[A Surgical Case of Currarino Syndrome with Syringomyelia].

Currarino syndrome is characterized by a triad of anorectal malformations, sacral defects, and presacral masses. Although it is not extremely rare, this report presents a surgical case of Currarino syndrome with syringomyelia and discusses related literature. The patient is a girl, aged 2 years and 2 months, who presented with marked constipation, chronic cystitis, and lower limb weakness. After examining the patient through magnetic resonance imaging, we diagnosed her with rectal compression due to meningocele and syringomyelia. The base of the meningocele was detached, and the spinal cord was untethered. One week after surgery, her lower limb weakness and constipation improved. Following up on symptoms and performing imaging is essential to determine a treatment plan for Currarino syndrome. (Received 28 February, 2023; Accepted 22 March, 2023; Published 1 August, 2023).

The magnitude of CXCR4 signaling regulates resistance to quizartinib in FLT3/ITD+ cells via RUNX1.

CXCR4 antagonists sensitize FLT3/ITD+ AML cells to FLT3 inhibitors; however, CXCR4 signaling can induce apoptosis in AML cells, raising the question of whether CXCR4 signaling exerts divergent effects on FLT3/ITD+ cells. The present study investigated the paradoxical function of CXCR4 in resistance to FLT3 inhibitors. The FLT3 inhibitor quizartinib significantly decreased the number of FLT3/ITD+ Ba/F3 cells, whereas 1 ng/ml CXCL12 showed a significant protective effect against quizartinib. In contrast, CXCL12 over 100 ng/ml significantly decreased FLT3/ITD+ cell viability with concomitant downregulation of Runx1. Moreover, the survival of FLT3/ITD+ Ba/F3 or MOLM13 cells with low surface CXCR4 expression incubated with quizartinib was significantly enhanced by 100 ng/ml CXCL12; however, this protective effect of CXCL12 against quizartinib was barely detected in cells with high surface CXCR4 expression. Although silencing Runx1 downregulated CXCR4 expression, RUNX1 expression levels were significantly higher in CXCR4LOW FLT3/ITD+ Ba/F3 cells incubated with 100 ng/ml CXCL12 than in CXCR4HIGH cells, coincident with an increase in FLT3 phosphorylation. Silencing RUNX1 partially abrogated resistance to quizartinib in CXCR4LOW cells incubated with CXCL12, whereas ectopic RUNX1 significantly restored resistance in CXCR4HIGH cells. These results indicate that CXCR4 signaling of different magnitudes paradoxically regulates resistance to quizartinib in FLT3/ITD+ cells via RUNX1.

Laryngeal web with 22q11.2 deletion syndrome.

Laryngeal web is a rare congenital or acquired disease that results in airway stenosis. Depending on the severity of atresia, patients with laryngeal web show a wide variety of symptoms ranging from asymptomatic to life-threatening respiratory dysfunction that may require emergency tracheostomy immediately after birth. We report a neonatal case of laryngeal web with 22q11.2 deletion syndrome. Post-delivery, the infant showed dysphonia and had a ventricular septal defect with characteristic craniofacial features. The infant underwent an endoscopic incision of the web and cardiac surgery. Among patients with laryngeal web, 30% have 22q11.2 deletion syndrome. 22q11.2 deletion syndrome is the most common chromosomal microdeletion syndrome and the second most common chromosomal abnormality associated with congenital heart disease. Therefore, if an infant has laryngeal web with comorbidities such as congenital heart disease, 22q11.2 deletion syndrome should be considered in differential diagnosis.

Long-term renal follow up of preterm neonates born before 35 weeks of gestation.

BACKGROUND: The hypothesis of the Developmental Origins of Health and Disease states that environmental factors during fetal and infantile life are risk factors for some chronic diseases in adulthood. Few studies, however, have confirmed this hypothesis early in childhood. Therefore, we assessed how premature birth and low-birthweight (LBW) affect the renal function of Japanese children. METHODS: This retrospective study surveyed 168 patients who were born before 35 weeks of gestation and were cared for at the present neonatal intensive care unit. Follow-up duration was >2 years. Serum creatinine (sCr) and estimated glomerular filtration rate (eGFR) recorded in medical records were reviewed. RESULTS: The eGFR at 2 years of age was significantly correlated with birthweight and gestational age (P < 0.01). Approximately 10.7% of the children had low eGFR (<90 mL/min/1.73 m2 ) without clinical symptoms or abnormal urine examination. These children had high sCr on day 7 after birth (P < 0.01) and delayed recovery of these levels during the first month after birth. CONCLUSION: Premature gestational age and LBW directly affect renal function in young children. High sCr on day 7 after birth is a risk factor for chronic kidney disease in children. Careful follow up of renal function is therefore required for premature infants and infants with LBW beginning in early childhood to prevent renal dysfunction.

