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Suitable Candidates (suitable + candidate)
Selected AbstractsDS/CDMA throughput of a multi-hop sensor network in a Rayleigh fading underwater acoustic channelCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 8 2007Choong Hock Mar Abstract Asynchronous half-duplex Direct-Sequence Code-Division Multiple-Access (DS/CDMA) is a suitable candidate for the MAC protocol design of underwater acoustic (UWA) sensor networks owing to its many attractive features. Our ad-hoc multi-hop network is infrastructureless in that it is without centralized base stations or power control. Hence, we develop an asynchronous distributed half-duplex control protocol to regulate between the transmitting and receiving phases of transmissions. Furthermore, multi-hop communications are very sensitive to the time variability of the received signal strength in the fading channel and the ambient noise dominated by snapping shrimp in harsh underwater environments, because a broken link in the multi-hop path is enough to disrupt communications and initiate new route searches. In our configuration, we use the Ad hoc On-demand Distance Vector (AODV) routing protocol optimized for UWA networks. Empirical studies show that we can model the channel as a slow-varying frequency non-selective Rayleigh fading channel. We theoretically analyze the throughput of our configuration by considering three salient features: the ability of the receiver to demodulate the data, the effect of our control protocol and the effect of disconnections on the generation of routing packets. The throughput under various operating conditions is then examined. It is observed that at optimal node separation, the throughput is improved by a factor of 10. Copyright © 2007 John Wiley & Sons, Ltd. [source] Bottom-Up Engineering of Subnanometer Copper Diffusion Barriers Using NH2 -Derived Self-Assembled MonolayersADVANCED FUNCTIONAL MATERIALS, Issue 7 2010Arantxa Maestre Caro Abstract A 3-aminopropyltrimethoxysilane-derived self-assembled monolayer (NH2SAM) is investigated as a barrier against copper diffusion for application in back-end-of-line (BEOL) technology. The essential characteristics studied include thermal stability to BEOL processing, inhibition of copper diffusion, and adhesion to both the underlying SiO2 dielectric substrate and the Cu over-layer. Time-of-flight secondary ion mass spectrometry and X-ray spectroscopy (XPS) analysis reveal that the copper over-layer closes at 1,2-nm thickness, comparable with the 1.3-nm closure of state-of-the-art Ta/TaN Cu diffusion barriers. That the NH2SAM remains intact upon Cu deposition and subsequent annealing is unambiguously revealed by energy-filtered transmission electron microscopy supported by XPS. The SAM forms a well-defined carbon-rich interface with the Cu over-layer and electron energy loss spectroscopy shows no evidence of Cu penetration into the SAM. Interestingly, the adhesion of the Cu/NH2SAM/SiO2 system increases with annealing temperature up to 7.2,J m,2 at 400,°C, comparable to Ta/TaN (7.5,J m,2 at room temperature). The corresponding fracture analysis shows that when failure does occur it is located at the Cu/SAM interface. Overall, these results demonstrate that NH2SAM is a suitable candidate for subnanometer-scale diffusion barrier application in a selective coating for copper advanced interconnects. [source] Non-invasive systemic drug delivery: Developability considerations for alternate routes of administrationJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 1 2010Neil R. Mathias Abstract Over the past few decades alternate routes of administration have gained significant momentum and attention, to complement approved drug products, or enable those that cannot be delivered by the oral or parenteral route. Intranasal, buccal/sublingual, pulmonary, and transdermal routes being the most promising non-invasive systemic delivery options. Considering alternate routes of administration early in the development process may be useful to enable new molecular entities (NME) that have deficiencies (extensive first-pass metabolism, unfavorable physicochemical properties, gastro-intestinal adverse effects) or suboptimal pharmacokinetic profiles that are identified in preclinical studies. This review article describes the various delivery considerations and extraneous factors in developing a strategy to pursue an alternate route of administration for systemic delivery. The various delivery route options are outlined with their pros and cons; key criteria and physicochemical attributes that would make a drug a suitable candidate are discussed; approaches to assess delivery feasibility, toxicity at the site of delivery, and overall developability potential are described; and lastly, product trends and their disease implications are highlighted to underscore treatment precedence that help to build scientific rationale for the pursuit of an alternate route of administration. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:1,20, 2010 [source] Stability and hydrolysis kinetics of spirosuccinimide type inhibitors of aldose reductase in aqueous solution and retardation of their hydrolysis by the target enzymeJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 4 2008Masuo Kurono Abstract The stability and the hydrolysis kinetics of spirosuccinimide type aldose reductase (AR) inhibitors, SX-3030 (racemate) and its optical enantiomers (R - and S -isomers), were investigated in aqueous solution. The hydrolysis followed pseudo-first-order kinetics and showed significant pH dependence. Maximum solution stability was observed below pH 2.4, whereas the hydrolysis was gradually catalyzed by hydroxide ion at neutral to alkaline pH while the compounds exhibiting moderate pH-independent stability at acidic to neutral conditions (pH 4,7) to enable oral administration. A pK of 3.7 was obtained from the pH-rate profile, but this kinetically derived pK is approximately 2 pH units below the pK of the parent compounds, suggesting the presence of an acidic intermediate involved in the hydrolysis process. These findings, together with structural analysis, support the notion that the hydrolysis would proceed via nucleophilic attack of a water molecule or hydroxide ion on the scissile carbonyl bond of the succinimide ring to form a succinamic acid intermediate that has a ,-keto acid structure, followed by decarboxylation to give a racemized succinimide ring-opened product. On the other hand, the interconversion of the R - and S -isomers did not occur during hydrolysis; however, the hydrolysis of the R -isomer was markedly suppressed by the target enzyme AR whereas that of the S -isomer was not, indicating a high degree of complementarity of interacting surfaces between the R -isomer and the enzyme. The results in the present study could provide useful clues for facilitating the appropriate stabilization strategies as well as for evaluating the pharmacological effects on target tissues in vivo, and suggested that the R -isomer may be a suitable candidate as AR inhibitor. © 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:1468,1483, 2008 [source] Synthesis and hydrolytic behaviour of 2-mercaptoethyl ibuprofenate,polyethylene glycol conjugate as a novel transdermal prodrugJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 4 2003Soodabeh Davaran ABSTRACT Thiolated derivatives of ibuprofen and its polyethylene glycol ester were synthesized via condensation of 2-mercaptoethyl ibuprofenate with carboxy-terminated polyethylene glycol. The release of ibuprofen from this polymeric prodrug has been studied under conditions simulating those encountered in the skin. The polymeric prodrug of ibuprofen was found to undergo pH-dependent hydrolysis, ranging from negligible hydrolysis at pH 4 to 23.9% hydrolysis at pH 8.5 (15% at pH 7.4) after 48 h at 37 °C. The polymer,drug conjugate was subjected to enzymatic hydrolysis in human plasma. The polymer showed considerable enzymatic hydrolysis (68% after 48 h). The results showed that the polymeric prodrug model of non-steroidal anti-inflammatory drugs (NSAIDs) described here can be used in topical formulations of NSAIDs. It is expected that the novel thiol derivative will have both enhanced transdermal penetration and stability to oxidation which make it a suitable candidate for transdermal formulations. [source] Characterization of the Coat Protein Gene of Cymbidium mosaic virus Isolates from IndiaJOURNAL OF PHYTOPATHOLOGY, Issue 5 2006A. R. Sherpa Abstract The variability in the coat protein (CP) gene sequence of Cymbidium mosaic virus (CymMV) that naturally infects orchids worldwide was investigated. Samples were collected from different regions of India, and the gene encoding the CP of nine isolates was specifically amplified by reverse-transcription polymerase chain reaction. The amplified product obtained was cloned, sequenced and multiple sequence alignment of deduced amino acid (aa) sequences revealed considerable homology to CymMV isolates from other countries. The nucleotide sequences and the amino acid sequences were found to be 85,100% identical and 65,100% respectively. Such high sequence conservation suggests that the CymMV CP gene is highly conserved and is a suitable candidate for the development of diagnostic procedures and to provide transgenic resistance to orchids cultivated in different geographical locations. Although recombination is not common among CymMV isolates, one isolate from Cymbidium was found to be a recombinant between a Korean and a Thai isolate of the virus. IHBT communication no: 0451. [source] Wear and microstructural characteristics of spray atomized zircon sand reinforced LM13 alloy.MATERIALWISSENSCHAFT UND WERKSTOFFTECHNIK, Issue 7 2010Verschleiß- und Gefügecharakteristik von sprühkompaktierter mit Zirkoniumsand verstärkter LM13 Legierung Verbundwerkstoff; Aluminiummatrix; Sprühkompaktieren; Verschleißverhalten Abstract The requirement of the high performance light weight materials demands the development of varieties of materials within the economical range to get it commercialized. Light weight aluminium alloys are used in several structural applications like automotive, aerospace, defense industry and other fields of engineering. The ceramic particle reinforced aluminium metal matrix composites (AMCs) have emerged as a suitable candidate for commercial applications. A variety of processing routes have been adopted to manufacture AMCs. In the present work LM13 alloy reinforced with zircon sand is formed via spray forming. During experimentation a self prepared convergent-divergent nozzle is used for inert gas atomization of the melt which is subsequently deposited on copper substrate placed vertically below the atomizer. The zircon sand particles are injected in the atomization zone by external injectors aligned perpendicular to the gas atomization axis. Zircon sand has been found to have new promising economical commercial candidate due to its easy availability and good mechanical properties like high hardness, high modulus of elasticity and good thermal stability. The microhardness of cast alloy and spray formed composite shows that the spray formed