bluuebunny/crossref_metadata_2025 huggingface dataset:
Apligraf in the Treatment of Neuropathic Diabetic Foot Ulcers
Authors: Edmonds Michael ,   European and Australian Apligraf Diabetic Foot Ulcer Study Group
Published: February 2009

This study compared the efficacy and safety of Apligraf (Organogenesis, Inc., Canton, MA) in combination with standard therapy versus standard therapy alone in the treatment of neuropathic diabetic foot ulcers. Efficacy was assessed by time to complete wound healing (by 12 weeks) and incidence of complete wound closure (at 12 weeks). This was an international multi-center, randomized, controlled study. Patients were eligible for entry into the study if the following criteria were met: type 1 or type 2 diabetes mellitus, age 18 to 80 years, adequate glycemic control, and the presence of a full-thickness neuropathic ulcer for at least 2 weeks prior to the initial screening visit. Following the 2-week screening period, the 2 treatment groups received standard ulcer care consistent with international treatment guidelines that comprised sharp debridement, saline-moistened dressings, and a non—weight bearing regimen. There were 106 subjects screened for enrollment, 82 randomized to the treatment groups, and 72 treated (33 Apligraf subjects and 39 standard therapy subjects) before the study was terminated. Kaplan—Meier curves indicated a trend for shorter time to complete wound healing in the Apligraf group compared with the standard therapy group ( p = .059; log-rank test). The median time to healing was 84 days in the Apligraf group, whereas no median time to healing could be determined for the standard therapy group because <50% of the standard therapy subjects healed. By 12 weeks, 51.5% (17/33) Apligraf subjects had achieved complete wound closure compared with 26.3% (10/38) of standard therapy subjects ( p = .049; Fisher's exact test). Even though the study was halted prematurely, this study suggested that the use of Apligraf resulted in a higher incidence of wound closure by 12 weeks.
Case Study: Chronic Femoropopliteal Prosthetic Graft Infection With Exposed Graft
Authors: McCready Robert A. , Bryant M. Ann , Divelbiss Janet , Wack Matthew F. , Mattison H. Reid
Published: February 2009

One of the most feared complications following vascular reconstruction is infection due to the attendant risks of limb loss, sepsis, or death. The reported incidence of infection following infrainguinal prosthetic graft infection is 2.5% with associated mortality rates and amputation rates of 18% and 41%, respectively. There are several options in treating infected prosthetic infrainguinal bypass grafts. Some authors have advocated complete removal of the infected graft with concomitant in situ revascularization using autogenous tissue or extra-anatomic bypass using either autogenous or prosthetic material, depending upon the clinical circumstances. Other authors have advocated attempting graft preservation to decrease the risk of amputation. Infected, thrombosed grafts are generally treated with graft excision alone with care taken to preserve collateral flow. The treatment options may also be influenced by the type of infection, as infections caused by gram-negative bacteria are thought to be more virulent than those associated with gram-positive bacteria. We recently treated a patient with an 18-month history of an exposed prosthetic graft in the groin, which was infected by Proteus mirabilis. Despite the extended period of graft exposure and despite gram-negative bacteria being the causative organism, the patient reported only intermittent drainage of pus from the groin. The management of this unusual infection forms the basis of this report.
Ischemia-reperfusion Injury in the Lung: Quantitation Using Electron Microscopy
Authors: Hasaniya Nahidh W. , Premaratne Shyamal , Zhang Wayne W. , Razzuk Aziz M. , Abdul-Ghani Ayman A. , Siera Milea , Dashwood Roderick H. , Eklof Bo , Tinsley Larry R. , McNamara J. Judson
Published: February 2009

Background: The primary objectives of this study were to determine the time course of ischemia-reperfusion injury in an isolated rabbit lung model and to quantify this damage using electron microscopic methodology coupled with statistical analyses. Materials and Methods: Eight groups of isolated rabbit lungs (n = 5 per group) were subjected to predetermined periods of ischemia-reperfusion. Two hours of ischemia and 4 hours of reperfusion were concluded to be necessary to induce optimal ischemia-reperfusion injury in this model. Four other groups were subjected to 2 hours of ischemia followed by selected periods of reperfusion. These groups were compared to 4 control groups that were perfused for comparable time periods but without the initial ischemia. New quantitative methods were developed based on the average surface area of the alveoli and average number of alveoli per unit surface area, using scanning electron microscopic examination. Results: Ischemia per se caused substantial damage. Restoration of volume and nutrients reversed this damage at 1 hour of reperfusion, but severe damage was evident at 4 hours of reperfusion, as reported by subjective and blinded examination. By using the new quantitative methods, there was a significant difference between the groups (P < .005) according to the time of post—ischemia-reperfusion, which correlated with the subjective evaluation of damage. Conclusions: These 2 new quantitative techniques provide an objective assessment of damage in the isolated rabbit lung model, suggesting that they warrant further consideration in similar studies of ischemia reperfusion injury.
How Optimal is the Medical Management of Patients Prior to Major Reconstructive Vascular Surgery? The Results of a Cross-sectional Study
Authors: Marshall Christy , Lin Peter H. , Huynh Tam T. , Kougias Panagiotis
Published: February 2009

