 to 23.3 each year (p = 0.002) from the first decade of the study to the second, driven by increasing primary care referrals (5.5 versus 16.7 per year, p < 0.001). CONCLUSION: Most clicky hips required no treatment other than reassurance to parents. Clicky hips with a normal hip examination should be considered a variant of normal childhood and not a risk factor for DDH. However, an abnormal hip examination including unilateral limited hip abduction should prompt urgent further investigations. Cite this article: Bone Joint J 2017;99-B:1533-6.

[Clinical effects of middle and low peroneal artery perforator flap with pedicle on repairing skin and soft tissue defects of ankle].

Objective: To investigate clinical effects of middle and low peroneal artery perforator flap with pedicle on repairing skin and soft tissue defects of ankle. Methods: Twenty patients with skin and soft tissue defects of ankle and exposure of tendon and bone were admitted in our burn wards from April 2012 to December 2015. The size of skin and soft tissue defects ranged from 5 cm×4 cm to 23 cm×10 cm. Patients were treated with debridement and vacuum sealing drainage (VSD) after admission. After VSD treatment for 1 week, flap transplantation operation was performed. Middle and low perforating branches of peroneal artery were detected by portable Doppler blood flow meter before the operation. Flaps were designed and resected according wounds during the operation, with 1 or 2 middle and low perforating branches of peroneal artery in flaps. Seventeen patients were treated with middle and low peroneal artery perforator flap. Larger wounds with exposure of tendon and bone were repaired with middle and low peroneal artery perforator flap, and the other wounds were repaired with intermediate split-thickness skin graft of thigh on the same side in three patients. The size of flap ranged from 6 cm×5 cm to 25 cm×12 cm. The donor sites were sutured directly or repaired with intermediate split-thickness skin graft of thigh on the same side. Results: After operation, 1 patient with partial skin necrosis at the distal of the flap because of disorder of venous circulation healed after dressing change and physiotherapy, and flaps of the other 19 patients survived well. During follow-up of 3 to 36 months, flaps of all patients were in good appearance, with no obvious cicatrix, and the affected limbs and ankle joints functioned well. Conclusions: Middle and low peroneal artery perforator flap with advantages of stable perforating branch, reliable blood supply, and large resected size, can repair skin and soft tissue defects of ankle.

EBV-miR-BHRF1-2 targets PRDM1/Blimp1: potential role in EBV lymphomagenesis.

PRDM1/Blimp1, a master regulator of B-cell terminal differentiation, has been identified as a tumor suppressor gene in aggressive lymphomas, including diffuse large B-cell lymphoma (DLBCL). It has been shown in DLBCL and Hodgkin lymphoma that PRDM1 is downregulated by cellular microRNAs. In this study, we identify the Epstein-Barr virus (EBV) microRNA (miRNA), EBV-miR-BHRF1-2, as a viral miRNA regulator of PRDM1. EBV-miR-BHRF1-2 repressed luciferase reporter activity by specific interaction with the seed region within the PRDM1 3' untranslated region. EBV-miR-BHRF1-2 inhibition upregulated PRDM1 protein expression in lymphoblastoid cell lines (LCL), supporting a role of miR-BHRF1-2 in PRDM1 downregulation in vivo. Discordance of PRDM1 messenger RNA and protein expressions is associated with high EBV-miR-BHRF1-2 levels in LCLs and primary post-transplant EBV-positive DLBCL. Enforced expression of PRDM1-induced apoptosis and cell cycle arrest in LCL cells. Inhibition of EBV-miR-BHRF1-2 negatively regulates cell cycle and decreases expression of SCARNA20, a small nucleolar RNA that is also downregulated by PRDM1 overexpression. The interaction between EBV-miR-BHRF1-2 and PRDM1 may be one of the mechanisms by which EBV-miR-BHRF1-2 promotes EBV lymphomagenesis. Our results support the potential of EBV-miR-BHRF1-2 as a therapeutic target in EBV-associated lymphoma.

