bluuebunny/crossref_metadata_2025 huggingface dataset:
A RADIOCARBON‐DATED POLLEN DIAGRAM FROM LOCH OF WINLESS, CAITHNESS, NORTH‐EAST SCOTLAND
Authors: PEGLAR SYLVIA
Published: June 2006

Summary

A pollen diagram is presented from a 6 metre continuous core taken from Loch of Winless. Ten radiocarbon age determinations have been made from the sediments in relation to pollen stratigraphical changes and the sediments are found to cover the past 12800 years.

On the basis of pollen stratigraphy the diagram is divided into five local pollen assemblage zones. Zones 1 and 2 may be correlated with the younger part of the Late Devensian (sensu Mitchell et al., 1973) whilst zones 3, 4 and 5 cover the Flandrian up to the present.

The most notable aspect of the vegetational history of the area inferred from the fossil assemblages is the lack of tree‐cover at any time since the last glaciation. With the climatic amelioration at the beginning of the Flandrian period (approximately 10000 years B.P.), ‘dwarf‐shrub’ and ‘dwarf‐herb’ communities typical of the Late Devensian contracted and there was a widespread expansion of rich ‘tall‐herb’ and fern‐dominated communities with some small patches of willow and hazel scrub in sheltered sites. These in turn gave way to Calluna‐dominated heaths on the well drained soils where podsolization and acidification were occurring.
A HOLOCENE VEGETATION RECORD FROM THE EASTERN SIDE OF WILSONS PROMONTORY, VICTORIA
Authors: LADD P. G.
Published: June 2006

Summary

Pollen analysis of sediment at a site on the eastern side of Wilsons Promontory (southern Australia) privides a record of the vegetation from about 13 000 B.P. to the present. A Eucalyptus forest was present on the site at first, but was replaced by a Melaleuca scrub or thicket about 11000 B.P., probably reflecting a rise in the watertable. As the sea was at least 6 km distant, this event may mark increasing rainfall near the start of the Holocene. The arrival of the sea close to the site about 7000 years ago is demonstrated by changes from a freshwater swamp to saline salt marsh, followed by succession to the low scrub swamp of the present.

Regionally, the Nothofagus rainforest, which is now restricted to small isolated stands on high parts of the promontory, expanded between 11 000 and 7000 B.P. This forest is now more extensive than at 11000 B.P. but has contracted relative to the mid‐Holocene extent. From this it appears that the climate of this region during the mid‐Holocene was slightly wetter than that of the early or late Holocene.

The later half of the record is in agreement with other work from the western side of Wilsons Promontory.
Multipolar Endocardial Mapping of the Right Heart Using a Basket Catheter: Acute and Chronic Animal Studies
Authors: TRIEDMAN JOHN K. , JENKINS KATHY J. , COLAN STEVEN D. , VAN PRAAGH RICHARD , LOCK JAMES E. , WALSH EDWARD P.
Published: June 2006

The development of catheter‐based ablative techniques for primary atrial and ventricular arrhythmias is likely to be assisted by improved techniques for systematic endocardial activation sequence mapping. RA mapping using a multielectrode basket catheter has been shown to be feasible with minimal acute toxicity in a prior study. The objectives of the current study are to investigate: (1) the utility of the basket catheter for mapping RV activation; and (2) the evolution of acute endocardial lesions produced by basket catheter use in both the RA and RV over 4–8 weeks time. A flexible, 5‐spoke basket catheter bearing 25 electrode pairs was placed in the RA (n = 9) or the RV (n = 13) in 22 juvenile sheep (22–56 kg). The catheter was deployed for 0.1–4.1 hr (RA) and 0.3–3.9 hr (RV). In 20 of these 22 animals, 32 recordings were made of filtered (30–250 Hz) bipolar electrograms and surface ECG. Electrograms were timed and used to construct activation sequences based on a schematic of catheter geometry. Hearts were examined either acutely (4 RA and 9 RV studies) or 4–8 weeks after tbe procedure (5 RA and 4 RV studies). One animal undergoing RA placement had an air embolism resulting in cardiac arrest immediately prior to basket placement; all other animals were stable during placement. RA electrograms of sufficient quality to determine activation time were recorded from 82% of pairs in RA maps, and RV electrograms from 89% of pairs in RV maps. Mean activation sequence duration in RV was 16 ms versus 47 ms in RA (P < 0.0001), making construction of RV maps more difficult. Acute postmortem studies of RV placement revealed a silent apical RV puncture in one animal. Superficial abrasion or ecchymosis of RV endocardium and/or tricuspid valve were noted in six animals. Postmortem exams in both RA and RV chronic studies showed healed endocardial lesions, with only superficial scarring. Rapid RV activation mapping using a basket catheter is feasible, but requires precision recording techniques. Endocardial abrasions produced in lambs both by RA and RV placement of the catheter are healed in < 4–8 weeks, with trivial residua. The multielectrode basket catheter may be applicable to the mapping of tachycardias originating in or involving the right ventricle.
Low Energy Transvenous Cardioversion of Short Duration Atrial Tachyarrhythmias in Humans Using a Single Lead System
Authors: HEISEL ARMIN , JUNG JENS , FRIES ROLAND , STOPP MATTHIAS , SEN SEMI , SCHIEFFER HERMANN , ÖZBEK GEM
Published: June 2006

