Spatial ecology of coastal Atlantic cod Gadus morhua associated with parasite load.

Acoustic tags and receivers were used to investigate the spatial ecology of coastal Atlantic cod Gadus morhua (n = 32, mean fork length: 50 cm, range: 33-80 cm) on the Norwegian Skagerrak coast in 2012. Monthly home ranges (HR), swimming activity and depth use varied considerably among individuals and through the months of June, July and August. HR sizes for the period ranged from 0.25 to 5.20 km2 (mean = 2.30 km2. Two thirds of the tagged G. morhua were infected with black spot disease Cryptocotyle lingua parasites; these fish had larger HRs and occupied deeper water compared with non-infected fish. The infected fish also tended to be more active in terms of horizontal swimming. From an ecological and evolutionary perspective, any environmental change that modifies G. morhua behaviour may therefore also alter the parasite load of the population, and its conservation and fishery status.

Are low but statistically significant levels of genetic differentiation in marine fishes 'biologically meaningful'? A case study of coastal Atlantic cod.

A key question in many genetic studies on marine organisms is how to interpret a low but statistically significant level of genetic differentiation. Do such observations reflect a real phenomenon, or are they caused by confounding factors such as unrepresentative sampling or selective forces acting on the marker loci? Further, are low levels of differentiation biologically trivial, or can they represent a meaningful and perhaps important finding? We explored these issues in an empirical study on coastal Atlantic cod, combining temporally replicated genetic samples over a 10-year period with an extensive capture-mark-recapture study of individual mobility and population size. The genetic analyses revealed a pattern of differentiation between the inner part of the fjord and the open skerries area at the fjord entrance. Overall, genetic differentiation was weak (average F(ST) = 0.0037), but nevertheless highly statistical significant and did not depend on particular loci that could be subject to selection. This spatial component dominated over temporal change, and temporal replicates clustered together throughout the 10-year period. Consistent with genetic results, the majority of the recaptured fish were found close to the point of release, with <1% of recaptured individuals dispersing between the inner fjord and outer skerries. We conclude that low levels of genetic differentiation in this marine fish can indeed be biologically meaningful, corresponding to separate, temporally persistent, local populations. We estimated the genetically effective sizes (N(e) ) of the two coastal cod populations to 198 and 542 and found a N(e) /N (spawner) ratio of 0.14.

Quantitative genetic parameters for wild stream-living brown trout: heritability and parental effects.

Adaptability depends on the presence of additive genetic variance for important traits. Yet few estimates of additive genetic variance and heritability are available for wild populations, particularly so for fishes. Here, we estimate heritability of length-at-age for wild-living brown trout (Salmo trutta), based on long-term mark-recapture data and pedigree reconstruction based on large-scale genotyping at 15 microsatellite loci. We also tested for the presence of maternal and paternal effects using a Bayesian version of the Animal model. Heritability varied between 0.16 and 0.31, with reasonable narrow confidence bands, and the total phenotypic variance increased with age. When introducing dam as an additional random effect (accounting for c. 7% of total phenotypic variance), the level of additive genetic variance and heritability decreased (0.12-0.21). Parental size (both for sires and for dams) positively influenced length-at-age for juvenile trout--either through direct parental effects or through genotype-environment correlations. Length-at-age is a complex trait reflecting the effects of a number of physiological, behavioural and ecological processes. Our data show that fitness-related traits such as length-at-age can retain high levels of additive genetic variance even when total phenotypic variance is high.

New Danish reference values for height, weight and body mass index of children aged 0-5 years.

