bluuebunny/crossref_metadata_2025 huggingface dataset:
Audit Labor Usage and Fees under Business Risk Auditing
Authors: BELL TIMOTHY B. , DOOGAR RAJIB , SOLOMON IRA
Published: July 2008

The adoption of business risk audit (BRA) approaches during the 1990s by several leading audit firms has been the subject of considerable scrutiny and commentary. Under BRA, the auditor responds to the increasing complexity of auditee financial reports by acquiring a deep and comprehensive understanding of the auditee's industry, strategy, business models, and processes—tasks best accomplished by higher‐ranked labor—and by employing this understanding to make audit labor allocations. Using proprietary data for 165 audits conducted in 2002, we investigate three propositions about audit labor use under BRA. First, relative to pre‐BRA benchmarks for the same auditor, we expect BRA audits to use a greater proportion of higher‐ranked labor. Second, we expect engagements with high assessed auditor business risk (ABR), a summary risk assessment that reflects the BRA auditor's rich understanding of the auditee, to be allocated more labor and more higher‐ranked labor than pre‐BRA benchmarks. Third, at all ranks of labor, we expect a positive association between assessed ABR and levels of labor use. We find empirical evidence consistent with these propositions. We also find that total labor use in our sample is only modestly lower than pre‐BRA norms. Analysis of fee data from these engagements suggests that audit fees in 2002 are substantially less than would be expected under pre‐BRA benchmarks. After controlling for audit labor use, both total fees and fees per hour increase with assessed ABR for first‐year auditees but not for continuing auditees. Overall, our results provide evidence on the impact of the BRA audit regime and speak to the likely impact of BRA on audit effectiveness and efficiency.
Earnings Volatility, Cash Flow Volatility, and Informed Trading
Authors: JAYARAMAN SUDARSHAN
Published: July 2008

I examine whether earnings that are smoother or more volatile than cash flows provide or garble information. Consistent with theories that predict more informed trading when public information is less informative, I find that bid‐ask spreads and the probability of informed trading are higher both when earnings are smoother than cash flows and also when earnings are more volatile than cash flows. Additional tests suggest that managers' discretionary choices that lead to smoother or more volatile earnings than cash flows garble information, on average. However, I find that informed trading is attenuated in settings in which theory suggests that discretionary smoothing or volatizing of earnings is likely to be informative.
The Effect of Regulation FD on Transient Institutional Investors' Trading Behavior
Authors: KE BIN , PETRONI KATHY R. , YU YONG
Published: July 2008

We assess the impact of Regulation Fair Disclosure (Reg FD) on the trading behavior of transient institutional investors in the quarter prior to a bad news break in a string of consecutive earnings increases. Bad news breaks are defined as breaks that are by growth firms, preceded by longer strings of consecutive earnings increases, followed by longer strings of consecutive earnings decreases, and associated with larger declines in earnings. Pre–Reg FD transient institutions have abnormal selling of stocks in the quarter immediately preceding a bad news break. This abnormal selling is confined to firms that hold conference calls in the pre–Reg FD period. However, in the post–Reg FD period transient institutions do not exhibit similar abnormal selling of stocks in the quarter before a bad news break. Furthermore, after Reg FD transient institutions allocate less of their stock portfolios to conference call firms relative to non–conference call firms in the quarters prior to a bad news break. These results demonstrate that Reg FD has had an impact on management's selective disclosure behavior and significantly changed the trading behavior of transient institutions.
Does Auditor Reputation Matter? The Case of KPMG Germany and ComROAD AG
Authors: WEBER JOSEPH , WILLENBORG MICHAEL , ZHANG JIEYING
Published: July 2008

We study the stock and audit market effects associated with a widely publicized accounting scandal involving a public company (ComROAD AG) and a large, reputable audit firm (KPMG) in a country (Germany) that has long provided auditors with substantial protection from shareholder legal liability. We use this event to study whether an auditor's reputation helps to ensure audit quality, a rationale for which recent literature and events provide scant support. Given the absence of a strong insurance rationale for audit quality, Germany permits a relatively clean test of whether auditor reputation matters. We find that KPMG's clients sustain negative abnormal returns of 3% at events pertaining to ComROAD, and that these returns are more negative for companies that are likely to have higher demands for audit quality. We also find an increase in the number of clients that drop KPMG in the year of the ComROAD scandal (mostly smaller, recently public companies that are similar to ComROAD). Overall, our results provide support for the reputation rationale for audit quality.
Videogrammetric monitoring of as‐built membrane roof structures
Authors: Lin Shih‐Yuan , Mills Jon P. , Gosling Peter D.
Published: July 2008

A monitoring system that uses applied geomatics techniques, including videogrammetry and terrestrial laser scanning, has been developed in order to investigate the dynamic behaviour of as‐built membrane roof structures. To accommodate the problems involved in measuring such roof structures, examples of which include uniform surface texture and unreachable height, the system adopts a non‐contact targeting methodology to substitute for traditional control techniques. In‐house software was developed for processing the acquired video imagery in order to produce a sequential surface model of the membrane. This paper firstly reports on experiments conducted to demonstrate that the monitoring system was capable of measuring representative test structures with a precision of better than ±1 mm. To prove the feasibility and transferability of the system, videogrammetric monitoring campaigns were subsequently performed at a real‐world test site where two different types of membrane structure were observed. The sequential 3D surface models that were generated allowed the displacement of the membrane surfaces to be investigated over a period, during which the range of the movement reached over 20 mm. The information acquired from the system is proving to be of great value to structural engineers involved in research and development of such membrane structures.
Captive Breeding, Reintroduction, and the Conservation of Amphibians
Authors: GRIFFITHS RICHARD A. , PAVAJEAU LISSETTE
Published: July 2008

