bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic polyandry and sexual conflict in the sandbar shark,Carcharhinus plumbeus, in the western North Atlantic and Gulf of Mexico
Authors: PORTNOY DAVID S. , PIERCY ANDREW N. , MUSICK JOHN A. , BURGESS GEORGE H. , GRAVES JOHN E. 
Published: October 2006

AbstractTo investigate patterns of polyandry in the sandbar shark (Carcharhinus plumbeus), 20 pregnant females were sampled from the western North Atlantic and Gulf of Mexico. Five species‐specific microsatellite markers were used to genotype each shark and its litter. Of 20 litters, 17 (85%) were shown to have multiple sires. In multiply sired litters, the estimated minimum number of sires ranged from two to five with an average of 2.3 males per litter. Regression analysis did not demonstrate a significant relationship between female reproductive success and female body size or sire number and female body size. There was a high incidence of reproductive skew noted in litters, and two groups of males with significantly different mean reproductive success were observed. Analyses using Bateman's principles suggest that there is less direct benefit for females that acquire multiple mates than for males who bias paternity within litters. In light of past morphological and behavioural studies, these data suggest that patterns of polyandry in elasmobranchs may be determined by coercive mating, and that breeding behaviour has likely evolved in the context of sexual conflict.
Local‐scale genetic structure in the peatmoss Sphagnum fuscum
Authors: GUNNARSSON U. , SHAW A. J. , LÖNN M. 
Published: October 2006

Abstract Sphagnum (peatmoss) dominates huge areas of the Northern Hemisphere and acts as a significant carbon sink on a global scale, yet little is known about the genetic structure of Sphagnum populations. We investigated genetic structure within a population of the common peatmoss Sphagnum fuscum, to assess local patterns of genetic diversity and the spatial extent of clones. One hundred seventeen shoots were sampled from five transects in Fuglmyra, central Norway, and sequenced for three anonymous DNA regions. Five neighbourhood patches were marked along each transect, and from each patch, five stems were sampled for molecular analyses. Seventeen haplotypes could be distinguished and two major groups of haplotypes differed by 12 mutational steps. The two major haplotype groups differed significantly in microhabitat association along the distance to groundwater table and the pH gradients, indicating microhabitat differentiation. The haplotypes within these groups were all genetically similar, differing by one or two mutations. The most common haplotype occurred in four transects separated by 250‐m distance. Most of the molecular variation in the population was found among transects, and within patches. Large dominating clones within each transect resulted in low variation explained by the among‐patch‐within‐transect component of spatial structure. Mutation appears to account for a larger proportion of the population variation than recombination. Within the population, vegetative growth and asexual reproduction from gametophyte fragments dominate as the main reproductive mode.
The exceptionally tight affinity of DnaA for ATP/ADP requires a unique aspartic acid residue in the AAA+ sensor 1 motif
Authors: Kawakami Hironori , Ozaki Shogo , Suzuki Shigeo , Nakamura Kenta , Senriuchi Takayuki , Su'etsugu Masayuki , Fujimitsu Kazuyuki , Katayama Tsutomu 
Published: October 2006

Summary Escherichia coli DnaA, an AAA+ superfamily protein, initiates chromosomal replication in an ATP‐binding‐dependent manner. Although DnaA has conserved Walker A/B motifs, it binds adenine nucleotides 10‐ to 100‐fold more tightly than do many other AAA+ proteins. This study shows that the DnaA Asp‐269 residue, located in the sensor 1 motif, plays a specific role in supporting high‐affinity ATP/ADP binding. The affinity of the DnaA D269A mutant for ATP/ADP is at least 10‐ to 100‐fold reduced compared with that of the wild‐type and DnaA R270A proteins. In contrast, the abilities of DnaA D269A to bind a typical DnaA box, unwind oriC duplex in the presence of elevated concentrations of ATP, load DnaB onto DNA and support minichromosomal replication in a reconstituted system are retained. Whereas the acidic Asp residue is highly conserved among eubacterial DnaA homologues, the corresponding residue in many other AAA+ proteins is Asn/Thr and in some AAA+ proteins these neutral residues are essential for ATP hydrolysis but not ATP binding. As the intrinsic ATPase activity of DnaA is extremely weak, this study reveals a novel and specific function for the sensor 1 motif in tight ATP/ADP binding, one that depends on the alternate key residue Asp.
Low birthweight and mortality: the tendency to repeat low birthweight and its association with early neonatal and infant morbidity and mortality
Authors: Bakketeig Leiv S. , Jacobsen Geir , Skjærven Rolv , Carneiro Isabella G. , Knudsen Lisbeth B. 
Published: October 2006

