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The treatment of long-tracheal lesion is difficult because there are currently no viable grafts for tracheal replacement. To solve this problem, we have developed an autologous Tissue-Engineered Trachea (aTET), which is made up of collagenous tissues and cartilage-like structures derived from rat chondrocytes. This graft induced successful long-term survival in a small-animal experiment in our previous study. In this study, we investigated the regeneration process of an aTET to attain reproducible success. We prepared an aTET by using a specially designed mold and performed patch tracheoplasty with an aTET. We assigned twenty-seven rats to three groups according to the three types of patch grafts used: aTET patches (the aTET group), fresh tracheal autograft patches (the Ag group), or polylactic acid and polycaprolactone copolymer sheets (the PPc group). In each group, gross and histological evaluations were performed at 1 month (n = 3), 3 months (n = 3), and 6 months (n = 3) after implantation. We obtained high survival rates in all groups, but only the PPc group attained thick tracheal walls with granular tissues and no tracheal regeneration. On the other hand, the aTET and Ag groups reproducibly achieved complete tracheal regeneration in 6 months. So, an aTET could be a promising candidate for tracheal regeneration grafts. [ABSTRACT FROM AUTHOR]

Congenital pulmonary airway malformation (CPAM) is a developmental malformation that affects the lung parenchyma, especially terminal respiratory bronchioles. This paper reports a case of an infant diagnosed with CPAM who underwent stapleless thoracoscopic lobectomy using Hem-o-Lok clips®. Computed tomography showed cystic pulmonary lesions in the left lower lobe. Thoracoscopic lobectomy was performed at the age of 1 year and 3 months. During surgery, the hilar vasculature was treated using either Hem-o-Lok® clips or a LigaSure vessel sealing system. The lower lobe bronchus was divided using double Hem-o-Lok® clips proximally. The surgery was successfully completed. The patient's postoperative course was uneventful, and there were no complications. This technique can be easily performed as a thoracoscopic lobectomy with the potential benefits of safe and effective procedures for bronchus closure and vascular sealing in the small working space of pediatric patients. [ABSTRACT FROM AUTHOR]

Lung hypoplasia and pulmonary hypertension are the major causes of mortality in neonates with congenital diaphragmatic hernia (CDH). Although the prostaglandin pathway plays a pivotal role in lung development, the reported efficacy of postnatal prostaglandin agonist treatment is suboptimal. We hypothesized that prenatal treatment with ONO-1301SR, a slow-release form of a novel synthetic prostacyclin agonist with thromboxane inhibitory activity, might enhance the development of lungs exhibiting hypoplasia in the fetal period. On embryonic day (E) 9.5, nitrofen was given to pregnant Sprague-Dawley rats to establish a CDH-related lung hypoplasia model, whereas normal rats received the vehicle only. The same day, either ONO-1301SR or a placebo was also randomly administered. On E21.5, the fetuses of the normal group and those exhibiting CDH were analyzed. Prenatal ONO-1301SR administration had no influence on the incidence of nitrofen-induced CDH. The lung-to-body weight ratio in the CDH+ONO group was greater than that in the CDH group. Histologically, the medial wall in the CDH+ONO group was two-thirds thinner than that in the CDH group. In addition, the number of Ttf-1-positive cells and the capillary density were ≥1.5 times greater in the CDH+ONO group than in the CDH group, and this increase was associated with higher expression of vascular endothelial growth factor and stromal cell-derived factor in the CDH+ONO group, suggesting enhanced development of the alveolar and capillary networks. Thus, prenatal ONO-1301SR was protective against the progression of lung hypoplasia associated with CDH in a nitrofen-induced rat model, indicating the potential of this treatment for pathologies exhibiting lung hypoplasia. [ABSTRACT FROM AUTHOR]

