bluuebunny/crossref_metadata_2025 huggingface dataset:
Preoperative autologous blood donation versus intraoperative blood salvage: intraindividual analyses and modeling of efficacy in 1103 patients
Authors: Singbartl Guenter , Schreiber Joerg , Singbartl Kai
Published: July 2009

BACKGROUND: Preoperative autologous blood donation (PABD) and intraoperative blood salvage (IBS) represent established blood conservation measures. However, data comparing PABD to IBS are very sparse.

STUDY DESIGN AND METHODS: We analyzed data from 1103 patients undergoing PABD and subsequent major orthopedic surgery in one center. We then used a validated model to compare PABD to IBS. We calculated maximal allowable blood losses (MABLs) for both IBS and PABD. We also identified criteria for efficacious use of either PABD or IBS. Our calculations were based on exclusive application of either technique, complete exhaustion of predeposited or salvaged blood, and one round of IBS.

RESULTS: The vast majority of patients would have tolerated greater MABLs if subjected to IBS rather than PABD (425 of 432 with 1 PABD unit, 580 of 664 patients with 2 PABD units, 3 of 7 patients with 3 PABD units). For a few patients, however, our model demonstrated greater MABL with PABD than with IBS. These patients were characterized by 1) lower initial hematocrit (Hct), 2) recovery from PABD with return to baseline Hct or above by the time of surgery, and 3) longer time between first PABD and surgery.

CONCLUSION: IBS appears to be the superior blood conservation technique if PABD cannot be performed under optimal conditions. Tolerable predonation anemia and sufficient time for regeneration appear to be crucial for post‐PABD erythropoiesis. If these goals cannot be accomplished, PABD should be abandoned and be replaced by IBS.
Estimation of sensitivity and specificity of several Trypanosoma cruzi antibody assays in blood donors in Argentina
Authors: Remesar Mirta C. , Gamba Cecilia , Colaianni Ivana F. , Puppo Mónica , Sartor Paula A. , Murphy Edward L. , Neilands Torsten B. , Ridolfi María A. , Leguizamón M. Susana , Kuperman Silvina , Del Pozo Ana E.
Published: July 2009

BACKGROUND: The absence of a gold standard test for Trypanosoma cruzi antibodies represents a problem not only for the evaluation of screening tests, but also for appropriate blood donor counseling. The aim of this study was to estimate the sensitivity and specificity of multiple blood donor screening tests for T. cruzi antibodies in Argentina.

STUDY DESIGN AND METHODS: From June 2006 to March 2007 a sample of 1455 blood donors was recruited from two blood banks in Chaco province, an area of Argentina with highly endemic T. cruzi infection. Samples were tested by three epimastigote lysate enzyme immunoassays (EIAs), one recombinant antigen EIA, two indirect hemagglutination assay (IHA) tests, a particle agglutination assay (PA), and a research trans‐sialidase inhibition assay (TIA). Sensitivity and specificity were estimated using latent class analysis (LCA).

RESULTS: LCA estimated the consensus prevalence of T. cruzi infection at 24.5%. Interassay correlation was higher among the four EIA tests and TIA compared to IHA tests. Assay sensitivities varied from 96 to 99.7 for different EIAs, 91% for TIA, 84% for PA, and 66 to 74% for IHA tests. Relative to the LCA, assay specificities were from 96% to almost 100%.

CONCLUSION: Based on the comparison of several tests in a large population from an endemic area for T. cruzi infection, our data showed an adequate sensitivity for EIA tests in contrast to PA and IHA assays. The latter tests should no longer be used for blood donor screening.
Getting Dirty‐Minded: Implementing Presidential Policy Agendas Administratively
Authors: Durant Robert F.
Published: July 2009

With polarization in Congress persistent, with staggering issues and international threats facing the nation, and with fiscal stress an enduring fact of life, presidents have for decades turned to the tools of the administrative presidency to advance and implement their policy agendas. As the Barack Obama administration completed its first six months in office amid great challenges and hopes, the president was no exception in counting on his appointees to wield the tools of the administrative presidency to advance his protean policy agenda for America. This essay offers 10 research‐based lessons for new appointees charged with advancing presidential agendas administratively to ponder as they do so.
Financial Regulation in the United States: Lessons from History
Authors: Peretz Paul , Schroedel Jean Reith
Published: July 2009

History is institutional memory writ large. One looks at economic history to see what problems recur, what causes them to recur, what solutions have worked best in the past, and which interventions have made the problems worse. The authors argue that a moderately complex interaction between the workings of the financial sector, the way in which the political system is organized, and the administration of regulation makes perfect regulation of the financial sector extremely unlikely. Many of these problems arise as a result of conflicting incentives for those participating in and regulating the financial field. The authors find that some proposed solutions have improved matters but have costs, and that some proposed solutions have actually worsened problems in the financial sector.

Peoples and governments never have learned anything from history, or acted on principles deduced from it.

