bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of androgenic-anabolic steroids on apolipoproteins and lipoprotein (a)
Authors: Hartgens F , Rietjens G , Keizer H A , Kuipers H , Wolffenbuttel B H R
Published: May 2004

Objectives:To investigate the effects of two different regimens of androgenic-anabolic steroid (AAS) administration on serum lipid and lipoproteins, and recovery of these variables after drug cessation, as indicators of the risk for cardiovascular disease in healthy male strength athletes.

Methods:In a non-blinded study (study 1) serum lipoproteins and lipids were assessed in 19 subjects who self administered AASs for eight or 14 weeks, and in 16 non-using volunteers. In a randomised double blind, placebo controlled design, the effects of intramuscular administration of nandrolone decanoate (200 mg/week) for eight weeks on the same variables in 16 bodybuilders were studied (study 2). Fasting serum concentrations of total cholesterol, triglycerides, HDL-cholesterol (HDL-C), HDL2-cholesterol (HDL2-C), HDL3-cholesterol (HDL3-C), apolipoprotein A1 (Apo-A1), apolipoprotein B (Apo-B), and lipoprotein (a) (Lp(a)) were determined.

Results:In study 1 AAS administration led to decreases in serum concentrations of HDL-C (from 1.08 (0.30) to 0.43 (0.22) mmol/l), HDL2-C (from 0.21 (0.18) to 0.05 (0.03) mmol/l), HDL3-C (from 0.87 (0.24) to 0.40 (0.20) mmol/l, and Apo-A1 (from 1.41 (0.27) to 0.71 (0.34) g/l), whereas Apo-B increased from 0.96 (0.13) to 1.32 (0.28) g/l. Serum Lp(a) declined from 189 (315) to 32 (63) U/l. Total cholesterol and triglycerides did not change significantly. Alterations after eight and 14 weeks of AAS administration were comparable. No changes occurred in the controls. Six weeks after AAS cessation, serum HDL-C, HDL2-C, Apo-A1, Apo-B, and Lp(a) had still not returned to baseline concentrations. Administration of AAS for 14 weeks was associated with slower recovery to pretreatment concentrations than administration for eight weeks. In study 2, nandrolone decanoate did not influence serum triglycerides, total cholesterol, HDL-C, HDL2-C, HDL3-C, Apo-A1, and Apo-B concentrations after four and eight weeks of intervention, nor six weeks after withdrawal. However, Lp(a) concentrations decreased significantly from 103 (68) to 65 (44) U/l in the nandrolone decanoate group, and in the placebo group a smaller reduction from 245 (245) to 201 (194) U/l was observed. Six weeks after the intervention period, Lp(a) concentrations had returned to baseline values in both groups.

Conclusions:Self administration of several AASs simultaneously for eight or 14 weeks produces comparable profound unfavourable effects on lipids and lipoproteins, leading to an increased atherogenic lipid profile, despite a beneficial effect on Lp(a) concentration. The changes persist after AAS withdrawal, and normalisation depends on the duration of the drug abuse. Eight weeks of administration of nandrolone decanoate does not affect lipid and lipoprotein concentrations, although it may selectively reduce Lp(a) concentrations. The effect of this on atherogenesis remains to be established.
Intramuscular haemangioma of the thigh in a basketball player
Authors: Brown R A , Crichton K , Malouf G M
Published: May 2004

Haemangioma is a common benign soft tissue tumour. Intramuscular haemangiomas may present as a perceived sporting injury. Magnetic resonance imaging is the investigation of choice. Intramuscular haemangioma should be considered in the differential diagnosis of unexplained pain and swelling in a muscle.
QUANTIZATION OF BOSONIC STRING MODEL IN (26+2)-DIMENSIONAL SPACE–TIME
Authors: TSUKIOKA TAKUYA , WATABIKI YOSHIYUKI
Published: May 2004

We investigate the quantization of the bosonic string model which has a local U (1)V× U (1)Agauge invariance as well as the general coordinate and Weyl invariance on the world-sheet. The model is quantized by Lagrangian and Hamiltonian BRST formulations á la Batalin, Fradkin and Vilkovisky and noncovariant light-cone gauge formulation. Upon the quantization the model turns out to be formulated consistently in (26+2)-dimensional background space–time involving two time-like coordinates.
Molecular Pathology of the MEN1 Gene
Authors: AGARWAL SUNITA K. , LEE BURNS A , SUKHODOLETS KAREN E. , KENNEDY PATRICIA A. , OBUNGU VICTOR H. , HICKMAN ALISON B. , MULLENDORE MICHAEL E. , WHITTEN IRA , SKARULIS MONICA C. , SIMONDS WILLIAM F. , MATEO CARMEN , CRABTREE JUDY S. , SCACHERI PETER C. , JI YOUNGMI , NOVOTNY ELIZABETH A. , GARRETT‐BEAL LISA , WARD JERROLD M. , LIBUTTI STEVEN K. , RICHARD ALEXANDER H , CERRATO ANIELLO , PARISI MICHAEL J. , SANTA ANNA‐A SONIA , OLIVER BRIAN , CHANDRASEKHARAPPA SETTARA C. , COLLINS FRANCIS S. , SPIEGEL ALLEN M. , MARX STEPHEN J.
Published: May 2004

