bluuebunny/crossref_metadata_2025 huggingface dataset:
Distribution of plasma levels of adiponectin and leptin in an adult Caucasian population
Authors: Marques‐Vidal Pedro , Bochud Murielle , Paccaud Fred , Mooser Vincent , Waeber Gérard , Vollenweider Peter
Published: May 2009

Objectives  Little is known regarding the distribution and the determinants of leptin and adiponectin levels in the general population.

Design  Cross‐sectional study.

Patients  Women (3004) and men (2552) aged 35–74 living in Lausanne, Switzerland.

Measurements  Plasma levels of leptin and adiponectin (ELISA measurement).

Results  Women had higher leptin and adiponectin levels than men. In both genders, leptin and adiponectin levels increased with age. After adjusting for fat mass, leptin levels were significantly and negatively associated with age in women: 18·1 ± 0·3, 17·1 ± 0·3, 16·7 ± 0·3 and 15·5 ± 0·4 ng/ml (adjusted mean ± SE) for age groups [35–44], [45–54], [55–64] and [65–75], respectively, P < 0·001. A similar but nonsignificant trend was also found in men. Conversely, the age‐related increase of adiponectin was unrelated to body fat in both genders. Post‐menopausal women had higher leptin and adiponectin levels than premenopausal women, independently of hormone replacement therapy. Although body fat mass was associated with leptin and adiponectin, the associations were stronger with body mass index (BMI), waist and hip in both genders. Finally, after adjusting for age and anthropometry, no relationships were found between leptin or adiponectin levels with alcohol, caffeine consumption and physical activity, whereas smoking and diabetes decreased leptin and adiponectin levels in women only.

Conclusions  The age‐related increase in leptin levels is attributable to changes in fat mass in women and probably also in men. Leptin and adiponectin levels are more related to BMI than to body fat mass. The effects of smoking and diabetes appear to be gender‐specific.
Absence of activating mutations of CXCR4 in pituitary tumours
Authors: Lee Yong‐ho , Noh Tae Woong , Lee Mi Kyung , Jameson J. Larry , Lee Eun Jig
Published: May 2009

Objective  Mutations of the gsp oncogene are responsible for 30–40% of GH‐producing pituitary adenomas and 10% of nonfunctioning pituitary adenomas (NFPAs). However, the pathogenetic mechanism of the remaining pituitary tumours still remains to be identified. Recently, the interaction between the chemokine stromal cell‐derived factor 1 and its receptor CXCR4 was found to play an important role in GH production and cell proliferation in various pituitary adenoma cell lines. As CXCR4 is a Gi‐coupled chemokine receptor, its constitutive activating mutations may be involved in pituitary tumour formation by cyclic adenosine monophosphate (cAMP)‐independent, ERK‐related pathways.

Patients and methods  We investigated whether somatic activating‐mutations of CXCR4 might be a possible tumourigenic mechanism for gsp‐negative GH‐secreting pituitary adenomas and NFPAs. Direct sequencing of polymerase chain reaction‐amplified products for coding exons of CXCR4 were performed using genomic deoxyribonucleic acid samples from 37 GH‐producing pituitary tumour tissues that were negative for the gsp mutation and 14 CXCR4 expressing NFPAs.

Results  Immunohistochemical analyses and double immunofluorescent staining of sectioned paraffin‐embedded pituitary tissues revealed that CXCR4 is highly expressed in GH‐producing pituitary adenomas and NFPAs. Direct sequencing showed that two synonymous mutations in exon 2 (87 C > T and 414 C > T) were detected in 4 out of 51 pituitary tumours.

Conclusion  Our results indicate that an activating mutation of the CXCR4 may not be a common pathogenetic mechanism in GH‐producing pituitary tumours and NFPAs.
Assessment of serum‐free cortisol levels in patients with adrenocortical carcinoma treated with mitotane: a pilot study
Authors: Alexandraki Krystallenia I. , Kaltsas Gregory A. , Le Roux Carel W. , Fassnacht Martin , Ajodha Sharon , Christ‐Crain Mirjam , Akker Scott A. , Drake William M. , Edwards Ray , Allolio Bruno , Grossman Ashley B.
Published: May 2009

Objective  Mitotane treatment in adrenocortical carcinoma (ACC) results in unreliable measurement of serum total cortisol (TC) levels because of an elevation in corticosteroid‐binding globulin (CBG).

Design  The use of a newly‐developed serum‐free cortisol (FC) assay was assessed to investigate the characteristics of a more valid measure of cortisol status.

Patients  Sixty‐two serum samples from patients with ACC treated with mitotane were studied. Different subgroups were studied according to mitotane levels (<14, 14–20 and >20 mg/dl), hydrocortisone replacement treatment, presence of Cushing’s syndrome (CS) and adrenocorticotrophin (ACTH) levels.

Measurements  Serum FC was measured using a newly‐developed assay, TC, CBG and plasma ACTH using conventional laboratory kits; TC‐to‐CBG (Free cortisol index, FCI, nmol/mg) and TC‐to‐FC (TFR) ratios were calculated.

Results  CBG levels were elevated and positively correlated to mitotane levels. FC was positively related to TC and FCI in nearly all subgroups studied. Plasma ACTH was negatively related to parameters of cortisol levels in the total samples studied. In the ‘target’ subgroup with normal ACTH levels and mitotane levels 14–20 mg/dl, no correlation of plasma ACTH with any parameter studied was seen, and FC suggested over‐replacement with hydrocortisone treatment in the subgroup with CS.