zircon sand reinforced composite has higher hardness. Also the lower wear rate has been observed in case of the zircon sand reinforced AMC as compared to LM13 alloy. This behaviour is further analyzed in light of microstructural features of the spray deposited composite using optical and scanning electron microscope (SEM). A comparative study of this material (LM13/Zircon sand) with the parent alloy (LM13) is presented in this work. [source] Preparation and characterization of pulse electrodeposited GaAs filmsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 5 2006K. R. Murali Abstract GaAs is a III,V compound possessing high mobility and a direct band gap of 1.43 eV, making it a very suitable candidate for photovoltaic applications. Thin GaAs films were prepared by plating an aqueous solution containing GaCl3 and As2O3 at a pH of 2 and at room temperature. The current density was kept at 50 mA cm,2 and the duty cycle was varied in the range 10,50%. The films were deposited on titanium, nickel and tin oxide coated glass substrates. Films exhibited polycrystalline nature with peaks corresponding to single-phase GaAs. Optical absorption measurements indicated a direct band gap of 1.40 eV. Atomic force microscope measurements indicated uniform coverage with large crystallites for the films deposited at higher duty cycles. Photoelectrochemical cells were made using the films as photoelectrodes and graphite as counter electrode in 1 M polysulphide electrolyte. At 60 mW cm,2 illumination, an open-circuit voltage of 0.5 V and a short-circuit current density of 5.0 mA cm,2 were observed for the films deposited at a duty cycle of 50%. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Carrier-induced refractive index change in InNPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 2 2008C. Bulutay Abstract Rapid development of InN technology demands comprehensive assessment of the electronic and optoelectronic potential of this material. In this theoretical work the effect of free electrons on the optical properties of the wurtzite phase of InN is investigated. The blue shift of the optical absorption edge by the free-carrier band filling is known as the Burstein-Moss effect for which InN offers to be a very suitable candidate as has been recently demonstrated experimentally. Due to well known Kramers-Kronig relations, a change in absorption is accompanied by a change in the index of refraction. Considering n-type InN samples with free electron concentrations ranging from 5×1017 to 5×1020 cm,3, and employing a nonlocal empirical pseudopotential band structure, it is shown that this leads to a few percent change of the index of refraction. These carrier-induced refractive index changes can be utilized in optical switches, futhermore it needs to be taken into account in the design of InN-based optical devices such as lasers and optical modulators. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Antigenotoxic effect of extract from Cynara cardunculus L.PHYTOTHERAPY RESEARCH, Issue 1 2008E. Miadokova Abstract The extract of artichoke Cynara cardunculus L. (CCE) was investigated for its potential antigenotoxic and antioxidant effects using four experimental model systems. In the Saccharomyces cerevisiae mutagenicity/antimutagenicity assay, CCE significantly reduced the frequency of 4-nitroquinoline- N -oxide-induced revertants at the ilv1 locus and mitotic gene convertants at the trp5 locus in the diploid Saccharomyces cerevisiae tester strain D7. In the simultaneous toxicity and clastogenicity/anticlastogenicity assay, it exerted an anticlastogenic effect against N-nitroso- N,-methylurea-induced clastogenicity in the plant species Vicia sativa L. On the contrary, despite CCE not being mutagenic itself, in the preincubation Ames assay with metabolic activation, it significantly increased the mutagenic effect of 2-aminofluorene in the bacterial strain Salmonella typhimurium TA98. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay, CCE exhibited considerable antioxidant activity. The SC50 value representing 0.0054% CCE corresponds to an antioxidant activity of 216.8 µm ascorbic acid which was used as a reference compound. Although the mechanism of CCE action still remains to be elucidated, different possible mechanisms are probably involved in the CCE antigenotoxic effects. It could be concluded that CCE is of particular interest as a suitable candidate for an effective chemopreventive agent. Copyright © 2007 John Wiley & Sons, Ltd. [source] Intra-hepatic arterial administration with miriplatin suspended in an oily lymphographic agent inhibits the growth of human hepatoma cells orthotopically implanted in nude ratsCANCER SCIENCE, Issue 1 2009Mitsuharu Hanada Miriplatin is a lipophilic platinum complex which contains myristates as leaving groups and diaminocyclohexane as a carrier ligand. In order to examine in vivo the antitumor activities of miriplatin suspended in an oily lymphographic agent (Lipiodol Ultra-Fluide®, LPD) against human hepatocellular carcinoma (HCC) after the intra-hepatic arterial administration, we have developed a novel orthotopic model of HCC in which the human hepatoma cell line Li-7 was successively implanted and maintained in the liver of nude rats. Li-7 tumors established in nude rat livers displayed a trabecular structure similar to their original morphology, and were exclusively supplied by the hepatic artery, suggesting that they exhibited in part the conditions of human HCC. Miriplatin suspended in LPD (miriplatin/LPD) administered into the hepatic artery of this model dose-dependently inhibited the