bluuebunny/crossref_metadata_2025_split huggingface dataset:
Changes in the central component of the hypothalamus-pituitary-thyroid axis in a rabbit model of prolonged critical illness
Authors: Mebis Liese , Debaveye Yves , Ellger Björn , Derde Sarah , Ververs Eric-Jan , Langouche Lies , Darras Veerle M , Fliers Eric , Visser Theo J , Van den Berghe Greet 
Published: September 2009

Abstract
Introduction
Prolonged critically ill patients reveal low circulating thyroid hormone levels without a rise in thyroid stimulating hormone (TSH). This condition is labeled "low 3,5,3'-tri-iodothyronine (T3) syndrome" or "nonthyroidal illness syndrome (NTI)" or "euthyroid sick syndrome". Despite the low circulating and peripheral tissue thyroid hormone levels, thyrotropin releasing hormone (TRH) expression in the hypothalamus is reduced and it remains unclear which mechanism is responsible. We set out to study whether increased hypothalamic T3 availability could reflect local thyrotoxicosis and explain feedback inhibition-induced suppression of the TRH gene in the context of the low T3 syndrome in prolonged critical illness.

Methods
Healthy rabbits were compared with prolonged critically ill, parenterally fed animals. We visualized TRH mRNA in the hypothalamus by in situ-hybridization and measured mRNA levels for the type II iodothyronine diodinase (D2), the thyroid hormone transporters monocarboxylate transporter (MCT) 8, MCT10 and organic anion co-transporting polypeptide 1C1 (OATP1C1) and the thyroid hormone receptors α (TRα) and β (TRβ) in the hypothalamus. We also measured the activity of the D2 and type III iodothyronine deiodinase (D3) enzymes.

Results
In the hypothalamus of prolonged critically ill rabbits with low circulating T3 and TSH, we observed decreased TRH mRNA, increased D2 mRNA and increased MCT10 and OATP1C1 mRNA while MCT8 gene expression was unaltered as compared with healthy controls. This coincided with low hypothalamic thyroxine (T4) and low-normal T3 concentrations, without a change at the thyroid hormone receptor level.

Conclusions
Although expression of D2 and of the thyroid hormone transporters MCT10 and OATP1C1 were increased in the hypothalamus of prolonged critical ill animals, hypothalamic T4 and T3 content or thyroid hormone receptor expression were not elevated. Hence, decreased TRH gene expression, and hereby low TSH and T3 during prolonged critical illness, is not exclusively brought about by hypothalamic thyrotoxicosis, and infer other TRH suppressing factors to play a role.
De novo genome sequence assembly of a filamentous fungus using Sanger, 454 and Illumina sequence data
Authors: DiGuistini Scott , Liao Nancy Y , Platt Darren , Robertson Gordon , Seidel Michael , Chan Simon K , Docking T Roderick , Birol Inanc , Holt Robert A , Hirst Martin , Mardis Elaine , Marra Marco A , Hamelin Richard C , Bohlmann Jörg , Breuil Colette , Jones Steven JM 
Published: September 2009

AbstractSequencing-by-synthesis technologies can reduce the cost of generating de novo genome assemblies. We report a method for assembling draft genome sequences of eukaryotic organisms that integrates sequence information from different sources, and demonstrate its effectiveness by assembling an approximately 32.5 Mb draft genome sequence for the forest pathogen Grosmannia clavigera, an ascomycete fungus. We also developed a method for assessing draft assemblies using Illumina paired end read data and demonstrate how we are using it to guide future sequence finishing. Our results demonstrate that eukaryotic genome sequences can be accurately assembled by combining Illumina, 454 and Sanger sequence data.
ABC drug transporters and immunity: novel therapeutic targets in autoimmunity and cancer
Authors: van de Ven Rieneke , Oerlemans Ruud , van der Heijden Joost W , Scheffer George L , de Gruijl Tanja D , Jansen Gerrit , Scheper Rik J 
Published: September 2009

