bluuebunny/crossref_metadata_2025 huggingface dataset:
Two‐photon analysis of calcium signals in T lymphocytes of intact lamina propria from human intestine
Authors: Tutsch Eberhard , Griesemer Désirée , Schwarz Alexander , Stallmach Andreas , Hoth Markus
Published: October 2004

Lamina propria (LP) T cells of the human intestinal mucosa usually do not develop systemic immune responses despite permanent exposure to foreign antigens. The mechanisms maintaining this hyporeactivity in the normal gut are poorly understood. It is, at present, not clear what role the microenvironment of the mucosa plays for low T cell reactivity and in the pathogenesis of mucosal inflammation. Despite the importance of cytosolic Ca2+ signals for T lymphocyte activation, intracellular Ca2+ concentration measurements have so far only been performed in dissociated T cells, following disruption of the microenvironment. We used two‐photon technology to measure Ca2+ signals in identified T lymphocytes within the intact mucosa to minimize impact on tissue integrity while preserving the cellular microenvironment. We show that Ca2+ signals in LP T cells correlate with the hyporeactivity of T cells in the intestinal immune system and furthermore link Ca2+ signals with inflammatory bowel disease. Our data implicate that Ca2+ signals in LP T cells do not depend on the microenvironment of the intact mucosa, since they are very similar to Ca2+ signals in dissociated LP T cells.
Monoclonal antibody to a DNA‐binding domain of p53 mimics charge structure of DNA: anti‐idiotypes to the anti‐p53 antibody are anti‐DNA
Authors: Herkel Johannes , Kam Na'aman , Erez Neta , Mimran Avishai , Heifetz Alexander , Eisenstein Miriam , Rotter Varda , Cohen Irun R.
Published: October 2004

Antibodies to DNA are important markers of various autoimmune diseases and can be pathogenic; however, their generation is not understood. We previously reported that anti‐DNA antibodies could be induced in mice by idiotypic immunization to PAb‐421, an antibody to a DNA‐binding domain of p53. We now report that two monoclonal antibodies of moderate affinity (KD≈︁10–7), raised from PAb‐421‐immunized mice, specifically recognized both PAb‐421 and DNA. These antibodies feature multiple arginine residues in the antigen‐binding site, a unique characteristic of disease‐associated anti‐DNA antibodies; nevertheless, these anti‐DNA antibodies show specific complementarity to PAb‐421 by competing with p53 for PAb‐421 binding and recognize defined oligonucleotides with a specificity similar to that of p53. To study the structural basis for the cross‐recognition of PAb‐421 and DNA by the anti‐DNA antibodies, we constructed computer models (fine‐tuned by protein‐protein docking) of PAb‐421 and one of the monoclonal anti‐DNA antibodies. The modeled structures manifested structural complementarity. Most notably, the modeled structure of PAb‐421 resembled the structure of DNA by the positions of negatively charged groups and aromatic side chains. Thus, a protein molecule may mimic the structure of DNA and the elusive generation of anti‐DNA antibodies could be explained by idiotypic immunity to a DNA‐binding protein, like p53.
Identification of a naturally processed cyclin D1 T‐helper epitope by a novel combination of HLA class II targeting and differential mass spectrometry
Authors: Dengjel Jörn , Decker Patrice , Schoor Oliver , Altenberend Florian , Weinschenk Toni , Rammensee Hans‐Georg , Stevanovic Stefan
Published: October 2004

T‐helper (Th) cells play an important role in orchestrating the effector function of CTL in anti‐tumor immunity. However, only a limited number of Th cell epitopes has been characterized. Here we describe a novel approach for identifying naturally processed and presented peptides derived from chosen antigens. This method combines a transfection step of antigen‐presenting cells with a vector encoding a fusion protein between the Ii chain and the antigen of interest, elution of the HLA‐bound peptides and identification of the antigen‐derived peptides by mass spectrometric comparison to the non‐transfected cells. In vitro‐stimulated Th cells against the identified peptide of interest specifically recognize transfectants overexpressing the cognate antigen. Using this approach, we were able to identify the HLA‐DR4‐restricted Th cell epitope NPPSMVAAGSVVAAV derived from cyclin D1, which is frequently overexpressed in tumors. This method will help in identifying peptide candidates for vaccination studies for tumor immunotherapy.
Utilisation of 1,3‐Dicarbonyl Derivatives in Multicomponent Reactions
Authors: Simon Céline , Constantieux Thierry , Rodriguez Jean
Published: October 2004

Although isocyanide‐based multicomponent reactions (MCRs), introduced in 1921 by Passerini, largely predominate nowadays in the construction of widely diverse heterocycles, one of the first substrate classes involved in a MCR was that of 1,3‐dicarbonyl derivatives, with Hantzsch’s dihydropyridine synthesis appearing as early as 1882. The aim of this microreview is to present an overview of the great synthetic potential of MCRs involving the specific reactivity of easily accessible 1,3‐dicarbonyl derivatives and to stress their more recent utilisation for the development of new and useful methodologies valuable for the selective construction of highly functionalised small organic molecules of high synthetic and biological value. After a short general introduction, we present chronologically the different methodologies developed on the bases of the reactivity of 1,3‐dicarbonyl systems towards many other substrates involved in a variety of synthetic pathways, including Knoevenagel condensations, Michael and Mannich reactions, cyclodehydrations, electrocyclisations, cycloadditions and metal‐promoted transformations. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Determination of Platinum with Thiosemicarbazide by Catalytic Adsorptive Stripping Voltammetry (AdSV)
Authors: Huszal Sylwester , Kowalska Joanna , Krzeminska Magdalena , Golimowski Jerzy
Published: October 2004

