Objective To detect the msr gene which confers resistance to erythromycin, and ana-lyze its distributing difference between the two biovars of Ureaplasma urealyticum. Methods Broth dilution method was used to determine the minimum inhibitory concentrations (MIC) to erythromycin among 72 U. urealyticum clinical isolates. The msrA, msrB, msrC and msrD genes detection and biotyping of U. urea-lyticum were conducted using PCR. Results The MICs of 72 U. urealyticum isolates to erythromycin ranged from ≤0. 125 μg/ml to ≥128 μg/ml. MIC_(50) was 32 μg/ml and MIC_(50) was ≥128 μg/ml. Biotyping showed that biovar Parvo had 51 strains (51/72, 70.83%) and biovar T960 had 21 (21/72, 29.17%) strains.The msrA, msrB, msrC and msrD genes were obtained in 1, 12, 0 and 24 strains, respectively, with five strains carrying the msrB and msrD genes, and one strain carrying the msrA, msrB and msrD genes. There was no resistance difference to erythromycin between the two biovars when the MIC≥8 μg/ml was considered resistance to eryt hromycin. But the msrB gene was predominantly detected in biovar T960. Conclusion U. urealyticum clinical isolates harbeur the msrA, msrB and msrD genes, and the predominantly detected msrB gene is of biovar T960.

Objective To study the relationship between erythromyein sensitivity and ermB gene in 143 Ureaplasma urealyticum (Uu) clinical isolates. Methods We detected the minimum inhabit concen-trations (MICs) of Uu to erythromycin by broth dilution method and MIC≥8 μg/ml was used as standard concentration of resistance to erythromycin. Polymerase chain reaction was used to detect the ermB gene and biotype Uu with primers based on multi-band antigen gene. Results The MICs, MIC50 MIC90 of Uu to erythromycin were ≤0. 125 μg/ml to ≥128 μg/ml, 16 μg/ml, and ≥128 μg/ml, respectively, with a high resistance rate of 64.38%. ermB gene, which was mainly detected in Uu with MIC≥8 μg/ml, was positively detected in 40 out of 143 Uu strains (27.97%). No significant differences of the resistance to erythromycin and positive rate of ermB gene were found between the two biovars in the study . Conclusion ermB gene may probably be one of the important genes conferring resistance to erythromycin in Uu. Further studies are needed to discover the difference of resistance and mechanism of erythromycin between the two bi-ovars.

Objective To study the resistance mechanism of Ureaplasma urealyticum (Uu) to erythromycin.Methods The susceptibility of 73 clinical isolates of Uu to erythromycin was evaluated by using broth dilution techniques. PCR and DNA sequencing were carried out to screen hot spot mutations at the variable region of 23S ribosomal RNA in erythromycin-resistant strains of Uu. Moreover, erythromycin resistance methylase genes (ermA, ermB, ermC) and efflux pump genes (mefA/E, msrA/B, mreA) were screened by using PCR with specific primers. Results There were 35 (47.95%) resistant Uu strains out of the 73 isolates, and the minimal inhibitory concentration varied from 8 to 32 mg/L among these resistant strains. The ermB gene was detected in 19 (54.29%) resistant strains, and msrA/B gene in 9 (25.71%) resistant strains. Two resistant strains harbored both ermB gene and msrA/B gene. No mutation at 23S ribosomal RNA or amplification of resistance-associated genes was noted in sensitive or reference strains of Uu. Conclusion The ermB and msrA/B genes may be responsible for the erythromycin resistance of Uu.

