bluuebunny/crossref_metadata_2025 huggingface dataset:
Interaction of processes and importance of contourites: insights from the detailed morphology of sediment Drift 7, Antarctica
Authors: Rebesco M. , Camerlenghi A. , Volpi V. , Neagu C. , Accettella D. , Lindberg B. , Cova A. , Zgur F. ,   Magico Party
Published: December 2007

As the definition of contourites has widened to embrace a large spectrum of sediments in so-called mixed systems, the distinction between contourites and turbidites has become at times vague. The case history of sediment Drift 7 off the Antarctic Peninsula is analysed in this paper in the light of newly acquired swath bathymetry data. The co-existence of various sedimentary processes is reflected in a complex morphology: erosional gullies produced by debris flows on the upper part of the continental slope; deeply incised channels at the slope base; main trunk-type inter-drift turbidity channels separating the drifts; slide scars; undulating depositional bedforms interpreted as bottom-current sediment waves; fluid escape structures perhaps associated with deep-water coral bioherms. The data suggest that Drift 7 is a genuine sediment drift in which bottom currents pirate the sediment of the turbidity currents. Finally, we propose that the control on location and elongation of the drift is inherited from an older margin structure. The relationships between bottom current and deposition are investigated through a comparison with the SE Greenland continental margin, an analogous counterpart in the northern hemisphere.
Santos Drift System: stratigraphic organization and implications for late Cenozoic palaeocirculation in the Santos Basin, SW Atlantic Ocean
Authors: Duarte Cláudio S. L. , Viana Adriano R.
Published: December 2007

High-quality 2D and 3D seismic data were analysed to investigate the stratigraphic organization of the sedimentary deposits and the impact of the palaeocirculation of the SW Atlantic Ocean in the construction of the Santos Basin slope from late Palaeogene to Recent time. Seven seismic sequences were identified based on their external geometry, internal seismic pattern and seismic boundaries. A correlation between these sequences, the glacio-eustatic curves and the major climatic-palaeoceanographic events was attempted. The base of the studied sequences is the
c.
28 Ma intra-Oligocene Rupelian-Chatian unconformity. Six other seismic horizons corresponding to the sequence boundaries were mapped ranging from the late Oligocene to the Pliocene. Variations in the bottom-current intensity were characterized by the seismic pattern of each sequence and by the evolution of margin physiography. A 100 km long channel-like gutter, the Santos Channel, was excavated at the foot of an intra-slope escarpment. It was the locus of major flow circulation until the middle Miocene, when the margin physiography reorganization transferred the main axis of deep current action downslope and excavated the São Paulo Channel at the foot of the present continental slope. Two major contourite drifts were accumulated in response to the different combinations of bottom-current axis position and slope physiography. Those drifts constitute the Santos Drift System. Conversely to the present-day circulation pattern, with southward flow above the slope dominated by the western boundary Brazil Current, both at surface and deep waters, the geological record indicates that the palaeocirculation in the Santos Basin was marked by the opposite sense of circulation of surface waters (southward palaeo Brazil Current) and of the intermediate to deep waters (northward Southern Ocean Current). The study indicates that periods of relative sea-level rise to highstands correspond to increase in drift accumulation whereas during lowstands slope drift sedimentation is reduced.
Mediterranean bottom-current deposits: an example from the Southwestern Adriatic Margin
Authors: Verdicchio Giuseppe , Trincardi Fabio , Asioli Alessandra
Published: December 2007

The identification of bottom-current deposits is a key to understanding the long-term deep-sea circulation and its changes through geological times. The Southwestern Adriatic Margin (SAM) is a small Mediterranean sub-basin that represents a key site to study bottom-current deposits in a Mediterranean context and hence to improve our knowledge of changes in Mediterranean deep-water circulation during the recent geological past. The SAM is characterized by complex stratification and circulation related to an interaction between two south-flowing bottom water masses: the cold North Adriatic Dense Water (NAdDW), formed in the shallow northern Adriatic through cold wind forcing and winter heat loss, and the highly saline Levantine Intermediate Water (LIW), generated in the Eastern Mediterranean through intense evaporation and flowing along the slope in a depth range of 200–600 m. Chirp-sonar profiles, TOBI mosaics and sediment cores acquired along the SAM reveal distinctive sediment drift types (elongated, plastered and isolated drifts) and extensive fields of sediment waves. Non-depositional and erosional features related to bottom-current activity include moats between drifts and the steep slope, widespread upper-slope erosional areas and extensive furrowed areas, which are particularly developed where change in slope orientation blocks the current circulation. The distribution, morphology and size of bottom-current features along the SAM result from an interaction between current regime and slope morphology, characterized by structural highs perpendicular to the slope contour (e.g. Dauno Seamount), multiple slope incisions (e.g. Bari Canyon and slump scars) and extensive block-slide deposits. Morphobathymetric and seismic stratigraphic data on the SAM show that bottom-current deposits are best developed where the regional slope flattens seaward of a very steep, often erosional, upper slope. The roughness of the lower slope, in particular, seems to correlate with the complexity and decreasing size of the bottom-current deposits. Like other land-locked basins, the Adriatic underwent dramatic palaeogeographical and palaeoceanographic rearrangements during the Late Quaternary sea-level oscillations. Indeed, during the Last Glacial Maximum (LGM), most of the areas where NAdDW is formed today were subaerially exposed. Concurrently, during glacial times the LIW production was probably reduced compared with the present-day conditions. The SAM slope is a key site to study the impact of changing current regime on late Quaternary slope deposits. Other Mediterranean late Quaternary contourite deposits are either in water depths compatible with the LIW, particularly in the case of shallow sill basins (e.g. Sicily, Corsica Channel), or at the slope base reflecting the flow of Mediterranean deep waters. The SAM bottom-current deposits, instead, seems to record the changing interaction between two distinctive bottom-hugging currents along the same pathway.
Small mounded contourite drifts associated with deep-water coral banks, Porcupine Seabight, NE Atlantic Ocean
Authors: Van Rooij D. , Blamart D. , Kozachenko M. , Henriet J.-P.
Published: December 2007