The purpose of this study was to investigate the efficacy and safety of atrial cardioversion using an endocardial single lead system presently used for ventricular defibrillation. The study population consisted of 26 recipients of an ICD in combination with a conventional endocardial single lead system with the proximal spring electrode as anode in the SVC and the distal as cathode in the apex of the RV. Atrial tachyarrhythmias were induced by right atrial burst pacing. If the arrhythmia sustained > 1 minute, biphasic shocks synchronized with the R wave were delivered using the implanted device, beginning with an energy of 4 J. If 4 J failed to terminate the arrhythmia, energy was increased stepwise, if the first shock was successful, a step‐down testing was performed after reinduction of atrial tachyarrhythmias. The mean atrial defibrillation threshold was 2.3 ± 1.2 J (range, 0.5–5 J). A total of 154 shocks were delivered and no adverse effects were observed. The mean defibrillation threshold for atrial flutter was somewhat lower than that for AF (1.8 ± 1 J vs 2.7 ± 1.4 J, P = 0.08). There was no correlation between the atrial defibrillation threshold and a history of previously occurring atrial tachyarrhythmias, the kind of the underlying heart disease, a prescription of antiarrhythmic drugs, the dimension of the LA, the LVEF, or the ventricular DFT. Internal atrial cardioversion of short duration atrial tachyarrhythmias using a transvenous single lead system designed for ventricular defibrillation is feasible and safe at low energies, and may have important clinical applications.
Pacing Induced Ventricular Fibrillation in Internal Cardioverter Defibrillator Patients: A New Form of Proarrhythmia
Authors: VLAY LINDA C. , VLAY STEPHEN C.
Published: June 2006

Current model internal cardioverter defibrillators (ICDs) have cardioversion, defibrillation, pacemaker, and telemetry function. Telemetry documents arrhythmia and facilitates therapeutic adjustments. We report two cases of pacing induced VF terminated by the defibrillator, with the device responsible for both initiation and correction of the arrhythmia.
Transmembrane Potentials During High Voltage Shocks in Ischemic Cardiac Tissue
Authors: HOLLEY LORAINE K. , KNISLEY STEPHEN B.
Published: June 2006

Transmembrane, voltage sensitive fluorescent dye (TMF) recording techniques have shown that high voltage shocks (HVS), typically used in defibrillation, produce either hyper‐ or depolarization of the transmembrane potential (TMP) when delivered in the refractory period of an action potential (AP) in normal cardiac tissue (NT). Further, HVS produce an extension of the AP, which has been hypothesized as a potential mechanism for electrical defibrillation. We examined whether HVS modify TMP of ischemic tissue (IT) in a similar manner. In seven Langendorff rabbit hearts, recordings of APs were obtained in both NT and IT with TMF using di‐4‐ANEPPS, and diacetylmonoxime (23 μM) to avoid motion artifacts. Local ischemia was produced by occlusion of the LAD. HVS of either biphasic (5 + 5 ms) or (3 + 2 ms) or monophasic shapes (5 ms) were delivered at varying times (20%–90%) of the paced AP. Intracardiac ECG and TMF recordings of the TMP were each amplified, recorded, and digitized at a frequency of 1 kHz. The paced AP in IT was triangular in shape with no obvious phase 3 plateau, typically seen in NT. There was normally a reduced AP amplitude (expressed as fractional fluorescence) in IT (2.6%± 1.79%) compared to 3.8%± 0.66% in NT, and shortened AP duration (137 ± 42 vs 171 ± 11 ms). One hundred‐Volt HVS delivered during the refractory period of paced AP in IT in five rabbits, elicited a depolarization response of the TMP with an amplitude up to three times greater than the paced AP. This is in contrast to NT where the 100‐V HVS produced hyperpolarization in four hearts, and only a slight depolarization response in one heart. These results suggest that HVS, typically delivered by a defibrillation shock, modify TMPs in a significantly different manner for ischemic cells, which may influence success in defibrillation.
Clinical Results with Electrophysiologist‐Implanted Cardioverter‐Defibrillators
Authors: SINGER IGOR , DEAM GREGORY , PAYNE VAUGHN , CICIC AIDA , MARTIN THEDA
Published: June 2006

With the advent of nonthoracotomy leads and smaller devices. implantation techniques for implantable cardioverters defibrillators (ICDs) have been simplified. We reviewed the outcome of pectoral ICD implantation by electrophysiologists in 51 consecutive patients, 47 males and 4 females, mean age 60 ± 12 years, presenting with aborted sudden cardiac death (14) and drug refractory hypotensive ventricular tachycardia (37). Patients were implanted with either the PCD JewelTM 7219D (37) or 72197C (14) Medtronic pectoral ICDs. The mean operative time was 98 ± 31 minutes. There was no operative mortality. Complications occurred in 2 (4%) patients: right ventricular lead dislodgement requiring lead repositioning occurred in 1 patient, and 1 patient treated with anticoagulants, who had received a subcutaneous patch lead, developed a hematoma not requiring surgical reintervention. The mean defibrillation threshold was 18.6 ± 5.5 J, but was significantly lower for the 7219C(14.1 ± 5.0 J) compared to the 7219D (20.6 ± 4.4J) device, P = 0.0001. A two‐lead system consisting of a right ventricular electrode (RVA) and a superior vena caval lead (SVC) was utilized in 29, RVA/SVC‐subcutaneous patch in 5 and active can in 17 patients, Patients were discharged after 4.3 ± 3 days. The procedure time was significantly shorter for the 7219C device (79.7 ± 18.9 vs 105.2 ± 32.8 minutes., P = 0.0035]. Over the fallow‐up period of 8 ± 5 (range 1–20] months, 26% patients received appropriate therapy (95% antitachycardia pacing, 5% shock). Concomitant antiarrhythmic therapy was utilized in 41% of patients. Ninety‐eight percent of patients are alive. One patient died of congestive heart failure. Clinical results with electrophysiologist‐implanted pectoral ICDs demonstrate lou morbidity and no operative mortality in this clinical series and lower DFTs and shorter procedure times may be achieved with 7219C (active can) device.
Initial Clinical Experience with an Implantable Human Atrial Defibrillator
Authors: LAU CHU‐PAK , TSE HUNG‐FAT , LOK NGAI‐SANG , LEE KATHY L.F. , HO DAVID S.W. , SOPHER MARK , MURGATROYD FRANCIS , CAMM A. JOHN
Published: June 2006