Conclusions  FC measurement may offer additional information in the follow‐up of patients on mitotane, especially when there is a history of CS which invalidates the use of acute changes in plasma ACTH as a parameter of hydrocortisone replacement. These preliminary data suggest that it may prove useful as a biochemical marker when TC or FCI are invalidated by mitotane treatment or plasma ACTH is suppressed by hypercortisolaemia. Larger studies are needed to substantiate the clinical utility of FC measurement in specific groups of patients.
Effect of sex steroid use on cardiovascular risk in transsexual individuals: a systematic review and meta‐analyses
Authors: Elamin Mohamed B. , Garcia Magaly Zumaeta , Murad Mohammad Hassan , Erwin Patricia J. , Montori Victor M.
Published: May 2009

Objective  To summarize the available evidence on the cardiovascular effects of cross‐sex steroid use in transsexuals.

Methods  We searched relevant electronic databases and sought additional references from experts. Eligible studies reported on cardiovascular events, venous thromboembolism, blood pressure and fasting serum lipids. Data were extracted in duplicate. We used the random‐effects model to estimate the pooled weighted mean difference (WMD) and 95% confidence intervals (CIs).

Results  We found 16 eligible studies, mostly uncontrolled cohorts of varied follow‐up durations (1471 male‐to‐female (MF) and 651 female‐to‐male (FM) individuals). In the MF individuals, cross‐sex hormone use was associated with a statistically significant increase in fasting serum triglycerides without changes in the other parameters (WMD = 23·39 mg/dl; 95% CI = 4·82–41·95). In the FM individuals, there was a similar increase of triglycerides (WMD = 31·35 mg/dl; 95% CI = 7·53–55·17) and a reduction of high density lipoprotein (HDL)‐cholesterol (WMD = −6·09 mg/dl; 95% CI = −11·44 to −0·73). There was a statistically significant but clinically trivial increase in systolic blood pressure (WMD = 1·74 mmHg; 95% CI = 0·21–3·27). Analyses were associated with significant heterogeneity across studies. There were very few reported cardiovascular events (deaths, strokes, myocardial infarctions or venous thromboembolism), more commonly among MF individuals.

Conclusions  Very low quality evidence, downgraded due to methodological limitations of included studies, imprecision and heterogeneity, suggests that cross‐sex hormone therapies increase serum triglycerides in MF and FM and have a trivial effect on HDL‐cholesterol and systolic blood pressure in FM. Data about patient important outcomes are sparse and inconclusive.
Adjuvant effect of LPS and killedPropionibacterium acneson the development of experimental gastrointestinal nematode infestation in sheep
Authors: ABEL L. C. J. , CHEN S. , RICCA L. G. , MARTINS M. F. , GARCIA M. , ANANIAS R. Z. , MUSSALEM J. S. , SQUAIELLA C. C. , SHAW R. J. , LONGO‐MAUGÉRI I. M.
Published: May 2009

Gastrointestinal helminthic infection is an important worldwide sheep disease. The emergence of anthelminthic resistance has led to drives to seek new means of therapeutic control of helminthiasis in sheep. Several data demonstrated the adjuvant effect ofPropionibacterium acneson resistance to infection. Herein, we evaluate the adjuvant effect of the commercial suspension containing LPS andP. acneson experimental helminthiasis. Sheep received three doses of LPS andP. acnescommercial suspension or saline 0·9% (control group). Both groups received orallyHaemonchus contortusinfective larvae on day 0. Parasitological, haematological, lymphoproliferation analysis, IL‐5 and IgE determination were made once a week until 35th day after infection. Our results revealed increase on packed cell volumes on day 14, in LPS + P. acnestreated group. On 21st and 35th days after infection in the same group occurred increase on circulating eosinophils and lymphocytes, and also in the lymphoproliferative response to mitogen. On 35th day, the faecal eggs peak in LPS + P. acnestreated group was significantly lower than control. A negative correlation between faecal eggs counts and circulating eosinophils in the immunostimulant treated group was also observed. Our findings suggest that LPS + P. acnessuspension can be used as a strategy to control helminthiasis in sheep.
Malassezia: is it a pulmonary pathogen in the stem cell transplant population?
Authors: Blaes A.H. , Cavert W.P. , Morrison V.A.
Published: May 2009

Abstract: Malassezia furfur is a yeast that can cause a variety of infections, most commonly in normal hosts, and also in immunocompromised hosts. This yeast typically colonizes the skin, and is the causative agent of tinea versicolor. However, in immunocompromised hosts, it can more commonly cause catheter‐related fungemia or folliculitis. Pulmonary infections from Malassezia have not been commonly recognized. Unlike many other common opportunistic fungal infections in immunocompromised hosts, neutropenia and the use of broad‐spectrum antibiotics do not appear to be significant risk factors for Malassezia infections in the stem cell transplant (SCT) population. Additionally, disseminated infection, despite fungemia, is uncommon. A series of patients who underwent SCT at the University of Minnesota between 2004 and 2006 were reviewed for the occurrence of suspected Malassezia infections in the post‐transplant period. Four cases of possible pulmonary M. furfur infection were identified in our SCT recipients. The clinical characteristics of these patients, the infections, treatment, and outcome are described. In addition, we discuss the possible pathogenicity of this yeast in the pulmonary setting.
A test for Allee effects in the self‐incompatible wasp‐pollinated milkweedGomphocarpus physocarpus
Authors: COOMBS GARETH , PETER CRAIG I. , JOHNSON STEVEN D.
Published: May 2009

