Motoi Mukai

Reversal of the resistance to STI571 in human chronic myelogenous leukemia K562 cells.

STI571, an Abl‐specific tyrosine kinase inhibitor, selectively kills Bcr‐Abl‐containing cells in vitro and in vivo. However, some chronic myelogenous leukemia (CML) cell lines are resistant to STI571. We evaluated whether STI571 interacts with P‐glycopro‐tein (P‐gp) and multidrug resistance protein 1 (MRP1), and examined the effect of agents that reverse multidrug resistance (MDR) on the resistance to SI571 in MDR cells. STI571 inhibited the [125l]azidoagosterol A‐photolabeling of P‐gp, but not that of MRP1. K562/MDR cells that overexpress P‐gp were 3.67 times more resistant to STI571 than the parental Philadelphia‐chromosome‐positive (Ph+) CML K562 cells, and this resistance was most effectively reversed by cepharanthine among the tested reversing agents. The concentration of STI571 required to completely inhibit tyrosine phosphorylation in K562/MDR cells was about 3 times higher than that in K562 cells, and cepharanthine abolished the difference. In KB‐G2 cells that overexpress P‐gp, but not Bcr‐Abl, 2.5 μM STI571 partly reversed the resistance to vincristine (VCR), paclitaxel, etoposide (VP‐16) and actinomycin D (ACD) but not to Adriamycin (ADM) or colchicine. STI571 increased the accumulation of VCR, but not that of ADM in KB‐G2 cells. STI571 did not reverse resistance to any agent in KB/MRP cells that overexpress MRP1. These findings suggest that STI571 is a substrate for P‐gp, but is less efficiently transported by P‐gp than VCR, and STI571 is not a substrate for MRP1. Among the tested reversing agents that interact with P‐gp, cepharanthine was the most effective agent for the reversal of the resistance to STI571 in K562/ MDR cells. Furthermore, STI571 itself was a potent reversing agent for MDR in P‐gp‐expressing KB‐G2 cells.

Reversal of P-glycoprotein mediated multidrug resistance by a newly synthesized 1,4-benzothiazipine derivative, JTV-519

A newly synthesized 1,4-benzothiazipine derivate, 4-[3-(4-benzylpiperidin-1-yl) propionyl]-7-methoxy-2,3,4,5-tetrahydro-1, 4-benzothiazepine monohydrochloride (JTV-519) was examined for its ability to reverse P-glycoprotein (P-gp) and multidrug resistance protein 1 (MRP1) mediated multidrug resistance (MDR) in K562/MDR and KB/MRP cells, respectively. JTV-519 at 3 microM reversed the resistance of K562/MDR cells to vincristine (VCR), taxol, etoposide (VP16), adriamycin (ADM) and actinomycin D and at 0.5 or 1 microM reversed their resistance to STI571. JTV-519 at 10 microM enhanced the accumulation of ADM in K562/MDR cells to the level in parental K562 cells and inhibited the efflux of ADM from K562/MDR cells. Photoaffinity labeling of P-gp with 3H-azidopine was almost completely inhibited by 500 microM JTV-519. JTV-519 at 3 microM also partially reversed the resistance of KB/MRP cells to VCR and at 500 microM partially inhibited the photoaffinity labeling of MRP1 with (125)I-II-azidophenyl agosterol A (125I-azidoAG-A). These results suggest that JTV-519 reversed the resistance to the anti-cancer agents in P-gp and MRP1 overexpressing multidrug-resistant cells by directly binding to P-gp and MRP1, and competitively inhibiting transport of the anti-cancer agents.

Does the external appearance of a Meckel's diverticulum assist in choice of the laparoscopic procedure?

Abstract In the era of laparoscopic surgery, the resection of a Meckels diverticulum is a good indication for a laparoscopic procedure. In this paper, the relationship between the distribution of gastric heterotopia (GH) and the external appearance of the diverticulum was studied for the proper choice of the laparoscopic procedure. Symptomatic diverticula containing GH in eight patients were analyzed with regard to the distribution of gastric mucosa and the external appearance. While the long diverticula had the GH at the distal end, in the short diverticula it occurred in almost any area. For long diverticula, simple transverse resection with a stapling device is recommended. However, in short diverticula ileal resection with end-to-end anastomosis or wedge resection after exteriorization is recommended.

