Prevalence of the ABCB1-1Δ gene mutation in a sample of New Zealand Huntaway dogs.

AIMS: To determine the prevalence of the ATP Binding Cassette Subfamily B Member 1-1Δ mutation (ABCB1-1Δ; previously Multidrug Resistance 1 (MDR1) mutation) in a cohort of New Zealand Huntaway dogs. MATERIALS AND METHODS: Samples were opportunistically collected from Huntaway dogs (n = 189) from throughout New Zealand. Buccal swabs were collected from 42 Huntaways from the Wairarapa region and 147 blood samples from Huntaways from the Gisborne, Waikato, Manawatu/Whanganui, Hawkes Bay, Canterbury and Otago regions. DNA was extracted from all samples and tested for the presence of the ABCB1-1Δ allele. RESULTS: Of 189 Huntaway dogs that were tested, two were found to be heterozygous carriers of the ABCB1-1Δ allele and the remaining 187/189 dogs were homozygous for the wild type allele. No dogs homozygous for the mutation were identified. CONCLUSIONS AND CLINICAL RELEVANCE: The results of this study show that the ABCB1-1Δ allele is present in Huntaway dogs. The low prevalence in this convenience sample suggests that the prevalence of this allele in the Huntaway population is likely to be low. We recommend that veterinary clinicians discuss the potential for this mutation in Huntaways with dog owners including the clinical implications for dogs that are homozygous for the mutated allele and the potential for testing for the mutation, as they would do for other known mutations.

Assessment and quantification of sources of variability in breast apparent diffusion coefficient (ADC) measurements at diffusion weighted imaging.

PURPOSE: Apparent Diffusion Coefficient (ADC) measurements are increasingly used for assessing breast cancer response to neoadjuvant chemotherapy although little data exists on ADC measurement reproducibility. The purpose of this work was to investigate and characterise the magnitude of errors in ADC measures that may be encountered in such follow-up studies- namely scanner stability, scan-scan reproducibility, inter- and intra- observer measures and the most reproducible measurement of ADC. METHODS: Institutional Review Board approval was obtained for the prospective study of healthy volunteers and written consent acquired for the retrospective study of patient images. All scanning was performed on a 3.0-T MRI scanner. Scanner stability was assessed using an ice-water phantom weekly for 12 weeks. Inter-scan repeatability was assessed across two scans of 10 healthy volunteers (26-61 years; mean: 44.7 years). Inter- and intra-reader analysis repeatability was measured in 52 carcinomas from clinical patients (29-70 years; mean: 50.0 years) by measuring the whole tumor ADC value on a single slice with maximum tumor diameter (ADCS) and the ADC value of a small region of interest (ROI) on the same slice (ADCmin). Repeatability was assessed using intraclass correlation coefficients (ICC) and coefficients of repeatability (CoR). RESULTS: Scanner stability contributed 6% error to phantom ADC measurements (0.071×10(-3)mm(2)/s; mean ADC=1.089×10(-3)mm(2)/s). The measured scan-scan CoR in the volunteers was 0.122×10(-3)mm(2)/s, contributing an error of 8% to the mean measured values (ADCscan1=1.529×10(-3)mm(2)/s; ADCscan2=1.507×10(-3)mm(2)/s). Technical and clinical observers demonstrated excellent intra-observer repeatability (ICC>0.9). Clinical observer CoR values were marginally better than technical observer measures (ADCS=0.035×10(-3)mm(2)/s vs. 0.097×10(-3)mm(2)/s; ADCmin=0.09×10(-3)mm(2)/s vs. 0.114×10(-3)mm(2)/s). Inter-reader ICC values were good 0.864 (ADCS) and fair 0.677 (ADCmin). Corresponding CoR values were 0.202×10(-3)mm(2)/s and 0.264×10(-3)mm(2)/s, respectively. CONCLUSIONS: Both scanner stability and scan-scan variation have minimal influence on breast ADC measurements, contributing less than 10% error of average measured ADC values. Measurement of ADC values from a small ROI contributes a greater variability in measurements compared with measurement of ADC across the whole visible tumor on one slice. The greatest source of error in follow-up studies is likely to be associated with measures made by multiple observers, and this should be considered where multiple measures are required to assess response to treatment.