It has been suggested that plants that are good colonizers will generally have either an ability to self‐fertilize or a generalist pollination system. This prediction is based on the idea that these reproductive traits should confer resistance to Allee effects in founder populations and was tested usingGomphocarpus physocarpus(Asclepiadoideae: Apocynaceae), a species native to South Africa that is invasive in other parts of the world. We found no significant relationships between the size ofG. physocarpuspopulations and various measures of pollination success (pollen deposition, pollen removal and pollen transfer efficiency) and fruit set. A breeding system experiment showed that plants in a South African population are genetically self‐incompatible and thus obligate outcrossers. Outcrossing is further enhanced by mechanical reconfiguration of removed pollinaria before the pollinia can be deposited. Self‐pollination is reduced when such reconfiguration exceeds the average duration of pollinator visits to a plant. Observations suggest that a wide variety of wasp species in the generaBelonogasterandPolistes(Vespidae) are the primary pollinators. We conclude that efficient pollination of plants in small founding populations, resulting from their generalist wasp‐pollination system, contributes in part to the colonizing success ofG. physocarpus. The presence of similar wasps in other parts of the world has evidently facilitated the expansion of the range of this milkweed.
What is associated with being active in arthritis? Analysis from the Obstacles to Action study
Authors: Hutton I. , Gamble G. , McLean G. , Butcher H. , Gow P. , Dalbeth N.
Published: May 2009

Background: Many adults with arthritis do not achieve physical activity levels recommended for good health. This study aimed to identify factors associated with physical activity participation in people with arthritis.

Methods: 1106 out of 8163 adults with self‐reported arthritis were identified from the 2003 Obstacles to Action study. Participants were classified as active if they reported 30 min of moderate activity ≥5 days a week or 20 min of vigorous activity ≥3 days a week (n = 613), or insufficiently active if they did not (n = 438). Sociodemographic factors, attitudes, self‐efficacy, motivators and barriers to being active were analysed.

Results: Active people with arthritis had a lower burden of chronic disease than insufficiently active people (18% with three or more chronic medical conditions vs 33%, P < 0.0001). Active participants believed more strongly in the benefits of physical activity, reported higher levels of encouragement from others and had greater overall levels of self‐efficacy when compared with the less active participants (P for all <0.0001). Arthritis, fatigue and discomfort were ranked by both groups as the top three barriers. However, the active participants reported lower impact scores for these barriers than the inactive group (P for all <0.0001). These findings persisted after adjusting for occupational status, body mass index and comorbidities.

Conclusion: Active adults with arthritis have lower levels of chronic disease, greater self‐efficacy and fewer psychosocial barriers. Recognition of such barriers and motivators may be useful when designing intervention programmes to help people with arthritis initiate or intensify physical activity participation.
International Reserves and Fiscal Policy in Developing Countries
Authors: Zhou Yan
Published: May 2009

This paper investigates empirically the relationship between the pattern of fiscal policy and the demand for international reserves in developing countries, and how this relationship is associated with political risk and conditional access to global capital markets. It finds evidence that for developing countries with low political risk, countercyclical (procyclical) fiscal policies are associated with higher (lower) international reserve holdings in economic downturns. The relationship is stronger when the countries with low political risk rely heavily on external financing. For developing countries with high political risk, the link between reserves holdings and fiscal policy pattern is not clear‐cut.
How Information Quality of Macro Aggregates Affects Sovereign Risk: An Empirical Investigation
Authors: Lee Seung Jung
Published: May 2009

This paper looks at the relationship between data quality of macro aggregates and the repayment ratio for debt payments due in a given year after a country defaults. We find empirical evidence that good information of macro aggregates reduces sovereign risk by enhancing the repayment ratio conditional on default, while having an insignificant effect on the default probability. The estimation accounts for selection bias by using a cross‐country panel data of 69 developing countries for 1989–2002. Careful consideration is taken to establish information quality of macro aggregates as an exogenous institutional variable. Results are robust to controlling for various governance factors, income levels, and regional factors, etc. Linking information quality to creditors' bargaining power is more consistent with our findings than linking poor information quality to information asymmetry.
Analysing Wage Differences between the USA and Germany Using Proportional Hazards Models
Authors: Behr Andreas , Pötter Ulrich
Published: May 2009

We analyse differences between the wage distributions in the USA and Germany in 2001 for both women and men. The empirical analysis is based on the decomposition of differences using Cox's marginal (partial) likelihood. The approach based on rank invariant estimators such as Cox's is borrowed from the literature on failure time data. Donald et al. pioneered this approach in 2000. However, they did not use the full power of the semi‐parametric approach. Instead, they argued for using a piecewise constant hazard rate model. We improve on their work by showing that the semi‐parametric features of Cox's marginal likelihood are as appropriate for the analysis of wage decompositions and as easy to interpret. Moreover, we extend their approach by allowing for non‐linear regression effects. We show empirically that this formulation both increases the flexibility of their approach and improves the discriminatory power between wage regimes.
Parkinson's Disease and Low Frequency Alleles Found Together Throughout LRRK2
Authors: Paisán‐Ruiz Coro , Washecka Nicole , Nath Priti , Singleton Andrew B. , Corder Elizabeth H.
Published: May 2009

