bluuebunny/crossref_metadata_2025 huggingface dataset:
Serial Noninvasive In Vivo Positron Emission Tomographic Tracking of Percutaneously Intramyocardially Injected Autologous Porcine Mesenchymal Stem Cells Modified for Transgene Reporter Gene Expression
Authors: Gyöngyösi Mariann , Blanco Jeronimo , Marian Teréz , Trón Lajos , Petneházy Örs , Petrasi Zsolt , Hemetsberger Rayyan , Rodriguez Julio , Font Gusztáv , Pavo Imre J. , Kertész István , Balkay László , Pavo Noemi , Posa Aniko , Emri Miklos , Galuska László , Kraitchman Dara L. , Wojta Johann , Huber Kurt , Glogar Dietmar
Published: August 2008

Background—

Porcine bone marrow-derived mesenchymal stem cells (MSCs) were stably transfected with a lentiviral vector for transgene expression of the trifusion protein renilla luciferase, red fluorescent protein and herpes simplex truncated thymidine kinase (LV-RL-RFP-tTK; positron emission tomography [PET] reporter gene) for in vivo noninvasive tracking of the intramyocardially delivered MSC fate.

Methods and Results—

A closed-chest, reperfused myocardial infarction was created in farm pigs. Sixteen days after myocardial infarction, LV-RL-RFP-tTK-MSCs were injected intramyocardially using electromechanical mapping guidance in the infarct border zone (n=7). PET-computed tomographic metabolic and perfusion imaging was performed after an intravenous injection of 10 mCi [18F]-FHBG and 13N-ammonia PET at 30�2 hours and 7 days after LV-RL-RFP-tTK-MSC treatment. Fusion imaging of the [18F]-FHBG PET-computed tomography with MRI was used to determine the myocardial location of the injected LV-RL-RFP-tTK-MSCs. Seven days after injections, [18F]-FHBG PET showed a decreased cardiac uptake with a mild increased pericardial and pleura uptake in the treated animals, which was confirmed by the measurement of luciferase activity. At 10 days, infarct size by MRI in the LV-RL-RFP-tTK-MSC-treated animals was smaller than controls (n=7) (23.3�1.5% versus 30.2�3.5%,
P
<0.005). The presence of the LV-RL-RFP-tTK-MSCs (5.8�1.1% of the injected cells) in the myocardium 10 days after intramyocardial delivery was confirmed histologically.

Conclusions—

Reporter gene imaging enables the tracking of the persistence of viable LV-RL-RFP-tTK-MSC in the peri-infarcted porcine myocardium at 10 days after delivery using clinical PET scanners.
Nitroglycerin-Induced S-nitrosylation and Desensitization of Soluble Guanylyl Cyclase Contribute to Nitrate Tolerance
Authors: Sayed Nazish , Kim David D. , Fioramonti Xavier , Iwahashi Toru , Durán Walter N. , Beuve Annie
Published: August 2008

Nitrates such as nitroglycerin (GTN) and nitric oxide donors such as S-nitrosothiols are clinically vasoactive through stimulation of soluble guanylyl cyclase (sGC), which produces the second messenger cGMP. Development of nitrate tolerance, after exposure to GTN for several hours, is a major drawback to a widely used cardiovascular therapy. We recently showed that exposure to nitric oxide and to S-nitrosothiols causes S-nitrosylation of sGC, which directly desensitizes sGC to stimulation by nitric oxide. We tested the hypothesis that desensitization of sGC by S-nitrosylation is a mechanism of nitrate tolerance. Our results established that vascular tolerance to nitrates can be recapitulated in vivo by S-nitrosylation through exposure to cell membrane-permeable S-nitrosothiols and that sGC is S-nitrosylated and desensitized in the tolerant, treated tissues. We next determined that (1) GTN treatment of primary aortic smooth muscle cells induces S-nitrosylation of sGC and its desensitization as a function of GTN concentration; (2) S-nitrosylation and desensitization are prevented by treatment with N-acetyl-cysteine, a precursor of glutathione, used clinically to prevent development of nitrate tolerance; and (3) S-nitrosylation and desensitization are reversed by cessation of GTN treatment. Finally, we demonstrated that in vivo development of nitrate tolerance and crosstolerance by 3-day chronic GTN treatment correlates with S-nitrosylation and desensitization of sGC in tolerant tissues. These results suggest that in vivo nitrate tolerance is mediated, in part, by desensitization of sGC through GTN-dependent S-nitrosylation.
Endothelium-Specific Interference With Peroxisome Proliferator Activated Receptor Gamma Causes Cerebral Vascular Dysfunction in Response to a High-Fat Diet
Authors: Beyer Andreas M. , de Lange Willem J. , Halabi Carmen M. , Modrick Mary L. , Keen Henry L. , Faraci Frank M. , Sigmund Curt D.
Published: August 2008