This work describes a very sensitive and selective voltammetric procedure for the determination of platinum. Instead of commonly used hydrazine, thiosemicarbazide as a component of supporting electrolyte was applied. The method is based on adsorption of platinum‐thiosemicarbazone complex, formed in situ in voltammetric cell from thiosemicarbazide and formaldehyde, coupled with a hydrogen catalytic reaction at a hanging mercury drop electrode. The linear relation between platinum concentration and height of analytical signal was observed up to 1.5×10−9 mol L−1 with the detection limit calculated as 1.5×10−13 mol L−1 (3 s of the blank) after 50 s of accumulation time. The effect of various interferences from other ions was studied. Described method was applied for platinum determination in hydroponically cultivated plants after microwave decomposition.
Inlaid Multi‐Walled Carbon Nanotube Nanoelectrode Arrays for Electroanalysis
Authors: Li Jun , Koehne Jessica E. , Cassell Alan M. , Chen Hua , Ng Hou Tee , Ye Qi , Fan Wendy , Han Jie , Meyyappan M.
Published: October 2004

The rapid development in nanomaterials and nanotechnologies has provided many new opportunities for electroanalysis. We review our recent results on the fabrication and electroanalytical applications of nanoelectrode arrays based on vertically aligned multi‐walled carbon nanotubes (MWCNTs). A bottom‐up approach is demonstrated, which is compatible with Si microfabrication processes. MWCNTs are encapsulated in SiO2 matrix leaving only the very end exposed to form inlaid nanoelectrode arrays. The electrical and electrochemical properties have been characterized, showing well‐defined quasireversible nanoelectrode behavior. Ultrasensitive detection of small redox molecules in bulk solutions as well as immobilized at the MWCNT ends is demonstrated. A label‐free affinity‐based DNA sensor has shown extremely high sensitivity approaching that of fluorescence techniques. This platform can be integrated with microelectronics and microfluidics for fully automated microchips.
Achieving Direct Electrical Connection to Glucose Oxidase Using Aligned Single Walled Carbon Nanotube Arrays
Authors: Liu Jingquan , Chou Alison , Rahmat Wibowo , Paddon‐Row Michael N. , Gooding J. Justin
Published: October 2004

Direct electron transfer between an electrode and the redox active centre of glucose oxidase, flavin adenine dinucleotide (FAD), is probed using carbon nanotube modified gold electrodes. Gold electrodes are first modified with a self‐assembled monolayer of cysteamine and then shortened single walled carbon nanotubes (SWNT) are aligned normal to the electrode surface by self‐assembly. The electrochemistry of these aligned nanotube electrode arrays is initially investigated using potassium ferricyanide which showed SWNT act as nanoelectrodes with the ends of the tubes more electrochemically active than the walls. Subsequently the nanotubes are plugged into the enzymes in one of two ways. In the first method, native glucose oxidase is covalently attached to the ends of the aligned tubes which allowed close approach to FAD and direct electron transfer to be observed with a rate constant of 0.3 s−1. In the second strategy, FAD was attached to the ends of the tubes and the enzyme reconstituted around the surface immobilized FAD. This latter approach allowed more efficient electron transfer to the FAD with a rate constant of 9 s−1.
A Disposable Biosensor for Organophosphorus Nerve Agents Based on Carbon Nanotubes Modified Thick Film Strip Electrode
Authors: Joshi Kanchan A. , Tang Jason , Haddon Robert , Wang Joseph , Chen Wilfred , Mulchandani Ashok
Published: October 2004

A disposable biosensor based on acetylcholinesterase‐functionalized acid purified multi‐wall carbon nanotubes (CNTs) modified thick film strip electrode for organophosphorus (OP) insecticides was developed. The degree of inhibition of the enzyme acteylcholinesterase (AChE) by OP compounds was determined by measuring the electrooxidation current of the thiocholine generated by the AChE catalyzed hydrolysis of acteylthiocholine (ATCh). The large surface area and electro‐catalytic activity of carbon nanotubes lowered the overpotential for thiocholine oxidation to 200 mV (vs. Ag/AgCl) without the use of mediating redox species and enzyme immobilization by physical adsorption. The biosensor detected as low as 0.5 nM (0.145 ppb) of the model organophosphate nerve agent paraoxon with good precision, electrode to electrode reproducibility and stability. Analysis of real water sample using the sensor demonstrated the feasibility of the application of the sensor for on site monitoring of OP compounds.
Scanning Electrochemical Microscopy as an In Vitro Technique for Measuring Convective Flow Rates Across Dentine and the Efficacy of Surface Blocking Treatments
Authors: Macpherson Julie V. , Unwin Patrick R.
Published: October 2004

