Spatial ecology of non-native common carp (Cyprinus carpio) in Lake Ontario with implications for management.

Common carp, Cyprinus carpio, are a non-native species that established within the Laurentian Great Lakes more than a century ago and are abundant in some locations. Common carp have negatively impacted freshwater ecosystems, including in the Great Lakes, by increasing turbidity and uprooting vegetation through foraging and/or spawning activities. Knowledge of spatial ecology is necessary to effectively manage non-native species and aid in the development of remediation strategies. The aim of this study was to examine the spatial ecology of common carp across multiple spatial scales within Lake Ontario using passive acoustic telemetry. First, Residency Index (RI), as a metric for habitat preference, was calculated for common carp in Toronto Harbour (TH) and Hamilton Harbour (HH). Linear mixed modelling revealed that season, as well as the interaction between season and physical habitat conditions significantly affected RI. Specifically, during spring and summer common carp had significantly higher RI at sites with increased submerged aquatic vegetation, which could be associated with spawning activities. All common carp tagged in HH were resident, compared to half of individuals tagged in TH. Larger individuals tagged in TH were more likely to be absent from the array during summer. Non-resident common carp tagged at TH made extensive movements in spring and summer along the nearshore of Lake Ontario and were detected throughout the entire basin. Knowledge of spawning habitat could inform efforts to exclude common carp from these specific locations. Based on our findings, common carp should be managed at a regional level, as opposed to single sites, owing to their extensive movements. Supplementary Information: The online version contains supplementary material available at 10.1007/s00027-022-00917-9.

Use of Fish Telemetry in Rehabilitation Planning, Management, and Monitoring in Areas of Concern in the Laurentian Great Lakes.

Freshwater ecosystems provide many ecosystem services; however, they are often degraded as a result of human activity. To address ecosystem degradation in the Laurentian Great Lakes, Canada and the United States of America established the Great Lakes Water Quality Agreement (GLWQA). In 1987, 43 highly polluted and impacted areas were identified under the GLWQA as having one or more of 14 Beneficial Use Impairments (BUIs) to the physical and chemical habitat for fish, wildlife and humans, and were designated as Areas of Concern (AOC). Subnational jurisdictions combined with local stakeholders, with support from federal governments, developed plans to remediate and restore these sites. Biotelemetry (the tracking of animals using electronic tags) provides information on the spatial ecology of fish in the wild relevant to habitat management and stock assessment. Here, seven case studies are presented where biotelemetry data were directly incorporated within the AOC Remedial Action Plan (RAP) process. Specific applications include determining seasonal fish-habitat associations to inform habitat restoration plans, identifying the distribution of pollutant-indicator species to identify exposure risk to contamination sources, informing the development of fish passage facilities to enable fish to access fragmented upstream habitats, and assessing fish use of created or restored habitats. With growing capacity for fish biotelemetry research in the Great Lakes, we discuss the strengths and weaknesses of incorporating biotelemetry into AOC RAP processes to improve the science and practice of restoration and to facilitate the delisting of AOCs.

Using genetic inference to re-evaluate the minimum longevity of the lemon shark Negaprion brevirostris.

A combination of mark-recapture and genetic sampling was used to extend the minimum longevity of an elasmobranch species and the life span estimate of the lemon shark Negaprion brevirostris was increased conservatively from 20·2 to 37 years. This increase in longevity means higher vulnerability and a longer recovery time from exploitation.

Development of an injectable two-phase drug delivery system for sequential release of antiresorptive and osteogenic drugs.

Unlike controlled release systems that deliver a single drug, dual or multidrug delivery systems with distinct release profiles are more likely to promote timely and effective tissue regeneration as they provide both temporally and concentration-dependent release of different molecules to mimic natural biological events. In this study, an injectable and biodegradable delivery system was developed to sequentially release an antiresorptive drug (clodronate) followed by an osteogenic agent (simvastatin) to treat bone disease. The injectable delivery system comprised simvastatin-loaded gelatin microspheres suspended in a viscous solution of carboxymethylcellulose (CMC) containing clodronate. Several factors (CMC concentration, glutaraldehyde concentration, simvastatin loading, and gelatin microsphere processing conditions) were investigated for their effects on drug release. Clodronate release was not affected by CMC concentration, with complete delivery within 12 hr, and simvastatin release could be modulated by cross-linking of the gelatin microspheres, loading, and washing conditions. Burst release of simvastatin was reduced from 70% to 6% in conjunction with sustained release for up to 3 weeks. The combined system showed early release of the antiresorptive clodronate sequentially followed by sustained delivery of the osteogenic simvastatin. This robust and flexible two-phase delivery system may prove useful for applications in which multiple drug delivery is desired.

