[Multicenter retrospect analysis of early clinical features and analysis of risk factors on prognosis of elderly patients with severe burns].

Objective: To investigate the early clinical characteristics of elderly patients with severe burns and the risk factors on prognosis. Methods: This study was a retrospective case series study. Clinical data of 124 elderly patients with severe burns who met the inclusion criteria and were admitted to the 12 hospitals from January 2015 to December 2020 were collected, including 4 patients from the Fourth People's Hospital of Dalian, 5 patients from Fujian Medical University Union Hospital, 22 patients from Guangzhou Red Cross Hospital of Jinan University, 5 patients from Heilongjiang Provincial Hospital, 27 patients from the First Affiliated Hospital of Naval Medical University, 9 patients from the First Affiliated Hospital of Nanchang University, 10 patients from Affiliated Hospital of Nantong University, 9 patients from Tongren Hospital of Wuhan University & Wuhan Third Hospital, 12 patients from the 924th Hospital of PLA, 6 patients from Zhangjiagang First People's Hospital, 4 patients from Taizhou Hospital of Zhejiang Province, and 11 patients from Zhengzhou First People's Hospital. The patients' overall clinical characteristics, such as gender, age, body mass index, total burn area, full-thickness burn area, inhalation injury, causative factors, whether combined with underlying medical diseases, and admission time after injury were recorded. According to the survival outcome within 28 days after injury, the patients were divided into survival group (89 cases) and death group (35 cases). The following data of patients were compared between the two groups, including the basic data and injuries (the same as the overall clinical characteristics ahead); the coagulation indexes within the first 24 hours of injury such as prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time, D-dimer, fibrinogen degradation product (FDP), international normalized ratio (INR), and fibrinogen; the blood routine indexes within the first 24 hours of injury such as white blood cell count, platelet count, neutrophil-to-lymphocyte ratio, monocyte count, red blood cell count, hemoglobin, and hematocrit; the organ function indexes within the first 24 hours of injury such as direct bilirubin, total bilirubin, urea, serum creatinine, aspartate aminotransferase, alanine aminotransferase, total protein, albumin, globulin, blood glucose, triglyceride, total cholesterol, alkaline phosphatase, creatine kinase, electrolyte indexes (potassium, sodium, chlorine, calcium, magnesium, and phosphorus in blood), uric acid, myoglobin, and brain natriuretic peptide; the infection and blood gas indexes within the first 24 hours of injury such as procalcitonin, C-reactive protein, pH value, oxygenation index, base excess, and lactate; treatment such as whether conducted with mechanical ventilation, whether conducted with continuous renal replacement therapy, whether conducted with anticoagulation therapy, whether applied with vasoactive drugs, and fluid resuscitation. The analysis was conducted to screen the independent risk factors for the mortality within 28 days after injury in elderly patients with severe burns. Results: Among 124 patients, there were 82 males and 42 females, aged 60-97 years, with body mass index of 23.44 (21.09, 25.95) kg/m2, total burn area of 54.00% (42.00%, 75.00%) total body surface area (TBSA), and full-thickness burn area of 25.00% (10.00%, 40.00%) TBSA. The patients were mainly combined with moderate to severe inhalation injury and caused by flame burns. There were 43 cases with underlying medical diseases. The majority of patients were admitted to the hospital within 8 hours after injury. There were statistically significant differences between patients in the 2 groups in terms of age, total burn area, full-thickness burn area, and inhalation injury, and PT, APTT, D-dimer, FDP, INR, white blood cell count, platelet count, urea, serum creatinine, blood glucose, blood sodium, uric acid, myoglobin, and urine volume within the first 24 hours of injury (with Z values of 2.37, 5.49, 5.26, 5.97, 2.18, 1.95, 2.68, 2.68, 2.51, 2.82, 2.14, 3.40, 5.31, 3.41, 2.35, 3.81, 2.16, and -3.82, respectively, P<0.05); there were statistically significant differences between two groups of patients in whether conducted with mechanical ventilation and whether applied with vasoactive drugs (with χ2 values of 9.44 and 28.50, respectively, P<0.05). Age, total burn area, full-thickness burn area, serum creatinine within the first 24 hours of injury, and APTT within the first 24 hours of injury were the independent risk factors for the mortality within 28 days after injury in elderly patients with severe burns (with odds ratios of 1.17, 1.10, 1.10, 1.09, and 1.27, 95% confidence intervals of 1.03-1.40, 1.04-1.21, 1.05-1.19, 1.05-1.17, and 1.07-1.69, respectively, P<0.05). Conclusions: The elderly patients with severe burns had the injuries mainly from flame burns, often accompanied by moderate to severe inhalation injury and enhanced inflammatory response, elevated blood glucose levels, activated fibrinolysis, and impaired organ function in the early stage, which are associated with their prognosis. Age, total burn area, full-thickness burn area, and serum creatinine and APTT within the first 24 hours of injury are the independent risk factors for death within 28 days after injury in this population.

[Echocardiographic two-dimensional strain evaluation of right ventricular function in healthy adults].