Abstract:  The global amphibian crisis has resulted in renewed interest in captive breeding as a conservation tool for amphibians. Although captive breeding and reintroduction are controversial management actions, amphibians possess a number of attributes that make them potentially good models for such programs. We reviewed the extent and effectiveness of captive breeding and reintroduction programs for amphibians through an analysis of data from the Global Amphibian Assessment and other sources. Most captive breeding and reintroduction programs for amphibians have focused on threatened species from industrialized countries with relatively low amphibian diversity. Out of 110 species in such programs, 52 were in programs with no plans for reintroduction that had conservation research or conservation education as their main purpose. A further 39 species were in programs that entailed captive breeding and reintroduction or combined captive breeding with relocations of wild animals. Nineteen species were in programs with relocations of wild animals only. Eighteen out of 58 reintroduced species have subsequently bred successfully in the wild, and 13 of these species have established self‐sustaining populations. As with threatened amphibians generally, amphibians in captive breeding or reintroduction programs face multiple threats, with habitat loss being the most important. Nevertheless, only 18 out of 58 reintroduced species faced threats that are all potentially reversible. When selecting species for captive programs, dilemmas may emerge between choosing species that have a good chance of surviving after reintroduction because their threats are reversible and those that are doomed to extinction in the wild as a result of irreversible threats. Captive breeding and reintroduction programs for amphibians require long‐term commitments to ensure success, and different management strategies may be needed for species earmarked for reintroduction and species used for conservation research and education.
Ecological and Economic Services Provided by Birds on Jamaican Blue Mountain Coffee Farms
Authors: KELLERMANN JHERIME L. , JOHNSON MATTHEW D. , STERCHO AMY M. , HACKETT STEVEN C.
Published: July 2008

Abstract:  Coffee farms can support significant biodiversity, yet intensification of farming practices is degrading agricultural habitats and compromising ecosystem services such as biological pest control. The coffee berry borer (Hypothenemus hampei) is the world's primary coffee pest. Researchers have demonstrated that birds reduce insect abundance on coffee farms but have not documented avian control of the berry borer or quantified avian benefits to crop yield or farm income. We conducted a bird‐exclosure experiment on coffee farms in the Blue Mountains, Jamaica, to measure avian pest control of berry borers, identify potential predator species, associate predator abundance and borer reductions with vegetation complexity, and quantify resulting increases in coffee yield. Coffee plants excluded from foraging birds had significantly higher borer infestation, more borer broods, and greater berry damage than control plants. We identified 17 potential predator species (73% were wintering Neotropical migrants), and 3 primary species composed 67% of migrant detections. Average relative bird abundance and diversity and relative resident predator abundance increased with greater shade‐tree cover. Although migrant predators overall did not respond to vegetation complexity variables, the 3 primary species increased with proximity to noncoffee habitat patches. Lower infestation on control plants was correlated with higher total bird abundance, but not with predator abundance or vegetation complexity. Infestation of fruit was 1–14% lower on control plants, resulting in a greater quantity of saleable fruits that had a market value of US$44–$105/ha in 2005/2006. Landscape heterogeneity in this region may allow mobile predators to provide pest control broadly, despite localized farming intensities. These results provide the first evidence that birds control coffee berry borers and thus increase coffee yield and farm income, a potentially important conservation incentive for producers.
Interspecific Patterns of Genetic Diversity in Birds: Correlations with Extinction Risk
Authors: EVANS SIMON R. , SHELDON BEN C.
Published: July 2008

Abstract: Birds are frequently used as indicators of ecosystem health and are the most comprehensively studied class in the animal kingdom. Nevertheless, a comprehensive, interspecific assessment of the correlates of avian genetic diversity is lacking, even though indices of genetic diversity are of considerable interest in the conservation of threatened species. We used published data on variation at microsatellite loci from 194 bird species to examine correlates of diversity, particularly with respect to conservation status and population size. We found a significant decline in mean heterozygosity with increasing extinction risk, and showed, by excluding species whose heterozygosity values were calculated with heterospecific primers, that this relationship was not dependent on ascertainment bias. Results of subsequent regression analyses suggested that smaller population sizes of threatened species were largely responsible for this relationship. Thus, bird species at risk of extinction are relatively depauperate in terms of neutral genetic diversity, which is expected to make population recovery more difficult if it reflects adaptive genetic variation. Conservation policy will need to minimize further loss of diversity if the chances of saving threatened species are to be maximized.
Impacts of Chronic Anthropogenic Noise from Energy‐Sector Activity on Abundance of Songbirds in the Boreal Forest
Authors: BAYNE ERIN M. , HABIB LUCAS , BOUTIN STAN
Published: July 2008