Psychogenic non-epileptic seizures--definition, etiology, treatment and prognostic issues: a critical review.

In this review we systematically assess our currently available knowledge about psychogenic non-epileptic seizures (PNES) with an emphasis on the psychological mechanisms that underlie PNES, possibilities for psychological treatment as well as prognosis. Relevant studies were identified by searching the electronic databases. Case reports were not considered. 93 papers were identified; 65 of which were studies. An open non-randomized design, comparing patients with PNES to patients with epilepsy is the dominant design. A working definition for PNES is proposed. With respect to psychological etiology, a heterogeneous set of factors have been identified. Not all factors have a similar impact, though. On the basis of this review we propose a model with several factors that may interact in both the development and prolongation of PNES. These factors involve psychological etiology, vulnerability, shaping, as well as triggering and prolongation factors. A necessary first step of intervention in patients with PNES seems to be explaining the diagnosis with care. Although the evidence for the efficacy of additional treatment strategies is limited, variants of cognitive (behavioural) therapy showed to be the preferred type of treatment for most patients. The exact choice of treatment should be based on individual differences in the underlying factors. Outcome can be measured in terms of seizure occurrence (frequency, severity), but other measures might be of greater importance for the patient. Prognosis is unclear but studies consistently report that 1/3rd to 1/4th of the patients become chronic.

Psychogenic non-epileptic seizures--diagnostic issues: a critical review.

In this review we systematically assess our current knowledge about psychogenic non-epileptic seizures (PNES), epidemiology, etiology, with an emphasis on the diagnostic issues. Relevant studies were identified by searching the electronic databases. Case reports were not considered. Articles were included when published after 1980 up till 2005 (26 years). A total of 84 papers were identified; 60 of which were actual studies. Most studies have serious methodological limitations. An open non-randomized design, comparing patients with PNES to patients with epilepsy is the dominant design. The incidence of PNES in the general population is low. However, a relatively high prevalence is seen in patients referred to epilepsy centres (15-30%). Caution is needed in the clinical interpretation of ictal features suggested to be pathognomic for PNES. Video-EEG is widely considered to be the gold standard for diagnosing PNES. Still the differential diagnosis epileptic/non-epileptic seizures can be difficult. Despite the current available technical facilities, the mean latency between onset of PNES and final diagnosis as being non-epileptic and psychogenic is approximately 7 years. One of the reasons for diagnostic delay is that the diagnosis of PNES is often limited to a 'negative' process and consequently PNES is characterized as a 'non-disease' (i.e. 'not epilepsy'). The psychological diagnosis is thus an important, although not a conclusive, 'second phase' aspect of medical decision making. Specific relations between seizure presentation and underlying psychological mechanisms are not conclusive. A classification between major motor manifestations and unresponsiveness is recognized. With respect to psychological etiology, a heterogeneous set of factors have been identified that may be involved in the causation, development and provocation of PNES.

Treatments for non-epileptic attack disorder.

BACKGROUND: Psychogenic non-epileptic seizures (NES) have the outward appearance of epilepsy in the absence of physiological or electroencephalographic correlates. Non-epileptic seizures can occur in isolation or in combination with epileptic seizures. The development and maintenance of non-epileptic seizures has been well documented and there is a growing literature on the treatment of NES which includes non-psychological (including anti-anxiety and antidepressant pharmacological treatment) and psychological therapies (including cognitive behavioural therapy (CBT), hypnotherapy and paradoxical therapy). Various treatment methodologies have been tried with variable success. The purpose of this Cochrane review was to establish the evidence base for the treatment of NES. OBJECTIVES: To assess whether treatments for NES result in a reduction in frequency of seizures and/or improvement in quality of life, and whether any treatment is significantly more effective than others. SEARCH STRATEGY: We searched the Cochrane Epilepsy Group's Specialised Register (September 2005), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2005), MEDLINE (1966 to July 2005), and PsycINFO (1806 to July 2005). No language restrictions were imposed. We checked the reference lists of retrieved studies for additional reports of relevant studies SELECTION CRITERIA: Randomised or quasi-randomised studies were included that assessed one or more types of psychological or non-psychological interventions for the treatment of NES. Studies of childhood NES were excluded from our review. DATA COLLECTION AND ANALYSIS: Three review authors independently assessed the trials for inclusion and extracted data. Outcomes included reduction in seizure frequency and improvements in quality of life. MAIN RESULTS: Three small studies met our inclusion criteria and were of poor methodological quality. Two assessed hypnosis and the other paradoxical therapy. There were no detailed reports of improved seizure frequency or quality of life outcomes, and these trials provide no reliable evidence of a beneficial effect of these interventions. AUTHORS' CONCLUSIONS: In view of the methodological limitations and the small number of studies, we have no reliable evidence to support the use of any treatment including hypnosis or paradoxical injunction therapy in the treatment of NES. Randomised studies of these and other interventions are needed.

