[Effect and mechanism of human adipose-derived stem cell exosomes on diabetic peripheral neuropathy]

Objective: To investigate the changes of artemin protein expression in diabetic peripheral neuropathy (DPN) and to explore the regulatory effect of human adipose-derived stem cell (ADSC) exosomes on the change of artemin protein expression. Methods: This research was a prospective observational clinical research combined with experimental research. Thirteen DPN patients (9 males and 4 females, aged 32 to 68 years) who were admitted to the First Affiliated Hospital of Air Force Medical University (hereinafter referred to as our hospital) from May 2022 to October 2023 and met the inclusion criteria were selected as DPN group, and 5 non-diabetes patients (4 males and 1 female, aged 29 to 61 years) who were admitted to our hospital in the same period of time and met the inclusion criteria were selected as control group. The toe nerve or sural nerve tissue in the abandoned tissue after debridement or amputation of patients in the two groups was collected. The pathological changes of nerve tissue were observed after hematoxylin-eosin staining; the protein expressions of S100β and artemin in nerve tissue were observed after immunofluorescence staining, and the artemin protein expression was quantified; the protein and mRNA expressions of artemin were detected by Western blotting and real-time fluorescent quantitative reverse transcription polymerase chain reaction, respectively (the sample number in DPN group and control group was 13 and 5, respectively). Twelve male C57BL/6 mice aged 3 to 5 days were collected to isolate Schwann cells, and the cells were divided into conventional culture group cultured routinely, high glucose alone group (cultured with high concentration of glucose solution only), and high glucose+exosome group (cultured with high concentration of glucose solution and extracted human ADSC exosomes). After 24 hours of culture, the cell proliferation activity was detected by cell counting kit 8 (n=6). After 48 hours of culture, the protein expression of artemin was detected by Western blotting (n=3). Results: Compared with those in control group, the neural supporting cells decreased and the inflammatory cells increased in the nerve tissue of patients in DPN group, showing typical manifestations of nerve injury. Immunofluorescence staining showed that compared with those in control group, the nuclei was more, and the protein expression of S100β was lower in nerve tissue of patients in DPN group. The protein expression of artemin in nerve tissue of patients in DPN group was 71±31, which was significantly lower than 1 729±62 in control group (t=76.92, P<0.05). Western blotting detection showed that the protein expression of artemin in nerve tissue of patients in DPN group was 0.74±0.08, which was significantly lower than 0.97±0.06 in control group (t=5.49, P<0.05). The artemin mRNA expression in nerve tissue of patients in DPN group was significantly lower than that in control group (t=7.65, P<0.05). After 24 hours of culture, compared with that in conventional culture group, the proliferation activities of Schwann cells in high glucose alone group and high glucose+exosome group were significantly decreased (P<0.05); compared with that in high glucose alone group, the proliferation activity of Schwann cells in high glucose+exosome group was significantly increased (P<0.05). After 48 hours of culture, compared with those in conventional culture group, the protein expressions of artemin of Schwann cells in high glucose alone group and high glucose+exosome group were significantly decreased (P<0.05); compared with that in high glucose alone group, the protein expression of artemin of Schwann cells in high glucose+exosome group was significantly increased (P<0.05). Conclusions: The protein expression of artemin in nerve tissue of DPN patients is lower than that in normal nerve tissue, which may be related to the reduction of proliferation activity of Schwann cells by high glucose. Human ADSC exosomes may improve the proliferation activity of Schwann cells by increasing artemin protein expression, thereby delaying the progression of DPN.

[Research advances on the role of Schwann cells in diabetic peripheral neuropathy]

Diabetic peripheral neuropathy (DPN) is one of the common chronic complications of diabetes, resulting in neuropathy of spinal nerve, cranial nerve, and vegetative nerve. Diabetic distal symmetric multiple neuropathy is the most representative lesion of DPN, including symptoms of bilateral limbs pain, numbness, and paresthesia, etc. DPN is one of the main reasons causing diabetic foot ulcer (DFU). Schwann cells (SCs) are the primary glia cells of the peripheral nervous system, which play very important role in repairing after nerve injury. As the target cells of chronic hyperglycemia, SCs' functions, including the formation of myelin sheath, the secretion of neurotrophic factors, energy supplying for the axon, and the guidance of axon regeneration, etc., are damaged under the action of high glucose. The destroyed functions of SCs can inhibit the repair of damaged nerves and accelerate the progress of DPN. Therefore, if the damage of high glucose to SCs can be effectively reduced, it will provide a new way for the treatment of DPN and DFU and reduce the morbidity of DFU. This review focuses on the function of SCs and its relationship with DPN.

[Effects of the anterolateral thigh chimeric perforator flaps in repairing complex wounds of foot and ankle]

Objective: To investigate the effects of anterolateral thigh chimeric perforator flap in repairing complex wounds of foot and ankle. Methods: A retrospective observational study was conducted. From May 2018 to June 2022, 23 patients who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University to repair complex wounds of foot and ankle with anterolateral thigh chimeric perforator flaps, including 15 males and 8 females, aged from 20 to 66 years. The wounds were all accompanied by bone exposure and defects, and were complicated with varying degrees of infection. All patients underwent debridement and continuous vacuum sealing drainage treatment for 1 week in stage Ⅰ, with the skin and soft tissue defect area after debridement being 10 cm×5 cm to 22 cm×7 cm. In stage Ⅱ, the anterolateral thigh chimeric perforator flap was used to cover the defective wound, of which the muscle flap was used to fill the deep invalid cavity of the ankle joint or cover bone and internal fixation exposures, and the skin flap was used to cover the superficial wound, with the area of the skin flap ranging from 11 cm×6 cm to 23 cm×8 cm, and the area of the muscle flap ranging from 4.0 cm×2.5 cm to 8.0 cm×5.0 cm. The survival of the flap was observed after operation. During follow-up, the color, texture, appearance, and complications of the flap were observed, the function of ankle joint and its range of dorsiflexion motion and plantar flexion motion were measured, and the scar hyperplasia and muscular hernia in donor area were observed. Results: Ecchymosis and epidermal necrosis occurred at the tip of the flap in 1 patient on 5 days after operation and healed after dressing change for 1 week; the other flaps of patients survived successfully. After 6 to 40 months of follow-up, the color, texture, and shape of flaps were good, but 1 patient was not satisfied with the shape of the flap because of flap swelling; the ankle joint movement was basically normal, the dorsiflexion motion was 15-30°, and the plantar flexion motion was 20-45°; the scar hyperplasia in the donor area of the flap was not obvious, and no muscular hernia occurred. Conclusions: The anterolateral thigh chimeric perforator flap can effectively fill the deep invalid cavity of ankle joint and cover the superficial wound at the same time, with minimal damage to the donor site. So it is an ideal flap for repairing the complex wounds of foot and ankle.

