Clinical guidelines for the diagnosis and treatment of 21-hydroxylase deficiency (2021 revision).

Congenital adrenal hyperplasia is a category of disorders characterized by impaired adrenocortical steroidogenesis. The most frequent disorder of congenital adrenal hyperplasia is 21-hydroxylase deficiency, which is caused by pathogenic variants of and is prevalent between 1 in 18,000 and 20,000 in Japan. The clinical guidelines for 21-hydroxylase deficiency in Japan have been revised twice since a diagnostic handbook in Japan was published in 1989.

The Acylcarnitine Profile in Dried Blood Spots is Affected by Hematocrit: A Study of Newborn Screening Samples in Very-Low-Birth-Weight Infants.

Objective: The acylcarnitine profile is analyzed in dried blood spots (DBS) to screen for inborn errors of metabolism. Hematocrit (Ht) is known to affect the result of quantitative analyses of DBS samples; however, the effects of Ht on the acylcarnitine profiles in DBS have not been studied in actual samples from newborns.

Study Design: The acylcarnitine profiles in DBS for newborn screening tests and Ht levels of very-low-birth-weight infants were obtained from medical records.

Efficient syntheses of [2-(15)N]guanosine and 2'-deoxy[2-(15)N]guanosine derivatives.

Nucleophilic substitution of 9-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)-6-chloro-2-fluoro-9H-purine, prepared from guanosine, with N-tert-butyldimethylsilyl[(15)N]-phthalimide in the presence of a catalytic amount of CsF at room temperature in DMF efficiently afforded the 6-chloro-2-[(15)N]phthalimidopurine derivative. Treatment of this with sodium 2-cyanoethoxide yielded the [2-(15)N]guanosine derivative. The 2'-deoxy[2-(15)N]guanosine derivative was also efficiently synthesized through a similar procedure.

Efficient synthesis of [2-15N]guanosine and 2'-deoxy[2'-15N]guanosine derivatives using N-(tert-butyldimethylsilyl)[15N]phthalimide as a 15N-labeling reagent.

Nucleophilic aromatic substitution of 9-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)-6-chloro-2-fluoro-9H-purine with N-(tert-butyldimethylsilyl) [15N]phthalimide in the presence of a catalytic amount of CsF at room temperature in DMF efficiently afforded the 6-chloro-2-[15N]phthalimidopurine derivative, which was subsequently converted to the [2-15N]guanosine derivative. The 2'-deoxy[2'-15N]guanosine derivative was also efficiently synthesized through a similar procedure.