bluuebunny/crossref_metadata_2025 huggingface dataset:
Mitochondrial DNA phylogeny of two morphologically enigmatic fishes in the subfamily Schizothoracinae (Teleostei: Cyprinidae) in the Qinghai‐Tibetan Plateau
Authors: Qi D. , Guo S. , Tang J. , Zhao X. , Liu J.
Published: February 2007

The complete mitochondrial DNA (mtDNA) cytochrome b gene (1140 bp) was sequenced in Herzenstein macrocephalus and Gymnocypris namensis and in 13 other species and sub‐species (n= 22), representing four closely related genera in the subfamily Schizothoracinae. Conflicting taxonomies of H. macrocephalus and G. namensis have been proposed because of the character instability among individuals. Parsimony, maximum likelihood and Bayesian methods produced phylogenetic trees with the same topology and resolved several distinctive clades. Previous taxonomic treatments, which variously placed these two species of separate genera or as sub‐species, are inconsistent with the mtDNA phylogeny. Both H. macrocephalus and G. namensis appear in a well‐supported clade, which also includes nine species of Schizopygopsis, and hence should be transferred to the genus Schizopygopsis. Morphological changes are further illustrated, and their adaptive evolution in response to the local habitat shifts during the speciation process appears to be responsible for conflicting views on the systematics of these two species and hence the contrasting taxonomic treatments. These species are endemic to the Qinghai‐Tibetan Plateau, a region with a history of geological activity and a rich diversity of habitats that may have result in the parallel and reversal evolution of some morphological characters used in their taxonomies. Our results further suggest that speciation and morphological evolution of fishes in this region may be more complex than those previously expected.
Learners' evaluation of a navigation support tool in distance education
Authors: Bolman C. , Tattersall C. , Waterink W. , Janssen J. , Van Den Berg B. , Van Es R. , Koper R.
Published: February 2007

Abstract  This article investigates the usability of a navigation support tool, which guides learners by generating advice on the next best step to take in a self‐study e‐learning course. The article draws on log data and responses from online questionnaires to provide insights into learners' evaluation of the tool, their adherence to the advice and their expectations of self‐efficacy. The theoretical underpinnings of the work are described together with the experimental set‐up. Results show that more than half of the learners in the experimental group adhered to the advice and held the opinion that the advice stimulated them to proceed with the course. Learners expressed a need to know what the advice was based on which can be seen as an essential element in future development of the tool.
STAGGERED PRICE CONTRACTS AND INFLATION PERSISTENCE: SOME GENERAL RESULTS*
Authors: Whelan Karl
Published: February 2007

Despite their popularity as theoretical tools for illustrating the effects of nominal rigidities, some have questioned whether models based on staggered price contracts with rational expectations can match the persistence of the empirical inflation process. This article presents some general results about this class of models. It is shown that these models do not have a problem matching high autocorrelations for inflation. However, they fail to explain a key feature of reduced‐form Phillips‐curve regressions: The positive dependence of inflation on its own lags. It is shown that staggered price contracting models instead predict that the coefficients on these lag terms should be negative.
COSTLY INTERMEDIATION AND THE POVERTY OF NATIONS*
Authors: Chakraborty Shankha , Lahiri Amartya
Published: February 2007

This article has two goals: (i) to reduce the 7‐fold productivity differential required to explain the observed 33‐fold income difference between the richest and poorest countries of the world; and (ii) to explain cross‐country differences in the capital‐output ratio. To achieve the first goal we modify the production function of the standard neoclassical growth model to include public capital whose provision is subject to intermediation costs. For the second goal we distort private investment by introducing credit frictions. The model, quantified using cross‐country data, generates an income gap of 33 with productivity differences of only 3 under the measured variations in public and private capital. The required productivity gap declines even further, to 2.1, when we introduce a home‐production sector. On the second goal, however, credit frictions do a poor job of explaining cross‐country variations in the capital‐output ratio.
UNEMPLOYMENT AND HOURS OF WORK: THE NORTH ATLANTIC DIVIDE REVISITED*
Authors: Pissarides Christopher A.
Published: February 2007

I examine the dynamic evolutions of unemployment, hours of work, and the service share since the war in the United States and Europe. The theoretical model brings together all three and emphasizes technological growth. Computations show that the very low unemployment in Europe in the 1960s was due to the high productivity growth associated with technological catch‐up. Productivity also played a role in the dynamics of hours, but a full explanation for the fast rise of service employment and the big fall in aggregate hours needs further research. Taxation has played a role but results are mixed.
Efficacy of Eletriptan in Triptan‐Naïve Patients: Results of a Combined Analysis
Authors: Martin Vincent T. , Valade Dominique , Almas Mary , Hettiarachchi Jayasena , Sikes Carolyn , Albert Kenneth S. , Parsons Bruce
Published: February 2007

Objective.—To compare the efficacy and tolerability of eletriptan 20 mg, 40 mg, and 80 mg in triptan‐naïve patients (who have not previously used triptans) versus triptan‐experienced patients (who have previously used triptans).

Methods.—Efficacy and tolerability data for eletriptan 20 mg, 40 mg, and 80 mg were pooled from 10 similarly designed, randomized, parallel‐group studies, and triptan‐naïve and triptan‐experienced patients were compared with placebo across the 3 triptan doses. The primary efficacy endpoint was headache response at 2 hours postdose. Secondary efficacy endpoints were 2‐hour pain‐free response, 2‐hour absence of associated symptoms, 2‐hour functional response, 24‐hour sustained headache response, and 24‐hour sustained pain‐free response.