Abstract: The effects of human activities in forests are often examined in the context of habitat conversion. Changes in habitat structure and composition are also associated with increases in the activity of people with vehicles and equipment, which results in increases in anthropogenic noise. Anthropogenic noise may reduce habitat quality for many species, particularly those that rely on acoustic signals for communication. We compared the density and occupancy rate of forest passerines close to versus far from noise‐generating compressor stations and noiseless well pads in the boreal forest of Alberta, Canada. Using distance‐based sampling, we found that areas near noiseless energy facilities had a total passerine density 1.5 times higher than areas near noise‐producing energy sites. The White‐throated Sparrow (Zonotrichia albicollis), Yellow‐rumped Warbler (Dendroica coronata), and Red‐eyed Vireo (Vireo olivaceus) were less dense in noisy areas. We used repeat sampling to estimate occupancy rate for 23 additional species. Seven had lower conditional or unconditional occupancy rates near noise‐generating facilities. One‐third of the species examined showed patterns that supported the hypothesis that abundance is influenced by anthropogenic noise. An additional 4 species responded negatively to edge effects. To mitigate existing noise impacts on birds would require approximately $175 million. The merits of such an effort relative to other reclamation actions are discussed. Nevertheless, given the $100 billion energy‐sector investment planned for the boreal forest in the next 10 years, including noise suppression technology at the outset of construction, makes noise mitigation a cost‐effective best‐management practice that might help conserve high‐quality habitat for boreal birds.
A review of fibroblast‐populated collagen lattices
Authors: Dallon John C. , Ehrlich H. Paul
Published: July 2008

Bell's introduction of the fibroblast‐populated collagen lattice (FPCL) has facilitated the study of collagen–cell interactions. As a result of the numerous modifications of the casting of FPCLs, the in vivo applications of these in vitro findings have been confusing. Here experimental FPCL contraction findings are viewed in regard to three proposed mechanisms responsible for lattice contraction. The cellular mechanisms responsible for generating FPCL contraction are cell contraction, cell tractional forces related to cell locomotion, and initial cell elongation and spreading.
Local therapy and treatment costs of chronic, venous leg ulcers with electrical stimulation (Dermapulse®): A prospective, placebo controlled, double blind trial
Authors: Jünger Michael , Arnold Andreas , Zuder Daniel , Stahl Hans‐Werner , Heising Susanna
Published: July 2008

The purpose of our study was the evaluation of the therapeutic benefit and the economical profit of low‐frequency pulsed current applied to therapy‐resistant venous leg ulcers. We investigated 39 patients in a prospective, placebo‐controlled, double blind study on the effect of low‐frequency pulsed current (Dermapulse®) on healing in chronic venous ulcers during a 4‐month course of treatment. All patients had chronic venous ulcers. The following criteria were recorded: ulcer size, pain, capillary density, and transcutaneous oxygen partial pressure. In verum group 3, ulcers healed and ulcer area was reduced significantly. In placebo group two ulcers healed. Ulcer size was reduced significantly in each group (paired test), the difference of ulcer area reduction between the “verum” and the placebo group (unpaired test) was not significant. Capillary density in the ulcer increased in both groups. In verum group, electrical stimulation led to rapid and lasting reduction of pain (unpaired test, p=0.049). By means of the process calculation method for the subgroup of outpatients this treatment method was economically effective. Electrical stimulation seems to be a viable treatment option for therapy‐resistant venous leg ulcers.
The altered expression of syndecan 4 in the uninvolved skin of venous leg ulcer patients may predispose to venous leg ulcer
Authors: Nagy Nikoletta , Németh István Balázs , Szabad Gábor , Szolnoky Gyõzõ , Belsõ Nóra , Bata‐Csörgõ Zsuzsanna , Dobozy Attila , Kemény Lajos , Széll Márta
Published: July 2008

Syndecan 4 (SDC4), a heparan sulfate proteoglycan, and neuropilin 1 (NRP1), a transmembrane receptor, are both involved in normal wound healing, but little is known about their possible role in venous leg ulcer pathogenesis. We aimed to investigate whether there are any expression abnormalities and/or gene polymorphisms of SDC4 and NRP1 associated with venous leg ulcer. SDC4 showed significantly lower mRNA and protein expression in the uninvolved dermis of venous leg ulcer patients (n=15) compared with controls (n=15; p=0.0136), while NRP1 showed no expression abnormalities. None of the examined SDC4 and NRP1 polymorphisms showed a difference in their allelic distribution between leg ulcer patients (n=92) and controls (n=92). We hypothesize that SDC4 may play an essential role not only in the inflammation and tissue formation phases of normal wound healing, but its expression abnormalities observed in the uninvolved dermis of venous leg ulcer patients may contribute to venous leg ulcer development.
Hyperbaric oxygen attenuates cell growth in skin fibroblasts cultured in a high‐glucose medium
Authors: Lin Hen‐I , Chu Shi‐Jye , Perng Wann‐Cherng , Wu Chin‐Pyng , Lin Zuei‐Yin , Huang Kun‐Lun
Published: July 2008

Hyperglycemia and hypoxia synergistically retard diabetic wound healing. We investigated the direct effect of hyperbaric and normobaric hyperoxia on skin fibroblasts cultured in a high‐glucose medium. Detroit 551 human dermal fibroblasts cultured in Dulbecco's modified Eagle's medium containing d‐glucose had reduced cell survival compared with cells grown in normal glucose medium; survival was 27.5±3.8% lower in 25 mM glucose and 30.6±3.7% lower in 50 mM glucose. Cell survival decreased because of inhibition of cell proliferation and enhanced cell death. Daily hyperbaric oxygen therapy at 2.5 atmosphere absolute for 90 minutes on 3 consecutive days reduced cell proliferation and increased cell death in normal cultured fibroblasts. Hyperbaric oxygen therapy and high‐glucose medium had a synergistic effect and reduced survival by 37.6±4.4% (25 mM glucose) and 39.6±5.1% (50 mM glucose). The effects of hyperbaric oxygen and high‐glucose medium were associated with overproduction of reactive oxygen species. Our results suggest that direct exposure of skin fibroblasts to hyperbaric oxygen affects cell growth and superimposes the toxic effect of high glucose. This cytotoxicity may be related to the production of reactive oxygen species in the fibroblasts.
Healing of a porcine burn wound dressed with human and bovine amniotic membranes
Authors: Park Mushik , Kim Sungpo , Kim In Seop , Son Daegu
Published: July 2008

