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Maternal mental state language is thought to influence children's mental state language and sociocognitive understanding (e.g., theory of mind), but the mechanism is unclear. The current study examined the longitudinal development of mental state language in mother-child interactions. The methodology included assessments of the child and/or mother-child dyad at six time points between 12 to 52 months of the child's age. Measures determined child's attachment style and language abilities, and mental state language used by mother and child during a block-building task. Results showed that (a) mental state talk, including belief and desire language, increased over time; (b) there were differences between the type of mental state words used by the mother in insecure versus secure dyads; (c) there were differences in patterns of mental state words used in both mothers and children in insecure versus secure dyads; and (d) attachment appeared to exert a consistent influence over time.

J. Neurochem. (2011) 119, 604–616. Abstract Fatty acids such as eicosapentaenoic acid (EPA) have been shown to be beneficial for neurological function and human health. It is widely thought that oxidation products of EPA are responsible for biological activity, although the specific EPA peroxidation product(s) which exert these responses have not yet been identified. In this work we provide the first evidence that the synthesized representative cyclopentenone IsoP, 15-A3t-IsoP, serves as a potent inhibitor of lipopolysaccharide-stimulated macrophage activation. The anti-inflammatory activities of 15-A3t-IsoP were observed in response not only to lipopolysaccharide, but also to tumor necrosis factor alpha and IL-1b stimulation. Subsequently, this response blocked the ability of these compounds to stimulate nuclear factor kappa b (NFκB) activation and production of proinflammatory cytokines. The bioactivity of 15-A3t-IsoP was shown to be dependent upon an unsaturated carbonyl residue which transiently adducts to free thiols. Site directed mutagenesis of the redox sensitive C179 site of the Ikappa kinase beta subunit, blocked the biological activity of 15-A3t-IsoP and NFκB activation. The vasoprotective potential of 15-A3t-IsoP was underscored by the ability of this compound to block oxidized lipid accumulation, a critical step in foam cell transformation and atherosclerotic plaque formation. Taken together, these are the first data identifying the biological activity of a specific product of EPA peroxidation, which is formed in abundance in vivo. The clear mechanism linking 15-A3t-IsoP to redox control of NFκB transcription, and the compound’s ability to block foam cell transformation suggest that 15-A3t-IsoP provides a unique and potent tool to provide vaso- and cytoprotection under conditions of oxidative stress.

Using quantitative PCR, DNA of Plasmodiophora brassicae, the causal agent of clubroot, was detected and quantified on canola, pea and wheat seeds, as well as on potato tubers, all harvested from clubroot-infested fields in Alberta, Canada. Quantifiable levels of infestation were found on seven of the 46 samples analysed, and ranged from

Lipid peroxidation of docosahexaenoic (22:6; n-3) acid (DHA) is elevated in the CNS in patients with Alzheimer's disease and in animal models of seizure and ethanol withdrawal. One product of DHA oxidation is trans-4-hydroxy-2-hexenal (HHE), a six carbon analog of the n-6 fatty acid derived trans-4-hydroxy-2-nonenal (HNE). In this work, we studied the neurotoxic potential of HHE. HHE and HNE were toxic to primary cultures of cerebral cortical neurons with LD(50)'s of 23 and 18 micromol/L, respectively. Toxicity was prevented by the addition of thiol scavengers. HHE and HNE depleted neuronal GSH content identically with depletion observed with 10 micromol/L of either compound. Using an antibody raised against HHE-protein adducts, we show that HHE modified specific proteins of 75, 50, and 45 kDa in concentration- and time-dependent manners. The time-dependent formation of HHE differed from that of F4-neuroprostanes following in vitro DHA oxidation likely as a result of the different oxidation pathways involved. Using purified mitochondrial aldehyde dehydrogenase ALDH5A, we found that HHE was oxidized 6.5-fold less efficiently than HNE. Our data demonstrate that HHE and HNE have similarities but also differences in their neurotoxic mechanisms and metabolism.