Numerous studies on sediment drifts have demonstrated a close interaction between sea-bed morphology, palaeoceanography, sediment supply and climate. Contourites have been reported in areas along continental margins directly influenced by the effect of intensive deep-water currents from the global conveyor belt. In this paper, we report the occurrence of a small-scale confined contourite drift from Porcupine Seabight, SW of Ireland, and its association with a province of coral banks. The Porcupine Basin is a relatively shallow, semi-enclosed basin characterized by the presence of cold-water coral bank provinces. These coral banks are often associated to a strong northward-flowing bottom current, created and steered by a complex interaction of the water mass characteristics, tidal influences and sea-bed morphology. Very high-resolution seismic stratigraphy allowed the identification of a small mounded drift, located between a depression created by (1) an irregular palaeotopography caused by a vigorous Late Pliocene erosion event and (2) a north-south alignment of coral banks. Core MD99-2327, taken on the flank of this drift mound, shows the variability of the bottom currents. Sortable silt data show several periods of bottom-current enhancement, which may be linked with warmer periods and an inferred influx of Mediterranean Outflow Water. The glacial part of the core has been interpreted as a muddy contourite with a high content of ice-rafted debris. The lower part of the core is a deep-water massive contourite sand resembling the present-day sea-floor sediments.
Practical application of fundamental concepts in exercise physiology
Authors: Ramsbottom R. , Kinch R. F. T. , Morris M. G. , Dennis A. M.
Published: December 2007

The collection of primary data in laboratory classes enhances undergraduate practical and critical thinking skills. The present article describes the use of a lecture program, running in parallel with a series of linked practical classes, that emphasizes classical or standard concepts in exercise physiology. The academic and practical program ran under the title of a particular year II module named Sports Performance: Physiology and Assessment, and results are presented over a 3-yr period (2004–2006), based on an undergraduate population of 31 men and 34 women. The module compared laboratory-based indexes of endurance (e.g., ventilatory threshold and exercise economy) and high-intensity exercise (e.g., anaerobic power), respectively, with measures of human performance (based on 20-m shuttle run tests). The specific experimental protocols reinforced the lecture content to improve student understanding of the physiological and metabolic responses (and later adaptations) to exercise. In the present study, the strongest relationship with endurance performance was the treadmill velocity at maximal aerobic power ( r = +0.88, P < 0.01, n = 51); in contrast, the strongest relationship with high-intensity exercise performance was the mean power output (in W/kg) measured during a 30-s all-out cycle ergometer sprint ( r = +0.80, P < 0.01, n = 48). In class student data analysis improved undergraduate indepth or critical thinking during seminars and enhanced computer and data presentation skills. The endurance-based laboratories are particularly useful for examining the underlying scientific principles that determine aerobic performance but could equally well be adapted to investigate other topics, e.g., differences in the exercise response between men and women.
Becoming a truly helpful teacher: considerably more challenging, and potentially more fun, than merely doing business as usual
Authors: Jason Hilliard
Published: December 2007

Few medical faculty members are adequately prepared for their instructional responsibilities. Our educational traditions were established before we had research-based understandings of the teaching-learning process and before brain research began informing our understandings of how humans achieve lasting learning. Yet, there are several advantages you may have. If your expertise is at one of the frontiers of human biology, your teaching can be inherently fascinating to aspiring health professionals. If your work has implications for human health, you have another potential basis for engaging future clinicians. And, thanks to Claude Bernard's influence, you likely are “process oriented,” a necessary mindset for being an effective teacher. There are also challenges you may face. Your medical students will mostly become clinicians. Unless you can help them see connections between your offerings and their future work, you may not capture and sustain their interest. To be effective, teachers, like clinicians, need to be interactive, make on-the-spot decisions, and be “emotional literate.” If you aren't comfortable with these demands, you may have work to do toward becoming a truly helpful teacher. Program changes may be needed. Might your program need to change 1) from being adversarial and controlling to being supportive and trust based or 2) from mainly dispensing information to mainly asking and inviting questions? In conclusion, making changes toward becoming a truly helpful teacher can bring benefits to your students while increasing your sense of satisfaction and fulfillment as a teacher. If you choose to change, be gentle with yourself, as you should be when expecting your students to make important changes.
Students’ conceptions of underlying principles in medical physiology: an interview study of medical students’ understanding in a PBL curriculum
Authors: Fyrenius Anna , Silén Charlotte , Wirell Staffan
Published: December 2007

