bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapid cold-hardening increases the freezing tolerance of the Antarctic midgeBelgica antarctica
Authors: Lee Richard E. , Elnitsky Michael A. , Rinehart Joseph P. , Hayward Scott A. L. , Sandro Luke H. , Denlinger David L. 
Published: January 2006

SUMMARYRapid cold-hardening (RCH) is well known to increase the tolerance of chilling or cold shock in a diverse array of invertebrate systems at both organismal and cellular levels. Here, we report a novel role for RCH by showing that RCH also increases freezing tolerance in an Antarctic midge, Belgica antarctica (Diptera, Chironomidae). The RCH response of B. antarctica was investigated under two distinct physiological states: summer acclimatized and cold acclimated. Summer-acclimatized larvae were less cold tolerant, as indicated by low survival following exposure to-10°C for 24 h; by contrast, nearly all cold-acclimated larvae survived-10°C, and a significant number could survive -15°C. Cold-acclimated larvae had higher supercooling points than summer larvae. To evaluate the RCH response in summer-acclimatized midges, larvae and adults, maintained at 4°C, were transferred to -5°C for 1 h prior to exposures to -10, -15 or -20°C. RCH significantly increased survival of summer-acclimatized larvae frozen at -10°C for 1 h compared with larvae receiving no cold-hardening treatment, but adults, which live for only a week or so in the austral summer, lacked the capacity for RCH. In cold-acclimated larvae, RCH significantly increased freeze tolerance to both -15 and -20°C. Similarly,RCH significantly increased cellular survival of fat body, Malpighian tubules and gut tissue from cold-acclimated larvae frozen at -20°C for 24 h. These results indicate that RCH not only protects against non-freezing injury but also increases freeze tolerance.
The neuropeptide proctolin potentiates contractions and reduces cGMP concentrationviaa PKC-dependent pathway
Authors: Philipp Berit , Rogalla Nicole , Kreissl Sabine 
Published: January 2006

SUMMARYAs in many other arthropods, the neuropeptide proctolin enhances contractures of muscles in the crustacean isopod Idotea emarginata. The enhancement of high K+-induced contractures by proctolin (1μmol l-1) was mimicked upon application of the protein kinase C(PKC) activator phorbol-12-myristate 1-acetate (PMA) and was inhibited by the PKC inhibitor bisindolylmaleimide (BIM-1). The potentiation was not inhibited by H89, a protein kinase A (PKA) inhibitor. Proctolin did not change the intracellular concentration of 3′,5′-cyclic adenosine monophosphate (cAMP) whereas it significantly reduced the intracellular concentration of 3′,5′-cyclic guanosine monophosphate (cGMP). The reduction of cGMP was not observed in the presence of the PKC inhibitor BIM-1. 8-Bromo-cGMP, a membrane-permeable cGMP analogue, reduced the potentiating effect of proctolin on muscle contracture. We thus conclude that proctolin in the studied crustacean muscle fibres induces an activation of PKC, which leads to a reduction of the cGMP concentration and, consequently, to the potentiation of muscle contracture.
The role of branchial carbonic anhydrase in acid-base regulation in rainbow trout (Oncorhynchus mykiss)
Authors: Georgalis T. , Perry S. F. , Gilmour K. M. 
Published: January 2006

SUMMARYThe objective of the present study was to examine the branchial distribution of the recently identified rainbow trout cytoplasmic carbonic anhydrase isoform (tCAc) and to investigate its role in the regulation of acid-base disturbances in rainbow trout (Oncorhynchus mykiss). In situ hybridization using an oligonucleotide probe specific to tCAc revealed tCAc mRNA expression in both pavement cells and mitochondria-rich cells (chloride cells). Similarly, using a homologous polyclonal antibody,tCAc immunoreactivity was localized to pavement cells and mitochondria-rich cells in the interlamellar region and along the lamellae of the gills. Exposure of rainbow trout to hypercarbia (∼0.8% CO2) for 24 h resulted in significant increases in tCAc mRNA expression (∼20-fold;quantified by real-time PCR) and protein levels (∼1.3-fold; quantified by western analysis) but not enzyme activity (assessed on crude gill homogenates using the delta-pH CA assay). Inhibition of branchial CA activity in vivo using acetazolamide reduced branchial net acid excretion significantly by 20%. This effect was enhanced to a 36% reduction in branchial net acid excretion by subjecting the trout to hypercarbia (∼0.8%CO2) for 10 h prior to acetazolamide injection, an exposure that significantly increased branchial net acid excretion. The results of the present study support the widely held premise that branchial intracellular CA activity (tCAc) plays a key role in regulating acid-base balance in freshwater teleost fish.
Corners and bubble wrap: the structure and texture of surfaces influence crayfish exploratory behaviour
Authors: Patullo B. W. , Macmillan D. L. 
Published: January 2006