Low energy biatrial shock is an effective means of restoring sinus rhythm in patients with atril fibrillation (AF). Ventricular proarrhythmia is avoided provided that shocks are well synchronized to R waves that are not at closely coupled intervals or preceded by long‐short cycles. Based on these principles, an implantable atrial defibrillator has been developed and was implanted in three patients with drug refractory paroxysmal AF. The device detects AF via an actively fixed right atrial and a self‐retaining coronary sinus defibrillating leads, and delivers 3/3 ms biphasic shocks up to 300 V synchronized to the R wave. The mean implant threshold (ED50) was 195V (1.8 J), and minimum voltage at conversion during follow‐up assessments at 1, 3, and 6 months were 260 V, 2.5 J, 250 V, 2.3 J, and 300 V, 3.0 J respectively. Detection of AF was 100% specific and shocks were 100% synchronized, although only a proportion of synchronized R waves were considered suitable for shock delivery primarily because of closely coupled cycles. Three patients had 9 spontaneous AF episodes. 8/9 (89%) successfully defibrillated by shocks of 260–300 V. Sedation was not used in 4 out of 9 (45%) episodes. Backup ventricular pacing was initiated by the device in 6 out of(67%) episodes. One patient had more frequent AF after lead placement, which subsided after a change of medication. There was no ventricular proarrhythmia. It is concluded that an implantable atrial defibrillator is a viable therapy for selected patients with paroxysmal AF. The device is capable of accurate AF detection, R wave synchronization and ventricular support pacing after successful defibrillation of AF.
Quality‐of‐Life of Pacemaker Patients: A Reappraisal of Current Instruments
Authors: STOFMEEL MONIQUE A.M. , POST MARCEL W.M. , KELDER JOHANNES C. , GROBBEE DIEDERICK E. , VAN HEMEL NORBERT M.
Published: June 2006

Current clinical practice permits the use of single chamber ventricular or dual chamber pacemakers. However, it is not known which type of pacemaker results in superior clinical and patient outcomes. This is of growing importance because of the higher costs and increased risk of technical failures of dual chamber pacemakers. Patient outcomes can be assessed with quality of life questionnaires, but it is unclear which questionnaires are valid for use in pacemaker patients. This article reappraises studies on quality of life instruments for pacemaker patients. We searched MEDLINE (1985–1998) for studies assessing quality‐of‐life in general and in pacemaker patients. The SF‐36 appeared to be the best among generic questionnaires because of its psychometric characteristics and experience of use. Concerning disease specific instruments, the Karolinska quality of life questionnaire has desirable content validity but lacks more rigorous psychometric validation, which constitutes a serious limitation. Previous studies suggested that implantation of atrioventricular pacemakers improves quality‐of‐life compared to ventricular pacemakers, but since no well‐designed and validated questionnaire exists, these results should be interpreted with caution. The best outcome measure to evaluate quality‐of‐life in pacemaker patients would be a combination of a generic health profile with established reliability and validity supplemented with a cardiovascular assessment adjusted to suit pacemaker patients. By doing so, individual scores can be compared within a disease cohort and to same‐aged, nondiseased persons, as well as other diseased populations. The development and validation of such an instrument is currently needed.
Initial Results with Left Ventricular Pacemaker Lead Implantation Using a Preformed “Peel‐Away” Guiding Sheath and “Side‐Wire” Left Ventricular Pacing Lead
Authors: WALKER STUART , LEVY TERRY , REX STEPHEN , PAUL VINCE
Published: June 2006

We report our preliminary experience with the use of preformed “peel‐away” guiding sheaths and “side‐wire” pacing leads for permanent biventricular pacemaker insertion in 13 patients with heart failure. Three of these patients were undergoing an upgrade of a preexistent VVIR pacing system after prior His ablation for medically refractory atrial fibrillation. Six of the patients had undergone attempted biventricular pacemaker insertion, but required left ventricular lead repositioning after total implantation failure or late displacement of the lead. The remaining patients were undergoing new system implantation. Target vessel cannulation was achieved in all patients. However, in one patient, diaphragmatic pacing throughout the target vessel length prevented successful implantation. All other implants were ultimately successful (92% success rate). We conclude that device implantation using a preformed sheath and side‐wire pacing lead is feasible and may offer significant benefits over implantation with currently available technology.
Mid‐term report on the project “Disaster nursing in a ubiquitous society” in the academic years 2003 and 2004
Authors: YAMAMOTO Aiko
Published: June 2006

Aim:  This is the mid‐term report of the project titled “Disaster nursing in a ubiquitous society”, funded by the Japanese Government. The purpose of this project is to develop the self‐care abilities of communities and individuals to independently regenerate and recover from the consequences of disasters.

Methods:  The methods utilized in this project were questionnaires sent by post or placed on websites, and interviews. The participants in our research were people with special needs in the case of a disaster, nursing professionals, ordinary people, and other professionals.

Results:  During 2003 and 2004, there were activities that progressed according to the original plans, activities that progressed at a faster rate than foreseen in the original plans, and newly expanded research activities that were conducted. New academic knowledge gained from the project activities includes five factors for disaster preparedness, six common issues related to health, care, training, and others, six categories of necessary factors in nursing activities, the clarification of the support needs of care‐providers, and the clarification of specific groups with unique needs including children, pregnant and postpartum women, elderly people, people with chronic conditions, cancer patients, and care‐providers.