Scanning electrochemical microscopy (SECM) is shown to be a powerful technique for both the measurement of local solution velocities through human dentine slices, in vitro, and for assessing quantitatively the effect of surface treatments on the flow process. SECM employs a small ultramicroelectrode (micron dimensions) as an imaging probe to provide information on the topography and transport characteristics of dentine, with high spatial resolution. In these studies the dentine sample is a membrane in a two compartment cell, which contains solutions of identical composition, including a redox active mediator (Fe(CN)$\rm{ {_{6}^{4-}})}$. In the absence of an applied pressure, the transport‐limited current response at the probe electrode is due to diffusion of Fe(CN)$\rm{ {_{6}^{4-}}}$ to the UME, which depends on the probe to sample separation. Under an applied hydrostatic pressure, hydrodynamic flow across the sample enhances mass transport to the UME. With this methodology it was possible to accurately measure effective fluid velocities, by recording tip currents with and without pressure, and assess the efficacy of potential flow retarding agents for the treatment of dentinal hypersensitivity. For native dentine, the solution velocity was found to vary dramatically with location on the sample. The application of a glycerol monooleate ‐ base paste treatment to the surface of dentine was found to lower local flow velocities significantly. This electroanalytical methodology is simple to implement and is generally applicable to assessing the efficacy and mode of action of a wide variety of potential fluid flow retarding agents.
An evaluation of Endangered Species Act exemptions in the department of defense and the U.S. Air Force
Authors: Sitzabee William E. , Bleckmann Charles A. , England Ellen C.
Published: October 2004

The 2004 National Defense Authorization Act (NDAA) granted relief to the Department of Defense (DOD) on compliance with certain provisions of the Endangered Species Act (ESA). Specifically, the Secretary of the Interior was mandated to exempt DOD from critical habitat designation on military installations provided that the installation had an Integrated Natural Resources Management Plan (INRMP), as required by the Sikes Act, and the resources to effectively implement the plan. DOD viewed this legislative relief as an important step in addressing one element of general encroachment concerns on military lands. This article reviews the background of the critical habitat issue on military lands and the steps that led to the provisions included in the 2004 NDAA. To determine the status and degree of implementation of the ESA provisions of the 2004 NDAA in the U.S. Air Force (USAF), the principal author conducted a survey of USAF range natural resources managers. The results of that survey indicate that the USAF is meeting the requirements of the 2004 NDAA by having valid INRMPs for its installations and by providing adequate funding for their implementation. However, the survey results suggested several areas where improvement was needed, particularly in educating natural resources managers about documenting the impacts of critical species on training ranges, partnering with outside groups to leverage manpower and financial resources, and improving public education and awareness of USAF training range environmental programs. © 2004 Wiley Periodicals, Inc.
A framework and methodology for establishing degraded military skills due to encroachment of training ranges
Authors: Reinke Paul
Published: October 2004

Encroachment at many military ranges and training facilities is negatively impacting the realism and effectiveness of military training. To clearly link the presence of encroachment pressures to degraded military training requires an analytical approach that embraces encroachment pressures, range capability to support training, the skill proficiencies acquired by units trained at the facility, and the quality of the mission‐essential task training experience. Most importantly, this approach must discriminate between the encroachment pressures that can be managed, such as critical habitat conservation and endangered species protection, and the pressures that cannot, such as population growth or range capacity limits.

A reasonable indicator of degraded training—as evidenced by skill‐proficiency levels—can be shown for military units using specific ranges to conduct mission task training. Degraded training can be quantified as either a score or an index depending upon further uses for this information. The root causes of degraded training are determined by analysis of the data captured during examination of the collective mission training tasks. © 2004 Wiley Periodicals, Inc.
Treatment of energetic hazardous waste by open detonation at the Naval Air Weapons Station, China Lake, California
Authors: Zellmer Lauren A. , Boggs Thomas L. , Erickson Eric D. , Chafin Andrew P.
Published: October 2004

The Naval Air Weapons Station, China Lake, California, is the Navy's largest research, development, test, and evaluation (RDT&E) facility, encompassing more than 1.1 million acres. The State of California has a long tradition of strong enforcement of strict environmental standards. The treatment of energetic wastes by open burn/open detonation (OB/OD) has been a matter of considerable controversy in some of parts of the state, as well as areas around the country. With a science‐based, data‐driven approach, a team of China Lake environmental specialists and technical experts in the research and energetics area establishes the validity of OD as a preferred treatment method.

The anticipated outcome of China Lake's efforts is the approval by state regulatory agencies of a revised human health risk assessment (HRA). The purpose of the HRA is to address potential health effects (both cancer and non‐cancer) from exposure to emissions from OB/OD activities on human receptors. In order to ensure that the revised HRA is based on valid scientifically backed data that can withstand public and regulatory scrutiny, China Lake has focused efforts on three areas: (1) development of a validated emission factor database from actual test data; (2) fate of metal casings associated with the OD of munitions; and (3) OD simulation tests for energetic‐contaminated wastes. This article discusses all three efforts. © 2004 Wiley Periodicals, Inc.
Innovative stormwater management at Marine Corps Air Station, New River
Authors: Kropinack Kirk R.
Published: October 2004