AbstractReview evaluates the possible physiological roles of MDR-related ABC transporters on immune effector cells based on reports on their expression patterns and immune-related substrates.ABC transporters were identified originally for their contribution to clinical MDR as a result of their capacity to extrude various unrelated cytotoxic drugs. More recent reports have shown that ABC transporters can play important roles in the development, differentiation, and maturation of immune cells and are involved in migration of immune effector cells to sites of inflammation. Many of the currently identified, endogenous ABC transporter substrates have immunostimulating effects. Increasing the expression of ABC transporters on immune cells and thereby enhancing immune cell development or functionality may be beneficial to immunotherapy in the field of oncology. On the contrary, in the treatment of autoimmune diseases, blockade of these transporters may prove beneficial, as it could dampen disease activity by compromising immune effector cell functions. This review will focus on the expression, regulation, and substrate specificity of ABC transporters in relation to functional activities of immune effector cells and discusses implications for the treatment of cancer on the one hand and autoimmune diseases on the other.
Flexible clap and fling in tiny insect flight
Authors: Miller Laura A. , Peskin Charles S. 
Published: September 2009

SUMMARYOf the insects that have been filmed in flight, those that are 1 mm in length or less often clap their wings together at the end of each upstroke and fling them apart at the beginning of each downstroke. This `clap and fling'motion is thought to augment the lift forces generated during flight. What has not been highlighted in previous work is that very large forces are required to clap the wings together and to fling the wings apart at the low Reynolds numbers relevant to these tiny insects. In this paper, we use the immersed boundary method to simulate clap and fling in rigid and flexible wings. We find that the drag forces generated during fling with rigid wings can be up to 10 times larger than what would be produced without the effects of wing–wing interaction. As the horizontal components of the forces generated during the end of the upstroke and beginning of the downstroke cancel as a result of the motion of the two wings, these forces cannot be used to generate thrust. As a result, clap and fling appears to be rather inefficient for the smallest flying insects. We also add flexibility to the wings and find that the maximum drag force generated during the fling can be reduced by about 50%. In some instances, the net lift forces generated are also improved relative to the rigid wing case.
Oxygen tension correlates with regional blood flow in obstructed rat kidney
Authors: Jensen Anja M. , Nørregaard Rikke , Topcu Sukru Oguzkan , Frøkiær Jørgen , Pedersen Michael 
Published: September 2009

SUMMARYAs renal tissue oxygen tension (PO2) is determined by the balance between oxygen supply and consumption, direct tissue PO2 measurements are essential when evaluating the presence of hypoxia. The present study aimed at evaluating invasively and continuously the renal medullary and cortical tissue PO2 by novel fibre-optic probes in rats subjected to acute unilateral ureteral obstruction (AUUO). In parallel,regional blood flow measurements were obtained by MRI to investigate the relationship between regional blood flow and tissue oxygen tension. The abundance of transport proteins was determined by immunoblotting. In the obstructed kidney, AUUO caused a prompt decrease in medullary tissue PO2 to 60% of baseline level whereas cortical tissue PO2 was unchanged. By contrast, tissue PO2 slightly increased in the non-obstructed kidney. These changes developed during the first 30 min after AUUO and persisted for the 3 h observation period. Medullary blood flow declined 1.5–2 h after induction of AUUO to 61% of baseline level in the obstructed kidney. By contrast, cortical blood flow increased to 108% of baseline level in the non-obstructed kidney. Finally, the abundance of phosphorylated aquaporin 2 decreased significantly in the obstructed kidney medulla, but increased in the obstructed kidney cortex. The Na+/K+-ATPase abundance increased in the obstructed kidney medulla whereas the Na+/K+/2Cl–co-transporter abundance remained unchanged in the obstructed kidney. In conclusion, measurements of regional blood flow reflect tissue PO2 changes during AUUO suggesting that reduced regional blood flow is a predictor of local hypoxia. Furthermore, the abundance of major transport protein is independent of tissue PO2.
Food restriction in young Japanese quails: effects on growth, metabolism,plasma thyroid hormones and mRNA species in the thyroid hormone signalling pathway
Authors: Rønning Bernt , Mortensen Anne S. , Moe Børge , Chastel Olivier , Arukwe Augustine , Bech Claus 
Published: September 2009