Dynamics of carriage of Neisseria meningitidis in a group of military recruits: subtype stability and specificity of the immune response following colonization.

Meningococcal carriage and the immune response to colonization were studied in a group of military recruits undergoing basic training. Subtyping by determination of the class 1 protein sequence clearly differentiated between strains and demonstrated the dynamics of carriage and transmission. Expression of class 1 protein by each strain remained stable during prolonged carriage by different subjects. Following colonization, a marked increase in serum bactericidal response occurred, which was specific for the subtype of the acquired strain and was associated with an increase in reactivity by Western blot to the homologous class 1 protein. Subjects colonized by multiple strains showed evidence of a specific immune response to the class 1 protein of each strain acquired. The subtype specificity of the bactericidal response to meningococci and the stability of expression of the class 1 protein have important implications for the design of vaccines for prevention of serogroup B meningococcal disease.

Dietary triggers in irritable bowel syndrome.

Irritable bowel syndrome (IBS) is a frequently occurring, benign functional gastrointestinal disorder with a complex poorly understood pathology which appears to be multifactorial in nature. There is no association with structural or biochemical abnormalities in the gastrointestinal tract. Functional variations in myoelectrical activity, visceral hypersensitivity and illness behaviours have all been observed in patients experimentally. In conjunction with environmental, psychological and alimentary factors, these mechanisms have been proposed as the major determinants of symptom genesis. Certainly, dietary factors are frequently perceived by sufferers as powerful symptom triggers, with many reporting multiple food intolerance. Physicians, however, remain divided upon the relevance of food to the disorder, with many eschewing a nutritional connection. This is unsurprising as, despite much experimental work to determine the clinical relevance of food intolerance and allergy to the aetiology of the disorder, the vast range of foodstuffs available for testing, inherent procedural problems with test foods, methodological insufficiencies and the continually evolving knowledge of the disorder, particularly the subgrouping of sufferers, have restricted the scientific validity of current findings. At the present time, it is difficult to make informed judgement upon the importance of food in IBS, and rigorously designed, large scale trials devised in the light of recent knowledge are required before conclusions can be drawn.

Light-induced spectral changes in fully oxidized cytochrome c oxidase in the presence of oxygen.

Illumination of oxidized cytochrome oxidase with low intensity (<2 mW) light below 300 nm in the presence of oxygen causes pH-dependent spectral changes in the Soret and visible regions. The light-induced difference spectra show a peak at 438 nm and a trough at 414 nm in the Soret region and a peak at 606 nm and a shoulder at approximately 577 nm in the visible region. The effect was inhibited by cyanide, suggesting the involvement of cytochrome a3. The pH dependence indicates two titratable groups with pKa values of 6.52 +/- 0.26 and 6.85 +/- 0.15. The spectral changes are analogous to those occurring upon addition of hydrogen peroxide to the fully oxidized enzyme, which results in a mixture of species with absorbance maxima at 607 and 580 nm when referenced against the oxidized enzyme. Catalase addition affected the initial onset of the spectral change and increased the rate at which the reverse reaction occurred upon termination of illumination. The data are consistent with a mechanism involving light-induced autoreduction of the binuclear center and subsequent O2 binding, followed by the release of hydrogen peroxide and the formation of a mixture of the 607 nm and 580 nm forms.

Sequence variation in class 1 outer membrane protein in Neisseria meningitidis isolated from patients with meningococcal infection and close household contacts.

