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Selected AbstractsAge- and subcaste-related patterns of serotonergic immunoreactivity in the optic lobes of the ant Pheidole dentataDEVELOPMENTAL NEUROBIOLOGY, Issue 11 2008Marc A. Seid Abstract Serotonin, a biogenic amine known to be a neuromodulator of insect behavior, has recently been associated with age-related patterns of task performance in the ant Pheidole dentata. We identified worker age- and subcaste-related patterns of serotonergic activity within the optic lobes of the P. dentata brain to further examine its relationship to polyethism. We found strong immunoreactivity in the optic lobes of the brains of both minor and major workers. Serotonergic cell bodies in the optic lobes increased significantly in number as major and minor workers matured. Old major workers had greater numbers of serotonergic cell bodies than minors of a similar age. This age-related increase in serotonergic immunoreactivity, as well as the presence of diffuse serotonin networks in the mushroom bodies, antennal lobes, and central complex, occurs concomitantly with an increase in the size of worker task repertoires. Our results suggest that serotonin is associated with the development of the visual system, enabling the detection of task-related stimuli outside the nest, thus playing a significant role in worker behavioral development and colony-wide division of labor. © 2008 Wiley Periodicals, Inc. Develop Neurobiol, 2008. [source] Comparison of the effect of a cornstarch thickened formula and strengthened regular formula on regurgitation, gastric emptying and weight gain in infantile regurgitationDISEASES OF THE ESOPHAGUS, Issue 2 2007H.-C. Chao SUMMARY., The purpose of this study was to evaluate the efficacy of a specially selected cornstarch-supplemented formula on clinical symptoms, gastric emptying and weight gain in infants with regurgitation. We performed a prospective randomised trial evaluating the therapeutic efficacy of two different formula feedings (cornstarch-thickened formula, group A; 25% strengthened formula, group B) in 81 young infants with regurgitation/vomiting , 3 times/day. A Tc-99 m milk scintigraphy was performed at inclusion and after 2 months to quantify gastric emptying time; all studied infants underwent a 2-month period of clinical follow-up evaluating regurgitation and body weight gain. At inclusion, group A and B had a similar age and weight. After the 2-month period of intervention, regurgitation and vomiting had both greater decrease (both P < 0.001 at 1 and 2 months) in group A (from a score of 4.19 ± 1.71 to 0.93 ± 0.42) than in group B (from a score of 4.15 ± 1.68 to 2.89 ± 1.16). Non-regurgitation symptoms (irritability, cough, choking, night-waking) decreased (P = 0.045 at 1 month and 0.017 at 2 months) in group A (from a score of 18 at baseline to 3 after 8 weeks) as compared to group B (from a score of 18 at baseline to 11 after 8 weeks). Weight increased more in group A (29.1 ± 3.9 g/day over 8 weeks) versus group B (23.6 ± 3.5 g/day over 8 weeks) (P < 0.01 at 1 and 2 months) Gastric emptying improved significantly in group A as compared with group B (all P < 0.001 for T1/2, and residual volume at 60 and 90 min). Ingested feeding volume was significantly larger in the group receiving cornstarch-thickened formula, both at 4 weeks (109.4 ± 24.5 vs. 98.5 ± 23.6 mL/meal) (P: 0.042) and at 8 weeks (137.6 ± 27.9 vs. 115.7 ± 26.5 mL/meal) (P < 0.001). Cornstarch-thickened formula feeding decreases the frequency of regurgitation/vomiting, provides better body weight gain and has an accelerated gastric emptying in comparison to a 25% strengthened regular formula in infants with regurgitation. [source] DNA damage in Pakistani pesticide-manufacturing workers assayed using the Comet assayENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 8 2006Javed A. Bhalli Abstract The production and use of chemical pesticides has increased in recent years. Although the increased use of pesticides may benefit agriculture, they are also the potential source of environmental pollution, and exposure to pesticides can have negative consequences for human health. In the present study, we have assessed DNA damage in blood leukocytes from 29 Pakistani pesticide-factory workers and 35 controls of similar age and smoking history. The workers were exposed to various mixtures of organophosphates, carbamates, and pyrethroids. DNA damage was measured with the single cell gel electrophoresis (SCGE) assay or Comet assay, using the mean comet tail length (,m) as the DNA damage metric. Exposed workers had significantly longer comet tail lengths than the controls (mean ± SD 19.98 ± 2.87 vs. 7.38 ± 1.48, P < 0.001). Of the possible confounding factors, smokers had significantly longer mean comet tail lengths than nonsmokers and exsmokers for both the workers (21.48 ± 2.58 vs.18.37 ± 2.28, P < 0.001) and the controls (8.86 ± 0.56 vs. 6.79 ± 1.31, P < 0.001), while age had a minimal effect on DNA damage (P > 0.05 and P < 0.05 for workers and controls, respectively). The results of this study indicate that occupational exposure to pesticides causes DNA damage. Environ. Mol. Mutagen., 2006. © 2006 Wiley-Liss, Inc. [source] Depression and Altered Quality of Life in Women with Epilepsy of Childbearing AgeEPILEPSIA, Issue 1 2004Ettore Beghi Summary: Purpose: To calculate the prevalence of depression in a referral population of women of childbearing age, to define the factors associated with depression, and to assess health-related quality of life (HRQOL) in the same population. Methods: The 642 consecutive women with epilepsy aged 18,55 years were enrolled by 40 neurologists over an 8-month period and asked to give details on selected demographic and clinical features regarding the disease, any associated clinical condition, and any drug treatment. Depression was diagnosed by using the Hamilton depression scale and HRQOL was measured through the SF-36 form. Demographic, clinical, and therapeutic risk factors for depression were searched for within the study population. Results: Depression (any severity) was present at interview in 242 women, giving a prevalence rate of 37.7%[95% confidence interval (CI), 33.9,41.6]. Mild depression was reported by 18.5% of women, moderate depression by 8.6%, major depression by 10.3%, and severe depression by 0.3%. Factors found to be independently associated with depression (any severity) included treatment of associated conditions [relative risk (RR), 1.5; 95% CI, 1.2,1.8), concurrent disability (RR, 1.3; 95% CI, 1.0,1.6), seizures in the preceding 6 months (RR, 1.4; 95% CI, 1.1,1.7), and