Phenotypic convergence is more frequent and stronger in herbivorous freshwater fishes.

Constraints on phenotypic evolution can lead to patterns of convergent evolution, by limiting the 'pool' of potential phenotypes in the face of endogenous (functional, developmental) or exogenous (competition, predation) selective pressures. Evaluation of convergence depends on integrating ecological and morphological data within a robust, comparative phylogenetic context. The staggering diversity of teleost fishes offers a multitude of lineages adapted for similar ecological roles, and therefore, offers numerous replicated evolutionary experiments for exploring phenotypic convergence. However, our understanding of fish feeding systems has been primarily shaped by marine species, with the monolithic exception of freshwater cichlids. Here we use piranhas and pacus (Serrasalmidae) to explore the evolution of different feeding ecologies and their morphological proxies in Neotropical freshwater environments. Specifically, we explore whether convergence is more widespread among plant-eating fishes, arising from strong constraints on phenotypic evolution in herbivores. Using osteological micro-computed tomographic imaging (µCT), we describe the major axes of morphological variation in pacus and piranhas, regarding their diet and feeding behaviors. Next, we evaluated whether herbivorous niches are less labile than other dietary guilds and whether herbivorous species' phenotypes evolve at a slower evolutionary rate than other taxa. We then assess how convergent herbivorous taxa are, using three different suites of morphological characters (dental, jaw, and abdominal morphometrics). Ecologically, herbivory is not a dead end, exhibiting similar observed transition rates as those between carnivores and omnivores. However, we documented widespread convergence in herbivores and that herbivores have slower rates of phenotypic evolution than carnivores. Most instances of convergence are found in herbivorous taxa, specifically in frugivores and folivores. Moreover, instances of 'complete' convergence, indicated by positive convergence metrics observed in more than one morphometric dataset, were only found in herbivores. Herbivores do appear to evolve under constrained circumstances, but this has not limited their ecological lability.

Reproductive morphology and its application in testing molecular systematic hypotheses in the family Gobiidae (Teleostei, Gobiiformes).

This study uses histological techniques to make a detailed comparison of the reproductive morphologies of four gobiid genera, Amblyeleotris, Ctenogobiops, Fusigobius and Kraemeria. Three distinct reproductive morphological patterns were observed. All species examined in the genus Fusigobius exhibit either an ovariform or testiform gonad and precursive accessory gonadal structures (pAGS) associated with each of the gonadal lobes, regardless of gonadal state. In contrast, among species of Amblyeleotris, Ctenogobiops and Kraemeria examined, pAGS were not found. Furthermore, Amblyeleotris and Ctenogobiops differ from both Kraemeria and Fusigobius in lacking AGS associated with the testiform gonad. These findings, based solely on reproductive morphology, suggest that Kraemeria and Fusigobius may be more closely related to each other than either is to Amblyeleotris and Ctenogobiops. Findings of this study support the view that reproductive morphological patterns could prove informative in elucidating evolutionary relationships within the family Gobiidae.

Mid-term follow-up of stenting in chronic mesenteric ischaemia: a review of six cases.

BACKGROUND: Chronic mesenteric angina is a rare condition with high morbidity and mortality, which occurs due to stenosis or occlusion in the mesenteric vessels commonly due to atherosclerosis. Typically, patients present with worsening postprandial abdominal pain, chronic weight loss and fear of food. The condition can be treated by surgical bypass, but also by percutaneous transluminal angioplasty and stenting of the affected mesenteric arteries. AIM: To assess the mid-term outcomes in patients treated by endovascular stenting for chronic mesenteric ischaemia (CMI). METHODS: Six patients were treated for symptomatic CMI. In total, six severely stenosed vessels were stented including the superior mesenteric artery (n = 5) and coeliac artery (n = 1). A retrospective review of these patients was performed with end points including symptom recurrence, major morbidity and mortality. The mean follow-up was 16.5 months (range 5-28 months). RESULTS: Initial clinical success was observed in all six patients. Four patients were clinically asymptomatic, but died within 18 months after the procedure from other conditions. One patient suffered from recurrence of symptoms. Only one patient died as a consequence of mesenteric artery re-stenosis. CONCLUSION: Stenting of mesenteric vessels has shown excellent early and mid-term clinical success in selected patients. Though no direct comparison with open revascularization surgery was performed in this case series, technical and mid-term clinical success is promising.

Arbaprostil's [15(R)-15-methyl PGE2] effects on intrauterine pressure in the nonpregnant and pregnant human female--a report of four clinical trials.

Four clinical trials evaluating arbaprostil's effects on the human uterus are reported. The initial two trials measured intrauterine pressures in nonpregnant and pregnant human females following arbaprostil doses of 10, 25, and/or 50 mcg. No statistical differences were found at any dosage level in either study for average uterine resting pressures, average peak pressures, the number of contractions or Montevideo units. Subsequently, two trials determined the abortifacient potential of arbaprostil in pregnant women during the first trimester. The first utilized total daily doses of 400 and 800 mcgs. while the second used total daily doses of 1200 and 1600 mcgs. Vaginal spotting was noted in one woman receiving 400 mcgs, three receiving 1200 mcgs. and in two receiving 1600 mcgs. One episode of moderate bleeding was seen in the latter study. Based on these studies, arbaprostil exhibits little potential for inducing abortifacient activity at these dosages in these patient populations.

Leucocyte locomotion: comparison of random and directed paths using a modified time-lapse film analysis.

A semi-automated method, using a graphic digitizing tablet, for analysing the the tracks of cells taken from time-lapse film is described and illustrated with sample data. Three film sequences of neutrophil leucocytes moving on protein-coated substrata are analysed, and in one of these the cells are moving in a non-random fashion. The randomness of the tracks is tested by an objective method. Cells in the non-random (directed) sequence move faster and make smaller angled turns. No correlation between step length and turning angle could be shown for the random sequences. The method described here should make it possible to undertake visual analyses of cell locomotion with considerably less effort.

Semiautomatic processing of neurophysiological data: part I--a device for measuring potential intervals from film.

This paper describes the operation and construction of an electromechanical device designed to make measurements on oscillograph recordings of nerve or muscle potentials for subsequent computer analysis. The device consists of a motor-driven shaft which moves the record past a fixed cursor, and an electronic counter which records the movements of the shaft, thereby providing a cumulative tally of the distance of the current position of the cursor from some arbitrary origin on the record. When the device is connected to a paper tape punch, the operator can punch the distance measurement associated with potential along the record onto the tape. The format of data on the tape readily allows further analysis by computer.