bluuebunny/crossref_metadata_2025_split huggingface dataset:
Complex interactions among mammalian carnivores in Australia, and their implications for wildlife management
Authors: Glen Alistair S. , Dickman Chris R. 
Published: June 2006

ABSTRACTMammalian carnivore populations are often intensively managed, either because the carnivore in question is endangered, or because it is viewed as a pest and is subjected to control measures, or both. Most management programmes treat carnivore species in isolation. However, there is a large and emerging body of evidence to demonstrate that populations of different carnivores interact with each other in a variety of complex ways. Thus, the removal or introduction of predators to or from a system can often affect other species in ways that are difficult to predict. Wildlife managers must consider such interactions when planning predator control programmes. Integrated predator control will require a greater understanding of the complex relationships between species.In many parts of the world, sympatric species of carnivores have coexisted over an evolutionary time scale so that niche differentiation has occurred, and competition is difficult to observe. Australia has experienced numerous introductions during the past 200 years, including those of the red fox (Vulpes vulpes) and the feral cat (Felis catus). These species now exist in sympatry with native mammalian predators, providing ecologists with the opportunity to study their interactions without the confounding effects of coevolution.Despite an increasing body of observational evidence for complex interactions among native and introduced predators in Australia, few studies have attempted to clarify these relationships experimentally, and the interactions remain largely unacknowledged. A greater understanding of these interactions would provide ecologists and wildlife managers world‐wide with the ability to construct robust predictive models of carnivore communities, and to identify their broader effects on ecosystem functioning. We suggest that future research should focus on controlled and replicated predator removal or addition experiments. The dingo (Canis lupus dingo), as a likely keystone species, should be a particular focus of attention.
The antiarrhythmic effects of ischaemic preconditioning in anaesthetized dogs are prevented by atropine; role of changes in baroreceptor reflex sensitivity
Authors: Babai László , Papp Julius Gy , Parratt James R , Végh Ágnes 
Published: June 2006

Dogs, anaesthetized with chloralose and urethane, were subjected to a 25 min occlusion of the left anterior descending coronary artery. This resulted in ventricular ectopic activity, a reduction in baroreflex sensitivity (BRS, measured following the intravenous administration of phenylephrine), elevations in the epicardial ST‐segment and increases in the degree of inhomogeneity of electrical activation, both measured from the ischaemic region of the left ventricular wall.
These changes were markedly reduced when the 25 min occlusion was preceded, 20 min earlier, by a 5 min (preconditioning) occlusion of the same coronary artery (e.g. VF during ischaemia reduced from 40% in the controls to 0%; P<0.05; BRS increased from 1.22±0.23 pre‐occlusion to 1.61±0.25 mmHg ms−1 post‐occlusion in preconditioned dogs; cf. 1.28±0.29 to 0.45±0.12 mmHg ms−1 respectively in the controls, P<0.05).
These beneficial effects of preconditioning were prevented by the administration, 10 min prior to the 25 min coronary artery occlusion, of atropine (1 mg kg−1 i.v. followed by a continuous infusion of 0.04 mg kg−1 h−1). For example, VF during occlusion was increased from 0% in the preconditioned dogs to 40% (P<0.05) in the presence of atropine and BRS was again reduced during occlusion (from 1.75±0.29 to 0.30±0.08 mmHg ms−1; P<0.05).
We conclude that preconditioning reduces arrhythmia severity during ischaemia by favourably modifying cardiac autonomic receptor mechanism through enhancing vagal influences.

British Journal of Pharmacology (2002) 135, 55–64; doi:10.1038/sj.bjp.0704445
Assessing the emetic potential of PDE4 inhibitors in rats
Authors: Robichaud A , Savoie C , Stamatiou P B , Lachance N , Jolicoeur P , Rasori R , Chan C C 
Published: June 2006

