Adenosine Encapsulation and Characterization through Layer-by-Layer Assembly of Hydroxypropyl-ß-Cyclodextrin and Whey Protein Isolate as Wall Materials.

Adenosine, as a water-soluble active substance, has various pharmacological effects. This study proposes a layer-by-layer assembly method of composite wall materials, using hydroxypropyl-ß-cyclodextrin as the inner wall and whey protein isolate as the outer wall, to encapsulate adenosine within the core material, aiming to enhance adenosine microcapsules' stability through intermolecular interactions. By combining isothermal titration calorimetry with molecular modeling analysis, it was determined that the core material and the inner wall and the inner wall and the outer wall interact through intermolecular forces. Adenosine and hydroxypropyl-ß-cyclodextrin form an optimal 1:1 complex through hydrophobic interactions, while hydroxypropyl-ß-cyclodextrin and whey protein isolate interact through hydrogen bonds. The embedding rate of AD/Hp-ß-CD/WPI microcapsules was 36.80%, and the 24 h retention rate under the release behavior test was 76.09%. The method of preparing adenosine microcapsules using composite wall materials is environmentally friendly and shows broad application prospects in storage and delivery systems with sustained release properties.

ISG15 Promotes Progression and Gemcitabine Resistance of Pancreatic Cancer Cells Through ATG7.

Chemoresistance is an obstacle of improving pancreatic cancer (PC) prognosis. However, the biological function of ISG15 in PC and whether it correlates with the resistance to chemotherapy are still unknown. Here, we aimed to reveal the clinical significance of ISG15 in PC and its regulatory mechanism in cancer progression and resistance to therapy. The level of ISG15, a protein involved in post-translational modifications, is elevated in PC tissues. Clinically, higher ISG15 expression correlates with higher PC grades, stronger resistance to treatment and poorer prognosis. Moreover, ISG15 promotes the proliferation, migration, invasion, colony formation of PC cells and resistance to Gemcitabine, a classic chemotherapeutics for PC, both in vitro and in vivo. ISG15 promotes progression and resistance to therapy in PC cells by binding to ATG7, reducing its degradation, and thereby leading to enhanced autophagy in PC cells. ISG15 may be used as both a potential diagnosis marker and sensitizer for chemotherapeutics such as Gemcitabine during PC intervention.

The prognostic value and biological functions of HFM1 in breast cancer.

Aim: HFM1 has been reported to be associated with meiosis and ovarian insufficiency, but its role in tumors remains unknown. This study aims to explore the functions and potential mechanism of HFM1 in breast cancer. Methods: Several databases, protein-protein interactions, gene ontology and the Kyoto Encyclopedia of Genes and Genomes were used for bioinformatic analysis. Tissue microarrays and cell viability assays were used to detect the expression of HFM1 and tamoxifen resistance, respectively. Results: HFM1 was downregulated in breast cancer with poor prognosis and may modulate DNA damage repair pathways and immune infiltration. Moreover, HFM1 may mediate ovarian steroidogenesis and participate in tamoxifen resistance of estrogen receptor-positive breast cancer cells. Conclusion: We presented a first study on biological functions and potential mechanisms of HFM1 in cancers.

The role and function of the protein HFM1 in tumors remains unknown. We explored the functions and potential mechanism of HFM1 in breast cancer through several known databases, clinical samples and cell experiments. We found that HFM1 was downregulated in breast cancer with a poor prognosis. HFM1 may mediate ovarian steroidogenesis and participate in tamoxifen resistance of estrogen receptor-positive breast cancer cells. Here we first put forward the relationship between HFM1 and the prognosis of breast cancer, and provided relevant clues for mechanism exploration.

Upregulation of KLHL17 promotes the proliferation and migration of non-small cell lung cancer by activating the Ras/MAPK signaling pathway.