Background: Risk factor modification is important in patients with vascular disease. Guidelines suggest that this patient population benefits from a medical regimen of antiplatelets, statins, β-blockers, and angiotensin-converting enzyme (ACE) inhibitors. Materials and Methods: The medical regimen of consecutive patients who presented for major vascular surgery intervention over 18 months was examined. Results: Of the 325 patients identified, 176 (54%) were on antiplatelet treatment, 197 (61%) were on a statin, 180 (55%) on β-blockers, and 146 (54%) on ACE inhibitors. A high-risk subset of 94 smokers with known coronary artery disease, hypertension, and hyperlipidemia or diabetes was identified. In this subset, patients were more likely to be on pharmacologic risk factor modification. Conclusions: Despite recommendations, the pharmacologic risk factor modification of patients prior to vascular surgery remains suboptimal. Increased awareness of the problem and active participation of the vascular specialist are essential to improve compliance with established guidelines.
Retroperitoneal Repair of Abdominal Aortic Aneurysm Reduces Bowel Dysfunction
Authors: Arya Nityanand , Muhammad Anees Sharif  , Lau Luk Louis , Lee Bernard , Hannon Raymond J. , Young Ian S. , Chee Voon Soong
Published: February 2009

Objective: To assess the effect of intestinal manipulation and mesenteric traction on gastro-intestinal function and postoperative recovery in patients undergoing abdominal aortic aneurysm (AAA) repair. Methods: Thirty-five patients undergoing AAA repair were randomised into 3 groups. Group I (n = 11) had repair via retroperitoneal approach while Group II (n = 12) and Group III (n = 12) were repaired via transperitoneal approach with bowel packed within the peritoneal cavity or exteriorised in a bowel bag respectively. Gastric emptying was measured pre-operatively (day 0), day 1 and day 3 using paracetamol absorption test (PAT) and area under curve (PAUC) was calculated. Intestinal permeability was measured using the Lactulose-Mannitol test. Results: Aneurysm size, operation time and PAT (on day 0 and day 3) were similar in the three groups. On day 1, the PAUC was significantly higher in Group I, when compared with Group II and Group III (P = .02). Resumption of diet was also significantly earlier in Group I as compared to Group II and Group III. The intestinal permeability was significantly increased in Group II and Group III at day 1 when compared with day 0, with no significant increase in Group I. Retroperitoneal repair was also associated with significantly shorter intensive care unit (P = .04) and hospital stay (P = .047), when compared with the combined transperitoneal repair group (Group II and III). Conclusion: Retroperitoneal AAA repair minimises intestinal dysfunction and may lead to quicker patient recovery when compared to transperitoneal repair.
Feasibility of Iterative Learning Control Mediated by Functional Electrical Stimulation for Reaching After Stroke
Authors: Hughes A.M. , Freeman C.T. , Burridge J.H. , Chappell P.H. , Lewin P.L. , Rogers E.
Published: February 2009

Background. An inability to perform tasks involving reaching is a common problem following stroke. Evidence supports the use of robotic therapy and functional electrical stimulation (FES) to reduce upper limb impairments, but current systems may not encourage maximal voluntary contribution from the participant because assistance is not responsive to performance. Objective. This study aimed to investigate whether iterative learning control (ILC) mediated by FES is a feasible intervention in upper limb stroke rehabilitation. Methods. Five hemiparetic participants with reduced upper limb function who were at least 6 months poststroke were recruited from the community. No participants withdrew. Intervention. Participants undertook supported tracking tasks using 27 different trajectories augmented by responsive FES to their triceps brachii muscle, with their hand movement constrained in a 2-dimensional plane by a robot. Eighteen 1-hour treatment sessions were used with 2 participants receiving an additional 7 treatment sessions. Outcome measures. The primary functional outcome measure was the Action Research Arm Test (ARAT). Impairment measures included the upper limb Fugl— Meyer Assessment (FMA), tests of motor control (tracking accuracy), and isometric force. Results. Compliance was excellent and there were no adverse events. Statistically significant improvements were measured ( P ≤ .05) in FMA motor score, unassisted tracking for 3 out of 4 trajectories, and in isometric force over 5 out of 6 directions. Changes in ARAT were not statistically significant. Conclusion. This study has demonstrated the feasibility of using ILC mediated by FES for upper limb stroke rehabilitation.
Influence of Gravity Compensation on Muscle Activation Patterns During Different Temporal Phases of Arm Movements of Stroke Patients
Authors: Prange G.B. , Jannink M.J.A. , Stienen A.H.A. , van der Kooij H. , IJzerman M.J. , Hermens H.J.
Published: February 2009

Background. Arm support to help compensate for the effects of gravity may improve functional use of the shoulder and elbow during therapy after stroke, but gravity compensation may alter motor control. Objective. To obtain quantitative information on how gravity compensation influences muscle activation patterns during functional, 3-dimensional reaching movements. Methods. Eight patients with mild hemiparesis performed 2 sets of repeated reach and retrieval movements, with and without unloading the arm, using a device that acted at the elbow and forearm to compensate for gravity. Electromyographic (EMG) patterns of 6 upper extremity muscles were compared during elbow and shoulder joint excursions with and without gravity compensation. Results. Movement performance was similar with and without gravity compensation. Smooth rectified EMG (SRE) values were decreased from 25% to 50% during movements with gravity compensation in 5 out of 6 muscles. The variation of SRE values across movement phases did not differ across conditions. Conclusions. Gravity compensation did not affect general patterns of muscle activation in this sample of stroke patients, probably since they had adequate function to complete the task without arm support. Gravity compensation did facilitate active arm movement excursions without impairing motor control. Gravity compensation may be a valuable modality in conventional or robot-aided therapy to increase the intensity of training for mildly impaired patients.
A Techno-Semiotic Approach to Cheating in Computer Games
Authors: Kücklich Julian
Published: February 2009

