Objective:To investigate the selection of treatment methods for renal tumors in pilots as well as the clinical significance of robot-assisted surgery by summarizing the process of robot-assisted surgery in the treatment of renal cell carcinoma in a pilot.Methods:The diagnosis, robot-assisted surgery and aeromedical assessment of a pilot with renal cell carcinoma were reported, and the related literature was reviewed.Results:The patient was a 44-year-old male transporter pilot, who was diagnosed with a left renal mass in the middle-lower pole of the kidney during a routine abdominal CT scan. After detailed preoperative evaluation that ruled out the possibility of distant metastasis and other surgical contraindications, the patient underwent robot-assisted laparoscopic partial nephrectomy in August 2022. The postoperative recovery went well, and renal function remained within normal limits at follow-ups. In March 2023, the pilot was concluded as qualified for flight after aeromedical assessment.Conclusions:Robot-assisted partial nephrectomy can significantly reduce surgical trauma, lower the risk of complications, and maximally preserve renal function. It is a good approach to renal tumors in pilots who can recover quickly.

Objective:To investigate the selection of treatment methods for renal tumors in pilots as well as the clinical significance of robot-assisted surgery by summarizing the process of robot-assisted surgery in the treatment of renal cell carcinoma in a pilot.Methods:The diagnosis, robot-assisted surgery and aeromedical assessment of a pilot with renal cell carcinoma were reported, and the related literature was reviewed.Results:The patient was a 44-year-old male transporter pilot, who was diagnosed with a left renal mass in the middle-lower pole of the kidney during a routine abdominal CT scan. After detailed preoperative evaluation that ruled out the possibility of distant metastasis and other surgical contraindications, the patient underwent robot-assisted laparoscopic partial nephrectomy in August 2022. The postoperative recovery went well, and renal function remained within normal limits at follow-ups. In March 2023, the pilot was concluded as qualified for flight after aeromedical assessment.Conclusions:Robot-assisted partial nephrectomy can significantly reduce surgical trauma, lower the risk of complications, and maximally preserve renal function. It is a good approach to renal tumors in pilots who can recover quickly.

Objective:To prepare the whole bladder acellular matrix (BAM) using the self-designed perfusion decellularization system, and evaluate the feasibility of constructing the tissue engineering bladder with the adipose-derived stem cells (ADSCs).Methods:This study was conducted from October 2020 to April 2021. The self-designed perfusion decellularization system was used, and four different decellularization protocols (group A, group B, group C and group D) were formulated, according to the flow direction of the perfusate and the action time of different decellularization solutions. Among them, the urethral orifice of the bladder tissue was used as the outflow tract of the perfusion fluid in groups A and B. The top of the bladder was cut off and used as the outflow tract of the perfusion fluid in groups C and D. In groups A and C, 1% Triton X-100 was treated for 6 h, and 1% sodium dodecyl sulfate (SDS) was treated for 2 h. In groups B and D, 1% Triton X-100 was treated for 7 h, and 1% sodium dodecyl sulfate (SDS) was treated for 1 h. In addition, the tissue in the normal bladder group was directly obtained from the natural bladder tissue, which did not require perfusion, cryopreservation and thawing. The fast and efficient decellularization protocol was screened out through HE, DAPI, Masson trichrome and Alcian Blue staining and quantitative analyses to prepare the whole bladder scaffold. The prepared BAM was used as the scaffold material, and the ADSCs were used as the seeding cells to construct the tissue engineering bladder. HE and DAPI staining were used to observe the distribution of ADSCs on the BAM.Results:HE and DAPI staining showed that there was no obvious nuclear residue in the group C. Masson trichrome and Alcian Blue staining showed that the collagen structure and glycosaminoglycan were well preserved in the group C. There was no significant difference in bladder wall thickness between the group C and the normal bladder group [(975.44±158.62)μm vs.(1 064.49±168.52)μm, P > 0.05]. The DNA content in the group C [(43.59 ±4.59) ng/mg] was lower than that in the normal bladder group, group A, group B and group D [(532.50±26.69), (135.17±6.99), (182.49±13.69) and(84.00±4.38)ng/mg], and the difference was statistically significant ( P<0.05). The collagen content [(10.98 ± 0.29)μg/mg] and glycosaminoglycan content [(2.30±0.18)μg/mg] in group C were not significantly different with those in the normal bladder group [(11.69±0.49) and (2.36±0.09)μg/mg, P>0.05]. Scanning electron microscopy showed that a large number of pore structures could be observed on the surface of the prepared BAM in groups A-D and were facilitated to cell adhesion. The isolated and cultured ADSCs were identified by flow cytometry to confirm the positive expression of CD90 and CD29, and the negative expression of CD45 and CD106. Live/dead staining and CCK-8 detection confirmed that the prepared BAM in the group C had no cytotoxicity. HE and DAPI staining showed that a large number of ADSCs were distributed on the surface and inside of the tissue engineering bladder. Conclusions:The whole bladder shape BAM prepared by the self-designed perfusion decellularization system could be used as the scaffold material for bladder tissue engineering, and the constructed tissue engineering bladder could be used for bladder repair and reconstruction.