growth of Li-7 tumors without markedly enhancing body weight loss and caused a significant reduction in the growth rate at a dose of 400 µg/head compared to LPD alone. In addition, at the therapeutic dose, miriplatin/LPD as well as cisplatin suspended in LPD (400 µg/head) was shown to be more active than zinostatin stimalamer suspended in LPD (20 µg/head) against Li-7 tumors after a single intra-hepatic arterial administration. These results suggest miriplatin to be a suitable candidate for use in transarterial chemoembolization (Cancer Sci 2009; 100: 189,194) [source] Follicular Unit Extraction: Minimally Invasive Surgery for Hair TransplantationDERMATOLOGIC SURGERY, Issue 8 2002William R. Rassman MD background. Follicular Unit Transplantation (FUT) is performed using large numbers of naturally occuring individual follicular units obtained by single-strip harvesting and stereo-microscopic dissection. Donor wound scarring from strip excision, although an infrequent complication, still concerns enough patients that an alternative solution is warranted. objective. The purpose of this paper is to introduce Follicular Unit Extraction (The FOX Procedure), in which individual follicular units are removed directly from the donor region through very small punch excisions, and to describe a test (The FOX Test) that determines which patients are candidates for this procedure. This paper explores the nuances, limitations, and practical aspects of Follicular Unit Extraction (FUE). methods. FUE was performed using 1-mm punches to separate follicular units from the surrounding tissue down to the level of the mid dermis. This was followed by extraction of the follicular units with forceps. The FOX test was developed to determine which patients would be good candidates for the procedure. The test was performed on 200 patients. Representative patients who were FOX-positive and FOX-negative were studied histologically. results. The FOX Test can determine which patients are suitable candidates for FUE. Approximately 25% of the patients biopsied were ideal candidates for FUE and 35% of the patients biopsied were good candidates for extraction. conclusion. FUE is a minimally invasive approach to hair transplantation that obviates the need for a linear donor incision. This technique can serve as an important alternative to traditional hair transplantation in certain patients. [source] Cytoprotection of beta cells: rational gene transfer strategiesDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 3 2006Cillian McCabe Abstract Gene transfer to pancreatic islets may prove useful in preventing islet cell destruction and prolonging islet graft survival after transplantation in patients with type 1 diabetes mellitus (T1DM). Potentially, a host of therapeutically relevant transgenes may be incorporated into an appropriate gene delivery vehicle and used for islet modification. An increasing understanding of the molecular pathogenesis of immune-mediated beta cell death has served to highlight molecules which have become suitable candidates for promoting islet cell survival in the face of oxidative stress. This review aims to give an overview of some conventional gene transfer strategies aimed at promoting islet cell survival in the face of cytokine onslaught. These strategies target three aspects of islet cell physiology: redox status and antioxidant defence, anti-apoptotic gene expression and mediators of cytokine signal transduction pathways. Copyright © 2006 John Wiley & Sons, Ltd. [source] New potential treatments for protection of pancreatic B-cell function in Type 1 diabetesDIABETIC MEDICINE, Issue 11 2008S. Cernea Abstract Type 1 diabetes mellitus results from the progressive and specific autoimmune destruction of insulin-secreting pancreatic B-cells, which develops over a period of years and continues after the initial clinical presentation. The ultimate goal of therapeutic intervention is prevention or reversal of the disease by the arrest of autoimmunity and by preservation/restoration of B-cell mass and function. Recent clinical trials of antigen-specific or non-specific immune therapies have proved that modulation of islet specific autoimmunity in humans and prevention of insulin secretion loss in the short term after the onset of disease is achievable. The identification of suitable candidates for therapy, appropriate dosage and timing, specificity of intervention and the side-effect profile are crucial for the success of any approach. Considering the complexity of the disease, it is likely that a rationally designed approach of combined immune-based therapies that target suppression of B-cell specific autoreactivity and maintenance of immune tolerance, coupled with islet regeneration or replacement of the destroyed B-cell mass, will prove to be most effective in causing remission/reversal of disease in a durable fashion. [source] Strategies for surgical treatment of epilepsies in developing countriesEPILEPSIA, Issue 3 2008Ali A. Asadi-Pooya Summary Epilepsy surgery has been proved to be efficacious, safe and cost-effective in developing countries. However, the success of epilepsy surgery depends on selecting suitable candidates based on the available resources and technologies. Some of the challenges to provide appropriate surgical treatment for epilepsy patients in developing countries include providing human and technological resources and developing realistic presurgical protocols. Detection of ideal candidates for epilepsy surgery is possible for well-trained epileptologists with the help of basic investigative technologies, for example, magnetic