SUMMARYTouch is a principal sense in all animals. It is potentially important in species of freshwater crayfish that encounter murky waters or are nocturnal. Little is known about how tactile (touch) stimuli affect exploratory behaviour under these conditions. We placed animals in different tactile situations at the start of an exploration in a dark arena and tracked the position of the body and antennae to test whether subsequent search behaviour was affected. Individuals were exposed to differently textured walls, channelled out along a wall, or released in contact with no, one, or two walls. A corner arrangement of surfaces, where individuals started near two walls at right angles,produced behaviour that differed from that of other configurations; animals chose one wall and then maintained a close distance from the wall along which they were moving. The distance from a wall adopted by a crayfish walking parallel to it was affected by the texture of the wall. These results on the influence of tactile stimuli on crayfish exploratory behaviour may have implications for other taxa.
Dynamically similar locomotion in horses
Authors: Bullimore Sharon R. , Burn Jeremy F. 
Published: January 2006

SUMMARYIt is possible for animals of very different sizes to use the same patterns of locomotion, i.e. to move in a `dynamically similar fashion'. This will only occur, however, if relevant biomechanical parameters scale with size in such a way that they compensate for the effects of size differences. Here we apply this principle to understanding the effects of size on locomotion within a species: the domestic horse. We predict that, without any factor to compensate for size differences, detectable deviations from dynamically similar locomotion would occur over the size range present in adult horses. We measured relative stride length (RSL) and duty factor (DF) in 21 trotting horses (body mass: 86-714 kg), and interpolated the data to predict RSL and DF at equivalent speeds (Froude numbers: 0.5, 0.75, 1.0). RSL and DF at equal Froude number were not significantly related to body mass. This is consistent with the hypothesis that horses trot in a dynamically similar fashion at equal Froude number. We show that the nonlinear stress-strain relationship of tendon can contribute to reducing deviations from dynamic similarity, `buffering' the effects of variation in body mass, but conclude that this effect is unlikely to explain fully our results. This suggests that a `compensatory distortion'may occur in horses, counteracting the effects of size differences. The approach used here is also applicable to understanding the consequences of size changes within an individual during growth.
Functions of the subesophageal ganglion in the medicinal leech revealed by ablation of neuromeres in embryos
Authors: Cornford Andrea , Kristan William B. , Malnove Sierra , Kristan William B. , French Kathleen A. 
Published: January 2006

SUMMARYTwo general trends in the evolution of the nervous system have been toward centralization of neuronal somata and cephalization of the central nervous system (CNS). These organizational trends are apparent in the nervous system of annelid worms, including leeches. To determine if the anterior brain of the leech serves functions similar to those of the brains of more complex organisms, including vertebrates, we ablated one of the two major regions of the cephalic brain - the subesophageal ganglion (SubEG). For anatomical reasons, ablations were performed in embryos, rather than in adults. At the end of embryonic development, we observed the leeches' spontaneous behaviour and their responses to moderate touch. We observed that, although the midbody ganglia of the leech CNS display a high degree of local autonomy, the cephalic brain provides generalized excitation to the rest of the CNS, is a source of selective inhibition that modulates behaviour, integrates sensory information from the head with signals from the rest of the body, and plays an important role in organizing at least some complicated whole-body behaviours. These roles of the leech cephalic brain are common features of brain function in many organisms, and our results are consistent with the hypothesis that they arose early in evolution and have been conserved in complex nervous systems.
Heterogeneous perfusion of the paired gills of the abaloneHaliotis irisMartyn 1784: an unusual mechanism for respiratory control
Authors: Ragg Norman L. C. , Taylor H. Harry 
Published: January 2006