The effects of amniotic membranes (AMs), either fresh human and bovine AMs or acellular bovine AMs, on wound healing were compared among the burn wounds of porcine skin. Six pigs were chosen for the study, and we created deep second‐degree contact burns on them with a digitally controlled aluminum thermal block. Then we applied the dressings to some of the wounds using fresh human and bovine AMs, acellular bovine AMs, polyurethane foam, or no dressing. We evaluated the pigs for (1) the rate of epithelialization, (2) histological grading, and (3) infections. We found that the AM groups showed better wound‐healing effects than did the polyurethane foam and no dressing groups, and these differences were statistically significant. However, the differences between the AM groups were not statistically significant. Wound cultures showed higher infection rates in the control and polyurethane foam groups compared with the other groups. Our study showed that fresh or acellular bovine AMs provided similar efficacy for wound healing as did the fresh human AMs.
Expression of genes encoding antimicrobial proteins and members of the toll‐like receptor/nuclear factor‐κB pathways in engineered human skin
Authors: McFarland Kevin L. , Klingenberg Jennifer M. , Boyce Steven T. , Supp Dorothy M.
Published: July 2008

Skin functions as a first line of defense against microbial invasion. Tissue‐engineered cultured skin substitutes (CSS) are used to aid wound closure in massively burned patients, and have been used to facilitate safe and effective wound closure in adult patients with chronic wounds. Although they contain only two cell types at grafting, they can potentially contribute to innate defense against pathogens and stimulation of adaptive immunity. Gene microarrays were used to identify expression in cultured skin of genes involved in innate and adaptive immune responses, and to evaluate the effects of cytokine stimulation on expression levels. Cultured skin expressed multiple antimicrobial protein genes, including human β defensins 1 and 2 and S100A12. In addition, the antiviral gene APOBEC3G, which was not previously identified in skin, was expressed in CSS and up‐regulated by interleukin‐1α and tumor necrosis factor α. Cathelicidin was not expressed in unstimulated CSS, but was induced by cytokine treatment. Further, genes encoding several proinflammatory cytokines and members of the toll‐like receptor and nuclear factor κ B pathways were expressed in CSS, suggesting that cells in CSS can mediate activation of inflammatory responses. The observed expression patterns indicate that engineered human skin utilizes innate defense mechanisms similar to those reported for native skin. Therefore, regulation of these pathways by cytokine stimulation may offer a mechanism for increasing innate immunity in CSS to combat wound infection after grafting onto patients.
Basic fibroblast growth factor (bFGF) alleviates the scar of the rabbit ear model in wound healing
Authors: Xie Ju Lin , Bian Hui Ning , Qi Shao Hai , Chen Hua De , Li Hou Dong , Xu Ying Bin , Li Tian Zeng , Liu Xu Sheng , Liang Hui Z. , Xin Bang Rong , Huan Yong
Published: July 2008

Studies suggest a possible antiscarring effect of basic fibroblast growth factor (bFGF) during wound healing. However, little is known about the precise pathological mechanisms of bFGF. In particular, there is only limited information available about the mechanism of exogenous administration of bFGF to scar formation. To investigate the effect of bFGF on the hypertrophic scar in the rabbit ear model and to clarify the mechanisms of bFGF on treatment for scar in wound healing, the rabbit ear model of wound healing was created and treated topically with bFGF once daily for 3 months; then we examined the changes of macroscopic and histopathological characteristics of scars and the expression of collagen and collagenase‐1 (matrix metalloproteinase‐1). The results of macroscopic and histologic characteristics revealed a significant difference between scars treated with bFGF and control scars. The expression of collagen in the scars treated with bFGF was decreased, as compared with the scars treated with saline. Further study revealed that bFGF could remarkably enhance expression of matrix metalloproteinase‐1. bFGF could improve the quality of wound healing and remarkably alleviate the scar in the rabbit ear model in wound healing, which suggests that bFGF exerted a net negative effecton scar formation in wound healing. The evidence should contribute to a better understanding of the biological activities of bFGF during hypertrophic scar formation.
NON‐CORONARY HEART DISEASE IN DIALYSIS PATIENTS: Sudden Cardiac Death and Dialysis Patients
Authors: Herzog Charles A. , Mangrum J. Michael , Passman Rod
Published: July 2008