AIM: To derive new reference values for height, weight and body mass index (BMI) of children aged 0-5 years in Denmark and to compare them with the national reference from the 1970s and the 2006 WHO standard. METHODS: The height and weight of 4105 healthy singleton children born in 1995 were obtained from a cohort study. Children were measured at birth and at seven regular health examinations by a general practitioner up to 5 years of age. Generalized additive models for location, scale and shape were used to construct percentile curves. RESULTS: Mean length, weight and BMI at birth and during the first months of life increased significantly, but the differences diminished thereafter, and at 1 year BMI had decreased. In boys, weight and BMI had decreased by 2 years of age but had increased, together with height, at 5 years. Children were taller, heavier and had a higher BMI than that referred to in the WHO standard. CONCLUSION: New references for length or height, weight and BMI by age were constructed for children in Denmark. Since the 1970s, weight, length and BMI at birth increased, and growth during the first year of life appears to be healthier.

Sibling-size variation in brown trout Salmo trutta in relation to egg size and stream size.

Sibling-size variation (SSV), estimated as the coefficient of variation of egg size, was investigated for 13 populations of brown trout Salmo trutta. SSV was negatively correlated with mean egg size both at the population and individual levels. After correction for the effect of mean egg size, SSV was also negatively correlated with stream size. These results provide new information about how salmonid SSV can vary at different ecological scales (individual, population and region). The results are discussed in light of competing theories for explaining SSV: (1) the passive effect hypothesis, stating that egg size variation follows passively from selection on egg size and (2) the bet-hedging hypothesis, stating that high SSV is adaptive in unpredictable environments.

Predictors (0-10 months) of psychopathology at age 11/2 years - a general population study in The Copenhagen Child Cohort CCC 2000.

BACKGROUND: Epidemiological studies of mental health problems in the first years of life are few. This study aims to investigate infancy predictors of psychopathology in the second year of life. METHODS: A random general population sample of 210 children from the Copenhagen Child Birth Cohort CCC 2000 was investigated by data from National Danish registers and data collected prospectively from birth in a general child health surveillance programme. Mental health outcome at 1(1/2) years was assessed by clinical and standardised measures including the Child Behavior Check List 1(1/2)-5 (CBCL 1(1/2)-5), Infant Toddler Symptom Check List (ITSCL), Checklist for Autism in Toddlers (CHAT), Bayley Scales of Infant Development (BSID II), Mannheim Eltern Interview (MEI), Parent Child Early Relational Assessment (PC ERA) and Parent Infant Relationship Global Assessment Scale (PIR-GAS), and disordered children were diagnosed according to the International Classification of Diseases (ICD-10) and Diagnostic Classification Zero to Three (DC: 0-3). RESULTS: Deviant language development in the first 10 months of life predicted the child having any disorder at 1(1/2) years, OR 3.3 (1.4-8.0). Neuro-developmental disorders were predicted by deviant neuro-cognitive functioning, OR 6.8 (2.2-21.4), deviant language development, OR 5.9 (1.9-18.7) and impaired social interaction and communication, OR 3.8 (1.3-11.4). Unwanted pregnancy and parents' negative expectations of the child recorded in the first months of the child's life were significant predictors of relationship disturbances at 1(1/2) years. CONCLUSIONS: Predictors of neuro-developmental disorders and parent-child relationship disturbances can be identified in the first 10 months of life in children from the general population.

The prevalence of mental health problems in children 1(1/2) years of age - the Copenhagen Child Cohort 2000.

BACKGROUND: The Copenhagen Child Cohort, CCC 2000, was established to investigate developmental psychopathology prospectively from birth in a general population. METHODS: A random sample of 211 children from the CCC 2000 was investigated when the children were 1(1/2) years of age. The prevalence and associates of mental health problems and psychopathology were studied by clinical and standardised strategies, including videotape recordings, parent interviews and the following instruments: The Child Behavior Check List 1(1/2)-5 (CBCL 1(1/2)-5), The Infant Toddler Symptom Check List (ITSCL), Checklist for Autism in Toddlers (CHAT), Bayley Scales of Infant Development II (BSID II), The Parent Child Early Relationship Assessment (PC ERA) and Parent Infant Relationship Global Assessment Scale (PIR-GAS). RESULTS: Mental health problems according to International Classification of Diseases (ICD-10) and Diagnostic Classification Zero to Three (DC 0-3) diagnoses were found in 16-18% of 1(1/2)-year-old children. Most common were disturbances of emotion, behaviour and eating and the DC 0-3 diagnosis of regulatory disorder. Parent-child relationship disturbances were found in 8%. High psychosocial risk was significantly associated with emotional and behavioural disorders (OR 3.1 95% (1.2-8.1)) and disturbed parent-child relationship (OR 5.0 95% (1.6-16.0)). The strongest association of risk was found between relationship disorders and emotional and behavioural disorders (OR 11.6 95% (3.8-37.5)). CONCLUSIONS: The prevalence and distribution of psychopathology in 1(1/2)-year-old children seem to correspond to the distributions among older children. Disturbances in parent-child relationship have a key position in the risk mechanisms in early child psychopathology.