being unemployed or a housewife (RR, 1.3; 95% CI, 1.0,1.5). Factors associated with moderate to severe depression included treatment for associated conditions (RR, 2.0; 95% CI, 1.4,2.7), seizures in the preceding 6 months (RR, 1.7; 95% CI, 1.2,2.5), and being unemployed or a housewife (RR, 1.6; 95% CI, 1.1,2.2). Compared with normal women of similar age, patients with epilepsy tended to present lower scores for each HRQOL domain (mostly Role Physical, General Health, Social Functioning, and Role Emotional). However, when the analysis was limited to nondepressed women with epilepsy, any difference disappeared. Conclusions: Women with epilepsy of childbearing age are at high risk of depression. Factors associated with depression include lack of occupation, the presence of an underlying disabling condition (with treatment), and the severity of epilepsy. Compared with the general population, depressed women have greater impairment of HRQOL with epilepsy, which reflects the physical, social, and emotional implications of the disease. [source] Components of Relationship Quality in ChimpanzeesETHOLOGY, Issue 9 2008Orlaith N. Fraser A novel approach to studying social relationships in captive adult chimpanzees (Pan troglodytes) was taken by using principal components analysis (PCA) to extract three key components of relationship quality from nine behavioural variables. Based on the loadings of the behavioural variables, the components appeared to match previously hypothesized critical aspects of social relationships and were therefore labelled Value, Compatibility and Security. The effects of kinship, sex combination, age difference and time spent together on each of the relationship quality components were analysed. As expected, kin were found to have more valuable, compatible and secure relationships than non-kin. Female,female dyads were found to be more compatible than male,male or mixed-sex dyads, whereas the latter were found to be most secure. Partners of a similar age were found to have more secure and more valuable relationships than those with a larger age gap. Individuals that were together in the group for longer were more valuable and more compatible, but their relationships were found to be less secure than individuals that were together in the group for a shorter time. Although some of the results may be unexpected based on chimpanzee socio-ecology, they fit well overall with the history and social dynamics of the study group. The methods used confer a significant advantage in producing quantitative composite measures of each component of relationship quality, obtained in an objective manner. These findings therefore promote the use of such measures in future studies requiring an assessment of the qualities of dyadic social relationships. [source] Spatial Association in a Highly Inbred Ungulate Population: Evidence of Fine-Scale Kin RecognitionETHOLOGY, Issue 2 2008Jorge Cassinello We present the first evidence of fine-scale kin recognition, based on a continuous measure of relatedness, in ungulates. The spatial association between herdmates of a captive population of aoudad (Ammotragus lervia), where all the individuals are related, is analysed during resting time. Our goal was to estimate which factors influence individuals' associations. The study population is highly inbred, although it does not show serious deleterious effects caused by consanguinity. It comprises a single captive herd, reproducing freely and in good conditions for more than 10 yr. It emerges that kin, measured as the coefficient of relationship between two given herdmates, is the main factor determining the spatial association (e.g. average distance) of male,male and female,female dyads, as more-related individuals tend to rest closer to each other than less-related ones. As for male,female dyads, individuals of a similar age tend to stay closer. To rule out any familiarity confounding effects, individuals' cohabitation time in the herd was added as a random factor in the analyses. Concerning the type of dyad, mother,calf dyads are characterized by higher proximity than others, particularly during the suckling period, whereas males tend to stay closer to each other than females or male,female dyads, being also more kin-related. Female social rank does not influence spatial association between herdmates. These results are related to group composition of the species in the wild, which are characterized by intense mother,calf bonds and all-male groups that are probably kin-related. It is seen that adult male,female associations are not related to kinship, but to age similarity, which is in accord with the assumption that main family groups in the wild are formed by matrilineal lines, whereas males are the dispersing sex. [source] Lactating Females Do Not Discriminate Between Their Own Young and Unrelated Pups in the Communally Breeding Rodent, Octodon degusETHOLOGY, Issue 9 2006Luis A. Ebensperger Females in numerous rodent species engage in communal nesting and breeding, in which they share one or more nests to rear their young. A potential cost of communal nesting and breeding is that mothers divert resources to unrelated offspring. One way mothers could avoid this cost is to recognize and favour their own young over unrelated offspring when allocating maternal effort. We assessed whether female degus (Octodon degus), a communally nesting and breeding caviomorph rodent, discriminate between their own and unrelated offspring during lactation. Female degus previously have been shown to distinguish between their own and unrelated pups when exposed to odours from both. We measured pup discrimination based on differences in the retrieval behaviour of females that were in early or intermediate lactation directed towards their own and unrelated offspring; offspring presented were of similar or different age. Before any event of pup retrieval, lactating females spent similar amounts of time and interacted to a similar extent with their own and unrelated pups. During pup retrieval, all lactating females transported both pups to the nest. Neither relatedness to pups, nor pup-age differences, influenced the order in which pups were retrieved to the nest. Dams waited similar amounts of time before retrieving the first pup when the first transported young was their own or unrelated. Likewise, females waited similar amounts of time before retrieving the second pup when the pup transported first was their own or unrelated. The time between first and second pup transport events was longer when dams were in early when compared with intermediate lactation, but only when pups were of similar