Dialysis patients have extraordinarily high mortality rates. The death rate for all US dialysis patients in 2004 was 230 per 1000 patient‐years. Cardiac disease is the major cause of death in dialysis patients and accounts for 43% of all‐cause mortality. In the United States Renal Data System database 62% of cardiac deaths (or 27% of all deaths) are attributable to arrhythmic mechanisms. The estimated rate of sudden cardiac death in US dialysis patients in 2002 was 7% per year. There are several plausible explanations for the special vulnerability of dialysis patients to sustaining sudden cardiac death. Obstructive coronary artery disease, coupled with diminished tolerance to myocardial ischemia (in the setting of myocardial fibrosis and left ventricular hypertrophy), rapid electrolyte shifts in hemodialysis patients, and derangements in autonomic function may all contribute to this heightened risk of sudden cardiac death. This review focuses on the epidemiology of sudden cardiac death in dialysis patients, underlying mechanisms of sudden death, and potential interventions to reduce the risk of sudden cardiac death in dialysis patients (including medical therapy and defibrillators). It is unlikely that one single therapeutic intervention will prevent sudden cardiac death in dialysis patients; but a more modest (and attainable) goal is the implementation of multiple strategies to reduce the risk of sudden cardiac death in this special high‐risk population.
Wound‐healing Gene Family Expression Differences Between Fetal and Foreskin Cells Used for Bioengineered Skin Substitutes
Authors: Hirt‐Burri Nathalie , Scaletta Corinne , Gerber Stefan , Pioletti Dominique P. , Applegate Lee Ann
Published: July 2008

Abstract:  For tissue engineering, several cell types and tissues have been proposed as starting material. Allogenic skin products available for therapeutic usage are mostly developed with cell culture and with foreskin tissue of young individuals. Fetal skin cells offer a valuable solution for effective and safe tissue engineering for wounds due to their rapid growth and simple cell culture. By selecting families of genes that have been reported to be implicated in wound repair and particularly for scarless fetal wound healing including transforming growth factor‐beta (TGF‐β) superfamily, extracellular matrix, and nerve/angiogenesis growth factors, we have analyzed differences in their expression between fetal skin and foreskin cells, and the same passages. Of the five TGF‐β superfamily genes analyzed by real‐time reverse transcription–polymerase chain reaction, three were found to be significantly different with sixfold up‐regulated for TGF‐β2, and 3.8‐fold for BMP‐6 in fetal cells, whereas GDF‐10 was 11.8‐fold down‐regulated. For nerve growth factors, midkine was 36‐fold down‐regulated in fetal cells, and pleiotrophin was 4.76‐fold up‐regulated. We propose that fetal cells present technical and therapeutic advantages compared to foreskin cells for effective cell‐based therapy for wound management, and overall differences in gene expression could contribute to the degree of efficiency seen in clinical use with these cells.
Transplantation of Meniscus Regenerated by Tissue Engineering With a Scaffold Derived From a Rat Meniscus and Mesenchymal Stromal Cells Derived From Rat Bone Marrow
Authors: Yamasaki Takuma , Deie Masataka , Shinomiya Rikuo , Yasunaga Yuji , Yanada Shinobu , Ochi Mitsuo
Published: July 2008

Abstract:  The purpose of this study was to assess transplantation of regenerated menisci using scaffolds from normal allogeneic menisci and bone‐marrow‐derived mesenchymal stromal cells (BM‐MSCs) of rats. We reported that scaffolds derived from normal menisci seeded with BM‐MSCs in vitro could form meniscal tissues within 4 weeks. Then, we hypothesized that our tissues could be more beneficial than allogeneic menisci regarding early maturation and chondroprotective effect. Bone marrow was aspirated from enhanced green fluorescent protein transgenic rats. BM‐MSCs were isolated and seeded onto scaffolds which were prepared from Sprague–Dawley rat menisci. After 4 weeks in coculture, the tissues were transplanted to the defect of menisci. Repopulation of BM‐MSCs and expression of extracellular matrices were observed in the transplanted tissues at 4 weeks after surgery. At 8 weeks, articular cartilage in the cell‐free group was more damaged compared to that in the cell‐seeded group or the meniscectomy group.
Thermodynamic Considerations in Solid Adsorption of Bound Solutes for Patient Support in Liver Failure
Authors: Patzer II John F.
Published: July 2008

Abstract:  New detoxification modes of treatment for liver failure that use solid adsorbents to remove toxins bound to albumin in the patient bloodstream are entering clinical evaluations, frequently in head‐to‐head competition. While generally effective in reducing toxin concentration beyond that obtainable by conventional dialysis procedures, the solid adsorbent processes are largely the result of heuristic development. Understanding the principles and limitations inherent in competitive toxin binding, albumin versus solid adsorbent, will enhance the design process and, possibly, improve detoxification performance. An equilibrium thermodynamic analysis is presented for both the molecular adsorbent recirculating system (MARS) and fractionated plasma separation, adsorption, and dialysis system (Prometheus), two advanced systems with distinctly different operating modes but with similar equilibrium limitations. The Prometheus analysis also applies to two newer approaches: sorbent suspension reactor and microsphere‐based detoxification system. Primary results from the thermodynamic analysis are that: (i) the solute–albumin binding constant is of minor importance to equilibrium once it exceeds about 105 L/mol; (ii) the Prometheus approach requires larger solid adsorbent columns than calculated by adsorbent solute capacity alone; and (iii) the albumin‐containing recycle stream in the MARS approach is a major reservoir of removed toxin. A survey of published results indicates that MARS is operating under mass transfer control dictated by solute–albumin equilibrium in the recycle stream, and Prometheus is approaching equilibrium limits under current clinical protocols.
Recovering the Reptile Community after the Mine‐Tailing Accident of Aznalcóllar (Southwestern Spain)
Authors: Márquez‐Ferrando Rocío , Pleguezuelos Juan M. , Santos Xavier , Ontiveros Diego , Fernández‐Cardenete Juan R.
Published: July 2008

