Kidney xenotransplantation has been attracting attention as a treatment option for end-stage renal disease. Fetal porcine kidneys are particularly promising grafts because they can reduce rejection through vascularization from host vessels. We are proposing xenogeneic regenerative medicine using fetal porcine kidneys injected with human nephron progenitor cells. For clinical application, it is desirable to establish reliable methods for the preservation and quality assessment of grafts. We evaluated the differentiation potency of vitrified porcine fetal kidneys compared with nonfrozen kidneys, using an in vivo differentiation model. Fetal porcine kidneys connected to the bladder were frozen via vitrification and stored in liquid nitrogen. Several days later, they were thawed and transplanted under the retroperitoneum of immunocompromised mice. After 14 days, the frozen kidneys grew and differentiated into mature nephrons, and the findings were comparable to those of nonfrozen kidneys. In conclusion, we demonstrated that the differentiation potency of vitrified fetal porcine kidneys could be evaluated using this model, thereby providing a practical protocol to assess the quality of individual lots.

No abstract

We present the characterization of a case with a small supernumerary marker chromosome (sSMC) detected prenatally derived from Xq28 and 14q11.2 maternal translocation. A 33-year-old Japanese woman, primigravida, underwent amniocentesis because of fetal growth restriction and fetal structural abnormality at 30 weeks of gestation. The fetal karyotype was identified as 47,XY,+mar. Additionally, the single nucleotide polymorphism array analysis revealed copy number gains at Xq28 and 14q11.2. A male infant, weighing 1,391 g, was delivered at term by cesarean section. Maternal and paternal karyotypes were 46,X,t(X; 14)(q28; q11) and 46,XY, respectively. These findings indicated that the sSMC might have originated from chromosome disjunction at a ratio of three to one. Here we describe a case with an sSMC derived from Xq28 and 14q11.2. Our findings suggest that this sSMC is most likely pathogenic. The collection of additional cases may be required.

Limited data are available on the effects of enteral sulfonylurea (SU) monotherapy in extremely low birth weight infants (ELBWIs) with hyperglycemia. Therefore, we report our experience with enteral SU monotherapy for hyperglycemic ELBWIs. We retrospectively evaluated 11 hyperglycemic ELBWIs (seven male infants, median gestational age = 24.9 wk) who received SU between January 2016 and December 2019. Blood glucose (BG) levels were monitored before and after SU initiation and evaluated for the occurrence of adverse effects.We administered SU at a median of 15 d (interquartile range [IQR]: 12-20 d) after birth, with the median maximum dose of 0.2 mg/kg/d (IQR: 0.125-0.3 mg/kg/d). Hyperglycemia improved in all patients, and the target BG levels were achieved without severe side effects at a median of 6 d (IQR: 4-8.5 d) after initiation of treatment. The incidence of hypoglycemia during SU treatment was observed in 18 events per 1000 patient hours; however, the patients were asymptomatic. Based on these results, enteral SU monotherapy may be considered as an option for hyperglycemic ELBWIs. Highlights• This is the first case series of SU treatment in hyperglycemic ELBWIs• SU can be helpful in decreasing blood glucose levels in hyperglycemic ELBWIs• Further studies are required to evaluate efficacy and safety of SU in ELBWIs

No abstract