Objective:This study aimed to investigate the physical properties, biocompatibility, and 3D printing performance of a novel hybrid bioink composed of gelatin methacrylated (GelMA) and chitin nanocrystal (ChiNC).Methods:The study was conducted from May 2021 to December 2022, four different bioinks were prepared by adding varying amounts of ChiNC to GelMA bioink. The GelMA concentration in all four bioinks was 100 mg/ml, while the ChiNC concentrations were 0 mg/ml (no ChiNC added), 5 mg/ml, 10 mg/ml, and 20 mg/ml, respectively, named as GC0, GC5, GC10, and GC20 bioinks. The cross-sectional morphology of the hydrogels formed after photocuring the four bioinks was observed using scanning electron microscopy, and the porosity was calculated. Weighing the hydrogels before and after swelling, and then calculate the equilibrium swelling rate. HUVECs were seeded on the surfaces of the hydrogels prepared from the four bioinks and cultured in medium. Cell proliferation was assessed using CCK-8 assays at 1d, 3d, and 7d to compare the proliferation rates of cells on the four hydrogels. HUVECs were added to the four bioinks, and grid-like scaffolds were printed and cultured in medium. Live-Dead staining was performed at 1d and 7d to observe cell viability. Compare the printing effect of bioinks by observing its forming continuous threads properties during extrusion. Finally, tissue-engineered bladder patches simulating the mucosal layer, submucosal layer, and muscular layer anatomical structures of the bladder wall were 3D bioprinted using the optimized bioink composition, and the stability and fidelity of the printed structures were observed to further validate the feasibility of printing multi-layered complex structures with the bioink.Results:Scanning electron microscopy revealed that the porosity of the GC0, GC5, GC10, and GC20 hydrogels were (51.43±6.23)%, (51.85±6.47)%, (50.55±4.59)%, and (42.49±2.20)%, respectively. The differences in porosity between the GC0 group and the other three groups were not statistically significant ( P=0.9994, P=0.9948, P=0.1200). The equilibrium swelling ratio of the other three groups [(8.81±0.41), (7.95±0.19), (7.71±0.14)] was significantly lower than that of the GC0 group (9.37 ± 0.49), and the differences were statistically significant ( P=0.0457, P<0.01, P<0.01). CCK-8 assay showed no significant difference in absorbance value between the GC10 group (0.360±0.009) and the GC0 group (0.357±0.007), GC5 group (0.350±0.012), and GC20 group (0.345±0.018) on the first day ( P=0.9332, P=0.5464, P=0.4937). However, on the third day, the absorbance value of the GC10 group (0.755±0.012) was significantly higher than that of the GC0 group (0.634±0.010), GC5 group (0.704±0.009), and GC20 group (0.653±0.015) ( P<0.01, P=0.0033, P=0.0002). On the seventh day, the absorbance value of the GC10 group (1.001±0.031) was significantly higher than that of the GC0 group (0.846±0.026), GC5 group (0.930±0.043), and GC20 group (0.841±0.024)( P=0.0012, P=0.1390, P=0.0010). The addition of human umbilical vein endothelial cells (HUVECs) into the four groups of hydrogels enabled the printing of grid-like scaffolds, and Live-Dead staining was performed on day 1 and day 7. The cell viability of HUVECs in the four groups on day 1 was (90.13±1.63)%, (90.6±2.45)%, (92.58±2.15)%, and (91.40±3.17)%, respectively. There were no statistically significant differences between the GC0 group and the other three groups ( P=0.9869, P=0.3093, P=0.8008). On day 7, the cell viability was (89.97±3.10)%, (92.18±2.21)%, (92.05±2.25)%, and (90.12±1.97)% for the four groups, respectively. There were no statistically significant differences between the GC0 group and the other three groups ( P=0.3965, P=0.4511, P=0.9995). Bioink extrusion test showed that the GC0 hydrogel could be extruded continuously and form threads at temperatures between 24℃ and 25℃, while the GC10 hydrogel could be extruded continuously and form threads at temperatures between 24℃ and 27℃. Printing tissue engineered bladder patches simulating the anatomical structure of the bladder mucosal layer, submucosal layer, and muscular layer using GC10 bioink, and the printed patches were stable, without collapse, and had high fidelity. Conclusions:Adding ChiNC to GelMA promotes cell adhesion, proliferation, and expands the printing window of GelMA bioink. The biocompatibility of the mixed bioink prepared by adding 10 mg/ml ChiNC in GelMA is good, capable of printing tissue-engineered bladder patches that mimic the anatomical structure of natural bladder walls.