SUMMARYYoung birds, in their post-natal growth period, may reduce their growth and metabolism when facing a food shortage. To examine how such responses can be mediated by endocrine-related factors, we exposed Japanese quail chicks to food restriction for either 2 days (age 6–8 days) or 5 days (age 6–11 days). We then measured growth and resting metabolic rate (RMR),and circulating 3,3′,5-triiodo-l-thyronine (T3) and 3,5,3′,5′-tetraiodothyronine (T4) levels as well as expression patterns of genes involved in growth (insulin-like growth factor-I: IGF-I) and thyroid hormone signalling (thyroid-stimulating hormone-β: TSHβ,type II iodothyronine deiodinase: D2, thyroid hormone receptors isoforms:TRα and TRβ). The food-restricted chicks receiving a weight-maintenance diet showed reductions in structural growth and RMR. Plasma levels of both T3 and T4 were reduced in the food-restricted birds, and within the 5 days food-restricted group there was a positive correlation between RMR and T3. IGF-I mRNA showed significantly higher abundance in the liver of ad libitum fed birds at day 8 compared with food-restricted birds. In the brain, TSHβ mRNA level tended to be lower in food-restricted quails on day 8 compared with controls. Furthermore, TRα expression was lower in the brain of food-restricted birds at day 8 compared with birds fed ad libitum. Interestingly, brain D2 mRNA was negatively correlated with plasma T3 levels, tending to increase with the length of food restriction. Overall, our results show that food restriction produced significant effects on circulating thyroid hormones and differentially affected mRNA species in the thyroid hormone signalling pathway. Thus, we conclude that the effects of food restriction observed on growth and metabolism were partly mediated by changes in the endocrine-related factors investigated.
Evidence for age-dependent mating strategies in the simultaneous hermaphrodite snail,Lymnaea stagnalis(L.)
Authors: Hermann Petra M. , Genereux Brad , Wildering Willem C. 
Published: September 2009

SUMMARYIn many mating systems female reproductive capacity is a limiting resource over which males will compete. As a consequence, males and females have usually different fitness optimization strategies which may give rise to sexual conflict. Since simultaneous hermaphrodites have, in theory, the option to mate as male or as female at any time, conflict will occur if partners insist in taking the same role. Several lines of evidence exists that body size influences gender choice. However, growth in many invertebrates is indeterminate and therefore age is generally a covariant of size. We therefore investigated the effect of age on mating choices in the simultaneous hermaphrodite Lymnaea stagnalis. Using fully sexually mature animals sampled from three different age groups we show that copulation frequency declines with age. Specifically, in age-matched couples the frequency of primary and reciprocal copulations declines with age. Furthermore, the younger partner tends to mate as male with greater probability in couples of unequal age. Size was never a factor in the sex role preference of Lymnaea. Thus, young Lymnaea always attempt to copulate as male independent of the age of their partner, whereas senior snails act primarily as female. The sex role choices of middle-aged snails appear to depend on their partner's age. In addition, we demonstrate that the likelihood that an animal will copulate as male is not correlated with prostate gland size but correlates with the level of afferent electrical activity recorded in the nerve originating in the prostate gland. Together, our results indicate the existence of an age- and not size-dependent mating system in Lymnaea.
Effects of temperature and dietary sterol availability on growth and cholesterol allocation of the aquatic keystone speciesDaphnia
Authors: Sperfeld Erik , Wacker Alexander 
Published: September 2009

SUMMARYEnhanced water temperatures promote the occurrence of cyanobacterial blooms, which may be detrimental to aquatic herbivores. Especially, the often-dominant crustaceans could be negatively affected because cyanobacteria are deficient in phytosterols, which are required by the crustaceans to form the membrane component cholesterol, which in turn plays a role in thermal adaptation. Here, we determined the influence of temperature on growth,reproduction and the allocation of dietary sterol into somatic tissues and eggs of the keystone species Daphnia magna raised along a dietary cholesterol gradient. Mass-specific growth rates of D. magnaincreased with the increasing availability of dietary cholesterol up to an incipient limiting level, which increased with increasing temperature. This indicates a higher demand for cholesterol for growth at higher temperatures and may explain the consistently smaller clutch sizes of reproducing females at the highest temperature. The cholesterol content of the individuals increased with increasing dietary cholesterol; this increase was enhanced at higher temperatures, indicating a higher demand for cholesterol for tissues and probably specifically for membranes. Surprisingly, the daphnids showed different allocation strategies with regard to temperature and dietary sterol availability. The cholesterol content of eggs was enhanced at higher temperature, which suggested that females allocate more cholesterol to their offspring, presumably to ensure sufficient egg development. When dietary cholesterol was limiting, however, females did not allocate more cholesterol to their eggs. Our data suggest that during cyanobacterial blooms, a potential dietary sterol limitation of Daphnia can be intensified at higher water temperatures, which can occur with global warming.
Heterothermy in small, migrating passerine birds during stopover: use of hypothermia at rest accelerates fuel accumulation
Authors: Wojciechowski Michał S. , Pinshow Berry 
Published: September 2009

