bluuebunny/crossref_metadata_2025 huggingface dataset:
Variation in age at first reproduction of male Japanese fluvial sculpin induced by the timing of parental reproduction
Authors: Natsumeda T.
Published: August 2010

The relationships between age and size at reproduction and lifetime reproductive output of male Japanese fluvial sculpin Cottus pollux were estimated by a mark‐recapture study. Although all males were physiologically capable of breeding at age 2 years, age at first successful reproduction varied amongst individuals. Males with delayed reproduction had lower net reproductive rate than males that bred at age 2 years on average suggesting that age at first reproduction was a conditional strategy. Males that delayed reproduction were significantly smaller at age 1 and 2 years than males that bred at age 2 years. Despite no significant difference in body size of hatched yolk‐sac larvae between the early and late phase of the breeding season, by May of the first year of life, progeny from nests in the early phase had hatched earlier and were larger than those from the nests in the late phase. The results suggested an important effect of timing of reproduction of parents on the growth and subsequent age at first reproduction of their progeny.
Comparative oocyte morphology and early development in three species of trahiras from the São Francisco River basin, Brazil
Authors: Gomes B. V. C. , Scarpelli R. S. , Arantes F. P. , Sato Y. , Bazzoli N. , Rizzo E.
Published: August 2010

Oocyte morphology, embryogenesis and early larval development were compared in Hoplerythrinus unitaeniatus, Hoplias lacerdae and Hoplias malabaricus (Characiformes: Erythrinidae) by macroscopical, histological, histochemical and ultrastructural analyses. The eggs of the three species were yellowish and adhesive, containing carboxyl and sulphate radicals in the glycoconjugates of the zona radiata. A complex surface arrangement was identified in oocytes of H. unitaeniatus and H. lacerdae, while H. malabaricus had a simple oocyte surface pattern. Lectin histochemistry revealed different carbohydrate terminal residues in cortical alveoli, outer zona radiata and follicular cells of the three species. At the animal pole, the oocyte surface topography surrounding the micropyle was species‐specific. The micropylar cell was ConA‐positive, suggesting the presence of carbohydrates with mannose/glucose terminal residues that could have a role during fertilization. The erythrinids exhibited a prolonged embryonic and larval development compared to other Characiformes, a reproductive strategy used for increasing offspring protection. Early development proceeded most rapidly in H. unitaeniatus, followed by H. malabaricus and then H. lacerdae, which could have more developed parental care behaviour. An adhesive organ composed of secretory prismatic cells protruding from the cephalic region of the three erythrinid larva allowed them to attach to one another during development. Reproductive behaviour and early developmental strategies were similar in the three species, but the oocyte surface morphology suggests a close relationship between H. unitaeniatus and H. lacerdae.
Metazoan parasites of Engraulis ringens as tools for stock discrimination along the Chilean coast
Authors: Valdivia I. M. , Chávez R. A. , Oliva M. E.
Published: August 2010

The value of the metazoan parasites of the anchoveta Engraulis ringens as biological tags for stock discrimination is assessed. Three hundred and fifty‐nine specimens, obtained from six landing ports in northern and central Chile (Arica, Antofagasta, Caldera, Coquimbo, Valparaiso and Talcahuano) covering a latitudinal gradient of c. 18°, were analysed. Six metazoan parasite species (three ectoparasites and three endoparasites) were obtained. A correspondence analysis suggested that anchoveta from northern and central Chile are comprised of two stocks. Identification of stocks was largely based on qualitative differences (absence in southern localities of the monogenean Pseudanthocotyloides heterocotyle, a parasite proper of engraulids, and the copepod Caligus sp.) and quantitative differences in the prevalence of infection for the remaining species. Inertia and mass value for the correspondence analysis supported the hypothesis of two stocks.
Shoaling in eyed and blind morphs of the characin Astyanax fasciatus under light and dark conditions
Authors: Gregson J. N. S. , Burt de Perera T.
Published: August 2010

The shoaling behaviour of the visual, epigean morph of the characin Astyanax fasciatus was found to be quantitatively different from the blind, hypogean morph.
Biochemical and histochemical study on the intestinal mucosa of the common carp Cyprinus carpio L., with special consideration of mucin glycoproteins
Authors: Neuhaus H. , Van der Marel M. , Caspari N. , Meyer W. , Enss M.‐L. , Steinhagen D.
Published: August 2010

The biochemical and histochemical properties of intestinal mucin glycoproteins of virus and parasite‐free common carp Cyprinus carpio were investigated. The presence of carbohydrates in mucin glycoproteins could be demonstrated by histochemical methods, but generally, no obvious differences in specific staining for mucin glycoproteins were observed in contrast to biochemical techniques. Biochemical staining methods displayed differences in structure and composition of intestinal glycoproteins. Released intestinal glycoproteins contained two types of mucin glycoproteins: type 1 mucins displayed a size of >2000 kDa, and were highly glycosylated, while type 2 mucins ranged between 700 and 70 kDa, and were weakly glycosylated. In epithelial (intracellular) glycoproteins, mainly N‐acetyl‐α‐galactosamine and mannose were found, while in luminal (extracellular) glycoproteins in addition sialic acid was evident. Fucose was not detected. Thus, structure and composition of intestinal glycoproteins of common carp were similar to those found in mammals.
Distribution patterns and sexual segregations ofScyliorhinus canicula(L.) in the Cantabrian Sea
Authors: Rodríguez‐Cabello C. , Sánchez F. , Olaso I.
Published: August 2010

