Go Hatachi

Click-coated, heparinized, decellularized vascular grafts.

A novel method enabling the engineering of a dense and appropriately oriented heparin-containing layer on decellularized aortas has been developed. Amino groups of decellularized aortas were first modified to azido groups using 3-azidobenzoic acid. Azide-clickable dendrons were attached onto the azido groups through alkyne-azide click chemistry, affording a tenfold amplification of adhesions sites. Dendron end groups were finally decorated with end-on modified heparin chains. Heparin chains were oriented like heparan sulfate groups on native endothelial cells surface. X-ray photoelectron spectroscopy, nuclear magnetic resonance imaging, mass spectrometry and Fourier transform infrared FTIR spectroscopy were used to characterize the synthesis steps, building the final heparin layered coatings. The continuity of the heparin coating was verified using fluorescent microscopy and histological analysis. The efficacy of heparin linkage was demonstrated with factor Xa anti-thrombogenic assay and platelet adhesion studies. The results suggest that oriented heparin immobilization to decellularized aortas may improve the in vivo blood compatibility of decellularized aortas and vessels.

The poly(adenosine diphosphate-ribose) polymerase inhibitor PJ34 reduces pulmonary ischemia-reperfusion injury in rats.

Background Ischemia-reperfusion (I/R) injury after lung transplantation causes alveolar damage, lung edema, and acute rejection. Poly(adenosine diphosphate-ribose) polymerase (PARP) is a single-stranded DNA repair enzyme that induces apoptosis and necrosis after DNA damage caused by reactive oxygen species. We evaluated tissue protective effects of the PARP inhibitor (PARP-i) PJ34 against pulmonary I/R injury. Methods Rats (total n=45) underwent a thoracotomy with left hilar isolation and saline administration (sham group) or thoracotomy with hilar clamping and saline administration (I/R group) or PJ34 administration (PARP-i group). Parameters were measured for 7 days after reperfusion. Results Pathologic analysis revealed that reperfusion injury was drastically suppressed in the PARP-i group 2 days after reperfusion. Terminal deoxynucleotide transferase-mediated deoxyuridine triphosphate nick-end labeling–positive cells were significantly decreased in the PARP-i group compared to the I/R group (P<0.05). Accordingly, the wet-to-dry lung ratio in the I/R group was significantly higher compared with the PARP-i group (P=0.025). Four hours after reperfusion, serum tissue necrosis factor-&agr; and interleukin-6 were significantly suppressed in the PARP-i group compared with the I/R group (P<0.05). Serum derivatives of reactive oxygen metabolites increased quickly and remained high in the I/R and PARP-i groups from 4 hr until 7 days after reperfusion. Interestingly, the serum biologic antioxidant potential in the PARP-i group was significantly higher than that in the I/R group from day 2 until day 7. Conclusion The PARP-i decreased inflammation and tissue damage caused by pulmonary I/R injury. These beneficial effects of the PARP-i may be correlated with its antioxidative efficacy.

The evolution of bronchoplasty and broncho-angioplasty as treatments for lung cancer: evaluation of 30 years of data from a single institution