SummaryPrevious studies have demonstrated the tendency to repeat gestational age and birthweight in successive pregnancies and that this tendency is associated with infant survival. Thus, newborn outcome and survival is less favourable if the gestational age and size departs from this maternal tendency. This paper aims to study diseases or conditions that might be associated with this effect. Data were provided through a linkage between three Danish health registries: the Danish Fertility Database, the National Hospital Registry, and the Registry for Preventive Medicine. Such linkage was possible due to the use of unique ID‐person numbers. The study included all 8219 second‐order low‐birthweight (LBW) singleton Danish births, 1980–94, of whom 7811 were liveborn. It was also required that the mother's first delivery took place during that period. The analysis considered 7803 of these births; eight were excluded due to insufficient information. Of the second‐order LBW children, 26% had an elder sibling who was also LBW.Early neonatal mortality of a ‘non‐repeat’ LBW birth was 1.3 times higher than ‘repeat’ LBW births [53.8 vs. 41.2 per 1000; RR 1.31; 95% CI 1.03, 1.65], as was infant mortality [78.4 vs. 60.8 per 1000; RR 1.30; 95% CI 1.06, 1.56]. Also, proportionately more LBW repeat births had Apgar scores of ≥7 after 1 and 5 min. Overall, repeat second‐order LBW babies weighed 68 g more than non‐repeat LBW babies (P < 0.001). At term, the weight difference was 160 g higher among repeat LBW births (P < 0.001). The mean number of hospitalisations during the first year of life was lower among repeat than non‐repeat LBW babies (2.30 vs. 2.46, P < 0.001), while the mean duration of stay was 23.71 vs. 23.97 days (P > 0.05). Newborn immaturity was the most common diagnosis for hospitalisation, and infections the second most common. There were no differences between repeat and non‐repeat LBW births in the proportion with each diagnosis. Apart from the differences in birthweight, we were unable to explain the improved survival for repeat compared with non‐repeat LBW babies. Except for differences in Apgar scores, we observed no differences in morbidity based on registered hospitalisations during infancy.
Immunological exposures in Norwegian agriculture and pre‐eclampsia
Authors: Nordby Karl‐Christian , Irgens Lorentz M. , Kristensen Petter 
Published: October 2006

SummaryImmune system perturbations are involved in pre‐eclampsia pathophysiology. We hypothesised that immunomodulating substances, such as mycotoxins, endotoxins or pesticides, affect pre‐eclampsia risk. Associations between indicators of immunomodulating exposures in agriculture and pre‐eclampsia are reported.In a Norwegian family cohort based on participants in agricultural censuses conducted by Statistics Norway 1969–89, 183 313 pregnancies to farmers were identified in the Medical Birth Registry of Norway. Cases notified as pre‐eclampsia as well as pregnancies indicated by hypertension in combination with proteinuria were included. Data on farm production and meteorologically based fungal forecasts 1973–90 (a marker of temperate and humid climatic conditions known to favour fungal growth and mycotoxin formation in grain) were obtained and allocated to each farm. Pre‐eclampsia prevalence rates were studied in strata of exposure indicators using Poisson regression models. Adjusted rate ratios (RR) and 95% confidence intervals [CI] were computed.We identified 4912 cases, equivalent to 26.8 pre‐eclampsia cases per 1000 pregnancies [95% CI 26.1, 27.6]. Pre‐eclampsia showed moderate associations with animal farming, RR 1.14, [95% CI 1.07, 1.22] and moderate negative associations with grain production, RR 0.93, [95% CI 0.86, 1.01], and two or more fungal forecasts appearing in any year 1973–90, RR 0.90 [95% CI 0.84, 0.97], using no years with two or more forecasts as reference.Exposure to immunomodulating substances as indicated by grain farming, animal farming and fungal warnings could possibly have moderate effects on pre‐eclampsia risk, thus supporting the study hypothesis. The use of exposure indicators as surrogates for real exposures may introduce a non‐differential misclassification of the exposure that would attenuate any true exposure–outcome association. The use of exposure proxies warrants that inferences from the study should be made with caution.
Allopurinol as an adjunct to lithium and haloperidol for treatment of patients with acute mania: a double‐blind, randomized, placebo‐controlled trial
Authors: Akhondzadeh Shahin , Milajerdi Mehdi Rafiee , Amini Homayoun , Tehrani‐Doost Mehdi 
Published: October 2006

