bluuebunny/crossref_metadata_2025 huggingface dataset:
Advanced Glycation Endproducts Induce Photocrosslinking and Oxidation of Bovine Lens Proteins Through Type‐I Mechanism
Authors: Fuentealba Denis , Friguet Bertrand , Silva Eduardo
Published: July 2008

Advanced glycation endproducts (AGEs) have been suggested as photosensitizers that are capable of mediating eye lens photo‐damage during aging. In the present work, we investigate the photo‐crosslinking and oxidation of bovine lens proteins sensitized by AGEs, with special regard to low oxygen conditions. A mechanistic study was conducted using different oxygen concentrations and specific additives with the aim either to scavenge or enhance Type‐I or Type‐II photoprocesses. Quantum yields for Trp decomposition were determined at 5%, 20% and 100% O2, in the presence of ferricyanide and D2O to elucidate the mechanism of action of AGEs. Type‐I mechanism proved to be the most efficient pathway for AGE‐sensitized Trp decomposition at low oxygen concentration. Photocrosslinking of lens proteins and crystallin fractions due to Type‐I interaction was observed. The influence of the oxygen concentration and additives was also studied. The results show that both Type‐I mechanism and oxygen‐mediated reactions contribute to protein crosslinking. Carbonyl group formation due to protein photo‐oxidation was detected with Oxyblot technique. The generation of high levels of hydrogen peroxide during the irradiations was detected and attributed mainly to Type‐I reactions. The results support that AGEs act preferentially as Type‐I sensitizers at the low oxygen concentration found in the lens and are capable of inducing protein crosslinking, oxidation and peroxide formation.
Resveratrol: A Natural Compound with Pharmacological Potential in Neurodegenerative Diseases
Authors: Rocha‐González Héctor I. , Ambriz‐Tututi Mónica , Granados‐Soto Vinicio
Published: July 2008

Resveratrol is a phytoalexin structurally related to stilbenes, which is synthesized in considerable amounts in the skin of grapes, raspberries, mulberries, pistachios and peanuts, and by at least 72 medicinal and edible plant species in response to stress conditions. It was isolated in 1940 and did not maintain much interest for around five decades until its role in treatment of cardiovascular diseases was suggested. To date, resveratrol has been identified as an agent that may be useful to treat cancer, pain, inflammation, tissue injury, and other diseases. However, currently the attention is being focused in analyzing its properties against neurodegenerative diseases and as antiaging compound. It has been reported that resveratrol shows effects inin vitromodels of epilepsy, Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, and nerve injury. However, evidencesin vivoas well as in human beings are still lacking. Thus, further investigations on the pharmacological effects of resveratrolin vivoare necessary before any conclusions on its effects on neurodegenerative diseases can be obtained.
Seroprevalence and Risk Factors for Influenza A Viruses in Pigs in Peninsular Malaysia
Authors: Suriya R. , Hassan L. , Omar A. R. , Aini I. , Tan C. G. , Lim Y. S. , Kamaruddin M. I.
Published: July 2008

Following a series of H5N1 cases in chickens and birds in a few states in Malaysia, there was much interest in the influenza A viruses subtypes that circulate among the local pig populations. Pigs may act as a mixing vessel for avian and mammal influenza viruses, resulting in new reassorted viruses. This study investigated the presence of antibodies against influenza H1N1 and H3N2 viruses in pigs from Peninsular Malaysia using Herdcheck Swine Influenza H1N1 and H3N2 Antibody Test Kits. At the same time, the presence of influenza virus was examined from the nasal swabs of seropositive pigs by virus isolation and real time RT‐PCR. The list of pig farms was obtained from the headquarters of the Department of Veterinary Services, Malaysia, and pig herds were selected randomly from six of 11 states in Peninsular Malaysia. A total of 727 serum and nasal swab samples were collected from 4‐ to 6‐month‐old pigs between May and August 2005. By ELISA, the seroprevalences of swine influenza H1N1 and H3N2 among pigs were 12.2% and 12.1% respectively. Seropositivity for either of the virus subtypes was detected in less than half of the 41 sampled farms (41.4%). Combination of both subtypes was detected in 4% of all pigs and in 22% of sampled farms. However, no virus or viral nucleic acid was detected from nasal samples. This study identified that the seropositivity of pigs to H1N1 and H3N2 based on ELISA was significantly associated with factors such as size of farm, importation or purchase of pigs, proximity of farm to other pig farms and the presence of mammalian pets within the farm.
Effect of the Dimethoate Administration on a Scrapie Murine Model
Authors: Hortells P. , Monleón E. , Acín C. , Vargas A. , Ryffel B. , Cesbron J. Y. , Badiola J. J. , Monzón M.
Published: July 2008