—Georg Wilhelm Friedrich Hegel, 1837
The Federal Reserve System and the Credit Crisis
Authors: Corder J. Kevin
Published: July 2009

The Federal Reserve System struggled to maintain order in U.S. credit markets as rapid declines in home prices led to huge write‐downs in the value of mortgage‐backed securities held by financial institutions. The Fed could have taken a number of steps—in the mortgage market or through broader regulatory actions—to either preempt or mitigate the impact of this market disruption. Broader regulatory actions—in the mortgage market, of risk taking by financial institutions, or in the form of actions to limit the contagion of crisis—imply fundamental changes at the Fed. The network of actors with a stake in broader regulatory action is powerful and highly resistant to regulatory scrutiny. The statutory mission of the Fed—especially its commitment to stable prices—could be jeopardized by a broad and explicit mandate to provide liquidity to a wide range of vulnerable financial institutions.
Federal Use of Implied Guarantees: Some Preliminary Lessons from the Current Financial Distress
Authors: Phaup Marvin
Published: July 2009

The U.S. financial crisis and recession that began in 2007 poses profound challenges for public policy and administration. It also provides useful information about the effects of economic policies. This paper considers the implications of current developments for the use of implied guarantees as an instrument of public policy. It draws on experience with Fannie Mae and Freddie Mac to argue that implied federal guarantees have a severe disadvantage. Their costs are largely unmeasured, unrecognized in the budget, and unmanaged. Yet their use appears to be increasing in the current crisis. To minimize the costs of the expanded financial safety net, government should measure and manage those costs more effectively. To that end, this paper proposes new budgetary treatments of federal implied guarantees.
State of Change: Global Turmoil and Government Reinvention
Authors: Datz Giselle
Published: July 2009

The current global credit crisis is unfolding in a context in which new dynamics in the engagement of the public sector and the market are taking shape. This article explores some of these dynamics, especially the reemergence of (re)nationalization initiatives, as well as the growing use of private methodologies for asset management on the part of some governments, which behave as both financial market players and domestic economic stabilizers. Hence, the article discusses the return of the state as a traditional “public leviathan” involved in financial regulation, as well as the work of sovereign wealth funds. The author concludes that at the heart of capitalism's endurance lies this diversity of public responses, which ultimately reveal governments' adaptable agendas and heterogeneous tasks.

I think that capitalism, wisely managed, can probably be made more efficient for attaining economic ends than any alternative system yet in sight, but that in itself it is in many ways extremely objectionable. Our problem is to work out a social organisation which shall be as efficient as possible without offending our notions of a satisfactory way of life.

—John Maynard Keynes, The End of Laissez‐Faire, 1926

The all‐powerful market which is always right is finished.…We have to have a new balance between the state and the market.

—French president Nicolas Sarkozy, 2008
Does E‐Government Measure Up to E‐Business? Comparing End User Perceptions of U.S. Federal Government and E‐Business Web Sites
Authors: Morgeson Forrest V. , Mithas Sunil
Published: July 2009

This paper examines the federal government's success in implementing and providing high‐quality service through e‐government, something that has received very little attention. We define quality from the perspective of the end users of federal agency Web sites, as measured through customer survey data. Using data from the American Customer Satisfaction Index, we compare the performance of federal agency Web sites across a range of relevant variables with a private sector equivalent, e‐business Web sites. Our findings suggest that federal e‐government Web sites are not yet, in the aggregate, providing the same level of quality as their e‐business counterparts. We also find significant variability among federal agencies. We discuss the implications of these findings for e‐government performance measurement, performance benchmarking, and the market‐centered theories of administrative reform that are driving e‐government and similar transformations of government practice.
The Impact of Large Changes in Asset Prices on Intra‐Market Correlations in the Domestic and International Markets
Authors: Ronn Ehud I. , Sayrak Akin , Tompaidis Stathis
Published: July 2009

We consider the impact of “large” changes in asset prices on intra‐market correlations in domestic and international markets. Assuming normally distributed asset returns, we show that the absolute magnitude of the correlation, conditional on a change is greater than or equal to a given absolute size of one of the variables, is monotonically increasing in the magnitude of that absolute change. Empirical tests using domestic and international‐market data support this theoretical result. These results have significant implications for portfolio management, hedging interest rate risk, tests of asset pricing models, Roll's concern with asset pricing models' explanatory power, and implementation of Value‐at‐Risk.
Hypertrophic Cardiomyopathy
Authors: TOWBIN JEFFREY A.
Published: July 2009

Background: Hypertrophic cardiomyopathy (HCM) is one of the most common inherited cardiac disorders, with a prevalence in young adults of one in 500 and is defined by its wall thickening.

Methods: This chapter of the supplement will present major clinical impacts of this disorder in its predilection to be inherited; its reputation as the most common cause of sudden death in young, healthy, athletic individuals; and its potential to develop heart failure due to either diastolic or systolic dysfunction, so‐called “burned out” HCM. Underlying etiologies; diversity of morphologic, functional, and clinical features; and variable age of onset that differentiate the childhood from the adult form of disease will be discussed based on the literature and clinical experience.

Results: In children less than 1 year of age, hypertrophy associated with systolic dysfunction is common. In contradistinction, among apparently healthy young adults, the prevalence of echcocardiographically defined HCM was reported to be as high as 0.2% and associated with diastolic dysfunction. In addition, overlaping disorders such as infiltrative and energy‐dependent forms of HCM coexist with other atypical features in childhood, further confounding the presentations, treatments, and outcomes compared to adult disease.