resonance imaging (MRI) and electroencephalography (EEG). Patients with potentially epileptogenic, well-circumscribed lesions on MRI and patients with mesial temporal lobe epilepsy (MTLE) are reasonable candidates for surgery. Palliative epilepsy surgeries include corpus callosotomy and other disconnections. These operations are feasible in developing countries with a knowledgeable team consisting of an epileptologist, neurosurgeon and technicians and with using MRI and EEG as basic investigative technologies. [source] Bacterial adhesion to diamond-like carbon as compared to stainless steelJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2009Antti Soininen Abstract Recent studies suggest that diamond-like carbon (DLC) coatings are suitable candidates for application on biomedical devices and implants, due to their high hardness, low friction, high wear and corrosion resistance, chemical inertness, smoothness, and tissue and blood compatibility. However, most studies have neglected the potential susceptibility of DLC coatings to bacterial adhesion, which is the first step in the development of implant-related infections. This study compares adhesion of seven bacterial strains, commonly implicated in implant-related infections, to tetrahedral amorphous carbon, with their adhesion to AISI 316L surgical steel. The results show that bacterial adhesion to DLC was similar to the adhesion to commonly used stainless steel. This suggests that DLC coating can be advantageously used on implants made of AISI 316L or other materials without increasing the risk to implant-related infections. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009 [source] Conformational polymorphism in aripiprazole: Preparation, stability and structure of five modificationsJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 6 2009Doris E. Braun Abstract Five phase-pure modifications of the antipsychotic drug aripiprazole were prepared and characterized by thermal analysis, vibrational spectroscopy and X-ray diffractometry. All modifications can be produced from solvents, form I additionally by heating of form X° to ,120°C (solid,solid transformation) and form III by crystallization from the melt. Thermodynamic relationships between the polymorphs were evaluated on the basis of thermochemical data and visualized in a semi-schematic energy/temperature diagram. At least six of the ten polymorphic pairs are enantiotropically and two monotropically related. Form X° is the thermodynamically stable modification at 20°C, form II is stable in a window from about 62,77°C, and form I above 80°C (high-temperature form). Forms III and IV are triclinic (), I and X° are monoclinic (P21) and form II orthorhombic (Pna21). Each polymorph exhibits a distinct molecular conformation, and there are two fundamental N,HO hydrogen bond synthons (catemers and dimers). Hirshfeld surface analysis was employed to display differences in intermolecular short contacts. A high kinetic stability was observed for three metastable polymorphs which can be categorized as suitable candidates for the development of solid dosage forms. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:2010,2026, 2009 [source] Liver organ allocation for hepatocellular carcinoma: Are we sure?LIVER TRANSPLANTATION, Issue 7 2003J. Wallis Marsh Of patients with hepatocellular carcinoma (HCC), 70% to 90% present with cirrhosis. Accordingly, liver transplantation ,LT), not liver resection, currently remains the only possibility of cure for these patients. Because there is a severe shortage of liver organ donors, not all patients in need can be offered LT. Therefore, transplant listing criteria simultaneously must determine the greatest number of suitable candidates for transplantation while rejecting the smallest number of those who could benefit from LT. The objective of this study was to determine the outcome of patients with HCC who are denied LT by current listing criteria. Of patients who are being denied liver transplantation by the current United Network for Organ Sharing listing criteria (but who were transplanted before the current guidelines took effect(, 27% to 49% were cured by this procedure. The listing criteria for LT in the presence of HCC should reflect the minimum acceptable )not maximum acceptable) recurrence-free survival rate and must reflect a consensus of the transplant community. [source] Interpreting the significance of drinking by alcohol-dependent liver transplant patients: Fostering candor is the key to recoveryLIVER TRANSPLANTATION, Issue 6 2000Robert M. Weinrieb Few studies have examined the value of treating alcohol addiction either before or after liver transplantation. Nevertheless, most liver transplant programs and many insurance companies require 6 months to 1 year of abstinence from alcohol as a condition of eligibility for liver transplantation (the 6-month rule). We believe there are potentially harsh clinical consequences to the implementation of this rule. For example, the natural history of alcohol use disorders often involves brief fallbacks to drinking ("slips"), but when alcoholic liver transplant candidates slip, most are removed from consideration for transplantation or are required to accrue another 6 months of sobriety. Because there is no alternative treatment to liver transplantation for most patients with end-stage liver disease, the 6-month rule could be lethal in some circumstances. In this review, we survey the literature concerning the ability of the 6-month rule to predict drinking by alcoholic patients who undergo liver transplantation and examine its