Some authors have associated organophosphate compounds with susceptibility to transmissible spongiform encephalopathy (TSE) and even with the origin of this group of diseases. Nevertheless, the actual role played by these compounds still remains unclear. The aim of this study was to assess the effect of oral exposure to dimethoate (DMT) on the development of Scrapie using a genetically modified murine model. A total of 70 C57BL/6 mice over‐expressing the PrP gene (Tg20) were included in the present study. A portion of the mice were intraperitoneally inoculated, while the rest were maintained as non‐infected controls. Animals from the treated group were exposed to dimethoate dissolved in drinking water from the beginning of the experiment. Variables of incubation period, spongiosis, PrPsc deposits, glial over‐expression, neuronal loss, and amyloid plaques were assessed in all animals. According to the results, a treatment consisting of a daily 15 mg/kg dose of DMT for 5 weeks did not show any effect on any of the variables assessed. Although more exhaustive studies for assessing different doses and organic compounds are required, this finding constitutes an empirical study that rules out the possibility that this compound may have a predisposing effect on TSEs.
The Transmission of Thermotolerant Campylobacter spp. to People Living or Working on Dairy Farms in New Zealand
Authors: Gilpin B. J. , Scholes P. , Robson B. , Savill M. G.
Published: July 2008

New Zealand has one of the highest rates of campylobacteriosis in the developed world with an incidence rate of 383.5 cases per 100 000 in 2006. Dairy farming has been suggested as a potential source of campylobacteriosis. To explore this connection, seven farm investigations were undertaken at dairy farms on which a campylobacteriosis case had been notified. Campylobacter spp. were isolated from a range of sources on the farm (including 66% of bovine faecal samples) and genotypes compared with that of the clinical isolate of the index case. In depth, epidemiological questionnaires were also administered to determine exposure risks from a wide range of possible sources. Contact with dairy cow faeces was the most likely source of infection in four of the seven cases investigated, and occurred exclusively in new farm workers and children. In one of the cases investigated, infection was likely to have been acquired from non‐dairy related sources, and in two cases the source could not be determined. The relative risk of dairy farm worker being notified with campylobacteriosis was estimated to be 1.88 (95% confidence interval = 1.6–2.2).
Serological Evidence of USUTU Virus Occurrence in North‐Eastern Italy
Authors: Lelli R. , Savini G. , Teodori L. , Filipponi G. , Di Gennaro A. , Leone A. , Di Gialleonardo L. , Venturi L. , Caporale V.
Published: July 2008

In the recent years, USUTU virus (USUV), a flavivirus of the Japanese encephalitis virus complex, has been reported in Central Europe. As part of a systematic surveillance programme to monitor possible entrance and/or circulation of vector‐borne viruses, since 2001, sentinel‐chicken flocks were placed throughout the Italian territory nearby areas considered at risk of virus introduction. They have been periodically checked for the presence of antibodies against flaviviruses by indirect ELISA, plaque reduction neutralization test for USUTU, West Nile and tick‐borne encephalitis viruses. In July 2007, a sentinel chicken in a flock of 20 animals located within the Ravenna province seroconverted to USUV reaching neutralizing titres up to 1 : 5120. A second chicken seroconverted to the same virus 2 months later. Although no virus was rescued from these animals and from wild or farm birds sampled in the area, these results still provided evidence of the circulation of USUV in north‐eastern Italy.
γδT Cells Initiate Acute Inflammation and Injury in Adenovirus-Infected Liver via Cytokine-Chemokine Cross Talk
Authors: Ajuebor Maureen N. , Jin Yijun , Gremillion Griffin L. , Strieter Robert M. , Chen Qingling , Adegboyega Patrick A.
Published: July 2008

Emerging studies suggest an important role for the innate immune response in replication-defective adenovirus (Ad)-mediated acute liver toxicity. Specifically, classical innate immune cells (including NK cells, neutrophils, and Kupffer cells) have all been implicated in the development of Ad-mediated acute liver toxicity. The nonclassical innate immune T cell, the γδT cell, has been implicated in the pathophysiology of several viral infections that predominantly affect the mucosa and brain, but the specific role in the pathology of AdLacZ-mediated acute liver inflammation and injury as well as accompanying vector clearance is largely unknown. In the present study, we demonstrated that a CXCL9-CXCR3-dependent mechanism governed the accumulation of γδT cells in the livers of mice infected with Ad expressing theEscherichia coliLacZ gene (AdLacZ). We also showed a critical role for γδT cells in initiating acute liver toxicity after AdLacZ administration, driven in part by the ability of γδT cells to promote the recruitment of the conventional T cell, the CD8+T cell, into the liver. Furthermore, reduced hepatic injury in AdLacZ-infected γδT-cell-deficient mice was associated with lower hepatic levels of gamma interferon (IFN-γ) and CXCL9, an IFN-γ-inducible chemokine. Finally, our study highlighted a key role for IFN-γ and CXCL9 cross talk acting in a feedback loop to drive the proinflammatory effects of γδT cells during AdLacZ-mediated acute liver toxicity. Specifically, intracellular IFN-γ produced by activated hepatic γδT cells interacts with hepatocytes to mediate hepatic CXCL9 production, with the consequent accumulation of CXCR3-bearing γδT cells in the liver to cause acute liver damage without vector clearance.
A two-year sonographic follow-up after intratendinous injection therapy in patients with tennis elbow: Figure 1a–e
Authors: Zeisig E , Fahlström M , Öhberg L , Alfredson H
Published: July 2008

Background

Tennis elbow is a tendinopathy affecting the upper extremity. Recent studies have shown high sensitivity for ultrasound (US) examination and high specificity for colour Doppler (CD) examination. There are no mid- or long-term follow-up investigations of the tendon structure and blood flow using these techniques.

Objective

To use US and CD to study structure and blood flow in the extensor origin in patients with tennis elbow treated with intratendinous injections.

Design

Follow-up study

Setting

Sports Medicine Unit, Umeå University.