Type 4 phosphodiesterase (PDE4) inhibitors mimic the pharmacological actions of alpha2‐adrenoceptor antagonists. This has been postulated as the mechanism by which PDE4 inhibitors induce emesis and was also demonstrated by their ability to reverse xylazine/ketamine‐induced anaesthesia. We further characterized this latter effect since it appears to reflect the emetic potential of PDE4 inhibitors.
Selective inhibitors of PDE 1, 2, 3, 4 and 5 were studied in rats, on the duration of anaesthesia induced by the combination of xylazine (10 mg kg−1, i.m.) and ketamine (10 mg kg−1, i.m.) PMNPQ (i.e. 6‐(4‐pyridylmethyl)‐8‐(3‐nitrophenyl)quinoline)  –  PDE4 inhibitor: 0.01 – 3 mg kg−1), like MK‐912 (alpha2‐adrenoceptor antagonist: 0.01 – 3 mg kg−1), dose‐dependently reduced the duration of anaesthesia. In contrast, vinpocetine (PDE1 inhibitor), EHNA (PDE2 inhibitor), milrinone (PDE3 inhibitor) and zaprinast (PDE5 inhibitor) had no significant effect at the doses tested (1 – 10 mg kg−1). Analysis of plasma and cerebrospinal fluid (CSF) of treated animals confirmed the absorption and distribution to the brain of the inactive inhibitors.
Neither MK‐912 (3 mg kg−1) nor PMNPQ (0.1 – 1 mg kg−1) altered the duration of anaesthesia induced via a non‐alpha2‐adrenoceptor pathway (sodium pentobarbitone 50 mg kg−1, i.p.)
Central NK1 receptors are involved in PDE4 inhibitor‐induced emesis. Consistently, [sar9, Met(O2)11]‐substance P (NK1 receptor agonist, 6 μg i.c.v.) reduced the duration of anaesthesia induced by xylazine/ketamine.
In summary, this model is functionally coupled to PDE4, specific to alpha2‐adrenoceptors and relevant to PDE4 inhibitor‐induced emesis. It therefore provides a novel way of evaluating the emetic potential of PDE4 inhibitors in rats.

British Journal of Pharmacology (2002) 135, 113–118; doi:10.1038/sj.bjp.0704457
Cyclic GMP‐dependent vasodilatory properties of LASSBio 294 in rat aorta
Authors: Silva C L M , Noël F , Barreiro E J 
Published: June 2006

The effects of LASSBio 294, a new 3,4‐methylenedioxybenzoyl‐2‐thienylhydrazone, on vascular tonus were investigated in isolated rat aortic rings.
LASSBio 294 induced a concentration‐dependent relaxation of intact rat aortic rings with an inhibitory concentration (IC50) of 74 μM (95% confidence limits: 59 – 92). The mechanical removal of the endothelium abolished this effect.
In aortic rings with intact endothelium the effect of 100 μM LASSBio 294 was not altered by the pharmacological inhibition of NOS and cyclo‐oxygenase pathways with 500 μM L‐NAME and 10 μM indomethacin, respectively.
LASSBio 294 (100 μM) was able to relax aortic rings pre‐contracted with high extracellular K+ (KCl 100 mM).
The relaxant effect of LASSBio 294 was fully reversed (and prevented) by the addition of 1 μM ODQ (1H‐(1,2,4)oxadiazolo[4,3‐a]quinoxaline‐1‐one), a selective inhibitor of soluble guanylate cyclase.
LASSBio 294 (100 μM) had no direct effect on PDE3 and PDE4 activities, however, it increased by 150% cyclic GMP content in aortic rings pre‐treated with 100 μM L‐NAME and 10 μM indomethacin, as did 1 μM zaprinast, a selective PDE5 inhibitor.
In conclusion, LASSBio 294 induced relaxation of isolated rat aorta probably by directly increasing cyclic GMP content, possibly as a consequence of PDE5 inhibition.

British Journal of Pharmacology (2002) 135, 293–298; doi:10.1038/sj.bjp.0704473
Effects of treadmill inclination and speed on forelimb muscle activity and kinematics in the horse
Authors: Hodson-Tole Emma 
Published: June 2006

AbstractThe study aimed to investigate the effect of speed and incline on EMG activity in thebrachiocephalicusmuscle and the long and lateral heads of thetriceps brachiimuscle. Six horses were exercised on a treadmill at walk (1.7 m s-1), trot (4.0 m s-1) and right lead canter (7.2 m s-1) on a 0 and 8% incline. Kinematics (120 Hz) and electromyography (EMG) (2000 Hz) data were collected simultaneously from the left forelimb of each horse. Significant differences in relation to velocity and incline were identified using two-way ANOVA andpost hocStudent–Newman–Keuls tests (P≪0.05). The degree of association between timing of peak EMG intensity and the timing of maximum protraction/retraction angles was assessed using ANCOVA. Increases in velocity led to an increase in stride length and reduction in stride duration. Exercise on the incline increased stance duration and decreased swing duration, while limb protraction/retraction increased. The time of peak EMG activity in thebrachiocephalicuswas highly related to time of maximum limb retraction (r2=0.84). The time of peak EMG activity in the long head of thetriceps brachiiwas highly associated with time of maximum limb protraction (r2=0.87). Increases in velocity and incline both caused an increase in the intensity of the EMG signal from each muscle. Duration of EMG activity was prolonged in the long head of thetriceps brachiimuscle and in thebrachiocephalicusmuscle as velocity increased. Treadmill speed and slope therefore both alter the workload placed on forelimb muscles.
Incidence of Pediatric and Neonatal Intensive Care Unit–Acquired Infections
Authors: Banerjee Shailendra N. , Grohskopf Lisa A. , Sinkowitz-Cochran Ronda L. , Jarvis William R. ,   National Nosocomial Infections Surveillance System; the Pediatric Prevention Network
Published: June 2006

