bluuebunny/crossref_metadata_2025_split huggingface dataset:
The angiogenic factor CCN1 promotes adhesion and migration of circulating CD34+ progenitor cells: potential role in angiogenesis and endothelial regeneration
Authors: Grote Karsten , Salguero Gustavo , Ballmaier Matthias , Dangers Marc , Drexler Helmut , Schieffer Bernhard 
Published: April 2007

Abstract
Tissue regeneration involves the formation of new blood vessels regulated by angiogenic factors. We reported recently that the expression of the angiogenic factor CCN1 is up-regulated under various pathophysiologic conditions within the cardiovascular system. Because CD34+ progenitor cells participate in cardiovascular tissue regeneration, we investigated whether CCN1—detected for the first time in human plasma—promotes the recruitment of CD34+ progenitor cells to endothelial cells, thereby enhancing endothelial proliferation and neovascularization. In this study, we demonstrated that CCN1 and supernatants from CCN1-stimulated human CD34+ progenitor cells promoted proliferation of endothelial cells and angiogenesis in vitro and in vivo. In addition, CCN1 induced migration and transendothelial migration of CD34+ cells and the release of multiple growth factors, chemokines, and matrix metalloproteinase-9 (MMP-9) from these cells. Moreover, the CCN1-specific integrins αMβ2 and αVβ3 are expressed on CD34+ cells and CCN1 stimulated integrin-dependent signaling. Furthermore, integrin antagonists (RGD-peptides) suppressed both binding of CCN1 to CD34+ cells and CCN1-induced adhesion of CD34+ cells to endothelial cells. These data suggest that CCN1 promotes integrin-dependent recruitment of CD34+ progenitor cells to endothelial cells, which may contribute to paracrine effects on angiogenesis and tissue regeneration.
A screening and intervention program aimed to reduce mortality and serious morbidity associated with severe neonatal alloimmune thrombocytopenia
Authors: Kjeldsen-Kragh Jens , Killie Mette Kjær , Tomter Geir , Golebiowska Elzbieta , Randen Ingrid , Hauge Reidun , Aune Berit , Øian Pål , Dahl Lauritz B. , Pirhonen Jouko , Lindeman Rolf , Husby Henrik , Haugen Guttorm , Grønn Morten , Skogen Bjørn , Husebekk Anne 
Published: April 2007

Abstract
The study's objective was to identify HPA 1a–negative women and to offer them an intervention program aimed to reduce morbidity and mortality of neonatal alloimmune thrombocytopenia (NAIT). HPA 1 typing was performed in 100 448 pregnant women. The HPA 1a–negative women were screened for anti–HPA 1a. In immunized women, delivery was performed by Cesarean section 2 to 4 weeks prior to term, with platelets from HPA 1a–negative donors reserved for immediate transfusion if petechiae were present and/or if platelet count was less than 35 × 109/L. Of the women screened, 2.1% were HPA 1a negative, and anti–HPA 1a was detected in 10.6% of these. One hundred seventy pregnancies were managed according to the intervention program, resulting in 161 HPA 1a–positive children. Of these, 55 had severe thrombocytopenia (< 50 × 109/L), including 2 with intracranial hemorrhage (ICH). One woman with a twin pregnancy missed the follow-up and had one stillborn and one severely thrombocytopenic live child. In 15 previous prospective studies (136 814 women) there were 51 cases of severe NAIT (3 intrauterine deaths and 7 with ICH). Acknowledging the limitation of comparing with historic controls, implementation of our screening and intervention program seemed to reduce the number of cases of severe NAIT-related complications from 10 of 51 to 3 of 57.
Hydroxyurea therapy lowers transcranial Doppler flow velocities in children with sickle cell anemia
Authors: Zimmerman Sherri A. , Schultz William H. , Burgett Shelly , Mortier Nicole A. , Ware Russell E. 
Published: April 2007