Technical assessment of whole body angiography and cardiac function within a single MRI examination.

AIM: To evaluate a combined protocol for simultaneous cardiac MRI (CMR) and contrast-enhanced (CE) whole-body MR angiography (WB-MRA) techniques within a single examination. MATERIALS AND METHODS: Asymptomatic volunteers (n = 48) with low-moderate risk of cardiovascular disease (CVD) were recruited. The protocol was divided into four sections: (1) CMR of left ventricle (LV) structure and function; (2) CE-MRA of the head, neck, and thorax followed by the distal lower limbs; (3) CMR LV "late gadolinium enhancement" assessment; and (4) CE-MRA of the abdomen and pelvis followed by the proximal lower limbs. Multiple observers undertook the image analysis. RESULTS: For CMR, the mean ejection fraction (EF) was 67.3 ± 4.8% and mean left ventricular mass (LVM) was 100.3 ± 22.8 g. The intra-observer repeatability for EF ranged from 2.1-4.7% and from 9-12 g for LVM. Interobserver repeatability was 8.1% for EF and 19.1 g for LVM. No LV delayed myocardial enhancement was observed. For WB-MRA, some degree of luminal narrowing or stenosis was seen at 3.6% of the vessel segments (involving n = 29 of 48 volunteers) and interobserver radiological opinion was consistent in 96.7% of 1488 vessel segments assessed. CONCLUSION: Combined assessment of WB-MRA and CMR can be undertaken within a single examination on a clinical MRI system. The associated analysis techniques are repeatable and may be suitable for larger-scale cardiovascular MRI studies.

Quantitative analysis of cardiac left ventricular variables obtained by MRI at 3 T: a pre- and post-contrast comparison.

Short-axis cine images are acquired during cardiac MRI in order to determine variables of cardiac left ventricular (LV) function such as ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and LV mass. In cardiac perfusion assessments this imaging can be performed in the temporal window between first pass perfusion and the acquisition of delayed enhancement images in order to minimise overall scanning time. The objective of this study was to compare pre- and post-contrast short-axis LV variables of 15 healthy volunteers using a two-dimensional cardiac-gated segmented cine true fast imaging with steady state precession sequence and a 3.0 T MRI unit in order to determine the possible effects of contrast agent on the calculated cardiac function variables. Image analysis was carried out using semi-automated software. The calculated mean LV mass was lower when derived from the post-contrast images, relative to those derived pre-contrast (102 vs 108.1 g, p<0.0001). Small but systematic significant differences were also found between the mean pre- and post-contrast values of EF (69.4% vs 68.7%, p<0.05), EDV (142.4 vs 143.7 ml, p<0.05) and ESV (44.2 vs 45.5 ml, p<0.005), but no significant differences in SV were identified. This study has highlighted that contrast agent delivery can influence the numerical outcome of cardiac variables calculated from MRI and this was particularly noticeable for LV mass. This may have important implications for the correct interpretation of patient data in clinical studies where post-contrast images are used to calculate LV variables, since LV normal ranges have been traditionally derived from pre-contrast data sets.

Knowledge about the Scottish Mental Health Act in a general hospital setting.

BACKGROUND: Clinical experience suggests that non-psychiatrists' knowledge of mental health legislation in relation to emergency detention is inadequate. However, most non-psychiatrists will use this legislation at some point in their career. METHODOLOGY: A questionnaire about emergency detention legislation was circulated to non-psychiatric medical staff to test their knowledge of the provisions relevant to the general hospital. RESULTS: Two hundred and seventy four medical staff replied (a response rate of 82%). Results showed that an understanding of detention procedures and applicability were markedly deficient, irrespective of grade, specialty or experience. CONCLUSION: The results indicate a need for increased education and awareness about emergency detention legislation especially in view of the implementation of the Mental Health (Scotland) Act (2003).

The chemokine CXCL12 promotes survival of postmitotic neurons by regulating Rb protein.