Conclusion: HCM in childhood has a variety of etiologies which may influence diagnostic testing, treatments, and outcomes.
Sudden Cardiac Death in Dilated Cardiomyopathies
Authors: HAMILTON ROBERT M. , AZEVEDO EDUARDO R.
Published: July 2009

Dilated cardiomyopathy (DCM) is the most prevalent form of cardiomyopathy, and sudden cardiac death (SCD) remains a common event in young patients. The disorder is highly heterogeneous and pediatric DCM often differs from adult DCM in etiologies, risk factors, and prognosis. Prognosis may be improving, likely secondary to specialized management. Both traditional and novel markers of risk have been studied in adults and are beginning to be applied to children with DCM. The major therapy for patients considered at risk remains implantable cardioverter‐defibrillator (ICD) placement, although frequently this functions as a bridge to eventual transplantation.
The Long QT Syndrome and Catecholaminergic Polymorphic Ventricular Tachycardia*
Authors: MONTEFORTE NICOLA , PRIORI SILVIA G.
Published: July 2009

Thanks to the contribution of molecular genetics, the genetic bases, the pathogenesis and genotype–phenotype correlation of diseases such as the long QT syndrome and catecholaminergic polymorphic ventricular tachycardia have been progressively unveiled and show an extremely high degree of genetic heterogeneity. Data from clinical registries are summarized together with the recommendations provided in clinical practice guidelines for management of patients with these diseases. Furthermore the evidence supporting the importance of genetic analysis for risk stratification and therapy selections is reviewed.
Congenital Coronary Artery Abnormalities Predisposing to Sudden Cardiac Death
Authors: FROMMELT PETER C.
Published: July 2009

Isolated congenital coronary artery anomalies (CCAAs) are a rare but well‐described cause of sudden cardiac death (SCD). Anomalous origin of a coronary artery from the opposite sinus has been most frequently associated with myocardial ischemia, ventricular arrhythmias, and sudden death, particularly when the anomalous coronary courses between the great arteries. Importantly, symptoms occur in only about 50% of people with CCAA who subsequently have SCD. Echocardiography is effective in prospectively identifying these coronary artery abnormalities but requires sophisticated echo equipment and a laboratory examination with targeted, high‐quality imaging. Although surgical intervention for some forms of CCAA is feasible with good early results and is clearly indicated for symptomatic patients, no clear best practice has been established for the management of those identified serendipitously without symptoms.
Implantable Cardioverter Defibrillator‐Related Complications in the Pediatric Population
Authors: SHAH MAULLY J.
Published: July 2009

Background: The recognition that implantable cardioverter‐defibrillator (ICD) therapy in children can prolong life coupled with the development of smaller devices and transvenous lead technology has increased the number of ICDs implanted in children and young adults.

Methods: ICD complications in the pediatric population are reviewed.

Results: ICD complications in the pediatric population include those related to the implantation procedure, the ICD system, as well as psychosocial issues. Inappropriate ICD therapy and ICD lead failures are the most frequent complications.

Conclusion: Identifying complications is the prerequisite for advances in ICD technology and effective management strategies need to be developed to avoid their recurrence.
State of Postmortem Genetic Testing Known as the Cardiac Channel Molecular Autopsy in the Forensic Evaluation of Unexplained Sudden Cardiac Death in the Young
Authors: Ackerman Michael J.
Published: July 2009

Background: Thousands of infants, children, adolescents, and young adults die sudden and unexpectedly each year in the United States. A significant proportion are autopsy negative and are classified as autopsy negative sudden unexplained death (SUD) after the first year of life and as sudden infant death syndrome (SIDS) if prior to their first birthday. Postmortem genetic testing known as the cardiac channel molecular autopsy is capable of identifying the subset of channelopathic SUD/SIDS.

Methods: Review of the literature and analysis of the state of such postmortem genetic testing in the evaluation of SUD/SIDS.

Results: Although still confined to anecdotal reports, relatively small case series of coroner/medical examiner‐referred cases of SUD/SIDS, and one population‐based cohort of SIDS, it is estimated that approximately 25–35% of autopsy‐negative SUD and approximately 10% of SIDS may stem from mutations in either long QT syndrome (LQTS)‐ or catecholaminergic polymorphic ventricular tachycardia (CPVT)‐susceptibility genes.

Discussion: Whether the cardiac channel molecular autopsy should become the standard of care in the postmortem evaluation of autopsy negative SUD or SIDS will require further scrutiny. Cost effectiveness analyses of a more intense postmortem focus on the decedent compared to the current battery of tests recommended for the deceased SUD victim's first degree relatives should be performed.

Conclusion: If deemed justified to upgrade such postmortem genetic testing from “investigational” to clinically indicated, uniform “standard operating procedures” to ensure that tissue is acquired and archived in a manner that is “DNA friendly” and insurance coverage that extends beyond one's final breath will be needed.
Sudden Cardiac Arrest in the Young Due to Inherited Arrhythmias: The Importance of Family Care
Authors: VINCENT G. MICHAEL
Published: July 2009

Background: Sudden cardiac arrest in the young is always an extremely tragic event, producing enormous stress and anxiety in the family. When the event is due to an inherited cardiac arrhythmia, the additional concerns and questions about who else is affected and who will die next can become overwhelming to both the nuclear and the extended family. Identification and screening of the family members are necessary in order to find and treat presymptomatic members and prevent sudden death.

Methods: Guidelines and strategies for care of the extended family are presented.

Results: Pedigree development and expansion, followed by prospective contacting of family members and screening by phenotyping and genotyping, allow recognition and treatment of many mutation carriers who would not otherwise come to medical attention unless they develop a serious cardiac event. Presymptomatic treatment of affected members is highly efficacious and prevents sudden deaths.

