Diamine oxidase knockout mice are not hypersensitive to orally or subcutaneously administered histamine.

Objective: To evaluate the contribution of endogenous diamine oxidase (DAO) in the inactivation of exogenous histamine, to find a mouse strain with increased histamine sensitivity and to test the efficacy of rhDAO in a histamine challenge model.

Methods: Diamine oxidase knockout (KO) mice were challenged with orally and subcutaneously administered histamine in combination with the β-adrenergic blocker propranolol, with the two histamine-N-methyltransferase (HNMT) inhibitors metoprine and tacrine, with folic acid to mimic acute kidney injury and treated with recombinant human DAO. Core body temperature was measured using a subcutaneously implanted microchip and histamine plasma levels were quantified using a homogeneous time resolved fluorescence assay.

Treatment of legionellosis including a single intravenous dose of 1.5 g azithromycin: 18-year experience at a tertiary care hospital.

Objectives: Due to recent safety concerns regarding fluoroquinolones and the potential medical and economic benefits, we investigated the efficacy of a single intravenous dose of 1.5 g azithromycin for the treatment of pulmonary legionellosis.

Methods: Using a nationwide legionellosis registry for pre-selection, 74 patients admitted from 2000-2018 to a tertiary care hospital owing to pneumonia caused by Legionella pneumophila were retrospectively included in this study.

Comparison of non-invasive Staphylococcus aureus sampling methods on lesional skin in patients with atopic dermatitis.

There is evidence that Staphylococcus aureus colonisation is linked to severity of atopic dermatitis. As no gold standard for S. aureus sampling on atopic dermatitis skin lesions exists, this study compared three commonly used methods.

Postoperative complications and waiting time for surgical intervention after radiologically guided drainage of intra-abdominal abscess in patients with Crohn's disease.

Background: In patients with active Crohn's disease (CD), treatment of intra-abdominal abscess usually comprises antibiotics and radiologically guided percutaneous drainage (PD) preceding surgery. The aim of this study was to investigate the risk of postoperative complications and identify the optimal time interval for surgical intervention after PD.

Methods: A multicentre, international, retrospective cohort study was carried out.

Extracellular Vesicles and Citrullinated Histone H3 in Coronavirus Disease 2019 Patients.

Objectives: Pulmonary thrombus formation is a hallmark of coronavirus disease 2019 (COVID-19). A dysregulated immune response culminating in thromboinflammation has been described, but the pathomechanisms remain unclear.

Methods: We studied 41 adult COVID-19 patients with positive results on reverse-transcriptase polymerase-chain-reaction assays and 37 sex- and age-matched healthy controls.

Synergistic Effect of Cefazolin Plus Fosfomycin Against and in an Experimental Model.

This study investigated the synergistic and activity of cefazolin plus fosfomycin against methicillin-susceptible and methicillin-resistant (MSSA and MRSA) to provide the basis for a potential treatment alternative. Antimicrobial susceptibility and synergy tests were performed with five MSSA and five MRSA isolates using the broth microdilution and chequerboard assays, respectively. The efficacy of cefazolin plus fosfomycin for the treatment of MRSA infections was assessed using the survival assay.

A Longitudinal Seroprevalence Study Evaluating Infection Control and Prevention Strategies at a Large Tertiary Care Center with Low COVID-19 Incidence.

Personal protective equipment and adherence to disinfection protocols are essential to prevent nosocomial severe acute respiratory syndrome coronavirus (SARS-CoV-2) transmission. Here, we evaluated infection control measures in a prospective longitudinal single-center study at the Vienna General Hospital, the biggest tertiary care center in Austria, with a structurally planned low SARS-CoV-2 exposure. SARS-CoV-2-specific antibodies were assessed by Abbott ARCHITECT chemiluminescent assay (CLIA) in 599 health care workers (HCWs) at the start of the SARS-CoV-2 epidemic in early April and two months later.

Human diamine oxidase is readily released from activated neutrophils ex vivo and in vivo but is rarely elevated in bacteremic patients.

During human diamine oxidase (DAO) ELISA development we noticed that in serum DAO concentrations appear to be higher when compared to plasma. Neutrophils contain DAO in the specific granules and we hypothesized that DAO is released from neutrophils during serum coagulation. If activation of neutrophils can release DAO, its concentrations might be elevated in vivo after lipopolysaccharide (LPS) administration and in bacteremic patients.

Different Types of Coagulase Are Associated With 28-Day Mortality in Patients With Bloodstream Infections.

, a leading cause of bacteremia and infective endocarditis, exploits the human coagulation system by using a wide range of specific virulence factors. However, the impact of these host-pathogen interactions on the outcome of patients with bacteremia (SAB) remains unclear. A total of 178 patients with bacteremia were included and analyzed regarding bacterial factors ( gene size, and clinical parameters.

Simple, sensitive and specific quantification of diamine oxidase activity in complex matrices using newly discovered fluorophores derived from natural substrates.

Objective: To measure diamine oxidase (DAO) activity with high sensitivity in complex matrices like plasma or tissue extracts radioactive putrescine or horseradish peroxidase (HRP)/hydrogen peroxide (HO) coupling must be used. The use of radioactive material should be avoided and HRP/HO coupling is compromised by antioxidants.

Methods And Results: Condensation of ortho-aminobenzaldehyde (oABA) with delta-1-pyrroline and delta-1-piperideine, the autocyclization products of the DAO-oxidized natural substrates putrescine and cadaverine, generates new quinazoline fluorophores with absorption and excitation maxima of 430 and 460 nm, respectively, and peak emission at 620 nm.

Emergence of a dalbavancin induced glycopeptide/lipoglycopeptide non-susceptible Staphylococcus aureus during treatment of a cardiac device-related endocarditis.

In the present study, we demonstrated the emergence of dalbavancin non-susceptible and teicoplanin-resistant Staphylococcus aureus small colony variants which were selected in vivo through long-term treatment with dalbavancin. A 36-year-old man presented with a cardiac device-related S. aureus endocarditis and received long-term therapy with dalbavancin.

Hepatocyte specific expression of an oncogenic variant of β-catenin results in cholestatic liver disease.

Background: The Wnt/β-catenin signaling pathway plays a crucial role in embryonic development, tissue homeostasis, wound healing and malignant transformation in different organs including the liver. The consequences of continuous β-catenin signaling in hepatocytes remain elusive.

Results: Livers of Ctnnb1CA hep mice were characterized by disturbed liver architecture, proliferating cholangiocytes and biliary type of fibrosis.