bluuebunny/crossref_metadata_2025 huggingface dataset:
Tilted disc syndrome may mimic false visual field deterioration
Authors: Vuori Marja‐Liisa , Mäntyjärvi Maija
Published: August 2008

Purpose:  Tilted disc syndrome is a congenital anomaly of the eye characterized by mostly upper temporal visual field defects. The aim of the present study was to evaluate the effect of gradual myopic correction in the improvement of visual field defects associated with tilted disc syndrome.

Methods:  The visual field was examined in 38 eyes of 24 patients using standard Goldmann perimetry. The isoptres IV‐4e, I‐4e, I‐3e and I‐2e were plotted. The defective isoptres were tested again with gradually increasing myopic correction until no further change was noted.

Results:  The most common type of defect was a relative upper temporal defect (19 eyes). Temporal relative defects were found in five eyes, upper altitudinal field defects in six eyes, an enlarged blind spot in four eyes, and an inferior field defect in one eye. The visual field defect partly or totally disappeared with increased myopic correction in 18 (50%) eyes. The mean improvement was 17.0 ± 6.2 degrees and the mean additional myopic correction was 3.1 ± 1.5 D.

Conclusions:  Even a small change in near correction during visual field examination may imply worsened or improved visual field defects in tilted disc syndrome. To prevent a false interpretation of field deterioration in a patient with tilted disc syndrome and glaucoma, visual field assessment should include examination with the myopic correction that provides the maximal improvement of the defective visual field.
The Pyhäjärvi Cataract Study. I. Study design, baseline characteristics and the demand for cataract surgery
Authors: Falck Aura , Kuoppala Jaana , Winblad Ilkka , Tuulonen Anja
Published: August 2008

Purpose:  The Pyhäjärvi Cataract Study aims to study demand for cataract surgery in the population of a rural town in Finland.

Methods:  A random, population‐based sample of 881 persons aged ≥ 60 years were interviewed by telephone to obtain a Visual Function‐14 (VF‐14) score. A total of 294 persons were invited for an ophthalmic examination based on three categories of VF‐14 score. Of these, 230 (78%) responded, 10 of whom were excluded as a result of prior bilateral surgery. The New Zealand Priority Criteria (NZPC) and the 15‐Dimension Quality of Life (15‐D) instruments were administered. In addition, another group of 96 patients waiting for cataract surgery were examined and scored using the VF‐14, NZPC and 15‐D instruments. A modified Lens Opacities Classification System (LOCS) III classification was used for grading the cataract.

Results:  Only one (0.5%) of the 220 examined subjects was referred for cataract surgery. Many patients with relatively good visual acuity (VA), including six people with a 100‐point VF‐14 score suggesting no visual symptoms, were waiting for surgery. Demographic factors were not associated with access to cataract surgery. The patients examined from the waiting list for cataract surgery had more cataractous changes in the lens(es), poorer VA, were older, and scored higher on the NZPC instrument than the population sample examined.

Conclusions:  Practically no hidden demand for cataract surgery was found in the study population as defined by the national criteria for cataract surgery in Finland. This reflects the fact that the current Finnish health care system appears to recognize and treat cataract patients very well, even in rural areas. Although VA tests may not be sufficient for evaluating need for cataract surgery, the role of questionnaires is not clear either.
Innovations in non‐surgical periodontal therapy: Consensus Report of the Sixth European Workshop on Periodontology
Authors: Sanz M. , Teughels W. ,   on behalf of group A of the European Workshop on Periodontology
Published: August 2008

Introduction: The remit of this working group was to update the existing knowledge base in non‐surgical periodontal therapy. The published systematic reviews from the fourth EAP Workshop formed the starting point for this update and in addition specific innovations not covered in previous workshops were included.

Material and Methods: The literature was systematically searched and critically reviewed. Five manuscripts were produced in five specific topics identified as areas where innovative approaches have been developed in non‐surgical periodontal therapy and which were deemed to be strategically important for patient care and clinical practice.

Results: The results and conclusions of the review process are presented in the following papers, together with the group consensus statements, clinical implications and directions for future research: A systematic review of the effects of full mouth debridement with and without antiseptics in patients with chronic periodontitis. Advances in Power Driven Instrumentation. Laser application in non‐surgical periodontal therapy – a systematic review. Antimicrobial therapy in periodontitis: the use of systemic antimicrobials against the subgingival biofilm. The cost‐effectiveness of supportive periodontal‐care for patients with chronic periodontitis.
A systematic review of the effects of full‐mouth debridement with and without antiseptics in patients with chronic periodontitis
Authors: Lang Niklaus P. , Tan Wah Ching , Krähenmann Michael A. , Zwahlen Marcel
Published: August 2008

Objectives: To assess the clinical and microbiological effects of full‐mouth debridement with (FMD) and without the use of antiseptics [full‐mouth scaling and root planing (FMSRP)] in comparison with conventional staged debridement (CSD) in patients with chronic periodontitis after at least 6 months.

Material and Methods: The search in MEDLINE (PubMed), covering a period of 1975 to October 2007, and hand searching yielded 207 titles. Forty‐two abstracts and 17 full‐text articles were screened for inclusion.