Spontaneous rupture of the stomach in preschool age children: a report of two cases.

The cases of two preschool-age children who suffered spontaneous gastric ruptures are reported herein. The first was a 2-year-old girl with tetralogy of Fallot, transferred to our hospital due to shock. A laparotomy was performed under the diagnosis of gastrointestinal perforation, and two perforations of the posterior wall of the gastric fundus were found. The second case, a 4-year-old girl who had previously experienced an episode of gastric dilatation, was admitted to our department with abdominal distention and vomiting. An abdominal X-ray film revealed a pneumoperitoneum, and an emergency laparotomy was performed, confirming a round rupture in the posterior wall of the stomach. Both patients had a satisfactory postoperative course.

Intra-abdominal testis with mature teratoma

Abstract Tumors in an undescended testis are rare in children. We report a mature teratoma arising in the intra-abdominal testis (IAT) of a 1-year-old boy. Preoperative laparoscopy revealed a right IAT near the inguinal ring. As the right testis exposed through the inguinal incision seemed to be a neoplastic mass, an orchidectomy was performed. Histologic examination disclosed a mature teratoma. This is a review of seven cases (including the present one) of a prepubertal tumor originating in an IAT. We speculate that the undescended testes did not cause the neoplasia, but were induced by it.

The protective and anti-inflammatory effects of glucagon-like peptide-2 in an experimental rat model of necrotizing enterocolitis.

Necrotizing enterocolitis (NEC) is a devastating gastrointestinal disease, that affects premature infants. Glucagon-like peptide-2 (GLP-2) is an intestinotrophic hormone and reduces the inflammation. We suspected that GLP-2 would have protective and anti-inflammatory effects in an experimental rat model of NEC. NEC was induced in newborn rats by enteral feeding with hyperosmolar formula, asphyxial stress and enteral administration of lipopolysaccharide (LPS). Rats were randomly divided into the following four groups: dam-fed, NEC, NEC+GLP-2(L) given 80 μg/kg/day of GLP-2, and NEC+GLP-2(H) given 800 μg/kg/day of GLP-2. GLP-2 was administered subcutaneously every 6 h before stress. All animals surviving beyond 96 h or any that developed signs of distress were euthanized. The clinical sickness score in the NEC+GLP-2(H) group was significantly lower than that in the NEC group. The NEC score and the survival rate in the NEC+GLP-2(H) group was significantly improved compared with those in the NEC and the NEC+GLP-2(L) groups. Villous height and crypt depth in both the GLP-2 treatment groups were significantly increased compared with those in the NEC group. There were no significant differences in the crypt cell proliferation indices among the groups. Ileal interstitial TNF-α and IL-6 level in the NEC+GLP-2(H) group was decreased to the same levels in the dam-fed group. High dose GLP-2 administration improved the incidence and survival rate for NEC. It also decreased mucosal inflammatory cytokine production. These results support a potential therapeutic role for GLP-2 in the treatment of NEC.

Ghrelin and glucagon-like peptide-2 increase immediately following massive small bowel resection

Children with short bowel syndrome face life-threatening complications. Therefore, there is an urgent need for a new therapy to induce effective adaptation of the remnant intestine. Adaptation occurs only during feeding. We focused on preprandial acyl ghrelin and des-acyl ghrelin, and postprandial glucagon-like peptide-2 (GLP-2), which are known to have active orexigenic and trophic actions. This study aims to clarify the secretion trends of these hormones after massive small bowel resection and to obtain basic data for developing a new treatment. Sixty-three growing male rats were used: 3 were designated as controls receiving no operation and 60 were randomized into the 80% small bowel resection (80% SBR) group and the transection and re-anastomosis group. Changes in body weight, food intake, and remnant intestine morphology were also assessed for 15 days after the operation. Acyl ghrelin and des-acyl ghrelin levels increased immediately, equivalently in both operation groups (P=0.09 and 0.70). Interestingly, in 80% SBR animals, des-acyl ghrelin peaked on day 1 and acyl ghrelin peaked on day 4 (P=0.0007 and P=0.049 vs controls). GLP-2 secretion was obvious in 80% SBR animals (P=2.25×10(-6)), which increased immediately and peaked on day 4 (P=0.009 vs. controls). Body weight and food intake in 80% SBR animals recovered to preoperative levels on day 4. Morphological adaptations were evident after day 4. Our results may suggest a management strategy to reinforce these physiological hormone secretion patterns in developing a new therapy for short bowel syndrome.