OBJECTIVESnThe purpose of this study was to evaluate the factors contributing to the outcomes of bronchoplasty for lung cancer by analysing a single institutions data for a 30-year period.nnnMETHODSnA retrospective review of 213 patients who underwent bronchoplasty for lung cancer between 1980 and 2010 was undertaken. The patients were divided into two groups by the date of surgery: the first period was 1980-95, and the second period was 1996-2010.nnnRESULTSnBronchoplasty and broncho-angioplasty were performed in 100 (75.8%) and 32 (24.2%) patients, respectively, in the first period and 61 (75.3%) and 20 (24.7%) patients, respectively, in the second period. Overall 90-day operative morbidity and mortality rates were 25.8 and 9.8%, respectively, in the first period and 45.7 and 2.5%, respectively, in the second period. Thirty-day mortality rates were 6.8% in the first period and 0% in the second period. Five-year survival was 41.1% (n = 132) in the first period and 61.5% (n = 81) in the second period (P = 0.0003). Comparing bronchoplasty and broncho-angioplasty, the 5-year survival was 45.6 and 26.5%, respectively, in the first period (P = 0.0048) and 60.9 and 62.1%, respectively, in the second period (P = 0. 8131). Using multivariate analysis to identify potential prognostic factors, the type of operation (broncho-angioplasty), postoperative complications and histology (non-squamous cell carcinoma) were significant factors affecting survival in the first period, but none of the factors significantly affected survival in the second period. When the rates of pN2 or N3 histological type disease were compared in each period, the rate of pN2 or N3 disease in non-squamous cell carcinoma was 51.4% in the first period and 45.5% in the second period; both were significantly higher than in squamous cell carcinoma (31.6 and 16.9%, respectively; P = 0. 0365 and 0.0073).nnnCONCLUSIONSnThe present study suggests that progress in the preoperative staging system and perioperative medical management, as well as surgery, has contributed to current improvements in patients undergoing bronchoplasty and broncho-angioplasty. However, since nodal status in non-squamous cell carcinoma is not precisely evaluated before the operation, the indication for bronchoplasty should be considered carefully.

Ventilation-Based Decellularization System of the Lung

Abstract The demand for donated organs greatly exceeds the availability. Alternatives to organ donation, such as laboratory-engineered organs, are therefore being developed. One approach is to decellularize the organ and reseed it with selected cells, ideally from the organ recipient. Organ decellularization has typically been attempted by the administration of detergents into vessels such as the portal vein in the liver. However, in the case of the lung, the airway provides another potential administration route, because it has a wide contact area between cells and detergents in the tracheal tree and alveoli. In the present study, we introduce a novel ventilation-based decellularization system for the lung and compare its efficacy to ordinary decellularization systems administering detergent through the pulmonary artery. Rat lungs were decellularized using 500u2009mL of 3-[(3-cholamidopropyl) dimethylammonio]-1-Propanesulfonate (CHAPS) decellularization solution administrated through the pulmonary artery (vessel group) or through the trachea (airway group). The vessel group was infused CHAPS solution using a gravitational pressure head of 20u2009cmH2O. The airway group was infused with the detergent using negative pressure and positive end-expiratory pressure, for a volume 10cc with each inspiration in a bioreactor. Pathological and immunohistochemical findings indicated that components of the extracellular matrix (ECM), including proteoglycans, elastic fibers, fibronectin, and laminin, were more decreased in the airway group than in the vessel group. Western blot analysis showed that MHC class I antigen and β-actin were not detected in both decellularized groups. A collagen assay showed that collagen was 70% preserved in both groups compared to native lung. Glycosaminoglycan (GAG) and DNA assays showed that GAG and DNA contents were strongly diminished in both decellularized groups, but those contents were smaller in the airway group than in the vessel group. Accordingly, the alveolar wall was thinner on electron microscopy, and DNA remnants were not observed in the airway group. Infusion of red blood cells indicated that capillary walls were preserved without blood leakage in both groups. In conclusion, we describe a novel approach for decellularization through the airway that represents a more stringent method for both DNA and ECM removal, with capillary wall preservation.

Surgery or stereotactic body radiotherapy for elderly stage I lung cancer? A propensity score matching analysis

