Clinical characteristics and COVID-19-related outcomes of immunocompromised patients receiving tixagevimab/cilgavimab pre-exposure prophylaxis in Japan.

OBJECTIVE: Tixagevimab/cilgavimab is a cocktail of two long-acting monoclonal antibodies approved for pre-exposure prophylaxis (PrEP) of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection (cause of coronavirus disease 2019 [COVID-19]) in immunocompromised (IC) or high-risk patients. We investigated the patient characteristics and clinical outcomes of IC patients administered tixagevimab/cilgavimab for PrEP in real-world use in Japan. METHODS: This observational study used anonymous secondary data from Real-World Data Co., Ltd. for IC patients aged ≥12 years administered tixagevimab/cilgavimab between September 2022 and September 2023. We analyzed the baseline characteristics and event-rates of COVID-19-related clinical outcomes within 6 months of administration. RESULTS: Data were analyzed for 397 IC patients. About half (53.4 %) were male and the median age was 71.0 (interquartile range 61.0, 77.0) years. Malignancy (97.2 %), cardiovascular disease (71.3 %), and diabetes (66.5 %) were frequent comorbidities. Systemic corticosteroids and immunosuppressants were prescribed to 87.4 % and 24.9 %, respectively. The two most common target clinical conditions were active therapy for hematologic malignancies (88.2 %) and treatment with B cell-depleting therapies (57.4 %). The event-rates per 100 person-months (95 % confidence interval; number) for medically attended COVID-19, COVID-19 hospitalization, in-hospital mortality due to COVID-19, and all-cause death were 4.14 (3.06-5.48; n = 49), 1.74 (1.09-2.64; n = 22), 0.07 (0.00-0.42; n = 1), and 0.60 (0.26-1.17; n = 8), respectively. CONCLUSION: This is the first report using a multicenter database to describe the clinical characteristics and COVID-19-related outcomes of IC patients administered with tixagevimab/cilgavimab in real-world settings in Japan. This cohort of IC patients who received tixagevimab/cilgavimab included many elderly patients with comorbidities.

Alterations in mRNA expression of myelin proteins in the sciatic nerves and brains of streptozotocin-induced diabetic rats.

Diabetic neuropathy is the most common complication of diabetes. We examined the levels and the mRNA expression of myelin proteins in the sciatic nerves and the brains of streptozotocin-induced diabetic rats. The diabetic rats exhibited a decrease in body weight, elevation of the blood glucose level and a decrease in motor nerve conduction velocity at 2 weeks after streptozotocin injection. In the sciatic nerves of diabetic rats, the level of P0 protein and its mRNA expression were markedly reduced at 20 weeks after the injection. In the brains, the levels of proteolipid protein and myelin-associated glycoprotein and their mRNA expression were selectively decreased at 20 weeks after the injection. This affected expression of myelin proteins was found even when no histological abnormalities were detectable. Considering the functional significance of myelin proteins, this impairment of protein expression is possibly involved in the pathogenesis of diabetic neuropathy, including that in brain disorders.

Caenorhabditis elegans opens up new insights into circadian clock mechanisms.

The roundworm, Caenorhabditis elegans, is known to carry homologues of clock genes such as per (=period) and tim (=timeless), which constitute the core of the circadian clock in Drosophila and mammals: lin-42 and tim-1. Analyses using WormBase (C. elegans gene database) have identified with relatively high identity analogous of the clock genes recognized in Drosophila and mammals, with the notable exception of cry (=cryptochrome), which is lacking in C. elegans. All of these C. elegans cognates of the clock genes appear to belong to members of the PAS-superfamily and to participate in development or responsiveness to the environment but apparently are not involved in the C. elegans circadian clock. Nevertheless, C. elegans exhibits convincing circadian rhythms in locomotor behavior in the adult stage and in resistance to hyperosmotic stress in starved larvae (L1) after hatching, indicating that it has a circadian clock with a core design entirely different from that of Drosophila and mammals. Here two possibilities are considered. First, the core of the C. elegans circadian clock includes transcriptional/translational feedback loops between genes and their protein products that are entirely different from those of Drosophila and mammals. Second, a more basic principle such as homeostasis governs the circadian cellular physiology, and was established primarily to minimize the accumulation of DNA damage in response to an environment cycling at 24 h intervals.

Chemical structures and immunolocalization of glycosphingolipids isolated from Diphyllobothrium hottai adult worms and plerocercoids.

Glycosphingolipids (GSLs) were purified from adults and plerocercoids of the tapeworm Diphyllobothrium hottai, and their chemical structures were determined. Total lipid fractions prepared from chloroform/methanol extracts of whole tissues were fractionated successively on ion-exchange chromatography, silicic acid column chromatography, and preparative TLC. The purified GSLs were characterized by methylation analysis, TLC-immunostaining, liquid secondary ion MS, MALDI-TOF MS, and 1H-NMR. Ten GSLs were isolated from adult worms and four from plerocercoids, comprising mono-, di-, tri-, tetra-, and pentasaccharides. The GSL Gal beta 1-4(Fuc alpha 1-3)Glc beta 1-3Gal beta 1-Cer was found in adult worms but not in plerocercoids, whereas Ga lbeta 1-4 (Fuc alpha 1-3)Glc beta 1-3(Gal beta 1-6)Gal beta 1-Cer was found in both adult worms and plerocercoids. We previously found a similar series of GSLs in plerocercoids of the cestode Spirometra erinaceieuropaei, and termed them 'spirometosides'[Kawakami, Y. et al. (1996) Eur J. Biochem. 239, 905-911]. The core structure of spirometosides, Gal beta 1-4Glc beta 1-3 Gal beta 1-Cer, may have taxonomic significance, being characteristic of pseudophyllidean tapeworms. In the present study, GSL compositions were significantly different between adults and plerocercoids, and growth-dependent changes in composition were documented. We found a novel dihexosylceramide, Glc beta 1-3Gal beta 1-Cer, which is a possible precursor for spirometosides. Immunohistochemical examination showed that spirometoside GSLs are highly enriched in the inner surface of bothria, the major point of contact between the adult worm and the host's intestine. Our findings indicate that spirometosides are involved in host-parasite interaction.