This article is an attempt to understand cheating in digital games as a practice that highlights the machinicity of the process of digital gameplay. The significance of this endeavor lies in the fact that digital gameplay is often naturalized—by the digital games industry, by players, and by scholars in the burgeoning field of digital game studies—which leads to an obfuscation of the inherently cybernetic character of videogames. Cheating and other ``de-ludic'' practices can counteract this naturalization and reveal the process of ``becoming-machine'' that lies at the heart of digital gameplay.
Managing Erectile Dysfunction in Patients With Cardiovascular Diseases: The Efficacy and Safety of Phosphodiesterase-5 Inhibitors
Authors: Cheng Judy W. M. , Berhane Selamawit R.
Published: February 2009

Patients with cardiovascular disease have a high prevalence of erectile dysfunction. Recent evidence demonstrated that erectile dysfunction is an early indication of coronary artery disease. Phosphodiesterase-5 (PDE-5) inhibitors are effective in managing erectile dysfunction due to cardiovascular disease. However, when used together with nitrates or other vasodilators such as alpha-antagonists, they may cause hypotension. Clinical studies demonstrated that in patients with stable coronary artery disease, heart failure, and hypertension controlled by medications who were not receiving nitrates, PDE-5 inhibitors were well tolerated. Therefore, it is important for clinicians to carefully evaluate each patient before initiating PDE-5 inhibitors. PDE-5 inhibitors are absolutely contraindicated with concurrent nitrate use. No PDE-5 inhibitors should be administered within 12 hours after the last nitrate dose. If a patient develops chest pain while taking PDE-5 inhibitors, nitrates should be administered only after the PDE-5 inhibitors have been washed out of the system, based on the half-life of individual agents (washed-out period for sildenafil ∽20 hours; vardenafil ∽ 24 hours; tadalafil ∽88 hours [or 3-4 days]). If symptomatic hypotension occurs, patients should be put in a Trendelenburg position. Fluid resuscitation therapy and alpha-agonists should be used to support blood pressure, if necessary. PDE-5 inhibitors have not been studied in patients with severe and unstable cardiac conditions.
Green tea polyphenols block the anticancer effects of bortezomib and other boronic acid–based proteasome inhibitors
Authors: Golden Encouse B. , Lam Philip Y. , Kardosh Adel , Gaffney Kevin J. , Cadenas Enrique , Louie Stan G. , Petasis Nicos A. , Chen Thomas C. , Schönthal Axel H.
Published: February 2009

The anticancer potency of green tea and its individual components is being intensely investigated, and some cancer patients already self-medicate with this “miracle herb” in hopes of augmenting the anticancer outcome of their chemotherapy. Bortezomib (BZM) is a proteasome inhibitor in clinical use for multiple myeloma. Here, we investigated whether the combination of these compounds would yield increased antitumor efficacy in multiple myeloma and glioblastoma cell lines in vitro and in vivo. Unexpectedly, we discovered that various green tea constituents, in particular (-)-epigallocatechin gallate (EGCG) and other polyphenols with 1,2-benzenediol moieties, effectively prevented tumor cell death induced by BZM in vitro and in vivo. This pronounced antagonistic function of EGCG was evident only with boronic acid–based proteasome inhibitors (BZM, MG-262, PS-IX), but not with several non–boronic acid proteasome inhibitors (MG-132, PS-I, nelfinavir). EGCG directly reacted with BZM and blocked its proteasome inhibitory function; as a consequence, BZM could not trigger endoplasmic reticulum stress or caspase-7 activation, and did not induce tumor cell death. Taken together, our results indicate that green tea polyphenols may have the potential to negate the therapeutic efficacy of BZM and suggest that consumption of green tea products may be contraindicated during cancer therapy with BZM.
Bortezomib induces osteoblast differentiation via Wnt-independent activation of β-catenin/TCF signaling
Authors: Qiang Ya-Wei , Hu Bo , Chen Yu , Zhong Ying , Shi Bingyin , Barlogie Bart , Shaughnessy John D.
Published: February 2009

