bluuebunny/crossref_metadata_2025 huggingface dataset:
Predation by red fox on European roe deer fawns in relation to age, sex, and birth date
Authors: Jarnemo Anders , Liberg Olof , Lockowandt Steffan , Olsson Agneta , Wahlström Kjell
Published: June 2004

Mortality in radio-marked European roe deer (Capreolus capreolus (Linnaeus, 1758)) neonates was studied during 14 years in a mixed forestagricultural landscape in Sweden. A total of 233 fawns were marked. Births were synchronized, with 79% occurring during 25 days and a peak between 25 May and 7 June encompassing 62% of the births. Overall mortality was 42%, but in three single years, it exceeded 85%. Predation by red fox (Vulpes vulpes Desmarest, 1820) accounted for 81% of total mortality. The effects of age, sex, and time of birth on the vulnerability to predation were analysed. Fawns born just after the birth peak had the lowest predation risk. Predation rate was highest for the fawns that had the very earliest or the very latest birth dates. Predation thereby seems to strengthen the birth synchrony in roe deer. Contrary to earlier published findings, there was no difference in susceptibility to predation between the sexes. Also differing from earlier findings was that predation rate was highest during the first week of life and declined thereafter almost linearly. The majority of the fawns (85%) were killed before 30 days of age and 98% before 40 days. Different types of landscapes may explain the discrepancies between our study and earlier findings.
Use of naturally occurring mercury to determine the importance of cutthroat trout to Yellowstone grizzly bears
Authors: Felicetti Laura A , Schwartz Charles C , Rye Robert O , Gunther Kerry A , Crock James G , Haroldson Mark A , Waits Lisette , Robbins Charles T
Published: June 2004

Spawning cutthroat trout (Oncorhynchus clarki (Richardson, 1836)) are a potentially important food resource for grizzly bears (Ursus arctos horribilis Ord, 1815) in the Greater Yellowstone Ecosystem. We developed a method to estimate the amount of cutthroat trout ingested by grizzly bears living in the Yellowstone Lake area. The method utilized (i) the relatively high, naturally occurring concentration of mercury in Yellowstone Lake cutthroat trout (508 ± 93 ppb) and its virtual absence in all other bear foods ([Formula: see text]6 ppb), (ii) hair snares to remotely collect hair from bears visiting spawning cutthroat trout streams between 1997 and 2000, (iii) DNA analyses to identify the individual and sex of grizzly bears leaving a hair sample, (iv) feeding trials with captive bears to develop relationships between fish and mercury intake and hair mercury concentrations, and (v) mercury analyses of hair collected from wild bears to estimate the amount of trout consumed by each bear. Male grizzly bears consumed an average of 5 times more trout/kg bear than did female grizzly bears. Estimated cutthroat trout intake per year by the grizzly bear population was only a small fraction of that estimated by previous investigators, and males consumed 92% of all trout ingested by grizzly bears.
A potential cost of responding to bats for moths flying over water
Authors: Guignion Cassandra , Fullard James H
Published: June 2004

Although the evasive flight of eared moths to attacking bats has received much attention in the literature, no studies have been made of the potential costs for this behaviour. We examined the fate of moths that land upon the surface of a lake in a simulation of an evasive power dive away from a bat. Of 102 different-sized moths from 18 species that were dropped onto the surface of a lake in eastern Ontario, Canada, 61% were eaten, on average, by fish in 31.3 s with no effect of wing surface area on escape success. These results suggest that nocturnal predation on moths by fish may be underestimated and that this behaviour may cause moths to avoid lakes when flying.
Diet reconstruction of ancient brown bears (Ursus arctos) from Mont Ventoux (France) using bone collagen stable isotope biogeochemistry (13C,15N)
Authors: Bocherens Hervé , Argant Alain , Argant Jacqueline , Billiou Daniel , Crégut-Bonnoure Evelyne , Donat-Ayache Bernadette , Philippe Michel , Thinon Michel
Published: June 2004

A very rich assemblage of ancient brown bears (Ursus arctos arctos Linnaeus, 1758) from Mont Ventoux caves (France) has been investigated using carbon and nitrogen isotopic composition of bone collagen. The isotopic data showed that these bears were feeding in an open environment and consumed mainly plant food items. The access to livestock meat appeared to have been much more limited for these ancient brown bears than for 20th-century Pyrenean bears, suggesting that husbandry patterns had kept bears away from domestic herds. The isotopic variations observed are large according to the ontogenic stage of the bears when they died, which could be accounted for by the isotopic changes that occur during hibernation of the lactating female bear and by different time periods averaged in bone collagen, and without the need to involve different food resources for cubs relative to adult bears.
Effects of pH and dilution on African clawed frog (Xenopus laevis) sperm motility
Authors: Christensen Jennie R , Pauli Bruce D , Richardson John S , Bishop Christine A , Elliott John
Published: June 2004

Effects of pH and dilution on sperm motility were examined using the African clawed frog, Xenopus laevis (Daudin, 1802), as a model species. Sperm removed from adult X. laevis males were stored on ice in DeBoer's solution, rendering them immotile until activation by dilution. A series of pHs ranging from 5.5 to 7.8 and a dilution series ranging from 1:1 to 5:1 (diluent : sperm solution) were examined. Motility was assessed by constructing sperm track maps for individual spermatozoa using video recordings. pH did not significantly affect the percentage of spermatozoa with motility; however, pH 7.0 produced observably higher motility than other pH treatments. Velocities and velocity ratios were not significantly affected by the various pH treatments. A solution with a 3:1 dilution ratio resulted in the highest percentage of sperm with motility (55.3 ± 8.5%) and the highest curvilinear velocity (approximately 65 µm/s). Average path velocity, as well as the linearity and wobble of the sperm track, were also significantly affected by dilution. The results indicate that the chemistry of the freshwater environment in which X. laevis sperm must swim to the eggs may be important for successful fertilization to take place.
Forage selection by collared pikas,Ochotona collaris, under varying degrees of predation risk
Authors: Morrison Shawn , Barton Luc , Caputa Peter , Hik David S
Published: June 2004