Medical physiology is known to be a complex area where students develop significant errors in conceptual understanding. Students’ knowledge is often bound to situational descriptions rather than underlying principles. This study explores how medical students discern and process underlying principles in physiology. Indepth interviews, where students elaborated on principles related to blood pressure and blood pressure regulation, were carried out with 16 medical students in a problem-based learning curriculum. A qualitative, phenomenographic approach was used, and interviews were audiotaped, transcribed, qualitatively analyzed, and categorized. Four categories were outlined. The underlying principles were conceived as follows: 1) general conditions for body function at a specified time point, 2) transferable phenomena between organ systems and time points, 3) conditionally transferable phenomena between organ systems and time points, and 4) cognitive constructions of limited value in medical physiology. The results offers insights into students’ thinking about underlying principles in physiology and suggest how understanding can be challenged to stimulate deep-level processing of underlying principles rather than situational descriptions of physiology. A complex conception of underlying principles includes an ability to problemize phenomena beyond long causal reasoning chains, which is often rewarded in traditional examinations and tests. Keywords for problemized processing are as follows: comparisons, differences, similarities, conditions, context, relevance, multiple sampling, connections, and dependencies.
Role of TTX-Sensitive and TTX-Resistant Sodium Channels in Aδ- and C-Fiber Conduction and Synaptic Transmission
Authors: Pinto Vitor , Derkach Victor A. , Safronov Boris V.
Published: December 2007

Thin afferent axons conduct nociceptive signals from the periphery to the spinal cord. Their somata express two classes of Na+channels, TTX-sensitive (TTX-S) and TTX-resistant (TTX-R), but their relative contribution to axonal conduction and synaptic transmission is not well understood. We studied this contribution by comparing effects of nanomolar TTX concentrations on currents associated with compound action potentials in the peripheral and central branches of Aδ- and C-fiber axons as well as on the Aδ- and C-fiber-mediated excitatory postsynaptic currents (EPSCs) in spinal dorsal horn neurons of rat. At room temperature, TTX completely blocked Aδ-fibers (IC50, 5–7 nM) in dorsal roots (central branch) and spinal, sciatic, and sural nerves (peripheral branch). The C-fiber responses were blocked by 85–89% in the peripheral branch and by 65–66% in dorsal roots (IC50, 14–33 nM) with simultaneous threefold reduction in their conduction velocity. At physiological temperature, the degree of TTX block in dorsal roots increased to 93%. The Aδ- and C-fiber-mediated EPSCs in dorsal horn neurons were also sensitive to TTX. At room temperature, 30 nM blocked completely Aδ-input and 84% of the C-fiber input, which was completely suppressed at 300 nM TTX. We conclude that in mammals, the TTX-S Na+channels dominate conduction in all thin primary afferents. It is the only type of functional Na+channel in Aδ-fibers. In C-fibers, the TTX-S Na+channels determine the physiological conduction velocity and control synaptic transmission. TTX-R Na+channels could not provide propagation of full-amplitude spikes able to trigger synaptic release in the spinal cord.
Endocannabinoids in TNF-α and Ethanol Actions
Authors: Rettori Valeria , Fernandez-Solari Javier , Prestifilippo Juan P. , Mohn Claudia , De Laurentiis Andrea , Bornstein Stefan R. , Ehrhart-Bornstein Monika , Elverdin Juan C. , McCann Samuel M.
Published: December 2007

During marijuana and alcohol consumption as well as during inflammation the reproductive axis is inhibited, mainly through the inhibition of luteinizing hormone-releasing hormone release. In male rats, this inhibitory effect is mediated, at least in part, by the activation of hypothalamic cannabinoid type 1 receptors (CB1). During inflammation, this activation of the endocannabinoid system seems to be mediated by an increase in TNF-α production followed by anandamide augmentations, similarly the effect of intragastric administration of ethanol (3 g/kg) seems to be due to an increase in anandamide. On the other hand, a number of different actions mediated by the endocannabinoid system in various organs and tissues have been described. Both cannabinoid receptors, CB1 and CB2, are localized in the submandibular gland where they mediate the inhibitory effect of intrasubmandibular injections of the endocannabinoid anandamide (6 × 10–5M) on salivary secretion. Lipopolysaccharide (5 mg/kg/3 h) injected intraperitoneally and ethanol (3 g/kg/1 h) injected intragastrically inhibited the salivary secretion induced by the sialogogue metacholine; this inhibitory effect was blocked by CB1 and/or CB2 receptor antagonists. Similar to the hypothalamus, these effects seem to be mediated by increased anandamide. In summary, similar mechanisms mediate the inhibitory actions of endocannabinoids and cannabinoids in both hypothalamus and submandibular gland during drug consumption and inflammation.
Diagnosis and Management of Hyperinsulinaemic Hypoglycaemia of Infancy
Authors: Hussain Khalid
Published: December 2007

