PVP with or without microwave ablation for the treatment of painful spinal metastases from NSCLC: a retrospective case-control study.

OBJECTIVE: To compare the clinical efficacy of percutaneous vertebroplasty (PVP) alone and microwave ablation (MWA) combined with PVP for the treatment of painful spinal metastases from non-small cell lung cancer (NSCLC). METHODS: From October 2014 to October 2021, the data of 58 NSCLC patients with refractory painful spinal metastases (visual analog scale score ≥ 5) were retrospectively collected and analyzed. Patients in Group A (n = 30) and Group B (n = 28) received PVP alone and MWA combined with PVP, respectively. The primary endpoint was pain relief. The secondary endpoints were quality of life (QoL), local tumor progression (LTP), and complications. RESULTS: The technical success rate was 100% in both groups. Patients in both groups showed similar pain relief at 1-12 weeks, but patients in Group B still showed sustained pain relief at 24 weeks compared to those in Group A (p = 0.03). The assessment of QoL showed similar changes. LTP (33.00% vs. 7.14%, p = 0.02) and cement leakage rates (40.00% vs. 7.14%, p = 0.03) were lower in Group B. The multivariate analysis demonstrated spinal metastases with a maximum diameter ≤ 3.0 cm (p = 0.027) and MWA combined with PVP (p = 0.028) were two independent protective factors for LTP. For cement leakage, spinal metastases with vertebral body compression (p = 0.019) was an independent risk factor, while MWA combined with PVP (p = 0.042) was an independent protective factor. CONCLUSION: MWA combined with PVP for painful spinal metastases from NSCLC performed more sustained pain relief (>6 months) and ultimately improved QoL with lower LTP and cement leakage rates, compared to PVP alone.

Liposome quercetin enhances the ablation effects of microwave ablation in treating the rabbit VX2 liver tumor model.

OBJECTIVE: This study aimed to investigate whether liposomal quercetin (LQ) could enhance the effects of microwave ablation (MVA) in treating the rabbit VX2 liver tumor model. METHODS: Rabbits with VX2 liver tumors were randomly divided into three groups: intravenous LQ group (LQ group), MWA group and LQ combined with MWA (LQ + MWA) group. Five rabbits were randomly selected and sacrificed from each group at 12 h and on days 3, 7 and 14 of the operation. The tumor samples were detected and quantified by immunohistochemistry, Western blot, and reverse transcription polymerase chain reaction (RT-PCR). RESULTS: For up to 7 days, the coagulation necrosis volume (CV) of the LQ + MWA group was larger than that of MWA and LQ groups (p < 0.05). Fourteen days after the operation, the total tumor volume of the LQ + MWA group was smaller than that of the LQ group and the MWA group (p < 0.05). The survival time of the LQ + MWA group was significantly longer than that of the MWA and LQ groups (p < 0.01). Heat shock protein 70 (HSP70), hypoxia inducible factor-1 α (HIF-1 α), vascular endothelial growth factor (VEGF), tumor microvessel density (MVD) were lower in the LQ + MWA group than the MWA and LQ groups at 12 h, on days 3 and 7. At hour 12 and on days 3 and 7, HSP70 mRNA and HIF-1α mRNA expression of MWA group were significantly higher than that of the LQ and LQ + MWA groups (p < 0.001). At 12 h, and on days 3 and 7, apoptotic rate of tumor cells in LQ + MWA group was higher than that of the MWA and LQ groups (p < 0.05). At 12 h and on days 3, 7 and 14, the proliferation index of tumor cells in residual tumor in LQ + MWA group was lower than that in the MWA and LQ groups (p < 0.05). CONCLUSION: Preoperative infusion of LQ can significantly enhance the MWA effects of liver VX2 tumor, inhibit the excessive proliferation of residual tumor and angiogenesis, and decrease metastasis and prolong the survival period of experimental animals.

