bluuebunny/crossref_metadata_2025_split huggingface dataset:
Geographic variation in density‐dependent dynamics impacts the synchronizing effect of dispersal and regional stochasticity
Authors: Liebhold Andrew M. , Johnson Derek M. , Bjørnstad Ottar N. 
Published: January 2006

AbstractExplanations for the ubiquitous presence of spatially synchronous population dynamics have assumed that density‐dependent processes governing the dynamics of local populations are identical among disjunct populations, and low levels of dispersal or small amounts of regionalized stochasticity (“Moran effect”) can act to synchronize populations. In this study we used historical spatially referenced data on gypsy moth (Lymantria dispar) outbreaks to document that density‐dependent processes can vary substantially across geographical landscapes. This variation may be due in part to geographical variation in habitat (e.g., variation in forest composition). We then used a second‐order log‐linear stochastic model to explore how inter‐population variation in density‐dependent processes affects synchronization via either synchronous stochastic forcing or dispersal. We found that geographical variation in direct density‐dependence (first order) greatly diminishes synchrony caused by stochasticity but only slightly decreases synchronization via dispersal. Variation in delayed density‐dependence (second order) diluted synchrony caused by regional stochasticity to a lesser extent than first‐order variation, but it did not have any influence on synchrony caused by dispersal. In general, synchronization caused by dispersal was primarily dependent upon the instability of populations and only weakly, if at all, affected by similarities in density‐dependence among populations. We conclude that studies of synchrony should carefully consider both the nature of the synchronizing agents and the pattern of local density‐dependent processes, including how these vary geographically.
Community structure and stability analysis for intraguild interactions among host, parasitoid, and predator
Authors: Nakazawa T , Yamamura N 
Published: January 2006

AbstractIntraguild predation (IGP) occurs when one species preys on a competitor species that shares a common resource. Modifying a prey–predator model with prey infection, we propose a model of IG interactions among host, parasitoid, and predator, in which the predator eats parasitized and unparasitized hosts, and the adult parasitoid density is explicitly expressed. Parameter dependences of community structure, including stability of the system, were analytically obtained. Depending on interaction strength (parasitization and predation on unparasitized and parasitized hosts), the model provides six types of community structure: (1) only the host exists, (2) the host and predator coexist stably, (3) the host and parasitoid coexist stably, (4) the host–parasitoid population dynamics are unstable, (5) the three species coexist stably, and (6) the population dynamics of the three species are unstable. In contrast to a traditional prey–predator model with prey infection, which predicts that population dynamics are always locally stable, our model predicts that they are unstable when the parasitization rate is high.
Mucopolysaccharidosis type VI: Identification of novel mutations on the arylsulphatase B gene in South American patients
Authors: Petry M. F. G. , Nonemacher K. , Sebben J. C. , Schwartz I. V. D. , Azevedo A. C. M. , Burin M. G. , De Rezende A. R. , Kim C. A. , Giugliani R. , Leistner‐Segal S. 
Published: January 2006

SummaryMucopolysaccharidosis type VI (Maroteaux–Lamy syndrome, MPS VI) is an autosomal recessive disorder caused by deficiency of N‐acetylgalactosamine‐4‐sulphatase (ARSB),which leads to the lysosomal accumulation and excretion of dermatan sulphate (DS). In this study, 13 unrelated MPS VI patients (12 Brazilian and 1 Chilean) were investigated regarding the identification of the ARSB gene mutations using PCR, SSCP and sequencing. The exons with altered mobility on SSCP were sequenced, as well as all the exons of patients with no SSCP alteration. Seven novel mutations were identified: D59N, L72R, Q88H, P93S, R197X, 1279delA and c.1143−8T > G. The previously reported mutations 1533del23, R315Q and 427delG were found in six, three and two alleles respectively. The other mutations already reported, S384N and G144R, were found in only one allele. In addition, three polymorphisms previously described (V358M, V376M and P397P) were detected in the patients analysed. Our findings are in agreement with the literature confirming the great genetic heterogeneity associated with MPS VI.
A novel deletion in a Pearson syndrome infant with hypospadias and cleft lip and palate
Authors: Lohi O. , Kuusela A. L. , Arola M. 
Published: January 2006