Conclusions:  The growing recognition of our center as a global base of disaster nursing is indicated by the fact that we receive numerous requests from Japan and abroad, that our suggestions influence some governmental policies, and that we take initiatives in promoting the concept of disaster nursing throughout the world. It is necessary to disseminate the results of this project, to develop further knowledge, to clarify future challenges related to disasters, and to contribute to the preparedness of people and communities.
Dilemmas facing Japanese nurses regarding the physical restraint of elderly patients
Authors: YAMAMOTO Miwa , IZUMI Kyoko , USUI Kimika
Published: June 2006

Aim:  The purpose of this study was to clarify the meaning of “dilemma” regarding the use of physical restraint on elderly persons as described by nurses in general wards at community hospitals. The questions asked included: to what extent has the dilemma of nurses regarding the restraint of elderly persons in the general ward been clarified?, which factor/s compose the dilemma?, what are the psychometric properties of the factors?, and how should nurses deal with the dilemma with regard to restraining elderly persons?

Methods:  The participants were 1477 nurses (12 male, 1463 female, and two: no answer) at 54 wards (excluding the emergency wards of psychiatry, pediatrics, obstetrics, outpatients, operating rooms, and intensive care units). The dilemma was measured by using a questionnaire consisting of 20 items previously developed by the author.

Results:  An explanatory factor analysis revealed four dilemma factors among 17 items investigated. These were “execution of treatment and security”, “characteristics in nursing of elderly patients”, “a cooperative relationship”, and “priorities in nursing”. The cumulative contribution ratio was 68.3%. In respect to the dilemma where nurses are faced with the physical restraint of elderly persons, four factors in the clarification of the dilemma were extracted: “execution of treatment and security”, “characteristic features in nursing”, “a cooperative relationship in nursing”, and “priorities in nursing”.

Conclusions:  Based on the psychometric properties, the Dilemma scale is a valid and reliable tool. The construction of four systems to cope with these dilemmas is suggested. These systems would enable practising nurses to communicate with comedical workers in order to reach a consensus about the elderly’s care, avoid restraining the elderly by allocating care specialists to the elderly, establish institutional policies and safety standards that establish the nurses’ responsibilities for patients’ decision‐making, and receive continuous and timely ethical education.
EFFICIENT DESCRIPTION FOR π AND σ MESONS BY RESONATING MEAN-FIELD APPROXIMATION TO TWO-FLAVOR NAMBU-JONA-LASINIO MODEL
Authors: NISHIYAMA SEIYA , DA PROVIDÊNCIA JOÃO , OHNO OSAMU
Published: June 2006

We have applied the resonating (Res-) mean-field approximation (MFA) to fermion systems with large quantum fluctuations over the usual MFA to a naive Nambu-Jona-Lasinio (NJL) model involving no current quark mass term. In our approach, as part of the model the normalization volume is kept finite, which plays an important role. This attempt has been quite successful in explaining the pion and sigma-meson masses, but the values of the order parameter for quark condensate and the pion decay constant are too small. This fact suggests us that the Res-MFA including no isospin causes such a problem. To avoid the serious drawback, if we naturally extend the NJL model to include two-flavor degrees of freedom and make an SU(2)fresonating Hartree-Fock (Res-HF) approximation, it is expected that the magnitudes of the order parameter and the pion decay constant are much improved. Using this extended NJL model, they are calculated again and both the numerical values [Formula: see text] and fπreach good agreements with their experimental ones.
FORM FACTORS OF ργ*→π0and γγ*→π0TRANSITIONS FROM THE FINITE-WIDTH LIGHT-CONE LOCAL QCD SUM RULES
Authors: ZHANG ZHENYU , ZHANG SHENGXI , LIU JUEPING
Published: June 2006

Instead of the usual zero-width approximation, the finite-width approximation for the resonance, the ρ-ω mesons, is used to investigate the light-cone local QCD sum rules for the form factors of the transitions, ργ*→π0and γγ*→π0. To be more certain, a product of two weight functions is chosen in the method of the analytic continuation by duality to annihilate the uncertainty in the continuum region and the integrand in the integration range not covered by vector-meson dominance and where the theoretical expression may least be trusted. The resultant form factors in the cases for the zero- and finite-widths are almost the same, both agree well with the experimental measurements, and comparison with the results from the Laplacian transformed light-cone sum rules and etc. is discussed.
EQUATION OF STATE OF HOT NUCLEAR AND NEUTRON MATTER: A STATISTICAL APPROACH
Authors: MOSHFEGH H. R.
Published: June 2006

The symmetric nuclear and neutron matter equation of state at finite temperature are calculated in the frame of the Thomas-Fermi approximation using the effective nucleon-nucleon interaction of Myers and Swiatecki. By introducing an effective mass in distribution function as a variational parameter, the effect of temperature on pressure, entropy, specific heat capacity, incompressibility and binding energy is discussed. A critical temperature of 17.2 MeV and a critical exponent of 0.32 for symmetric nuclear matter is found and we find that there is no phase transition in the neutron matter system. The results of calculations are in good agreement with experimental prediction and other theoretical results.
Beneficial effects of a long-term oral l-arginine treatment added to a hypocaloric diet and exercise training program in obese, insulin-resistant type 2 diabetic patients
Authors: Lucotti Pietro , Setola Emanuela , Monti Lucilla D. , Galluccio Elena , Costa Sabrina , Sandoli Emilia P. , Fermo Isabella , Rabaiotti Giovanni , Gatti Roberto , Piatti PierMarco
Published: June 2006