Patients

25 patients (28 elbows), mean age 46 years (range 27–66), treated with intratendinous injections due to chronic pain from tennis elbow.

Method

US and CD examination of the extensor origin was carried out at inclusion and at follow-up two years after intratendinous injection treatment with polidocanol and/or a local anaesthetic.

Main outcome measurements

US (structure) and CD (blood flow) findings.

Results

All patients had structural tendon changes and high blood flow at inclusion when given the injection treatment. At the two-year follow-up, structural tendon changes were seen in 20/28 elbows and high blood flow was seen in 4/28 elbows. The majority of patients with a good clinical result after treatment had no visible blood flow (17/20), but the structural changes showed no relation to a good result (13/20 remaining changes).

Conclusions

Doppler findings, but not structure, might be related to the clinical result after intratendinous injection treatment of tennis elbow.
Ethical dilemmas in palliative care in traditional developing societies, with special reference to the Indian setting
Authors: Chaturvedi S K
Published: July 2008

Background:

There are intriguing and challenging ethical dilemmas in the practice of palliative care in a traditional developing society.

Objective:

To review the different ethical issues involved in cancer and palliative care in developing countries, with special reference to India.

Methods:

Published literature on pain relief and palliative care in the developing countries was reviewed to identify ethical issues and dilemmas related to these, and ways in which ethical principles could be observed in delivery of palliative care in such countries are discussed.

Results:

The literature review revealed a number of ethical dilemmas and challenges that professionals, cancer patients and their families encountered during palliative care. It was noted that patients’ preferences and decisions are influenced by family members. Dilemmas leave the professionals and families confused about how ethical their actions have been. Specific ethical issues were noted in relation to the availability and use of oral morphine for pain relief, spiritual care, lack of adequate palliative care services, and palliative care education.

Conclusions:

The four principles of ethics posed difficulties in understanding the complex ethical issues in a developing country with a traditional background. Ethical issues need to be handled delicately and sensitively in palliative care settings, within the framework of the traditions and culture of the society and financial constraints. The possible role of ethics committees in palliative care settings to help decision-making needs to be studied and discussed.
Lives in a chiaroscuro. Should we suspend the puberty of children with gender identity disorder?
Authors: Giordano S
Published: July 2008

Transgender children who are not treated for their condition are at high risk of violence and suicide. As a matter of survival, many are willing to take whatever help is available, even if this is offered by illegal sources, and this often traps them into the juvenile criminal system and exposes them to various threats. Endocrinology offers a revolutionary instrument to help children/adolescents with gender identity disorder: suspension of puberty. Suspension of puberty raises many ethical issues, and experts dissent as to when treatment should be commenced and how children should be followed up. This paper argues that suspension of puberty is not only not unethical: if it is likely to improve the child’s quality of life and even save his or her life, then it is indeed unethical to defer treatment.
The retention of forensic DNA samples: a socio-ethical evaluation of current practices in the EU
Authors: Van Camp N , Dierickx K
Published: July 2008

Since the mid-1990s most EU Member States have established a national forensic DNA database. These mass repositories of DNA profiles enable the police to identify DNA stains which are found at crime scenes and are invaluable in criminal investigation. Governments have always brushed aside privacy objections by stressing that the stored DNA profiles do not contain sensitive genetic information on the included individuals and that they reside under the statutory privacy protection regulations. However, it has been generally overlooked that the police also store the DNA samples from which the DNA profiles are derived. Although these DNA samples are actually a potential source of genetic information, they have so far scarcely been the subject of discussion. In this article we will show that both European and national regulations offer inadequate protection to completely prevent function creep, that is, the use of these forensic DNA samples for purposes beyond those envisaged at the time of collection.
Gender “tailored” conceptions: should the option of embryo gender selection be available to infertile couples undergoing assisted reproductive technology?
Authors: Merhi Z O , Pal L
Published: July 2008

The purpose of this article is to ascertain and appraise the ethical issues inherent to the utilisation of preimplantation genetic diagnosis for gender selection in infertile patients anticipating undergoing a medically indicated assisted reproductive technique procedure. Performance of preimplantation genetic diagnosis per request specifically for gender selection by an infertile couple undergoing medically indicated assisted reproductive technique may not breach the principles of ethics, and is unlikely to alter the population balance of sexes.
Moral–psychological development related to the capacity of adolescents and elderly patients to consent
Authors: Raymundo M M , Goldim J R
Published: July 2008

Objective:

To evaluate moral development as an indicator of the capacity to consent among two groups of patients from the Hospital de Clínicas in Porto Alegre, RS, Brazil.

Method:

Fifty-nine adolescents and 60 patients over 60 years of age participated in a cross-sectional study to assess moral development using Loevinger’s model of ego stages.

Results:

Age and moral development showed no association, with most participants in the two groups being in the conscientious phase.

Conclusions:

Age is probably not an adequate variable to measure decision-making capacity, because questions of medical consent relate to participants’ own personal health. Decision-making capacity should be viewed as a continuous function. While the age of the person whose consent is needed should be considered, age alone, from a moral perspective, is not the main determinant of this capacity.
Evaluating ethics consultation: randomised controlled trial is not the right tool
Authors: Chen Y-Y , Chen Y-C
Published: July 2008

Background:

Although ethics consultation has been introduced to clinical practice for many years, the results of empirical studies to evaluate the effectiveness of ethics consultation are still controversial. The design of randomised controlled trials is considered the best research design to evaluate the effect of a clinical practice on the outcomes of interests. In order to understand the effects of ethics consultation, we conducted this search for studies with the design of randomised controlled trials to evaluate ethics consultation.