Inhibition of Wnt/β-catenin/T-cell factor (TCF) signaling induces proliferation of mesenchymal stem cells and/or suppresses their differentiation into osteoblasts (OBs). Osteolysis in multiple myeloma (MM) is related to the suppression of canonical Wnt signaling caused by DKK1, a soluble inhibitor of this pathway secreted by MM cells. Bortezomib (Bzb) can induce OB differentiation in vitro and in vivo and its anti-MM efficacy linked to bone anabolic effects. However, the molecular basis of the action of Bzb on bone is not completely understood. In the present study, we show that Bzb promotes matrix mineralization and calcium deposition by osteoprogenitor cells and primary mesenchymal stem cells via Wnt-independent activation of β-catenin/TCF signaling. Using affinity pull-down assays with immunoblotting and immunofluorescence, we found that Bzb induced stabilization of β-catenin. Nuclear translocation of stabilized β-catenin was associated with β-catenin/TCF transcriptional activity that was independent of the effects of Wnt ligand-receptor-induced signaling or GSK3β activation. Blocking the activation of β-catenin/TCF signaling by dominant negative TCF attenuated Bzb-induced matrix mineralization. These results provide evidence that Bzb induces OB differentiation via Wnt-independent activation of β-catenin/TCF pathway and suggest that proteasome inhibition therapy in MM may function in part by subverting tumor-induced suppression of canonical Wnt signaling in the bone microenvironment.
Rev and Rex proteins of human complex retroviruses function with the MMTV Rem-responsive element
Authors: Mertz Jennifer A , Lozano Mary M , Dudley Jaquelin P
Published: February 2009

Background

Mouse mammary tumor virus (MMTV) encodes the Rem protein, an HIV Rev-like protein that enhances nuclear export of unspliced viral RNA in rodent cells. We have shown that Rem is expressed from a doubly spliced RNA, typical of complex retroviruses. Several recent reports indicate that MMTV can infect human cells, suggesting that MMTV might interact with human retroviruses, such as human immunodeficiency virus (HIV), human T-cell leukemia virus (HTLV), and human endogenous retrovirus type K (HERV-K). In this report, we test whether the export/regulatory proteins of human complex retroviruses will increase expression from vectors containing the Rem-responsive element (RmRE).

Results

MMTV Rem, HIV Rev, and HTLV Rex proteins, but not HERV-K Rec, enhanced expression from an MMTV-based reporter plasmid in human T cells, and this activity was dependent on the RmRE. No RmRE-dependent reporter gene expression was detectable using Rev, Rex, or Rec in HC11 mouse mammary cells. Cell fractionation and RNA quantitation experiments suggested that the regulatory proteins did not affect RNA stability or nuclear export in the MMTV reporter system. Rem had no demonstrable activity on export elements from HIV, HTLV, or HERV-K. Similar to the Rem-specific activity in rodent cells, the RmRE-dependent functions of Rem, Rev, or Rex in human cells were inhibited by a dominant-negative truncated nucleoporin that acts in the Crm1 pathway of RNA and protein export.

Conclusion

These data argue that many retroviral regulatory proteins recognize similar complex RNA structures, which may depend on the presence of cell-type specific proteins. Retroviral protein activity on the RmRE appears to affect a post-export function of the reporter RNA. Our results provide additional evidence that MMTV is a complex retrovirus with the potential for viral interactions in human cells.
HIV-1 exploits importin 7 to maximize nuclear import of its DNA genome
Authors: Zaitseva Lyubov , Cherepanov Peter , Leyens Lada , Wilson Sam J , Rasaiyaah Jane , Fassati Ariberto
Published: February 2009

Background

Nuclear import of the HIV-1 reverse transcription complex (RTC) is critical for infection of non dividing cells, and importin 7 (imp7) has been implicated in this process. To further characterize the function of imp7 in HIV-1 replication we generated cell lines stably depleted for imp7 and used them in conjunction with infection, cellular fractionation and pull-down assays.

Results

Imp7 depletion impaired HIV-1 infection but did not significantly affect HIV-2, simian immunodeficiency virus (SIVmac), or equine infectious anemia virus (EIAV). The lentiviral dependence on imp7 closely correlated with binding of the respective integrase proteins to imp7. HIV-1 RTC associated with nuclei of infected cells with remarkable speed and knock down of imp7 reduced HIV-1 DNA nuclear accumulation, delaying infection. Using an HIV-1 mutant deficient for reverse transcription, we found that viral RNA accumulated within nuclei of infected cells, indicating that reverse transcription is not absolutely required for nuclear import. Depletion of imp7 impacted on HIV-1 DNA but not RNA nuclear import and also inhibited DNA transfection efficiency.

Conclusion

Although imp7 may not be essential for HIV-1 infection, our results suggest that imp7 facilitates nuclear trafficking of DNA and that HIV-1 exploits imp7 to maximize nuclear import of its DNA genome. Lentiviruses other than HIV-1 may have evolved to use alternative nuclear import receptors to the same end.
HIV-1 transgene expression in rats causes oxidant stress and alveolar epithelial barrier dysfunction
Authors: Lassiter Coy , Fan Xian , Joshi Pratibha C , Jacob Barbara A , Sutliff Roy L , Jones Dean P , Koval Michael , Guidot David M
Published: February 2009

Background

HIV-infected individuals are at increased risk for acute and chronic airway disease even though there is no evidence that the virus can infect the lung epithelium. Although HIV-related proteins including gp120 and Tat can directly cause oxidant stress and cellular dysfunction, their effects in the lung are unknown. The goal of this study was to determine the effects of HIV-1 transgene expression in rats on alveolar epithelial barrier function. Alveolar epithelial barrier function was assessed by determining lung liquid clearance in vivo and alveolar epithelial monolayer permeability in vitro. Oxidant stress in the alveolar space was determined by measuring the glutathione redox couple by high performance liquid chromatography, and the expression and membrane localization of key tight junction proteins were assessed. Finally, the direct effects of the HIV-related proteins gp120 and Tat on alveolar epithelial barrier formation and tight junction protein expression were determined.