Abstract: Multiple endocrine neoplasia type 1 (MEN1), among all syndromes, causes tumors in the highest number of tissue types. Most of the tumors are hormone producing (e.g., parathyroid, enteropancreatic endocrine, anterior pituitary) but some are not (e.g., angiofibroma). MEN1 tumors are multiple for organ type, for regions of a discontinuous organ, and for subregions of a continuous organ. Cancer contributes to late mortality; there is no effective prevention or cure for MEN1 cancers. Morbidities are more frequent from benign than malignant tumor, and both are indicators for screening. Onset age is usually earlier in a tumor type of MEN1 than of nonhereditary cases. Broad trends contrast with those in nonneoplastic excess of hormones (e.g., persistent hyperinsulinemic hypoglycemia of infancy). Most germline or somatic mutations in the MEN1 gene predict truncation or absence of encoded menin. Similarly, 11q13 loss of heterozygosity in tumors predicts inactivation of the other MEN1 copy. MEN1 somatic mutation is prevalent in nonhereditary, MEN1‐like tumor types. Compiled germline and somatic mutations show almost no genotype/phenotype relation. Normal menin is 67 kDa, widespread, and mainly nuclear. It may partner with junD, NF‐kB, PEM, SMAD3, RPA2, FANCD2, NM23β, nonmuscle myosin heavy chain II‐A, GFAP, and/or vimentin. These partners have not clarified menin's pathways in normal or tumor tissues. Animal models have opened approaches to menin pathways. Local overexpression of menin in Drosophila reveals its interaction with the jun‐kinase pathway. The Men1+/− mouse has robust MEN1; its most important difference from human MEN1 is marked hyperplasia of pancreatic islets, a tumor precursor stage.
Molecular Genetics of Gastroenteropancreatic Endocrine Tumors
Authors: PERREN AUREL , KOMMINOTH PAUL , HEITZ PHILIPP U.
Published: May 2004

Abstract: To elucidate the molecular background of sporadic gastroenteropancreatic endocrine tumors, several investigations into chromosomal alterations and allelic imbalances have identified several chromosomal regions of interest. These regions might harbor candidate genes important in tumor development and progression. However, only a small number of genes have been thoroughly analyzed, and only very few were shown to be altered in a substantial subset of tumors. Therefore, we are far from understanding the molecular mechanisms of tumor initiation and progression in gastroenteropancreatic endocrine tumors, although some “molecular patterns” are currently emerging. In this review, chromosomal alterations, that is, allelic losses and gene mutations, identified in gastroenteropancreatic endocrine tumors are briefly summarized. Molecular differences among various subtypes of gastroenteropancreatic endocrine tumors are highlighted in view of their role as indicators of separate genetic pathways.
Cyclin D1 in Human Neuroendocrine: Tumorigenesis
Authors: CHUNG DANIEL C.
Published: May 2004

Abstract: Human neuroendocrine tumors exhibit unique biological properties, and defining the molecular genetic alterations that underlie these distinctive features remains an important challenge. In addition to the MEN1 tumor suppressor gene, the cyclin D1 oncogene has demonstrated a role in the pathogenesis of parathyroid and gastroenteropancreatic neuroendocrine tumors. Up‐regulation of cyclin D1 is observed early in tumor formation, implying a possible role in tumor initiation. Overexpression of cyclin D1 in the parathyroid glands of mice resulted in the tandem regulation of cellular proliferation and hormonal secretion, a feature intrinsic to neuroendocrine tumors.
Analysis of Molecular Pathways in Neuroendocrine Cancers of the Gastroenteropancreatic System
Authors: ARNOLD CHRISTIAN N. , SOSNOWSKI ANDREA , BLUM HUBERT E.
Published: May 2004

Abstract: Neuroendocrine gastroenteropancreatic (GEP) tumors are rare and present with variable clinical syndromes. So far, there are no detailed studies concerning the molecular pathogenesis of sporadic GEP tumors. In our study, GEP tumors from 29 patients were assessed for microsatellite instability, aberrant promoter methylation, and LOH of various tumor suppressor genes. All tumors were microsatellite stable. One tumor showed LOH close to the APC locus, one tumor had an allelic loss near the hMLH1 gene, and one tumor showed hypermethylation of the hMLH1 promoter. Interestingly, none of the tumors was aberrantly methylated at the p16 promoter. However, 13 of 20 successfully amplified tumors (65%) were hypermethylated at the APC promoter. Of the hypermethylated tumors, none showed LOH of either the hMLH1 or the APC gene. The current study is the first report demonstrating that aberrant methylation of the APC promoter is strongly involved in the molecular tumorigenesis of neuroendocrine GEP tumors. MSI does not seem to be involved in the pathogenesis of these cancers. Further studies are required to investigate the role of hypermethylation in neuroendocrine GEP tumors and to further elucidate the role of the APC pathway in these tumors.
GOT1 Xenografted to Nude Mice: A Unique Model for in Vivo Studies on SSTR‐Mediated Radiation Therapy of Carcinoid Tumors
Authors: NILSSON OLA , KÖLBY LARS , BERNHARDT PETER , FORSSELL‐ARONSSON EVA , JOHANSON VIKTOR , AHLMAN HÅKAN
Published: May 2004