Objective: To investigate the feasibility and technical tips of repairing facial defects with pre-expanded propeller flap based on the perforators of the supratrochlear artery or the supraorbital artery. Methods: In the first-stage operation, a tissue expander was buried underneath the frontalis muscle. The second-stage operation was conducted using pre-expanded supratrochlear artery or the supraorbital artery based propeller flap to repair facial defect. Results: From July 2010 to July 2016, this method was used in 8 patients. 5 flaps were based on the supratrochlear artery, and 3 flaps based on the supraorbital artery. Expander size was ranged from 150 ml to 300 ml. The size of propeller flaps was from 10 cm × 6 cm to 15 cm × 13 cm. All the flaps survived without any major complications. Follow-up period ranged from 3 to 36 months. Eyebrow replacement, flap thinning and scar revision were performed in 6 cases. All patients were satisfied with the final aesthetic result. Conclusions The pre-expanded propeller flap based on the supratrochlear artery or the supraorbital artery is an alternative option to repair the facial defect in appropriate cases.

Objective: To propose a classification method and explore the indications and technical tips of the pedicled deep inferior epigastric artery perforator (DIEAP) flap. Methods: From July 2005 to December 2017, 18 patients underwent soft-tissue defect repairment using the pedicled DIEAP flap. The defect locations included abdomen (n=6), iliolumbar region (n=2), perineum (n=4), and proximal thigh (n=6). The flaps were divided into two types. The type Ⅰ flap were further subdivided into two subtypes. The type Ⅰa flap was solely based on the DIEAP. The type Ⅰb flap was also based on the DIEAP, however, the main trunk of the deep inferior epigastric vessels needs to be divided to further improve the pedicle length. The type Ⅱ flap was the traditional pedicled DIEAP flap. Results: Twenty flaps were included in this series. The mean flap size and pedicle length of the 4 flaps in type Ⅰa were 19.0 cm× 6.5 cm and 2.88 cm respectively. The rotation angles were 60 degrees (n=1), 120 degrees (n=1), and 180 degrees (n=2). The 3 flaps of type Ⅰb was 26 cm × 6 cm, 20 cm × 5 cm and 24 cm × 7 cm in size, and the pedicle lengths of them were 6 cm, 7 cm and 7 cm, respectively. All flaps in this subtype were rotated by 180 degrees. The mean flap size and pedicle length of the 13 type Ⅱ flaps were 21.46 cm × 9.38 cm and 11.08 cm. 17 flaps completely survived postoperatively. Small-sized necrosis of the distal portion of the flap occurred in 3 flaps. All patients were followed up for 6 months to 5 years, with the averaged 11 months follow-up time. All patients were satisfied with the final outcomes. Tumor recurrence was not noticed for the oncological patients. Conclusions The pedicled DIEAP flap has remarkable versatility in the defect repairment for the regions including abdomen, iliolumbar region, proximal thigh, and perineal region. Combining with the " propeller flap" concept, the clinical application of pedicled DIEAP flap could be further expanded. The pedicled DIEAP flap is a reliable reconstructive method for defect repairment in abdominal and iliolumbar regions.

Objective: To explore the clinical effects of scapular region flaps pedicled with circumflex scapular artery in the reconstruction of axillary burn scar contractures. Methods: From December 2008 to December 2018, 21 patients with axillary burn scar contractures were admitted to our department. There were 12 male patients and 9 female patients, aged 2-48 years, with an average of 17.4 years. According to the characteristics of axillary scar contractures, the patients were divided into type Ⅰ of 5 patients, type Ⅱ of 2 patients, type Ⅲ of 5 patients, and type Ⅳ of 9 patients. The preoperative abduction ranges of shoulder joint were 20-150°, with an average of 68.33°. The wound areas after resection and release of scar contractures ranged from 12 cm×4 cm to 33 cm×11 cm, with an average of 18.13 cm×5.41 cm, and the wounds were repaired with scapular region flaps pedicled with circumflex scapular artery in the areas of 14 cm×5 cm-35 cm×14 cm, with an average of 20.19 cm×7.71 cm. The donor sites of 5 patients were expanded prior to flap repair operation, and the other 16 patients were repaired by direct transfer of flaps. The donor sites were closed directly. The type, number, and transfer way of scapular region flaps were calculated, and the improvement of abduction angle of shoulder joint and condition of the flaps were observed during follow-up after operation. Results: There were 5 ascending scapular flaps, 13 scapular flaps, and 3 parascapular flaps. The flaps were transferred through open wounds in 18 cases, subcutaneous tunnel in 1 case, and trilateral foramia in the remaining 2 cases. All the flaps survived after operation. During follow-up of 3 months to 5 years, with an average of 19.4 months, the abduction angles of shoulder joints were 90-180°, with an average of 137.62°, which showed that the abduction function of shoulder joint improved obviously. The texture of flap was soft, and the color of the flap was close to the surrounding skin. The patients and/or their family members were satisfied with the operation results. Conclusions The scapular region flap pedicled with circumflex scapular artery has a lot of advantages, including a long vascular pedicle, simple technique for flap harvest, a hidden donor site, and flexible and diverse transfer mode of flap. It is an effective option for clinical reconstruction of severe axillary burn scar contracture.