Objective: To explore the feasibility of using two-dimensional speckle tracking echocardiography for measuring right ventricular strain and function in healthy adults, and to analyze the impact of age and gender. Methods: This study is a cross-sectional study. Healthy adults who underwent physical examination in the Physical Examination Center of Beijing Hospital from January 1, 2020 to January 1, 2021 were included. Two researchers independently measured various right ventricular longitudinal strain indices using the Echopac software, including (global longitudinal strain (GLS), apical longitudinal strain (ALS), midventricle longitudinal strain (MLS), basal longitudinal strain (BLS), free wall GLS (FWGLS), free wall ALS (FWALS), free wall MLS (FWMLS) and free wall BLS (FWBLS)) as well as tricuspid annular plane systolic excursion (TAPSE) and right ventricle-fraction of area change (RVFAC). The above indicators were taken as the average of two physicians. The consistency of the measurements by two physicians was evaluated by the within-group correlation coefficient (ICC). Results: A total of 233 subjects were included, including 137 males, aged (58.5±14.2) years. ICC values was all above 0.8 with excellent agreement. The values of FWGLS and GLS in healthy adults were -26.63% and -21.89%, respectively. There was no statistically significant difference in TAPSE ((2.06±0.41)cm vs. (2.10±0.39)cm, P=0.510) and RVFAC ((51.17±9.91)% vs. (50.89±8.65)%, P=0.826) between males and females. The values of various right ventricular long axis strain indicators (GLS, ALS, MLS, BLS, FWGLS, FWMLS, FWMLS, FWBLS) in females aged 18 to 40 and 41 to 65 years were higher than those in males of the same age (all P<0.05), while there was no statistically significant difference in the values of various right ventricular long axis strain indicators between the sexes in subjects aged 65 years and above (all P>0.05). In females, the right ventricular GLS, ALS, MLS, FWGLS, FWALS, FWMLS, and FWBLS values in the groups aged 18 to 40 and 41 to 65 years were significantly higher than those in the group aged 65 years and above (all P<0.05). In contrast, no significant differences were found in these indices among different age groups in males (all P>0.05). Conclusions: Using two-dimensional speckle tracking technology in echocardiography to measure right ventricular strain indicators is feasible and highly reproducible. Gender and age have an impact on right ventricular strain indicators.

[Effects of artificial dermis combined with autologous skin in repairing the wounds with exposed bone and/or tendon in fingers of children after electric burns].

Objective: To explore the effects of artificial dermis combined with autologous skin in repairing the wounds with exposed bone and/or tendon in fingers of children after electric burns. Methods: A retrospective observational study was conducted. From January 2017 to December 2022, 14 children with bone and/or tendon exposed wounds in fingers after electric burns who met the inclusion criteria were admitted to Zhengzhou First People's Hospital, including 9 males and 5 females, aged 2 to 11 years. A total of 38 fingers were affected, with 1 wound per finger. After debridement, artificial dermal coverage combined with vacuum sealing drainage was performed in all the wounds in the first stage, with wound area of 2.0 cm×1.0 cm-4.5 cm×2.5 cm after debridement. The second stage surgery was performed to close the wound with autologous thin intermediate thickness skin graft. Then the children were told to perform functional rehabilitation exercise as early as possible. The survival of autologous skin graft was observed at the 7th day after the second stage surgery. The wound healing time was recorded. After 12 months of follow-up, the Vancouver scar scale was used to evaluate the scar hyperplasia at the skin grafting site of the affected finger; the total action mobility (TAM) of the affected finger joint was measured for evaluating the functional recovery of the affected finger; a self-made efficacy satisfaction rating table was used to investigate the parents' satisfaction with the curative effect of the children. Results: At the 7th day after the second stage surgery, all the children had good survival of autologous skin grafts. The wound healing time was (24.1±2.7) d. After 12 months of follow-up, the scar score at the skin grafting site of the affected finger was 5.2±2.4; the TAM of the affected finger joint was (177±40)°; the functional assessment was good in 12 fingers, medium in 23 fingers, and poor in 3 fingers; the parents' satisfaction with the curative effect of the children in the survey was very satisfied in 10 cases, satisfied in 3 cases, and dissatisfied in 1 case. Conclusions: The combination of artificial dermis and autologous thin intermediate thickness skin graft is an alternative surgical method that can effectively repair the bone and/or tendon exposed wounds in fingers of children after electric burns. After wound healing, the scars are slight, the finger function is well recovered, and the parents of the children are highly satisfied with the curative effect of the children, which is worthy of clinical promotion.

[Effects of free gracilis muscle flap combined with sural nerve transfer for reconstruction of digital flexion and sensory function of hand in patient with wrist electric burn].

Objective: To explore the effects of free gracilis muscle flap combined with sural nerve transfer for reconstruction of digital flexion and sensory function of hand in patient with severe wrist electric burn. Methods: A retrospective observational study was conducted. From January 2017 to December 2020, 4 patients with wrist high-voltage electric burn admitted to the Department of Burns of the First People's Hospital of Zhengzhou and 4 patients with wrist high-voltage electric burn admitted to the Department of Hand Surgery of Beijing Jishuitan Hospital met the inclusion criteria, including 6 males and 2 females, aged 12 to 52 years. They were all classified as type Ⅱ wrist high-voltage electric burns with median nerve defect. In the first stage, the wounds were repaired with free anterolateral thigh femoral myocutaneous flap. In the second stage, the free gracilis muscle flap combined with sural nerve transplantation was used to reconstruct the digital flexion and sensory function of the affected hand in 3 to 6 months after wound healing. The cut lengths of muscle flap and nerve were 32 to 38 and 28 to 36 cm, respectively. The muscle flap donor area and nerve donor area were both closed and sutured. The survival condition of gracilis muscle flap and sural nerve, the wound healing time of recipient area on forearm, the healing time of suture in muscle flap donor area and nerve donor area were observed and recorded after operation, and the recovery of donor and recipient areas was followed up. In 2 years after operation, the muscle strength of thumb and digital flexion and finger sensory function after the hand function reconstruction were evaluated with the evaluation criteria of the hand tendon and nerve repair in the trial standard for the evaluation of functions of upper limbs of Hand Surgery Society of Chinese Medical Association. Results: All the gracilis muscle flap and sural nerve survived successfully after operation. The wound healing time of recipient area on forearm was 10 to 14 days after operation, and the healing time of suture in muscle flap donor area and nerve donor area was 12 to 15 days after operation. The donor and recipient areas recovered well. In the follow-up of 2 years after operation, the muscle strength of thumb and digital flexion was evaluated as follows: 4 cases of grade 5, 3 cases of grade 4, and 1 case of grade 2; the finger sensory function was evaluated as follows: 4 cases of grade S3+, 2 cases of grade S3, and 2 cases of grade S2. Conclusions: For patients with hand dysfunction caused by severe wrist electric burn, free gracilis muscle flap combined with sural nerve transplantation can be used to reconstruct the digital flexion and sensory function of the affected hand. It is a good repair method, which does not cause great damage to thigh muscle flap donor area or calf nerve donor area.