Because chronic l-arginine supplementation improves insulin sensitivity and endothelial function in nonobese type 2 diabetic patients, the aim of this study was to evaluate the effects of a long-term oral l-arginine therapy on adipose fat mass (FM) and muscle free-fat mass (FFM) distribution, daily glucose levels, insulin sensitivity, endothelial function, oxidative stress, and adipokine release in obese type 2 diabetic patients with insulin resistance who were treated with a combined period of hypocaloric diet and exercise training. Thirty-three type 2 diabetic patients participated in a hypocaloric diet plus an exercise training program for 21 days. Furthermore, they were divided into two groups in randomized order: the first group was also treated with l-arginine (8.3 g/day), and the second group was treated with placebo. Although in the placebo group body weight, waist circumference, daily glucose profiles, fructosamine, insulin, and homeostasis model assessment index significantly decreased, l-arginine supplementation further decreased FM ( P < 0.05) and waist circumference ( P < 0.0001), preserving FFM ( P < 0.03), and improved mean daily glucose profiles ( P < 0.0001) and fructosamine ( P < 0.03). Moreover, change in area under the curve of cGMP (second messenger of nitric oxide; P < 0.001), superoxide dismutase (index of antioxidant capacity; P < 0.01), and adiponectin levels ( P < 0.02) increased, whereas basal endothelin-1 levels ( P < 0.01) and leptin-to-adiponectin ratio ( P < 0.05) decreased in the l-arginine group. Long-term oral l-arginine treatment resulted in an additive effect compared with a diet and exercise training program alone on glucose metabolism and insulin sensitivity. Furthermore, it improved endothelial function, oxidative stress, and adipokine release in obese type 2 diabetic patients with insulin resistance.
Patterns in food intake correlate with body mass index
Authors: Periwal Vipul , Chow Carson C.
Published: June 2006

Quantifying eating behavior may give clues to both the physiological and behavioral mechanisms behind weight regulation. We analyzed year-long dietary records of 29 stable-weight subjects. The records showed wide daily variations of food intake. We computed the temporal autocorrelation and skewness of food intake mass, energy, carbohydrate, fat, and protein. We also computed the cross-correlation coefficient between intake mass and intake energy. The mass of the food intake exhibited long-term trends that were positively skewed, with wide variability among individuals. The average duration of the trends ( P = 0.003) and the skewness ( P = 0.006) of the food intake mass were significantly correlated with mean body mass index (BMI). We also found that the lower the correlation coefficient between the energy content and the mass of food intake, the higher the BMI. Our results imply that humans in neutral energy balance eating ad libitum exhibit a long-term positive bias in the food intake that operates partially through the mass of food eaten to defend against eating too little more vigorously than eating too much.
Insulin resistance induced by hydrocortisone is increased in patients with abdominal obesity
Authors: Darmon Patrice , Dadoun Frédéric , Boullu-Ciocca Sandrine , Grino Michel , Alessi Marie-Christine , Dutour Anne
Published: June 2006

Glucocorticoids hypersensitivity may be involved in the development of abdominal obesity and insulin resistance. Eight normal weight and eight obese women received on two occasions a 3-h intravenous infusion of saline or hydrocortisone (HC) (1.5 μg·kg−1·min−1). Plasma cortisol, insulin, and glucose levels were measured every 30 min from time−30(min) (time−30) to time240. Free fatty acids, adiponectin, and plasminogen activator inhibitor-1 (PAI-1) levels were measured at time−30, time180, and time240. At time240, subjects underwent an insulin tolerance test to obtain an index of insulin sensitivity (KITT). Mean30–240cortisol level was similar in control and obese women after saline (74 ± 16 vs. 75 ± 20 μg/l) and HC (235 ± 17 vs. 245 ± 47 μg/l). The effect of HC on mean180–240insulin, mean180–240insulin resistance obtained by homeostasis model assessment (HOMA-IR), and KITTwas significant in obese (11.4 ± 2.0 vs. 8.2 ± 1.3 mU/l, P < 0.05; 2.37 ± 0.5 vs. 1.64 ± 0.3, P < 0.05; 2.81 ± 0.9 vs. 3.32 ± 1.02%/min, P < 0.05) but not in control women (3.9 ± 0.6 vs. 2.8 ± 0.5 mU/l; 0.78 ± 0.1 vs. 0.49 ± 0.1; 4.36 ± 1.1 vs. 4.37 ± 1.2%/min). In the whole population, the quantity of visceral fat, estimated by computerized tomography scan, was correlated with the increment of plasma insulin and HOMA-IR during HC infusion [Δmean30–240insulin ( r = 0.61, P < 0.05), Δmean30–240HOMA-IR ( r = 0.66, P < 0.01)]. The increase of PAI-1 between time180and time240after HC was higher in obese women (+25%) than in controls (+12%) ( P < 0.05), whereas no differential effect between groups was observed for free fatty acids or adiponectin. A moderate hypercortisolism, equivalent to that induced by a mild stress, has more pronounced consequences on insulin sensitivity in abdominally obese women than in controls. These deleterious effects are correlated with the amount of visceral fat.
Consomic strategies to localize genomic regions related to vascular reactivity in the Dahl salt-sensitive rat
Authors: Kunert Mary Pat , Drenjancevic-Peric Ines , Dwinell Melinda R. , Lombard Julian H. , Cowley Allen W. , Greene Andrew S. , Kwitek Anne E. , Jacob Howard J.
Published: June 2006