Application of Y-shaped, coated self-expandable metallic stents for anastomotic stenosis after gastrojejunostomy (Billroth II).

BACKGROUND: Anastomotic stenosis is an infrequent but life-threatening complication after gastrojejunostomy (Billroth II). Tubular or single tubular stents have limited efficacy due to the particular anatomy. PURPOSE: To assess the feasibility of a Y-shaped, fully-coated, self-expandable, metallic stent (SEMS) for anastomotic stenosis after gastrojejunostomy (Billroth II). MATERIAL AND METHODS: Between January 2008 and August 2014, 14 patients (10 with gastric carcinoma and four with duodenal ulcers) had anastomotic stenoses following Billroth II reconstructions. Eight patients with gastric cancer had tumor recurrence near the anastomosis; two had benign strictures. The four duodenal ulcer patients had benign stenoses. An integrated Y-shaped, fully coated SEMS was designed to accord with the anatomy of residual gastrojejunal anastomotic strictures. Fourteen stents were inserted under fluoroscopic control. Follow-up was at 1, 3, 9, and 12 months, and then annually. RESULTS: All 14 stents were inserted successfully at the first attempt with a technical success rate of 100%. After stenting, abdominal symptoms resolved in all patients. All patients were followed up for 4-27 months (mean, 13.9 months). One of the eight recurrent cases died of multiple tumor metastases and liver failure after 7 months, without obstruction symptoms. In all six patients with benign anastomotic stenosis, the stents were removed successfully without complication and with no evidence of restenosis based on clinical evaluation and imaging. CONCLUSION: A Y-shaped, fully-coated SEMS proved to be a feasible and minimally invasive procedure for treating anastomotic stenosis after gastrojejunostomy (Billroth II).

Graphene oxide-loaded rapamycin coating on airway stents inhibits stent-related granulation tissue hyperplasia.

OBJECTIVES: Our objective was to explore the safety and efficacy of a graphene oxide-loaded rapamycin-coated self-expandable metallic airway stent (GO@RAPA-SEMS) in a rabbit model. METHODS: The dip coating method was used to develop a GO@RAPA-SEMS and a poly(lactic-co-glycolic)-acid loaded rapamycin-coated self-expandable metallic airway stent (PLGA@RAPA-SEMS). The surface structure was evaluated using a scanning electronic microscope. The in vitro drug-release profiles of the 2 stents were explored and compared. In the animal study, a total of 45 rabbits were randomly divided into 3 groups and underwent 3 kinds of stent placements. Computed tomography was performed to evaluate the degree of stenosis at 1, 2 and 3 months after the stent operation. Five rabbits in each group were sacrificed after the computed tomography scan. The stented trachea and blood were collected for further pathological analysis and laboratory testing. RESULTS: The in vitro drug-release study revealed that GO@RAPA-SEMS exhibited a sudden release on the first day and maintained a certain release rate on the 14th day. The PLGA@RAPA-SEMS exhibited a longer sustained release time. All 45 rabbits underwent successful stent placement. Pathological results indicated that the granulation tissue thickness in the GO@RAPA-SEMS group was less than that in the PLGA@RAPA-SEMS group. The TUNEL and hypoxia-inducible factor-1α staining results support the fact that the granulation inhibition effect in the GO@RAPA-SEMS group was greater than that in the PLGA@RAPA-SEMS group. CONCLUSIONS: GO@RAPA-SEMS effectively inhibited stent-related granulation tissue hyperplasia.

Right bronchopleural fistula treated with a novel, Y-shaped, single-plugged, covered, metallic airway stent.