The effects of predation risk on foraging behavior often result in a trade-off between obtaining food and seeking shelter and may alter the selectivity of herbivores for individual plant species. We experimentally measured forage selection by a small alpine herbivore, the collared pika (Ochotona collaris (Nelson, 1893)), using a cafeteria-style arrangement of six potential forage species at five levels of predation risk. Contrary to our prediction, haying pikas did not switch preferences for forage species of different nutritional quality as predation risk increased. However, the total amount of forage removed was inversely related to risk, and the addition of cover at treatments of greatest potential risk ameliorated the negative effects of higher predation risk. The reasons for increased preference for poorer quality forage species in 2002 relative to 2000 are currently unknown but may reflect changes in predator abundance, forage quality, or increased competition for limited forage resources.
Age-specific survival, abundance, and immigration rates of a Weddell seal (Leptonychotes weddellii) population in McMurdo Sound, Antarctica
Authors: Cameron Michael F , Siniff Donald B
Published: June 2004

Since the 1960s, Weddell seals (Leptonychotes weddellii (Lesson, 1826)) have been tagged and surveyed annually in McMurdo Sound, Antarctica. Markrecapture analyses and model selection trials using Akaike's Information Criterion indicate that sex, cohort, and year affect juvenile (ages 1 and 2) survival. In contrast, year and perhaps sex and cohort are less important factors for adult survival. Average annual survival is higher among adults (0.93) than juveniles (0.550.59) and there is little evidence for senescence to at least age 17. The oldest known-aged female and male in the study were 27 and 24 years old, respectively. Data suggest that the abundance of a resident population of Weddell seals remains relatively stable over time despite annual fluctuations in JollySeber abundance estimates for the entire population. We argue that this annual variability is likely the result of temporary immigration of animals born outside the study area; mean rates are estimated from a simulation model and tagging data to be between 16.8% and 39.7% for females and between 13.1% and 31.6% for males. Sea ice extent appears to affect immigration where, during times of reduced fast-ice, immigrants are forced, or allowed easier access, into the ice-covered areas of Erebus Bay from surrounding locations. Our findings contradict previous studies reporting lower survival and higher immigration. Model choice is shown to be the most likely cause of these discrepancies and we provide evidence that our models are more appropriate than those used elsewhere.
Effect of a colour dimorphism on the flower constancy of honey bees and bumble bees
Authors: Gegear Robert J , Laverty Terence M
Published: June 2004

We assessed the flower constancy of Italian honey bees (Apis mellifera ligustica Spinelli, 1808) and bumble bees (Bombus impatiens Cresson, 1863) by presenting individual foragers with a mixed array of equally rewarding yellow and blue flowers after they were trained to visit each colour in succession. All honey bees showed a high degree of flower constancy to one colour and rarely visited the alternate colour, whereas most bumble bees indiscriminately visited both colours. Foraging rates (flowers visited per minute) and flower handling times did not differ between honey bee and bumble bee foragers; however, bumble bees tended to fly farther between consecutive flower visits and make fewer moves to nearest neighbouring flowers than honey bees. When bees were forced to specialize on one of two previously rewarding flower colours by depleting one colour of reward, honey bees required almost twice as many flower visits to specialize on the rewarding flower colour as bumble bees. Together, these results suggest that the relationship between individual flower constancy and colour differences is not a general behavioural phenomenon in honey and bumble bees, perhaps because of differences in the ability of each group to effectively manage multiple colours at the same time and location.
Condition-dependent behaviour among damselfly populations
Authors: Mikolajewski Dirk Johannes , Johansson Frank , Brodin Tomas
Published: June 2004

Body condition is predicted to influence behaviours such as activity, which in turn affects energy gain and survival. In this study we investigated (i) whether populations of the damselfly Lestes sponsa (Hansemann, 1823) differ in body condition and activity among lakes, and (ii) which body condition factors affect behaviour. We estimated last instar larval behaviour (measured as activity), body condition (measured as size, body mass, muscle mass, fat content, and time to emergence), and fish presence/absence in eight lakes. Body condition of larvae differed among lakes but the presence/absence of fish in lakes had no effect on body condition. Activity did not differ among lakes and was not affected by the presence/absence of fish in lakes. Activity was negatively related to size, body mass, muscle mass, and fat content, and positively related with time to emergence, suggesting that final-instar larvae in good condition are favouring development over growth to emerge earlier. This study highlights the importance of differences in condition among populations and among individuals.
Skeletal muscle contraction stimulates capillary recruitment and glucose uptake in insulin-resistant obese Zucker rats
Authors: Wheatley Catherine M. , Rattigan Stephen , Richards Stephen M. , Barrett Eugene J. , Clark Michael G.
Published: June 2004