Chromosomal substitution strains afford the opportunity to discover regions of the rat genome that contain genes related to cardiovascular traits with the long-range goal of linking these genes to physiological function. PhysGen (Programs for Genomic Applications) created a consomic panel of rats derived from the introgression of a single chromosome (≥95% of the BN chromosome, one at a time) of the Brown Norway (BN/NHsdMcwi) rat onto the homogeneous genetic background of the Dahl salt-sensitive rat (SS/JrHsdMcwi). For 3 wk before the experiment, the rats were maintained on a low-salt diet (0.4% NaCl). The dose response of aortic rings from each strain of rat to phenylephrine, acetylcholine, sodium nitroprusside, and three different levels of tissue bath hypoxia (10, 5, and 0% O2) was measured and compared with the parental SS rat. To maximize the possibility that differences among the strains would become apparent, each strain of rat including the parental SS and BN was also studied after being maintained on a high-salt diet (4.0% NaCl) for 3 wk. If the response of the aortic ring from a consomic strain to these vasoactive substances was different from that of the SS parental strain, it was concluded that the introgressed chromosome contained a gene or genes that contributed to that difference. Because the BN chromosome is removed from its native background and the SS rat loses a native chromosome, it is also necessary to consider the contribution of changes in gene-to-gene interaction.
Joint National Cancer Institute-Food and Drug Administration Workshop on Research Strategies, Study Designs, and Statistical Approaches to Biomarker Validation for Cancer Diagnosis and Detection
Authors: Maruvada Padma , Srivastava Sudhir
Published: June 2006

Cancer remains the second leading cause of death in the United States, in spite of tremendous advances made in therapeutic and diagnostic strategies. Successful cancer treatment depends on improved methods to detect cancers at early stages when they can be treated more effectively. Biomarkers for early detection of cancer enable screening of asymptomatic populations and thus play a critical role in cancer diagnosis. However, the approaches for validating biomarkers have yet to be addressed clearly. In an effort to delineate the ambiguities related to biomarker validation and related statistical considerations, the National Cancer Institute, in collaboration with the Food and Drug Administration, conducted a workshop in July 2004 entitled “Research Strategies, Study Designs, and Statistical Approaches to Biomarker Validation for Cancer Diagnosis and Detection.” The main objective of this workshop was to review basic considerations underpinning the study designs, statistical methodologies, and novel approaches necessary to rapidly advance the clinical application of cancer biomarkers. The current commentary describes various aspects of statistical considerations and study designs for cancer biomarker validation discussed in this workshop. (Cancer Epidemiol Biomarkers Prev 2006;15(6):1078–82)
Gender Differences in Determinants of Smoking Initiation and Persistence in California Twins
Authors: Hamilton Ann S. , Lessov-Schlaggar Christina N. , Cockburn Myles G. , Unger Jennifer B. , Cozen Wendy , Mack Thomas M.
Published: June 2006

Objective: To determine the effects of genetic versus environmental influences on smoking initiation (SI) and smoking persistence (SP).

Methods: Native California twins (32,359 pairs), who completed a questionnaire in 1992 or 1998 to 2001, were studied. Standard epidemiologic and genetic analyses were conducted using multiple logistic regression and biometric models to determine factors related to smoking phenotype.

Results: The strongest influence on SI was having a co-twin who ever smoked; the adjusted odds ratio was 9.7 [95% confidence limits (CL), 8.8-10.6] among monozygotic twins and 5.7 (95% CL, 5.2-6.2) among dizygotic like-sex pairs. The risk of SP was also increased if the co-twin currently smoked [adjusted odds ratios, 3.5 (95% CL, 3.0-4.1) for monozygotic twins and 2.3 (95% CL, 2.0-2.7) for like-sex dizygotic pairs]. The proportions of variance due to genetic effects, shared environment, and individual environment for SI were 31.6% (24.2-39.1), 47.5% (41.1-53.7), and 20.9% (18.8-23.1) for females, and 71.2% (66.7-75.4), 12.0% (8.7-15.7), and 16.7% (15.0-18.7) for males. For SP, estimates were identical by gender: 54.6% (43.6-65.5), 8.6% (0-17.1), and 36.8% (32.9-40.9). Modification of SI by closeness between twins was found, but little difference was seen for SP by closeness, birth cohort, or age.

Conclusions: Gender differences in the pattern of genetic and environmental determinants of SI indicate that gender-specific approaches may be needed for smoking prevention efforts. Modification of genetic effects by closeness between twins and birth cohort suggests that environmental interventions could reduce a heritable propensity to smoke. However, the apparently heritable tendency to continue smoking is unaffected by gender, age, birth cohort, or closeness between twins. (Cancer Epidemiol Biomarkers Prev 2006;15(6):1189–97)
Total Fluid Intake and Use of Individual Beverages and Risk of Renal Cell Cancer in Two Large Cohorts
Authors: Lee Jung Eun , Giovannucci Edward , Smith-Warner Stephanie A. , Spiegelman Donna , Willett Walter C. , Curhan Gary C.
Published: June 2006