For the damage and loss of tissues and organs caused by urinary system diseases, the current clinical treatment methods have limitations. Tissue engineering provides a therapeutic method that can replace or regenerate damaged tissues and organs through the research of cells, biological scaffolds and biologically related molecules. As an emerging manufacturing technology, three-dimensional (3D) bioprinting technology can accurately control the biological materials carrying cells, which further promotes the development of tissue engineering. This article reviews the research progress and application of 3D bioprinting technology in tissue engineering of kidney, ureter, bladder, and urethra. Finally, the main current challenges and future prospects are discussed.
Bioprinting ; Regeneration ; Technology ; Tissue Engineering/methods*

Objective:To investigate the effect of tissue engineered bladder patch constructed by double-layer silk scaffold and adipose-derived stem cells (ADSCs) in the repair and reconstruction of bladder.Methods:This study was conducted from May 2020 to March 2021. The silk fibroin (SF) aqueous solution was obtained from silkworm cocoons, and a double-layer silk scaffold composed of silk fibroin film and silk fibroin sponge was further prepared. The rat ADSCs were isolated, cultured, and the ADSCs surface markers (CD29, CD90, CD45, CD106) were identified by flow cytometry. The ADSCs were planted on a double-layer silk scaffold to construct a tissue-engineered bladder patch. Thirty-six male SD rats were randomly divided into three groups: tissue engineered bladder patch group (SF-ADSCs group, n=15), double-layer silk scaffold group (SF group, n=15), control group ( n=6). The tissue engineered bladder patch (SF-ADSCs group) and double-layer silk scaffold (SF group) were wrapped on the omentum to promote vascularization. The vascularization was evaluated by HE and immunofluorescence staining. The wrapped tissue engineered bladder patch and double-layer silk scaffold were used to repair the defective bladder. In the control group (six rats), the incision was closed immediately after the bladder tissue fully exposed. At 4 weeks and 12 weeks after operation, the general morphology of bladder tissue and cystography were performed to evaluate the recovery of bladder morphology. After the graft was harvested, HE and Masson's trichrome staining and immunofluorescence staining were used to observe the regeneration of bladder wall tissue. Urodynamics was used to assess the recovery of bladder function at 12 weeks after operation. Results:The flow cytometry results confirmed that the isolated cells positively expressed CD29 and CD90, and there was no significant expression of CD45 and CD106. Gross observation and scanning electron microscope confirmed that the preparation of double-layer silk scaffold not only had a pore structure that was conducive to cell planting, but also had good toughness and was facilitated to surgical suture. The number (43.50±2.66) and area (0.73±0.03)% of vascular-like structures in the SF-ADSCs group after the omentum encapsulation was significantly higher than that in the SF group [(24.50±3.51), (0.55±0.05)%], and the difference was statistically significant ( P<0.05). At 4 weeks after bladder repair, the histological staining of the grafts in the SF-ADSCs and SF groups showed a large number of degraded fragments of double-layer silk scaffold. At 12 weeks, the morphology of the graft in the SF-ADSCs group showed uniform bladder morphology, which was similar to that of normal bladder tissue. Immunofluorescence staining showed that the continuous urothelial layer, abundant smooth muscle tissue, vascular structure and regenerated neurons could be observed in the SF-ADSCs group. Urodynamic test showed that the bladder maximum volume (0.74±0.03)ml and compliance (16.68±0.44)μl/cm H 2O in the SF-ADSCs group, which were better than that in the SF group [(0.47±0.05)ml, (14.89±0.37)μl/cm H 2O], but lower than that in the control group [(1.12±0.08)ml, (19.34±0.45)μl/cm H 2O], and the difference was statistically significant ( P<0.05). Conclusions:The tissue engineered bladder patch constructed with double-layer silk scaffolds and ADSCs could promote the morphological repair of bladder tissue, the regeneration of bladder wall structure and the recovery of bladder physiological function.