Analysis of the Gene Expression Profiling Interactive Analysis (GEPIA) database revealed that Kelch-like 17 (KLHL17) is overexpressed in non-small cell lung cancer (NSCLC) including adenocarcinoma (ADC) and squamous cell carcinoma (SCC). We therefore explored the role of KLHL17 in the development and progression of NSCLC. Immunohistochemistry and western blotting showed that KLHL17 expression was significantly higher in the tumor tissues from 173 patients with NSCLC, compared with the corresponding non-neoplastic tissue. In addition, upregulated KLHL17 expression was positively correlated with tumor size, lymph node metastasis and tumor node metastasis (TNM) stage, and affected the overall survival (OS) of patients with NSCLC. Consistent with clinical samples, in vitro studies demonstrated that KLHL17 expression was higher in various cell lines of NSCLC (A549, H1299, H460 and SK cells) as compared to normal human bronchial epithelial cells (HBE cells). Overexpression of KLHL17 in the cell lines of NSCLC with KLHL17-Flag plasmid promoted the proliferation and migration of tumor cells, which was associated with elevated activation of Rat sarcoma/Mitogen-activated protein kinases (Ras/MAPK) signaling and increased expression of cyclin D1, cyclin D-dependent kinases 4 (CDK4), matrix metalloproteinase 2 (MMP2) and Ras homolog gene family member A (RhoA). In contrast, knockdown of KLHL17 in the cell lines of NSCLC using KLHL17 small interfering RNA suppressed the proliferation and migration of tumor cells, in association with reduced activation of Ras/MAPK signaling and decreased expression of cyclin D1, CDK4, MMP2 and RhoA. Moreover, treatment of tumor cells with Ras inhibitor salirasib prevented KLHL17-induced Ras/MAPK activity as well as tumor proliferation and migration. These results suggest that upregulated KLHL17 in NSCLC promotes the proliferation and migration of tumor by activating Ras/MAPK signaling pathway. Therefore, KLHL17 may be a novel therapeutic target for the treatment of NSCLC.

A comprehensive bioinformatic analysis of RanBP9 expression and its relation to prognosis in human breast cancer.

Aim: To explore the role of RanBP9 in breast cancer. Materials & methods: Oncomine, TIMER, GEPIA, UALCAN, c-BioPortal databases and tissue microarray analysis were used in this study. Results: The expression level of RanBP9 is elevated in breast cancer tissues, which is associated with poor prognosis in breast cancer patients. RanBP9 exhibits genetic alterations and a decreased methylation level in cancer tissues. RanBP9 may also regulate cell cycle progression and is linked to tumor purity and the infiltrating levels of immune cells. Conclusions:RanBP9 may correlate with prognosis and immune infiltration in breast cancer, laying the foundation for future studies on the potential role of RanBP9 in breast cancer.

Lay abstract RanBP9 has diverse function in various tumor types. However, the role of RanBP9 in breast cancer remains to be explored. In this study, we investigated the gene expression of RanBP9 using databases and clinical samples. We found the expression level of RanBP9 is raised in breast cancer tissues and is associated with poor prognosis for breast cancer patients. RanBP9 may be involved in the regulation of the cell cycle and related to tumor immunity. Overall, we found that RanBP9 may correlate with prognosis and immune infiltration of breast cancer, laying the foundation for future studies on the potential role of RanBP9 in breast cancer.

Transformation of advanced lung adenocarcinoma to acquired T790M resistance mutation adenosquamous carcinoma following tyrosine kinase inhibitor: a case report.

BACKGROUND: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are recommended for patients with non-small cell lung cancer with EGFR mutations. However, acquired resistance to EGFR-TKIs seems inevitable and the mechanism of drug resistance has not been fully defined. There is no effective treatment for patients with advanced lung adenocarcinoma who are resistant to TKIs owing to pathologic type conversion. CASE PRESENTATION: We report a patient who was initially diagnosed with lung adenocarcinoma. At first, she was sensitive to the first-generation TKI icotinib. After 17 months of treatment, the patient acquired resistance to icotinib. Moreover, after tumor resection, immunohistochemical analysis showed pathologic change from adenocarcinoma to adenosquamous carcinoma, and next-generation sequencing technology discovered EGFR exon19 p.745-750 del, exon20 p.T790M, and KMT2C exon 18 p.R973G mutations. After video-assisted tumor resection, the patient is receiving osimertinib (AZD 9291). Current overall survival is 60 months. CONCLUSIONS: Surgical intervention may prolong survival time in patients with acquired TKI resistance, especially when there is no evidence of metastasis.