Abstract: Malignant carcinoid tumors express high numbers of somatostatin receptors. Radiation therapy using labeled somatostatin analogs is a novel treatment modality for these tumors. We have analyzed the biokinetics and therapeutic effect of radiolabeled somatostatin analog on a human midgut carcinoid grafted to nude mice. A transplantable human midgut carcinoid (GOT1) was grafted to the back of nude mice. Tumor‐bearing mice were injected with 111In‐DTPA‐D‐Phe1‐octreotide, followed by measurement of 111In activity concentration ratios in tumor tissues. Tumor‐bearing mice were also injected with 177Lu‐DOTA‐Tyr3‐octreotate and followed for 7 days. The concentration of 111In‐DTPA‐D‐Phe1‐octreotide in tumor tissues was very high 4 hours postinjection with 0.4–13% of injected activity per gram. Injection of 30–120 MBq 177Lu‐DOTA‐Tyr3‐octreotate reduced tumor volume to 7–14% of the original tumor volume 7 days postinjection. Microscopic analysis of treated tumors revealed widespread areas of tumor cell necrosis and fibrosis. It was found that grafted GOT1 cells to nude mice represent an authentic model for studying human midgut carcinoids. Radiolabeled somatostatin analogs have a high selectivity for tumor tissue and can induce tumor cell necrosis. Radiotherapy of carcinoid tumors with 177Lu‐DOTA‐Tyr3‐octreotate appears to be a promising treatment modality for either palliative treatment or completion therapy after attempted surgical cure.
Using a Mixed Integer Programming Tool for Solving the 0–1 Quadratic Knapsack Problem
Authors: Billionnet Alain , Soutif Éric
Published: May 2004

In this paper we will consider the 0–1 quadratic knapsack problem (QKP). Our purpose is to show that using a linear reformulation of this problem and a standard mixed integer programming tool, it is possible to solve the QKP efficiently in terms of computation time and the size of problems considered, in comparison to existing methods. Considering a problem involving n variables, the linearization technique we propose has the advantage of adding only (n – 1) real variables and 2(n – 1) constraints. We present extensive computational results on randomly generated instances and on structured problems coming from applications. For example, the method allows us to solve randomly generated QKP instances exactly with up to 140 variables.
The Continuous Assignment Problem and Its Application to Preemptive and Non-Preemptive Scheduling with Irregular Cost Functions
Authors: Sourd Francis
Published: May 2004

This paper focuses on the continuous assignment problem with the eventual aim to solve scheduling problems with irregular cost functions. It consists of partitioning a region of Rd into subregions of prescribed volumes so that the total cost is minimized. The dual problem of the continuous assignment problem is an unconstrained maximization of a non-smooth concave function. The preemptive variant of the scheduling problem with irregular cost functions corresponds to the one-dimensional continuous assignment problem and a lower bound for the non-preemptive variant can be derived. It is computationally tested in a branch-and-bound algorithm.
Implementing an LU Factorization for the Embedded Network Simplex Algorithm
Authors: McBride Richard D. , Mamer John W.
Published: May 2004

This paper presents an LU factorization specialized for embedded network simplex algorithms. Specializing the LU factorization in this fashion poses a challenge as the embedded network algorithm uses a very compressed working basis inverse. Using publicly available test problems, we demonstrate the impact of this factorization on the EMNET implementation of the embedded network simplex algorithm. We also compare the impact of the LU factorization when coupled with recent advances in starting, pricing, and basis reduction that have already been implemented in EMNET. We demonstrate that this LU factorization is a vital component of EMNET and offers significant performance improvement for virtually all EMNET configurations. To place our results in context, we compare EMNET’s performance with CPLEX.
Strategies to Reduce Toxicities and Improve Outcomes in Renal Transplant Recipients
Authors: Lo Agnes , Alloway Rita R.
Published: May 2004

Ongoing improvements in immunosuppression and posttransplantation care have dramatically improved patient and graft outcomes after transplantation. The frequency of graft loss due to acute rejection has declined considerably as a result of the availability of a variety of more potent immunosuppressive agents and probably also because of refined clinical care and follow‐up. Complications of long‐term administration of corticosteroids (steroids) and calcineurin inhibitors, however, have become increasingly apparent as patients live longer with their transplant, and attention is shifting to long‐term issues. Use of both steroids and calcineurin inhibitors is associated with metabolic toxicities such as hypertension, hyperlipidemia, diabetes, bone loss, and cataracts. These contribute to posttransplantation morbidity and may negatively affect patient and allograft survival. A variety of troublesome cosmetic side effects, such as hirsutism, gingival hyperplasia, alopecia, obesity, and cushingoid appearance, also are associated with these drugs. These effects can detract from patient self‐esteem and compliance with the immunosuppressive regimen. In the past 2 decades, the introduction of second‐generation immunosuppressive drugs, such as tacrolimus, mycophenolate mofetil, sirolimus, and anti‐interleukin‐2 receptor monoclonal antibodies, has provided some alternatives to classic immunosuppressant choices. Patients experiencing undesirable adverse events now can be converted to another immunosuppressive regimen that ultimately will improve graft and patient survival rates and improve quality of life after transplantation.
Etomidate for Procedural Sedation in the Emergency Department
Authors: Keim Samuel M. , Erstad Brian L. , Sakles John C. , Davis Virgil
Published: May 2004

Study Objective. To review our experience with etomidate in nonintubated patients in the emergency department.

Design. A 2‐year retrospective chart review of consecutive patients receiving etomidate for sedation.

Setting. Emergency department of a university‐based teaching hospital.

Patients. Forty‐eight patients who underwent painful procedures in the emergency department.

Measurements and Main Results. Demographics, dosing information, recovery times, and adverse events were abstracted using a standardized data collection form. Forty‐eight nonintubated patients were sedated with etomidate. Mean age was 34 years (range 6–80 yrs); 38 were men and 10 women; two were children. The mean initial dose of etomidate was 13 mg. Adverse events occurred in 11 (21%) patients. None sustained any substantial morbidity as indicated by need for intubation, prolonged emergency department stay, or hospital admission.

