bluuebunny/crossref_metadata_2025_split huggingface dataset:
In-vitro effect of flavonoids from Solidago canadensis extract on glutathione S-transferase
Authors: Apáti Pál , Kéry Ágnes , Houghton Peter J , Steventon Glyn B , Kite Geoffrey 
Published: January 2006

Abstract
Solidago canadensis is typical of a flavonoid-rich herb and the effect of an aqueous ethanol extract on glutathione-S-transferase (GST) activity using HepG2 cells was compared with those of the flavonol quercetin and its glycosides quercitrin and rutin, found as major constituents. The composition of the extract was determined by HPLC and rutin was found to be the major flavonoidal component of the extract. Total GST activity was assessed using 1-chloro-2,4-dinitrobenzene as a substrate. The glycosides rutin and quercitrin gave dose-dependent increases in GST activity, with a 50% and 24.5% increase at 250 mm, respectively, while the aglycone quercetin inhibited the enzyme by 30% at 250 mm. The total extract of the herb gave an overall dose-dependent increase, the fractions corresponding to the flavonoids showed activating effects while those containing caffeic acid derivatives were inhibitory. The activity observed corresponds to that reported for similar compounds in-vivo using rats, thus the HepG2 cell line could serve as a more satisfactory method of assessing the effects of extracts and compounds on GST.
Textbook cricket goes to the field: the ecological scene of the neuroethological play
Authors: Dangles Olivier , Casas Jérôme , Coolen Isabelle 
Published: January 2006

SUMMARYSensory ecology has recently emerged as a new focus in the study of how organisms acquire and respond to information from and about their environment. Many sensory scientists now routinely explore the physiological basis of sensing, such as vision, chemoreception or echolocation, in an ecological context. By contrast, research on one of the most performing sensors in the animal kingdom, the wind-sensitive escape system of crickets and cockroaches,has failed so far to encompass ecological and evolutionary considerations. We report survival and behavioural experiments in which wood crickets interacted freely with natural predators in the field. Our results illustrate how the lack of knowledge about the ecology of these insects may entail our understanding of the biological relevance of their wind sensors. We found that predation pressure was most important on early stage crickets. Because laboratory studies have focused exclusively on adults' sensory systems, it is crucial that physical, physiological and neurobiological studies now turn to juveniles.Another common assumption challenged by our results is the nature of the air flow to which crickets are sensitive. Our results identify wolf spiders as the major predatory risk for wood crickets. Air movement stimuli produced by hunting spiders are likely to be strikingly different from air flows produced by flying insects. Yet, our theoretical understanding of air motion sensing is currently drawn from oscillatory flows of flying predators only.
Freezing resistance of antifreeze-deficient larval Antarctic fish
Authors: Cziko Paul A. , Evans Clive W. , Cheng Chi-Hing C. , DeVries Arthur L. 
Published: January 2006

SUMMARYAntarctic notothenioids, along with many other polar marine fishes, have evolved biological antifreeze proteins (AFPs) to survive in their icy environments. The larvae of Antarctic notothenioid fish hatch into the same frigid environment inhabited by the adults, suggesting that they must also be protected by sufficient AFPs, but this has never been verified. We have determined the contribution of AFPs to the freezing resistance of the larvae of three species: Gymnodraco acuticeps, Pagothenia borchgrevinki and Pleuragramma antarcticum. Of the three, only P. borchgrevinki larvae are protected by high, adult levels of AFPs. Hatchling G. acuticeps and P. antarcticum have drastically inadequate AFP concentrations to avoid freezing at the ambient seawater temperature (-1.91°C). We raised G. acuticeps larvae and measured the AFP levels in their blood for ∼5 months post hatching. Larval serum freezing point was -1.34±0.04°C at the time of hatch; it began to decrease only after 30 days post hatch (d.p.h.), and finally reached the adult value (-2.61±0.03°C) by 147 d.p.h. Additionally, AFP concentrations in their intestinal fluids were very low at hatching, and did not increase with age throughout a sampling period of 84 d.p.h.Surviving in a freezing environment without adequate AFP protection suggests that other mechanisms of larval freezing resistance exist. Accordingly, we found that G. acuticeps hatchlings survived to-3.6±0.1°C while in contact with external ice, but only survived to-1.5±0.0°C when ice was artificially introduced into their tissues. P. antarcticum larvae were similarly resistant to organismal freezing. The gills of all three species were found to be underdeveloped at the time of hatch, minimizing the risk of ice introduction through these delicate structures. Thus, an intact integument, underdeveloped gill structures and other physical barriers to ice propagation may contribute significantly to the freezing resistance and survival of these larval fishes in the icy conditions of the Southern Ocean.
Effect of diet quality on carbon and nitrogen turnover and isotopic discrimination in blood of a New World nectarivorous bat
Authors: Mirón M. L. Leticia , Herrera M. L. Gerardo , Ramírez P. Nicte , Hobson Keith A. 
Published: January 2006