Conclusions: Sudden cardiac arrest due to inherited arrhythmia disorders can be prevented by prospective, structured evaluation of the extended family, allowing effective, presymptomatic, and prophylactic treatment of the affected members to be provided.
Functional polymorphism in H2BFWT‐5′UTR is associated with susceptibility to male infertility
Authors: Lee Jinu , Park Hee Suk , Kim Hwan Hee , Yun Yeo‐Jin , Lee Dong Ryul , Lee Suman
Published: July 2009

H2B histone family, member W, testis‐specific (H2BFWT) gene encodes a testis‐specific histone that becomes incorporated into sperm chromatin. A male infertility‐associated single nucleotide polymorphism (−9C > T) within the 5′ untranslated region (5′UTR) of the H2BFWT gene was identified by direct sequencing. Statistical association studies showed the polymorphism significantly associated with male infertility (n= 442, P= 0.0157), especially in non‐azoospermia (n= 262, P= 0.018). Furthermore, this polymorphism is also associated with sperm parameters, especially sperm count (n= 164, P= 0.0127) and vitality (n= 164, P= 0.0076). We investigated how the genetic variant at 5′UTR confers susceptibility to non‐azoospermia. Western blotting of His‐tag H2BFWT revealed a difference at the translational level between ‐9T and the wild‐type −9C in the absence of change at the transcriptional level. Reporter assays showed that this reducing translational change originated from an upstream open reading frame (uORF) generated by the −9C to −9T change. Finally, in vivo H2BFWT expression in sperm was significantly dependent on the −9C > T genotype from non‐azoospermia (P= 0.0061). Therefore, this polymorphism could affect the translational efficiency of a quantitatively important histone protein by the uORF. Our data implicate H2BFWT as a susceptibility factor for male infertility, possibly with other genetic and environmental factors.
Lymphangiogenesis and cancer metastasis
Authors: Mumprecht Viviane , Detmar Michael
Published: July 2009

Anatomy and function of the lymphatic system

Tumour‐induced lymphangiogenesis promotes metastasis

Tumour‐induced lymph node lymphangiogenesis precedes cancer metastasis to lymph nodes

Tumour cell invasion into lymphatic vessels

Peri‐ and intra‐tumoral lymphangiogenesis

Lymphatic vessel markers and lymphangiogenic growth factors

Preventive and therapeutic potential of anti‐lymphangiogenic treatment

Tumour lymphangiogenesis as a prognostic indicator for lymph node metastasis

Diagnostic value of tumour‐associated lymphangiogenesis

Imaging of lymphatic vessels

Imaging lymphatic drainage

Non‐invasive imaging of lymph node metastases

Metastasis is a characteristic trait of most tumour types and the cause for the majority of cancer deaths. Many tumour types, including melanoma and breast and prostate cancers, first metastasize via lymphatic vessels to their regional lymph nodes. Although the connection between lymph node metastases and shorter survival times of patients was made decades ago, the active involvement of the lymphatic system in cancer, metastasis has been unravelled only recently, after molecular markers of lymphatic vessels were identified. A growing body of evidence indicates that tumour‐induced lymphangiogenesis is a predictive indicator of metastasis to lymph nodes and might also be a target for prevention of metastasis. This article reviews the current understanding of lymphangiogenesis in cancer anti‐lymphangiogenic strategies for prevention and therapy of metastatic disease, quantification of lymphangiogenesis for the prognosis and diagnosis of metastasis and in vivo imaging technologies for the assessment of lymphatic vessels, drainage and lymph nodes.
Hyperacetylation in prostate cancer induces cell cycle aberrations, chromatin reorganization and altered gene expression profiles
Authors: Watson Jenny A. , McKenna Declan J. , Maxwell Perry , Diamond James , Arthur Ken , McKelvey‐Martin Valerie J. , Hamilton Peter W
Published: July 2009

Histone acetylation is a fundamental mechanism in the regulation of local chromatin conformation and gene expression. Research has focused on the impact of altered epigenetic environments on the expression of specific genes and their pathways. However, changes in histone acetylation also have a global impact on the cell. In this study we used digital texture analysis to assess global chromatin patterns following treatment with trichostatin A (TSA) and have observed significant alterations in the condensation and distribution of higher‐order chromatin, which were associated with altered gene expression profiles in both immortalised normal PNT1A prostate cell line and androgen‐dependent prostate cancer cell line LNCaP. Furthermore, the extent of TSA‐induced disruption was both cell cycle and cell line dependent. This was illustrated by the identification of sub‐populations of prostate cancer cells expressing high levels of H3K9 acetylation in the G2/M phase of the cell cycle that were absent in normal cell populations. In addition, the analysis of enriched populations of G1 cells showed a global decondensation of chromatin exclusively in normal cells.
Physiological concentrations of bile acids down‐regulate agonist induced secretion in colonic epithelial cells
Authors: Keating Niamh , Mroz Magdalena S. , Scharl Michael M. , Marsh Christine , Ferguson Gail , Hofmann Alan F. , Keely Stephen J.
Published: July 2009