age. All experimental subjects nursed unrelated pups after they were retrieved. Collectively, our results do not support the hypothesis that communally breeding female degus use their recognition ability to discriminate against unrelated offspring in favour of their own young. [source] Long-term effects of chemotherapy on orodental structures in children with non-Hodgkin's lymphomaEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2004Aynur O The aim of this study was to investigate the late effects of treatment for childhood non-Hodgkin's lymphomas (NHL) on oral health and dental development. Thirty-six long-term survivors that had been treated with chemotherapy of childhood NHL were included in this study and 36 volunteers with similar age and sex distribution served as controls. Both groups underwent a complete orodental examination for decayed, missing and filled teeth and surfaces, gingival and periodontal health according to the Loe,Silness Gingival Index and Sillnes,Loe Plaque Index, enamel defects and discolorations, root malformations, eruption status, agenesis, premature apexifications and microdontia. The severity of these disturbances related to age at the time of NHL diagnosis were also evaluated by creating two groups as <,5 yr and >,5 yr. Although none of the parameters altered with age, patients had significantly higher plaque index, more enamel discolorations and root malformations than did the controls. The results show that long-term survivors of NHL patients exhibit some orodental disturbances that may be attributed to the chemotherapy regimens. [source] Attitudes to dental care among parents of uncooperative vs. cooperative child dental patientsEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2002Kristina Arnrup The aim of this cross-sectional questionnaire study was to investigate four aspects of parents' attitudes to dental care (knowledge, child's oral health behavior, priorities and responsibility). One study group (n=50) of parents of uncooperative child dental patients (aged 8,12 yr) was compared to a reference group (n=113) of parents of ordinary child dental patients of similar age, and to a second study group (n=36) of parents of uncooperative younger child patients (aged 4,7 yr). Study group parents had significantly lower socio-economic status and a higher level of dental fear as compared to parents of ordinary child patients. We found indications of a poorer dental knowledge and a differing responsibility-taking profile among study group parents. Their children also had sweets more often. As compared to parents of younger children, the older study group parents had lower socio-economic status and showed a lower responsibility-taking related to the child's treatment refusal. In conclusion, parents of uncooperative children differ from parents of ordinary child dental patients, not only in socio-economic status and dental fear, but also in aspects such as dental knowledge and responsibility-taking. These differences were partly related to the child's age. [source] Physical apertures as constraints on egg size and shape in the Common Musk Turtle, Sternotherus odoratusFUNCTIONAL ECOLOGY, Issue 1 2001P. J. Clark Summary 1,Egg size in turtles often increases with female size, contrary to expectations of optimality. Functional constraints on egg width imposed by the pelvic aperture or the gap between the carapace and plastron (the caudal gap) have been inferred for a few populations but appear inapplicable in others. 2,For Sternotherus odoratus (the Common Musk Turtle), the pelvic aperture was always wider than the width of the female's largest egg by at least 3·7 mm. The caudal gap was narrower than the widest egg for 25·7% of the females. 3,Egg width increased, and elongation (length/width) decreased, as female size and clutch size increased. 4,Females at three ecologically contrasting sites differed appreciably in size but produced eggs of the same mean shape and size, despite the strong within-site changes in both egg size and shape with female size. As the younger females at all sites were of similar age and produced eggs of similar size and shape (again, despite differences in body size), egg size and shape may be age-specific. 5,No optimal egg size prevailed but the scaled residuals of egg size with female mass were less variable than were those for clutch size. [source] The surface archaeological record in arid Australia: Geomorphic controls on preservation, exposure, and visibilityGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 2 2009Patricia C. Fanning The conventional approach to assessing the archaeological record in most parts of the world involves a combination of excavation of stratified deposits and extensive survey of surface deposits. Although widely applied in Australia, in both research-based and management archaeology, the method does not conform well to the nature of the surface archaeological record here. Over much of semi-arid and arid Australia, archaeological "sites" are, in fact, accretion phenomena that are not easily interpreted as the outcome of short-term behavioral events. Using results from twelve years of geoarchaeological research in western New South Wales, we demonstrate that there is considerable variability in landsurface age, and hence the "availability" of archaeological surfaces, over relatively short distances. Therefore, it cannot be assumed that stone artifact deposits, for example, that appear to be similar in character are of similar age. Data are also presented that demonstrate that the presence of artifacts on the surface, their apparent absence in sediments buried beneath the surface, and the apparent recent ubiquity of the archaeological record are all a function of geomorphic processes that, at the same time, expose some artifact deposits at the surface and erode and bury others amid large volumes of sediment. Interpreting the surface artifact record within a spatial and temporal geomorphic framework is crucial to understanding the past human behavior that the artifact deposits represent. © 2009 Wiley Periodicals, Inc. [source] Regional teleseismic tomography of the western Lachlan Orogen and the Newer Volcanic Province, southeast AustraliaGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 2 2002Frank M. Graeber Summary From 1998 May to September a portable array of 40 short-period digital seismograph stations was operated in western Victoria, southeast Australia, across the western end of the mid-Paleozoic Lachlan Foldbelt and the Newer Volcanic Province. Consisting of four parallel, almost W,E-oriented receiver lines, the array covered an area of about 