Macrophage-mediated xenogeneic rejection is a major immunological obstacle. We recently reported that membrane-type surfactant protein-D (SP-D) on swine endothelial cells (SECs) suppressed macrophage-mediated rejection. Similar to SP-D, the carbohydrate recognition domain of surfactant protein-A (SP-A) can induce inhibitory signals in effector cells. The present study aimed to examine the suppressive effect of SP-A on macrophage-mediated xenogeneic rejection. Naive SECs and SPA-transfected SECs (SEC/SP-A) were co-cultured with THP-1 cells and cytotoxicity was evaluated. To investigate the effect of SP-A on phagocytosis, human macrophages were co-cultured with SEC or SEC/SP-A, and the extent of phagocytosis and production of reactive oxygen species were assessed via flow cytometry. The mRNA expression levels of inflammatory cytokines in macrophages were determined using reverse transcription-PCR. Additionally, the effects of THP-1-Lucia NF-κB cells on transcription factors were evaluated. The cytotoxicity and phagocytosis of SEC/SP-A were significantly decreased compared with those of naive SEC. Furthermore, the co-culture of human macrophages with SEC/SP-A decreased reactive oxygen species production, and the mRNA expression levels of TNFα were decreased in macrophages, whereas those of IL-10 were increased. In addition, NF-κB transcription was decreased in SEC/SP-A compared with that in SEC. In conclusion, the ectopic expression of human SP-A in porcine cells represents an attractive method for suppressing macrophage-mediated cytotoxicity. [ABSTRACT FROM AUTHOR]

Rhabdomyosarcoma ( RMS) is a malignant mesenchymal tumor and the most common soft tissue sarcoma in children. Because of several complications associated with intensive multimodal therapies, including growth disturbance and secondary cancer, novel therapies with less toxicity are urgently needed. C-type natriuretic peptide ( CNP), an endogenous peptide secreted by endothelial cells, exerts antiproliferative effects in multiple types of mesenchymal cells. Therefore, we investigated whether CNP attenuates proliferation of RMS cells. We examined RMS patient samples and RMS cell lines. All RMS clinical samples expressed higher levels of guanylyl cyclase B ( GC-B), the specific receptor for CNP, than RMS cell lines. GC-B expression in RMS cells decreased with the number of passages in vitro. Therefore, GC-B stable expression lines were established to mimic clinical samples. CNP increased cyclic guanosine monophosphate ( cGMP) levels in RMS cells in a dose-dependent manner, demonstrating the biological activity of CNP. However, because cGMP is quickly degraded by phosphodiesterases ( PDEs), the selective PDE5 inhibitor sildenafil was added to inhibit its degradation. In vitro, CNP, and sildenafil synergistically inhibited proliferation of RMS cells stably expressing GC-B and decreased Raf-1, Mitogen-activated protein kinase kinase ( MEK), and extracellular signal-regulated kinase ( ERK) phosphorylation. These results suggested that CNP in combination with sildenafil exerts antiproliferative effects on RMS cells by inhibiting the Raf/ MEK/ ERK pathway. This regimen exerted synergistic effects on tumor growth inhibition without severe adverse effects in vivo such as body weight loss. Thus, CNP in combination with sildenafil represents a promising new therapeutic approach against RMS. [ABSTRACT FROM AUTHOR]

Background: The association of complement with the progression of acute T cell mediated rejection (ATCMR) is not well understood. We investigated the production of complement components and the expression of complement regulatory proteins (Cregs) in acute T-cell mediated rejection using rat and human renal allografts. Methods: We prepared rat allograft and syngeneic graft models of renal transplantation. The expression of Complement components and Cregs was assessed in the rat grafts using quantitative real-time PCR (qRT-PCR) and immunofluorescent staining. We also administered anti-Crry and anti-CD59 antibodies to the rat allograft model. Further, we assessed the relationship between the expression of membrane cofactor protein (MCP) by immunohistochemical staining in human renal grafts and their clinical course. Results: qRT-PCR results showed that the expression of Cregs, CD59 and rodent-specific complement regulator complement receptor 1-related gene/protein-y (Crry), was diminished in the rat allograft model especially on day 5 after transplantation in comparison with the syngeneic model. In contrast, the expression of complement components and receptors: C3, C3a receptor, C5a receptor, Factor B, C9, C1q, was increased, but not the expression of C4 and C5, indicating a possible activation of the alternative pathway. When anti-Crry and anti-CD59 mAbs were administered to the allograft, the survival period for each group was shortened. In the human ATCMR cases, the group with higher MCP expression in the grafts showed improved serum creatinine levels after the ATCMR treatment as well as a better 5-year graft survival rate. Conclusions: We conclude that the expression of Cregs in allografts is connected with ATCMR. Our results suggest that controlling complement activation in renal grafts can be a new strategy for the treatment of ATCMR. [ABSTRACT FROM AUTHOR]

