bluuebunny/crossref_metadata_2025 huggingface dataset:
Susceptibility of bovine osteopontin to chymosin
Authors: Kumura Haruto , Miura Atsushi , Sato Eriko , Tanaka Tetsuya , Shimazaki Kei-ichi
Published: November 2004

Osteopontin (OPN) is an acidic phosphorylated glycoprotein found in many tissues and physiological fluids. Bovine OPN is a mature protein comprising 262 amino acids with a calculated molecular weight of 29 kDa. However, SDS-PAGE analysis reveals that the protein isolated from milk migrates to a molecular mass of 60 kDa (Sørensen & Petersen, 1993; Bayless et al. 1997). Bovine milk OPN is phosphorylated at 27 serine residues and one threonine residue (Sorensen et al. 1995); three O-glycosylated threonines were also identified, but no asparagine residues were glycosylated in spite of the presence of three putative N-glycosylation sites. In contrast, eight phosphates are recognized in bovine bone OPN (Salih et al. 1996), and 12 phosphoserines and one phosphothreonine are proposed in addition to five O-linked oligosaccharides and at most one N-linked oligosaccharide in the case of rat bone OPN (Prince et al. 1987). Thus, the possibility of tissue or species-specific differences in post-translational modification has been discussed.
Genotypic and technological characterization of enterococci isolated from artisanal Fiore Sardo cheese
Authors: Cosentino Sofia , Pisano M Barbara , Corda Arianna , Fadda M Elisabetta , Piras Carla
Published: November 2004

A total of 118 enterococcal strains isolated from artisanal Fiore Sardo cheese were characterized technologically and genetically. The presence of potential virulence factors was also investigated. Strains were classified as Ec. faecium (84 strains), Ec. durans (24 strains) and Ec. faecalis (10 strains). RAPD-PCR analysis with two different primers (M13 and XD9) confirmed species identification and proved useful for the detection of interstrain variations, especially among Ec. faecium isolates. Most strains could hydrolyse casein and had weak acidifying activity in milk. None of the isolates produced lipolytic reactions. Gelatinase activity was observed in two strains of Ec. faecalis and one strain of Ec. durans. β-Haemolysis on horses' blood was never detected in any of the strains, independently of species. Most strains produced tyramine from tyrosine but none decarboxylated lysine, histidine or ornithine. Overall, a wide spectrum of resistance was observed. Almost all strains were resistant to the aminoglycosides, gentamycin, kanamycin, streptomycin, neomycin, and to the semisynthetic penicillin, oxacillin, but resistance to vancomycin was not widespread among our strains: only one Ec. faecium and one Ec. durans strain were found to be vancomycin resistant. Our results show a certain diversity in technological traits of the enterococcal strains isolated from artisanal Fiore Sardo, together with a low incidence of some potentially pathogenic traits of health concern.
High pressure-induced denaturation of α-lactalbumin and β-lactoglobulin in bovine milk and whey: a possible mechanism
Authors: Huppertz Thom , Fox Patrick F , Kelly Alan L
Published: November 2004

In this study, high pressure (HP)-induced denaturation of α-lactalbumin (α-la) and β-lactoglobulin (β-lg) in dairy systems was examined. In both milk and whey, β-lg was less baroresistant than α-la; both proteins were considerably more resistant to HP-induced denaturation in whey than in milk. HP-induced denaturation of α-la and β-lg increased with increasing proportion of milk in mixtures of milk and whey. Addition of a sulphydryl-oxidising agent, KIO3, to milk or whey increased HP-induced denaturation of β-lg, but reduced the denaturation of α-la. Denaturation of both α-la and β-lg was prevented by adding a sulphydryl-blocking agent, N-ethylmaleimide, to milk or whey prior to HP treatment, highlighting the crucial role of sulphydryl-disulphide interchange reactions in HP-induced denaturation of α-la and β-lg. Removal of colloidal calcium phosphate from milk also reduced HP-induced denaturation of α-la and β-lg significantly. The higher level of HP-induced denaturation of α-la and β-lg in milk than in whey may be the result of the abscence of the casein micelles and colloidal calcium phosphate from whey, which facilitate HP-induced denaturation of α-la and β-lg in milk.
Autonomous motion of a mobile manipulator using a combined torque and velocity control
Authors: Omrčen Damir , Žlajpah Leon , Nemec Bojan
Published: November 2004

The paper presents an algorithm for real-time motion control of a mobile manipulator in unstructured environments. The mobile manipulator consists of a velocity controlled mobile platform and a torque controlled manipulator. Therefore, a combination of torque and velocity control is used. For the obstacle avoidance two different principles are used: virtual repulsive velocity and action-reaction principle. The proposed control method has been verified on real system, composed of a mobile platform and a four DOFs manipulator arms. The results have been compared to the manipulator with a fixed base.
Reconfigurable distributed real-time processing for multi-robot control: Design, implementation and experimentation
Authors: Pan J. Z. , Patel R. V.
Published: November 2004