SummaryPearson syndrome is a rare multiorgan mitochondrial disorder that causes substantial disability and usually leads to premature death. We describe an infant with Pearson syndrome who showed, in addition to the typical features of the syndrome, cleft lip and palate and hypospadias.
The intake of total protein, natural protein and protein substitute and growth of height and head circumference in Dutch infants with phenylketonuria
Authors: Hoeksma M. , Van Rijn M. , Verkerk P. H. , Bosch A. M. , Mulder M. F. , de Klerk J. B. C. , De Koning T. J. , Rubio‐Gozalbo E. , De Vries M. , Sauer P. J. J. , van Spronsen F. J. 
Published: January 2006

SummaryIn a previous study, Dutch children with phenylketonuria (PKU) were found to be slightly shorter than their healthy counterparts. In the literature, it has been hypothesized that a higher protein intake is necessary to optimize growth in PKU patients. The study aimed to investigate whether protein intake (total, natural and protein substitute) in this group might be an explanatory factor for the observed growth. Growth of height and head circumference and dietary data on protein intake (total, natural and protein substitute) from 174 Dutch PKU patients born between 1974 and 1996 were analysed retrospectively for the patients' first 3 years of life. Analyses were corrected for energy intake during the first year of life and for the clinical severity of the deficiency of phenylalanine hydroxylase by means of plasma phenylalanine concentration at birth. Neither protein nor energy intake correlated with height growth. A positive, statistically significant relation between head circumference growth and natural protein and total protein intake was found, but not with the intake of the protein substitute or energy. Therefore, this study suggests that improvement of the protein substitute rather than an increase of total protein intake may be important in optimizing head circumference growth in PKU patients.
The knowledge gap in expanded newborn screening: Survey results from paediatricians in Massachusetts
Authors: Gennaccaro M. , Waisbren S. E. , Marsden D. 
Published: January 2006

SummaryMassachusetts currently offers an optional expanded newborn screening programme that tests for 20 biochemical genetic disorders in addition to the mandated newborn screening tests, including phenylketonuria (PKU) and nine other biochemical genetic disorders. We conducted a mail survey of 550 paediatricians listed in the 2000Massachusetts Healthcare Directory to determine paediatricians' preparedness in discussing expanded newborn screening and its results with families, and to determine in what specific format physicians in Massachusetts would prefer to receive educational materials and updates. Of surveys mailed, 35% (190/550) were returned within the allotted 3 weeks: 25 paediatricians (14%) were unaware of expanded newborn screening; 78 respondents (42%) indicated feeling less than prepared talking about test results with families; 100 paediatricians (54%) indicated a lack of information about metabolic disorders; 134 (73%) preferred information sent in postal mailings, 62 (34%) preferred grand rounds, 60 (33%) preferred educational seminars, and 58 (32%) preferred websites. Other formats receiving preferences of less than 30% included e‐mail (27%), phone calls (8%), video (6%), and distance learning (1%). Paediatricians are ill‐prepared for expanded newborn screening for biochemical genetic disorders. To address this problem, paediatricians in Massachusetts indicated a preference for unsolicited periodic mailings including short reviews and brochures.
Body composition in children with galactosaemia
Authors: Panis B. , Forget P. Ph. , Nieman F. H. , van Kroonenburgh M. J. P. G. , RubioGozalbo M. E. 
Published: January 2006