The ligand-activated transcription factor peroxisome proliferator activated receptor gamma (PPARγ) is expressed in vascular endothelium where it exerts anti-inflammatory and antioxidant effects. However, its role in regulating vascular function remains undefined. We examined endothelial function in transgenic mice expressing dominant-negative mutants of PPARγ under the control of an endothelial-specific promoter to test the hypothesis that endothelial PPARγ plays a protective role in the vasculature. Under baseline conditions, responses to the endothelium-dependent agonist acetylcholine were not affected in either aorta or the basilar artery in vitro. In response to feeding a high-fat diet for 12 weeks, acetylcholine produced dilation that was markedly impaired in the basilar artery of mice expressing dominant-negative mutants, but not in mice expressing wild-type PPARγ controlled by the same promoter. Unlike basilar artery, 12 weeks of a high-fat diet was not sufficient to cause endothelial dysfunction in the aorta of mice expressing dominant-negative PPARγ, although aortic dysfunction became evident after 25 weeks. The responses to acetylcholine in basilar artery were restored to normal after treatment with a scavenger of superoxide. Baseline blood pressure was only slightly elevated in the transgenic mice, but the pressor response to angiotensin II was augmented. Thus, interference with PPARγ in the endothelium produces endothelial dysfunction in the cerebral circulation through a mechanism involving oxidative stress. Consistent with its role as a fatty acid sensor, these findings provide genetic evidence that endothelial PPARγ plays a critical role in protecting blood vessels in response to a high-fat diet.
Corin Variant Associated With Hypertension and Cardiac Hypertrophy Exhibits Impaired Zymogen Activation and Natriuretic Peptide Processing Activity
Authors: Wang Wei , Liao Xudong , Fukuda Koichi , Knappe Sabine , Wu Faye , Dries Daniel L. , Qin Jun , Wu Qingyu
Published: August 2008

Corin is a cardiac serine protease that acts as the pro–atrial natriuretic peptide (ANP) convertase. Recently, 2 single-nucleotide polymorphisms (SNPs) (T555I and Q568P) in the human corin gene have been identified in genetic epidemiological studies. The minor I555/P568 allele, which is more common in African Americans, is associated with hypertension and cardiac hypertrophy. In this study, we examined the effect of T555I and Q568P amino acid substitutions on corin function. We found that corin frizzled-like domain 2, where T555I/Q568P substitutions occur, was required for efficient pro-ANP processing in functional assays. Mutant corin lacking this domain had 30±5% (
P
<0.01) activity compared to that of wild type. Similarly, corin variant T555I/Q568P had a reduced (38±7%,
P
<0.01) pro-ANP processing activity compared to that of wild type. The variant also exhibited a low activity (44±15%,
P
<0.05) in processing pro–brain natriuretic peptide (BNP). We next examined the biochemical basis for the loss of activity in T555I/Q568P variant and found that the zymogen activation of the corin variant was impaired significantly, as indicated by the absence of the activated protease domain fragment. This finding was confirmed in human embryonic kidney (HEK)293 cells and murine HL-1 cardiomyocytes. Thus, our results show that the corin gene SNPs associated with hypertension and cardiac hypertrophy impair corin zymogen activation and natriuretic peptide processing activity. Our data suggest that corin deficiency may be an important mechanism in hypertensive and heart diseases.
Tra2β As a Novel Mediator of Vascular Smooth Muscle Diversification
Authors: Shukla Supriya , Fisher Steven A.
Published: August 2008

Transformer splicing regulatory proteins determine the sexually dimorphic traits of
Drosophila
. The role of the vertebrate homologs of Tra-2 in phenotypic specification is undefined. We are using the alternative splicing of the MYPT1 E23 exon as a model for the study of smooth muscle diversification into fast and slow contractile phenotypes. Tra2β mRNA and protein is expressed at up to 10-fold higher levels in fast smooth muscle tissues such as the rat portal vein and small mesenteric artery, in which E23 is spliced, as compared to the slow smooth muscle tissues of the large arteries and veins, in which E23 is skipped. Tra2β is upregulated up to 10-fold concordant with the initiation of E23 splicing as the rat portal vein and avian gizzard implement the fast program of gene expression in the perinatal period. In disease models such as portal hypertension and mesenteric artery high/low flow, the portal vein and first order mesenteric artery dynamically downregulate Tra2β concordant with a shift to E23 skipping and the slow program of gene expression. Tra2β binds to a highly conserved sequence within E23 and transactivates its splicing in vitro and in vivo; this is abolished with mutation or deletion of this sequence. RNA interference–mediated knockdown of Tra2β markedly reduces E23 splicing. We propose that Tra2β has been conserved through evolution and redeployed for the specification of the fast smooth muscle phenotype and may serve as a novel nodal point for the investigation of this process in developmental and disease models.
International Subarachnoid Aneurysm Trial of Neurosurgical Clipping Versus Endovascular Coiling
Authors: Ryttlefors Mats , Enblad Per , Kerr Richard S.C. , Molyneux Andrew J.
Published: August 2008

Background and Purpose—

It is often thought that elderly patients in particular would benefit from endovascular aneurysm treatment. The aim of this analysis was therefore to compare the efficacy and safety of endovascular coiling (EVT) with neurosurgical clipping (NST) in the subgroup of elderly SAH patients in the International Subarachnoid Aneurysm Trial (ISAT).

Methods—

In the ISAT cohort 278 SAH patients, 65 years or older, were enrolled. The patients were randomly allocated EVT (n=138) or NST (n=140). The primary outcome was the proportion of patients with a modified Rankin scale score of 0 to 2 (independent survival) at 1 year after the SAH. The rates of procedural complications and adverse events were also recorded.