Sophisticated robotic applications require systems to be reconfigurable at the system level. Aiming at this requirement, this paper presents the design and implementation of a software architecture for a reconfigurable real-time multi-processing system for multi-robot control. The system is partitioned into loosely coupled function units and the data modules manipulated by the function units. Modularized and unified structures of the sub-controllers and controller processes are designed and constructed. All the controller processes run autonomously and intra-sub-controller information exchange is realized by shared data modules that serve as a data repository in the sub-controller. The dynamic data-management processes are responsible for data exchange among sub-controllers and across the computer network. Among sub-controllers there is no explicit temporal synchronization and the data dependencies are maintained by using datum-based synchronization. The hardware driver is constructed as a two-layered system to facilitate adaptation to various robotic hardware systems. A series of effective schemes for software fault detection, fault anticipation and fault termination are accomplished to improve run-time safety. The system is implemented cost-effectively on a QNX real-time operating system (RTOS) based system with a complete PC architecture, and experimentally validated successfully on an experimental dual-arm test-bed. The results indicate that the architectural design and implementation are well suited for advanced application tasks.
The roles of study-abroad experience and working-memory capacity in the types of errors made during translation
Authors: TOKOWICZ NATASHA , MICHAEL ERICA B. , KROLL JUDITH F.
Published: November 2004

We examined the effects of study-abroad experience (SAE) and working-memory capacity (WMC) on the types of errors made during single-word translation from the first language to the second language, contrasting non-response with meaning errors (i.e. when individuals translate semantically-related words instead of the target word). SAE and WMC interacted; individuals with more SAE and higher WMC made as many meaning as non-response errors, whereas individuals in the other groups made more non-response than meaning errors. We conclude that SAE encourages the use of approximate translations to communicate, but only higher WMC learners can do so because this strategy requires multiple items to be maintained in memory simultaneously. A speech-production model is adapted to capture our results and demonstrate the effects of differential working memory demands on producing correct translations, meaning errors, and non-response errors.
Meteor radar response function: Application to the interpretation of meteor backscatter at medium frequency
Authors: Cervera M. A. , Holdsworth D. A. , Reid I. M. , Tsutsumi M.
Published: November 2004

Recently, Cervera and Elford (2004) extended earlier work on the development of the meteor radar response function (Elford, 1964; Thomas et al., 1988) to include a nonuniform meteor ionization profile. This approach has the advantage that the height distribution of meteors expected to be observed by a radar meteor system is able to be accurately modeled and insights into the meteoroid chemistry to be gained. The meteor radar response function is also an important tool with regard to the interpretation of meteor backscatter in other areas, e.g., modeling the expected diurnal variation of sporadic meteors, investigating the expected echo distribution over the sky, and the calculation of the expected rate curves of meteor showers. We exemplify each of these techniques from the analysis of meteor data collected by the Buckland Park 2 MHz system during October 1997. In addition, we show that the response function may be used to quantify the echo rate of a given shower relative to the sporadic background and thus determine if that shower is able to be detected by the radar.
Height‐resolved ionospheric drifts at low latitudes from simultaneous OI 777.4 nm and OI 630.0 nm imaging observations
Authors: Abalde J. R. , Fagundes P. R. , Sahai Y. , Pillat V. G. , Pimenta A. A. , Bittencourt J. A.
Published: November 2004

Transequatorial F region plasma bubbles are large‐scale ionospheric depleted regions that develop in the bottomside of equatorial F region due to plasma instability processes. Simultaneous all‐sky imaging observations of the OI 630.0 nm and OI 777.4 nm nightglow emissions were carried out at São José dos Campos (23.21°S, 45.86°W; dip latitude 17.6°S), Brazil, during the years 2000 and 2001, a period of high solar activity. In this work we present and discuss the height‐resolved nocturnal F region zonal drift velocities obtained from plasma bubbles observed in imaging observations of these two emissions for several days of 2000 and 2001. It should be pointed out that the two emissions result from different excitation mechanisms (OI 630.0 nm by dissociative recombination of O2+ and OI 777.4 nm by radiative recombination of O+) and come from different F region heights, separated by ∼50–80 km. We have investigated the nighttime zonal plasma drift variations using fixed emission peak altitudes, used by earlier investigators, as well as emission peak altitudes based on simultaneous ionospheric sounding observations. The average maximum and minimum zonal plasma drift velocities inferred for both the emissions, using emission peak altitudes based on simultaneous ionospheric observations, (OI 630.0 nm: 172 ± 2 and 89 ± 15 m/s; OI 777.4 nm: 184 ± 12 and 103 ± 16 m/s) are lower and with less scatter than those using fixed emission peak altitudes (OI 630.0 nm: 185 ± 10 and 104 ± 18 m/s; OI 777.4 nm: 202 ± 19 and 121 ± 20 m/s). Also, the nocturnal variations of the zonal plasma drift velocities obtained for the two emissions with peak altitudes based on simultaneous ionospheric observations show better agreement than for the case with fixed emission peak altitudes (h = 380 km for OI 777.4 nm and h = 300 km for OI 630.0 nm).
Radar interferometry for measuring tidal strains across cracks on Europa
Authors: Sandwell David , Rosen Paul , Moore William , Gurrola Eric
Published: November 2004

A major uncertainty in understanding the interaction between the surface of Europa and its ocean below is the present‐day activity of fractures. Using well‐constrained models for tidal strain and a force balance in a cracked shell, we estimate the shear and normal displacement of cracks that penetrate upward from the base of the shell. If more than half of the plate is fractured, then surface displacements having amplitudes of 3 to 30 cm will be localized in a band 1 to 100 km from the crack. Plate spreading will occur if more than ∼85% of the plate is fractured. The pattern of deformation is sensitive to both the percentage of plate that is cracked and the total thickness of the shell. Repeat‐pass radar interferometry could easily detect and map the activity of the cracks during a short experiment from a variety of suitable orbits with repeating ground tracks.
Final stages of the Variscan orogeny at the southern Iberian massif: Lateral extrusion and rotation of continental blocks
Authors: García‐Navarro Encarnación , Fernández Carlos
Published: November 2004