[Curative effects of foot microflap free transplantation in the repair of full-thickness electric burn wounds deep to tendon or even bone in fingers].

Objective: To explore the curative effects of foot microflap free transplantation in the repair of full-thickness electric burn wounds deep to tendon or even bone in fingers. Methods: A retrospective observational study was conducted. From July 2017 to February 2022, 20 patients with full-thickness electric burn wounds deep to tendon or even bone in fingers who met the inclusion criteria were admitted to Zhengzhou First People's Hospital, including 19 males and 1 female, aged 18 to 64 years. Among the 20 wounds, 15 wounds were located on the palm side, including 8 on the thumb, 5 on the index finger, and 2 on the middle finger; 5 wounds were located on the back, including 1 on the index finger and 4 on the middle finger. After debridement, the wound area ranged from 4.5 cm×2.0 cm to 7.0 cm×3.0 cm. According to the principle of tissue structure similarity, 10 wounds were repaired with plantar medial flaps, 5 wounds were repaired with hallux peroneal flaps, and 5 wounds were repaired with dorsalis pedis artery flaps, with flap area of 5.0 cm×2.5 cm-8.0 cm×3.5 cm. The flaps were transplanted freely and arteries and veins and/or nerves were anastomosed at the same time. The wound in the donor site was repaired with thigh medium-thick skin graft. The survival of flaps and skin grafts were observed after surgery. The appearance of flap, temperature and color of the distal end in the affected finger were observed during follow-up. At the last follow-up, the joint function and flap sensory recovery of the affected finger were evaluated with the trial standard for the evaluation of the functions of the upper limbs of the Hand Surgery Society of the Chinese Medical Association; the two-point discrimination distance of skin in the area of flaps with nerve anastomosis was measured; the satisfaction of patients with the curative effect was investigated by using the curative effect satisfaction rating scale, and the very satisfied rate was calculated; the repair effect of flap was evaluated by the comprehensive evaluation scale, and the excellent and good rate was calculated. Results: All the flaps and skin grafts survived after surgery. During the follow-up of 10-18 months after surgery, the appearance of flap was natural and not bloated; the temperature and color of the distal end in the affected finger were basically the same as that of normal finger skin. At the last follow-up, the function recovery of the affected finger joints was as follows: 11 affected fingers were within the normal range of motion, 6 affected fingers had their total active range of motion recovered to 85% of the healthy side, and 3 affected fingers had their total active range of motion recovered to 75% of the healthy side; the flap sensory recovery was as follows: the sense of 15 flaps with nerve anastomosis all recovered to grade S3+, and the two-point discrimination distance of skin in the flap area was 7.0-9.0 mm; the sense of 1 flap without nerve anastomosis recovered to grade S2 and the sense of 4 flaps recovered to grade S1. The satisfaction with curative effect of 20 patients was very satisfied in 16 cases and moderately satisfied in 4 cases, with the very satisfied rate of 80%; the repair result of 20 flaps was excellent in 16 cases, good in 2 cases, and fair in 2 cases, with excellent and good rate of 90%. Conclusions: Due to the similar tissue structure of donor site and recipient site, foot microflap free transplantation in the repair of full-thickness electric burn wounds deep to tendon or even bone in fingers can achieve good appearance and function, with better functional and sensory recovery of the affected finger in the case of nerve anastomosis. Patients have high degree of satisfaction with the curative effects, which is worthy of promotion.

[Curative effects of ultrathin anterolateral femoral flap in one-stage split-finger repair of palmar combined with multiple finger wounds].

Objective: To explore the curative effects of ultrathin anterolateral femoral flap in one-stage split-finger repair of palmar combined with multiple finger wounds. Methods: A retrospective observational study was conducted. From October 2016 to June 2018, 20 patients with wounds on palms and multiple fingers who met the inclusion criteria were admitted to Zhengzhou First People's Hospital, including 15 males and 5 females, aged 18 to 77 years. After debridement, the wound area was 8 cm×4 cm-17 cm×12 cm. The wound was repaired by ultrathin anterolateral femoral flap with area of 9 cm×5 cm to 19 cm×13 cm. According to the wound condition of finger, the finger division was performed in one stage, and the length-to-width ratio of the split-finger flap was 2.0:1.0-2.5:1.0. During the surgery, the descending branches of lateral circumflex femoral artery and accompanying vein of flap were anastomosed end-to-end to the radial artery and vein in the recipient area, respectively, and the anterolateral femoral cutaneous nerve of flap was bridged with the superficial branch of radial nerve in the recipient area. The wounds in the donor area of flap in 14 patients were sutured directly, the wounds in the donor area of flap in 3 patients were repaired by relay superficial iliac circumflex artery perforator flap, and the wounds in the donor area of flap in 3 patients were covered by free trunk medium-thick skin graft. The survival of flap, occurrence of vascular crisis and other complications, and healing of wounds in the donor area of flap were recorded. The appearance of flap, scar hyperplasia in the donor and recipient areas and the patients' satisfaction with the shape and function of the donor and recipient areas were followed up. In 1 year after surgery, the two-point discrimination distance of the flap was measured, and the recovery of hand function was evaluated by the trial standard for the evaluation of the functions of the upper limbs of the Hand Surgery Society of the Chinese Medical Association. Results: The flaps of 17 patients survived without vascular crisis or other complications after surgery. The flap of 1 patient had poor blood circulation and partial necrosis, and the wound was healed 14 days after dressing change and grafting of split-thickness skin graft from head. Two patients had mild cyanosis at the margin of flap after surgery, which disappeared spontaneously 5 days later. Incisions at donor site, relay flaps, and skin grafts of all patients survived well. After surgery, the color and texture of flap were basically the same as that of the normal skin of hand, and linear scars were observed in the donor and recipient areas. The patients were satisfied with the recovery of appearance and function of donor and recipient areas. After 1 year of follow-up, the patients' hand sensory function recovered well, the two-point discrimination distance of flap was 4-6 mm, and the recovery of hand function was evaluated as excellent in 18 cases and good in 2 cases. Conclusions: The ultrathin anterolateral femoral flap in repairing the palmar combined with multiple finger wounds in one-stage split-finger can significantly reduce the number of surgeries and improve the function and beauty of the hand, so it is worthy of clinical promotion.