Results.—For eletriptan 20 mg, 40 mg, and 80 mg versus placebo, respectively, triptan‐naïve patients showed significantly higher 2‐hour headache response (54%, 61%, 66% vs. 31%; P < .0001), 2‐hour pain‐free response (20%, 28%, and 31% vs. 8%; P < .0001), and 24‐hour sustained headache response (34%, 45%, and 51% vs. 20%; P < .0001). A similarly significant efficacy advantage was also observed in the triptan‐experienced subgroup for 2‐hour headache response (46%, 63%, 69% vs. 21%; P < .0001), 2‐hour pain‐free response (13%, 32%, and 38% vs. 4%; P < .0001), and 24‐hour sustained headache response (29%, 41%, and 45% vs. 9%; P < .0001). Previous treatment status did not influence tolerability, and all 3 doses of eletriptan were well tolerated.

Conclusions.—These data suggest that eletriptan has comparable efficacy versus placebo among both triptan‐naïve and triptan‐experienced patients.
Clarification of Developing and Established Clinical Allodynia and Pain‐Free Outcomes
Authors: Landy Stephen H. , McGinnis Judy E. , McDonald Susan A.
Published: February 2007

Objective.—The aim of this study was to determine whether clinical indicators of cutaneous allodynia predict the success of migraine therapy with sumatriptan using a brief questionnaire.

Background.—Using quantitative sensory testing (QST) recent studies demonstrate that the presence of cutaneous allodynia, a clinical manifestation of central sensitization, can be detrimental to the success of migraine therapy with sumatriptan. QST is costly and requires much time, therefore it is not feasible to use in clinical practice.

Methods.—In this prospective study, migraineurs completed a questionnaire about their skin sensitivity during migraine. Each migraineur treated 2 migraine headaches with sumatriptan (100 mg): 1 headache at the earliest sign of migraine pain (mild, within 1 hour of onset) and 1 headache at least 4 hours after the onset of pain while moderate or severe.

Results.—Thirty‐six migraine headaches were evaluated in 18 migraineurs. A total of 44% of the headaches were not associated with allodynia at any time. Irrespective of allodynic status, headaches were more likely to become pain‐free with early versus late treatment (2 hours; 78% vs. 33%, respectively). Headaches were equally likely to become pain‐free when allodynia was reported before treatment but not 2 and 4 hours after treatment (2 hours; 67 vs. 63%, respectively, 4 hours 80 vs. 81%, respectively). However, no headaches were pain‐free when allodynia was reported at 2 and 4 hours after treatment.

Conclusions.—Headaches without allodynia were aborted when treated early or late, and headaches with allodynia were aborted only when allodynia was not present after treatment. These findings suggest that different mechanisms account for allodynia before and after treatment; a developing phase in which central sensitization depends on incoming pain signals from the peripheral nociceptors and an established phase in which the sensitization becomes independent of the pain signals that come from the dura.
A Migraine‐Like Headache Induced by Carotid‐Cavernous Fistula
Authors: Yamada Shoko M. , Masahira Noritaka , Shimizu Keiji
Published: February 2007

Carotid‐cavernous fistula (CCF) generally causes periorbital aching with ocular symptoms due to high venous pressure in the cavernous sinus, while migraine is caused by arterial dilatation‐stimulating trigeminal nerves around the vessels. The authors present a case of 47‐year‐old woman with a 4‐month history of a temporal throbbing headache. As her symptoms were well controlled by triptans, her headache was considered to be migraine in type. However, a Barrow's type‐D CCF was revealed by radiological examinations. Self‐compression of common carotid artery method was initially tried for therapy of the CCF, but endovascular embolization was finally necessary due to intractable headache. Although the headache was considered arterial in origin, transvenous embolization of the left cavernous sinus successfully ameliorated the patient's symptoms. CCF should be considered as an unusual etiology of headaches that appear arterial in origin.
Repeat Trigeminal Nerve Radiosurgery for Refractory Cluster Headache Fails to Provide Long‐Term Pain Relief
Authors: McClelland Shearwood , Barnett Gene H. , Neyman Gennady , Suh John H.
Published: February 2007

Objective/Background.—Medically refractory cluster headache (MRCH) is a debilitating condition that has proven resistant to many modalities. Previous reports have indicated that radiosurgery for MRCH provides little long‐term pain relief, with moderate/significant morbidity. However, there have been no reports of repeated radiosurgery in this patient population. We present our findings from the first reports of repeat radiosurgery for MRCH.

Methods.—Two patients with MRCH underwent repeat gamma knife radiosurgery at our institution. Each fulfilled clinical criteria for treatment, including complete resistance to pharmacotherapy, pain primarily localized to the ophthalmic division of the trigeminal nerve, and psychological stability. Both patients previously received gamma knife radiosurgery (75 Gy) for MRCH with no morbidity, but no long‐term improvement of pain relief (Patient 1 = 5 months, Patient 2 = 10 months) after treatment. For repeat radiosurgery, each patient received 75 Gy to the 100% isodose line delivered to the root entry zone of the trigeminal nerve, and was evaluated postretreatment. Pain relief was defined as: excellent (free of MRCH with minimal/no medications), good (50% reduction of MRCH severity/frequency with medications), fair (25% reduction), or poor (less than 25% reduction).