Hyperinsulinaemic hypoglycaemia is a cause of persistent hypoglycaemia in the neonatal and infancy periods. Prompt recognition and management of patients with hyperinsulinaemic hypoglycaemia are essential, if brain damage and long-term neurological sequelae are to be avoided. Hyperinsulinaemic hypoglycaemia can be transient, prolonged, or persistent (congenital). Advances in the fields of molecular biology, genetics, and pancreatic β-cell physiology are beginning to provide novel insights into the mechanisms causing congenital forms of hyperinsulinism. So far mutations in six different genes have been described that lead to unregulated insulin secretion. The histological differentiation of focal and diffuse congenital hyperinsulinism has radically changed the surgical approach to this disease. Until recently, highly invasive investigations were performed to localize the focal lesion, but recent experience with 18F-L-dopa positron emission tomography scanning suggests that this technique is highly sensitive for differentiating diffuse from focal disease as well as for accurately locating the focal lesion. Despite recent advances, the genetic basis of congenital hyperinsulinism is still unknown in about 50% of the patients, and the management of medically unresponsive diffuse disease remains a real challenge.
An Evaluation of the Thyrotrophin-Releasing Hormone Stimulation Test in Paediatric Clinical Practice
Authors: Crofton Patricia M. , Tepper Leonie A. , Kelnar Christopher J.H.
Published: December 2007

Aim: The aim of this retrospective study was to evaluate the clinical usefulness of the thyrotropin-releasing hormone (TRH) test in children with suspected hypothalamic or pituitary dysfunction. Methods: We reviewed the case notes of all patients in whom a TRH test had been performed over a 6-year period. Group 1 (n = 85, 34 males, aged 0.9–18.8 years) was the reference group with no evidence of hypothalamic, pituitary or thyroid dysfunction. Group 2 (n = 42, 24 males, 0.1–18.0 years) were being investigated for possible pituitary or hypothalamic insufficiency. Results: In Group 1, thyrotropin (TSH) responses were higher in females than males (p < 0.01). In Group 2, TSH responses were normal for gender in 26 patients, subnormal in 5, and exaggerated/delayed in 11. Four patients with normal TSH responses and 4 with exaggerated/delayed responses had persistently low free thyroxine (FT4) or later developed low FT4 and were treated with thyroxine. All those with subnormal TSH responses had normal FT4 and were not treated. The TRH test did not reliably discriminate between hypothalamic and pituitary disorders. Conclusions: The TRH test did not give useful clinical information. Clinical decisions regarding thyroxine treatment were based on FT4, not the TRH test. The TRH test should be abandoned in paediatric practice.
Familial Glucocorticoid Deficiency: Advances in the Molecular Understanding of ACTH Action
Authors: Chan L.F. , Clark A.J.L. , Metherell L.A.
Published: December 2007

Familial glucocorticoid deficiency (FGD), otherwise known as hereditary unresponsiveness to ACTH, is a rare autosomal recessive disease characterized by glucocorticoid deficiency in the absence of mineralocorticoid deficiency. Mutations of the ACTH receptor, also known as the melanocortin-2 receptor (MC2R), account for approximately 25% of FGD cases. More recently a second gene, MRAP (melanocortin-2 receptor accessory protein), was identified and found to account for a further 15–20%. MRAP encodes a small single transmembrane domain protein, which is essential in the trafficking of the MC2R to the cell surface. In this review, we will firstly summarize the clinical presentation and genetic aetiology of this condition. Secondly, we will discuss how the discovery of MRAP has enhanced our understanding of the mechanisms of ACTH/MC2R action. Finally, we will explore future developments in this field.
Role of Fasting Plasma Glucose, Glycated Haemoglobin and Homeostatic Model Assessment in the Detection of Glucose Intolerance in Adult Hypopituitary Patients during Growth Hormone Replacement Therapy
Authors: Colson A. , Walker D. , Besser G.M. , Grossman A.B. , Chew S.L. , Jenkins P.J. , Drake W.M. , Monson J.P.
Published: December 2007

Aims: This study was designed to determine the sensitivity and specificity of conventional criteria for diagnosis of impaired glucose tolerance (IGT) in a high-risk population of GH-treated GH deficient (GHD) adults. Methods: 33 hypopituitary GHD patients with HbA1c >5.1% and 13 gender- and age-matched control GHD patients were selected. Oral glucose tolerance test (OGTT), fasting plasma glucose (FPG), HbA1c, and homeostatic model assessment (HOMA) parameters were determined in all patients. Receiver operator characteristic curves were used to determined sensitivity and specificity for the detection of glucose intolerance as defined by plasma glucose >7.8 mmol/l at 120 min during OGTT. Results: Sensitivity and specificity for this purpose for HbA1c (>5.1%) were 89 and 17%; for FPG (>5.5 mmol/l): 78 and 67%; for FPG (>6.1 mmol/l): 56 and 89%; for HOMA-derived β-cell function (βCF) (<40%): 78 and 58%; for HOMA-derived insulin sensitivity (IS) (<70%): 11 and 89%, and for βCF-IS hyperbolic product (βCF-IS) (<54%): 89 and 75%, respectively. Conclusions: This study shows that FPG (>5.5 mmol/l) and βCF-IS have high sensitivity and relatively high specificity for the detection of IGT and confirms that measurement of FPG or calculation of βCF-IS provides appropriate safety surveillance in hypopituitary patients on GH replacement.
Novel SHOX Gene Mutation in a Short Boy with Becker Muscular Dystrophy: Double Trouble in Two Adjacent Genes
Authors: Messina M.F. , Aguennouz M. , Arrigo T. , Rodolico C. , Valenzise M. , Musumeci O. , Vita G. , Lanzano N. , De Luca F.
Published: December 2007