SUMMARYFor small endothermic animals, heterothermy serves as an energy-saving mechanism for survival in challenging environments, but it may also accelerate fat accumulation in individuals preparing for fuel-demanding activities. This is the first study to demonstrate adaptive hypothermic responses in migrating passerines. While monitoring body temperature (Tb) of eight blackcaps (Sylvia atricapilla) by radiotelemetry, we found that during daytime Tb=42.5±0.4°C (mean ±s.d.); at night Tb decreased to a minimum between 33 and 40°C. We determined the lower limit for normothermy at 37.4°C and found that on 12 out of 34 bird-nights of observations under semi-natural conditions blackcaps reduced their Tb below normothermic resting levels with minimum values of 33 and 34.5°C compared with rest-phase normothermic Tb of 38.8±0.8°C. In birds of body mass (mb) &lt;16.3 g, minimum Tb at night correlated with the individual's mb (r=0.67, P&lt;0.01, N=17),but this was not the case in birds with mb&gt;16.3 g. Minimum nocturnal Tb did not correlate with night-time air temperature (Ta). Measurements of metabolic rate in birds subjected to a Ta of 15°C showed that hypothermia of this magnitude can lead to a reduction of some 30% in energy expenditure compared with birds remaining normothermic. Our data suggest that by reducing the Tb–Ta gradient, blackcaps accelerate their rate of fuel accumulation at a stopover. When body energy reserves are low blackcaps may achieve this reduction by entering hypothermia. Since hypothermia, as seen in blackcaps, may lead to significant energy savings and facilitate body mass gain, we predict that it is common among small migrating passerines.
The influence of ambient temperature and thermal acclimation on hearing in a eurythermal and a stenothermal otophysan fish
Authors: Wysocki Lidia Eva , Montey Karen , Popper Arthur N. 
Published: September 2009

SUMMARYBeing ectothermic, fish body temperature generally depends on ambient water temperature. Thus, ambient temperature might affect various sensory systems,including hearing, as a result of metabolic and physiological processes. However, the maintenance of sensory functions in a changing environment may be crucial for an animal's survival. Many fish species rely on hearing for acoustic orientation and communication. In order to investigate the influence of temperature on the auditory system, channel catfish Ictalurus punctatus was chosen as a model for a eurytherm species and the tropical catfish Pimelodus pictus as a model for a stenotherm fish. Hearing sensitivity was measured with animals acclimated or unacclimated to different water temperatures. Ambient water temperature significantly influenced hearing thresholds and the shape of auditory evoked potentials, especially at higher frequencies in I. punctatus. Hearing sensitivity of I. punctatus was lowest at 10°C and increased by up to 36 dB between 10°C and 26°C. Significant differences were also revealed between acclimated and unacclimated animals after an increase in water temperature but not a decrease. By contrast, differences in hearing thresholds were smaller in P. pictus, even if a similar temperature difference (8°C) was considered. However, P. pictus showed a similar trend as I. punctatus in exhibiting higher hearing sensitivity at the highest tested temperature, especially at the highest frequency tested. The results therefore suggest that the functional temperature dependence of sensory systems may differ depending upon whether a species is physiologically adapted to tolerate a wide or narrow temperature range.
Wetting properties on nanostructured surfaces of cicada wings
Authors: Sun Mingxia , Watson Gregory S. , Zheng Yongmei , Watson Jolanta A. , Liang Aiping 
Published: September 2009