Results.—Following repeat radiosurgery, long‐term pain relief was poor in both patients. Neither patient sustained any immediate morbidity following radiosurgery. Patient 2 experienced right facial numbness 4 months postretreatment, while Patient 1 experienced no morbidity.

Conclusion.—Repeat radiosurgery of the trigeminal nerve fails to provide long‐term pain relief for MRCH. Given the reported failures of initial and repeat radiosurgery for MRCH, trigeminal nerve radiosurgery should not be offered for MRCH.
MRA Captures Vasospasm in Fatal Migrainous Infarction
Authors: Marshall Nina , Maclaurin William A. , Koulouris George
Published: February 2007

A 57‐year‐old woman presented with an escalation of her headaches which ultimately progressed to multiple strokes and death. MRI/MRA demonstrated diffuse vasospasm and other causes of stroke were excluded on premortem investigation and postmortem examination. Reversible MRI abnormalities, vasospasm on angiogram and fatal migrainous infarction have been previously reported; however, no previous case with this combination of clinical, imaging, and postmortem findings has been documented.
Autogenous bone graft alone or associated with titanium mesh for vertical alveolar ridge augmentation: a controlled clinical trial
Authors: Roccuzzo Mario , Ramieri Guglielmo , Bunino Marco , Berrone Sid
Published: February 2007

Objectives: The aim of this controlled clinical trial is to evaluate alveolar ridge augmentation using an autogenous onlay bone graft alone or associated with a titanium mesh (Ti‐Mesh).

Material and methods: A group of 23 partially edentulous patients, presenting the need for vertical bone augmentation of at least 4 mm, were treated before implant placement. Surgical procedure was performed by the same operator and was identical at 12 test (bone graft+Ti‐Mesh) and 12 control (bone graft alone) sites. During the first surgery, an autogenous bone graft was harvested from the mandibular ramus and secured by means of titanium screws. Particulate bone was added. In patients assigned to the test group only, a Ti‐Mesh was used to stabilize and protect the graft.

Results: No major complications were recorded at recipient or donor sites. After a mean interval of 4.6 (SD 0.7) months, the mean vertical augmentation obtained was 5 mm (range 4–7 mm) for the test group and 3.4 mm (range 3–6 mm) for the control. The sites with Ti‐Mesh coverage underwent bone resorption of 13.5%, while the sites with no coverage showed a corresponding value of 34.5%. The differences between the two groups were statistically significant. Implants were placed at all grafted sites.

Conclusion: The results of this study suggest that an onlay osseous graft protected by a Ti‐Mesh demonstrated significantly less bone resorption when compared with an onlay bone graft alone. This benefit was reduced in case of short‐term mesh exposure, with limited drawbacks.
Evaluation of tongue coating indices
Authors: Lundgren T , Mobilia A , Hallström H , Egelberg J
Published: February 2007

Aim:  The purpose of this study was to determine inter‐examiner reproducibility of two modified Winkel tongue coating indices and to study the relationship between each of these two indices and the amount of tongue coating as determined by wet weight of scrapings from the dorsum of the tongue.

Materials and methods:  Twenty‐five participants were selected for the study from among dental students. The selection was made to assure that a wide range of degrees of tongue coating were represented. Two independent examiners scored the tongue coatings using the two modified Winkel tongue coating indices (mWTCI 1 + 2 and mWTCI 2). After completion of index recordings, tongue scrapings were performed by one of the examiners.

Results:  Inter‐examiner reproducibility of mWTCI 1 + 2 and mWTCI 2 using Pearson's coefficients of correlation amounted to r = 0.48 and 0.93 respectively. Overall, mWTCI 2 showed higher correlations to wet weight of tongue scrapings than mWTCI 1 + 2.

Conclusion:  The mWTCI 2 was found to be highly reproducible and also valid as related to wet weight of tongue scrapings. This index would seem suitable for further studies on tongue coatings; effect of tongue cleaning; and rate of reformation of coatings after cleaning.
An MTT‐based method for quantification of periodontal ligament cell viability
Authors: Kim E , Jeon IS , Kim JW , Kim J , Jung H‐S , Lee SJ
Published: February 2007

Objective:  Survival of periodontal ligament cells is crucial issue after tooth replantation. To understand this matter, we introduced MTT assay, which can be used as a tool for measuring the viability of periodontal ligament cells from extracted rat molars.

Materials and methods:  The maxillary molars of 4‐week‐old Sprague–Dawley white female rats were used. Ten teeth of each immediate, 1 h Viaspan and 1 h dry were processed for MTT evaluation. Another 10 teeth from each group were treated in the same manner as above, but were replanted into their original socket. After 2 weeks, the animals were killed and the prevalence of resorption pits was evaluated.

Results:  In vivo MTT assay corresponded with the histological results of the resorption pits (P ≤ 0.05). The polarizing and optical microscopic findings were consistent with the in vivo MTT assay results.

