bluuebunny/crossref_metadata_2025_split huggingface dataset:
Renal artery velocity mapping with MR imaging
Authors: Maier Stephan E. , Scheidegger Markus B. , Liu Kecheng , Schneider E. , Bellinger A. , Boesiger Peter 
Published: March 2007

AbstractAn MR phase imaging sequence with a very short echo time was used to assess blood velocity and flow at the renal artery bifurcation. Cardiac‐gated MR imaging data were obtained in six healthy subjects in sagittal planes adjacent to the abdominal aorta and transverse planes above and below the renal artery bifurcation. Average renal artery flow rate was 23.8 ±9 mL/sec. A strong individual variability was found for the velocity profiles in the abdominal aorta during end‐systolic regurgitation. Flow rate was also determined in three patients with reduced renal artery blood flow. Two patients received therapy with percutaneous transluminal angioplasty. The successful outcome was documented with MR imaging. A reliable assessment of renal artery flow with MR phase imaging is feasible. Measurement of the velocity profiles yields valuable insights in the complicated flow regime at the renal artery bifurcation.
Cardiac imaging: Comparison of two‐shot echo‐planar imaging with fast segmented k‐space and conventional gradient‐echo cine acquisitions
Authors: Leung Daniel A. , Debatin Jörg F. , Wildermuth Simon , McKinnon Graeme C. , Von Schulthess Gustav K. 
Published: March 2007

AbstractWe compared the cardiac image quality of multishot echo‐planar imaging (EPI), segmented K‐space, and conventional cine acquisitions. Three techniques were used to obtain gated multiphase acquisitions of an axial section traversing both ventricles in 10 volunteers: two‐shot EPI acquired nonsequentially over two heart beats breath‐held segmented K‐space cine with eight K‐space lines acquired per cardiac trigger over 16 R‐R intervals, also breath‐held and 24 cine phases obtained over 256 R‐R intervals. Intraventricular SNRs with two‐shot EPI were superior to segmented K‐space cine acquisitions (P <.005) and not statistically different from conventional cine acquisitions (P <. 1). Intraventricular signal was most homogeneous on conventional cine images (P <.05). Coronary artery visualization and myocardial delineation were better on the EPI image set than on segmented K‐space cine images (P <.05). Two‐shot EPI provides high‐quality gated cardiac images with an acquisition time of only 2 seconds.
Polo‐like kinase 1 may regulate G2/M transition of mouse fertilized eggs by means of inhibiting the phosphorylation of Tyr15 of Cdc2
Authors: Zhang Zhe , Su Wen‐hui , Feng Chen , Yu Da‐hai , Cui Cheng , Xu Xiao‐yan , Yu Bing‐zhi 
Published: March 2007

AbstractPolo‐like kinase 1(Plk1) has been reported to be a multifunctional kinase that plays pivotal regulatory roles in microtubule assembly during mammalian early embryonic mitosis. In the present study, we examined the expression of Plk1 at protein and mRNA level in mouse fertilized eggs by Western blot and RT‐PCR. We also examined the kinase activity of Plk1. At various developmental phases of mouse one‐cell stage embryos, both the protein and the mRNA of Plk1 were uniformly distributed; but the kinase activity of Plk1 increased at G2/M phase and decreased at the end of M phase. At the meantime, the phosphorylation of Tyr15 of Cdc2 was inhibited at M phase. To investigate its function in mammalian fertilized eggs further, we used specific short hairpin RNAs (shRNA) and scytonemin, the putative inhibitor of Plk1 to suppress the activity of Plk1 in mouse fertilized eggs. Upon blockage of the activation of with Plk1 shRNA and scytonemin in mouse one‐cell stage embryos, the cleavage rate decreased and the phosphorylation level of Tyr15 of Cdc2 increased. These results imply that the Plk1 may regulate cell cycle progression of mouse fertilized eggs by means of inhibiting the phosphorylation of Tyr15 of Cdc2. Mol. Reprod. Dev. 74: 1247–1254, 2007. © 2007 Wiley‐Liss, Inc.
p19Ink4d and p18Ink4c cyclin‐dependent kinase inhibitors in the male reproductive axis
Authors: Buchold Gregory M. , Magyar Patricia L. , Arumugam Ramamani , Lee Mary M. , O'Brien Deborah A. 
Published: March 2007