PurposeThe aim of this study was to compare the outcomes of surgery and stereotactic body radiotherapy (SBRT) for elderly clinical stage I non-small cell lung cancer (NSCLC) patients.MethodsPatients ≥80xa0years of age with clinical stage I NSCLC between August 2008 and December 2014 were treated either surgery or SBRT. Propensity score matching was performed to reduce bias in various clinicopathological factors.ResultsSurgery was performed in 57 cases and SBRT in 41 cases. In the surgery group, the operations included 34 lobectomies and 23 sublobar resections. In the SBRT group, 27 cases were given 48xa0Gy in 4 fractions, and 14 were given 60xa0Gy in 10 fractions. Similar characteristics were identified in age (82xa0years), gender (male:female ratio 2:1), tumor size (2.2xa0cm), carcinoembryonic antigen (3.6xa0ng/ml), Charlson comorbidity index (1), Glasgow prognostic scale (0), and forced expiratory volume in 1 s (1.7 L) after matching. Before matching, the 5-year overall survival (OS) in surgery (68.3%) was significantly better than that in SBRT (47.4%, pxa0=xa00.02), and the 5-year disease-specific survival (DSS) (94.1%, 78.2%, pxa0=xa00.17) was not significantly different between the groups. The difference in the 5-year OS became non-significant between the matched pairs (57.0%, 49.1%, pxa0=xa00.56).ConclusionsThe outcomes of surgery and SBRT for elderly patients with the early stage NSCLC were roughly the same.

Ratio of C-reactive protein to albumin is a prognostic factor for operable non-small-cell lung cancer in elderly patients

PurposeThe aim of this retrospective study was to evaluate inflammation-based scoring as a prognostic factor for operable non-small-cell lung cancer (NSCLC) in elderly patients.MethodsWe collected preoperative data from 108 patients aged above 80xa0years with NSCLC. Inflammation-based scoring systems, including the C-reactive protein to albumin ratio (CAR) and the Glasgow prognostic score (GPS), as well as other clinicopathological factors, were evaluated as potential prognostic factors.ResultsThe median patient age was 82 (range 80–93) years and the 5-year overall and disease-specific survival rates were 49.7 and 73.9%, respectively. The cut-off value for CAR was calculated using a receiver operator characteristics analysis and patients were dichotomized accordingly. Patients with a low CAR had significantly higher overall survival than those with a high CAR (<0.028; 65.2% vs. ≥0.028; 31.0%, respectively; pxa0<xa00.01). In univariate analysis, female gender, a low Charlson comorbidity index of 0 or 1 and a low CAR were significantly identified in overall survival. On multivariate analysis, a low CAR (pxa0=xa00.03, hazard ratio: 2.13, 95% confidence interval 1.074–4.295) was identified as a significant prognostic factor.ConclusionsThe preoperative CAR is a useful predictor of overall survival and could be a simple prognostic tool to help identify resectable NSCLC in elderly patients.

Transplantation of bioengineered rat lungs recellularized with endothelial and adipose-derived stromal cells

Bioengineered lungs consisting of a decellularized lung scaffold that is repopulated with a patient’s own cells could provide desperately needed donor organs in the future. This approach has been tested in rats, and has been partially explored in porcine and human lungs. However, existing bioengineered lungs are fragile, in part because of their immature vascular structure. Herein, we report the application of adipose-derived stem/stromal cells (ASCs) for engineering the pulmonary vasculature in a decellularized rat lung scaffold. We found that pre-seeded ASCs differentiated into pericytes and stabilized the endothelial cell (EC) monolayer in nascent pulmonary vessels, thereby contributing to EC survival in the regenerated lungs. The ASC-mediated stabilization of the ECs clearly reduced vascular permeability and suppressed alveolar hemorrhage in an orthotopic transplant model for up to 3u2009h after extubation. Fibroblast growth factor 9, a mesenchyme-targeting growth factor, enhanced ASC differentiation into pericytes but overstimulated their proliferation, causing a partial obstruction of the vasculature in the regenerated lung. ASCs may therefore provide a promising cell source for vascular regeneration in bioengineered lungs, though additional work is needed to optimize the growth factor or hormone milieu for organ culture.