In patients with bile acid malabsorption, high concentrations of bile acids enter the colon and stimulate Cl− and fluid secretion, thereby causing diarrhoea. However, deoxycholic acid (DCA), the predominant colonic bile acid, is normally present at lower concentrations where its role in regulating transport is unclear. Thus, the current study set out to investigate the effects of physiologically relevant DCA concentrations on colonic epithelial secretory function. Cl− secretion was measured as changes in short‐circuit current across voltage‐clamped T84 cell monolayers. At high concentrations (0.5–1 mM), DCA acutely stimulated Cl− secretion but this effect was associated with cell injury, as evidenced by decreased transepithelial resistance (TER) and increased lactate dehydrogenase (LDH) release. In contrast, chronic (24 hrs) exposure to lower DCA concentrations (10–200 μM) inhibited responses to Ca2+ and cAMP‐dependent secretagogues without altering TER, LDH release, or secretagogue‐induced increases in intracellular second messengers. Other bile acids – taurodeoxycholic acid, chenodeoxycholic acid and cholic acid – had similar antisecretory effects. DCA (50 μM) rapidly stimulated phosphorylation of the epidermal growth factor receptor (EGFr) and both ERK and p38 MAPKs (mitogen‐activated protein kinases). The EGFr inhibitor, AG1478, and the protein synthesis inhibitor, cycloheximide, reversed the antisecretory effects of DCA, while the MAPK inhibitors, PD98059 and SB203580, did not. In summary, our studies suggest that, in contrast to its acute prosecretory effects at pathophysiological concentrations, lower, physiologically relevant, levels of DCA chronically down‐regulate colonic epithelial secretory function. On the basis of these data, we propose a novel role for bile acids as physiological regulators of colonic secretory capacity.
HDAC inhibitor, scriptaid, induces glioma cell apoptosis through JNK activation and inhibits telomerase activity
Authors: Sharma Vivek , Koul Nitin , Joseph Christy , Dixit Deobrat , Ghosh Sadashib , Sen Ellora
Published: July 2009

The present study identified a novel mechanism of induction of apoptosis in glioblastoma cells by scriptaid – a histone deacetylase (HDAC) inhibitor. Scriptaid reduced glioma cell viability by increasing Jun N‐terminal kinase (JNK) activation. Although scriptaid induced activation of both p38MAPK and JNK, it was the inhibition of JNK that attenuated scriptaid‐induced apoptosis significantly. Scriptaid also increased the expression of (i) p21 and p27 involved in cell‐cycle regulation and (ii) γH2AX associated with DNA damage response in a JNK‐dependent manner. Treatment with scriptaid increased Ras activity in glioma cells, and transfection of cells with constitutively active RasV12 further sensitized glioma cells to scriptaid‐induced apoptosis. Scriptaid also inhibited telomerase activity independent of JNK. Taken together, our findings indicate that scriptaid (i) induces apoptosis and reduces glioma cell proliferation by elevating JNK activation and (ii) also decreases telomerase activity in a JNK‐independent manner.
Unconventional implant treatment: I. Implant placement in contact with ankylosed root fragments. A series of five case reports
Authors: Davarpanah Mithridade , Szmukler‐Moncler Serge
Published: July 2009

Objective: Implant treatment presumes that implants are placed in bone, without any contact with root. At ankylosed teeth, complete root removal is often invasive; subsequently, the sites require additional augmentation procedures to complete the treatment. The aim of this paper is to report on a series of five cases that have been treated with an approach that avoided extractive invasive surgery and bone damage.

Material and methods: The procedure consisted of preparing the osteotomy site by drilling through the root. At the end of the drilling sequence, the root fragments that were not removed were deliberately left at the osteotomy site. Their mobility was checked with a dental pick and when stable an implant was placed in contact with them. The sites were required to be asymptomatic and inflammation free. Ankylosed teeth were replaced with 13–15‐mm‐long Osseotite implants, four in the anterior maxilla and one in the anterior mandible.

Results: All implants healed uneventfully; they have been now loaded for a period of 12–42 months. On peri‐apical radiographs, appearance of the bone–implant interface was similar to osseointegrated implants. The remaining root fragments were visible, in contact with the implants; no specific pathological sign could be detected. A limited resorption of dentine was found at one site after 4 years.

Conclusion: This series of cases suggests that implants placed in contact with ankylosed root fragments might not interfere with implant integration or harm occlusal function, at least in the mid‐term. More cases are warranted before this procedure might be considered as a reliable clinical option when, at ankylosed teeth, one wishes to avoid an invasive extraction surgery.
Influence of residual alveolar bone height on implant stability in the maxilla: an experimental animal study
Authors: Fenner Matthias , Vairaktaris Eleftherios , Stockmann Philipp , Schlegel Karl Andreas , Neukam Friedrich Wilhelm , Nkenke Emeka
Published: July 2009

Aims/Background: Empirically, for implant placement associated with sinus floor augmentation, a minimum of five mm of residual crestal bone height has been recommended in order to achieve sufficient initial implant stability. It has been the aim of the study to test this assumption in an experimental animal trial.

Material and methods: In eight mini pigs, three premolars and two molars were removed on one side of the maxilla. Three months later the animals were assigned to four groups of two animals each. A cavity was created at the base of the alveolar process so that the residual bone height was reduced to 2, 4, 6 and 8 mm, respectively. The coronal part of the alveolar crest remained unchanged. An inlay augmentation procedure was carried out using a particulated autogenous bone graft from the iliac crest, and six implants (Xive, diameter 3.8 mm, length 13 mm) were placed. Implant stability was assessed by resonance frequency analysis at the time of implant placement (T0), after 6 months of unloaded healing (T1) and after 6 months of functional loading (T2).