Conclusion. Although controversial, etomidate holds promise as a potent sedative agent for patients undergoing painful procedures in the emergency department. A large prospective evaluation is needed to document the performance and complications of this agent.
Managing Anemia in the Critically Ill Patient
Authors: Rudis Maria I. , Jacobi Judith , Hassan Erkan , Dasta Joseph F.
Published: May 2004

Anemia of critical illness is a multifactorial condition caused by phlebotomy, ongoing blood loss, and inadequate production of red blood cells. It occurs early in the course of critical illness. Although red blood cell transfusion is the treatment of choice for immediate management of anemia in the intensive care unit, controversy surrounds the most appropriate hemoglobin concentration or hematocrit “trigger.” Therapeutic options, including blood‐conservation tools, minimization of phlebotomy, erythropoietic agents, and investigational oxygen‐carrying agents, may be alternatives to red blood cell transfusions in critically ill patients with anemia. Patient selection for erythropoietic agents will depend on further work dealing with outcomes and the total cost of care in managing the anemia of critical illness.
Key Articles and Guidelines in Pharmacotherapeutic Management of Arrhythmias
Authors: Cheng Judy W. M. , Frank Lori , Garrett Stephanie D. , Lu Yun , Sanoski Cynthia A. , White C. Michael
Published: May 2004

Clinical studies are among the most important literature published in the area of cardiovascular pharmacotherapy and are the basis of many of the standards of practice today. We compiled a list of these clinical trials, as well as well‐written, up‐to‐date review articles and important treatment guidelines, that focus on pharmacotherapeutic management of arrhythmias. This list should be useful not only to practitioners and trainees in cardiovascular pharmacotherapy, but also to other clinicians as an update.
Donepezil for Alcohol‐Related Dementia: A Case Report
Authors: Kim Kye Y. , Ke Victoria , Adkins Laurie M.
Published: May 2004

A 75‐year old man with a 40‐year history of alcoholism was admitted to the hospital for intoxication and inability to care for himself. He had been admitted frequently in the past for detoxification and rehabilitation. The patient had no family history of Alzheimer's disease, no history of head injury, and single‐photon emission computed tomography showed no typical findings of Alzheimer's disease. His cognitive function was impaired. He was treated with donepezil for alcohol‐related dementia, and 3 months later, his cognitive function had improved. More research is needed to confirm donepezil's role in treating alcohol‐related dementia.
Percutaneous revascularization of the common femoral artery for limb ischemia
Authors: Silva Jose A. , White Christopher J. , Quintana Hugo , Collins Tyrone J. , Jenkins J. Stephen , Ramee Stephen R.
Published: May 2004

We performed percutaneous transluminal intervention in 20 consecutive patients (21 limbs) with common femoral artery (CFA) lesions causing symptomatic limb ischemia. In 12 limbs, concurrent additional percutaneous intervention proximal or distal to the target CFA lesion was performed. Angiographic success was obtained in 100%, with procedural success (angiographic success without a major in‐hospital complications) in 90% and clinical success (procedural success and in‐hospital improvement by at least one Fontaine functional class) in 81% of the limbs. The in‐hospital Fontaine class improved by at least one functional class in 17 of 19 patients (89%), and the overall in‐hospital event‐free survival was 90% (18 of 20 patients). At follow‐up (11.4 ± 6 months), the overall event‐free survival was 90% (18 of 20 patients) and 17 of 19 patients (89%) continue to show improvement by at least one functional (Fontaine) class. Percutaneous intervention of the CFA can be performed with a rate of high technical success and a low complication rate. It provides excellent clinical results at mid‐term follow‐up and appears to be a reasonable alternative to surgical therapy in patients at high risk for surgery. Catheter Cardiovasc Interv 2004;62:230–233. © 2004 Wiley‐Liss, Inc.
Use of IIb/IIIa inhibitors in patients with in‐stent restenosis treated with intracoronary γ‐radiation: Integrilin WRIST
Authors: Waksman Ron , Ajani Andrew E. , Gruberg Luis , Pinnow Ellen , GebreEyesus Afework , Deible Regina , Satler Lowell F. , Pichard Augusto D. , Torguson Rebecca , Kent Kenneth M. , Suddath William , Lindsay Joseph
Published: May 2004

The Integrilin Washington Radiation for In‐Stent Restenosis Trial (WRIST) aimed to study the impact of IIb/IIIa inhibitors as adjunct therapy to intracoronary radiation therapy (IRT) for patients with in‐stent restenosis (ISR). The impact of GP IIb/IIIa inhibitor (eptifibatide) as adjunct therapy to vascular brachytherapy using 192Ir emitter was examined in patients with in‐stent restenosis. In the study, 150 patients were assigned to eptifibatide (Integrilin) and 150 patients to heparin only. Clinical composite endpoints at 30 days were similar between the patients treated with and without eptifibatide (4.7% vs. 4.0%; P = 0.78). There was a similarity in the non‐Q‐wave myocardial infarction (MI) rates between the eptifibatide and the control group. Major bleeding was similar in patients treated with and without eptifibatide. Overall, the use of eptifibatide as adjunct therapy for patients with ISR that are treated with IRT did not impact the clinical outcome at 30 days. Catheter Cardiovasc Interv 2004;62:162–166. © 2004 Wiley‐Liss, Inc.
Contribution to the stability analysis of the dewetted Bridgman growth under microgravity conditions
Authors: Bizet L. , Duffar T.
Published: May 2004

Experimental observations show that the gap between the sample and the crucible, commonly obtained after solidification in microgravity, is remarkably stable. With the aim to understand the reason of this stability, the dewetting phenomenon is studied by Lyapunov's method. After a short review of the existing mechanisms leading to dewetting, the open smooth crucible configuration is chosen as the most representative. The analytical stability analysis, taking into account geometrical and thermal effects, performed under some boundary heat transfer approximations, shows that, in most cases, the dewetting process is intrinsically stable. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the effects of Ga3+ and La3+ ions in MgCu ferrite: Humidity‐sensitive electrical conduction
Authors: Rezlescu N. , Rezlescu E. , Sava C.‐L. , Tudorache F. , Popa P. D.
Published: May 2004