SUMMARYThe abalone Haliotis iris retains the ancestral gastropod arrangement of a pair of bipectinate gills (ctenidia). The gills share a single branchial chamber, are supplied from a common haemolymph sinus and effectively support the whole of oxygen uptake by the animal. Using chronic indwelling cannulae and pulsed Doppler probes, post-branchial haemolymph oxygen partial pressures (PaO2) and haemolymph flow rates were measured in the left and right efferent ctenidial veins. During periods of internal hypoxia following emersion and handling, total branchial haemolymph flow (24.4±3.6 ml kg-1min-1) was partitioned nearly equally between the left and right gills (13.3±2.6 and 10.8±1.4 ml kg-1min-1, respectively) and their PaO2values were similar (81.9±6.1 and 87.3±4.7 mmHg, respectively). In animals settled for &gt;24 h, branchial haemolymph flow decreased to 9.1±2.1 ml kg-1 min-1, primarily resulting from a virtual shutdown of the left gill flow to only 4.6% of total flow (left,0.41±0.34 ml kg-1 min-1; right, 8.6±2.0 ml kg-1 min-1). At rest, right gill PaO2 (85.5±6.8 mmHg) was essentially unchanged while PaO2 of the slowly perfused left gill rose to 105.3±10.2 mmHg, close to the PO2 of the exhalant seawater (104.5±3.1 mmHg). The aerobic metabolic scope of H. iris therefore appears to be met primarily by circulatory adjustments at the left gill, which at rest is highly perfusion limited (left Ldiff, 0.14±0.07;right Ldiff, 0.44±0.08).
The identification and role of a novel eicosanoid in the reproductive behaviour of barnacles (Balanus balanus)
Authors: Maskrey Ben H. , Taylor Graham W. , Rowley Andrew F. 
Published: January 2006

SUMMARY
Post-copulatory behaviour in barnacles involves a violent rocking movement of the opercular valves, which is thought to contribute to the expulsion of oocytes through the oviduct into the mantle cavity where they are fertilised. We demonstrate in this study that the seminal vesicles/testis of the subtidal barnacle Balanus balanus produce a biologically active factor,barnacle muscle stimulatory factor (BMSF), which causes a significant increase in cirral and body muscular activity. BMSF was identified using a combination of high performance liquid chromatography and mass spectrometry as a novel eicosanoid/oxylipin, 8,13-dihydroxyeicosapentaenoic acid. This is rapidly inactivated under mild acid conditions to form a complex range of triene and pentaene chromophore-containing products that have only been partially identified. Injection of purified BMSF into the mantle cavity of barnacles caused the rocking movements of the opercular valves as reported following fertilisation. In excised barnacles, it also caused muscular contractions of the whole body mass. The breakdown products of BMSF, however, were without such activities. The function of BMSF in facilitating fertilisation in barnacles is comparable to the role of other eicosanoids in human reproduction, reinforcing the view that these compounds have conserved activities in both invertebrates and vertebrates.
Significance of Na+ current in the excitability of atrial and ventricular myocardium of the fish heart
Authors: Haverinen Jaakko , Vornanen Matti 
Published: January 2006

SUMMARY
The present study examines the importance of the Na+ current(INa) in the excitability of atrial and ventricular myocardium of the rainbow trout heart. Whole-cell patch-clamp under reduced sarcolemmal Na+ gradient showed that the density of INa is similar in atrial and ventricular myocytes of the trout heart, and the same result was obtained when INa was elicited by chamber-specific action potentials (AP) in normal physiological saline solution. However, the maximum rate (Vmax) of AP upstroke, measured with microelectrodes in intact trout heart, was 21% larger in atrium than ventricle, and thus in variance with the similar INa density of the two myocyte types. Furthermore, Vmax calculated from the INa was 2.1 and 3.2 times larger for atrium and ventricle, respectively, than the values obtained from the APs. The discrepancy between INa of isolated myocytes and Vmax of intact muscle is only partly explained by the inward rectifier K+ current(IK1), which overlaps INa and decreases the net depolarising current. Clear differences exist in the voltage dependence of steady-state activation and inactivation as well as in the inactivation kinetics of INa between atrial and ventricular myocytes. As a result of a more negative voltage dependence of INa activation, smaller IK1 and higher input resistance of atrial myocytes, the voltage threshold for AP generation is more negative in atrium than ventricle of the trout heart. These findings suggest that atrial muscle is more readily excitable than ventricular muscle,and this difference is partly due to the properties of the atrial INa.
Surgical Treatment of Varicose Veins: Effect of Rationing
Authors: Re Harris Mark , Davies R Justin , Brown Suki , Jones Stephen M , Eyers Paul S , Chester John F 
Published: January 2006