Because of the nature of Marine Corps Air Station, New River, there are several stormwater management challenges it faces. The station's location in coastal North Carolina means that it is located within a uniquely sensitive environment. Additionally, being an airport, there is a large number of impervious areas and Bird/Animal Strike Hazard (BASH) concerns. This article discusses three stormwater management initiatives undertaken by the station: (1) diverting stormwater inflow from the sanitary sewer system, (2) evaluating stormwater management techniques, such as low‐impact development, that are not stormwater ponds (which cause enhanced BASH concerns), and (3) assuring all station personnel are aware of their responsibilities at work to avoid releases with the use of simple, easy‐to‐understand environmental signage. © 2004 Wiley Periodicals, Inc.
Miscellaneous organic NESHAP compliance for a new countermeasure flare production facility at the Milan Army Ammunition Plant
Authors: Knisley Dennis R. , Evans Louis A. , Goodwin Edward , McKnight Charles
Published: October 2004

FR Countermeasures, Inc. (FRC), a division of Flight Refuelling Ltd. of the United Kingdom, has sited a countermeasure flare production facility at the Milan Army Ammunition Plant (MLAAP) in Milan, Tennessee. Franklin Engineering Group, Inc. (Franklin Engineering) worked in cooperation with FRC to develop an air permitting strategy that would allow expedited regulatory review and approval to meet an aggressive construction schedule. This strategy addressed eventual compliance with the 40 CFR, Subpart FFFF (Miscellaneous Organic NESHAP (MON) standard) by permitting the facility as a conditional major source to allow for construction, start‐up, and initial operation with eventual operation as a major source (i.e., Title V) at full processing rates.

The facility was modeled after Flight Refuelling Ltd.'s North Stockbridge, U.K., manufacturing facility, with several important distinctions. First, the regulatory standards for air emissions from this type of facility in the United States, in combination with a higher production capacity, necessitated a higher level of control for hazardous air pollutants (HAPs). Additionally, FRC had to address increased volume of effluent water from the solvent recovery process and carbon regeneration process. Finally, this effluent water had to meet the Sewer Use Agreement, which required additional acetone removal prior to discharge to the sewer. The selection of an integrated air pollution control system to achieve these environmental objectives required special consideration of safety issues inherent to energetics manufacturing.

After consideration of several air pollution control technologies, FRC and Franklin Engineering selected an activated carbon adsorption system for treatment of combined gases from two main batch sources: mixing and drying processes. This system will achieve greater than 95 percent recovery of HAPs from these processes, as required for regulatory purposes. Carbon beds are regenerated via steam stripping to yield two streams: recovered hydrocarbons and a recondensed aqueous stream. Recovered solvents are reused or sold. The aqueous stream is combined with water from the batch wash process and steam stripped for solvent recovery. Crucial to assuring safe operation of the air pollution control system was the utilization of a flame isolation valve with gas cartridge actuators to eliminate potential flame/deflagration passage between each process unit. © 2004 Wiley Periodicals, Inc.
RCRA and UIC obligations attendant to closing a facility
Authors: Shearer C. Russell H. , Heath John H.
Published: October 2004

The current competitive global business environment, coupled with the considerations brought about by the existing regulatory regime, might yield the conclusion that a particular facility is too expensive to operate, and that placing it in cold standby or shuttering it altogether is the more cost‐effective course. Even in this analysis, cost is an important consideration, particularly the cost of complying with the myriad environmental obligations that will govern a facility's placement in cold standby or closure, because numerous environmental requirements attach to closing a plant. Two of the most important sources of those requirements for facilities that manage hazardous waste and injection‐well facilities are the Resource Conservation and Recovery Act (RCRA) and the Safe Drinking Water Act (SDWA). Plants must hold a RCRA permit to operate hazardous waste storage units, hazardous waste landfills, and hazardous waste container storage areas, which must also be closed in accord with that statute, especially the unit‐specific requirements for landfills and surface impoundments. The SDWA governs plants with underground injection wells, which must have an Underground Injection Control permit to operate. This permit governs closure and postclosure activities for the underground injection wells. Finally, other agreements, such as Consent Decrees, may attach closure, postclosure, and interim obligations. © 2004 Wiley Periodicals, Inc.
Two‐dimensional anisotropic Cartesian mesh adaptation for the compressible Euler equations
Authors: Keats W. A. , Lien F.‐S.
Published: October 2004

Simulating transient compressible flows involving shock waves presents challenges to the CFD practitioner in terms of the mesh quality required to resolve discontinuities and prevent smearing. This paper discusses a novel two‐dimensional Cartesian anisotropic mesh adaptation technique implemented for transient compressible flow. This technique, originally developed for laminar incompressible flow, is efficient because it refines and coarsens cells using criteria that consider the solution in each of the cardinal directions separately. In this paper, the method will be applied to compressible flow. The procedure shows promise in its ability to deliver good quality solutions while achieving computational savings.