The southern part of the Iberian Massif contains one of the sutures of the European Variscan belt. Several systems of faults and dikes appear as a result of a period of brittle deformation during the late stages of the Variscan tectonic evolution of this zone. A detailed analysis of these structures has been carried out in this work. Four successive deformation phases have been identified: a first strike‐slip normal faulting stage, a transcurrent stage, a second strike‐slip normal faulting stage, and, finally, a thrusting stage. The age of these phases vary between around 310 Ma and less than 270 Ma. The computed trajectories of the deformation axes show a progressive anticlockwise rotation of around 90°. These data, together with the results of previous geological and geophysical studies of this zone and of the Variscan belt as a whole, lead us to propose a model of tectonic evolution for the last stages of the Variscan collision. Comparison with modern examples of collisional belts and with the results of analog experiments suggests that a promontory of the continental lithosphere of the downgoing plate indented against the active continental margin of the upper plate. The indenter suffered an intense deformation, in accordance with the predictions of some recent analog models simulating the indentation of a four‐layer continental lithosphere. The Variscan and Late Variscan brittle deformation episodes represent the waning stages of the Variscan collision, and not an independent tectonic event.
Dupuit‐Forchheimer solutions for radial flow with linearly varying hydraulic conductivity or thickness of aquifer
Authors: Kitterød Nils‐Otto
Published: November 2004

This paper presents new analytical solutions for steady state piezometric heads in phreatic and confined aquifers with radial flow. The new solutions utilize two constant head boundaries and a hydraulic conductivity k or thickness of aquifer H that is a linear function of radius r. Previous solutions applied constant k and H, and they were usually based on one constant head boundary, which might be superimposed on a solution that allowed a constant discharge or recharge at the center of the aquifer. The previous solutions may be difficult to apply to real aquifers because constant k and H is usually an oversimplification of nature. The Dupuit‐Forchheimer assumption implies that vertical head gradients are ignored. The magnitude of the error introduced by allowing H = H(r) is evaluated numerically in this paper.
Impact of cyclosporine 2‐h level and mycophenolate mofetil dose on clinical outcomes inde novoheart transplant patients receiving anti‐thymocyte globulin induction
Authors: Cantarovich Marcelo , Giannetti Nadia , Cecere Renzo
Published: November 2004

Abstract: Background:Cyclosporine (CsA) 2‐h post‐dose level (C2) correlates better than trough levels (C0) with the area under the curve. We evaluated the clinical impact of C2and mycophenolate mofetil (MMF) dose in adult heart transplant patients receiving anti‐thymocyte globulin (ATG) induction.

Methods:Two immunosuppressive strategies were sequentially evaluated. In Group 1 (13 patients), simultaneous C0/C2(ng/mL) were analyzed. CsA dose monitoring was initially based on C0: <3 months: 200–300, 4–6 months: 150–250, 6–9 months: 100–200, and on C2thereafter (as in Group 2). In Group 2 (nine patients), C2monitoring was implemented: <3 months: 600–800, 4–6 months: 500–700, >6 months: 400–600. All patients received ATG induction, corticosteroids, and MMF (1.0 g b.i.d. in Group 1 and 1.5 g b.i.d. in Group 2).

Results:Patients in Group 2 received higher MMF doses during the first trimester. C2at 1, 3, 6, 12, 24, and 36 months was, respectively, 1199 ± 476, 1202 ± 587, 999 ± 467, 664 ± 203, 593 ± 208, and 561 ± 147 in Group 1, and 809 ± 160 (p = 0.02), 644 ± 178 (p = 0.003), 664 ± 169 (p = 0.02), 616 ± 221, 464 ± 234, and 451 ± 165 in Group 2. The incidence of acute rejection (grade ≥3A) at 6, 12, 24, and 36 months was, respectively, 38.5, 38.5, 46, and 54% in Group 1, and 11, 44, 56, and 56% in Group 2 (p = NS). At 3 months, the creatinine clearance was 25% lower in Group 1. Thereafter, renal function remained stable in both groups.

Conclusion:Our results suggest that heart transplant patients receiving ATG induction may experience similar outcomes with either a higher C2and a lower MMF dose or a lower C2and a higher MMF dose. These results could be considered to design prospective studies to optimize C2monitoring, to reduce the incidence of acute rejection without increasing the risk of renal dysfunction.
Pre‐transplant Th1 and post‐transplant Th2 cytokine patterns are associated with early acute rejection in renal transplant recipients
Authors: Sadeghi M , Daniel V , Weimer R , Wiesel M , Hergesell O , Opelz G
Published: November 2004