Results—

83 of 138 (60.1%) patients allocated EVT were independent compared to 78 of 140 (56.1%) allocated NST (N.S.). 36 of 50 (72.0%) patients with internal carotid and posterior communicating artery aneurysms allocated EVT were independent compared to 26 of 50 (52.0%) allocated NST (
P
<0.05). 10 of 22 (45.5%) patients with middle cerebral artery aneurysms allocated EVT were independent compared to 13 of 15 (86.7%) allocated NST (
P
<0.05). The epilepsy frequency was 0.7% in the EVT group compared to 12.9% in the NST group (
P
<0.001).

Conclusions—

In good grade elderly SAH patients with small anterior circulation aneurysms, EVT should probably be the favored treatment for ruptured internal carotid and posterior communicating artery aneurysms, whereas elderly patients with ruptured middle cerebral artery aneurysms appear to benefit from NST. EVT resulted in a lower epilepsy frequency than NST.
Continuous Measurement of Autoregulation by Spontaneous Fluctuations in Cerebral Perfusion Pressure
Authors: Brady Ken M. , Lee Jennifer K. , Kibler Kathleen K. , Easley R. Blaine , Koehler Raymond C. , Shaffner Donald H.
Published: August 2008

Background and Purpose—

Clinical application of continuous autoregulation monitoring would benefit from a comparison of curves generated by online monitoring with standard autoregulation curves in animal models. We characterized the accuracy of 3 continuous monitors of autoregulation in a piglet model of hypotension.

Methods—

Piglets 5 to10 days old with intracranial pressure (ICP) at naïve or elevated (20 mm Hg) levels had gradual arterial hypotension induced by a balloon catheter in the inferior vena cava. Elevated ICP was maintained by a continuous infusion of artificial cerebrospinal fluid. Three indices of autoregulation were simultaneously and continuously calculated. A moving, linear Pearson’s coefficient between spontaneous slow waves of cerebral perfusion pressure and slow waves of laser-Doppler flux or cortical oxygenation rendered the laser-Doppler index and cerebral-oximetry index, respectively. Similar correlation between slow waves of arterial blood pressure and ICP rendered the pressure-reactivity index. The lower limit of autoregulation was determined directly for each animal by plotting laser-Doppler cortical red blood cell flux as a function of cerebral perfusion pressure. Receiver-operator characteristics were determined for the 3 indices.

Results—

The areas under the receiver-operator characteristics curves for discriminating the individual lower limit of autoregulation at low and high ICP were 0.89 and 0.85 for the laser-Doppler index, 0.89 and 0.84 for the cerebral-oximetry index, and 0.79 and 0.79 for the pressure-reactivity index. The pressure-reactivity index performed equally well at low and high ICPs.

Conclusions—

Continuous monitoring of autoregulation by spontaneous slow waves of cerebral perfusion pressure can accurately detect loss of autoregulation due to hypotension in piglets by all 3 modalities.
Africa in Japanese Diplomatic Thought
Authors: Adem Seifudein
Published: August 2008

What is Africa’s place in Japanese diplomatic thought, and what are the driving forces of Japan’s African diplomacy in the new century? The need to maintain continuity in Japan’s post—Cold War Africa policy, leadership style, and priorities of Japan’s prime ministers, as well as broader considerations of the nation’s vital interests, are all relevant factors for understanding Japan’s diplomacy toward Africa in the new century.
Place Politics: Material Transformation and Community Identity at the National Civil Rights Museum
Authors: Armada Bernard J.
Published: August 2008

In 1991, the Lorraine Motel—infamous site of Martin Luther King Jr.’s assassination—reopened to the public under a refurbished name and identity: the National Civil Rights Museum (NCRM). This essay traces the motel’s transformation into the museum and argues that the physical conversion parallels three related changes that yield a degree of psychological refurbishment for various communities at the historical, economic, and cultural levels. By emphasizing the historical and cultural significance of the Lorraine Motel’s balcony, African American citizens were instrumental not only in preserving a site of tragedy but also in rebuilding, reframing, and renaming it as a more productive place of remembrance and collective identification. As a place of societal redemption, the NCRM represents a symbolic cleansing of King’s assassination site—a historical, economic, and cultural metamorphosis enacted through material transformation from vernacular to official culture.
False Models as Explanatory Engines
Authors: Hindriks Frank
Published: August 2008

Many models in economics are very unrealistic. At the same time, economists put a lot of effort into making their models more realistic. I argue that in many cases, including the Modigliani-Miller irrelevance theorem investigated in this paper, the purpose of this process of concretization is explanatory. When evaluated in combination with their assumptions, a highly unrealistic model may well be true. The purpose of relaxing an unrealistic assumption, then, need not be to move from a false model to a true one. Instead, it may be providing an explanation of some phenomenon by invoking the factor that figures in the assumption. This idea is developed in terms of the contrastive account of explanation. It is argued that economists use highly unrealistic assumptions to determine a contrast that is worth explaining. The process of concretization also motivates new explanatory questions. A high degree of explanatory power, then, may well be due to a high number of unrealistic assumptions. Thus, highly unrealistic models can be powerful explanatory engines.
A Preference for Selfish Preferences
Authors: Sánchez-Cuenca Ignacio
Published: August 2008