Results: Twelve articles allowed a direct comparison of FMD with CSD, FMSRP with CSD and FMD with FMSRP. Probing pocket depth reductions were significantly greater (0.2 mm) with FMD and FMSRP compared with CSD. Moreover, a modest reduction in BOP (9%) favoured FMD. Likewise, clinical attachment levels were improved by 0.2–0.4 mm in favour of FMD and FMSRP, respectively. In all comparisons, single‐rooted teeth and deep pockets benefitted slightly from FMD and FMSRP. Limited differences in the changes of the subgingival microbiota were noted between the treatment modalities.

Conclusions: Despite the significant differences of modest magnitude, FMD or FMSRP do not provide clinically relevant advantages over CSD. Hence, all three treatment modalities may be recommended for debridement in the initial treatment of patients with chronic periodontitis.
Antimicrobial therapy in periodontitis: the use of systemic antimicrobials against the subgingival biofilm
Authors: Herrera David , Alonso Bettina , León Rubén , Roldán Silvia , Sanz Mariano
Published: August 2008

Objectives: The aim was to answer three relevant questions: can systemic antimicrobials be efficacious if the biofilm is not disrupted? Can the type of debridement of the subgingival biofilm impact upon the clinical outcomes of the adjunctive antimicrobial therapy? Is the efficacy of the adjunctive systemic antimicrobial therapy dependent on the quality of the debridement of the subgingival biofilm and the sequence debridement–antibiotic usage?

Material and Methods: Relevant papers were searched, critically analysed and their data were extracted.

Results: For the first question, studies assessing susceptibility of bacteria in biofilms, and clinical studies evaluating systemic antimicrobials as monotherapy, were reviewed. For the second question, clinical studies comparing systemic antimicrobials as adjuncts to non‐surgical debridement or to periodontal surgery and clinical trials using systemic antibiotics with periodontal surgery were evaluated. For the third question, a previous systematic review was updated.

Conclusion: If systemic antimicrobials are indicated in periodontal therapy, they should be adjunctive to mechanical debridement. There is not enough evidence to support their use with periodontal surgery. Indirect evidence suggests that antibiotic intake should start on the day of debridement completion, debridement should be completed within a short time (preferably <1 week) and with an adequate quality, to optimize the results.
Biological mediators and periodontal regeneration: a review of enamel matrix proteins at the cellular and molecular levels
Authors: Bosshardt Dieter D.
Published: August 2008

Background: Despite a large body of clinical and histological data demonstrating beneficial effects of enamel matrix proteins (EMPs) for regenerative periodontal therapy, it is less clear how the available biological data can explain the mechanisms underlying the supportive effects of EMPs.

Objective: To analyse all available biological data of EMPs at the cellular and molecular levels that are relevant in the context of periodontal wound healing and tissue formation.

Methods: A stringent systematic approach was applied using the key words “enamel matrix proteins” OR “enamel matrix derivative” OR “emdogain” OR “amelogenin”. The literature search was performed separately for epithelial cells, gingival fibroblasts, periodontal ligament cells, cementoblasts, osteogenic/chondrogenic/bone marrow cells, wound healing, and bacteria.

Results: A total of 103 papers met the inclusion criteria. EMPs affect many different cell types. Overall, the available data show that EMPs have effects on: (1) cell attachment, spreading, and chemotaxis; (2) cell proliferation and survival; (3) expression of transcription factors; (4) expression of growth factors, cytokines, extracellular matrix constituents, and other macromolecules; and (5) expression of molecules involved in the regulation of bone remodelling.

Conclusion: All together, the data analysis provides strong evidence for EMPs to support wound healing and new periodontal tissue formation.
Clinical outcomes with bioactive agents alone or in combination with grafting or guided tissue regeneration
Authors: Trombelli Leonardo , Farina Roberto
Published: August 2008

Aim: The purpose of the present review was to determine the clinical effect of the use of bioactive agents (BAs) for the treatment of intra‐osseous and furcation defects.

Material and Methods: The effectiveness of the BAs was evaluated when used in addition to open flap debridement either alone or in association with grafts and/or guided tissue regeneration (GTR). Among the included agents, recombinant human platelet‐derived growth factor‐BB (rhPDGF‐BB), platelet‐rich plasma (PRP), commercially available enamel matrix derivative (cEMD) and peptide P‐15 (P‐15) have been clinically tested for treating periodontal defects.

Results and Conclusions: The results of the present review indicate that: (1) cEMD either alone or in combination with grafts can be effectively used to treat intra‐osseous defects and the clinical results appear to be stable long term; (2) the additional use of a graft seems to enhance the clinical outcome of cEMD; (3) the combined use of rhPDGF‐BB and P‐15 with a graft biomaterial has shown beneficial effects in intra‐osseous defects; (4) contrasting results were reported for PRP and graft combinations; and (5) limited evidence supports the use of BAs either alone or in association with graft/GTR for the treatment of furcation defects.
Soft tissue management at implant sites
Authors: Cairo Francesco , Pagliaro Umberto , Nieri Michele
Published: August 2008

Background: Dental implants are widely used to replace lost teeth. It was suggested that surgical manipulation/augmentation of peri‐implant soft tissue may be beneficial to increase the width/thickness of keratinized tissue (KT) and to enhance aesthetic outcomes of implant therapy. The aim of this paper was to provide a narrative review of the literature concerning soft tissue management at implant sites.