Abstract: In this retrospective study, we tried to define pre‐ and post‐transplant immunological parameters that identify patients at risk for early acute rejection. Lymphocyte subpopulations and plasma levels of cytokines and neopterin were determined pre‐ and post‐transplant in 32 renal transplant recipients with biopsy‐proven early acute graft rejection. Recipients without early acute rejection served as controls. High pre‐transplant interferon‐γ (IFN‐γ) plasma levels (p = 0.006), consistently high levels of neopterin early post‐transplant (p = 0.008), a post‐transplant switch from a Th1 to a Th2 cytokine pattern with decreasing IFN‐γ (p = 0.02), low CD8+ lymphocyte counts (p = 0.006) and consistently high CD19+ B lymphocyte counts were associated with acute rejection. Our data suggest that patients with a pre‐transplant Th1 and an early post‐transplant Th2 cytokine pattern are pre‐disposed for early acute rejection.
A neutropenia suggesting an interaction between valacyclovir and mycophenolate mofetil
Authors: Royer Bernard , Zanetta Gilbert , Bérard Michel , Davani Siamak , Tanter Yves , Rifle Gérard , Kantelip Jean‐Pierre
Published: November 2004

Mycophenolate mofetil (MMF) is a drug which decreases the frequency of renal transplantation rejection. However, cytomegalovirus infections are a common feature of this treatment leading the physicians to prescribe antiviral prophylactic drugs like valacyclovir. During this association, neutropenia occur and the cause of this adverse effect is difficult to define. This report presents a case of neutropenia in a woman treated with MMF and valacyclovir. As the duration of the valacyclovir treatment exactly corresponds to the neutropenia duration, and the mycophenolate trough levels increased with the neutrophil count, the responsibility of this neutropenia was ascribed to valacyclovir. However, an examination of the literature for cases of neutropenia led to the suspicion of an interaction between MMF and valacyclovir. Mycophenolate may increase intracellular concentrations of valacyclovir up to haematotoxic levels. This mechanism may explain the interaction and further research is needed to confirm this interaction.
Detection of simultaneous β‐herpesvirus infections in clinical syndromes due to defined cytomegalovirus infection
Authors: Razonable Raymund R , Rivero Antonio , Brown Robert A , Hart Gregory D , Espy Mark J , Van Cruijsen Hester , Wilson Jennie , Groettum Cynthia , Kremers Walter , Smith Thomas F , Paya Carlos V
Published: November 2004

Abstract: Human herpesvirus (HHV)‐6 and HHV‐7 are increasingly being recognized as emerging pathogens among transplant recipients. Using quantitative polymerase chain reaction assays, we demonstrate the presence of HHV‐6 and/or HHV‐7 in 18 of 20 episodes of clinically presumed or microbiologically confirmed cytomegalovirus (CMV) infection. Seventeen (89%) of 19 microbiologically confirmed cytomegalovirus (CMV)‐infected patients had concomitant HHV‐6 variant B (47%) and/or HHV‐7 (63%) infection. The degree of HHV‐6 coinfection was significantly correlated with hyperbilirubinemia while HHV‐7 coinfection demonstrated a non‐significant trend toward cytopenias. In one of the 20 episodes described herein, the ‘viral syndrome’ was due solely to HHV‐7 infection; clinical and virological response was observed during intravenous ganciclovir therapy in this patient. While this study emphasizes the significance of HHV‐6 and/or HHV‐7 coinfection during episodes of CMV infection, it significantly highlights the novel observation of the causal role of HHV‐7 (in the absence of HHV‐6 and CMV) in a clinical illness presumed to be caused CMV. Thus, HHV‐7 (and HHV‐6) should be considered as a pathogen (or copathogen) in the viral syndromes following organ transplantation.
Genomic structure of mouse PIR‐A6, an activating member of the paired immunoglobulin‐like receptor gene family
Authors: Tun T. , Kubagawa Y. , Dennis G. , Burrows P.D. , Cooper M.D. , Kubagawa H.
Published: November 2004

Abstract:  The gene for one of the activating members of the paired Ig‐like receptor family, Pira6, was isolated from a genomic library and sequenced. The first of 9 exons in the ∼8.2 kb Pira6 gene encodes the 5′ untranslated region, the translation initiation site, and approximately half of the signal sequence. The second exon encodes the rest of the signal sequence, exons 3–8 each encode a single Ig‐like extracellular domain, and exon 9 encodes the transmembrane region, cytoplasmic tail and 3′ UTR with four polyadenylation signals and six mRNA instability sequences. A soluble form of PIR‐A6 may be generated by alternative splicing. The exonic sequences account for ∼42% of the Pira6 gene and ∼34% for the single inhibitory Pirb gene, thus defining Pira and Pirb as genes with relatively short intronic sequences. Extensive sequence homology was found between Pira6 and Pirb from ∼2 kb upstream of the ATG initiation site to the beginning of intron 8. The Pir genes appear to be distributed in three regions of the proximal end of chromosome 7 based on the present data and an analysis of currently available mouse genomic sequence databases. One region contains a single Pir gene which is almost identical to Pira6, and the other two contain multiple Pir genes in opposite transcriptional orientations. Potential binding sites for hemopoiesis‐specific and ubiquitous transcription factors were identified upstream of the Pira6 transcription start sites that reside within the initiator consensus sequence motif. These results provide important clues to the coordinate regulation observed for PIR‐A and PIR‐B expression during hematopoiesis.
Antibacterial activities and conformations of synthetic α‐defensin HNP‐1 and analogs with one, two and three disulfide bridges
Authors: Mandal M. , Nagaraj R.
Published: November 2004