Results: During follow‐up, two implants were lost in sites with a residual alveolar bone height of 2 mm. At the time of implant placement, resonance frequencies were 6754.4±268, 6500.3±281.5, 6890.3±255.4 and 7877.9±233.7 Hz for residual bone heights of 2, 4, 6 and 8 mm, respectively. At stage‐two surgery and after 6 months of functional loading, resonance frequencies were 6431.7±290.8, 6351.8±437.6, 6213.4±376.2 and 6826.8±458.9 Hz vs. 6171±437.4, 6047±572.4, 6156.7±272.6 and 6412.8±283.5 Hz. Statistical analysis revealed an association of residual alveolar height and implant stability at T0 and T1 only (P<0.01), while bone height was not found to influence implant survival.

Conclusion: The results of the present trial demonstrate an association of alveolar bone height and implant stability at the time of implant placement and stage‐two surgery. Yet the assumption that 5 mm of residual crestal bone height is a relevant threshold for simultaneous implant placement and sinus floor augmentation is not supported from an experimental point of view.
Assessment of dental implant stability in osseodistraction‐generated bone: a resonance frequency analysis
Authors: Bilbao Arturo , Hernández‐De Oliveira M. , Varela‐Centelles Pablo I. , Seoane J.
Published: July 2009

Objective: To determine the implant stability in osseodistraction‐generated (ODG) bone after a 2‐month consolidation period, assessed by resonance frequency analysis (RFA).

Material and methods: Twenty healthy, non‐smoker female patients received 71 dental implants, 39 placed in native bone and 32 in ODG bone, after an 8‐week consolidation period. Primary and secondary stability of the implants was assessed by means of the Osstell®mentor device. The average value of six measurements was considered for the statistical analysis at each time point.

Results: The age of the patients who received implants in ODG was not significantly different from that of those receiving implants in pristine bone (48.0±10.9); [X=1.6; 95% confidence interval (CI)=−7.7–10.9].

Although implants placed in both bone types indicated good primary stability, a statistically significant difference in favour of implants placed in pristine bone could be identified in terms of osteogenic distraction (OD) (Xi−Xj=3.4; 95% CI=1.7–5.8). After a 1.5‐month integration period, none of the implants failed, but implant stability still recorded higher values for implants located in the pristine bone (Xi−Xj=2.5; 95% CI=0.5–4.4).

A positive linear correlation could be established between the implant stability quotient (ISQ) values at implant placement (primary stability) and the post‐integration ISQ score (secondary stability) for both bone types, but only 16% of the post‐integration ISQ in the ODG bone could be attributed to the primary stability.

Conclusions: Within the limitations of this study, OD bone offers – after a 2‐month consolidation period – high primary and secondary stabilities after implant placement.
Connective tissue graft plus resin‐modified glass ionomer restoration for the treatment of gingival recession associated with non‐carious cervical lesion: a randomized‐controlled clinical trial
Authors: Santamaria Mauro Pedrine , Ambrosano Gláucia Maria Bovi , Casati Marcio Zaffalon , Nociti Júnior Francisco Humberto , Sallum Antônio Wilson , Sallum Enilson Antônio
Published: July 2009

Background: The aim of this clinical study was to evaluate the treatment of gingival recession, associated with non‐carious cervical lesions by a connective tissue graft (CTG) alone, or in combination with a resin‐modified glass ionomer restoration (CTG+R).

Materials and Methods: Forty patients presenting Miller Class I buccal gingival recessions, associated with non‐carious cervical lesions, were selected. The defects were randomly assigned to receive either CTG or CTG+R. Bleeding on probing (BOP), probing depth (PD), relative gingival recession (RGR), clinical attachment level (CAL) and cervical lesion height (CLH) coverage were measured at baseline and 45 days, and 2, 3 and 6 months after treatment.

Results: Both groups showed statistically significant gains in CAL and soft tissue coverage. The differences between groups were not statistically significant in BOP, PD, RGR and CAL, after 6 months. The percentages of CLH covered were 74.88 ± 8.66% for CTG and 70.76 ± 9.81% for CTG+R (p>0.05). The estimated root coverage was 91.91 ± 17.76% for CTG and 88.64 ± 11.9% for CTG+R (p>0.05).

Conclusion: Within the limits of the present study, it can be concluded that both procedures provide comparable soft tissue coverage. The presence of the glass ionomer restoration may not prevent the root coverage achieved by CTG.
The effect of eye opening and closing on the result of facial wrinkle assessment
Authors: Tsukahara Kazue , Hotta Mitsuyuki , Osanai Osamu , Fujimura Tutomu , Kitahara Takashi , Takema Yoshinori
Published: July 2009

Background/purpose: Since there is no standard protocol that specifies the opening or closing of eyelids in wrinkle assessment, the eyelid position of subjects at the time of assessment varies from study to study. This study aimed to reveal the effect of eye opening and closing on the result of wrinkle assessment. The study also attempted to analyze the age‐, site‐, and ethnicity‐dependent variations in the effect.

Methods: Open‐ and closed‐eyed photographs were obtained from 87 Japanese women of ages ranging from 21 to 73 years, and also from 80 American women comprising of Asians, Caucasians, Africans and Hispanics in their 30s. Their wrinkle intensities were scored separately at nine facial sites using a five‐point photo scale. The obtained scores were compared between open‐ and closed‐eyed photographs. The differences were then compared across age‐ and ethnic‐groups.