Foxp3 TSDR Hypermethylation Is Correlated with Decreased Tregs in Patients with Unexplained Recurrent Spontaneous Abortion.

A decline of T regulatory cell (Treg) number and function is associated with unexplained recurrent spontaneous abortion (URSA). However, the mechanism of downregulation of Tregs in URSA patients is still unknown. This study aimed to investigate the changes of Tregs in URSA patients and the epigenetic regulation for these changes. Venous blood samples were collected from 20 patients with URSA and 20 healthy control subjects. Treg number and inhibitory capacity, and Foxp3 mRNA expression and Foxp3 TSDR methylation were compared between the 2 groups. Correlations between Treg frequency and inhibitory function and TSDR methylation status were examined by Spearman's correlation. The proportion of Tregs within the population of CD4+ T cells and the expression of Foxp3 mRNA was significantly lower in URSA patients than in healthy control subjects. Tregs from URSA patients and healthy controls both significantly inhibited the cytotoxic activity of natural killer (NK) cells toward K562 targets; however, the inhibitory ability of Tregs from URSA patients was significantly lower than that from healthy controls. The methylation level of the Treg-specific demethylated region (TSDR) in the Foxp3 gene was significantly greater in URSA patients than in the controls, and the level of methylation was inversely correlated with the proportion of Tregs and Foxp3 mRNA expression in the peripheral blood. However, the methylation level was not correlated with the inhibitory function of Tregs. A decrease of Treg number and function may be related to the pathogenesis of URSA, and Foxp3 hypermethylation may be associated with the decreased Treg number.

Silencing of long non-coding RNA MEG3 alleviates lipopolysaccharide-induced acute lung injury by acting as a molecular sponge of microRNA-7b to modulate NLRP3.

We aimed to elucidate the roles of the long non-coding RNA (lncRNA) maternally expressed gene 3 (MEG3)/microRNA-7b (miR-7b)/NLR pyrin domain containing 3 (NLRP3) axis in lipopolysaccharide (LPS)-induced acute lung injury (ALI). Mouse alveolar macrophage NR8383 and mice were administrated with LPS to establish ALI models in vitro and in vivo. NLRP3 was silenced while miR-7b was overexpressed in LPS-induced NR8383 cell model of ALI. The interleukin-18 (IL-18) and IL-1ß, as well as caspase-1, tumor necrosis factor-α (TNF-α) and IL-6 protein levels were assayed. To further investigate the underlying mechanisms of NLRP3 in ALI, lncRNA MEG3 was silenced and miR-7b was overexpressed in LPS-induced NR8383 cell model of ALI, after which in vivo experiments were performed for further verification. NLRP3 was highly expressed in LPS-induced NR8383 cell model of ALI. Silencing NLRP3 or overexpressing miR-7b inhibited IL-18 and IL-1ß, as well as caspase-1, TNF-α and IL-6. LncRNA MEG3 could sponge miR-7b, and lncRNA MEG3 silencing or miR-7b overexpression downregulates NLRP3 expression, thus reducing IL-18 and IL-1ß, as well as caspase-1, TNF-α and IL-6 levels. The in vivo experiments further confirmed the aforementioned findings. Silencing lncRNA MEG3 augments miR-7b binding to NLRP3 and downregulates NLRP3 expression, which ultimately improves LPS-induced ALI.

An integrative investigation on significant mutations and their down-stream pathways in lung squamous cell carcinoma reveals CUL3/KEAP1/NRF2 relevant subtypes.

