A survey by hydraulic dredge of interstitial bivalves with commercial potential in Cill Chiaráin and Beirtreach buí Bays and along their connecting shoreline, Co Galway

The shellfish co-operative, Comharchuman Sliogéisc Chonamara Teó (CSC) manages oyster and scallop in Beirtreach buí and Cill Chiaráin Bays, both of which are designated aquaculture areas. Cill Chiaráin is also a candidate Special Area of Conservation (cSAC). Various traditional fishing activities are carried on in the bays and CSC has rights to exploit clam species there. The work described here is a survey of interstitial clam species by hydraulic dredge between November 2001 and January 2002. Investigations were restricted from some of the upper bay areas where surface bivalve management was in progress. Much of the remaining areas within the Bays proved unsuitable for hydraulic dredging by virtue of the nature of the substratum. The exposed parts of the lower bays and the intervening coastline where the substratum was coarse sand (maërl or shell sand) were suitable for hydraulic dredging but bedrock and loose boulders often proved obstacles to towing. There was evidence of two assemblages of bivalves in the bays: one typified by Venus verrucosa, Venerupis senegalensis and Tapes rhomboides, all large and potentially valuable, occurred within maërl mixed with fine mud, the other whose most valuable components included Ensis arcuatus and Spisula solida, occurred in disintegrating maërl and in shell sand. The bivalve fauna in the two bays appeared to be typified by relatively high diversity and low biomass – which is accentuated by recent natural mortalities of Ensis arcuatus, a dominant species - and this is likely to prove a challenge to marketing; the Irish market typically exploits small numbers of clam species simultaneously. The terms of the licence under which CSC operates may provide opportunities to exploit clams within their designated area by means other than hydraulic dredging and these should be investigated. In view of the scientific values of the area and its status as a cSAC any plan to exploit its interstitial bivalves should be discussed with the relevant state agency.Funder: Marine Institut

The Role of Purported Mucoprotectants in Dealing with Irritable Bowel Syndrome, Functional Diarrhea, and Other Chronic Diarrheal Disorders in Adults

Chronic diarrhea is a frequent presenting symptom, both in primary care medicine and in specialized gastroenterology units. It is estimated that more than 5% of the global population suffers from chronic diarrhea. and that about 40% of these subjects are older than 60 years. The clinician is frequently faced with the need to decide which is the best therapeutic approach for these patients. While the origin of chronic diarrhea is diverse, impairment of intestinal barrier function, dysbiosis. and mucosal micro-inflammation are being increasingly recognized as underlying phenomena characterizing a variety of chronic diarrheal diseases. In addition to current pharmacological therapies, there is growing interest in alternative products such as mucoprotectants, which form a mucoadhesive film over the epithelium to reduce and protect against the development of altered intestinal permeability, dysbiosis, and mucosal micro-inflammation. This manuscript focuses on chronic diarrhea in adults, and we will review recent evidence on the ability of these natural compounds to improve symptoms associated with chronic diarrhea and to exert protective effects for the intestinal barrier

Newer insights into the mechanism of action of <it>Psidium guajava </it>L. leaves in infectious diarrhoea

<p>Abstract</p> <p>Background</p> <p><it>Psidium guajava </it>L., Myrtaceae, is used widely in traditional medicine for the treatment of diarrhoea, dysentery, gastroenteritis, stomachaches, and indigestion. However, the effect of the leaf extract of <it>P. guajava </it>on the pathogenesis of infectious diarrhoea has not been studied. The present study evaluates the effect of a hot aqueous extract (decoction) of dried leaves of <it>P. guajava </it>on parameters associated with pathogenicity of infectious diarrhoea. The aim was to understand its possible mechanism(s) of action in controlling infectious diarrhoea and compare it with quercetin, one of the most reported active constituents of <it>P. guajava </it>with antidiarrhoeal activity.</p> <p>Methods</p> <p>The crude decoction and quercetin were studied for their antibacterial activity and effect on virulence features of common diarrhoeal pathogens viz. colonization of epithelial cells and production and action of enterotoxins. Colonization as measured by adherence of enteropathogenic <it>Escherichia coli </it>(EPEC) and invasion of enteroinvasive <it>E. coli </it>(EIEC) and <it>Shigella flexneri </it>was assessed using HEp-2 cell line. The production of <it>E. coli </it>heat labile toxin (LT) and cholera toxin (CT) and their binding to ganglioside monosialic acid (GM1) were studied by GM1-ELISA whereas the production and action of <it>E. coli </it>heat stable toxin (ST) was assessed by suckling mouse assay.</p> <p>Results</p> <p>The decoction of <it>P. guajava </it>showed antibacterial activity towards <it>S. flexneri </it>and <it>Vibrio cholerae</it>. It decreased production of both LT and CT and their binding to GM1. However, it had no effect on production and action of ST. The decoction also inhibited the adherence of EPEC and invasion by both EIEC and <it>S. flexneri </it>to HEp-2 cells. Quercetin, on the other hand, had no antibacterial activity at the concentrations used nor did it affect any of the enterotoxins. Although it did not affect adherence of EPEC, it inhibited the invasion of both EIEC and <it>S. flexneri </it>to HEp-2 cells.</p> <p>Conclusion</p> <p>Collectively, the results indicate that the decoction of <it>P. guajava </it>leaves is an effective antidiarrhoeal agent and that the entire spectrum of its antidiarrhoeal activity is not due to quercetin alone.</p