Background. Treating functional gastrointestinal disorders is extremely difficult. We herein report the effect of the oral administration of Ninjinto (NJT, ginseng decoction), a traditional Japanese Kampo medicine, on chronic intestinal failure. Patients and Methods. Seven patients with chronic intestinal failure treated with NJT were evaluated in this study. The primary diseases included chronic intestinal pseudoobstruction (CIPO: n=4), short bowel syndrome (SBS: n=2), and intestinal atresia n=1. All patients orally received NJT extract granules at a dose of 0.3 g/kg BW per day. The treatment outcomes were then assessed according to the patients’ symptoms and consecutive abdominal X-ray findings. Results. The targeted symptoms were abdominal distension in four patients, diarrhea in three patients, and frequent hospitalization due to infections in two patients. An improvement in the symptoms was observed in six of the seven patients, whereas one patient with SBS did not show any improvement. An improvement in an abdominal roentgenogram was observed in the four patients with remarkably dilated bowel loops due to CIPO. Conclusions. NJT may be effective in controlling functional gastrointestinal disorders associated with chronic intestinal failure. The use of Kampo medicine in the field of pediatric surgery may help to improve the quality of life in children suffering from such conditions. [ABSTRACT FROM AUTHOR]

Cancer stem cells (CSCs) are defined as a small population of cancer cells with the properties of high self-renewal, differentiation, and tumor-initiating functions. Recent studies have demonstrated that aldehyde dehydrogenase 1 (ALDH1) is a marker for CSCs in adult cancers. Although CSCs have been identified in some different types of pediatric solid tumors, there have been no studies regarding the efficacy of ALDH1 as a marker for CSCs. Therefore, in order to elucidate whether ALDH1 can be used as a marker for CSCs of pediatric sarcoma, we examined the characteristics of a population of cells with a high ALDH1 activity (ALDH1high cells) in rhabdomyosarcoma (RMS), the most common soft tissue sarcoma in children. We used the human embryonal RMS (eRMS) cell lines RD and KYM-1, and sorted the cells into two subpopulations of ALDH1high cells and cells with a low ALDH1 activity (ALDH1low cells). Consequently, we found that the ALDH1high cells comprised 3.9% and 8.2% of the total cell population, respectively, and showed a higher capacity for self-renewal and tumor formation than the ALDH1low cells. With regard to chemoresistance, the survival rate of the ALDH1high cells was found to be higher than that of the ALDH1low cells following treatment with chemotherapeutic agents for RMS. Furthermore, the ALDH1high cells exhibited a higher degree of pluripotency and gene expression of Sox2, which is one of the stem cell markers. Taken together, the ALDH1high cells possessed characteristics of CSCs, including colony formation, chemoresistance, differentiation and tumor initiation abilities. These results suggest that ALDH1 is a potentially useful marker of CSCs in eRMS. [ABSTRACT FROM AUTHOR]

Aim : To show the clinical, physiological and histological characteristics in GER with cow's milk intolerance Methods : Nine children with GERD tess than 6 years old who had at least recurrent vomiting as ther symptom were studied. Endoscopic and histologic diagnosis, gastric scintigraphy and 24 h-pH monitoring, blood tests were done. Results : All children had cow's milk intolerance clinically. Acid reflux in esophagus and delayed gastric emptying were shown. Duodenitis with histamine and substance P and mild esophagitis were present in these children. Conclusions : Duodenitis with chemical mediators secondary to cow's milk intolerance may play an important role for the cause of GER in children. [ABSTRACT FROM AUTHOR]