BACKGROUND: Molecular mechanism of lung squamous cell carcinoma (LUSC) remains poorly understood, hampering effective targeted therapies or precision diagnosis about LUSC. We devised an integrative framework to investigate on the molecular patterns of LUSC by systematically mining the genomic, transcriptional and clinical information. METHODS: We utilized the genomics and transcriptomics data for the LUSC cohorts in The Cancer Genome Atlas.. Both kinds of omics data for 33 types of cancers were downloaded from The NCI's Genomic Data Commons (GDC) (https://gdc.cancer.gov/about-data/publications/pancanatlas). The genomics data were processed in mutation annotation format (maf), and the transcriptomics data were determined by RNA-seq method. Mutation significance was estimated by MutSigCV. Prognosis analysis was based on the cox proportional hazards regression (Coxph) model. RESULTS: Significant somatic mutated genes (SMGs) like NFE2L2, RASA1 and COL11A1 and their potential down-stream pathways were recognized. Furthermore, two LUSC-specific and prognosis-meaningful subtypes were identified. Interestingly, the good prognosis subtype was enriched with mutations in CUL3/KEAP1/NRF2 pathway and with markedly suppressed expressions of multiple down-stream pathways like epithelial mesenchymal transition. The subtypes were verified by the other two cohorts. Additionally, primarily regulated down-stream elements of different SMGs were also estimated. NFE2L2, KEAP1 and RASA1 mutations showed remarkable effects on the subtype-determinant gene expressions, especially for the inflammatory relevant genes. CONCLUSIONS: This study supplies valuable references on potential down-stream processes of SMGs and an alternative way to classify LUSC.

Long-term safety of icotinib in patients with non-small cell lung cancer: a retrospective, real-world study.

BACKGROUND: Lung cancer is a global health problem with a high mortality, and the development of target therapy has led to a revolution in the treatment of lung cancer in recent years. Favorable efficacy and safety of icotinib have been demonstrated in patients with non-small cell lung cancer (NSCLC). Currently, minimal data are available to describe the long-term safety of icotinib in NSCLC patients. METHODS: We reviewed the safety data from 1,321 advanced NSCLC patients who were treated with icotinib. The primary endpoint was the long-term safety, defined as any adverse drug reactions (ADRs) occurred after 6 months of icotinib administration. RESULTS: Fewer ADRs were noticed over 6 month administration of icotinib than within 6 months in overall population (24.3% vs. 65.4%), and elderly patients (23.6% vs. 66.9%). The majority of ADRs were grade 1-2 in severity over 6 month exposure of icotinib in overall population as well as elderly patients. In overall population, the most common ADRs of icotinib during long-term use were rash (16.4%) and diarrhea (5.3%), while the incidences were 31.8% and 13.2% in the induction period, respectively. In elderly population, the most common ADRs of icotinib during long-term use were rash (15.7%) and diarrhea (4.7%), while the incidences were 27.8% and 14.9% in the induction period, respectively, and more inching was observed in the induction period as compared with long term use (6.3% vs. 0.3%). CONCLUSIONS: There was an evidence of decreased frequency of icotinib-induced ADRs over time, and icotinib was well-tolerated in elderly NSCLC patients.

MiR-361 targets Yes-associated protein (YAP) mRNA to suppress cell proliferation in lung cancer.

Yes-associated protein (YAP) contributes to the development of multiple tumors, but the post-transcription modulation of YAP remains unexplored. Here, we present a new regulatory microRNA of YAP, miR-361, which directly targets YAP to inhibit cell proliferation in lung cancer. We used bioinformatics to predict that miR-361 could target 3'-untranslated region (3'UTR) of YAP mRNA. Luciferase reporter gene assays demonstrated that miR-361 could decrease the luciferase activities of 3'UTR vector of YAP. Furthermore, YAP expression was obviously abated by miR-361 using RT-PCR and immunoblotting in lung cancer A549 cells. In terms of function, MTT and colony formation analysis showed that ectopic miR-361 expression significantly suppressed cell proliferation in lung cancer. Notably, overexpressed YAP accelerated miR-361-bated proliferation of lung cancer cells. MiR-361 inhibitor promoted cell proliferation in lung cancer, but YAP RNA interference reversed miR-361 inhibitor-driven cell proliferation. Interestingly, miR-361 was capable of affecting the cell cycle in lung cancer progression. Finally, the negative correlation of miR-361 with YAP was found in clinical human lung cancer tissues. In conclusion, miR-361 targets 3'UTR of YAP mRNA to depress the proliferation of lung cancer cells.