The influence of factors such as depth, near bottom temperature, near bottom salinity, fish length and diet composition on the aggregation ofScyliorhinus caniculain the Cantabrian Sea was examined. The correlation between these variables and the aggregations of each sex was low.A priorijuvenile males and females were not highly discriminated by any of these environmental variables (depth, temperature and salinity) based on a multivariate analysis. The best discriminated groups were the new recruits, and depth and longitude were the variables that contributed most to their segregation, while adult males had some preference for shallower and warm waters. Diet composition varied with body size but it was quite similar in both sexes among which no significant differences were observed. An increase in feeding intensity and abundance of Euphasiacea prey taxa was found in adult females compared to males.
Effect of habitat shifts on feeding behaviour and growth of 0 year‐group flounderPlatichthys flesus(L.) transferred between macroalgae and bare sand habitats
Authors: Grønkjær P. , Carl J. D. , Rasmussen T. H. , Hansen K. W.
Published: August 2010

In this study, short‐term growth and feeding behaviour were compared among juvenile European flounderPlatichthys flesusreared in enclosures in either their native habitat (bare sand or vegetation) or transferred to the opposite habitat. Growth was poorest in the vegetated habitat regardless of origin of the fish. The effect of the habitat shift differed between years. In 2000, the relatively small fish used grew fastest in their native habitat. In contrast, in 2001 when larger fish were used, growth was similar between native and introduced fish in the vegetated habitat, and introduced fish grew faster than native fish in the bare sand habitat. Diet composition and feeding intensity within a habitat were also similar among native and introduced fish in 2001, suggesting that the habitat switch had a minor influence on foraging efficiency. The different results obtained from the experiments in 2000 and 2001 suggest that fish size may determine the extent to which short‐term habitat shifts influence feeding and growth in juvenile flounder, and, importantly, that the negative effects of habitat fragmentation are more severe for small compared to larger juvenile flounder.
Familiarity‐biased patterns of association shift with time among European minnows
Authors: Griffiths S. W. , Ojanguren A. F. , Orpwood J. E. , Magurran A. E. , Armstrong J. D.
Published: August 2010

Replicated, naturalistic mesocosms were used to investigate whether pre‐existing preferences for familiar individuals decay when opportunities to form new alliances arise. In each trial, two groups of wild European minnowsPhoxinus phoxinuswere introduced to a common environment, and their association patterns monitored continuously over a 3 week period using passive integrated transponder (PIT) tags. Individuals within a group were familiar, but had no previous experience of the other group. European minnows associated initially with previously familiar individuals more frequently than expected by chance. This preference then diminished over a period of 2 weeks following their encounter with the unfamiliar group of fish and was not detectable by the third week. Instead, new association patterns resulting from non‐random re‐assortment of individuals over time were evident. The results show that new alliances between individuals form when wild shoals coalesce.
Synchrony in the downstream migration of smolts and upstream migration of adult Atlantic salmon in the subarctic River Utsjoki
Authors: Orell P. , Erkinaro J. , Svenning M. A. , Davidsen J. G. , Niemelä E.
Published: August 2010

Seasonal and diel migration timing of wild Atlantic salmonSalmo salarsmolts and adults were investigated annually (2001–2004) in the subarctic River Utsjoki, a tributary of the large River Teno (70° N), using underwater video monitoring. Submerged video cameras provided information on the exact timing and intensity of both migrations in a natural river channel, without disturbing the fish. In contrast to the mainly nocturnal migration pattern described from temperate rivers, the River Utsjoki smolts and adults migrated throughout the day. Smolts migrated most intensively during hours of rising (0300–0900 hours) and high sun (0900–1500 hours), while adults favoured the period of low sun (2100–0300 hours). Smolt migrations started in June and lasted on average 42 days. Adults usually ascended the site 2–3 weeks before the first descending smolts were observed and the adult migrations extended to the end of August. Seasonal synchrony was observed between smolt and adult migrations in years of slowly warming water, whereas in a year of exceptionally warm early summer (2002), smolts migrated earlier than adults. Thus, water temperature seemed to be an important environmental factor triggering the smolt migration, while the migration of adults was probably more fixed to a certain season. Weak positive correlations between fish counts and water temperature were observed, indicating that increasing water temperature may have promoted both smolt and adult migrations. The influence of discharge was negligible, although increasing discharge late in the season may have activated the remaining individuals in both groups.
The effects of copper, iron and zinc on digestive enzyme activity in the hybrid tilapia Oreochromis niloticus (L.) ×Oreochromis aureus (Steindachner)
Authors: Li J.‐S. , Li J.‐L. , Wu T.‐T.
Published: August 2010