Greenhouse trials conducted in 2003 and 2004 investigated the impact of trichothecenes on the severity of seedling blight and root rot in common wheat (Triticum aestivum), durum wheat (Triticum turgidum var. durum), barley (Hordeum vulgare) and triticale (×Triticosecale 6x) using two trichothecene-producing and two trichothecene-nonproducing Fusarium graminearum strains. In 2003 seedling emergence and survival following soil infestation of the trichothecene-producing strain (Gz3639) were significantly reduced compared with the trichothecene-nonproducing strain (GzT40), while root-rot incidence and severity were increased significantly. In 2004, two trichothecene-producing strains (Gz3639 and GzT106) reduced seedling emergence and survival (P ≤ 0·01) in eight of 10 crops/cultivars based on single-degree-of-freedom contrasts. However, when results from all strains were combined no significant differences were observed between two trichothecene-producing and two trichothecene-nonproducing F. graminearum strains. Inoculation with GzT106, a trichothecene-producing ‘add-back’ strain, resulted in more severe root rot symptoms in eight of 10 cultivars (P ≤ 0·01–0·05) and lower seedling emergence and survival in seven of 10 cultivars (P ≤ 0·01–0·10), compared with the wild-type parental strain Gz3639. The presence of trichothecenes may play an important role in the aggressiveness of F. graminearum.

The adaptive significance of sexual reproduction remains as an unsolved problem in evolutionary biology. One promising hypothesis is that frequency-dependent selection by parasites selects for sexual reproduction in hosts, but it is unclear whether such selection on hosts would feed back to select for sexual reproduction in parasites. Here we used individual-based computer simulations to explore this possibility. Specifically, we tracked the dynamics of asexual parasites following their introduction into sexual parasite populations for different combinations of parasite virulence and transmission. Our results suggest that coevolutionary interactions with hosts would generally lead to a stable coexistence between sexual parasites and a single parasite clone. However, if multiple mutations to asexual reproduction were allowed, we found that the interaction led to the accumulation of clonal diversity in the asexual parasite population, which led to the eventual extinction of the sexual parasites. Thus, coevolution with sexual hosts may not be generally sufficient to select for sex in parasites. We then allowed for the stochastic accumulation of mutations in the finite parasite populations (Muller's Ratchet). We found that, for higher levels of parasite virulence and transmission, the population bottlenecks resulting from host–parasite coevolution led to the rapid accumulation of mutations in the clonal parasites and their elimination from the population. This result may explain the observation that sexual reproduction is more common in parasitic animals than in their free-living relatives.

The relative virulence of 109 Ascochyta isolates collected from pea fields in Alberta from 1996 to 1998 were evaluated on 10-day-old seedlings by the excised leaf-assay technique. Twenty-eight isolates were avirulent, while the others produced lesions of various sizes on pea leaves. DNA samples from 86 isolates were amplified by the RAPD technique using PCR with single primers. One dominant genotype of Ascochyta pisi was identified throughout Alberta, but variations in virulence were not clearly differentiated by the RAPD technique. Five Ascochyta isolates, four virulent and one avirulent, were used to assess the susceptibility of 20 field pea cultivars available in Alberta, including 13 yellow types and seven green types. Based on symptom development, the yellow-type cultivars Swing, Eiffel and Delta, and the green-type cultivar Orb, were the most susceptible. Of yellow-type cultivars, Voyageur, Carneval and Montana were most resistant to Ascochyta infection.

Lipids from the paracloacal glands of adult Chinese alligators (Alligator sinensis) were analyzed by gas chromatography/mass spectrometry. Acetates, aliphatic alcohols, free fatty acids and waxes consisting primarily of hexadecanoates were indicated in the secretions of males and females. Cholesterol, a diterpene hydrocarbon, and a diterpene ketone were detected in secretions of males but not in those of females. Lipids identified in the paracloacal secretions ofA. sinensis are compared with those reported from the American alligator and other crocodilians.