SummaryBody composition in classical galactosaemia has not been studied. Patients with classical galactosaemia, an inherited disorder of galactose metabolism caused by deficiency of galactose‐1‐phosphate uridyltransferase (GALT, EC 2.7.7.10), might be at risk for an abnormal body composition because of intrinsic factors related to galactosaemia and/or diet‐related factors. The aim of this study was to evaluate the body composition of children with classical galactosaemia. The studied population was a previously reported group of classical galactosaemia patients (13 male and 27 female, ages 3–17 years) with decreased height, weight, weight‐for‐height and insulin‐like growth factor‐I (IGF‐I) Z‐scores. Body composition data were obtained by dual‐energy X‐ray absorptiometry (DXA). In order to correct for height, fat mass (FM) and lean tissue mass (LTM) were divided by squared height. Mid‐parental target height Z‐scores were assessed and compared to actual height Z‐scores. Linear and multiple regression analysis were done to investigate the relationship between body composition and IGF‐I, dietary intake and growth data. We found decreased height Z‐scores when compared to mid‐parental target height Z‐scores. Mean scores for FM and LTM (both adjusted for height) were decreased. LTM (adjusted for height) and height Z‐score were correlated with IGF‐I Z‐score. FM (adjusted for height) was correlated with soy intake. No correlation was found between soy intake and IGF‐I Z‐score. In this limited group of patients, height is decreased and body composition is abnormal. The decreased levels of IGF‐I and/or soy nutrition might play a role in these findings.
External quality assurance programme for enzymatic analysis of lysosomal storage diseases: A pilot study
Authors: Ruijter G. J. G. , Boer M. , Weykamp C. W. , De Vries R. , van den Berg I. , Janssens‐Puister J. , Niezen‐Koning K. , Wevers R. A. , Poorthuis B. J. H. M. , van Diggelen O. P. 
Published: January 2006

AbstractInborn errors of metabolism are rare and laboratories performing diagnostic tests in this field must participate in external quality assurance (EQA) schemes to demonstrate their competence and also to maintain sufficient experience with patient material. EQA schemes for metabolite analyses are available (ERNDIM), but corresponding EQA schemes for enzyme analyses are nonexistent. In this paper we describe a pilot study on lysosomal enzyme testing by four centres in The Netherlands. Quantitative aspects of EQA were studied by interlaboratory comparison of activities of six lysosomal enzymes in a series of buffy coat samples. Interlaboratory variance was enormous. To reduce variance caused by methodological differences, participants reported enzyme activities relative to mean normal values. β‐D‐Galactosidase activities compared well between the participating laboratories (average interlaboratory CV 13%), but for other enzymes large differences were observed, e.g. sphingomyelinase (average CV 38%). Diagnostic proficiency was tested with cultured fibroblasts. In 45 out of a total of 48 tests (12 cell lines, 4 participants) the correct diagnosis was accomplished on the basis of merely biochemical investigations, i.e. without clinical data of the patients. In a survey using blood of a late‐onset Pompe disease patient, less conclusive results were obtained. A stable enzyme source was developed for easy distribution. Most lysosomal enzymes were stable upon lyophilization of leukocyte homogenates and during subsequent storage of the freeze‐dried material at room temperature, in particular when cryolyoprotectant was added. Shipment of such lyophilized samples is simple and cheap and ideal for an EQA scheme. Our study shows that an EQA programme for enzymatic testing of lysosomal storage diseases is necessary to accomplish reliable diagnostic procedures for lysosomal storage diseases. We recommend that EQA for lysosomal enzymes be implemented through ERNDIM.
Anxiety and depression in the acute porphyrias
Authors: Millward L. M. , Kelly P. , King A. , Peters T. J. 
Published: January 2006

SummaryA previous study of self‐rated psychosocial aspects in patients with acute porphyria found that depression, and particularly anxiety, is more common in porphyria patients than in the general population or general medical outpatient attenders. Nearly half of the sample (46%) reported at least some problem with anxiety and/or depression: anxiety caseness was 26% and depression caseness was 13%. This paper extends our previous observations and investigates further the associations between porphyria and anxiety, depression and general mental health in 90 patients (58 acute intermittent porphyria, 32 variegate porphyria). The findings of this study confirm that anxiety is raised in patients with acute intermittent porphyria and with variegate porphyria, in both males and females, compared to the normative population and, using a series of questionnaires exploring the physical and psychosocial features of anxiety, that this anxiety is experienced as a ‘relatively stable personality trait’, rather than a ‘transitory emotional state’ (i.e. intrinsic rather than secondary to the porphyria).
Clinical, biochemical, magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (1H MRS) findings in a fourth case of combined D‐ and L‐2 hydroxyglutaric aciduria
Authors: Read M.‐H. , Bonamy C. , Laloum D. , Belloy F. , Constans J. M. , Guillois B. , Kottler M.‐L. , Verhoeven N. M. , Jakobs C. 
Published: January 2006