Moderate alcohol consumption has been inversely associated with risk of renal cell cancer in recent prospective studies, and increased total fluid intake has been hypothesized to be a possible mechanism. We prospectively examined the associations between total fluid and beverage intakes and risk of renal cell cancer. Among 88,759 women followed for 20 years in the Nurses' Health Study, and 47,828 men followed for 14 years in the Health Professionals Follow-up Study, we documented 248 incident cases of renal cell cancer. We assessed consumption of beverages every 2 to 4 years using a validated semiquantitative food frequency questionnaire, and total fluid intake was derived from the frequency of consumption of 18 to 22 beverage items. Cox proportional hazards regression was used to estimate study-specific multivariate relative risks (RR), which were pooled using a random-effects model. We found no association between total fluid intake and risk of renal cell cancer; the pooled multivariate RR for the highest quartile versus the lowest was 0.99 (95% confidence interval, 0.63-1.55; P, test for trend = 0.78). Alcohol intake was marginally inversely associated with renal cell cancer risk; compared with nondrinkers, the pooled multivariate RR for ≥15 g/d was 0.66 (95% confidence interval, 0.43-1.00; P, test for trend = 0.07). We did not find clear associations between intakes of coffee, tea, milk, juice, soda, punch, and water and risk of renal cell cancer. Our data suggest an inverse association between alcohol intake and risk of renal cell cancer, but do not support the hypothesis that greater total fluid intake reduces the risk of renal cell cancer. (Cancer Epidemiol Biomarkers Prev 2006;15(6):1204–11)
Effects of Raloxifene on Circulating Prolactin and Estradiol Levels in Premenopausal Women at High Risk for Developing Breast Cancer
Authors: Faupel-Badger Jessica M. , Prindiville Sheila A. , Venzon David , Vonderhaar Barbara K. , Zujewski Jo Anne , Eng-Wong Jennifer
Published: June 2006

Background: Prolactin is a peptide hormone necessary for normal breast development that may contribute to breast tumorigenesis. Estrogen is a significant positive regulator of prolactin synthesis; therefore, raloxifene, a selective estrogen receptor modulator under study as a breast cancer prevention agent, may modulate both estradiol and prolactin levels by inhibiting estradiol from binding to its receptor.

Methods: Premenopausal women at increased risk for invasive breast cancer participated in a pilot chemoprevention trial and were given 60 mg raloxifene daily for 24 months. Fasting serum samples collected at baseline and after 12 months on drug were used to measure circulating prolactin, estradiol, and sex hormone binding globulin (SHBG) levels.

Results: Of the 27 subjects who completed 12 months of raloxifene, 23 had paired prolactin samples, and 20 had paired estradiol and SHBG samples. Prolactin levels did not significantly change with raloxifene treatment, but SHBG levels increased (mean change = 7.3 nmol/L; P = 0.0001; 95% confidence interval, 3.9-10.7). Estradiol (mean change = 42 pg/mL; P = 0.048; 95% confidence interval, 1-84 pg/mL) levels were elevated when comparing 15 of the 20 women with paired estradiol measurements who also had both of these samples taken during the early follicular phase of the menstrual cycle.

Conclusions: This report is the first to examine the long-term effects of raloxifene on prolactin, estradiol, and SHBG levels in premenopausal women who are also at increased risk for developing invasive breast cancer. Raloxifene had no significant effect on prolactin levels but did increase estradiol and SHBG measurements. (Cancer Epidemiol Biomarkers Prev 2006;15(6):1153–8)
Prevalence of Chronic Atrophic Gastritis in Different Parts of the World
Authors: Weck Melanie Nicole , Brenner Hermann
Published: June 2006

Chronic atrophic gastritis (CAG) is a well-established precursor of intestinal gastric cancer, but epidemiologic data about its occurrence are sparse. We provide an overview on studies that examined the prevalence of CAG in different parts of the world. Articles containing data about the prevalence of chronic atrophic gastritis in unselected population samples and published until November 2005 were identified by searching the MEDLINE database. Furthermore, the references in the identified publications were screened for additional suitable studies. Studies comprising at least 50 subjects were included. Forty-one studies providing data on the prevalence of CAG in unselected population samples could be identified. CAG was determined by gastroscopy in 15 studies and by pepsinogen serum levels in 26 studies. Although results are difficult to compare due to the various definitions of CAG used, a strong increase with age, the lack of major gender differences, and strong variations between populations and population groups (in particular, relatively high rates in certain Asian populations) could be observed quite consistently. We conclude that CAG is relatively common among older adults in different parts of the world, but large variations exist. Large-scale international comparative studies with standardized methodology to determine CAG are needed to provide a coherent picture of the epidemiology of CAG in various populations. Noninvasive measurements of CAG by pepsinogen levels may be particularly suited for that purpose. (Cancer Epidemiol Biomarkers Prev 2006;15(6):1083–94)
Plasma Enterolignans Are Associated with Lower Colorectal Adenoma Risk
Authors: Kuijsten Anneleen , Arts Ilja C.W. , Hollman Peter C.H. , van't Veer Pieter , Kampman Ellen
Published: June 2006

Lignans are biphenolic compounds that occur in foods of plant origin such as whole grains, seeds, fruits and vegetables, and beverages, such as coffee and tea. Plant lignans are converted by intestinal bacteria into the enterolignans, enterodiol and enterolactone. Enterolignans possess several biological activities, whereby they may influence carcinogenesis. We studied the associations between plasma enterolignans and the risk of colorectal adenomas in a Dutch case-control study. Colorectal adenomas are considered to be precursors of colorectal cancer. Cases (n = 532) with at least one histologically confirmed colorectal adenoma and controls (n = 503) with no history of any type of adenoma were included. Plasma enterodiol and enterolactone concentrations were measured by liquid chromatography with tandem mass spectrometry. Associations were stronger for incident than for prevalent cases. When only incident cases (n = 262) were included, high compared to low plasma concentrations of enterodiol were associated with a reduction in colorectal adenoma risk after adjustment for confounding variables. Enterodiol odds ratios (95% confidence intervals) were 1.00, 0.69 (0.42-1.13), 0.60 (0.37-0.99), and 0.53 (0.32-0.88) with a significant trend (P = 0.01) through the quartiles. Although enterolactone plasma concentrations were 10-fold higher, enterolactone's reduction in risk was not statistically significant (P for trend = 0.09). Use of oral antibiotic therapy could decrease the plasma concentrations of enterolactone. Exclusion of antibiotic users resulted in similar odds ratios for both enterolignans, but the association for enterolactone became somewhat stronger (P = 0.05 versus P = 0.09). We observed a substantial reduction in colorectal adenoma risk among subjects with high plasma concentrations of enterolignans, in particular, enterodiol. These findings could be important in the prevention of colorectal adenomas. (Cancer Epidemiol Biomarkers Prev 2006;15(6):1132–6)
A Sensitive Method to Quantify Human Long DNA in Stool: Relevance to Colorectal Cancer Screening
Authors: Zou Hongzhi , Harrington Jonathan J. , Klatt Kristie K. , Ahlquist David A.
Published: June 2006