This article analyzes the problem of preference imputation in rational choice political science. I argue against the well-established practice in political science of assuming selfish preferences for purely methodological reasons, regardless of its empirical plausibility (this I call a preference for selfish preferences). Real motivations are overlooked due to difficulties of imputing preferences to agents in a non-arbitrary way in the political realm. I compare the problem of preference imputation in economic and political markets, and I show the harmful consequences of the preference for selfish preferences in the field of collective action.
When Are Strong Arguments Stronger Than Weak Arguments?
Authors: Lee Eun-Ju
Published: August 2008

The present experiment examined how the lack of individuating information affects message elaboration and conformity to group norms in text-based computer-mediated communication. Participants made decisions about choice dilemma scenarios and exchanged their arguments with three ostensible partners via computer. Consistent with the social identity model of deindividuation effects, those who had exchanged personal profiles with their partners prior to the discussion were better able to differentiate between strong and weak arguments and were more likely to make conformity decisions based on the message content than those who had not. On the other hand, those who had no identity cues were more likely to factor in group identification for their conformity decisions. Results suggest that less systematic message processing and greater reliance on normative considerations account for how deindividuation moderates the effects of argument strength on group conformity.
An evaluation tool of infection risk analysis for drainage systems in high-rise residential buildings
Authors: Cheng CL , Yen CJ , Wong LT , Ho KC
Published: August 2008

This study proposes a simple risk analysis tool and evaluation level for the probable infection due to a contaminated drainage stack in residential high-rise buildings in some Asian cities which have equivalent drainage systems. The methodology would follow the conception of FMEA (Failure Mode Effects Analysis). In particular, key risk factors including connections between appliance and stack, the plumbing system, ventilation, equipment life and maintenance were surveyed and used to evaluate the overall risk associated in high-rise residential buildings with Monte Carlo simulations. With the proposed tool, regional risks of infection due to the building drainage systems were estimated, with respect to the city building age and height profiles. The results showed that a city with a high-rise environment would associate a higher spreading risk due to the drainage system.

Practical applications: Following the outbreak of SARS (Severe Acute Respiratory Syndrome) in early 2003, the operational performance of drainage systems in high-rise residential buildings has become a major concern. The assessment system would be practical and sensible for evaluating the infection risk in building drainage systems for both existing buildings and new construction. The assessment tool may provide the government, designers and the occupants a source of reference to judge drainage system performance in either new construction or the existing building, so that improvements would be conducted.
Degree days for building energy management — presentation of a new data set
Authors: Layberry RL
Published: August 2008

Heating degree days are widely used in building energy management. For the construction of building performance lines, it is necessary to have the correct building base temperature with the meteorological station as close as possible to the building being monitored. In the UK, free degree day data is available on a monthly basis for 18 regions of the UK at a building base temperature of 15.5°C. This paper presents a new data set of degree days calculated for 77 regions, weekly and monthly, at a range of building base temperatures from 10.5°C to 20°C. The data is calculated using real hourly temperatures and is compared against degree days calculated using approximate equations. The data presented is free and is updated weekly at http://www.eci.ox.ac.uk/research/energy/degreedays.php

Practical applications: Degree days are widely used in building energy management; however, they are often not used due to the lack of availability of data for different time intervals, for appropriate weather stations and at building base temperatures other than 15.5°C. This paper presents and discusses a data set at high spatial resolution (77 UK stations) at both weekly and monthly time intervals for building base temperatures from 10.5°C to 20°C. This resource is more accurate than traditional sources due to having been calculated from hourly Meteorological Office data rather than daily maximum and minimum temperatures. The data is available online, is updated weekly and in a form such that it can be dynamically linked in to building energy management programs.
Modelling bulk water temperature in integrated collector storage systems
Authors: Currie JI , Garnier C. , Muneer T. , Grassie T. , Henderson D.
Published: August 2008

A simple low cost Integrated Collector Storage Solar Water Heater (ICS-SWH) was proposed for simulation in Scottish weather conditions. The system takes the form of a rectangular-shaped design incorporating the solar collector and storage tank into a single unit and the simplicity of construction and installation make this type of SWH a popular choice of solar water heater. A 3-month experimental and numerical study on the ICS-SWH was undertaken in order to compare the results with a newly developed macro model. Improvements were incorporated into the macro model by differentiating non-finned and finned collectors. The macro model was able to compare the water bulk temperature variation in different SWH collector material, with or without fins, internal temperature and external weather conditions for a given aspect ratio. Numerical results obtained by this new tool were found to be in close agreement with the experimental data.

Practical applications: Direct comparison of measured system performances is relatively straight forward; however, predicting the performance of an ICS-SWH at another location or with a different installation configuration is more challenging. A model able to predict water temperature in ICS-SWH would be a useful tool to allow any user to predict the performance of the installed SWH, depending on the orientation and location. Builders could use such a tool to demonstrate the performance of the ICS-SWH and the benefit of such installation.
Zinc Supplementation in Critically Ill Patients: A Key Pharmaconutrient?
Authors: Heyland Daren K. , Jones Naomi , Cvijanovich Natalie Z. , Wong Hector
Published: August 2008