Mutations within LRRK2, most notably p.G2019S, cause Parkinson's disease (PD) in rare monogenic families, and sporadic occurrences in diverse populations. We investigated variation throughout LRRK2 (84 SNPs; genotype or diplotype found for 49 LD blocks) for 275 cases (European ancestry, onset at age 60 or older) and 275 neurologically healthy control subjects (NINDS Neurogenetics Repository). Three grade‐of‐membership groups, i.e. genetic risk sets, were identified that exactly matched many subjects (cases: 46, 4, 137; controls: 0, 178, 0), and distinguished 94% of the subjects (i.e. >50% likeness to one set). Set I, affected, carried certain low frequency alleles located in multiple functional domains. Set II was unaffected. Set III, also affected, resembled set II except for slightly elevated frequencies of minor alleles not defining set I. We conclude that certain low frequency alleles distributed throughout LRRK2 are a genetic background to a third of cases, defining a distinct subset.
Patterns of caudal‐autotomy evolution in lizards
Authors: Zani Peter A.
Published: May 2009

Using comparative techniques to account for phylogenetic effects, I examined patterns of evolution of caudal autotomy and foraging in 39 lizard species to test the hypothesis that caudal autotomy has co‐evolved with morphology, locomotor performance, and foraging behaviour. There were significant positive associations between evolution of the point on the tail (distance from cloaca) at which tail loss occurs (an indirect measure of caudal autotomy) and evolution of each of the following: tail length,caudifemoralis longus(CFL) muscle length, and jump distance. The correlation with the evolution of sprint speed approached significance. These relationships primarily were due to the influence of tail‐length evolution on autotomy‐point evolution. With the effect of tail‐length evolution removed, autotomy‐point evolution was negatively correlated with the evolution of tail‐loss frequency. The CFL restricts tail loss to portions of the tail posterior to the most distal point of its insertion in the tail. In addition, with the effect of tail‐length evolution removed, CFL length co‐evolved with sprint speed. These results indicate that tail morphology has co‐evolved with caudal autotomy such that the evolution of the CFL has reduced caudal autotomy in certain groups of lizards.

Ambush foraging, the ability to lose the tail, intermediate CFL length, and low locomotor performance (i.e. slow sprint speed and short jump distance) are hypothesized to be the ancestral conditions in lizards using outgroup rooting. The diversification of lizard taxa has resulted in some lineages moving away from ancestral character states (i.e. family Teiidae, superfamily Varanoidea), while others are very similar or identical to their ancestors (i.e. superfamily Iguania).
The social structure and dominance hierarchy of the Mashona mole‐rat, Cryptomys darlingi (Rodentia: Bathyergidae) from Zimbabwe
Authors: Gabathuler U. , Bennett N. C. , Jarvis J. U. M.
Published: May 2009

Cryptomys darlingi is a social subterranean rodent mole which inhabits the mesic regions of south‐eastern and central Africa. Mashona mole‐rats live in small colonies (5‐9 animals) in which reproduction is normally restricted to the largest male and female in the colony. The non‐reproductive members in a mature colony cannot be placed into clearly defined work‐related groups based on body mass.

The dominance hierarchy of a young colony was found to be linear, with a value of 1.00 calculated from Landau's linearity index, while that of a mature colony of nine mole‐rats was almost linear (0.77). Dominance was found to be related to gender in the mature colony, with males more dominant than females, and to age in the young colony. The reproductive mole‐rats are the dominant animals within their respective genders. Dominance appears to correlate positively with body mass (rs = 0.77 in the mature colony and rs = 0.93 in the young colony).

Popularity studies show that smaller animals and females tend to be more popular than the larger massed individuals or males. In the mature colony which contained predominantly adult animals, the reproductive pair was among the least popular. While in the young colony, composed predominantly of sub‐adult and juvenile animals, the reproductive pair was the most popular.

Social organization within Mashona mole‐rat colonies is compared with other southern African Cryptomys species.
Reproduction in the round‐eared elephant shrew (Macroscelides proboscideus) in the southern Karoo, South Africa
Authors: Bernard R. T. F. , Kerley G. I. H. , Doubell T. , Davison A.
Published: May 2009

Reproduction in round‐eared elephant shrews occurred throughout the year. Male round‐eared elephant shrews were spermatogenically active, with spermatozoa stored in the cauda epididymes, throughout the year. Pregnant females occurred in all months except March and May and there was a decline in the occurrence of pregnancies during early winter (March‐July). This tendency towards seasonality of pregnancies was mirrored by the appearance of juveniles, with 77% of all young animals caught between September and February. Bone calcium concentrations were significantly lower during the dry winter than during summer. From October onwards (the beginning of the wet season), bone calcium concentrations increased, reaching high levels in December which were maintained until April. This increase in bone calcium concentrations coincided with the rainy season and with an increase in the intake of herbage, and during this period 60% of all pregnancies occurred. We conclude that the ability of the round‐eared elephant shrew to vary its diet may allow some individuals to breed throughout the year. The reduction in the occurrence of pregnancies in early winter probably ensures that few births occur when bone calcium concentrations are low.
Arm joint articulations in the ophiuran brittlestars (Echinodermata: Ophiuroidea): a morphometric analysis of ontogenetic, serial, and interspecific variation
Authors: LeClair Elizabeth E.
Published: May 2009

The ophiuroid arm contains a series of vertebral ossicles that form an articulated internal skeleton. Ontogenetic, serial, and interspecific variation in these skeletal elements are investigated using morphometric data from 35 species of brittle‐stars (Order Ophiurae). Multiple ossicles were sampled from each individual and several individuals were sampled from each species to reconstruct serial and ontogenetic changes in vertebral morphology. Within species, ontogenetic and serial allometries are not statistically different. These data support ‘Jackson's law of localized stages’ (Jackson, 1899; Clark, 1914), which proposes that serial variation along the arm reflects ontogenetic stages of ossicle growth.