[Clinical effects of scalp flaps pedicled with superficial temporal artery parietal branch in repairing facial destructive burn wounds].

Objective: To explore the clinical effects of scalp flaps pedicled with superficial temporal artery parietal branch in repairing facial destructive burn wounds. Methods: A retrospective observational study was conducted. From January 2016 to December 2021, 15 patients with facial destructive burns who met the inclusion criteria were admitted to Zhengzhou First People's Hospital, including 11 males and 4 females, aged 22 to 79 years. Two patients were complicated with unilateral eyeball destructive burns, two patients were complicated with unilateral auricle defects, eight patients were complicated with lip and cheek defects, and three patients were complicated with lip, cheek, and unilateral nasal alar defects. The burn wound areas ranged from 9 cm×6 cm to 13 cm×10 cm. The scalp flaps pedicled with superficial temporal artery parietal branch, with the area of 10 cm×7 cm to 15 cm×11 cm, were designed, excised, and transferred for repairing burn wounds. The secondary wounds at the donor sites were repaired with medium-thickness scalp grafts. According to patient's needs, the hairs grew at the facial transplanted flap were removed by laser at 2 weeks after the flap was completely viable, or the expanded scalp flap was used to treat the secondary alopecia in the flap donor area of the head at 3 months after the primary wound repair. The survival of the flap/skin graft and the wound healing of the donor and recipient areas after the primary wound repair were recorded. During the follow-up, the appearance of the flap, the scar hyperplasia at the suture site, the repair effect of facial functional parts, the treatment effects of laser hair removal and secondary alopecia treatment at the flap donor site were observed; the patient's satisfaction with the overall repair effect was inquired. Results: After the primary wound repair, all the flaps transplanted to the burn wounds and the skin grafts transplanted to the secondary wounds of the flap donor sites survived well, and the wounds at the donor and recipient sites of flap healed well. The color, texture, and thickness of flap were basically the same as those of normal facial skin, and the scar at the suture site was slight during 3 to 18 months of follow-up period after the primary wound repair. In 11 patients complicated with lip defects, the oral integrity, and the opening and closing functions of mouth were restored with the mouth opening being 2.0-2.5 cm and no microstomia; all the patients could carry out basic language communication, 8 of them could take regular food, and 3 of them could take soft food. The wounds in two patients with unilateral eyeball destructive burns were repaired. In 2 patients complicated with auricle defects, the wounds were repaired, and the external auditory canals were normal. In 3 patients complicated with unilateral nasal alar defects, their noses had poor appearance with reduced nostrils. No hair growth was observed in the facial flap sites after treatment of laser hair removal in 8 patients. Five patients were successfully treated with expanded scalp flaps for secondary alopecia in the flap donor area of the head. The patients were all satisfied with the overall repair effect. Conclusions: The scalp flap pedicled with superficial temporal artery parietal branch has abundant blood supply and is suitable for repairing the wounds in facial destructive burns. It is easy to transfer and can better restore the appearance and function of the recipient area with minimal damage to the flap donor area, which is worthy of clinical promotion.

[C2 pedicle screw insertion assisted by mobilization of the vertebral artery in cases with high-riding vertebral artery].

Objective: To examine the feasibility, safety, and efficacy of mobilization of the vertebral artery for C2 pedicle screws in cases with high-riding vertebral artery (HRVA). Methods: The clinical data of 12 patients with basilar invagination and atlantoaxial dislocation underwent atlantoaxial reduction and fixation in the Department of Neurosurgery, the First Affiliated Hospital of University of Science and Technology of China between January 2020 and November 2021 were retrospectively analyzed. All patients had high-riding vertebral artery on at least one side that prohibited the insertion of C2 pedicle screws. There were 2 males and 10 females aged (48.0±12.8) years (range: 17 to 67 years). After correction of vertical dislocation during the operation, the C2 pedicle screw insertion and occipitocervical fixation and fusion were performed using the vertebral artery mobilization technique. Neurological function was assessed using the Japanese Orthopedic Association (JOA) scale. The preoperative and postoperative JOA score and the main radiological measurements, including the anterior atlantodental interval (ADI), the distance of the odontoid tip above the Chamberlain line, the clivus-canal angle, were collected and compared by paired t-test. Results: Mobilization of the high-riding vertebral artery was successfully completed, and C2 pedicle screws were then fulfilled after the vertebral artery was protected. There was no injury to the vertebral artery during the operation. Meanwhile, no severe surgical complications such as cerebral infarction or aggravated neurological dysfunction occurred during the perioperative period. Satisfactory C2 pedicle screw placement and reduction were achieved in all 12 patients. All patients achieved bone fusion 6 months after surgery. No looseness and shift in internal fixation or reduction loss was observed during the follow-up period. Compared to the preoperative, the postoperative ADI decreased from (6.1±1.9) mm to (2.0±1.2) mm (t=6.73, P<0.01), the distance of the odontoid tip above the Chamberlain line decreased from (10.4±2.5) mm to (5.5±2.3) mm (t=7.12, P<0.01), the clivus-canal angle increased from (123.4±11.1) ° to (134.7±9.6) ° (t=2.50, P=0.032), the JOA score increased from 13.3±2.1 to 15.6±1.2 (t=6.99, P<0.01). Conclusion: The C2 pedicle screw insertion assisted by mobilization of the vertebral artery is safe and considerably effective, providing a choice for internal fixation in cases with high-riding vertebral arteries.