Results: In Japanese subjects, a significant difference was found at the forehead wrinkle in all age groups, and also at the glabella, nasal root and eye corner in the middle and old age groups. In American subjects, significant differences were found at the forehead, nasal root, eye‐corner, and upper and lower eyelids. The differences were more prominent in the Hispanic and Caucasian Americans than in the Asian and African Americans.

Conclusion: These results suggest that the eyelid position should be considered as a variable in wrinkle assessment.
Transferrin‐Directed Internalization and Cycling of Transferrin Receptor 2
Authors: Chen Juxing , Wang Jinzhi , Meyers Kathrin R. , Enns Caroline A.
Published: July 2009

Transferrin receptor 2 (TfR2) is a homologue of transferrin receptor 1 (TfR1) but has distinct functions from TfR1 in iron homeostasis. In keeping with its proposed role in iron sensing, previous studies showed that TfR2 has a short half‐life and that holo‐Tf stabilizes TfR2 by redirecting it from a degradative pathway to a recycling pathway. In this study, we characterized how the endocytosis, recycling and degradation of TfR2 relates to its function and differs from TfR1. TfR2 endocytosis was adaptor protein‐2 (AP‐2) dependent. Flow cytometry analysis showed that TfR1 and TfR2 utilized the same endocytic pathway only in the presence of holo‐Tf, indicating that holo‐Tf alters the interaction of TfR2 with the endocytic machinery. Unlike TfR1, phosphofurin acidic cluster sorting protein 1 (PACS‐1) binds to the cytoplasmic domain of TfR2 and data suggest that PACS‐1 is involved in the TfR2 recycling. Depletion of TSG101 by siRNA or expression of a dominant negative Vps4 inhibited TfR2 degradation, indicating that TfR2 degradation occurs through a multivesicular body (MVB) pathway. TfR2 degradation is not mediated through ubiquitination on the single lysine (K31) in the cytoplasmic domain or on the amino terminal residue. No ubiquitination of TfR2 by HA‐ubiquitin was detected, indicating a lack of direct TfR2 ubiquitination involvement in its degradation.
A Comparative Analysis of Embryo and Endosperm Proteome from Seeds of Jatropha curcas
Authors: Liu Hui , Liu Yu‐Jun , Yang Ming‐Feng , Shen Shi‐Hua
Published: July 2009

Jatropha curcas is an important economic plant for biodiesel, which is extracted mainly from the endosperm of its mature seeds. Despite the morphological and functional differences between the embryo and endosperm, proteomic characteristics of the two tissues are not yet known. Similar proteomic profiles were observed in the two‐dimensional gel electrophoresis maps from the two tissues. There were 380 and 533 major protein spots in the embryo and endosperm, respectively. Fourteen identical spots, showing a notable change, were selected and identified by tandem mass spectrometry. Among these proteins, dihydrolipoamide acetyltransferase (spot 27) participates in tricarboxylic acid cycle, which is an amphibolic pathway. The two parts both included proteins related to stress (spots 8, 115, 118, 125, 130) and signal transduction (spots 7, 100, 108). According to the volume percentage of proteins in embryo and endosperm, the proteins in endosperm (spots 54, 61, 73) were catabolism‐related enzymes and reserves to provide the nutrition for seed germination; the proteins in embryo (spots 27, 62, 122) were inclined to anabolism and utilized the nutrition from the endosperm to generate a new life.
Sustainability Science Partnerships in Concept and in Practice: a Guide to a New Curriculum from a European Perspective
Authors: DE LA VEGA‐LEINERT A. CRISTINA , STOLL‐KLEEMANN SUSANNE , O'RIORDAN TIM
Published: July 2009

This paper makes the case for advancing sustainability science partnerships (SSPs) both within universities and through innovative means of integrating universities with external public‐private and civil sectors. It links the basic principles of sustainable development with an emerging science of cooperative learning that connects researchers to a wide range of partners. SSPs are specifically designed to be transformational through becoming active agents for societal change. Universities play a special role here because they can act both as communication networks and as laboratories for developing the capability to design and manage SSPs in the creative transition to sustainability. It is gratifying to note that these ideas are beginning to emerge in a number of universities, with European examples being highlighted in this paper. Further steps towards introducing full‐blooded SSPs across the university spectrum are suggested.
Enhanced pulmonary expression of the TrkB neurotrophin receptor in hypoxic rats is associated with increased acetylcholine‐induced airway contractility
Authors: Sciesielski L. K. , Paliege A. , Martinka P. , Scholz H.
Published: July 2009

Aim:  We have recently reported that hypoxia stimulates transcription of the TrkB neurotrophin receptor in cultured cells via stabilization of hypoxia‐inducible factor‐1α. Here we investigated whether the expression of TrkB and other neurotrophin receptors is oxygen‐sensitive also in vivo, and explored the functional consequences of an oxygen‐regulated TrkB expression.

Methods:  Rats were exposed either to 21% O2 or 8% O2 for 6 h and TrkB was analysed by reverse transcription real‐time PCR, in situ mRNA hybridization, and immunological techniques. The importance of the brain‐derived neurotrophic factor (BDNF)‐TrkB pathway in the control of mechanical airway function was assessed on isolated tracheal segments from normoxic and hypoxic rats.