1. Efferent discharges were recorded from inspiratory and expiratory intercostal nerve filaments (T2-T10) in artificially ventilated, anaesthetized or decerebrate rabbits with or without vagotomy. 2. Hypocapnic apnoea was used to study the fractional end-tidal CO2 (FET,CO2)-dependent tonic discharges of the expiratory motoneurones, the FET,CO2 threshold for rhythm generation and the FET,CO2 response curve of both inspiratory and expiratory burst activity. 3. Incremental doses of morphine (e.g. 1 mg kg-1 I.V.) produced slowing of the respiratory rhythm due to prolongation of the expiratory duration and an elevation of the FET,CO2 threshold for rhythm generation. Eventually apnoea supervened with associated tonic firing of the expiratory motoneurones. At the elevated levels of FET,CO2 bursts of inspiratory activity, with concomitant phasic inhibition of the tonic expiratory activity, could occur either spontaneously or following sensory stimulation. The peak integrated activities of these bursts were closely similar to the values obtained for corresponding levels of FET,CO2 before the administration of morphine. 4. Tonic expiratory activity responded to increased levels of FET,CO2, as it had during hypocapnic apnoea prior to morphine, by an increased discharge frequency of single units or recruitment of new units. 5. All of these effects of morphine were immediately reversed by naloxone (100 micrograms kg-1). 6. Naloxone (greater than 100 micrograms kg-1), without pre-treatment with morphine, led to an increase in respiratory frequency due to a shortening of the expiratory duration and a dose-dependent reduction in the FET,CO2 threshold for rhythm generation. There was little alteration either in the inspiratory response to FET,CO2 during rhythm or in the FET,CO2 response of the expiratory output whether expressed as tonic activity during hypocapnic apnoea or phasic activity following the onset of rhythm. 7. Thus opiates act upon the mechanisms of rhythm generation without depressing the FET,CO2 drive as expressed either as phasic or tonic activation of the motoneurones.

Two previous studies measuring cerebrospinal fluid (CSF) hypocretin-1 (Hcrt) in patients with neurological illness and one series reporting on CSF Hcrt levels across gender and generation have found that, apart from a small subgroup of patients with Guillain-BarreSyndrome (GBS) with unde- tectable levels, CSF Hcrt did not differ significantly between neurological disease and normal controls (Kanbayashi et al. 2002a, 2002b; Ripley et al. 2001). Kanbayashi's group reported on 10 patients with GBS, seven with multiple sclerosis (MS), and six patients with Parkinson's disease, five with cerebral infarction and a further five with epilepsy (Kanbayashi et al. 2002a). Ripley et al. (2001) have studied a larger sample of patients with a wide range of neuro- logical diagnoses including Alzheimer's disease (n ¼ 24), intracranial neoplasms (n ¼ 17), MS (n ¼ 13), intracranial infections (n ¼ 32), head trauma (n ¼ 4), GBS (n ¼ 8) and chronic inflammatory demyelinating polyneuropathy (CIDP) (n ¼ 13), and subarachnoid haemorrhage (SAH) (n ¼ 35). Low levels of CSF Hcrt have been found in patients with SAH, acoustic schwannoma, and head trauma (Ripley et al. 2001). The authors suggest that this phenomenon might be explained by damage to and ⁄ or dysfunction of the hypotha- lamus. The role of Hcrt in neurological and psychiatric disorders is yet to be established. We have measured CSF Hcrt in our patient population to verify these previously published findings. Lumbar CSF was collected from 194 patients, 61 males and 133 females, with a variety of neurological diagnoses and including 15 control samples. The control group was drawn from samples collected during epidural procedures from women in early labour. The CSF Hcrt-1 was measured in crude CSF samples (no extraction procedure) (100 lL, dupli- cate) using a commercially available radioimmunoassay (RIA) kit (Phoenix Pharmaceuticals Inc., Belmont, CA, USA). Intra- assay variability was 3.6% and the detection limit was 40 pg mL )1 . Samples were drawn from patients aged 15- 80 years (mean age 42 ± 14 years) after obtaining informed consent for the lumbar puncture. Statistical analysis was made by using one-way analysis of variance (anova) and Fisher's PLSD, and Fisher's exact probability test. Hypocretin was detectable in all the specimens tested. The mean Hcrt for the entire sample (n ¼ 194) was 176 ± 53 pg mL )1 (mean ± SD; range: 44-302 pg mL )1 ). There was no significant difference between males (167 ± 55 pg mL )1 ; range: 44-302 pg mL )1 ) and females (180 ± 57 pg mL )1 ; range: 57-291 pg mL )1 ). Hypocretin levels in

SUMMARY Beating, a pulp treatment widely used in the paper industry, causes disruption of cell wall layers and fibrillation. Previous studies of the effects of beating on fibre morphology have used conventional methods of specimen preparation, with all the attendant problems of shrinkage and distortion during dehydration. Low-temperature scanning electron microscopy (LTSEM) therefore seemed to offer an ideal method for examining fully hydrated wood pulp fibres. Cryofixation of pulp followed by sublimation of superficial ice, however, is shown to generate artefacts indistinguishable from structures present in the samples. Fibrillar and membranous structures were generated in LTSEM-prepared sugar solutions; their presence in pulp samples was therefore attributed to the dissolved carbohydrates inherent in pulp suspensions. Since artefact and fact are currently impossible to distinguish in LTSEM-prepared pulp samples, it seems that the technique should be applied to wet paper or pulp samples with considerable circumspection.