[A prospective randomized controlled study of antibiotic bone cement in the treatment of diabetic foot ulcer]

Objective: To investigate the clinical effects and related mechanism of antibiotic bone cement in treating diabetic foot ulcer (DFU). Methods: A prospective randomized controlled study was conducted. From August 2020 to August 2022, 24 patients with DFU who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University. According to the block randomization, the patients were divided into 2 groups, with 12 patients in each group. In antibiotic bone cement group, there were 7 male and 5 female patients, aged (64±8) years, with the ulcer area of (41±21) cm2. In silver sulfadiazine group, there were 8 male and 4 female patients, aged (62±8) years, with the ulcer area of (38±19) cm2. Under the condition of ensuring the patency of at least one main inferior genicular artery in each patient, the continuous vacuum sealing drainage was performed for 3-5 days after thorough debridement. Thereafter, the wounds in antibiotic bone cement group were treated with gentamicin-laden bone cement, and the wounds in silver sulfadiazine group were treated with silver sulfadiazine cream for dressing change. After 3 weeks of dressing change, the wound was covered with split-thickness skin graft from the lateral thigh on the affected side. Before debridement and after 3 weeks of dressing change, the blood flow intensities of wound tissue and normal skin tissue in foot were measured using laser Doppler flowmeter, and then, the percentage of relative blood flow intensity of wound and the change rate of blood flow intensity were calculated. After 3 weeks of dressing change, the wound margin tissue was taken, the number of CD31-positive neovascular and the vascular morphology were observed and detected by immunohistochemical staining, the morphology of blood vessels surrounded by CD31 and α-smooth muscle actin (α-SMA) double-positive cells was observed by immunofluorescence staining, the cell proliferation activity was evaluated by immunofluorescence staining (denoted as the ratio of Ki67 positive cells), and the protein expression of vascular endothelial growth factor receptor 2 (VEGFR2) was detected by Western blotting. The skin graft survival was observed 3-5 days after skin grafting, and the wound healing time was recorded. Data were statistically analyzed with independent sample t test and Fisher's exact probability test. Results: The percentages of relative blood flow intensity of wounds of patients before debridement were similar between the two groups (P>0.05). After 3 weeks of dressing change, the percentage of relative blood flow intensity of wounds and the change rate of blood flow intensity of patients in antibiotic bone cement group were (44.7±2.0)% and (129±12)%, respectively, which were significantly higher than (28.3±1.2)% and (41±8)% in silver sulfadiazine group (with t values of 24.15 and 20.97, respectively, P<0.05). After 3 weeks of dressing change, compared with those in silver sulfadiazine group, the number of CD31-positive neovascular in the wound margin tissue of patients in antibiotic bone cement group was significantly increased (t=33.81, P<0.05) with larger diameter and more regular arrangement, the vascular wall continuity surrounded by CD31 and α-SMA double-positive cells was better, and the ratio of Ki67 positive cells and protein expression of VEGFR2 were significantly increased (with t values of 40.97 and 47.38, respectively, P<0.05). On post skin grafting day 3-5, all the patients in antibiotic bone cement group and 8 patients in silver sulfadiazine group had good skin graft survival, while 4 patients in silver sulfadiazine group showed spotted/patchy skin graft necrosis, which were cured after corresponding treatment. The wound healing time of patients in antibiotic bone cement group was (47.1±2.9) d, which was significantly shorter than (58.8±2.3) d in silver sulfadiazine group (t=10.86, P<0.05). Conclusions: Compared with silver sulfadiazine, clinical application of antibiotic bone cement for treating DFU has the characteristics of accelerating wound healing and better reconstruction of local blood flow, which may be closely related to the fact that antibiotic bone cement promoted the local angiogenesis effectively in the wound through enhancing the expression of VEGFR2.

[Effects of exosomes from hepatocyte growth factor-modified human adipose mesenchymal stem cells on full-thickness skin defect in diabetic mice]

Objective: To investigate the effects and mechanism of exosomes from hepatocyte growth factor (HGF)-modified human adipose mesenchymal stem cells (ADSCs) on full-thickness skin defect wounds in diabetic mice. Methods: The experimental study method was adopted. Discarded adipose tissue of 3 healthy females (10-25 years old) who underwent abdominal surgery in the Department of Plastic Surgery of First Affiliated Hospital of Air Force Medical University from February to May 2021 was collected, and primary ADSCs were obtained by collagenase digestion method and cultured for 7 days. Cell morphology was observed by inverted phase contrast microscope. The ADSCs of third passage were transfected with HGF lentivirus and cultured for 5 days, and then the fluorescence of cells was observed by imaging system and the transfection rate was calculated. The exosomes of ADSCs of the third to sixth passages and the HGF transfected ADSCs of the third to sixth passages were extracted by density gradient centrifugation, respectively, and named, ADSC exosomes and HGF-ADSC exosomes. The microscopic morphology of exosomes was observed by transmission electron microscopy, and the positive expressions of CD9, CD63, and CD81 of exosomes were detected by flow cytometry, respectively. Twenty-four 6-week-old male Kunming mice were selected to make the diabetic models, and full-thickness skin defect wounds were made on the backs of mice. According to the random number table method, the mice were divided into phosphate buffer solution (PBS) group, HGF alone group, ADSC exosome alone group, and HGF-ADSC exosome group, with 6 mice in each group, and treated accordingly. On post injury day (PID) 3, 7, 10, and 14, the wounds were observed and the wound healing rate was calculated; the blood flow intensity of wound base was detected by Doppler flowmeter and the ratio of relative blood flow intensity on PID 10 was calculated. On PID 10, the number of Ki67 positive cells in wounds was detected by immunofluorescence method, and the number of new-vascularity of CD31 positive staining and tubular neovascularization in the wounds was detected by immunohistochemistry method; the protein expressions of protein endothelial nitric oxide synthase (eNOS), phosphatidylinositol 3-kinase (PI3K), phosphorylated PI3K (p-PI3K), protein kinase B (Akt) and phosphorylated Akt (p-Akt) in wounds were detected by Western blotting, and the ratios of p-PI3K to PI3K and p-Akt to Akt were calculated. On PID 14, the defect length and collagen regeneration of wound skin tissue were detected by hematoxylin and eosin staining and Masson staining, respectively, and the collagen volume fraction (CVF) was calculated. The number of samples is 3 in all cases. Data were statistically analyzed with repeated measurement analysis of variance, one-way analysis of variance, and Tukey test. Results: After 7 days of culture, the primary ADSCs were spindle shaped and arranged in vortex shape after dense growth. After 5 days of culture, HGF transfected ADSCs of the third passage carried green fluorescence, and the transfection rate was 85%. The ADSC exosomes and HGF-ADSC exosomes were similar in microscopic morphology, showing vesicular structures with an average particle size of 103 nm and 98 nm respectively, and both were CD9, CD63, and CD81 positive. On PID 3, the wounds of mice in the 4 groups were all red and swollen, with a small amount of exudate. On PID 7, the wounds of HGF-ADSC exosome group were gradually reduced, while the wounds of the other three groups were not significantly reduced. On PID 10, the wounds in the 4 groups were all reduced and scabbed. On PID 14, the wounds in HGF-ADSC exosome group were basically healed, while the residual wounds were found in the other three groups. On PID 3, the healing rates of wounds in the four groups were similar (P>0.05); On PID 7 and 10, the wound healing rates in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 13.11, 13.11, 11.89, 12.85, 11.28, and 7.74, respectively, all P<0.01); on PID 14, the wound healing rate in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 15.50, 11.64, and 6.36, respectively, all P<0.01). On PID 3, there was no obvious blood supply in wound base of mice in the 4 groups. On PID 7, microvessels began to form in the wound base of HGF-ADSC exosome group, while the wound base of the other three groups was only congested at the wound edge. On PID 10, microvessel formation in wound base was observed in the other 3 groups except in PBS group, which had no obvious blood supply. On PID 14, the blood flow intensity of wound base in HGF-ADSC exosome group was stronger than that in the other 3 groups, and the distribution was uniform. On PID 10, the ratio of wound base relative blood flow intensity in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 23.73, 19.32, and 9.48, respectively, all P<0.01); The numbers of Ki67-positive cells and new-vascularity of wounds in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 19.58, 18.20, 11.04, 20.68, 13.79, and 8.12, respectively, P<0.01). On PID 10, the protein expression level of eNOS of wounds in HGF-ADSC exosome group was higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 53.23, 42.54, and 26.54, respectively, all P<0.01); the ratio of p-PI3K to PI3K and the ratio of p-Akt to Akt of wounds in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 16.11, 11.78, 6.08, 65.54, 31.63, and 37.86, respectively, P<0.01). On PID 14, the length of skin tissue defect in the wounds of HGF-ADSC exosome group was shorter than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 20.51, 18.50, and 11.99, respectively, all P<0.01); the CVF of wounds in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group and ADSC exosome alone group (with q values of 31.31, 28.52, and 12.35, respectively, all P<0.01). Conclusions: Human HGF-ADSC exosomes can significantly promote wound healing in diabetic mice by increasing neovascularization in wound tissue, and the mechanism may be related to the increased expression of eNOS in wounds by activating PI3K/Akt signaling pathway.

