Clinically inapparent mpox virus (MPXV) infections among clients of three anonymous Community Based Voluntary Counselling and Testing centres in Berlin, Germany, 2022-2023.

Introduction: Since the mpox outbreak in 2022, it was unclear if and how often infections with mpox virus (MPXV) were clinically inapparent, i.e. not presenting to clinical care with mpox symptoms.

A Prospective, Randomized Trial Testing Different Regimens of Carbohydrate Administration to Prevent Major Reduction in Plasma Glucose Follwing a Standardized Bout of Moderate Physical Activity in Patients with Type 1 Diabetes.

Aim/hypothesis: It was the aim to prospectively study regimes of "preventive" carbohydrate administration to avoid major reduction in plasma glucose during physical activity.

Methods: 24 patients with type 1 diabetes (age 41±12 years; 11 women, 13 men; BMI 26.5±4.

Ganglioside Metabolism in Health and Disease.

Gangliosides (GGs) are cell type-specific sialic acid-containing glycosphingolipids (GSLs), which are enriched in mammalian brain. Defects in GSL metabolism cause fatal human diseases. GSLs are composed of a hydrophilic oligosaccharide linked in 1-O-position to a hydrophobic ceramide anchor, which itself is composed of a long-chain amino alcohol, the sphingoid base, and an amide-bound acyl chain.

Unbalanced lipolysis results in lipotoxicity and mitochondrial damage in peroxisome-deficient mutants.

Inherited peroxisomal biogenesis disorders (PBDs) are characterized by the absence of functional peroxisomes. They are caused by mutations of peroxisomal biogenesis factors encoded by genes, and result in childhood lethality. Owing to the many metabolic functions fulfilled by peroxisomes, PBD pathology is complex and incompletely understood.

Sphingolipids and lysosomal pathologies.

Endocytosed (glyco)sphingolipids are degraded, together with other membrane lipids in a stepwise fashion by endolysosomal enzymes with the help of small lipid binding proteins, the sphingolipid activator proteins (SAPs), at the surface of intraluminal lysosomal vesicles. Inherited defects in a sphingolipid-degrading enzyme or SAP cause the accumulation of the corresponding lipid substrates, including cytotoxic lysosphingolipids, such as galactosylsphingosine and glucosylsphingosine, and lead to a sphingolipidosis. Analysis of patients with prosaposin deficiency revealed the accumulation of intra-endolysosmal vesicles and membrane structures (IM).

Lysosomal lipid storage diseases.

Lysosomal lipid storage diseases, or lipidoses, are inherited metabolic disorders in which typically lipids accumulate in cells and tissues. Complex lipids, such as glycosphingolipids, are constitutively degraded within the endolysosomal system by soluble hydrolytic enzymes with the help of lipid binding proteins in a sequential manner. Because of a functionally impaired hydrolase or auxiliary protein, their lipid substrates cannot be degraded, accumulate in the lysosome, and slowly spread to other intracellular membranes.

Principles of lysosomal membrane degradation: Cellular topology and biochemistry of lysosomal lipid degradation.

Cellular membranes enter the lysosomal compartment by endocytosis, phagocytosis, or autophagy. Within the lysosomal compartment, membrane components of complex structure are degraded into their building blocks. These are able to leave the lysosome and can then be utilized for the resynthesis of complex molecules or can be further degraded.

Overexpression and mass spectrometry analysis of mature human acid ceramidase.

Human acid ceramidase catalyzes the last step of lysosomal sphingolipid degradation, the hydrolysis of ceramide to sphingosine and free fatty acid. Inherited deficiency of acid ceramidase activity leads to Farber disease (Farber lipogranulomatosis). In this study, we describe the overexpression and processing of recombinant human acid ceramidase in Sf21 insect cells, its purification and characterization.

Phosphatidylinositol-3,5-Bisphosphate is a potent and selective inhibitor of acid sphingomyelinase.

Acid sphingomyelinase (A-SMase, EC 3.1.4.

Purification and characterization of recombinant, human acid ceramidase. Catalytic reactions and interactions with acid sphingomyelinase.

Human acid ceramidase was overexpressed in Chinese hamster ovary cells by amplification of the transfected, full-length cDNA. The majority of the overexpressed enzyme was secreted into the culture media and purified to apparent homogeneity. The purified protein contained the same 13-(alpha) and 40 (beta)-kDa subunits as human acid ceramidase from natural sources, had an acidic pH optimum (4.