MicroRNA­186­5p downregulation inhibits osteoarthritis development by targeting MAPK1.

As a chronic degenerative joint disease, the characteristics of osteoarthritis (OA) are degeneration of articular cartilage, subchondral bone sclerosis and bone hyperplasia. It has been reported that microRNA (miR)­186­5p serves a key role in the development of various tumors, such as osteosarcoma, non­small­cell lung cancer cells, glioma and colorectal cancer. The present study aimed to investigate the effect of miR­186­5p in OA. Different concentrations of IL­1ß were used to treat the human chondrocyte cell line CHON­001 to simulate inflammation, and CHON­001 cell injury was assessed by detecting cell viability, apoptosis, caspase-3 activity and the levels of TNF­α, IL­8 and IL­6. Subsequently, reverse transcription­quantitative PCR was performed to measure miR­186­5p expression. The results demonstrated that following IL­1ß treatment, CHON­001 cell viability was suppressed, apoptosis was promoted, the caspase-3 activity was significantly enhanced and the release of TNF­α, IL­8 and IL­6 was increased. In addition, IL­1ß treatment significantly upregulated miR­186­5p expression in CHON­001 cells. It was also identified that MAPK1 was a target gene of miR­186­5p, and was negatively regulated by miR­186­5p. miR­186 inhibitor and MAPK1­small interfering RNA (siRNA) were transfected into CHON­001 cells to investigate the effect of miR­186­5p on CHON­001 cell injury induced by IL­1ß. The results demonstrated that miR­186 inhibitor suppressed the effects of IL­1ß on CHON­001 cells, and these effects were reversed by MAPK1­siRNA. In conclusion, the present results indicated that miR­186­5p could attenuate IL­1ß­induced chondrocyte inflammation damage by increasing MAPK1 expression, suggesting that miR­186­5p may be used as a potential therapeutic target for OA.

Tripaddle Posterior Interosseous Artery Flap Design for 3-Finger Defects: An Evaluation of 3 Surgical Approaches.

INTRODUCTION: The tripaddle posterior interosseous artery (PIA) flap can be used for multifinger defect resurfacing, but interpatient variations in perforator distribution remain an ongoing challenge when using this approach. This study aims to evaluate the efficacy of 3 different tripaddle PIA perforator flap designs according to the PIA perforator distribution for the repair of 3-finger defects. METHODS: In accordance with the size of the 3-finger defects and the position of the perforators, a tripaddle flap was designed on the multiple perforators of the descending branch of the PIA in the distal two thirds of the forearm. Patients received 1 of 3 distinct tripaddle PIA perforator flap designs based on perforator distributions of the PIA. RESULTS: Three cases of 3-finger defects were repaired with type A trefoil-shaped tripaddle flaps, whereas 4 cases were repaired with type B modified trefoil-shaped tripaddle flaps, and the other 3 cases were repaired with type C chain-shaped tripaddle flaps. All flaps survived except 2 paddles with tip necrosis. After 9.1 months of mean follow-up, 9 of the 10 cases demonstrated satisfactory cosmetic appearance, whereas the last case required a debulking procedure in the second stage. CONCLUSIONS: The free tripaddle PIA perforator flap is an effective option for repairing 3-finger skin defects. Various flap designs based on the PIA perforator distribution allow for more individualized treatment approaches.

Use of Free Modified Innervated Posterior Interosseous Artery Perforator Flap to Repair Digital Skin and Soft Tissue Defects.

Current techniques to reconstruct soft tissue of the fingers result in scarring and functional deficits. Perforator flaps raised on the posterior interosseous artery are thin and well vascularised, and cause minimal donor site scarring. Using a flap with sensory nerves was hoped to contribute to the desired postoperative sensory recovery of fingers. We used modified innervated posterior interosseous perforator flaps to repair digital defects in 18 patients. Injuries included digit amputations and palmar soft tissue defects. The posterior antebrachial cutaneous nerve was carried in the flap and bridged with the defect section of the proper digital nerve. The flaps used measured 10 cm × 6 cm to 5 cm × 3 cm. All 18 flaps survived; one necrotic edge eventually healed. During the 10-28 months of follow-up (average, 14 months), two-point discrimination in flaps and injured fingers was 6-15 mm. Good functional and sensory outcomes were obtained in primary operation, and patients were generally satisfied with the aesthetic results. Further work will be needed to assess the branches of the posterior interosseous artery preoperatively to improve surgical planning.

Modified Innervated Radial Collateral Artery Perforator Flap for Repairing Digital Defects.

The authors presented their clinical experience and demonstrated surgical methods to reconstruct soft-tissue defects in the digit by using modified innervated radial collateral artery perforator flap. Surgical procedures that involved 12 modified innervated radial collateral artery perforator flaps were performed in 12 patients. Among the patients, two had defects in the thumbs, six had defects in the index fingers, whereas two had defects in the middle fingers, two had defects in the little fingers. The flaps ranged in size from 5.0 × 2.0 to 7.5 × 4.0 cm. The pedicle of the flap was divided and ligated below the level at which the radial collateral artery was divided into anterior and posterior branches. The recipient vessels were the proper digital artery and the palmar subcutaneous vein (n = 8), the deep branch of the ulnar palm artery (n = 4), and the venae comitantes. Nerve suture was done between the posterior cutaneous nerve of the arm and the proper digital nerve of the digital. The cosmetic appearance of the donor and recipient sites and static two-point discrimination of the operated finger were evaluated in a follow-up visit. Postoperative venous congestion happened in two cases, and both succeeded after exploration. All flaps survived, and all donor sites were closed directly, leaving a linear scar. Follow-up time ranged from 12 to 28 months. Defatting of the flap was performed in two cases during the late postoperative period. Cosmetically acceptable results were achieved for the rest of the patients. The modified innervated radial collateral artery perforator flap is a good option for reconstructing soft-tissue defects in digits.