Exercise and insulin increase muscle glucose uptake by different mechanisms and also increase capillary recruitment, which is proposed to facilitate access for hormones and nutrients. The genetically obese Zucker rat shows impaired insulin- but not contraction-mediated glucose uptake in muscle. Recently, we have shown the genetically obese Zucker rats to have impaired insulin-mediated capillary recruitment and proposed that this contributes to the insulin resistance of muscle in vivo. Because this might imply a general loss of recruitable capillaries, we now assess responses to contraction in muscles of 18 ± 3-wk-old lean and obese Zucker rats in vivo. Field stimulation (2 Hz, 0.1 ms) was conducted for 1 h on one leg of anesthetized instrumented rats, and measurements were made of femoral blood flow (FBF), heart rate (HR), blood pressure (BP), hindleg metabolism of 1-methylxanthine (a measure of capillary recruitment), hindleg glucose uptake (HGU), and lower leg muscle glucose uptake by 2-deoxyglucose (R′g). Lean animals (311 ± 9 g) developed tension at 219 ± 27 g/g muscle with no change in BP but with significant increases in HR, FBF, HGU, 1-MX metabolism, and R′g ( P < 0.05), compared with nonstimulated control leans. Obese animals (469 ± 7 g) developed tension at 265 ± 31 g/g muscle with no change in HR or BP but with significant increases in FBF, HGU, 1-MX metabolism, and R′g ( P < 0.05) compared with nonstimulated control obese rats. Muscle contraction of lean animals led to a greater increase in lower leg R′g, similar responses in HGU and 1-MX, and a smaller increase in FBF than in obese animals. A tight correlation between FBF and capillary recruitment was noted for all data ( P < 0.001). It is concluded that contraction-mediated muscle capillary recruitment and glucose uptake are essentially normal in the obese Zucker rat and that control of FBF and capillary recruitment in exercise is closely linked.
Spatial Transformations for Eye–Hand Coordination
Authors: Crawford J. D. , Medendorp W. P. , Marotta J. J.
Published: June 2004

Eye–hand coordination is complex because it involves the visual guidance of both the eyes and hands, while simultaneously using eye movements to optimize vision. Since only hand motion directly affects the external world, eye movements are the slave in this system. This eye– hand visuomotor system incorporates closed-loop visual feedback but here we focus on early feedforward mechanisms that allow primates to make spatially accurate reaches. First, we consider how the parietal cortex might store and update gaze-centered representations of reach targets during a sequence of gaze shifts and fixations. Recent evidence suggests that such representations might be compared with hand position signals within this early gaze-centered frame. However, the resulting motor error commands cannot be treated independently of their frame of origin or the frame of their destined motor command. Behavioral experiments show that the brain deals with the nonlinear aspects of such reference frame transformations, and incorporates internal models of the complex linkage geometry of the eye–head–shoulder system. These transformations are modeled as a series of vector displacement commands, rotated by eye and head orientation, and implemented between parietal and frontal cortex through efficient parallel neuronal architectures. Finally, we consider how this reach system might interact with the visually guided grasp system through both parallel and coordinated neural algorithms.
New Vistas on Amygdala Networks in Conditioned Fear
Authors: Paré Denis , Quirk Gregory J. , Ledoux Joseph E.
Published: June 2004

It is currently believed that the acquisition of classically conditioned fear involves potentiation of conditioned thalamic inputs in the lateral amygdala (LA). In turn, LA cells would excite more neurons in the central nucleus (CE) that, via their projections to the brain stem and hypothalamus, evoke fear responses. However, LA neurons do not directly contact brain stem-projecting CE neurons. This is problematic because CE projections to the periaqueductal gray and pontine reticular formation are believed to generate conditioned freezing and fear-potentiated startle, respectively. Moreover, like LA, CE may receive direct thalamic inputs communicating information about the conditioned and unconditioned stimuli. Finally, recent evidence suggests that the CE itself may be a critical site of plasticity. This review attempts to reconcile the current model with these observations. We suggest that potentiated LA outputs disinhibit CE projection neurons via GABAergic intercalated neurons, thereby permitting associative plasticity in CE. Thus plasticity in both LA and CE would be necessary for acquisition of conditioned fear. This revised model also accounts for inhibition of conditioned fear after extinction.
The second‐order self‐associated orthogonal sequences
Authors: Maroni P. , Tounsi M. Ihsen
Published: June 2004

The aim of this work is to describe the orthogonal
polynomials sequences which are identical to their second
associated sequence. The resulting polynomials are semiclassical
of class s ≤ 3. The characteristic elements of the structure
relation and of the second‐order differential equation are given
explicitly. Integral representations of the corresponding forms
are also given. A striking particular case is the case of the
so‐called electrospheric polynomials.
Fatality of Future Coronary Events Is Related to Inflammation-Sensitive Plasma Proteins
Authors: Engström Gunnar , Hedblad Bo , Stavenow Lars , Tydén Patrik , Lind Peter , Janzon Lars , Lindgärde Folke
Published: June 2004

Background—

Approximately 40% of men suffering a first acute coronary event die the first day; most of them never reach hospital. It is largely unknown whether a low-grade inflammation in healthy men predicts the fatality of future coronary events.