BACKGROUND: Bronchopleural fistula (BPF) is an infrequent but life-threatening complication after pneumonectomy. The incidence of BPF reported in the literature varies from 0.3% to 20%. PURPOSE: To determine the feasibility and efficacy of using Y-shaped, single-plugged, covered, metallic stents to treat right bronchopleural fistulas. MATERIAL AND METHODS: We have designed a Y-shaped, single-plugged, covered, self-expandable, metallic airway stent to fit the specific anatomy of the right main bronchus. The stent has a main tube and two branches, resembling an inverted "Y". One of the branches is closed (plugged) and bullet-shaped; the other one tubular and open. The entire stent is encased in a nitinol wire mesh. Stent size can be individualized using multislice spiral computed tomography (MSCT) measurements of the airways. Under fluoroscopic guidance, we have implanted 15 Y-shaped stents in 15 patients with right bronchopleural fistulas. RESULTS: Stent insertion was successful in all patients. All fistulas were successfully closed immediately after stent placement. Follow-up was performed for 1-34 months. Positive clinical outcomes were seen in 13 of 15 patients. Two patients died of intractable pulmonary infection and multiorgan failure. The fistula completely healed and the stent could be removed in five patients; however, two of them were left with a small, aseptic, residual right lung cavity. The remaining eight patients are still alive with the stent in situ. CONCLUSION: The placement of Y-shaped, single-plugged, covered, self-expandable metallic airway stents seems to be a feasible and safe method for the treatment of bronchopleural fistulas involving the right main bronchus. This stent is a promising therapeutic alternative for bronchopleural fistulas involving the right main bronchus.

All-in-one bioactive properties of photothermal nanofibers for accelerating diabetic wound healing.

Diabetic wound healing has attracted widespread attention in biomedical engineering. However, the harsh hypoxic microenvironment (HME) comprising high glucose levels, local bleeding, and bacterial infection often leads to the formation of hyperplastic scars, increasing the clinical demand for wound dressings. Here, we report a comprehensive strategy using near-infrared NIR-assisted oxygen delivery combined with the bioactive nature of biopolymers for remodeling the HME. Black phosphorus (BP) nanosheets and hemoglobin (Hb) were self-assembled layerwise onto electrospun poly-l-lactide (PLLA) nanofibers using charged quaternized chitosan (QCS) and hyaluronic acid. BP converts NIR radiation into heat and stimulates Hb to release oxygen in situ. QCS is a hemostatic and broad-spectrum antibacterial material. Moderate BP-derived photothermal therapy can increase the sensitivity of bacteria to QCS. A series of composite wound dressings (coded as PQBH-n) with different numbers of layers were fabricated, and the in vivo diabetic wound healing potentials were tested. The molecular mechanism can be partly attributed to the cytokine-cytokine receptor interaction. Notably, this comprehensive strategy based on NIR-assisted oxygen delivery combined with the bioactive properties of biopolymers is not only applicable for fabricating multifunctional wound dressings but also has a great potential in expanding biomedical engineering fields.

Antibacterial and antihyperplasia polylactic acid/silver nanoparticles nanofiber membrane-coated airway stent for tracheal stenosis.

Antibacterial and antihyperplasia airway stents are highly desirable for tracheal stenosis. Herein, a series of polylactic acid (PLA) and silver nanoparticles (AgNPs) nanofiber membranes (PLA, PLA-4 %AgNPs and PLA-6 % AgNPs) were prepared by electrospinning. The physicochemical and biological properties of the resultant nanofiber membranes were examined. The SEM and drug release results indicated that the AgNPs were successfully introduced into PLA, and could be sustained to be released from membranes. The membranes showed antibacterial activity against S. aureus and P. aeruginosa, and cytocompatibility towards CCC-HPF-1 and NHBE cells. Furthermore, the membranes were used to cover a self-expandable metallic stent for use in the treatment of rabbit tracheal stenosis. The in vivo results revealed that the membranes, especially the AgNPs-coated airway stent could suppress tracheal stenosis by reducing inflammation and collagen deposition. Additionally, the study further confirmed that the inhibition of bacterial content in the trachea could be positively correlated with the reduction in tracheal granulation tissue hyperplasia. Conclusively, the PLA/AgNPs nanofiber membrane-coated airway stent has practical value for patients with clinical tracheal stenosis.