INTRODUCTION A substantial part of vascular surgical workload is devoted to the treatment of varicose veins. To control demand for cosmetic venous surgery, primary care trusts in Somerset introduced clinical criteria in 2000 for the referral and treatment of varicose veins based on the presence of skin change or ulceration, a history of bleeding, or two or more episodes of thrombophlebitis. PATIENTS AND METHODS A comparison of workload and case mix for the referral and treatment of new patients presenting with varicose veins to the Taunton and Somerset Hospital was carried out over two 6-month periods, before and after the introduction of clinically based assessment criteria. RESULTS A total of 134 operations for varicose veins were carried out in 2000 and 85 such operations in 2002/03 after the introduction of new referral criteria (P = 0.001). Of these, 69% (92/134) were day-case procedures in 2000 compared to only 48% (41/85) in 2002/03 (P = 0.004). There was no significant difference in the type of cases (e.g. single, bilateral or recurrent surgery) performed as a day-case (P = 0.34) or as an in-patient (P = 0.43) over the two periods. There was, however, a significant difference (P = 0.007) in the mean ages of patients in the two periods (48.5 years in period 1; 57.8 years in period 2) and in the average ASA grade (1.15 in period 1; 1.42 in period 2; P = 0.0002). CONCLUSION The introduction of clinical criteria for the referral and treatment of varicose veins reduced workload by 37%.
Plain Abdominal Radiographs: Can we Interpret Them?
Authors: Lim C Beverly B , Chen Vivian , Barsam Allon , Berger Jeremy , Harrison Richard A 
Published: January 2006

INTRODUCTION Plain abdominal radiographs commonly form a part of medical assessments. Most of these films are interpreted by the clinicians who order them. Interpretation of these films plays an important diagnostic role and, therefore, influences the decision for admission and subsequent management of these patients. The aim of this study was to find out how well doctors in different specialties and grades interpreted plain abdominal radiographs. MATERIALS AND METHODS A total of 76 doctors from the Departments of Accident & Emergency, Medicine, Surgery and Radiology (17, 32, 23 and 4, respectively) participated in the study which involved giving a diagnosis for each of 14 plain abdominal radiographs (5 ‘normal’ and 9 ‘abnormal’). They were also asked the upper limit of normal dimensions of small bowel and large bowel. One point was awarded for correctly identifying whether a radiograph was normal/abnormal, 1 point for the correct diagnosis and 1 point for the correct bowel dimensions, giving a total score of 30. RESULTS Mean scores out of 30 for specialties were as follows: Accident & Emergency 13.1 (range, 2–22), Medicine 11.2 (range, 2–23), Surgery 15.0 (range, 8–24) and Radiology 17.0 (range, 14–20; P = 0.241). Mean scores out of 30 for different grades of doctors were as follows: pre-registration house officers 10.8 (range, 4–20), senior house officers 13.0 (range, 2–22), registrars/staff grades 13.8 (range, 2–23) and consultants 17.3 (range, 12–24; P = 0.028). Fifteen out of 76 (19.7%) doctors correctly identified the upper limit of normal dimension of small bowel; 24 out of 76 (31.6%) correctly identified the upper limit of normal dimension of large bowel. DISCUSSION The level of seniority positively correlated with skills of plain abdominal radiograph interpretation. A large number of doctors were unable to give the correct upper limit of normal dimensions for small and large bowel. CONCLUSIONS All doctors could benefit from further training in the interpretation of plain abdominal radiographs. This could perhaps take place as formal teaching sessions and be included in induction programmes. Until then, plain abdominal films should ideally be reported by radiologists where there are clinical uncertainties; important management decisions made by junior doctors based on these films should at least be confirmed with a registrar, if not a consultant.
Patients with Clinical Acute Appendicitis Should have Pre-operative Full Blood Count and C-Reactive Protein Assays
Authors: Birchley D 
Published: January 2006