Methods and Results—

Five inflammation-sensitive plasma proteins (ISPs; fibrinogen, orosomucoid, α
1
-antitrypsin, haptoglobin, and ceruloplasmin) were measured in 6075 apparently healthy men, 680 of whom had a first coronary event [nonfatal myocardial infarction (MI) or death from coronary heart disease (CHD)] over a mean follow-up of 19 years. Of the 680 men who had a coronary event, 197 died the first day and 228 died within 28 days. Elevated ISPs were significantly associated with both nonfatal MI and CHD death, but the relative risks for CHD death were higher than for nonfatal MI. Among men who subsequently had a coronary event, the proportion of fatal events was related to the number of elevated ISPs at the baseline examination. The proportions who died the first day were 26%, 25%, 29%, and 35%, respectively, among men with 0, 1, 2, and ≥3 elevated ISPs (trend:
P
=0.01, adjusted for risk factors). The corresponding proportions who died within 28 days were 30%, 31%, 34%, and 38%, respectively (trend:
P
=0.03).

Conclusions—

Men who have been exposed to a low-grade inflammation many years earlier have higher fatality in future coronary events, with a higher proportion of CHD deaths and less nonfatal MI. This relation should be regarded when inflammatory markers are considered for risk assessment in primary prevention.
Relationship Between Erectile Dysfunction and Silent Myocardial Ischemia in Apparently Uncomplicated Type 2 Diabetic Patients
Authors: Gazzaruso Carmine , Giordanetti Stefano , De Amici Emanuela , Bertone Gianandrea , Falcone Colomba , Geroldi Diego , Fratino Pietro , Solerte Sebastiano B. , Garzaniti Adriana
Published: June 2004

Background—

Erectile dysfunction (ED) is associated with coronary artery disease (CAD). In diabetic patients, CAD is often silent. Among diabetic patients with silent CAD, the prevalence of ED has never been evaluated. We investigated whether ED is associated with asymptomatic CAD in type 2 diabetic patients.

Methods and Results—

We evaluated the prevalence of ED in 133 uncomplicated diabetic men with angiographically verified silent CAD and in 127 diabetic men without myocardial ischemia at exercise ECG, 48-hour ambulatory ECG, and stress echocardiography. The groups were comparable for age and diabetes duration. Patients were screened for ED using the validated International Index of Erectile Function (IIEF-5) questionnaire. The prevalence of ED was significantly higher in patients with than in those without silent CAD (33.8% versus 4.7%;
P
=0.000). Multiple logistic regression analysis showed that ED, apolipoprotein(a) polymorphism, smoking, microalbuminuria, HDL, and LDL were significantly associated with silent CAD; among these risk factors, ED appeared to be the most efficient predictor of silent CAD (OR, 14.8; 95% CI, 3.8 to 56.9).

Conclusions—

Our study first shows a strong and independent association between ED and silent CAD in apparently uncomplicated type 2 diabetic patients. If our findings are confirmed, ED may become a potential marker to identify diabetic patients to screen for silent CAD. Moreover, the high prevalence of ED among diabetics with silent CAD suggests the need to perform an exercise ECG before starting a treatment for ED, especially in patients with additional cardiovascular risk factors.
Very Low Levels of Microalbuminuria Are Associated With Increased Risk of Coronary Heart Disease and Death Independently of Renal Function, Hypertension, and Diabetes
Authors: Klausen Klaus , Borch-Johnsen Knut , Feldt-Rasmussen Bo , Jensen Gorm , Clausen Peter , Scharling Henrik , Appleyard Merete , Jensen Jan Skov
Published: June 2004

Background—

The aim of this study was to assess the level of urinary albumin excretion (microalbuminuria), which is associated with increased risk of coronary heart disease and death, in the population. Microalbuminuria has been suggested as an atherosclerotic risk factor. However, the lower cutoff level of urinary albumin excretion is unknown. It is also unknown whether impaired renal function confounds the association.

Methods and Results—

In the Third Copenhagen City Heart Study in 1992 to 1994, 2762 men and women 30 to 70 years of age underwent a detailed cardiovascular investigation program, including a timed overnight urine sample. The participants were then followed up prospectively by registers until 1999 with respect to coronary heart disease and until 2001 with respect to death. During follow-up, 109 incident cases of coronary heart disease and 276 deaths were traced. A urinary albumin excretion above the upper quartile, ie, 4.8 μg/min, was associated with increased risk of coronary heart disease (RR, 2.0; 95% CI, 1.4 to 3.0;
P
<0.001) and death (RR, 1.9; 95% CI, 1.5 to 2.4;
P
<0.001) independently of age, sex, renal creatinine clearance, diabetes mellitus, hypertension, and plasma lipids. Lower levels of urinary albumin excretion were not associated with increased risk.

Conclusions—

Microalbuminuria, defined as urinary albumin excretion >4.8 μg/min (corresponding to ≈6.4 μg/min during daytime), is a strong and independent determinant of coronary heart disease and death. Our suggestion is to redefine microalbuminuria accordingly and perform intervention studies.
Selective Inhibition of Protein Kinase Cβ
2
Prevents Acute Effects of High Glucose on Vascular Cell Adhesion Molecule-1 Expression in Human Endothelial Cells
Authors: Kouroedov Alexei , Eto Masato , Joch Hana , Volpe Massimo , Lüscher Thomas F. , Cosentino Francesco
Published: June 2004

Background—

Enhanced expression of adhesion molecules by the endothelium may account for vascular damage in diabetics and nondiabetic patients who develop stress hyperglycemia during acute myocardial infarction. We analyzed the phosphorylation of protein kinase Cβ
2
(PKCβ
2
) at serine/threonine residues, which may contribute to the endothelial dysfunction during acute hyperglycemia. Furthermore, this study was designed to investigate whether selective blockade of this regulatory mechanism may prevent the development of endothelial hyperadhesiveness.