Comparison of three kinds of self-expandable metallic stents induced granulation tissue hyperplasia in the rabbit trachea.

To compare stent-induced granulation tissue hyperplasia of bare (SEMS), polyurethane-covered (PU-SEMS) and electrospun nanofibre-covered (EN-SEMS) self-expandable metallic stents in the rabbit trachea. Twenty-seven rabbits were randomly assigned to 3 groups that received SEMS, PU-SEMS or EN-SEMS. Computed tomography and sacrifice were performed as scheduled. Haematoxylin-eosin and Masson's trichrome staining protocols were performed for pathological analysis. The data for tracheal ventilation area ratio, qualitative histological scoring, number of epithelial layers, and thicknesses of papillary projection and submucosa were documented and statistically analysed. All stents were successfully placed under the guidance of fluoroscopy without complications. Post-stenting 3 and 7 days, computed tomography revealed that the fully expandable EN-SEMS was similar to the SEMS and PU-SEMS. The mean stented tissue score in the SEMS group was higher than those of both the PU-SEMS and EN-SEMS groups at 3 days post-stenting. The pathological findings suggested that there was no papillary projection formation 3 days after stent placement. The thickness of papillary projection in the SEMS group was significantly higher than those of the PU-SEMS and EN-SEMS groups at 7 days post-stenting. After stenting 4 weeks, the tracheal ventilation area ratio of SEMS, PU-SEMS and EN-SEMS was 0.214 ± 0.021, 0.453 ± 0.028 and 0.619 ± 0.033, respectively. There were significant between-group differences. In conclusion, the stent-induced granulation tissue formation in EN-SEMS is less severe than that of PU-SEMS and SEMS. EN-SEMS has smaller radial force, and the tracheal ventilation ratio after stent placement better than that of PU-SEMS.

Arsenic trioxide-eluting electrospun nanofiber-covered self-expandable metallic stent reduces granulation tissue hyperplasia in rabbit trachea.

Stent-related granulation tissue hyperplasia is a major complication that limits the application of stents in airways. In this study, an arsenic trioxide-eluting electrospun nanofiber-covered self-expandable metallic stent (ATO-NFCS) was developed. Poly-L-lactide-caprolactone (PLCL) was selected as the drug-carrying polymer. Stents with two different ATO contents (0.4% ATO/PLCL and 1.2% ATO/PLCL) were fabricated. The in vitro release in simulated airway fluid suggested that the total ATO release time was 1 d. The growth of human embryonic pulmonary fibroblasts (CCC-HPF-1), normal human bronchial epithelial cells and airway smooth muscle cells was inhibited by ATO. When embedded in paravertebral muscle, the nanofiber membrane showed good short-term and long-term biological effects. In an animal study, placement of the ATO-NFCS in the trachea through a delivery system under fluoroscopy was feasible. The changes in liver and kidney function 1 and 7 d after ATO-NFCS placement were within the normal range. On pathological examination, the heart, liver, spleen, lungs and kidneys were normal. The effectiveness of the ATO-NFCS in reducing granulation tissue hyperplasia and collagen deposition was demonstrated in the rabbit airway (n = 18) at 4 weeks. The present study preliminarily investigated the efficacy of the ATO-NFCS in reducing granulation tissue formation in the trachea of rabbits. The results suggest that the ATO-NFCS is safe in vivo, easy to place, and effective for the suppression of granulation tissue formation.

The influence of liposomal quercetin on liver damage induced by microwave ablation.