Objective.To compare the cumulative incidence of infections acquired in the pediatric intensive care unit (PICU) and neonatal intensive care unit (NICU).Design.Estimation of the cumulative incidence of infections with data obtained from the Pediatric Prevention Network (PPN) point-prevalence survey and observed rates from the National Nosocomial Infections Surveillance (NNIS) system.Setting.Ten hospitals participated in both the PPN survey and NNIS system.Participants.All patients present on the PPN survey dates (August 4, 1999, or February 1, 2000) in the NICUs or PICUs of the PPN hospitals were included in the survey. Point prevalences for PICU-acquired and for NICU-acquired infections at these hospitals were calculated from the survey data. The cumulative incidence rates were estimated from the point prevalence rates using a standard formula and a standard method for calculating the time to recovery (ie, on the basis of the assumption that discontinuance of antimicrobial therapy indicates recovery from infection); alternate methods to judge the time to recovery from infection were also explored.Results.The average cumulative incidence of intensive care unit-acquired infection for NICUs and PICUs combined (all units), as measured by NNIS, was 14.1 cases per 100 patients; in comparison, the prevalence was 14.06 cases for 100 patients (median difference, —0.95 cases per 100 patients; 95% confidence interval, —4.6 to 5.0 cases per 100 patients), and the estimated cumulative incidence using the standard method of calculating the time to recovery was 13.8 cases per 100 patients (median difference, —1.5 cases per 100 patients; 95% confidence interval, —9.1 to 2.9 cases per 100 patients). Estimates of cumulative incidence using alternate methods for calculation of time to recovery did not perform as well (range, 4.9-100.9 cases per 100 patients). The average incidence density for all units, as measured by the NNIS system, was 6.8 cases per 1,000 patient-days, and the estimate of incidence density using the standard method of calculating the time to recovery was 3.6 cases per 1,000 patient-days (median difference, 4.3 cases per 1,000 patient-days; 95% confidence interval, 0.9 to 9.2 cases per 1,000 patient-days). Estimated incidence densities using alternate methods for determining recovery time correlated closely with observed incidence densities.Conclusions.In this patient population, the simple point prevalence provided the best estimate of cumulative incidence, followed by use of a standard formula and a standard method of calculating the time to recovery. Estimation of incidence density using alternate methods performed well. The standard formula and method may provide an even better estimate of cumulative incidence than does simple prevalence in general populations.
Molecular Characterization of Methicillin-ResistantStaphylococcus aureusSpread by Neonates Transferred From Primary Obstetrics Clinics to a Tertiary Care Hospital in Korea
Authors: Ko Kwan Soo , Park Sulhee , Peck Kyong Ran , Shin Eun Jung , Oh Won Sup , Lee Nam Yong , Song Jae-Hoon 
Published: June 2006

Objective.To investigate the characteristics and origins of methicillin-resistantStaphylococcus aureus(MRSA) strains isolated from neonatal patients admitted to a tertiary care hospital from local and primary care obstetrics clinics.Design.Molecular typing study.Setting.A 1,278-bed tertiary care hospital (Samsung Medical Center) and 2 primary obstetrics clinics in Seoul, Korea.Patients.The genotypic characteristics of 12 MRSA samples isolated from 11 neonatal patients transferred from 2 primary care obstetrics clinics to a tertiary care hospital were investigated by means of multilocus sequence typing,spa(staphylococcal protein A) typing, andSCCmectyping. Ten MRSA strains isolated from workers and environments in the associated obstetrics clinics were also investigated.Results.Although the antibiograms of isolates from 2 obstetrics clinics differed, no strain showed multidrug resistance to antimicrobials. Multilocus sequence typing analysis showed that all 22 MRSA isolates analyzed in this study had sequence type 1 (with the allelic profile 1-1-1-1-1-1-1), sequence type 493 (62-1-1-1-1-1-1), or a novel sequence type (25-1-1-1-1-1-1) and that all belonged to a single clonal complex (clonal complex 1). Moreover, they all containedSCCmectype IVA and the identicalspatype (UJEBKBP). These genotypic characteristics are similar to those of typical community-associated MRSA strains rather than the hospital-acquired MRSA strains common in Korea.Conclusion.The findings of this study suggest that community-acquired MRSA strains can spread in primary care clinics and be imported into tertiary care settings.
Effect of Porosity on Thermal Stress Fracture
Authors: COBLE R. L. , KINGERY W. D. 
Published: June 2006