270 × 150 km2. The major aim of the LF98 (Lachlan Foldbelt survey 1998) project is to map lateral variations in P -wave speeds (Vp) in the crust and upper mantle using teleseismic arrival time tomography, primarily in order to investigate whether the major surface structural zones are associated with seismic velocity signatures at depth. Little a priori information from seismic profiling is available. We invert 4067 relative arrival time residuals for a minimum structure Vp model in the upper few hundred km using non-linear iteration and 3-D ray tracing. The most prominent negative anomaly (,3.8 per cent) in Vp is found at a depth of about 45 km underneath the eastern part of the Newer Volcanic Province. It correlates spatially with the highest density of Pliocene and Pleistocene eruption centres northwest of Melbourne, and is therefore interpreted as a hotspot-related high-temperature anomaly causing reduced mantle velocities. The related coherent volume of significantly lower than average velocities extends down to depths greater than 100 km in the east, and extends west underneath the Newer Volcanic Province. A strong velocity contrast, with average velocities ,2 per cent greater in the west, is found down to about 100 km across the Moyston Fault Zone, which forms the major structural boundary between the early-Paleozoic Delamerian Orogen in the west and the Lachlan Orogen in the east. This result suggests that the Moyston Fault Zone should be seen as a major lithospheric boundary. In the south this boundary is also expressed by a distinct discontinuity in Sr-isotopic ratios of xenoliths (the so-called Mortlake discontinuity) and a change in the geochemistry of plutons of similar age. However, if the east to west velocity contrast originally existed in this southern zone, it is now overprinted by the thermally reduced mantle velocities beneath the Newer Volcanic Province. [source] A precisely dated Proterozoic palaeomagnetic pole from the North China craton, and its relevance to palaeocontinental reconstructionGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 1 2000Henry C. Halls A palaeomagnetic pole position, derived from a precisely dated primary remanence, with minimal uncertainties due to secular variation and structural correction, has been obtained for China's largest dyke swarm, which trends for about 1000 km in a NNW direction across the North China craton. Positive palaeomagnetic contact tests on two dykes signify that the remanent magnetization is primary and formed during initial cooling of the intrusions. The age of one of these dykes, based on U,Pb dating of primary zircon, is 1769.1 ± 2.5 Ma. The mean palaeomagnetic direction for 19 dykes, after structural correction, is D = 36°, I = , 5°, k = 63, ,95 = 4°, yielding a palaeomagnetic pole at Plat=36°N, Plong=247°E, dp = 2°, dm = 4° and a palaeolatitude of 2.6°S. Comparison of this pole position with others of similar age from the Canadian Shield allows a continental reconstruction that is compatible with a more or less unchanged configuration of Laurentia, Siberia and the North China craton since about 1800 Ma [source] Bone properties and muscle strength of young haemophilia patientsHAEMOPHILIA, Issue 4 2005B. Falk Summary., Purpose:, To evaluate bone properties, muscle strength and the relationship between the two, in young (7.0,17.7 years) haemophilia patients (h) and healthy boys (c). Subjects:, Twenty-seven boys with severe haemophilia and 33 healthy boys, of similar age, body mass, height, (mean ± sd for h and c, respectively: 11.2 ± 3.2 vs. 11.4 ± 2.9 years, 42.6 ± 16.6 vs. 41.6 ± 17.3 kg, 145 ± 18 vs. 146 ± 17 cm) and pubertal stage according to secondary sex characteristics, volunteered for the study. all subjects were physically inactive (as determined by questionnaire). Methods:, Subjects performed isokinetic elbow and knee extension and flexion tests at two angular velocities (biodex system ii dynamometer). Bone properties were evaluated by qualitative ultrasound (sunlight omnisenseTM), at the distal radius and tibial mid-shaft. H subjects received prophylactic factor viii treatment within the 24 h preceding testing. No test was performed in the presence of haemorrhage. Results:, Muscle strength was consistently higher in c compared with h, especially in the lower limbs (e.g. knee extension: 1.80 ± 0.44 vs 1.48 ± 0.53 N·m·kg,1 body mass, respectively, p = 0.01). No differences were observed in tibial or radial speed of sound between groups. Correlations between muscle strength and bone properties were observed only in the lower limbs and only in c (r = 0.37,0.48). Conclusion:, Muscle strength, especially lower limbs' strength, was lower in haemophilia patients compared with a matched, similarly inactive population of healthy boys. Nevertheless, at this age range, this relative weakness is not associated with inferior bone properties. [source] Intrahepatic hepatitis C viral RNA status of serum polymerase chain reaction,negative individuals with histological changes on liver biopsyHEPATOLOGY, Issue 6 2001Sharon Barrett For individuals testing anti-HCV positive but negative for HCV RNA in serum, diagnosis remains unclear. Debate exists over whether these individuals have resolved infection or have similar clinical, histological, and virological profiles as serum PCR,positive individuals. The aim of this study was to assess the significance of histological changes in the liver of 33 serum PCR,negative women by investigation of clinical, histological, and intrahepatic HCV RNA status. For comparison, clinical and histological data from 100 serum PCR,positive women is presented. Viral RNA status was determined in snap-frozen liver biopsies using a sensitive nested PCR with an internal control. Although serum PCR,positive and ,negative individuals shared similar age at diagnosis, source, and duration of infection, they differed from a clinical, histological, and virological perspective. Mean serum ALT levels were significantly lower in serum PCR,negative women (27.4 IU/L ± 18 vs. 58.7 IU/L ± 40 P < .001). Similarly, although inflammation (82%) and mild fibrosis (15%) were observed in PCR,negative biopsies, the mean HAI/fibrosis scores were significantly lower than in serum PCR,positive biopsies (1.9 ± 1.5/0.15 ± 0.4 vs. 4.2 ± 1.4/1.1 ± 1.3, respectively). Finally, HCV RNA was not detectable in serum PCR,negative liver biopsies but was detectable in all serum PCR,positive control biopsies. In conclusion, serum PCR,negative individuals may have mild histological abnormalities more suggestive of nonspecific reactive changes, steatosis or nonalcoholic steatohepatitis rather than