Pure and gallium or lanthanum substituted MgCu ferrites, Mg0.5Cu0.5Fe2‐xMxO4 (with x = 0 or 0.2 and M = La or Ga) have been prepared by solid state reaction. Sintering experiments were carried out at different temperatures between 900 and 1100°C. The phase composition and lattice parameters were determined by XRD, while the effect of Ga and La substitutions on the granular structure was studied by SEM. Experimental results revealed that the densification behaviour and some physical properties are in close relation with the structural changes of pure ferrite caused by the presence of La and Ga substitutions. The gallium containing compound, Mg0.5Cu0.5Fe1.8Ga0.2O4, is monophasic and contains a great number of pores, whereas the lanthanum containing compound, Mg0.5Cu0.5Fe1.8La0.2O4, is biphasic and exhibits a high density. The humidity characteristics show that the gallium ion enhances the humidity sensitivity of the MgCu ferrite sintered at 1000°C. This interesting effect is promising for the future of the Ga‐substituted MgCu ferrite to be used as sensitive material for fabrication of ceramic humidity sensors. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Development of very‐short‐term load forecasting based on chaos theory
Authors: Kawauchi Seiji , Sugihara Hiroaki , Sasaki Hiroshi
Published: May 2004

It is indispensable to accurately perform short‐term load forecasting of 10 minutes ahead in order to avoid undesirable disturbances in power system operations. The authors have so far developed such a forecasting method based on conventional chaos theory. However, this approach cannot give accurate forecasting results when the loads consecutively exceed the historical maximum or are less than the minimum. Electric furnace loads with steep fluctuations are another factor degrading the forecast accuracy.

This paper presents an improved forecasting method based on chaos theory. In particular, the potential of the Local Fuzzy Reconstruction Method, a variant of the localized reconstruction methods, is fully exploited to realize accurate forecasting as much as possible. To resolve the forecast deterioration due to suddenly changing loads such as by electric furnaces, they are separated from the rest and smoothing operations are carried out afterwards. The separated loads are forecasted independently from the remaining components. Several error correction methods are incorporated to enhance the proposed forecasting method. Furthermore, a consistent measure of obtaining the optimal combination of parameters to be used in the forecasting method is presented. The effectiveness of the proposed methods is verified by using real load data for 1 year. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(2): 55–63, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10322
Novel Bromide PVC‐Based Membrane Sensor Based on Iron(III)‐Salen
Authors: Ganjali Mohammad Reza , Norouzi Parviz , Golmohammadi Mahmood , Rezapour Morteza , Salavati‐Niasari Masoud
Published: May 2004

A novel bromide PVC‐based membrane sensor, based on iron(III)‐salen (IS) as an electroactive material, is successfully developed. The sensor possesses the advantages of low detection limit (6.0×10−6), wide working concentration range (7.0×10−6–1.0×10−1 M), Nernstian behavior (slope of 59.0±0.5 mV per decade), low response time (<15 s), wide working pH range (3–9), and specially, high bromide selectivity over a wide variety of organic and inorganic anions, specially iodide, chloride, and hydroxide ions. The electrode was used in the direct potentiometric determination of hyoscine butylbromide, and as an indicator electrode in potentiometric titration of bromide ions with silver ions.
Facilitated Ion‐Transfer of Sodium Cation by (Anthraquinone‐1‐yloxy) methane‐15‐crown‐5 Across the Water/1,2‐Dichloroethane Microinterface
Authors: Han Xiaojun , Zhang Zhiquan , Dong Shaojun , Wang Erkang
Published: May 2004

The transfer of sodium cation facilitated by (anthraquinone‐1‐yloxy) methane‐15‐crown‐5 (L) has been investigated at the water/1,2‐dichloroethane microinterface supported at the tip of a micropipette. The diffusion coefficient of (anthraquinone‐1‐yloxy) methane‐15‐crown‐5 obtained was (3.42±0.20)×10−6 cm2 s−1. The steady‐state voltammograms were observed for forward and backward scans due to sodium ion transfer facilitated by L with 1 : 1 stoichiometry. The mechanism corresponded to an interfacial complexation (TIC) and interfacial dissociation (TID) process. The association constant was calculated to be log βo=11.08±0.03 in the DCE phase. The association constant of other alkali metals (Li+, K+, Rb+) were also obtained.
Single‐Wall Carbon Nanotube Paste Electrodes: a Comparison with Carbon Paste, Platinum and Glassy Carbon Electrodes via Cyclic Voltammetric Data
Authors: Antiochia Riccarda , Lavagnini Irma , Magno Franco , Valentini Federica , Palleschi Giuseppe
Published: May 2004

A new carbon electrode material, obtained by mixing single wall carbon nanotubes (SWNTs) with a mineral oil binder is studied. Carbon nanotube pastes show the special properties of carbon nanotubes combined with the various advantages of composite electrodes such as a very low capacitance (background current) and the possibility of an easy preparation, modification and renewal. A better knowledge of the characteristics of electrode reactions at carbon nanotube paste (CNTP) electrodes was obtained studying the electron transfer rates of various redox couples under different pretreatment conditions. A critical comparison with carbon paste (CP), platinum (Pt) and glassy carbon (GC) electrodes was also carried out. Capacitance and resistance values were also calculated for all electrodes investigated. Both untreated and treated CNTP electrodes showed a low resistance while the capacitance was markedly reduced with CNTP electrodes previously treated with concentrated nitric acid. An electrochemical pretreatment on CNTP electrodes was developed which showed an excellent result towards two‐electron quinonic structure species. After this treatment the heterogeneous standard rate constants for p‐methylaminophenol sulfate (MAP) and dopamine resulted to be significantly higher (2.1×10−2 cm/s and 2.0×10−2 cm/s, respectively) than those obtained with the other electrodes studied. Reproducibility, stability and storage characteristics of CNTP electrodes were also reported.
Effects of adrenaline administration on the interrenal gland of the newt, Triturus carnifex: Evidence of intraadrenal paracrine interactions
Authors: Capaldo A. , Gay F. , Valiante S. , Laforgia V. , Varano L.
Published: May 2004