The present experiment was conducted to study effects of Cu, Fe and Zn on activities of digestive enzymes of the hybrid tilapia Oreochromis niloticus×Oreochromis aureus. The acidic protease activities increased 65·5 and 55·1% by addition of homogenates of digesta‐containing stomach with copper (75 mg l−1) and zinc (50 mg l−1) respectively. Addition of Cu and Zn increased the activities of protease in the hepatopancreas homogenates by 132·7 and 38·1% respectively, and reduced the activity of protease in the digesta‐containing intestine homogenates by 11·0 and 13·8% respectively. Addition of Fe (50 mg l−1) increased the acidic protease activity by 96·7% but did not alter the activities of protease in the intestine and hepatopancreas. Addition of Cu markedly inhibited activities of amylase in intestine and hepatopancreas homogenates, while Zn addition showed no effects. Addition of Fe reduced activities of amylase in the intestine homogenates by 47·9% but had no effect on amylase activities in the hepatopancreas. When Cu (75 mg kg−1), Fe (50 mg kg−1) and Zn (50 mg kg−1) were supplemented to basal diet for 3 weeks, the activities of amylase in hepatopancreas homogenates increased 125·3, 215·6 and 70·0%, respectively, the activities of amylase in intestine increased 79·8, 74·6 and 48·5%, respectively, and the activities of lipase in intestine increased 90·5, 149·8 and 84·0%, respectively. Supplementation of Cu, Fe or Zn into diet had no effects on activity of protease in all digestive organs. Therefore, the results suggest that effects of Cu, Fe and Zn on activity of digestive enzymes in vitro were different from those seen in vivo, and that the positive effects of Cu, Fe and Zn supplemented to fish diet would be valuable information for formulating fish feed.
Elevated oxygen uptake and high rates of nitrogen excretion in early life stages of the cobia Rachycentron canadum (L.), a fast‐growing subtropical fish
Authors: Feeley M. W. , Benetti D. D. , Ault J. S.
Published: August 2010

Physiological energetics of cobia Rachycentron canadum were quantified for 18 to 82 days post‐hatch (dph) hatchery‐reared juveniles to better understand energy transformation and its implications in growth and survival. Mean oxygen consumption rates (; mg O2 h−1) of fish fed ad libitum and fish that were starved significantly increased with increasing wet mass (M; g), = 1·4291M0·8119 and = 1·1784M0·7833, respectively, with a significant reduction in mean metabolic rates of starved fish (19 to 27% specific dynamic action; SDA). Total ammonia nitrogen excretion rates (AMM, μmol h−1) also scaled with M and significantly decreased after starvation. Mean mass‐specific AMM and urea excretion rates are the highest reported in the literature, with urea accounting for approximately half the total nitrogen excretion measured in both fed and starved fish. Relatively high energetic rates may allow cobia to develop rapidly into pre‐juveniles and be less susceptible to predation and starvation at a comparatively early age.
Sardine early survival, physical condition and stress after introduction to captivity
Authors: Marçalo A. , Pousão‐Ferreira P. , Mateus L. , Duarte Correia J. H. , Stratoudakis Y.
Published: August 2010

The main factors that affect early survival, physical damage and stress reactions of sardine Sardina pilchardus after live capture and introduction to captivity were examined. A total of 2800 sardines were captured alive from commercial purse seiners in five trials off southern Portugal and monitored for 4 weeks in aquaculture tanks. Survival rates varied considerably between trials (from <20 to >80% after a month), with most deaths occurring in the first 5 days. Sardine early survival was affected by factors related to conditions at sea (catch composition, sea temperature and transportation density), during introduction to captivity (magnitude of thermal shock, land transportation duration and use of antibacterial treatment) and, possibly, their interaction. Physical damage was related to the probability of dying, with fish that died during the first week showing significantly higher scale loss and larger caudal fin erosion that those that were alive in the same period. For all stress variables measured (blood haematocrit, cortisol, glucose and ions in the plasma), the most extreme values were attained during introduction to captivity or in the first hours after. After 2 weeks in captivity, most variables had returned to levels close to those observed at the onset of purse‐seine fishing, suggesting that maintenance conditions were adequate to permit a rapid recovery from fishing and transport stress.
Is topmouth gudgeon Pseudorasbora parva responsible for the decline in sunbleak Leucaspius delineatus populations?
Authors: Carpentier A. , Gozlan R. E. , Cucherousset J. , Paillisson J.‐M. , Marion L.
Published: August 2010

In England, a severe decline of introduced sunbleak Leucaspius delineatus populations has been attributed to the introduction of the invasive topmouth gudgeon Pseudorasbora parva. In France, however, after 4 years of P. parva colonization in a large natural lake, no demonstrated impacts on the native L. delineatus populations have been observed. This suggests that the original impacts observed in England, such as spawning inhibition and high mortality, were the result of an emerging pathogen, the rosette‐like agent, hosted by L. delineatus rather than P. parva.
Microhabitat use and interspecific associations of introduced topmouth gudgeon Pseudorasbora parva and native fishes in a small stream
Authors: Beyer K. , Copp G. H. , Gozlan R. E.
Published: August 2010

To address a lack of information on topmouth gudgeon Pseudorasbora parva introduced to watercourses, the microhabitat use of this non‐native cyprinid and co‐existing native species was assessed in a small stream located in southern England. Overall, microhabitat use was size‐structured and significant associations were observed between topmouth gudgeon and native species, including brown trout Salmo trutta, chub Leuciscus cephalus, European bullhead Cottus gobio and stone loach Barbatula barbatula. Significant associations with environmental variables, however, were more frequent in native species than in topmouth gudgeon. Topmouth gudgeon demonstrated few habitat preferences, which were weak and limited to small specimens, emphasizing the species broad, plastic breadth of microhabitat use. This is expected to facilitate the species’ successful invasion of novel aquatic systems.
The non‐indigenous freshwater fishes of Flanders (Belgium): review, status and trends over the last decade
Authors: Verreycken H. , Anseeuw D. , Van Thuyne G. , Quataert P. , Belpaire C.
Published: August 2010