Material and Methods: Clinical studies were identified with both medline and hand searches. Three topics were considered in this review: (i) the significance of KT at implant sites, (ii) the surgical techniques to increase KT and (iii) soft tissue stability around implants.

Results: Several papers concerning soft tissue management at implant sites were identified, mainly expert opinions, case reports and case series. In addition, a systematic review was selected. Generally, the level of evidence was weak. So far, literature analysis showed that (i) the width of KT did not influence the survival rate of dental implants; (ii) there is no evidence to recommend a specific technique to preserve/augment KT; and (iii) factors including bone level, KT and implant features have not been shown to be associated with future mucosal recession around dental implants.

Conclusion: Although scientific evidence in most part is lacking, soft tissue augmentation at implant sites may need to be considered in some clinical situations.
Assessment of the potential of growth factors for localized alveolar ridge augmentation: a systematic review
Authors: Jung Ronald E. , Thoma Daniel S. , Hammerle Christoph H. F.
Published: August 2008

Objective: To systematically assess the literature regarding the clinical, histological, and radiographic outcome of bone morphogenetic proteins (BMP‐2, BMP‐7), growth/differentiation factor‐5 (GDF‐5), platelet‐derived growth factor (PDGF), and parathyroid hormone (PTH) for localized alveolar ridge augmentation.

Material and Methods: Five separate Medline searches were performed in duplicate for human and animal studies, respectively. The primary outcome of the included studies was bone regeneration of localized alveolar ridge defects or craniofacial defects.

Results: In six human studies, BMP‐2 affected local bone augmentation with increasing volume for higher doses. A majority (43 of 45) of animal studies using BMP‐2 showed a positive effect in favour of the growth factor (GF). In six of eight studies, a positive effect was associated with the use of BMP‐7. Only one animal study was included for GDF‐5 revealing statistically significantly higher bone volume. Regarding PDGF, statistically significantly higher bone volume was observed in five of 10 included studies. Four animal studies using PTH revealed statistically significantly more bone regeneration compared with controls.

Conclusions: Differing levels and quantity of evidence were noted to be available for the GFs evaluated, revealing that BMP‐2, BMP‐7, GDF‐5, PDGF, and PTH may stimulate local bone augmentation to various degrees. Human data for the potential of rhBMP‐2 are supportive.
A systematic review of the success of sinus floor elevation and survival of implants inserted in combination with sinus floor elevation
Authors: Pjetursson Bjarni E. , Tan Wah Ching , Zwahlen Marcel , Lang Niklaus P.
Published: August 2008

Objectives: The objectives of this systematic review were to assess the survival rate of grafts and implants placed with sinus floor elevation.

Material and Methods: An electronic search was conducted to identify studies on sinus floor elevation, with a mean follow‐up time of at least 1 year after functional loading.

Results: The search provided 839 titles. Full‐text analysis was performed for 175 articles resulting in 48 studies that met the inclusion criteria, reporting on 12,020 implants. Meta‐analysis indicated an estimated annual failure rate of 3.48% [95% confidence interval (CI): 2.48%–4.88%] translating into a 3‐year implant survival of 90.1% (95% CI: 86.4%–92.8%). However, when failure rates was analyzed on the subject level, the estimated annual failure was 6.04% (95% CI: 3.87%–9.43%) translating into 16.6% (95% CI: 10.9%–24.6%) of the subjects experiencing implant loss over 3 years.

Conclusion: The insertion of dental implants in combination with maxillary sinus floor elevation is a predictable treatment method showing high implant survival rates and low incidences of surgical complications.

The best results (98.3% implant survival after 3 years) were obtained using rough surface implants with membrane coverage of the lateral window.
Periodontal diseases and health: Consensus Report of the Sixth European Workshop on Periodontology
Authors: Kinane Denis , Bouchard Phillippe ,   on behalf of group E of the European Workshop on Periodontology
Published: August 2008

Introduction: The remit of this group was to update the knowledge base on periodontal diseases and health.

Material and Methods: The literature was systematically searched and critically reviewed in five specific topics.

Results: Prevalence of periodontitis: The data suggest a trend towards a lower prevalence of periodontitis in recent years.

Adverse pregnancy outcome: The findings indicate a likely association between periodontal disease and an increased risk of adverse pregnancy outcomes. There is no evidence that treating periodontal disease decreases the rate of adverse pregnancy outcomes.

Prevalence and distribution of periodontal pathogens: Genetic analysis of bacteria has demonstrated an unanticipated diversity within species. Carriage rates and particular subsets of these species vary between ethnic groups. Few of these differences can be related to differences in disease prevalence.

Diabetes mellitus: Evidence on the association supports the concept of increased severity but not extent of periodontitis in subjects with poorly controlled diabetes. It is inconclusive that periodontal treatment results in improved metabolic control.

