D-Aspartic acid (D-Asp) was found in a high content in a-crystallin isolated from the watersoluble fraction of aged human lens. a-Crystallin was separated to o:A-and aB-crystallins by reverse-phase chromatography. Racemization of aspartic acid proceeded to a larger extent in 01A-crystallin than in aB-crystallin. Purified aA-crystallin was treated with trypsin to yield peptides that were then separated by HPLC using a C18 column. Tryptic peptides of 0:A-crystallin were separated and analyzed for amino acid composition and racemization of aspartic acid. Each aspartyl and asparginyl residue in the protein was racemized to a different extent. Aspss (D/L ratio of Asp, 1.41) and Aspm (3.04) were highly racemized. The D/L ratio of other aspartyl residues ranged from 0.1 to 0.2.The biologically uncommon D-aspartyl residues have been found in long-lived proteins, such as tooth (9) and eye lens (4-6, 13-15, 18) of aged mammals. Aspartic acid (Asp) is the most easily racemizable amino acid (1), and it has been considered that D-aspartic acid (D-Asp) may be formedby racemization in the metabolically inactive tissues during the natural aging process. In the lens protein, D-Asp has been found only in the water-insoluble fraction of aged lens (4-6, 13-15). We have isolated a D-Asp-containing protein from the waterinsoluble fraction of bovine adult lens (4) and confirmed that the origin of this protein was aAcrystallin from the water-soluble fraction (15). It was considered that the water-soluble 0cA-crystallin had been converted to a water-insoluble fraction with aggregation and racemization during aging. aA-Crystallin is the major component of lens protein and its function is related to maintenance of transparency of the lens (2). If the racemization of Asp occurred in aA-crystallin, the higher structure and the function of the protein would be affected. Therefore, as the next step of our studies, we have directed our attention to the racemization of Asp in o:A-crystallin in the water-soluble fraction from As an extension of our previous study (15), we have clarified in the present experiment that racemization occurs predominantly in the watersoluble aA-crystallin and that the extent of racemization of Asp at two specific sites of 01A-crystallin is extremely high. MATERIALS AND METHODS Purification of 0cA-czysraliin from Human LensForty aged human (about 80 years old) lenses were homogenized in 2 mM 2-mercaptoethanol/35 mM Tris-HCl buffer (pH 7.4). The proteins were fractionated into water-soluble and water-insoluble fractions by centrifugation at 20,000 g for 60 min at 4°C. The water-soluble fraction was dialyzed against 0.1 M Tris-HC1 buffer (pH 7.4) and was fractionated by DEAE-Toyopearl column equilibrated with the same buffer. The elution was car-

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Background Coronavirus Disease 2019-associated pulmonary aspergillosis (CAPA) is a fatal complication in the general population. However, there are few reports on CAPA in patients undergoing hemodialysis (HD). Methods This retrospective observational cohort study was conducted at a single center between December 2020 and June 2021. We enrolled 21 HD patients with Coronavirus Disease 2019 (COVID-19) undergoing treatment and divided them into two groups: CAPA and non-CAPA (COVID-19 with and without pulmonary aspergillosis); we evaluated their characteristics, clinical outcomes, and comorbidities. Results The log-rank test revealed that the 90-day survival rate after the initiation of treatment for COVID-19 was significantly lower in the CAPA (n = 6) than in the non-CAPA group (n = 15) (P = 0.0002), and the 90-day mortality rates were 66.6% and 0% in the CAPA and non-CAPA groups, respectively. In the CAPA group, four patients died due to respiratory failure (on days 6 and 20), gastrointestinal bleeding (day 8), and sepsis (day 33); the RT-PCR for SARS-CoV-2 remained positive when they died. The remaining two patients survived, and the negative conversion of RT-PCR for SARS-CoV-2 was confirmed on days 10 and 15. The negative conversion of serum (1, 3)-β-D-glucan (BDG) was confirmed on day 15 in one patient; the BDG remained positive on day 64 in the other. Conclusions CAPA is a fatal complication in HD patients and the general population. Therefore, clinicians should consider the possibility of testing for CAPA in patients undergoing hemodialysis. Mycological workups may be helpful for the early detection of CAPA.

Amino acids recovered from fossil egg shells of dinosaurs showed two kinds. One is antique and small in amount showing the D/L ratio nearly one. The other is more abundant and seems Recent in origin. The antique ones might be residue of peptides at the shell formation.