Transient shock wave diffraction over a backward step and shock reflection over a forward step are considered as test cases because they demonstrate that the quality of the solution can be maintained as the mesh is refined and coarsened in time. The data structure is explained in relation to the computational mesh, and the object‐oriented design and implementation of the code is presented. Refinement and coarsening algorithms are outlined. Computational savings over uniform and isotropic mesh approaches are shown to be significant. Copyright © 2004 John Wiley & Sons, Ltd.
The impact of diabetes on employment: genetic IVs in a bivariate probit
Authors: Shelton Brown H. , Pagán José A. , Bastida Elena
Published: October 2004

Diabetes has been shown to have a detrimental impact on employment and labor market productivity, which results in lost work days and higher mortality/disability. This study utilizes data from the Border Epidemiologic Study on Aging to analyze the endogeneity of diabetes in an employment model. We use family history of diabetes as genetic instrumental variables. We show that assuming that diabetes is an exogenous variable results in an overestimate (underestimate) of the negative impact of diabetes on female (male) employment. Our results are particularly relevant in the case of populations where genetic predisposition has an important role in the etiology of diabetes. Copyright © 2004 John Wiley & Sons, Ltd.
Correcting for compensating mechanisms related to productivity costs in economic evaluations of health care programmes
Authors: Jacob‐Tacken Karin H. M. , Koopmanschap Marc A. , Meerding Willem Jan , Severens Johan L.
Published: October 2004

In the economic evaluation of health care programmes, productivity costs are often estimated using patients' wages for the period of absence. However, the use of such methods for short periods of absence is controversial. A previous study found that short‐term absence is often compensated for during normal working hours and therefore does not lead to productivity losses. As such, the application of any approach almost certainly overestimates productivity costs. In this study, we examined the productivity costs for five different patient populations and one employee population, using the classical method and by identifying when extra effort was needed. In general, the results showed that productivity costs based on identifying extra effort were 25–30% of the classical estimates. For absences of just one day, productivity costs were relevant in only 17–19% of cases. For absences of two weeks or longer, productivity costs were relevant in 35–39% of cases. Measurement of the compensating mechanisms seemed to be valid, since there is considerable agreement between the opinion of supervisors and their employees about whether compensation covers productivity costs. There was much less agreement between supervisors and their employees on specific compensating mechanisms, however. The measurement of compensating mechanisms also seemed to be valid, because – as expected – different compensating mechanisms were reported for different occupations. In our study populations, compensating mechanisms appeared to differ with occupational characteristics, like part‐time work, managerial work and shift work. Copyright © 2004 John Wiley & Sons, Ltd.
Technology and managed care: patient benefits of telemedicine in a rural health care network
Authors: Berman Matthew , Fenaughty Andrea
Published: October 2004

Rural health providers have looked to telemedicine as a technology to reduce costs. However, virtual access to physicians and specialists may alter patients' demand for face‐to‐face physician access. We develop a model of service demand under managed care, and apply the model to a telemedicine application in rural Alaska. Provider‐imposed delays and patient costs were highly significant predictors of patient contingent choices in a survey of ENT clinic patients. The results suggest that telemedicine increased estimated patient benefits by about $40 per visit, and reduced patients' loss from rationing of access to physicians by about 20%. Copyright © 2004 John Wiley & Sons, Ltd.
Subsurface microstructure of metal‐on‐metal hip joints and its relationship to wear particle generation
Authors: Büscher R. , Täger G. , Dudzinski W. , Gleising B. , Wimmer M.A. , Fischer A.
Published: October 2004

To control and minimize wear of metal‐on‐metal hip joints it is essential to understand the mechanisms of debris generation.In vivo, mainly nanosize globular and needle‐shaped particles are found. These can neither stem from the action of abrasion nor from tribochemical reactions. In this study the acting wear mechanisms have been first identified on the surface by means of scanning electron microscopy (SEM). Afterwards, the microstructures of the subsurface regions of explants have been investigated using a transmission electron microscope (TEM). Observation of the subsurface gave additional insight about the microstructural changes of cobalt‐base alloys subjected to wear. At some distance from the surface, a network of stacking faults and hexagonal ϵ‐martensite was found strengthening the bulk material. This microstructure changed into a nanocrystalline type moving closer towards the surface. A comparison ofin vivodebris size and grain size of the surface suggests that the globular wear particles result from torn off nanocrystals, while the needle shaped particles are generated by fractured ϵ‐martensite. Identified cracks, propagating through the nanocrystalline layer, further support these findings. Thus, it is suggested that the dominating mechanism of particle generation for metal‐on‐metal joints is surface fatigue within a nanocrystalline surface layer. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 72B: 206–214, 2005
Pulpal temperature rise during light‐activated bleaching
Authors: Eldeniz Ayçe Unverdi , Usumez Aslihan , Usumez Serdar , Ozturk Nilgun
Published: October 2004