Failure to thrive: the prevalence and concurrence of anthropometric criteria in a general infant population.

BACKGROUND: Failure to thrive (FTT) in early childhood is associated with subsequent developmental delay and is recognised to reflect relative undernutrition. Although the concept of FTT is widely used, no consensus exists regarding a specific definition, and it is unclear to what extent different anthropometric definitions concur. OBJECTIVE: To compare the prevalence and concurrence of different anthropometric criteria for FTT and test the sensitivity and positive predictive values of these in detecting children with "significant undernutrition", defined as the combination of slow conditional weight gain and low body mass index (BMI). METHODS: Seven criteria of FTT, including low weight for age, low BMI, low conditional weight gain and Waterlow's criterion for wasting, were applied to a birth cohort of 6090 Danish infants. The criteria were compared in two age groups: 2-6 and 6-11 months of life. RESULTS: 27% of infants met one or more criteria in at least one of the two age groups. The concurrence among the criteria was generally poor, with most children identified by only one criterion. Positive predictive values of different criteria ranged from 1% to 58%. Most single criteria identified either less than half the cases of significant undernutrition (found in 3%) or included far too many, thus having a low positive predictive value. Children with low weight for height tended to be relatively tall. CONCLUSIONS: No single measurement on its own seems to be adequate for identifying nutritional growth delay. Further longitudinal population studies are needed to investigate the discriminating power of different criteria in detecting significant undernutrition and subsequent outcomes.

[Cataract--an initial symptom of diabetes mellitus in a 14-year old girl]. / Katarakt--debutsymptom på diabetes mellitus hos 14-årig pige.

A 14-year-old girl presented with cataract as an initial sign of IDDM. Before the diagnosis of DM, she showed no acute symptoms, including ketoacidosis. Retrospectively, there had been faint signs of polyuria, polydipsia, and nycturia. Diabetic cataract is a rare complication in young diabetics and is usually associated with long-standing DM and poor metabolic control. Previous cases have a striking resemblance to our patient, thus suggesting that a small group of young diabetics have weak symptoms, but are nevertheless at great risk of developing diabetic complications.

Occurrence and distribution of blackish staining on the crowns of human teeth obtained from an archeological excavation of a medieval site in Norway.

An excavation in Trondheim, Norway, in 1984-85, uncovered a part of the medieval (1100-1600) cemetery of St Olav's Church. Of 388 excavated skeletons, 248 had skulls where the condition of the jaws and teeth allowed examination. In 51 of these skulls the teeth exhibited a characteristic blackish staining. A higher percentage of affected skulls was found in areas with organic, woodchip layers than in areas with gravelly sand. Affected skulls tended to have a high percentage of their teeth stained, but the staining tended to be restricted to only one or two of the three tooth surfaces scored. Posterior teeth were more often affected than anterior teeth, the occlusal/incisal part more often than the cervical part, and the buccal/labial part more often than the lingual part. Nonerupted third molars could also be stained. Staining seemed to be hampered by calculus. Occurrence of staining was independent of the presence or absence of a coffin and of coffin type. The extent of staining (% of stained surfaces within a dentition) was independent of sex and age. High correlation was found between all four jaw quadrants. There was no independence between color of the jawbone and occurrence of stained teeth. It was concluded that the staining phenomenon probably can be ascribed to factors in the soil. In vivo predisposing influences cannot be excluded.