[Clinical effects of free transplantation of expanded thoracodorsal artery perforator flaps in reconstructing cervical cicatrix contracture deformity after burns]

Objective: To explore the clinical effects of free transplantation of expanded thoracodorsal artery perforator flaps in reconstructing cervical cicatrix contracture deformity after burns. Methods: A retrospective observational study was conducted. From May 2018 to April 2021, 11 patients with cervical cicatrix contracture deformity after burns who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University, including 3 males and 8 females, aged 5 to 46 years, with a course of cervical cicatrix contracture deformity of 5 months to 8 years. The degree of cervical cicatrix contracture deformity was degree Ⅰ in one patient, degree Ⅱ in nine patients, and degree Ⅲ in one patient. In the first stage, according to the sizes of neck scars, one rectangular skin and soft tissue expander (hereinafter referred to as expander) with rated capacity of 200 to 600 mL was placed in the back. The expansion time was 4 to 12 months with the total normal saline injection volume being 3.0 to 3.5 times of the rated capacity of expander. In the second stage, free expanded thoracodorsal artery perforator flaps with areas of 10 cm×7 cm to 24 cm×13 cm were cut out to repair the wounds with areas of 9 cm×6 cm to 23 cm×12 cm which was formed after cervical cicatectomy. The main trunk of thoracodorsal artery and vein were selected for end-to-end anastomosis with facial artery and vein, and the donor sites were directly closed. The survival of flaps and healing of flap donor sites were observed on the 14th day post surgery. The appearances and cicatrix contracture deformity of the flaps, recovery of cervical function, and scar hyperplasia of donor sites were followed up. Results: On the 14th day post surgery, the flaps of ten patients survived, while ecchymosis and epidermal necrosis occurred in the center of flap of one patient and healed 2 weeks after dressing change. On the 14th day post surgery, the flap donor sites of 11 patients all healed well. During the follow-up of 6-12 months post surgery, the flaps of ten patients were similar to the skin around the recipient site in texture and color, while the flap of one patient was slightly swollen. All of the 11 patients had good recovery of cervical function and no obvious scar hyperplasia nor contracture in the flaps or at the donor sites. Conclusions: Application of expanded thoracodorsal artery perforator flaps can restore the appearance and function of the neck, and cause little damage to the donor site in reconstructing the cervical cicatrix contracture deformity after burns, which is worthy of clinical reference and application.

[Effects of exosomes from human adipose-derived mesenchymal stem cells on pulmonary vascular endothelial cells injury in septic mice and its mechanism]

Objective: To investigate the effects of exosomes from human adipose-derived mesenchymal stem cells (ADSCs) on pulmonary vascular endothelial cells (PMVECs) injury in septic mice and its mechanism. Methods: The experimental research method was adopted. The primary ADSCs were isolated and cultured from the discarded fresh adipose tissue of 3 patients (female, 10-25 years old), who were admitted to the First Affiliated Hospital of Air Force Medical University undergoing abdominal surgery, and the cell morphology was observed by inverted phase contrast microscope on the 5th day. The expressions of CD29, CD34, CD44, CD45, CD73, and CD90 of ADSCs in the third passage were detected by flow cytometry. The third to the fifth passage of ADSCs were collected, and their exosomes from the cell supernatant were obtained by differential ultracentrifugation, and the shape, particle size, and the protein expressions of CD9, CD63, tumor susceptibility gene 101 (TSG101), and β-actin of exosomes were detected, respectively, by transmission electron microscopy, nano-particle tracking analysis and Western blotting. Twenty-four adult male BALB/c mice were adopted and were divided into normal control group, caecal ligation perforation (CLP) alone group, and CLP+ADSC-exosome group with each group of 8 according to random number table (the same grouping method below) and were treated accordingly. At 24 h after operation, tumor necrosis factor (TNF-α) and interleukin 1β (IL-1β) levels of mice serum were detected by enzyme-linked immunosorbent assay, and lung tissue morphology of mice was detected by hematoxylin-eosin and myeloperoxidase staining, and the expression of 8-hydroxy-deoxyguanosine (8-OHdG) of mouse lung cells was detected by immunofluorescence method. Primary PMVECs were obtained from 1-month-old C57 mice regardless gender by tissue block method. The expression of CD31 of PMVECs was detected by immunofluorescence and flow cytometry. The third passage of PMVECs was co-cultured with ADSCs derived exosomes for 12 h, and the phagocytosis of exosomes by PMVECs was detected by PKH26 kit. The third passage of PMVECs were adopted and were divided into blank control group, macrophage supernatant alone group, and macrophage supernatant+ADSC-exosome group, with 3 wells in each group, which were treated accordingly. After 24 h, the content of reactive oxygen species in cells was detected by flow cytometry, the expression of 8-OHdG in cells was detected by immunofluorescence, and Transwell assay was used to determine the permeability of cell monolayer. The number of samples in above were all 3. Data were statistically analyzed with one-way analysis of variance and least significant difference t test. Results: The primary ADSCs were isolated and cultured to day 5, growing densely in a spindle shape with a typical swirl-like. The percentages of CD29, CD44, CD73 and CD90 positive cells of ADSCs in the third passage were all >90%, and the percentages of CD34 and CD45 positive cells were <5%. Exosomes derived from ADSCs of the third to fifth passages showed a typical double-cavity disc-like structure with an average particle size of 103 nm, and the protein expressions of CD9, CD63 and TSG101 of exosomes were positive, while the protein expression of β-actin of exosomes was negative. At 24 h after operation, compared with those in normal control group, both the levels of TNF-α and IL-1β of mice serum in CLP alone group were significantly increased (with t values of 28.76 and 29.69, respectively, P<0.01); compared with those in CLP alone group, both the content of TNF-α and IL-1β of mice serum in CLP+ADSC-exosome group was significantly decreased (with t values of 9.90 and 4.76, respectively, P<0.05 or P<0.01). At 24 h after surgery, the pulmonary tissue structure of mice in normal control group was clear and complete without inflammatory cell infiltration; compared with those in normal control group, the pulmonary tissue edema and inflammatory cell infiltration of mice in CLP alone group were more obvious; compared with those in CLP alone group, the pulmonary tissue edema and inflammatory cell infiltration of mice in CLP+ADSC-exosome group were significantly reduced. At 24 h after operation, endothelial cells in lung tissues of mice in 3 groups showed positive expression of CD31; compared with that in normal control group, the fluorescence intensity of 8-OHdG positive cells of the lung tissues of mice in CLP alone group was significantly increased, and compared with that in CLP alone group, the fluorescence intensity of 8-OHdG positive cells in the lung tissues of mice in CLP+ADSC-exosome group was significantly decreased. The PMVECs in the 3rd passage showed CD31 positive expression by immunofluorescence, and the result of flow cytometry showed that CD31 positive cells accounted for 99.5%. At 12 h after co-culture, ADSC-derived exosomes were successfully phagocytose by PMVECs and entered its cytoplasm. At 12 h after culture of the third passage of PMVECs, compared with that in blank control group, the fluorescence intensity of reactive oxygen species of PMVECs in macrophage supernatant alone group was significantly increased (t=15.73, P<0.01); compared with that in macrophage supernatant alone group, the fluorescence intensity of reactive oxygen species of PMVECs in macrophage supernatant+ADSC-exosome group was significantly decreased (t=4.72, P<0.01). At 12 h after culture of the third passage of PMVECs, and the 8-OHdG positive fluorescence intensity of PMVECs in macrophage supernatant alone group was significantly increased; and compared with that in blank control group, the 8-OHdG positive fluorescence intensity of PMVECs in macrophage+ADSC-exosome supernatant group was between blank control group and macrophage supernatant alone group. At 12 h after culture of the third passage PMVECs, compared with that in blank control group, the permeability of PMVECs monolayer in macrophage supernatant alone group was significantly increased (t=6.34, P<0.01); compared with that in macrophage supernatant alone group, the permeability of PMVECs monolayer cells in macrophage supernatant+ADSC-exosome group was significantly decreased (t=2.93, P<0.05). Conclusions: Exosomes derived from ADSCs can ameliorate oxidative damage in mouse lung tissue, decrease the level of reactive oxygen species, 8-OHdG expression, and permeability of PMVECs induced by macrophage supernatant.