The purpose of this study was to measure intrapulpal temperature rise induced by two kinds of bleaching gels when the tooth was exposed to a variety of light‐curing units and a diode laser in vitro. The root portions of 80 extracted intact human maxillary central incisors were sectioned with a carborundum disk approximately 2 mm below the cementoenamel junction perpendicular to the long axis of the teeth. Two bleaching agents containing heat‐enhancing colorant was applied to the labial surface. Light‐curing units used were a conventional halogen (40 s), a high‐intensity halogen (30 s), a light‐emitting diode unit (40 s), and a diode laser (15 s). The temperature rise was measured in the pulpal chamber with a J‐type thermocouple wire that was connected to a data logger. Ten specimens were used for each system and bleaching‐agent combination. Differences between the starting temperature and highest temperature reading were taken and the calculated temperature changes were averaged to determine the mean value in temperature rise. Temperature rise values were compared using two‐way analysis of variance (ANOVA) at a preset α of 0.05. Temperature rise varied significantly depending on curing unit and diode laser used. The diode laser induced significantly higher temperature increases than any other curing unit (11.7°C). The light‐emitting diode unit produced the lowest temperature changes (6.0°C); however, there were no statistically significant differences among the curing units and there were no statistically significant differences between bleaching agents. Light activation of bleaching materials with diode laser caused higher temperature changes as compared to other curing units and the temperature rise detected was viewed as critical for pulpal health. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 72B: 254–259, 2005
Risk factors for renal dysfunction in the postoperative course of liver transplant
Authors: Gallardo Miguel Lebrón , Herrera Gutierrez Manuel E. , Pérez Gemma Seller , Balsera Emilio Curiel , Fernández Ortega Juan F. , García Guillermo Quesada
Published: October 2004

Renal dysfunction (RD) is a frequent complication after orthotopic liver transplantation (OLT), and it has an unfavorable effect on the prognosis of OLT patients. The purpose of our study was to identify possible risk factors for RD and its impact on survival. The possible relations of pre-, peri-, and postoperative variables to early-onset renal dysfunction (ED) (within the 1st 3 months), late-onset renal dysfunction (LD) (between 3 and 6 months), and chronic renal dysfunction (CRD) (beyond 6 months) was analyzed. We studied 245 liver transplants in 241 patients. RD was found in 64.1% of these patients, and 69% of the patients with RD recovered. LD was found in 16.7% of the transplant patients. In the multivariate analysis, baseline serum creatinine, perioperative volume of transfused bank-red blood cells, Acute Physiology and Chronic Health Evaluation (APACHE) II score at intensive care unit (ICU) admission, and infection were associated with the development of RD. Overall mortality was 27.8% and for the RD group, it was 33.5%. LD, but not ED, was related to lower survival (together with graft dysfunction and APACHE II score at ICU admission). In conclusion, ED is frequent alter OLT and is related to preexisting RD, the volume of transfused bank--red blood cells during surgery, higher APACHE II score at ICU admission, and infection. In general, the prognosis for ED is good, in contrast with that of LD, which is associated with diminished survival. (Liver Transpl 2004;10:1379-1385.)
Simplified standardized technique for living donor liver transplantation using left liver graft plus caudate lobe
Authors: Hwang Shin , Lee Sung-Gyu , Ha Tae-Yong , Ahn Chul-Soo , Park Kwang-Min , Kim Ki-Hun , Lee Young-Joo , Moon Deok-Bog , Kim Keon-Kuk , Kim Yeon-Dae
Published: October 2004

Concomitant resection of the caudate lobe (CL) would increase the liver mass in the left liver graft. We tried to define a simplified standardized technique for adult living donor liver transplantation using the extended left lobe (ELL) plus CL (ELLC) through a prospective study of 27 consecutive ELLC graft cases in 2003. Donor CL was dissected toward the 10 o’clock direction and transected at the midpoint between the trunks of the right hepatic vein (RHV) and the middle hepatic vein (MHV). This orthodox transection was performed in 18 cases, but the transection plane was moved left in 9 cases. Compared with conventional left liver implantation, there was no additional reconstruction except for single revascularization of the largest short hepatic vein of the CL (V1) in 21 cases. On 1-week computed tomography (CT) images, the perfusion states of the CL portion were good in 15 cases, fair in 7 cases, and poor in 5 cases. Regeneration of the CL portion during the 1st week was +43%, +18%, and −10% in the good, fair, and poor perfusion groups, respectively. There were positive correlations among the perfusion state of the CL, the location of the CL transection plane, and the width of the CL portion that was attached to the left liver graft. CL implantation resulted in a mean gain of graft mass by 5.9% in the left liver at the time of operation and by 3.9% after 1 week. There were no donor complications, and 25 recipients (93%) survive to date. In conclusion, this simplified standardized technique was feasible for most of the living donor livers and required only 1 additional reconstruction of the V1. (Liver Transpl 2004;10:1398-1405.)
Survival of cirrhotic patients with early hepatocellular carcinoma treated by percutaneous ethanol injection or liver transplantation†
Authors: Andriulli Angelo , de Sio Ilario , Solmi Luigi , De Carlis Luciano , Troisi Roberto , Grasso Alessandro , Festa Virginia , Caturelli Eugenio , Giacomoni Alessandro , Del Vecchio Blanco Camillo , De Hemptinne Bernard , Burroughs Andrew , Perri Francesco
Published: October 2004

