Impact of Total Parenteral Nutrition on Preoperative Management of Pediatric Living-Donor Liver Transplantation for Biliary Atresia Under 2 Years Old

BACKGROUND

Liver failure and gastrointestinal bleeding occur in the end-stage of biliary atresia (BA). Living-donor liver transplantation (LDLT) is a standard treatment in Japan. Our program actively provides pre-transplant total parenteral nutrition (TPN) for such patients, and here we report its efficiency and safety.

METHODS

Patients with BA for whom LDLT was indicated were identified. Those with a long-term external central venous catheter and TPN, longer than 4 weeks before LDLT, were analyzed. Ascites was controlled with diuretics. TPN indications, efficacy, and complications were assessed along with patient growth, biochemical markers, and gastrointestinal bleeding.

RESULTS

Fourteen patients were included in the study, of whom 8 were girls and 6 were boys. The median age at LDLT was 0.9 years. Body weight (BW) at TPN initiation averaged 6799 g, and the median serum total bilirubin was 9.5 mg per dL. The median catheterization duration was 54 days, and 1 patient received home TPN. Indications for TPN were gastrointestinal bleeding and/or massive esophageal varices in 4 patients and poor nutritional status in 10 patients. No complications were observed except for 1 catheter infection and 1 catheter occlusion. The median final body weight before LDLT was 7906 g. The mean rate of BW gain was significantly higher after TPN than before (149 vs 32 g/wk, respectively, P = .0002). Mean prothrombin time and levels of albumin, cholinesterase, and total bilirubin were not significantly different at the start and end of TPN.

CONCLUSIONS

Pre-transplant TPN was safe and effective for patients with end-stage BA.

Plasma Concentration of Antifungal Agent Micafungin for Pediatric Living Donor Liver Transplantation

BACKGROUND

Pediatric living-donor liver transplantation (LDLT) candidates often receive long-term antibiotic treatment. Micafungin has been used as an antifungal agent after LDLT, but the adequate dose after pediatric LDLT was unknown. Here, we report micafungin blood concentrations after pediatric LDLT and discuss its safety and adequate dosing.

METHODS

Pediatric patients with data on micafungin concentrations after LDLT were identified. Those with surgical complications were excluded. All patients received standard tacrolimus-based immunosuppression. A micafungin dose of 1 mg/kg was administered once daily for 10 days starting on postoperative day (POD) 1. The trough and peak micafungin blood concentrations were evaluated on PODs 1, 4, 7, and 10. Beta D glucan levels and liver function tests were assessed to determine micafungin effectiveness and safety.

RESULTS

Ten patients were enrolled, with a median age of 1.2 years. The median graft vs body weight ratio was 2.7%. The primary diseases were biliary atresia (n = 7), Alagille syndrome (n = 2), and progressive familial intrahepatic cholestasis type 2 (n = 1). Mean peak micafungin levels were 4.47, 6.27, 5.47, and 5.47 µg/mL on PODs 1, 4, 7, and 10, respectively. Mean trough levels were 2.03, 1.88, and 2.66 µg/mL on PODs 4, 7, and 10, respectively. The micafungin half-lives were 13.7, 14.7, and 14.0 hours on PODs 4, 7, and 10, respectively. Beta D glucan levels were 4.4 pg/mL and 3.7 pg/mL before and after transplantation, respectively, indicating no significant difference (P = .3). No clinical fungal infections were observed.

CONCLUSION

Micafungin administration is safe and effective after pediatric LDLT.

Balloon dilatation for congenital esophageal stenosis associated with esophageal atresia

PURPOSE

Congenital esophageal stenosis (CES) associated with esophageal atresia (EA) is rare, and no standard treatment has been established. We reviewed cases of EA-associated CES to assess the clinical characteristics and treatment outcomes, especially the feasibility of endoscopic dilatation.

METHODS

We retrospectively examined patients with EA-associated CES. We also compared treatment outcomes of EA-associated CES with those of EA patients without CES who developed postoperative anastomotic stricture.

RESULTS

Among 44 patients with EA, ten had CES (23%). Postoperative complications were not significantly different between EA patients with CES and those without CES but with anastomotic stricture. All CES patients underwent balloon dilatation as initial treatment. Eight of nine patients (89%) were successfully treated by dilatation only, and one patient underwent surgical resection. The median number of balloon dilatations for CES was five (2-17), which was higher than that for anastomotic stricture in patients without CES (p = 0.012). Esophageal perforation occurred in five patients with CES (5/9, 56%) after dilatation, but all perforations were successfully managed conservatively with an uneventful post-dilatation course.

CONCLUSIONS

Twenty-three percent of patients with EA had CES. Although balloon dilatation for EA-associated CES required multiple treatments and carried a risk of perforation, balloon dilatation showed an 89% success rate and all perforations could be managed conservatively.

Clinical Implications of Serum Mac-2 Binding Protein in Patients After Living Donor Liver Transplantation for Biliary Atresia

BACKGROUND

Patients who undergo pediatric living donor liver transplantation (LDLT) sometimes develop graft fibrosis. Recently, Mac-2 binding protein glycosylation-modified isomer (M2BPGi) was developed as a new marker of hepatic fibrosis progression. We performed this study to examine the relationship between serum M2BPGi levels and liver histologic findings in patients after LDLT for biliary atresia.

METHODS

Patients aged <19 years who underwent LDLT for biliary atresia at our institution and followed up for at least 1 year after LDLT were eligible. There were 56 patients in this study. Pathologic findings of the last available biopsy were assessed. Portal vein (PV) stenosis was confirmed with angiography. M2BPGi levels were compared with pathologic fibrosis scores and PV stenosis findings.

RESULTS

The mean age at transplant was 4.3 years. The mean observation period was 8.6 years. In terms of the degree of liver fibrosis, F0 was observed in 7 patients, F1 in 36, and F2 in 13. The median serum M2BPGi value was 0.8 cut-off index (COI) overall and 0.60 COI for F0, 0.74 COI for F1, and 1.07 COI for F2. The mean M2BPGi value in F2 was higher than that in F0 (P = .016) and F1 (P = .012). Mean serum M2BPGi values were 1.57 COI (0.29 COI) in patients with PV complications (n = 5) and 0.72 COI in patients without PV complications (n = 51) (P = .0001).

CONCLUSION

M2BPGi is a novel marker for liver fibrosis in patients after pediatric LDLT. It is especially useful for follow-up of pediatric patients after LDLT to support liver biopsy interpretation.

Regeneration Process of an Autologous Tissue-Engineered Trachea (aTET) in a Rat Patch Tracheoplasty Model

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.

Potential risks associated with laparoscopic gastrostomy in patients with the COL4A1 variant: Two case reports

The COL4A1 (collagen Type 4 alpha1) pathogenic variant is associated with porencephaly and schizencephaly and accounts for approximately 20% of these patients. This gene variant leads to systemic microvasculopathy, which manifests as brain, ocular, renal, and muscular disorders. However, only a few patients with surgical interventions have been reported and the potential surgical risks are unknown. Here, we present the cases of two female patients between 7 and 8 years of age who were diagnosed with the COL4A1 variant and underwent laparoscopy-assisted percutaneous endoscopic gastrostomy (LAPEG) for oral dysphagia. Their primary brain lesions were caused by porencephaly and paralysis, which are caused by multiple cerebral hemorrhages and infarctions, and both patients had refractory epileptic complications. Although LAPEG was successfully performed in both patients without any intraoperative complications, one patient developed alveolar hemorrhage postoperatively and required mechanical ventilation. Thus, careful perioperative management of patients with the COL4A1 variant is important.

