Preoperative fibrinogen level predicts the risk and prognosis of patients with native valve infective endocarditis undergoing valve surgery.

Aim: The aim of this study was to assess the clinical significance and prognostic value of the preoperative fibrinogen (FBG) level in patients with native valve infective endocarditis (NVIE) who underwent valve surgery.

Methods: This retrospective study included a total of 163 consecutive patients who were diagnosed with NVIE and underwent valve surgery from January 2019 to January 2022 in our hospital. The primary endpoint was all-cause mortality.

Alkaline shock protein 23 (Asp23)-controlled cell wall imbalance promotes membrane vesicle biogenesis in Staphylococcus aureus.

Membrane vesicles (MVs) are produced by species across all domains of life and have diverse physiological functions as well as promising applications. While the mechanisms for vesiculation in Gram-negative bacteria are well-established, the genetic determinants and regulatory factors responsible for MV biogenesis in Gram-positive bacteria remain largely unknown. Here, we demonstrate that a Q225P substitution in the alternative sigma factor B (SigB) triggers MV production in Staphylococcus aureus strain Newman by hindering the specific binding of SigB to the asp23 promoter, thereby repressing expression of alkaline shock protein 23 (Asp23).

Unraveling the mechanism of thermotolerance by Set302 in .

The underlying mechanism of thermotolerance, which is a key virulence factor essential for pathogenic fungi such as , is largely unexplored. In this study, our findings suggest that Set302, a homolog of Set3 and a subunit of histone deacetylase complex Set3C, contributes to thermotolerance in . Specifically, the deletion of the predicted Set3C core subunit, Set302, resulted in further reduction in the growth of at 39°C, and survival of transient incubation at 50°C.

Hcp1-loaded staphylococcal membrane vesicle vaccine protects against acute melioidosis.

is the causal agent of melioidosis, a deadly tropical infectious disease that lacks a vaccine. On the basis of the attenuated RN4220-Δ (RN), we engineered the RN4220-Δ/ strain (RN-Hcp1) to generate hemolysin-coregulated protein 1 (Hcp1)-loaded membrane vesicles (MVs). The immunization of BALB/c mice with MVs mixed with adjuvant by a three-dose regimen increased the serum specific IgG production.

CcpA Regulates Biofilm Formation through Direct Repression of Staphylokinase Expression.

represents a notorious opportunistic pathogen causing various infections in biofilm nature, imposing remarkable therapeutic challenges worldwide. The catabolite control protein A (CcpA), a major regulator of carbon catabolite repression (CCR), has been recognized to modulate biofilm formation, while the underlying mechanism remains to be fully elucidated. In this study, the reduced biofilm was firstly determined in the deletion mutant of clinical isolate XN108 using both crystal violet staining and confocal laser scanning microscopy.

Essential Fitness Repertoire of Staphylococcus aureus during Co-infection with Acinetobacter baumannii .

Staphylococcus aureus represents a major human pathogen that is frequently involved in polymicrobial infections. However, the prevalence and role of co-infectious microbes on the pathogenesis and fitness essentiality of S. aureus remain largely unknown.

The Q225P Mutation in SigB Promotes Membrane Vesicle Formation in Staphylococcus aureus.

Both Gram-positive and Gram-negative bacteria release nano-sized lipid bilayered particles, known as membrane vesicles (MVs), into external environments. Although MVs play a variety of roles in bacterial physiology and pathogenesis, the mechanisms underlying MV formation in Gram-positive microorganisms such as Staphylococcus aureus remain obscure. Bacterial MV production can be induced in response to stress conditions, and the alternative sigma factor B (SigB) functions as a central regulator of the stress response in Gram-positive bacteria.

Engineered Remolding and Application of Bacterial Membrane Vesicles.

Bacterial membrane vesicles (MVs) are produced by both Gram-positive and Gram-negative bacteria during growth and . MVs are nanoscale vesicular structures with diameters ranging from 20 to 400 nm. MVs incorporate bacterial lipids, proteins, and often nucleic acids, and can effectively stimulate host immune response against bacterial infections.

Loss of Gsα impairs liver regeneration through a defect in the crosstalk between cAMP and growth factor signaling.

Background & Aims: The stimulatory G protein α subunit (Gsα) activates the cAMP-dependent pathway by stimulating the production of cAMP and participates in diverse cell processes. Aberrant expression of Gsα results in various pathophysiological disorders, including tumorigenesis, but little is known about its role in liver regeneration.

Methods: We generated a hepatocyte-specific Gsα gene knockout mouse to demonstrate the essential role of Gsα in liver regeneration using a mouse model with 70% partial hepatectomy (PH) or an intraperitoneal injection of carbon tetrachloride (CCl4).