Objective: To explore the feasibility and technical tips of defect reconstruction using the pre-expanded perforator propeller (PEPP) flap. Methods: From July 2009 to December 2017, 56 patients underwent defect reconstruction using the PEPP flap. During the first-stage operation, an expander with appropriate size was buried within a soft-tissue pocket. Three strategies were used for expander placement, including placement of the expander underneath the muscle, at a distance from the emergence point of the perforator when the perforator location is relatively fixed, and following the criteria when a free-style perforator flap is designed. At the second-stage operation, a PEPP flap was raised and rotated a certain number of degrees to reconstruct the defect. Results: 56 flaps were elevated. The expanders were buried according to the strategy Ⅰ in 2 cases, the strategy Ⅱ in 42 cases, and the strategy Ⅲ in 12 cases. The flap size ranged from 7-13 cm to 14-32 cm with the average size of 9.38 cm × 21.22 cm. The pedicle length ranged from 2.5 cm to 10 cm and the mean length was 5.03 cm. The rotation angle was 180 degrees in 44 cases, 150 and 120 degrees in 6 cases respectively. The perforators that were previously explored were all identified during the second-stage operation. 53 flaps survived completely. Venous congestion of the distal portion of the flap was observed after the surgery in two cases. Necrosis of small area of the flap occurred and free skin grafting was used to resurface the defect after debridement. All patients were followed up for 3 months to 4 years and the average follow-up time was 13.4 months. Conclusions The PEPP flap can not only ensure primary closure of the donor site, but also provide more extra tissue for defect reconstruction. For selected patients, it could be an alternative option for soft-tissue defect reconstruction.

Objective:To explore the feasibility and technical tips of donor-site reconstruction of the latissimus dorsi myocutaneous flap using the perforator propeller flap technique.Methods:Between July 2012 and January 2019, a total of 24 patients, including 9 males and 15 females, underwent reconstructions of defects in various locations using the latissimus dorsi myocutaneous flap. The average patient age was 43.6 years (range, 4-81 years). Before surgery, perforators adjacent to the latissimus dorsi muscle were explored using an ultrasound Doppler probe and marked on the skin. A latissimus dorsi myocutaneous flap was elevated according to the resultant defect following the removal of the lesion and transferred to reconstruct the defect. The donor-site defects were reconstructed using one, dual, or even triple perforator propeller flap.Results:All the 24 myocutaneous flaps survived completely. The dimension and width of the myocutaneous flaps ranged from 16 cm × 11 cm to 33 cm × 17 cm and 9 cm to 20 cm, respectively. The donor-site defects of the myocutaneous flap were all closed by perforator propeller flaps including 22 pedicled flaps and 2 free flaps. The defect was reconstructed by one perforator propeller flap in 12 patients, two flaps in 11, and three flaps in the remaining one patient. There were 36 posterior intercostal artery perforator propeller flaps and one freestyle perforator propeller flap. The size, pedicle length, and rotation angle of the propeller flaps were 13 cm × 5 cm to 23 cm × 14 cm, 3 cm to 6 cm, and 90 to 180 degrees, respectively. All the donor sites of the perforator propeller flaps were closed primarily. Total necrosis of the propeller flap occurred in one patient and small-sized distal flap necrosis in another one. The remaining propeller flaps survived completely. All patients were followed up for one to 38 months and the mean follow-up time was 7 months. Tumor recurrence was noticed in four patients. All patients were satisfied with the final functional and aesthetic outcomes.Conclusions:Using the perforator propeller flaps could guarantee not only harvesting a wide latissimus dorsi myocutaneous flap, but also primary donor-site closure of the myocutaneous flap, and therefore greatly improve the versatility and capability of the latissimus dorsi myocutaneous in defect reconstruction.

