Maturation and development of fetal pig intestinal tissue in immunodeficient mice.

PURPOSE: This study aimed to compare the degree of maturation and development of fetal pig segmental intestinal tissue with that of spheroids created by in-vitro reaggregation of dissociated fetal intestinal cells after transplantation into immunodeficient mice. METHODS: Fetal pig small intestines were transplanted as segmental grafts into the omentum and subrenal capsules of immunodeficient mice or enzymatically treated to generate single cells. Spheroids made by in-vitro reaggregation of these cells were transplanted into the subrenal capsules of immunodeficient mice. The segmental grafts and spheroids were harvested four and eight weeks after transplantation, and the structural maturity and in-vivo development of these specimens were histologically evaluated. RESULTS: The spheroids were engrafted and supplied blood vessels from the host mice, but an intestinal layered structure was not clearly observed, and there was almost no change in size. On the other hand, the segmental grafts formed deep crypts in the mucus membrane, the inner circular layer, and outer longitudinal muscles. The crypts of the transplanted grafts harvested at eight weeks were much deeper, and the smooth muscle layer and the enteric nervous system were more mature than those of grafts harvested at the fourth week, although the intestinal peristaltic wave was not observed. CONCLUSIONS: Spheroids created from fetal small intestinal cells could not form layered structures or mature sufficiently. Conversely, segmental tissues structurally matured and developed after in-vivo transplantation and are therefore potential grafts for transplantation.

Maturation and development of fetal pig intestinal tissue in immunodeficient mice

Purpose: This study aimed to compare the degree of maturation and development of fetal pig segmental intestinal tissue with that of spheroids created by in-vitro reaggregation of dissociated fetal intestinal cells after transplantation into immunodeficient mice. Methods: Fetal pig small intestines were transplanted as segmental grafts into the omentum and subrenal capsules of immunodeficient mice or enzymatically treated to generate single cells. Spheroids made by in-vitro reaggregation of these cells were transplanted into the subrenal capsules of immunodeficient mice. The segmental grafts and spheroids were harvested four and eight weeks after transplantation, and the structural maturity and in-vivo development of these specimens were histologically evaluated. Results: The spheroids were engrafted and supplied blood vessels from the host mice, but an intestinal layered structure was not clearly observed, and there was almost no change in size. On the other hand, the segmental grafts formed deep crypts in the mucus membrane, the inner circular layer, and outer longitudinal muscles. The crypts of the transplanted grafts harvested at eight weeks were much deeper, and the smooth muscle layer and the enteric nervous system were more mature than those of grafts harvested at the fourth week, although the intestinal peristaltic wave was not observed. Conclusions: Spheroids created from fetal small intestinal cells could not form layered structures or mature sufficiently. Conversely, segmental tissues structurally matured and developed after in-vivo transplantation and are therefore potential grafts for transplantation.

The Comparison of Postoperative Umbilical Port Site-Related Complications Between Transumbilical and Periumbilical Incision After Laparoscopic Surgery in Children.

Introduction: No studies have directly compared postoperative umbilical port site (UPS)-related complications between transumbilical and periumbilical incisions (TUI and PUI) after laparoscopic surgery in children. Patients and Methods: We conducted a retrospective review of 324 children of ≤15 years of age who underwent laparoscopic repair (LR) for inguinal hernia, via either a TUI or PUI, between 2010 and 2020. UPS-related complications, such as wound infection and umbilical deformity, were compared between TUI and PUI. We also investigated the risk factors for the development of UPS-related complications after LR. Results: TUIs and PUIs were used for 228 and 96 children, respectively. The incidence rates of postoperative wound infection and umbilical deformity in the PUI group were higher in comparison to the TUI group; although not to a statistically significant extent (7.3% versus 5.3%, P = .451, 6.3% versus 4.8%, P = .593). One case of incisional hernia at the UPS was seen in the TUI group. In the univariate analysis, sex, age, weight for age Z-score, nutrition status, insertion and closure time, total operative time, American Society of Anesthesiologists score, blood loss, and comorbidities were not significantly associated with the development of UPS-related complications after LR. Conclusion: The incidence of UPS-related complications in TUI and PUI was not significantly different. Due to the low incidence of UPS-related complications, it was difficult to draw conclusions regarding contributing factors; however, meticulous care should be taken to avoid UPS-related complications when closing the UPS (Ethical approval No. 2019-24).