Objective:

To provide an integrated review of studies with the design of randomised controlled trials to evaluate the effectiveness of ethics consultation.

Methods:

PubMed was used to search for studies using the randomised controlled trial design to evaluate the effectiveness of ethics consultation. The search term used was “ethics consultation”. The selection criterion was limited to “randomised controlled trial”.

Results:

Four articles that met both search criteria were retrieved. One of these articles reported a study that did not actually use the design of a randomised controlled trial and is excluded from the following discussion.

Conclusions:

To apply randomised controlled trials to evaluate the effectiveness of ethics consultation is extremely difficult as long as two issues are not resolved: the standardisation of ethics consultation and a placebo for ethics consultation to eliminate the placebo effect. Thus, the results generated by the design of randomised controlled trials are always problematic. Furthermore, as long as the two issues exist, the results generated by the design of quantitative research methods always pose problems.
Should research ethics committees meet in public?
Authors: Sheehan M
Published: July 2008

Currently, research ethics committees (RECs) in the UK meet behind closed doors—their workings and most of the content of their decisions are unavailable to the general public. There is a significant tension between this current practice and a broader societal presumption of openness. As a form of public institution, the REC system exists to oversee research from the perspective of society generally.

An important part of this tension turns on the kind of justification that might be offered for the REC system. In this paper I adapt Daniels and Sabin’s accountability for reasonableness model for just resource allocation to the research ethics context to provide some structural legitimacy and to enable progress on the question of openness. After considering the consequences of adopting this model for open REC meetings, I then examine some reasons that might be offered against open meetings. These arguments do not overwhelm the core intuitions behind the presumption of openness but they do, I suggest, give us reason to retreat from fully public meetings. I conclude that there should be important adjustments to the system towards public accountability and that there are grounds for stopping short of fully public meetings.
Ecology of parasitism of Brown-headed Cowbirds by haematozoa
Authors: Weatherhead Patrick J. , Bennett Gordon F.
Published: July 2008

We quantified haematozoa infections in 964 Brown-headed Cowbirds (Molothrus ater) sampled over three summers in eastern Ontario. Our objective was to use the cowbird–haematozoa system to assess practical and theoretical aspects of testing Hamilton and Zuk's parasite hypothesis of sexual selection. We found that most individuals resampled within and between years were consistently scored as parasitized or unparasitized, although some individuals changed status, including going from parasitized to unparasitized. Many hatching-year birds were parasitized, which suggests substantial early exposure to parasites. Significant variation within and between years in general parasite prevalence, specific parasite prevalence, and intensity of infections indicated that population estimates of parasitism would be highly dependent on when birds were sampled and on the age and sex composition of the sample. Analysis of body condition and within-season recapture patterns indicated that parasitism did not have a negative effect on the health of cowbirds. Parasitized birds were also recaptured at the same rate as unparasitized birds between years, indicating that there were no viability effects due to parasitism. Our results suggest a number of pitfalls, some of which are potentially critical, to using haematozoa infections in passerines to test the Hamilton and Zuk hypothesis.
Foraging dynamics of lions in a semi-arid environment
Authors: Stander P. E.
Published: July 2008

Direct observations on the foraging activities of lions, based on 920 attempts to capture prey and 156 kills, on the plains of Etosha National Park, Namibia, revealed a regular nocturnal pattern of mostly coordinated group hunting. Lions scavenged rarely and killed mainly prey animals weighing less than 50 kg, which contributed to 73% of the observed kills and 50% of the estimated biomass consumed. Capture success increased with lion group size and was also greater during coordinated group hunts. Lions hunted most of the prey that they encountered, showing a preference for large prey species. Average food acquisition ranged from 8.7 kg/day per lioness in the dry season to 14 kg/day per lioness in the wet season. During the dry season, coordinated cooperative hunting was essential and lionesses most often formed groups of 2, thereby acquiring higher daily food intake than groups of other sizes. In the wet season, lioness groups of all sizes obtained more than the estimated daily requirements, and lionesses did not uniformly forage in the smaller groups capable of greater food acquisition.
Effects of photoperiod and different intensities of light exposure on melatonin levels in the blood, pineal organ, and retina of the brook trout (Salvelinus fontinalis Mitchill)
Authors: Zachmann A. , Knijff S. C. M. , Ali M. A. , Anctil M.
Published: July 2008