Results

HIV-1 transgene expression caused oxidant stress within the alveolar space and impaired epithelial barrier function even though there was no evidence of overt inflammation within the airways. The expression and membrane localization of the tight junction proteins zonula occludens-1 and occludin were decreased in alveolar epithelial cells from HIV-1 transgenic rats. Further, treating alveolar epithelial monolayers from wild type rats in vitro with recombinant gp120 or Tat for 24 hours reproduced many of the effects on zonula occludens-1 and occludin expression and membrane localization.

Conclusion

Taken together, these data indicate that HIV-related proteins cause oxidant stress and alter the expression of critical tight junction proteins in the alveolar epithelium, resulting in barrier dysfunction.
Petrophysical seismic inversion conditioned to well-log data: Methods and application to a gas reservoir
Authors: Bosch Miguel , Carvajal Carla , Rodrigues Juan , Torres Astrid , Aldana Milagrosa , Sierra Jesús
Published: February 2009

Hydrocarbon reservoirs are characterized by seismic, well-log, and petrophysical information, which is dissimilar in spatial distribution, scale, and relationship to reservoir properties. We combine this diverse information in a unified inverse-problem formulation using a multiproperty, multiscale model, linking properties statistically by petrophysical relationships and conditioning them to well-log data. Two approaches help us: (1) Markov-chain Monte Carlo sampling, which generates many reservoir realizations for estimating medium properties and posterior marginal probabilities, and (2) optimization with a least-squares iterative technique to obtain the most probable model configuration. Our petrophysical model, applied to near-vertical-anglestackedseismic data and well-log data from a gas reservoir, includes a deterministic component, based on a combination of Wyllie and Wood relationships calibrated with the well-log data, and a random component, based on the statistical characterization of the deviations of well-log data from the petrophysical transform. At the petrophysical level, the effects of porosity and saturation on acoustic impedance are coupled; conditioning the inversion to well-log data helps resolve this ambiguity. The combination of well logs, petrophysics, and seismic inversion builds on the corresponding strengths of each type of information, jointly improving (1) cross resolution of reservoir properties, (2) vertical resolution of property fields, (3) compliance to the smooth trend of property fields, and (4) agreement with well-log data at well positions.
Time-lapse image registration using the local similarity attribute
Authors: Fomel Sergey , Jin Long
Published: February 2009

We present a method to register time-lapse seismic images based on the local-similarity attribute. We define registration as an automatic point-by-point alignment of time-lapse images. Stretching and squeezing a monitor image and computing its local similarity to the base image allows us to detect an optimal registration even in the presence of significant velocity changes in the overburden. A by-product of this process is an estimate of the ratio of the interval seismic velocities in the reservoir interval. We illustrate the proposed method and demonstrate its effectiveness using both synthetic experiments and real data from a time-lapse experiment in the Duri field, Indonesia.
Euthyroid Hyperthyrotropinemia in Children Born after in Vitro Fertilization
Authors: Sakka Sophia D. , Malamitsi-Puchner Ariadne , Loutradis Dimitrios , Chrousos George P. , Kanaka-Gantenbein Christina
Published: February 2009

Context: Assisted reproduction techniques are now commonly used. Although classic in vitro fertilization (IVF) started almost 30 yr ago, few long-term systematic prospective studies of children conceived with assisted reproduction have been performed.

Objective: Our objective was to investigate thyroid function in children conceived after IVF vs. naturally conceived controls.

Populations and Methods: A total of 106 children conceived after classic IVF and 68 naturally conceived controls, aged 4–14 yr, were studied. All children were thoroughly examined, and serum T3, T4, TSH, anti-thyroid peroxidase, and anti-thyroglobulin antibodies were measured. A second TSH determination and a thyroid ultrasound were performed for TSH higher than 5 μIU/ml, and children were considered to have persistent hyperthyrotropinemia, if the TSH elevation was confirmed.

Results: Seven IVF children but none of the controls had persistent elevations of circulating TSH, suggesting euthyroid hyperthyrotropinemia or subclinical primary hypothyroidism (P = 0.044). TSH was significantly higher in the IVF group than in controls (P = 0.046), whereas no significant differences in the concentrations of T3 or T4 were observed. None of the children had detectable circulating antithyroid antibodies in either group.

Conclusions: A significant elevation of serum TSH compatible with a mild TSH resistance of the thyroid were found in IVF children compared with controls. This was not due to the presence of antithyroid autoantibodies. We suggest that this might represent a slight epigenetic developmental abnormality related to the preimplantation manipulation of the embryo. Further studies are needed to confirm these findings and to better determine their etiopathogenesis and clinical significance.
Harmonic Cross-Reference and the Dialectic of Articulation and Continuity in Sonata Expositions of Schubert and Brahms
Authors: Smith Peter H.
Published: February 2009

Associative harmony functions as a powerful resource through which Schubert and Brahms fashion continuities within the dialectic of articulation and continuity that stands at the heart of the Viennese sonata style. More specifically, the technique of harmonic cross-reference provides these composers with one among a number of integrative strategies to counterbalance the threat of self-contained lyricism in the middle sections of their tripartite expositions. In one type of expositional context, this integration involves harmonic linkage designed specifically to efface a formal boundary. In a second type, it involves a more general sense of continuity between formal sections.