chronic HCV, even when significant antibody responses are present in serum. Negative serum PCR status appears to reflect cleared past-exposure in liver. [source] Tamoxifen and contralateral breast cancer in BRCA1 and BRCA2 carriers: An updateINTERNATIONAL JOURNAL OF CANCER, Issue 9 2006Jacek Gronwald Abstract Women with a mutation in BRCA1 or BRCA2 face a lifetime risk of breast cancer of ,80%, and following the first diagnosis the10-year risk of contralateral breast cancer is ,30%. It has been shown that both tamoxifen and oophorectomy prevent contralateral breast cancer, but it is not clear whether there is a benefit in giving tamoxifen to women who have previously undergone an oophorectomy. Furthermore, the relative degree of protection in BRCA1 and BRCA2 carriers has not been well evaluated. We studied 285 women with bilateral breast cancer and a BRCA1 or BRCA2 mutation, and 751 control women with unilateral breast cancer and a BRCA1 or BRCA2 mutation in a matched case-control study. Control women were of similar age and had a similar age of diagnosis of breast cancer and had been followed for as long as the case for a second primary breast cancer. The history of tamoxifen use for treating the first breast cancer was compared between bilateral and unilateral cases. The multivariate odds ratio for contralateral breast cancer associated with tamoxifen use was 0.50 for carriers of BRCA1 mutations (95% CI, 0.30,0.85) and was 0.42 for carriers of BRCA2 mutations (95% CI, 0.17,1.02). The protective effect of tamoxifen was not seen among women who had undergone an oophorectomy (OR = 0.83; 95%CI, 0.24,2.89) but this subgroup was small. In contrast, a strong protective effect of tamoxifen was apparent among women who were premenopausal or who had undergone natural menopause (OR = 0.44; 95% CI, 0.27,0.65). © 2005 Wiley-Liss, Inc. [source] Does education moderate neuropsychological impairment in late-life depression?INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 5 2005Rishi K. Bhalla Abstract Objective The increased resistance of better-educated individuals to the cognitive effects of neuropathology has been conceptualized as reflecting brain reserve. This study examined whether educational level influences the degree of neuropsychological impairment associated with late-life depression. Methods The neuropsychological performances of 115 older depressed patients and of 44 comparison subjects of similar age and education were compared as a function of educational level. Results While depressed patients performed worse than comparison subjects on all the measures, the severity of this impairment (with respect to comparison subjects) did not differ with the educational level of the patients. Conclusions Brain reserve, as indexed by the patients' level of education, does not mitigate the cognitive decrements associated with late-life depression. Copyright © 2005 John Wiley & Sons, Ltd. [source] Comparison of ventilator-dependent child reports of health-related quality of life with parent reports and normative populationsJOURNAL OF ADVANCED NURSING, Issue 1 2007Jane Noyes Abstract Title. Comparison of ventilator-dependent child reports of health-related quality of life with parent reports and normative populations Aims., This paper is a report of the first study of ventilator-dependent child and parent ratings of health-related quality of life using a validated instrument, which was undertaken as part of a case study of costs and consequences. Background., Advances in medical care and technologies such as the ventilator have extended childhood illness trajectories beyond our current range of knowledge and experience. These advances and their effects reinforce the need for further research to determine health-related quality of life as an outcome of ventilator-dependency in childhood. Methods., The KINDL was administered to ventilator-dependent children aged 4,18 years and parents as part of an in-depth case study. Twenty-seven parents and 17 children (including 17 child-parent pairs) completed questionnaires. Data were collected between 2001 and 2004. Findings were compared with normative values derived from a representative sample of children of a similar age in the general population. Results., Ventilator-dependent children reported significantly lower overall health-related quality of life, and significantly lower scores on all domains except about their friends, compared with school children, and chronically ill children in respect of their disease. Parents and children rated children's overall health-related quality of life the same but parents reported significantly lower scores for their child's disease and relationships with friends. There was a positive correlation between children and parents in all areas apart from self-esteem and school. Conclusions., Both child and parent perspectives are needed to understand the impact of ventilator-dependency and associated co-morbidity on the child. As new interventions and models of service delivery emerge it will be important for nurses to understand the impact on the child by evaluating physical, emotional and social consequences. [source] Childhood Fractures Are Associated With Decreased Bone Mass Gain During Puberty: An Early Marker of Persistent Bone Fragility?,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2006Serge L Ferrari MD Abstract Whether peak bone mass is low among children with fractures remains uncertain. In a cohort of 125 girls followed over 8.5 years, 42 subjects reported 58 fractures. Among those, BMC gain at multiple sites and vertebral bone size at pubertal maturity were significantly decreased. Hence, childhood fractures may be markers of low peak bone mass acquisition and persistent skeletal fragility. Introduction: Fractures in childhood may result from a deficit in bone mass accrual during rapid longitudinal growth. Whether low bone mass persists beyond this period however remains unknown. Materials and Methods: BMC at the spine, radius, hip, and femur diaphysis was prospectively measured over 8.5 years in 125 girls using DXA. Differences in bone mass and size between girls with and without fractures were analyzed using nonparametric tests. The contribution of genetic factors was evaluated by mother-daughter correlations and that of calcium intake by Cox proportional hazard models. Results: Fifty-eight fractures occurred in 42 among 125 girls (cumulative incidence, 46.4%), one-half of all fractures affecting the forearm and wrist. Girls with and without fractures had similar age, height, weight. and calcium intake at all time-points. Before and during early puberty, BMC and