For “early” hepatocellular carcinoma (HCC), surgery, orthotopic liver transplantation (OLT) and percutaneous ethanol injection (PEI) improve the natural history of the disease. We performed a retrospective study to evaluate the outcome of patients with cirrhosis and early HCC treated by PEI (n = 417) or OLT (n = 172). Overall, 589 patients with cirrhosis were studied. The proportion of patients in Child-Turcotte-Pugh (CTP) classes A, B, and C was 52.5%, 33.6%, and 13.9%, respectively. Most patients (78.9%) had solitary HCC. Overall 5-year and 10-year cumulative survival rates were 36.1% and 15.5% after PEI, and 66.3% and 49.1% after OLT, respectively (P < .0001). Overall 5-year and 10-year cumulative tumor-free survival rates were 25.3% and 18.0% after PEI, and 84.6% and 82.2% after OLT, respectively (P < .0001). When patients were sorted according to the severity of cirrhosis, mean survival times in PEI and OLT patients were 67 and 80 months in CTP class A (P = .05), 38 and 90 months in class B (P < .0001), and 31 and 95 months in class C (P = .0004). Similarly, mean tumor-free survival times in the 2 series of patients were 49 and 98 months in CTP class A (P < .0001), 39 and 121 months in class B (P < .0001), and 35 and 139 months in class C (P < .0001). In conclusion, this study challenges the therapeutic efficacy of PEI for patients with cirrhosis and early HCC, when compared to OLT: the proportion of both long-term survivors and tumor-free survivors was increased by OLT over PEI. The benefit of OLT extends to all patients, regardless of the degree of liver impairment. (Liver Transpl 2004;10:1355-1363.)
Posttransplant survival in pediatric fulminant hepatic failure: The SPLIT experience
Authors: Baliga Prabhakar , Alvarez Sergio , Lindblad Anne , Zeng Lan
Published: October 2004

Pediatric patients with fulminant hepatic failure (FHF) tend to be the sickest and have the most urgent need for a liver transplant. The purpose of this analysis was to identify factors associated with posttransplant survival in this subset of patients. Data on all FHF patients registered in the Studies of Pediatric Liver Transplantation (SPLIT) registry from 1995 to 2002 were analyzed. Demographics such as age, gender, race, weight, and etiology of liver disease were recorded. Pretransplant degree of encephalopathy; intubation; dialysis; laboratory parameters such as serum bilirubin and international normalized ratio of coagulopathy (INR); and type of graft: cadaveric whole, cadaveric technical variant, or living donor were analyzed to determine effects on patient survival. Overall, FHF accounted for 12.9% (141 / 1,092) of primary transplants performed between 1995 and 2002. The etiology of liver disease was unknown in the vast majority of children (126 / 141; 89.4%). Mortality while on the waiting list for FHF children is significantly higher than for children with other liver disease (P < .0001). Six-month survival posttransplant for patients with FHF (74.5%) is significantly lower (P < .0001) than those with chronic liver disease (88.9%). A multivariate model demonstrates that the highest risk group includes those children with grade 4 encephalopathy (P < .0001), infants less than 1 year of age (P = .018), and children requiring dialysis prior to transplantation (P = .002). Pretransplant bilirubin and INR were not significant predictors of posttransplant survival after controlling for the other significant factors. Living donor and split / reduced grafts did not have a significantly increased risk of posttransplant death compared to whole grafts. In conclusion, despite advances in the surgical techniques and changes in organ allocation, pediatric patients with FHF continue to have a high pretransplant mortality and less successful posttransplant survival compared to children with chronic liver disease. (Liver Transpl 2004;10:1364-1371.)
Preoperative evaluation of biliary anatomy in adult live liver donors with volumetric mangafodipir trisodium enhanced magnetic resonance cholangiography
Authors: Ayuso Juan R. , Ayuso Carmen , Bombuy Ernest , De Juan Carmen , Llovet Josep M. , De Caralt Teresa M. , Sánchez Marcel , Pagés Mario , Bruix Jordi , García-Valdecasas Juan C.
Published: October 2004

Accurate preoperative depiction of biliary anatomy is not always adequately accomplished by imaging techniques in living donor liver transplantation (LDLT). We present the results of a prospective study designed to evaluate the ability of mangafodipir trisodium (Mn-DPDP)-enhanced magnetic resonance (MR) cholangiography (MRC) for this purpose in a series of 25 adult living liver donors (LLDs). We also analyze if a simple or a more complex surgical procedure can be preoperatively suggested for biliary reconstruction in the recipients. Findings on MRC were compared with operative cholangiography (OC). A conventional distribution with a right hepatic duct (RHD) longer than 1 cm anticipated a simple procedure (duct-to-duct anastomosis or hepaticojejunostomy [HJ]). A shorter RHD or any variant were predictors of a more complex surgery (bench ductoplasty or multiple anastomoses). Agreement between MRC and OC in assessing the biliary anatomy was measured using the κ statistic, and differences between the kind of surgery predicted at MRC and the biliary anastomosis performed were evaluated with Fisher’s exact test. Normal variants were present in 16 / 25 donors (64%). MRC was accurate in depicting the pattern of bile duct distribution observed at OC in 22 / 25 (88%) donors (κ = .831), and correctly predicted the complexity of biliary anastomosis in the recipient in 22 / 25 (88%) donors. No significant differences were observed between complexity of biliary surgery proposed at MRC and the final surgery performed (P = .002). In conclusion, Mn-DPDP-enhanced MRC is highly accurate in depicting the biliary duct anatomy and can be used preoperatively for surgical planning in LDLT. (Liver Transpl 2004;10:1391-1397.)
Liver transplantation outcomes for early-stage hepatocellular carcinoma: Results of a multicenter study
Authors: Leung Jessica Y. , Zhu Andrew X. , Gordon Fredric D. , Pratt Daniel S. , Mithoefer Abigail , Garrigan Kathryn , Terella Adam , Hertl Martin , Cosimi Benedict A. , Chung Raymond T.
Published: October 2004