impact on the health consequences of drinking before and after liver transplantation. We believe that fostering candor between the alcoholic patient and the transplant team is the key to recovery from alcoholism. We conclude that it is unethical to force alcoholic liver patients who have resumed alcohol use while waiting for or after transplantation to choose between hiding their drinking to remain suitable candidates for transplantation or risk death by asking for treatment of alcoholism. Consequently, we advocate a flexible approach to clinical decision making for the transplant professional caring for an alcoholic patient who has resumed drinking and provide specific guidelines for patient management. [source] The use of topography-based parameters for the assessment and prediction of surface wearLUBRICATION SCIENCE, Issue 1 2000I. Sherrington Abstract This paper examines the use of surface parameters as ,tools' for assessing and predicting surface wear. It begins by briefly reviewing other work published on wear assessment based on entirely topography-based parameters, and concludes that other elements of surface condition are needed, in addition to topography, to assess and characterise the contact if topography-based parameters are to be employed to predict wear. This paper discusses why areal measurements of bearing area and plasticity index are suitable candidates as a basis for assessing and predicting surface wear, and outlines the potential value of using these parameters in conjunction with a wear equation. The validity of this suggestion is illustrated by some preliminary data from a series of pin-on-disc wear experiments involving areal assessments of the bearing area and plasticity index of the rough tip of a brass pin. Predictions of the first stage of a wear simulation are compared to experimental data, and the paper concludes by presenting some general conclusions and suggestions about how the work could be developed. [source] Anterior versus posterior approach in reconstruction of infected nonunion of the tibia using the vascularized fibular graft: potentialities and limitationsMICROSURGERY, Issue 3 2002Sherif M. Amr M.D. The potentialities, limitations, and technical pitfalls of the vascularized fibular grafting in infected nonunions of the tibia are outlined on the basis of 14 patients approached anteriorly or posteriorly. An infected nonunion of the tibia together with a large exposed area over the shin of the tibia is better approached anteriorly. The anastomosis is placed in an end-to-end or end-to-side fashion onto the anterior tibial vessels. To locate the site of the nonunion, the tibialis anterior muscle should be retracted laterally and the proximal and distal ends of the site of the nonunion debrided up to healthy bleeding bone. All the scarred skin over the anterior tibia should be excised, because it becomes devitalized as a result of the exposure. To cover the exposed area, the fibula has to be harvested with a large skin paddle, incorporating the first septocutaneous branch originating from the peroneal vessels before they gain the upper end of the flexor hallucis longus muscle. A disadvantage of harvesting the free fibula together with a skin paddle is that its pedicle is short. The skin paddle lies at the antimesenteric border of the graft, the site of incising and stripping the periosteum. In addition, it has to be sutured to the skin at the recipient site, so the soft tissues (together with the peroneal vessels), cannot be stripped off the graft to prolong its pedicle. Vein grafts should be resorted to, if the pedicle does not reach a healthy segment of the anterior tibial vessels. Defects with limited exposed areas of skin, especially in questionable patency of the vessels of the leg, require primarily a fibula with a long pedicle that could easily reach the popliteal vessels and are thus better approached posteriorly. In this approach, the site of the nonunion is exposed medial to the flexor digitorum muscle and the proximal and distal ends of the site of the nonunion debrided up to healthy bleeding bone. No attempt should be made to strip the scarred skin off the anterior aspect of the bone lest it should become devitalized. Any exposed bone on the anterior aspect should be left to granulate alone. This occurs readily when stability has been regained at the fracture site after transfer of the free fibula. The popliteal and posterior tibial vessels are exposed, and the microvascular anastomosis placed in an end-to-side fashion onto either of them, depending on the length of the pedicle and the condition of the vessels themselves. To obtain the maximal length of the pedicle of the graft, the proximal osteotomy is placed at the neck of the fibula after decompressing the peroneal nerve. The distal osteotomy is placed as distally as possible. After detaching the fibula from the donor site, the proximal part of the graft is stripped subperiosteally, osteotomized, and discarded. Thus, a relatively long pedicle could be obtained. To facilitate subperiosteal stripping, the free fibula is harvested without a skin paddle. In this way, the use of a vein graft could be avoided. Patients presenting with infected nonunions of the tibia with extensive scarring of the lower extremity, excessively large areas of skin loss, and with questionable patency of the anterior and posterior tibial vessels are not suitable candidates for the free vascularized fibular graft. Although a vein graft could be used between the recipient popliteal and the donor peroneal vessels, its use decreases flow to the graft considerably. These