[A prospective study on the expansion rule of the directional skin and soft tissue expander in abdominal scar reconstruction].

Objective: To observe the expansion rule of directional skin and soft tissue expander (hereinafter referred to as expander) in abdominal scar reconstruction. Methods: A prospective self-controlled study was conducted. Twenty patients with abdominal scar who met the inclusion criteria and admitted to Zhengzhou First People's Hospital from January 2018 to December 2020 were selected by random number table method, including 5 males and 15 females, aged 12-51 (31±12) years, with 12 patients of type Ⅰ scar and 8 patients of type Ⅱ scar. In the first stage, two or three expanders with rated capacity of 300-600 mL were placed on both sides of the scar, of which at least one expander had rated capacity of 500 mL (as the follow-up observation object). After the sutures were removed, water injection treatment was started, with the expansion time of 4 to 6 months. After the water injection volume reached 2.0 times of the rated capacity of expander, abdominal scar excision+expander removal+local expanded flap transfer repair was performed in the second stage. The skin surface area at the expansion site was measured respectively when the water injection volume reached 1.0, 1.2, 1.5, 1.8, and 2.0 times of the rated capacity of expander, and the skin expansion rate of the expansion site at corresponding multiples of expansion (1.0, 1.2, 1.5, 1.8, and 2.0 times) and adjacent multiple intervals (1.0-1.2, 1.2-1.5, 1.5-1.8, and 1.8-2.0 times) were calculated. The skin surface area of the repaired site at 0 (immediately), 1, 2, 3, 4, 5, and 6 months after operation, and the skin shrinkage rate of the repaired site at different time points (1, 2, 3, 4, 5, and 6 months after operation) and different time periods (0-1, 1-2, 2-3, 3-4, 4-5, and 5-6 months after operation) were calculated. Data were statistically analyzed with analysis of variance for repeated measurement and least significant difference-t test. Results: Compared with the expansion of 1.0 time ((287.6±2.2) cm2 and (47.0±0.7)%), the skin surface area and expansion rate of the expansion site of patients ((315.8±2.1), (356.1±2.8), (384.9±1.6), and (386.2±1.5) cm2, (51.7±0.6)%, (57.2±0.6)%, (60.4±0.6)%, and (60.5±0.6)%) were significantly increased when the expansion reached 1.2, 1.5, 1.8, and 2.0 times (with t values of 46.04, 90.38, 150.14, 159.55, 45.11, 87.83, 135.82, and 118.48, respectively, P<0.05). Compared with the expansion of 1.2 times, the skin surface area and expansion rate of the expansion site of patients were significantly increased when the expansion reached 1.5, 1.8, and 2.0 times (with t values of 49.82, 109.64, 122.14, 144.19, 49.51, and 105.85, respectively, P<0.05). Compared with the expansion of 1.5 times, the skin surface area and expansion rate of the expansion site of patients were significantly increased when the expansion reached 1.8 times (with t values of 38.93 and 39.22, respectively, P<0.05) and 2.0 times (with t values of 38.37 and 38.78, respectively, P<0.05). Compared with the expansion of 1.8 times, the skin surface area and expansion rate of the expansion site of patients both had no statistically significant differences when the expansion reached 2.0 times (with t values of 4.71 and 4.72, respectively, P>0.05). Compared with the expansion of 1.0-1.2 times, the skin expansion rate of the expansion site of patient was significantly increased when the expansion reached 1.2-1.5 times (t=6.95, P<0.05), while the skin expansion rate of the expansion site of patient was significantly decreased when the expansion reached 1.5-1.8 and 1.8-2.0 times (with t values of 5.89 and 40.75, respectively, P<0.05). Compared with the expansion of 1.2-1.5 times, the skin expansion rate of the expansion site of patient was significantly decreased when the expansion reached 1.5-1.8 and 1.8-2.0 times (with t values of 10.50 and 41.92, respectively, P<0.05). Compared with the expansion of 1.5-1.8 times, the skin expansion rate of the expansion site of patient was significantly decreased when the expansion reached 1.8-2.0 times (t=32.60, P<0.05). Compared with 0 month after operation, the skin surface area of the repaired site of patient at 1, 2, 3, 4, 5, and 6 months after operation was significantly decreased (with t values of 61.66, 82.70, 96.44, 102.81, 104.51, and 102.21, respectively, P<0.05). Compared with 1 month after operation, the skin surface area of the repaired site of patient was significantly decreased at 2, 3, 4, 5, and 6 months after operation (with t values of 37.37, 64.64, 69.40, 72.46, and 72.62, respectively, P<0.05), while the skin shrinkage rate was significantly increased (with t values of 32.29, 50.00, 52.67, 54.76, and 54.62, respectively, P<0.05). Compared with 2 months after operation, the skin surface area of the repaired site of patient was significantly decreased at 3, 4, 5, and 6 months after operation (with t values of 52.41, 60.41, 70.30, and 65.32, respectively, P<0.05), while the skin shrinkage rate was significantly increased (with t values of 52.97, 59.29, 69.68, and 64.50, respectively, P<0.05). Compared with 3 months after operation, the skin surface area of the repaired site of patient was significantly decreased at 4, 5, and 6 months after operation (with t values of 5.53, 38.00, and 38.52, respectively, P<0.05), while the skin shrinkage rate was significantly increased (with t values of 25.36, 38.59, and 37.47, respectively, P<0.05). Compared with 4 months after operation, the skin surface area (with t values of 41.10 and 50.50, respectively, P>0.05) and skin shrinkage rate (with t values of 48.09 and 50.00, respectively, P>0.05) of the repaired site of patients at 5 and 6 months after operation showed no statistically significant differences. Compared with 5 months after operation, the skin surface area and skin shrinkage rate of the repaired site of patient at 6 months after operation showed no statistically significant differences (with t values of 9.40 and 9.59, respectively, P>0.05). Compared with 0-1 month after operation, the skin shrinkage rate of the repaired site of patient at 1-2, 2-3, 3-4, 4-5, and 5-6 months after operation was significantly decreased (with t values of 13.56, 40.00, 49.21, 53.97, and 57.68, respectively, P<0.05). Compared with 1-2 months after operation, the skin shrinkage rate of the repaired site of patients at 2-3, 3-4, 4-5, and 5-6 months after operation was significantly decreased (with t values of 12.37, 27.72, 30.16, and 31.67, respectively, P<0.05). Compared with 2-3 months after operation, the skin shrinkage rate of the repaired site of patients at 3-4, 4-5, and 5-6 months after operation was significantly decreased (with t values of 33.73, 41.31, and 54.10, respectively, P<0.05). Compared with 3-4 months after operation, the skin shrinkage rate of the repaired site of patient at 4-5 and 5-6 months after operation showed no statistically significant differences (with t values of 10.90 and 23.60, respectively, P>0.05). Compared with 4-5 months after operation, the skin shrinkage rate of the repaired site of patient at 5-6 months after operation showed no statistically significant difference (t=20.90, P>0.05). Conclusions: The expander can effectively expand the abdominal skin, thus repairing the abdominal scar deformity. Maintained expansion for one month after the water injection expansion reaches 1.8 times of the rated capacity of the expander can be set as a phase Ⅱ operation node.