Mean structure of the supercritical turbulent spiral in Taylor-Couette flow

The large-scale laminar/turbulent spiral patterns that appear in the linearly unstable regime of counter-rotating Taylor-Couette flow are investigated from a statistical perspective by means of direct numerical simulation. Unlike the vast majority of previous numerical studies, we analyse the flow in periodic parallelogram-annular domains, following a coordinate change that aligns one of the parallelogram sides with the spiral pattern. The domain size, shape and spatial resolution have been varied and the results compared with those in a sufficiently large computational orthogonal domain with natural axial and azimuthal periodicity. We find that a minimal parallelogram of the right tilt significantly reduces the computational cost without notably compromising the statistical properties of the supercritical turbulent spiral. Its mean structure, obtained from extremely long time integrations in a co-rotating reference frame using the method of slices, bears remarkable similarity with the turbulent stripes observed in plane Couette flow, the centrifugal instability playing only a secondary role. This article is part of the theme issue 'Taylor-Couette and related flows on the centennial of Taylor's seminal Philosophical transactions paper (Part 2)'.

Regenerative medicine: current research and perspective in pediatric surgery

The field of regenerative medicine, encompassing several disciplines including stem cell biology and tissue engineering, continues to advance with the accumulating research on cell manipulation technologies, gene therapy and new materials. Recent progress in preclinical and clinical studies may transcend the boundaries of regenerative medicine from laboratory research towards clinical reality. However, for the ultimate goal to construct bioengineered transplantable organs, a number of issues still need to be addressed. In particular, engineering of elaborate tissues and organs requires a fine combination of different relevant aspects; not only the repopulation of multiple cell phenotypes in an appropriate distribution but also the adjustment of the host environmental factors such as vascularisation, innervation and immunomodulation. The aim of this review article is to provide an overview of the recent discoveries and development in stem cells and tissue engineering, which are inseparably interconnected. The current status of research on tissue stem cells and bioengineering, and the possibilities for application in specific organs relevant to paediatric surgery have been specifically focused and outlined.

Ileocecal valve-sparing surgery for duplication cysts in the terminal ileum: two case reports and literature review

Background

Duplication cysts close to the ileocecal valve are usually treated with ileocecal resection. However, loss of the ileocecal valve will lead to problems, especially in infants. Mucosectomy of the cyst would be a better alternative that preserves the ileocecal valve. We report two cases of duplication cyst in the terminal ileum successfully treated with mucosectomy.

Case presentation

Case 1. A 3-month-old boy with bilious emesis and abdominal distention was referred to our hospital with a diagnosis of small bowel obstruction caused by an abdominal cyst. Computed tomography revealed a cystic mass compressing the terminal ileum and causing mechanical small bowel obstruction. His general condition deteriorated quickly; emergency laparotomy was performed. Although the small intestines were dilated and partially twisted, there was no necrosis. Following intestinal decompression, a cystic mass adjacent to the terminal ileum was confirmed on the mesenteric side. Cyst mucosectomy was performed to preserve the ileocecal valve. Case 2. A 5-month-old boy with sudden onset of hematochezia was referred to our hospital with a diagnosis of intussusception. Following unsuccessful contrast enemas, emergency surgery was performed. A cystic mass adjacent to the terminal ileum was confirmed; there was no intussusception. Cyst mucosectomy was performed. Both patients had an uneventful postoperative course.

Conclusions

Cyst mucosectomy, which preserves the ileocecal valve, is safe and effective for treating duplication cysts in the terminal ileum.

Tension-free thoracoscopic repair of congenital diaphragmatic hernia combined with a percutaneous extracorporeal closure technique: how to do it

PURPOSE

Thoracoscopic repair (TR) of congenital diaphragmatic hernia (CDH) is associated with a higher recurrence rate than the conventional open method. We evaluated the effectiveness of our strategy for quality improvement, named "tension-free TR of CDH".

METHODS

The subjects of this retrospective analysis were 11 consecutive patients with CDH who underwent TR at our hospital between 2017 and 2021. Tension-free TR of CDH included the proactive use of an oversized patch for dome-shaped reconstruction and gapless suturing. We developed a percutaneous extracorporeal closure technique for secure suturing using a commercially available needle.

RESULTS

Patch repair was performed in 8 (73%) patients and none required conversion to open surgery because of technical difficulties. Recurrence developed in one patient (9%), who underwent successful reoperation via TR. All patients had an uneventful postoperative course.

CONCLUSION

Tension-free TR combined with extracorporeal closure could reduce the difficulty of suturing and the risk of recurrence of CDH.

Laparoscopic Percutaneous Extraperitoneal Closure for Hydrocele of the Canal of Nuck in Children

Background: Hydrocele of the canal of Nuck (HCN) is a rare cause of inguinal swelling in women. The optimal surgical procedure for HCN in children remains unclear. To assess the safety and efficacy of laparoscopic percutaneous extraperitoneal closure (LPEC) for HCN in a pediatric population, a retrospective study was conducted. In addition, to clarify the pathogenesis of HCN, we assessed the morphological findings of the internal inguinal ring (IIR). Materials and Methods: We retrospectively analyzed 10 consecutive female patients with HCN who underwent LPEC at our hospital between January 2010 and May 2020. Age, operative time, and complications were recorded. Concerning the findings of the IIR, we classified the morphological features as follows: Type 1 (flat), Type 2 (narrow patent processus vaginalis [PPV] with a peritoneal veil), and Type 3 (widely opening PPV). Results: The median age of patients who underwent LPEC was 3 (1-12) years. Although 2 patients showed contralateral inguinal hernia (IH), there were no cases of ipsilateral IH. All patients showed ipsilateral PPV, and the morphological features of the IIR were mostly classified as Type 3 (70%). In total, 6 of 8 HCN cases without preoperatively diagnosed contralateral IH had contralateral PPV (75%), and all were closed by LPEC. All operations were accomplished laparoscopically, and the postoperative course was uncomplicated, with no recurrences observed during the study period. Conclusions: LPEC is a safe and simple surgical approach to repair the HCN in children with minimal complications.

Clinical implications of serum autotoxin in regular follow up after pediatric living donor liver transplantation for biliary atresia

BACKGROUND

Pediatric patients sometimes develop graft fibrosis after living donor liver transplant (LDLT). Autotaxin is a recently developed serum marker for hepatic fibrosis. We studied the relationship between serum autotaxin levels and histological findings in patients after LDLT for biliary atresia (BA).

METHODS

Information on patients aged <19 years who received LDLT for BA and were followed for at least 1 year after LDLT was gathered. Autotaxin levels were compared with pathological fibrosis scores.