Postmitotic neurons need to keep their cell cycle under control to survive and maintain a differentiated state. This study aims to test the hypothesis that the chemokine CXCL12 regulates neuronal survival and differentiation by promoting Rb function, as suggested by previous studies showing that CXCL12 protects neurons from apoptosis induced by Rb loss. To this end, the effect of CXCL12 on Rb expression and transcriptional activity and the role of Rb in CXCL12-induced neuronal survival were studied. CXCL12 increases Rb protein and RNA levels in rat cortical neurons. The chemokine also stimulates an exogenous Rb promoter expressed in these neurons and counteracts the inhibition of the Rb promoter induced by E2F1 overexpression. Furthermore CXCL12 stimulates Rb activity as a transcription repressor. The effects of CXCL12 are mediated by its specific receptor CXCR4, and do not require the presence of glia. Finally, shRNA studies show that Rb expression is crucial to the neuroprotective activity of CXCL12 as indicated by NMDA-neurotoxicity assays. These findings suggest that proper CXCR4 stimulation in the mature CNS can prevent impairment of the Rb-E2F pathway and support neuronal survival. This is important to maintain CNS integrity in physiological conditions and prevent neuronal injury and loss typical of many neurodegenerative and neuroinflammatory conditions.

Psychosocial and behavioral pre-treatment predictors of weight loss outcomes.

OBJECTIVE: This study tested whether baseline behavioral and psychological variables predict weight and fat loss among overweight, non-obese individuals participating in a six-month calorie restriction trial. Participants (N=48) were randomly assigned to four groups, three of which included a calorie restriction program and one of which served as a healthy diet weight maintenance control. For the purposes of this study, data were analyzed only for participants assigned to the three calorie restriction groups (n=36). Ten psychological and behavioral measures were investigated through principal components factor analysis to examine whether these measures were assessing similar or distinct psychological and behavioral constructs. Based on the obtained six-factor solution, one measure from each domain was selected for inclusion in hierarchical regression analyses, which was used to test the relative importance of psychosocial and behavioral variables in predicting percent weight and fat loss over six months. After controlling for demographic and treatment variables, the behavioral and psychological measures of negative mood states, poor psychosocial functioning, and somatic symptoms were associated with less weight loss (R2=0.68, p<0.001) and fat loss (R2=0.65, p<0.001) over six months. Among overweight individuals, poor psychological adjustment, somatic symptoms, and negative mood states appear to form a psychosocial profile that is predictive of less weight and fat loss in calorie restriction programs.

Reformulation of the Children's Eating Attitudes Test (ChEAT): factor structure and scoring method in a non-clinical population.

The primary aims of this study were to empirically test the factor structure of the Children's Eating Attitudes Test (ChEAT) through both exploratory and confirmatory factor analyses and to interpret the factor structure of the ChEAT within the context of a new scoring method. The ChEAT was administered to 728 children in the 2nd through 6th grades (from five schools) at two different time points. Exactly half the students were male and half were female. To the best of our knowledge, this is the first study to empirically test the merits of an alternative 6-point scoring system as compared to the traditionally used 4-point scoring system. With the new scoring procedure, the skewness for all factor scores decreased, which resulted in increased variance in the item scores, as well as the total ChEAT score. Since the internal consistency of two factors in a recently proposed model was not acceptable (<0.60), this model did not adequately fit our data. Thus, exploratory and confirmatory factor analyses were conducted. A 6-factor solution based on a 20-item version was found to best fit the data and have the best internal reliability. The six factors were labeled: 1) overconcern with body size, 2) dieting, 3) food preoccupation, 4) social pressure to gain weight, 5) vomiting, and 6) caloric awareness and control. The obtained factor solution had considerable overlap with the original factor analysis performed on the 26-item Eating Attitudes Test and with the factor structure of the ChEAT reported by previous investigations. Intercorrelations among the factors suggested three higher order constructs. These findings indicate that the ChEAT subscales may be sufficiently stable to allow use in non-clinical samples of children.

Efficacy of an internet-based behavioral weight loss program for overweight adolescent African-American girls.