AbstractThe loss of the cyclin‐dependent kinase inhibitors (CKIs) p18Ink4c and p19Ink4d leads to male reproductive defects (Franklin et al., 1998. Genes Dev 12: 2899–2911; Zindy et al., 2000. Mol Cell Biol 20: 372–378; Zindy et al., 2001. Mol Cell Biol 21: 3244–3255). In order to assess whether these inhibitors directly or indirectly affect male germ cell differentiation, we examined the expression of p18Ink4c and p19Ink4d in spermatogenic and supporting cells in the testis and in pituitary gonadotropes. Both p18Ink4c and p19Ink4d are most abundant in the testis after 18 days of age and are expressed in purified populations of spermatogenic and testicular somatic cells. Different p18Ink4c mRNAs are expressed in isolated spermatogenic and Leydig cells. Spermatogenic cells also express a novel p19Ink4d transcript that is distinct from the smaller transcript expressed in Sertoli cells, Leydig cells and in other tissues. Immunohistochemistry detected significant levels of p19Ink4d in preleptotene spermatocytes, pachytene spermatocytes, condensing spermatids, and Sertoli cells. Immunoprecipitation‐Western analysis detected both CKI proteins in isolated pachytene spermatocytes and round spermatids. CDK4/6‐CKI complexes were detected in germ cells by co‐immunoprecipitation, although the composition differed by cell type. p19Ink4d was also identified in FSH+ gonadotrophs, suggesting that this CKI may be independently required in the pituitary. Possible cell autonomous and paracrine mechanisms for the spermatogenic defects in mice lacking p18Ink4c or p19Ink4d are supported by expression of these CKIs in spermatogenic cells and in somatic cells of the testis and pituitary. Mol. Reprod. Dev. 74: 997–1007, 2007. © 2007 Wiley‐Liss, Inc.
Publication Committee Meeting HUPO 5th Annual World Congress Long Beach, CA, USA 30 October 2006
Authors: Orchard Sandra , Heck Albert , Uhlen Mathias , Ping Peipei 
Published: March 2007

AbstractThis meeting brought together delegates from industry, academia and the publishing houses to facilitate discussions on the level of support from the journals for the use of standardised data formats and their interest in the creation of a network of proteomics repositories collaborating on a coordinated data curation effort. Discussions centred on how best to structure interactions between journals, databases and researchers to improve accessibility to data, and facilitate comparisons between datasets.
The numerical analysis of pressure‐flow curves in infancy
Authors: Stocks Janet , Thomson Anne , Silverman Michael 
Published: March 2007

AbstractLung resistance (RL) and airway resistance (Raw) were measured in 33 healthy and sick infants. Using strict criteria for quality control, calibrated pressure‐flow (P‐V) curves were produced with the aid of a computer so that resistance could be analyzed at several points over the breathing cycle. In a subgroup of 11 infants from whom simultaneous measurements were obtained, values of RL and Raw were comparable, suggesting that the tissue component may make only a minimal contribution to lung resistance in infants. For both RL and Raw, the P‐V relationship remained linear up to 50% maximum inspiratory flow in all infants. At other points of the respiratory cycle, there were marked changes in resistance, values calculated between points of mid‐isovolume or peak pressure being significantly higher than those measured over the linear portion of inspiratory flow. While no single value can accurately reflect the changes in respiratory resistance that occur during the breathing cycle, the authors suggest that for purposes of comparison, RL or Raw should be measured as the slope of the inspiratory loop from the origin up to 50% of maximum inspiratory flow. From a calibrated tidal pressure flow curve values of resistance over other portions of the breathing cycle can easily be determined.
The effect of age on pulmonary epithelial permeability in unanesthetized lambs
Authors: Hutchison Arlene A. , McNicol Kenneth J. , Loughlin Gerald M. 
Published: March 2007

AbstractPulmonary epithelial permeability was measured 1) in unanesthetized sheep, and 2) longitudinally in growing lambs. Awake sheep were intubated and a solution of 51Cr‐ethylenediaminetetraacetic acid and 125I‐antipyrine was instilled in the intrathoracic trachea via the nasotracheal tube. Arterial blood was drawn 1–25 minutes after the instillation. The ratios of the counts of 51Cr to 125I at 7, 10, and 13 min were calculated and averaged for each animal. Data from six adult sheep showed that the mean ± SE of the permeability ratio was 0.012 ± 0.003 and was reproducible over three months. When measured twice within two hours, the second ratio was significantly higher than the first (0.021 ± 0.004 vs. 0.011 ± 0.003, n = 6, P < 0.05). One hour of general anesthesia with methoxyflurane did not alter the permeability ratio significantly. Ten lambs were studied longitudinally 10 hours and 5, 10, 20, and 30 days after delivery. Within the first 24 hours of life the permeability ratio was 0.035 ± 0.007, significantly greater (P < 0.05) than the adult value. At five days there was no significant difference between lambs and adult sheep. Throughout the first month of life, the permeability ratio in lambs remained at the adult level. In summary, 1) pulmonary epithelial permeability can be assessed in awake lambs and adult sheep, 2) the permeability ratio is reproducible for three months but should not be measured within two hours, 3) newborn lambs have a significantly higher ratio than older lambs or adult sheep, and 4) the ratio reaches the adult level within five days after birth.
The effect of systemic hydration on normal and impaired mucociliary function
Authors: Marchette L. C. , Marchette B. E. , Abraham W. M. , Wanner A. 
Published: March 2007

