Long- term outcomes of congenital tracheal stenosis after slide tracheoplasty.

PURPOSE: Long-term outcomes of slide tracheoplasty in patients with congenital tracheal stenosis (CTS) have rarely been reported. This study aimed to clarify the long-term outcomes of CTS after slide tracheoplasty. METHODS: The medical records of 33 patients who underwent slide tracheoplasty for CTS at our institution between January 2005 and July 2018, with a follow-up duration > 5 years, were retrospectively reviewed. Patients' characteristics, perioperative condition, operative management, postoperative course, tracheal stenosis rates and growth data, were collected from medical records. RESULTS: The median operative age, minimum tracheal diameter, length of stenosis, duration of hospital stays, and follow-up duration were 8 months, 2.4 mm, 35 mm, 39 days, and 90 months, respectively. One patient died of bleeding in the right lung at 126 months postoperatively. Among the 10 patients requiring postoperative tracheostomy, seven were successfully decannulated at a median of 65 months postoperatively. Tracheal stenosis rates improved postoperatively and were subsequently maintained. Growth impairment and psychomotor delay were observed in 9 and 16 patients, respectively with significant differences found only in cases with genetic abnormalities and not in tracheal stenosis severity. CONCLUSION: Slide tracheoplasty for CTS leads to favorable long-term outcomes. However, various associated anomalies may influence growth and psychomotor development, emphasizing the importance of adequate support.

Endosurgery workshop to improve the confidence of novice pediatric surgeons in performing laparoscopic hepaticojejunostomy.

PURPOSE: This study assessed the efficacy of a high-impact, short-term workshop in honing the laparoscopic hepaticojejunostomy technical skills and self-confidence of novice pediatric surgeons, focusing on vertical needle driving and knot tying. METHODS: Lectures, hands-on sessions, pre- and post-workshop evaluations, and training using porcine models were conducted to refine basic and advanced skills. The "hepaticojejunostomy simulator" was used for comparative analysis of precision in pre- and post-workshop vertical needle driving and knot tying. Participants self-evaluated their skills and confidence on a 5-point scale. RESULTS: After the workshop, eight inexperienced pediatric surgeons demonstrated a significant improvement in hepaticojejunostomy suturing task completion rates and needle-driving precision at the jejunum and hepatic duct. However, the A-Lap Mini Endoscopic Surgery Skill Assessment System indicated no significant improvements in most assessed parameters, except for the full-layer closure score (p = 0.03). However, a significant increase in participants' confidence levels in performing laparoscopic hepaticojejunostomy was observed. CONCLUSION: The workshop augmented technical proficiency and confidence in young pediatric surgeons. The combination of lectures, practical exposure, and model training is an effective educational strategy in pediatric surgical instruction.

Colonic diverticulitis in children: A retrospective study of 16 patients.

BACKGROUND: Pediatric colonic diverticulitis (CD) is a rare entity. This study aimed to investigate the clinical features of CD in children. METHODS: We performed a retrospective chart review of children aged ≤15 years who were diagnosed with CD in our institution from May 2006 to November 2016. RESULTS: Sixteen patients were diagnosed with CD. All CD cases were observed to be solitary cecal diverticulitis; 14 cases were detected using ultrasound and the other two cases were diagnosed by computed tomography. Five patients were male (31.3%), and the median age was 12 years (range, 8-15 years). Initial symptoms were fever (temperature >38°C) in six (37.5%) patients, right lower quadrant abdominal pain in 16 (100%), anorexia in eight (50%), and nausea / vomiting in five (31.3%). A patient experienced persistent constipation; however, diarrhea was not observed as a clinical symptom in any patient. The median duration from symptom onset to admission was 1 day (range, 0-4 days), and the median length of hospital stay was 6 days (range, 4-10 days). All CD cases were treated with intravenous antibiotics. The median follow-up period was 90 months (range, 37-163 months), and during this period, recurrence of CD was observed in three (18.8%) patients. At recurrence, antibiotics were administered in all cases. CONCLUSIONS: In this study, all cases of CD were solitary cecal diverticulitis, and ultrasound was useful for the diagnosis of cecal diverticulitis in children. Non-operative treatment should be recommended as an initial treatment for CD in children.

Point mutagenesis in mouse reveals contrasting pathogenetic effects between MEN2B- and Hirschsprung disease-associated missense mutations of the RET gene.