A multivariate analysis of interspecific variation shows two major vertebral forms: ossicles with a proximal depression and distal keel, and ossicles lacking these features. Variation within these groups is largely continuous, but individual species show distinct shape differences and unique allometric patterns of serial variation. These results suggest that vertebral ossicle variation among species can be described by: 1) variation in initial shape; and 2) variation in the allometric trajectory along the proximal‐distal axis.

In all species, the most proximal ossicles within the disk show a non‐keeled morphology. In species with keeled arm ossicles, however, there is an abrupt transition within the disk between non‐keeled and keeled vertebral forms. A single ossicle, having features of both vertebral types, occurs at this site. The taxonomic distribution of the two vertebral forms and the anatomical transition between forms is discussed with reference to current classification systems and recent phylogenetic schemes for the Ophiuroidea.
Diet of the maned wolf, Chrysocyon brachyurus, in central Brazil
Authors: Motta‐Junior J. C. , Talamoni S. A. , Lombardi J. A. , Simokomaki K.
Published: May 2009

Analysis of 105 scats of the maned wolf (Chrysocyon brachyurus) collected in central Brazil yielded 304 occurrences of food items of which fruits of Solanum lycocarpum, rodents, and birds accounted for 61.5%. By analysis of minimum number of individual animals, rodents and birds were 75% of a total of 156 prey. On the other hand, fruits of S. lycocarpum and armadillos (Dasypus spp.) were the bulk of the total estimated biomass consumption, yielding 63.7% in a total of 73.5 kg. Rodents were mostly captured during the dry season, while miscellaneous fruits were consumed mostly in the wet season. The consumption of S. lycocarpum fruits and armadillos was aseasonal. Small rodents were taken in about the ranks of abundance in the study area, but S. lycocarpum fruits were actively searched by maned wolves, for its occurrence is limited to secondary savanna. Prey and fruits typical of savanna (‘cerrado’) and grassland (‘campo’) were the bulk of species, occurrences, prey numbers, and biomass consumed. These findings reinforce the importance of conservation of cerrado and campo in central Brazil. Despite maned wolf being a vulnerable species, its feeding habits are opportunistic, and the main reasons for its decline are likely to be habitat destruction and human disturbance.
The relative densities of red (Cervus elaphus) and roe (Capreolus capreolus) deer and their relationship in Scottish plantation forests
Authors: Latham J. , Staines B. W. , Gorman M. L.
Published: May 2009

Population densities of red and roe deer were estimated in 20 conifer plantations throughout central and northern Scotland. Ten forests were selected on the basis of culling records that were considered likely to cover the range of possible densities. Ten further forests were selected at random to investigate the relationship between red and roe deer densities. Density assessment was by standing‐crop dung‐group counts, on 1.5 x 100 m transects. Dung decay rates were estimated in four areas and used to convert the values to deer densities. Red deer densities were estimated to range from 0.3‐35 km−2; roe deer densities ranged from 0.5‐25 km−2. Preferences for different structural habitats within individual forests (i.e. blocks with different age classes of tree) were inferred from dung densities. Red deer preferred unplanted ground, open‐thicket, and prethicket; roe deer likewise preferred prethicket (highly) and open‐thicket. Both species avoided closed‐canopy habitats. Red and roe deer densities were negatively correlated and the relationship was significant when the data were log transformed (P < 0.05).
Is flight architecture determined by physical constraints or by natural selection?: the case of the midge Chironomus plumosus
Authors: McLachlan A. J. , Neems R. M.
Published: May 2009

Males of the midge Chironomus plumosus fly solely to mate. They maintain station for long periods in moving air. Females patrol in search of males and, after receiving a spermatophore, fly to oviposition sites. The requirements of flight in males and females are therefore fundamentally different. Females are larger than males, on average, so these differences could stem from scaling rules governing the geometry of space. The same explanation might apply to flight differences within the sexes and even to peculiarities of flight architecture in C. plumosus compared to other flying animals. In other words, might flight design be accounted for entirely by mechanical constraints without recourse to natural selection?