RESULTS

The study included 52 patients, of whom 4 patients had no fibrosis (F0), 36 patients had F1 fibrosis, and 12 patients had F2. The median serum autotaxin level was 0.89 mg/L. In patients with portal vein (PV) complications such as stenosis or thrombosis (n = 7), the mean autotoxin level was 1.25 mg/L compared with 0.95 mg/L in patients without PV complications (p = 0.004). Among patients without PV complications, the mean autotaxin level was 0.90, 0.88, and 1.18 mg/L in F0, F1, and F2 fibrosis, respectively. The mean autotaxin was higher in F2 fibrosis than in F0 or F1 fibrosis (p<0.05). Autotoxin had a high area under the curve (0.86) with the cut-off level of 0.897 mg/L.

CONCLUSION

Serum autotaxin is a novel marker for liver fibrosis in patients after pediatric LDLT for BA.

TYPE OF STUDY

Study of Diagnostic Test.

LEVEL OF EVIDENCE

Level II.

Development of a porcine acellular bladder matrix for tissue-engineered bladder reconstruction

PURPOSE

Enterocystoplasty is adopted for patients requiring bladder augmentation, but significant long-term complications highlight need for alternatives. We established a protocol for creating a natural-derived bladder extracellular matrix (BEM) for developing tissue-engineered bladder, and investigated its structural and functional characteristics.

METHODS

Porcine bladders were de-cellularised with a dynamic detergent-enzymatic treatment using peristaltic infusion. Samples and fresh controls were evaluated using histological staining, ultrastructure (electron microscopy), collagen, glycosaminoglycans and DNA quantification and biomechanical testing. Compliance and angiogenic properties (Chicken chorioallantoic membrane [CAM] assay) were evaluated. T test compared stiffness and glycosaminoglycans, collagen and DNA quantity. p value of < 0.05 was regarded as significant.

RESULTS

Histological evaluation demonstrated absence of cells with preservation of tissue matrix architecture (collagen and elastin). DNA was 0.01 μg/mg, significantly reduced compared to fresh tissue 0.13 μg/mg (p < 0.01). BEM had increased tensile strength (0.259 ± 0.022 vs 0.116 ± 0.006, respectively, p < 0.0001) and stiffness (0.00075 ± 0.00016 vs 0.00726 ± 0.00216, p = 0.011). CAM assay showed significantly increased number of convergent allantoic vessels after 6 days compared to day 1 (p < 0.01). Urodynamic studies showed that BEM maintains or increases capacity and compliance.

CONCLUSION

Dynamic detergent-enzymatic treatment produces a BEM which retains structural characteristics, increases strength and stiffness and is more compliant than native tissue. Furthermore, BEM shows angiogenic potential. These data suggest the use of BEM for development of tissue-engineered bladder for patients requiring bladder augmentation.

Factors Associated With Adverse Outcomes Following Duodenal Atresia Surgery in Neonates: A Retrospective Study

Objectives

There is limited evidence on the infants' postoperative complications who have undergone surgical repair of duodenal atresia and stenosis. This study aimed to identify the factors associated with poor surgical outcomes after the initial repair.

Methods

We retrospectively reviewed the data of 82 patients who underwent surgery for duodenal atresia and stenosis between January 1994 and December 2013 at our institution. Gestational age, birth weight, fetal growth, and other associated anomalies were recorded. Multivariate regression analyses were used to identify the factors associated with surgical outcomes, including postoperative complications and time to full oral intake.

Results

The median gestational age was 37.6 weeks, with 30 (37%) preterm (<37 weeks) and 11 (13%) early preterm (<34 weeks) infants. The median birth weight was 2531 g, with 27 (33%) patients < 2000 g and 10 (12%) patients < 1500 g. Postoperative surgical complications were identified in 18 (22%) cases, of which 12 (15%) required additional operations. Multivariate regression analysis revealed that a combination of very low birth weight (<1500 g) and early preterm was significantly associated with both surgical and non-surgical postoperative complications (p = 0.0028 and 0.021, respectively) and a prolonged time to full oral intake postoperatively (p = 0.013).

Conclusion

Very low birth weight and early preterm were significantly associated with postoperative complications and a prolonged time to full oral intake.

A Retransplant Case for Hepatopulmonary Syndrome Without Liver Cirrhosis or Portosystemic Shunt After Living-Donor Liver Transplantation: A Case Report

Hepatopulmonary syndrome (HPS) is a disease of gas exchange caused by intrapulmonary shunting secondary to liver disease-associated intrapulmonary vascular dilation. HPS is characterized by the triad of cirrhosis, chronic liver disease, or portosystemic shunting (PSS); arterial hypoxemia; and intrapulmonary arteriovenous shunting in the absence of a primary cardiopulmonary anomaly. We encountered a rare case of HPS without liver disease or PSS. The patient was an 8-year-old girl who underwent living donor liver transplantation (LDLT) shortly after developing fulminant hepatitis at 11 months of her age. Eight years after LDLT, hypoxemia and shortness of breath developed. The shunt ratio on ^99mTc-macroaggregated albumin (MAA) lung perfusion scintigraphy (^99mTc-MAA lung scan) was 32%. The patient had no cardiopulmonary disease, so we diagnosed her illness as HPS. We did not find cirrhosis, chronic liver disease, or PSS as a cause of HPS. We thought the graft was the cause of HPS. A second transplantation was planned. One year after the diagnosis of HPS, the shunt ratio on ^99mTc-MAA lung scan worsened to 42%, digital clubbing appeared, and hypoxemia was worsening. Thus, we performed a second LDLT. After LDLT the shunt ratio on ^99mTc-MAA lung scan normalized (6%) and cyanosis resolved. We determined that the graft was the cause of HPS; the typical causes of HPS were not clearly revealed in the histologic examination of the second liver explant. Acute rejection occurred twice after LDLT, so we speculated that HPS occurred because the graft became stressed over the long term.

Impact of serum autotaxin level correlating with histological findings in biliary atresia

PURPOSE

Portoenterostomy is the standard treatment for biliary atresia (BA) that reduces jaundice in two thirds of cases. However, progressive liver fibrosis is common, leading to cirrhosis in most patients. Autotaxin is a new marker for the progression of hepatic fibrosis. We examined the relationship between serum autotaxin levels and liver histological findings in patients with BA.

METHODS

BA patients with native livers were identified in our hospital. Patients underwent protocol liver biopsies every 1 to 5 years, and liver fibrosis was evaluated based on the METAVIR score. Serum autotaxin levels were compared with the last available pathological findings.

RESULTS

Thirty-five patients were included and the median age was 10.6 years. Serum autotaxin levels was median 1.6 mg/L. The mean autotaxin level was 1.08 mg/L in F0, 1.07 mg/L in F1, 0.95 mg/L in F2, 2.17 mg/L in F3, and 2.50 mg/L in F4; it was significantly higher in F4 than in F0-F2 (P<0.0024). For predicting cirrhosis (F4) and advanced liver fibrosis (≥F3), autotaxin had the almost same areas under the curve (AUCs 0.78 and 0.90, respectively) as well as M2BPGi.

CONCLUSION

Autotaxin levels could be used to evaluate the status of native liver fibrosis.

Esophageal atresia with right aortic arch: An experience of thoracoscopic repair through left thorax

Right aortic arch (RAA) is one of congenital cardiovascular anomalies associated with esophageal atresia (EA). The surgical treatment for EA with RAA is still challenging. Although most pediatric surgeons are familiar with the right-sided approach, the division of the tracheoesophageal fistula and the anastomosis of the esophagus through right thorax are often difficult in cases of RAA. There are a few reports on thoracoscopic repair for EA with RAA. We report a case of EA with RAA treated by left-sided thoracoscopic approach. With left-sided thoracoscopic approach, identification and anastomosis of the esophagus could be safely performed without obstruction by the right-sided descending aorta. There was no leakage or stricture. Thoracoscopic repair of EA with RAA through the left thorax is feasible and safe without obstruction by the right-sided descending aorta.