Fe(III)-Doped Polyaminopyrrole Nanoparticle for Imaging-Guided Photothermal Therapy of Bladder Cancer

Clinically, the surgical treatment of bladder cancer often faces the problem of tumor recurrence, and the surgical treatment combined with postoperative chemotherapy to inhibit tumor recurrence also faces high toxicity and side effects. Therefore, the need for innovative bladder cancer treatments is urgent. For the past few years, with the development of nano science and technology, imaging-guided therapy using nanomaterials with both imaging and therapy functions has shown great advantages and can not only identify the locations of the tumors but also exhibit biodistributions of nanomaterials in the tumors, significantly improving the accuracy and efficacy of treatment. In this work, we synthesized Fe(III)-doped polyaminopyrrole nanoparticles (FePPy-NH₂ NPs). With low cytotoxicity and a blood circulation half-life of 7.59 h, high levels of FePPy-NH₂ NPs accumulated in bladder tumors, with an accumulation rate of up to 5.07%ID/g. The coordination of Fe(III) and the amino group in the structure can be used for magnetic resonance imaging (MRI), whereas absorption in the near-infrared region can be applied to photoacoustic imaging (PAI) and photothermal therapy (PTT). MRI and PAI accurately identified the location of the tumor, and based on the imaging data, laser irradiation was employed accurately. With a high photothermal conversion efficiency of 44.3%, the bladder tumor was completely resected without recurrence. Hematological analysis and histopathological analysis jointly confirmed the high level of safety of the experiment.

[Expression of microRNA-296 in rabbit hypertrophic scars and its role to human fibroblasts]

Objective: To investigate the expression of microRNA-296 (miR-296) in rabbit hypertrophic scars and its role in human fibroblasts (HFbs). Methods: The experimental method was used. Twelve healthy adult New Zealand long-eared rabbits regardless gender were randomly divided into normal control group and scar group, with 6 rabbits in each group. The rabbit ear hypertrophic scar model was created in scar group according to the literature, and the rabbits in normal control group did not receive any treatment. On 60 days after setting up the models in scar group, hematoxylin-eosin staining was performed to observe the growth and arrangement of fibroblasts (Fbs) in the ear scars and skin tissue of rabbits in the two groups. The mRNA expressions of miR-296 and transforming growth factor-β₁ (TGF-β₁) in ear scars and skin tissue of rabbits in the two groups were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction, and the correlation of mRNA between miR-296 and TGF-β₁ was performed with Pearson regression analysis. Two batches of HFbs were used and transfected respectively with corresponding sequences, with the 1st batch being divided into TGF-β₁ wild type+miR-296 negative control group and TGF-β₁ wild type+miR-296 mimic group and the 2nd batch being divided into TGF-β₁ mutant type+miR-296 negative control group and TGF-β₁ mutant type+miR-296 mimic group. At 48 h after transfection, luciferase reporter gene detection kit was used to detect the luciferase and renal luciferase expression of TGF-β₁ in the cells of each group, with their ratio being used to reflect the gene expression level. Two batches of HFbs were used, and each batch of cells were divided into miR-296 negative control group and miR-296 mimic group, being transfected with the corresponding sequences. At 0 (immediately), 12, 24, 36, and 48 h after transfecting the first batch of cells, the cell proliferation was detected by thiazolyl blue method. At 24 h after transfecting the second batch of cells, the expression of TGF-β₁ and collagen type Ⅰ was detected by Western blotting. The number of samples in cell experiments was 3. Data were statistically analyzed with analysis of variance for factorial design, independent sample t test. Results: On 60 days after setting up the models in scar group, the Fbs of rabbit ear scar tissue in scar group proliferated and arranged disorderly, while the growth and arrangement of Fbs in rabbit ear skin tissue in normal control group were normal. The mRNA expression of miR-296 of rabbit scar tissue in scar group (0.65±0.11) was significantly lower than 1.19±0.12 of rabbit ear skin tissue in normal control group (t=5.175, P<0.01). The mRNA expression of TGF-β₁ of rabbit ear scar tissue in scar group (1.47±0.06) was significantly higher than 1.10±0.03 of rabbit ear skin tissue in normal control group (t=12.410, P<0.01). Pearson regression analysis showed that there was a negative correlation between the mRNA expression of miR-296 and TGF-β₁ in the ear scars and skin tissue of 12 rabbits (F=7.278, P<0.05). At 48 h after transfection, the gene expression of TGF-β₁ of cells in TGF-β₁ wild type+miR-296 mimic group was significantly lower than that in TGF-β₁ wild type+miR-296 negative control group (t=35.190, P<0.01), while the gene expression of TGF-β₁ of cells in the two TGF-β₁ mutant type groups were close (P>0.05). The HFbs proliferation ability in miR-296 mimic group was significantly lower than that in miR-296 negative control group at 12, 24, 36, and 48 h after transfection(t=3.275, 11.980, 10.460, 17.260, P<0.05 or P<0.01). At 24 h after transfection, the protein expressions of TGF-β₁ and type Ⅰ collagen of cells in miR-296 negative control group were significantly higher than those in miR-296 mimic group (t=3.758, 29.390, P<0.05 or P<0.01). Conclusions: The miR-296 expression in rabbit hypertrophic scars is down-regulated; miR-296 can inhibit the proliferation of HFbs and the expression of type Ⅰ collagen by down regulating the expression of TGF-β₁.

[Research advances on the regulation of interleukin-17 signal transduction and the implication of interleukin-17 in sepsis]

Sepsis remains a leading cause of death in critical patients. Both excessive inflammatory response and long-term immunosuppression can lead to the death of sepsis patients. As a key pro-inflammatory cytokine, interleukin-17 (IL-17) plays an important role in the body's inflammatory response and immune system. The signal transduction of IL-17 is a key link in maintaining the body's health and participating in the onset and development of sepsis. This review mainly summarizes and discusses the regulation of IL-17 signal transduction and pathogenic and protective role of IL-17 in sepsis.

