The Characteristics and Trading Behaviour of Dual-listed Companies

We examine the characteristics and stock price behaviour of existing and recently unified dual-listed companies (DLCs, also known as Siamese-twin companies). DLC structures are effectively mergers in which companies agree to combine their operations and cash flows, but retain separate identities and shareholder registries. We identify 14 such international structures and survey the rationales that have been advanced for the creation as well as the unification of such groups. We find that three recent Anglo-Australian DLCs exhibit the ‘excess comovement’ phenomenon identified by Froot and Dabora (1999) and confirm this phenomenon has persisted for the long-standing Anglo-Dutch DLCs. We also investigate what happens to the market exposures of DLCs that have been abandoned in favour of a unified structure. Standard models would suggest there should be no change in the betas of the combined firm, while models of trading-based comovement would suggest that betas could change. We find that the market value of the unified DLCs becomes more (less) correlated with the market index of the new primary (secondary) market after unification. Together with the evidence for excess comovement, this result is consistent with a model where the market prices of assets depend not only on fundamentals, but also on the location of trade and the investors that hold the assets. Finally, we conduct an event study into the stock returns of DLC twins around the time of unification announcements. Unifications of the share structure have typically occurred on the market that placed the higher value on the cash flows of the DLC. Not surprisingly, the pricing of the twins converges after these announcements, and we find that a rise in the value of the discounted twin is apparently accompanied by a modest fall in the value of the twin trading at a premium.dual-listed company; Siamese twin companies; international equities

Defensins in periodontal health

Defensins are abundant and widely distributed peptides in human and animal tissues that are involved in host defence. Defensins not only have the ability to strengthen the innate immune system but can also enhance the adaptive immune system by chemotaxis of monocytes, T-lymphocytes, dendritic cells and mast cells to the infection site. Defensins also improves the capacity of macrophage phagocytosis. A greater understanding of how these peptides act in the healthy, gingivitis and periodontitis conditions would definitely open new opportunities for identification, prevention and treatment of periodontal diseases. This discussion focuses on recent studies about biological function of defensins in human diseases and animal models

Vitronectin and Fetuin-A: Newfangled Glycoproteins in Periodontits and Coronary Artery Diseases: A Narrative Review

Periodontitis, an intricate inflammatory condition impacting oral support structures, is increasingly recognized as a potential contributor to systemic ailments, notably cardiovascular diseases. Its pathophysiology involves the release of inflammatory molecules like cytokines and chemokines, exacerbating conditions like atherosclerosis. Within this complex web of inflammation, glycoproteins like vitronectin and fetuin-A have emerged as pivotal players, with vitronectin's multifunctional roles in cellular processes and fetuin-A's influence on metabolic pathways. Understanding their involvement in periodontitis and cardiovascular disorders offers promise in leveraging them as diagnostic biomarkers, potentially enhancing disease management and prevention