Surgical versus medical management of patients with primary hyperaldosteronism and indeterminate adrenal vein sampling: A 10-year experience of the Cleveland Clinic

In patients with primary hyperaldosteronism (PA), adrenal vein sampling (AVS) can identify patients suitable for unilateral adrenalectomy. However, in AVS with an indeterminate aldosterone-to-cortisol lateralization (ACL) ratio of 3.0-4.0, clinical guidance is unclear. The authors screened all patients undergoing AVS at the Cleveland Clinic from October 2010 to January 2021 and identified 18 patients with indeterminate ACL results. Ten underwent adrenalectomy and eight continued medical management. The surgical group was younger (58.5 vs. 68 years, p = .17), and more likely to have a unilateral imaging adrenal abnormality (90% vs. 38%, p = .043) and a lower contralateral suppression index (0.63 vs. 1.1, p = .14). Post-treatment, the surgical group had a significant reduction in diastolic blood pressure (-5.5 mmHg, p = .043) and aldosterone (4.40 vs. 35.80 ng/mL, p = .035) and required fewer anti-hypertensive medications (2 vs. 3, p = .015). These findings may support the benefit of adrenalectomy in a select group of patients with indeterminate ACL.

Mechanistic insights into bone remodelling dysregulation by human viral pathogens

Bone-related diseases (osteopathologies) associated with human virus infections have increased around the globe. Recent findings have highlighted the intricate interplay between viral infection, the host immune system and the bone remodelling process. Viral infections can disrupt bone homeostasis, contributing to conditions such as arthritis and soft tissue calcifications. Osteopathologies can occur after arbovirus infections such as chikungunya virus, dengue virus and Zika virus, as well as respiratory viruses, such as severe acute respiratory syndrome coronavirus 2 and enteroviruses such as Coxsackievirus B. Here we explore how human viruses dysregulate bone homeostasis, detailing viral factors, molecular mechanisms, host immune response changes and bone remodelling that ultimately result in osteopathologies. We highlight model systems and technologies to advance mechanistic understanding of viral-mediated bone alterations. Finally, we propose potential prophylactic and therapeutic strategies, introduce 'osteovirology' as a research field highlighting the underestimated roles of viruses in bone-related diseases, and discuss research avenues for further investigation.

Lon Protease Has Multifaceted Biological Functions in Acinetobacter baumannii

Acinetobacter baumannii is a Gram-negative opportunistic pathogen that is known to survive harsh environmental conditions and is a leading cause of hospital-acquired infections. Specifically, multicellular communities (known as biofilms) of A. baumannii can withstand desiccation and survive on hospital surfaces and equipment. Biofilms are bacteria embedded in a self-produced extracellular matrix composed of proteins, sugars, and/or DNA. Bacteria in a biofilm are protected from environmental stresses, including antibiotics, which provides the bacteria with selective advantage for survival. Although some gene products are known to play roles in this developmental process in A. baumannii, mechanisms and signaling remain mostly unknown. Here, we find that Lon protease in A. baumannii affects biofilm development and has other important physiological roles, including motility and the cell envelope. Lon proteases are found in all domains of life, participating in regulatory processes and maintaining cellular homeostasis. These data reveal the importance of Lon protease in influencing key A. baumannii processes to survive stress and to maintain viability.IMPORTANCEAcinetobacter baumannii is an opportunistic pathogen and is a leading cause of hospital-acquired infections. A. baumannii is difficult to eradicate and to manage, because this bacterium is known to robustly survive desiccation and to quickly gain antibiotic resistance. We sought to investigate biofilm formation in A. baumannii, since much remains unknown about biofilm formation in this bacterium. Biofilms, which are multicellular communities of bacteria, are surface attached and difficult to eliminate from hospital equipment and implanted devices. Our research identifies multifaceted physiological roles for the conserved bacterial protease Lon in A. baumannii These roles include biofilm formation, motility, and viability. This work broadly affects and expands understanding of the biology of A. baumannii, which will permit us to find effective ways to eliminate the bacterium.