[Analysis of the clinical confusion and controversy of esophagogastric junction tumor from basic anatomy]

There are still many controversies in the surgical treatment of esophagogastric junction tumors in terms of surgical approach, cleaning range, and resection scope. The reason is the confusion about the scope of the esophagogastric junction. The previous domestic and foreign anatomy descriptions of this part are not enough to solve the current problems. Based on a large number of basic anatomy and clinical operations, this article proposes that the esophagogastric junction may be wrapped by a complete and separate esophagogastric junction membrane with independent anatomy other than infracardiac bursa. The structure of the transitional tissue, mainly from the distribution of submucosal veins, explained the relationship and significance of tissue transitional changes and clinical operations, and made a reasonable analysis of the current controversy based on the anatomical characteristics, which is worthy of further investigation.

[Effects and mechanism of eleutheroside E on the growth of human hypertrophic scar fibroblasts]

Objective: To investigate the effects and mechanism of eleutheroside E on the growth of human hypertrophic scar fibroblasts (Fbs). Methods: The experimental research method was used. The hypertrophic scar tissue was collected from 6 patients with hypertrophic scar (1 male and 5 females, aged 20 to 51 (37±8) years) admitted to General Hospital of Northern Theater Command, from October 2018 to March 2019. The third to seventh passages of human hypertrophic scar Fbs were cultured for later experiments. Cells were divided into normal saline group, 100 μmol/L eleutheroside E group, 200 μmol/L eleutheroside E group, and 400 μmol/L eleutheroside E group, and normal saline, eleutheroside E at the final molarity of 100, 200, and 400 μmol/L were added to cells in the corresponding groups. Cells were collected and divided into small interfering RNA (siRNA)-negative control alone group, siRNA-thrombospondin 1 (THBS1) alone group, siRNA-negative control+400 μmol/L eleutheroside E group, and siRNA-THBS1+400 μmol/L eleutheroside E group. Cells in siRNA-negative control alone group and siRNA-negative control+400 μmol/L eleutheroside E group were transfected with siRNA-negative control, cells in siRNA-THBS1 alone group and siRNA-THBS1+400 μmol/L eleutheroside E group were transfected with siRNA-THBS1. At 24 h after transfection, cells in siRNA-negative control alone group and siRNA-THBS1 alone group were added with normal saline, and cells in siRNA-negative control+400 μmol/L eleutheroside E group and siRNA-THBS1+400 μmol/L eleutheroside E group were added with eleutheroside E at the final molarity of 400 μmol/L. At 0 (immediately), 12, 24, 36, and 48 h after treatment, the cell proliferation activity (expressed as absorbance value) was detected by thiazolyl blue assay. Cells were divided into normal saline group, 200 μmol/L eleutheroside E group, 400 μmol/L eleutheroside E group, siRNA-negative control alone group, siRNA-THBS1 alone group, siRNA-negative control+400 μmol/L eleutheroside E group, and siRNA-THBS1+400 μmol/L eleutheroside E group. The corresponding treatments in each group were the same as before. At 24 h after treatment, the apoptosis was observed by Hoechst 33258 staining. Cells were collected and divided into normal saline group, 100 μmol/L eleutheroside E group, 200 μmol/L eleutheroside E group, 400 μmol/L eleutheroside E group, siRNA-negative control alone group, siRNA-THBS1 alone group, siRNA-negative control+400 μmol/L eleutheroside E group, and siRNA-THBS1+400 μmol/L eleutheroside E group. The corresponding treatments in each group were the same as before. At 24 h after treatment, the THBS1 protein level of cells was detected by Western blotting. The number of sample in each group was all 3 at each time point. Data were statistically analyzed with analysis of variance for factorial design, one-way analysis of variance, independent sample t test, and Bonferroni correction. Results: At 0 h after treatment, the absorbance values of cells in normal saline group, 100 μmol/L eleutheroside E group, 200 μmol/L eleutheroside E group, and 400 μmol/L eleutheroside E group were similar (P>0.05). At 12, 24, 36, and 48 h after treatment, the absorbance values of cells in 100 μmol/L eleutheroside E group, 200 μmol/L eleutheroside E group, and 400 μmol/L eleutheroside E group were significantly lower than those of normal saline group (t=7.64, 28.94, 13.69, 5.87, 6.96, 22.83, 14.75, 11.52, 21.09, 20.15, 29.52, 23.12, P<0.05 or P<0.01). At 0 h after treatment, the absorbance values of cells in siRNA-negative control alone group, siRNA-THBS1 alone group, siRNA-negative control+400 μmol/L eleutheroside E group, and siRNA-THBS1+400 μmol/L eleutheroside E group were similar (P>0.05). At 12, 24, 36, and 48 h after treatment, the absorbance values of cells in siRNA-THBS1 alone group and siRNA-negative control+400 μmol/L eleutheroside E group were significantly lower than those in siRNA-negative control alone group (t=7.14, 44.87, 20.67, 40.98, 9.26, 11.08, 15.33, 20.56, P<0.05 or P<0.01); the absorbance values of cells in siRNA-THBS1 alone group, siRNA-negative control+400 μmol/L eleutheroside E group, and siRNA-THBS1+400 μmol/L eleutheroside E group were similar (P>0.05). Compared with that in normal saline group, the numbers of apoptotic cells in 200 μmol/L eleutheroside E group and 400 μmol/L eleutheroside E group were increased at 24 h after treatment. At 24 h after treatment, compared with that in siRNA-negative control alone group, the numbers of apoptotic cells in siRNA-THBS1 alone group and siRNA-negative control+400 μmol/L eleutheroside E group were increased, while the numbers of apoptotic cells in siRNA-THBS1 alone group, siRNA-negative control+400 μmol/L eleutheroside E group, and siRNA-THBS1+400 μmol/L eleutheroside E group were similar. At 24 h after treatment, the protein levels of THBS1 of cells in 100 μmol/L eleutheroside E group, 200 μmol/L eleutheroside E group, and 400 μmol/L eleutheroside E group (0.87±0.12, 0.38±0.07, 0.20±0.09) were significantly lower than 1.83±0.17 in normal saline group (t=16.61, 16.17, 17.29, P<0.01). At 24 h after treatment, the protein levels of THBS1 of cells in siRNA-THBS1 alone group and siRNA-negative control+400 μmol/L eleutheroside E group (0.61±0.07, 0.58±0.07) were significantly lower than 1.86±0.07 in siRNA-negative control alone group (t=71.06, 83.80, P<0.01), and the protein levels of THBS1 of cells siRNA-THBS1 alone group, siRNA-negative control+400 μmol/L eleutheroside E group, and siRNA-THBS1+400 μmol/L eleutheroside E group (0.63±0.11) were similar (P>0.05). Conclusions: Eleutheroside E can inhibit the growth of human hypertrophic scar Fbs by down-regulating the expression of THBS1.