Human long DNA in stool may reflect nonapoptotic exfoliation and has been used as a colorectal cancer (CRC) marker. Targeting human-specific Alu repeats represents a logical but untested approach. A real-time Alu PCR assay was developed for quantifying long human DNA in stool and evaluated in this study. The accuracy and reproducibility of this assay and the stability of long DNA during room temperature fecal storage were assessed using selected patient stools and stools added to human DNA. Thereafter, long DNA levels were determined in blinded fashion from 18 CRC patients and 20 colonoscopically normal controls. Reproducibility of real-time Alu PCR for quantifying fecal long DNA was high (r2 = 0.99; P < 0.01). Long DNA levels in nonbuffered stools stored at room temperature fell a median of 75% by 1 day and 81% by 3 days. An EDTA buffer preserved DNA integrity during such storage. Human long DNA was quantifiable in all stools but was significantly higher in stools from CRC patients than from normal controls (P < 0.05). At a specificity of 100%, the sensitivity of long DNA for CRC was 44%. Results indicate that real-time Alu PCR is a simple method to sensitively quantify long human DNA in stool. This study shows that not all CRCs are associated with increased fecal levels of long DNA. Long DNA degrades with fecal storage, and measures to stabilize this analyte must be considered for optimal use of this marker. (Cancer Epidemiol Biomarkers Prev 2006;15(6):1115–9)
Association of Physical Activity with Hormone Receptor Status: The Shanghai Breast Cancer Study
Authors: Adams Swann Arp , Matthews Charles E. , Hebert James R. , Moore Charity G. , Cunningham Joan E. , Shu Xiou-Oi , Fulton Jeanette , Gao Yutang , Zheng Wei
Published: June 2006

Evidence exists that breast tumors differing by estrogen receptor (ER) and progesterone receptor (PR) status may be phenotypically distinct diseases resulting from dissimilar etiologic processes. Few studies have attempted to examine the association of physical activity with breast cancer subtype. Such research may prove instructive into the biological mechanisms of activity. Consequently, this investigation was designed to assess the relationship between physical activity and hormone receptor-defined breast cancers in a population of Asian women in which the distribution of receptor types differed from traditional Western populations. Participants, ages 25 to 64 years, were recruited into this population-based, case-control study of breast cancer conducted in Shanghai, China from August 1996 to March 1998. Histologically confirmed breast cancer cases with available receptor status information (n = 1001) and age frequency-matched controls (n = 1,556) completed in-person interviews. Polytomous logistic regression was used to model the association between measures of activity with each breast cancer subtype (ER+/PR+, ER−/PR−, ER+/PR−, and ER−/PR+) using the control population as the reference group. Exercise in both adolescence and the last 10 years was associated with a decreased risk of both receptor-positive (ER+/PR+) and receptor-negative (ER−/PR−) breast cancers in both premenopausal and postmenopausal women (odds ratios, 0.44 and 0.51 and 0.43 and 0.21, respectively). Sweating during exercise within the last 10 years was also associated with decreased risk for receptor-positive and receptor-negative breast cancers among postmenopausal women (odds ratios, 0.58 and 0.28, respectively). These findings suggest that physical activity may reduce breast cancer risk through both hormonal and nonhormonal pathways. (Cancer Epidemiol Biomarkers Prev 2006;15(6):1170–8)
Body Size, Physical Activity, and Risk of Hodgkin's Lymphoma in Women
Authors: Keegan Theresa H.M. , Glaser Sally L. , Clarke Christina A. , Dorfman Ronald F. , Mann Risa B. , DiGiuseppe Joseph A. , Chang Ellen T. , Ambinder Richard F.
Published: June 2006

Few studies have examined the associations of body size and physical activity with the development of Hodgkin's lymphoma (HL) in women. In data from a population-based case-control study in women ages 19 to 79 years, we assessed the relation of self-report height, weight, body mass index (BMI), and strenuous physical activity to HL risk in 312 cases with diagnostic re-review and 325 random-digit dialed controls using logistic regression. Analyses were stratified by age group and tumor cell presence of EBV. After adjustment for social class measures, taller childhood and adult height were associated with higher HL risk. In women ages 19 to 44 years, HL risk was elevated for higher, but healthy, BMI values, whereas in women ages 45 to 79 years, associations with BMI were inverse. The odds of developing HL were lower with participation (versus nonparticipation) in strenuous physical activity in the past year [odds ratio (OR), 0.58; 95% confidence interval (95% CI), 0.39-0.87 in women 19-44 years; OR, 0.45; 95% CI, 0.19-1.06 in women 45-79 years] and throughout adult life, and with sports team membership (versus nonmembership) in high school and/or at ages 18 to 22 years. Results were similar in cases (n = 269) with and without tumor-cell EBV compared with controls, although the inverse association with physical activity was somewhat stronger for women with EBV-positive disease. These findings show that in women, body size and strenuous physical activity, both modifiable characteristics, are associated with HL risk in adult life possibly through immunologic, infectious, or genetic mechanisms. (Cancer Epidemiol Biomarkers Prev 2006;15(6):1095–101)