Objective:To investigate the effect of ureteral decellularized matrix (UDM) coating on the differentiation of adipose stem cells.Methods:From January 2018 to October 2019, UDM was prepared by perfusion method. H&E staining, DAPI staining, and DNA quantification were used to assessment the residues of cellular component in UDM and normal ureter; Masson′s trichrome staining and collagen quantification evaluated the collagen retention in UDM and normal ureter; the distribution and content of glycosaminoglycan in UDM and normal ureter were analyzed through Alcian Blue staining and glycosaminoglycan quantification. Canine adipose mesenchymal stem cells (cADMSCs) were isolated and cultured and identified by flow cytometry. The UDM was digested by pepsin enzyme to prepare the decellularized matrix coating as the experimental group. Type Ⅰ rat tail collagen coating was used as a control group. The cADMSCs were seeded on different coatings, and the differentiation of the cADMSCs was detected by immunofluorescence staining and Western Blot.Results:H&E and DAPI staining showed that the nuclear residue was not observed in the UDM. The DNA quantification demonstrated that the DNA content in UDM [(38.87±3.40) ng/mg] was significantly lower than that in the normal ureter group [(1 694.63±169.83) ng/mg, P<0.05]. Masson′s trichrome staining and collagen quantification confirmed that the collagen content in UDM [(265.89 ± 16.40) μg/mg] was no significantly different from the normal ureter group [(288.73 ± 16.32) μg/mg, P>0.05]. Alcian Blue staining showed the distribution of glycosaminoglycan in the UDM, and glycosaminoglycan quantification suggested that the content of glycosaminoglycan in the UDM [(1.57 ± 0.19) μg/mg] was lower than that in the normal ureter group [(3.43 ± 0.12) μg/mg] ( P<0.05). Immunofluorescence staining and Western Blot confirmed that the expression of Alpha-smooth muscle Actin (α-SMA) in the experimental group (2.51 ± 0.27, 3.68 ± 0.33, 4.91 ± 0.45) was higher than that in the control group (0.97±0.09, 1.02 ± 0.10, 1.00 ± 0.11) at 3 d, 7 d, 10 d ( P<0.05). The expression of α-SMA in the experimental group increased gradually with culture time ( P<0.05). While no changing of α-SMA expression in the control group was recordered. Conclusions:The prepared UDM removed the cellular components, and retained the collagen structure and bioactive components well; the ureter decellularized matrix coating could promote the differentiation of cADMSCs to smooth muscle cells.