SYNOPSIS This paper describes the rare occurrence of Cushing's syndrome in a female infant aged eleven weeks. An adrenal adenoma was found to be the cause, and its removal was followed by a return to a normal appearance. This patient is the first with this condition seen in this age group at the Royal Children's Hospital since 1948. The Hospital's experience with adrenal tumours since that time is also presented, together with a review of the recent literature.

SUMMARY– Sarcomere length in the longissimus dorsi muscles of 20 bovine animals was compared to other variables in predicting tenderness (Allo-Kramer shear) in two muscle positions (medial and lateral) and at four cooking temperatures (60, 64, 68 and 72°C). The medial muscle position was less tender, had shorter sarcomeres and had higher correlations between sarcomere length and tenderness than the lateral muscle position. In neither position did sarcomere length account for tenderness variation that was unaccounted for by combinations of other commonly-used carcass variables indicating that a single measure of sarcomere length at a given position is of little value in predicting tenderness if certain carcass parameters are known. Comparison of sarcomere length with resistance to shear across the cross section of 5 additional longissimus dorsi muscles showed that very small differences in contraction state were associated with marked differences in tenderness in restricted muscle areas. The study emphasizes the importance of post-rigor contracture to tenderness but indicates that several estimates are necessary to characterize a single muscle.

SUMMARY Studies were conducted on the muscle properties of pigs reared in one of several combinations of environmental temperature and humidity. Longissimus dorsi muscle of pigs reared in alternating temperatures (29 and 18°C) was inferior in structure to that of pigs reared in 29 or 18°C constant temperatures if the relative humidity was low (30%). High relative humidity (85%) during growth tended to improve muscle structure and tenderness (68 and 72°C cooking temperature), regardless of environmental temperature. Breed-treatment interactions for muscle structure score indicated that Poland China and Hampshire pigs differed in response to environment. Breed comparisons over all treatments revealed that muscle from Poland China pigs was less tender than muscle from Hampshire pigs when it was heated to 60°C. The data on tenderness suggest that the major environmental effects were exerted on the muscle constituents which are susceptible to high cooking temperatures (protein hardening range) whereas the breed differences were evident at low cooking temperatures (collagen shrinkage range).

SUMMARY– The influence of dietary regimen of 104 half-sib Angus steers allotted to 1 of 13 combinations of hay, corn silage and corn concentrate, and of slaughter weights of 284 vs. 340 kg and 409 vs. 454 kg (live weight) on processing qualities and palatability of beef was studied. Measurements included postmortem glycolytic activity, water- and fat-binding capacity, textural properties, cooking losses, flavor and juiciness of selected muscles. Results showed that feeding regimens had a greater effect than did slaughter weight on qualities studied. Corn silage in the early dietary regimen of cattle weighing 284 and 340 kg resulted in significantly lower pH values (5 and 45 min post-mortem), higher amounts of glycogen at slaughter and greater water- and fat-binding capacity as compared to hay. Similar effects of early diet were noted for 5- and 45-min pH and water-binding capacity in cattle fed to heavier weights (409 and 454 kg); however, in these animals the early-hay diet resulted in greater muscle glycogen deposition than the early-silage diet. Steaks from animals fed corn silage in the early period were determined to be more tender by both shear values and panel scores and were more juicy and flavorful than those from hay-fed animals. These differences in palatability due to early diet were still evident after the cattle had been fed to heavier (409 and 454 kg) weights. When steers weighing 409 and 454 kg were grouped together, the effects of feeding regimen during the intermediate period were considerably less pronounced than those of the early feeding period.

L'invalidite des noms d'especes des ouvrages de Forsskal et Aublet, selon les regles du code botanique poserait de graves problemes