Abstract
Hydroxyurea has hematologic and clinical efficacy in sickle cell anemia (SCA), but its effects on transcranial Doppler (TCD) flow velocities remain undefined. Fifty-nine children initiating hydroxyurea therapy for clinical severity had pretreatment baseline TCD measurements; 37 with increased flow velocities (≥ 140 cm/s) were then enrolled in an institutional review board (IRB)–approved prospective phase 2 trial with TCD velocities measured at maximum tolerated dose (MTD) and one year later. At hydroxyurea MTD (mean ± 1 SD = 27.9 ± 2.7 mg/kg per day), significant decreases were observed in the right middle cerebral artery (MCA) (166 ± 27 cm/s to 135 ± 27 cm/s, P < .001) and left (MCA) (168 ± 26 cm/s to 142 ± 27 cm/s, P < .001) velocities. The magnitude of TCD velocity decline was significantly correlated with the maximal baseline TCD value. At hydroxyurea MTD, 14 of 15 children with conditional baseline TCD values improved, while 5 of 6 with abnormal TCD velocities whose families refused transfusions became less than 200 cm/s. TCD changes were sustained at follow-up. These prospective data indicate that hydroxyurea can significantly decrease elevated TCD flow velocities, often into the normal range. A multicenter trial is warranted to determine the efficacy of hydroxyurea for the management of increased TCD values, and ultimately for primary stroke prevention in children with SCA.
Iron chelation and regulation of the cell cycle: 2 mechanisms of posttranscriptional regulation of the universal cyclin-dependent kinase inhibitor p21CIP1/WAF1 by iron depletion
Authors: Fu Dong , Richardson Des R. 
Published: April 2007

AbstractIron (Fe) plays a critical role in proliferation, and Fe deficiency results in G1/S arrest and apoptosis. However, the precise role of Fe in cell-cycle control remains unclear. We observed that Fe depletion increased the mRNA of the universal cyclin-dependent kinase inhibitor, p21CIP1/WAF1, while its protein level was not elevated. This observation is unique to the G1/S arrest seen after Fe deprivation, as increased p21CIP1/WAF1 mRNA and protein are usually found when arrest is induced by other stimuli. In this study, we examined the posttranscriptional regulation of p21CIP1/WAF1 after Fe depletion and demonstrated that its down-regulation was due to 2 mechanisms: (1) inhibited translocation of p21CIP1/WAF1 mRNA from the nucleus to cytosolic translational machinery; and (2) induction of ubiquitin-independent proteasomal degradation. Iron chelation significantly (P < .01) decreased p21CIP1/WAF1 protein half-life from 61 (± 4 minutes; n = 3) to 28 (± 9 minutes, n = 3). Proteasomal inhibitors rescued the chelator-mediated decrease in p21CIP1/WAF1 protein, while lysosomotropic agents were not effective. In Fe-replete cells, p21CIP1/WAF1 was degraded in an ubiquitin-dependent manner, while after Fe depletion, ubiquitin-independent proteasomal degradation occurred. These results are important for considering the mechanism of Fe depletion–mediated cell-cycle arrest and apoptosis and the efficacy of chelators as antitumor agents.
β2-Adrenoceptor polymorphisms and asthma phenotypes: interactions with passive smoking
Authors: Zhang G. , Hayden C. M. , Khoo S-K. , Candelaria P. , Laing I. A. , Turner S. , Franklin P. , Stick S. , Landau L. , Goldblatt J. , Le Souëf P. N. 
Published: April 2007

The aim of the present study was to assess the effects of possible interactions between β2-adrenoceptor gene polymorphisms and passive smoking on forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and exhaled nitric oxide (eNO) in children aged 11 yrs.A cross-sectional analysis of the longitudinal cohort was conducted for associations between β2-adrenoceptor gene polymorphisms and lung function and eNO with regard to passive smoking.Among children exposed to tobacco smoke, those with Arg16 (at least one Arg allele) exhibited lower adjusted mean FEV1(2.19versus2.38 L) and FVC (2.43versus2.64 L) than Gly16 homozygotes. Those with Gln27 (at least one Gln allele) also exhibited a lower adjusted mean FEV1relative to Glu27 homozygotes (2.24versus2.39 L). Among children with no exposure to smoking, those with Arg16 or Gln27 showed lower adjusted geometric mean eNO levels compared with Gly16 homozygotes (15.4versus30.9 ppb) and Glu27 homozygotes (18.0versus49.7 ppb).In conclusion, passive smoking had a significant effect on associations between β2-adrenoceptor gene polymorphisms and asthma-related phenotypes, enhancing the relationship between Arg16 and lung function and removing the relationship between Arg16 or Gln27 and exhaled nitric oxide levels.
Stratified exhaust gas recirculation under lean operation of a liquefied petroleum gas spark-ignition engine with liquid phase injection
Authors: Woo Youngmin , Bae Choongsik 
Published: April 2007