Methods and Results—

Incubation of the human aortic endothelial cells with high glucose (22.2 mmol/L) resulted in significant increase of vascular cell adhesion molecule (VCAM)-1 protein expression (172±15% versus control;
P
<0.01). Phorbol 12-myristate 13-acetate, a potent activator of PKC, mimicked the effect of high glucose on VCAM-1 expression. High glucose led to a rapid increase (181±22% versus control;
P
<0.01) of membrane-bound PKCβ, reflecting activation of this enzyme. The nonselective inhibitor of PKCβ
1
and PKCβ
2
isoforms LY379196, as well as CGP53353, a highly selective inhibitor of PKCβ
2
, prevented in a dose-dependent manner upregulation of VCAM-1. Incubation with high glucose was associated with increased PKCβ
2
phosphorylation at the Ser-660 residue, and both LY379196 and CGP53353 prevented this event. Exposure of the cells to high glucose also reduced the protein level of the inhibitory subunit of nuclear factor-κB, IκBα, leading to its enhanced binding activity. Selective inhibition of PKCβ abolished IκBα degradation.

Conclusions—

Our findings demonstrate for the first time that phosphorylation of Ser-660 represents a selective regulatory mechanism for glucose-induced upregulation of VCAM-1. Therefore, PKCβ
2
-selective inhibitors may be promising drugs for treatment of endothelial dysfunction during acute hyperglycemia and possibly in diabetes.
Magnetic Resonance Versus Radionuclide Pharmacological Stress Perfusion Imaging for Flow-Limiting Stenoses of Varying Severity
Authors: Lee Daniel C. , Simonetti Orlando P. , Harris Kathleen R. , Holly Thomas A. , Judd Robert M. , Wu Edwin , Klocke Francis J.
Published: June 2004

Background—

Although magnetic resonance first-pass imaging (MRFP) has potential advantages in pharmacological stress perfusion imaging, direct comparisons of current MRFP and established radionuclide techniques are not available.

Methods and Results—

Graded regional differences in coronary flow were produced during global coronary vasodilation in chronically instrumented dogs by partially occluding the left circumflex artery. Regional differences in full-thickness flow quantified using microspheres were compared with regional differences obtained with MRFP and radionuclide SPECT imaging (
99m
Tc-sestamibi and
201
Tl). Relative regional flows (RRFs) derived from the initial areas under MRFP signal intensity-time curves were linearly related to reference microsphere RRFs over the full range of vasodilation (y=0.93x+4.3;
r
2
=0.77). Relationships between
99m
Tc-sestamibi and
201
Tl RRFs and microsphere RRFs were curvilinear, plateauing as flows increased. The high spatial resolution of the MRI enabled transmural flow to be evaluated in 3 to 5 layers across the myocardial wall. Reductions in subendocardial flow were visually apparent in MRFP images for ≥50% reductions in full-thickness flow. Endocardial-to-epicardial gradients in MRFP flow increased progressively with stenosis severity, whereas transmural flow patterns in remote normally perfused myocardium remained normal. Flow reductions of ≥50% not identified by radionuclide imaging were apparent in MRFP full-thickness and transmural analyses.

Conclusions—

High-resolution MRFP can identify regional reductions in full-thickness myocardial blood flow during global coronary vasodilation over a wider range than current SPECT imaging. Transmural flow gradients can also be identified; their magnitude increases progressively as flow limitations become more severe and endocardial flow is compromised increasingly.
Abnormal Carotid Artery Structure and Function in Children and Adolescents With Successful Renal Transplantation
Authors: Mitsnefes Mark M. , Kimball Thomas R. , Witt Sandra A. , Glascock Betty J. , Khoury Philip R. , Daniels Stephen R.
Published: June 2004

Background—

Abnormal carotid artery compliance and increased intima-media thickness (IMT), markers of early atherosclerosis, are prevalent in adults with chronic kidney failure. However, little is known about the extent of these abnormalities in children after transplantation.

Methods and Results—

Thirty-one children (age, 14.5±4.1 years) with renal transplant (estimated glomerular filtration rate, 78.1±24.5 mL/min per 1.73 m
2
; range, 44 to 128 mL/min per 1.73 m
2
) and 33 age- and sex-matched control subjects had ultrasound of the carotid artery, echocardiography, and ambulatory blood pressure monitoring (transplant patients only). IMT was measured, and distensibility and stiffness parameter (β) were calculated to assess carotid artery structure and function. The results were correlated with demographic, clinical, and biochemical variables. Compared with control subjects, children with transplant had higher IMT (
P
=0.03) and β (
P
<0.0001) and lower distensibility (
P
<0.001). In multiple regression analysis, increased IMT in children who had received transplants was associated with higher mean office systolic blood pressure taken within 1 year before the study (
R
2
=0.19,
P
=0.024) and receipt of >1 transplant (
R
2
=0.16,
P
=0.02). Worse distensibility and β were significantly associated with higher daytime systolic blood pressure load calculated from ambulatory blood pressure and receipt of cadaveric kidney. When number of antihypertensives was added to the models, only higher number of blood pressure medications independently predicted abnormal distensibility (
R
2
=0.38,
P
=0.002) and β (
R
2
=0.25,
P
=0.016).