To test this hypothesis, the power output of C. plumosu was measured as size‐specific muscle mass. Contrary to expectation, little evidence was found of scaling effects in this measure of power. Despite its being among the smallest of animals to fly, C. plumosus turns out to have the largest mass of flight muscle, relative to body size, yet found among animals. Differences both between C. plumosus and other species and within C. plumosus are, in general, more readily accounted for by the requirements of the mating system within the viscous universe encountered by small flying animals. We conclude that it is natural selection rather than mechanical constraint that is the primary influence determining the architecture of flight in this small animal.
Rate of metabolism, temperature regulations, and evaporative water loss in the lesser gymnure Hylomys suillus (Insectivora, Mammalia)
Authors: Genoud M. , Ruedi M.
Published: May 2009

Rate of metabolism, body temperature, wet thermal conductance, and evaporative water loss were measured at different ambient temperatures in four lesser gymnures Hylomys suillus. Gymnures responded as typical endothermic homoiotherms to changes in ambient temperature. Below the lower critical temperature of 32°C, they maintained a body temperature of 37.3± 0.3°C by an increased rate of metabolism. Minimum wet thermal conductance was 111% of that expected on the basis of body mass. Average basal rate of metabolism was 1.04 ml O2 g−1 h−1, which represents 106% of the expected value. Within and above the thermoneutral zone, heat loss by evaporation did not account for more than 30% of the heat produced. As a consequence, the body temperature of gymnures was maintained 4°C above ambient temperature. These metabolic and thermoregulatory patterns differ strikingly from those of other members of the family Erinaceidac and can be interpreted as a result of physiological adaptation to a different ecology. Being smaller than hedgehogs and inhabiting montane tropical rainforests, lesser gymnures lack the physiological traits which enable many hedgehogs to invade hot, arid and/or strongly seasonal environments.
Habitat selection by European beaver (Castor fiber) colonizing a boreal landscape
Authors: Hartman Göran
Published: May 2009

The beaver, exterminated in Sweden in the 19th century, was reintroduced in the 1920s. The population is still increasing its range and individuals at the expansion front can still move into optimal habitats. Therefore, there is no need for beavers to occupy marginal habitats, and preferred habitats are not yet altered by the beavers themselves. Salient features of occupied and unoccupied habitats were analysed by partial least square projections to latent structures (PLS) in order to identify the important factors. The tortuosity of streams, and occurrence of grasses and forbs in the ground layer, had the strongest positive effects. Availability of deciduous forest differed univariately between used and unused sites, but added little to the model. It is suggested that variables describing geomorphological stages in stream development will increase both the general applicability and reliability of studies that attempt to assess the quality of beaver habitat.
Sexual dimorphism, reproductive biology, and food habits of two species of African filesnakes (Mehelya, Colubridae)
Authors: Shine R. , Branch W. R. , Harlow P. S. , Webb J. K.
Published: May 2009

The ecology and general biology of African snakes remains virtually unstudied, even in highly distinctive species such as the filesnakes (genera Mehelya and Gonionotophis). Our measurements and dissections of preserved specimens provided information on body sizes, sexual dimorphism in size and bodily proportions, clutch sizes, and food habits of two Mehelya species. In both M. capensis and M. nyassae, females attain sexual maturity at the same size as conspecific males, but grow to much larger sizes. Mehelya capensis displays extreme differences in body shape between males and females at the same body length: females have longer and wider heads, thicker bodies, and larger eyes (relative to both head length and head width) than do conspecific males. Dimorphism in body proportions is less marked in M. nyassae. Female reproductive cycles are seasonal in M. capensis, and clutch sizes are larger in this species than in its smaller congener (5‐11 eggs in M. capensis, 2‐6 eggs in M. nyassae).

Contrary to popular wisdom, Mehelya are not specialized ophiophages. Mehelya nyassae feeds primarily upon lygosomatine skinks, including many fossorial taxa. Mehelya capensis has a broader diet, feeding on a wide variety of terrestrial lizards (especially agamids and gerrhosaurids) and snakes. Toads are also common prey items. The diversity of prey types taken by M. capensis suggests that these snakes may use ambush predation as well as active foraging. Mehelya is strongly convergent with Asian elapids of the genus Bungarus in its morphology (triangular body shape; powerful jaws; visible interstitial skin), behaviour (nocturnality; reluctance to bite when harassed), and diet (feeding on elongate reptiles, including snakes). Observations of preyhandling and ingestion by captive snakes are needed to clarify possible selective forces for the evolution of the unusual traits shared by these taxa.
Two new species of freshwater Oligochaeta from the North‐west Iberian Peninsula: Krenedrilus realis sp. nov. (Tubificidae) and Cernosvitoviella bulboducta sp. nov. (Enchytraeidae)
Authors: Martínez‐Ansemil E. , Collado R.
Published: May 2009

Two new species of aquatic Oligochaeta are described from the North‐west Iberian Peninsula: Krenedrilus realissp. nov. (Tubificidae) and Cernosvitoviella bulboductasp. nov. (Enchytraeidae). Krenedrilus realis is the fourth species in a genus of small and presumably plesiomorphic Tubificinae. It is closely related to K. sergei Giani, Erséus & Martínez‐Ansemil, 1990. Cernosvitoviella bulboducta belongs to a genus of small amphibiotic enchytraeids. It is close to C. ampullax Klungland & Abrahamsen, 1981 and C. tatrensis (Kowalewski, 1916). Supplementary data to the diagnosis of C. tatrensis are given. The presence of two small glands attached to the gut immediately behind the pharyngeal bulb is noticed in C. bulboducta and C. tatrensis. This previously unknown character is probably more common in the genus than has been supposed.
Redescription of the Central American electric fish Gymnotus cylindricus (Ostariophysi: Gymnotiformes: Gymnotidae), with comments on character ambiguity within the ostariophysan clade
Authors: Campos‐da‐Paz Ricardo
Published: May 2009