Objective:  Allopurinol, a hypouricemic agent, has been shown to present therapeutic effects in mania associated with hyperuricemia. This study assessed the efficacy and safety of risperidone as an adjunctive agent to lithium and haloperidol for the treatment of acute mania in hospitalized bipolar patients.Methods:  Eighty‐two patients aged between 18 and 49 were eligible to participate, as they met the DSM‐IV criteria for a current manic episode, on the basis of a clinical interview by two academician psychiatrists. In addition, a score of at least 20 points on the Young Mania Rating Scale was required representing at least a moderate‐to‐severe mania. Forty‐one patients were randomly allocated to lithium (1–1.2 mEq/L) + haloperidol (10 mg/day) + allopurinol (300 mg/day) (group A) or lithium (1–1.2 mEq/L) + haloperidol (10 mg/day) + placebo (group B) for an 8‐week, double‐blind, placebo‐controlled study. Patients were assessed by a third‐year resident of psychiatry at baseline and at 7, 14, 28, 42, and 56 days after the medication started. The mean decrease in the Young Mania Rating Scale score from baseline was used as the main outcome measure of response of mania to treatment. The extrapyramidal symptoms were assessed using the Extrapyramidal Symptoms Rating Scale (ESRS). Side effects were systematically recorded throughout the study and were assessed using a checklist.Results:  Young Mania Rating Scale scores improved with allopurinol. The difference between the two protocols was significant as indicated by the effect of the group, the between‐subjects factor (F = 5.22, df = 1, p = 0.008). The mean ESRS scores for the placebo group were higher than the allopurinol group. However, the differences were not significant over the trial. The difference between the two groups in the frequency of side effects was not significant except for agitation that was more often in the placebo group.Conclusions:  The efficacy of allopurinol to obtain a greater improvement in patients with mania seems to support the purinergic dysfunction in mania.
Rational approaches to the neurobiologic study of youth at risk for bipolar disorder and suicide
Authors: Elizabeth Sublette M , Oquendo Maria A , John Mann J 
Published: October 2006

Objectives:  The aims of this paper are to provide an overview of neuroimaging findings specific to bipolar disorder and suicide, and to consider rational approaches to the design of future in vivo studies in youth at risk.Methods:  Neuroimaging and related neurobiological literature pertaining to bipolar disorder and suicide in adult and pediatric samples was reviewed in a non‐quantitative manner.Results:  Specific structural and functional brain findings in bipolar disorder are described, where possible in the context of relevant current neurobiological theories of etiology. Diagnostic and prognostic implications are discussed.Conclusions:  The simultaneous use of complementary neurobiological approaches may be a powerful way of identifying and validating factors reliably associated with bipolar disorder and suicide. A profile of neurobiological markers with which to screen for bipolar disorder and suicide risk may provide for earlier and more accurate diagnosis, perhaps even in the pre‐ or subsyndromal stages in high‐risk youth.
A novel technique to evaluate fluctuations of mood: implications for evaluating course and treatment effects in bipolar/affective disorders
Authors: Sree Hari Rao V , Raghvendra Rao C , Yeragani Vikram K 
Published: October 2006