width of the radius diaphysis was lower in the fracture compared with no-fracture group (p < 0.05), whereas aBMD and BMAD were similar in the two groups. At pubertal maturity (Tanner's stage 5, mean age ± SD, 16.4 ± 0.5 years), BMC at the ultradistal radius (UD Rad.), femur trochanter, and lumbar spine (LS), and LS projected bone area were all significantly lower in girls with fractures. Throughout puberty, BMC gain at these sites was also decreased in the fracture group (LS, ,8.0%, p = 0.015; UD Rad., ,12.0%, p = 0.004; trochanter, ,8.4%, p = 0.05 versus no fractures). BMC was highly correlated between prepuberty and pubertal maturity (R = 0.54,0.81) and between mature daughters and their mothers (R = 0.32,0.46). Calcium intake was not related to fracture risk. Conclusions: Girls with fractures have decreased bone mass gain in the axial and appendicular skeleton and reduced vertebral bone size when reaching pubertal maturity. Taken together with the evidence of tracking and heritability for BMC, these observations indicate that childhood fractures may be markers for low peak bone mass and persistent bone fragility. [source] Differential rates of morphological divergence in birdsJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 5 2004F. Bokma Abstract There are more small-bodied bird species than there are large-bodied, even on a logarithmic scale. In birds this pattern, which is also found in other higher taxa, appears not to be due to neutral evolution. It has often been suggested that the skew of body size frequency distributions is the result of a relationship between body size and the net rate of speciation, but phylogenetic analyses so far have rejected the hypothesis that small-bodied species are subject to higher net rates of speciation. On the contrary, we show that there exists a relationship between body size and its own evolutionary variability: avian families of small body size show less interspecific variation in body size than large-bodied families of similar age and species richness. [source] Specificity of muscle action after anterior cruciate ligament injuryJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 6 2003Glenn N. Williams Abstract Neuromuscular control is believed to be a critical factor in dynamic knee stability. The purpose of this study was to evaluate voluntary muscle control in anterior cruciate ligament deficient (ACL-D) and uninjured people. Twenty athletes of similar age participated in this study. Subjects performed a target-matching protocol that required them to produce isometric moments about the knee with fine control in flexion, extension, varus, and valgus (i.e., loads were generated in the plane perpendicular to the long axis of the shank). Electromyographic data were collected from 10 muscles that span the knee. A specificity index was calculated for each muscle to describe how fine-tuned (specific) its muscle activity pattern was with respect to its principal direction of action in the load plane. Diminished specificity of muscle action was observed in 8 of 10 muscles in the ACL-D subjects' involved knees when compared with the activity patterns from their uninvolved knees and those from the uninjured subjects' knees. The vastus lateralis muscle was especially affected. Increased and more global co-contraction was also observed in the ACL-D limbs. The alterations in muscle firing patterns observed in this study are consistent with diminished neuromuscular control. © 2003 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] OIL-PRONE LOWER CARBONIFEROUS COALS IN THE NORWEGIAN BARENTS SEA: IMPLICATIONS FOR A PALAEOZOIC PETROLEUM SYSTEMJOURNAL OF PETROLEUM GEOLOGY, Issue 2 2010J.H. Van Koeverden In this study, we assess the oil generation potential of Lower Carboniferous, liptinite-rich coals in the Tettegras Formation on the Finnmark Platform, southern Norwegian Barents Sea. Oil from these coals has been expelled into intercalated sandstones. The coals may have contributed to petroleum recorded in well 7128/4,1 on the Finnmark Platform and may constitute a new Palaeozoic source rock in the Barents Sea. The Tettegras Formation coals contain up to 80 vol.% liptinite (mineral matter free base) and have low oxygen indices. Hydrogen indices up to 367 mg HC/g TOC indicate liquid hydrocarbon potential. In wells 7128/4,1 and 7128/6,1, the coals have vitrinite reflectance Ro= 0.75,0.85 %. Compared to shale and carbonate source rocks, expulsion from coal in general begins at higher maturities (Ro= 0.8,0.9% and Tmax= 444,453°C). Thus, the coals in the wells are mostly immature with regard to oil expulsion. The oil in well 7128/4,1 most likely originates from a more mature part of the Tettegras Formation in the deeper northern part of the Finnmark Platform. Wide variations in biomarker facies parameters and ,13C isotope values indicate a heterogeneous paralic depositional setting. The preferential retention by coal strata of naphthenes (e.g. terpanes and steranes) and aromatic compounds, compared to n-alkanes and acyclic isoprenoids, results in a terrigenous and waxy oil. This oil however contains marine biomarkers derived from the intercalated shales and siltstones. It is therefore important to consider the entire coal-bearing sequence, including the intercalated shales, in terms of source rock potential. Coals of similar age occur on Svalbard and Bjørnøya. The results of this study therefore suggest that a Lower Carboniferous coaly source rock may extend over large areas of the Norwegian Barents Sea. This source rock is mature in areas where the otherwise prolific Upper Jurassic marine shales are either immature or missing and may constitute a new Palaeozoic coal-sourced petroleum system in the Barents Sea. [source] Effects of Abstinence From Alcohol on the Broad Phospholipid Signal in Human Brain: An In Vivo 31P Magnetic Resonance Spectroscopy StudyALCOHOLISM, Issue 8 2001M. R. Estilaei Background: In vivo phosphorus magnetic resonance spectroscopy (31P MRS) at a magnetic field strength of 1.5 T allows measurement of fairly mobile membrane phospholipids in the human brain. We previously showed that subjects who are heavy drinkers had a smaller signal and a shorter transverse relaxation time (T2) of white matter phospholipids than light drinkers, which suggested lower concentrations and molecular mobility of phospholipids in heavy drinkers. The purpose of the present study was to measure if such chronic alcohol-induced white matter tissue changes are persistent in long-term abstinent alcoholics. Methods: Fourteen abstinent alcoholics (mean age 45 years, seven men and seven women) were studied by localized 31P