Thoracoscopic Costal Cartilage Excision Combined with the Nuss Procedure for Patients with Asymmetrical Pectus Excavatum

Background and Aims: We performed thoracoscopic costal cartilage excision (TCCE) combined with the Nuss procedure to correct asymmetrical pectus excavatum (PE). We reviewed the efficacy of combined TCCE and Nuss procedure for asymmetric PE. Patients and Methods: Overall, 8 patients with asymmetrical PE underwent TCCE with the Nuss procedure. The Haller index, asymmetry index, and angle of sternal rotation were calculated using preoperative computed tomography. The procedure was performed using bilateral 2.5-cm incisions at the same level of the deepest chest wall depression. The most depressed three to four costal cartilages were partially resected through a right mini-thoracotomy. Subsequently, one or two titanium bars were implanted and secured with stabilizers. The cosmetic outcome was evaluated on the following four ratings: excellent, good, fair, and failure ( = recurrence). Results: The median age at surgery was 14.5 years (8-20 years). The number of bars was one in 3 cases and two in 5 cases. The preoperative Haller index, asymmetry index, and angle of sternal rotation were 4.3 (3.5-5.9), 1.15 (1.04-1.26), and 21.5° (15°-31°), respectively; 2 patients had scoliosis before the Nuss procedure. Complications included surgical site infection and hemothorax. Median follow-up time was 25.5 months (3-63). Bars were removed in 3 patients, 3 years postoperatively. Cosmetic results were excellent, 4; good, 2; fair, 1; failure, 1. Both patients with scoliosis had poor outcomes (fair, 1; failure, 1). Conclusions: Combined TCCE with Nuss procedure is considered safe and effective for patients with asymmetrical PE. Careful long-term follow-up is required, especially in cases with scoliosis.

Development of matured hiPSCs-derived 3D cardiac tissue using ERR gamma agonist and mechanical stress and application for Hypertrophic Cardiomyopathy (HCM) model

Introduction

Tissue engineering using human induced pluripotent stem cells-derived cardiomyocytes (hiPSCs-CMs) is one of the potential tools to replicate human heart in vitro. Although there are many publications on 3 dimensional (3D) heart tissues (1), these tissues show fetal like phenotypes. For that reason, several maturation methods such as electrical stimulation and mechanical stress have been investigated (2, 3). However, these methods have been inadequate in differentiating fetal like phenotype tissue from adult tissues. Previously, we identified a novel compound, T112, which induced hiPSCs-CMs maturation from approximately 9,000 compounds using Troponin I1-EmGFP and Troponin I3-mCherry double reporter hiPSCs-CMs. This compound enhanced morphological and metabolic maturation of hiPSCs-CMs via estrogen-rerated receptor gamma activation

Purpose

We hypothesized that our novel compound, T112, in combination with mechanical stress could result in further maturation of 3D heart tissue. Therefore, our specific aim is to develop a novel maturation method applicable to genetic disease model of HCM using 3D heart tissue combined with T112.

Methods

We constructed 3D heart tissue mixed with fibroblast and double reporter hiPSCs-CMs by the hydrogel methods using Flex cell system®. We added T112 with or without mechanical stretching to 3D tissue from 7 to 15 days after 3D heart tissue was constructed. Then we measured maturation related phenotype such as sarcomere gene expression, mitochondrial DNA content and cell size.

Results

Similar to hiPSCs-CM, the addition of T112 to the constructed 3D heart tissue significantly increased TNNI3 mRNA compared to that of DMSO. Furthermore, T112 treated 3D heart tissue showed increased cell size and oblong shape. Next, in order to promote more maturation of 3D heart tissue, we performed mechanical stretching with the addition of T112. The combination of T112 with mechanical stretching showed higher expression of mCherry, a reporter protein for TNNI3 expression, and higher isotropy of sarcomere alignment in 3D heart tissue than that with the static condition. Furthermore, 3D heart tissue in the treatment of T112 with or without mechanical stretching showed higher mitochondrial DNA content compared to the respective DMSO controls. Interestingly, we applied this combination method to hiPSCs carrying MYH7 R719Q mutation which is known to cause hypertrophic cardiomyopathy, and the 3D heart tissue composed of cardiomyocytes derived from mutant iPSCs demonstrated increased sarcomere disarray compared to isogenic wild-type 3D heart tissue.

Conclusion

These results suggest that the combination of T112 and mechanical stretching promotes metabolic and structural maturation of 3D heart tissue and would be useful for creating a HCM disease model.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): T-CiRA project, Takeda Pharmaceutical Company Limited

Does the "Endoscopic Surgical Skill Qualification System" Reduce Serious Intraoperative Complications in the Field of Pediatric Surgery?

Background: The Japanese endoscopic surgical skill qualification system (ESSQS) in pediatric surgery was started 10 years ago to encourage safe and appropriate pediatric minimally invasive procedures and avoid severe complications. The present study investigated the impact of the ESSQS on the incidence of serious complications in the field of pediatric endoscopic surgery. Materials and Methods: We sent a questionnaire to institutes belonging to the Japanese Pediatric Endoscopic Surgery Group. Institutes were divided into two groups: institutes with (Group A) or without (Group B) ESSQS-qualified pediatric surgeons at any point in the last 10 years. Intraoperative complications (grade 3 and 4 under the Classification of Intraoperative Complications [CLASSIC] classification), postoperative complications (grade ≥IIIb under the Clavien/Dindo classification), and the number and rate of endoscopic procedures and complications of advanced and common procedures were compared between the two groups. This study is an exempt survey since no patient identifier has been collected. Results: We collected answers from 46 of 102 institutes (response rate: 45%) (Group A: 18 institutes, Group B: 28 institutes). Intra/postoperative complications were significantly more frequent in Group A than in Group B (P = .02 and P < .001, respectively). Endoscopic operations accounted for a larger proportion of advanced and common surgeries in Group A than in Group B, and the rate of postoperative complications of advanced procedures was significantly higher in Group A than in Group B (P = .012). Conclusion: While endoscopic surgery was performed more frequently in Group A than in Group B, the incidence of intra/postoperative serious complications was significantly higher in Group A. The current Japanese ESSQS was unable to markedly reduce the rate of serious complications.