[Expression and effect of microRNA-205 in hypertrophic scar]

Objective: To investigate the expression and effect of microRNA-205 (miR-205) in hypertrophic scar. Methods: The experimental research method were applied. From October 2019 to January 2020, hypertrophic scar tissue from 6 patients with hypertrophic scar [1 male and 5 females, aged (36±7) years], and remaining normal skin tissue from 6 trauma patients [2 males and 4 females, aged (38±9) years] after flap transplantation operation were collected. The above-mentioned 12 patients were admitted to the General Hospital of Northern Theater Command and met the inclusion criteria. Real time fluorescent quantitative polymerase chain reaction was used to detect the mRNA expressions of miR-205 and thrombospondin-1 (TSP-1). The hypertrophic scar tissue was taken to culture the 3rd to 5th passage of fibroblasts (Fbs) for the follow-up experiments. Fbs of hypertrophic scar was divided into TSP-1+miR-205 control group, TSP-1+miR-205 mimic group, TSP-1 mutant+miR-205 control group, TSP-1 mutant +miR-205 mimic group, which were transfected with the corresponding sequences. At 48 h after transfection, the expressions of luciferase and renal luciferase were detected by luciferase reporter gene detection kit, and the luciferase/renal luciferase ratio was calculated to indicate the activity of TSP-1. Two batches of hypertrophic scar Fbs were collected and divided into miR-205 control group, miR-205 mimic group, and miR-205 inhibitor group and miR-205 control group, miR-205 mimic group, and miR-205 mimic+TSP-1 group, respectively, which were transfected with the corresponding sequences. At 0 (immediately), 12, 24, 36, and 48 h after transfection, the cell viability was detected by microplate reader. Two batches of hypertrophic scar Fbs were collected, grouped, and treated as the cell viability detecting experiment. At 24 h after transfection, Hoechst 33258 staining was performed to observe the nuclear shrinkage, so as to reflect the apoptosis of Fbs. The number of samples in cell experiment was 3. Data were statistically analyzed with analysis of variance for factorial design, one-way analysis of variance, and t test. Results: The mRNA expression of miR-205 in hypertrophic scar tissue was 0.54±0.05, which was significantly lower than 1.26±0.07 in normal skin tissue (t=8.213, P<0.01). The expression of TSP-1 mRNA in hypertrophic scar tissue was 1.46±0.07, which was significantly higher than 0.68±0.11 in normal skin tissue (t=6.031, P<0.01). At 48 h after transfection, the luciferase/renal luciferase ratio reflecting the TSP-1 activity of cells in TSP-1+miR-205 mimic group was 0.532±0.028, which was significantly lower than 0.998±0.012 in TSP-1+miR-205 control group (t=26.500, P<0.01), and the luciferase/renal luciferase ratio of cells in TSP-1 mutant+miR-205 mimic group was 0.963±0.012, which was close to 0.976±0.010 in TSP-1 mutant+miR-205 control group (t=0.816, P>0.05). At 12, 24, 36, and 48 h after transfection, the cell viability in miR-205 mimic group was significantly lower than that in miR-205 control group (t=6.169, 12.670, 27.130, 12.670, P<0.05 or P<0.01). At 0, 12, 24, 36, and 48 h after transfection, the cell viability in miR-205 inhibitor group was significantly higher than that in miR-205 control group (t=6.169, 7.221, 7.787, 7.835, 13.030, P<0.05 or P<0.01). At 12, 24, 36, and 48 h after transfection, the cell viability in miR-205 mimic group was significantly lower than that in miR-205 control group and miR-205 mimic+TSP-1 group (t=8.118, 26.970, 39.550, 42.490, 14.570, 12.240, 36.830, 45.220, P<0.05 or P<0.01). At 24 h after transfection, compared with miR-205 control group, the cell apoptosis in miR-205 mimic group was increased, and the cell apoptosis in miR-205 inhibitor group was decreased. At 24 h after transfection, compared with miR-205 mimic group, the cell apoptosis in miR-205 control group miR-205 mimic+TSP-1 group were decreased. Conclusions: miR-205 can inhibit the proliferation and promote the apoptosis of Fbs in hypertrophic scar by inhibiting the expression of TSP-1, which has the potential to be the therapeutic target for hypertrophic scar.

[Clinical effects of combined application of skin-stretching device and vacuum sealing drainage in repairing the diabetic foot wounds]

Objective: To investigate the clinical effects of skin-stretching device (hereinafter referred to as stretcher) combined with vacuum sealing drainage (VSD) in repairing diabetic foot wounds. Methods: From March 2016 to January 2020, 25 patients with diabetic foot wounds were admitted to the First Affiliated Hospital of Air Force Medical University, including 18 males and 7 females, with age of 40 to 70 years. After debridement, intermittent VSD was performed for 3 to 10 days, with negative pressure value of -10.67 kPa. Then, the wound area was 5.0 cm×3.0 cm to 10.0 cm×7.0 cm. After infection control and detumescence, the wound was treated with stretcher for 3 to 5 days. The wound area after stretching ranged from 5.0 cm×0.3 cm to 10.0 cm×0.5 cm. The wound was closed with full-thickness suture. Two weeks after the suturing operation, the healing grade of the foot wound of patients was observed, and the serious complications such as recurrence of ulcer wound and gangrene on the foot, scar condition of the wound were observed during follow-up. Results: Two weeks after the suturing operation, the wounds of 23 patients were healed with grade A. Soft tissue infection ulcer relapsed in 2 patients during the stretch period. After anti-infection, thorough debridement, and VSD, the wounds were healed after another 16 days of stretch treatment. During the follow-up of 3 to 36 months, 23 patients had linear scar left on the stretch wounds, and the skin elasticity, color, sensation was similar to the surrounding normal tissue, and the limb mobility was good, and 2 patients had obvious scar hyperplasia. One patient had recurrence of diabetic foot and serious vascular occlusion and gangrene in the affected limb at follow-up of 10 months, which was treated with amputation of the lower leg. Conclusions: The use of stretcher combined with VSD in treating diabetic foot wound can avoid donor site injury, with healed wound achieving similar appearance to adjacent skin and satisfactory repair effects.

Targeted multifunctional nanomaterials with MRI, chemotherapy and photothermal therapy for the diagnosis and treatment of bladder cancer

Folate-modified vincristine-loaded polydopamine-coated Fe₃O₄ superparticles are designed as multifunctional nanomaterials for the imaging and treatment of bladder cancer.

Tumor Microenvironment-Responsive Nanoshuttles with Sodium Citrate Modification for Hierarchical Targeting and Improved Tumor Theranostics

Enhancement of permeability and the retention effect is one of the main pathways for the accumulation of nanomaterials in tumor sites, but poor cellular internalization and rapid clearance of nanomaterials always hamper the efficacy of imaging diagnosis and treatment. With the consideration of both high tumor accumulation and cellular internalization, positively charged nanomaterials can adhere to the tumor cell membrane by an electrostatic force, which is conducive to cellular internalization, but they are easily recognized and cleared during blood circulation. However, negatively charged nanomaterials show an enhanced stealth-like effect and possess a long blood circulation time, which is conducive to tumor accumulation. Therefore, in this work, on the basis of the shielding effect of citrate ions to positive charge and the protonation under an acidic tumor microenvironment, pH-sensitive sodium citrate-modified polyaniline nanoshuttles (NSs) with negative charge during blood circulation but positive charge in tumor sites are designed. With this hierarchical targeting strategy, the blood circulation half-life increases from 4.35 to 7.33 h, and the retention rate of NSs in tumors increases from 5.29 to 8.57% ID/g. Because the retention rate of NSs is increased, the magnetic resonance imaging resolution and signal intensity are significantly improved. A synergistic treatment of tumors is further achieved by means of photothermal therapy with laser irradiation and chemotherapy via heat-stimulated drug release.