Cardiovascular diseases: Evidence suggests that having periodontitis contributes to the total infectious and inflammation burden and may contribute to cardiovascular events and stroke in susceptible subjects. The impact of periodontal therapy must be further investigated.
A critical assessment of adverse pregnancy outcome and periodontal disease
Authors: Wimmer Gernot , Pihlstrom Bruce L.
Published: August 2008

Background: Pre‐term birth is a major cause of infant mortality and morbidity that has considerable societal, medical, and economic costs. The rate of pre‐term birth appears to be increasing world‐wide and efforts to prevent or reduce its prevalence have been largely unsuccessful.

Aim: To review the literature for studies investigating periodontal disease as a possible risk factor for pre‐term birth and adverse pregnancy outcomes.

Main Findings and Conclusion: Variability among studies in definitions of periodontal disease and adverse pregnancy outcomes as well as widespread inadequate control for confounding factors and possible effect modification make it difficult to base meaningful conclusions on published data. However, while there are indications of an association between periodontal disease and increased risk of adverse pregnancy outcome in some populations, there is no conclusive evidence that treating periodontal disease improves birth outcome. Based on a critical qualitative review, available evidence from clinical trials indicates that, although non‐surgical mechanical periodontal treatment in the second trimester of pregnancy is safe and effective in reducing signs of maternal periodontal disease, it does not reduce the rate of pre‐term birth. Clinical trials currently underway will further clarify the potential role of periodontal therapy in preventing adverse birth outcomes. Regardless of the outcomes of these trials, it is recommended that large, prospective cohort studies be conducted to assess risk for adverse pregnancy outcome in populations with periodontal disease. It is critical that periodontal exposure and adverse birth outcomes be clearly defined and the many potential confounding factors and possible effect modifiers for adverse pregnancy outcome be controlled in these studies. If periodontal disease is associated with higher risk of adverse pregnancy outcome in these specific populations, large multicenter randomized‐controlled trials will be needed to determine if prevention or treatment of periodontal disease, perhaps combined with other interventions, has an effect on adverse pregnancy outcome in these women.
Reproductive Inequality in Sub‐Saharan Africa: Differentials versus Concentration
Authors: Giroux Sarah C. , Eloundou‐Enyegue Parfait M. , Lichter Daniel T.
Published: August 2008

Within developing countries, our understanding of reproductive inequality—how fertility is distributed within a population—has been shaped largely by studies of fertility differentials, a practical but partial‐information measure. In this study, we examine whether exclusive reliance on differentials biases this understanding, Findings based on recent data from sub‐Saharan Africa show bias. We find that historical and especially cross‐country comparisons can yield substantially different conclusions about the magnitude and even the direction of inequality patterns and trends, depending on whether differentials or fuller‐information measures are used. For instance, the fertility differentials associated with education have remained relatively stable as national fertility has fallen, but inequality (as calculated by a fuller measure) has increased. Such results underscore the value of complementing existing studies of fertility differentials with analyses based on fuller‐information measures. The analyses also show how change in differential fertility behavior and in the educational composition of national populations has shaped recent variations in reproductive inequality in the region.
Knowledge and Opinions of Emergency Contraceptive Pills Among Female Factory Workers in Tijuana, Mexico
Authors: García Sandra G. , Becker Davida , De Castro Marcela Martínez , Paz Francisco , Olavarrieta Claudia Díaz , Acevedo‐García Dolores
Published: August 2008

Workers in Mexico's maquiladoras (assembly plants) are mainly young, single women, many of whom could benefit from emergency contraceptive pills (ECPs). Because ECPs are readily available in Mexico, women who know about the therapy can obtain it easily. Do maquiladora workers know about the method? Could worksite programs help increase awareness? To investigate these questions, we conducted a five‐month intervention during which workers in three maquiladoras along the Mexico‐United States border could attend educational talks on ECPs, receive pamphlets, and obtain kits containing EC supplies. Among the workers exposed to our intervention, knowledge of ECPs increased. Reported ECP use also increased. Although our intervention apparently increased workers’ knowledge and use, the factory proved to be a difficult intervention setting. Problems we experienced included a factory closure and management/staff opposition to certain project elements. Future studies should continue to investigate work‐site interventions and other strategies to reach workers.
Is there a standard measuring rod in the Universe?
Authors: Jackson J. C.
Published: August 2008

The Caltech-Jodrell Bank very long baseline interferometry (VLBI) Surveys give detailed 5 GHz VLBI images of several hundred milliarcsecond (mas) radio sources, and the full width at half-maximum angular sizes of the corresponding compact cores. Using the latter, I have constructed an angular-diameter/redshift diagram comprising 271 objects, which shows clearly the expected features of such a diagram, without redshift binning. Cosmological parameters are derived which are compatible with existing consensus values, particularly when the VLBI data are combined with recent Baryon Acoustic Oscillations observations; the figures are presented as indications of what might be expected of larger samples of similar data. The importance of beaming and relativistic motion towards the observer is stressed; a model of the latter indicates that the emitting material is close to the observer's line of sight and moving with a velocity which brings it close to the observer's rest frame. With respect to linear size, these objects compare reasonably well in variance with the absolute luminosity of type Ia supernovae; the efficacy of the latter is improved by the brighter-slower and brighter-bluer correlations, and by the inverse-square law.
Intelligent Space Tube Optimization for Speeding Ground Water Remedial Design
Authors: Kalwij Ineke M. , Peralta Richard C.
Published: August 2008