Conclusions:  In vivo MTT measurements were consistent with the histologic observations and suggest that the in vivo MTT assay could be a tool for evaluating the viability of periodontal ligament cells directly from the extracted root surface. The advantages are shorter analysis time compared with animal or cell culture experiments, easy manipulation, clear quantification and immediate identification of the vital cells.
Trigeminal neuropathy
Authors: Peñarrocha M , Cervelló MA , Martí E , Bagán JV
Published: February 2007

Trigeminal neuropathies (TNs) are well recognized disorders characterized and manifesting as skin and mucosal numbness in the region innervated by the trigeminal nerve. Facial numbness indicates trigeminal sensory alteration affecting the trigeminal system. TNs always pose differential location difficulties as multiple diseases are capable of producing them: they can be the result of traumatism, tumors, or diseases of the connective tissue, infectious or demyelinating diseases, or may be of idiopathic origin. Their importance is explained by the fact that TN may represent the first manifestation of tumor disease, or of relapse in patients with prior neoplastic processes. As such, these manifestations are ominous, and patient life expectancy is often short. The clinical exploration reveals a loss of sensitivity in the cutaneous territory corresponding to the affected nerve, which can be partial (hypoesthesia) or complete (anesthesia). The sensory defect is occasionally associated with hyperesthesia (i.e., the patient suffers a decrease in sensory perception, but when sensation is perceived, it may cause considerable discomfort). Complementary studies are needed to establish the etiologic diagnosis, with laboratory tests to discard the possible causative diseases underlying the trigeminal neuropathy, and the opportune radiographic examinations in the form of plain X‐rays or a routine cranial computed tomography scan.
The use of point‐of‐care ultrasound by a critical care retrieval team to diagnose acute abdominal aortic aneurysm in the field
Authors: Mazur Stefan M , Sharley Peter
Published: February 2007

The potential benefit of point‐of‐care ultrasound by medical retrieval teams is unclear. In the present case report, the diagnosis of an abdominal aortic aneurysm by a critical care retrieval team equipped with a portable ultrasound machine resulted in significant corrective alteration in patient management and subsequent disposition at the receiving institution.
Paediatric intussusception: Epidemiology and outcome
Authors: Blanch Andrew JM , Perel Susan B , Acworth Jason P
Published: February 2007

Objectives:  (i) To describe the clinical presentation of intussusception and determine features associated with earlier diagnosis; (ii) to describe outcomes of children diagnosed with intussusception; and (iii) to determine whether time to diagnosis is associated with poorer prognosis.

Methods:  A retrospective review was performed of all patients presenting to a tertiary paediatric hospital with a diagnosis of intussusception during a 10 year study period.

Results:  One hundred and forty‐one confirmed cases met the inclusion criteria, giving an incidence of one case per 1450 ED presentations. The median age of presentation was 9 months, with a ratio of male to female of 2:1. Three or more of the four ‘classic’ features of intussusception (vomiting, abdominal pain, bloody/red currant jelly stool, or abdominal mass) were reported in only 46% of presentations. Median time to confirmation of diagnosis was 19 h from onset of symptoms. Ultrasound was the most commonly employed method used to confirm the diagnosis. Air enema had a success rate of 80%, with a reduced success rate beyond the first attempt. Early diagnosis was associated with decreased frequency of surgical intervention and need for bowel resection.

Conclusion:  The ‘classic’ picture of intussusception might frequently not be present in children with intussusception. Reliance on ‘classic’ features alone might delay diagnosis. Delayed diagnosis is associated with poorer patient outcomes. Air enema has a high success rate for reduction of intussusception.
Histopathological assessment of lymph nodes in upper gastrointestinal cancer: does triple levelling detect significantly more metastases?
Authors: McGrath Stephen , Cross Sarah , Pritchard Susan Anne
Published: February 2007

Background:

For cancers of the upper gastrointestinal tract it is standard to examine one section/level, from paraffin blocks containing lymph node tissue, for metastatic tumour.

Aims:

To determine whether significantly more metastases can be detected by assessing two additional levels.

Methods:

101 archival upper gastrointestinal cancers were evaluated. All negative lymph nodes were examined at two additional levels separated by 100 μm and stained by H&E. The slides were examined for the presence of metastases.

Results:

1143 lymph nodes, that were originally clear of metastases, were examined at a further two levels (three levels in total); 23 additional metastases were identified in 17 patients. Eleven of these patients were already stage N1 before examination of the additional levels. However, six patients were originally N0, and were therefore upgraded to N1.

Conclusions:

Examining lymph nodes at three levels did detect more metastatic deposits than examination of one section/level. In six patients this changed the N stage from N0 to N1. This would have significant prognostic and management implications.
Analysis of compensatory β-cell response in mice with combined mutations of Insr and Irs2
Authors: Kim Jane J. , Kido Yoshiaki , Scherer Philipp E. , White Morris F. , Accili Domenico
Published: February 2007

Type 2 diabetes results from impaired insulin action and β-cell dysfunction. There are at least two components to β-cell dysfunction: impaired insulin secretion and decreased β-cell mass. To analyze how these two variables contribute to the progressive deterioration of metabolic control seen in diabetes, we asked whether mice with impaired β-cell growth due to Irs2 ablation would be able to mount a compensatory response in the background of insulin resistance caused by Insr haploinsufficiency. As previously reported, ∼70% of mice with combined Insr and Irs2 mutations developed diabetes as a consequence of markedly decreased β-cell mass. In the initial phases of the disease, we observed a robust increase in circulating insulin levels, even as β-cell mass gradually declined, indicating that replication-defective β-cells compensate for insulin resistance by increasing insulin secretion. These data provide further evidence for a heterogeneous β-cell response to insulin resistance, in which compensation can be temporarily achieved by increasing function when mass is limited. The eventual failure of compensatory insulin secretion suggests that a comprehensive treatment of β-cell dysfunction in type 2 diabetes should positively affect both aspects of β-cell physiology.
Effect of maternal triglycerides and free fatty acids on placental LPL in cultured primary trophoblast cells and in a case of maternal LPL deficiency
Authors: Magnusson-Olsson Anne Liese , Lager Susanne , Jacobsson Bo , Jansson Thomas , Powell Theresa L.
Published: February 2007