The feasibility and advantage of uniportal video-assisted thoracoscopic surgery (VATS) in pulmonary lobectomy.

BACKGROUND: Ongoing improvements in technique and instruments for video-assisted thoracoscopic surgery (VATS) have made minimally-invasive uniportal VATS lobectomy a reality. However, the outcomes of the procedure are still under investigation, and at present, uniportal VATS lobectomy is performed infrequently at most hospitals. We have therefore reviewed our outcomes with this procedure in an attempt to validate its safety, efficacy, and feasibility. METHODS: We retrospectively analyzed and compared perioperative data for patients who underwent uniportal, two-port, and traditional three-port VATS lobectomy between January 2015 and December 2015 at our hospital. RESULTS: Among 257 patients who had successful VATS lobectomy during the study period, 73 underwent uniportal VATS, 86 underwent two-port VATS, and 98 underwent traditional three-port VATS. There were no surgical or 30-day postoperative mortalities, and no significant differences in operative times, blood loss, number of lymph nodes retrieved and nodal stations explored, drainage times, length of hospital stay, or postoperative complications among the three groups. The visual analogue scale (VAS) pain scores were significantly lower in the uniportal VATS group after surgery (P < 0.05). CONCLUSIONS: Uniportal VATS lobectomy is a safe and feasible surgical procedure that is associated with decreased surgical trauma and less postoperative pain compared to traditional VATS. Further long term follow-up analyses in large numbers of patients are ongoing.

The stability and controlled release of I-ascorbic acid encapsulated in poly (ethyl-2-cyanoacrylate) nanocapsules prepared by interfacial polymerization of water-in-oil microemulsions.

The L-ascorbic acid (AA) was encapsulated into biodegradable and biocompatible poly(ethyl-2-cyanoacrylate) (PECA) nanocapsules by interfacial polymerization of water-in-oil (W/O) microemulsions. The influences of surfactant concentration, pH value of the dispersed aqueous phase, and W/O ratio on nanocapsule size were discussed. The stability and in vitro release of encapsulated AA were also investigated. The results show that nanocapsules could be obtained under the conditions with low pH value, high fraction of aqueous phase, and appropriate surfactant concentration. The encapsulated AA was protected by nanocapsules from oxidation and presented superior storage stability in aqueous medium than pure AA. Releasing AA from the inner core of nanocapsules could be controlled by adjusting the enzyme hydrolysis extent of the PECA wall.

Alpinetin inhibits lung cancer progression and elevates sensitization drug-resistant lung cancer cells to cis-diammined dichloridoplatium.

OBJECTIVE: Alpinetin is a novel flavonoid that has demonstrated potent antitumor activity in previous studies. However, the efficacy and mechanism of alpinetin in treating lung cancer have not been determined. METHODS: We evaluated the impact of different doses and durations of alpinetin treatment on the cell proliferation, the apoptosis of lung cancer cells, as well as the drug-resistant lung cancer cells. RESULTS: This study showed that the alpinetin inhibited the cell proliferation, enhanced the apoptosis, and inhibited the PI3K/Akt signaling in lung cancer cells. Moreover, alpinetin significantly increased the sensitivity of drug-resistant lung cancer cells to the chemotherapeutic effect of cis-diammined dichloridoplatium. Taken together, this study demonstrated that alpinetin significantly suppressed the development of human lung cancer possibly by influencing mitochondria and the PI3K/Akt signaling pathway and sensitized drug-resistant lung cancer cells. CONCLUSION: Alpinetin may be used as a potential compound for combinatorial therapy or as a complement to other chemotherapeutic agents when multiple lines of treatments have failed to reduce lung cancer.

Airway Reconstruction with Autologous Pulmonary Tissue Flap and an Elastic Metallic Stent.