Daily variations in the melatonin concentration in the blood, pineal organ, and retina of the brook trout, Salvelinus fontinalis, were investigated in July under constant photoperiod (16 h L: 8 h D) and temperature (12 °C). Diel variations in melatonin levels in the blood and pineal organ showed similar patterns, with higher values during the night, whereas melatonin concentrations in the retina increased slightly in the first half of the light period. Light exposure of 1 h duration at mid-dark decreased melatonin levels in the blood and pineal organ in an intensity-dependent manner, whereas retinal melatonin levels increased with increasing light intensities. The minimum light intensity causing significant effects on the melatonin concentrations was 2 lx for the serum and 20 lx for the pineal organ and the retina. The parallelism between pineal and circulating melatonin patterns suggests that the lateral eyes of the trout have no significant endocrine function as far as the melatonin rhythm in the blood is concerned. Supporting evidence comes from the reversed response of retinal melatonin to light exposure at mid-dark, and from the low retinal melatonin concentrations found in this study. Thus, the serum melatonin rhythm of the brook trout seems to be mainly the result of rhythmic melatonin secretion from the pineal organ.
Apparent digestive efficiency in walruses (Odobenus rosmarus) fed herring (Clupea harengus) and clams (Spisula sp.)
Authors: Fisher K. I. , Stewart R. E. A. , Kastelein R. A. , Campbell L. D.
Published: July 2008

The digestive efficiency in 4 captive walruses (2 males, 2 females) was determined. All 4 walruses were fed a diet of herring (Clupea harengus), and the adults (1 male, 1 female) were fed clams (Spisula sp.), for a total of 6 animal–diet combinations. The digestive coefficient for energy was the same for both diets ([Formula: see text] SD: 92.7 ± 2.1%; n = 6) but significantly (P = 0.02) higher in females (94.4 ± 1.2%, n = 3) than in males (91.0 ± 0.8%, n = 3). No age effects were found. The mean digestive coefficient of protein was 93.8% ± 1.8% (n = 6) and did not vary among diets or animals. The digestive coefficient for lipid was lower for the clam diet (73.2 ± 0.1%, n = 2) than for the herring diet (94.4 ± 2.3%, n = 4), but this is likely an artifact due to the low lipid content of the clams (5.8 ± 0.7%) and the influence of endogenous lipid loss. The approximate maintenance gross energy requirements for the 1200-kg nonpregnant, nonlactating adult walrus in captivity were 31 350 kcal∙day−1 (1 kcal = 4.18 kJ) or 155 kcal∙kg−0.75∙day−1.
Host, nest, and ecological relationships of species of Protocalliphora (Diptera: Calliphoridae)
Authors: Bennett Gordon F. , Whitworth Terry L.
Published: July 2008

A total of 4781 nests of 110 species of birds was examined for the presence of Protocalliphora in several localities in Ontario, Canada, and the intermountain region of northern Utah. Twenty species belonging to this genus were found in 1621 (33.8%) nests of 73 avian species. Some species, such as P. chrysorrhoea and P. halli, showed strong host preferences, whereas others, such as P. metallica and P. interrupta, preferred specific nest environments. The nests of birds that live in colonies and (or) return to the same site annually were more frequently and heavily infested than those of other birds. In Utah, where 17 species of Protocalliphora occurred, most species showed a degree of host preference, whereas in Ontario, where there were only 9 species, most species preferred specific nest sites. Of the 20 species of Protocalliphora collected during this study, 3 were found exclusively in Ontario and 11 in Utah, with 6 species common to both study areas.
Viruslike particles in cells associated with sensilla in head appendages of a dytiscid beetle
Authors: Zacharuk R. Y. , Leung E. S. , Jensen J. C.
Published: July 2008

Two types of viruslike particles (VLP) were noted in the cytoplasm of cells associated with sensilla on the antennae and labial palps of the diving beetle Graphoderus occidentalis Horn. The most common "hollow" particle was 30–32 nm in diameter with an electron-dense shell about 8 nm thick and, in some cases, a dense core granule about 5.6 nm in diameter. These VLP were always tightly packed in orderly arrays in apparently icosahedral clusters. Such clusters occurred in the perikarya of multiterminal type II neurons and glial cells in the labial nerves, bipolar type I neurons and inner sheath cells of mechano- and chemo-sensilla on both appendages, adjacent epidermal cells, and an axon from an antennal sensillum. A second type of VLP was dense-cored and about 22 nm in diameter. This type was scattered individually or in loose, unordered clusters in a type I sensillar neuron. Both VLP types were closely associated with ribosomes. Some minor cytopathic changes in the contents of cells containing VLP, and the occurrence of VLP as manifestations of physiological stress rather than as infective virions, are discussed.
Electrophoretic comparisons of pheromotypes of the dingy cutworm, Feltia jaculifera (Gn.) (Lepidoptera: Noctuidae)
Authors: Gooding R. H. , Rolseth B. M. , Byers J. R. , Herle C. E.
Published: July 2008

Males of four "sibling species" of Feltia jaculifera, characterized by their mate-recognition system (pheromotype), were examined for electrophoretic variation. Arginine phosphokinase was monomorphic but 14 other enzymes and 1 protein were polymorphic in one or more populations. No locus was diagnostic for any pheromotype. Mean heterozygosity per locus varied from 21 ± 7.8% to 26.7 ± 6.7%, the effective number of alleles per locus varied from 2.19 ± 0.43 to 3.44 ± 0.59, and from 4 to 11 loci were polymorphic in each population. Phenograms indicate that pheromotypes A, B, and D are genetically similar, whilst pheromotype C is distinctly different. Allele frequencies, FST values, and the large percentage (34–43%) of private alleles in sympatric populations of the pheromotypes indicate a genetic substructuring of the nominal species. However, the level of genetic differentiation among pheromotypes A, B, and D is well below that characteristic of sibling species. Nm values suggest that there is sufficient interbreeding between sympatric populations of pheromotypes A and B to preclude genetic differentiation due to drift. The evidence indicates that discrete mate-recognition systems can be achieved without much allozymic differentiation and can be maintained in spite of significant gene flow.
Thermal constraints on swimming performance and escape response of northern water snakes (Nerodia sipedon)
Authors: Weatherhead Patrick J. , Robertson Ian C.
Published: July 2008