AbstractWhether systemic hydration enhances the clearance of lower airway secretions in normal lungs and in lungs during antigen‐induced bronchial obstruction was studied. In five conscious allergic sheep, tracheal mucus velocity (TMV) as an index of lower airway mucociliary clearance was measured before and serially for 60 minutes following intravenous infusion of 5% dextrose solution at volumes ranging from 5 to 35 ml/kg. None of these fluid regimens had a significant effect on TMV, although there was a tendency toward a slowing of TMV at the higher volumes of 25 and 35 ml/kg. After producing an acute allergic airway response by inhalation challenge with specific antigen, there was a decrease in mean TMV by 27% and 15% before sham infusion and infusion of 35 ml/kg of dextrose solution, respectively. During the subsequent 60‐minute observation period, mucociliary transport was further impaired by dextrose infusion, with mean TMV being lower after dextrose infusion than after sham infusion at all times of measurement (P < 0.05). The lowest value was reached 30 minutes after dextrose infusion (45% of control). It was concluded that systemic hydration does not significantly alter airway mucociliary transport in the normal state but further impairs mucociliary transport during allergic mucociliary dysfunction. This raises questions regarding the therapeutic role of systemic hydration in the treatment of children and adults who have bronchial asthma.
Respiratory resistance and impedance magnitude in healthy children aged 2–18 years
Authors: Solymar L. , Aronsson P‐H. , Bake B. , Bjure J. 
Published: March 2007

AbstractTwo hundred eighteen healthy children aged 2 to 18 years were studied using a modification of the forced oscillation technique. Reference values with height as predictor were determined for total respiratory resistance and impedance during inspiration, expiration, and throughout the whole respiratory cycle at an oscillation frequency of 4 Hz and, in a subpopulation of 61 children, at frequencies of 2 and 12 Hz. Mean total inspiratory resistance, determined at 4 Hz, decreased with growth from 1.3 kPa.1−1.s at 2 years of age to 0.3 kPa.1−1.s at 18 years. Variability in the results between individuals, expressed in terms of coefficient of variation, was found to be +27% and −21%, respectively, and within individuals, 9%. Resistance during expiration was on average 16% higher than during inspiration and the variability within individuals was 11%. A marked decrease in resistance was found in small children when the frequency was increased from 2 to 12 Hz. The frequency dependence of respiratory resistance observed in small children changes gradually with growth, in parallel with the reduction of total respiratory resistance, to an adult pattern in which no significant change in resistance can be noted between frequencies of 2 and 12 Hz.
The diagnostic effectiveness of the flexible bronchoscope in children
Authors: Wood Robert E. 
Published: March 2007

AbstractOver a 5‐year period 1,000 pulmonary endoscopic procedures (172 laryngoscopies, 828 bronchoscopies) were performed in children less than 10 years of age using flexible fiberoptic bronchoscopes, with sedation and topical anesthesia. An endoscopic diagnosis of direct relevance to the primary indication for the procedure was established in 76% of the cases; in an additional 15%, abnormalities relevant to a secondary indication were found. Findings were normal in 9% of the cases. The bronchoscope was most useful in the evaluation of patients who had stridor, atelectasis, persistent wheezing, or a suspected foreign body for which there was insufficient evidence to warrant open‐tube bronchoscopy, and for patients who had tracheostomies. The high diagnostic yield and low complication rate strongly support the use of the flexible bronchoscope in the diagnostic evaluation of infants and children who have a variety of pulmonary problems.
Chronic lung disease in children referred to a teaching hospital
Authors: Fernald Gerald W. , Denny Floyd W. , Fairclough Diane L. , Helms Ronald W. , Volberg Frank M. 
Published: March 2007