Gymnotus cylindricus LaMonte, a poorly studied Central American electric fish primarily observed in the Rio Motagua basin (Guatemala) and north‐western Honduras, is redescribed in detail. A clear diagnosis of this species is provided, with new information on overall morphology, osteology, and colour pattern. In a separate section, comments on character ambiguity within the Ostariophysi are made, which led to a reinterpretation of seven homoplastic characters proposed by Fink & Fink (1981) in their work on interrelationships among five major lineages of the superorder. Although the topology of their cladogram remains unchanged, the present view is that alternative explanations regarding evolution of those characters are possible, and the new ones here offered agree with initial hypotheses of primary homologies.
Seasonal metabolism of a small, arboreal monitor lizard, Varanus scalaris, in tropical Australia
Authors: Christian K. , Green B. , Bedford G. , Newgrain K.
Published: May 2009

The field metabolic rates (FMR) and water fluxes of Varanus scalaris were measured during the wet and dry seasons by the doubly‐labelled water technique. Seasonal measurements of standard (night‐time) metabolism (SMR) and resting (daytime) metabolism (RMR) were made in the laboratory at 18, 24, 30 and 36°C, and maximal oxygen consumption was measured at 36°C on a motorized treadmill. This population was active throughout the year. In the wet season, the mean FMR was 7.8 kJ day−1 (128.0 kJkg−1 day−1; mean mass = 66.4 g, n= 13), and during the dry season the mean was 5.0 kJ day−1 (67.6 kJ kg−1 day−1; mean mass = 77.4 g, n= 17). The mean water flux rates for these animals were 3.6 and 1.2 ml day−1, respectively (60.4 and 16.6 ml kg−1 day−1). The seasonal means of FMR and water flux were significantly different by ANCOVA (P < 0.0001). Measurements of SMR and RMR were significantly higher in the wet season (ANCOVA: P < 0.0001), but we found no difference in the maximal oxygen consumption between seasons (ANCOVA: P= 0.6). The maximal oxygen consumption of the lizards on the treadmill (2.9 ml min−1= 1.8 ml g−1 h−1), mean mass = 97.4 g, n= 16) was 20 times that of the SMR at the same temperature during the dry season, and 11 times that of the SMR during the wet season. The seasonal differences in FMR were attributable to: changes in SMR (12.2%) and RMR (16.4%); differences in night‐time body temperatures (11.3) and daytime body temperatures (16.4%); and activity (broadly defined to include locomotion, digestion, and reproductive costs (43.7%).
Nicotinamide enhances mitochondria quality through autophagy activation in human cells
Authors: Kang Hyun Tae , Hwang Eun Seong
Published: May 2009

Nicotinamide (NAM) treatment causes a decrease in mitochondrial respiration and reactive oxygen species production in primary human fibroblasts and extends their replicative lifespan. In the current study, it is reported that NAM treatment induces a decrease in mitochondrial mass and an increase in membrane potential (ΔΨm) by accelerating autophagic degradation of mitochondria. In the NAM‐treated cells, the level of LC3‐II as well as the number of LC3 puncta and lysosomes co‐localizing with mitochondria substantially increased. Furthermore, in the NAM‐treated cells, the levels of Fis1, Drp1, and Mfn1, proteins that regulate mitochondrial fission and fusion, increased and mitochondria experienced dramatic changes in structure from filaments to dots or rings. This structural change is required for the decrease of mitochondrial mass indicating that NAM accelerates mitochondrial autophagy, at least in part, by inducing mitochondrial fragmentation. The decrease in mitochondria mass was attenuated by treatment with cyclosporine A, which prevents the loss of mitochondrial membrane potential by blocking the mitochondrial permeability transition, suggesting autophagic degradation selective for mitochondria with low ΔΨm. All these changes were accompanied by and dependent on an increase in the levels of GAPDH, and are blocked by inhibition of the cellular conversion of NAM to NAD+. Taken together with our previous findings, these results suggest that up‐regulation of GAPDH activity may prolong healthy lifespan of human cells through autophagy‐mediated mitochondria quality maintenance.
Radiation sensitivity increases with proliferation‐associated telomere dysfunction in nontransformed human epithelial cells
Authors: Soler David , Pampalona Judit , Tusell Laura , Genescà Anna
Published: May 2009

Epidemiological studies have demonstrated age differences among human adults in susceptibility to radiation, with cancer cases attributable to radiation being more frequent for older individuals at time of exposure. In addition to the notion that susceptibility increases because of progressive decline in DNA monitoring and immunosurveillance, telomere function is now emerging as a new and important factor in modulating cellular and organism sensitivity to ionizing radiation. The link between telomeres and radiosensitivity is well‐documented in humans, but the causal events remain elusive. In this paper, it is shown that irradiated human epithelial cells with short dysfunctional telomeres derived from normal mammary gland display elevated DNA damage. An approach identifying the specific chromosomes with critically shortened telomeres in each donor has allowed us to conclude that short dysfunctional telomeres in human epithelial cells join radiation‐induced DNA broken ends, thus interfering with their efficient repair. These findings argue against telomeres participating as sensors or transducers of DNA damage, as previously suggested. Rather, our current findings give support to the idea that dysfunctional telomeres, by acting as an additional joining option, reduce the repair fidelity of DNA broken‐ends induced by radiation throughout the genome. In the mammary gland, age‐dependent telomere attrition due to epithelial turnover, together with the accretion of checkpoint deficiencies, might render the accumulation of short dysfunctional telomeres. This implies that the risks associated with mammography screening could be higher than previously assumed. Our results have the possibility of imprinting a temporal dimension onto radiation sensitivity, namely, that shortened telomeres in aged cells may more easily compromise normal tissue function in the elderly.
Fibrin sealant combined with fibroblasts and platelet‐derived growth factor enhance wound healing in excisional wounds
Authors: Mogford Jon E. , Tawil Bill , Jia Shengxian , Mustoe Thomas A.
Published: May 2009