This study aimed to observe whether liposomal quercetin (LQ) can enhance the effect of microwave ablation (MWA) on hepatic parenchyma destruction. Forty-eight rabbits were randomly divided into three groups: LQ group, MWA group and LQ + MWA group. Serum and liver samples were collected. The coagulation volume (CV) of hepatic parenchyma, histopathological changes and liver function were compared. Hepatocyte apoptosis was examined through TUNEL. The expression of heat shock protein 70 (HSP70), hypoxia-inducible factor-1α (HIF-1α) and tumor necrosis factor-α (TNF-α) were analyzed. Compared with MWA group, the CV of coagulation necrosis in liver was significantly increased in LQ + MWA group. TUNEL results showed that the hepaocyte apoptosis was higher in LQ + MWA group than MWA group on 12 h, 24 h and 3 d, respectively. HSP70 and HIF-1α expression in both MWA group and LQ + MWA group were increased at 12 and 24 hours, peaked on day3 and dropped on day7. Compared with MWA group, HSP70 and HIF-1α expression were lower in LQ + MWA group. On the contrary, TNF-α expression was decreased in MWA group and LQ + MWA group compared with LQ group. In conclusion, LQ increased hepatocyte apoptosis and MWA-induced hepatic parenchyma destruction through suppressing HSP70 and HIF-1α expression in liver surrounding ablation zone and increasing TNF-α expression.

Customized Hinged Covered Metallic Stents for the Treatment of Benign Main Bronchial Stenosis.

BACKGROUND: To address the limitations of silicone stents, we designed a hinged self-expandable covered metallic stent. The aim of this study was to evaluate the safety and efficacy of the customized stents in clinical applications. METHODS: This was a retrospective analysis. Under conscious sedation and local anesthesia, the stents were implanted or removed by interventional radiologists, with fluoroscopic guidance. RESULTS: Of 24 patients with benign main bronchial stenosis, stents were successfully placed in 21 (87.5%). The low-pressure balloon before dilation failed in 1 case (4.17%) of left main bronchial cicatricial stenosis. In 2 other cases (8.33%), stent placement was abandoned. Stents were successfully removed between 29 and 103 days after the procedure. After stent removal, the follow-up lasted for at least 12 months. Restenosis occurred only in 1 case (4.55%) owing to bronchial collapse 3 days after stent removal. Dyspnea occurred in another case (4.55%) at 2 months after retrieval; recurrence was confirmed using bronchoscopy, leading to a left pneumonectomy. CONCLUSIONS: The described procedure is safe and easy to be performed and avoids the use of intubation, bronchoscopy, and general anesthesia.

Overcoming the delivery limitation: results of an approach to implanting an integrated self-expanding Y-shaped metallic stent in the carina.

PURPOSE: To evaluate the technical success and initial clinical safety and effectiveness of the use of a Y-shaped metallic stent for complex stenoses involving the carina. MATERIALS AND METHODS: Thirty-five consecutive patients with complex tracheobronchial stenoses involving the carina were treated with an integrated self-expandable inverted Y-shaped metallic stent and delivery system. The Y-shaped metallic stents were placed in the tracheobronchial tree with fluoroscopic guidance. Technical success, clinical success, Hugh-Jones classification, and complications were assessed during follow-up. RESULTS: The delivery of the integrated self-expandable Y-shaped metallic stent in the carinal areas was technically successful and well-tolerated in all patients. Clinical success was achieved in 31 patients (89%) 1-7 days after stent placement; the procedure failed in four patients (11%). The improvement between pre- and postoperative Hugh-Jones classification grade was statistically significant (P<.001). During follow-up (mean follow-up, 192 days+/-169), all stenoses were resolved, and general physical examination of the 31 patents showed improvement with no obvious dyspnea or bleeding. Twenty-one patients were healthy without evidence of dyspnea, and the remaining 14 patients died (mean survival, 189 days+/-172) at the time of this report. The mean and median survival periods were 217 days+/-30 and 215 days+/-108, respectively. The mean and median stent patency periods were 216 days+/-30 and 215 days+/-119, respectively. CONCLUSIONS: Deployment of an integrated, self-expandable inverted Y-shaped metallic stent with the delivery system was a safe and effective procedure for the treatment of complex tracheobronchial stenoses involving the carina.