Short stature is a well-recognized feature of Duchenne muscular dystrophy, whilst it has been reported rarely in Becker muscular dystrophy (BMD). Here we report two brothers with BMD, who exhibited a very different growth pattern. Whereas in the short brother (–2.2 SDS) molecular investigation revealed a G367A mutation in the short stature homeobox containing (SHOX) gene located in the Xp22.3 region, no abnormality was found in the brother with normal height (–0.1 SDS). Our data suggest that abnormal growth observed in a boy with BMD may be related to an additional genetic alteration, already known as correlated with short stature.
Risk of Fractures after Stroke
Authors: Brown Devin L. , Morgenstern Lewis B. , Majersik Jennifer J. , Kleerekoper Michael , Lisabeth Lynda D.
Published: December 2007

Background: The aim of this study was to determine the risk of fractures after stroke/transient ischemic attack (TIA) in relatively young patients. Methods: Administrative claims data were identified for patients aged 18 years and older hospitalized for stroke/TIA from 1997 to 2005 using ICD-9 codes. Fractures after stroke/TIA were identified for the same time period. Results: The median age was 56 years. Females represented 47%. There were 411 ischemic strokes, 195 TIAs and 36 intracerebral hemorrhages, as well as 46 fractures in 41 individuals. The risk of fracture after stroke/TIA was 1.2% at 30 days and 3.1% at 1 year. There was no significant difference in survival free from fracture between ischemic stroke and TIA cases (p = 0.8489). Conclusions: Patients with stroke/TIA, including men and younger patients, appear to be at risk for bone fractures.
Depression Subtypes in Bipolar I and II Disorders
Authors: Brugue E. , Colom F. , Sanchez-Moreno J. , Cruz N. , Vieta E.
Published: December 2007

Background: Depression is the predominant mood alteration in bipolar I and II disorders. In this study, the nature of major depressive episodes of bipolar I versus bipolar II patients is specifically assessed, as regards lifetime history of rapid cycling, melancholia, atypical and psychotic symptoms. Methods: The patient sample consisted of 184 bipolar I and 80 bipolar II patients, according to the research diagnostic criteria, who entered the bipolar disorders program in our hospital. Subsets of patients are compared according to DSM-IV criteria for rapid cycling, melancholic, atypical and psychotic features. Results: Bipolar I patients had significantly more psychotic symptoms in their lifetime histories (p < 0.001), whereas bipolar II patients had significantly more atypical symptoms in their lifetime histories (p < 0.003). Although melancholia was more prevalent in the bipolar I and rapid cycling was more prevalent in the bipolar II subgroup, these differences did not reach statistical significance. Conclusions: The results of the study suggest that marked differences exist in the nature of major depressive episodes between bipolar I and II patients, as they in the long term emerge from the two conditions. To what extent both conditions are related cannot be ascertained in the present study. Clinical differences may have relevant therapeutic implications and separate trials for bipolar I and bipolar II depression are warranted.
Francisco de Vitoria on just war on both sides and on the legal position of Burgundy
Authors: Winkel Laurens
Published: December 2007

Two texts of Francisco de Vitoria, a 16th century theologian, on the emerging concept of just war on both sides give interesting information on a less known aspect of the contemporary controversy between the Emperor Charles V and the French King François I: the position of the Duchy of Burgundy. These texts also link elegantly the theory of international law and political reality.
What Factors Are Important for Pediatric Residents' Smoking Cessation Counseling of Parents?
Authors: Dodge Rachel Anne Barnes , Cabana Michael D. , O'Riordan Mary Ann , Heneghan Amy
Published: December 2007

Pediatricians are expected to discuss the hazards of passive smoking and provide smoking cessation counseling (SCC) because passive smoking is known to have a direct negative effect on children's health. We conducted a cross-sectional survey of pediatric and medicine— pediatric residents at 2 training programs to identify resident-reported factors associated with higher confidence in and frequency of SCC. In this sample of 71 residents, 83% reported asking about parental smoking but only 36% reported counseling parents to quit smoking. Knowledge of smoking cessation resources was the factor most strongly associated with high confidence in and frequency of SCC. Research should be done to evaluate if improving awareness of smoking cessation resources for parents improves pediatricians' confidence in asking about parental smoking and the likelihood of advising parents to quit smoking.
How Should Immunization Rates Be Measured in the Office Setting? A Study from PROS and NMA PedsNet
Authors: Darden Paul M. , Taylor James A. , Brooks Dennis A. , Hendricks J.W. , Massoudi Mehran , Stevenson John M. , Bocian Alison B.
Published: December 2007

