Legionella pneumophila Evades Gamma Interferon-Mediated Growth Suppression through Interleukin-10 Induction in Bone Marrow-Derived Macrophages

We examined the roles of Th1-Th2 cytokine cross talk in Legionella pneumophila-infected bone marrow-derived (BM) macrophages in the presence of costimulation with interleukin-12 (IL-12) and IL-18. Treatment with gamma interferon (IFN-γ) alone or treatment with IL-12 in combination with IL-18 resulted in a 3- or 2-log reduction in bacterial numbers, respectively, in BM macrophages, whereas treatment with IL-12 or IL-18 alone had no effect. Significant amounts of IFN-γ were detected in the culture supernatants of infected macrophages stimulated with IL-12 and IL-18 in combination but not independently. Neutralization of IFN-γ by antibody completely abolished the growth inhibitory effects of IL-12 and IL-18. Interestingly, higher infectivity ratios of L. pneumophila or the addition of increasing concentrations of heat-killed bacteria (HKB) suppressed the production of IFN-γ, which resulted in the increased intracellular growth of bacteria. Significant amounts of IL-10 were detected in culture supernatants when Legionella-infected macrophages were cocultured with HKB. Furthermore, neutralization of IL-10 by antibody resulted in an increase in IFN-γ production by infected BM macrophages when cocultured with HKB. Treatment of HKB with trypsin but not polymyxin B attenuated the growth-promoting effects of HKB, suggesting the involvement of a protein component(s) in regulation of the growth of L. pneumophila. These findings demonstrate a crucial role of Th1-Th2 cross talk in L. pneumophila-infected BM macrophages. Our results also suggest that L. pneumophila modulates the cytokine balance from IFN-γ-driven Th1 to more Th2 responses, likely through the induction of IL-10 by a bacterial protein component(s). These data provide new insights not only into the cellular mechanisms of Th1-Th2 cross talk in Legionella-infected macrophages but also into the pathogenesis of L. pneumophila pneumonia in humans

Spirituality, Quality of Life, and Health: A Japanese Cross-Sectional Study

Background: Current reports suggest a positive association between spirituality and quality of life (QoL) in elders. While most studies are qualitative studies and there has been little validation in quantitative studies using scales to measure spirituality. Hence, we aimed to study the effect of spirituality on mental health and QoL in older people residing in Kumejima Town in Japan. Methods: An interview-based survey was conducted between September 2010 and 2011 on residents of Kumejima Town aged 65 years or older. This survey-based study employed the Spirituality Health Scale for the Elderly (SP Health Scale) alongside assessments of basic attributes (e.g., age, sex); physical, mental, social health, spirituality, and QoL. We conducted a causal structure model to explore causal relationships between these factors. Results: Our study included 338 participants, including 72.5% female with an average age and standard deviation of 77.2 ± 6.4 years. Our analysis revealed a significant association between spiritual health and QoL even after accounting for the impact of physical and mental health, which challenged the conventional belief that QoL inevitably diminishes with age and declining health. These results suggest that enhancing spirituality may offer a means to prevent declines in QoL, fostering a positive outlook on life as individuals age. Conclusion: Our study suggests that improving spiritual health can enhance QoL, even in the presence of health challenges and aging. This novel perspective opens doors to redefining health as a state that coexists with illness, with spirituality serving as an integral component. A shift in our understanding of health that prioritizes spirituality, could benefit people of all ages, offering a more holistic approach to well-being that aligns with new medical technologies and evolving perceptions of health

Pseudomonas otitidis bacteremia in an immunocompromised patient with cellulitis: case report and literature review

Abstract Background Pseudomonas otitidis belongs to the genus Pseudomonas and causes various infections, including ear, skin, and soft tissue infections. P. otitidis has a unique susceptibility profile, being susceptible to penicillins and cephalosporins but resistant to carbapenems, due to the production of the metallo-β-lactamase called POM-1. This revealed genetic similarities with Pseudomonas aeruginosa, which can sometimes lead to misidentification. Case presentation We report the case of a 70-year-old Japanese male who developed cellulitis and bacteremia during chemotherapy for multiple myeloma. He was initially treated with meropenem, but blood culture later revealed gram-negative bacilli identified as P. otitidis using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Carbapenem resistance was predicted from previous reports; therefore, we switched to dual therapy with levofloxacin and cefepime, and favorable treatment results were obtained. Conclusion This is the first reported case of P. otitidis cellulitis and bacteremia in an immunocompromised patient. Carbapenems are typically used in immunocompromised patients and P. otitidis is often resistant to it. However, its biochemical properties are similar to those of Pseudomonas aeruginosa; therefore, its accurate identification is critical. In the present study, we rapidly identified P. otitidis using MALDI-TOF MS and switched from carbapenems to an appropriate antimicrobial therapy, resulting in a successful outcome