INTRODUCTION The role of inflammatory markers in the diagnosis of acute appendicitis has not been clearly defined. The aims of this prospective audit were to define the role of the serum markers of inflammation total white cell count, neutrophil count and C-reactive protein in the diagnosis of acute appendicitis with particular reference to the discrimination between uncomplicated and complicated appendicitis, and the prediction of abscess. PATIENTS AND METHODS The author compiled a prospective database over a 13-month period of all appendicectomies performed. After five exclusions (three having no notes for review and two having confounding second morbidity in the presence of a normal appendix), the data relating to 75 patients were analysed. RESULTS In patients judged on clinical grounds to require laparotomy for suspected acute appendicitis, white cell count and neutrophil count distinguish acute appendicitis from normal appendices when used as categorical variables, though they do not reflect the presence of abscess. C-reactive protein neither distinguishes appendicitis from normal, nor predicts abscess when used as a categorical variable, though higher levels suggest abscess. CONCLUSIONS Laboratory tests of the white cell count, neutrophil count and C-reactive protein are more effective in supporting a clinical diagnosis of acute appendicitis in patients with typical clinical features than in excluding the diagnosis.
From Meeting Presentation to Peer-Review Publication – a UK Review
Authors: Weale AR , Edwards AG , Lear PA , Morgan JDT 
Published: January 2006

INTRODUCTION Annual academic surgical meetings provide a forum for the discussion of research. For the wide-spread dissemination of this information, peer-reviewed publication is required. The aim of this study was to compare the amount of presentations which go on to publication from 4 UK-based surgical meetings. MATERIALS AND METHODS We determined whether a presentation had led to a successful publication using PubMed, a median of 28 months following each meeting. We compared the ASGBI publication rate with the meetings of the Vascular Surgical Society (VSSGBI), the Association of Coloproctology of Great Britain and Ireland (ACPGBI) and the British Transplantation Society (BTS). We also compared the median impact factor of journals used. RESULTS The ASGBI and BTS had a similar rate of presentations resulting in publication, with 35% and 36% at 2 years, respectively. The VSS had a significantly greater proportion of presentations resulting in publication (54% at 2 years; P = 0.004), whilst the ACPGBI had significant fewer (24% at 2 years; P = 0.006). There was no difference in the median impact factors of the journals used between the meetings (Kruskal Wallis P = 0.883). CONCLUSIONS There is a significant variation between meetings in terms of turning presentations into publications. However, the majority of abstracts have still not been fully published within 2 years of presentation at the meeting.
Determination of Clopidogrel Resistance by Whole Blood Platelet Aggregometry and Inhibitors of the P2Y12 Receptor
Authors: Ivandic Boris T , Schlick Philipp , Staritz Peter , Kurz Kerstin , Katus Hugo A , Giannitsis Evangelos 
Published: January 2006

Abstract
Background: Inhibition of platelet aggregation by clopidogrel may be insufficient in up to 30% of users. These nonresponders carry an increased risk of cardiovascular events. We reported here a simple assay to study clopidogrel responsiveness.
Methods: Electrical impedance aggregometry was performed in diluted whole blood in the presence of 5 and 20 μmol/L ADP. Some samples were incubated with 0.1 mmol/L methyl-S-adenosine monophosphate (MeSAMP), a P2Y12 receptor blocker, to maximize inhibition of aggregation before aggregometry. To validate the assay, we analyzed 6-min impedance in 21 healthy probands and 244 patients with coronary artery disease (CAD).
Results: At 5 μmol/L ADP, the imprecision of the assay was 11%. Mean (SD) impedance of the healthy cohort was 12.2 (2.2) Ω. The mean − 3 SD was used to define the cutoff for clopidogrel responsiveness: responders and nonresponders exhibited a 6-min impedance ≤5 Ω and &gt;5 Ω, respectively. Samples from nonresponders were incubated with MeSAMP and analyzed again to distinguish pharmacokinetic and pharmacodynamic types of resistance. Sixteen percent of CAD patients were classified as nonresponders (38 and 2 cases of pharmacokinetic and pharmacodynamic resistance, respectively). Female sex was strongly associated with clopidogrel resistance (P = 0.0002, Fisher exact test). A higher clopidogrel loading dose (P = 0.0353, Mann–Whitney U-test) was given to responders (median, 450 mg) than nonresponders (median, 300 mg). Age and cardiovascular diagnosis showed no significant associations.
Conclusions: Impedance aggregometry using 5 μmol/L ADP is a useful tool for studying clopidogrel responsiveness. MeSAMP allows characterization of responsiveness “on treatment” and may be useful for optimizing clopidogrel dosing.