patients are better candidates for the Ilizarov bone transport method with or without free latissimus dorsi transfer. © 2002 Wiley-Liss, Inc. MICROSURGERY 22:91,107 2002 [source] Pretreatment Psychosocial Variables as Predictors of Outcomes Following Lumbar Surgery and Spinal Cord Stimulation: A Systematic Review and Literature SynthesisPAIN MEDICINE, Issue 4 2009James Celestin MD ABSTRACT Background., In the multimodal treatment approach to chronic back pain, interventional back procedures are often reserved for those who do not improve after more conservative management. Psychological screening prior to lumbar surgery or spinal cord stimulation (SCS) has been widely recommended to help identify suitable candidates and to predict possible complications or poor outcome from treatment. However, it remains unclear which, if any, variables are most predictive of pain-related treatment outcomes. Objective., The intent of this article is to perform a systematic review to examine the relationship between presurgical predictor variables and treatment outcomes, to review the existing evidence for the benefit of psychological screening prior to lumbar surgery or SCS, and to make treatment recommendations for the use of psychological screening. Results., Out of 753 study titles, 25 studies were identified, of which none were randomized controlled trials and only four SCS studies met inclusion criteria. The methodological quality of the studies varied and some important shortcomings were identified. A positive relationship was found between one or more psychological factors and poor treatment outcome in 92.0% of the studies reviewed. In particular, presurgical somatization, depression, anxiety, and poor coping were most useful in helping to predict poor response (i.e., less treatment-related benefit) to lumbar surgery and SCS. Older age and longer pain duration were also predictive of poorer outcome in some studies, while pretreatment physical findings, activity interference, and presurgical pain intensity were minimally predictive. Conclusions., At present, while there is insufficient empirical evidence that psychological screening before surgery or device implantation helps to improve treatment outcomes, the current literature suggests that psychological factors such as somatization, depression, anxiety, and poor coping, are important predictors of poor outcome. More research is needed to show if early identification and treatment of these factors through psychological screening will enhance treatment outcome. [source] Time Spent on Treatment of Atopic Dermatitis: A New Method of Measuring Pediatric Morbidity?PEDIATRIC DERMATOLOGY, Issue 6 2004Elisabeth A. Holm M.D. The TSOT (min/day) was studied in a group of 42 children with atopic dermatitis (AD) (16 girls and 26 boys; mean age 7.07 years). The TSOT included time spent on all types of topical treatment, on extra cleaning, and on visits to doctors. Objective Scoring Atopic Dermatitis (SCORAD) assessment was performed at each visit. A significant correlation was found between TSOT and SCORAD scores for all visits (p < 0.0001). There was no correlation between TSOT and age or sex or between TSOT/SCORAD and age (p < 0.08). For the 65 visits (by 42 children), TSOT/SCORAD ranged from 0.08 min/point to 28.67 min/point. Older children (10,15 years of age) had a lower TSOT/SCORAD ratio compared to younger children (1,5 years of age). Our data suggest that TSOT in itself may be a useful measure of morbidity among pediatric AD patients. It is speculated that patients with a very high TSOT/SCORAD rate or a very low rate have coping problems and would therefore be suitable candidates for intensified efforts in programs such as "eczema schools." [source] PAN,DR-Binding Hsp60 self epitopes induce an interleukin-10,mediated immune response in rheumatoid arthritisARTHRITIS & RHEUMATISM, Issue 7 2009Huib de Jong Objective Human Hsp60 is expressed in the joints of patients with rheumatoid arthritis (RA) and can elicit a regulatory T cell response in the peripheral blood and synovial fluid. However, Hsp60 can also trigger strong proinflammatory pathways. Thus, to understand the nature of these Hsp60-directed responses in RA, it is necessary to study such responses at the molecular, epitope-specific level. This study was undertaken to characterize the disease specificity and function of pan,DR-binding Hsp60,derived epitopes as possible modulators of autoimmune inflammation in RA. Methods Lymphocyte proliferation assays (using 3H-thymidine incorporation and carboxyfluorescein diacetate succinimidyl ester [CFSE] staining) and measurement of cytokine production (using multiplex immunoassay and intracellular staining) were performed after in vitro activation of peripheral blood mononuclear cells from patients with RA, compared with healthy controls. Results A disease (RA),specific immune recognition, characterized by T cell proliferation as well as increased production of tumor necrosis factor , (TNF,), interleukin-1, (IL-1,), and IL-10, was found for 3 of the 8 selected peptides in patients with RA as compared with healthy controls (P < 0.05). Intracellular cytokine staining and CFSE labeling showed that CD4+ T cells were the subset primarily responsible for both the T cell proliferation and the cytokine production in RA. Interestingly, the human peptides had a remarkably different phenotype, with a 5,10-fold higher IL-10:TNF, ratio, compared with that of the microbial peptides. Conclusion These results suggest a disease-specific immune-modulatory role of epitope-specific T cells in the inflammatory processes