The aim of the study was to compare the validity and reliability of 2 sampling methods for measuring immunization rates to a reference standard in a national sample of pediatric office practices. The consecutive method involved patients seen consecutively in the office for any reason; the random record was a random selection of medical records; and the reference standard active method, data of a randomly selected subgroup of children in the random record survey were supplemented with information from a telephone interview. The consecutive method of assessing immunization rates results in rates that are, on average, higher and closer to the reference standard, but also more variable. The random record method rates are lower and further from the study reference standard compared with the consecutive method, but more precise. The consecutive method for measuring practice immunization rates could be a useful quality improvement tool as practices seek to improve immunization delivery and quality of care. It is inexpensive, simple, and easy to implement.
Diagnosis and Management of Common Dermatoses in Children: Atopic, Seborrheic, and Contact Dermatitis
Authors: Fleischer Alan B.
Published: December 2007

Atopic, seborrheic, and contact dermatitis can significantly reduce the quality of life of patients and their families. Although differing in specific aspects of their epidemiology, etiology, and pathobiology, all 3 dermatoses are common in the pediatric population, and they share a common treatment approach. Although effective and widely used to manage exacerbations of pediatric dermatitis, the use of topical corticosteroid remains a concern for some physicians and parents because of its potential for systemic absorption and adverse events associated with prolonged use. Newer additions to the dermatitis treatment algorithm, such as the topical calcineurin inhibitors, may provide an effective steroid-sparing treatment option. Adjuvant treatments, such as antihistamines, antifungals, and antibiotics, also can provide benefit in appropriate circumstances. As there is no cure for dermatitis, a comprehensive, multipronged management strategy of preventive measures, such as trigger avoidance and periodic pharmacologic treatment, will provide patients and caregivers with the best opportunity to successfully control the disease.
Neonatal Hyperbilirubinemia: An Unexpected Cause
Authors: Paulose Nidhy S. , Hart David , Rauch Daniel
Published: December 2007

Hyperbilirubinemia is a common cause for newborn hospital admission. Although the cause of hyperbilirubinemia is usually benign and self-limited, there is always a large differential diagnosis. Atypical presenting signs and symptoms, such as significant anemia or bleeding, should encourage further evaluation for underlying disorders, such as inherited coagulation defects. This article describes the case of a 5-day-old infant who presented to the emergency department with hyperbilirubinemia, anemia, and ecchymoses from birth trauma. His hospital course is described, along with a review on the background, evaluation, management, and complications of hemophilia A.
Cross-Cultural Learning Approaches in Students from the USA, Japan and Taiwan
Authors: Brown Michael B. , Aoshima Megumi , Bolen Larry M. , Chia Rosina , Kohyama Takaya
Published: December 2007

The purpose of this study is to examine the relationship between approaches to learning and locus of control of students from the USA, Japan, and Taiwan. The results show that students from the USA utilized more rote memory learning compared to students from Japan and Taiwan, while students from Japan were more likely to be `Achieving' learners than peers from either the USA or Taiwan. `Deep Approaches' to learning, however, were similar across the three groups. Students from both Japan and Taiwan exhibited higher levels of external orientation than did students from the USA. Although cultural characteristics were reflected in students' locus of control orientation, there were no differences in students' deep processing understanding strategies as all students displayed low levels. School psychologists must therefore be aware that students from different Asian cultural backgrounds do not have a singular approach to learning or a singular locus of control orientation. The mediating role of cultural context in learning must be considered for individual students in order to implement appropriate and effective teaching strategies, techniques, and methods that promote deep level understanding for learners with differing cultural backgrounds.
A Second-Order Simulation Model of the Cost-Effectiveness of Managing Dyspepsia in the United States
Authors: Barton Pelham M. , Moayyedi Paul , Talley Nicholas J. , Vakil Nimish B. , Delaney Brendan C.
Published: December 2007

Background. The ``gold-standard'' evidence of effectiveness for a clinical practice guideline is the randomized controlled trial (RCT), although RCTs have a limited ability to explore potential management strategies for a chronic disease where these interact over time. Modeling can be used to fill this gap, and models have become increasingly complex, with both dynamic sampling and representation of second-order uncertainty to provide more precise estimates. However, both simulation modeling and probabilistic sensitivity analysis are rarely used together. The objective of this study was to explore uncertainty in controversial areas of the 2005 American Gastroenterology Association position statement on the management of dyspepsia. Methods. Individual sampling model, incorporating a second-order probabilistic sensitivity analysis. Population. US adult patients presenting in primary care with dyspepsia. Interventions compared: empirical acid suppression, test and treat for Helicobacter pylori, initial endoscopy, acid suppression then endoscopy, test and treat then proton pump inhibitor (PPI) then endoscopy. Outcomes. Cost-effectiveness, quality-adjusted life years, and costs in US dollars from a societal perspective, measured over a 5-year period. Data sources: mainly Cochrane meta-analyses. Results. Endoscopy was dominated at all ages by other strategies. PPI therapy was the most cost-effective strategy in 30-year-olds with a low prevalence of H. pylori. In 60-year-olds, H. pylori test and treat was the most cost-effective option. Conclusions. Acid suppression alone was more cost-effective than either endoscopy or H. pylori test and treat in younger dyspepsia patients with a low prevalence of infection.
Physician-Patient Discussions With African American Men About Prostate Cancer Screening
Authors: Ross Louie E. , Powe Barbara D. , Taylor Yhenneko J. , Howard Daniel L.
Published: December 2007