Ecosystem restoration requires that habitat requirements of all species be considered. Among animal communities in Mediterranean ecosystems, reptiles, as ectothermic vertebrates, need refuges for avoidance of extreme environmental temperatures, concealment from predators, and oviposition sites. In 1998, a massive amount of tailings broke out of the holding pond of the Aznalcóllar mine (southwestern Spain) and polluted the Guadiamar river valley. After the accident, a soil‐ and vegetation restoration program began, and the Guadiamar Green Corridor was created to connect two huge natural areas, Doñana National Park and the Sierra Morena. Within this corridor, the reptile community remained dramatically impoverished, probably because of elimination of all natural refuges during the soil restoration program. To test this hypothesis, we set an array of artificial refuges (logs) in a large experimental plot. During the 5 years of the experiment (2002–2006), the area managed with artificial refuges exhibited a better and faster recovery of the reptile community in species richness and individual abundance than did the control area with no artificial refuges. Moreover, reptile colonization of the Guadiamar Green Corridor was transverse rather than lineal—that is, it did not act as a corridor for reptiles, at least in the first stages of colonization. This suggests that landscape restoration programs should not neglect refuge availability, a limiting resource for reptile species.
The Effects of Flavonoid Allelochemicals from Knapweeds on Legume–Rhizobia Candidates for Restoration
Authors: Alford Élan R. , Vivanco Jorge M. , Paschke Mark W.
Published: July 2008

Russian knapweed (Acroptilon repens) and Spotted knapweed (Centaurea maculosa) are allelopathic weeds invasive in North American grasslands. Both species contain at least one phytotoxic flavonoid root exudate with demonstrated negative influences on other plants. Previous findings indicated that Silky lupine (Lupinus sericeus), among other legumes, was relatively resistant to Spotted knapweed invasion and allelochemistry. We hypothesized that legume species may exhibit resistance to flavonoids in knapweed root exudates and may serve as candidate species for management efforts. Because legumes form symbiotic relationships with rhizobia, these bacteria must also be evaluated for allelochemical resistance before legumes can be recommended for restoration. In this study, we examined four legume species for effects of 7,8‐benzoflavone (from Russian knapweed) and (±)‐catechin (from Spotted knapweed) on rhizosphere interactions involving legume roots and associated rhizobia. Pure cultures of four rhizobia strains exhibited varied responses when grown with 7,8‐benzoflavone or (±)‐catechin. Alfalfa (Medicago sativa) and its bacterial symbiont, Sinorhizobium meliloti, exhibited allelochemical resistance that varied with (±)‐catechin concentration when grown in vitro. Four legume species were grown under greenhouse conditions. Plants that were inoculated and nodulated generally exhibited no response to 7,8‐benzoflavone or (±)‐catechin treatments. Plants that were not inoculated exhibited stronger responses. Therefore, inoculation and nodulation may confer resistance to allelochemicals. These results, when coupled with previous research and field observations, suggest that legumes may not be susceptible to knapweed allelopathy and may be good choices in restoration of knapweed infestations when inoculated, particularly on sites with low soil nitrogen.
Evaluation of Restoration Measures in a Shallow Lake through a Comparison of Present Day Zooplankton Communities with Historical Samples
Authors: Louette Gerald , Declerck Steven , Vandekerkhove Jochen , De Meester Luc
Published: July 2008

Many shallow lakes have lost a large part of their ecological value during the past decades. Human‐induced factors such as eutrophication and inappropriate fish stock management are generally the main causes for this loss. To restore such degraded habitats, several measures are taken, typically involving a reduction of nutrient loading and interventions in the aquatic food web functioning (biomanipulation). In this study, we report on the joint effects of a series of restoration measures in a shallow lake (Lake Kraenepoel, Belgium, 22 ha) and evaluate these effects via three different criteria. The first criterion is that the target condition, being a clearwater phase with submerged macrophytes, was successfully achieved and persisted for a period of at least 5 years after restoration. Second, we detected a substantial change in community structure of cladoceran zooplankton and an associated increase in species richness and conservation value following restoration measures. Finally, we observed that the general structure of the present day cladoceran zooplankton community resembles well that of the preeutrophication period (1929–1931). Current species richness, however, tends to be lower than in the reference period, and some rare species are still lacking. It is conceivable that, when submerged macrophytes develop further, a subset of specialist species may reappear. Overall, the use of historical habitat‐specific samples offers a major opportunity for evaluating restoration success in great detail. Community structures may directly be compared, the gain or loss of specific species can accurately be documented, and more insights in the observed patterns be obtained.
Familial Clustering of Migraine: Further Evidence From a Portuguese Study
Authors: Lemos Carolina , Castro Maria‐José , Barros José , Sequeiros Jorge , Pereira‐Monteiro José , Mendonça Denisa , Sousa Alda
Published: July 2008

Objective.— Our aim was to evaluate familial aggregation of migraine in a large group of Portuguese families, and to assess if familial aggregation differs between MA and MO.

Methods.— Familial aggregation was evaluated by estimating relative risk (RR) of migraine in 143 first‐degree relatives of 50 probands with MA, in 196 first‐degree relatives of 94 probands with MO and also in proband's spouses. Probands were enrolled in the study from a clinical sample and a population sample was used as reference.