Increase in pediatric complicated appendicitis during the COVID-19 pandemic: a multi-center retrospective study.

PURPOSE: An increase in the incidence of pediatric complicated appendicitis (CA) during the COVID-19 pandemic has been reported in many countries. We investigated how the pandemic has affected Japan. METHODS: We retrospectively reviewed children of ≤ 15 years old treated for acute appendicitis across 5 medical centers during the pandemic period (January to October in 2020), with the pre-pandemic period (January to October in 2017 to 2019) evaluated as a historical control. The incidence of CA and disease characteristics were then compared between the periods. RESULTS: The total number of patients was 55 in 2020 and 192 in 2017-2019. In all centers, the incidence of acute pediatric CA in the pandemic period significantly increased compared to the pre-pandemic period (18.2% vs. 32.7%, p = 0.02). On limiting our evaluation to the 3 institutions with reductions in patient numbers, the incidence of CA increased (16.3% vs. 37.9%, p = 0.01), and the duration of pre-operative symptoms was prolonged (1.3% vs. 1.7 days, p = 0.03). There were no significant differences in the age, sex, white blood cell count, C-reactive protein, or body temperature. No cases were diagnosed with SARS-CoV-2. CONCLUSIONS: The incidence of acute pediatric CA increased during the pandemic period. This may be related to an extended duration of symptoms due to individuals fearing contracting COVID-19 while visiting a hospital.

Risks and benefits of pediatric inguinal hernia repair: Conventional open repair vs laparoscopic percutaneous extraperitoneal closure.

INTRODUCTION: Considerable debate exists regarding the benefits of laparoscopic percutaneous extraperitoneal closure (LPEC) over conventional open repair (OR). We assessed the outcomes and feasibility of LPEC compared to OR for pediatric inguinal hernia (IH). METHODS: We retrospectively analyzed 570 children who underwent LPEC or OR. Parents decided the operative method after obtaining informed consent. Patient characteristics, operative time, complications and contralateral metachronous IH (CMIH) were compared between the groups. RESULTS: A total of 329 children underwent LPEC and 241 underwent OR. There was no significant difference in the incidence of recurrence or testicular ascent between the LPEC and OR groups (0.3% vs 0.4%, P = 0.825, 0.3% vs 0.8%, P = 0.391, respectively). No testicular atrophy was recognized in either group. One patient with postoperative chronic inguinal pain was recognized in each group. There was no surgical site infection (SSI) in the OR group; however, the LPEC group more frequently demonstrated umbilical port site (UPS)-related complications, such as incisional hernia, minor deformity, granuloma formation, cellulitis and superficial SSI. Ten (4.1%) developed CMIH in OR; in contrast, no case of CMIH was experienced after LPEC (P < 0.001). CONCLUSION: In conclusion, both LPEC and OR are feasible in the management of pediatric IH, because of their high success rates and low risk of complications. LPEC could be the superior procedure with respect to the prevention of CMIH. However, to maximize the merits of LPEC over OR, it is important to reduce UPS-related complications in LPEC. A longer follow-up is needed to assess male fertility in patients who receive LPEC.

Nonoperative management for umbilical hernia in infants using adhesive strapping.