Internal Tandem Duplication in FLT3 Attenuates Proliferation and Regulates Resistance to the FLT3 Inhibitor AC220 by Modulating p21Cdkn1a and Pbx1 in Hematopoietic Cells.

Internal tandem duplication (ITD) mutations in the Fms-related tyrosine kinase 3 (FLT3) gene (FLT3-ITD) are associated with poor prognosis in patients with acute myeloid leukemia (AML). Due to the development of drug resistance, few FLT3-ITD inhibitors are effective against FLT3-ITD+ AML. In this study, we show that FLT3-ITD activates a novel pathway involving p21Cdkn1a (p21) and pre-B cell leukemia transcription factor 1 (Pbx1) that attenuates FLT3-ITD cell proliferation and is involved in the development of drug resistance. FLT3-ITD up-regulated p21 expression in both mouse bone marrow c-kit+-Sca-1+-Lin- (KSL) cells and Ba/F3 cells. The loss of p21 expression enhanced growth factor-independent proliferation and sensitivity to cytarabine as a consequence of concomitantly enriching the S+G2/M phase population and significantly increasing the expression of Pbx1, but not Evi-1, in FLT3-ITD+ cells. This enhanced cell proliferation following the loss of p21 was partially abrogated when Pbx1 expression was silenced in FLT3-ITD+ primary bone marrow colony-forming cells and Ba/F3 cells. When FLT3-ITD was antagonized with AC220, a selective inhibitor of FLT3-ITD, p21 expression was decreased coincident with Pbx1 mRNA up-regulation and a rapid decline in the number of viable FLT3-ITD+ Ba/F3 cells; however, the cells eventually became refractory to AC220. Overexpressing p21 in FLT3-ITD+ Ba/F3 cells delayed the emergence of cells that were refractory to AC220, whereas p21 silencing accelerated their development. These data indicate that FLT3-ITD is capable of inhibiting FLT3-ITD+ cell proliferation through the p21/Pbx1 axis and that treatments that antagonize FLT3-ITD contribute to the subsequent development of cells that are refractory to a FLT3-ITD inhibitor by disrupting p21 expression.

Internal tandem duplication of FLT3 deregulates proliferation and differentiation and confers resistance to the FLT3 inhibitor AC220 by Up-regulating RUNX1 expression in hematopoietic cells.

Internal tandem duplication in the FLT3 gene (FLT3/ITD), which is found in patients with acute myeloid leukemia (AML), causes resistance to FLT3 inhibitors. We found that RUNX1, a transcription factor that regulates normal hematopoiesis, is up-regulated in patients with FLT3/ITD(+) AML. While RUNX1 can function as a tumor suppressor, recent data have shown that RUNX1 is required for AML cell survival. In the present study, we investigated the functional role of RUNX1 in FLT3/ITD signaling. FLT3/ITD induced growth factor-independent proliferation and impaired G-CSF mediated myeloid differentiation in 32D hematopoietic cells, coincident with up-regulation of RUNX1 expression. Silencing of RUNX1 expression significantly decreased proliferation and secondary colony formation, and partially abrogated the impaired myeloid differentiation of FLT3/ITD(+) 32D cells. Although the number of FLT3/ITD(+) 32D cells declined after incubation with the FLT3/ITD inhibitor AC220, the cells became refractory to AC220, concomitant with up-regulation of RUNX1. Silencing of RUNX1 abrogated the emergence and proliferation of AC220-resistant FLT3/ITD(+) 32D cells in the presence of AC220. Our data indicate that FLT3/ITD deregulates cell proliferation and differentiation and confers resistance to AC220 by up-regulating RUNX1 expression. These findings suggest an oncogenic role for RUNX1 in FLT3/ITD(+) cells and that inhibition of RUNX1 function represents a potential therapeutic strategy in patients with refractory FLT3/ITD(+) AML.

[Full Recovery from Cardiopulmonary Arrest caused by Traumatic Asphyxia].