The study of harmonic cross-reference in the three-key expositions of Schubert's Quartettsatz and String Quintet and Brahms's Second Symphony and Clarinet Trio reveals a tension between functional distinctions for the sonorities involved (as defined by Schenkerian analysis), and the interconnection of these sonorities in processes of motivic development. Through this motivic interconnection, the sonorities achieve an ontological status partially independent of their individual linear-contrapuntal environments. Each motivic harmony gains meaning through its particular tonal function, but each also exists within a network of associative connection based more generally on chord identity.
From Dispersed to Distributed Archives: The Past and the Present of Samizdat Material
Authors: Zaslavskaya Olga
Published: February 2009

Historians turn to archives for historical evidence, the availability of which is not to be taken for granted. In many cases, archival practice excludes a significant part of documentation from archival solicitation.1 This can be applied to the history of the samizdat documents, which were excluded from the long-term preservation policy of state archival authorities in the Soviet bloc countries. At the same time, the singularity of the historical context that had motivated the emergence and spread of samizdat also engendered the peculiar logic of its circulation. A significant share of samizdat documents were smuggled out of the communist countries to the West, ending up in numerous organizations and private collections abroad. The dispersed character of samizdat archival sources has a negative effect on the quality of research in this area. One of the main objectives of the International Samizdat [Research] Association is to find and work out possible solutions to overcome the decay of samizdat materials both physically and “virtually”—in the collective memory of the present and for the cultural memory of future generations.
Samizdat and the Problem of Authorial Control: The Case of Varlam Shalamov
Authors: Toker Leona
Published: February 2009

The article offers an explanation of Varlam Shalamov's negative attitude to the samizdat in the 1970s, particularly puzzling in view of the samizdat's role in making him unofficially famous in the 1960s. It explains the change in Shalamov's views by his struggle for authorial control of the accuracy, structure, and accessibility of his work. Lack of such control was, in a sense, an extension of the Gulag prisoners' inability, despite their best-laid plans, to rule their own fate—a theme explored in Shalamov's story “A Piece of Meat.” One of Shalamov's last acts in the struggle for the control of the fate of his works was his 1972 letter to Literaturnaia gazeta protesting against the piecemeal publication of his work in foreign journals. Contemporaries tended to read that document as a recantation letter renouncing Kolyma Tales; as a result, Shalamov's status was transformed into that of a fallen idol. Yet if one reads the letter with close attention to its composite language, in which current clichés combine with the lexis of the twenties, as well as in the context of Shalamov's predicament in the 1970s (when a work that had appeared in the samizdat had practically no chance of getting into the official press), one may see a message about the importance of Kolyma Tales hidden in plain view. Ultimately, however, it was the samizdat dissemination that, more than anything else, ensured the preservation and the early as well as the future impact of Shalamov's Gulag prose.
Detection of the furcation involvement of a multi-rooted molar using natural frequency analysis: A numerical approach
Authors: Wang C-H , Ou K-L , Chang W-J , Teng N-C , Yu J-J , Huang H-M
Published: February 2009

The aim of this study was to evaluate the potential for using the natural frequency (NF) as a parameter to detect vertical bone loss at the furcation of human molars as well as to assess the role that the surrounding bone plays in maintaining molar stability. A three-dimensional finite element model of the human maxillary molar was built. The NF values of the molar modal were calculated with one-sided, two-sided, and three-sided vertical bone loss. It was found that the change in the NF was less than 25 per cent in molars with a one-sided defect when the bone level varied by 10 mm from the cementoenamel junction. However, when a three-sided bony defect was simulated, the change in the NF ranged from 40 to 60 per cent. In addition, it was found that bone loss that had reached the furcation entrance (4 mm) resulted in a sharp change in the NF value. Furthermore, it was found that bone loss involving the mesial and distal surfaces resulted in a larger decrease in the NF value compared with bone loss involving the buccal and palatal surfaces. These results demonstrated that the bone surrounding the mesial and distal sides plays a more important role in maintaining molar stability than does the bone surrounding the buccal and palatal sides.
The accuracy and precision of a micro computer tomography volumetric measurement technique for the analysis of in-vitro tested total disc replacements
Authors: Vicars R , Fisher J , Hall R M
Published: February 2009

Total disc replacements (TDRs) in the spine have been clinically successful in the short term, but there are concerns over long-term failure due to wear, as seen in other joint replacements. Simulators have been used to investigate the wear of TDRs, but only gravimetric measurements have been used to assess material loss. Micro computer tomography (μCT) has been used for volumetric measurement of explanted components but has yet to be used for in-vitro studies with the wear typically less than < 20mm3 per 106 cycles. The aim of this study was to compare μCT volume measurements with gravimetric measurements and to assess whether μCT can quantify wear volumes of in-vitro tested TDRs. μCT measurements of TDR polyethylene cores were undertaken and the results compared with gravimetric assessments. The effects of repositioning, integration time, and scan resolution were investigated. The best volume measurement resolution was found to be ±3 mm3, at least three orders of magnitude greater than those determined for gravimetric measurements. In conclusion, the μCT measurement technique is suitable for quantifying in-vitro TDR polyethylene wear volumes and can provide qualitative data (e.g. wear location), and also further quantitative data (e.g. height loss), assisting comparisons with in-vivo and ex-vivo data. It is best used alongside gravimetric measurements to maintain the high level of precision that these measurements provide.
Trajectory tracking for a serial robot manipulator passing through singular configurations based on the adaptive kinematics Jacobian method
Authors: Hasan A T , Hamouda A M S , Ismail N , Aris I , Marhaban M H
Published: February 2009

This paper discusses the use of artificial neural networks (ANNs) as a method of trajectory tracking control for a robotic system. Using an ANN does not require any prior knowledge of the kinematics model of the system being controlled; the basic idea of this concept is the use of the ANN to learn the characteristics of the robot system rather than to specify an explicit robot system model.