Free multilobed posterior interosseous artery perforator flap for multi-finger skin defect reconstruction.

BACKGROUND: The posterior interosseous artery (PIA) perforator flap can be used for reconstruction of soft-tissue defects of fingers. Based on the multiple perforators from the posterior interosseous artery, we describe a technique to reconstruct the multi-finger defect in the use of the free multilobed PIA perforator flap. METHODS: PIA perforators from different areas of the forearm were used to design a free multilobed skin paddle for multi-finger skin defect reconstruction. Each paddle without the deep fascia had separate perforators. To increase the perforator pedicle length, the courses of the PIA perforators were dissected from the superficial layer of the deep fascia to the subcutaneous layer. RESULTS: The flap was raised as a unilateral free bilobed PIA perforator flap in 10 cases of two-finger defects, a free trilobed PIA perforator flap in two cases of three-finger defects, and a bilateral free bilobed PIA perforator flap in one case of four-finger defects. The average effective vascular pedicle length and trunk pedicle length were 8.3 and 3.1 cm, respectively, for the bilobed flap, and 6.3 and 4.0 cm, respectively, for the trilobed flap. All flaps survived except one paddle with tip necrosis. At 10.8 months (range, 4-27 months) after surgery, 10 cases showed satisfactory cosmetic appearance, while the fingers were bulky in the remaining three cases. The average score of static two-point discrimination in 10 innervated paddles was 12.9 mm. The remaining 20 paddles recovered only protective sensation. The average total active motion (TAM) of each finger was 164° before surgery and 187° at the latest follow-up. CONCLUSIONS: Free multilobed PIA perforator flap is a good candidate for reconstruction of multi-finger skin defect. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, Ⅳ.

Modified chimeric radial collateral artery perforator flap for repairing hand composite defects.

BACKGROUND: The authors presented their clinical experience and demonstrated surgical methods for reconstructing complex bone and soft tissue defects of the hand by using modified chimeric radial collateral artery perforator flaps. METHODS: Surgical procedures that employed 16 modified chimeric radial collateral artery perforator flaps and 3 dual paddle flaps were performed in 16 patients. Among the patients, eight had defects in the metacarpal bones and eight had defects in the phalanx bones. The flaps were created with a skin paddle and humeral bone segments by using independent perforators. The flaps ranged in size from 5.5 × 2.0 to 7.5 × 4.5 cm, whereas the humeral fragments ranged in size from 1.5 × 0.5 to 4.0 × 1.5 cm. The pedicle of the flaps was divided and ligated below the level at which the radial collateral artery separates into anterior and posterior branches. The recipient vessels were the proper digital artery, the palmar subcutaneous vein (n = 12), the deep branch of the palmar ulnar artery (n = 4), and the venae comitantes. The cosmetic appearance of both donor and recipient sites was evaluated during a follow-up visit. RESULTS: Postoperative venous congestion occurred in two cases. The venous obstruction was reanastomosed after venous thrombectomy. The procedures were successful in both cases upon examination. All the flaps survived and all the donor sites were closed directly, leaving only a linear scar. Follow-up time ranged from 12 to 28 months. Bone components achieved union in all cases at an average of 5.4 months (ranging from 3 to 6 months). In two cases, the flap was defatted during the late postoperative period. Cosmetically acceptable results were achieved for the rest of the patients. CONCLUSION: The modified chimeric radial collateral artery perforator flap is a good alternative for reconstructing complex bone and soft tissue defects of the hands. LEVEL OF EVIDENCE: This is a level IV, retrospective series.

Electrical stimulation by semi-implantable electrodes decreases the levels of proteins associated with sciatic nerve injury-induced muscle atrophy.

Muscle atrophy is a disease that is usually caused by denervation. The aim of the present study was to determine whether electrical stimulation by semi-implantable electrodes is capable of decreasing the levels of specific proteins associated with sciatic nerve injury-induced muscle atrophy. Male Sprague Dawley (SD) rats with damaged sciatic nerves were maintained on a 12­h light/dark cycle. Thirty-two SD rats were randomly allocated into 4 groups (each group, n=8). The rats in group C received no electrical stimulation; the rats in groups D, N and DN received electrical stimulation by semi-implantable electrodes during the daytime alone, nighttime alone and both the daytime and nighttime, respectively. Immunoblot assays were performed to detect the expression of cellular proteins associated with muscle atrophy. The number of muscle satellite cells was determined using a microscope, indicating that electrical stimulation increased the number of muscle satellite cells. Immunoblot assay results showed that electrical stimulation reduced the expression levels of cathepsin L, calpain 1 and the ubiquitinated muscle ring finger­1 (MuRF-1) protein. In conclusion, electrical stimulation by semi-implantable electrodes constitutes a potential method for the treatment of sciatic nerve injury-induced muscle atrophy. The decreased expression levels of the cellular proteins cathepsin L and calpain 1, as well as the ubiquitinated protein MuRF-1, are associated with the attenuation of sciatic nerve injury-induced muscle atrophy.