Abstract:Structure and biological activities of synthetic peptides corresponding to human α‐defensin HNP‐1, AC1YC2RIPAC3IAGERRYGTC4IYQGRLWAFC5C6with the S–S connectivities: C1–C6, C2–C4, C3–C5, and its variants with one, two and three disulfide bridges were investigated. Oxidation of synthetic, reduced HNP‐1 yielded a peptide with S–S connectivities C1–C3, C2–C4and C5–C6, and not with the S–S linkages as in naturally occurring HNP‐1. Selective protection of cysteine sulfhydryls was necessary for the formation of S–S bridges as in native HNP‐1. Likewise, oxidation of peptide encompassing the segment from C2to C5, resulted in the S–S linkages C2–C3and C4–C5instead of the expected linkage C2–C4and C3–C5. Antibacterial activities were observed for all peptides, irrespective of how the S–S bridges were linked. Linear peptides without S–S bridges were inactive. Circular dichroism (CD) spectra suggest that peptides constrained by one and two S–S bridges do not form rigid β‐sheet structures in an aqueous environment. The spectrum of HNP‐1 in an aqueous environment suggests the presence of a β‐hairpin conformation. In the presence of lipid vesicles, the S–S constrained peptides tend to adopt a β‐structure. Although the S–S connectivities observed in HNP‐1 may be necessary for other physiological activities, such as chemotaxis, they are clearly not essential for antibacterial activity.
Crystal structure of biphalin sulfate: a multireceptor opioid peptide
Authors: Flippen‐Anderson J.L. , Deschamps J.R. , George C. , Hruby V.J. , Misicka A. , Lipkowski A.W.
Published: November 2004

Abstract: Biphalin is a dimeric opioid peptide, composed of two tetrapeptides connected ‘tail‐to‐tail’, that exhibits a high affinity for all three opioid receptor types (i.e. µ, δ and κ). This study presents the X‐ray crystal structure of biphalin sulfate and compares it to other opioids that interact with the same biological targets. Both halves of the molecule have a folded backbone conformation but differ significantly from one another. Residues 1–4 in biphalin, which compare well with the δ selective opioid peptide DADLE, fold into a random coil. Residues 5–8, which can be fit to the µ selective peptide d‐TIPP‐NH2, exhibit a fairly normal type III′β bend. Biphalin also exhibits structural similarities with two naltrexone analogs, naltrexonazine and norbinaltorphamine, that are specific to µ and κ receptor sites.
Dysplasia of tubular cells in a kidney‐ transplanted patient treated with recombinant human growth hormone
Authors: Herman Jean , Van Damme Bo , Van Damme‐Lombaerts Rita
Published: November 2004

Abstract: After renal transplantation (Tx), children with growth retardation can be successfully treated with recombinant human growth hormone (rhGH). However, the impact of this treatment on kidney allograft function remains a source of concern. We report on one boy who received a cadaveric kidney transplant at 12 yr of age, after developing end‐stage focal and segmental glomerulosclerosis and hyalinosis. The early post‐transplant period was complicated by thrombosis of an arterial branch of the graft and two acute rejection episodes. Because of poor growth, the boy was treated with rhGH starting 22 months after the Tx. The renal function remained relatively stable for 22 months after initiation of rhGH therapy and then progressively deteriorated over a period of 10 months, with the patient ending up on dialysis. Several biopsies, performed for rejection episodes or before the start of rhGH, or to elucidate the deterioration of the renal function, were analyzed. Histologically, a progressive increase in the amount of hypertrophy of the tubules and of the glomeruli was seen after initiation of rhGH. Hyperplasia of the tubular epithelium with crowding of cells of the proximal tubules, hyperchromasia and irregularities in the shape of the nuclei, and abrupt changes of chromatism along the tubuli, were also observed. These lesions of tubular dysplasia are extremely unusual in transplanted kidneys and are unlikely to be caused by compensatory hypertrophy secondary to destruction of renal tissue. They may be an effect of rhGH treatment. The prognostic significance of these lesions is unknown but merits attention.
High trough levels of oral FK506 induced by loss of small intestine
Authors: Sano Nobuyuki , Nio Masaki , Shimaoka Satoru , Ishii Tomohiro , Amae Shintaro , Wada Motoshi , Ohi Ryoji
Published: November 2004

Abstract: To establish a safe and effective usage of oral tacrolimus (FK506) in small bowel transplantation (SBTx) recipients, trough levels and area under the curve (AUC) values of FK506 were assessed using swine models of SBTx and short bowel. Thirty‐eight Landrace male piglets were divided into four groups as follows: Group 1, controls (n=13); Group 2, a one‐third small bowel model (n=5); Group 3, a short bowel model (n=10); and Group 4, a one‐third small bowel allograft model (n=10; five donors and five recipients). Piglets of Groups 1 and 3 were further divided into two sub‐groups, according to the route of drug administration: Groups 1a (n=10) and 3a (n=7) received FK506 orally, and Groups 1b (n=3) and 3b (n=3) received FK506 intravenously. Oral or intravenous FK506 was started on post‐operative day 3 and continued until day 7 in each group. On day 7, trough levels and AUC values were measured. In Groups 1a, 2, 3a and 4, trough levels of FK506 were 2.1±1.2 (p<0.01 vs. Group 2, 3a or 4), 11.2±2.1, 23.3±4.8 (p<0.05 vs. Group 2 or 4) and 14.6±3.0 ng/mL, and AUC values were 101±90 (p<0.01 vs. Group 3a or 4), 319&±155, 808±200, and 531±113 ng.h/mL, respectively. Both trough levels and AUC values were lowest in Group 1a and highest in Group 3a. Between Groups 1b and 3b, there was no significant difference in the blood levels of intravenous FK506. The shorter the functioning residual small intestine was, the higher the trough level of oral FK506 was, while the presence or absence of small intestine did not affect blood levels of intravenous FK506. These results suggest that oral FK506 is metabolized in the functioning small intestine during its absorption. Therefore, events which cause intestinal malfunction, such as graft rejection in SBTx, inflammation and loss of small intestine, may adversely raise the trough level of oral FK506.
Targeting gene expression to endothelium in transgenic animals: a comparison of the human ICAM‐2, PECAM‐1 and endoglin promoters
Authors: Cowan Peter J. , Shinkel Trixie A. , Fisicaro Nella , Godwin James W. , Bernabéu Carmelo , Almendro Nuria , Rius Carlos , Lonie Andrew J. , Nottle Mark B. , Wigley Peter L. , Paizis Kathy , Pearse Martin J. , D'apice Anthony J. F.
Published: November 2004