Validity of the radiographic assessment of ankylosis. Evaluation of long-term reactions in 10 monkey incisors.

The accuracy and sensitivity of radiographic assessments of reactive processes in dental tissues were evaluated by comparison of radiographs and histologic sections. Experimental lesions inflicted on the roots of 10 monkey incisors had been observed by means of serially obtained radiographs over a period of 315 to 370 days. The material was used for evaluation of radiographic assessment of ankylosis. For comparative purposes, assessment of the experimental lesion penetrating to the pulp and periapical radiolucency was added. True and falsely positive or negative recordings formed the basis for calculation of the accuracy and sensitivity of the radiographic assessment. The sensitivity, or the observers' ability to detect the actual changes, was high for pulp penetration, intermediate for inflammation, and low for ankylosis.

Premaxillary hyperdontia in medieval Norwegians: a radiographic study.

An excavation of a part of the graveyard of St Olav's church, Trondheim, Norway, uncovered 389 tombs from the medieval period (1100-1600). Radiographic examination of 140 skulls with an intact premaxilla revealed hyperdontia in the form of a mesiodens in two (1.4%) cases. This is within the same range as similar medieval and present Nordic populations. Change in functional pattern does not seem to influence the prevalence.

Comparison of oral radiographic findings among 35-year-old Oslo citizens in 1973 and 1984.

The purpose of the present study was to evaluate a variety of radiographically detectable conditions found on orthopantomograms of 141 individuals as a part of an oral health survey of 35-year-old Oslo citizens, born 1949. Radiographic findings were recorded and compared with those of a similar study made in 1973. The findings revealed a statistically significant reduction in the prevalence of marginal bone loss. The frequencies of endodontically treated teeth and teeth with apical radiolucencies were unchanged.

Experimental transplantation of teeth to simulated maxillary alveolar clefts.

A total of 14 teeth were transplanted to simulated alveolar clefts in 5 monkeys. Autogenous cancellous bone was grafted to the cleft together with the tooth in ten instances. Healing processes were observed 216 or 271 days postoperatively. Another group of four teeth were transplanted in the cleft areas 133 days after bone grafting. These teeth were observed for 138 days before sacrifice. Radiological and histological findings support previous reports on adverse effects to dental tissues when placed in direct contact with fresh transplanted bone. Root resorption and ankylosis occurred to a large extent. Establishment of a normal periodontal membrane could, however, be observed when the tooth was transplanted to an area grafted 4 months previously. An interval before tooth transplantation allowing the cancellous graft to organize and bone to remodel seems to be indicated.

Changing positions of supernumerary teeth in the premaxilla: a radiographic study.

To evaluate possible change of position of unerupted supernumerary teeth in the premaxilla, thirty-one patients were followed clinically and radiographically. Alteration in position could be observed in fourteen cases. Occasionally, migration of supernumerary teeth may occur if surgical intervention is postponed, resulting in a more accessible position.

Endotoxinemia and thrombocytopenia during neonatal necrotizing enterocolitis.

Thrombocytopenia frequently complicates neonatal necrotizing enterocolitis (NEC) and has been postulated to result from absorption of bacterial endotoxins from the injured gut. The authors tested blood obtained during 47 episodes of NEC for endotoxin-like activity (ELA), using a Limulus amoebocyte lysate assay and found 23 patients (49%) had positive results. Concentrations of ELA in plasma ranged from 0.26 to 300 ng/mL of Escherichia coli equivalent activity, with a geometric mean of 1.1 ng/mL. Serial platelet measurements were available from 40 infants, 11 (28%) of whom had nadir counts below 100,000/mm3 following NEC onset. Nine of 19 infants (47%) with ELA in plasma and only 2 of 21 without (9.5%, P less than 0.05) developed thrombocytopenia, suggesting that endotoxinemia may indeed contribute to platelet depletion during NEC.