[Effects of free superficial temporal fascia flaps and skin grafts in repairing deep wounds in posterior ankle region of extensively burned patients]

Objective: To observe the effects of the method of combining free superficial temporal fascia flaps with skin grafts in repairing deep wounds in posterior ankle region of extensively burned patients. Methods: From September 2013 to February 2017, 11 extensively burned patients with deep tissue defects in posterior ankle region were treated in our unit. Two patients had tissue defects in bilateral posterior ankle regions. The wound sizes ranged from 5.8 cm×4.6 cm to 11.7 cm×5.2 cm. Free superficial temporal fascia flaps with the same sizes as the wounds were designed and resected to repair wounds in posterior ankle regions after debridement. The proximal end of superficial temporal veins and posterior tibial veins were performed with end-to-end anastomosis, and superficial temporal arteries and posterior tibial arteries were performed with end-to-side anastomosis. Skin grafts were resected to cover the superficial temporal fascia flaps according to patients' condition of donor sites. The donor sites were sutured directly. Results: All fascial flaps in 11 patients survived, while 2 skin grafts had partial necrosis, and they healed after secondary skin graft. All patients were followed up for 6 to 13 months, and the shape and function of the operation sites in all patients recovered well. Conclusions: The method of combining free superficial temporal fascia flaps with skin grafts can repair deep wounds in posterior ankle regions of extensively burned patients. It has the advantages of good appearances in the recipient sites, strong resistances to infection of fascia flaps, minimal damages to the donor sites, short course of disease, and good prognosis of patients.

[Strategy for wound repair of skin and soft tissue defect and systematic rehabilitation treatment for functional reconstruction of patients with severe burn or trauma on knees]

Objective: Strategy for wound repair of skin and soft tissue defect and systematic rehabilitation treatment for functional reconstruction of patients with severe burn or trauma on knees. Methods: From January 2015 to October 2016, 26 patients with skin and soft tissue defect on knees after severe burn or trauma were hospitalized in our unit. Among these patients, 14 patients had patellar ligament defect, and 16 patients had knee joint capsule defect. Wound debridement was operated on 1 to 3 days after admission. After debridement, the area of skin and soft tissue defect ranged from 10 cm×7 cm to 42 cm×18 cm. Vacuum sealing drainage (VSD) treatment was performed after debridement, and flap transplantation operation was performed after VSD treatment for 5 to 7 days. Defects of nine patients were treated with local rotation flaps. Seven patients with skin and soft tissue defects on knees and knee joint capsule defects of 5 cm×3 cm to 9 cm×7 cm were treated with free anterolateral femoral flaps combined with fascia lata. Ten patients with skin and soft tissue defects on knees and patellar ligament defects of 6 cm×3 cm to 12 cm×4 cm were treated with free anterolateral femoral flaps combined with iliotibial tract. The area of flaps ranged from 11 cm×9 cm to 22 cm×15 cm. After flap transplantation operation, functional reconstruction of knee joint was carried out according to early, continuous, and sequential systematic rehabilitation treatment strategy. The pain degree and function of knee joint of patients were scored by the International Knee Documentation Committee (IKDC) Knee Evaluation Form before operation and 12 months after operation. The knee joint flexion and extension degrees of patients were measured by joint protractor in 2 weeks and 12 months after operation. The color Doppler ultrasound was used to evaluate integrity of knee joint capsule and continuity of patellar ligament of patients in 6 and 12 months after operation. Results: All flaps of 26 patients survived well, and wounds healed completely after the operation. Distal parts of flaps of 2 patients treated with free anterolateral femoral flaps had local necrosis after the operation, and their wounds healed after debridement and transplantation of autologous intermediate split-thickness skin graft of thigh. The IKDC Knee Evaluation Form score of patients was (79±8) points in 12 months after operation, which was significantly higher than (64±7) points before operation (t=7.20, P<0.05). The flexion degree of knee joint of patients was (117±10)° in 12 months after operation, which was significantly larger than (35±8)° in 2 weeks after operation (t=32.65, P<0.05). The extension degree of knee joint of patients was (12±9)° in 12 months after operation, which was significantly smaller than (61±9)° in 2 weeks after operation (t=19.63, P<0.05). In 6 and 12 months after operation, 9 patients treated with local rotation flaps had good integrity of knee joint capsule and continuity of patellar ligament; 7 patients treated with free anterolateral femoral flaps and fascia lata had good integrity of knee joint capsule; 10 patients treated with free anterolateral femoral flaps and iliotibial tract had good continuity of patellar ligament. During follow-up of 12 months, all flaps survived well; knees of all patients had good appearance; knee joints functioned normally. Conclusions: Good appearance and function of knees can be achieved by repairing wound of skin and soft tissue defect on knees after severe burn or trauma with local rotation flaps or free anterolateral femoral flaps with fascia lata or iliotibial tract plus systematic rehabilitation treatment of knee joint in early stage after flap transplantation operation.

Combined Kidney Transplantation and Splenic Fossa Auxiliary Heterotopic Liver Transplantation in a Highly Sensitized Recipient: A Case Report

BACKGROUND

Combined kidney and auxiliary orthotopic liver transplantation from the same donor is used to treat highly sensitized renal transplant recipients. Auxiliary liver can protect the transplanted kidney against hyperacute rejection.

METHODS

In the current case, combined kidney and splenic fossa auxiliary heterotopic liver transplantation was performed from the same donor for a highly sensitized recipient without preoperative preconditioning. No postoperative hyperacute rejection occurred.

RESULTS

Seven days after surgery, preexisting antibody levels rose and decreased after treatment; meanwhile, the function of transplanted kidney returned to normal. During 24 months of follow-up, the grafts showed good blood perfusion and functioned well. The levels of preexisting antibodies, donor-specific antibodies (DSA) and C1q-fixing human leukocyte antigen (C1q-HLA) antibodies, all decreased.

CONCLUSIONS

Combined kidney and splenic fossa auxiliary heterotopic liver transplantation can be used in renal transplantation for highly sensitized recipients.

[Lay emphasis on the basic research in the field of burn surgery in China]

The therapeutic methods and effects have been improved greatly in burn care and management with several important advancements in the past few decades, resulting in more effective patient stabilization and significantly decreased mortality in China. However, the challenging clinical problems still exist, such as a lack of ideally efficient scheme and drugs to protect damaged tissue and internal organs after severe burn, the limited functional cosmetic outcomes of current treatment techniques and synthetic skin substitutes for deep burn wound repair and reconstruction, the high mortality of severe sepsis accompanying with burn injury patients, and the uncontrolled scar formation and modification or potential regeneration in burn wound healing, a further exploration into both underling mechanisms and curable therapies. This article emphasizes the important roles of the basic study in exploration of above clinical issues in the viewpoint of the advanced development of modern life sciences and relevant techniques.

ABH-Glycan Microarray Characterizes ABO Subtype Antibodies: Fine Specificity of Immune Tolerance After ABO-Incompatible Transplantation

Organ transplantation from ABO blood group-incompatible (ABOi) donors requires accurate detection, effective removal and subsequent surveillance of antidonor antibodies. Because ABH antigen subtypes are expressed differently in various cells and organs, measurement of antibodies specific for the antigen subtypes in the graft is essential. Erythrocyte agglutination, the century-old assay used clinically, does not discriminate subtype-specific ABO antibodies and provides limited information on antibody isotypes. We designed and created an ABO-glycan microarray and demonstrated the precise assessment of both the presence and, importantly, the absence of donor-specific antibodies in an international study of pediatric heart transplant patients. Specific IgM, IgG, and IgA isotype antibodies to nonself ABH subtypes were detected in control participants and recipients of ABO-compatible transplants. Conversely, in children who received ABOi transplants, antibodies specific for A subtype II and/or B subtype II antigens-the only ABH antigen subtypes expressed in heart tissue-were absent, demonstrating the fine specificity of B cell tolerance to donor/graft blood group antigens. In contrast to the hemagglutination assay, the ABO-glycan microarray allows detailed characterization of donor-specific antibodies necessary for effective transplant management, representing a major step forward in precise ABO antibody detection.