Results.— A significantly increased risk of migraine was found in both first‐degree relatives of MO probands (RR = 3.7; 95% CI: 3.2‐4.3) and of MA probands (RR = 3.6; 95% CI: 3.1‐4.3), comparatively to the general population. Risk for spouses was not increased. First‐degree relatives of MA probands and MO probands had a significantly increased risk of both MA and MO compared to the general population. In the group of MA probands, RR of MA in first‐degree relatives reached a significant 4‐fold increase when compared with RR of MO (RRMA|MA = 12.2, 95%CI: 7.7‐19.5; RRMO|MA = 3.1, 95%CI: 2.5‐3.8), while, in the group of MO probands, RR of MA was not significantly increased when compared with RR of MO (RRMA|MO = 5.3, 95%CI: 3.1‐9.2; RRMO|MO = 4.0, 95%CI: 3.5‐4.7).

Conclusions.— The present study focus on familial aggregation of migraine in a Portuguese population. Our results demonstrate a substantial familial risk of migraine with evidence of both common and specific etiologic mechanisms for either migraine subtypes.
Familial Hemiplegic Migraine With Prolonged Aura and Multimodality Imaging: A Case Report
Authors: Kumar Gogi , Topper Leonid , Maytal Joseph
Published: July 2008

We report a case of familial hemiplegic migraine with prolonged aura where multimodality imaging showed hemispheric cytotoxic edema along with evidence of hypometabolism in the affected hemisphere while there was no evidence of hypoperfusion of the affected hemisphere demonstrating that neuronal depression is a more plausible explanation in its pathogenesis.
Headache Disability in Orofacial Pain Patients Is Related to Traumatic Life Events
Authors: Branch Morris A.
Published: July 2008

Background.— Headache is commonly reported in patients presenting with orofacial pain. It has only recently been demonstrated that headache‐related disability is high in orofacial pain patients. Traumatic life events (TLEs) such as sexual abuse, physical abuse, and post‐traumatic stress disorder (PTSD) are also common in orofacial pain patients and in the same patients reporting headache. In association with a previously reported study of headache disability in orofacial pain patients, it was noted that Migraine Disability Assessment (MIDAS) scores appeared to be significantly higher in patients with TLEs.

Objectives.— To investigate the relationship between TLEs and headache disability in a clinic population of orofacial pain patients.

Design.— Retrospective study.

Methods.— Four hundred and twenty‐six consecutive orofacial pain patient records were reviewed, composed of new patients seen at the Orofacial Pain Center, National Naval Medical Center, Bethesda, MD, from November 2003 through December 2004.

Results.— Of 426 orofacial pain patients reporting headache, 109 or 41.7% reported TLEs. In patients with TLEs, the mean MIDAS score was 28.81 ± 37.2 compared with 13.5 ± 17.9 for patients not reporting TLEs P < .000. MIDAS scores were significantly correlated with TLEs, Spearman correlation coefficient 0.272, P < .010.

Conclusions.— This is the first study to demonstrate that headache disability is significantly higher in a group of orofacial pain patients with TLEs and is correlated with that report of traumatic events. These findings clearly demonstrate the necessity for providers to consider a history of TLEs in orofacial pain patients presenting with headache.
Cortical Spreading Edema in Persistent Visual Migraine Aura
Authors: Bereczki Dániel , Kollár József , Kozák Norbert , Viszokay Kornél , Barta Zoltán , Sikula Judit , Magyar Mária Tünde
Published: July 2008

We present imaging evidence of the spreading of cortical edema with reversibly restricted water diffusion from the left occipital to the temporoparietal cortex in persistent visual migraine aura in a 58‐year‐old man. The right‐sided visual field defect lasting for 15 days was associated with discoupling of glucose metabolism and blood flow and the decreased apparent diffusion coefficient also suggested cytotoxic edema. At 8 weeks no signs were present, and magnetic resonance imaging became normal; therefore, long‐lasting restricted cortical water diffusion, even if coupled with hypometabolism and edema, can be reversible in persistent visual migraine aura.
Tornwaldt's Cyst Presenting Only As Occipital Headache: A Case Report
Authors: Cho Hang S. , Byeon Hyung K. , Kim Jun‐Hee , Kim Kyung S.
Published: July 2008

Tornwaldt's cyst (sometimes calledThornwaldt'scyst) is a rare cause of occipital headache. Owing to the rare occurrence of occipital headache as a symptom of Tornwaldt's cyst, if the patient presented only with occipital headache, this clinical symptom may be falsely perceived as a sign of neurologic disease leading to time‐consuming diagnostic examinations that delay the establishment of a correct diagnosis.
Choroid Plexus Dysfunction: The Initial Event in the Pathogenesis of Wernicke’s Encephalopathy and Ethanol Intoxication
Authors: Nixon Peter F. , Jordan Lindsay , Zimitat Craig , Rose Stephen E. , Zelaya Fernando
Published: July 2008

Background:  In both acute ethanol intoxication and in thiamin deficient glucose metabolism, previous studies have detected blood‐brain barrier (BBB) and/or blood‐CSF‐barrier (BCSFB) impairment but were unable to assess their significance in relation to other changes in the brain.

Methods:  Contrast‐enhanced, magnetic resonance imaging (MRI) was used to detect and time any impairment of the BBB or BCSFB in rats given an acute ethanol load or in rats made thiamin deficient to the point of mild ataxia and then given an acute glucose load.