The existence of paracrine control of steroidogenic activity by adrenochromaffin cells in Triturus carnifex was investigated by in vivo adrenaline (A) administration. The effects were evaluated by examination of the ultrastructural morphological and morphometrical features of the tissues as well as the serum levels of aldosterone, noradrenaline (NA), and adrenaline. In March and July, adrenaline administration reduced aldosterone release (from 187.23 ± 2.93 pg/ml to 32.28 ± 1.85 pg/ml in March; from 314.60 ± 1.34 pg/ml to 87.51 ± 2.57 pg/ml in July) from steroidogenic cells. The cells showed clear signs of lowered activity: they appeared full of lipid, forming large droplets. Moreover, adrenaline administration decreased the mean total number of secretory granules in the chromaffin cells in July (from 7.74 ± 0.74 granules/μm2 to 5.14 ± 1.55 granules/μm2). In this period T. carnifex chromaffin cells contain almost exclusively NA granules (NA: 7.42 ± 0.86 granules/μm2; A: 0.32 ± 0.13 granules/μm2). Adrenaline administration reduced noradrenaline content (4.36 ± 1.40 granules/μm2) in the chromaffin cells, enhancing noradrenaline secretion (from 640.19 ± 1.65 pg/ml to 1030.16 ± 3.03 pg/ml). In March, adrenaline administration did not affect the mean total number of secretory vesicles (from 7.24 ± 0.18 granules/μm2 to 7.25 ± 1.97 granules/μm2). In this period the chromaffin cells contain both catecholamines, noradrenaline (3.88 ± 0.13 granules/μm2), and adrenaline (3.36 ± 0.05 granules/μm2), in almost equal quantities; adrenaline administration reduced adrenaline content (1.74 ± 0.84 granules/μm2), increasing adrenaline release (from 681.27 ± 1.83 pg/ml to 951.77 ± 4.11 pg/ml). The results of this study indicate that adrenaline influences the steroidogenic cells, inhibiting aldosterone release. Adrenaline effects on the chromaffin cells (increase of noradrenaline or adrenaline secretion) vary according to the period of chromaffin cell functional cycle. The existence of intraadrenal paracrine interactions in T. carnifex is discussed. J. Morphol. 261:18–25, 2004. © 2004 Wiley‐Liss, Inc.
Variation in seasonal ultrastructure of sexual granules in the renal sexual segment of the Northern Water Snake, Nerodia sipedon sipedon
Authors: Krohmer Randolph W.
Published: May 2004

The renal sexual segment of the kidney (RSS) can be found in many male squamate reptiles, encompassing the distal region of the nephron and, in some cases, collecting ducts. This sexually dimorphic structure exhibits varying degrees of hypertrophy and regression throughout the year. Although researchers have been aware of and have investigated this unique structure for over a century, its ultimate function remains under discussion. In many studies hypertrophy and regression of the RSS have been correlated with testicular activity and androgen secretion. As in most of the snakes studied to date, the male Northern Water Snake (Nerodia s. sipedon) does not exhibit a dramatic cycle of hypertrophy and regression, as reported in lizards. Following the initial hypertrophy at maturity, the male Northern Water Snake maintains a level of RSS hypertrophy throughout the year. Variations in the appearance and makeup of the sexual granules provide an identifiable and quantifiable seasonal pattern that can be correlated with the concentration of plasma androgens. In the Northern Water Snake, plasma androgens are elevated upon emergence and the RSS epithelial cells are filled with solid granules. As androgen levels decline during spring, sexual granule content appears to be breaking down (utilized?), becoming diffuse in appearance. By mid‐ to late summer androgen synthesis is at a maximum, increasing circulating androgens and stimulating the development and return of the solid granules. This study utilized electron microscopy and steroid radioimmunoassay to examine seasonal cycles of sex granules, in terms of development, maintenance, and regression, correlated with plasma androgen concentration. In addition, this investigation provides evidence of a possible secondary source of androgen secretion. J. Morphol. 261:70–80, 2004. © 2004 Wiley‐Liss, Inc.
Morphometric analysis of the larval branchial chamber in the dragonfly Aeshna cyanea Müller (Insecta, Odonata, Anisoptera)
Authors: Kohnert Stefan , Perry Steven F. , Schmitz Anke
Published: May 2004

The aquatic larvae of anisopteran dragonflies possess tracheal gills located in the rectum. Using stereological methods, we estimated the morphometric diffusing capacity for oxygen (DMO2) across the gill epithelium, i.e., from rectal water to the gill tracheoles, in the larvae of Aeshna cyanea. A 271‐mg larva has a total branchial surface area of ∼12 cm2. Tracheoles make up 6% of the epithelial volume of the gills; the harmonic mean thickness of the water–tracheolar diffusion barrier is 0.27 μm and consists mainly of cuticle. The calculated DMO2 is 23.0 μl min‐1 g‐1 kPa‐1, which, using published values for oxygen consumption in a similar species, would result in a mean driving pressure of 0.2 kPa at rest and 1.3 kPa during activity. Since these driving pressures are similar to those reported for other arthropods, we conclude that the DMO2 of the gill is not rate‐limiting for aerobic metabolism in Aeshna cyanea larvae. J Morphol. 261:81–91, 2004. © 2004 Wiley‐Liss, Inc.
Three‐dimensional model of the feline hindlimb
Authors: Burkholder Thomas J. , Nichols T. Richard
Published: May 2004