To pursue a suitable central airway replacement, we conducted central airway reconstruction using autologous pulmonary tissue flaps lined with alloy stents in five patients after extensive tracheal resection. Preoperative and postoperative arterial blood gas analysis and pulmonary function tests were used to evaluate efficacy of this technique. All patients demonstrated improved arterial blood gas values and pulmonary function. Follow-up bronchoscopy and chest computed tomography scan showed that each reconstructed trachea lacked swing or structural damage, and that each transplanted pulmonary tissue flap had ample blood circulation. After as long as 84 months follow-up, four patients reported no complications, although one patient died from severe hemoptysis 14 months after the surgery. The application of central airway reconstruction using an autologous pulmonary tissue flap lined with an elastic metallic stent provides a promising alternative for patients with thoracic tracheal defects.

Loss of RhoA expression prevents proliferation and metastasis of SPCA1 lung cancer cells in vitro.

Lung cancer is the leading cause of cancer-related death worldwide, mainly due to its highly metastatic properties. Previously, we reported an inverse correlation between Rho-kinase inhibitor and the progression of the lung cancer cells. The purpose of this study was to investigate the effects of RhoA on the proliferation, adhesion, invasion, and migration of SPCA1 lung carcinoma cells and to explore the underlying molecular mechanisms. RNA interference was used to downregulate RhoA expression in these cells. Through G418 screening, we generated SPCA1 lung cancer cell lines with stable RhoA silencing. We then observed the cell behaviour, and used matrix metalloproteinase (MMP) activity and western blot assays to evaluate the underlying molecular mechanisms. The proliferation, adhesion, migration, and invasion of SPCA1 lung cancer cells were decreased after knockdown of RhoA. At the molecular level, the total amounts of active MMP2 and MMP9 were decreased by about 17.21% (P<0.05) and 45.32% (P<0.01), respectively. Myosin phosphatase targeting subunit 1 phosphorylation (P-MYPT1) was reduced by 36.16% (P<0.05). Taken together, our findings show that the knockdown of RhoA prevents proliferation and metastasis in SPCA1 lung cancer cells. Changes in MMP2, MMP9, and P-MYPT1 levels and activity might be some of the molecular mechanisms underlying these effects.

The Rho-kinase inhibitor inhibits proliferation and metastasis of small cell lung cancer.

The purpose of this study was to investigate the effects of Rho-kinase inhibitor on the growth, proliferation, apoptosis, adhesion, invasion and migration of NCI-H446 small cell lung cancer cells and to explore the underlying molecular mechanisms involved in this process. After treatment to NCI-H446 small cell lung cancer cells with Fasudil, a Rho-kinase inhibitor, cell biological behaviors were observed. Matrix metalloproteinase activity and Western blot assay were used to evaluate underlying molecular mechanisms. The IC50 of Fasudil to NCI-H446 small cell lung cancer cells was approximately 0.86 mg/ml (95% confidence limits: 0.65-1.17 mg/ml). After treatment with 0.75 mg/ml Fasudil, the ability of NCI-H446 small cell lung cancer cells, including growth, proliferation, adhesion, migration, and invasion were decreased, while their apoptosis was increased significantly. On the molecular level, the total amounts of active MMP2 and MMP9 were decreased about 20.5% (P<0.05) and 57.5% (P<0.01) respectively. Myosin phosphatase targeting subunit 1 phosphorylation (P-MYPT1) was reduced by 27.9% (P<0.05). The activation of caspase-3, and PARP cleavage in experimental group were significantly higher than those in normal control group (P<0.01). Meanwhile, treatment with Fasudil led to a remarkable reduction of the phosphorylated STAT3 (P-STAT3) (P<0.01). Taken together, our findings show that Fasudil prevents the growth, metastasis and induces apoptosis of NCI-H446 small cell lung cancer cells by inhibiting the Rho/Rho-kinase pathway. Changes in MMP2, MMP9, P-MYPT1, caspase-3, PARP cleavage and P-STAT3 may be one of its molecular mechanisms.

[Experimental use of pulmonary flap with alloy stent for the reconstruction of trachea and esophagus].