OBJECTIVE: This randomized controlled trial tested the efficacy of an internet-based lifestyle behavior modification program for weight management in African-American girls. DESIGN: African-American girls were randomly assigned to an interactive behavioral internet program or an internet health education program, the control condition. The behavioral intervention included internet counseling and was highly interactive. The control intervention was a passive (non-interactive) educational program. Parents were also participants in the study. Participants in both treatment groups met in face-to-face sessions on four occasions over the first 12 weeks of a 6-month intervention. SUBJECTS: The study enrolled 57 African-American adolescent girls (ages 11 to 15 years) who were overweight or obese and had at least one biological parent who was obese [body mass index (BMI) >30 kg/m2]. Of the 57 participants, 50 (88%) completed the 6-month trial. MEASUREMENTS: Outcome data, including BMI, body weight, body composition, dietary intake, and weight loss behaviors were collected at baseline and 6-months later. A computer server tracked utilization of the websites. Participation in the program was measured by number of "hits" on the website. RESULTS: Compared to the control condition, adolescents in the behavioral treatment lost more body fat (group difference =1.6% body fat) and parents lost significantly more body weight (group difference =2.1 kg). Utilization of the behavioral website by adolescents and parents was associated with positive outcome. Dietary fat intake was lowered for adolescents and parents in the behavioral treatment group. CONCLUSION: An internet-based behavioral intervention was superior to internet-based health education and yielded decreased body fat for adolescent girls and decreased body weight for parents.

Percent body fat measured by BIA and DEXA in obese, African-American adolescent girls.

OBJECTIVE: To compare the estimation of body fat between bioelectrical impedance analysis (BIA) and dual energy X-ray absorptiometry (DEXA) in overweight, African-American female adolescents. SUBJECTS: In total, 54 African-American adolescent female subjects were recruited for Study 1. Each adolescent's body mass index was greater than the 85th percentile and their average body fat was 45% according to DEXA. A total of 26 African-American adolescent female subjects were available for Study 2, and had an average body fat of 26% according to DEXA. MEASUREMENTS: Percent body fat was measured by DEXA and BIA. Seven different BIA equations were tested. Both sets of data were analyzed using Bland-Altman regression analyses, utilizing percent body fat measured by DEXA as the criterion. RESULTS: The Kushner equation provided estimates that were unaffected by body fat in both studies. Estimates were unbiased when applied to the exclusively overweight sample and biased when utilized with the separate sample of normal weight and obese girls. The remaining equations were biased, provided inconsistent estimates across body weight, or were biased and provided inconsistent estimates. Ethnicity-specific and ethnicity-combined equations performed similarly in the obese sample, but became more disparate when applied to a sample encompassing a wider body weight range. The limits of agreement between all BIA equations and the DEXA estimates ranged from 6 to 9%. CONCLUSION: The study suggests that the Kushner BIA equation is appropriate for use with African-American female adolescents across the weight spectrum, while the majority of BIA equations underestimated percent body fat as body fat increased.

Health and appearance concerns in young Caucasian and African-American women.

OBJECTIVE: The primary aim of this study was to examine the health- and appearance-related concerns of young African-American and Caucasian females. RESEARCH METHODS: Participants were twenty Caucasian and twenty African-American college women, who were matched on age and BMI. All participants were administered the Multidimensional Body-Self Relations Questionnaire (MBSRQ), a demographics instrument, and a short inventory to assess concerns about health, appearance, and weight management, in a single testing session; height and weight data were self-reported. RESULTS: African-American women and Caucasian women were not significantly different in their level of health consciousness or perception of health; however, African-American women were significantly more satisfied with their physical appearance in comparison to Caucasian women. Among African-American women, perception of health and level of health consciousness were highly related; this relationship was not found in Caucasian women. In addition, perception of health was related to satisfaction with appearance in both groups, although the relationship was stronger among African-Americans. Among Caucasian women, satisfaction with physical appearance was highly correlated with perception of weight status (from underweight to very overweight); this relationship was not found among African-American females. An inverse relationship between body mass index (BMI) and appearance evaluation was found only for Caucasian females. DISCUSSION: These findings suggest that, on the whole, young African-American and Caucasian college females report similar evaluations of health and values placed on appearance and health, and differ primarily in terms of satisfaction with physical appearance.