Fourteen non‐indigenous fish species have been successfully introduced to the wild within the territory of Flanders; nine are considered naturalized. Most of the introductions occurred prior to 1950, with six species introduced since then. This paper reviews the available, hitherto scattered, information (including ‘grey literature’) on these 14 non‐indigenous fish species introductions, and evaluates a decade of data from fisheries surveys to assess the recent development of these non‐indigenous populations. Gibel carp Carassius gibelio and topmouth gudgeon Pseudorasbora parva are the most widespread of the non‐indigenous species in Flemish waters, and both continue to expand their ranges. A reduction in range has been observed in brown bullhead Ameiurus nebulosus only. A case is presented for not including European catfish Silurus glanis, sunbleak Leucaspius delineatus and European bullhead Cottus gobio on the list of non‐indigenous freshwater fishes in Flanders. Also discussed are non‐indigenous fish species that are likely to colonize Flanders inland waters in the near future.
Propagule pressure and the invasion risks of non‐native freshwater fishes: a case study in England
Authors: Copp G. H. , Templeton M. , Gozlan R. E.
Published: August 2010

European countries in general, and England in particular, have a long history of introducing non‐native fish species, but there exist no detailed studies of the introduction pathways and propagules pressure for any European country. Using the nine regions of England as a preliminary case study, the potential relationship between the occurrence in the wild of non‐native freshwater fishes (from a recent audit of non‐native species) and the intensity (i.e. propagule pressure) and diversity of fish imports was investigated. The main pathways of introduction were via imports of fishes for ornamental use (e.g. aquaria and garden ponds) and sport fishing, with no reported or suspected cases of ballast water or hull fouling introductions. The recorded occurrence of non‐native fishes in the wild was found to be related to the time (number of years) since the decade of introduction. A shift in the establishment rate, however, was observed in the 1970s after which the ratio of established‐to‐introduced species declined. The number of established non‐native fish species observed in the wild was found to increase significantly (P < 0·05) with increasing import intensity (log10x + 1 of the numbers of fish imported for the years 2000–2004) and with increasing consignment diversity (log10x + 1 of the numbers of consignment types imported for the years 2000–2004). The implications for policy and management are discussed.
Fluctuating asymmetry in the otoliths of larval Atlantic menhaden Brevoortia tyrannus (Latrobe) – a condition indicator?
Authors: Fey D. P. , Hare J. A.
Published: August 2010

Fluctuating asymmetry (FA) was described for otolith length, width and area for two groups of larval and juvenile Atlantic menhaden Brevoortia tyrannus. The larvae and juveniles (age range: 20–120 days; standard length, LS, range: 14–35 mm) were separated into the two distinct groups a priori on the basis of their growth indices estimated from residuals of a LS‐at‐age model; slow growers had residuals <8% of the average size at age and fast growers had residuals >8%. Some indication supporting the fluctuating asymmetry methodology was found when unsigned normalized FA2 index was used for otolith area. That conclusion was not, however, supported by the other method used in this work, i.e. between‐group ANCOVA analysis of individual unsigned and not normalized FA1 indices plotted against trait size. These inconsistent results are most probably a consequence of error introduced during FA index normalization (accounting for trait size effect on absolute FA). Although it is concluded here that FA analysis of sagittal otoliths was not effective in describing differences in the natural variability of growth and condition of larval Atlantic menhaden, the possible species‐ and otolith type‐related differences should be considered in the future research on FA.
Effects of the toxic dinoflagellate, Alexandrium fundyense on three species of larval fish: a food‐chain approach
Authors: Samson J. C. , Shumway S. E. , Weis J. S.
Published: August 2010

Sublethal behavioural effects of exposure to paralytic shellfish toxins (PST; saxitoxin and its derivatives) from the toxic dinoflagellate Alexandrium fundyense were investigated in newly settled winter flounder Pseudopleuronectes americanus, larval sheepshead minnow Cyprinodon variegatus and larval mummichog Fundulus heteroclitus through an A. fundyense–copepod–fish food chain. Consumption of as few as six to 12 toxin‐containing copepods was lethal to the fishes. After consuming fewer toxin‐containing copepods, all three fish species exhibited sublethal effects from vector‐mediated exposure. Prey‐capture ability of mummichogs was reduced in larvae that had consumed toxic copepods, Coullana canadensis. After consuming toxic C. canadensis or mixed copepods, mummichog larvae had reduced swimming performance. Swimming activity was also significantly reduced in winter flounder after consuming toxic copepods, including time spent in motion and distance travelled. Prey capture and predator avoidance were reduced in first‐feeding sheepshead minnow larvae that had consumed toxic dinoflagellate cells. Adverse effects on prey capture or predator avoidance may reduce larval survival and facilitate the transmission of PST through the food web. This study provides baseline information on sublethal effects of PST exposure on fishes using a novel food‐chain approach with zooplankton as vectors.
Variation in clones of the sperm‐dependent parthenogeneticCarassius gibelio(Bloch) in Lake Pamvotis (north‐west Greece)
Authors: Liousia V. , Liasko R. , Koutrakis E. , Leonardos I. D.
Published: August 2010

Variation in three different clones of the invasive sperm‐dependent, cyprinid fishCarassius gibeliowere examined in Lake Pamvotis (north‐west Greece). Differences between the clones were found in their proportion in the population, in their age structure, in the time of arrival to their spawning grounds and in the coefficients of the von Bertalanffy growth equation.
Review of the Australian hagfishes with description of two new species ofEptatretus(Myxinidae)
Authors: Mincarone M. M. , Fernholm B.
Published: August 2010