An innovative Intelligent Space Tube Optimization (ISTO) two‐stage approach facilitates solving complex nonlinear flow and contaminant transport management problems. It reduces computational effort of designing optimal ground water remediation systems and strategies for an assumed set of wells. ISTO’s stage 1 defines an adaptive mobile space tube that lengthens toward the optimal solution. The space tube has overlapping multidimensional subspaces. Stage 1 generates several strategies within the space tube, trains neural surrogate simulators (NSS) using the limited space tube data, and optimizes using an advanced genetic algorithm (AGA) with NSS. Stage 1 speeds evaluating assumed well locations and combinations. For a large complex plume of solvents and explosives, ISTO stage 1 reaches within 10% of the optimal solution 25% faster than an efficient AGA coupled with comprehensive tabu search (AGCT) does by itself. ISTO input parameters include space tube radius and number of strategies used to train NSS per cycle. Larger radii can speed convergence to optimality for optimizations that achieve it but might increase the number of optimizations reaching it. ISTO stage 2 automatically refines the NSS‐AGA stage 1 optimal strategy using heuristic optimization (we used AGCT), without using NSS surrogates. Stage 2 explores the entire solution space. ISTO is applicable for many heuristic optimization settings in which the numerical simulator is computationally intensive, and one would like to reduce that burden.
Ground Water Sustainability: Methodology and Application to the North China Plain
Authors: Liu Jie , Zheng Chunmiao , Zheng Li , Lei Yuping
Published: August 2008

This article analyzes part of a ground water flow system in the North China Plain (NCP) subject to severe overexploitation and rapid depletion. A transient ground water flow model was constructed and calibrated to quantify the changes in the flow system since the predevelopment 1950s. The flow model was then used in conjunction with an optimization code to determine optimal pumping schemes that improve ground water management practices. Finally, two management scenarios, namely, urbanization and the South‐to‐North Water Transfer Project, were evaluated for their potential impacts on the ground water resources in the study area. Although this study focuses on the NCP, it illustrates a general modeling framework for analyzing the sustainability, or the lack thereof, of ground water flow systems driven by similar hydrogeologic and economic conditions. The numerical simulation is capable of quantifying the various components of the overall flow budget and evaluating the impacts of different management scenarios. The optimization modeling allows the determination of the maximum “sustainable pumping” that satisfies a series of prescribed constraints. It can also be used to minimize the economic costs associated with ground water development and management. Furthermore, since the NCP is one of the most water scarce and economically active regions in the world, the conclusions and insights from this study are of general interest and international significance.
Asymmetric Abstraction and Allocation: The Israeli‐Palestinian Water Pumping Record
Authors: Zeitoun Mark , Messerschmid Clemens , Attili Shaddad
Published: August 2008

The increased attention given to international transboundary aquifers may be nowhere more pressing than on the western bank of the Jordan River. Hydropolitical analysis of six decades of Israeli and Palestinian pumping records reveals how ground water abstraction rates are as asymmetrical as are water allocations. The particular hydrogeology of the region, notably the variability in depth to ground water, variations in ground water quality, and the vulnerability of the aquifer, also affect the outcome. The records confirm previously drawn conclusions of the influence of the agricultural lobby in maintaining a supply‐side water management paradigm. Comparison of water consumption rates divulges that water consumed by all sectors of the farming‐based Palestinian economy is less than half of Israeli domestic consumption. The overwhelming majority of “reserve” flows from wet years are sold at subsidized rates to the Israeli agricultural sector, while very minor amounts are sold at normal rates to the Palestinian side for drinking water. An apparent coevolution of water resource variability and politics serves to explain increased Israeli pumping prior to negotiations in the early 1990s. The abstraction record from the Western Aquifer Basin discloses that the effective limit set by the terms of the 1995 Oslo II Agreement is regularly violated by the Israeli side, thereby putting the aquifer at risk. The picture that emerges is one of a transboundary water regime that is much more exploitative than cooperative and that risks spoiling the resource as it poisons international relations.
The role of marine aquaculture in meeting the future demand for animal protein
Authors: Langan Richard
Published: August 2008

Farm‐raised seafood is expected to play a major role in meeting the future demand for animal protein; however, the growth of marine aquaculture as currently practiced is constrained by space, economics and environmental concerns. For aquaculture to continue to expand, the potential of farming offshore ocean waters must be explored. Over the past decade, there has been worldwide interest in exploring the potential for offshore production, and the USA has emerged as one of the leaders in developing and demonstrating technologies for farming in the open ocean culture. Offshore research and development projects in New Hampshire, Hawaii and Puerto Rico have led to small‐scale commercial production, demonstrating that open ocean culture is indeed feasible and has great potential for future expansion. Despite the evidence that offshore farming is possible, a number of technical, economic and political challenges must be addressed before large‐scale production can be realized.
Environmental sources of microbial contaminants in shellfish and their public health significance
Authors: Jones Stephen H.
Published: August 2008

