Evaluation of circulating IgG antibodies against Porphyromonas gingivalis or its gingipains as serological markers of periodontitis and carriage of the bacterium.

Background: Increasing evidence indicates that periodontitis contributes to systemic low-grade inflammation. Porphyromonas gingivalis is strongly associated with periodontitis, and antibodies against the bacterium may be used as a serological proxy to account for periodontal status, when studying diseases associated with periodontitis. The aim of the present study is to identify an easily accessible and reliable serological biomarker for determination of periodontal status and oral carriage of the bacterium.

Bacterial aerobic respiration is a major consumer of oxygen in sputum from patients with acute lower respiratory tract infection.

Bacterial aerobic respiration may determine the outcome of antibiotic treatment in experimental settings, but the clinical relevance of bacterial aerobic respiration for the outcome of antibiotic treatment has not been tested. Therefore, we hypothesized that bacterial aerobic respiration is higher in sputum from patients with acute lower respiratory tract infections (aLRTI), than in sputum from patients with chronic LRTI (cLRTI), where the bacteria persist despite antibiotic treatment. The bacterial aerobic respiration was determined according to the dynamics of the oxygen (O) concentration in sputum from aLRTI patients (n = 52).

Antimicrobial resistance of Pseudomonas aeruginosa in a cystic fibrosis population after introduction of a novel cephalosporin/β-lactamase inhibitor combination.

Ceftolozane-tazobactam is a new β-lactam/β-lactamase inhibitor combination approved by the U.S. Food and Drug Administration in 2019 for the treatment of hospital-acquired and ventilator-associated pneumonia.

"The Standard Procedure" for Investigation of Oral Neutrophils in Oral Diseases.

Aim: There is need of an objective "standard procedure" that is reliable and clinically applicable for estimating oral neutrophil content in relation to oral diseases.

Methods: Forty-one patients with suspected oral candidosis (OC) and nine healthy controls with no oral mucosal disease were flushing with 10 ml mouth rinse (MR) (sterile phosphate-buffered saline) for 1 min. Aliquots were stored on different conditions to explore stability, storage, and fixation conditions for analysis by flow cytometry.

3D blood-brain barrier-organoids as a model for Lyme neuroborreliosis highlighting genospecies dependent organotropism.

Lyme neuroborreliosis (LNB), a tick-borne infection caused by spirochetes within the sensu lato (s.L.) complex, is among the most prevalent bacterial central nervous system (CNS) infections in Europe and the US.

Hyperbaric oxygen therapy augments ciprofloxacin effect against biofilm infected chronic wounds in a mouse model.

Introduction: Chronic wounds have a compromised microcirculation which leads to restricted gas exchange. The majority of these hypoxic wounds is infested with microorganisms congregating in biofilms which further hinders the antibiotic function. We speculate whether this process can be counteracted by hyperbaric oxygen therapy (HBOT).

Prevalence of biofilms in acute infections challenges a longstanding paradigm.

The significance of bacterial biofilm formation in chronic bacterial lung infections has long been recognized [1]. Likewise, chronic biofilm formation on medical devices is well accepted as a nidus for recurrent bacteremia [2,3]. Even though the prevailing paradigm relies on the dominance of planktonic bacteria in acute endobronchial infections, our understanding of the bacterial organization during acute infection is, so far, limited - virtually absent.

A novel Borrelia-specific real-time PCR assay is not suitable for diagnosing Lyme neuroborreliosis.

Background: Diagnosing Lyme neuroborreliosis (LNB) is complicated by a lack of adequate test systems and by the complex culturing conditions required to grow the causative pathogens in the Borrelia sensu lato complex. Improved testing methods are urgently needed. Here, we evaluate the applicability of a novel commercially available Borrelia-specific real-time PCR assay to diagnose LNB.

Increased sputum lactate during oral glucose tolerance test in cystic fibrosis.

Blood glucose levels exceeding 8 mM are shown to increase glucose levels in airway surface in cystic fibrosis (CF). Moreover, high levels of endobronchial glucose are proposed to increase the growth of common CF bacteria and feed the neutrophil-driven inflammation. In the infected airways, glucose may be metabolized by glycolysis to lactate by both bacteria and neutrophils.

Adaptive Immune Response to Complex (MABSC) in Cystic Fibrosis and the Implications of Cross-Reactivity.

Background: We aimed to characterise the adaptive immune response to complex (MABSC) and its cross-reactivity with complex (MAC) and (Bacille Calmette-Guérin, BCG) in cystic fibrosis (CF) patients and non-CF controls in terms of lymphocyte proliferation and immunophenotyping, cytokine production and anti-MABSC IgG plasma levels.