SummaryWe report the fourth case of combined d‐and L‐2‐hydroxyglutaric aciduria presenting with neonatal encephalopathy and subependymal cysts.
Older People's Experiences of Loneliness in the UK: Does Gender Matter?
Authors: Victor Christina R. , Scambler Sasha J. , Marston Louise , Bond John , Bowling Ann 
Published: January 2006

The extent and nature of loneliness in later life does not show a consistent relationship with gender. Our study investigates whether there are differences in the nature and extent of loneliness amongst older men and women in contemporary Britain.Loneliness was measured using a self-report four-point scale in a nationally representative survey of people aged 65+ living in the community.Survey response rate was 77 per cent and the sample of 999 approximates to that of the general population. Approximately half of our sample 53 per cent were women. Compared with males in the sample women were significantly more likely to be widowed, live alone and have direct contact with friends and relatives. Preliminary analysis identified statistically significant differences between men and women in and self-reported loneliness (and changes over the previous decade). Ordered logistic regression, indicated that gender was no longer independently associated with loneliness once the confounding influences of marital status, age and living arrangement were excluded.The overall self-reported prevalence of severe loneliness shows little difference between men and women, challenging the stereotype that loneliness is a specifically female experience.
Oviposition deterrents for the Mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae) from fly faeces extracts
Authors: Arredondo J. , Díaz-Fleischer F. 
Published: January 2006

AbstractAfter oviposition, females of the Mediterranean fruit fly Ceratitis capitata Wiedemann deposit a host-marking pheromone on the fruit surface that deters oviposition by conspecifics. Methanolic extracts of fruit fly faeces elicit a similar deterrent effect. The results of laboratory and field experiments using raw methanolic extracts of C. capitata faeces as an oviposition deterrent are reported. Laboratory bioassays revealed a significant positive relationship between concentration of faeces and the inhibition of oviposition responses by C. capitata. Treatment of halves of coffee bushes with methanolic extracts containing 0.1, 1.0 and 10 mg faeces ml−1 resulted in a significant reduction of infestation only at the highest concentration (P = 0.03). Treatment of blocks of coffee bushes with an extract of 10 mg faeces ml−1 resulted in an 84%reduction in infestation by C. capitata in sprayed plants and a 56% reduction in adjacent untreated coffee bushes surrounding treated plots, probably due to the deterrent effect of host-marking pheromone on fly oviposition. We conclude that faeces contain oviposition deterrent substances that effectively reduce fruit infestations by C. capitata, suggesting a clear potential for the use of this infochemical in integrated management programmes targeted at this pest.
Aspects of the biology of Tilapia mossambica Peters (Pisces: Cichlidae) in a natural freshwater lake (Lake Sibaya, South Africa)
Authors: Bruton M. N. , Boltt R. E. 
Published: January 2006

An account is given of some aspects of the biology of Tilapia mossambica Peters in Lake Sibaya, South Africa. Lake Sibaya is a warm shallow coastal lake with extensive shallow terraces in the littoral which shelve abruptly into underwater valleys. The substrate is predominantly sandy. Aquatic macrophytes are generally restricted to water 1–7 m deep. Adult fishes (over 8 cm standard length) are usually absent from water deeper than 12m and shallower than 0–5 m, whereas juveniles may occur at all depths, and fry only in very shallow water. T. mossambica inhabits the littoral and sublittoral in the warm and transition periods (August–April) but moves into deep water in the cool season (May–July). Exposed and sheltered areas are utilized for different purposes by adult fishes, the former for nesting, and latter for feeding and mouth–brooding. Habitat selection by males is governed by the availability of suitable nest sites. Nests are most common in sparsely–vegetated sheltered areas. Brooding females preferred sheltered littoral areas but ventured onto the terrace to release the fry. Juveniles and fry inhabited exposed shores with a temperature gradient which reversed diurnally. The breeding, shoaling and feeding behaviour is described. The biology of T. mossambica in Lake Sibaya is compared to data on the same, and similar species, in other systems. The utilization of available resources in the lake by T. mossambica is discussed and reference is made to the importance of the retention of generalized characters for the successful habitation of the cyclically–renewed habitat of the littoral.
The fish populations in inshore waters of the west of Scotland. The Biology of the Norway Pout (Trisopterus esmarkii)
Authors: Gordon J. D. M. 
Published: January 2006