The purpose of the present paper is to provide a rationale for zinc supplementation as a potential therapeutic agent in critically ill patients by describing its role in health and disease, conducting a systematic review of current randomized trials in critical care, considering optimum route and dose of administration, and making recommendations for future research. Normal zinc homeostasis is required for a functional immune system, adequate antioxidant capacity, glucose homeostasis, and wound healing. In addition, zinc is a required cofactor for many enzymes, transcription factors, and replication factors. In non–critically ill patients, zinc supplementation has been associated with an improvement in markers of immune function. In critically ill patients, only 4 randomized trials have examined the effect of zinc supplementation on clinical outcomes. When all 4 studies were aggregated, zinc supplementation was associated with a nonsignificant reduction in mortality (relative risk = 0.63, 95% confidence intervals 0.25‐1.59, P = .33) and length of stay in intensive care (–0.35 days, –0.85 to 0.15; P = .17). Thus, because of the paucity of clinical data, there is inadequate evidence to recommend the routine use of high‐dose zinc supplementation in the critically ill. A first step would be to determine the optimal dose that has a maximal positive effect on underlying inflammatory, immunologic, and metabolic processes yet is safe and tolerated by critically ill patients. Subsequently, large, rigorously designed, randomized trials are required to elucidate the efficacy of such doses of zinc supplementation in this patient population.
Chronic Lateral Ankle Instability
Authors: Choi Woo Jin , Lee Jin Woo , Han Seung Hwan , Kim Bom Soo , Lee Su Keon
Published: August 2008

Background

There has been no attempt to correlate the type and number of intra-articular lesions with the results of ligament reconstruction for chronic lateral ankle instability.

Hypothesis

Certain intra-articular lesions affect the clinical outcome of ligament reconstruction.

Study Design

Case series; Level of evidence, 4.

Methods

Sixty-five ankles from 64 patients underwent a modified Broström operation for chronic lateral ankle instability with a mean follow-up of 28.7 months (range, 12–67). The results were assessed according to the Karlsson-Peterson Ankle Score. The type of intra-articular lesions and the association of clinical outcome were investigated using Pearson's correlation coefficient and multivariate logistic regression analysis.

Results

The average Karlsson-Peterson Ankle Score was improved from 53 ± 14.63 preoperatively to 85.21 ±11.97 at final follow-up ( P < .001). Five different intra-articular lesions were described in 63 ankles (96.9%), and the ankle score negatively correlated with the number of lesions ( r = −.604; P < .001). Multivariate logistic regression showed that syndesmosis widening (odds ratio, 11.1; 95% confidence interval: 2.2–55.4; P = .003), osteochondral lesions of the talus (odds ratio, 8.5; 95% confidence interval: 1.7–42.3; P = .008), and ossicles (odds ratio, 4.5; 95% confidence interval: 1.0–20.2; P = .046) are significant predictors of unsatisfactory results after ligament reconstruction.

Conclusion

Arthroscopic diagnosis and treatment of intra-articular lesions associated with chronic lateral ankle instability is a safe and effective method. The presence of any combination of associated intra-articular lesions can result in a poor outcome.
Effect on Tissue Differentiation and Articular Cartilage Degradation of a Polymer Meniscus Implant
Authors: Welsing Roy T. C. , van Tienen Tony G. , Ramrattan Navin , Heijkants Ralf , Schouten Arend Jan , Veth René P. H. , Buma Pieter
Published: August 2008

Background

Replacement of the meniscus by an implant could potentially avoid cartilage degeneration.

Hypothesis

An implant of degradable polycaprolacton-polyurethane should act as a temporary scaffold enabling regeneration of a new meniscus by slow degradation of the polymer and simultaneous in-growth and differentiation of tissues into the typical cartilage-like tissue of the meniscus.

Study Design

Controlled laboratory study.

Methods

In 13 dogs’ knees, the lateral meniscus was replaced with a porous polymer implant (6 and 7 for 6- and 24-month follow-up, respectively); in 7 knees only a meniscectomy was performed. In 6 knees, no surgery was performed. After 6 and 24 months, the implants and the articular cartilage were histologically evaluated. Compression-stress tests were performed on implant biopsy specimens.

Results

The implants were fully integrated into the tissue without formation of a capsule. The foreign body reaction did not exceed grade I. Differentiation from fibrous- to cartilage-like tissue was pronounced after 24 months. Viable cells were particularly absent after 24 months in central parts of the most anterior part of the scaffold. The mechanical properties of the implants were intermediate between the scaffold before implantation and native meniscus tissue and were not different between 6 and 24 months. After both 6 and 24 months, small areas of the implant were not covered with tissue. Cartilage degeneration was not prevented.

Conclusion

A final remodeling of tissue into neomeniscus tissue could not take place since the original structure of the polymer was still present after 24 months. The implant did not prevent cartilage degradation. Several factors are discussed that may be responsible for this.

Clinical Relevance

Although clinical application of a polymer implant for the replacement of the entire meniscus is not supported by this study, the authors strongly believe in the concept, but further improvements in the implant and surgical technique are needed before such an implant can be recommended for human clinical use.
Type I Collagen α1 Sp1 Polymorphism and the Risk of Cruciate Ligament Ruptures or Shoulder Dislocations
Authors: Khoschnau Shwan , Melhus Håkan , Jacobson Annica , Rahme Hans , Bengtsson Henrik , Ribom Eva , Grundberg Elin , Mallmin Hans , Michaëlsson Karl
Published: August 2008

Background

Cruciate ligament ruptures and shoulder dislocations are often caused by trauma, but predisposing intrinsic factors might also influence the risk. These injuries are more common in those with a previously injured sibling, an observation that might indicate a genetic predisposition. It is well known that polymorphisms in the collagen I gene are associated not only with osteoporosis and osteoporotic fracture risk, but also with osteoarthritis.

