The role of peptides in bone healing and regeneration: A systematic review

Background: Bone tissue engineering and the research surrounding peptides has expanded significantly over the last few decades. Several peptides have been shown to support and stimulate the bone healing response and have been proposed as therapeutic vehicles for clinical use. The aim of this comprehensive review is to present the clinical and experimental studies analysing the potential role of peptides for bone healing and bone regeneration. Methods: A systematic review according to PRISMA guidelines was conducted. Articles presenting peptides capable of exerting an upregulatory effect on osteoprogenitor cells and bone healing were included in the study. Results: Based on the available literature, a significant amount of experimental in vitro and in vivo evidence exists. Several peptides were found to upregulate the bone healing response in experimental models and could act as potential candidates for future clinical applications. However, from the available peptides that reached the level of clinical trials, the presented results are limited. Conclusion: Further research is desirable to shed more light into the processes governing the osteoprogenitor cellular responses. With further advances in the field of biomimetic materials and scaffolds, new treatment modalities for bone repair will emerge

An Estimate of Avian Mortality at Communication Towers in the United States and Canada

Avian mortality at communication towers in the continental United States and Canada is an issue of pressing conservation concern. Previous estimates of this mortality have been based on limited data and have not included Canada. We compiled a database of communication towers in the continental United States and Canada and estimated avian mortality by tower with a regression relating avian mortality to tower height. This equation was derived from 38 tower studies for which mortality data were available and corrected for sampling effort, search efficiency, and scavenging where appropriate. Although most studies document mortality at guyed towers with steady-burning lights, we accounted for lower mortality at towers without guy wires or steady-burning lights by adjusting estimates based on published studies. The resulting estimate of mortality at towers is 6.8 million birds per year in the United States and Canada. Bootstrapped subsampling indicated that the regression was robust to the choice of studies included and a comparison of multiple regression models showed that incorporating sampling, scavenging, and search efficiency adjustments improved model fit. Estimating total avian mortality is only a first step in developing an assessment of the biological significance of mortality at communication towers for individual species or groups of species. Nevertheless, our estimate can be used to evaluate this source of mortality, develop subsequent per-species mortality estimates, and motivate policy action

Clinical management of liver cyst infections:an international, modified Delphi-based clinical decision framework

Liver cyst infections often necessitate long-term hospital admission and are associated with considerable morbidity and mortality. We conducted a modified Delphi study to reach expert consensus for a clinical decision framework. The expert panel consisted of 24 medical specialists, including 12 hepatologists, from nine countries across Europe, North America, and Asia. The Delphi had three rounds. The first round (response rate 21/24 [88%]) was an online survey with questions constructed from literature review and expert opinion, in which experts were asked about their management preferences and rated possible management strategies for seven clinical scenarios. Experts also rated 14 clinical decision-making items for relevancy and defined treatment outcomes. During the second round (response rate 13/24 [54%]), items that did not reach consensus and newly suggested themes were discussed in an online panel meeting. In the third round (response rate 16/24 [67%]), experts voted on definitions and management strategies using an online survey based on previous answers. Consensus was predefined as a vote threshold of at least 75%. We identified five subclassifications of liver cyst infection according to cyst phenotypes and patient immune status and consensus on episode definitions (new, persistent, and recurrent) and criteria for treatment success or failure was reached. The experts agreed that fever and elevated C-reactive protein are pivotal decision-making items for initiating and evaluating the management of liver cyst infections. Consensus was reached on 26 management statements for patients with liver cyst infections across multiple clinical scenarios, including two treatment algorithms, which were merged into one after comments. We provide a clinical decision framework for physicians managing patients with liver cyst infections. This framework will facilitate uniformity in the management of liver cyst infections and can constitute the basis for the development of future guidelines.</p

The role of P2O5, TiO2 and ZrO2 as nucleating agents on microstructure and crystallization behaviour of lithium disilicate-based glass

The aim of this study was to investigate the effects of different nucleating agents (P2O5, TiO2 and ZrO2) on the crystallization behaviour and the properties of a parent glass with composition 23.7 Li2O-2.63 K2O-2.63 Al2O3-71.78 SiO2 (mol%) and SiO2/Li2O molar ratio far beyond that of stoichiometric lithium disilicate (LD, Li2Si2O5). The scanning electron microscopy examination of the as-cast non-annealed glasses revealed the occurrence of liquid-liquid phase separation for all the compositions. P2O5 revealed to be effective in promoting bulk crystallization of LD, while TiO2 and ZrO2 led to surface crystallization. Moreover, ZrO2 enhances the glass polymerization and shifts T-p to higher temperatures, hindering crystallization. At 900 degrees C, TiO2-containing glasses feature LD and lithium metasilicate (LMS, Li2SiO3), while P2O5- and ZrO2-containing ones present monophasic LD and LMS glass-ceramics, respectively