Shellfish‐harvesting waters are subject to a variety of pollution sources. Different sources pose different public threats; human sources are of more concern than nonhuman, and domestic animals are of more concern than wild animals. The type of source is also important because management strategies for eliminating sources may not be available for some wild animal sources. Water samples were collected from shellfish waters at two sites in coastal New Hampshire (NH) and on Martha's Vineyard, Massachusetts, and were analyzed for Escherichia coli. E. coli isolates were ribotyped, and their ribopatterns were statistically compared to databases containing patterns from known source species. Each study area was significantly impacted by different types of source species including humans and pets at one NH site, wild animals at the other NH site, and birds at Martha's Vineyard. Strategies are available for managing these sources to improve water quality and reduce the public health threat.
Balancing the risks and benefits of fish for sensitive populations
Authors: Santerre Charles R.
Published: August 2008

In recent years, a number of concerns have been raised about the safety of fish. Environmental pollutants that accumulate in selected seafood products have caused some to regard fish as potentially dangerous for fetuses, nursing infants and young children. Yet, nutritionists contend that seafood can provide benefits which far outweigh the risks. In this review, we will briefly discuss the health benefits of eating fish, and compare these to the risks from two environmental pollutants (mercury and polychlorinated biphenyls or PCBs). In addition, we will provide advice for sensitive populations (women who will become pregnant, pregnant or nursing women, and children younger than 6 years of age), which can help them to make informed decisions involving fish consumption. The ultimate goal is to maximize the benefits and minimize the risks from eating seafood.
Understanding the factors related to the consumers' choices of oysters in Australia: an empirical study
Authors: Kow Felicia , Yu Liu , FitzGerald Des , Grewal Devinder
Published: August 2008

Oysters, one of the most popular shellfish, constitute an important food commodity in Australia. With the rapid growth of production, Australian oyster suppliers have realized the need for a better understanding of oyster consumption patterns to maximize economic returns. This study examines oyster consumer demographics and attitudes towards oysters, which in turn identify antecedent variables influencing consumer choice of oysters. Relevant antecedent variables such as quality, safety, labelling and preferred values were identified by factor analysis. A logistic regression analysis predicts consumer choice of oysters using those antecedent variables and the demographic factors. We recommend factors to be considered in the marketing of oysters.
The influence of foreign direct investment on contracting confidence in developing countries
Authors: Ahlquist John S. , Prakash Aseem
Published: August 2008

This paper examines whether foreign direct investment (FDI) influences confidence in commercial contracts in developing countries. While the research on how host countries’ policy environments encourage FDI inflows has flourished, scholars have paid less attention to how the policy environment and local actors’ beliefs might, in turn, be affected by FDI. This is surprising because multinational enterprises are well‐recognized political and economic actors across the world. We expect that their increasing economic salience will influence the policy environments in which they function. By employing an innovative measure of property rights protection – contract‐intensive money – we examine how foreign direct investment influences host countries’ contract‐intensive money ratio in a large panel time series of both developed and developing countries from 1980 to 2002. Our analysis suggests that higher levels of FDI inflows are associated with greater confidence in commercial contracts and, by extension, the protection of property rights in developing countries.
Regulation through titling laws: A case study of occupational regulation
Authors: Carpenter Dick M.
Published: August 2008

This case study examines a form of occupational regulation infrequently examined in academic literature – titling laws. These laws regulate who may legally use a phrase, or title, to describe their work to the public. Focusing on the interior design industry, this article demonstrates how industry leaders use titling laws as the first step in a push for full occupational licensure. In so doing, they allege a need for regulation out of concern for public health and safety, but as data in this case study indicate, there appears to be no threat to public health and safety from unregulated interior designers. Instead, designers advocate for increased regulation of their own industry, through the evolution of titling laws to full licensure, due to the benefits it affords them.
ACTA‐EVER lecture 2007 The retinal pigment epithelium: friend or foe?
Authors: La Cour Morten
Published: August 2008

The retinal pigment epithelium (RPE) plays an important role in the physiology and pathophysiology of the vertebrate retina. The RPE absorbs fluid from the retinal extracellular space, via a proton–lactate–water co‐transport mechanism located in the apical membrane of the epithelium. This mechanism can account for the apparent capability of the RPE to absorb water against an osmotic gradient. RPE cells participate in retinal wound healing. We have created a porcine model of experimental choroidal neovascularization (CNV). In this model, the CNV eventually becomes enveloped by seemingly proliferating RPE cells. By means of 5‐bromo‐2‐deoxyuridine (BrdU) labelling, we studied the proliferation of RPE cells in the porcine eye after experimental posterior pole injury. Surprisingly, we found that only the peripheral RPE cells incorporated the BrdU label, indicating that central injury elicits peripheral RPE proliferation. This might suggest the existence of a peripheral pool of RPE stem cells. RPE cell proliferation plays a role in the pathological wound healing known as proliferative vitreoretinopathy. Antiproliferative agents have been tried to treat this condition but with little success so far. We report on a drug delivery system under development where a prodrug of the antimetabolite 5‐fluoro‐uracil (5‐FU) is suspended in the silicone oil used as a surgical device in the treatment of proliferative vitreoretinopathy (PVR). The theoretical advantage of this approach is that it allows for long contact times between therapeutic, and non‐toxic, concentrations of 5‐FU and the RPE.
Real-Time PCR Detection of
gyrA
and
parC
Mutations in
Streptococcus pneumoniae
Authors: Page S. , Vernel-Pauillac F. , O'Connor O. , Bremont S. , Charavay F. , Courvalin P. , Goarant C. , Le Hello S.
Published: August 2008