Hypothesis

Because collagen I is abundant in ligaments and tendons, the authors hypothesized that collagen I α1 Sp1 polymorphism also was related to the occurrence of cruciate ligament ruptures and shoulder dislocations.

Study Design

Case-control study; Level of evidence, 3.

Methods

A total of 358 patients and 325 randomly selected population-based female controls were included in the study. Of the cases, 233 had a cruciate ligament rupture and 126 had had a shoulder dislocation. Age-adjusted odds ratios (ORs) with 95% confidence intervals (CIs) estimated by unconditional logistic regression were used as measures of association.

Results

Compared with the homozygous SS category, the heterozygous participants displayed a similar risk (OR, 1.06; 95% CI, 0.76–1.49), whereas the ss genotype was underrepresented in the injured population compared with the controls (OR, 0.15; 95% CI, 0.03–0.68). This latter estimate was similar for both cruciate ligament ruptures and shoulder dislocations, and was furthermore not modified by general joint laxity.

Conclusion

The authors found a substantially decreased risk of these injuries associated with collagen type I α1 Sp1 polymorphism. The study might encourage other investigators to consider further research in the area of genes and soft tissue injuries.
Experimental Research on Outgassing Rate of Glass Fiber Reinforced Plastics with Different Surface Topographies
Authors: Xiao Y.M. , Zhu H.M. , Feng H.D. , Xu L.
Published: August 2008

In this paper, an experimental system based on the differential pressure method was designed to measure the outgassing rate of glass fiber reinforced plastics (GFRP) with different surface topographies. Two GFRP samples with different surface topographies were fabricated with two different mesh numbers of abrasive paper, #500 and #100. The surface topographies and roughnesses of the GFRP samples were measured by a scanning probe microscope. The outgassing rates of the GFRP samples with different surface topographies were tested at different temperatures. It is demonstrated from experimental results that the higher GFRP temperature leads to the higher pressure range of the gas in the measurement chamber, accordingly the greater gas quantity released from GFRP, and consequently the larger outgassing rate of GFRP, and that the larger surface roughness of GFRP causes the greater outgassing rate.
Mixed-mode Fracture Toughness and Kink Formation of Woven Glass Reinforced Epoxy Composites
Authors: Çolak Fatih M. , Dağhan Behçet , Şahin Ömer Sinan
Published: August 2008

In this study the fracture behavior of woven glass fiber reinforced epoxy composites with trough thickness crack oriented at different angles were investigated. The composite plates consisting of five layers have a thickness of 1.2 mm. The trough cracks were formed at the center of the specimens with lengths of 5 mm, 7 mm and 9 mm. The fracture behavior of the composites, subjected to tensile loading and kink formation, were investigated. The fracture toughness of the composite specimens was determined by using both initial notch depth and the compliance method. The experimental results were presented in graphical form.
Behavior of Short Carbon Fibers in Cfiber/Si3N4 Composites by Hot Pressed Sintering
Authors: Xiaoyan Wang  , Dongmei Zhu  , Peng Li  , Xiaolei Su  , Fa Luo  , Wancheng Zhou
Published: August 2008

Cfiber/Si3N4 composites were prepared by introducing short carbon fibers into a mixture of silicon nitride and sintering additives (La2O3—Y2O 3) by hot pressed sintering. The effects of fibers on microstructure and mechanical properties of composites were discussed after higher temperature sintering. The corrosion of carbon fibers was manifested in two characteristic ways: (1) the internal fiber had exfoliative structure and some serious cavities were easily found at the interfaces between Si3N4 matrix and carbon fibers; (2) the fiber surface was covered by β-Si3N 4 crystallites. When the fiber content varied from 0 to 1 wt%, the fracture toughness increased from 6.6 MPa · m1/2 to 8.01 MPa· m 1/2. The flexural strength decreased from 638.14 MPa to 584.63 MPa with the rise of short fiber content.
Chemical Resistance and Tensile Properties of Unsaturated Polyester and Epoxy/PMMA Blend Coated Ceiba pentandra
Authors: Venkata Reddy G. , Shobha Rani T. , Khanam P.N. , John K. , Venkata Naidu S.
Published: August 2008

The naturally occurring fabric belonging to the species Ceiba pentandra, which is commonly known as kapok, is abundantly available in India. The surface of alkali-treated and untreated kapok fabric was coated with unsaturated polyester, epoxy resin, polymethyl methacrylate (PMMA) and epoxy/PMMA blend matrix. The chemical resistance of this fabric to different chemicals and tensile properties was studied. The effect of alkali-treatment (NaOH) on the tensile properties of the fabric was also studied. It was observed that the coated fabric specimens show better chemical resistance and tensile properties than uncoated ones. The tensile properties increased on alkali-treated fabric, which was identified from the results. Epoxy/PMMA coated fabric specimens have better chemical resistance and tensile properties compared to other matrix materials. These observations indicate that the Kapok fabric and the epoxy/PMMA blend are suitable materials for making eco-friendly composites.
Evaluation of Methods for Stiffness Predictions of Polymer/Clay Nanocomposites
Authors: Wang Gong-Tao , Liu Hong-Yuan , Yu Zhong-Zhen , Mai Yiu-Wing
Published: August 2008