Abstract: It is highly likely that successful pig‐to‐human xenotransplantation of vascularized organs will require genetic modification of the donor pig, and in particular of donor vascular endothelium. Promoters are generally tested in transgenic mice before generating transgenic pigs. Several promoters have been used to drive endothelial cell‐specific expression in mice but none have yet been tested in pigs. We compared the promoters of three human genes that are predominantly expressed in vascular endothelium: intercellular adhesion molecule 2 (ICAM‐2), platelet endothelial cell adhesion molecule 1 (PECAM‐1) and endoglin. Expression of human complement regulatory proteins (hCRPs), directed by each of the promoters in mice, was largely restricted to vascular endothelium and leukocyte subpopulations. However, expression from the PECAM‐1 promoter was weak in liver and non‐uniform in the small vessels of heart, kidney, and lung. Conversely, expression from the endoglin promoter was consistently strong in the small vessels of these organs but was absent in larger vessels. The ICAM‐2 promoter, which produced strong and uniform endothelial expression in all organs examined, was therefore used to generate hCRP transgenic pigs. Leukocytes from 57 pigs containing at least one intact transgene were tested for transgene expression by flow cytometry. Forty‐seven of these transgenic pigs were further analyzed by immunohistochemical staining of liver biopsies, and 18 by staining of heart and kidney sections. Only two of the pigs showed expression, which appeared to be restricted to vascular endothelium in heart and kidney but was markedly weaker than in transgenic mice produced with the same batch of DNA. Thus, in this case, promoter performance in mice and pigs was not equivalent. The weak expression driven by the human ICAM‐2 promoter in pigs relative to mice suggests the need for additional regulatory elements to achieve species‐specific gene expression in pigs.
Porcine CD80: cloning, characterization, and evidence for its role in direct human T‐cell activation
Authors: Tadaki D. K. , Williams A. , Lee K. P. , Kirk A. D. , Harlan D. M.
Published: November 2004

Abstract: Previous studies has shown that human anti‐pig reactivity in mixed lymphocyte cultures require the indirect presentation of antigens by human antigen presenting cells (APC). Xenoreactivity was inhibited by blockade of human costimulatory molecules. We investigated the role of porcine costimulatory molecules in their ability to activate human T cells directly. Porcine CD80 was cloned from lipopolysaccharide (LPS)‐activated porcine lymphocytes. Sequence analysis showed a high degree of conservation in residues involved in CD28/CTLA4. COS cells transfected with porcine CD80 was able to activate human T cells in a cyclosporine independent manner, demonstrating that porcine CD80 can costimulate human T cells. Tumor necrosis factor‐α (TNF‐α) activated porcine splenocytes have been shown to up‐regulate B7s. In order to test the effect of costimulation blockade in a xeno system, activated splenocytes were cultured with purified CD4+ T cells. The results demonstrated that these cells were capable of activating human T cells and this activation can be blocked by using an antihuman CD80 antibody that demonstrated cross‐reactivity to porcine CD80. Non‐cross reactive antibodies had no effect, again suggesting direct activation of the human T cells. These data suggest that a reagent that can block both the direct and indirect activation is necessary for a discordant xenotransplant.
Laying order, hatching asynchrony and nestling body mass in Tree Swallows Tachycineta bicolor
Authors: Clotfelter Ethan D. , Whittingham Linda A. , Dunn Peter O.
Published: November 2004

We studied the reproductive biology of a box‐nesting population of Tree Swallows Tachycineta bicolor in southeastern Wisconsin, USA. We were interested particularly in the relationship between laying order and hatching order and the extent to which each was a predictor of nestling body mass. We found that laying order was a significant predictor of hatching order. Laying and hatching order were related to nestling mass at 4 days of age and to a lesser extent at 12 days of age. In addition, we investigated the effects of natural variation in hatching asynchrony. Hatching asynchrony was positively related to the range of nestling body masses within a brood at days 4 and 12. The probability that brood reduction occurred was also positively related to the degree of hatching asynchrony, though this effect was significant only at day 4. Our results suggest that laying order and hatching order have their greatest effects on nestling Tree Swallows early in the nestling period.
The effect of food availability on the foraging behaviour of breeding Great Skuas Catharacta skua and Arctic Skuas Stercorarius parasiticus
Authors: Caldow R. W. G. , Furness R. W.
Published: November 2004

Seabirds’ behavioural activity budgets have been proposed as an indicator of changes in marine food supplies. Reduced recruitment and a low biomass of sandeels Ammodytes spp. around Shetland in the late
1980s were associated with a dramatic increase in the foraging effort of
breeding skuas. We present data on the territorial attendance patterns of
breeding Great Skuas Catharacta skua and Arctic Skuas
Stercorarius parasiticus in Shetland in 1987 and examine three aspects of the recorded increase in foraging effort.