In this approach, disadvantages of some schemes such as the fuzzy learning control, for example, have been elevated. Off-line training was performed for a geometric trajectory that is free of obstacles.

Studying the kinematics Jacobian of serial manipulators by using ANNs has two problems: one of these is the selection of the appropriate configuration of the network and the other is the generation of a suitable training dataset. In this approach, although this is very difficult in practice, training data were recorded experimentally from sensors fixed on each joint to overcome the effect of kinematics uncertainties present in the real world such as ill-defined linkage parameters, links flexibility, and backlashes in the gear train. Then two network configurations were compared to find the best configuration to be used. Finally, the simulation results were verified experimentally using a general six-degree-of-freedom (DOF) serial robot manipulator.
Rush: A simple and autonomous quadruped running robot
Authors: Zhang Z G , Kimura H
Published: February 2009

In this paper, the system design and analysis of a quadruped robot, Rush, are presented. The quadruped robot was fabricated to study autonomous and efficient running on flat and rough terrain. It is a compact, kneed, four-legged machine with only one actuator per compliant leg. A novel control strategy for the quadruped robot has been proposed in consideration of several engineering limitations on sensory feedback. Several simulation studies have already been performed to confirm the validity of the control strategy in the previous reports. In this paper, the results obtained from experiments with Rush are found to agree with the simulation results. The reported work may help improve the understanding of energy-efficient running locomotion and the simple control required to autonomously stabilize it on flat or rough terrain.
Model-driven development and multiprocessor implementation of a dynamic control algorithm for nanopositioning and nanomeasuring machines
Authors: Müller M , Fengler W , Amthor A , Ament C
Published: February 2009

This article presents a computationally intensive adaptive trajectory tracking control algorithm for dynamic control of nanopositioning and nanomeasuring machines. To realize the required high sample rate of the control algorithm, an embedded multiprocessor architecture has been chosen as development target. The model-oriented development approach studied here aims to narrow the gap between the control system design environment MATLAB/Simulink® and the actual distributed implementation on the custom platform by introducing a custom code generation target intending the utilization of automatic code generation facilities.
Forward path model predictive control using a non-minimal state-space form
Authors: Exadaktylos V , Taylor C J , Wang L , Young P C
Published: February 2009

This paper considers model predictive control (MPC) using a non-minimal state-space (NMSS) form, in which the state vector consists only of the directly measured system variables. Two control structures emerge from the analysis, namely the conventional feedback form and an alternative forward path structure. There is a close analogy with proportional-integral-plus (PIP) control system design, which is also based on the definition of an NMSS model with two control structures. However, the MPC/NMSS approach has the advantage of handling system constraints at the design stage. Also, since the NMSS model is obtained directly from the identified transfer function model, the covariance matrix for the parameter estimates can be used to evaluate the robustness of the predictive control system to model uncertainty using Monte Carlo simulation. The effectiveness of the approach is demonstrated by means of simulation examples, including the IFAC′93 benchmark and the ALSTOM non-linear gasifier problem. For the simulation examples considered here, the forward path form preserves the good performance properties of the original MPC/NMSS controller, while at the same time yielding improved robustness.
A genetically trained adaptive neuro-fuzzy inference system network utilized as a proportional-integral-derivative-like feedback controller for non-linear systems
Authors: Lutfy O F , Noor Mohd S B , Marhaban M H , Abbas K A
Published: February 2009

This paper presents a genetically trained PID (proportional-integral-derivative)-like ANFIS (adaptive neuro-fuzzy inference system) acting as a feedback controller to control non-linear systems. Three important issues are addressed in this paper, which are, first, the evaluation of the ANFIS as a PID-like controller; second, the utilization of the GA (genetic algorithm) alone to train the ANFIS controller, instead of the hybrid learning methods that are widely used in the literature; and, third, the determination of the input and output scaling factors for this controller by the GA. The GA, with real-coding operators, is used to adjust all of the ANFIS parameters, which include the input and output scaling factors, the centres and widths of the input membership functions (MFs), and the consequent parameters.