This article presents a critical review and evaluation of several mechanics models which are commonly used for elastic stiffness predictions of polymer/clay nanocomposites (PCNs). In particular, the assumptions and limitations of these models and formulas were examined. Stiffness predictions were compared to published data in order to assess their applicability and effectiveness to real PCNs. Whilst a more complex model can achieve better agreement with experimental data, more parameters, which must be obtained by separate independent tests, are always required. This may lead to increasing errors for model applications. It is shown that meso-mechanics models due to Mori—Tanaka, Ji et al. and Luo—Daniel give the best overall predictions, with due consideration of the dispersion and orientation effects of the platelets embedded in a polymer matrix.
Development and Characterization of Amine Terminated Poly(Ethylene Glycol) Benzoate Modified Epoxy and E Glass Fiber Composites
Authors: Jena Rajeeb K. , Bhat A.H. , Maji S. , Behera D. , Banthia A.K.
Published: August 2008

The E glass woven fabrics have been used as a reinforcing agent with amine terminated poly(ethylene glycol) benzoate (ATPEGB) modified epoxy as a matrix, for the preparation of fiber reinforced plastic (FRP) composites. The composite materials so obtained were subjected to dynamic mechanical analysis at a fixed frequency of 1 Hz. The volume fraction of glass was about 0.45. The concentration of ATPEGB in the matrix was varied gradually from 0 to 30 phr (phr stands for parts per hundred parts of resin). To investigate the effect of ATPEGB concentration on the dynamic mechanical properties of the composites, it was found that the tan δ peak temperature and storage modulus gradually decrease with incorporation of ATPEGB. However, the tan δ peak value increases upto 10 phr of ATPEGB concentration and decreases thereafter. Flexural strength of the composites increases slightly up to 10 phr of ATPEGB concentration and decreases thereafter. However, the impact strength of the composites increases significantly up to 10 phr of ATPEGB concentration and decreases thereafter. Scanning electron microscope (SEM) analysis of the fracture surface indicates massive plastic deformation in modified epoxy-based composites.
Non-Linear Analysis of a Ductile Adhesive in the Single Lap Joint Under Tensile Loading
Authors: Kadioglu Ferhat , Adams Robert
Published: August 2008

In this article, potential use of ductile adhesives in structural applications is taken into consideration and their possible advantages over traditional structural adhesives are discussed. For this purpose, the performance of a very ductile adhesive with high strain to failure was investigated in the single lap joint (SLJ) configuration in tensile loading, and the joint was modeled using the finite element method (FEM) to analyze its non-linear solutions. In analyzing the joint, consideration is given to the stress distributions in the adhesive layer and the load to failure was predicted. The predicted values were well in agreement with the previous experimental results, and the stress distributions of the ductile adhesive differed in many respects from traditional structural adhesives. In order to see the differences, a structural modern epoxy has also been analyzed.
An Inverse Approach Based on Laminate Theory to Calculate the Mechanical Properties of Braided Composites
Authors: Zebdi Oussama , Boukhili Rachid , Trochu Francçois
Published: August 2008

A new approach based on plate laminate theory (PLT) is developed to calculate the mechanical properties of woven and braided composites. It supposes that, for each woven or braided composite oriented at ±θ, there is an equivalent ±θ angle-ply laminate made out of two unidirectional plies. An inverse algorithm based on PLT was developed to calculate, from the known mechanical characteristics of a composite reinforced by engineering fabrics, the properties of the mechanically equivalent angle-plies. The virtual angle-ply and cross-ply laminates obtained by inverse calculation include the effects of undulation and strand shear. The difference in properties between experience and theory is clear, especially for Poisson’s ratio. Comparisons performed between numerical predictions and experimental tests have shown a good correlation.
Mestiza Double Consciousness
Authors: Falcón Sylvanna M.
Published: August 2008

In this article, the author proposes a confluence of W. E. B. Du Bois's “double consciousness” (1903/1982) and Gloria Anzaldúa's “mestiza consciousness” (1989) to analyze the experiences of three Afro-Peruvian women. The merging of double and mestiza consciousness is necessary to holistically understand how gendered racism shapes their lives and why they have a desire to forge transnational solidarity with other women in the African Diaspora of the Americas. By gendering double consciousness and expanding mestiza consciousness beyond the United States and the U.S.-Mexico borderlands, we can better understand how women's agency plays a role in what the author refers to as mestiza double consciousness.
Intravenous Iron Therapy: A Summary of Treatment Options and Review of Guidelines
Authors: Silverstein Scott B. , Gilreath Jeffrey A. , Rodgers George M.
Published: August 2008

Iron replacement for iron-deficiency anemia has historically been accomplished with the use of oral iron therapy. Although oral iron is appropriate for most iron-deficiency anemia patients, many patients do not respond to or may be intolerant of oral iron, or may experience bleeding of sufficient magnitude to require higher iron doses than that achievable with oral iron. Intravenous iron therapy is a useful option for these latter patients. Three intravenous iron products are recommended: low-molecular weight iron dextran (INFeD), ferric gluconate (Ferrlecit), and iron sucrose (Venofer). These intravenous iron products have superior safety profiles compared to high-molecular weight iron dextran. The Food and Drug Administration's approval of erythropoietic-stimulating agents to treat certain types of anemia has increased usage of intravenous iron for functional iron deficiency. This review summarizes the current status of intravenous iron products and discusses their advantages and disadvantages in treating both absolute and functional iron deficiency.
Cervical Screening in Canadian First Nation Cree Women
Authors: O'Brien Beverley A. , Mill Judy , Wilson Tina
Published: August 2008