AbstractEtiology, symptomatology, and host factors were studied in 184 children referred to a teaching hospital for evaluation in an attempt to classify chronic or potentially chronic lung disease. A standardized historical questionnaire, physical findings, chest radiographs, and a laboratory panel identified a diagnosis that could be related directly or indirectly to chronic lung disease in 22% of the subjects. Among the remaining 78%, bronchiectasis was found in 9%, chronic pneumonia in 9%, chronic diseases with wheezing in 56%, and no significant lower respiratory disease in 4%. Analysis of cases with no apparent etiology revealed that the majority of patients had historical evidence of wheezing; often this previously had not been appreciated. Laboratory tests, such as eosinophil count and immunoglobulin E (IgE) testing, did not differentiate between wheezing and nonwheezing patients. Spirometric evaluation was limited because most subjects were younger than 5 years old. For the same reason, testing for bronchial hyperreactivity was not done. This study reemphasizes that wheezing is a major symptom of chronic lung disease in childhood and provides an outline for its evaluation. Although clinical airways reactivity, as exemplified by wheezing, proved to be the most prominent host defect found in this study, its nature, genetic or otherwise, remains to be defined.
Fetal lung fluid response to maternal hyperosmolality
Authors: Ross Michael G. , Leake Rosemary D. , Ervin PhD M. Gore , Fisher Delbert A. 
Published: March 2007

AbstractLung fluid production in utero, a significant source of amniotic fluid, may be regulated by the fetus in response to environmental stress. We monitored changes of maternal and fetal plasma osmolality, plasma arginine vasopressin level, and fetal lung fluid production in response to mannitol‐induced change in maternal osmolality in five chronically catheterized ovine fetuses. Four additional ewes and their fetuses did not receive mannitol and served as controls. Maternal infusion of 20% mannitol resulted in maternal and subsequent fetal hyperosmolality (changing from 303 ± 2 to 322 ± 2 mOsm and 300 ± 5 to 312 ± 8 mOsm, respectively). Mean fetal lung fluid production significantly decreased (from 2.6 ± 0.4 to 1.6 ± 0.4 ml/10 min), whereas lung fluid osmolality significantly increased (from 298 ± 2 to 303 ± 3 mOsm) in the study animals. No changes in lung fluid sodium or potassium concentrations were observed in study or control fetuses. Fetal plasma arginine vasopressin level significantly increased in the study fetuses (2.2 ± 0.3 to 5.3 ± 1.6 μU/ml), though not in control animals. These results indicate that the fetal lamb responds to increased osmolality by decreasing lung fluid production, and that there is a concomitant increase in lung fluid osmolality. This response appears to be mediated via increased fetal plasma vasopressin levels.
Traumatic bronchial injuries in children
Authors: Ein Sigmund H. , Friedberg Jacob , Shandling Barry , Fearon Blair , Filler Robert M. 
Published: March 2007

AbstractBetween 1975 and 1981 five children (three girls and two boys) from 3 to 11 years were treated for blunt chest trauma with major tears in two areas of the right main bronchus. All were hit or run over by motor vehicles and were in acute respiratory distress. All suffered right pneumothoraces; three did not respond to a chest tube with suction. Four of five children had subcutaneous emphysema, and two had fractured ribs on the ipsilateral side; three children also had contralateral chest injuries. Four had major extrathoracic injuries. Three children required early repair, while two needed late treatment. All five patients recovered well and have remained healthy from 5 to 10 years after injury. These cases serve as illustrations for a review of a survey of the literature.
Oxygen and resolution of lung injury
Authors: Tyler Donald C. , Pavlin D. Janet , Boatman E. S. , Nessly Michael , Cheney Frederick W. 
Published: March 2007

AbstractWe investigated the effects of varying inspired oxygen concentrations on the resolution of oleic acid‐induced lung injury in rabbits. Rabbits were injected intravenously with oleic acid and maintained in room air, or exposed to 60, 70, or 80% oxygen for periods of 7 or 10 days. Oleic acid caused hemorrhagic pulmonary edema with hypoxemia. Hypoxemia was more profound in the oxygen‐treated animals, a difference that was significant after 7 days' exposure to 60 and 70% oxygen, and after 4 days to 80% oxygen. Mortality was increased in the animals maintained in 80% oxygen. The data suggest that environmental oxygen concentrations greater than 60% interfere with the return to normal lung function following oleic acid injury in rabbits. The hypoxemia may be due to either mismatching of ventilation and perfusion or to a diffusion block resulting from the increased septal width. There was no evidence of massive pulmonary edema as a cause of the hypoxemia. It was not possible to distinguish between injury primarily caused by oxygen and its interference with the healing process.
Ventilatory response to increased dead spaces in the first week of life
Authors: Stokes G. M. , Carman P. G. T. , Milner A. D. , Morgan D. B. , Wilson A. J. , Oliver M. R. 
Published: March 2007