This paper revises and updates taxonomic and distributional information about hagfishes (Myxinidae) from Australia. It covers five species of the genusEptatretus:Eptatretus cirrhatusknown from eastern Australia and also distributed around New Zealand,Eptatretus longipinnisendemic to South Australia,Eptatretus strahanioriginally described from the Philippines and reported here as a new record from Western Australia and two new species described herein asEptatretus alastairiandEptatretus gomoni, both from Western Australia.Eptatretus alastairiis distinguished from all congeners by the unique combination of the following characters: six pairs of gill pouches; three‐cusp multicusps on the anterior and posterior rows of cusps; anterior unicusps 9–12; posterior unicusps 8–11; total cusps 48–56; prebranchial pores 13–16; branchial pores 5–6; trunk pores 50–55; tail pores 11–13; total pores 83–88; two bilaterally symmetrical nasal‐sinus papillae in the dorsal surface of the nasal sinus.Eptatretus gomoniis distinguished from all congeners by the unique combination of the following characters: eight pairs of gill pouches; three‐cusp multicusps on the anterior and two‐cusp multicusps on the posterior row of cusps; anterior unicusps 10–11; posterior unicusps 9–10; total cusps 50; prebranchial pores 12–13; branchial pores 7–8; trunk pores 57–58; tail pores 14–15; total pores 91–93; no nasal‐sinus papillae. An identification key for the Australian species ofEptatretusis also provided.
Chemical excretions of angled bonefish Albula vulpes and their potential use as predation cues by juvenile lemon sharks Negaprion brevirostris
Authors: Dallas L. J. , Shultz A. D. , Moody A. J. , Sloman K. A. , Danylchuk A. J.
Published: August 2010

Bonefish Albula vulpes (n = 7) exercised to exhaustion and air exposed for 1 min as part of a catch‐and‐release angling event were found to excrete both ammonia and urea, but cortisol and lactate were below detectable levels. Urea made up a greater proportion of total nitrogen excretion from these fish at all time points following an angling event. When captive juvenile lemon sharks Negaprion brevirostris (n = 12) were exposed to a 30 s pulse of these chemicals [ammonia (500 mM), cortisol (20 µg l−1), lactate (6 mM) or urea (3 mM)], they showed a significant reduction in the frequency of resting behaviours when exposed to ammonia and urea than when exposed to control water. It appears that products excreted by A. vulpes, particularly ammonia and urea, may provide an olfactory cue for the post‐release predation of A. vulpes by N. brevirostris during catch‐and‐release angling events.
Empirical support for a multi‐dimensional model of sensations experienced by youth during their initial smoking episodes
Authors: Richardson Chris G. , Okoli Chizimuzo T. C. , Ratner Pamela A. , Johnson Joy L.
Published: August 2010

Aims To examine the dimensionality of sensations experienced during initial tobacco smoking.

Design Cross‐sectional survey.

Setting Thirteen secondary schools located in British Columbia, Canada.

Participants Data from 1187 adolescents who responded ‘yes’ to the question: ‘Have you ever tried cigarette smoking, even one or two puffs?’.

Measurements Participants answered questions about their demographic characteristics, tobacco smoking history and sensations experienced during their initial smoking episodes.

Findings The sensations appear to represent the following three separate but modestly correlated dimensions: a pleasant dimension defined by feeling good and relaxed; an unpleasant dimension defined by coughing, feeling sick and nervous; and a ‘buzz’ dimension defined by feeling high and dizzy. The three factors made statistically significant contributions to the prediction of transition to regular smoking (defined as having smoked at least 100 cigarettes in one's life‐time) after adjusting for age, sex and age at first puff.

Conclusions The results suggest that three relatively distinct physiological systems appear to explain the relationship between initial smoking sensations and probability of becoming a regular smoker. Researchers examining sensations experienced during initial tobacco smoking episodes should consider using a three‐dimensional profile of symptoms composed of pleasant, unpleasant and buzz dimensions.
Meta‐analysis: isosorbide‐mononitrate alone or with either beta‐blockers or endoscopic therapy for the management of oesophageal varices
Authors: Gluud L. L. , Langholz E. , Krag A.
Published: August 2010

Aliment Pharmacol Ther 2010; 32: 859–871

Background  The evidence concerning the use of isosorbide‐mononitrate (IsMn) for oesophageal varices is equivocal.

Aim  To assess the effects of IsMn for patients with oesophageal varices and no previous bleeding (primary prevention) or previous variceal bleeding (secondary prevention).

Methods  Systematic review with meta‐analyses of randomized trials on IsMn alone or with beta‐blockers or endoscopic therapy for oesophageal varices. Electronic and manual searches were combined. Randomized trials on primary and secondary prevention were included. The primary outcome measure was mortality. Intention‐to‐treat random effects meta‐analyses were performed. The robustness of the results was assessed in trial sequential analyses.

Results  Ten randomized trials on primary and 17 on secondary prevention were included. Evidence of bias was identified. No apparent effect of IsMn on mortality compared with placebo or beta‐blockers or IsMn plus beta‐blockers vs. beta‐blockers was identified. Compared with endoscopic therapy, IsMn plus beta‐blockers had no apparent effect on bleeding, but did seem to reduce mortality in secondary prevention (RR 0.73, 95% CI 0.59–0.89), but not in primary prevention. The effect of IsMn plus beta‐blockers on mortality in secondary prevention was not confirmed in trial sequential analysis.