Sintered alumina with from 4 to 50% porosity was prepared by incorporating crushed naphthalene in a casting slip. Thermal stress resistance was determined from the radial temperature difference required to fracture hollow cylinders under steady‐state conditions. Thermal stress resistance decreases with increasing porosity; resistance to thermal stresses at 50% porosity is about one‐third of that estimated for zero porosity.Summary and ConclusionsSamples with controlled porosity were prepared by incorporating naphthalene flakes in an alumina casting slip. Samples were prepared and fired under identical conditions so that the continuous solid phase was identical for all samples. Steady‐state thermal stress tests described lead to the following conclusions:(1) Resistance to thermal stress, R (maximum steady‐state Δt for fracture), decreases with increasing porosity. The resistance for a sample with 50% porosity is about one‐third that for dense samples.(2) Resistance to thermal stress determined by the maximum heat flow permissible, R', decreases more rapidly than R because increasing porosity lowers the thermal conductivity. This factor for a sample with 50% porosity is about one‐sixth the value for dense samples. This is the factor generally applicable to thermal shock conditions.(3) Resistance to thermal fracture with a constant rate of surface temperature rise is directly proportional to R, since thermal diffusivity is unaffected by porosity.
Pressure Derivatives of the Sound Velocities of Polycrystalline Alumina
Authors: SCHREIBER EDWARD , ANDERSON ORSON L. 
Published: June 2006

The sound velocities and the pressure derivatives of the sound velocities were measured on a small specimen of polycrystalline alumina by the method of “pulse superposition”. The pressure derivatives found from experiments up to 4 kbars at 25°C are:
image
These values lead to the variation of Poisson's ratio with pressure of dσ/dP = 1.02 × 10−4/ kbar and to the variation of (isothermal) bulk modulus with pressure of dBT/dP= 3.99. Using the above values the compression is computed up to 400 kbars and compares well with shock wave measurements. Consequently, the measured pressure derivatives may hold up to several hundred kilobars.
The contribution of Bruce Glick to the definition of the role played by the bursa of Fabricius in the development of the B cell lineage
Authors: Ribatti D , Crivellato E , Vacca A 
Published: June 2006

SummaryIn 1956, Bruce Glick and Timothy Chang reported that the bursa of Fabricius plays an important role in antibody production. Their demonstration that antibody responses are suppressed in the majority of bursectomized chickens became the cornerstone of modern immunology. Bursa research increased considerably during the 1960s and early 1970s.
Role of the pro‐inflammatory cytokines TNF‐α and IL‐1β in HIV‐associated dementia
Authors: Brabers N. A. C. H. , Nottet H. S. L. M. 
Published: June 2006

AbstractHuman immunodeficiency virus‐1 (HIV‐1)‐infected and immune‐activated macrophages and microglia secrete neurotoxins. Two of these neurotoxins are the pro‐inflammatory cytokines tumour necrosis factor‐α (TNF‐α) and interleukin‐1β (IL‐1β), which are thought to play a major role in inducing neuronal death. Both TNF‐α and IL‐1β increase the permeability of the blood–brain barrier, through which subsequently HIV‐infected monocytes can enter the brain. They both induce over‐stimulation of the NMDA‐receptor via several pathways, resulting in a lethal neuronal increase in Ca2+levels. Additionally, TNF‐α co‐operates with several other proinflammatory mediators to enhance their toxic effects. Although most research has focused on the neurotoxic effects of TNF‐α and IL‐1β in HAD, there is also evidence that these cytokines can be neuroprotective. In this paper the effect of TNF‐α and IL‐1β on neuronal life and death in HAD is discussed.
Innovation in anti‐herbivore defense systems during neopolypoloidy – the functional consequences of instantaneous speciation
Authors: Pearse Ian S. , Krügel Tamara , Baldwin Ian T. 
Published: June 2006