Objective To investigate the clinical efficacy of semi-open cancellous bone grafting for infected bone defect combined with soft tissue defect of lower limb.Methods A retrospective case control study was conducted to analyze the clinical data of 26 patients with infected bone defect combined with soft tissue defect of lower limb admitted to the Third Hospital of Hebei Medical University from March 2010 to August 2017.There were 16 males and 10 females,aged 16-65 years [(39.6 ± 12.8)years].The bone defect area before bone grafting was 1.4-6.0 cm [(3.3 ± 1.2) cm].The surface soft tissue defect of bone graft granules was 2.3 cm × 1.1 cm-8.5 cm × 5.0 cm after bone grafting.If the defect was segmental defect of more than 6 cm,the defect was firstly reduced by bone transport.When the defect was near the docking point,the bone defect was repaired by open bone grafting.If the defect was located at the metaphyseal end of the calcaneus or tibia,stage Ⅰ or stage Ⅱ open bone grafting was performed after debridement.After bone grafting,antibiotic-containing cement sheets were used to cover the wound in 14 patients (semi-open group),and vacuum sealing drainage (VSD) devices were used to cover the wound in 12 patients (VSD group).The time of granulation tissue covering bone graft granules,wound healing time,bone defect healing time,material cost and complications (wound infection and necrosis of bone graft granules) were compared between the two groups.The limb function was evaluated according to Paley score.Results All patients were followed up for 12-40 months [(19.3 ±7.2) months].In the semi-open group and VSD group,the time of granulation tissue coverage was 22.2 days (15.0-44.0) days and 20.2 days (15.0-44.0) days (P ＞ 0.05);wound healing time was 3.1 months (1.5-5.5) months and 3.1 months (1.5-6.5) months (P ＞ 0.05);bone defect healing time was (5.5 ± 2.2) months and (5.9 ± 2.4) months (P ＞ 0.05);the cost of covering wound materials was (2 056.1 ± 23.4) yuan and (5 555.3 ± 1 105.5) yuan respectively (P ＜ 0.05).No wound infection occurred in either group.Two patients in the semi-open group and one patient in the VSD group had bone graft granules surface necrosis (P ＞0.05).According to Paley's functional score,the results were excellent in 12 patients and good in two in the semiopen group,compared with excellent in 11 and good in one in the VSD group (P ＞ 0.05).Conclusion For infected bone defect combined with soft tissue defect of lower limb,semi-open bone grafting can simplify the nursing of wound,prevent wound infection,promote wound healing and fracture healing.It has similar therapeutic effect with VSD,but its treatment cost is significantly reduced.

Objective To explore the clinical effect of training assisted by a lower limb rehabilitation robot on the bladder and intestinal function of paraplegic spinal cord injury survivors. Methods Thirty-eight paraplegic patients with spinal cord injury were divided according to their admission order into an experimental group ( n=19) and a control group (n=19). Both groups were given conventional rehabilitation training, while the experimental group was additionally provided with robot-assisted lower limb training in three stages:adaptation, training and con-solidation. It lasted 30 minutes daily, 5 days per week for 12 weeks. Before and after the training, an urodynamics examination system was used to evaluate the maximum urine flow, bladder capacity, residual urine volume, bladder pressure and detrusor pressure. Colon transit time, mean rectal pressure and intestinal function were measured using the colon transit test, a mean rectal pressure test, and the Functional Independence Measure ( FIM) scale respective-ly. Results The average bladder volume, maximum urine flow rate, average urine flow rate, detrusor pressure, bladder compliance, average rectal pressure and intestinal FIM score of the robot training group after training were all significantly better than before the training, as were the average residual urine volume and colon transit time. After the training, the average bladder volume, maximum urine flow rate, average urine flow rate, detrusor pressure, bladder compliance and average rectal pressure of the robot training group were all significantly higher than those of the control group, while the average residual urine volume and colon transit time were significantly smaller. Then, 32％ of the patients in the experimental group achieved no less than 6 points for their average FIM score, significantly higher than in the control group. Conclusion Robot-assisted lower limb training combined with comprehensive rehabilitation training can effectively improve the bladder and intestinal function of paraplegic patients after a spinal cord injury.

Acupuncture Points ; Acupuncture Therapy ; Essential Tremor ; therapy ; Humans ; Male ; Young Adult