MRS in the centrum semiovale and were compared with 13 male, alcohol-dependent, heavy drinkers and 23 nondependent light drinkers (17 men, 6 women) of similar age. Methods for measurements of the broad membrane phospholipid signal and its relaxation time were described previously. Results: Phospholipid concentrations and relaxation times in alcoholics abstinent for an average of 31 months were not significantly different from those measured in light drinkers. The contribution of fast and slowly relaxing signal components to the broad phospholipid signal, however, was still different in abstinent alcoholics compared with light drinkers. No effects of sex or of family history of alcoholism were noted on any of our spectroscopic measures within the light-drinking or abstinent groups. Conclusions: Most of our results suggest at least partial recovery of chronic alcohol-induced white matter phospholipid damage with long-term abstinence. They offer myelination changes and/or dendritic rearborization as a possible mechanism for the commonly observed white matter volume gain with prolonged abstinence. But the results also suggest a persistent abnormality in the nature and/or physical properties of white matter phospholipids in long-term abstinent alcoholics. [source] Economic evaluation and 1-year survival analysis of MARS in patients with alcoholic liver diseaseLIVER INTERNATIONAL, Issue 2003Franz P. Hessel Abstract Objective of this study was to determine 1-year survival, costs and cost-effectiveness of the artificial liver support system Molecular Adsorbent Recirculating System (MARS) in patients with acute-on-chronic liver failure (ACLF) and an underlying alcoholic liver disease. In a case,control study, 13 patients treated with MARS were compared to 23 controls of similar age, sex and severity of disease. Inpatient hospital costs data were extracted from patients' files and hospital's internal costing. Patients and treating GPs were contacted, thus determining resource use and survival 1-year after treatment. Mean 1-year survival time in MARS group was 261 days and 148 days in controls. Kaplan,Meier analysis shows advantages of MARS patients (Logrank: P = 0.057). Direct medical costs per patient for initial hospital stay and 1-year follow-up from a payer's perspective were ,18 792 for MARS patients and ,9638 for controls. The costs per life-year gained are ,29 719 (time horizon 1 year). From a societal perspective, the numbers are higher (costs per life-year gained: ,79 075), mainly because of the fact that there is no regular reimbursement of MARS and therefore intervention costs were not calculated from payer's perspective. A trade-off between medical benefit and higher costs has to be made, but 1-year results suggest an acceptable cost-effectiveness of MARS. Prolonging the time horizon and including indirect costs, which will be done in future research, would probably improve cost-effectiveness. [source] Ascites after liver transplantation,A mysteryLIVER TRANSPLANTATION, Issue 5 2004Charmaine A. Stewart Ascites after liver transplantation, although uncommon, presents a serious clinical dilemma. The hemodynamic changes that support the development of ascites before liver transplantation are resolved after transplant; therefore, persistent ascites (PA) after liver transplantation is unexpected and poorly characterized. The aim of this study was to define the clinical factors associated with PA after liver transplantation. This was a retrospective case,control analysis of patients who underwent liver transplantation at the University of Pennsylvania. PA occurring for more than 3 months after liver transplantation was confirmed by imaging studies. PA was correlated with multiple recipient and donor variables, including etiology of liver disease, preoperative ascites, prior portosystemic shunt (PS), donor age, and cold ischemic (CI) time. There were 2 groups: group 1, cases with PA transplanted from November 1990 to July 2001, and group 2, consecutive, control subjects who underwent liver transplantation between September 1999 and December 2001. Both groups were followed to censoring, May 2002, or death. Twenty-five from group 1 had ascites after liver transplantation after a median follow-up of 2.6 years. In group 1 vs group 2 (n = 106), there was a male predominance 80% vs 61% (P = .10) with similar age 52 years; chronic hepatitis C virus (HCV) was diagnosed in 88% vs 44% (P < .0001); preoperative ascites and ascites refractory to treatment were more prevalent in group 1 (P = .0004 and P =.02, respectively), and CI was higher in group 1, (8.5 hours vs 6.3 hours, P = .002). Eight of the 25 (group 1) had portal hypertension with median portosystemic gradient 16.5 mm Hg (range, 16,24). PS was performed in 7 of 25 cases, which resulted in partial resolution of ascites. The development of PA after liver transplantation is multifactorial; HCV, refractory ascites before liver transplantation, and prolonged CI contribute to PA after liver transplantation. (Liver Transpl 2004;10:654,660.) [source] Petrography, geochemistry, and alteration of country rocks from the Bosumtwi impact structure, GhanaMETEORITICS & PLANETARY SCIENCE, Issue 4-5 2007Forson KARIKARI The country rocks, mainly meta-graywacke, shale, and phyllite of the Early Proterozoic Birimian Supergroup and some granites of similar age, are characterized by two generations of alteration. A pre-impact hydrothermal alteration, often along shear zones, is characterized by new growth of secondary minerals, such as chlorite, sericite, sulfides, and quartz, or replacement of some primary minerals, such as plagioclase and biotite, by secondary sericite and chlorite. A late, argillic alteration, mostly associated with the suevites, is characterized by alteration of the melt/glass clasts in the groundmass of suevites to phyllosilicates. Suevite, which occurs in restricted locations to the north and to the south-southwest of the crater rim, contains melt fragments, diaplectic quartz glass, ballen quartz, and clasts derived from the full variety of target rocks. No planar deformation features (PDFs) in quartz were found in the country rock samples, and only a few quartz grains in the suevite samples show PDFs, and in rare cases two sets of PDFs. Based on a total alkali element-silica (TAS) plot, the Bosumtwi granites have tonalitic to quartz-dioritic compositions. The Nb versus Y and Ta versus Yb discrimination plots show that these granites are of volcanic-arc tectonic provenance. Provenance studies of the metasedimentary rocks at the Bosumtwi crater have also indicated that the metasediments are volcanic-arc