Maternal hypertriglyceridemia is a normal condition in late gestation and is an adaptation to ensure an adequate nutrient supply to the fetus. Placental lipoprotein lipase (LPL) is involved in the initial step in transplacental fatty acid transport as it hydrolyzes maternal triglycerides (TG) to release free fatty acids (FFA). We investigated LPL activity and protein (Western blot) and mRNA expression (real-time RT-PCR) in the placenta of an LPL-deficient mother with marked hypertriglyceridemia. The LPL activity was fourfold lower, LPL protein expression 50% lower, and mRNA expression threefold higher than that of normal, healthy placentas at term ( n = 4–7). To further investigate the role of maternal lipids in placental LPL regulation, we isolated placental cytotrophoblasts from term placentas and studied LPL activity and protein and mRNA expression after incubation in Intralipid (as a source of TG) and oleic, linoleic, and a combination of oleic, linoleic, and arachidonic acids as well as insulin. Intralipid (40 and 400 mg/dl) decreased LPL activity by ≈30% ( n = 10–14, P < 0.05) and 400 μM linoleic and linoleic-oleic-arachidonic acid ( n = 10) decreased LPL activity by 37 and 34%, respectively. No major changes were observed in LPL protein or mRNA expression. We found no effect of insulin on LPL activity or protein expression in the cultured trophoblasts. To conclude, the activity of placental LPL is reduced by high levels of maternal TG and/or FFA. This regulatory mechanism may serve to counteract an excessive delivery of FFA to the fetus in conditions where maternal TG levels are markedly increased.
Effects on insulin secretion and insulin action of a 48-h reduction of plasma free fatty acids with acipimox in nondiabetic subjects genetically predisposed to type 2 diabetes
Authors: Cusi Kenneth , Kashyap Sangeeta , Gastaldelli Amalia , Bajaj Mandeep , Cersosimo Eugenio
Published: February 2007

Elevated plasma FFA cause β-cell lipotoxicity and impair insulin secretion in nondiabetic subjects predisposed to type 2 diabetes mellitus [T2DM; i.e., with a strong family history of T2DM (FH+)] but not in nondiabetic subjects without a family history of T2DM. To determine whether lowering plasma FFA with acipimox, an antilipolytic nicotinic acid derivative, may enhance insulin secretion, nine FH+ volunteers were admitted twice and received in random order either acipimox or placebo (double-blind) for 48 h. Plasma glucose/insulin/C-peptide concentrations were measured from 0800 to 2400. On day 3, insulin secretion rates (ISRs) were assessed during a +125 mg/dl hyperglycemic clamp. Acipimox reduced 48-h plasma FFA by 36% ( P < 0.001) and increased the plasma C-peptide relative to the plasma glucose concentration or ΔC-peptide/Δglucose AUC (+177%, P = 0.02), an index of improved β-cell function. Acipimox improved insulin sensitivity (M/I) 26.1 ± 5% ( P < 0.04). First- (+19 ± 6%, P = 0.1) and second-phase (+31 ± 6%, P = 0.05) ISRs during the hyperglycemic clamp also improved. This was particularly evident when examined relative to the prevailing insulin resistance [1/(M/I)], as both first- and second-phase ISR markedly increased by 29 ± 7 ( P < 0.05) and 41 ± 8% ( P = 0.02). There was an inverse correlation between fasting FFA and first-phase ISR ( r2= 0.31, P < 0.02) and acute (2–4 min) glucose-induced insulin release after acipimox ( r2=0.52, P < 0.04). In this proof-of-concept study in FH+ individuals predisposed to T2DM, a 48-h reduction of plasma FFA improves day-long meal and glucose-stimulated insulin secretion. These results provide additional evidence for the important role that plasma FFA play regarding insulin secretion in FH+ subjects predisposed to T2DM.
Basal and insulin-regulated free fatty acid and glucose metabolism in humans
Authors: Shadid Samyah , Kanaley Jill A. , Sheehan Michael T. , Jensen Michael D.
Published: February 2007

These studies were done to examine the effects of body composition, resting energy expenditure (REE), sex, and fitness on basal and insulin-regulated FFA and glucose metabolism. We performed 137 experiments in 101 nondiabetic, premenopausal women and men, ranging from low normal weight to class III obese (BMI 18.0–40.5 kg/m2). Glucose flux was measured using [6-2H2]glucose and FFA kinetics with [9,10-3H]oleate under either basal (74 experiments) or euglycemic hyperinsulinemic (1.0 mU·kg FFM−1·min−1) clamp conditions (63 experiments). Consistent with our previous findings, REE and sex independently predicted basal FFA flux, whereas fat-free mass was the best predictor of basal glucose flux; in addition, percent body fat was independently and positively associated with basal glucose flux (total r2 = 0.52, P < 0.0001). Insulin-suppressed lipolysis remained significantly associated with REE ( r = 0.25, P < 0.05), but percent body fat also contributed (total adjusted r2 = 0.36, P < 0.0001), whereas sex was not significantly related to insulin-suppressed FFA flux. Glucose disposal during hyperinsulinemia was independently associated with peak V̇o2, percent body fat, and FFA concentrations (total r2 = 0.63, P < 0.0001) but not with sex. We conclude that basal glucose production is independently related to both FFM and body fatness. In addition, hyperinsulinemia obscures the sex differences in FFA release relative to REE, but brings out the effects of fatness on lipolysis.
Gill membrane remodeling with soft-water acclimation in zebrafish (Danio rerio)
Authors: Craig Paul M. , Wood Chris M. , McClelland Grant B.
Published: February 2007