Purpose: Attitudes and beliefs of First Nation Cree women living in a reserve community were explored to gain insights into how cervical screening could be better utilized. Method: Focused ethnography utilizing participant observation and interviews ( n = 8) with participants having experience with cervical screening and/or cancer was conducted. Results: Women did not believe they had adequate information and were resistant to screening because of embarrassment caused by the procedure and fear of cancer, which was viewed as a “death sentence.” Conclusions: Challenges faced by First Nation Cree women when contemplating cervical screening are presented. Nursing sensitivity is needed to strategize access to cervical screening that is culturally appropriate.
Social Relationships Among Family Caregivers
Authors: Phillips Linda R. , Crist Janice
Published: August 2008

Sometimes, clinicians assume caregivers in cultural groups believed to have large social networks and strong social support need little intervention from health professionals. This longitudinal study tests five hypotheses about the social relationships of Mexican American compared to non-Hispanic White caregivers and whether negative changes in social support affect perceived health. The sample includes 66 Mexican American and 92 non-Hispanic White caregivers. Findings show that social networks and social support are similar at baseline and similarly stable for 1 year. Negative changes in social support are correlated with poorer health perceptions. Findings underscore the importance of designing interventions that are culturally competent based on what the caregiver is experiencing rather than cultural stereotypes.
Business Simulations and Cognitive Learning
Authors: Anderson Philip H. , Lawton Leigh
Published: August 2008

This article focuses on the research associated with the assessment of the cognitive learning that occurs through participation in a simulation exercise. It summarizes the objective evidence regarding cognitive learning versus the perceptions of cognitive learning achieved as reported by participants and instructors. The authors also explain why little progress has occurred in objectively assessing cognitive learning in the past 25 years and provide potential options for filling this deficiency.
Whiteness and the Polarization of American Politics
Authors: Olson Joel
Published: August 2008

Scholars tend to agree that American politics has become polarized along partisan and ideological lines, yet the causes of polarization are in much dispute. The author argues that polarization and the culture wars are a consequence, in part, of the changing nature of white identity after the civil rights movement. The transformation of whiteness from a form of social standing to a norm produced ressentiment among whites, which Republican strategists mobilized by depicting Democrats as the party of intellectual snobs and undeserving rabble and the GOP as the party of the virtuous middle. Normalizing this middle and the snobs as white polarized whites along partisan and ideological lines, creating an incentive to win votes by appealing to hot-button cultural issues such as welfare, abortion, and gay marriage.
Meaningful Citizen Engagement in Science and Technology
Authors: Powell Maria C. , Colin Mathilde
Published: August 2008

Citizen engagement in scientific and technological issues is in vogue in recent years, and a variety of projects intended to engage citizens in science and technology is occurring worldwide. However, few academics and governments attempting to “engage in engagement” are clear about their goals and desired outcomes, and whether or not the processes they facilitate are likely to meet these ends. What are the goals—explicit and implicit—of institutionally sponsored projects that aim to engage lay citizens in science and technology? Are these exercises likely to meet these goals? and what kinds of processes could nurture more meaningful engagement, what are the barriers to this kind of engagement, and how might these barriers be overcome? Based on the experience of the authors, this article explores these questions and provides 10 recommendations for more meaningful engagement of citizens in science and technology.
Power, Punishment and Reconciliation in the Political and Social Thought of Simone Weil
Authors: Hamilton Christopher
Published: August 2008

The aim of this article is to explore some aspects of the significance of Simone Weil's work for the question of reconciliation. Focusing on Weil's notion of power, and investigating its plausibility, the article argues that her thinking is less useful than is sometimes supposed for grounding a cosmopolitan ethic. It further argues that Weil's philosophical outlook, with its emphasis on loving everything that happens as an expression of God's will, is in danger of being incapable of taking seriously others' suffering. By picking up on the themes of punishment and forgiveness in her work, it is contended that she does not have readily available a proper conception in this context of our status as political agents. However, it is suggested that there is to be found a more promising line on reconciliation in her work in the notion of luck, and that this concept is one that, more generally, may have a more important role to play in understanding reconciliation than is often supposed.
Shame, Guilt and Reconciliation after War
Authors: Lu Catherine
Published: August 2008

How do experiences of shame and guilt shape or reflect the ways in which the vanquished are reconciled (or not) to the new world order established by the victors? Shame and guilt are universal experiences in the emotional landscape of post-war politics, albeit for different reasons and with radically different political effects. An examination of Germany after 1918 and of Japan after 1945 reveals that experiences of shame and guilt may be pivotal for creating conditions of possibility for reconciliation marked by political and moral transformation. This transformative potential of shame and guilt, however, is a double-edged sword. In threatening old identities, values and beliefs, experiences of shame and guilt may provoke defensive, reactionary and violent political responses, and thus may precipitate hideous rather than salutary transformations. Political leadership and political culture are crucial factors in shaping the kind of reconciliation — reactionary or transformative — as well as the specific nature of transformations that experiences of shame and guilt may motivate the vanquished to pursue.