Reduced neurocognition in children who snore.

Obstructive sleep apnea syndrome (OSAS) has been associated with reduced neurocognitive performance in children, but the underlying etiology is unclear. The aim of this study was to evaluate the relationship between hypoxemia, respiratory arousals, and neurocognitive performance in snoring children referred for adenotonsillectomy. Thirteen snoring children who were referred for evaluation regarding the need for adenotonsillectomy to a children's hospital otolaryngology/respiratory department underwent detailed neurocognitive and polysomnographic (PSG) evaluation. PSGs were evaluated for respiratory abnormalities and compared with 13 nonsnoring control children of similar age who were studied in the same manner. The snoring children had an obstructive respiratory disturbance index within normal range (mean obstructive apnea/hypopnea index, 0.6/hr). Despite this, several domains of neurocognitive function were reduced in the snoring group. These included mean verbal IQ scores (snorers 92.6 vs. nonsnorers 110.2, P < 0.001), mean global IQ scores (snorers 96.7 vs. nonsnorers 110.2, P < 0.005), mean selective attention scores (snorers 46.4 vs. nonsnorers 11.8, P < 0.001), mean sustained attention scores (snorers 8.0 vs. nonsnorers 2.2, P = 0.001), and mean memory index (snorers 95.2 vs. nonsnorers 112.1, P = 0.001). There was a direct relationship between number of mild oxygen desaturations of > or = 3%, obstructive hypopneas with > or = 3% oxygen desaturations, and respiratory arousals and severity of neurocognitive deficits, with the greatest effect being on memory scores. The disruption of sleep in snoring children produced by relatively mild changes in oxygen saturation or by increases in respiratory arousals may have a greater effect on neurocognitive function than hitherto appreciated. A possible explanation for these neurocognitive deficits may be the combination of the chronicity of sleep disruption secondary to snoring which is occurring at a time of rapid neurological development in the first decade of life. Future studies need to confirm the reversal of these relatively mild neurocognitive decrements post adenotonsillectomy.

Chloroplast inheritance and DNA variation in sweet, sour, and ground cherry.

Sour cherry (Prunus cerasus L.) is an allotetraploid and both sweet cherry (P avium L.) and ground cherry (P. fruticosa Pall.) are the proposed progenitor species. The study investigated the maternal species origin(s) of sour cherry using chloroplast DNA (cpDNA) markers and a diverse set of 22 sweet, 25 sour, and 7 ground cherry selections. Two cpDNA restriction fragment length polymorphisms (RFLPs) and one polymerase chain reaction (PCR) fragment length polymorphism were identified among the 54 selections. The three polymorphisms considered together resolved four haplotypes. Analysis of sour cherry progeny indicated that the chloroplast genome is maternally inherited and therefore appropriate to use in determining maternal phylogenetic relationships. Ground cherry was found more likely than sweet cherry to be the maternal progenitor species of sour cherry since 23 of 25 of the sour cherry selections had the most prevalent ground cherry haplotype. However, the other two sour cherry selections tested had the most prevalent sweet cherry haplotype and a wild French sweet cherry selection had the most prevalent ground cherry haplotype. The results underscore the importance of using diverse Prunus germplasm to investigate phylogenetic relationships.

Plasma leptin, energy intake and hunger following total hip replacement surgery.