SUMMARY
This study has investigated the wettability of forewings of 15 species of cicadas, with distinctly different wetting properties related to their nanostructures. The wing surfaces exhibited hydrophilic or weak to strong hydrophobic properties with contact angles ranging from 76.8 deg. to 146.0 deg. The nanostructures (protrusions), observed using environmental scanning electron microscopy (ESEM), were classified into four types according to the patterning, diameter (82–148 nm), spacing (44–117 nm) and height(159–446 nm). Surface analysis by X-ray photoelectron spectroscopy (XPS)showed significant differences in wing membrane chemistry. Thus, wetting properties at the macroscopic scale were dependent on slight differences in nanoscale architecture and composition of the wax layer. This investigation offers insights into the diversity of nanostructuring and how subtle small-scale changes may facilitate large changes in wettability.
Hierarchical organisation of the trap in the protocarnivorous plantRoridula gorgonias(Roridulaceae)
Authors: Voigt Dagmar , Gorb Elena , Gorb Stanislav 
Published: September 2009

SUMMARYThe flypaper trap of the protocarnivorous plant Roridula gorgoniasis known to capture various insects, even those having a considerable body size, by using an adhesive, visco-elastic resinous secretion released by glandular trichomes of different dimensions. However, recent experimental studies have shown that the adhesion of long tentacle-shaped trichome secretion is not as strong as previously assumed. One may then ask why this flypaper trap is so highly effective. In the present study, we compared geometry, flexibility and the adhesive properties of secretion in different sized trichomes. We have analysed the gross morphology of the plant and its surfaces using light and cryo-scanning electron microscopy. Trichomes'stiffness and the adhesive properties of their secretion on different surfaces were measured. A combination of structural and experimental results, presented in this study, let us suggest that R. gorgonias represents a three-dimensional trap consisting of three functional hierarchical levels(plant, leaves and trichomes). According to their size, we classified three types of trichomes having a particular arrangement on the leaf. The longest trichomes are more flexible and less adhesive compared with the shortest ones. The latter are 48 times stiffer and their secretion has a 9 times higher adhesive strength. Our data support the hypothesis that the shortest trichomes are adapted to strong, long-term adherence to prey insects, and that the longest trichomes are responsible for initial trapping and entanglement function.
Presence and Characterization of Cell-Free Seminal RNA in Healthy Individuals: Implications for Noninvasive Disease Diagnosis and Gene Expression Studies of the Male Reproductive System
Authors: Huang Shiyun , Li Honggang , Ding Xiaofang , Xiong Chengliang 
Published: September 2009

AbstractBackground: We recently detected cell-free seminal RNA (cfsRNA) and set out to study its concentration, integrity, stability in healthy individuals, and mechanisms for its protection from ribonucleases.Methods: We quantified cfsRNA by reverse-transcription quantitative real-time PCR (RT-qPCR) targeting of the 5′ region of the ACTB (actin, beta) transcript. cfsRNA integrity was analyzed by microcapillary electrophoresis and by amplification of full-length ACTB and DDX4 [DEAD (Asp-Glu-Ala-Asp) box polypeptide 4] transcripts, including measurement of the relative amounts of different regions of ACTB and DDX4 transcripts. Stability of cfsRNA was measured by time-course analysis of different regions of ACTB and DDX4 transcripts. To investigate whether cfsRNA was protected in complexed forms, we processed seminal plasma in 2 ways: filtration through pores of different sizes and Triton X-100 treatment before RNA recovery.Results: cfsRNA concentrations varied from 0.87–3.64 mg/L [mean (SD), 1.75 mg/L (0.92 mg/L)]. Most cfsRNA was present in partially degraded forms, with smaller amounts of middle and 3′ amplicons compared with 5′ amplicons. Although the 3′ region of the DDX4 transcript was degraded completely by 90 min, the 5′ regions of ACTB and DDX4 transcripts were stable up to 24 h. Filtration through 0.22-μm pores reduced ACTB and DDX4 mRNA concentrations by 72% and 61%, respectively. Nearly all seminal ACTB and DDX4 mRNA disappeared after Triton X-100 treatment.Conclusions: Although cfsRNA was partially degraded, it represented diverse transcript species and was abundant, fairly stable, and associated with particles in healthy individuals. cfsRNA may represent a potential noninvasive biomarker of the male reproductive system and of germline epigenetics.
Scrolls over four dimensional varieties
Authors: Tironi Andrea Luigi 
Published: September 2009

Abstract
We point out the relations between the classical and the adjunction-theoretic definition of scroll over varieties of dimension four. In particular, we prove that an adjunction-theoretic scroll of dimension greater than or equal to seven, polarized by a very ample line bundle, is also a classical scroll and that a classical scroll is an adjunction-theoretic scroll with a few exceptions.