Conclusions  Isosorbide‐mononitrate used alone or in combination with beta blockers does not seem to offer any reduction in bleeding in the primary or secondary prevention of oesophageal varices. Compared with endoscopic therapy, there may be a survival advantage in using IsMn and beta‐blockers, but additional large multicentre trials are needed to verify this finding.
Review article: gene therapy, recent developments and future prospects in gastrointestinal oncology
Authors: Touchefeu Y. , Harrington K. J. , Galmiche J. P. , Vassaux G.
Published: August 2010

Aliment Pharmacol Ther 2010; 32: 953–968

Background  Gene therapy consists of the introduction of genetic material into cells for a therapeutic purpose. A wide range of gene therapy vectors have been developed and used for applications in gastrointestinal oncology.

Aim  To review recent developments and published clinical trials concerning the application of gene therapy in the treatment of liver, colon and pancreatic cancers.

Methods  Search of the literature published in English using the PubMed database.

Results  A large variety of therapeutic genes are under investigation, such as tumour suppressor, suicide, antiangiogenesis, inflammatory cytokine and micro‐RNA genes. Recent progress concerns new vectors, such as oncolytic viruses, and the synergy between viral gene therapy, chemotherapy and radiation therapy. As evidence of these basic developments, recently published phase I and II clinical trials, using both single agents and combination strategies, in adjuvant or advanced disease settings, have shown encouraging results and good safety records.

Conclusions  Cancer gene therapy is not yet indicated in clinical practice. However, basic and clinical advances have been reported and gene therapy is a promising, new therapeutic approach for the treatment of gastrointestinal tumours.
The performance of a novel ball‐tipped Flush knife for endoscopic submucosal dissection: a case–control study
Authors: Toyonaga T. , Man‐I M. , Fujita T. , Nishino E. , Ono W. , Morita Y. , Sanuki T. , Masuda A. , Yoshida M. , Kutsumi H. , Inokuchi H. , Azuma T.
Published: August 2010

Aliment Pharmacol Ther 2010; 32: 908–915

Background  Endoscopic submucosal dissection (ESD) using short needle knives is safe and effective, but bleeding is a problem due to low haemostatic capability.

Aim  To assess the performance of a novel ball‐tipped needle knife (Flush knife‐BT) for ESD with particular emphasis on haemostasis.

Methods  A case–control study to compare the performance for ESD of 30 pairs of consecutive early gastrointestinal lesions (oesophagus: 12, stomach: 32, colorectum: 16) with standard Flush knife (F) vs. Flush knife‐BT (BT). Primary outcome was efficacy of intraprocedure haemostasis. Secondary outcomes included procedure time, procedure speed (dividing procedure time into the area of resected specimen), en bloc resection rate and recurrence rate.

Results  Median intraoperative bleeding points and bleeding points requiring haemostatic forceps were smaller in the BT group than in the F group (4 vs. 8, P < 0.0001, 0 vs. 3, P < 0.0001). There was no difference between groups for procedure time; however, procedure speed was shorter in the BT group (P = 0.0078). En bloc and en bloc R0 resection rates were 100%, with no perforation or post‐operative bleeding. No recurrence was observed in either group at follow‐up 1 year postprocedure.

Conclusions  Ball‐tipped Flush knife (Flush knife‐BT) appears to improve haemostatic efficacy and dissection speed compared with standard Flush knife.
Meta‐analysis: re‐treatment of genotype I hepatitis C nonresponders and relapsers after failing interferon and ribavirin combination therapy
Authors: Singal A. G. , Waljee A. K. , Shiffman M. , Bacon B. R. , Schoenfeld P. S.
Published: August 2010

Aliment Pharmacol Ther 2010; 32: 969–983

Background  The efficacy of re‐treating genotype I hepatitis C virus (HCV) patients who failed combination therapy with interferon/pegylated interferon (PEG‐IFN) and ribavirin remains unclear.

Aims  To quantify sustained virological response (SVR) rates with different re‐treatment regimens through meta‐analysis of randomized controlled trials (RCTs).

Methods  Randomized controlled trials of genotype I HCV treatment failure patients that compared currently available re‐treatment regimens were selected. Two investigators independently extracted data on patient population, methods and results. The pooled relative risk of SVR for treatment regimens was computed using a random effects model.

Results  Eighteen RCTs were included. In nonresponders to standard interferon/ribavirin, re‐treatment with high‐dose PEG‐IFN combination therapy improved SVR compared with standard PEG‐IFN combination therapy (RR = 1.49; 95% CI: 1.09–2.04), but SVR rates did not exceed 18% in most studies. In relapsers to standard interferon/ribavirin, re‐treatment with high‐dose PEG‐IFN or prolonged CIFN improved SVR (RR = 1.57; 95% CI: 1.16–2.14) and achieved SVR rates of 43–69%.

Conclusions  In genotype I HCV treatment failure patients who received combination therapy, re‐treatment with high‐dose PEG‐IFN combination therapy is superior to re‐treatment with standard combination therapy, although SVR rates are variable for nonresponders (≤18%) and relapsers (43–69%). Re‐treatment may be appropriate for select patients, especially relapsers and individuals with bridging fibrosis or compensated cirrhosis.
The effects of high‐dose esomeprazole on gastric and oesophageal acid exposure and molecular markers in Barrett’s oesophagus
Authors: Abu‐Sneineh A. , Tam W. , Schoeman M. , Fraser R. , Ruszkiewicz A. R. , Smith E. , Drew P. A. , Dent J. , Holloway R. H.
Published: August 2010

Aliment Pharmacol Ther 2010; 32: 1023–1030

Background  Acid reflux is often difficult to control medically.