To show the effectiveness of this controller and its learning method, several non-linear plants, including the CSTR (continuous stirred tank reactor), have been selected to be controlled by this controller through simulation. Moreover, this controller's robustness to output disturbances has also been tested and the results clearly indicated the remarkable performance of this controller and its learning algorithm. In addition, the result of comparing the performance of this controller with a genetically tuned classical PID controller has shown the superiority of the PID-like ANFIS controller.
Multidisciplinary optimization of a catamaran's hydrofoil design with dynamic response surface and distributive processing
Authors: Tancredi T P , Augusto O B , Bennis F
Published: February 2009

This paper presents a rational approach to the design of a catamaran's hydrofoil applied within a modern context of multidisciplinary optimization. The approach used includes the use of response surfaces represented by neural networks and a distributed programming environment that increases the optimization speed. A rational approach to the problem simplifies the complex optimization model; when combined with the distributed dynamic training used for the response surfaces, this model increases the efficiency of the process. The results achieved using this approach have justified this publication.
Activity of Novel Antibiotic Lock Solutions in a Model Against Isolates of Catheter-Related Bloodstream Infections
Authors: Bookstaver P Brandon , Williamson John C , Tucker Brian Keith , Raad Issam I , Sherertz Robert J
Published: February 2009

Background:

Catheter-related bloodstream infections (CRBSIs) are a primary concern in patients with indwelling central venous catheters (CVCs). Instillation of an antibiotic lock solution may serve as an adjunctive therapy.

Objective:

To evaluate the efficacy of novel antibiotic–anticoagulant lock solutions using an in vitro model of CVC infection.

Methods:

The following lock solutions were evaluated: daptomycin 1 mg/mL (reconstituted with lactated Ringer's [LR]) plus heparin 5000 units/mL, tigecycline 0.5 mg/mL plus ethylenediaminete-traacetate (EDTA) 30 mg/mL, gentamicin 5 mg/mL plus EDTA 30 mg/mL, oefazolin 5 mg/mL plus heparin 5000 units/mL, and phosphate-buffered NaCI 0.9% as the control solution. Analysis was performed on Hickman catheter segments inoculated with the following organisms: methicillin-sensitive Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Staphylococcus epidermidis, and Pseudomonas aeruginosa. The catheters were incubated in the candidate lock, solutions for 0, 2, 4, and 24 hours. Student's t-tests were conducted to evaluate reduction in log10 colony-forming units/milliliter (cfu/mL) of individual lock solutions compared with the control solution. For each organism, analysis of variance and Student's t-tests were performed to determine whether differences existed among the lock solutions.

Results:

Gentamicin plus EDTA (G+EDTA) and tigecycline plus EDTA (Ti+EDTA) resulted in significant reductions (p < 0.05) of log10 cfu/mL at 24 hours for all organisms tested. Daptomycin, reconstituted in LR, plus heparin (D+LR+H) demonstrated potent activity against all staphylococcal species (p < 0.05). With respect to MRSA, G+EDTA displayed significantly better activity than Ti+EDTA and cefazolin plus heparin (p < 0.05), but there was no significant difference compared with D+LR+H. No antagonism was noted with the addition of anticoagulants to the solutions.

Conclusions:

Gentamicin, tigecycline, and daptomycin in combination with anticoagulants as lock solutions displayed potent activity against common pathogens responsible for CRBSIs. Each of these lock solutions deserves strong consideration for study in a clinical trial. Further data on compatibility and stability of these solutions are needed before routine clinical use can be recommended.
Trospium Chloride Treatment of Overactive Bladder
Authors: Biastre Kelly , Burnakis Thomas
Published: February 2009

Objective:

To review the pharmacology, pharmacokinetics, safety, and clinical application of trospium chloride for the management of overactive bladder (OAB).

Data Sources:

Clinical literature including both primary sources and review articles was accessed through MEDLINE, International Pharmaceutical Abstracts, and Cochrane databases from 1980 through January 8, 2009. Search terms included overactive bladder, urge urinary incontinence, muscarinic receptor antagonists, and urinary frequency. Further data sources were identified from bibliographies of selected articles.

Study Selection and Data Extraction:

Basic pharmacology data were extracted from animal studies and pharmacokinetic data were gathered from human studies. Multicenter, parallel, randomized, double-blind, placebo-controlled studies were included to describe the efficacy and adverse effects of trospium.

Data Synthesis:

Trospium chloride is an antimuscarinic agent indicated for the treatment of OAB with symptoms of urge urinary incontinence, urgency, and urinary frequency. Trospium has 3 chemical and pharmacokinetic properties unique among antimuscarinic agents: it is a positively charged quaternary ammonium compound with minimal central nervous system penetration; it is not metabolized by the cytochrome P450 system, resulting in a lower tendency for drug interactions; and it is excreted mainly unchanged in the urine as the active parent compound, providing local activity to achieve early onset of clinical effect and prolonged efficacy. In two 12-week, randomized, placebo-controlled clinical studies in adults with OAB, trospium 20 mg twice daily was more effective than placebo in reducing the number of micturitions per 24 hours, reducing the number of urge incontinence episodes per week, and increasing the volume of urine voided per micturition. Placebo-controlled trials report efficacy with trospium in treatment of OAB; comparative trials with other anticholinergic agents are limited. Current therapy of OAB consists primarily of anticholinergic drugs such as oxybutynin, which are associated with therapy-limiting adverse effects. Because the prevalence of OAB is greatest among the elderly, safety considerations regarding renal function must be noted, with dosage adjustment required in patients with severe renal impairment.

Conclusions:

Whether the pharmacodynamic properties of trospium make it superior to other therapies will require considerable additional experience with the drug. For now, it appears to be a feasible alternative for patients who cannot tolerate oxybutynin.