Treatment field shape verification using elliptic Fourier transform.

An automated field shape correlation technique based on elliptic Fourier transform (EFT) is developed to verify the radiation treatment field in digital portal images. In this method, the edge of the treatment field is initially extracted from the portal image and is then approximated by a polygon. The polygon is further represented with elliptic Fourier coefficients. The invariants to shift, rotation, and scale are computed from the elliptic Fourier coefficients to characterize the genuine shape feature and are used to match the reference treatment field. Invariants calculated from both test and reference field shapes are compared to determine the similarity between two treatment fields. The proposed procedure uses the first approved field shape as the reference for automated comparison with subsequent portal images. This technique not only verifies the shape of each portal field but also provides information about relative shift, rotation, and scale. A set of generic shapes is simulated to test the robustness of the algorithm and to determine the parameters used in the decision procedure. Experimental results on the simulated shapes show that this method can detect shape distortions of 2% in area and the standard deviations are 0 for shifting, 0.24 degrees for rotation, and 0.0031 for scaling. Preliminary tests on clinical portal images indicated that this technique is potentially useful for automated real-time portal verification.

The effect of detector size to the broadening of the penumbra--a computer simulated study.

The effect of detector size to the broadening of the measured beam penumbra has been a subject of numerous studies. Based on measured data, linear and quadratic curves have been proposed to describe the relationship between the measured penumbra width, between 10%-90% and 20%-80% intensities, and the detector size. Extrapolations of these curves to zero detector size also suggest that the inherent penumbras can be deduced. However, due to experimental noise, especially when a small ionization chamber is used, and the inherent penumbra is not known, it is difficult to discern the superiority of either model. In this study, one dimensional convolution using a thin circular disk shape detector was employed to analyze the effect of detector size to the broadening of the penumbra. A set of beams with different inherent penumbra widths, ranging from 0 to 350 in arbitrary unit, was first generated. Each beam was then convoluted with the response function of the detectors with different sizes from 10 to 280, in arbitrary unit. The result is an output signal with penumbra that is wider than the inherent penumbra. The plots of penumbra widths to detector radii are a family of concave parabolic curves with different inherent penumbra widths. The concave portions of the curve represent results from scanning with detectors equal to or smaller than the penumbra width, and the linear portions represent results from scanning with detectors much larger than the penumbra. The curves are nothing but different scales of one curve. The extrapolations of the curves to the penumbra axis when the detector radius approaches zero give the deduced inherent penumbra widths. The deduced inherent penumbra widths approximate the inherent penumbra widths satisfactorily. From the graphs provided, the inherent penumbra can be deduced using the detector radius and the measured penumbra width.

A novel speech-processing strategy incorporating tonal information for cochlear implants.

Good performance in cochlear implant users depends in large part on the ability of a speech processor to effectively decompose speech signals into multiple channels of narrow-band electrical pulses for stimulation of the auditory nerve. Speech processors that extract only envelopes of the narrow-band signals (e.g., the continuous interleaved sampling (CIS) processor) may not provide sufficient information to encode the tonal cues in languages such as Chinese. To improve the performance in cochlear implant users who speak tonal language, we proposed and developed a novel speech-processing strategy, which extracted both the envelopes of the narrow-band signals and the fundamental frequency (F0) of the speech signal, and used them to modulate both the amplitude and the frequency of the electrical pulses delivered to stimulation electrodes. We developed an algorithm to extract the fundatmental frequency and identified the general patterns of pitch variations of four typical tones in Chinese speech. The effectiveness of the extraction algorithm was verified with an artificial neural network that recognized the tonal patterns from the extracted F0 information. We then compared the novel strategy with the envelope-extraction CIS strategy in human subjects with normal hearing. The novel strategy produced significant improvement in perception of Chinese tones, phrases, and sentences. This novel processor with dynamic modulation of both frequency and amplitude is encouraging for the design of a cochlear implant device for sensorineurally deaf patients who speak tonal languages.