Aim  To assess the effect of 40 mg twice daily esomeprazole (high‐dose) on gastric and oesophageal pH and symptoms, and biomarkers relevant to adenocarcinoma, in patients with Barrett’s oesophagus (BO).

Methods  Eighteen patients, treated with proton pump inhibitors as prescribed by their treating doctor, had their therapy increased to high‐dose esomeprazole for 6 months.

Results  At entry into the study, 9/18 patients had excessive 24‐h oesophageal acid exposure, and gastric pH remained <4 for >16 h in 8/18. With high‐dose esomeprazole, excessive acid exposure occurred in 2/18 patients, and gastric pH <4 was decreased from 38% of overall recording time and 53% of the nocturnal period to 15% and 17%, respectively (P < 0.001). There was a reduction in self‐assessed symptoms of heartburn (P = 0.0005) and regurgitation (P < 0.0001), and inflammation and proliferation in the Barrett’s mucosa. There was no significant change in p53, MGMT or COX‐2 expression, or in aberrant DNA methylation.

Conclusions  High‐dose esomeprazole achieved higher levels of gastric acid suppression and control of oesophageal acid reflux and symptoms, with significant decreases in inflammation and epithelial proliferation. There was no reversal of aberrant DNA methylation.
Epidemiology and risk factors for drug allergy
Authors: Thong Bernard Y‐H. , Tan Teck‐Choon
Published: August 2010

The aim of this review was to describe the current evidence‐based knowledge of the epidemiology, prevalence, incidence, risk factors and genetic associations of drug allergy. Articles published between 1966 and 2010 were identified in MEDLINE using the key words adult, adverse drug reaction reporting systems, age factors, anaphylactoid, anaphylaxis, anaesthetics, antibiotics, child, drug allergy, drug eruptions, ethnic groups, hypersensitivity, neuromuscular depolarizing agents, neuromuscular nondepolarizing agents, sex factors, Stevens Johnson syndrome and toxic epidermal necrolysis. Additional studies were identified from article reference lists. Relevant, peer‐reviewed original research articles, case series and reviews were considered for review. Current epidemiological studies on adverse drug reactions (ADRs) have used different definitions for ADR‐related terminology, often do not differentiate immunologically and non‐immunologically mediated drug hypersensitivity, study different study populations (different ethnicities, inpatients or outpatients, adults or children), utilize different methodologies (spontaneous vs. non‐spontaneous reporting, cohort vs. case‐control studies), different methods of assessing drug imputability and different methods of data analyses. Potentially life‐threatening severe cutaneous adverse reactions (SCAR) are associated with a high risk of morbidity and mortality. HLA associations for SCAR associated with allopurinol, carbamazepine and abacavir have been reported with the potential for clinical use in screening prior to prescription. Identification of risk factors for drug allergy and appropriate genetic screening of at‐risk ethnic groups may improve the outcomes of drug‐specific SCAR. Research and collaboration are necessary for the generation of clinically‐relevant, translational pharmacoepidemiological and pharmacogenomic knowledge, and success of health outcomes research and policies on drug allergies.
Quantifying the benefits and costs of parental care in assassin bugs
Authors: GILBERT JAMES D. J. , THOMAS LISA K. , MANICA ANDREA
Published: August 2010

1. Which sex should care for offspring depends on the cost and benefits of the behaviour for each sex. Understanding these differences between the sexes is a fundamental step to explain the evolution of animal societies, but it is often difficult to quantify them empirically. A possible approach is to investigate two closely related species that perform a very similar type of care but in which the caring sex differs.

2. Using field and laboratory data, we estimated the benefits and costs of parental care in two species of assassin bugs with very similar ecologies: Rhinocoris tristis, which has exclusive paternal care, and Rhinocoris carmelita, which has exclusive maternal care.

3. In both species, the main benefit of care was a reduction in parasitism and predation of eggs. Guarding R. tristis males consumed eggs (filial cannibalism), and thus managed not to lose weight, but R. carmelita females paid the full energetic cost of care. Guarding male R. tristis incurred survival costs relative to non‐guarding male and female conspecifics.

4. Very high population density and female preference for males already guarding eggs (a preference previously recorded in fish) minimised the promiscuity cost of paternal care in R. tristis, explaining the difference in care pattern between the two species.
Active matrix metalloproteinase‐2 upregulation in the abdominal skin of patients with direct inguinal hernia
Authors: Pascual Gemma , Rodríguez Marta , Gómez‐Gil Verónica , Trejo Cynthia , Buján Julia , Bellón Juan Manvel
Published: August 2010

Eur J Clin Invest 2010; 40 (12): 1113–1121

Background  Prior studies suggest impaired collagen metabolism involving the whole abdominal wall including the skin in patients with abdominal hernia. We compared expression patterns of matrix metalloproteinase‐2 (MMP‐2) and its modulators membrane type‐1‐matrix metalloproteinase (MT‐1 MMP) and tissue inhibitor of metalloproteinase‐2 (TIMP‐2) in the skin of patients with and without primary inguinal hernia.

Materials and methods  Skin biopsy specimens from abdominal wall incisions were obtained during surgery from patients with direct inguinal hernia, indirect inguinal hernia or without hernia (controls). MMP‐2, MT‐1 MMP and TIMP‐2 expression were determined using immunocytochemistry and immunoblotting in intact tissue and in cultured fibroblasts isolated from the biopsies. The degradation activity of MMP‐2 was semiquantitatively determined using zymography.