Prostate cancer is the second leading cancer killer in men. Men in general and African American men in particular face crucial decisions regarding prostate cancer screening and perhaps treatment for this disease. Major health organizations agree that men should discuss prostate cancer screening with their physicians or other health care professionals. The purpose of the study was to examine sociodemographic and other correlates of physician-patient discussions regarding the advantages and disadvantages of the prostate-specific antigen (PSA) test among African American men aged 40 or older. A majority of African American men reported having discussed the advantages and disadvantages of prostate cancer screening and/or testing with their physicians before ordering it, and physician-patient discussions about the PSA test were associated with increased screening in African American men. Inasmuch as African American men have greater prostate cancer incidence and mortality over other groups, future attempts should be made to find meaningful correlates of PSA screening and test use to help reduce the burden of this disease.
Smoking cessation treatment in a real-life setting: the Greek experience
Authors: Rovina Nikoletta , Nikoloutsou Ioanna , Dima Efi , Michailidou Makrina , Roussos Charalampos , Gratziou Christina
Published: December 2007

Objectives: The aim of this study was to estimate the clinical efficacy of counseling combined with currently used pharmacotherapy for smoking cessation (bupropion SR and nicotine replacement therapy, NRT) in actual clinical practice, and to identify predictors of successful abstinence at the end of therapy, as well as predictors of sustained abstinence in one year.

Methods: 895 smokers, self—motivated to quit, received bupropion SR for 7 or 19 weeks and/or nicotine replacement therapy (NRT) (nicotine patch) for 9 weeks in combination with individual behavioural therapy. An intensive program including repetitive visits and telephone contacts during treatment and one year's follow-up period was available for supporting and motivating smokers to prevent relapse.

Results: Post-treatment abstinence rates were 71.6% and 53.2% in bupropion SR groups for 7 and 19 weeks of treatment, respectively, ( p < 0 .001), 63.4% in bupropion SR plus nicotine patch group and 45% ( p < 0 .001) in nicotine patch group. One year's follow-up abstinence rates were 43.1%, 29.6%, 30.4% and 18.4% ( p < 0 .05), respectively. Predictors of successful abstinence at the end of therapy included (a) bupropion SR, (b) lower DSM IV symptom score, and (c) lower nicotine addiction, while predictors for sustained abstinence in one year included: (a) bupropion SR, (b) lower nicotine addiction, and (c) smoker's motivation.

Conclusions: Smoking cessation interventions implementing intensive multi-component programs and constant smokers' motivation in health care settings of actual practice seem promising for increasing short and long-term abstinence rates.
Review: The potential role of natural agents in treatment of airway inflammation
Authors: Sharafkhaneh Amir , Velamuri Suryakanta , Badmaev Vladimir , Lan Charlie , Hanania Nicola
Published: December 2007

Obstructive airway diseases including asthma, chronic obstructive pulmonary disease and cystic fibrosis present with dyspnea and variety of other symptoms. Physiologically, they are characterized by maximal expiratory flow limitation and pathologically, by inflammation of the airways and the lung parenchyma. Inflammation plays a major role in the gradual worsening of the lung function resulting in worsening symptoms. For many years, scientists focused their efforts in identifying various pathways involved in the chronic inflammation present in these diseases. Further, studies are underway to identify various molecular targets in these pathways for the purpose of developing novel therapeutic agents. Natural agents have been used for thousands of years in various cultures for the treatment of several medical conditions and have mostly proven to be safe. Recent in vivo and in vitro studies show potential anti-inflammatory role for some of the existing natural agents. This review provides an overview of the literature related to the anti-inflammatory effects of some of the natural agents which have potential value in the treatment of inflammatory lung diseases.
Phenotypic characterisation of T-lymphocytes in COPD: abnormal CD4+CD25+ regulatory T-lymphocyte response to tobacco smoking
Authors: Barceló B. , Pons J. , Ferrer J. M. , Sauleda J. , Fuster A. , Agustí A. G. N.
Published: December 2007

Tobacco smoking induces an inflammatory response in the lungs of all smokers but, for reasons that are still poorly understood, only a proportion of them develop chronic obstructive pulmonary disease (COPD). Recent evidence indicates that this inflammatory response persists after smoking cessation, suggesting some type of auto-perpetuation mechanism similar to that described in autoimmune disorders. T-lymphocytes (CD4+ and CD8+) have been implicated in the pathogenesis of both COPD and several autoimmune processes. A subtype of regulatory CD4+ T-cells expressing CD25 (Tregs) plays a critical role in the maintenance of peripheral tolerance and the prevention of autoimmunity, but their potential role in COPD has not been explored. The present study sought to evaluate maturation (CD45RA/CD45R0) and activation markers (CD28) of T-lymphocytes and to explore potential Treg abnormalities in COPD.

Flow cytometry was used to characterise T-lymphocytes obtained from blood and bronchoalveolar lavage fluid (BALF) in 23 patients with moderate COPD, 29 smokers with normal lung function and seven never-smokers.

The main findings were that in BALF: patients with COPD showed higher CD8+CD45RA+ and lower CD8+CD45R0+ than smokers with normal lung function; and compared with never-smokers, smokers with preserved lung function showed a prominent upregulation of Tregs that was absent in patients with COPD.

