Feeding specialization and activity in certain mangrove crabs

Decapoda is surely one of the most important taxa, both regarding the number of species and individuals, in the macrofauna of the mangrove ecosystem (Macnae, 1968; Macintosh, 1988). For this reason, knowledge about their feeding habits and diet is of primary importance for understanding the energy flow typical of this ecosystem.In Mida Creek and Gazi Bay (Kenya) we collected and then analysed the stomach contents of about 350 crabs belonging to the most common mangrove crab species (excluding the Uca species whose micro-algal feeding habits were already known): Cardisoma carnifex, Epixanthus dentatus, Eurycarcinus natalensis, Metopograpsus oceanicus, M. thukuhar, Sesarma elongatum, S. guttatum, S. leptosoma, S. meinerti, S. ortmanni, Thalamita crenata.Species were divided into classes according to the animal/vegetable matter ratio of their stomach contents.The average stomach fullness proved to be correlated with the degree of vegetable content, being lower in the carnivorous species.Stomach analysis showed that only a few species were strictly herbivorous (mostly feeding on leaf litter) or strictly carnivorous (ambush predators of molluscs or crabs). Instead, magrove crabs seemed to be generally omnivorous, probably due to the low energy and protein content of the food commonly found and to the difficulties in catching suitable prey.For Thalamita crenata, a predator inhabiting the intertidal platform in front of the mangroves, it was also possible to analyse the feeding activity in relation to the different conditions of tide and light. Its feeding activity was higher during the day than at night, and it also seems to feed during low tide, probably catching prey during ebb tides and consuming them when it hides in its shelter

Homing in the mangrove swimming crab <i>Thalamita crenata</i> (Decapoda: Portunidae)

Thalamita crenata is a swimming crab which commonly lives in the shallow waters of sheltered shores of the whole Indo-Pacific region. On the Kenyan coast, this species colonises the intertidal plateau in front of the mangrove. This crab proved to be faithful to a familiar area in which it visited a small number of known holes where it hides during low tide (Vezzosi et al., in prep.). The aim of this study was to test the homing ability of T. crenata after being passively displaced both within the supposed familiar range (internal homing) and outside it (external homing)

Mutant Prevention Concentrations of Imipenem and Meropenem against Pseudomonas aeruginosa

The aim of this study was to determine the usefulness of the MPC of carbapenems against clinical isolates of Pseudomonas spp. and Acinetobacter spp. and to assess its possible relationship with mechanisms of resistance. Detection of the mechanisms of resistance was performed using Antibiotic Susceptibility Testing, Double Disk Synergy, disk antagonism, addition of NaCl to the medium, addition of PBA or EDTA to Carbapenem disks, addition of PBA to Cefoxitin disks, and CCCP test for 10 Pseudomonas spp. and Acinetobacter baumannii strains. The MIC and MPC were determined using the broth macrodilution and plate dilution methods, respectively. Four Acinetobacter baumannii strains produced MBL. Two of them produced Oxacillinase and one produced ESBL. Two Pseudomonas spp. isolates produced both KPC and MBL. The resistant Acinetobacter spp. and Pseudomonas spp. strains had higher MPC values than susceptible ones. However, the Mutant Selection Window was found to be dependent on the degree of resistance but not on a particular mechanism of resistance. The usefulness of the MPC was found to be dependent on its value. Based on our data, we recommend determining the MPC for each isolate before using it during treatment. Furthermore, the use of T>MSW instead of T>MIC is suggested

Impact of Valvular Prosthesis Type on Cardiovascular Outcomes in Patients on Chronic Dialysis

There is conflicting evidence guiding valve prosthesis selection in patients with end-stage renal disease on dialysis. We sought to determine, after reviewing the relevant literature, the best valve substitute in patients on chronic dialysis. A total of 9 retrospective studies compared the outcomes of two valves, showing similar results and highlighting the safety of implanting bioprostheses in patients on chronic dialysis. Standards of valve selection have changed over time; it has long been believed that tissue valves undergo premature degeneration due to calcium metabolism derangements in patients with end-stage renal disease. Bleeding was the most common valve-related complication and represented a major drawback of mechanical valves. Two studies demonstrated a survival advantage in favour of mechanical prostheses. It can be concluded that surgeons should not hesitate to implant bioprostheses because singular valve decomposition would be uncommon in this patient population. Prosthesis selection should be based on the same criteria as those used for non-dialysis patients

Accordion Phenomenon in the Radial Artery : Should we treat the radial as a coronary artery?

The accordion phenomenon is a well-known finding mechanism in the field of interventional cardiology. It is a benign condition and has mainly been described in tortuous coronary arteries during percutaneous coronary interventions. It is believed to be induced by a stiff guidewire. However, this phenomenon has not been observed previously in the radial artery. We present a case of accordion phenomenon in the radial artery, which was successfully resolved after the catheters and the wire were retrieved, with the pseudolesions found to have completely disappeared in subsequent image findings

Characterisation of the crab <i>Neosarmatium meinerti</i> de Man (Decapoda: Sesarminae) predation on <i>Avicennia marina</i> propagules

Mangrove forests are essential for coastal and reef protection. It is an ecosystem providing protection from sedimentation and a range of goods and utilities for local population (Walters et al., 2008). Avicennia marina is a pioneering mangrove species. This tree plays an important role in the colonization and the recolonization of mangroves (Osborn and Beriak., 1997) as it is one of the first species to settle in unforested and deforested areas (loc. cit.). Neosarmatium meinerti is a herbivorous crab, feeding essentially of leaves fallen on the ground and propagules (Dahdouh-Guebas et al., 1997). The propagule predation has a direct impact on mangrove regeneration (Bosire et al., 2005) and therefore on their dynamics. In this perspective we intend to characterize this predation and assess its impact on mangrove forest dynamics and especially on Avicennia marina. We focus on the time and amount of propagules predated upon and on interactions amongst the predators during feeding

Mangrove species' association and distribution patterns in Tumpat, Kelantan Delta, east coast of peninsular Malaysia

We studied mangrove vegetation at Tumpat to estimate different tree structural parameters (e.g., stem density and basal area) at selected sites (PCQ-Method). There were 5 dominant taxa in the vegetation, i.e., Sonneratia caseolaris, Nypa fruticans, Avicennia alba, Rhizophora mucronata, and Bruguiera gymnorrhiza in order of importance. Total tree density varied between 79 and 132 stems 0.1ha-1, and basal area from 0.14 to 4.9m2 0.1ha-1. Based on species composition and stem density, the mangrove sites could be separated into two groups (Bray-Curtis similarity: 60%). While Group-1 (sites G9, J5, K4, N6 and O4), dominated by S. caseolaris and N. fruticans, was distributed throughout the forest, Group-2 (sites C6 and G6), represented largely by A. alba, is present close to the bay-mangrove boundary. Elevation measurements indicate that Group-1 species occupied lowlying to elevated grounds (0.87-2.23m above the mean sea level) with a (mean) salinity between 0.38 and 14.6psu, whereas Group-2 occurred preferentially at low to medium elevations (0.86-1.29m) and high salinity (14.6psu). Discrete mangrove associations (=groupings) were discerned, wherein the distribution of species is governed by factors such as proximity of land or sea, freshwater input and elevation