SummaryAllopolyploid hybridization instantly merges two differentially adapted genomes into one individual. Allopolyploids are often evolutionarily successful, undergoing adaptive radiations despite the genetic and physiological challenges of merging genomes. We examine a suite of induced herbivore resistance traits in three independent lines of the synthetic allopolyploidNicotiana×mierata(Nma) and its parent species,N. miersii(Nmi) andN. attenuata(Na), to determine how a complex polygenetic adaptation fares during the early stages of neoallopolyploid formation. All species responded toManduca sextaoral secretions (OS) with a temporally prolonged jasmonate (JA) burst. In one parent (Na), the JA burst was additionally amplified and associated with the elicitation of direct and indirect defenses. In the other parent (Nmi), OS neither amplified the JA burst nor elicited defense responses, although applied MeJA confirmed the inducibility of the defense responses. All lines ofNmaretained enough aspects ofNa’s JA signaling to recognize OS and to accumulate sufficient direct defenses to impair the growth ofManducalarvae. Most defense‐related metabolites were retained inNmaeven if inherited from only one parent; however, OS‐elicited volatiles, trypsin protease inhibitors (TPIs) and chlorogenic acid were lost in some lines, even though MeJA treatment elicited similar responses in all lines. Herbivore defense systems are flexibly inherited in allopolyploids, causing individuals to diverge over only a few generations; for example, line 1 ofNmacould not produce TPIs after OS elicitation, whereas lines 2 and 3 could. This flexible integration of defense signaling systems with a diversity of elicited responses may explain why adaptive radiations are commonly found in allopolyploid lineages.
Maize mutants affected at distinct stages of the arbuscular mycorrhizal symbiosis
Authors: Paszkowski Uta , Jakovleva Ludmila , Boller Thomas 
Published: June 2006

SummaryMaize mutants affected in the symbiotic interaction with the arbuscular mycorrhizal fungus Glomus mosseae have been found by a visual, macroscopic screen in a Mutator‐tagged population of maize. Seven mutants have been identified, falling into three phenotypic classes. For each class one mutant has been characterized in more detail. The nope1 (noperception 1) mutant does not support appressoria formation of G. mosseae, suggesting the absence of a plant‐encoded function necessary for early recognition prior to contact. The phenotype segregated as a monogenic recessive trait, indicating that a mutation in a single locus abolished compatibility of maize to G. mosseae. On a second mutant termed taci1 (taciturn 1), appressoria form at reduced frequency but their morphology is normal and leads to penetration of the rhizodermis. However, intraradically, the majority of hyphae are septate, resulting in terminated fungal spreading. This phenotype suggests that the mutation of taci1 has an effect on recognition and on cortex invasion. Segregation analysis indicates taci1 to carry a recessive mutation. In contrast, wild‐type fungal morphology has been recorded in the Pram1 (Precocious arbuscular mycorrhiza 1) mutant, which displays enhanced and earlier fungal invasion. This trait segregates in a dominant fashion indicative of a gain‐of‐function mutation affecting the plant's control over restricting fungal colonization.
Risk factors for chickenpox incidence in Taiwan from a large‐scale computerized database
Authors: Wu Po‐yuan , Li Yu‐Chuan , Wu Hong‐Dar Isaac 
Published: June 2006

AbstractObjective  We analyzed data from the National Health Insurance Research (NHIR) database in the year 2000 to estimate the seasonal variation in the chickenpox rate in Taiwan.Patients and Methods  All chickenpox cases listed in the NHIR database were included (n = 165,719). A Lorenz curve was plotted and a chi‐square test for equal proportions calculated for seasonal variation. To determine the effects of temperature and season on outcome values, generalized estimating equation methods were utilized to adjust the effects of other possible influencing factors and take into account the within‐subject dependence over repeated assessments.Results  All four regions of the country had highest incidence rates in January, and three of them had lowest rates in September. Incidence was significantly higher in females aged 15–24 years than in males. An increment of 1 °C resulted in an incidence ratio of approximately 0.98 or, equivalently, a 10 °C increment gives an incidence ratio of approximately 0.78.Conclusion  The results suggest that season and temperature are significantly related to the incidence of chickenpox. Infectious diseases can be monitored. Prevention procedures can be taken by understanding its pattern and activity in order to decide the best policy for vaccination. Further studies are warranted, particularly for long‐term trends, and in other nations with different seasonal temperatures from Taiwan.