Conclusions—

Carotid arteriopathy is present in children with successful renal transplant and is associated with hypertension. The results suggest that these children might be at risk for accelerated atherosclerosis and premature cardiovascular disease.
Extracellular Calcium and Vascular Responses After Forearm Ischemia
Authors: Imadojemu Virginia A. , Mooney Kenneth , Hogeman Cindy , Lott Mary E.J. , Kunselman Allen , Sinoway Lawrence I.
Published: June 2004

Background—

The myogenic response is a phenomenon in which blood vessels respond to increases and decreases in transmural pressure with constriction and dilation, respectively. Despite intense investigation into the signaling mechanisms underlying this response, the precise mechanisms remain unclear. It has been suggested that the myogenic response occurs when pressure or stretch evokes increases in vessel wall tension that results in vessel smooth muscle cell depolarization. This causes Ca
2+
entry through voltage-gated Ca
2+
channels. Of note, in vitro studies demonstrate that the magnitude of the myogenic response is dependent on the extracellular Ca
2+
. We tested the hypothesis that in conscious humans, physiological changes in extracellular Ca
2+
concentrations would be an important determinant of the myogenic response.

Methods and Results—

Venous blood ionized calcium was used as an index of interstitial calcium and was measured 5, 15, and then every 15 seconds for 75 seconds, then every 30 seconds for 90 seconds, then finally at the 300-second mark. Forearm blood pressure and flow velocity were determined after 10 minutes of forearm ischemia. We found that the rate of change in serum calcium levels varied as a function of transmural pressure (
r
=0.96). Moreover, the calcium concentration was inversely proportional to forearm blood velocity (
r
=0.99).

Conclusions—

We hypothesize that muscle stretch caused by a rise in transmural pressure raises interstitial calcium by unknown mechanisms and this in turn acts to lower limb flow velocity.
Parathyroid Hormone–Related Protein as a Regulator of pRb and the Cell Cycle in Arterial Smooth Muscle
Authors: Fiaschi-Taesch Nathalie , Takane Karen K. , Masters Sophia , Lopez-Talavera Juan Carlos , Stewart Andrew F.
Published: June 2004

Background—

Parathyroid hormone–related protein (PTHrP), a normal product of arterial vascular smooth muscle (VSM), contains a nuclear localization signal (NLS) and at least 2 translational initiation sites, one that generates a conventional signal peptide and one that disrupts the signal peptide. These unusual features allow PTHrP either to be secreted in a paracrine/autocrine fashion, and thereby to inhibit arterial smooth muscle proliferation, or to be retained within the cytosol and to translocate into the nucleus, thereby serving as an intracrine stimulator of smooth muscle proliferation.

Methods and Results—

Here, we demonstrate 2 important findings. First, PTHrP dramatically increases the percentage of VSM cells in the S and in G
2
/M phases of the cell cycle. These effects require critical serine and threonine residues at positions Ser
119
, Ser
130
, Thr
132
, and Ser
138
in the carboxy-terminus of PTHrP and are associated with the phosphorylation of the key cell cycle checkpoint regulator retinoblastoma protein, pRb. Second, because PTHrP devoid of the NLS serves as an inhibitor of VSM proliferation, we hypothesized that local delivery of NLS-deleted PTHrP to the arterial wall at the time of angioplasty might prevent neointimal hyperplasia. As hypothesized, using a rat carotid angioplasty model, adenoviral delivery of NLS-deleted PTHrP completely abolished the development of the neointima after angioplasty.

Conclusions—

PTHrP interacts with key cell cycle regulatory pathways within the arterial wall. Moreover, NLS-deleted PTHrP delivered to the arterial wall at the time of angioplasty seems to have promise as an agent that could reduce or eliminate the neointimal response to angioplasty.
Molecular Imaging of Factor XIIIa Activity in Thrombosis Using a Novel, Near-Infrared Fluorescent Contrast Agent That Covalently Links to Thrombi
Authors: Jaffer Farouc A. , Tung Ching-Hsuan , Wykrzykowska Joanna J. , Ho Nan-Hui , Houng Aiilyan K. , Reed Guy L. , Weissleder Ralph
Published: June 2004

Background—

Activated factor XIII (FXIIIa) mediates fibrinolytic resistance and is a hallmark of newly formed thrombi. In vivo imaging of FXIIIa activity could further elucidate the role of this molecule in thrombosis and other biological processes and aid in the clinical detection of acute thrombi.

Methods and Results—

An FXIIIa-sensitive near-infrared fluorescence imaging agent (A15) was engineered by conjugating a near-infrared fluorochrome to a peptide ligand derived from the amino terminus of α
2
-antiplasmin. To evaluate the molecular specificity of A15 for FXIIIa, a control agent (C15) was also synthesized by modifying a single key glutamine residue in A15. Fluorescence imaging experiments with A15 demonstrated stronger thrombosis enhancement in human plasma clots in vitro (
P
<0.001 versus C15 clots and other controls). A15 was found to be highly specific for the active site of FXIIIa and was covalently bound to fibrin. In vivo murine experiments with A15 demonstrated significant signal enhancement in acute intravascular thrombi (
P
<0.05 versus C15 group). Minimal A15 enhancement was seen in older aged thrombi (>24 hours), consistent with an expected decline of FXIIIa activity over time. Imaging results were confirmed on correlative histopathology and fluorescence microscopy.