Recruitment of Young Medical Apprentices (RYOMA) Project: A Comprehensive Surgical Education Program at a Local Academic Institute in Japan

OBJECTIVESnThe number of young surgeons in Japan has significantly decreased in recent years, which may lead to future problems in the medical field. Therefore, comprehensive training programs for young surgeons are needed.nnnDESIGNnRetrospective studynnnSETTINGnWe developed a specific education program called the Recruitment of Young Medical Apprentices (RYOMA) project.nnnPARTICIPANTSnWe performed this project between January 2008 and August 2013 on fourth- to sixth-year medical students and internship doctors. The RYOMA project included step-by-step surgical education programs on open and scopic procedures as dry, wet, and animal laboratory training. Our goal was to increase the number of young and specialist surgeons.nnnRESULTSnBased on an interview questionnaire answered by 90 medical students, most young students were interested in surgical training and several chose to become surgeons in the future. The most positive opinions regarding the field of surgery were the impressive results achieved with surgery, whereas negative opinions included the difficulty of the surgical skill, physical concerns related to difficult work environments, and the severity of surgical procedures. The present program has begun to resolve negative opinions through adequate training or simulations. Of the 19 medical students and internship doctors who attended the RYOMA project in 2008, 17 trainees (90%) were satisfied with this special surgical program and 16 (88%) showed interest in becoming surgeons. The number of participants considering the field of surgery increased between 2008 and 2013. Of 23 participants, 19 (83%) had a positive opinion of the program after the training.nnnCONCLUSIONSnGaining experience in surgical training from an early stage in medical school and step-by-step authorized education by teaching staff are important for recruiting students and increasing the number of young surgeons.

Bioengineered lungs generated from human iPSCs-derived epithelial cells on native extracellular matrix

The development of an alternative source for donor lungs would change the paradigm of lung transplantation. Recent studies have demonstrated the potential feasibility of using decellularized lungs as scaffolds for lung tissue regeneration and subsequent implantation. However, finding a reliable cell source and the ability to scale up for recellularization of the lung scaffold still remain significant challenges. To explore the possibility of regeneration of human lung tissue from stem cells in vitro, populations of lung progenitor cells were generated from human iPSCs. To explore the feasibility of producing engineered lungs from stem cells, we repopulated decellularized human lung and rat lungs with iPSC‐derived epithelial progenitor cells. The iPSCs‐derived epithelial progenitor cells lined the decellularized human lung and expressed most of the epithelial markers when were cultured in a lung bioreactor system. In decellularized rat lungs, these human‐derived cells attach and proliferate in a manner similar to what was observed in the decellularized human lung. Our results suggest that repopulation of lung matrix with iPSC‐derived lung epithelial cells may be a viable strategy for human lung regeneration and represents an important early step toward translation of this technology.

Scaffold-free trachea regeneration by tissue engineering with bio-3D printing

OBJECTIVESnCurrently, most of the artificial airway organs still require scaffolds; however, such scaffolds exhibit several limitations. Alternatively, the use of an autologous artificial trachea without foreign materials and immunosuppressants may solve these issues and constitute a preferred tool. The rationale of this study was to develop a new scaffold-free approach for an artificial trachea using bio-3D printing technology. Here, we assessed the circumferential tracheal replacement using scaffold-free trachea-like grafts generated from isolated cells in an inbred animal model.nnnMETHODSnChondrocytes and mesenchymal stem cells were isolated from F344 rats. Rat lung microvessel endothelial cells were purchased. Our bio-3D printer generates spheroids consisting of several types of cells to create 3D structures. The bio-3D-printed artificial trachea from spheroids was matured in a bioreactor and transplanted into F344 rats as a tracheal graft under general anaesthesia. The mechanical strength of the artificial trachea was measured, and histological and immunohistochemical examinations were performed.nnnRESULTSnTracheal transplantation was performed in 9 rats, which were followed up postoperatively for 23u2009days. The average tensile strength of artificial tracheas before transplantation was 526.3u2009±u2009125.7u2009mN. The bio-3D-printed scaffold-free artificial trachea had sufficient strength to transplant into the trachea with silicone stents that were used to prevent collapse of the artificial trachea and to support the graft until sufficient blood supply was obtained. Chondrogenesis and vasculogenesis were observed histologically.nnnCONCLUSIONSnThe scaffold-free isogenic artificial tracheas produced by a bio-3D printer could be utilized as tracheal grafts in rats.