Stratified exhaust gas recirculation (EGR) not only achieves reductions in NOx emissions and fuel consumption but also improves combustion stability for highly dilute mixtures. In this study, EGR stratification within a cylinder was completed by installing a fast-response solenoid valve in an EGR line and controlling its timing and duration. Lean burn of liquefied petroleum gas (LPG) with stratified EGR was examined to attain lower emissions and better fuel economy. The obvious stratification of EGR along the vertical distance from the spark plug was observed through a concentration measurement by a planar laser-induced fluorescence (PLIF) technique. Properly stratified EGR showed faster combustion and improved combustion stability for both stoichiometric and lean mixtures compared to those from homogeneous EGR. With a 30 per cent EGR rate, the peak heat release was 10 per cent higher, accompanied by a shorter combustion duration in the stratified EGR (SEGR) case than in the homogeneous EGR (HEGR) case. Addition of EGR into a lean mixture of λ=1.2 led to a further 3 per cent further reduction in fuel consumption, which was attainable only with stratified EGR but not with homogeneous EGR. More EGR could be admitted and NOx emission further reduced with less increase in hydrocarbon emission with stratified EGR than with homogeneous EGR. Those results are due to the dominance of stratified EGR over homogeneous EGR in combustion speed and stability.
Validation of engine combustion models against detailed in-cylinder optical diagnostics data for a heavy-duty compression-ignition engine
Authors: Singh S , Reitz R D , Musculus M P B , Lachaux T 
Published: April 2007

Three different approaches for modelling in-cylinder compression-ignition engine processes for partially premixed combustion modes are compared with experimentally observed cylinder pressure and in-cylinder images of liquid- and vapour-fuel penetration, ignition, combustion, and soot formation in an optically accessible heavy-duty direct injection engine. A multi-dimensional computational fluid dynamics model for engine combustion, KIVA-3V, served as a common platform into which three different combustion submodels were integrated: (1) characteristic time combustion (KIVA-CTC); (2) representative interactive flamelet (KIVA-RIF); and (3) direct integration using detailed chemistry (KIVA-CHEMKIN). Three different engine operating strategies with significant premixing of fuel and air prior to ignition were investigated: Low-temperature combustion achieved by charge dilution, with fuel injection either (1) early, or (2) late in the engine cycle, and (3) long ignition delay, high-temperature combustion (i.e. no charge dilution) with fuel injection near top dead centre of the piston stroke. Comparison of simulated cylinder pressure and heat-release rates with the experimental results shows that all the combustion submodels predict the cylinder pressures and heat-release rates reasonably well, but predictions of in-cylinder phenomena were significantly different among the submodels. The KIVA-CHEMKIN submodel predictions agree best with experimental observations of the location of ignition sites and the spatial distribution of soot and OH. The KIVA-RIF model, which uses global quantities to account for turbulence-chemistry interactions, under-predicts the flame lift-off, while ignition sites and species distributions are broader than observed experimentally. The KIVA-CTC submodel greatly over-predicts the spatial extent and total amount of in-cylinder soot.
Steam Alternating Solvent Process
Authors: Zhao L. 
Published: April 2007