Little is known regarding the ionoregulatory abilities of zebrafish exposed to soft water despite the popularity of this model organism for physiology and aquatic toxicology. We examined genomic and nongenomic changes to gills of zebrafish as they were progressively acclimated from moderately hard freshwater to typical soft water over 7 days and held in soft water for another 7 days. Gills were sampled daily and mRNA expression levels of gill Na+-K+-ATPase (NKA) α1a subunit, epithelium calcium channel (ECaC), carbonic anhydrase-1 and 2 (CA-1, CA-2), Na+/H+exchanger (NHE-2), V-type proton (H+)-ATPase, and copper transport protein (CTR-1) were quantified by real-time PCR. Changes in enzyme activities of gill NKA were determined and protein levels of NKA and ECaC were quantified by Western blotting. Levels of mRNA for ECaC increased fourfold after day 6, with an associated increase in ECaC protein levels after 1 wk in soft water. CA-1 and CA-2 exhibited a 1.5- and 6-fold increase in gene expression on days 6 and 5, respectively. Likewise, there was a fivefold increase in NHE-2 expression after day 6. Surprisingly, CTR-1 mRNA showed a large transient increase (over threefold) on day 6, while H+-ATPase mRNA did not change. These data demonstrate a high degree of phenotypic plasticity in zebrafish gills exposed to an ion-poor environment. This not only enhances our understanding of ionoregulatory processes in fish but also highlights the need for proper experimental design for studies involving preacclimation to soft water (e.g., metal toxicity).
Deconvoluting the intestine: molecular evidence for a major role of the mesenchyme in the modulation of signaling cross talk
Authors: Li Xing , Madison Blair B. , Zacharias William , Kolterud Åsa , States David , Gumucio Deborah L.
Published: February 2007

Reciprocal cross talk between the endodermally derived epithelium and the underlying mesenchyme is required for regional patterning and proper differentiation of the developing mammalian intestine. Though both epithelium and mesenchyme participate in patterning, the mesenchyme is thought to play a prominent role in the determination of the epithelial phenotype during development and in adult life. However, the molecular basis for this instructional dominance is unclear. In fact, surprisingly little is known about the cellular origins of many of the critical signaling molecules and the gene transcriptional events that they impact. Here, we profile genes that are expressed in the separate mesenchymal and epithelial compartments of the perinatal mouse intestine. The data indicate that the vast majority of soluble inhibitors and modulators of signaling pathways such as Hedgehog, Bmp, Wnt, Fgf, and Igf are expressed predominantly or exclusively by the mesenchyme, accounting for its ability to dominate instructional cross talk. We also catalog the most highly enriched transcription factors in both compartments. The results bolster previous evidence suggesting a major role for Hnf4γ and Hnf4α in the regulation of epithelial genes. Finally, we find that while epithelially enriched genes tend to be highly tissue restricted in their expression, mesenchymally enriched genes tend to be broadly expressed in multiple tissues. Thus, the unique tissue-specific signature that characterizes the intestinal epithelium is instructed and supported by a mesenchyme that itself expresses genes that are largely nontissue specific.
Sociocultural Predictors of Breast Cancer Risk Perceptions in African American Breast Cancer Survivors
Authors: Brewster Kiyona , Wileyto E. Paul , Kessler Lisa , Collier Aliya , Weathers Benita , Stopfer Jill E. , Domchek Susan , Halbert Chanita Hughes
Published: February 2007

Although African American breast cancer survivors are at increased risk for developing breast cancer again, empirical data are not available on breast cancer risk perceptions in these women. This study characterized perceived risk of developing breast cancer in African American breast cancer survivors at risk for having a BRCA1 or BRCA1 (BRCA1/2) mutation and identified factors having significant independent associations with risk perceptions. Participants were 95 African American breast cancer survivors at an increased risk for having a BRCA1/2 mutation. Risk perceptions and sociodemographic, clinical, treatment, and sociocultural factors were collected during a structured telephone interview. Most women reported that they had the same or lower risk of developing breast cancer again compared with other women (53%); however, a substantial minority of women (47%) reported that they had a higher or much higher risk. Factors having significant independent associations with heightened risk perceptions included having a ≥10% prior probability of having a BRCA1/2 mutation [odds ratio (OR), 2.91; 95% confidence interval (95% CI), 1.09-7.72; P = 0.03] and more years of formal education (OR, 2.74; 95% CI, 1.02-7.36; P = 0.05). In addition, women who thought about the past a lot were three times more likely to report heightened risk perceptions compared with those who did not think about the past a lot (OR, 3.72; 95% CI, 1.45-9.57; P = 0.01). These results suggest that it may be important to ensure adequate risk comprehension among African American women as part of genetic counseling for inherited breast-ovarian cancer risk. Discussion of risk perceptions within the context of existing beliefs and values may facilitate this process. (Cancer Epidemiol Biomarkers Prev 2007;16(2):244–8)
Lifetime Recreational and Occupational Physical Activity and Risk of In situ and Invasive Breast Cancer
Authors: Sprague Brian L. , Trentham-Dietz Amy , Newcomb Polly A. , Titus-Ernstoff Linda , Hampton John M. , Egan Kathleen M.
Published: February 2007