Objectives:  Several psychiatric conditions are associated with frequent fluctuations of affect. In this study, we propose a new technique to uniformly score depression and mania objectively and use a new mathematical technique to model the frequent fluctuations in mood using simulated data. Our main aim is to examine the usefulness of this measure for evaluating treatment effects or course of illness, especially in bipolar or unipolar affective illness to quantify mood fluctuations.Methods:  We use a prototypical model, which takes into account the mean, the standard deviation (SD) and the coefficient of variation (CV = SD*100/mean) of the mood scores of the subjects over a user‐defined period. We utilize simulated data of subjects for euthymia, minor depression, minor mania, severe depression, severe mania and cyclic bipolar illness (manic depression, MDP). We propose an objective method to quantify the mood of the subjects at weekly intervals (the interval can be user‐defined) using a scale of 1–9 (1–4 = degrees of depression, 5 = euthymia, 6–9 = degrees of mania). These scores can be sampled according to the convenience and feasibility of the measurements, which can be derived from various clinical scales or by observation of the subjects in hospitals or other environments. We derive a new mathematical technique to arrive at a normalized measure for each of these conditions of simulated data in addition to the mean, SD and approximate entropy (ApEn).Results:  We utilize three sets of data, one to train the model to classify the condition of the subjects and the other two to test the reliability of the technique. We are able to successfully classify the condition of the subjects over a 52‐timepoint period (length can be days or weeks depending upon the sampling rate). The New Index (NI) correlates significantly only with the mean (r2 = 0.78), but not with the SD or ApEn score.Conclusions:  These results indicate that it may be beneficial to reduce data according to the techniques we propose so that there is greater uniformity within which to compare future studies to evaluate treatment effects, not only in rapid‐cycling MDP but also in other affective disorders. This method may be suitable for the meta‐analysis of several studies, although different scales have been used in each of those studies. Our measure derived from simulated data has shown sufficient deviation of all the abnormal states from the euthymic state. The advantages and pitfalls of these techniques are further discussed to evaluate affect in various disorders. However, future prospective studies must address the importance of this measure in comparison with mean, SD and ApEn scores or other nonlinear measures of these time series. We are evaluating other nonlinear dynamic models, which may provide a continuous measure with which to identify different degrees of fluctuation of mood.
A comparison of the medical lethality of suicide attempts in bipolar and major depressive disorders
Authors: Zalsman Gil , Braun Melanie , Arendt Mikkel , Grunebaum Michael F , Sher Leo , Burke Ainsley K , Brent David A , Chaudhury Sadia R , John Mann J , Oquendo Maria A 
Published: October 2006

Objectives:  Among mood disorders, bipolar disorder (BPD) is often noted to involve the highest rates of suicide attempts and possibly of completion. This study sought to determine whether suicide attempters with BPD exhibit suicide attempts with higher lethality than attempters with major depressive disorder (MDD) and to explore differences in clinical features associated with suicidal acts.Methods:  Mood disordered suicide attempters were interviewed about Axis I and II diagnoses, lifetime history of suicide attempts, suicidal intent, suicidal ideation, the medical lethality of their most severe suicide attempt, severity of depression, hopelessness, lifetime aggression, and impulsivity.Results:  The maximum lethality of suicidal acts tended to be higher among BPD attempters compared with those with MDD. However, there were no differences in the number of suicide attempts, intent to die or suicidal ideation. Suicide attempters with BPD reported higher levels of aggression and impulsivity but less hopelessness compared with MDD attempters. These differences could not be explained by Cluster B personality disorder comorbidity. Of note, within the BPD group, but not the MDD group, males reported suicidal acts with higher lethality. Multivariate analyses suggested that risk for more lethal suicide attempts is associated with BPD and male sex and that bipolar males appear to be especially vulnerable to these behaviors.Conclusions:  Males with BPD make more lethal suicide attempts than females with BPD, an effect not observed among the MDD sample. Our findings suggest that higher rates of suicidal behavior in BPD may be due to a specific effect of BPD on males, leading to more dangerous suicidal behaviors. This effect, together with the larger proportion of males in the BPD group compared with the MDD group may lead to higher rates of reported attempted and completed suicide.
Social semantics: altruism, cooperation, mutualism, strong reciprocity and group selection
Authors: WEST S. A. , GRIFFIN A. S. , GARDNER A. 
Published: October 2006

AbstractFrom an evolutionary perspective, social behaviours are those which have fitness consequences for both the individual that performs the behaviour, and another individual. Over the last 43 years, a huge theoretical and empirical literature has developed on this topic. However, progress is often hindered by poor communication between scientists, with different people using the same term to mean different things, or different terms to mean the same thing. This can obscure what is biologically important, and what is not. The potential for such semantic confusion is greatest with interdisciplinary research. Our aim here is to address issues of semantic confusion that have arisen with research on the problem of cooperation. In particular, we: (i) discuss confusion over the terms kin selection, mutualism, mutual benefit, cooperation, altruism, reciprocal altruism, weak altruism, altruistic punishment, strong reciprocity, group selection and direct fitness; (ii) emphasize the need to distinguish between proximate (mechanism) and ultimate (survival value) explanations of behaviours. We draw examples from all areas, but especially recent work on humans and microbes.
Selection on flowering time and floral display in an alpine and a lowland population of Arabidopsis lyrata
Authors: SANDRING S. , RIIHIMÄKI M.‐A. , SAVOLAINEN O. , ÅGREN J. 
Published: October 2006