We examined the influence of body temperature on swimming speed of northern water snakes (Nerodia sipedon) and determined how variation in water temperature influenced their escape response. In a laboratory experiment, swimming speed increased as a function of water temperature and body size. Swimming speed was less thermally dependent at temperatures approximating the snakes' normal range of activity, suggesting that selection has favoured increased performance breadth at this range. In the field, basking snakes retreated to water when approached. Despite a decrease in swimming speed at lower temperatures, and the cost associated with reduced metabolic rate due to loss of body temperature, however, flight distances were independent of water temperature. We found that basking snakes retreated to water sooner when perched at lower heights, possibly indicating that N. sipedon are more vulnerable to predators when on low perches. Predicting water snake escape behaviour may require not only knowledge of variation both among snakes and in their environment, but also a better understanding of the interaction between the snakes and their natural predators.
Freezing survival of the garter snake Thamnophis sirtalis parietalis
Authors: Churchill Thomas A. , Storey Kenneth B.
Published: July 2008

Cold hardiness was evaluated for the red-sided garter snake, Thamnophis sirtalis parietalis. Snakes collected in the autumn near communal den sites showed an ability to supercool (Supercooling point, SCP = −5.5 °C). However, by midwinter, supercooling capacity was reduced and snakes cooled only to −0.8 to −1.2 °C before freezing. Survival of freezing and body ice contents were determined over a time course of freezing exposure at −2.5 °C. Snakes recovered fully after freezing exposures of 3 h or less that produced ice contents of up to 40% of total body water. After longer periods and with ice contents of over 50%, survival was reduced. Only 50% of snakes survived 10 h of freezing and no snakes recovered after 24 or 48 h with a maximal ice content of 70% of body water. Putative cryoprotectants were assessed in seven organs (liver, kidney, muscle, intestine, brain, lung, heart) as well as the eggs after 5 h of freezing at −2.5 °C. Glucose content increased 4-fold in liver, and lactate rose by 50% in heart, but levels of these and other possible cryoprotectants did not increase in other organs during freezing. However, a high free amino acid pool, including 14–24 μmol/g wet weight taurine, was present in the organs. The data suggest that long-term freezing survival is not part of the winter hibernation strategy of this species, but tolerance of brief freezing exposures may be adaptive in dealing with overnight frosts when the animals are active above ground.
The combined effects of stocking density and sustained exercise on the behaviour, food intake, and growth of juvenile Arctic charr (Salvelinus alpinus L.)
Authors: Christiansen Jørgen Schou , Svendsen Yngvar Stavset , Jobling Malcolm
Published: July 2008

The combined effects of stocking density and sustained exercise on the behaviour and food intake – growth relationship of individually tagged juvenile Arctic charr (Salvelinus alpinus L.) were examined. Both food intake and growth (weight gain) were significantly lower in fish stocked at the high density (initial biomass ~47 kg∙m−3) than in fish stocked at the low density (initial biomass ~23 kg∙m−3). When the charr stocked at low densities were subjected to sustained exercise, they showed higher growth rates than fish reared in standing water (control). In contrast, exercise did not give rise to improved growth performance in fish stocked at high densities. The growth – food intake ratio (food utilization) differed markedly between control and exercised fish. Irrespective of stocking density, food utilization was significantly better in exercising fish than in fish reared in standing water. The differences in food intake, growth, and food utilization are discussed in relation to the changes in behaviour and social interactions induced by forcing the fish to swim against a water current.
Prevalence and intensity of Haemogregarina balli (Apicomplexa: Adeleina: Haemogregarinidae) in three turtle species from Ontario, with observations on intraerythrocytic development
Authors: Siddall Mark E. , Desser Sherwin S.
Published: July 2008

Free-ranging populations of turtles, Chelydra serpentina serpentina, Chrysemys picta marginata, and Clemmys insculpta, were examined for prevalence and intensity of Haemogregarina balli during the summers of 1989 and 1990 in Algonquin Park, Ontario. Prevalence data indicated that C. s. serpentina was the primary intermediate host. The lower prevalence in C. p. marginata and C. insculpta is attributed in part to the relatively smaller surface area available for the attachment and bite of the definitive host, Placobdella ornata. Intensities of bloodstream stages in C. p. marginata and C. insculpta were rarely greater than 1 in 104 erythrocytes. The intensity in C. s. serpentina ranged from 0.5 to 30.0 in 103 erythrocytes. Intensity data for C. s. serpentina demonstrated quantitative and qualitative changes in parasitaemia in 2-week intervals in 1990. It is suggested that the biology of P. ornata is an important influence in these changes. Microscopic and statistical analysis provided independent evidence for binary fission of merozoites in the life history of H. balli.
Stress response of cougars to nonlethal pursuit by hunters
Authors: Harlow Henry J. , Lindzey Frederick G. , Sickle Walter D. Van , Gern William A.
Published: July 2008