This article describes a three‐dimensional musculoskeletal model of the feline hindlimb based on digitized musculoskeletal anatomy. The model consists of seven degrees of freedom: three at the hip and two each at the knee and ankle. Lines of action and via points for 32 major muscles of the limb are described. Interspecimen variability of muscle paths was surprisingly low; most via points displayed a scatter of only a few millimeters. Joint axes identified by mechanical techniques as noncoincident and nonorthogonal were further honed to yield moment arms consistent with previous reports. Interspecimen variability in joint axes was greater than that of muscle paths and highlights the importance of joint axes in kinematic models. The contribution of specific muscles to the direction of endpoint force generation is discussed. J. Morphol. 261:118–129, 2004. © 2004 Wiley‐Liss, Inc.
Visualization of planar stress distributions in cucumber cultivars using a multiple‐point sheet sensor
Authors: Dan Haruka , Okuhara Kazutake , Kohyama Kaoru
Published: May 2004

Planar stress distribution of cucumber fruits was visualized for four cultivars. The planer stress distribution of a cross‐sectional sample was measured using a multiple‐point sheet sensor during uniaxial compression by an Instron universal testing machine. The concentric distribution pattern of stress gradients was the common characteristic for all cultivars. The correspondence between the tissue and its mechanical properties was estimated by comparing the stress distribution and a sample photograph. The stress property differed among different tissues within the cross‐section. The center of the cross‐sectional slice, where the seed cavity occupies formed the lower stress region, the surrounded area, where the flesh locates showed the middle‐range stress, and the exterior skin exhibited the highest stress. The wider distribution of the lower stress was statistically significant for two cultivars. This visualization method provided qualitative information about the geometrical and mechanical distribution of the cucumber and allowed the breed specificity of the cucumber cultivar to be characterized. Copyright © 2004 Society of Chemical Industry
Pesticide residues in field‐sprayed and processed fruits and vegetables
Authors: Chavarri María Jesús , Herrera Antonio , Ariño Agustin
Published: May 2004

This study was initiated to determine what residues of six insecticides (organochlorine, organophosphorus and pyrethroids) and four dithiocarbamate fungicides remained on raw agricultural commodities after harvest and to study the effect of the subsequent commercial processing on the residues. Sprayed crops of tomatoes, red peppers, asparagus, spinach, artichokes and peaches harvested after controlled field trials contained residues well below the maximum residue levels, except for lindane in tomatoes and acephate in artichoke. Commercial processing procedures led to large reductions in residue levels in the finished products. Washing removed all residual lindane, chlorpyrifos and cypermethrin from tomatoes. Chlorpyrifos residues were reduced by 67% during wood‐fire roasting of peppers, and subsequent peeling removed all the remains. Peeling and blanching of asparagus reduced chlorpyrifos concentrations to undetectable levels. Processing of artichokes eliminated acephate and chlorpyrifos after blanching. Acephate in peaches survived successive processing steps until the final heat process that destroyed remaining residues. The net results can contribute to assure the consumer of a safe wholesome food supply. Copyright © 2004 Society of Chemical Industry
Charge‐transfer exciton trapping at vacancies in molecular crystals: photoconductivity quenching, optical damage and detonation
Authors: Munn R.W. , Tsiaousis D.
Published: May 2004

Calculations are presented that show that vacancies can trap charge‐transfer (CT) states in anthracene, acetanilide and hexahydro‐1,3,5‐trinintro‐1,3,5‐triazine (RDX). Such trapping provides a mechanism for photoconductivity quenching by geminate recombination, and for optical damage and detonation by concentrating optical or mechanical energy stored in CT states.
Optical grating recording in highly organized thin films of Disperse Red 1
Authors: Miniewicz A. , Solyga M. , Taunaumang H. , Tija M.O.
Published: May 2004

Optical grating recording with submicrometer spatial resolution, which can handle grey‐level patterns, has been investigated in photochromic material made of Disperse Red 1 (DR1) molecules vacuum‐deposited on a glass substrate. Holographic gratings of periods Λ within the range of 0.6 μm ‐ 12 μm were recorded by 514.5 nm light from cw Ar+ laser using a degenerate two‐wave mixing technique. Despite the very small DR1 layer thickness (∼ 0.1 μm), the diffraction efficiency measured in a Raman‐Nath scattering regime reached 2 %. The obtained amplitude gratings were analysed with an optical microscope and Fourier transforms. Grating profiles were analysed in relation to exposure conditions and in correlation with molecular organisation. Polarising microscopy studies revealed the presence of light‐induced optical anisotropy. Following that, we have checked the possibility of polarisation‐sensitive recording in this medium.
Stable coaxial waveguide‐port algorithm for the time‐domain finite‐element method
Authors: Rylander Thomas , Jin Jian‐Ming
Published: May 2004