Laparoscopy-Assisted Transscrotal Orchidopexy for Palpable Undescended Testis: Initial Results

Background: Undescended testis (UDT) is one of the most common congenital genital malformations in boys. However, orchidopexy carries a risk of injuring the testicular vessels and vas deferens. We therefore developed a novel approach to manage palpable UDT. Materials and Methods: We analyzed the medical records of patients who underwent orchidopexy at our institute between January 2017 and April 2020. This study was approved by the Institutional Review Board of our hospital. The age, body weight, laterality, testicular position, length of operation, and complications were investigated. The patients were classified into two groups depending on the surgery received: laparoscopy-assisted transscrotal orchidopexy (LATO) or conventional inguinal orchidopexy (CO). In brief, LATO involves preceding laparoscopic closure of the patent processus vaginalis (PPV) followed by transscrotal orchidopexy. Dissection of the PPV from the testicular vessels and vas deferens was minimized through this procedure. The chi-squared test and t-test were used to analyze the significance of the data. Results: Among a total of 49 patients, 24 (33 testes) underwent LATO, and 25 (30 testes) underwent CO. There was no significant difference in patients' age, body weight, or laterality. The length of operation was similar between the groups in both unilateral and bilateral cases. The contralateral PPV was confirmed in 80% of unilateral cases of LATO (12/15). No complications, including testicular atrophy and postoperative ascent, were noted in either group. Conclusions: There were no significant differences between the groups in the surgical results. However, the confirmation and ligation of the PPV were easier in LATO, and peeling of the testicular vessels and vas deferens was minimized. LATO may be safe and effective for managing palpable UDT.

Serum Trough Concentration and Effects of Mycophenolate Mofetil Based on Pathologic Findings in Infants After Liver Transplantation

OBJECTIVES

Mycophenolate mofetil (MMF) is mainly used in conjunction with calcineurin inhibitors as an additional immunosuppressive for renal sparing after liver transplantation. However, few reports about MMF use in infants after living donor liver transplantation (LDLT) are available. The purpose of this study was to examine the efficacy and safety of MMF in infants.

METHODS

This study enrolled infants younger than 1 year of age who received LDLT at our institution. Patients received oral MMF twice daily. The initial dose was 40 to 50 mg/kg/d, which was increased to a target mycophenolic acid (MPA) trough level of 2 mg/L. Body weight, height, MMF dose, MPA trough level, acute cellular rejection (ACR) episodes, pathologic findings, and adverse effects were analyzed. Allograft fibrosis was graded using the Meta-analysis of Histological Data in Viral Hepatitis score.

RESULTS

Patients received MMF for refractory ACR (n = 2), fulminant hepatitis (n = 2), and pre-existing antibodies (n = 1). Original diseases were biliary atresia (n = 3) and fulminant hepatitis (n = 2). Mean age at transplant was 8 months (range 3-10 months). The last available mean trough level was 2.7 mg/L. The mean dose was 66 mg/kg/d or 1429 mg/m²/d at the time of the last available through level. The regression line for MMF dose and MPA trough level was y = 1.8 × 10^-3x. The correlation coefficient was 0.65. All allografts showed F1 to F2 fibrosis. Two patients discontinued MMF because of infection and bone marrow suppression, respectively. Two patients converted to everolimus. One patient continued on MMF.

CONCLUSIONS

After LDLT, infants require a higher MMF dose than older patients based on trough levels, but allograft fibrosis can progress.

Beta-D-Glucan Levels With Use of an Anti-adhesion Barrier Film in Pediatric Living Donor Liver Transplantation

INTRODUCTION

Serum beta-D-glucan (BDG) levels may increase with anti-adhesion barrier film (ABF) use during pediatric living donor liver transplantation (LDLT). It may affect detection of fungal infections after LDLT. We evaluate BDG levels after pediatric LDLT.

METHODS

Pediatric patients who received an ABF during LDLT were included. Patients who may have had fungal infections prior to LDLT were excluded. One sheet of ABF was placed in the peritoneum during abdominal closure. Serum BDG levels before transplantation and on postoperative days (PODs) 1, 4, 7, 14, 21, and 28 and peritoneal fluid BDG levels on PODs 1 and 7 were measured.

RESULTS

Sixteen patients received an ABF during LDLT. Median age at transplant was 1.9 years (range, 6-11 years). Median body weight was 12.6 kg (range, 6.8-39 kg). Indications for LDLT were biliary atresia (n = 10) and other (n = 5). Prior to transplantation, the mean serum BDG level was 3.8 pg/mL. Mean Serum BDG levels were 18.1, 38.3, 5.3, 3.8, 3.3, and 3.3 pg/mL on PODs 1, 4, 7, 14, 21, and 28, respectively. Mean peritoneal fluid BDG levels were 485.9 and 240.4 pg/mL on PODs 1 and 7, respectively. No clinical fungal infections were observed.

CONCLUSIONS

BDG levels were high in serum and peritoneal fluid after pediatric LDLT. Serum BDG levels normalized after POD 7. Careful interpretation of BDG levels until POD 7 is needed when an ABF has been used.

Safety and Efficacy of Everolimus Rescue Treatment After Pediatric Living Donor Liver Transplantation

PURPOSE

Everolimus (EVR) is a derivative of sirolimus with a similar mechanism of action. The safety and efficacy of EVR after pediatric living donor liver transplantation (LDLT) are currently unknown. The purpose of this study was to examine the safety and efficacy of EVR as rescue therapy after pediatric LDLT.

METHODS

This study included patients younger than 19 years of age who received EVR after LDLT at our institution. EVR was administered as rescue treatment in addition to tacrolimus. In 21 patients, EVR dose, trough level, outcomes, and adverse effects were assessed.

RESULTS

Original diseases of patients consisted of biliary atresia (n = 11), Alagille syndrome (n = 3), fulminant hepatitis (n = 3), hepatoblastoma (n = 2), and other (n = 2). Mean age at transplant was 2.0 years (range 0.6-6.2 years). Mean age at initial EVR administration was 8.0 years (range 0.9-18.9 years). Indications for EVR use were graft fibrosis (n = 8), refractory acute cellular rejection (n = 5), renal sparing (n = 4), hepatoblastoma (n = 2), and chronic rejection (CR) (n = 2). Mean duration of administration was 17.1 months (range 2.1-60.4 months). Mean dose was 0.5 mg/m² twice daily. Mean EVR trough level was 2.5 ng/mL (range 1.5-5.0 ng/mL). Liver function improved and fibrosis did not progress in all patients with CR. However, 14 patients (67%) experienced adverse effects that required EVR dose reduction or discontinuation.

CONCLUSION

EVR is tolerable for pediatric patients after LDLT with dose adjustment. EVR had a certain effect to relieve progression on CR. Further follow-up is required.

One Year of Preemptive Valganciclovir Administration in Children After Liver Transplantation

OBJECTIVES

Valganciclovir (VGCV) is used as prophylaxis against cytomegalovirus (CMV) infection after pediatric living donor liver transplantation (LDLT). The purpose of this study was to examine the efficacy of 1 year of preemptive VGCV administration compared with a shorter administration after pediatric LDLT.

METHODS

VGCV was administered to 56 children who underwent LDLT. CMV and Epstein-Barr virus (EBV) antibody status, pp65 antigenemia, and other laboratory data were assessed at 1 year after LDLT. Patients were divided into the 1-year group (n = 32) (patients who had 1 year of VGCV administration) and the <1-year group (n = 24) (patients who had less than 1 year of VGCV administration).

RESULTS

Study participants consisted of 34 females and 22 males, with a mean age of 4.2 years at transplant. Regarding pretransplant donor (D)/recipient (R) CMV antibody status, 13 were D positive (+)/R negative (-), 27 were D+/R+, 8 were D-/R+, and 8 were D-/R-. For EBV, 22 were D+/R+, 32 were D+/R-, and 2 were D-/R-. In the 1-year group, only 2 patients (6.5%) developed CMV infection, whereas 8 patients (33.3%) developed CMV infection in the <1-year group. The CMV pp65 antigenemia assay was positive in 2 patients. CMV IgM was positive in 7 patients. One year of preemptive VGCV administration was associated with a lower incidence of CMV infection (P = .008), but not EBV infection. No adverse effects were observed.