SUMMARYDiet composition of carbon and nitrogen (C:N) could affect diet-tissue isotopic discrimination and elemental turnover rate in consumers but studies that test the nature of these changes are scarce. We compared carbon and nitrogen isotopic discrimination and turnover rates in individuals of Pallas'long-tongued bats Glossophaga soricina fed diets with protein soya isolate or amaranth grains as their main source of protein. Diets were of similar protein biological value but the soya diet had higher nitrogen content(2.2%N) and lower C:N ratio (39.6) than the amaranth diet (1.3%N, C:N=40.5). Most bats on the soya diet gained body mass whereas most bats on the amaranth diet lost body mass. Half-lives of carbon (24.3±3.8 days) and nitrogen(25.6±4.4 days) in bats switched to the soya diet were very similar. In contrast, in the bats switched to the amaranth diet, carbon half-life(39.7±3.4 days) was longer than that of nitrogen (25.0±6.0 days). The enrichment in 15N between diet and blood was higher when bats were fed the amaranth diet (4.4±0.2‰) than when they were fed the soya diet (3.3±0.2‰). Similarly, bats on the amaranth diet had higher 13C enrichment (2.0±0.2‰) than bats on the soya diet (0.1±0.1‰). Our results support recent hypotheses of the effect of nutrition on diet-tissue isotopic discrimination and turnover rate, and further shows that blood stable isotope analysis is an adequate approach to track seasonal dietary shifts in wild bats.
Early rearing environment impacts cerebellar growth in juvenile salmon
Authors: Kihslinger Rebecca L. , Nevitt Gabrielle A. 
Published: January 2006

SUMMARY
The size and structure of an animal's brain is typically assumed to result from either natural or artificial selection pressures over generations. However, because a fish's brain grows continuously throughout life, it may be particularly responsive to the environmental conditions the fish experiences during development. Salmon are an ideal model system for studying these effects because natural habitats differ significantly from the hatchery environments in which these fish are frequently reared. For example, in the wild, salmon alevins (i.e. yolk-sac fry) are buried in the gravel, while hatchery environments lack this structural component. We show that the simple manipulation of adding stones to a standard rearing tank can dramatically alter the growth of specific brain structures in steelhead salmon alevins(Oncorhynchus mykiss). We found that alevins reared with stones grew brains with significantly larger cerebella than genetically similar fish reared in conventional tanks. This shift to a larger cerebellar size was, in turn, accompanied by changes in locomotory behaviors - behaviors that correlate strongly to the function of this brain region. We next show that hatchery fish reared in a more naturalistic setting in the wild had significantly larger brains than their lab-reared counterparts. However,relative cerebellar volumes were similar between wild-reared alevins and those reared in the complex treatment in the laboratory. Together our results indicate that, within the first three weeks of life, variation in rearing environment can result in brain differences that are commonly attributed to generations of selection. These results highlight the need to consider enrichment strategies when designing captive rearing facilities for both conservation and laboratory use.
A comparative analysis of thermogenic capacity and cold tolerance in small birds
Authors: Swanson David L. , Liknes Eric T. 
Published: January 2006