These observations indicate a final maturation-activation state of CD8+ T-lymphocytes in chronic obstructive pulmonary disease and, for the first time, identify a blunted regulatory T-cell response to tobacco smoking in these patients, further supporting a potential involvement of the acquired immune response in the pathogenesis of the disease.
Fibrinogen Aα Thr312Ala polymorphism is associated with chronic thromboembolic pulmonary hypertension
Authors: Suntharalingam J. , Goldsmith K. , van Marion V. , Long L. , Treacy C. M. , Dudbridge F. , Toshner M. R. , Pepke-Zaba J. , Eikenboom J. C. J. , Morrell N. W.
Published: December 2007

Although chronic thromboembolic pulmonary hypertension (CTEPH) is characterised by the persistence of organised thrombus, few pro-thrombotic risk factors have been identified in subjects with the disease. The aim of the present study was to compare the prevalence of eight functionally relevant haemostatic polymorphisms between CTEPH subjects and healthy controls.

Genomic DNA was isolated from 214 CTEPH subjects and 200 healthy controls, and analysed for Factor V Leiden, prothrombin guanine (G) to adenine (A) substitution at nucleotide 20210 (20210G>A), plasminogen activator inhibitor-1 4G/5G, tissue plasminogen activator 7351 cytosine (C)>thymidine (T), Factor XIII 100G>T, fibrinogen Aα substitution of threonine with alanine at position 312 (Thr312Ala), fibrinogen Bβ substitution of arginine with lysine at position 448 (Arg448Lys) and fibrinogen Bβ 455G>A polymorphisms.

A significant difference was demonstrated in fibrinogen Aα Thr312Ala genotype and allele frequencies between CTEPH subjects and controls. The presence of the alanine allele significantly increased the risk of CTEPH.

The fibrinogen Aα alanine 312 allele alters fibrinogen α–α chain cross-linkage and has previously been associated with both increased risk of embolisation and increased resistance to thrombolysis. An association between this polymorphism and chronic thromboembolic pulmonary hypertension, therefore, supports an embolic aetiology for this disease, and may provide a mechanism by which thrombus persists following an acute event.
Endurance shuttle walking test: responsiveness to salmeterol in COPD
Authors: Brouillard C. , Pepin V. , Milot J. , Lacasse Y. , Maltais F.
Published: December 2007

Few studies have shown that the endurance shuttle walking test (ESWT) is responsive to treatment in patients with chronic obstructive pulmonary disease (COPD). This exercise test needs to be further investigated because of its relevance for activity of daily living. The aim of the present study was to evaluate, in patients with COPD, the responsiveness of the ESWT in detecting improvement in walking performance after a single dose of salmeterol.

In a randomised, double-blind, placebo-controlled crossover trial, 20 patients with COPD performed two ESWT at 80% of peak capacity 2.5 h after inhaling either a placebo or 50 µg of salmeterol. Cardiorespiratory parameters were monitored during each walking test. Inspiratory capacities and Borg ratings for dyspnoea were obtained every other minute throughout the tests.

Compared with placebo, salmeterol produced a significant change in lung function and a significant improvement in walking performance (mean±sddifference in time: 117±20 s; difference in distance: 160±277 m). At isotime (the latest exercise time that was reached on both ESWT), a significant reduction in dyspnoea was observed after bronchodilation.

Bronchodilation with salmeterol reduced dyspnoea during walking and improved walking capacity in patients with chronic obstructive pulmonary disease. These findings provide further support for the use of the endurance shuttle walking test as an evaluative tool in chronic obstructive pulmonary disease.
Inhibition of VEGF blocks TGF-β1production through a PI3K/Akt signalling pathway
Authors: Lee K. S. , Park S. J. , Kim S. R. , Min K. H. , Lee K. Y. , Choe Y. H. , Hong S. H. , Lee Y. R. , Kim J. S. , Hong S. J. , Lee Y. C.
Published: December 2007

Vascular endothelial growth factor (VEGF) is a mediator of airway inflammation and remodelling in asthma. Transforming growth factor (TGF)-β1plays pivotal roles in diverse biological processes, including tissue remodelling and repair in a number of chronic lung diseases. However, there are few studies elucidating the interactions between VEGF and TGF-β1in allergic airway disease.

A murine model of allergic airway disease was used to define the mechanism by which VEGF induces subepithelial fibrosis and to investigate a potential relationship between VEGF and TGF-β1and the mechanisms by which VEGF signalling regulates TGF-β1expression in allergic airway disease.

The ovalbumin (OVA)-inhaled murine model revealed the following typical pathophysiological features of allergic airway disease in the lungs: increased numbers of inflammatory cells of the airways, airway hyperresponsiveness, increased peribronchial fibrosis, and increased levels of VEGF and TGF-β1. Administration of VEGF inhibitors reduced the pathophysiological signs of allergic airway disease and decreased the increased TGF-β1levels and peribronchial fibrosis, including phosphoinositide 3-kinase (PI3K) activity after OVA inhalation. In addition, the increased TGF-β1levels and collagen deposition after OVA inhalation were decreased by administration of PI3K inhibitors.

These results suggest that inhibition of vascular endothelial growth factor attenuates peribronchial fibrosis, at least when mediated by regulation of transforming growth factor-β1expression through phosphoinositide 3-kinase/Akt pathway in a murine model of allergic airway disease.