CONCLUSIONS

One year of preemptive VGCV administration after LDLT is safe and suppresses CMV infection. It was useful after pediatric LDLT.

Whole rat stomach decellularisation using a detergent-enzymatic protocol

BACKGROUND

Conditions leading to reduced gastric volume are difficult to manage and are associated to poor quality-of-life. Stomach augmentation using a tissue-engineered stomach is a potential solution to restore adequate physiology and food reservoir. Aim of this study was to evaluate the decellularisation of whole rat stomach using a detergent-enzymatic protocol.

METHODS

Stomachs harvested from rats were decellularised through luminal and vascular cannulation using 24-h detergent-enzymatic treatment and completely characterized by appropriate staining, DNA and Extracellular matrix -component quantifications.

RESULTS

The detergent-enzymatic protocol allows a complete decellularisation of the gastric tissue, with a complete removal of the DNA with two cycles as confirmed by both quantifications and histological analysis. Extracellular matrix components, collagen, fibronectin, laminin and elastin, were optimally preserved by the treatment, while glycosaminoglycans were reduced.

CONCLUSION

Gastric tissue can be efficiently decellularised. Scaffolds retained original structure and important components that could enhance integration with other tissues for in vivo transplant. The use of naturally derived material could be potentially considered for the treatment of both congenital and acquired conditions.

Anticoagulant Activity in Cell Homogenate of Adult T Cell Leukemia

The hemostatic abnormality in 18 patients with adult T cell leukemia (ATL) was studied. Activated partial thromboplastin time (APTT) was slightly prolonged and prekallikrein activity was markedly low in these patients. The leukemic cell homogenate from these patients prolonged the recalcification time (RCT) of normal plasma; homogenates containing more than 3 ×103 cells/μi prolonged it, although a lower cell concentration shortened it. The crude anticoagulant fraction from the gel filtration, with a molecular weight of about 34,000, prolonged RCT. The crude anticoagulant did not affect prothrombin time (PT), thrombin activity or activated X activity at any concentration, but prolonged the contact activation test, inhibited the activation of prekallikrein and prolonged RCT of Fletcher trait, Fitzgerald trait and F XII deficient plasma. These effects of ATL cell homo-genate were stronger on platelet poor plasma than on platelet rich plasma. Although ATL cells had low procoagulant activity, increase of leukemic cells made anticoagulant activity predominant, might be the cause of hemostatic abnormality or amplify the bleeding tendency in patients with ATL.

The relationship between free-stream coherent structures and near-wall streaks at high Reynolds numbers

The present work is based on our recent discovery of a new class of exact coherent structures generated near the edge of quite general boundary layer flows. The structures are referred to as free-stream coherent structures and were found using a large Reynolds number asymptotic approach to describe equilibrium solutions of the Navier-Stokes equations. In this paper, first we present results for a new family of free-stream coherent structures existing at relatively large wavenumbers. The new results are consistent with our earlier theoretical result that such structures can generate larger amplitude wall streaks if and only if the local spanwise wavenumber is sufficiently small. In a Blasius boundary layer, the local wavenumber increases in the streamwise direction so the wall streaks can typically exist only over a finite interval. However, here it is shown that they can interact with wall curvature to produce exponentially growing Görtler vortices through the receptivity process by a novel nonparallel mechanism. The theoretical predictions found are confirmed by a hybrid numerical approach. In contrast with previous receptivity investigations, it is shown that the amplitude of the induced vortex is larger than the structures in the free-stream which generate it.This article is part of the themed issue 'Toward the development of high-fidelity models of wall turbulence at large Reynolds number'.

HLA-G1, but Not HLA-G3, Suppresses Human Monocyte/Macrophage-mediated Swine Endothelial Cell Lysis

The inhibitory function of HLA-G1, a class Ib molecule, on monocyte/macrophage-mediated cytotoxicity was examined. The expression of inhibitory receptors that interact with HLA-G, immunoglobulin-like transcript 2 (ILT2), ILT4, and KIR2DL4 (CD158d) on in vitro-generated macrophages obtained from peripheral blood mononuclear cells and the phorbol 12-myristate 13-acetate (PMA)-activated THP-1 cells were examined by flow cytometry. cDNAs of HLA-G1, HLA-G3, HLA-E, and human β2-microglobulin were prepared, transfected into pig endothelial cells (PECs), and macrophage- and the THP-1 cell-mediated PEC cytolysis was then assessed. In vitro-generated macrophages expressed not only ILT2 and ILT4 but CD158d as well. The transgenic HLA-G1 on PEC indicated a significant suppression in macrophage-mediated cytotoxicity, which was equivalent to that of transgenic HLA-E. HLA-G1 was clearly expressed on the cell surface of PEC, whereas the levels of HLA-G3 were much lower and remained in the intracellular space. On the other hand, the PMA-activated THP-1 cell was less expressed these inhibitory molecules than in vitro-generated macrophages. Therefore, the HLA-G1 on PECs showed a significant but relatively smaller suppression to THP-1 cell-mediated cytotoxicity compared to in vitro-generated macrophages. These results indicate that by generating HLA-G1, but not HLA-G3, transgenic pigs can protect porcine grafts from monocyte/macrophage-mediated cytotoxicity.

Studies of Pig Complement: Measurement of Pig CH50, ACH50, and Components

BACKGROUND

On the basis of a comparison of the hemolytic complement titer in pigs with that in humans, the complement system of pigs was investigated. The response of innate immunity, such as the natural antibodies, against humans was also examined.

METHODS

Hemolytic complement activity of pig serum was measured with the use of a microtitration technique. CH50 was determined according to the method of Mayer. ACH50 was assayed according to the methods of Platts-Milles and Ishizaka. Hemolytic activities of C1, C4, C2, C3, C5, C8, and C9 were estimated through the use of intermediate cells and reagents, as described previously. In addition, the pig natural anti-human antibody was studied with the use of human peripheral blood mononuclear cells (PBMCs). Human PBMCs were stained with 5% pig serum, followed by staining with fluorescein isothiocyanate-labeled goat anti-pig IgG and IgM. The resulting stained cells were quantified by use of a FACScalibur system. The alternative pathway of pig complement was also measured with the use of human erythrocytes and normal pooled pig serum with or without Mg(++)EGTA.

RESULTS

Both the CH50 and ACH50 titers were lower than those of humans. Concerning the components, except for C3, each component, that is, C1, C4, C2, C5, C8, and C9, was also lower than that of humans, based on measured values for human complement components. Pig serum clearly contains natural antibodies, IgG and IgM, to human PBMCs. The alternative pathway of pig complement reacted with human erythrocytes.

CONCLUSIONS

As a whole, pig innate immunity, the complement system and natural antibody, recognizes the surfaces of human cells.

'PrP systemic deposition disease': clinical and pathological characteristics of novel familial prion disease with 2-bp deletion in codon 178

BACKGROUND AND PURPOSE

A novel TYPE of prion disease associated mainly with autonomic-sensory polyneuropathy was reported by us previously.