Conclusions—

A15 is a novel optical imaging agent that is specifically crosslinked to fibrin by FXIIIa, permitting detection of FXIIIa activity in experimental thrombi in vivo. This agent should permit assessment of FXIIIa activity in a broad range of biological processes and could aid in the clinical diagnosis of acute thrombi.
Genome-Wide Scan for Pulse Pressure in the National Heart, Lung and Blood Institute’s Framingham Heart Study
Authors: DeStefano Anita L. , Larson Martin G. , Mitchell Gary F. , Benjamin Emelia J. , Vasan Ramachandran S. , Li Jiang , Corey Diane , Levy Daniel
Published: June 2004

The objective of this study was to assess heritability and identify chromosomal regions showing evidence of linkage to pulse pressure (PP), a simple indicator of proximal conduit vessel stiffness. Blood pressure data were analyzed for 8478 members of the National Heart, Lung and Blood Institute’s (NHLBI) Framingham Heart Study. Long-term PP was defined using 2-stage analysis. First, the difference between systolic and diastolic blood pressure was averaged over all qualifying clinic examinations. In the second stage, mean PP was adjusted for mean age, time period of examination, and body mass index by regression analysis. PP values were available for 6421 individuals in 1593 families for heritability estimation and for 2492 individuals in 330 families for linkage analysis. Microsatellite markers covering the genome at 10 cM intervals were typed by the NHLBI Mammalian Genotyping Service; genome scan data were available on 1585 individuals with PP data. Heritability estimates of long-term PP accounting for hypertension treatment and for ignoring treatment were 0.52 and 0.51, respectively. Variance component linkage analysis identified several locations with suggestive evidence of linkage: chromosome 15 at 122 cM (logarithm of odds [LOD]=2.94), chromosome 7 at 71 cM (LOD=2.42), chromosome 5 at 53 cM (LOD=2.03), and chromosome 10 at 81 cM (LOD=1.83) for PP accounting for treatment. LOD scores were slightly lower when ignoring treatment, with the exception of a peak on chromosome 10 at 81 cM (LOD=2.58). In conclusion, we have demonstrated a substantial genetic component to PP and have identified 4 chromosomal regions that may harbor genes influencing vascular stiffness.
Prevalence and Clinical Significance of Isolated Ambulatory Hypertension in Young Subjects Screened for Stage 1 Hypertension
Authors: Palatini Paolo , Winnicki Mikolaj , Santonastaso Massimo , Mos Lucio , Longo Daniele , Zaetta Vania , Follo Marta Dal , Biasion Tiziano , Pessina Achille C.
Published: June 2004

Little is known about the clinical significance of isolated ambulatory hypertension, a condition characterized by low office but elevated ambulatory blood pressure. This study aimed to investigate the prevalence and the predictive value of isolated ambulatory hypertension diagnosed after 3 months of observation for the development of sustained hypertension within a cohort of 871 never-treated stage-1 hypertensive subjects. The study end point was progression to more severe hypertension and need of antihypertensive medication. In 244 subjects (28%), clinic blood pressure declined to <140/90 mm Hg after 3 months. Of these, 124 (14.2% of total) had low clinic and ambulatory blood pressures after 3 months (nonhypertensive subjects), whereas 120 subjects (13.8% of total) showed low clinic but elevated ambulatory blood pressure (isolated ambulatory hypertension). During the 6 years of observation, the number of end points based on multiple clinic blood pressure readings progressively increased from the nonhypertensive subjects (19%) to the subjects with isolated ambulatory hypertension (35%) and to the subjects with high clinic and high ambulatory blood pressures (65%,
P
<0.0001). In an adjusted proportional hazard model, isolated ambulatory hypertension status was associated with a 2.2 (
P
=0.02) increase in the risk of reaching the end point in comparison with the nonhypertensive subjects. Final ambulatory systolic blood pressure was also higher in the former than the latter (
P
=0.03). Our results indicate that among subjects screened for stage 1 hypertension, individuals with isolated ambulatory hypertension after 3 months of observation have increased risk of developing sustained hypertension in later life compared with subjects in whom both clinic and ambulatory blood pressures are normal.
Gold Mining in Arabia and the Rise of the Islamic State
Authors: Heck Gene
Published: June 2004

The financial and economic strengths of the early Islamic state have been a source of ongoing speculation, causing some scholars to even question medieval Makkah's economic reason to exist. This article explores the role of precious metals - gold and silver - in lending vitality to the economy of Western Arabia in the formative years of the Dar al-Islam . Combining primary source evidence with artifacts and qualitative and quantitative analysis of mining residuals, including carbon 14 dating, it produces evidence suggesting that such metals played a far more significant role in contemporary commerce and industry than has been heretofore generally acknowledged.
Inter-population variability in Pratylenchus vulnus Allen & Jensen, 1951 (Nematoda: Tylenchida)
Authors: Lax Paola , Doucet Marcelo , Di Rienzo Julio , Pinochet Jorge , Baujard Pierre
Published: June 2004

Data on morphometric characters of females and males belonging to a set of
Pratylenchus vulnus populations and isolates of different geographical
origin and cultured under different developmental conditions were analysed.
Characters were grouped into three categories (low, medium and high
variability) according to a percentage of inter-population variance. The
characters included in the low variability category were barely influenced
by environmental conditions, whereas those characters with high values were
substantially influenced. Some characters are more significant than others
for species identification whereas other, more variable, characters would be
better considered when comparing isolates and/or populations of P. vulnus
.
Identification and genetic diversity of Meloidogyne spp. (Tylenchida: Meloidogynidae) on coffee from Brazil, Central America and Hawaii
Authors: Carneiro Regina , Tigano Myrian , Randig Onivaldo , Almeida Maria Ritta , Sarah Jean-Louis
Published: June 2004