Time budget studies indicate that recording territorial attendance by infrequent, daily spot observations provides an accurate measure of the time spent off‐territory by both skua species. None of the pairs of Arctic Skua studied ever left their chicks unattended in 1987. The same was true of 10 out of 27 pairs of Great Skuas. Although the remaining pairs of Great Skuas frequently left their chicks unprotected, evidence of pair co‐ordination to minimise this suggests that their foraging schedules were still constrained by the need to protect their offspring. During periods of high chick‐demand, variation between pairs’ foraging efforts largely reflected variation in those of the females. Thus, we suggest that increased chick neglect in years of food shortage arises as females abandon their role of guardian for that of provider. By the end of the breeding season in 1987, both male and female Great Skuas foraged from 65 to 89% of daylight hours. The lack of any further increase in the foraging effort of Great Skuas in subsequent years of poorer reproductive success was almost certainly because time and energy constraints prevented either sex from doing so. We suggest that the comparatively short amount of time spent foraging by Arctic Skuas in 1987 may reflect an advantage conferred by their role as specialist kleptoparasites.
Computer‐assisted treatment planning and analysis
Authors: Beers AC , Choi W , Pavlovskaia E
Published: November 2004

Authors– Beers AC, Choi W, Pavlovskaia E

The Invisalign® orthodontic system (Align Technology, Inc, Santa Clara, CA) is a series of clear removable appliances that is worn by a patient to correct malocclusions. Introduced in 1999, it has been applied to successfully correct an increasingly wide variety of malocclusions. Part of the success of the system is because of the innovative technologies inherent in the design of the appliances.

During the development of the system, many challenges and issues needed to be overcome to realize the product. Many of these issues were not specific to Invisalign®, and represented general problems in the area of computer‐aided orthodontics. The general problems of developing a virtual model of a patient's dentition appropriate for use in orthodontics, performing a treatment plan on a virtual dentition model, and analyzing how accurately the virtual treatment plan executed in the patient's mouth are presented.
Current status and future needs in craniofacial imaging
Authors: Mah J , Hatcher D
Published: November 2004

Authors

– Mah J, Hatcher D

Imaging is a keystone in understanding and delivery of craniofacial health care. Recent developments in imaging have brought forth many diverse technologies and approaches. This review provides the current status of methods in craniofacial imaging and discusses future needs and directions. New developments in three‐dimensional dental and skeletal imaging, as well as three‐dimensional facial image acquisition and animation of jaw movement and facial expression are reviewed. Visualization and convergence of the data from these technologies for construction of patient‐specific models is described. Insights on how these technologies and approaches could impact research, education as well as the future of craniofacial health care will be discussed.
Fundamentals of image acquisition and processing in the digital era
Authors: Farman AG
Published: November 2004

Structured Abstract

Author– Farman AG

Objectives – To review the historic context for digital imaging in dentistry and to outline the fundamental issues related to digital imaging modalities.

Context – Digital dental X‐ray images can be achieved by scanning analog film radiographs (secondary capture), with photostimulable phosphors, or using solid‐state detectors (e.g. charge‐coupled device and complementary metal oxide semiconductor). There are four characteristics that are basic to all digital image detectors; namely, size of active area, signal‐to‐noise ratio, contrast resolution and the spatial resolution. To perceive structure in a radiographic image, there needs to be sufficient difference between contrasting densities. This primarily depends on the differences in the attenuation of the X‐ray beam by adjacent tissues. It is also depends on the signal received; therefore, contrast tends to increase with increased exposure. Given adequate signal and sufficient differences in radiodensity, contrast will be sufficient to differentiate between adjacent structures, irrespective of the recording modality and processing used. Where contrast is not sufficient, digital images can sometimes be post‐processed to disclose details that would otherwise go undetected. For example, cephalogram isodensity mapping can improve soft tissue detail.

Conclusions – It is concluded that it could be a further decade or two before three‐dimensional digital imaging systems entirely replace two‐dimensional analog films. Such systems need not only to produce prettier images, but also to provide a demonstrable evidence‐based higher standard of care at a cost that is not economically prohibitive for the practitioner or society, and which allows efficient and effective workflow within the business of dental practice.
Dynamic modeling and jaw biomechanics
Authors: Hannam AG
Published: November 2004

Author– Hannam AG

Bioengineered simulations of dynamic events in the human masticatory system are relatively new. A primary advantage is their ability to integrate structure and function in cause‐and‐effect scenarios. By permitting detailed analyses of these interactions, and the prototyping of prosthetic additions, the models generate working hypotheses. Significant issues in their use include the importation and measurement of structural geometry, the choice of parameters affecting dynamics (e.g. inertial properties and viscoelasticities) and the nature of the modeling process (e.g. whether models are kinetically driven by muscle contraction, or kinematically defined by movement channels). Presently, there are few accepted standards or conventions for managing these computational data in the human jaws, and the data used are often derived from multiple and disparate sources. This review focuses on the approaches, assumptions, and key applications of dynamic modeling in the human masticatory system. It considers the role of imaging, the restrictions imposed by assumptions of unknown or unverifiable data, and how modeling can be a useful research technique despite these hurdles. The review concludes with a comment on creating virtual models for educational purposes.
Computer‐assisted simulations in orthodontic diagnosis and the application of a new cone beam X‐ray computed tomography
Authors: Maki K , Inou N , Takanishi A , Miller AJ
Published: November 2004

Authors– Maki K, Inou N, Takanishi A, Miller AJ

Computational simulations which include three‐dimensional (3‐D) image processing and biomechanical calculations should provide useful information to our research and orthodontic clinic as a clinical tool defined as ‘thinking’. In this review, 1) biomechanical simulations applied to predict the mandibular growth; 2) mathematical models of virtual bone cells and 3) 3‐D images and solid model simulations for surgical planning are introduced.