Fluoroquinolone resistance in
Streptococcus pneumoniae
mainly involves stepwise mutations predominantly in the
parC
and
gyrA
genes. We have developed a single-run real-time PCR assay for detection of the four most common mutations in the quinolone resistance-determining regions of these genes. This assay provides a useful tool for both clinical and epidemiological use.
Effect of Electrical Current on the Activities of Antimicrobial Agents against
Pseudomonas aeruginosa
,
Staphylococcus aureus
, and
Staphylococcus epidermidis
Biofilms
Authors: del Pozo Jose L. , Rouse Mark S. , Mandrekar Jayawant N. , Sampedro Marta Fernandez , Steckelberg James M. , Patel Robin
Published: August 2008

Bacterial biofilms are resistant to conventional antimicrobial agents. Prior in vitro studies have shown that electrical current (EC) enhances the activities of aminoglycosides, quinolones, and oxytetracycline against
Pseudomonas aeruginosa
,
Klebsiella pneumoniae
,
Staphylococcus epidermidis
,
Escherichia coli
, and
Streptococcus gordonii
. This phenomenon, known as the bioelectric effect, has been only partially defined. The purpose of this work was to study the in vitro bioelectric effect on the activities of 11 antimicrobial agents representing a variety of different classes against
P. aeruginosa
, methicillin-resistant
Staphylococcus aureus
(MRSA), and
S. epidermidis
. An eight-channel current generator/controller and eight chambers delivering a continuous flow of fresh medium with or without antimicrobial agents and/or EC to biofilm-coated coupons were used. No significant decreases in the numbers of log
10
CFU/cm
2
were seen after exposure to antimicrobial agents alone, with the exception of a 4.57-log-unit reduction for
S. epidermidis
and trimethoprim-sulfamethoxazole. We detected a statistically significant bioelectric effect when vancomycin plus 2,000 microamperes EC were used against MRSA biofilms (
P
= 0.04) and when daptomycin and erythromycin were used in combination with 200 or 2,000 microamperes EC against
S. epidermidis
biofilms (
P
= 0.02 and 0.0004, respectively). The results of these experiments indicate that the enhancement of the activity of antimicrobial agents against biofilm organisms by EC is not a generalizable phenomenon across microorganisms and antimicrobial agents.
Characterization of TolC Efflux Pump Proteins from
Pasteurella multocida
Authors: Hatfaludi Tamas , Al-Hasani Keith , Dunstone Michelle , Boyce John , Adler Ben
Published: August 2008

Two TolC homologs, PM0527 and PM1980, were identified for
Pasteurella multocida
. A pm0527 mutant displayed increased susceptibility to a range of chemicals, including rifampin (512-fold) and acridine orange (128-fold). A pm1980 mutant showed increased susceptibility to rifampin, ceftazidime, and vancomycin.
Proposed MIC and Disk Diffusion Microbiological Cutoffs and Spectrum of Activity of Retapamulin, a Novel Topical Antimicrobial Agent
Authors: Traczewski Maria M. , Brown Steven D.
Published: August 2008

Retapamulin, the first pleuromutilin antimicrobial agent approved for the topical treatment of skin infections in humans, was tested against 987 clinical isolates representing 30 species and/or resistance groups. MICs were determined along with disk diffusion zone diameters using a 2-μg disk. Population distribution and MIC versus disk zone diameter scattergrams were analyzed to determine microbiological MIC cutoff values and inhibition zone correlates. Minimum bactericidal concentrations were performed on a smaller subset of key species. The retapamulin MIC
90
against 234
Staphylococcus aureus
isolates and 110 coagulase-negative staphylococci was 0.12 μg/ml. Retapamulin MIC
90
s ranged from 0.03 to 0.06 μg/ml against beta-hemolytic streptococci including 102
Streptococcus pyogenes
, 103
Streptococcus agalactiae
, 59 group C
Streptococcus
, and 71 group G
Streptococcus
isolates. The MIC
90
against 55 viridans group streptococci was 0.25 μg/ml. Retapamulin had very little activity against 151 gram-negative bacilli and most of the
Enterococcus
species tested. Based on the data from this study, for staphylococci, MICs of ≤0.5, 1, and ≥2 μg/ml with corresponding disk diffusion values of ≥20 mm, 17 to 19 mm, and ≤16 mm can be proposed for susceptible, intermediate, and resistant microbiological cutoffs, respectively. For beta-hemolytic streptococci, a susceptible-only MIC of ≤0.25 μg/ml with a corresponding disk diffusion value of ≥15 mm can be proposed for susceptible-only microbiological cutoffs.
Plasmodium falciparum
Strains Harboring Dihydrofolate Reductase with the I164L Mutation Are Absent in Malawi and Zambia Even under Antifolate Drug Pressure
Authors: Ochong Edwin , Bell David J. , Johnson David J. , D'Alessandro Umberto , Mulenga Modest , Muangnoicharoen Sant , Van Geertruyden Jean-Pierre , Winstanley Peter A. , Bray Patrick G. , Ward Stephen A. , Owen Andrew
Published: August 2008