We test the hypothesis that the fibrinogen‐thrombin formulation of fibrin sealant combined with fibroblasts and PDGF‐BB enhance cutaneous wound healing. Four formulations varying in fibrinogen and thrombin concentration were applied to full‐thickness biopsy wounds in the rabbit ear cutaneous wound healing model with or without cultured rabbit dermal fibroblasts (RDFs; 3 × 105 cells/wound) embedded in the fibrinogen component. At post‐wounding day 7, there was no difference in the diluted vs. non‐diluted formulations for either the promotion of granulation tissue coverage of the open wounds or total granulation tissue area when tested without embedded cells. Including the RDFs, the highest degree of wound coverage by granulation tissue was observed in the combined dilution formulation (17.3 mg/mL fibrinogen, 167 U/mL thrombin; n=10 wounds) that was 167% (p<0.05) of the nondiluted FS containing cells (50 mg/mL fibrinogen, 250 U/mL thrombin; n=10 wounds). Inclusion of fibroblasts increased granulation tissue area within the wounds vs. FS alone (p<0.05) for each diluted formulation although no differences in this parameter were observed within each group (FS alone or with embedded cells). However, addition of the vulnerary growth factor PDGF‐BB (3 mg; n=4) with the embedded RDFs in the combined dilution formulation increased granulation tissue area over two‐fold (p<0.01) over FS alone. Additionally, the presence of the RDFs promoted incorporation of the granulation tissue with and epithelial migration over the FS suggesting an active interaction between cells delivered to the wound by FS and the host repair cells. The findings suggest the progress of cutaneous defect repair can be enhanced by ex vivo cell delivery in fibrin sealant.
A combination of curcumin and ginger extract improves abrasion wound healing in corticosteroid‐impaired hairless rat skin
Authors: Bhagavathula Narasimharao , Warner Roscoe L. , DaSilva Marissa , McClintock Shannon D. , Barron Adam , Aslam Muhammad N. , Johnson Kent J. , Varani James
Published: May 2009

Hairless rats were topically treated with a combination of 10% curcumin and 3% ginger extract (or with each agent alone) for a 21‐day period. Following this, the rats were treated topically with Temovate (corticosteroid) for an additional 15 days. At the end of the treatment period, superficial abrasion wounds were induced in the treated skin. Abrasion wounds healed more slowly in the skin of Temovate‐treated rats than in skin of control animals. Healing was more rapid in skin of rats that had been pretreated with either curcumin or ginger extract alone or with the combination of curcumin–ginger extract (along with Temovate) than in the skin of rats treated with Temovate and vehicle alone. Skin samples were obtained at the time of wound closure. Collagen production was increased and matrix metalloproteinase‐9 production was decreased in the recently healed skin from rats treated with the botanical preparation relative to rats treated with Temovate plus vehicle. In none of the rats was there any indication of skin irritation during the treatment phase or during wounding and repair. Taken together, these data suggest that a combination of curcumin and ginger extract might provide a novel approach to improving structure and function in skin and, concomitantly, reducing formation of nonhealing wounds in “at‐risk” skin.
Does cowbird parasitism increase predation risk to American redstart nests?
Authors: Hannon Susan J. , Wilson Scott , McCallum Cindy A.
Published: May 2009

Brood parasitism and nest predation are major causes of reproductive failure for many bird species nesting in fragmented landscapes. While brood parasites and predators may act independently, they could also interact if brood parasites increase the likelihood that predators detect nests. In this study, we examined the interaction between cowbird parasitism and nest predation in a 10 year study on 466 American redstart Setophaga ruticilla nests in central Alberta, Canada. We used advanced nest survival models to examine the support for three mechanisms that might lead to a positive correlation between brood parasitism and nest predation: 1) the presence of a cowbird nestling might increase the detection of the nest by predators, 2) nests with lower cover are more likely to be detected by both cowbirds and predators, and 3) cowbirds and predators may co‐occur in landscapes of similar structure. Twelve percent of nests were parasitized and those nests had a 16–19% higher rate of failure due to predators compared to unparasitized nests. Daily nest predation rates increased during the nestling stage for both groups, but more strongly for parasitized nests. Loud begging by the cowbird nestling and/or higher parental feeding rates for the cowbird may have increased nest detectability to predators. Brood parasitism and nest predation were also positively related to forest cover, indicating landscape level effects were influential. Most nest predators were forest species and we suspect cowbirds responded positively to forest cover because of the increased abundance of songbird hosts. Nest‐site features had less of an impact on nest predation or brood parasitism, although nests with higher overhead cover were less susceptible to predators. Our study shows how multiple mechanisms, particularly the behavioral effects of the brood parasite nestling and landscape structure, can lead to a positive relationship between nest predation and brood parasitism.