Atlantic coral reefs: the transplantation alternative

Although all of the world’s coral reef regions have suffered degradation due to direct and indirect human influences, only the Western Atlantic reefs have declined to the extent that their continued existence appears to be in jeopardy. Of a once flourishing reef system, only about 10% is still alive and it is depauperate in terms of the food web diversity necessary to maintain a stable and productive ecosystem. The large carnivores and herbivores have become so scarce that they have failed to control the populations of smaller animals and plants, so that almost all the trophic levels have been disrupted. At the same time, the impacts of many other factors have contributed to the process of degradation resulting in a true crisis. The extent of damage, and the general impairment of regeneration, is such that a hope for natural recovery appears to be unrealistic. It is suggested that a recovery could be achieved through transplantation of corals and other reef species from areas where more diverse, relatively stable ecosystems still exist. Available data on the introduction of exotic species into marine ecosystems indicate that such species are generally accommodated and do not cause extinctions among the native species. Although some introduced species are considered to be pests, others have proved to be beneficial, and all have apparently increased the biodiversity of the invaded areas.     

Mild Myopathy Is Associated with COMP but Not MATN3 Mutations in Mouse Models of Genetic Skeletal Diseases

Pseudoachondroplasia (PSACH) and multiple epiphyseal dysplasia (MED) are skeletal disorders resulting from mutations in COMP, matrilin-3 or collagen IX and are characterised by short-limbed dwarfism and premature osteoarthritis. Interestingly, recent reports suggest patients can also manifest with muscle weakness. Here we present a detailed analysis of two mouse models of the PSACH/MED disease spectrum; ΔD469 T3-COMP (PSACH) and V194D matrilin-3 (MED). In grip test experiments T3-COMP mice were weaker than wild-type littermates, whereas V194D mice behaved as controls, confirming that short-limbed dwarfism alone does not contribute to PSACH/MED-related muscle weakness. Muscles from T3-COMP mice showed an increase in centronuclear fibers at the myotendinous junction. T3-COMP tendons became more lax in cyclic testing and showed thicker collagen fibers when compared with wild-type tissue; matrilin-3 mutant tissues were indistinguishable from controls. This comprehensive study of the myopathy associated with PSACH/MED mutations enables a better understanding of the disease progression, confirms that it is genotype specific and that the limb weakness originates from muscle and tendon pathology rather than short-limbed dwarfism itself. Since some patients are primarily diagnosed with neuromuscular symptoms, this study will facilitate better awareness of the differential diagnoses that might be associated with the PSACH/MED spectrum and subsequent care of PSACH/MED patients.     

Communal living: glycan utilization by the human gut microbiota

Our lower gastrointestinal tract plays host to a vast consortium of microbes, known as the human gut microbiota (HGM). The HGM thrives on a complex and diverse range of glycan structures from both dietary and host sources, the breakdown of which requires the concerted action of cohorts of carbohydrate-active enzymes (CAZymes), carbohydrate-binding proteins, and transporters. The glycan utilization profile of individual taxa, whether ‘specialist’ or ‘generalist’, is dictated by the number and functional diversity of these glycan utilization systems. Furthermore, taxa in the HGM may either compete or cooperate in glycan deconstruction, thereby creating a complex ecological web spanning diverse nutrient niches. As a result, our diet plays a central role in shaping the composition of the HGM. This review presents an overview of our current understanding of glycan utilization by the HGM on three levels: (i) molecular mechanisms of individual glycan deconstruction and uptake by key bacteria, (ii) glycan-mediated microbial interactions, and (iii) community-scale effects of dietary changes. Despite significant recent advancements, there remains much to be discovered regarding complex glycan metabolism in the HGM and its potential to affect positive health outcomes.     

POST-TUBERCULOUS BRONCHIECTASIS—Indications for Surgical Treatment

Two hundred twelve of 308 post-tuberculous patients were found to have significant bronchiectasis; and in 105 of them, in whom certain symptoms or combinations of symptoms and conditions were observed, resectional operations were carried out. Good results were obtained in 81 per cent of the group. There were serious complications in 13 per cent. Three of the patients died, two after pneumonectomy, one after lobectomy plus segmental excision.