Norway pout (Trisopterus esmarkii) were collected during a trawling survey of inshore waters of the west coast of Scotland. 0–group fish were first taken by the bottom trawl in late summer and since there was no evidence of local spawning it was inferred that a migration from the open sea had occurred. The distribution and age composition of the stock was related to depth. The young fish migrated from the shallower stations during their first winter but persisted for a second winter at some of the deeper stations.There was a marked seasonal variation in the quality of the diet and in the intensity of feeding. The most important food organisms were copepods, decapod larvae, mysids and euphausiids. Diurnal variations in the intensity of feeding were minimal in August but the quality of the food in the stomachs was dependent on the time of sampling. The converse was observed in January when feeding was at a maximum between dusk and dawn but the quality of the food remained fairly constant.
Lipid mobilization during starvation in the rainbow trout, Salmo gairdneri Richardson, with attention to fatty acids
Authors: Jezierska B. , Hazel J. R. , Gerking S. D. 
Published: January 2006

Rainbow trout, Salmo gairdneri, were fed pelleted food ad libitum for 35 and 50 days. Lipid deposits were determined in the viscera, liver and muscle (epaxial and hypaxial). Most of the lipid accumulated in the viscera, but the lipid content of liver and epaxial muscle also increased. Hypaxial muscle lipid content remained the same throughout the feeding period. Upon starving the fish for 27 and 48 days following 50 days of feeding, visceral lipid contributed most to energy metabolism among the depots investigated. Muscle also contributed a considerable share while the absolute amount derived from the liver was much smaller.Patterns of fatty acid mobilization during starvation were also investigated. Saturated acids were preferentially mobilized from the viscera, resulting in a rise in the percentage of monoenes and polyunsaturates. In liver, the percentage of saturates remained relatively constant whereas the percentage of monoenes declined and polyunsaturates increased. In muscle, a substantial increase in saturates was caused by a decline in monoenes; polyunsaturate content remained constant. As a result of these shifts in relative fatty acid composition the U/S (unsaturates to saturates) ratio rose in viscera and liver and decreased in muscle. The UI (unsaturation index) responded in essentially the same way. Possible explanations for preferential fatty acid utilization are discussed in terms of energetics and structural relationships.
Growth and respiration of two pleuronectiform juveniles from a western Mediterranean bay
Authors: de Morais L. Tito 
Published: January 2006

Growth and respiration of juveniles of two pleuronectiforms (Buglossidium luteum and Arnoglossus thori) were studied. The first species has a single period of benthic recruitment (April), a growth pause in winter, and a very low winter metabolism (at 11°C). The second species has two peaks of recruitment (May–June and September–October), an exponential growth with no significant pause in winter, and little reduction of metabolism at 11°C.Such differences are important factors allowing the sharing of the same biotope by these small benthic predators.
Effects of advanced photoperiod cycle on the epidermis and gonadosomatic index of 2‐year‐old rainbow trout, Salmo gairdneri R., reared at natural temperature
Authors: Nakari T. , Soivio A. , Pesonen S. 
Published: January 2006

Sexual dimorphism was shown in the epidermis of 2‐year‐old rainbow trout. The changes in the epidermis which appear normally at the spawning time can be timed earlier by advancing the normal annual photoperiod cycle by three months.The epidermis of the advanced fish was significantly thicker than that of the control fish during the winter preceding spawning. For most of the year the epidermis of the males was thicker than that of the females, but females had more mucous cells in the epidermis than males. The maximum concentration of plasma testosterone coincided with the epidermal thickening.