Results:  TrkB transcripts were increased approx. 15‐fold in the lungs of hypoxic rats, and the respiratory epithelium was identified as the site of enhanced TrkB expression in hypoxia. The TrkB ligand, BDNF, significantly increased the contractile response to acetylcholine (ACh) of isolated tracheal segments from hypoxic but not from normoxic rats. This effect of BDNF was prevented by pre‐incubation of the tissue specimens with the tyrosine kinase inhibitor K252a and by mechanical removal of the TrkB containing airway epithelium. Likewise, the nitric oxide (NO) synthase inhibitor l‐NAME abrogated the influence of BDNF on ACh‐induced contractions of isolated tracheal segments from hypoxic rats.

Conclusion:  These results demonstrate that systemic hypoxia stimulates expression of the TrkB neurotrophin receptor in the airway epithelium. Furthermore, activation of TrkB signalling by BDNF in hypoxia enhances mechanical airway contractility to ACh through a mechanism that requires NO.
Sodium–calcium exchangers contribute to the regulation of cytosolic calcium levels in mouse taste cells
Authors: Laskowski Agnieszka I. , Medler Kathryn F.
Published: July 2009

Taste cells use multiple signalling mechanisms to generate unique calcium responses to distinct taste stimuli. Some taste stimuli activate G‐protein coupled receptors (GPCRs) that cause calcium release from intracellular stores while other stimuli depolarize taste cells to cause calcium influx through voltage‐gated calcium channels (VGCCs). We recently demonstrated that a constitutive calcium influx exists in taste cells that is regulated by mitochondrial calcium transport and that the magnitude of this calcium influx correlates with the signalling mechanisms used by the taste cells. In this study, we used calcium imaging to determine that sodium–calcium exchangers (NCXs) also routinely contribute to the regulation of basal cytosolic calcium and that their relative role correlates with the signalling mechanisms used by the taste cells. RT‐PCR analysis revealed that multiple NCXs and sodium–calcium–potassium exchangers (NCKXs) are expressed in taste cells. Thus, a dynamic relationship exists between calcium leak channels and calcium regulatory mechanisms in taste cells that functions to keep cytosolic calcium levels in the appropriate range for cell function.
Filling of Partially Collapsed Compliant Tubes
Authors: Jan D. L. , Kamm R. D. , Shapiro A. H.
Published: July 2009

Filling of a thin-walled, highly compliant tube in a partially collapsed condition is studied. The theory, based on one-dimensional flow, takes account of friction, longitudinal tension, and the highly nonlinear pressure-area law for the tube. Various aspects of filling behavior are revealed by alternative calculations using: (i) the method of characteristics; (ii) numerical integration of the continuity, momentum, and tube-law equations; and (iii) a crude but simple lumped-element capacitance-inertance-resistance model. Varied phenomena appear. At high Reynolds number, these include dispersive wave trains associated with circumferential bending stiffness and longitudinal tension, nonlinear changes of wave form, development of highly asymmetrical wave reflections, and sloshing. At low Reynolds number, the area changes with time in a diffusivelike manner. The experiments exhibited the dispersive phenomena predicted by the theory.
Effect of Timing and Velocity of Impact on Ventricular Myocardial Rupture
Authors: Lau Ian V.
Published: July 2009

The effects of impact timing during the cardiac cycle on the sensitivity of the heart to impact-induced rupture was investigated in an open-chest animal model. Direct mechanical impacts were applied to two adjacent sites on the exposed left ventricular surface at the end of systole or diastole. Impacts at 5 m/s and a contact stroke of 5 cm at the end of systole resulted in no cardiac rupture in seven animals, whereas similar impacts at the end of diastole resulted in six cardiac ruptures. Direct impact at 15 m/s and a contact stroke of 2 cm at the end of either systole or diastole resulted in perforationlike cardiac rupture in all attempts. At low-impact velocity the heart was observed in high-speed movie to bounce away from the impact interface during a systolic impact, but deform around the impactor during a diastolic impact. The heart generally remained motionless during the downward impact stroke at high-impact velocity in either a systolic or diastolic impact. The lower ventricular pressure, reduced muscle stiffness, thinner myocardial wall and larger mass of the filled ventricle probably contributed to a greater sensitivity of the heart to rupture in diastole at low-impact velocity. However, the same factors had no role at high-impact velocity.
Soft Tissue Attenuation of Acoustic Emission Pulses
Authors: Wright T. M. , Carr J. M.
Published: July 2009

The soft tissue attenuation of acoustic emission signals was measured by transmitting pulses through volunteers and measuring the decay of the waveform characteristics of the pulse as a function of the thickness of the interposed tissue. Waveform characteristics of the received signal (signal duration, number of counts, peak amplitude, energy, and rise time) demonstrated an exponential decrease with increasing tissue thickness. The decrease appeared insensitive to the frequency of the pulse within the range of 50 to 600 KHz.
Heat and Water Vapor Transport in the Human Upper Airways at Hyperbaric Conditions
Authors: Nuckols M. L. , Zumrick J. L. , Johnson C. E.
Published: July 2009

Heat and mass transfer mechanisms have been characterized in physical models of human cadaver airways to simulated depths of 305 m with various gas mixtures. Such characterizations offer a detailed understanding of the effects of environmental pressures, gas composition, and respiratory rates (RMV) on the body cooling capacity of the respiratory airways. Empirical heat transfer relationships in the form Nu¯=AReNPr1/3 are derived for the oral and nasal passageways during inhalation and exhalation flows. N¯u, Re, and Pr are the dimensionless Nusselt, Reynolds, and Prandtl numbers, respectively. The Nusselt and Reynolds numbers are based on the diameter and gas flow rate in the trachea and are applicable to Reynolds number values up to 70,000.