Missense mutations of the RET gene have been identified in both multiple endocrine neoplasia (MEN) type 2A/B and Hirschsprung disease (HSCR: congenital absence of the enteric nervous system, ENS). Current consensus holds that MEN2A/B and HSCR are caused by activating and inactivating RET mutations, respectively. However, the biological significance of RET missense mutations in vivo has not been fully elucidated. In the present study, we introduced one MEN2B-associated (M918T) and two HSCR-associated (N394K and Y791F) RET missense mutations into the corresponding regions of the mouse Ret gene by genome editing (RetM919T , RetN396K and RetY792F ) and performed histological examinations of Ret-expressing tissues to understand the pathogenetic impact of each mutant in vivo. RetM919T/+ mice displayed MEN2B-related phenotypes, including C-cell hyperplasia and abnormal enlargement of the primary sympathetic ganglia. Similar sympathetic phenotype was observed in RetM919T/- mice, demonstrating a strong pathogenetic effect of the Ret M918T by a single-allele expression. In contrast, no abnormality was found in the ENS of mice harboring the Ret N394K or Y791F mutation. Most surprisingly, single-allele expression of RET N394K or Y791F was sufficient for normal ENS development, indicating that these RET mutants exert largely physiological function in vivo. This study reveals contrasting pathogenetic effects between MEN2B- and HSCR-associated RET missense mutations, and suggests that some of HSCR-associated RET missense mutations are by themselves neither inactivating nor pathogenetic and require involvement of other gene mutations for disease expressivity.

Analysis of predictive factors for perforated appendicitis in children.

BACKGROUND: The aim of this research was to investigate the diagnostic value of objective factors present at admission for identifying predictive markers of perforated appendicitis in children. METHODS: We performed a retrospective case review of 319 children aged ≤15 years who underwent treatment for acute appendicitis at our institution over a 6-year period from January 2011 to December 2016. Univariate and multivariate analyses were performed to identify risk factors for perforation of acute appendicitis in children. RESULTS: In the 6-year period, 319 patients underwent treatment for acute appendicitis, of whom 72 (22.6%) had perforated appendicitis. Multivariate analysis revealed five independent factors predicting perforated appendicitis at admission: longer symptom duration (≥2 days), fever (axillary temperature ≥38.0 °C), elevated C-reactive protein level (≥3.46 mg/dL), appendiceal fecalith on imaging, and ascites on imaging. Among patients with all five risk factors, 93.3% had perforated appendicitis. None of the patients without any of these factors had a perforated appendicitis. CONCLUSIONS: Longer symptom duration (≥2 days), fever (axillary temperature ≥38.0 °C), elevated C-reactive protein level, and the presence of appendiceal fecalith and ascites on imaging are independent and objective factors predicting perforated appendicitis at admission. These risk factors have the potential to be helpful as an ancillary index for physicians determining the severity of appendicitis.

In Vivo Introduction of mRNA Encapsulated in Lipid Nanoparticles to Brain Neuronal Cells and Astrocytes via Intracerebroventricular Administration.

Gene therapy is a promising strategy for curing certain types of brain diseases. Supplementation of therapeutic proteins such as aromatic amino acid decarboxylase (AADC) or nerve growth factor (NGF) have been reported to be successful examples of such treatments. However, there are safety concerns because these systems are based on virus-based gene vectors. A safe and efficient artificial carrier is thus urgently needed as an alternative. In this study, an mRNA based artificial gene carrier was introduced into the mouse brain via intracerebroventricular administration. As a carrier, a lipid nanoparticle (LNP) composed of environmentally sensitive lipid-like materials called an SS-cleavable proton-activated lipid-like material is used. The apolipoprotein E mediated cellular uptake of the lipid nanoparticles is one of the key features for its superior and homogeneous transfection activity compared to commercially available transfection reagents in both in vitro and in vivo situations. Immunostaining of brain specimens suggested that exogenous proteins can be introduced into neuronal cells as well as astrocytes using the mRNA-based gene carrier. This cannot be achieved using DNA-based artificial gene carriers. The findings suggest that a combination of an mRNA and a lipid based delivery system have great promise as a platform for the treatment of brain disorders.

Ebf3+ niche-derived CXCL12 is required for the localization and maintenance of hematopoietic stem cells.

Lympho-hematopoiesis is regulated by cytokines; however, it remains unclear how cytokines regulate hematopoietic stem cells (HSCs) to induce production of lymphoid progenitors. Here, we show that in mice whose CXC chemokine ligand 12 (CXCL12) is deleted from half HSC niche cells, termed CXC chemokine ligand 12 (CXCL12)-abundant reticular (CAR) cells, HSCs migrate from CXCL12-deficient niches to CXCL12-intact niches. In mice whose CXCL12 is deleted from all Ebf3+/leptin receptor (LepR)+ CAR cells, HSCs are markedly reduced and their ability to generate B cell progenitors is reduced compared with that to generate myeloid progenitors even when transplanted into wild-type mice. Additionally, CXCL12 enables the maintenance of B lineage repopulating ability of HSCs in vitro. These results demonstrate that CAR cell-derived CXCL12 attracts HSCs to CAR cells within bone marrow and plays a critical role in the maintenance of HSCs, especially lymphoid-biased or balanced HSCs. This study suggests an additional mechanism by which cytokines act on HSCs to produce B cells.