BACKGROUND: The aim of this study was to evaluate the efficacy of adhesive strapping (AS) for umbilical hernia (UH) in infants. METHODS: A retrospective review of 30 mature infants without any treatment for UH between January 2006 and December 2008 and 87 infants (42 mature and 45 premature) who were treated with AS between January 2010 and December 2014 was conducted. The rate and age of closure of UH were compared between the groups and the complications and limitations of AS were evaluated. RESULTS: In the observation-only group, 24 UHs spontaneously closed at a mean age of 13.5 months, but a protruding umbilicus with redundant skin was present in three of 27 infants. Three infants had persistent UH, so a total of six infants, including the three with redundant skin and three with persistent UH, underwent surgery at the mean age of 30.0 months. In the AS group, 72 UHs were cured at a mean age of 4.3 months, which was significantly earlier than in the observation-only group (P < 0.01). Eleven infants did not continue AS because of skin irritation or discomfort. Four infants underwent repair due to persistent UH, but not for redundant skin of the umbilicus. CONCLUSIONS: Adhesive strapping is effective for promoting the early resolution of UH in infants and preventing the forming of redundant skin, which can reduce the need for surgical intervention. To achieve better results with AS, we recommend applying this technique before the UH grows large.

The outcomes of conservative management and the natural history of asymptomatic hydroceles in children.

PURPOSE: To elucidate the natural history of asymptomatic hydroceles (AHs) in children with conservative management and to discuss management strategies for AHs in children. METHODS: We retrospectively reviewed 113 children with AHs who were followed without immediate surgery. Patients were divided into four groups according to age at presentation; group 1: ≤ 1 month, group 2: 1-12 months, group 3: 12-24 months, and group 4: > 24 months. Ages at spontaneous resolution or surgery were reviewed. To assess the effect of AH on the testis, testicular size before and after conservative management was compared in 11 cases. RESULTS: In groups 1, 2, 3, and 4, spontaneous resolution occurred in 94.3%, 75.0%, 65.0%, and 33.3%, and the average time to resolution from presentation was 5, 5, 17, and 9 months, respectively. 41 patients underwent surgery at a mean age of 4.2 years. The testicular size did not differ significantly between before and after conservative management (14.4 vs. 14.5 mm, p = 0.483). CONCLUSION: About one-third of children over 2 years of age achieve spontaneous resolution. Hydroceles with conservative management may not affect the testicular size. Thus, initial conservative management before surgery is recommend for AHs in children, even over 2 years of age.

Management of inguinal hernia with prolapsed ovary in very low birthweight infants during neonatal intensive care unit hospitalisation.

AIM: Prolapsed ovary (PO) in an inguinal hernia (IH) may cause torsion and infarction; however, the management of IH with PO in very low birthweight (VLBW) infants during neonatal intensive care unit (NICU) hospitalisation remains inconsistent. METHODS: The medical records of 47 IHs in 30 VLBW infants during NICU hospitalisation between 2008 and 2017 were reviewed retrospectively. RESULTS: Of the 47 IHs, PO was diagnosed in 18 (38.3%). Post-natal age and body weight at diagnosis of IH with PO were 71 (44-172) days and 2120 (1305-2965) g, respectively. Seventeen IHs with PO underwent surgery for correction electively just before discharge from the NICU at the age and body weight of 94 (51-187) days and 2645 (2340-2945) g, respectively. Therefore, the time interval between diagnosis and surgery was 15 (7-90) days. There was no torsion of ovary before surgery and no postoperative complications, including apnoea and recurrence. CONCLUSIONS: The high incidence of IH with PO in VLBW infants during NICU hospitalisation was confirmed in this study. Under careful observation, elective IH repair just before discharge from the NICU could be one acceptable option for the management of IH with PO in VLBW infants during NICU hospitalisation to prevent torsion and infarction of ovary.

Colonoscopic diagnosis and reduction of recurrent intussusception owing to Henoch-Schönlein purpura without purpura.