A new coaxial waveguide‐port algorithm is developed and tested for the time‐domain finite‐element method. The electric field is modeled by edge elements and, for part of a coaxial cable or a similar transmission line, the full Maxwell's equations are reduced to the one‐dimensional transmission‐line equation through the use of macro elements, which represent the dominant waveguide mode. The port algorithm converges quadratically with the cell size for geometries with smooth boundaries, which is demonstrated by tests on a coaxial cable with a short‐circuit termination. The port algorithm is proven to be stable up to the Courant limit of the explicit scheme used for the transmission‐line equation, without any added artificial dissipation. The proposed port algorithm preserves, by construction, the reciprocity of Maxwell's equations. For a 2 × 2‐array of patch antennas, computation of the coupling of the antenna elements demonstrates that the scattering matrix is symmetric or, equivalently, that the proposed algorithm preserves reciprocity. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 115–119, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20225
Prevalence of lymphoreticular prion protein accumulation in UK tissue samples
Authors: Hilton David A , Ghani Azra C , Conyers Lisa , Edwards Philip , McCardle Linda , Ritchie Diane , Penney Mark , Hegazy Doha , Ironside James W
Published: May 2004

This study aims to provide an estimate of the number of individuals in the UK who may be incubating variant Creutzfeldt‐Jakob disease and at risk of causing iatrogenic spread of the disease. Lymphoreticular accumulation of prion protein is a consistent feature of variant Creutzfeldt‐Jakob at autopsy and has also been demonstrated in the pre‐clinical phase. Immunohistochemical accumulation of prion protein in the lymphoreticular system remains the only technique that has been shown to predict neurological disease reliably in animal prion disorders. In this study, immunohistochemistry was used to demonstrate the presence of prion protein, with monoclonal antibodies KG9 and 3F4, in surgically removed tonsillectomy and appendicectomy specimens. The samples were collected from histopathology departments across the UK and anonymised prior to testing. Samples were tested from 16 703 patients (14 964 appendectomies, 1739 tonsillectomies), approximately 60% of whom were from the age group 20–29 years at operation. Twenty‐five per cent of the samples were excluded from the final analyses because they contained inadequate amounts of lymphoid tissue. Three appendicectomy samples showed lymphoreticular accumulation of prion protein, giving an estimated prevalence of 3/12 674 or 237 per million (95% CI 49–692 per million). The pattern of lymphoreticular accumulation in two of these samples was dissimilar from that seen in known cases of variant Creutzfeldt‐Jakob disease. Although it is uncertain whether immunohistochemical accumulation of prion protein in the lymphoreticular system is specific for variant Creutzfeldt‐Jakob disease, it has not been described in any other disease, including other forms of human prion disease or a range of inflammatory and infective conditions. These findings reinforce the importance of measures taken by the UK Department of Health to reduce the risk of spread of variant Creutzfeldt‐Jakob via blood products and surgical instruments, and of the urgency to proceed with large‐scale screening of fresh tonsil specimens for the presence of prion protein. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Prenatal diagnosis of a fetus harboring an intermediate load of the A3243G mtDNA mutation in a maternal carrier diagnosed with MELAS syndrome
Authors: Chou Yin‐Jou , Ou Chia‐Yu , Hsu Te‐Yao , Liou Chia‐Wei , Lee Cheng‐Feng , Tso Dan‐Ju , Wei Yau‐Huei
Published: May 2004

We prenatally diagnosed MELAS syndrome in a fetus whose mother and older brother had the MELAS‐specific A3243G mutation. The mutant mtDNA level of the amniotic fluid cells was not significantly different from that of the postnatal peripheral blood and hair follicle samples. The obstetrical course was uncomplicated except for transient exacerbation of the mother's diabetes, which required insulin control. At term, the infant was macrosomic, and the delivery was complicated by shoulder dystocia. MELAS syndrome in itself does not influence either the prenatal course of the mother or the fetal outcome. In contrast to the fulminating clinical course of this mother's first child, MELAS symptoms did not develop in her second child until age four, despite similar high tissue levels of mutant mtDNA. The phenotypic diversity in two offspring with similar higher levels of mutant mtDNA suggests that prenatal genetic diagnosis of cultured amniotic cells may yield results that are poor prognosticators of fetal outcome. Copyright © 2004 John Wiley & Sons, Ltd.
Contact stiffness of initially stressed neo‐Hookean solids
Authors: Yang Fuqian
Published: May 2004

This work, using the solution given by Dhaliwal and Singh, presents analytical expressions of the incremental stress and displacement fields for the axisymmetrical indentation of initially stressed, incompressible neo‐Hookean solids. A simple relation for the contact stiffness, contact area, elastic constants, and finite stretch can be obtained for the indentation by any rigid axisymmetric indenter, which can be described as a smooth function. The contact stiffness increases with the initial finite stretching; the finite stretching makes materials harder to deform. The results provide a basis for evaluating the effects of residual stresses on the nanoindentation of materials from the viewpoint of finite deformation. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2513–2521, 2004
On the number of full levels in tries
Authors: Knessl Charles , Szpankowski Wojciech
Published: May 2004

We study the asymptotic distribution of the fill‐up level in a binary trie built over n independent strings generated by a biased memoryless source. The fill‐up level is the number of full levels in a tree. A level is full if it contains the maximum allowable number of nodes (e.g., in a binary tree level k can have up to 2k nodes). The fill‐up level finds many interesting applications, e.g., in the internet IP lookup problem and in the analysis of level compressed tries (LC tries). In this paper, we present a complete asymptotic characterization of the fill‐up distribution. In particular, we prove that this distribution concentrates on one or two points around the most probably value k = ⌊log1/qn − log log log n + 1 + log log(p/q)⌋, where p > q = 1 − p is the probability of generating the more likely symbol (while q = 1 − p is the probability of the less likely symbol). We derive our results by analytic methods such as generating functions, Mellin transform, the saddle point method, and analytic depoissonization. We also present some numerical verification of our results. © 2004 Wiley Periodicals, Inc. Random Struct. Alg., 2004