The incidence of hepatocellular carcinoma (HCC), a frequent and incurable complication of cirrhosis, continues to rise. Orthotopic liver transplantation (OLT) has been proposed as a treatment for unresectable, intrahepatic HCC limited in extent to the Milan criteria adopted by the United Network of Organ Sharing (UNOS) in 1998. More recently, somewhat less restrictive University of California, San Francisco (UCSF)10, criteria were proposed. To examine the long-term outcomes of OLT for HCC patients and to assess the UNOS policy of assigning weighted allocation points to patients with HCC, we retrospectively analyzed 144 patients (113 after 1998) with HCC who underwent OLT over an 11-year period at 3 institutions from UNOS Region 1. We compared their outcomes with 525 patients (272 after 1998) who underwent OLT for nonmalignant liver disease. The 1- and 5-year survival rates were 80.3% and 46.7%, respectively, for patients with HCC and 81.5% and 70.6%, respectively, for patients without HCC (P = .020). However, there was no difference in survival between HCC and non-HCC patients after implementation of disease-specific allocation for HCC in 1998. A higher proportion of the HCC cohort was older and male and had chronic HCV infection and alcoholic liver disease. In univariate analysis, having alpha-fetoprotein (AFP) levels of 10 ng/mL or less and meeting clinical and pathologic UCSF criteria were each significant predictors of improved survival (P = .005, P = .02, and P = .03, respectively). AFP greater than 10 ng/mL and exceeding pathologic UCSF criteria were also significant predictors of recurrence (P = .003 and P = .02, respectively). In conclusion, taken together, our data suggest that OLT is an acceptable option for patients with early HCC and that UCSF criteria predict outcome better than Milan or UNOS criteria. Regardless of which criteria are adopted to define eligibility, strict adherence to the criteria is important to achieve acceptable outcomes. (Liver Transpl 2004;10:1343-1354.)
Biological Natural Retting for Determining the Hierarchical Structuration of Banana Fibers
Authors: Gañán Piedad , Zuluaga Robin , Velez Juan Manuel , Mondragon Iñaki
Published: October 2004

Summary: Extraction processes of natural fibers can be performed by different procedures that include mechanical, chemical and biological methods. Each method presents different advantages or drawbacks according to the amount of fiber produced or the quality and properties of fiber bundles obtained. In this study, biological natural retting was satisfactorily used for obtaining banana fibers from plant bunches. However, the most important contribution of this work refers to the description of the hierarchical microstructural ordering present in banana fiber bundles in both bundle surface and inner region. The chemical composition of banana fiber bundles has been evaluated by FTIR spectroscopy. Through exposure time, the fiber bundle configuration presents small variations in composition. The main changes are related to hemicellulose and pectins as they conform the outer walls of the bundle. Hierarchical helicoidal ordering in the bundle surface as well as orientation on the longitudinal axis of the bundle were observed by optical microscopy (OM) and scanning electron microscopy (SEM) for 3–4 μm surface fibers and 10–15 μm inner elementary fibers, respectively. With increasing exposure time, fiber bundle walls lose integrity, as reflected in their mechanical behavior.

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Gluconic Acid Production in Bioreactor with Immobilized Glucose Oxidase Plus Catalase on Polymer Membrane Adjacent to Anion‐Exchange Membrane
Authors: Godjevargova Tzonka , Dayal Rajeshwar , Turmanova Sevdalina
Published: October 2004

Summary: Gluconic acid was obtained in the permeate side of the bioreactor with glucose oxidase (GOD) immobilized onto anion‐exchange membrane (AEM) of low‐density polyethylene grafted with 4‐vinylpiridine. The electric resistance of the anion‐exchange membranes was increased after the enzyme immobilization on the membrane. The gluconic acid productions were relatively low with the GOD immobilized by any method on the AEM. To increase the enzyme reaction efficiency, GOD was immobilized on membrane of AN copolymer (PAN) adjacent to an anion‐exchange membrane in bioreactor. Uses of anion‐exchange membrane led to selective removal of the gluconic acid from the glucose solution and reduce the gluconic acid inhibition. The amount of gluconic acid obtained in the permeate side of the bioreactor with the GOD immobilized on the PAN membrane adjacent to the AEM under electrodialysis was about 30 times higher than that obtained with enzyme directly bound to the AEM. The optimal substrate concentration in the feed side was found to be about 1 g/l. Further experiments were carried out with the co‐immobilized GOD plus Catalase (CAT) on the PAN membrane adjacent to the AEM to improve the efficiency of the immobilize system. The yield of this process was at least 95%. The storage stability of the co‐immobilized GOD and CAT was studied (lost 20% of initial activity for 90 d). The results obtained clearly showed the higher potential of the dual membrane bioreactor with GOD plus CAT bound to ultrafiltration polymer membrane adjacent to the AEM.

Storage stability of GOD activity in GOD plus CAT immobilized on PAN//AEM membranes [♦] and on AEM [▴].

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Storage stability of GOD activity in GOD plus CAT immobilized on PAN//AEM membranes [♦] and on AEM [▴].