Numerous studies have observed reduced breast cancer risk with increasing levels of physical activity, yet these findings have been inconsistent about optimal times of activity and effect modification by other factors. We investigated the association between recreational and occupational physical activity and breast cancer risk in a population-based case-control study in Massachusetts, New Hampshire, and Wisconsin. During structured telephone interviews, 7,630 controls, 1,689 in situ, and 6,391 invasive breast cancer cases, ages 20 to 69 years, reported lifetime history of recreational physical activity and occupation. Neither lifetime recreational nor strenuous occupational physical activity appeared to be associated with risk of breast carcinoma in situ. In contrast, recreational physical activity was associated with a reduced risk of invasive breast cancer. After adjustment for potentially confounding factors, women averaging >6 h per week of strenuous recreational activity over their lifetime had a 23% reduction in the odds ratio of invasive breast cancer when compared with women reporting no recreational activity (95% confidence interval, 0.65-0.92; Ptrend = 0.05). However, this reduction in risk was limited to women without a first-degree family history of breast cancer (Pinteraction = 0.02). Inverse associations were observed for physical activity early in life, in the postmenopausal years, and in the recent past, but these findings were confined to women without a family history of breast cancer. Lifetime strenuous occupational activity was not associated with invasive breast cancer risk. These results provide further evidence that, for most women, physical activity may reduce the risk of invasive breast cancer. (Cancer Epidemiol Biomarkers Prev 2007;16(2):236–43)
What Do Women in the U.S. Know about Human Papillomavirus and Cervical Cancer?
Authors: Tiro Jasmin A. , Meissner Helen I. , Kobrin Sarah , Chollette Veronica
Published: February 2007

Background: Women need to understand the link between human papillomavirus (HPV) and cervical cancer in order to make appropriate, evidence-based choices among existing prevention strategies (Pap test, HPV DNA test, and HPV vaccine). Assessment of the public's knowledge in nationally representative samples is a high priority for cervical cancer control.

Objectives: To assess factors associated with U.S. women's awareness of HPV and knowledge about its link to cervical cancer.

Methods: Analyzed cross-sectional data from women ages 18 to 75 years old responding to the 2005 Health Information National Trends Survey (n = 3,076).

Results: Among the 40% of women who had ever heard about HPV, <50% knew it caused cervical cancer; knowledge that HPV was sexually transmitted and caused abnormal Pap tests was higher (64% and 79%, respectively). Factors associated with having heard about HPV included: younger age, being non–Hispanic White, higher educational attainment, exposure to multiple health information sources, trusting health information, regular Pap tests, awareness of changes in cervical cancer screening guidelines, and having tested positive for HPV. Accurate knowledge of the HPV-cervical cancer link was associated with abnormal Pap and positive HPV test results.

Conclusions: Awareness about HPV among U.S. women is low. Having heard about HPV did not ensure accurate knowledge. Strategies for communicating accurate information about HPV transmission, prevention, and detection as well as risk and treatment of cervical cancer are needed. (Cancer Epidemiol Biomarkers Prev 2007;16(2):288–94)
The Prevalence of BRCA2 Mutations in Familial Pancreatic Cancer
Authors: Couch Fergus J. , Johnson Michele R. , Rabe Kari G. , Brune Kieran , de Andrade Mariza , Goggins Michael , Rothenmund Heidi , Gallinger Steven , Klein Alison , Petersen Gloria M. , Hruban Ralph H.
Published: February 2007

Mutations in the BRCA2 gene have been implicated in pancreatic cancer susceptibility through studies of high-risk breast and ovarian cancer families. To determine the contribution of mutations in BRCA2 to familial pancreatic cancer, we screened affected probands from 151 high-risk families identified through pancreatic cancer clinics for germ-line BRCA2 mutations. Of these families, 118 had two or more first- and second-degree relatives with pancreatic cancer, and an additional 33 had two or more affected second-degree relatives. The average age of onset for pancreatic cancer was 62.8 years. Five BRCA2 truncating mutations were identified, three in families with two or more first- and second-degree relatives with pancreatic cancer. Three of the families with mutations had a history of breast cancer but not ovarian cancer. Four of five families with mutations were identified through probands with early-onset (<55 years) pancreatic cancer. The results of this study were combined with those from a BRCA2 mutation study of 29 other families from the same Johns Hopkins University National Familial Pancreatic Tumor Registry to estimate the frequency of BRCA2 mutations. A total of 10 carriers from 180 families were identified, suggesting that BRCA2 mutations account for 6% of moderate and high-risk pancreatic cancer families. (Cancer Epidemiol Biomarkers Prev 2007;16(2):342–6)
Smoking, Helicobacter pylori Virulence, and Type of Intestinal Metaplasia in Portuguese Males
Authors: Peleteiro Bárbara , Lunet Nuno , Figueiredo Céu , Carneiro Fátima , David Leonor , Barros Henrique
Published: February 2007