Results  Significantly greater active MMP‐2 expression was observed in skin fibroblasts obtained from patients with direct hernia compared with controls. MT1‐MMP expression was directly correlated with MMP‐2 expression with most intense staining produced in patients with direct or indirect inguinal hernia. TIMP‐2, was maximally expressed in the control group, with significantly diminished expression levels recorded in the hernia groups.

Conclusions  Our findings indicate active MMP‐2 upregulation in the abdominal skin of patients with direct inguinal hernia. This metalloproteinase plays a role in matrix degradation, weakening the abdominal wall. Skin disorders and previously described transversalis fascia defects in these patients could point to a systemic collagen metabolism abnormality as a risk factor for direct hernia.
Annual balances of CH4 and N2O from a managed fen meadow using eddy covariance flux measurements
Authors: Kroon P. S. , Schrier‐Uijl A. P. , Hensen A. , Veenendaal E. M. , Jonker H. J. J.
Published: August 2010

Annual terrestrial balances of methane (CH4) and nitrous oxide (N2O) are presented for a managed fen meadow in the Netherlands for 2006, 2007 and 2008, using eddy covariance (EC) flux measurements. Annual emissions derived from different methods are compared. The most accurate annual CH4 flux is achieved by gap filling EC fluxes with an empirical multivariate regression model, with soil temperature and mean wind velocity as driving variables. This model explains about 60% of the variability in observed daily CH4 fluxes. Annual N2O emissions can be separated into background emissions and event emissions due to fertilization. The background emission is estimated using a multivariate regression model also based on EC flux data, with soil temperature and mean wind velocity as driving variables. The event emissions are estimated using emission factors. The minimum direct emission factor is derived for six fertilization events by subtracting the background emission, and the IPCC default emission factor of 1% is used for the other events. In addition, the maximum direct emission factors are determined for the six events without subtracting the background emission. The average direct emission factor ranges from 1.2 to 2.8%, which is larger than the IPCC default value. Finally, the total terrestrial greenhouse gas balance is estimated at 16 Mg ha−1 year−1 in CO2‐equivalents with contributions of 30, 25 and 45% by CO2, CH4 and N2O, respectively.
Greenhouse gas emissions from European soils under different land use: effects of soil moisture and temperature
Authors: Schaufler G. , Kitzler B. , Schindlbacher A. , Skiba U. , Sutton M. A. , Zechmeister‐Boltenstern S.
Published: August 2010

In order to estimate potential greenhouse gas flux rates from soils under different land use and climate, and to particularly assess the influence of soil temperature and soil moisture, we measured fluxes of nitrous oxide (N2O), nitric oxide (NO), carbon dioxide (CO2) and methane (CH4) from intact soil cores obtained from 13 European sites under controlled laboratory conditions. The soils covered the different climates of Europe and included four different land‐use types: croplands, forests, grasslands and wetlands. In a two‐factorial experimental design, the soil cores were incubated under four temperatures (5–20°C) and water contents (20–80% water‐filled pore space). We found a non‐linear increase of N2O, NO and CO2 emissions with increasing temperature. Nitrous oxide emissions were positively correlated with soil moisture, while NO emission and CH4 oxidation rates were negatively correlated with soil moisture. Maximum CO2 emissions occurred at intermediate soil moisture.

Different land‐use types strongly affected greenhouse gas fluxes. Nitrous oxide and CO2 emissions were highest in grassland soils, while NO emissions were highest in forest soils. In grasslands, high soil microbial activity stimulated by high carbon (C) and nitrogen (N) contents, dense root systems and high C input from above‐ground decaying biomass was the most likely cause for high N2O and CO2 emissions. High NO emissions from forest soils were mainly attributed to low pH and high soil porosity. Northern soils showed the greatest capacity to take up CH4 under warmer and dryer soil conditions. Nitric oxide emissions were positively correlated with N input.
Does haemophilia influence cancer‐related mortality in HIV‐negative patients?
Authors: MIESBACH W. , SEIFRIED E.
Published: August 2010

Summary.  Clinical investigations and animal studies suggest haemophilia specific effects on cancer‐related mortality aside from virus induced malignancies. Analysis of results in the literature proposes that coagulation factor deficiency might inhibit cancer metastasis through decreased activation of thrombin. On the other hand, substitution of coagulation factor might increase cancer rates. A review of epidemiological studies was conducted to survey the clinical data on cancer rates. Clinical investigations concerning cancer‐related mortality in haemophilia always deal with virus‐related malignancies caused by HIV and/or hepatitis C virus (HCV) infections. Therefore, analysis of cancer rates and standardized mortality ratios (SMR) of cancer in the literature was conducted under exclusion of HIV infection and concomitant malignancies like non‐Hodgkin‐lymphomas and under exclusion of HCV‐related deaths caused by liver disease and hepatocellular carcinoma. The survey covers epidemiological studies which report causes of deaths of more than 8000 haemophilia patients, including more than 2700 HIV‐negative patients. Results show virus independent cancer rates of 8–16% of deaths. Analysis of corresponding SMRs supports the hypothesis that cancer rates, unaffected through HIV or hepatoma, are decreased in haemophilia when compared with the general population. Prospective data collection regarding factor consumption as well as severity of haemophilia in virus negative cancer patients is needed to investigate the interaction between haemophilia and cancer.