OBJECTIVE: To study the feasibility of applying autogenous pulmonary tissue flap with alloy stent to correct the defects of trachea and esophagus. METHODS: Twenty-four dogs were divided into tracheal and esophageal groups. Bronchus was ligated to prepare a pulmonary flap. And a defect of 3 - 4 cm long and 1/2 - 2/3 perimeter was made in tracheal or esophageal wall. Pulmonary arteries and veins were protected. Then the pulmonary gas was emitted to create a pulmonary tissue flap. The defect was repaired with a pulmonary flap with a self-expanded stent inside. The gross appearance, histological appearance, CT and barium X-ray films were observed at Weeks 2, 4, 6 and 8 post-operation. RESULTS: Eighteen experimental dogs survived over 2 weeks. Anastomotic leak was the main cause of death. Two dogs died of perforation of ulcer in esophageal group. Reliable cicatrisation was observed between the pulmonary tissue flap and damage area. A quick growth of new tracheal and esophageal epithelium was observed from periphery area to central area. During the first 2 weeks, a little epithelization was observed at free edge of anastomosis equivalent to 1 - 2 layers of new epithelial cells. At weeks 4 - 6 post-operation, the internal surface of defect was covered with 3 - 5 layers of epithelial cells. At Weeks 8 - 10 post-operation, the luminal surface was covered with 6 - 8 layers of stratified epithelial cells. More ulcers could be observed on the surface of pulmonary tissue flap in esophageal group. In pulmonary flap, massive fibrous tissue proliferated and fibroblasts were active, but no necrosis occurred. CT and barium X-ray showed no obstruction in anastomotic stoma. CONCLUSION: With an excellent compatibility with epithelial cells of trachea and esophagus, the autogenous pulmonary tissue flap can support the mucosal crawl in the defect of trachea and esophagus. When combined with alloy stent, it may be a choice procedure for reconstructing the defect of trachea and esophagus.

Micelle formation and drug release behavior of polypeptide graft copolymer and its mixture with polypeptide block copolymer.

Self-association behavior of polypeptide graft copolymer and its mixture with polypeptide block copolymer and drug carrier capability of the formed micelles was examined. The results gained through fluorescence spectroscopy, transmission electron microscopy and nuclear magnetic resonance spectroscopy revealed that both polypeptide graft copolymer and its mixture with polypeptide block copolymer can self-assemble to form polymeric micelles in aqueous media. The molecular structure of the graft copolymer and blending the graft with block copolymer exert marked effects on the critical micelle concentration and the shape of formed micelles. It was found that the hydrophobic inner core of the micelles formed either by graft copolymer or mixture of graft and block copolymers can act as an incorporation site for the hydrophobic drugs. The drug loading content of the graft copolymer micelles tends to be larger when the content of the polypeptide segments in the copolymer increases. The results obtained from the drug-release studies showed that the drug-release rates are dependent on the chemical nature of the graft copolymer, the composition of the graft and block copolymer mixture, and also the pH value of the release media.

[Experimental research of esophagus replacement with pulmonary flap in dogs].

OBJECTIVE: To apply self-pulmonary tissue flap to reconstruct esophagus directly or with alloy stent in this research. METHODS: Twenty-four dogs were divided into two groups, middle bronchus was ligated to prepare pulmonary flap and incised, a 4 to 6 cm long and 1/2 to 2/3 perimeter defect was made in esophageal wall. Esophagus defect was repaired only with pulmonary flap (experimental group) and with pulmonary flap having self-expanded stent inside (control group). The gross appearance, histological appearance and barium X-ray films were observed at 2,4,6,8, 10 and 12 weeks after operation. RESULTS: Two dogs died of anastomotic leak in experimental group, three dogs died of anastomotic leak and two dogs died of perforation of ulcer in control group. The growth of esophagus epithelium was observed from periphery area to dental area after 8 to 10 weeks of operation. In pulmonary flap mass fibrous tissue proliferated and fibroblasts were active, but no necrosis occurred. Barium X-ray of regenerated esophagus showed that mild stenosis and weakened peristalsis were observed in the middle of esophagus replacement, and that no obstruction, leakage, and dilation above anastomotic stoma occurred. CONCLUSION: Pulmonary tissue flap can well support the mucosa crawl in the defect of esophagus. It is necessary to find a more suitable and satisfied stent for repairing segmental defect.