Summary
A new heavy-oil-recovery process, the steam alternating solvent (SAS) process, is proposed and studied using numerical simulation. The process is intended to combine the advantages of the steam-assisted gravity drainage (SAGD) and vapor-extraction (va-pex) processes to minimize the energy input per unit oil recovered. The SAS process involves injecting steam and solvent alternately, and the basic well configurations are the same as those in the SAGD process.
Field-scale simulations were conducted to assess the SAS process performance under typical Cold Lake, Alberta, reservoir conditions. These results suggested that the oil-production rate of an SAS process could be higher than that of a SAGD process, while the energy input was 18% less than that of a SAGD process. By varying the length of the steam- and solvent-injection periods in a cycle, a different set of steam/oil and solvent/oil ratios may be obtained because the temperature profiles and solvent-concentration distributions in the vapor chamber can be affected by the injection pattern. The process therefore can be optimized for a specific reservoir under certain economic conditions.
Grid-System Requirements in Numerical Modeling of Pressure-Transient Tests in Horizontal Wells
Authors: Al-Mohannadi N. , Ozkan E. , Kazemi H. 
Published: April 2007

Summary
The common approach of using refined grids and small timesteps usually does not provide accurate and efficient numerical models to simulate horizontal-well pressure-transient tests. In most cases, this approach requires impracticably long computational times or creates artifacts on pressure and derivative responses that may be confused with the characteristics of certain flow regimes. This paper presents an investigation of the grid and timestep requirements for the conventional well index (WI) to provide accurate simulations of horizontal-well pressure-transient responses. The results of this study indicate that the conventional WI should be used with log-distributed grid and timesteps to obtain a closer match to the analytical solution at early times. There is a limit to grid refinement beyond which the results do not improve. For these cases, the transient well index (TWI) introduced in this paper allows larger grids while improving the accuracy of simulations, especially at early times.
Estimating Productivity-Controlling Parameters in Gas/Condensate Wells From Transient Pressure Data
Authors: Bozorgzadeh Manijeh , Gringarten Alain C. 
Published: April 2007

Summary
The ability to predict well deliverability is a key issue for the development of gas/condensate reservoirs. We show in this paper that well deliverability depends mainly on the gas relative permeabilities at both the endpoint and the near-wellbore saturations, as well as on the reservoir permeability. We then demonstrate how these parameters and the base capillary number can be obtained from pressure-buildup data by using single-phase and two-phase pseudopressures simultaneously. These parameters can in turn be used to estimate gas relative permeability curves. Finally, we illustrate this approach with both simulated pressure-buildup data and an actual field case.
A New-Generation LWD Tool With Colocated Sensors Opens New Opportunities for Formation Evaluation
Authors: Neville Thomas J. , Weller Geoff , Faivre Ollivier , Sun Haitao 
Published: April 2007

Summary
A new logging-while-drilling (LWD) tool that combines traditional measurements of gamma ray, propagation resistivity, gamma-gamma density, and thermal-neutron porosity with measurements unique to the LWD arena, including neutron capture spectroscopy and capture cross section, opens up new opportunities for formation evaluation on LWD.
The compact design of the new-generation LWD tool greatly increases the likelihood that measurements will be made before the onset of significant invasion. The colocation of resistivity- and neutron-based sensors also means that key measurements are being made at the same depth at the same time and on a similar volume of the formation. These features ensure that all measurements are essentially seeing the same amount of invasion, thus removing a major complication in conventional LWD interpretation.
Cyclical endometrial steroid hormone receptor expression and proliferation intensity in the mare
Authors: Aupperle H. , Özgen S. , Schoon H.‐A. , Schoon D. , Hoppen H.‐O. , Sieme H. , Tannapfel A. 
Published: April 2007

SummaryThe aims of this study were to investigate the steroid hormone receptor expression and the proliferation intensity during the equine endometrial cycle by immunohistological methods, established for routine examination of formalin‐ fixed, paraplast‐embedded specimens. Endometrial biopsy specimens were obtained during one cycle from 7 mares. In comparison with the blood steroid hormone levels the quantity and distribution of oestrogen (ER) and progesterone receptors (PR) and the proliferation marker Ki‐67 antigen expression were investigated. Rising 17β‐oestradiol concentrations in preoestrus induce a synchronous expression of ER, PR and Ki‐67 antigen in stromal cells. In the early dioestrus 17β‐oestradiol levels decrease and progesterone levels reach their maxima. This correlates with an intense proliferation activity and the highest hormone receptor expression in epithelial cells. In accordance to the morphological features of asynchronous glandular differentiation in fibrotic areas (endometrosis) their epithelial hormone receptor expression is out of phase.
Effect of age and training on murmurs of atrioventricular valvular regurgitation in young Thoroughbreds
Authors: Young L. E. , Wood J. L. N. 
Published: April 2007