METHODS

Here the autopsy pathology for patient 1 (the sister) and the clinical characteristics of her younger brother (patient 2) are newly reported. Polymerase chain reaction based restriction fragment length polymorphism analysis of the prion protein gene (PRNP) was performed on both patients and their father (normal control).

RESULTS

Polymerase chain reaction based restriction fragment length polymorphism analysis revealed a 2-bp deletion (CT) in codon 178 that causes an additional variable 25 amino acids at the C terminal, from the mutation site to the premature stop codon at codon 203, in both patients 1 and 2 but not in their father. The autopsy of patient 1 showed remarkable prion protein (PrP) deposits in the sympathetic ganglion and peripheral nerves, correlated to her severe autonomic sensory failure. PrP deposits were also found in the central nervous system and peripheral organs such as the heart, lung, stomach, jejunum, ileum, colon, urinary bladder and adrenal gland. The symptoms and biopsy findings of patient 2 were nearly the same as those reported previously for patient 1. His cognitive function was well preserved, but autonomic functions were severely impaired. His biopsied samples showed PrP deposits in the sural nerve and nerve plexuses of the stomach and colon.

CONCLUSION

The present unique 2-bp deletion (CT) in codon 178 induced a 'PrP systemic deposition disease' such as pan-autonomic failure, sensory neuropathy and mild cognitive impairment with a specific pathology.

Human HLA-Ev (147) Expression in Transgenic Animals

BACKGROUND

In our previous study, we reported on the development of substituting S147C for HLA-E as a useful gene tool for xenotransplantation. In this study we exchanged the codon of HLA-Ev (147), checked its function, and established a line of transgenic mice.

METHODS

A new construct, a codon exchanging human HLA-Ev (147) + IRES + human beta 2-microgloblin, was established. The construct was subcloned into pCXN2 (the chick beta-actin promoter and cytomegalovirus enhancer) vector. Natural killer cell- and macrophage-mediated cytotoxicities were performed using the established the pig endothelial cell (PEC) line with the new gene. Transgenic mice with it were next produced using a micro-injection method.

RESULTS

The expression of the molecule on PECs was confirmed by the transfection of the plasmid. The established molecules on PECs functioned well in regulating natural killer cell-mediated cytotoxicity and macrophage-mediated cytotoxicity. We have also successfully generated several lines of transgenic mice with this plasmid. The expression of HLA-Ev (147) in each mouse organ was confirmed by assessing the mRNA. The chick beta-actin promoter and cytomegalovirus enhancer resulted in a relatively broad expression of the gene in each organ, and a strong expression in the cases of the heart and lung.

CONCLUSION

A synthetic HLA-Ev (147) gene with a codon usage optimized to a mammalian system represents a critical factor in the development of transgenic animals for xenotransplantation.

Disseminated Metastatic Tissue Calcification After Orthotopic Liver Transplantation: A Case Report

BACKGROUND

Hypercalcemia has been observed in patients after liver transplantation. However, it is rare that the hypercalcemia induced disseminated tissue calcification and heart failure.

CASE REPORT

We report a rare case of heart failure caused by disseminated metastatic tissue calcification that involved extensive progressive myocardial calcification after liver transplantation. A 20-year-old man with end-stage liver disease due to biliary atresia underwent ABO-incompatible living donor liver transplantation. After successful transplantation, he suffered from antibody-mediated rejection. Subsequently, ABO-matched cadaveric liver retransplantation was successfully performed. Hypercalcemia developed gradually following the second transplantation. His serum calcium level increased to 18.3 mg/dL with sudden onset of ventricular tachycardia. Although he was resuscitated with a cardiopulmonary support device, he died of heart and liver failure. Histopathologic examination revealed systemic disseminated metastatic tissue calcification, including massive myocardial calcification.

CONCLUSION

Progressive worsening of hypercalcemia resulted in disseminated metastatic tissue calcification and massive metastatic myocardial calcification, which led to heart failure after liver transplantation. Because hypercalcemia after liver transplantation can cause fatal tissue calcification, early intervention for hypercalcemia should be considered.

Cognitive and affective functions in Alzheimer's disease patients with metabolic syndrome

BACKGROUND AND PURPOSE

The influence of metabolic syndrome (MetS) on cognitive and affective functions in patients with Alzheimer's disease (AD) was examined.

METHODS

A total of 570 AD patients were divided into two subgroups depending on waist circumference (WC) (normal versus achieving Japanese diagnostic criteria of MetS). Afterwards, the AD control subgroup was defined as those normal WC patients with no vascular risk factors (VRFs). The AD with MetS (AD-MetS) subgroup was defined as the MetS WC group who had two or more VRFs to qualify as having MetS. Cognitive and affective functions, insulin resistance, vascular endothelial function and white matter changes between AD-MetS and AD controls were compared.

RESULTS

Scores on the Mini-Mental State Examination, Hasegawa Dementia Score-Revised, Frontal Assessment Battery and Montreal Cognitive Assessment were worse in the AD-MetS group than in AD controls, but the difference was not significant. Some analyses were conducted twice, once including all patients and once including only late-elderly patients. Scores on the Geriatric Depression Scale were found to be significantly higher for AD-MetS than for AD controls (all ages, late-elderly), as were those for apathy (late-elderly). Furthermore, both the homeostasis model assessment of insulin resistance and reactive hyperemia index scores were significantly worse in AD-MetS than in AD controls, whilst white matter changes showed a tendency to be worse.

CONCLUSIONS

Greater cognitive and affective decline occurs in patients with AD-MetS than in those without. Further, insulin resistance and vascular endothelial dysfunction are strongly correlated with AD-MetS before pathological white matter changes can be observed.

Pressure-dependent magnetization and magnetoresistivity studies on tetragonal FeS (mackinawite): revealing its intrinsic metallic character

The transport and magnetic properties of the tetragonal Fe[Formula: see text]S were investigated using magnetoresistivity and magnetization within [Formula: see text] K, [Formula: see text] 70 kOe and [Formula: see text] 3.0 GPa. In addition, room-temperature x-ray diffraction and photoelectron spectroscopy were also applied. In contrast to previously reported nonmetallic character, Fe[Formula: see text]S is intrinsically metallic but due to a presence of a weak localization such metallic character is not exhibited below room temperature. An applied pressure reduces strongly this additional resistive contribution and as such enhances the temperature range of the metallic character which, for ∼3 GPa, is evident down to 75 K. The absence of superconductivity as well as the mechanism behind the weak localization will be discussed.

Canonical exact coherent structures embedded in high Reynolds number flows

The applications and implications of two recently addressed asymptotic descriptions of exact coherent structures in shear flows are discussed. The first type of asymptotic framework to be discussed was introduced in a series of papers by Hall & Smith in the 1990s and was referred to as vortex-wave interaction theory (VWI). New results are given here for the canonical VWI problem in an infinite region; the results confirm and extend the results for the infinite problem inferred the recent VWI computation of plane Couette flow. The results given define for the first time exact coherent structures in unbounded flows. The second type of canonical structure described here is that recently found for asymptomatic suction boundary layer and corresponds to freestream coherent structures (FCS), in boundary layer flows. Here, it is shown that the FCS can also occur in flows such as Burgers vortex sheet. It is concluded that both canonical problems can be locally embedded in general shear flows and thus have widespread applicability.