The meningococcal porA gene encodes the class 1 outer membrane protein which contains the VR1 and VR2 regions responsible for sero-subtype specificity. However, sequence variations may occur within these regions which are not recognised by the currently available subtype antibodies. Since this "silent" microheterogeneity represents a potential hidden source of information, in the current study we have used porA gene sequence analysis to study strains isolated from cases of meningococcal infection and close household contacts. With each of the three subtypes studied, the index cases could be differentiated from each other by sequence variations within at least one of the VR1, VR2 and SV1 regions. In addition, although isolates from close household contacts showed a high degree of homology significant differences could be detected within some family groups. These data demonstrate that it is possible to use sequence information to differentiate between potential sources of infection which appear identical using conventional serological methods.

Comparison of the class-1 outer membrane protein from B:15:P1.16 Neisseria meningitidis strains isolated from patients previously immunized with a serogroup B outer membrane protein vaccine in Norway.

A previous report of a large, double blind, efficacy trial of an experimental Group B meningococcal outer membrane protein vaccine carried out in Norwegian Teenagers, showed a protection rate of 57%. Previous studies had demonstrated the occurrence of mutations in the class-1 outer membrane protein which alter its immunological properties. The occurrence of new mutations might compromise the efficacy of a vaccine and explain the occurrence of any vaccine failures. The porA gene, which encodes expression of the class 1 protein, was sequenced in all isolates from vaccine failures and compared to that of the vaccinating strain H44/76 (B:15:P1.7,16). The porA DNA and deduced amino acid sequences were all identical to that of the vaccinating strain except for that of one isolate which had a sequence identical to strains previously reported in Norway and England with a 'masked P1.7' epitope. The absence of new mutations in the trial was encouraging for the further development of outer membrane protein vaccines.

Experimental enzyme-linked amperometric immunosensors for the detection of salmonellas in foods.

Two enzyme-linked amperometric immunosensors specific for salmonellas were developed as rapid methods for quantifying and detecting these organisms in pure cultures and foods. Both used alkaline phosphatase as the enzyme reporter molecule but one system used phenyl phosphate as the substrate followed by the electrochemical detection of phenol at a polarized platinum electrode. The other system incorporated an enzyme amplification step and relied on the electrochemical detection of a reduced mediator, ferrocyanide. Both assays were rapid (4 h) and specific and generated salmonella-dependent signals above 10(4) cfu/ml (phenyl phosphate system) or 10(5) cfu/ml (enzyme amplified system) in pure cultures and samples of several foods, although the results with beef samples showed considerable variation. Both systems were able to detect low (1-5 cfu/g or /ml) numbers of salmonellas in foods after non-selective (18 h) and selective (22 h) enrichment steps but four samples, out of 147, gave false positive results. False positive results were eliminated by reducing the enrichment steps to 6 h and 18 h respectively (90 samples).

Direct application to dairy foods of a Listeria-specific oligonucleotide probe to 16S rRNA.

A potentially Listeria-specific 28 base oligonucleotide probe was designed from 16S rRNA sequence data. Using either 32P or non-radioactive (alkaline phosphatase) labels, the probe was shown to be highly specific as it hybridised to RNA extracted from all of the species of Listeria but not to any of the other bacteria tested. Both probe methods were highly sensitive and ca 10(2) cfu/ml Listeria could be detected in pure cultures. A rapid procedure for extracting RNA from milk, Camembert and cottage cheese was developed. This allowed the direct application of the probe to these foods and gave a rapid and specific method of detecting > 10(2) cfu/g or ml Listeria in these foods.

Use of the polymerase chain reaction and oligonucleotide probes for the rapid detection and identification of Carnobacterium species from meat.

The polymerase chain reaction (PCR) was used selectively to amplify specific rDNA sequences of Carnobacterium divergens, C. mobile, C. piscicola and C. gallinarum in purified DNA extracts, crude cell lysates and food samples. The PCR products were visualized by agarose gel electrophoresis and identified, at species level, by hybridization reactions with three specific oligonucleotide probes for C. divergens, C. mobile and C. piscicola/C. gallinarum designed from 16S rRNA sequence data. The PCR was sufficiently sensitive to amplify DNA from a single bacterium to detectable levels after 30 cycles of amplification. Both radioactive (32P) and non-radioactive alkaline phosphatase labelled probes was able to detect the PCR products. Detection was highly specific and the probes did not hybridize with DNA samples from any other of the bacterial species tested. These methods enabled the rapid and specific detection and identification of carnobacteria from pure cultures and samples of meat.

The T cell receptor V alpha 11 gene family. Analysis of allelic sequence polymorphism and demonstration of J alpha region-dependent recognition by allele-specific antibodies.