Five cougars (Felis concolor) were captured and an adrenal response test was administered by injecting synthetic adrenocorticotropic hormone and monitoring plasma cortisol levels at 15-min intervals for 120 min. Three were selected for treatment and chased 5 or 6 more times to simulate the stress they might experience during a pursuit-only season; the other two served as controls and were chased only once more, at recapture. The adrenal response test was administered again at recapture. The cougars in the treatment group had a lowered plasma cortisol profile after the simulated pursuit season, indicating an altered physiological response of the adrenals to the stress of repeated chases.
The relationship between stream or river discharge and thyroid hormone levels in wild adult Atlantic salmon (Salmo salar L.)
Authors: Youngson Alan F. , Webb John H.
Published: July 2008

Thyroxine and tri-iodothyronine levels were determined in groups of adult Atlantic salmon (Salmo salar L.) of both sexes at river entry in summer or as they entered a spawning tributary in late autumn. Hormone levels were considered in relation to river or stream discharge rate at capture. For tri-iodothyronine, there was a quadratic or linear relationship with discharge rate for each sex at both sites. For thyroxine, there was a quadratic relationship with discharge rate at tributary entry but no relationship with discharge rate at river entry. It is argued that raised hormone levels at higher discharge rates are a probable consequence of increased motor activity associated with greater water velocity. The quadratic nature of most of the models is attributed to physiological or behavioural limitation of the response.
Mouvements des mâchoires pharyngiennes pendant la prise de nourriture chez le Serranus scriba (Linné, 1758) (Pisces, Serranidae)
Authors: Vandewalle P. , Havard M. , Claes G. , Vree F. De
Published: July 2008

According to the morphology of its pharyngeal jaw apparatus, Serranus scriba can be considered as an intermediate type within the Acanthopterygians. The lower jaws are united only at their fore end. The upper pharyngeal jaws do not articulate with the skull base. Each of them consists of pharyngobranchials 2 and 3 (the latter being well developed), bearing a tooth plate, and of one posterior tooth plate, associated with two smaller tooth plates supported by epibranchials 2 and 3. The branchial musculature is of a generalized perciform type. Muscle activity generates variable cyclic movements of the pharyngeal jaws for transporting prey from the buccal cavity to the oesophagus, in cases where the prey is provided with a shell or a cuticle. Masticatory movements are not stereotyped as in more specialized fishes such as Labridae. Prey transport is more efficient when the upper and lower pharyngeal jaws retract together, either in complete synchrony or with a phase shift. This is often accompanied by downward movements of the upper jaws. The amplitude of movements of the components of the upper pharyngeal jaw may vary within one cycle. For instance, pharyngobranchial 2 could be drawn more forward, while pharyngobranchial 3 could be drawn more backward and the posterior tooth plate could move up and down independently. These movements can be induced passively by the interactions with the prey and (or) eventually by specific muscular activity as well. Stereotyped movements of other species probably allow them to meet only the requirements of a specialized diet. In contrast, the flexibility of this movement pattern allows S. scriba to explore a wider range of food types.
Host specificity in the slave-making ant Harpagoxenus canadensis M. R. Smith
Authors: Heinze Jürgen , Stuart Robin J. , Alloway Thomas M. , Buschinger Alfred
Published: July 2008

The slave-making ant Harpagoxenus canadensis frequently parasitizes two host species in the genus Leptothorax (subgenus Leptothorax s.str.) which are part of the L. "muscorum" complex and are currently referred to as Leptothorax sp. A and Leptothorax sp. B. A sympatric member of this subgenus, L. retractus, is rarely enslaved. Of 48 complete slave-maker colonies from various sites, 26 contained only Leptothorax sp. A slaves (54.2%), 11 contained only Leptothorax sp. B slaves (22.9%), and 11 contained slaves of both species (22.9%). Of 65 partial slave-maker colonies from one site, 10 contained only Leptothorax sp. A slaves (15.4%), 55 contained only Leptothorax sp. B slaves (84.6%), and none contained slaves of both species. Leptothorax retractus was common at some sites but was never found as a slave in this study. Differences in host-utilization patterns within and between populations might reflect differing host densities but could be influenced by genetic or learned predispositions of the parasites or differential interspecific compatibilities among the various species. Possible collector bias must also be considered. Female reproductives of the host species (n = 13) were occasionally found in slave-maker nests. Most of these were Leptothorax sp. A intermorphs (workerlike females; n = 11) and were inseminated but not egg laying. The only Leptothorax sp. A gynomorph (a primarily winged female) was uninseminated and not egg laying, and the only Leptothorax sp. B gynomorph could not be dissected.
Effect of density and individual variation on growth of sea lamprey (Petromyzon marinus) larvae in the laboratory
Authors: Murdoch Scott P. , Docker Margaret F. , Beamish F. William H.
Published: July 2008

Sea lamprey (Petromyzon marinus) larvae were individually marked with subcutaneous injections of latex dye and maintained in the laboratory from June 1988 to February 1989 at tank densities of 10, 50, and 100 larvae per 0.3 m2 of substrate. Growth, measured as change in total length and weight, varied widely among individuals: change in length during a 3-month period differed by as much as 17.0 mm within one tank of 10 larvae. Despite individual variation, growth decreased significantly with increasing density: the mean increase in length (± standard error) over the 8-month period was 17.3 ± 3.0, 4.3 ± 1.5, and −1.4 ± 1.0 mm at low, medium, and high density, respectively. The initial length or the sex of an individual at the end of the experiment had little or no effect on growth. Mortality was negligible (1.6%), and could not be significantly correlated with density, size, or sex. The overall sex ratio was 33% male, and did not vary significantly with tank or density.
Ornithodoros peringueyi (Argasidae) and Xenopsylla trispinis (Siphonaptera), probable intermediate hosts of Hepatozoon atticorae of the South African Cliff Swallow, Hirundo spilodera
Authors: Bennett Gordon F. , Earlé Roy A. , Penzhorn Banie L.
Published: July 2008