[Interleukin-9 promotes the activation of hepatic stellate cells in mice infected with Schistosoma japonicum].

OBJECTIVE: To investigate the effects of interleukin-9 (IL-9) in the activation of hepatic stellate cells (HSCs) in mice infected with Schistosoma japonicum. METHODS: Primary HSCs were isolated from mice 7 weeks post-infection with S. japonicum using the in situ liver perfusion and density gradient centrifugation, and cultured in vitro. HSCs were randomly assigned to the PBS control group and IL-9 stimulation group (stimulation with 20 ng/mL IL-9). HSCs were harvested 48 h and 72 h poststimulation, and the expression of α-smooth muscle actin (α-SMA), type I collagen (Col I) and type III collagen (Col III) was determined in HSCs using Western blotting. RESULTS: Following stimulation with 20 ng/mL IL-9 for 48 h, the expression of α-SMA [(0.87 ± 0.02) vs. (0.69 ± 0.01); t = 17.39, P < 0.01], Col I [(0.74 ± 0.02) vs. (0.65 ± 0.01); t = 9.56, P < 0.01] and Col III [(0.94 ±0.04) vs. (0.75 ± 0.03); t = 6.15, P < 0.01] was significantly greater in HSCs in the IL-9 stimulation group than in the PBS control group. Following stimulation with 20 ng/mL IL-9 for 72 h, the expression of α-SMA was significantly greater in HSCs in the IL-9 stimulation group than in the PBS control group[(0.76 ± 0.02) vs. (0.58 ± 0.02); t = 12.52, P < 0.01]; however, there were no significant differences between the two groups in terms of Col I [(0.68 ± 0.02) vs. (0.66 ± 0.02); t = 1.15, P > 0.05] or Col III expression [(0.75 ± 0.01) vs. (0.72 ± 0.02); t = 2.22, P > 0.05]. CONCLUSIONS: IL-9 promotes the activation of HSCs in mice infected with S. japonicum.

[PIK3CA gene mutations in Chinese women with HR+/HER2- breast cancer].

Objective: To investigate the spectrum of PIK3CA gene mutations in Chinese women with hormone receptor positive and HER2 negative (HR+/HER2-) breast cancer, to provide the genetic evidence for identifying potential beneficiaries from specific PI3K isoform inhibitors in Chinese women with breast cancer and to develop detection strategies. Methods: A total of 365 breast cancer specimens archived at the Peking Union Medical College Hospital, Beijing, China from January 2017 to October 2017 were screened. Among these patients, 186 HR+/HER2- women with invasive breast cancer were collected. PIK3CA gene mutations were detected using next generation sequencing technology. The gene variant features were then analyzed and compared with reported data. Results: Among the 186 HR+/HER2- breast cancer cases, 40 (21.5%,40/186) cases harbored PIK3CA gene mutations. Exons 9 and 20 of PIK3CA mutations occurred in 92.5%(37/40)of the tumors, which included E545K, E545G, Q546K, E542K, Q546R, P539R, E547D, H1047R, H1047L, H1047Q and N1044Y. Only one case harbored the exon 7 C420R mutation. Additionally, exons 1 (F83C) and 5 (G364R) uncommon mutations were discovered respectively in 2 cases. Based on the finding, 85.0% (34/40) of cases with known mutations could be detected using companion diagnostic methods. Moreover, 25.0% (10/40) of patients had two or three variants, which were composed of E726K/N345K, H1047Q/N345K, H1047R/G364R, H1047R/E453K, E545G/E726K, E542K/E726K, E542K/H1047R, E545K/H1047R/H1047L and E545K/E547D. The lymph node positive rate in these patients with PIK3CA mutation was remarkably higher than those without (i.e., wild type, P<0.05). Conclusions: In this group of HR+/HER2- breast cancer patients, common PIK3CA gene mutations account for the vast majority of the mutations. New rare variants in PIK3CA are also identified while their clinical significance needs to be further studied in a large cohort and/or multi-center study.