The present study was based on 18 populations of Meloidogyne spp. originating
from different coffee fields in Brazil, Central America and the USA
(Hawaii). The identification of the main species and an outline of the
diversity of root-knot nematodes parasitising coffee in these countries with
respect to esterase phenotypes, morphology and molecular polymorphism, are
provided. With the present electrophoretic procedure, esterase phenotypes
were demonstrated to be species-specific and constitute a good tool for
identifying root-knot species from coffee, viz., M. incognita (Est I1, I2),
M. paranaensis (Est P1, P2), M. arenaria (Est A2), M. arabicida (Est AR2),
M. exigua (Est E1), M. mayaguensis (Est M2) and two unknown populations that
probably represent new species (Est SA2, SA4). The perineal pattern is often
an unreliable character when used alone for making diagnostic conclusions
but, when used as a complementary tool together with enzyme
characterisation, is essential for checking the morphological consistency of
the identification. Male characters are important for confirming the
diagnosis of some species, such as M. paranaensis, M. konaensis and M.
incognita. The results showed that the RAPD markers produced are consistent
with other approaches (esterase phenotypes and morphological features) for
confirming species identification and for estimating genetic relationships
among species and isolates. Phylogenetic analyses showed that M. mayaguensis
and M. exigua are more closely related to one another than they are to the
other species. This was also true for M. javanica, M. arenaria and
Meloidogyne spp. Low levels of intraspecific polymorphism were detected in
M. exigua (8.6%), M. incognita (11.2%) and M. paranaensis (20.3%).
Conversely, M. arenaria and the two unknown Meloidogyne spp. exhibited
higher levels of intra- or interspecific variability (34.9 and 29.9%,
respectively).
A simple method for discriminating Bursaphelenchus xylophilus and B. mucronatus by species-specific polymerase chain reaction primer pairs
Authors: Matsunaga Koji , Togashi Katsumi
Published: June 2004

Two species-specific PCR primer pairs were developed for identifying the two
nematode species, Bursaphelenchus xylophilus and B. mucronatus. The primer
pairs were developed from the sequence of ribosomal DNA (rDNA) repeats to
produce DNA fragments of different lengths by PCR amplification. The DNA
fragments for B. mucronatus and B. xylophilus were 210 bp and 557 bp,
respectively. When mixed, neither primer pair inhibited the PCR
amplification of the other. Five isolates of B. xylophilus and four isolates
of B. mucronatus showed different band profiles of PCR products between the
two species, but identical profiles among isolates of the same species.
Interspecific variation in the site of Tobravirus particle retention in selected virus-vector Paratrichodorus and Trichodorus species (Nematoda: Diptherophorina)
Authors: Karanastasi Eirini , Brown Derek
Published: June 2004

Different combinations of strains of pea early-browning and tobacco rattle Tobraviruses with selected Paratrichodorus and Trichodorus species were examined to identify if differences occurred in the location of virus particle retention within the nematodes. The study revealed that the sites of virus particle retention differed between the individual Tobravirus-trichodorid combinations. No differences were found in the sites of virus retention in nematodes that had been allowed to acquire, but not to transmit, virus compared with nematodes that had been allowed to acquire and subsequently transmit the virus. Virus particles of several strains of Tobraviruses were acquired and retained by trichodorids that are not natural vectors of the particular virus. In these instances the particles were retained within the pharyngeal tract at locations from where when released they are unable to be transferred anteriorly along the pharyngeal tract into plant cells, but rather they can move only posteriorly into the nematode intestine.
The Fisheries Issues of the 2004 Second European Union Accession Treaty: A Comparison with the 1994 First Accession Treaty
Authors: Ørebech Peter
Published: June 2004

The 1994 and 2004 Accession Treaty and Act of Accession require that the Applicant Member States adopt EU legislation and policy. The goal of the Accession Treaty is to phase out Applicant Member State legislation and institute the pre-emptive role of EU law. The EU fisheries acquis directly affects natural and juridical persons. Member states maintain legislative competence within 12 nautical miles during the transitional period, which ends in 2012. With the exception of specific areas delegated to Member States, national provisions will then be terminated. The "relative stability" and national quota regulations remain in effect and deter direct fishing by other Member States' vessels. Quota hopping, on the other hand, opens the door to foreign fishing interests. A new system of individual transferable quotas will further contribute to the decline of the inherent discrimination amongst EU citizens within fisheries sector.
The Swordfish Dispute between the EU and Chile at the ITLOS and the WTO
Authors:   Orellana
Published: June 2004

During the 1990s and beyond, the European Union (EU) and Chile have been engaged in a controversy over highly migratory swordfish stocks in the South Pacific. Following disputes over Cod, Turbot, and Tuna, the Swordfish Case reveals outstanding problems in the international law of fisheries. The Swordfish Case attracts further attention, as it involves proceedings both at the International Tribunal for the Law of the Sea and at the World Trade Organisation, with potentially inconsistent decisions. At the WTO, the EU's assertion of a right to access Chilean ports on the grounds of GATT 1994 freedom of transit provisions bears an impact on the use of ports in countries around the world. At the ITLOS Chamber, the long-standing conflict between distant water fishing nations and coastal states is once again to the fore. Although the parties to the dispute arrived at a provisional agreement, setting out to establish a scientific fisheries program and a conservation framework, the issues involved in the swordfish controversy highlight the tensions among the international maritime, economic, and environmental regimes. The article offers an overall account of the core elements of the swordfish dispute.
The Work of the International Law Commission at Its Fifty-Third Session (2001)
Authors:   Simma
Published: June 2004

No Abstract