Developing and mature oocysts of Hepatozoon atticorae of the Hirundinidae were detected in the haemolymph of 60% f the Ornithodoros peringueyi (Argasidae) and 25% of the Xenopsylla trispinis (Pulicidae) that occurred in a colony of South African Cliff Swallows (Hirundo spilodera). Fifty-seven percent of the adult birds harboured the hepatozoan, but none of the eight immature swallows examined were infected. It is speculated that the adult birds become infected by ingesting infected arthropods while preening.
Spawning activity of male and female pike, Esox lucius L., determined by acoustic tracking
Authors: Lucas M. C.
Published: July 2008

Two male and three female pike, Esox lucius L., were tracked by means of intraperitoneally implanted acoustic transmitters prior to and throughout the 1988 spawning season in Loch Davan, Scotland. Highly significant variations in activity occurred on a diel and seasonal basis. Fish were relatively inactive at night for the whole of the tracking period. Mean daily distance moved ranged between 0.43 and 0.44 km∙d−1 for females and between 0.24 and 0.38 km∙d−1 for males in the weeks preceding spawning (March 27 – April 16); increased to a peak of 1.13 km∙d−1 for females and 1.72 km∙d−1 for males in the week April 24–30; and subsequently decreased to prespawning levels, 0.29 km∙d−1 for females and 0.24 km∙d−1 for males, by the week May 8–14. Levels of visually observed pike spawning activity followed a similar pattern. Males were more active than females for most of the spawning period; no significant differences were found before and after spawning. Highest levels of activity coincided with elevated water levels and water temperatures of 8–10 °C.
Parr–smolt transformation of a nonanadromous population of Atlantic salmon (Salmo salar) in Norway
Authors: Staurnes Magne , Lysfjord Grete , Berg Ole Kristian
Published: July 2008

Morphological and physiological indices of parr–smolt transformation of fish from anadromous and nonanadromous hatchery-reared populations of Atlantic salmon (Salmo salar) were compared. Both anadromous and nonanadromous Atlantic salmon showed a complete smolt colouration and had a similar high gill Na+,K+–ATPase activity (significantly (P < 0.05) different from that of parr), indicating both morphological and physiological aspects of parr–smolt transformation. The evolutionary stability of the parr–smolt transformation of nonanadromous Atlantic salmon is discussed.
Growth and early sexual maturation in Baltic salmon (Salmo salar) parr
Authors: Berglund Ingemar
Published: July 2008

The relationship between sexual maturation and growth in Baltic salmon (Salmo salar) parr was studied in hatchery stock originating from the Umeälven (Ume River) in northern Sweden. The probability that a male parr would mature sexually at age 1 + was positively related to its size at the start of the experiment at age 0+. The specific growth rate and condition factor of maturing and nonmaturing males were similar until the onset of gonadal growth, when the growth rate of maturing males decreased. Sibling groups of immature parr were fed different rations during the 3 weeks prior to the start of gonadal development. The incidence of sexual maturation in the groups given different rations was linearly related to the growth rate during the period of different feeding rates. This study suggests that both the size at age 1, resulting from the growth rate during the first summer, and the opportunity for growth during the period preceding the onset of gonadal growth affect the incidence of maturation in male parr of age 1 +.
Nematodirinae (Nematoda : Trichostrongyloidea) chez l'Oreamnos americanus en Alberta, Canada, description du Nematodirus becklundi sp. nov.
Authors: Durette-Desset M.-C. , Samuel W. M.
Published: July 2008

Two Nematodirus parasites from Oreamnos americanus from Alberta, Canada, were studied, namely Nematodirus maculosus and Nematodirus becklundi n.sp. Nematodirus becklundi is characterized by the length of the cephalic vesicle being less than double the width, the number of denticles on the corona radiata less than 40, the absence of narrow lateral longitudinal ridges in the anterior part of the body, the absence of a notch between the dorsal and lateral bursal lobes, and the spicules' fused parts (shafts excluded) being shorter than their shafts. Opposite features characterize N. maculosus with which it was probably confounded. In contrast with recent data from the literature, the synlophe of N. maculosus is characterized by a variable number of ridges at the level of the deirids, but always greater than 16.
Metabolic rate and body composition of harbour seals, Phoca vitulina, during starvation and refeeding
Authors: Markussen Nina Hedlund , Ryg Morten , Øritsland Nils Are
Published: July 2008

The metabolic rate of normally fed harbour seals (Phoca vitulina) was measured during starvation and the subsequent refeeding period. Resting metabolic rate was calculated from the y-intercept of the metabolic rate versus swimming speed curves and was 20% lower during the starvation period than during normal feeding. During starvation, about 50% of mass loss was fat, i.e., 77% of the energy was obtained from fat. Metabolic rate returned to the initial value about 1 week after the onset of refeeding.