SummaryCardiac auscultation was carried out on 111 Thoroughbred horses age 2–5 years to test the hypothesis that athletic training might influence the development of atrioventricular (AV) valve regurgitation in young Thoroughbreds. Murmurs of valvular regurgitation were identified and graded on a 1–6 scale. There were 2 sources of auscultation data: 1) 55 2‐year‐old horses that were examined by auscultation before training commenced and 9 months later when at race fitness; 2) 56 horses age 2–5 years that were examined on one occasion only (25 2‐year‐olds, 23 3‐year‐olds, five 4‐year‐olds and five 5‐year olds). All horses in the second data set were in full training and racing regularly at the time of the examination. To conclude the study, 35 horses were selected randomly from both groups of horses and examined with colour‐flow Doppler echocardiography. The aim of the final part of the study was to check specificity and sensitivity of auscultation for detection of AV valve murmurs and therefore validate the auscultation findings.Priorto training, the prevalence in 2‐year‐old racehorses of murmurs of mitral regurgitation and tricuspid regurgitation was 7.3% (4/55) and 12.7% (7/55), respectively. After training, the prevalence proportions increased to 21.8% (12/55) and 25.5% (14/55). After training, one horse developed a murmur characteristic of aortic regurgitation. The differences in murmur prevalence were statistically significant for mitral and tricuspid regurgitation (pairedttest results: mitral regurgitation, P = 0.019; tricuspid regurgitation, P = 0.007), as were the differences in mean murmurgrade (P= 0.018 and P= 0.0006, respectively). There were no significant effects of age on the prevalence of valvular regurgitation in 56 horses examined at race fitness. Auscultation was a specific (specificity 100%) and reasonably sensitive method for detection of murmurs of mitral and tricuspid regurgitation (mitral regurgitation: positive predictive value 100%, negative predictive value 84%, tricuspid regurgitation: positive predictive value 100%, negative predictive value 65%).These data suggest that the prevalence and grade of murmurs of mitral and tricuspid valvular regurgitation increase in 2‐year‐old Thoroughbreds after 9 months of athletic training. Whereas the effects of age and growth on the prevalence of murmurs cannot be ruled out from these data, this study suggests that there is an influence of athletic training on the development of atrioventicular valvular regurgitation in flat‐racing Thoroughbreds.
Equine dental disease Part 4: a long‐term study of 400 cases: apical infections of cheek teeth
Authors: Dixon P. M. , Tremaine W. H. , Pickles K. , Kuhns L. , Hawe C. , Mccann J. , Mcgorum B. C. , Railton D. I. , Brammer S. 
Published: April 2007

SummaryOf 400 horses referred because of equine dental disease, 162 suffered from primary apical infections of their cheek teeth (CT), including 92 with maxillary CT infections and 70 with mandibular CT infections. Maxillary swellings and sinus tracts were more common (82 and 26% incidence, respectively) with infections of the rostral 3 maxillary CT, than with infections of the caudal 3 maxillary CT(39 and 5% incidence, respectively). Nasal discharge was more commonly present with caudal (95%) than rostral (23%) maxillary CT infections. Mandibular CT apical infections commonly had mandibular swellings (91%) and mandibular sinus tracts (59%) and these infections were closely related to eruption of the affected CT. A variety of treatments, including medical treatment, apical curettage, repulsion and oral extraction of affected teeth were utilised in these cases, with oral extraction appearing to be most satisfactory. Infections of caudal maxillary CT with a secondary paranasal sinusitis were most refractory to treatment, with a complete response to the initial treatment achieved in just 33% of these cases. Most other cases responded fully to their initial treatment. The long‐term response to treatment was good in most cases.