About 50-75% of patients with Henoch-Schönlein purpura (HSP) develop gastro-intestinal symptoms with surgical complications such as intussusception occurring in 0.7-13.6%. In 10-40% of patients, however, gastro-intestinal manifestations may precede the onset of purpura. In patients with gastro-intestinal tract involvement without purpura, confirming the diagnosis of HSP and determining the appropriate treatment remains difficult. A seven-year-old boy presented with recurrent intussusception owing to HSP without purpura. It was confirmed pathologically and treated via colonoscopy. Early colonoscopic intervention can contribute to the early diagnosis of HSP and its subsequent management by avoiding unnecessary surgical invasion.

Venous thromboembolism in two adolescents with Down syndrome.

Kurokami T, Takasawa R, Takeda S, Kurobe M, Takasawa K, Nishioka M, Shimohira M. Venous thromboembolism in two adolescents with Down syndrome. Turk J Pediatr 2018; 60: 429-432. Although venous thromboembolic events are relatively rare in children, they are an increasingly recognized clinical entity in pediatric tertiary care hospitals. Although vascular disorders are prevalent with Down syndrome, it remains unclear whether Down syndrome patients are at higher risk for venous thromboembolic events. We report two adolescent cases with Down syndrome who unexpectedly developed venous thromboembolism in a general care unit. Our cases had a few risk factors; laparoscopic radical surgery for Hirschsprung's disease with central venous catheterisation in Case 1, and bacterial hepatic abscess in Case 2. Despite preventive heparinization with catheterisation and minor surgery in Case 1 and non-sepsis in Case 2, bed rest for only a few days triggered sudden onset of deep vein thrombosis in lower limbs with pulmonary thromboembolism in both cases. We speculate that the characteristics of Down syndrome, including physical and behavioural problems, might cause venous thromboembolic events. Thus, we should pay more attention to the relationship specifically between venous thromboembolism and Down syndrome, especially in adolescents, and increase prevention, early detection and treatment efforts.

Inguinal hernia in very low-birthweight infants: Follow up to adolescence.

BACKGROUND: This study reviewed the medical records of very low-birthweight infants (VLBWI) followed up to adolescence, with emphasis on inguinal hernia (IH), to discuss the ideal time for IH repair in VLBWI. METHODS: Medical records from 274 VLBWI treated in the neonatal intensive care unit (NICU) between 1994 and 1999 were collected retrospectively. Outpatient data after NICU discharge were included. Additionally, a follow-up study was undertaken via questionnaire sent to the families of VLBWI in 2011. RESULTS: During NICU hospitalization, IH was diagnosed in 39 of 274 VLBWI, and two developed incarceration. Thirty-eight VLBWI were discharged with known hernia, and elective repair was performed in 19. Three developed incarceration before elective repair at the mean age of 316 days. In the remaining 18 cases of IH, spontaneous regression occurred at a mean age of 180 days and repair was not performed. New IH appeared in 25 VLBWI after NICU discharge. CONCLUSIONS: The high incidence of IH in VLBWI was confirmed during follow up to adolescence. The rate of incarceration was low and the incidence of spontaneous regression was high. Observation up to 6 months without surgery, with the expectation of spontaneous regression, is one option to avoid unnecessary surgery, but repair should be performed before 10 months to reduce the risk of incarceration. Further large, prospective, and randomized controlled studies with a long follow up are necessary to validate the present results and to define the ideal time for IH repair in VLBWI.

Laparoscopic percutaneous extraperitoneal closure for inguinal hernia: learning curve for attending surgeons and residents.