Efficacy and Safety of Add-on Mirogabalin to NSAIDs in Lumbar Spinal Stenosis with Peripheral Neuropathic Pain: A Randomized, Open-Label Study.

INTRODUCTION: In Japan, conservative therapy for patients with lumbar spinal stenosis (LSS) includes non-steroidal anti-inflammatory drugs (NSAIDs), prostaglandin E1, tramadol, physical/exercise therapy, and nerve blocks. Mirogabalin, a selective oral α2δ ligand, is approved for treating peripheral neuropathic pain, though data regarding visual analog scores (VAS) for pain in patients with LSS are limited. We investigated the efficacy and safety of mirogabalin as an add-on treatment in patients with LSS taking NSAIDs compared with patients taking NSAIDs only. METHODS: This multicenter, randomized, open-label study (MiroTAS) was conducted at 32 centers in Japan between June 2020 and October 2021. Patients were randomly assigned to mirogabalin and NSAIDs or NSAIDs alone in a 1:1 ratio. NSAIDs were administered according to their Japanese package inserts; mirogabalin was administered based on renal function [creatinine clearance (CrCL) ≥ 60 mL/min, 5 mg twice daily (BID) in Weeks 1-2, 10 mg BID in Weeks 3-4, and 15 or 10 mg BID after Week 5; CrCL 30 to < 60 mL/min, 2.5 mg BID Weeks 1-2, 5 mg BID Weeks 3-4, and 7.5 or 5 mg BID after Week 5]. The primary endpoint was the change in VAS score for leg pain from baseline to Week 12. Secondary endpoints were quality of life, evaluated using the EuroQol five-dimensional descriptive system (EQ-5D-5L) (at baseline and Week 12) and Patient Global Impression of Change (PGIC) (at Week 12), and safety. Change in VAS score at Week 12 was calculated using a linear mixed model for repeated measures. The safety endpoints were treatment-emergent adverse events (TEAEs) and adverse drug reactions. RESULTS: In total, 220 patients who met the eligibility criteria were enrolled. In the mirogabalin and NSAIDs and NSAIDs groups, mean ages (67.8 vs. 70.9 years), proportions of female patients (54.5% vs. 49.0%), mean body weights (63.9 vs. 62.0 kg), mean CrCL values (81.5 vs. 70.7 mL/min), proportions of patients with CrCL 30 to < 60 mL/min (27.3% vs. 33.7%), mean VAS scores (63.8 vs. 62.8 mm), and proportions of patients with VAS score ≥ 60 (53.6% vs. 52.9%) at enrollment were similar. The median durations of LSS were 9.0 and 11.0 months and the spine pain DETECT questionnaire (SPDQ) scores were 6.8 and 7.8, respectively. The least square (LS) mean change in VAS score from baseline to Week 12 was - 24.1 mm in the mirogabalin and NSAIDs group and - 14.2 mm in the NSAIDs group (both P < 0.0001 vs. baseline). The difference in LS mean was - 9.9 [95% confidence interval (CI), - 18.0, - 1.8] (P = 0.0174). The improvement in EQ-5D-5L score at Week 12 was significantly greater in the mirogabalin and NSAIDs group versus the NSAIDs group [mean difference, 0.0529 (95% CI, 0.0036, 0.1022), P = 0.0357]. At Week 12, the proportions of patients with PGIC scores ≤ 3 and ≤ 2 were higher in the mirogabalin and NSAIDs group vs. the NSAIDs group (76.2% vs. 50.0%, P = 0.0006, and 47.6% vs. 32.4%, P = 0.0523). In the mirogabalin and NSAIDs group, the incidences of TEAEs and adverse drug reactions were 60.9% and 57.3%, respectively, and the most common TEAEs were somnolence (30.0%) and dizziness (25.5%). CONCLUSIONS: The addition of mirogabalin to NSAIDs improved VAS, EQ-5D-5L, and PGIC. The main TEAEs were somnolence and dizziness. The addition of mirogabalin to NSAIDs improved peripheral neuropathic pain associated with LSS and raised no new safety concerns. TRIAL REGISTRATION: Japan Registry of Clinical Trials (jRCTs021200007).

Laparoscopic fundoplication for a child with abdominal intrathecal Baclofen pump.