SUMMARYSmall birds showing marked seasonal changes in cold tolerance also exhibit winter increases in summit metabolic rate (Msum=maximum cold-induced thermogenesis or thermogenic capacity) relative to summer birds. However, some birds show modest seasonal changes in cold tolerance without winter increases in Msum and others exhibit large seasonal changes in cold tolerance with only minor changes in Msum. Thus, the degree of correlation between cold tolerance and Msum is uncertain and no interspecific study has directly addressed this question. In this study, we measured cold tolerance and Msum in summer- (21 species) and winter- (11 species)acclimatized birds from southeastern South Dakota. Msumwas measured as the maximum oxygen consumption attained during exposure of individual birds to a declining series of temperatures in 79% helium/21%oxygen (helox). Cold tolerance was measured as the temperature at cold limit(TCL), which is the helox temperature that induced hypothermia in individual birds. Residuals from allometric regressions of logMsum and logTCL were significantly and negatively related for summer (R2=0.34, P=0.006) and winter (R2=0.40, P=0.037)birds. Data were also subjected to a comparative analyses with phylogenetically independent contrasts to remove potential confounding effects of phylogeny, and results were similar to the non-phylogenetic analyses, with significant negative correlations in both summer (R2=0.47, P&lt;0.001) and winter (R2=0.40, P=0.049). Thus, birds with high Msum tended to show reduced TCL (i.e. high cold tolerance), suggesting that cold tolerance and summit metabolism are phenotypically linked in small birds.
The effect of endurance exercise on the morphology of muscle attachment sites
Authors: Zumwalt Ann 
Published: January 2006

SUMMARYThe morphology of muscle attachment sites, or entheses, has long been assumed to directly reflect in vivo muscle activity. The purpose of this study is to examine whether variations in muscle activity that are within normal physiological limits are reflected in variations in external attachment site morphology. This study tests the hypothesis that increased muscle activity (magnitude, number and frequency of loading cycles) results in the hypertrophy of muscle attachment sites. The attachment sites of six limb muscles and one muscle of mastication (control) in mature female sheep were measured and compared in exercised (weighted treadmill running for 1 h per day for 90 days) and sedentary control animals. Attachment site surface morphology was assessed by quantifying the size (3D surface area) and complexity (fractal dimension parallel and perpendicular to soft tissue attachment) of the surfaces.The results of this study demonstrate no effect of the exercise treatment used in this experiment on any measure of enthesis morphology. Potential explanations for the lack of exercise response include the mature age of the animals, inappropriate stimulus type for inducing morphological change, or failure to surpass a hypothetical threshold of load for inducing morphological change. However, further tests also demonstrate no relationship between muscle size and either attachment site size or complexity in sedentary control animals. The results of this study indicate that the attachment site morphological parameters measured in this study do not reflect muscle size or activity. In spite of decades of assumption otherwise, there appears to be no direct causal relationship between muscle size or activity and attachment site morphology, and reconstructions of behavior based on these features should be viewed with caution.
Semi-Empirically Based Assessment for Predicting Dilute Gas Transport Properties of F2 and Ar–F2 Fluids
Authors: Papari Mohammad Mehdi , Mohammad-Aghaie Delara , Moghadasi Jalil , Boushehri Ali 
Published: January 2006

Abstract
The purpose of this paper is to extract information about intermolecular pair interaction potential energy and then predict the dilute gas transport properties of Ar–F2 and F2 systems. The potential energies of the two aforementioned systems have been compared with the LJ (12-6) and m-6-8 model potentials. A rather accurate correlation for the viscosity coefficients of each system, which encompasses a temperature range 200 K &lt; T &lt; 3273.15 K, was reproduced from the calculated intermolecular potential energies. The predicted viscosities of Ar–F2 and F2 systems deviate from the literature data to within 1 and 2%, respectively. Furthermore, the calculated potential energies were used to present smooth correlations for other transport properties.
Can we Rely on a General Practitioner's Referral Letter to a Skin Lesion Clinic to Prioritise Appointments and Does it Make a Difference to the Patient's Prognosis?
Authors: Webb Jill B , Khanna A 
Published: January 2006