High-virulence Helicobacter pylori strains and smoking increase the risk of gastric precancerous lesions. However, its association with specific types of intestinal metaplasia has been poorly studied. We aimed to quantify the association between different types of intestinal metaplasia (complete, incomplete, and mixed) and these two risk factors. Male volunteers (n = 227) underwent an upper digestive endoscopy and completed symptoms and lifestyle questionnaires. A histologic diagnosis was assigned based on the lesions found in any of the biopsy specimens (antrum, body, or incisura). H. pylori vacA and cagA were directly genotyped by multiplex PCR and reverse hybridization. Each participant's smoking status at the time of endoscopy was assessed. Logistic and multinomial logistic regression models were fitted (including H. pylori virulence, smoking, age, and education as independent variables) using normal/chronic nonatrophic gastritis as the reference category. Compared with never smokers infected with low-virulence strains, the risk of intestinal metaplasia was increased in subjects infected with high-virulence strains [odds ratio (OR), 5.74; 95% confidence interval (95% CI), 1.68-19.63] and in ever smokers (OR, 3.54; 95% CI, 1.30-9.61). In ever smokers infected with high-virulence H. pylori strains, the risk of intestinal metaplasia was further increased (OR, 8.61; 95% CI, 3.07-24.17). Infection with high-virulence strains significantly increased the risk of incomplete (OR, 9.81; 95% CI, 2.39-40.31) and mixed (OR, 3.28; 95% CI, 1.51-7.14) intestinal metaplasia. Complete (OR, 2.82; 95% CI, 1.01-7.88) and mixed (OR, 2.97; 95% CI, 1.12-7.84) intestinal metaplasia were more frequent among ever smokers. High-virulence H. pylori strains and smoking are differentially associated with the complete and incomplete types of intestinal metaplasia, suggesting divergent pathways in gastric carcinogenesis. (Cancer Epidemiol Biomarkers Prev 2007;16(2):322–6)
Slippage after Adjustable Gastric Banding according to the Pars Flaccida and the Perigastric Approach
Authors: Khoursheed M. , Al-Bader I. , Mohammad A.I. , Soliman M.O. , Dashti H.
Published: February 2007

Objective: To evaluate laparoscopic adjustable gastric banding and the ‘pars flaccida’ techniques for treating morbidly obese patients. Subjects and Methods: Between May 1999 and July 2002, 64 patients underwent laparoscopic adjustable gastric banding. The ‘perigastric’ technique was performed in the first 31 patients. From September 2000 the band was positioned according to the ‘pars flaccida’ technique in the remaining 33 patients. The patients were divided into three groups: group 1 – ‘perigastric’ technique using Lap-Band size 9.75 and 10 cm (31 patients); group 2 – ‘pars flaccida’ technique using Lap-Band size 10 cm (12 patients), and group 3 – ‘pars flaccida’ technique using the Swedish band (21 patients). There were 58 females and 6 males with a mean age of 36.6 years (range 17–56). The preoperative mean body mass index was 46.2 kg/m2. Results: Band slippage occurred in 10/31 patients (32.2%) of group 1, 3/12 patients (25%) of group 2 and none in group 3 patients (p < 0.01). Conclusion: The ‘pars flaccida’ technique significantly reduces the incidence of postoperative slippage after gastric banding. This complication is further reduced in the Swedish band group. Furthermore, we do not recommend using the 10-cm Lap-Band in the ‘pars flaccida’ technique.
Eradication Therapy in Helicobacter pylori-Positive Patients with Halitosis: Long-Term Outcome
Authors: Katsinelos Panagiotis , Tziomalos Kostas , Chatzimavroudis Grigoris , Vasiliadis Themistoklis , Katsinelos Taxiarchis , Pilpilidis Ioannis , Triantafillidis Ioannis , Paroutoglou George , Papaziogas Basilis
Published: February 2007

Objective: The aim of this study was to investigate the incidence and long-term outcome of halitosis before and after eradication therapy in patients with functional dyspepsia and Helicobacter pylori infection. Subjects and Methods: Halitosis and dyspepsia-related symptoms were investigated by way of a questionnaire. Only patients with functional dyspepsia, H. pylori infection and no histological evidence of atrophy were included in the study. A total of 18 patients fulfilled these criteria and completed the study. Four to six weeks after the end of eradication treatment, endoscopy or [13C] breath test was performed to check for H. pylori in the gastric mucosa. Halitosis and dyspeptic symptoms were re-evaluated during and at the end of follow-up. Results:H. pylori infection was eradicated in all patients, in the 14/18 patients (77.8%) with triple drug therapy, and the 4/18 patients (22.2%) with quadruple drug therapy. During the follow-up period (mean 55.8 ± 21.3 months (range 6–108 months)) resolution of halitosis was observed in 16/18 patients (88.9%), while 2 patients (11.1%) (p < 0.001) continued to present with halitosis. Also, eradication therapy resulted in statistically significant relief of all dyspeptic symptoms, except bloating. Conclusion: Eradication of H. pylori in patients with functional dyspepsia and halitosis results in sustained resolution of halitosis during long-term follow-up in the majority of cases. This finding supports the existence of a link between H. pylori infection and halitosis and suggests that H. pylori eradication might be considered in patients with halitosis.