In biomechanical simulation, biting force, electromyographic (EMG) activity and cephalograms of 32 subjects were applied. Computational results of mathematical model were compared with actual bone growth in a rat. Three‐dimensional image and solid model of 14 patients were utilized for their treatment planning. From the results, several concepts of our simulations were confirmed: 1) reaction forces generated by masticatory muscles at the condyle control the direction of mandibular growth; 2) some mathematical models have the possibility to describe the process of bone growth; 3) 3‐D image processing software and solid models are necessary for diagnosis and planning of orthognathic surgery.

We also believe that the orthodontists can more accurately predict the affects of surgical procedures and orthodontic tooth movement using the new cone beam X‐ray computed tomography (CT) (CB MercuRay™; Hitachi Medico Technology, Tokyo, Japan) and its advanced application software.
Assessing communication skills for medical interviews in a postgraduate clinical training course at Hiroshima University Dental Hospital
Authors: Ogawa Tetsuji , Taguchi Norihiro , Sasahara Hisako
Published: November 2004

The study was conducted to investigate and clarify the effectiveness of our method of teaching communication and interview skills for medical interviews. Subjects were 18 first‐year residents, enrolled in a postgraduate clinical training course at Hiroshima University Dental Hospital. Subjects underwent two objective structured clinical examinations (OSCEs), and the results of instructor and resident assessments of various elements dealing with necessary communication skills for conducting medical interviews were analysed. A statistically significant correlation between assessments of instructors and residents was observed in one element: confirming patient identity and introducing self (r = 0.812, p < 0.001) in the first interview. However, a statistically significant correlation between assessments of instructors and residents was observed in four elements in the second interview: greeting the patient (r = 0.548, p < 0.05), maintaining physical distance (r = 0.582, p < 0.05), showing empathy (r = 0.601, p < 0.05), summarizing and reconfirming patient complaints (r = 0.628, p < 0.01). Total scores given by instructors in the second OSCE were higher than those in the first OSCE (p < 0.001). The correlation coefficients of the total score in the first and second interviews were r = 0.020 and 0.679 (p < 0.01), respectively. These results may suggest the educational effectiveness of OSCE on the acquisition of communication skills for medical interviews. However, the results of resident self‐assessments reveal that OSCE should be performed at least twice in order for residents to acquire the necessary communication skills for medical interviews.
Acceptance of video‐based teaching in paediatric dentistry by undergraduate dental students
Authors: Kalwitzki Matthias , Rosendahl Riitta , Göttle Richard , Weiger Roland
Published: November 2004

Five cohorts of undergraduate students (n = 160) were filmed on video tape while performing paediatric treatments. Sequences of these recordings were shown 1 day later and discussed. Thus, within one term each student was able to view himself as well as fellow students on video. After the completion of the clinical course in paediatric dentistry, students were asked by means of a questionnaire about the acceptance and benefits of video‐based teaching in paediatric dentistry. 95.5% welcomed the use of video in paediatric dentistry. Concerning the benefits gained from the video showing the treatment that had been performed by the student himself, 83.4% said they had gained new insights in their own behaviour and 80.3% thought these insights to be useful for their clinical work. For the video showing treatments by fellow students, numbers were higher: 84.7 and 89.8%, respectively. Gender‐specific differences revealed that women feel more disturbed by the fact that they are being filmed (7.8% vs. 14.9%), some even think that they would have performed a better treatment without the video. Out of four didactical means, video gained the highest vote, followed by seminars, lectures and slides. It is concluded that the use of video is a valuable didactical means that should be considered in teaching undergraduate students.
The acceptability of the use of sedation in the management of dental anxiety in children: views of dental students
Authors: Newton J. T. , Naidu R. , Sturmey P.
Published: November 2004

The aim of the present study was to determine the views of dental students concerning the acceptability of the use of sedation in the management of dentally anxious children. Dental students in Trinidad (n = 100) were asked to rate the acceptability of vignettes describing the management of a young teenager with dental anxiety. The vignettes varied systematically along two dimensions: nature of intervention for anxiety (sedation vs. the use of relaxation training and rewards) and outcome of the intervention (good vs. poor). Ratings of acceptability were made using a standardized questionnaire measure. The data were analysed using analysis of variance (ANOVA). There were significant main effects of nature of intervention (F = 5.54; P < 0.05) and outcome of intervention (F = 298.01; P < 0.001), though the students' year of study did not influence ratings. None of the interaction terms were significant. Sedation was viewed as a less acceptable intervention than relaxation and rewards. Interventions associated with good outcomes were seen as more acceptable than interventions associated with poor outcomes. It is concluded that dental students' perceptions of the acceptability of interventions for use with dentally anxious patients are related to the effectiveness of the intervention. Sedation, regardless of the outcome, is seen as less acceptable than the use of rewards and relaxation.