BACKGROUND/PURPOSE: Laparoscopic percutaneous extraperitoneal closure (LPEC) for pediatric inguinal hernia is a simple technique in which a purse-string suture made of nonabsorbable material is placed extraperitoneally around the hernia orifice by a special suture needle (Lapaherclosure™). Concerns have been raised about the extensive learning curve for both attending surgeons and residents to master this technique. This study assesses the difference in learning curves for the safe performance of LPEC by attending surgeons and residents. METHODS: A retrospective analysis was performed on the surgical charts of 409 consecutive patients (175 girls, 234 boys) who had undergone LPEC for inguinal hernia repair from December 2005 to December 2011 at Jikei University Hospital. The number of operation needed by attending surgeons and residents to reach the appropriate operation time was analyzed by the Mann-Whitney U test. RESULTS: LPEC was performed by three attending surgeons and four residents who had not previously performed LPEC. The standard operation time for LPEC by attending surgeons who have performed more than 100 LPEC cases safely is 30 min. In our study, the attending surgeons needed a mean of 12 operations (range, 10-16) to reach 30 min for LPEC. Three residents needed a mean of 31 operations (range, 27-33) to reach 30 min for LPEC. The fourth resident could not perform LPEC in 30 min or less. The difference between the number of operations needed by the attending surgeons and the residents to perform LPEC safely was statistically significant (P < 0.05). The overall incidence of contralateral patent processus vaginalis was 47.9 %. CONCLUSIONS: Our learning curve analysis showed that whereas attending surgeons needed a mean of 12 operations to perform LPEC repairs safely in 30 min or less, residents needed more than 30 operations to safely perform LPEC repairs without supervision.

Delayed primary reconstruction of esophageal atresia and distal tracheoesophageal fistula in a 471-g infant.

INTRODUCTION: Waterston et al. have classified the risk of morbidity in infants with esophageal atresia and tracheoesophageal fistula. However, few cases of esophageal atresia with distal tracheoesophageal fistula in extremely low birth weights infants have been reported. In such infants, the selection of primary reconstruction or staged repair remains controversial. In the present report, we describe the difficulties of perioperative management of such small infants and discuss how to rescue them. PRESENTATION OF CASE: A 471-g female infant was delivered at 28 weeks' gestation via cesarean section. Esophageal atresia with distal tracheoesophageal fistula was diagnosed. Esophageal banding and gastrostomy were performed via laparotomy on day 1. On day 74, when the infant weighed almost 1000g, airway management was discontinued. On day 136, endotracheal intubation again became necessary because of respiratory problems, and the esophagus was reconstructed on day 141. Despite this operation, the patient died on day 276 because of continuing respiratory problems. DISCUSSION: Esophageal banding is considered an appropriate treatment for respiratory problems in such extremely low weight infants. However, the timing of dissection of the tracheoesophageal fistula after esophageal banding is extremely important. CONCLUSION: In the present case, ligation of the tracheoesophageal fistula and esophageal reconstruction should have been performed as soon as possible.

Hepatotoxin-induced changes in the adult murine liver promote MYC-induced tumorigenesis.

BACKGROUND: Overexpression of the human c-MYC (MYC) oncogene is one of the most frequently implicated events in the pathogenesis of hepatocellular carcinoma (HCC). Previously, we have shown in a conditional transgenic mouse model that MYC overexpression is restrained from inducing mitotic cellular division and tumorigenesis in the adult liver; whereas, in marked contrast, MYC induces robust proliferation associated with the very rapid onset of tumorigenesis in embryonic and neonatal mice. METHODOLOGY/PRINCIPAL FINDINGS: Here, we show that non-genotoxic hepatotoxins induce changes in the liver cellular context associated with increased cellular proliferation and enhanced tumorigenesis. Both 5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) and carbon tetrachloride (CCl(4)) cooperate with MYC to greatly accelerate the onset of liver cancer in an adult host to less than 7 days versus a mean latency of onset of over 35 weeks for MYC alone. These hepatotoxin-enhanced liver tumors grossly and histologically resemble embryonic and neonatal liver tumors. Importantly, we found that MYC overexpression is only capable of inducing expression of the mitotic Cyclin B1 in embryonic/neonatal hosts or adult hosts that were treated with either carcinogen. CONCLUSION/SIGNIFICANCE: Our results suggest a model whereby oncogenes can remain latently activated, but exposure of the adult liver to hepatotoxins that promote hepatocyte proliferation can rapidly uncover their malignant potential.

Wnt/beta-catenin signaling in murine hepatic transit amplifying progenitor cells.

