Search

Staphylococcus aureus is a highly successful pathogen infecting various body parts and forming biofilms on natural and artificial surfaces resulting in difficult-to-treat and chronic infections. We investigated the secreted cytokines and proteomes of isolated peripheral blood mononuclear cells (PBMCs) from healthy volunteers exposed to methicillin-resistant S. aureus (MRSA) biofilms or planktonic bacteria. Additionally, the cytokine profiles in sera from patients with community-acquired pneumonia (CAP) caused by S. aureus were investigated. The aim was to gain insights into the immune response involved and differentiate between the planktonic and sessile MRSA forms. We identified 321 and 298 targets that were significantly differently expressed in PBMCs when exposed to planktonic or biofilm-embedded bacteria, respectively. PBMCs exposed to planktonic MRSA cells secreted increased levels of TNF-a, while IL-18 was elevated when exposed to the biofilm. The machine-learning analyses of the cytokine profiles obtained for the in vitro PBMCs and CAP sera distinguished between the two types of bacteria forms based on cytokines IL-18, IL12, and IL-17, and with a lower importance IL-6. Particularly, IL-18 which has not been correlated with S. aureus biofilms so far might represent a suitable marker for monitoring chronification during MRSA infection to individualize the therapy, but this hypothesis must be proved in clinical trials. [ABSTRACT FROM AUTHOR]

Background: The new ICD-11 diagnosis of prolonged grief disorder (PGD) is characterized by the prominent role of yearning as hallmark symptom. A secondary analysis of eight international datasets on PGD was conducted to evaluate this assumption. Additionally, cross-cultural comparison explored whether the centrality of yearning differs across world regions. Methods: Primary studies originated from German-speaking countries (n = 4 samples), other European countries and Israel (n = 3 samples), as well as China (n = 1 samples). Different PGD measures were used, including yearning and longing as symptoms. For the centrality assessment of yearning, PGD symptoms were ranked by their factor loadings from confirmatory factor analyses, followed by statistical testing to determine significant differences between yearning and other symptoms of PGD in their factor loading estimates. Subsequently, ranking positions of yearning in three world regions (German-speaking, other Europe-Israel, and China) were compared. Finally, proxy thresholds for individuals at high-risk states for PGD were defined for the different datasets, and sensitivity-specificity analyses of yearning were performed. Results: Yearning was ranked high in five out of 12 models tested. In the German-speaking region, it was predominantly ranked among the most central symptoms; in the other Europe-Israel region as well as China, it tended to fall into the middle or lower rankings of symptom centrality. Sensitivity values were consistently high, while specificity values indicated moderate levels. Discussion: In line with previous research on the general outcomes of grief, the present study showed that yearning may be subject to a culture-specific distribution. Other central symptoms such as feeling as if a part of oneself died have also been shown to potentially play a central role in PGD across world regions. On the other hand, the sensitivity-specificity analyses revealed that yearning can be considered a significant (diagnostically highly sensitive) symptom for individuals in high-risk states for PGD, although it has only moderate specificity (i.e., its absence does not necessarily indicate individuals experiencing normative grief). Nonetheless, a culture-sensitive approach to psychopathology should consider the cultural differences in the centrality of this symptom group. More research is needed to better understand the role of yearning and its determinants across world regions. [ABSTRACT FROM AUTHOR]