[Regional disparities in trends of global gastric cancer incidence and mortality from 1990 to 2019].

Objective: To depict gastric cancer burden trends globally and analyze geographical and socioeconomic disparities among different countries and territories. Methods: We extracted the data from Global Burden of Disease 2019 Database. We conducted the Joinpoint regression and calculated the average annual percent change (AAPC) and corresponding 95% confidence interval (CI) for age-standardized gastric cancer incidence and mortality from 1990 to 2019. Linear regression was performed to measure the association of sociodemographic index (SDI) with each country's gastric cancer incidence and mortality AAPC. We applied the age-period-cohort analysis to assess the cohort effect on gastric cancer incidence and mortality. Results: The AAPCs for gastric cancer age-standardized incidence and mortality rates from 1990 to 2019 were -1.27% (95% CI: -1.43%, -1.11%) and -1.87% (95% CI: -2.01%, -1.72%), respectively. SDI levels were negatively associated with AAPCs, which means that countries with higher SDI had higher AAPC (P<0.001). The decrease of gastric cancer burden in countries with low or medium SDI levels was slower than that globally. The age-period-cohort analysis indicated that countries with higher SDI levels had more apparent decline in birth cohort effects from 1900 to 1999. Conclusions: Countries with different socioeconomic levels have various decreasing rates for gastric cancer incidence and deaths. Countries with higher SDI levels have higher declining rates for gastric cancer burden.

[Clinical effects of free hallux-nail flap combined with the second toe composite tissue flap in the reconstruction of damaged thumb after electrical burns].

Objective: To explore the clinical effects of free hallux-nail flap combined with the second toe composite tissue flap in the reconstruction of damaged thumb after electrical burns. Methods: A retrospective observational study was conducted. From May 2018 to April 2021, 12 male patients with thumb destructive defects caused by electrical burns who met the inclusion criteria were admitted to Zhengzhou First People's Hospital, aged 27 to 58 years, including 10 cases with degree Ⅲ thumb defect and 2 cases with degree Ⅳ thumb defect after thorough debridement. The thumb was reconstructed with free hallux-nail flap combined with composite tissue flap of the second phalangeal bone, joint, and tendon with skin island. The donor site of hallux-nail flap was covered with artificial dermis in the first stage and performed with continuous vacuum sealing drainage, and covered with medium-thickness skin graft from the groin site in the second stage. The donor site in the second toe was filled and fixed with iliac bone strips. The survival of reconstructed thumb was observed 1 week after the reconstruction surgery, the survival of skin graft in the donor site of hallux-nail flap was observed 2 weeks after skin grafting, and the callus formation of the reconstructed thumb phalanx and the second toe of the donor foot was observed by X-ray 6 weeks after the reconstruction surgery. During the follow-up, the shape of reconstructed thumb was observed and the sensory function was evaluated; the function of reconstructed thumb was evaluated with trial standard for the evaluation of the functions of the upper limbs of the Hand Surgery Society of the Chinese Medical Association; whether the interphalangeal joints of the hallux and the second toe were stiff, the scar hyperplasia of the foot donor site, and whether the walking and standing functions of the donor feet were limited were observed. Results: One week after the reconstruction surgery, all the reconstructed thumbs of the patients survived. Two weeks after skin grafting, the skin grafts in the donor site of hallux-nail flap of 11 patients survived, while the skin graft in the donor site of hallux-nail flap of 1 patient was partially necrotic, which was healed completely after 10 days' dressing change. Six weeks after the reconstruction surgery, callus formation was observed in the reconstructed thumb and the second toe of the donor foot of 10 patients, the Kirschner wires were removed; while callus formation of the reconstructed thumb was poor in 2 patients, and the Kirschner wires were removed after 2 weeks of delay. During the follow-up of 6 to 24 months, the shape of reconstructed thumb was similar to that of the healthy thumb, the discrimination distance between the two points of the reconstructed thumb was 7 to 11 mm, and the functional evaluation results were excellent in 4 cases, good in 6 cases, and fair in 2 cases. The interphalangeal joints of the hallux and the second toe of the donor foot were stiff, mild scar hyperplasia was left in the donor site of foot, and the standing and walking functions of the donor foot were not significantly limited. Conclusions: The application of free hallux-nail flap combined with the second toe composite tissue flap in the reconstruction of damaged thumb after electrical burns adopts the concept of reconstruction instead of repair to close the wound. It can restore the shape and function of the damaged thumb without causing great damage to the donor foot.

[Exploration on teaching reform of cancer epidemiology course].

This study aims to explore optimized teaching mode of cancer epidemiology for undergraduates, and provide scientific ideas and basis for improving teaching quality. Non-randomized concurrent control study was used. Undergraduates, enrolled in 2018, from the department of preventive medicine in A and B medical universities were selected as research objects. Traditional teaching mode was used for cancer epidemiology course in A medical university, and innovative teaching mode named "one core, four dimensions" was adopted in B medical university. After the course, questionnaire method was used to investigate self-cognition of students, teaching satisfaction and class preparation time of teachers in B Medical University. The post-class test method was used to compare the students' grades of cancer epidemiology in the two universities. The results indicated that among the 58 students of B medical university, 94.83% (55/58) students were familiar with common types of epidemiological studies and 86.21% (50/58) mastered the evaluation indicators of screening research. Among the nine teaching faculties from B medical university, seven reported that the new teaching plan helped students to learn frontier knowledge of cancer epidemiology, and eight reported the new teaching model was conducive to the interaction between teachers and students. The text score of students in B medical university was 50.34±4.90, significantly higher than that in A medical university (46.21±4.91, t=5.20, P<0.001). The optimized teaching mode of cancer epidemiology is highly praised by students and teachers, which has the potential to improve students' grasp of cancer epidemiology, the ability to combine theory with practice, and the teaching effect of cancer epidemiology.