The
Plasmodium falciparum
dihydrofolate reductase (PfDHFR) enzyme is the target of pyrimethamine, a component of the antimalarial pyrimethamine-sulfadoxine. Resistance to this drug is associated primarily with mutations in the Pf
dhfr
gene. The I164L mutant allele is of particular interest, because strains possessing this mutation are highly resistant to pyrimethamine and to chlorproguanil, a component of chlorproguanil-dapsone. A recent study from Malawi reported this mutation at a prevalence of 4.7% in parasites from human immunodeficiency virus-positive pregnant women by using a real-time PCR method. These observations have huge implications for the use of pyrimethamine-sulfadoxine, chlorproguanil-dapsone, and future antifolate-artemisinin combinations in Africa. It was imperative that this finding be rigorously tested. We identified a number of critical limitations in the original genotyping strategy. Using a refined and validated real-time PCR strategy, we report here that this mutation was absent in 158 isolates from Malawi and 42 isolates from Zambia collected between 2003 and 2005.
In Vitro Activity of OPT-80 Tested against Clinical Isolates of Toxin-Producing
Clostridium difficile
Authors: Karlowsky James A. , Laing Nancy M. , Zhanel George G.
Published: August 2008

Agar dilution antimicrobial susceptibility testing (CLSI, M11-A7, 2007) performed for 208 toxin-producing clinical isolates of
Clostridium difficile
resulted in OPT-80 MICs ranging from 0.06 to 1 μg/ml, with 90% of the isolates inhibited by a concentration of 0.5 μg/ml. The in vitro activity of OPT-80 was independent of the susceptibilities of isolates to nine other antimicrobial agents.
Efficacy of Single-Dose Liposomal Amphotericin B or Micafungin Prophylaxis in a Neutropenic Murine Model of Invasive Pulmonary Aspergillosis
Authors: Lewis Russell E. , Albert Nathaniel D. , Kontoyiannis Dimitrios P.
Published: August 2008

In a neutropenic murine model of invasive pulmonary aspergillosis, prophylaxis with single doses of liposomal amphotericin B or micafungin at ≥5 mg/kg of body weight improved animal survival and suppressed the lung fungal burden for up to 7 days after infection, demonstrating the potential utility of infrequent dosing with these antifungals.
Pharmacodynamic Modeling of Aminoglycosides against
Pseudomonas aeruginosa
and
Acinetobacter baumannii
: Identifying Dosing Regimens To Suppress Resistance Development
Authors: Tam Vincent H. , Ledesma Kimberly R. , Vo Giao , Kabbara Samer , Lim Tze-Peng , Nikolaou Michael
Published: August 2008

To facilitate optimal dosing regimen design, we previously developed a mathematical model using time-kill study data to predict the responses of
Pseudomonas aeruginosa
to various pharmacokinetic profiles of meropenem and levofloxacin. In this study, we extended the model to predict the activities of gentamicin and amikacin exposures against
P. aeruginosa
and
Acinetobacter baumannii
, respectively. The input data were from a time-kill study with 10
7
CFU/ml of bacteria at baseline.
P. aeruginosa
ATCC 27853 was exposed to gentamicin (0 to 16× MIC; MIC = 2 mg/liter), and
A. baumannii
ATCC BAA 747 was exposed to amikacin (0 to 32× MIC; MIC = 4 mg/liter) for 24 h. Using the estimates of the best-fit model parameters, bacterial responses to various fluctuating aminoglycoside exposures (half-life, 2.5 h) over 72 h were predicted via computer simulation. The computer simulations were subsequently validated using an in vitro hollow-fiber infection model with similar aminoglycoside exposures. A significant initial reduction in the bacterial burden was predicted for all gentamicin exposures examined. However, regrowth over time due to resistance emergence was predicted for regimens with a maximum concentration of the drug (
C
max
)/MIC (dosing frequency) of 4 (every 8 h [q8h]), 12 (q24h), and 36 (q24h). Sustained suppression of bacterial populations was forecast with a
C
max
/MIC of 30 (q12h). Similarly, regrowth and suppression of
A. baumannii
were predicted and experimentally verified with a three-dimensional response surface. The mathematical model was reasonable in predicting extended bacterial responses to various aminoglycoside exposures qualitatively, based on limited input data. Our approach appears promising as a decision support tool for dosing regimen selection for antimicrobial agents.
Plasmid-Mediated Quinolone Resistance Determinants
qnrA
,
qnrB
, and
qnrS
among Clinical Isolates of
Enterobacteriaceae
in a Korean Hospital
Authors: Tamang Migma Dorji , Seol Sung Yong , Oh Jae-Young , Kang Hee Young , Lee Je Chul , Lee Yoo Chul , Cho Dong Taek , Kim Jungmin
Published: August 2008

Screening of 368 consecutive nonreplicate clinical isolates of
Enterobacteriaceae
resistant to nalidixic acid and at least one extended-spectrum β-lactam revealed the presence of
qnrA
,
qnrB
, and
qnrS
determinants, and identified novel
qnrB
variants, in
Citrobacter freundii
isolates. This study also revealed, for the first time, the linkage of
qnrB
,
armA
, and extended-spectrum and/or AmpC-type β-lactamase genes on large conjugative plasmids.