First report of Kudoa sp. in the palate and pharyngeal musculature of Gobioides grahamae Palmer and Wheeler, 1955 (Perciformes, Gobiidae) from Marajó Island, Brazil

ABSTRACT The aim of this study was to describe the first occurrence ofKudoasp. inGobioides grahamae, contributing to the understanding of this group of parasites in the Amazonian ichthyofauna. Forty specimens ofG. grahamaecollected from the natural environment were analyzed. Cysts ofKudoasp. were diffusely distributed through the striated skeletal muscle fibers with severe edema and inflammatory infiltrate composed of lymphocytes were observed in 30% of the specimens. Edema and marked coagulation necrosis of the muscle fibers was associated with infection byKudoasp. spores, which had accumulated inside the skeletal muscle fibers. Although there are no records of foodborne outbreaks caused by Kudoa spp. in Brazil, it is of paramount importance that we evaluate its occurrence, since the consumption of fish, especially raw fish, has increased because of the adoption of Japanese cuisine. To minimize the economic impacts on the fisheries market and the risk of this parasite to public health, it is necessary to initiate a program to monitor the presence of this likely underdiagnosed, emerging parasite.

The Role of Developmental Integration and Historical Contingency in the Origin and Evolution of Cypriniform Trophic Novelties

While functional morphologists have long studied the evolution of anatomical structures, the origin of morphological novelties has received less attention. When such novelties first originate they must become incorporated into an integrated system to be rendered fully functional. Thus, developmental integration is key at the origin of morphological novelties. However, given enough evolutionary time such integration may be broken, allowing for a division of labor that is facilitated by subsequent decoupling of structures. Cypriniformes represent a diverse group of freshwater fishes characterized by several trophic novelties that include: kinethmoid-mediated premaxillary protrusion, a muscular palatal and post-lingual organ, hypertrophied lower pharyngeal jaws that masticate against the base of the neurocranium, novel pharyngeal musculature controlling movement of the hypertrophied lower pharyngeal jaws, and in a few species an incredibly complex epibranchial organ used to aggregate filtered phytoplankton. Here, we use the wealth of such trophic novelties in different cypriniform fishes to present case studies in which developmental integration allowed for the origin of morphological innovations. As proposed in case studies 1 and 2 trophic innovations may be associated with both morphological and lineage diversification. Alternatively, case studies 3 and 4 represent a situation where ecological niche was expanded but with no concomitant increase in species diversity.

Use of botulinum toxin in voice restoration after laryngectomy

Background:Following laryngectomy, a distinct population of patients fails to achieve successful tracheoesophageal voice. These patients' voices range from strained and effortful to none at all. Such patients may present with severe hypertonicity or spasm of the pharyngoesophageal segment. Botulinum toxin has been used to chemically denervate the pharyngeal musculature, and is an alternative to invasive surgical procedures. The aim of this article is to review the evidence for using botulinum toxin to achieve an improvement in post-laryngectomy voice.Methods:A Medline literature review (1966 to January 2009) and a search of the Cochrane database were performed. Foreign language articles and those not pertaining to post-laryngectomy voice restoration were excluded.Results:Nine articles reporting a total of 134 patients were identified. Although there were differences in the outcome measures used, objective improvement in voice production occurred in between 70 and 100 per cent of cases.Conclusion:Botulinum toxin can be used as a safe and cost-effective treatment in patients with confirmed pharyngoesophageal segment hypertonicity and/or spasm following laryngectomy, to obtain an improvement in voice quality.

Electropharyngeograms of pharyngeal pumping activity in six species of free-living nematodes

Analysis of the contraction and relaxation of pharyngeal musculature derives from measurements of electrical currents, termed electropharyngeograms (EPG). EPG were recorded from adults of six species of free-living nematodes, Anatonchus amiciae, Aporcelaimus superbus, Plectus parietinus, Mesorhabditis cranganorensis, Seleborca complexa and Panagrellus redivivus, during exposure to artificial pond water (APW) and to 0.1 mg ml-1 of the neurotransmitter serotonin for 5, 10 and 15 min. A marked difference was observed in the pharyngeal muscle activity of species with grinders in a three-part pharynx compared with that in species with cylindroid or two-part pharynx without grinders. The EPG results from the non-grinder predator A. amiciae showed no electrical activity in response to either APW or serotonin. There was no electrical activity from the non-grinder predator Aporcelaimus superbus in APW and only occasional electrical activity when it was exposed to serotonin; no stylet activity was observed in this species in any treatment combination. The four grinder species, P. parietinus, M. cranganorensis, S. complexa and P.redivivus, gave consistent EPG results in APW, irrespective of the period of exposure. The time intervals between two consecutive pharyngeal pumps were between 1.0 and 1.5 s for M. cranganorensis, S. complexa and P. redivivus but pharyngeal activity of P. parietinus was much slower with intervals of 4.8-4.9 s between two pumps. The effect of serotonin on these four species was inconsistent. Only P.redivivus showed EPG responses that demonstrated an enhanced rate of pharyngeal pumping; the rate of pumping of this species also increased with increase in exposure period to serotonin.

Electropharyngeograms and stylet activity of second stage juveniles of Globodera rostochiensis

Analysis of the contraction and relaxation of pharyngeal musculature derives from measurements of electrical currents, termed electropharyngeograms (EPG). EPG of stylet protractor muscle activity of second stage juveniles (J2) of Globodera rostochiensis, in response to 0.1, 1.0 and 10 mg ml-1 concentrations of the neurotransmitter serotonin, have now been obtained and correlated with stylet protrusion and retraction using video analysis. The antagonist, gramine (10 mg ml-1), incorporated with 10 mg ml-1 serotonin, almost completely eliminated stylet thrusting by J2. Stylet movement can be determined accurately over extended periods with EPG and this approach has potential for investigating factors involved in activation and perturbation of stylet protrusion.

Structure and evolution of the pharynx in the Temnocephalida (Platyhelminthes)

The structure of the pharynx was studied in the genera Didymorchis, Diceratocephala, Temnocephala, and Craspedella, using light microscopy, silver nitrate staining, and transmission electron microscopy. Based on these data, evolution of this organ within the Temnocephalida is analysed. In addition to the specific pattern of muscle fibres in the walls of the pharynx known from earlier studies, three other features characteristic of the pharynges of temnocephalids were found: (1) multisyncytial organization of the pharyngeal epithelium, (2) the presence of type 1 sensory receptors, and (3) muscle fibres incorporated into the epithelium of the pharynx. Features deduced to be characteristic of the pharynx in primitive temnocephalids are (i) the presence of three types of sensory receptors with specific morphologies and locations in the pharynx, (ii) the presence of a bundle of muscle fibres that traverses the epithelium surrounding the anterior margin of the pharynx, (iii) characteristic lamellation of the epithelium of the pharynx proper, and (iv) a narrow syncytium nesting the openings of the pharyngeal glands and forming deep invaginations into which the gland ducts open. The most prominent tendencies in the evolution of the pharynx are reinforcement of the pharyngeal musculature (related to the mode of feeding) and reduction in the number of syncytia.