AbstractWe have developed a method for quantitatively assessing respiratory control in a group of 10 full‐term healthy babies, mean age at test 5 days, by measuring their ventilatory response to added external dead spaces. The dead spaces were equal to 0.5, 1, 2, and 3 anatomic dead spaces (2.2 ml/kg body weight), respectively. Tidal volumes were measured by a nasal mask and a 200‐I rigid container. End‐tidal CO2 was monitored via a tube in the nostril by a mass spectrometer. Baseline measurements were made during a 10‐minute period, after which similar recordings were obtained with each of the dead space tubes. The system was calibrated against a 20‐ml syringe. The mean baseline ventilation was 602 ml/minute. On the addition of 0.5, 1, 2, and 3 dead spaces, minute ventilations were increased by 37.5, 74.7, 150.7, and 273.6%, respectively. These increases were due to rises in tidal volume rather than respiratory rate. End‐tidal CO2 rose by 1.8 and 4 mmHg on the addition of 2 and 3 dead spaces. When the results were compared with expected minute ventilations—based on the baseline recordings and corrected for the added dead spaces and for changes in anatomic dead space ventilation due to alterations in respiratory rate—the results were within 10% of expected values.
Effect of endotracheal continuous positive airway pressure on sensitivity to carbon dioxide and on respiratory timing in preterm infants
Authors: Krauss Alfred N. , Goldstein Ricki F. , Alfero Veronica , Prayer William W. , Auld Peter A. M. 
Published: March 2007

AbstractTo determine the effects of continuous positive airway pressure (CPAP) on ventilatory response to CO2 and inspiratory and expiratory duration in preterm infants, 24 preterm infants with an averase birth weight of 1220 g were studied at a mean age of 10.6 days. CPAP was applied via an uncuffed endotracheal tube. Testings were performed between ambient pressure and a positive airway pressure of 10 cm H2O. Approximately 2/3 of the applied pressure was transmitted to the esophagus. All infants demonstrated a ventilatory response to carbon dioxide of less than 50 ml/min per mm Hg Pco2 at ambient pressure, and no infant showed significant improvement at increasing levels of CPAP. Drive to breathe, as reflected in the inspiratory flow rate (Vt/Ti) also failed to change significantly. It may be concluded that in the apparent absence of significant changes in lung volume, CPAP fails to increase sensitivity to CO2 in preterm infants recovering from hyaline membrane disease.
In vivo response times for a heated skin surface CO2 electrode during rest and exercise
Authors: Nickerson Bruce G. , Patterson Christopher , McCrea Ray , Monaco Frank 
Published: March 2007

AbstractThe continuous, noninvasive estimation of arterial carbon dioxide tension (PaCO2) by heated skin surface electrodes has recently become available for pediatric patients. Skin surface (PsCO2) electrodes can enhance the safety of procedures such as intubation, bronchoscopy, ventilator changes, sleep studies, or measurement of the ventilatory response to CO2 or hypoxia. However, clinical situations that include rapid changes in PaCO2 demand knowledge of the in vivo response time. We compared the response of a heated PsCO2 electrode to end tidal CO2 (PetCO2) during abrupt changes in inspired CO2 from room air to 7% CO2 and back to room air. We obtained 54 curves on nine healthy subjects. There was an initial lag time with less than a 10% change in PsCO2. Then PsCO2 approached PetCO2 exponentially. For subjects at rest changing from breathing room air to 7% CO2, the initial lag time was 46 ± 2 seconds and the 50% response time of the exponential portion was 46 ± 3 seconds. Thus, it took 86 seconds for the electrode to record a 60% response to an abrupt increase in inspired CO2. The initial lag and 50% response time were considerably shorter during exercise (30 ± 2 and 33 ± 2 seconds) and even shorter when switched from breathing 7% CO2 to room air (23 ± 2 and 21 ± 2 seconds). Exercise did not further reduce the response time when CO2 was initially elevated, suggesting the faster response time was due to vasodilation of the skin due to elevated CO2. Users of such electrodes should be aware that changes in ventilation will not be reflected by the CO2 electrode for at least one minute and reaching equilibrium takes several minutes.