INTRODUCTION This study was designed to: (i) determine if the priority of referral letters by general practitioners to a plastic surgery skin lesion clinic adhered to the national guidelines, what happened to these patients, and what was the histological diagnosis; and (ii) analyse whether the prognosis at diagnosis of malignant melanoma had improved since the introduction of the 2-week wait for patients with suspected cancer. MATERIALS AND METHODS The study involved a prospective audit questionnaire, retrospective note review and histology report review in the Plastic Surgery Department in a district general hospital and their ‘bespoke’ out-patient clinics. RESULTS Of 202 referral letters, 58 (29%) were referred as 2-week cancer referrals of which 13 (22%) suggested diagnoses that did not fall within the guidelines, and 11 gave no diagnosis. In addition, 84 (42%) had no indication of priority, though the text may suggest the need for it, either explicitly or implied. The prognostic indices for malignant melanoma have not altered since the 2-week wait rule has been implemented. CONCLUSIONS The guidelines are not being adhered to, thus patients with benign lesions are being given undue priority. The history and examination of skin lesions given in the referral letters is insufficient to allow the consultant to prioritise. Since the 2-week rule has be implemented, malignant melanomas have not been diagnosed at an earlier stage.
A Prospective, Randomised, Controlled Trial Comparing Wound Dressings Used in Hip and Knee Surgery: Aquacel and Tegaderm Versus Cutiplast
Authors: Ravenscroft MJ , Harker J , Buch KA 
Published: January 2006

INTRODUCTION Cutiplast (absorbent perforated dressing with adhesive border; Smith & Nephew) is commonly used following orthopaedic operation, but complications of its use have been reported. A prospective, randomised, controlled study was performed to compare the efficacy of Cutiplast versus an Aquacel (hydrofibre dressing; ConvaTec) covered with Tegaderm (vapour-permeable dressing; 3M). PATIENTS AND METHODS Two-hundred patients were randomised to receive one of the two dressings following elective and non-elective surgery of the hip and the knee. We were able to study 183 patients. The condition of the wound and any complications such as skin blistering or signs of infection was noted as was the frequency of dressing changes. RESULTS The Aquacel and Tegaderm dressing was 5.8 times more likely to result in a wound with no complications as compared to a Cutiplast dressing (odds ratio, 5.8; 95% CI 2.8–12.5; P < 0.00001). CONCLUSION Aquacel covered by Tegaderm is a superior dressing to Cutiplast following surgery to the hip and knee.
Hand Washing Rituals in Trauma Theatre: Clean or Dirty?
Authors: Hajipour L , Longstaff L , Cleeve V , Brewster N , Bint D , Henman P 
Published: January 2006

INTRODUCTION The aim of this study was to investigate the degree of contamination of a surgeon's hand following use of chlorhexidine gluconate or alcohol gel as disinfectants. MATERIALS AND METHODS In this prospective, randomised trial, orthopaedic surgeons were allocated to one of two different hand-washing protocols using a randomisation table. The hand-washing protocol dictated that all surgeons should wash for 5 min with chlorhexidine for their first case. Thereafter, the surgeon was randomised to wash for 3 min with either alcohol gel or chlorhexidine. At the end of each procedure, the gloves of each surgeon were carefully removed and the fingertips from each hand were placed on an agar plate. The number of bacterial colonies present after 24 h and 48 h of incubation were recorded for each agar plate by a microbiologist blinded to the washing protocol used. RESULTS Overall, 41 procedures and 82 episodes of hand washings were included in the study. Two episodes were discarded due to contamination at the time of glove removal. Four hands (8%) were contaminated in the chlorhexidine group compared to 19 (34%) in the alcohol group. Fisher's exact test confirmed a significantly higher risk of contamination using alcohol gel compared to chlorhexidine (P = 0.002). In addition, the average bacterial colony count was substantially higher in the alcohol group (20 colony forming units) compared to the chlorhexidine group (5 colony forming units). There was no relationship between the duration of surgery and the degree of contamination (P = 1.12). CONCLUSIONS Alcohol gel disinfectant is not a suitable alternative to chlorhexidine when hand washing before surgery. This study has identified a higher risk of bacterial contamination of surgeons' hands washed with alcohol. This may lead to higher levels of postoperative infection in the event of glove perforation.
A study on the metal binding of humic acid by multitracer technique
Authors: Chang Zheng , Ambe Shizuko , Takahashi Kazuya , Ambe Fumitoshi 
Published: January 2006