BACKGROUND & AIMS: Oval cells are postnatal hepatic progenitors with high proliferative potential and bipotent differentiation ability to become hepatocytes and cholangiocytes. Because Wnt/beta-catenin signaling is a known regulatory pathway for liver development and regeneration, we studied the role of Wnt signaling in oval cells using a mouse model of chronic liver injury. METHODS: A 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-enriched diet was used to stimulate oval cell proliferation. Livers were harvested for histologic analysis and determination of Wnt family gene expression by quantitative reverse transcription-polymerase chain reaction and in situ hybridization. The transgenic beta-catenin reporter mouse (TOPGAL) was use to confirm canonical Wnt/beta-catenin signal transduction in proliferating oval cells within atypical ductal proliferations (ADPs). Confocal fluorescence microscopy and immunohistochemistry was used to confirm colocalization of beta-catenin with the oval cell antigen A-6. RESULTS: Several Wnt ligands were significantly induced in the liver of DDC-fed mice and localized to proliferating cells in and adjacent to the ADPs. Oval cells isolated from DDC-fed mouse livers showed the presence of active beta-catenin in the nucleus along with cell-cycle entry in response to purified Wnt3a in vitro. Moreover, Wnt3a-induced beta-catenin/T-cell factor/lymphoid enhancer factor (TCF/LEF) transcriptional activation was quantified by TCF/LEF luciferase reporter assays. CONCLUSIONS: From these data, we conclude that oval cells respond to Wnt ligands (Wnt3a) in vitro with an increase in amino-terminus dephosphorylated beta-catenin and cell-cycle entry and that canonical Wnt/beta-catenin/TCF signaling is active in proliferating facultative hepatic progenitor cells in vivo. These findings may lend insight to the consequences of increased canonical Wnt signaling during periods of chronic liver injury.

Esophageal replacement using a reversed gastric tube for lye stricture in a child: report of a case.

A 5-year-old girl ingested lye, a detergent used in electric dishwashers. She was transferred to our hospital after balloon dilatation, performed for stenosis resulting from corrosive esophagitis, was complicated by esophageal perforation causing mediastinitis. Although the mediastinitis resolved with conservative treatment, the stenosis did not improve. Therefore, we performed esophageal replacement using a reversed gastric tube, which successfully relieved the obstruction, although she still had slight gastroesophageal reflux 6 months postoperatively.

Donor-derived, liver-specific protein expression after bone marrow transplantation.

BACKGROUND: Bone marrow transplantation (BMT) may represent a novel mechanism to deliver a functional gene to a deficient liver. Bone marrow-derived hepatocytes are rare and without a defined contribution to liver function. Consequently, the clinical significance of BMT to treat liver disease is unclear. We sought to quantify bone marrow-derived hepatocyte protein expression after BMT and determine whether the process is inducible with liver injury. METHODS: Mice transgenic for human alpha-1 antitrypsin (hAAT) under a hepatocyte-specific promoter were used as bone marrow donors. Adenoviral transduction of modified urokinase plasminogen activator (Ad-muPA) was used to induce liver injury. Eight weeks after lethal irradiation and BMT, recipients were stratified into two groups: BMT alone (n = 5) and BMT + Ad-muPA (n= 10). Both groups of animals were bled before (t = 0) and at 2, 4, 8, and 16 weeks after Ad-muPA administration, and the serum samples were assessed for hAAT by enzyme-linked immunosorbent assay. RESULTS: Transgenic donor mice expressed 5 to 10 mg/mL of hAAT. Recipients of BMT alone expressed less than 80 ng/mL of hAAT over all time periods. Animals receiving BMT + Ad-muPA showed sustained and stable hAAT expression of approximately 200 ng/mL. Differences were statistically significant at each time point. CONCLUSION: Serum protein levels from liver-specific transgene expression are detectable and persist after BMT. Expression is low, but inducible with liver injury. We are currently developing strategies to augment donor-derived, liver-specific protein expression after BMT.