Long-term outcome of bowel function for 110 consecutive cases of Hirschsprung's disease: Comparison of the abdominal approach with transanal approach more than 30 years in a single institution – is the transanal approach truly beneficial for bowel function?

BACKGROUND We compared the long-term outcomes of the bowel function (BF) in Hirschsprungs disease (HD) patients who underwent transanal endorectal pull-through (TA) with those who underwent the Soave-Denda (SD) procedure. METHODS Patient data were collected from 1984 to 2015 from 110 HD patients who underwent definitive diagnosis and operation. The follow-up data were analyzed retrospectively. BF was evaluated according to the evacuation score (ES) of the Japan Society of Anorectal Malformation Study Group at 3, 5, 7, 9, and 11years of age. RESULTS The operative procedures performed were as follows: SD: 71 (64.5%), TA: 38 (34.5%), and Duhamel: 1 (1.0%). We compared SD with TA. The ES improved chronologically after both procedures, and patients achieved satisfactory results at least 10years after operation. There was no significant difference in the total ES at all ages. The incontinence and frequency of bowel movement scores of TA patients were significantly lower than those of SD patients at several points. CONCLUSION TA is simple, less invasive, and adaptive for neonates and small infants. However, regarding the bowel function, TA is not always superior to SD. The surgical technique of TA must be improved according to a detailed understanding of the anatomy. LEVEL OF EVIDENCE Retrospective study - level III.

Ghrelin improves intestinal mucosal atrophy during parenteral nutrition: An experimental study

BACKGROUND/PURPOSE Total parenteral nutrition (TPN) has been reported to be associated with mucosal atrophy of the small intestine. Ghrelin has hormonal, orexigenic, and metabolic activities. We investigated whether ghrelin improved intestinal mucosal atrophy using a TPN-supported rat model. METHODS Rats underwent jugular vein catheterization and were divided into four groups: TPN alone (TPN), TPN plus low-dose ghrelin (TPNLG), TPN plus high-dose ghrelin (TPNHG), and oral feeding with normal chow (OF). Ghrelin was administered continuously at dosages of 10 or 50 μg/kg/day. On day 6 rats were euthanized, and the small intestine was harvested and divided into the jejunum and ileum. Then the villus height (VH) and crypt depth (CD) were evaluated. RESULTS The jejunal and ileal VH and CD in the TPN group were significantly decreased compared with those in the OF group. TPNHG improved only VH of the jejunum. TPNLG improved VH and CD of the jejunum and CD of the ileum. The improvement of TPNLG was significantly stronger than that in CD of the jejunum and ileum. CONCLUSIONS TPN was more strongly associated with mucosal atrophy in the jejunum than in the ileum. Low-dose intravenous administration of ghrelin improved TPN-associated intestinal mucosal atrophy more effectively than high-dose administration.

Cervico-Mediastinal Bronchogenic Cyst Occurring in the Prenatal Period: Report of a Case

Abstract We experienced a case of cervico-mediastinal bronchogenic cyst in which a cervical cystic mass was detected by prenatal ultrasonography. On prenatal ultrasound, a unilocular, well-defined and hypoechoic mass was detected in the fetal neck. The baby was born by a normal vaginal delivery at 40 weeks of gestation, and had no respiratory distress. Radiological investigations demonstrated a cyst in the cervico-mediastinal region, which displaced the trachea to the left. At the age of 32 days, an elective resection was easily performed through a right inferior collar incision after first aspirating the contents of the cyst. Prenatal sonography showing abnormal findings is effective for identifying cysts in the perinatal period and allows for the timely resection of such cysts before respiratory distress occurs.