AbstractTo determine whether population differentiation in flowering time is consistent with differences in current selection, we quantified phenotypic selection acting through female reproductive success on flowering phenology and floral display in two Scandinavian populations of the outcrossing, perennial herb Arabidopsis lyrata in two years. One population was located in an alpine environment strongly affected by grazing, whereas the other was close to sea level and only moderately affected by herbivory. Multiple regression models indicated directional selection for early end of flowering in one year in the lowland population, and directional selection for early start of flowering in one year in the alpine population. As expected, there was selection for more inflorescences in the lowland population. However, in the alpine population, plants with many inflorescences were selectively grazed and the number of inflorescences produced was negatively related to female fitness in one year and not significantly related to female fitness in the second year. The results are consistent with the hypothesis that genetic differentiation in flowering phenology between the study populations is adaptive, and indicate that interactions with selective grazers may strongly influence selection on floral display in A. lyrata.
Primary Hyperaldosteronism in a Dog with Concurrent Lymphoma
Authors: Johnson K. D. , Henry C. J. , McCaw D. L. , Turnquist S. E. , Stoll M. R. , Kiupel M. , Bondy P. J. 
Published: October 2006

SummaryAn 11‐year‐old, male castrated English springer spaniel was presented for muscle weakness, lethargy and anorexia while undergoing treatment of Stage IV lymphoma. Persistent hypokalemia prompted multiple diagnostic tests. Serum aldosterone levels, surgical exploration and histopathology confirmed primary hyperaldosteronism. Hyperaldosteronism is a rarely reported endocrinopathy in the dog. This report describes a case in which immunohistochemistry was utilized to confirm the diagnosis of an aldosterone‐secreting tumour.
ALTERING EXTRACELLULAR POTASSIUM CONCENTRATION DOES NOT MODULATE DRUG BLOCK OF HUMAN ETHER‐A‐GO‐GO‐RELATED GENE (hERG) CHANNELS
Authors: Limberis James T , Su Zhi , Cox Bryan F , Gintant Gary A , Martin Ruth L 
Published: October 2006

SUMMARY

Drug‐induced block of the rapidly activating delayed rectifier K+ current (IKr), encoded by human ether‐a‐go‐go‐related gene (hERG), has been linked to acquired long QT syndrome (aLQTS). Hypokalaemia is a recognized risk factor in aLQTS. To further understand why hypokalaemia is a risk factor in aLQTS, we examined the effect of [K+]o on drug block of the hERG potassium channel stably expressed in human embryonic kidney (HEK‐293) cells using whole‐cell voltage‐clamp techniques.
The effects of selected [K+]o (1–20 mmol/L) on hERG block with four structurally diverse compounds (dofetilide, mesoridazine, quinidine and terfenadine) from different therapeutic classes were evaluated. Reducing [K+]o from 20 to 1 mmol/L had little effect on IC50 values for hERG current block for all four compounds. For example, evaluating quinidine in external potassium concentrations of 20, 10, 5 and 1 mmol/L resulted in IC50 values of 1.82 ± 0.33, 2.04 ± 0.28, 1.57 ± 0.52 and 1.14 ± 0.21 mmol/L, respectively. No statistically significant difference (P > 0.35, anova) was observed between drug block of hERG in different external potassium concentrations. These data are in contrast with previously reported results examining hERG channel modulation expressed in AT‐1 cells under similar experimental conditions.
These results demonstrate that [K+]o does not directly modulate drug block of hERG channels expressed in an HEK‐293 cell line. The enhanced risk of Torsades de Pointes associated with hypokalaemia in aLQTS may be due to reduction of other (non‐hERG) potassium currents, further reducing the repolarization reserve, and not due to direct modulation of hERG block by [K+]o.