Preparation of adriamycin magnetic albumin microspheres and their experimental antitumor effects in vitro and in vivo

The adriamycin magnetic microspheres (ADM-MAMs) were prepared by the heat-stabilized protein methods. Their physico-chemical properties were examined; their cytotoxicities against tumor cells in vitro were assayed by a modified MTT method, and their effects were observed on the implanted gastric tumor in Wistar rats given ADM-MAMs via alimentary canal at the presence of the external magnetic fields. The results showed that the ADM-MAMs were successfully prepared and had cytotoxic effect on tumor cells in vitro similar to the free ADM (P > 0.05). The inhibitory effects of ADM-MAMs on the implanted gastric tumor in vivo were significantly increased as compared with the controls (P < 0.01). Our results suggested that ADM-MAMs were a new type of adriamycin (ADM) preparation and its form alteration did not affect its anticancer effects.

Chemical Basis for Qualitative and Quantitative Differences Between ABO Blood Groups and Subgroups: Implications for Organ Transplantation

Blood group ABH(O) carbohydrate antigens are carried by precursor structures denoted type I-IV chains, creating unique antigen epitopes that may differ in expression between circulating erythrocytes and vascular endothelial cells. Characterization of such differences is invaluable in many clinical settings including transplantation. Monoclonal antibodies were generated and epitope specificities were characterized against chemically synthesized type I-IV ABH and related glycans. Antigen expression was detected on endomyocardial biopsies (n = 50) and spleen (n = 11) by immunohistochemical staining and on erythrocytes by flow cytometry. On vascular endothelial cells of heart and spleen, only type II-based ABH antigens were expressed; type III/IV structures were not detected. Type II-based ABH were expressed on erythrocytes of all blood groups. Group A1 and A2 erythrocytes additionally expressed type III/IV precursors, whereas group B and O erythrocytes did not. Intensity of A/B antigen expression differed among group A1 , A2 , A1 B, A2 B and B erythrocytes. On group A2 erythrocytes, type III H structures were largely un-glycosylated with the terminal "A" sugar α-GalNAc. Together, these studies define qualitative and quantitative differences in ABH antigen expression between erythrocytes and vascular tissues. These expression profiles have important implications that must be considered in clinical settings of ABO-incompatible transplantation when interpreting anti-ABO antibodies measured by hemagglutination assays with reagent erythrocytes.

Association of fat-mass and obesity-associated gene FTO rs9939609 polymorphism with the risk of obesity among children and adolescents: a meta-analysis

OBJECTIVE

To elucidate the association of fat-mass and obesity-associated gene (FTO) rs9939609 polymorphism with obesity among children and adolescents.

METHODS

A literature search was conducted in PubMed, MEDLINE, Springer, and Google scholar to identify eligible studies. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used for four models: co-dominant model (AA vs. TT, AT vs. TT), dominant model (AA + AT vs. TT), recessive model (AA vs. AT + TT), and allelic model (A vs. T). Subgroup analyses stratified by ethnicity (Caucasian, others) and participants (children, children and adolescents) were assessed under allelic model. The heterogeneity and publication bias were examined.

RESULTS

This meta-analysis included 12 eligible studies consisting 5,000 cases and 9,853 controls. The results revealed that FTO rs9939609 polymorphism was significantly associated with the increased risk of obesity in co-dominant model (AA vs. TT: OR = 1.91, 95% CI: 1.47-2.48, p < 0.01; AT vs. TT: OR = 1.18, 95% CI: 1.02-1.38, p = 0.03), dominant model (AA + AT vs. TT: OR = 1.47, 95% CI: 1.35-1.59, p < 0.01), recessive model (AA vs. AT + TT: OR = 1.79, 95% CI: 1.47-2.17, p < 0.01), and allelic model (A vs. T: OR = 1.39, 95% CI: 1.22-1.58, p < 0.01). Similar results were obtained for the subgroup analyses stratified by ethnicity and participants under allelic model.

CONCLUSIONS

FTO rs9939609 polymorphism is associated with the increased risk of obesity among children and adolescents, especially the homozygous carriers.

Identification of potential therapeutic targets for melanoma using gene expression analysis

Metastatic melanoma represents a significant cause of death in patients with melanoma and the frequency is increasing. The aim of this study was to identify potential therapeutic targets for metastatic melanoma. Gene expression profile GSE44660 was downloaded from Gene Expression Omnibus database. A total of 22 samples were analyzed in our study, including 3 specimens of normal melanocytes, 12 specimens of melanoma LNM (lymph node metastasis) and 7 specimens of MBM (melanoma brain metastasis). DEGs (differentially expressed genes) in LNM and MBM were identified respectively using Limma package. GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways analyses of common DEGs between two comparison groups were performed using DAVID, followed by cancer-related genes and transcription factor analysis. PPI (protein-protein interaction) network was constructed by STRING, and significant key genes were selected. Totally, 401 common DEGs were identified. Disease analysis showed that ICAM1 (intercellular adhesion molecule 1) and NBN (nibrin) were related to melanoma. In the PPI network, BIRC5 (baculoviral IAP repeat containing 5), BUB1 (BUB1 mitotic checkpoint serine/threonine kinase), GMNN (geminin, DNA replication inhibitor), AURKA (aurora kinase A), TOP2A (topoisomerase (DNA) II alpha) and BUB1B (BUB1 mitotic checkpoint serine/threonine kinase B) were with higher degree more than 50. ICAM1, NBN, BIRC5, BUB1, BUB1B, GMNN, AURKA and TOP2A may play key roles in the progression and development of melanoma. They may be used as specific therapeutic targets in the treatment of metastatic melanoma. However, further experiments are still needed to confirm our results.

Inhibition enhancer of zeste homologue 2 promotes senescence and apoptosis induced by doxorubicin in p53 mutant gastric cancer cells

OBJECTIVES

Enhancer of zeste homologue 2 (EZH2) is crucially involved in epigenetic silencing by acting as a histone methyltransferase. Although EZH2 is overexpressed in many cancers and is involved in malignant cell proliferation and invasion, the role of EZH2 in senescence induced by DNA damage has up to now remained largely unknown. In this study, we sought to explore the outcome of EZH2 depletion along with exposure of doxorubicin (DOX), and related mechanisms, in gastric cancer cells.

MATERIALS AND METHODS

Here, senescence induced by DNA damage was achieved in gastric cancer cells by DOX treatment. EZH2 was downregulated by transfection with siRNA or treated with (-)-epigallocatechin-3-gallate, a targeted inhibitor. Senescence-associated β galactosidase (SA-β-gal) and formation of senescence-associated heterochromatin foci were used to identify cell senescence. To investigate effects of EZH2 depletion on the cell cycle, apoptosis and proliferation, flow cytometry and MTT analysis were employed. Changes in p53-p21 axis activation were detected by Western blotting.

RESULTS

We found that cell proliferative arrest caused by DOX could be promoted by EZH2 depletion. Mechanistically, EZH2 depletion not only worked in coordination with DNA damage during the progression of cell senescence but also promoted apoptosis in p53 mutant cells. However, it had no cooperative relationship with DOX in p53 wild-type cells.

CONCLUSIONS

These data help unravel a crucial role for EZH2 in senescence and apoptosis in gastric cancer cells and that p53 genomic status was associated with different cell responses to EZH2 silencing.