Results:  The BCSFB at the choroid plexus (CP) was impaired within 10 minutes by either (i) a single i.p. dose of glucose in thiamin‐deficiency, an effect that was attenuated by prior MK801 and preceded the published onset of exacerbation of motor incoordination and elevation of brain glutamate derivatives; or (ii) a single i.p. dose of ethanol in thiamin‐sufficiency, an effect that was proportional to the blood alcohol concentration and preceded the published onset of signs of intoxication. In contrast to the BCSFB, the BBB remained intact throughout the 90 minutes period of these experiments.

Conclusions:  In both ethanol intoxication and thiamin‐deficient glucose metabolism, BCSFB impairment exposes the CSF and hence the brain extracellular fluid to neuroactive substances from the blood. CP impairment is the earliest detected event in both these animal models; and explains the paraventricular location of WE neuropathology and why WE is associated with, but not dependent on, alcoholism.
Acute Alcohol Intake Induces SOCS1 and SOCS3 and Inhibits Cytokine‐Induced STAT1 and STAT3 Signaling in Human Monocytes
Authors: Norkina Oxana , Dolganiuc Angela , Catalano Donna , Kodys Karen , Mandrekar Pranoti , Syed Amber , Efros Marian , Szabo Gyongyi
Published: July 2008

Background:  Acute alcohol consumption is associated with induction of immuno‐inhibitory cytokines and down‐regulation of pro‐inflammatory responses to various pathogens. We previously reported that alcohol activates janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling leading to IL‐10 induction. The JAK‐STAT pathway also activates its own negative regulators, suppressors of cytokine signaling (SOCS) 1 and SOCS3. SOCS proteins are inducible inhibitors that negatively regulate STAT3/STAT1 signaling pathways induced by cytokines, IL‐6 or IFNs. Here we aimed to explore the effect of acute alcohol on induction of SOCS1/SOCS3 and regulation of STAT3/STAT1 pathways induced by IL‐6 or IFNs in human monocytes.

Methods:  Blood samples from normal volunteers were collected before and 24 hours after consumption of 2 ml vodka/kg body weight. For in vitro experiments human monocytes were pretreated with ethanol (EtOH) followed by stimulation with cytokines; proteins were analyzed by Western blot, nuclear protein binding to DNA by EMSA, and RNA by real time PCR.

Results:  Acute in vivo or in vitro alcohol treatment increased both SOCS1 and SOCS3 RNA expression in monocytes. Alcohol treatment resulted in increased STAT3 and STAT1 DNA binding capacity. Activation of both STAT1 and STAT3 has been shown to induce SOCS1/3. We hypothesized that induction of SOCS proteins by alcohol in turn may lead to modulation of cytokine signaling through STAT1 and STAT3. Indeed, we observed significant down‐regulation of IL‐6‐, IFNα‐ and IFNγ‐induced STAT1 DNA binding as well as inhibition of IL‐6‐ and IFNγ‐induced STAT3 when alcohol was added to monocytes 3 hours prior to the cytokine stimulation. Consistent with inhibition of IL‐6‐induced STAT3 DNA binding in alcohol‐pretreated cells, the levels of IL‐6‐dependent genes, MCP‐1 and ICAM‐1, was reduced after IL‐6 stimulation. Similar to EtOH alone, combined EtOH+IL‐6 simulation resulted in increased expression of both SOCS3 and SOCS1 genes.

Conclusion:  While acute alcohol treatment alone activates STAT1/3 signaling pathways and induces SOCS3 and SOCS1 levels in monocytes, alcohol also leads to down‐regulation of IL‐6‐, IFNα‐, and IFNγ‐induced signaling via STAT1/STAT3 pathways, likely through excessive SOCS activation.
Glutamate Export at the Choroid Plexus in Health, Thiamin Deficiency, and Ethanol Intoxication: Review and Hypothesis
Authors: Nixon Peter F.
Published: July 2008

Introduction: The earliest observed effect in the pathogenesis of experimental Wernicke’s encephalopathy and of ethanol intoxication in rats is impairment of the blood cerebrospinal fluid (CSF) barrier at the choroid plexus (CP). For an explanation, these observations direct attention to the role of the CP in maintaining glutamate homeostasis in the CSF.

Methods: Characteristics of the CP epithelium (CPE) are reviewed, focusing on its role in removal of glutamate from the CSF and its potential for impairment by ethanol oxidation or by thiamin‐deficient glucose oxidation.

Results: The export of glutamate from CSF to blood at the CP is energy dependent, saturable, and stereospecific. However, the incapacity of the CP to convert glutamate to other metabolites makes it vulnerable to glutamate accumulation should α‐ketoglutarate dehydrogenase activity be decreased. Elsewhere ethanol metabolism and thiamin‐deficiency independently decrease the activity of this mitochondrial enzyme. We argue that they have the same effect within the mitochondria‐rich CPE, thereby decreasing energy production necessary for export of glutamate from CSF to blood; diverting its energy metabolism to further glutamate production; and impairing its blood CSF barrier function. This impairment appears to be mediated by glutamate and is attenuated by MK801 but whether it involves one of the CPE glutamate receptors is yet uncertain. This impairment exposes the CSF and hence the paraventricular brain extracellular fluid to neuroactive substances from the blood, including further glutamate, explaining the paraventricular location of neuropathology in Wernicke’s encephalopathy. Other organs normally protected from blood by a barrier are affected also by ethanol abuse and by thiamin deficiency, namely the eye, peripheral nerves, and the testis. Much less is known regarding the function of these barriers.

Conclusions: Impairment of the CP by ethanol intoxication and by thiamin‐deficient carbohydrate metabolism has a common, rational explanation that can guide future research.