Traumatic asphyxia is a crush injury of the chest characterized by facial edema, cyanosis, conjunctival hemorrhage, and petechiae on the face and chest. The prognosis depends on the duration of chest compression and early cardiopulmonary resuscitation after cardiopulmonary arrest. Here we report a case of full recovery from cardiopulmonary arrest caused by traumatic asphyxia. The chest of a 56-year-old man was compressed by a machine while working. Immediately, his colleague started cardiopulmonary resuscitation, which was successful. When he was admitted to our hospital, his consciousness level was E1V2M2(Glasgow coma scale). Our treatment included therapeutic hypothermia, the duration of which was 24 hours at 34 °C. Rewarming his body to 36 °C took place over 48 hours. Thereafter, he recovered completely and was discharged on the 12th hospital day without neurologic sequela. Therapeutic hypothermia was possibly effective in this case.

Ex Vivo Expanded Allogeneic Mesenchymal Stem Cells With Bone Marrow Transplantation Improved Osteogenesis in Infants With Severe Hypophosphatasia.

Patients with severe hypophosphatasia (HPP) develop osteogenic impairment with extremely low alkaline phosphatase (ALP) activity, resulting in a fatal course during infancy. Mesenchymal stem cells (MSCs) differentiate into various mesenchymal lineages, including bone and cartilage. The efficacy of allogeneic hematopoietic stem cell transplantation for congenital skeletal and storage disorders is limited, and therefore we focused on MSCs for the treatment of HPP. To determine the effect of MSCs on osteogenesis, we performed multiple infusions of ex vivo expanded allogeneic MSCs for two patients with severe HPP who had undergone bone marrow transplantation (BMT) from asymptomatic relatives harboring the heterozygous mutation. There were improvements in not only bone mineralization but also muscle mass, respiratory function, and mental development, resulting in the patients being alive at the age of 3. After the infusion of MSCs, chimerism analysis of the mesenchymal cell fraction isolated from bone marrow in the patients demonstrated that donor-derived DNA sequences existed. Adverse events of BMT were tolerated, whereas those of MSC infusion did not occur. However, restoration of ALP activity was limited, and normal bony architecture could not be achieved. Our data suggest that multiple MSC infusions, following BMT, were effective and brought about clinical benefits for patients with lethal HPP. Allogeneic MSC-based therapy would be useful for patients with other congenital bone diseases and tissue disorders if the curative strategy to restore clinically normal features, including bony architecture, can be established.

Internal tandem duplication mutations in FLT3 gene augment chemotaxis to Cxcl12 protein by blocking the down-regulation of the Rho-associated kinase via the Cxcl12/Cxcr4 signaling axis.

Internal tandem duplication mutations in the Flt3 gene (ITD-FLT3) enhance cell migration toward the chemokine Cxcl12, which is highly expressed in the therapy-protective bone marrow niche, providing a potential mechanism underlying the poor prognosis of ITD-FLT3(+) acute myeloid leukemia. We aimed to investigate the mechanisms linking ITD-FLT3 to increased cell migration toward Cxcl12. Classification of the expression of Cxcl12-regulated genes in ITD-FLT3(+) cells demonstrated that the enhanced migration of ITD-FLT3(+) cells toward Cxcl12 was associated with the differential expression of genes downstream of Cxcl12/Cxcr4, which are functionally distinct from those expressed in ITD-FLT3(-) cells but are independent of the Cxcr4 expression levels. Among these differentially regulated genes, the expression of Rock1 in the ITD-FLT3(+) cells that migrated toward Cxcl12 was significantly higher than in ITD-FLT3(-) cells that migrated toward Cxcl12. In ITD-FLT3(-) cells, Rock1 expression and Mypt1 phosphorylation were transiently up-regulated but were subsequently down-regulated by Cxcl12. In contrast, the presence of ITD-FLT3 blocked the Cxcl12-induced down-regulation of Rock1 and early Mypt1 dephosphorylation. Likewise, the FLT3 ligand counteracted the Cxcl12-induced down-regulation of Rock1 in ITD-FLT3(-) cells, which coincided with enhanced cell migration toward Cxcl12. Rock1 antagonists or Rock1 shRNA abolished the enhanced migration of ITD-FLT3(+) cells toward Cxcl12. Our findings demonstrate that ITD-FLT3 increases cell migration toward Cxcl12 by antagonizing the down-regulation of Rock1 expression. These findings suggest that the aberrant modulation of Rock1 expression and activity induced by ITD-FLT3 may enhance acute myeloid leukemia cell chemotaxis to the therapy-protective bone marrow niche, where Cxcl12 is abundantly expressed.