related. Compared to the average siderophile element contents of the upper continental crust, both country rocks and impact breccias of the Bosumtwi structure show elevated siderophile element contents. This, however, does not indicate the presence of an extraterrestrial component in Bosumtwi suevite, because the Birimian country rocks also have elevated siderophile element contents, which is thought to result from regional hydrothermal alteration that is also related to widespread sulfide and gold mineralization. [source] Mass segregation in young compact clusters in the Large Magellanic Cloud , III.MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2002Implications for the initial mass function ABSTRACT The distribution of core radii of rich clusters in the Large Magellanic Cloud (LMC) systematically increases in both upper limit and spread with increasing cluster age. Cluster-to-cluster variations in the stellar initial mass function (IMF) have been suggested as an explanation. We discuss the implications of the observed degree of mass segregation in our sample clusters for the shape of the initial mass function. Our results are based on Hubble Space Telescope/WFPC2 observations of six rich star clusters in the LMC, selected to include three pairs of clusters of similar age, metallicity and distance from the LMC centre, and exhibiting a large spread in core radii between the clusters in each pair. All clusters show clear evidence of mass segregation: (i) their luminosity function slopes steepen with increasing cluster radius, and (ii) the brighter stars are characterized by smaller core radii. For all sample clusters, both the slope of the luminosity function in the cluster centres and the degree of mass segregation are similar to each other, within observational errors of a few tenths of power-law slope fits to the data. This implies that their initial mass functions must have been very similar, down to ,0.8,1.0 M,. We therefore rule out variations in the IMF of the individual sample clusters as the main driver of the increasing spread of cluster core radii with cluster age. [source] Setting new constraints on the age of the UniverseMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2001Ignacio Ferreras There are three independent techniques for determining the age of the Universe: via cosmochronology of long-lived radioactive nuclei, via stellar modelling and population synthesis of the oldest stellar populations, and, most recently, via the precision cosmology that has become feasible with the mapping of the acoustic peaks in the cosmic microwave background. We demonstrate that all three methods give completely consistent results, and enable us to set rigorous bounds on the maximum and minimum ages that are allowed for the Universe. We present new constraints on the age of the Universe by performing a multiband colour analysis of bright cluster ellipticals over a large redshift range , which allows us to infer the ages of their stellar populations over a wide range of possible formation redshifts and metallicities. Applying a prior to Hubble's constant of we find the age of the Universe to be (1,), in agreement with the estimates from Type Ia supernovae, as well as with the latest uranium decay estimates, which yield an age for the Milky Way of . If we combine the results from cluster ellipticals with the analysis of the angular power spectrum of the cosmic microwave background and with the observations of Type Ia supernovae at high redshift, we find a similar age: . Without the assumption of any priors, universes older than 18 Gyr are ruled out by the data at the 90 per cent confidence level. [source] The 6-minute walk test as a new outcome measure in Duchenne muscular dystrophyMUSCLE AND NERVE, Issue 4 2010Craig M. McDonald MD Abstract Walking abnormalities are prominent in Duchenne muscular dystrophy (DMD). We modified the 6-minute walk test (6MWT) for use as an outcome measure in patients with DMD and evaluated its performance in 21 ambulatory boys with DMD and 34 healthy boys, ages 4 to 12 years. Boys with DMD were tested twice, ,1 week apart; controls were tested once. The groups had similar age, height, and weight. All tests were completed. Boys who fell recovered rapidly from falls without injury. Mean ± SD [range] 6-minute walk distance (6MWD) was lower in boys with DMD than in controls (366 ± 83 [125,481] m vs. 621 ± 68 [479,754] m; P < 0.0001; unpaired t -test). Test-retest correlation for boys with DMD was high (r = 0.91). Stride length (R2 = 0.89; P < 0.0001) was the major determinant of 6MWD for both boys with DMD and controls. A modified 6MWT is feasible and safe, documents disease-related limitations on ambulation, is reproducible, and offers a new outcome measure for DMD natural history and therapeutic trials. Muscle Nerve, 2010 [source] Cognitive dysfunction 1,2 years after non-cardiac surgery in the elderlyACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 10 2000H. Abildstrom Background: Postoperative cognitive dysfunction (POCD) is a well-recognised complication of cardiac surgery, but evidence of POCD after general surgery has been lacking. We recently showed that POCD was present in 9.9% of elderly patients 3 months after major non-cardiac surgery. The aim of the present study was to investigate whether POCD persists for 1,2 years after operation. Methods: A total of 336 elderly patients (median age 69 years, range 60,86) was studied after major surgery under general anesthesia. Psychometric testing was performed before surgery and at a median of 7, 98 and 532 days postoperatively using a neuropsychological test battery with 7 subtests. A control group of 47 non-hospitalised volunteers of similar age were tested with the test battery at the same intervals. Results: 1,2 years after surgery, 35 out of 336 patients (10.4%, CI: 7.2,13.7%) had cognitive dysfunction. Three patients had POCD at all three postoperative test sessions (0.9%). From our definition of POCD, there is only a 1:64 000 likelihood that a single subject would have POCD at all three test points by chance. Logistic regression analysis identified age, early POCD, and infection within the first three postoperative months as significant risk factors for long-term cognitive dysfunction. Five of 47 normal controls fulfilled the criteria for cognitive dysfunction 1,2 years after initial testing (10.6%, CI: 1.8,19.4%), i.e. a similar incidence of age-related cognitive impairment as among patients. Conclusion: POCD is a reversible condition in the majority of cases but may persist in approximately 1% of patients. [source] | ||||||||||||||||||||||||||||||||||||||||