Methods: In this cross-sectional analysis, peripheral blood mononuclear cells (PBMC) from CF patients with MABSC (CF/MABSC, n=12), MAC infection history (CF/MAC, n=5), no NTM history (CF/NTM-, n=15), BCG-vaccinated (C/BCG+, n=9) and non-vaccinated controls (C/BCG-, n=8) were cultured for four days under stimulation with an in-house MABSC lysate and we used flow cytometry to assess lymphocyte proliferation (given by lymphoblast formation) and immunophenotypes. Cytokine production was assessed after overnight whole blood stimulation with the same lysate, and anti-MABSC IgG levels were measured in plasma from non-stimulated blood.

The structure-function relationship of Pseudomonas aeruginosa in infections and its influence on the microenvironment.

Pseudomonas aeruginosa is a human pathogen associated with both acute and chronic infections. While intensively studied, the basic mechanisms enabling the long-term survival of P. aeruginosa in the host, despite massive immune system attack and heavy antimicrobial treatment, remain to be identified.

Endotracheal lactate reflects lower respiratory tract infections and inflammation in intubated patients.

The aim of this study was to assess L-lactate and D-lactate in endotracheal aspirate from intubated patients hospitalized at the intensive care unit and explore their use as diagnostic biomarkers for inflammation and lower respiratory tract infections (LRTI). Tracheal aspirates from 91 intubated patients were obtained at time of intubation and sent for microbiological analyses, neutrophil count, and colorimetric lactate measurements. We compared the concentration of lactate from patients with microbiological verified LRTI or clinical/radiological suspicion of LRTI with a control group.

Tolerance and resistance of microbial biofilms.

Chronic infections caused by microbial biofilms represent an important clinical challenge. The recalcitrance of microbial biofilms to antimicrobials and to the immune system is a major cause of persistence and clinical recurrence of these infections. In this Review, we present the extent of the clinical problem, and the mechanisms underlying the tolerance of biofilms to antibiotics and to host responses.

Bacterial biofilms predominate in both acute and chronic human lung infections.

Background: A basic paradigm of human infection is that acute bacterial disease is caused by fast growing planktonic bacteria while chronic infections are caused by slow-growing, aggregated bacteria, a phenomenon known as a biofilm. For lung infections, this paradigm has been thought to be supported by observations of how bacteria proliferate in well-established growth media in the laboratory-the gold standard of microbiology.

Objective: To investigate the bacterial architecture in sputum from patients with acute and chronic lung infections.

Nitric-oxide-driven oxygen release in anoxic .

Denitrification supports anoxic growth of in infections. Moreover, denitrification may provide oxygen (O) resulting from dismutation of the denitrification intermediate nitric oxide (NO) as seen in . To examine the prevalence of NO dismutation we studied O release by in airtight vials.

Distinct contribution of hyperbaric oxygen therapy to human neutrophil function and antibiotic efficacy against Staphylococcus aureus.

Staphylococcus aureus (SA) causes superficial and severe endovascular infections. The present in vitro study investigates the anti-SA mechanisms of hyperbaric oxygen therapy (HBOT) on direct bacterial killing, antibiotic potentiation, and polymorphonuclear leukocyte (PMN) enhancement. SA was exposed to isolated human PMNs, tobramycin, ciprofloxacin, or benzylpenicillin.

Animal models of chronic and recurrent Pseudomonas aeruginosa lung infection: significance of macrolide treatment.

Animal models of human diseases are invaluable and inevitable elements in identifying and testing novel treatments for serious diseases, including severe infections. Planning and conducting investigator-initiated human trials are generally accepted as being enormously challenging. In contrast, it is often underestimated how much planning, including background and modifying experiments, is needed to establish a relevant infectious disease animal model.

Hyperbaric oxygen treatment impacts oxidative stress markers in patients with necrotizing soft-tissue infection.

Necrotizing soft-tissue infection (NSTI) is a rare, severe, and fast-progressing bacterial infection associated with a high risk of developing sepsis or septic shock. Increasing evidence indicates that oxidative stress is crucial in the development and progression of sepsis, but its role in NSTI specifically has not been investigated. Some patients with NSTI receive hyperbaric oxygen (HBO) treatment as the restoration of oxidative stress balance is considered an important mechanism of action, which HBO facilitates.

Catalase Protects Biofilm of against Daptomycin Activity.

Daptomycin is recommended for the treatment of infections due to its bactericidal activity. However, its mechanism of action is poorly understood. The involvement of reactive oxygen species (ROS) in the bactericidal activity of daptomycin has been proved against planktonic , but not against the biofilm of .

Immune Responses to Biofilm Infections.

is a key pathogen of chronic infections in the lungs of cystic fibrosis patients and in patients suffering from chronic wounds of diverse etiology. In these infections the bacteria congregate in biofilms and cannot be eradicated by standard antibiotic treatment or host immune responses. The persistent biofilms induce a hyper inflammatory state that results in collateral damage of the adjacent host tissue.