1. This study aimed to investigate the possible role of leptin in post-traumatic anorexia by making pre- and post-operative (0-8 days) measurements of circulating leptin concentrations in six patients undergoing elective total hip replacement for osteoarthritis. 2. Mean daily hunger rating (four categories) and food intake (assessed by food record charts) were measured pre-operatively, as well as post-operatively for the first 5 days (days 0-5). Leptin concentrations, circulating metabolites [glucose, non-esterified fatty acids, glutamine and 3-hydroxybutyrate] and insulin and cortisol concentrations were measured pre-operatively (day 0) and post-operatively (days 1, 2, 3, 5 and 8). 3. Mean leptin concentrations were significantly increased only on day 1 (56% increase compared with pre-operative values, P < 0.009), whereas food intake (only 0.6 MJ on day 0) and hunger (5/6 patients 'not hungry' on day 0) only gradually improved over the next few days. (The energy intake over the first 5 days was 56% of the pre-operative value.) 4. Circulating insulin and cortisol concentrations were elevated on day 1 compared with pre-operative values on day 0 (P < 0.05). Of the measured metabolites implicated in the control of food intake, circulating non-esterified fatty acids and 3-hydroxybutyrate were not significantly altered in the post-operative period, but significant hyperglycaemia was noted on day 1 compared with day 0 pre-operatively (8.8 compared with 6.4 mmol/l glucose; P < 0.01). 5. It is concluded that circulating leptin is involved in the early (< 24 h) acute-phase response after moderately severe surgical trauma (characterized biochemically by a substantial acute-phase protein response, hypoalbuminaemia, hyperglycaemia and hypoglutaminaemia). Therefore, leptin may be implicated in post-traumatic anorexia, although other factors are likely to be involved, especially after the first 24 h when circulating leptin concentrations are no longer elevated.

Photo-initiated peroxidation of lipids in micelles by azaaromatics.

The monoazaaromatics, pyridine (1), hexyl nicotinate (2), and quinoline (3) and diazaaromatics, pyrimidine (4) and purine (5), readily act as photo-initiators for the peroxidation of methyl linoleate in 0.50 M SDS at 37 degrees C giving free radical chain oxidations of linoleate. Quantitative kinetic runs on the order in substate, RH, and in the rate of chain initiation, Ri, showed that the classical rate law for autoxidation, -d[O2]/dt = (kp/(2 kt 1/2))[RH] x Ri 1/2, is applicable to these photo-initiated oxidations. The oxidizability of methyl linoleate under these conditions is 2.92 x 10(-2) M-1/2 s-1/2. These peroxidations were inhibited by chromanol phenolic antioxidants of the vitamin E class, such as lipid-soluble 2,2,5,7,8-pentamethyl-6-hydroxychroman (PMHC) and water-soluble 2-carboxy- 2,5,7,8-tetramethyl-6-hydroxychroman (Trolox) and derived rate constants for inhibition of peroxidation were kinh (PMHC) = 4.35 x 10(4) M-1 s-1 and k(inh) (Trolox) = 2.81 x 10(4) M-1 s-1 during inhibited oxidation of methyl linoleate photo-initiated by 4. The products from photo-initiated peroxidation of methyl linoleate by 1 through 5 were determined by reduction and high-performance liquid chromatography analyses to be the 9- and 13-positional hydroperoxides of the four geometrical isomers: cis-9, trans-11 (6), trans-10, cis-12 (7), trans-9, trans-11 (8), and trans-10, trans-12 (9)-octadecadienoates typical of the free radical chain mechanism of lipid peroxidation. Products from dye-sensitized oxidation by Methylene Blue or Rose Bengal of methyl linoleate gave a product distribution of six hydroperoxides typical of oxidation by singlet oxygen. Thermal or photo-initiated peroxidation of methyl linoleate in SDS gave some selectivity of oxidation at the 13-position of the linoleate chain. The ratio of 13- to 9-oxidation varied in the range 1.23 to 1.14 as the cis/trans to trans/trans ratio of geometrical isomers varied from 0.44 to 1.25 during photooxidation of increased amounts of linoleate in SDS. This selectivity is attributed to loss of the pseudo symmetry around the pentadienyl system in the lipid chain in the SDS system during the peroxidation.

Ideal versus ought predilections for approach and avoidance: distinct self-regulatory systems.

Two studies using different paradigms activated either ideal self-guides (a person's hopes or wishes) or ought self-guides (a person's sense of duty and responsibility) and measured Ss' concern with different forms of self-regulation: approaching matches to desired end states or mismatches to undesired end states and avoiding mismatches to desired end states or matches to undesired end states. A 3rd study asked ideal versus ought discrepant Ss to select among alternative strategies for friendship. The results suggest that a concern with approach is greater for ideal than ought self-regulation, whereas a concern with avoidance is greater for ought than ideal self-regulation.