[Application of near infrared fluorescence imaging in detection of residual cancer in oral squamous cell carcinoma].

Objective: Local recurrence is the main cause of treatment failure in patients with oral squamous cell carcinoma (OSCC). This study was proposed to investigate the feasibility of near infrared fluorescence (NIF) via indocyanine green (ICG) for monitoring surgical marginal in operation for OSCC patients. Methods: In 35 patients with OSCC treated surgically in the Department of Oral and Maxillofacial Surgery, Nanjing University School of Medicine, from January 2019 to June 2020, ICG (0.75 mg/kg) was administered intravenously via elbow vein at (12±1) hours before surgery, and NIF was performed intraoperatively on the surgical field and the cut edge of the surgically excised specimen, and fluorescence intensity was measured for OSCC tissue and normal oral mucosa, abnormal fluorescence signals were taken and subjected to rapid cryopathological examination. Correlation between NIF tumor boundary grading and pathological tumor boundary grading was analyzed by Spearman correlation analysis. Results: Clear ICG NIF was obtained for tumor lesions in all 35 patients, with a positive rate of 100%. The fluorescence intensity of OSCC tissue was (412.73±146.56) au, which was higher than that of normal oral mucosa tissue [(279.38±82.56) au, P<0.01]. Abnormal fluorescence signals were detected at the tumor bed and the cut edge of the surgical resection specimen in 4 patients, of which 2 cases were pathologically confirmed as cancer cell residue and 2 cases as inflammatory cell infiltration. The rate of positive detection of cut margins using ICG NIF technique in OSCC was 5.7% (2/35). Twenty of the 35 OSCC patients had grade 1, 11 of grade 2, and 4 of grade 3 tumor borders revealed by NIF of surgical resection specimens, which was positively correlated with pathological tumor border (r=0.809, P<0.001). Conclusions: ICG NIF technique can effectively detect the residual cancer cells at the incision margin, which is of great clinical value in reducing local recurrence of OSCC after surgery due to intraoperative cancer residue.

[Effects of expanded frontal-parietal pedicled flap in reconstructing cervical scar contracture deformity in children after burns].

Objective: To explore the effects of expanded frontal-parietal pedicled flap in reconstructing cervical scar contracture deformity in children after burns. Methods: A retrospective observational study was conducted. From January 2015 to December 2020, 18 male children with cervical scar contracture deformity after burns who met the inclusion criteria were admitted to Zhengzhou First People's Hospital, aged 4 to 12 years, including 10 cases with degree Ⅱ cervical scar contracture deformity and 8 cases with degree Ⅲ scar contracture deformity, and were all reconstructed with expanded frontal-parietal pedicled flap. The surgery was performed in 3 stages. In the first stage, a cylindrical skin and soft tissue expander (hereinafter referred to as expander) with rated capacity of 300 to 500 mL was placed in the frontal-parietal region. The expansion time was 4 to 6 months with the total normal saline injection volume being 2.1 to 3.0 times of the rated capacity of expander. In the second stage, expander removal, scar excision, contracture release, and flap transfer were performed, with the flap areas of 18 cm×9 cm to 23 cm×13 cm and the secondary wound areas of 16 cm×8 cm to 21 cm×11 cm after scar excision and contracture release. After 3 to 4 weeks, in the third stage, the flap pedicle was cut off and restored. The rated volume of placed expander, total normal saline injection volume, type of vascular pedicle of flap, survival of flap and reconstruction of scar after the second stage surgery were recorded. The neck range of motion and cervico-mental angle were measured before surgery and one-year after surgery. The appearance of neck, occurrence of common complications in the donor and recipient sites of children, and satisfaction of children's families for treatment effects were followed up. Data were statistically analyzed with paired sample t test. Results: All the patients successfully completed the three stages of operation. The rated volume of implanted expander was 300 mL in 6 children, 400 mL in 9 children, and 500 mL in 3 children, with the volume of normal saline injection being 630 to 1 500 mL. The type of vascular pedicle of flap was double pedicle in 13 cases and was single pedicle in 5 cases. All the flaps in 17 children survived well, and the secondary wounds after neck scar excision and contracture release were all reconstructed in one procedure. In one case, the distal blood supply of the single pedicled flap was poor after the second stage surgery, with necrosis of about 2.5 cm in length. The distal necrotic tissue was removed on 10 days after the operation, and the wound was completely closed after the flap was repositioned. In the follow-up of 6 months to 3 years post operation, the cervical scar contracture deformity in 18 children was corrected without recurrence. The flap was not bloated, the texture was soft, and the appearances of chin and neck were good. The range of motion of cervical pre-buckling, extension, left flexion, and right flexion, and cervico-mental angle in one year after operation were improved compared with those before operation (with t values of 43.10, 22.64, 27.96, 20.59, and 88.42, respectively, P<0.01). The incision in the frontal donor site was located in the hairline, the scar was slight and concealed. No complication such as cranial depression was observed in expander placement site, and the children's families were satisfied with the result of reconstruction. Conclusions: Application of expanded frontal-parietal pedicled flap in reconstructing the cervical scar contracture deformity in children after burns can obviously improve the appearance and function of neck, with unlikely recurrence of postoperative scar contractures, thus it is an ideal method of reconstruction.