SummaryA method combining radioactive ‘multitracer’ and dialysis techniques was developed to study the binding of multiple metal ions to humic acid (HA). Technical problems such as the leakage of small-molecule HA segment and the slow diffusion of metal ions through the dialysis membranes were examined. Under the condition of pH = 4.0,I= 0.100 M NaNO3, [MgII] = 0 M, or [MgII] = 0.500×10-3M, the interactions between Inogashira humic acid and metal ions (BeII, ScIII, ZnII, CoII, MnIIand SrII) were investigated by varying the metal concentrations in a wide range. It was found that as the concentrations of the trace metals are significantly smaller than that of HA, there are abundant binding sites available and there are no competition interactions between the trace metal ions of interest. Therefore, the stability constants for multiple metal ions binding onto humic substances can be obtained readily using the present method. The method is useful for quickly determining trace metal binding onto humic substances in environmental chemistry.
The structure of O-phospho-DL-threonine in potassium, sodium and ammonium environments
Authors: Bryndal Iwona , Lis Tadeusz 
Published: January 2006

Summary
Interactions of O-phospho-DL-threonine (DL-PThr) in the different ionization states with potassium, sodium and ammonium cations have been studied on five crystals (denoted as I-V). In semipotassium salt of DL-PThr (I), the phosphate group adopts the nearly trans conformation, whereas in mono- and disodium salts (II and III) and in mono- and diammonium salts of DL-PThr (IV and V) the phosphate group is situated anticlinal to the rest of the molecule, showing its conformational flexibility depending on the crystal environment, where significant differences are observed in interactions of K+, Na+ and NH4
+ cations with PThr. The crystal packing in each of I-V is dominated by interactions between PThr moieties and the cations and hydrogen bond networks involving the phosphate, carboxyl, and amino groups of PThr moieties and water molecules. In crystal I, water molecules are not involved in potassium cation complexation. In crystals II and III, sodium cations show a preference for water molecules over PThr anions as ligands in coordination spheres. Especially in crystals I-III, water molecules are involved in very extensive networks of hydrogen-bond interactions.
Na+/H+ Exchanger Regulatory Factor-1 Is a Hematopoietic Ligand for a Subset of the CD34 Family of Stem Cell Surface Proteins
Authors: Tan Poh C. , Furness Sebastian G.B. , Merkens Helen , Lin Shujun , McCoy Marcia L. , Roskelley Calvin D. , Kast Jürgen , McNagny Kelly M. 
Published: January 2006

Abstract
CD34 and its relatives, podocalyxin and endoglycan, comprise a family of surface sialomucins expressed by hematopoietic stem/progenitor cells and vascular endothelia. Recent data suggest that they serve as either pro- or antiadhesion molecules depending on their cellular context and their post-translational modifications. In addition, their ability to function as blockers of adhesion may be further regulated by their subcellular localization in membrane microdomains via activation-dependent linkage with the actin cytoskeleton. To gain further insights into the function and regulation of CD34-type molecules, we sought to identify the intracellular ligands that govern their localization. Using both genetic and biochemical approaches, we have identified the Na+/H+ exchanger regulatory factor-1 (NHERF-1) as a selective ligand for podocalyxin and endoglycan but not for the closely related CD34. Furthermore, we show that NHERF-1 is expressed by all c-kit+ /lineage marker− /Sca-1+ cells, which are known to express podocalyxin and have long-term repopulating abilities. Finally, we show that these proteins relocalize and colocalize in response to cytokine signaling. The results suggest that this cytosolic adaptor protein may be important for mobilization of CD34-type proteins in the plasma membrane and may thereby regulate their ability to block or enhance hematopoietic cell adhesion.
Self‐Organized Nanostructures in Hard Ceramic Coatings
Authors: Mayrhofer P. H. , Mitterer C. , Clemens H. 
Published: January 2006

AbstractNanostructures have attracted increasing interest in modern development of hard coatings for wear‐resistant applications. In plasma‐assisted vapor deposited thin films, nanostructures can evolve during growth or a post‐deposition annealing treatment. In this review we demonstrate, using TiB2.4, TiN–TiB2, Ti0.34Al0.66N, and Ti(N,B) as model‐coatings, the development of nanostructures and its influence on the mechanical properties of ceramic thin films. For TiB2.4 and TiN–TiB2 a two‐dimensional and three‐dimensional nanostructure, respectively, organizes itself during growth by segregation driven processes. Growth of Ti0.34Al0.66N and Ti(N,B) results in the formation of a supersaturated TiN based phase, which tends to decompose into its stable constituents during post‐deposition annealing via the formation of nm‐sized domains. As the hardness of a material is determined by resistance to bond distortion and dislocation formation and motion, which depend on the amount and constitution of obstacles provided, there is a direct relation between hardness and nanostructure.