This is the first case report describing a laparoscopic fundoplication in a child with an intrathecal Baclofen pump which was inserted because of severe spasticity secondary to cerebral palsy. The child had symptoms of gastroesophageal reflux with recurrent episodes of aspiration pneumonia. These were managed with a gastrostomy and conservative therapy with no success. The presence of an intrathecal Baclofen pump makes abdominal surgery challenging and carries the risk of pump infection with its associated sequelae. However, we performed a successful laparoscopic fundoplication with no intraoperative complications and the child was asymptomatic at 18 months follow-up.

PEGylation of the GALA Peptide Enhances the Lung-Targeting Activity of Nanocarriers That Contain Encapsulated siRNA.

A α-helical GALA peptide (WEAALAEALAEALAEHLAEALAEALEALAA) has been found to possess dual functions: a pH-dependent inducer of endosomal escape, and a ligand that targets lung endothelium. In the present study, the flexibility of GALA was improved by modifying the edge with polyethylene glycol linker, to increase lung-targeting activity. We first investigated the uptake of the GALA-modified liposomes in which GALA was directly conjugated to the lipid (Cholesterol: GALA/Chol) or the phospholipid-PEG (GALA/PEG2000). The liposomes that were modified with GALA/PEG2000 (GALA/PEG2000-LPs) were taken up at a higher level by human lung endothelial cells (HMVEC-L), in comparison with particles that were modified with GALA/Chol (GALA/Chol-LPs). Small-interfering RNA-encapsulating liposomal-based nanocarriers (multifunctional envelope-type nano device: MEND) that were formulated with a vitamin E-scaffold SS-cleavable pH-activated lipid-like material, namely GALA/PEG2000-MENDssPalmE were also modified with GALA/PEG2000. Gene silencing activity in the lung endothelium was then evaluated against an endothelial marker; CD31. In comparison with the unmodified MENDssPalmE, GALA/PEG2000-MENDssPalmE exhibited a higher silencing activity in the lung. Optimization of GALA/PEG2000-MENDssPalmE resulted in silencing activity in the lung with an ED50 value of 0.21 mg/kg, while non-specific gene silencing in liver was marginal. Collectively, PEGylated GALA is a promising device for use in targeting the lung endothelium.

Effect of hydrophobic scaffold on the cellular uptake and gene transfection activities of DNA-encapsulating liposomal nanoparticles via intracerebroventricular administration.

Efficient DNA carriers are needed as a gene medication for curing brain disorders. In the present study, the function of a neutral lipid envelope-type nanoparticle (LNP) encapsulating pDNA was evaluated after intracerebroventricular administration. The lipid envelope was composed of a series of SS-cleavable and pH-activated lipid like materials (ssPalm) including myristic acid, vitamin A and vitamin E in the hydrophobic scaffold (LNPssPalmM, LNPssPalmA, LNPssPalmE, respectively). The LNPssPalmA and LNPssPalmE were extensively distributed in the corpus callosum, and then gene expression occurred mainly astrocytes in this region, while not in LNPssPalmM. The recombinant human ApoE3-dependent enhancement of the uptake into an astrocyte-derived cell line (KT-5) was observed in LNPssPalmA and LNPssPalmE. Thus, ApoE in the brain plays a key role in the cellular uptake of these particles by astrocytes, and this uptake is dependent on the structure of the hydrophobic scaffold.

Application of apolipoprotein E-modified liposomal nanoparticles as a carrier for delivering DNA and nucleic acid in the brain.

An innovative drug delivery technology is urgently needed to satisfy unmet medical needs in treating various brain disorders. As a fundamental carrier for plasmid DNA or nucleic acids, we developed a liposomal nanoparticle (multifunctional envelope-type nano device [MEND]) containing a proton-ionizable amino lipid (YSK-MEND). Here we report on the impact of apolipoprotein E (ApoE) modification on the function of YSK-MEND in terms of targeting brain cells. The cellular uptake and function of YSK-MEND encapsulating short interference RNA or plasmid DNA were significantly improved as a result of ApoE modification in mouse neuron-derived cell lines (Neuro-2a and CAD). Intracerebroventricular administration of ApoE-modified YSK-MEND (ApoE/YSK-MEND) encapsulating plasmid DNA also resulted in higher transgene expression in comparison with YSK-MEND that was not modified with ApoE. Moreover, observation of fluorescence-labeled ApoE/YSK-MEND and expression of mCherry (fluorescence protein) derived from plasmid DNA indicated that this carrier might be useful for delivering and conferring transgene expression in neural stem cells and/or neural progenitor cells. Thus, this system may be a useful tool for the treatment of neurodegenerative disease.