Objective:To explore the indications and technical tips of defect reconstruction in the elbow and upper arm using the radial collateral artery perforator (RCAP) propeller flap.Methods:From October 2016 to December 2019, 6 patients underwent defect reconstruction using the RCAP propeller flaps. All patients were female, aged from 5 to 66 years, with an average of 31 years. All of the defects were repaired with radial collateral artery perforator propeller flap. Before the surgery, the RCAP was thoroughly explored using the hand-held ultrasound Doppler and marked on the skin. According to the size, shape and location of the defect, a RCAP propeller flap was elevated based on the chosen RCAP, rotated in a certain degree with the perforating point as the rotation point. The large paddle was used to repair the defect of the upper extremity, and the small paddle was used to assist in closing the donor site. The donor sites were sutured directly or repaired with free skin graft. Capillary filling test or indocyanine green SPY fluorescence imaging system was used to evaluate the blood supply of the flap immediately. The effect was observed.Results:The defect size ranged from 6.0 cm × 3.0 cm to 10.0 cm × 7.0 cm. The flap size ranged from 6.0 cm × 3.5 cm to 20.0 cm × 8.0 cm. All perforators were septocutaneous perforators. The pedicle of the pedicle ranged from 2.5 cm to 5.0 cm and the mean length was 3.6 cm. The flaps were rotated 180° in 5 patients, and 150° in one patient. The donor sites were sutured directly in 5 patients and repaired with free skin graft in one patient. Five flaps survived completely without any major complications. Wound infection occurred in one flap, which healed after debridement. All donor sites were closed primarily, except one which was covered by free skin grafting. All patients were followed up for 3 months to 3 years and the average follow-up time was 2.4 years. The appearance and texture of the flap were good, and the motion of elbow joint was normal. All patients were satisfied with the functional and aesthetic outcomes of the upper extremities. Tumor recurrence was not noticed in the oncologic patients.Conclusions:For selected patients, the RCAP propeller flap could be an alternative option for soft-tissue defect reconstruction in the upper extremity.

Since the first description by Hyakusoku in 1991, perforator propeller flaps have become one of the most commonly used method for defect reconstruction across the entire human body. We briefly reviewed the history, definition, nomenclature, and classification of perforator propeller flaps, and the corresponding surgical techniques were introduced in detail as well by reviewing our clinical cases. The clinical applications of the perforator propeller flaps were reviewed thoroughly by describing its use in different anatomic regions including the head and neck, trunk, extremities, buttock, and perineum respectively. Both the advantages and drawbacks of the flaps, common complications, and its prevention were also analyzed. Problems that we often encountered in the application of perforator propeller flaps and its current research status were analyzed and summarized. Although the perforator propeller flaps have been increasingly widely used, there still exist some important issues that deserve more concern and need to be solved, including precise perforator localization, accurate definition of perforators, correlations between the rotation angle of the flap, vascular patency and pedicle length. Though with the aforementioned problems, we believe that, like the tissue expansion and microsurgical flap transfer technique, the perforator propeller flap technique will ultimately become a conventional and important method for defect and organ reconstruction.