Characteristic RNA foci of the abnormal hexanucleotide GGCCUG repeat expansion in spinocerebellar ataxia type 36 (Asidan)

BACKGROUND AND PURPOSE

Spinocerebellar ataxia type 36 (SCA36), also called Asidan, is an autosomal-dominant neurodegenerative disorder identified as a hexanucleotide GGCCTG repeat expansion in the first intron 1 of the NOP56 gene. In the present study, for the first time an autopsy sample from an Asidan patient was examined and cytoplasmic inclusions and (GGCCUG)n repeat RNA foci were detected.

METHODS

Hematoxylin and eosin staining, immunohistochemical staining, as well as fluorescence in situ hybridization were used to investigate the cytoplasmic inclusions of ubiquitin and p62 and the (GGCCUG)n repeat RNA foci.

RESULTS

The present study showed both ubiquitin- and p62-positive inclusions in the cytoplasm of the inferior olivary nucleus of the Asidan patient, (GGCCUG)n RNA foci in neuronal nuclei of the cerebrum, cerebellum, inferior olive, spinal cord and temporal muscle, and three types of RNA foci, i.e. single small, multiple small and giant. Of interest is that the giant RNA foci, nearly 10 μm in diameter, that were detected in Purkinje cells, spinal motor neurons and most frequently in the inferior olivary nucleus, may be responsible for pivotal clinical symptoms of Asidan.

CONCLUSIONS

The present study is the first report to show neuronal cytoplasmic inclusion bodies and giant RNA foci in an Asidan patient. The relationships between the giant RNA foci and neurodegeneration have yet to be studied.

[A case of paclitaxel-resistant recurrent gastric cancer responsive to S-1 plus docetaxel]

We report the case of a patient with paclitaxel (PTX) -resistant recurrent gastric cancer who was effectively treated with S-1 plus docetaxel( DOC). A 62-year-old woman underwent total gastrectomy for Stage IV advanced gastric cancer (type 4, por 2>sig, pT4a (SE), pN3a, pP1, CY1) in 2009. Although S-1 was administered as first-line chemotherapy, recurrent peritoneal metastasis was diagnosed 22 months after surgery. S-1 plus irinotecan (CPT-11) was administered as second-line chemotherapy, and this was followed by weekly PTX (80 mg/m2) as third-line chemotherapy. However, computed tomography (CT) showed increased ascites and peritoneal wall thickening in the pelvis. As the tumor proved resistant to PTX, making the treatment ineffective, S-1( 80 mg/m2, day 1-14, q3w) plus DOC( 40 mg/m2, day 1, q3w) was initiated. Two months later, the ascites and peritoneal wall thickening in the pelvis disappeared. Twelve months after initiation of S-1 plus DOC chemotherapy, no sign of recurrence has been noted.

[A case of HER2-positive advanced gastric cancer successfully treated with a combination of capecitabine, cisplatin, and trastuzumab as first-line chemotherapy]

We report a case of human epidermal growth factor receptor(HER)2-positive advanced gastric cancer successfully treated with a combination of capecitabine, cisplatin(CDDP), and trastuzumab as first-line chemotherapy. A 66-year-old woman diagnosed as having advanced gastric cancer underwent chemotherapy after abdominal computed tomography (CT)revealed multiple metastases to the liver, lung, lymph nodes, and peritoneum. Histopathological examination indicated a type 3, tub1, cT3(SS), N3, H1, P1, M1(LYM, PUL), cStage IV gastric tumor. Because overexpression of HER2 protein was observed in primary tumor immunostaining, combination therapy of capecitabine+CDDP+trastuzumab was administered as first-line chemotherapy. After 4 courses, CT scans revealed decreased primary tumor size, liver lesion, lymph nodes, and elimination of the lung lesion, thereby suggesting a partial response(PR). The grade 3 adverse events were neutropenia, anemia, and anorexia. After discontinuation of CDDP because of elevation of serum creatinine levels, combination therapy with capecitabine and trastuzumab was continued.

[A case of advanced gastric cancer with para-aortic lymph node metastasis successfully treated with preoperative S-1/Lentinan chemotherapy followed by curative gastrectomy]

We report a case of advanced gastric cancer successfully treated with preoperative S-1/Lentinan (LTN)chemotherapy followed by curative gastrectomy. The patient was a 75-year-old man with right hypochondralgia. Endoscopic examination revealed a huge type 2 gastric cancer in the middle body of the stomach. Abdominal computed tomography (CT) revealed multiple perigastric lymph node metastases and bulky para-aortic lymph node metastases. The clinical diagnosis was cT 4N3M1( LYM) with cStage IV. We thought a complete resection would be difficult, so he was treated with S-1( 80 mg/m2 day 1-28/q6w) and LTN (2 mg weekly) in May 2010. After 3 courses, the primary lesion was markedly reduced, and gastric endoscopic biopsy showed no malignant lesion. After 4 courses, abdominal CT showed no lymph node swelling at the perigastric and para-aortic areas. After 5 courses, distal gastrectomy with D2 lymphadenectomy was performed. The histological diagnosis was ypT2( MP) N0M0, Stage IB. Histological features of the primary tumor and lymph nodes were judged to be Grade 2 and Grade 3, respectively. After surgery, S-1/LTN treatment was continued for 1 year. During this period, there were no serious adverse events. The patient has been in good health without recurrence for 28 months after surgery.

Chylothorax after coronary artery bypass grafting using the right internal thoracic artery

Chylothorax is a rare but serious complication of coronary artery bypass grafting (CABG) that results from disruption of the thoracic duct while harvesting the internal thoracic artery (ITA). A 78-year-old woman developed a large-volume milky pleural effusion 3 days after CABG. Biochemical analysis of the fluid resulted in a diagnosis of chylothorax. After failure of conservative medical treatment, including stopping her oral intake and starting total parenteral nutrition, surgical repair was performed via repeat median sternotomy. Intraoperative exploration revealed disruption of the thoracic duct or one of its tributaries close to the proximal portion of the right ITA, which was closed with interrupted sutures. In the majority of previous reports of chylothorax after CABG, the left ITA was used. However, harvesting of either the left or right ITA risks disruption of the thoracic duct and its tributaries, because of the high degree of anatomic variability of the thoracic duct system.

Fully nonlinear mode competitions of nearly bicritical spiral or Taylor vortices in Taylor-Couette flow

Interactions between nearly bicritical modes in Taylor-Couette flow, which have been concerned with the framework of weakly nonlinear theory, are extended to fully nonlinear Navier-Stokes computation. For this purpose, a standard Newton solver for axially periodic flows is generalized to compute any mixed solutions having up to two phases, which typically arise from interactions of two spiral or Taylor vortex modes. Also, a simple theory is developed in order to classify the mixed solutions. With these methods, we elucidate pattern formation phenomena, which have been observed in a Taylor-Couette flow experiment. Focusing on the counter-rotating parameter range, all possible classes of interaction of various solutions with different azimuthal and axial wave numbers are considered within our computational restriction, and we observe numerous connection branches, e.g., footbridge solutions. Some of the mixed solutions result in a three-dimensional wavy spiral solution with axial relative periodicity or an axially doubly periodic toroidally closed vortex solution. The possible connection of the former solution family to spiral turbulence, which has been observed in highly counter-rotating Taylor-Couette flow, is discussed.