Allelic polymorphism in TCR loci may play an important role in shaping the T cell repertoire and in disease susceptibility. We have used a combination of antibody and sequence analysis to investigate polymorphism in the murine V alpha 11 family. Two different antibodies have been analyzed that recognize particular V alpha 11 family members of the V alpha b and V alpha d haplotypes. One antibody shows J alpha dependency, suggesting a conformational element to the epitope. Investigation of the anti-V alpha 11 staining pattern on different mouse strains indicates that there is a marked influence of MHC haplotype on V alpha 11 selection and that V alpha 11 is preferentially expressed on CD4+ cells. Sequence analysis of V alpha 11 genes from the V alpha a, V alpha b, and V alpha d haplotypes shows two potential regions for the haplotype-specific epitopes. The relatedness of the different V alpha 11 family members from different haplotypes suggests that the V alpha 11.1/11.2 gene duplication is relatively recent, but that V alpha 11.3 separated much earlier. Differences between V alpha 11.3 and V alpha 11.1/11.2 are concentrated in the putative complementarity determining regions (CDR), whereas differences between alleles are not clearly clustered. However, the V alpha 11.1a and V alpha 11.1d alleles differ from V alpha 11.1b and V alpha 11.2b in CDR1. A V alpha 11.2-expressing anti-cytochrome c T cell has the same V-J junction as a V alpha 11.1-bearing cell with a similar fine specificity, indicating that V alpha 11.1b and V alpha 11.2b do not contribute different Ag specificities.

Increased sensitivity of an enzyme-amplified colorimetric immunoassay for protein A-bearing Staphylococcus aureus in foods.

A modification to the enzyme amplification system described by Self (1984), has been developed in which the addition of semicarbazide hydrochloride increased the sensitivity of detection of protein A-bearing Staphylococcus aureus in foods from 4-6 X 10(3) to 20 colony forming units (c.f.u.) g-1 or ml-1. This may be due to the removal of acetaldehyde produced as a by-product of the amplification cycle thereby permitting further cycling to proceed.

Sensitive enzyme-amplified electrical immunoassay for protein A-bearing Staphylococcus aureus in foods.

An amperometric electrochemical immunoassay specific for protein A-bearing Staphylococcus aureus was developed. The method was based on a sandwich immunosorbent assay and incorporated an enzyme amplification step, using a NAD-specific redox cycle generating NADH (C. H. Stanley, A. Johannsson, and C. H. Self, J. Immunol. Methods 83:89-95, 1985). Reduction of the mediator, ferricyanide, was dependent on the initial concentration of antigen. The final potential was measured by using a Pt disk electrode polarized at +0.8 V to the Ag/AgCl reference electrode. The assay was rapid (4 h) and generated protein A- and cell (S. aureus)-dependent signals. The system was highly sensitive and could detect 10 pg of protein A ml-1 and less than 100 CFU of S. aureus ml-1. Similar sensitivities were observed with S. aureus cultures inoculated into beef and milk, but the sensitivity was reduced slightly (ca. 10(3) g-1) with samples of Cheddar cheese.

A semi-homogeneous amperometric immunosensor for protein A-bearing Staphylococcus aureus in foods.

A semi-homogeneous amperometric immunosensor specific to the protein A of Staphylococcus aureus was developed using direct electrochemical detection of phenol produced by alkaline phosphatase from phenyl phosphate. The immunosensor could reliably detect strains of protein A-bearing S. aureus in pure cultures at ca. 10(4) cfu/ml, and at ca. 10(5) cfu/g or ml in various food samples. Due to its semi-homogeneous nature, the system was very simple, easy to operate, and labour-saving. The good correlation between the amperometric current generated by the immunosensor and plate counts illustrated the potential usefulness of this simple system. It proved to be a reliable 24-h detection method for food samples containing very low numbers of protein A-bearing S. aureus after pre-enrichment, as it was able to detect cells that could not directly be enumerated by plate counts.

An improved amperometric immunosensor for the detection and enumeration of protein A-bearing Staphylococcus aureus.

An amperometric immunosensor specific to the protein A of Staphylococcus aureus, was developed using the direct electrochemical detection of phenol produced by alkaline phosphatase from phenylphosphate. The immunosensor could detect protein A at 0.01 ng/ml and could reliably detect and quantify pure cultures of protein A-bearing Staph. aureus above 10(3) cfu/ml. A similar sensitivity of detection was obtained with samples of beef and milk.