of RA. Therefore, these pan,DR-binding epitopes could be used as a tool to study the autoreactive T cell response in RA and might be suitable candidates for use in immunotherapy. [source] Interobserver Agreement in Assessment of Clinical Variables in Children with Blunt Head TraumaACADEMIC EMERGENCY MEDICINE, Issue 9 2008Marc H. Gorelick MD Abstract Objectives:, To be useful in development of clinical decision rules, clinical variables must demonstrate acceptable agreement when assessed by different observers. The objective was to determine the interobserver agreement in the assessment of historical and physical examination findings of children undergoing emergency department (ED) evaluation for blunt head trauma. Methods:, This was a prospective cohort study of children younger than 18 years evaluated for blunt head trauma at one of 25 EDs in the Pediatric Emergency Care Applied Research Network (PECARN). Patients were excluded if injury occurred more than 24 hours prior to evaluation, if neuroimaging was obtained at another hospital prior to evaluation, or if the patient had a clinically trivial mechanism of injury. Two clinicians independently completed a standardized clinical assessment on a templated data form. Assessments were performed within 60 minutes of each other and prior to clinician review of any neuroimaging (if obtained). Agreement between the two observers beyond that expected by chance was calculated for each clinical variable, using the kappa (,) statistic for categorical variables and weighted kappa for ordinal variables. Variables with a lower 95% confidence limit (LCL) of , > 0.4 were considered to have acceptable agreement. Results:, Fifteen-hundred pairs of observations were obtained. Acceptable agreement was achieved in 27 of the 32 variables studied (84%). Mechanism of injury (low, medium, or high risk) had , = 0.83. For subjective symptoms, kappa ranged from 0.47 (dizziness) to 0.93 (frequency of vomiting); all had 95% LCL > 0.4. Of the physical examination findings, kappa ranged from 0.22 (agitated) to 0.89 (Glasgow Coma Scale [GCS] score). The 95% LCL for kappa was <0.4 for four individual signs of altered mental status and for quality (i.e., boggy or firm) of scalp hematoma if present. Conclusions:, Both subjective and objective clinical variables in children with blunt head trauma can be assessed by different observers with acceptable agreement, making these variables suitable candidates for clinical decision rules. [source] Percutaneous closure of patent foramen ovale guided by intracardiac echocardiography and performed through the transfemoral approach in the presence of previously placed inferior vena cava filters: A case seriesCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 2 2004Hany Awadalla MD Abstract We present three patients with cryptogenic stroke who underwent transcatheter closure of a patent foramen ovale. All patients have had history of deep venous thrombosis and pulmonary embolism with placement of inferior vena caval filters. The patients were not initially considered suitable candidates for the procedure because of risk of dislodgment of previously implanted inferior vena cava filter. Catheter Cardiovasc Interv 2004;63:242,246. © 2004 Wiley-Liss, Inc. [source] Day case stapled haemorrhoidopexy for prolapsing haemorrhoidsCOLORECTAL DISEASE, Issue 1 2006G. C. Beattie Abstract Objective, Conventional surgical management of prolapsing haemorrhoids is by excisional haemorrhoidectomy. Postoperative pain has restricted the application of such procedures in the day case setting. These operations remain associated with a period of restricted activity. The use of circular stapling devices as an alternative to the excisional approach in the management of haemorrhoids has been described. This study reports our experience of stapled haemorrhoidopexy as a day case procedure. Methods, Patients with third or fourth degree haemorrhoids were eligible for the procedure. Patients were considered suitable candidates for day case surgery based on conventional parameters. Symptoms were assessed using a previously validated symptom severity rating score. Stapled haemorrhoidopexy was carried out using a circular stapling device. Pain scores were obtained prior to discharge. Patients were admitted if pain was uncontrolled despite oral analgesia. Symptoms were re-scored at six-week follow-up. Results, Over a 70-month period 168 consecutive stapled haemorrhoidopexies were performed or directly supervised by one consultant colorectal surgeon. One hundred and ten (65%) patients were considered appropriate candidates for day case surgery by conventional criteria. Ninety-six (87.3%) patients successfully underwent stapled haemorrhoidopexy on a day case basis. Fourteen (12.7%) patients required admission on the day of surgery (5 for early postoperative bleeding, 4 for pain necessitating continuing opiate analgesia, two for urinary retention and three for surgery performed late in the day). Six (5%) patients were re-admitted postoperatively; four for pain relief and two because of urinary retention. Of the day case patients, 91 (82.7%) and 56 (50.9%) had been seen for 6 week and 6 month review, respectively, at the time of analysis. Symptom scores were 6 (pre-operatively) vs 0 (postoperatively) (P < 0.01). 76/91 (83.5%) patients reviewed at 6/52 were asymptomatic. Conclusion, Stapled haemorrhoidopexy is a safe and effective procedure that can be carried out on selected patients on a day case basis. Complications are of a similar nature to excisional haemorrhoidectomy. [source] | ||||||||||||||||||||||||||||